linux/mm/memory_hotplug.c

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/*
* linux/mm/memory_hotplug.c
*
* Copyright (C)
*/
#include <linux/stddef.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/interrupt.h>
#include <linux/pagemap.h>
#include <linux/compiler.h>
#include <linux/export.h>
#include <linux/pagevec.h>
#include <linux/writeback.h>
#include <linux/slab.h>
#include <linux/sysctl.h>
#include <linux/cpu.h>
#include <linux/memory.h>
#include <linux/memremap.h>
#include <linux/memory_hotplug.h>
#include <linux/highmem.h>
#include <linux/vmalloc.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/migrate.h>
#include <linux/page-isolation.h>
#include <linux/pfn.h>
#include <linux/suspend.h>
#include <linux/mm_inline.h>
#include <linux/firmware-map.h>
#include <linux/stop_machine.h>
mm: memory-hotplug: enable memory hotplug to handle hugepage Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:22:09 +00:00
#include <linux/hugetlb.h>
mem-hotplug: introduce movable_node boot option The hot-Pluggable field in SRAT specifies which memory is hotpluggable. As we mentioned before, if hotpluggable memory is used by the kernel, it cannot be hot-removed. So memory hotplug users may want to set all hotpluggable memory in ZONE_MOVABLE so that the kernel won't use it. Memory hotplug users may also set a node as movable node, which has ZONE_MOVABLE only, so that the whole node can be hot-removed. But the kernel cannot use memory in ZONE_MOVABLE. By doing this, the kernel cannot use memory in movable nodes. This will cause NUMA performance down. And other users may be unhappy. So we need a way to allow users to enable and disable this functionality. In this patch, we introduce movable_node boot option to allow users to choose to not to consume hotpluggable memory at early boot time and later we can set it as ZONE_MOVABLE. To achieve this, the movable_node boot option will control the memblock allocation direction. That said, after memblock is ready, before SRAT is parsed, we should allocate memory near the kernel image as we explained in the previous patches. So if movable_node boot option is set, the kernel does the following: 1. After memblock is ready, make memblock allocate memory bottom up. 2. After SRAT is parsed, make memblock behave as default, allocate memory top down. Users can specify "movable_node" in kernel commandline to enable this functionality. For those who don't use memory hotplug or who don't want to lose their NUMA performance, just don't specify anything. The kernel will work as before. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Suggested-by: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Suggested-by: Ingo Molnar <mingo@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-12 23:08:10 +00:00
#include <linux/memblock.h>
#include <linux/bootmem.h>
#include <asm/tlbflush.h>
#include "internal.h"
/*
* online_page_callback contains pointer to current page onlining function.
* Initially it is generic_online_page(). If it is required it could be
* changed by calling set_online_page_callback() for callback registration
* and restore_online_page_callback() for generic callback restore.
*/
static void generic_online_page(struct page *page);
static online_page_callback_t online_page_callback = generic_online_page;
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
static DEFINE_MUTEX(online_page_callback_lock);
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
/* The same as the cpu_hotplug lock, but for memory hotplug. */
static struct {
struct task_struct *active_writer;
struct mutex lock; /* Synchronizes accesses to refcount, */
/*
* Also blocks the new readers during
* an ongoing mem hotplug operation.
*/
int refcount;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lockdep_map dep_map;
#endif
} mem_hotplug = {
.active_writer = NULL,
.lock = __MUTEX_INITIALIZER(mem_hotplug.lock),
.refcount = 0,
#ifdef CONFIG_DEBUG_LOCK_ALLOC
.dep_map = {.name = "mem_hotplug.lock" },
#endif
};
/* Lockdep annotations for get/put_online_mems() and mem_hotplug_begin/end() */
#define memhp_lock_acquire_read() lock_map_acquire_read(&mem_hotplug.dep_map)
#define memhp_lock_acquire() lock_map_acquire(&mem_hotplug.dep_map)
#define memhp_lock_release() lock_map_release(&mem_hotplug.dep_map)
void get_online_mems(void)
{
might_sleep();
if (mem_hotplug.active_writer == current)
return;
memhp_lock_acquire_read();
mutex_lock(&mem_hotplug.lock);
mem_hotplug.refcount++;
mutex_unlock(&mem_hotplug.lock);
}
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
void put_online_mems(void)
{
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
if (mem_hotplug.active_writer == current)
return;
mutex_lock(&mem_hotplug.lock);
if (WARN_ON(!mem_hotplug.refcount))
mem_hotplug.refcount++; /* try to fix things up */
if (!--mem_hotplug.refcount && unlikely(mem_hotplug.active_writer))
wake_up_process(mem_hotplug.active_writer);
mutex_unlock(&mem_hotplug.lock);
memhp_lock_release();
}
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
void mem_hotplug_begin(void)
{
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
mem_hotplug.active_writer = current;
memhp_lock_acquire();
for (;;) {
mutex_lock(&mem_hotplug.lock);
if (likely(!mem_hotplug.refcount))
break;
__set_current_state(TASK_UNINTERRUPTIBLE);
mutex_unlock(&mem_hotplug.lock);
schedule();
}
}
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
void mem_hotplug_done(void)
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
{
mem_hotplug.active_writer = NULL;
mutex_unlock(&mem_hotplug.lock);
memhp_lock_release();
}
/* add this memory to iomem resource */
static struct resource *register_memory_resource(u64 start, u64 size)
{
struct resource *res;
res = kzalloc(sizeof(struct resource), GFP_KERNEL);
if (!res)
return ERR_PTR(-ENOMEM);
res->name = "System RAM";
res->start = start;
res->end = start + size - 1;
res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
if (request_resource(&iomem_resource, res) < 0) {
pr_debug("System RAM resource %pR cannot be added\n", res);
kfree(res);
return ERR_PTR(-EEXIST);
}
return res;
}
static void release_memory_resource(struct resource *res)
{
if (!res)
return;
release_resource(res);
kfree(res);
return;
}
#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
memory-hotplug: implement register_page_bootmem_info_section of sparse-vmemmap For removing memmap region of sparse-vmemmap which is allocated bootmem, memmap region of sparse-vmemmap needs to be registered by get_page_bootmem(). So the patch searches pages of virtual mapping and registers the pages by get_page_bootmem(). NOTE: register_page_bootmem_memmap() is not implemented for ia64, ppc, s390, and sparc. So introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node() when platform doesn't support it. It's implemented by adding a new Kconfig option named CONFIG_HAVE_BOOTMEM_INFO_NODE, which will be automatically selected by memory-hotplug feature fully supported archs(currently only on x86_64). Since we have 2 config options called MEMORY_HOTPLUG and MEMORY_HOTREMOVE used for memory hot-add and hot-remove separately, and codes in function register_page_bootmem_info_node() are only used for collecting infomation for hot-remove, so reside it under MEMORY_HOTREMOVE. Besides page_isolation.c selected by MEMORY_ISOLATION under MEMORY_HOTPLUG is also such case, move it too. [mhocko@suse.cz: put register_page_bootmem_memmap inside CONFIG_MEMORY_HOTPLUG_SPARSE] [linfeng@cn.fujitsu.com: introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node()] [mhocko@suse.cz: remove the arch specific functions without any implementation] [linfeng@cn.fujitsu.com: mm/Kconfig: move auto selects from MEMORY_HOTPLUG to MEMORY_HOTREMOVE as needed] [rientjes@google.com: fix defined but not used warning] Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Wu Jianguo <wujianguo@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Lin Feng <linfeng@cn.fujitsu.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:33:00 +00:00
void get_page_bootmem(unsigned long info, struct page *page,
unsigned long type)
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
{
page->lru.next = (struct list_head *) type;
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
SetPagePrivate(page);
set_page_private(page, info);
atomic_inc(&page->_count);
}
mm: make __free_pages_bootmem() only available at boot time In order to simpilify management of totalram_pages and zone->managed_pages, make __free_pages_bootmem() only available at boot time. With this change applied, __free_pages_bootmem() will only be used by bootmem.c and nobootmem.c at boot time, so mark it as __init. Other callers of __free_pages_bootmem() have been converted to use free_reserved_page(), which handles totalram_pages and zone->managed_pages in a safer way. This patch also fix a bug in free_pagetable() for x86_64, which should increase zone->managed_pages instead of zone->present_pages when freeing reserved pages. And now we have managed_pages_count_lock to protect totalram_pages and zone->managed_pages, so remove the redundant ppb_lock lock in put_page_bootmem(). This greatly simplifies the locking rules. Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Tejun Heo <tj@kernel.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 22:03:17 +00:00
void put_page_bootmem(struct page *page)
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
{
unsigned long type;
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
type = (unsigned long) page->lru.next;
BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
if (atomic_dec_return(&page->_count) == 1) {
ClearPagePrivate(page);
set_page_private(page, 0);
INIT_LIST_HEAD(&page->lru);
mm: make __free_pages_bootmem() only available at boot time In order to simpilify management of totalram_pages and zone->managed_pages, make __free_pages_bootmem() only available at boot time. With this change applied, __free_pages_bootmem() will only be used by bootmem.c and nobootmem.c at boot time, so mark it as __init. Other callers of __free_pages_bootmem() have been converted to use free_reserved_page(), which handles totalram_pages and zone->managed_pages in a safer way. This patch also fix a bug in free_pagetable() for x86_64, which should increase zone->managed_pages instead of zone->present_pages when freeing reserved pages. And now we have managed_pages_count_lock to protect totalram_pages and zone->managed_pages, so remove the redundant ppb_lock lock in put_page_bootmem(). This greatly simplifies the locking rules. Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Tejun Heo <tj@kernel.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 22:03:17 +00:00
free_reserved_page(page);
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
}
}
memory-hotplug: implement register_page_bootmem_info_section of sparse-vmemmap For removing memmap region of sparse-vmemmap which is allocated bootmem, memmap region of sparse-vmemmap needs to be registered by get_page_bootmem(). So the patch searches pages of virtual mapping and registers the pages by get_page_bootmem(). NOTE: register_page_bootmem_memmap() is not implemented for ia64, ppc, s390, and sparc. So introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node() when platform doesn't support it. It's implemented by adding a new Kconfig option named CONFIG_HAVE_BOOTMEM_INFO_NODE, which will be automatically selected by memory-hotplug feature fully supported archs(currently only on x86_64). Since we have 2 config options called MEMORY_HOTPLUG and MEMORY_HOTREMOVE used for memory hot-add and hot-remove separately, and codes in function register_page_bootmem_info_node() are only used for collecting infomation for hot-remove, so reside it under MEMORY_HOTREMOVE. Besides page_isolation.c selected by MEMORY_ISOLATION under MEMORY_HOTPLUG is also such case, move it too. [mhocko@suse.cz: put register_page_bootmem_memmap inside CONFIG_MEMORY_HOTPLUG_SPARSE] [linfeng@cn.fujitsu.com: introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node()] [mhocko@suse.cz: remove the arch specific functions without any implementation] [linfeng@cn.fujitsu.com: mm/Kconfig: move auto selects from MEMORY_HOTPLUG to MEMORY_HOTREMOVE as needed] [rientjes@google.com: fix defined but not used warning] Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Wu Jianguo <wujianguo@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Lin Feng <linfeng@cn.fujitsu.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:33:00 +00:00
#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
#ifndef CONFIG_SPARSEMEM_VMEMMAP
static void register_page_bootmem_info_section(unsigned long start_pfn)
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
{
unsigned long *usemap, mapsize, section_nr, i;
struct mem_section *ms;
struct page *page, *memmap;
section_nr = pfn_to_section_nr(start_pfn);
ms = __nr_to_section(section_nr);
/* Get section's memmap address */
memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
/*
* Get page for the memmap's phys address
* XXX: need more consideration for sparse_vmemmap...
*/
page = virt_to_page(memmap);
mapsize = sizeof(struct page) * PAGES_PER_SECTION;
mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
/* remember memmap's page */
for (i = 0; i < mapsize; i++, page++)
get_page_bootmem(section_nr, page, SECTION_INFO);
usemap = __nr_to_section(section_nr)->pageblock_flags;
page = virt_to_page(usemap);
mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
for (i = 0; i < mapsize; i++, page++)
get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
}
memory-hotplug: implement register_page_bootmem_info_section of sparse-vmemmap For removing memmap region of sparse-vmemmap which is allocated bootmem, memmap region of sparse-vmemmap needs to be registered by get_page_bootmem(). So the patch searches pages of virtual mapping and registers the pages by get_page_bootmem(). NOTE: register_page_bootmem_memmap() is not implemented for ia64, ppc, s390, and sparc. So introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node() when platform doesn't support it. It's implemented by adding a new Kconfig option named CONFIG_HAVE_BOOTMEM_INFO_NODE, which will be automatically selected by memory-hotplug feature fully supported archs(currently only on x86_64). Since we have 2 config options called MEMORY_HOTPLUG and MEMORY_HOTREMOVE used for memory hot-add and hot-remove separately, and codes in function register_page_bootmem_info_node() are only used for collecting infomation for hot-remove, so reside it under MEMORY_HOTREMOVE. Besides page_isolation.c selected by MEMORY_ISOLATION under MEMORY_HOTPLUG is also such case, move it too. [mhocko@suse.cz: put register_page_bootmem_memmap inside CONFIG_MEMORY_HOTPLUG_SPARSE] [linfeng@cn.fujitsu.com: introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node()] [mhocko@suse.cz: remove the arch specific functions without any implementation] [linfeng@cn.fujitsu.com: mm/Kconfig: move auto selects from MEMORY_HOTPLUG to MEMORY_HOTREMOVE as needed] [rientjes@google.com: fix defined but not used warning] Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Wu Jianguo <wujianguo@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Lin Feng <linfeng@cn.fujitsu.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:33:00 +00:00
#else /* CONFIG_SPARSEMEM_VMEMMAP */
static void register_page_bootmem_info_section(unsigned long start_pfn)
{
unsigned long *usemap, mapsize, section_nr, i;
struct mem_section *ms;
struct page *page, *memmap;
if (!pfn_valid(start_pfn))
return;
section_nr = pfn_to_section_nr(start_pfn);
ms = __nr_to_section(section_nr);
memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
usemap = __nr_to_section(section_nr)->pageblock_flags;
page = virt_to_page(usemap);
mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
for (i = 0; i < mapsize; i++, page++)
get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
}
#endif /* !CONFIG_SPARSEMEM_VMEMMAP */
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
void register_page_bootmem_info_node(struct pglist_data *pgdat)
{
unsigned long i, pfn, end_pfn, nr_pages;
int node = pgdat->node_id;
struct page *page;
struct zone *zone;
nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
page = virt_to_page(pgdat);
for (i = 0; i < nr_pages; i++, page++)
get_page_bootmem(node, page, NODE_INFO);
zone = &pgdat->node_zones[0];
for (; zone < pgdat->node_zones + MAX_NR_ZONES - 1; zone++) {
if (zone_is_initialized(zone)) {
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
nr_pages = zone->wait_table_hash_nr_entries
* sizeof(wait_queue_head_t);
nr_pages = PAGE_ALIGN(nr_pages) >> PAGE_SHIFT;
page = virt_to_page(zone->wait_table);
for (i = 0; i < nr_pages; i++, page++)
get_page_bootmem(node, page, NODE_INFO);
}
}
pfn = pgdat->node_start_pfn;
end_pfn = pgdat_end_pfn(pgdat);
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
/* register section info */
for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
/*
* Some platforms can assign the same pfn to multiple nodes - on
* node0 as well as nodeN. To avoid registering a pfn against
* multiple nodes we check that this pfn does not already
* reside in some other nodes.
*/
if (pfn_valid(pfn) && (pfn_to_nid(pfn) == node))
register_page_bootmem_info_section(pfn);
}
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
}
memory-hotplug: implement register_page_bootmem_info_section of sparse-vmemmap For removing memmap region of sparse-vmemmap which is allocated bootmem, memmap region of sparse-vmemmap needs to be registered by get_page_bootmem(). So the patch searches pages of virtual mapping and registers the pages by get_page_bootmem(). NOTE: register_page_bootmem_memmap() is not implemented for ia64, ppc, s390, and sparc. So introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node() when platform doesn't support it. It's implemented by adding a new Kconfig option named CONFIG_HAVE_BOOTMEM_INFO_NODE, which will be automatically selected by memory-hotplug feature fully supported archs(currently only on x86_64). Since we have 2 config options called MEMORY_HOTPLUG and MEMORY_HOTREMOVE used for memory hot-add and hot-remove separately, and codes in function register_page_bootmem_info_node() are only used for collecting infomation for hot-remove, so reside it under MEMORY_HOTREMOVE. Besides page_isolation.c selected by MEMORY_ISOLATION under MEMORY_HOTPLUG is also such case, move it too. [mhocko@suse.cz: put register_page_bootmem_memmap inside CONFIG_MEMORY_HOTPLUG_SPARSE] [linfeng@cn.fujitsu.com: introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node()] [mhocko@suse.cz: remove the arch specific functions without any implementation] [linfeng@cn.fujitsu.com: mm/Kconfig: move auto selects from MEMORY_HOTPLUG to MEMORY_HOTREMOVE as needed] [rientjes@google.com: fix defined but not used warning] Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Wu Jianguo <wujianguo@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Lin Feng <linfeng@cn.fujitsu.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:33:00 +00:00
#endif /* CONFIG_HAVE_BOOTMEM_INFO_NODE */
memory hotplug: register section/node id to free This patch set is to free pages which is allocated by bootmem for memory-hotremove. Some structures of memory management are allocated by bootmem. ex) memmap, etc. To remove memory physically, some of them must be freed according to circumstance. This patch set makes basis to free those pages, and free memmaps. Basic my idea is using remain members of struct page to remember information of users of bootmem (section number or node id). When the section is removing, kernel can confirm it. By this information, some issues can be solved. 1) When the memmap of removing section is allocated on other section by bootmem, it should/can be free. 2) When the memmap of removing section is allocated on the same section, it shouldn't be freed. Because the section has to be logical memory offlined already and all pages must be isolated against page allocater. If it is freed, page allocator may use it which will be removed physically soon. 3) When removing section has other section's memmap, kernel will be able to show easily which section should be removed before it for user. (Not implemented yet) 4) When the above case 2), the page isolation will be able to check and skip memmap's page when logical memory offline (offline_pages()). Current page isolation code fails in this case because this page is just reserved page and it can't distinguish this pages can be removed or not. But, it will be able to do by this patch. (Not implemented yet.) 5) The node information like pgdat has similar issues. But, this will be able to be solved too by this. (Not implemented yet, but, remembering node id in the pages.) Fortunately, current bootmem allocator just keeps PageReserved flags, and doesn't use any other members of page struct. The users of bootmem doesn't use them too. This patch: This is to register information which is node or section's id. Kernel can distinguish which node/section uses the pages allcated by bootmem. This is basis for hot-remove sections or nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:31 +00:00
static void __meminit grow_zone_span(struct zone *zone, unsigned long start_pfn,
unsigned long end_pfn)
memory_hotplug: always initialize pageblock bitmap Trying to online a new memory section that was added via memory hotplug sometimes results in crashes when the new pages are added via __free_page. Reason for that is that the pageblock bitmap isn't initialized and hence contains random stuff. That means that get_pageblock_migratetype() returns also random stuff and therefore list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); in __free_one_page() tries to do a list_add to something that isn't even necessarily a list. This happens since 86051ca5eaf5e560113ec7673462804c54284456 ("mm: fix usemap initialization") which makes sure that the pageblock bitmap gets only initialized for pages present in a zone. Unfortunately for hot-added memory the zones "grow" after the memmap and the pageblock memmap have been initialized. Which means that the new pages have an unitialized bitmap. To solve this the calls to grow_zone_span() and grow_pgdat_span() are moved to __add_zone() just before the initialization happens. The patch also moves the two functions since __add_zone() is the only caller and I didn't want to add a forward declaration. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Andy Whitcroft <apw@shadowen.org> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-14 23:05:52 +00:00
{
unsigned long old_zone_end_pfn;
zone_span_writelock(zone);
old_zone_end_pfn = zone_end_pfn(zone);
if (zone_is_empty(zone) || start_pfn < zone->zone_start_pfn)
memory_hotplug: always initialize pageblock bitmap Trying to online a new memory section that was added via memory hotplug sometimes results in crashes when the new pages are added via __free_page. Reason for that is that the pageblock bitmap isn't initialized and hence contains random stuff. That means that get_pageblock_migratetype() returns also random stuff and therefore list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); in __free_one_page() tries to do a list_add to something that isn't even necessarily a list. This happens since 86051ca5eaf5e560113ec7673462804c54284456 ("mm: fix usemap initialization") which makes sure that the pageblock bitmap gets only initialized for pages present in a zone. Unfortunately for hot-added memory the zones "grow" after the memmap and the pageblock memmap have been initialized. Which means that the new pages have an unitialized bitmap. To solve this the calls to grow_zone_span() and grow_pgdat_span() are moved to __add_zone() just before the initialization happens. The patch also moves the two functions since __add_zone() is the only caller and I didn't want to add a forward declaration. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Andy Whitcroft <apw@shadowen.org> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-14 23:05:52 +00:00
zone->zone_start_pfn = start_pfn;
zone->spanned_pages = max(old_zone_end_pfn, end_pfn) -
zone->zone_start_pfn;
zone_span_writeunlock(zone);
}
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
static void resize_zone(struct zone *zone, unsigned long start_pfn,
unsigned long end_pfn)
{
zone_span_writelock(zone);
if (end_pfn - start_pfn) {
zone->zone_start_pfn = start_pfn;
zone->spanned_pages = end_pfn - start_pfn;
} else {
/*
* make it consist as free_area_init_core(),
* if spanned_pages = 0, then keep start_pfn = 0
*/
zone->zone_start_pfn = 0;
zone->spanned_pages = 0;
}
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
zone_span_writeunlock(zone);
}
static void fix_zone_id(struct zone *zone, unsigned long start_pfn,
unsigned long end_pfn)
{
enum zone_type zid = zone_idx(zone);
int nid = zone->zone_pgdat->node_id;
unsigned long pfn;
for (pfn = start_pfn; pfn < end_pfn; pfn++)
set_page_links(pfn_to_page(pfn), zid, nid, pfn);
}
/* Can fail with -ENOMEM from allocating a wait table with vmalloc() or
* alloc_bootmem_node_nopanic()/memblock_virt_alloc_node_nopanic() */
static int __ref ensure_zone_is_initialized(struct zone *zone,
unsigned long start_pfn, unsigned long num_pages)
{
if (!zone_is_initialized(zone))
return init_currently_empty_zone(zone, start_pfn, num_pages);
return 0;
}
static int __meminit move_pfn_range_left(struct zone *z1, struct zone *z2,
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
unsigned long start_pfn, unsigned long end_pfn)
{
int ret;
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
unsigned long flags;
unsigned long z1_start_pfn;
ret = ensure_zone_is_initialized(z1, start_pfn, end_pfn - start_pfn);
if (ret)
return ret;
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
pgdat_resize_lock(z1->zone_pgdat, &flags);
/* can't move pfns which are higher than @z2 */
if (end_pfn > zone_end_pfn(z2))
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
goto out_fail;
/* the move out part must be at the left most of @z2 */
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
if (start_pfn > z2->zone_start_pfn)
goto out_fail;
/* must included/overlap */
if (end_pfn <= z2->zone_start_pfn)
goto out_fail;
/* use start_pfn for z1's start_pfn if z1 is empty */
if (!zone_is_empty(z1))
z1_start_pfn = z1->zone_start_pfn;
else
z1_start_pfn = start_pfn;
resize_zone(z1, z1_start_pfn, end_pfn);
resize_zone(z2, end_pfn, zone_end_pfn(z2));
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
pgdat_resize_unlock(z1->zone_pgdat, &flags);
fix_zone_id(z1, start_pfn, end_pfn);
return 0;
out_fail:
pgdat_resize_unlock(z1->zone_pgdat, &flags);
return -1;
}
static int __meminit move_pfn_range_right(struct zone *z1, struct zone *z2,
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
unsigned long start_pfn, unsigned long end_pfn)
{
int ret;
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
unsigned long flags;
unsigned long z2_end_pfn;
ret = ensure_zone_is_initialized(z2, start_pfn, end_pfn - start_pfn);
if (ret)
return ret;
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
pgdat_resize_lock(z1->zone_pgdat, &flags);
/* can't move pfns which are lower than @z1 */
if (z1->zone_start_pfn > start_pfn)
goto out_fail;
/* the move out part mast at the right most of @z1 */
if (zone_end_pfn(z1) > end_pfn)
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
goto out_fail;
/* must included/overlap */
if (start_pfn >= zone_end_pfn(z1))
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
goto out_fail;
/* use end_pfn for z2's end_pfn if z2 is empty */
if (!zone_is_empty(z2))
z2_end_pfn = zone_end_pfn(z2);
else
z2_end_pfn = end_pfn;
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
resize_zone(z1, z1->zone_start_pfn, start_pfn);
resize_zone(z2, start_pfn, z2_end_pfn);
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
pgdat_resize_unlock(z1->zone_pgdat, &flags);
fix_zone_id(z2, start_pfn, end_pfn);
return 0;
out_fail:
pgdat_resize_unlock(z1->zone_pgdat, &flags);
return -1;
}
static void __meminit grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn,
unsigned long end_pfn)
memory_hotplug: always initialize pageblock bitmap Trying to online a new memory section that was added via memory hotplug sometimes results in crashes when the new pages are added via __free_page. Reason for that is that the pageblock bitmap isn't initialized and hence contains random stuff. That means that get_pageblock_migratetype() returns also random stuff and therefore list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); in __free_one_page() tries to do a list_add to something that isn't even necessarily a list. This happens since 86051ca5eaf5e560113ec7673462804c54284456 ("mm: fix usemap initialization") which makes sure that the pageblock bitmap gets only initialized for pages present in a zone. Unfortunately for hot-added memory the zones "grow" after the memmap and the pageblock memmap have been initialized. Which means that the new pages have an unitialized bitmap. To solve this the calls to grow_zone_span() and grow_pgdat_span() are moved to __add_zone() just before the initialization happens. The patch also moves the two functions since __add_zone() is the only caller and I didn't want to add a forward declaration. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Andy Whitcroft <apw@shadowen.org> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-14 23:05:52 +00:00
{
unsigned long old_pgdat_end_pfn = pgdat_end_pfn(pgdat);
memory_hotplug: always initialize pageblock bitmap Trying to online a new memory section that was added via memory hotplug sometimes results in crashes when the new pages are added via __free_page. Reason for that is that the pageblock bitmap isn't initialized and hence contains random stuff. That means that get_pageblock_migratetype() returns also random stuff and therefore list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); in __free_one_page() tries to do a list_add to something that isn't even necessarily a list. This happens since 86051ca5eaf5e560113ec7673462804c54284456 ("mm: fix usemap initialization") which makes sure that the pageblock bitmap gets only initialized for pages present in a zone. Unfortunately for hot-added memory the zones "grow" after the memmap and the pageblock memmap have been initialized. Which means that the new pages have an unitialized bitmap. To solve this the calls to grow_zone_span() and grow_pgdat_span() are moved to __add_zone() just before the initialization happens. The patch also moves the two functions since __add_zone() is the only caller and I didn't want to add a forward declaration. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Andy Whitcroft <apw@shadowen.org> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-14 23:05:52 +00:00
mm/memory_hotplug.c: update start_pfn in zone and pg_data when spanned_pages == 0. If we hot-remove memory only and leave the cpus alive, the corresponding node will not be removed. But the node_start_pfn and node_spanned_pages in pg_data will be reset to 0. In this case, when we hot-add the memory back next time, the node_start_pfn will always be 0 because no pfn is less than 0. After that, if we hot-remove the memory again, it will cause kernel panic in function find_biggest_section_pfn() when it tries to scan all the pfns. The zone will also have the same problem. This patch sets start_pfn to the start_pfn of the section being added when spanned_pages of the zone or pg_data is 0. ---How to reproduce--- 1. hot-add a container with some memory and cpus; 2. hot-remove the container's memory, and leave cpus there; 3. hot-add these memory again; 4. hot-remove them again; then, the kernel will panic. ---Call trace--- BUG: unable to handle kernel paging request at 00000fff82a8cc38 IP: [<ffffffff811c0d55>] find_biggest_section_pfn+0xe5/0x180 ...... Call Trace: [<ffffffff811c1124>] __remove_zone+0x184/0x1b0 [<ffffffff811c11dc>] __remove_section+0x8c/0xb0 [<ffffffff811c12e7>] __remove_pages+0xe7/0x120 [<ffffffff81654f7c>] arch_remove_memory+0x2c/0x80 [<ffffffff81655bb6>] remove_memory+0x56/0x90 [<ffffffff813da0c8>] acpi_memory_device_remove_memory+0x48/0x73 [<ffffffff813da55a>] acpi_memory_device_notify+0x153/0x274 [<ffffffff813b6786>] acpi_ev_notify_dispatch+0x41/0x5f [<ffffffff813a3867>] acpi_os_execute_deferred+0x27/0x34 [<ffffffff81090589>] process_one_work+0x219/0x680 [<ffffffff810923be>] worker_thread+0x12e/0x320 [<ffffffff81098396>] kthread+0xc6/0xd0 [<ffffffff8167c7c4>] kernel_thread_helper+0x4/0x10 ...... ---[ end trace 96d845dbf33fee11 ]--- Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:07 +00:00
if (!pgdat->node_spanned_pages || start_pfn < pgdat->node_start_pfn)
memory_hotplug: always initialize pageblock bitmap Trying to online a new memory section that was added via memory hotplug sometimes results in crashes when the new pages are added via __free_page. Reason for that is that the pageblock bitmap isn't initialized and hence contains random stuff. That means that get_pageblock_migratetype() returns also random stuff and therefore list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); in __free_one_page() tries to do a list_add to something that isn't even necessarily a list. This happens since 86051ca5eaf5e560113ec7673462804c54284456 ("mm: fix usemap initialization") which makes sure that the pageblock bitmap gets only initialized for pages present in a zone. Unfortunately for hot-added memory the zones "grow" after the memmap and the pageblock memmap have been initialized. Which means that the new pages have an unitialized bitmap. To solve this the calls to grow_zone_span() and grow_pgdat_span() are moved to __add_zone() just before the initialization happens. The patch also moves the two functions since __add_zone() is the only caller and I didn't want to add a forward declaration. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Andy Whitcroft <apw@shadowen.org> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-14 23:05:52 +00:00
pgdat->node_start_pfn = start_pfn;
pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) -
pgdat->node_start_pfn;
}
static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn)
{
struct pglist_data *pgdat = zone->zone_pgdat;
int nr_pages = PAGES_PER_SECTION;
int nid = pgdat->node_id;
int zone_type;
unsigned long flags, pfn;
int ret;
zone_type = zone - pgdat->node_zones;
ret = ensure_zone_is_initialized(zone, phys_start_pfn, nr_pages);
if (ret)
return ret;
memory_hotplug: always initialize pageblock bitmap Trying to online a new memory section that was added via memory hotplug sometimes results in crashes when the new pages are added via __free_page. Reason for that is that the pageblock bitmap isn't initialized and hence contains random stuff. That means that get_pageblock_migratetype() returns also random stuff and therefore list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); in __free_one_page() tries to do a list_add to something that isn't even necessarily a list. This happens since 86051ca5eaf5e560113ec7673462804c54284456 ("mm: fix usemap initialization") which makes sure that the pageblock bitmap gets only initialized for pages present in a zone. Unfortunately for hot-added memory the zones "grow" after the memmap and the pageblock memmap have been initialized. Which means that the new pages have an unitialized bitmap. To solve this the calls to grow_zone_span() and grow_pgdat_span() are moved to __add_zone() just before the initialization happens. The patch also moves the two functions since __add_zone() is the only caller and I didn't want to add a forward declaration. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Andy Whitcroft <apw@shadowen.org> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-14 23:05:52 +00:00
pgdat_resize_lock(zone->zone_pgdat, &flags);
grow_zone_span(zone, phys_start_pfn, phys_start_pfn + nr_pages);
grow_pgdat_span(zone->zone_pgdat, phys_start_pfn,
phys_start_pfn + nr_pages);
pgdat_resize_unlock(zone->zone_pgdat, &flags);
memmap_init_zone(nr_pages, nid, zone_type,
phys_start_pfn, MEMMAP_HOTPLUG);
/* online_page_range is called later and expects pages reserved */
for (pfn = phys_start_pfn; pfn < phys_start_pfn + nr_pages; pfn++) {
if (!pfn_valid(pfn))
continue;
SetPageReserved(pfn_to_page(pfn));
}
return 0;
}
mm: show node to memory section relationship with symlinks in sysfs Show node to memory section relationship with symlinks in sysfs Add /sys/devices/system/node/nodeX/memoryY symlinks for all the memory sections located on nodeX. For example: /sys/devices/system/node/node1/memory135 -> ../../memory/memory135 indicates that memory section 135 resides on node1. Also revises documentation to cover this change as well as updating Documentation/ABI/testing/sysfs-devices-memory to include descriptions of memory hotremove files 'phys_device', 'phys_index', and 'state' that were previously not described there. In addition to it always being a good policy to provide users with the maximum possible amount of physical location information for resources that can be hot-added and/or hot-removed, the following are some (but likely not all) of the user benefits provided by this change. Immediate: - Provides information needed to determine the specific node on which a defective DIMM is located. This will reduce system downtime when the node or defective DIMM is swapped out. - Prevents unintended onlining of a memory section that was previously offlined due to a defective DIMM. This could happen during node hot-add when the user or node hot-add assist script onlines _all_ offlined sections due to user or script inability to identify the specific memory sections located on the hot-added node. The consequences of reintroducing the defective memory could be ugly. - Provides information needed to vary the amount and distribution of memory on specific nodes for testing or debugging purposes. Future: - Will provide information needed to identify the memory sections that need to be offlined prior to physical removal of a specific node. Symlink creation during boot was tested on 2-node x86_64, 2-node ppc64, and 2-node ia64 systems. Symlink creation during physical memory hot-add tested on a 2-node x86_64 system. Signed-off-by: Gary Hade <garyhade@us.ibm.com> Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 22:39:14 +00:00
static int __meminit __add_section(int nid, struct zone *zone,
unsigned long phys_start_pfn)
{
int ret;
if (pfn_valid(phys_start_pfn))
return -EEXIST;
ret = sparse_add_one_section(zone, phys_start_pfn);
if (ret < 0)
return ret;
ret = __add_zone(zone, phys_start_pfn);
if (ret < 0)
return ret;
mm: show node to memory section relationship with symlinks in sysfs Show node to memory section relationship with symlinks in sysfs Add /sys/devices/system/node/nodeX/memoryY symlinks for all the memory sections located on nodeX. For example: /sys/devices/system/node/node1/memory135 -> ../../memory/memory135 indicates that memory section 135 resides on node1. Also revises documentation to cover this change as well as updating Documentation/ABI/testing/sysfs-devices-memory to include descriptions of memory hotremove files 'phys_device', 'phys_index', and 'state' that were previously not described there. In addition to it always being a good policy to provide users with the maximum possible amount of physical location information for resources that can be hot-added and/or hot-removed, the following are some (but likely not all) of the user benefits provided by this change. Immediate: - Provides information needed to determine the specific node on which a defective DIMM is located. This will reduce system downtime when the node or defective DIMM is swapped out. - Prevents unintended onlining of a memory section that was previously offlined due to a defective DIMM. This could happen during node hot-add when the user or node hot-add assist script onlines _all_ offlined sections due to user or script inability to identify the specific memory sections located on the hot-added node. The consequences of reintroducing the defective memory could be ugly. - Provides information needed to vary the amount and distribution of memory on specific nodes for testing or debugging purposes. Future: - Will provide information needed to identify the memory sections that need to be offlined prior to physical removal of a specific node. Symlink creation during boot was tested on 2-node x86_64, 2-node ppc64, and 2-node ia64 systems. Symlink creation during physical memory hot-add tested on a 2-node x86_64 system. Signed-off-by: Gary Hade <garyhade@us.ibm.com> Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 22:39:14 +00:00
return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
}
/*
* Reasonably generic function for adding memory. It is
* expected that archs that support memory hotplug will
* call this function after deciding the zone to which to
* add the new pages.
*/
int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn,
unsigned long nr_pages)
{
unsigned long i;
int err = 0;
int start_sec, end_sec;
struct vmem_altmap *altmap;
/* during initialize mem_map, align hot-added range to section */
start_sec = pfn_to_section_nr(phys_start_pfn);
end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
altmap = to_vmem_altmap((unsigned long) pfn_to_page(phys_start_pfn));
if (altmap) {
/*
* Validate altmap is within bounds of the total request
*/
if (altmap->base_pfn != phys_start_pfn
|| vmem_altmap_offset(altmap) > nr_pages) {
pr_warn_once("memory add fail, invalid altmap\n");
return -EINVAL;
}
altmap->alloc = 0;
}
for (i = start_sec; i <= end_sec; i++) {
err = __add_section(nid, zone, section_nr_to_pfn(i));
/*
* EEXIST is finally dealt with by ioresource collision
* check. see add_memory() => register_memory_resource()
* Warning will be printed if there is collision.
*/
if (err && (err != -EEXIST))
break;
err = 0;
}
mm/memory hotplug: print the last vmemmap region at the end of hot add memory When hot add two nodes continuously, we found the vmemmap region info is a bit messed. The last region of node 2 is printed when node 3 hot added, like the following: Initmem setup node 2 [mem 0x0000000000000000-0xffffffffffffffff] On node 2 totalpages: 0 Built 2 zonelists in Node order, mobility grouping on. Total pages: 16090539 Policy zone: Normal init_memory_mapping: [mem 0x40000000000-0x407ffffffff] [mem 0x40000000000-0x407ffffffff] page 1G [ffffea1000000000-ffffea10001fffff] PMD -> [ffff8a077d800000-ffff8a077d9fffff] on node 2 [ffffea1000200000-ffffea10003fffff] PMD -> [ffff8a077de00000-ffff8a077dffffff] on node 2 ... [ffffea101f600000-ffffea101f9fffff] PMD -> [ffff8a074ac00000-ffff8a074affffff] on node 2 [ffffea101fa00000-ffffea101fdfffff] PMD -> [ffff8a074a800000-ffff8a074abfffff] on node 2 Initmem setup node 3 [mem 0x0000000000000000-0xffffffffffffffff] On node 3 totalpages: 0 Built 3 zonelists in Node order, mobility grouping on. Total pages: 16090539 Policy zone: Normal init_memory_mapping: [mem 0x60000000000-0x607ffffffff] [mem 0x60000000000-0x607ffffffff] page 1G [ffffea101fe00000-ffffea101fffffff] PMD -> [ffff8a074a400000-ffff8a074a5fffff] on node 2 <=== node 2 ??? [ffffea1800000000-ffffea18001fffff] PMD -> [ffff8a074a600000-ffff8a074a7fffff] on node 3 [ffffea1800200000-ffffea18005fffff] PMD -> [ffff8a074a000000-ffff8a074a3fffff] on node 3 [ffffea1800600000-ffffea18009fffff] PMD -> [ffff8a0749c00000-ffff8a0749ffffff] on node 3 ... The cause is the last region was missed at the and of hot add memory, and p_start, p_end, node_start were not reset, so when hot add memory to a new node, it will consider they are not contiguous blocks and print the previous one. So we print the last vmemmap region at the end of hot add memory to avoid the confusion. Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-24 23:58:42 +00:00
vmemmap_populate_print_last();
return err;
}
EXPORT_SYMBOL_GPL(__add_pages);
#ifdef CONFIG_MEMORY_HOTREMOVE
/* find the smallest valid pfn in the range [start_pfn, end_pfn) */
static int find_smallest_section_pfn(int nid, struct zone *zone,
unsigned long start_pfn,
unsigned long end_pfn)
{
struct mem_section *ms;
for (; start_pfn < end_pfn; start_pfn += PAGES_PER_SECTION) {
ms = __pfn_to_section(start_pfn);
if (unlikely(!valid_section(ms)))
continue;
if (unlikely(pfn_to_nid(start_pfn) != nid))
continue;
if (zone && zone != page_zone(pfn_to_page(start_pfn)))
continue;
return start_pfn;
}
return 0;
}
/* find the biggest valid pfn in the range [start_pfn, end_pfn). */
static int find_biggest_section_pfn(int nid, struct zone *zone,
unsigned long start_pfn,
unsigned long end_pfn)
{
struct mem_section *ms;
unsigned long pfn;
/* pfn is the end pfn of a memory section. */
pfn = end_pfn - 1;
for (; pfn >= start_pfn; pfn -= PAGES_PER_SECTION) {
ms = __pfn_to_section(pfn);
if (unlikely(!valid_section(ms)))
continue;
if (unlikely(pfn_to_nid(pfn) != nid))
continue;
if (zone && zone != page_zone(pfn_to_page(pfn)))
continue;
return pfn;
}
return 0;
}
static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
unsigned long end_pfn)
{
unsigned long zone_start_pfn = zone->zone_start_pfn;
unsigned long z = zone_end_pfn(zone); /* zone_end_pfn namespace clash */
unsigned long zone_end_pfn = z;
unsigned long pfn;
struct mem_section *ms;
int nid = zone_to_nid(zone);
zone_span_writelock(zone);
if (zone_start_pfn == start_pfn) {
/*
* If the section is smallest section in the zone, it need
* shrink zone->zone_start_pfn and zone->zone_spanned_pages.
* In this case, we find second smallest valid mem_section
* for shrinking zone.
*/
pfn = find_smallest_section_pfn(nid, zone, end_pfn,
zone_end_pfn);
if (pfn) {
zone->zone_start_pfn = pfn;
zone->spanned_pages = zone_end_pfn - pfn;
}
} else if (zone_end_pfn == end_pfn) {
/*
* If the section is biggest section in the zone, it need
* shrink zone->spanned_pages.
* In this case, we find second biggest valid mem_section for
* shrinking zone.
*/
pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn,
start_pfn);
if (pfn)
zone->spanned_pages = pfn - zone_start_pfn + 1;
}
/*
* The section is not biggest or smallest mem_section in the zone, it
* only creates a hole in the zone. So in this case, we need not
* change the zone. But perhaps, the zone has only hole data. Thus
* it check the zone has only hole or not.
*/
pfn = zone_start_pfn;
for (; pfn < zone_end_pfn; pfn += PAGES_PER_SECTION) {
ms = __pfn_to_section(pfn);
if (unlikely(!valid_section(ms)))
continue;
if (page_zone(pfn_to_page(pfn)) != zone)
continue;
/* If the section is current section, it continues the loop */
if (start_pfn == pfn)
continue;
/* If we find valid section, we have nothing to do */
zone_span_writeunlock(zone);
return;
}
/* The zone has no valid section */
zone->zone_start_pfn = 0;
zone->spanned_pages = 0;
zone_span_writeunlock(zone);
}
static void shrink_pgdat_span(struct pglist_data *pgdat,
unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long pgdat_start_pfn = pgdat->node_start_pfn;
unsigned long p = pgdat_end_pfn(pgdat); /* pgdat_end_pfn namespace clash */
unsigned long pgdat_end_pfn = p;
unsigned long pfn;
struct mem_section *ms;
int nid = pgdat->node_id;
if (pgdat_start_pfn == start_pfn) {
/*
* If the section is smallest section in the pgdat, it need
* shrink pgdat->node_start_pfn and pgdat->node_spanned_pages.
* In this case, we find second smallest valid mem_section
* for shrinking zone.
*/
pfn = find_smallest_section_pfn(nid, NULL, end_pfn,
pgdat_end_pfn);
if (pfn) {
pgdat->node_start_pfn = pfn;
pgdat->node_spanned_pages = pgdat_end_pfn - pfn;
}
} else if (pgdat_end_pfn == end_pfn) {
/*
* If the section is biggest section in the pgdat, it need
* shrink pgdat->node_spanned_pages.
* In this case, we find second biggest valid mem_section for
* shrinking zone.
*/
pfn = find_biggest_section_pfn(nid, NULL, pgdat_start_pfn,
start_pfn);
if (pfn)
pgdat->node_spanned_pages = pfn - pgdat_start_pfn + 1;
}
/*
* If the section is not biggest or smallest mem_section in the pgdat,
* it only creates a hole in the pgdat. So in this case, we need not
* change the pgdat.
* But perhaps, the pgdat has only hole data. Thus it check the pgdat
* has only hole or not.
*/
pfn = pgdat_start_pfn;
for (; pfn < pgdat_end_pfn; pfn += PAGES_PER_SECTION) {
ms = __pfn_to_section(pfn);
if (unlikely(!valid_section(ms)))
continue;
if (pfn_to_nid(pfn) != nid)
continue;
/* If the section is current section, it continues the loop */
if (start_pfn == pfn)
continue;
/* If we find valid section, we have nothing to do */
return;
}
/* The pgdat has no valid section */
pgdat->node_start_pfn = 0;
pgdat->node_spanned_pages = 0;
}
static void __remove_zone(struct zone *zone, unsigned long start_pfn)
{
struct pglist_data *pgdat = zone->zone_pgdat;
int nr_pages = PAGES_PER_SECTION;
int zone_type;
unsigned long flags;
zone_type = zone - pgdat->node_zones;
pgdat_resize_lock(zone->zone_pgdat, &flags);
shrink_zone_span(zone, start_pfn, start_pfn + nr_pages);
shrink_pgdat_span(pgdat, start_pfn, start_pfn + nr_pages);
pgdat_resize_unlock(zone->zone_pgdat, &flags);
}
static int __remove_section(struct zone *zone, struct mem_section *ms,
unsigned long map_offset)
{
unsigned long start_pfn;
int scn_nr;
int ret = -EINVAL;
if (!valid_section(ms))
return ret;
ret = unregister_memory_section(ms);
if (ret)
return ret;
scn_nr = __section_nr(ms);
start_pfn = section_nr_to_pfn(scn_nr);
__remove_zone(zone, start_pfn);
sparse_remove_one_section(zone, ms, map_offset);
return 0;
}
/**
* __remove_pages() - remove sections of pages from a zone
* @zone: zone from which pages need to be removed
* @phys_start_pfn: starting pageframe (must be aligned to start of a section)
* @nr_pages: number of pages to remove (must be multiple of section size)
*
* Generic helper function to remove section mappings and sysfs entries
* for the section of the memory we are removing. Caller needs to make
* sure that pages are marked reserved and zones are adjust properly by
* calling offline_pages().
*/
int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
unsigned long nr_pages)
{
unsigned long i;
unsigned long map_offset = 0;
int sections_to_remove, ret = 0;
/* In the ZONE_DEVICE case device driver owns the memory region */
if (is_dev_zone(zone)) {
struct page *page = pfn_to_page(phys_start_pfn);
struct vmem_altmap *altmap;
altmap = to_vmem_altmap((unsigned long) page);
if (altmap)
map_offset = vmem_altmap_offset(altmap);
} else {
resource_size_t start, size;
start = phys_start_pfn << PAGE_SHIFT;
size = nr_pages * PAGE_SIZE;
ret = release_mem_region_adjustable(&iomem_resource, start,
size);
if (ret) {
resource_size_t endres = start + size - 1;
pr_warn("Unable to release resource <%pa-%pa> (%d)\n",
&start, &endres, ret);
}
}
/*
* We can only remove entire sections
*/
BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
BUG_ON(nr_pages % PAGES_PER_SECTION);
sections_to_remove = nr_pages / PAGES_PER_SECTION;
for (i = 0; i < sections_to_remove; i++) {
unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
ret = __remove_section(zone, __pfn_to_section(pfn), map_offset);
map_offset = 0;
if (ret)
break;
}
return ret;
}
EXPORT_SYMBOL_GPL(__remove_pages);
#endif /* CONFIG_MEMORY_HOTREMOVE */
int set_online_page_callback(online_page_callback_t callback)
{
int rc = -EINVAL;
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
get_online_mems();
mutex_lock(&online_page_callback_lock);
if (online_page_callback == generic_online_page) {
online_page_callback = callback;
rc = 0;
}
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
mutex_unlock(&online_page_callback_lock);
put_online_mems();
return rc;
}
EXPORT_SYMBOL_GPL(set_online_page_callback);
int restore_online_page_callback(online_page_callback_t callback)
{
int rc = -EINVAL;
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
get_online_mems();
mutex_lock(&online_page_callback_lock);
if (online_page_callback == callback) {
online_page_callback = generic_online_page;
rc = 0;
}
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
mutex_unlock(&online_page_callback_lock);
put_online_mems();
return rc;
}
EXPORT_SYMBOL_GPL(restore_online_page_callback);
void __online_page_set_limits(struct page *page)
{
}
EXPORT_SYMBOL_GPL(__online_page_set_limits);
void __online_page_increment_counters(struct page *page)
{
mm: correctly update zone->managed_pages Enhance adjust_managed_page_count() to adjust totalhigh_pages for highmem pages. And change code which directly adjusts totalram_pages to use adjust_managed_page_count() because it adjusts totalram_pages, totalhigh_pages and zone->managed_pages altogether in a safe way. Remove inc_totalhigh_pages() and dec_totalhigh_pages() from xen/balloon driver bacause adjust_managed_page_count() has already adjusted totalhigh_pages. This patch also fixes two bugs: 1) enhances virtio_balloon driver to adjust totalhigh_pages when reserve/unreserve pages. 2) enhance memory_hotplug.c to adjust totalhigh_pages when hot-removing memory. We still need to deal with modifications of totalram_pages in file arch/powerpc/platforms/pseries/cmm.c, but need help from PPC experts. [akpm@linux-foundation.org: remove ifdef, per Wanpeng Li, virtio_balloon.c cleanup, per Sergei] [akpm@linux-foundation.org: export adjust_managed_page_count() to modules, for drivers/virtio/virtio_balloon.c] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 22:03:21 +00:00
adjust_managed_page_count(page, 1);
}
EXPORT_SYMBOL_GPL(__online_page_increment_counters);
void __online_page_free(struct page *page)
{
mm: correctly update zone->managed_pages Enhance adjust_managed_page_count() to adjust totalhigh_pages for highmem pages. And change code which directly adjusts totalram_pages to use adjust_managed_page_count() because it adjusts totalram_pages, totalhigh_pages and zone->managed_pages altogether in a safe way. Remove inc_totalhigh_pages() and dec_totalhigh_pages() from xen/balloon driver bacause adjust_managed_page_count() has already adjusted totalhigh_pages. This patch also fixes two bugs: 1) enhances virtio_balloon driver to adjust totalhigh_pages when reserve/unreserve pages. 2) enhance memory_hotplug.c to adjust totalhigh_pages when hot-removing memory. We still need to deal with modifications of totalram_pages in file arch/powerpc/platforms/pseries/cmm.c, but need help from PPC experts. [akpm@linux-foundation.org: remove ifdef, per Wanpeng Li, virtio_balloon.c cleanup, per Sergei] [akpm@linux-foundation.org: export adjust_managed_page_count() to modules, for drivers/virtio/virtio_balloon.c] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 22:03:21 +00:00
__free_reserved_page(page);
}
EXPORT_SYMBOL_GPL(__online_page_free);
static void generic_online_page(struct page *page)
{
__online_page_set_limits(page);
__online_page_increment_counters(page);
__online_page_free(page);
}
static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
void *arg)
{
unsigned long i;
unsigned long onlined_pages = *(unsigned long *)arg;
struct page *page;
if (PageReserved(pfn_to_page(start_pfn)))
for (i = 0; i < nr_pages; i++) {
page = pfn_to_page(start_pfn + i);
(*online_page_callback)(page);
onlined_pages++;
}
*(unsigned long *)arg = onlined_pages;
return 0;
}
#ifdef CONFIG_MOVABLE_NODE
/*
* When CONFIG_MOVABLE_NODE, we permit onlining of a node which doesn't have
* normal memory.
*/
static bool can_online_high_movable(struct zone *zone)
{
return true;
}
#else /* CONFIG_MOVABLE_NODE */
/* ensure every online node has NORMAL memory */
static bool can_online_high_movable(struct zone *zone)
{
return node_state(zone_to_nid(zone), N_NORMAL_MEMORY);
}
#endif /* CONFIG_MOVABLE_NODE */
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
/* check which state of node_states will be changed when online memory */
static void node_states_check_changes_online(unsigned long nr_pages,
struct zone *zone, struct memory_notify *arg)
{
int nid = zone_to_nid(zone);
enum zone_type zone_last = ZONE_NORMAL;
/*
* If we have HIGHMEM or movable node, node_states[N_NORMAL_MEMORY]
* contains nodes which have zones of 0...ZONE_NORMAL,
* set zone_last to ZONE_NORMAL.
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
*
* If we don't have HIGHMEM nor movable node,
* node_states[N_NORMAL_MEMORY] contains nodes which have zones of
* 0...ZONE_MOVABLE, set zone_last to ZONE_MOVABLE.
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
*/
if (N_MEMORY == N_NORMAL_MEMORY)
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
zone_last = ZONE_MOVABLE;
/*
* if the memory to be online is in a zone of 0...zone_last, and
* the zones of 0...zone_last don't have memory before online, we will
* need to set the node to node_states[N_NORMAL_MEMORY] after
* the memory is online.
*/
if (zone_idx(zone) <= zone_last && !node_state(nid, N_NORMAL_MEMORY))
arg->status_change_nid_normal = nid;
else
arg->status_change_nid_normal = -1;
#ifdef CONFIG_HIGHMEM
/*
* If we have movable node, node_states[N_HIGH_MEMORY]
* contains nodes which have zones of 0...ZONE_HIGHMEM,
* set zone_last to ZONE_HIGHMEM.
*
* If we don't have movable node, node_states[N_NORMAL_MEMORY]
* contains nodes which have zones of 0...ZONE_MOVABLE,
* set zone_last to ZONE_MOVABLE.
*/
zone_last = ZONE_HIGHMEM;
if (N_MEMORY == N_HIGH_MEMORY)
zone_last = ZONE_MOVABLE;
if (zone_idx(zone) <= zone_last && !node_state(nid, N_HIGH_MEMORY))
arg->status_change_nid_high = nid;
else
arg->status_change_nid_high = -1;
#else
arg->status_change_nid_high = arg->status_change_nid_normal;
#endif
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
/*
* if the node don't have memory befor online, we will need to
* set the node to node_states[N_MEMORY] after the memory
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
* is online.
*/
if (!node_state(nid, N_MEMORY))
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
arg->status_change_nid = nid;
else
arg->status_change_nid = -1;
}
static void node_states_set_node(int node, struct memory_notify *arg)
{
if (arg->status_change_nid_normal >= 0)
node_set_state(node, N_NORMAL_MEMORY);
if (arg->status_change_nid_high >= 0)
node_set_state(node, N_HIGH_MEMORY);
node_set_state(node, N_MEMORY);
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
}
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
/* Must be protected by mem_hotplug_begin() */
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type)
{
unsigned long flags;
unsigned long onlined_pages = 0;
struct zone *zone;
int need_zonelists_rebuild = 0;
int nid;
int ret;
struct memory_notify arg;
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
/*
* This doesn't need a lock to do pfn_to_page().
* The section can't be removed here because of the
* memory_block->state_mutex.
*/
zone = page_zone(pfn_to_page(pfn));
if ((zone_idx(zone) > ZONE_NORMAL ||
online_type == MMOP_ONLINE_MOVABLE) &&
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
!can_online_high_movable(zone))
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
return -EINVAL;
if (online_type == MMOP_ONLINE_KERNEL &&
zone_idx(zone) == ZONE_MOVABLE) {
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
if (move_pfn_range_left(zone - 1, zone, pfn, pfn + nr_pages))
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
return -EINVAL;
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
}
if (online_type == MMOP_ONLINE_MOVABLE &&
zone_idx(zone) == ZONE_MOVABLE - 1) {
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
if (move_pfn_range_right(zone, zone + 1, pfn, pfn + nr_pages))
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
return -EINVAL;
mm, memory-hotplug: dynamic configure movable memory and portion memory Add online_movable and online_kernel for logic memory hotplug. This is the dynamic version of "movablecore" & "kernelcore". We have the same reason to introduce it as to introduce "movablecore" & "kernelcore". It has the same motive as "movablecore" & "kernelcore", but it is dynamic/running-time: o We can configure memory as kernelcore or movablecore after boot. Userspace workload is increased, we need more hugepage, we can't use "online_movable" to add memory and allow the system use more THP(transparent-huge-page), vice-verse when kernel workload is increase. Also help for virtualization to dynamic configure host/guest's memory, to save/(reduce waste) memory. Memory capacity on Demand o When a new node is physically online after boot, we need to use "online_movable" or "online_kernel" to configure/portion it as we expected when we logic-online it. This configuration also helps for physically-memory-migrate. o all benefit as the same as existed "movablecore" & "kernelcore". o Preparing for movable-node, which is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). (Note, we don't introduce movable-node here.) Action behavior: When a memoryblock/memorysection is onlined by "online_movable", the kernel will not have directly reference to the page of the memoryblock, thus we can remove that memory any time when needed. When it is online by "online_kernel", the kernel can use it. When it is online by "online", the zone type doesn't changed. Current constraints: Only the memoryblock which is adjacent to the ZONE_MOVABLE can be online from ZONE_NORMAL to ZONE_MOVABLE. [akpm@linux-foundation.org: use min_t, cleanups] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:03:16 +00:00
}
/* Previous code may changed the zone of the pfn range */
zone = page_zone(pfn_to_page(pfn));
arg.start_pfn = pfn;
arg.nr_pages = nr_pages;
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
node_states_check_changes_online(nr_pages, zone, &arg);
nid = pfn_to_nid(pfn);
ret = memory_notify(MEM_GOING_ONLINE, &arg);
ret = notifier_to_errno(ret);
if (ret) {
memory_notify(MEM_CANCEL_ONLINE, &arg);
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
return ret;
}
/*
* If this zone is not populated, then it is not in zonelist.
* This means the page allocator ignores this zone.
* So, zonelist must be updated after online.
*/
mutex_lock(&zonelists_mutex);
if (!populated_zone(zone)) {
need_zonelists_rebuild = 1;
build_all_zonelists(NULL, zone);
}
ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
online_pages_range);
if (ret) {
if (need_zonelists_rebuild)
zone_pcp_reset(zone);
mutex_unlock(&zonelists_mutex);
printk(KERN_DEBUG "online_pages [mem %#010llx-%#010llx] failed\n",
(unsigned long long) pfn << PAGE_SHIFT,
(((unsigned long long) pfn + nr_pages)
<< PAGE_SHIFT) - 1);
memory_notify(MEM_CANCEL_ONLINE, &arg);
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
return ret;
}
zone->present_pages += onlined_pages;
pgdat_resize_lock(zone->zone_pgdat, &flags);
zone->zone_pgdat->node_present_pages += onlined_pages;
pgdat_resize_unlock(zone->zone_pgdat, &flags);
mm/hotplug: correctly add new zone to all other nodes' zone lists When online_pages() is called to add new memory to an empty zone, it rebuilds all zone lists by calling build_all_zonelists(). But there's a bug which prevents the new zone to be added to other nodes' zone lists. online_pages() { build_all_zonelists() ..... node_set_state(zone_to_nid(zone), N_HIGH_MEMORY) } Here the node of the zone is put into N_HIGH_MEMORY state after calling build_all_zonelists(), but build_all_zonelists() only adds zones from nodes in N_HIGH_MEMORY state to the fallback zone lists. build_all_zonelists() ->__build_all_zonelists() ->build_zonelists() ->find_next_best_node() ->for_each_node_state(n, N_HIGH_MEMORY) So memory in the new zone will never be used by other nodes, and it may cause strange behavor when system is under memory pressure. So put node into N_HIGH_MEMORY state before calling build_all_zonelists(). Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Signed-off-by: Jiang Liu <liuj97@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Keping Chen <chenkeping@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 23:43:30 +00:00
if (onlined_pages) {
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
node_states_set_node(zone_to_nid(zone), &arg);
mm/hotplug: correctly add new zone to all other nodes' zone lists When online_pages() is called to add new memory to an empty zone, it rebuilds all zone lists by calling build_all_zonelists(). But there's a bug which prevents the new zone to be added to other nodes' zone lists. online_pages() { build_all_zonelists() ..... node_set_state(zone_to_nid(zone), N_HIGH_MEMORY) } Here the node of the zone is put into N_HIGH_MEMORY state after calling build_all_zonelists(), but build_all_zonelists() only adds zones from nodes in N_HIGH_MEMORY state to the fallback zone lists. build_all_zonelists() ->__build_all_zonelists() ->build_zonelists() ->find_next_best_node() ->for_each_node_state(n, N_HIGH_MEMORY) So memory in the new zone will never be used by other nodes, and it may cause strange behavor when system is under memory pressure. So put node into N_HIGH_MEMORY state before calling build_all_zonelists(). Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Signed-off-by: Jiang Liu <liuj97@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Keping Chen <chenkeping@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 23:43:30 +00:00
if (need_zonelists_rebuild)
build_all_zonelists(NULL, NULL);
mm/hotplug: correctly add new zone to all other nodes' zone lists When online_pages() is called to add new memory to an empty zone, it rebuilds all zone lists by calling build_all_zonelists(). But there's a bug which prevents the new zone to be added to other nodes' zone lists. online_pages() { build_all_zonelists() ..... node_set_state(zone_to_nid(zone), N_HIGH_MEMORY) } Here the node of the zone is put into N_HIGH_MEMORY state after calling build_all_zonelists(), but build_all_zonelists() only adds zones from nodes in N_HIGH_MEMORY state to the fallback zone lists. build_all_zonelists() ->__build_all_zonelists() ->build_zonelists() ->find_next_best_node() ->for_each_node_state(n, N_HIGH_MEMORY) So memory in the new zone will never be used by other nodes, and it may cause strange behavor when system is under memory pressure. So put node into N_HIGH_MEMORY state before calling build_all_zonelists(). Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Signed-off-by: Jiang Liu <liuj97@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Keping Chen <chenkeping@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 23:43:30 +00:00
else
zone_pcp_update(zone);
}
mutex_unlock(&zonelists_mutex);
init_per_zone_wmark_min();
mm/hotplug: correctly add new zone to all other nodes' zone lists When online_pages() is called to add new memory to an empty zone, it rebuilds all zone lists by calling build_all_zonelists(). But there's a bug which prevents the new zone to be added to other nodes' zone lists. online_pages() { build_all_zonelists() ..... node_set_state(zone_to_nid(zone), N_HIGH_MEMORY) } Here the node of the zone is put into N_HIGH_MEMORY state after calling build_all_zonelists(), but build_all_zonelists() only adds zones from nodes in N_HIGH_MEMORY state to the fallback zone lists. build_all_zonelists() ->__build_all_zonelists() ->build_zonelists() ->find_next_best_node() ->for_each_node_state(n, N_HIGH_MEMORY) So memory in the new zone will never be used by other nodes, and it may cause strange behavor when system is under memory pressure. So put node into N_HIGH_MEMORY state before calling build_all_zonelists(). Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Signed-off-by: Jiang Liu <liuj97@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Keping Chen <chenkeping@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 23:43:30 +00:00
if (onlined_pages)
kswapd_run(zone_to_nid(zone));
mem-hotplug: avoid multiple zones sharing same boot strapping boot_pageset For each new populated zone of hotadded node, need to update its pagesets with dynamically allocated per_cpu_pageset struct for all possible CPUs: 1) Detach zone->pageset from the shared boot_pageset at end of __build_all_zonelists(). 2) Use mutex to protect zone->pageset when it's still shared in onlined_pages() Otherwises, multiple zones of different nodes would share same boot strapping boot_pageset for same CPU, which will finally cause below kernel panic: ------------[ cut here ]------------ kernel BUG at mm/page_alloc.c:1239! invalid opcode: 0000 [#1] SMP ... Call Trace: [<ffffffff811300c1>] __alloc_pages_nodemask+0x131/0x7b0 [<ffffffff81162e67>] alloc_pages_current+0x87/0xd0 [<ffffffff81128407>] __page_cache_alloc+0x67/0x70 [<ffffffff811325f0>] __do_page_cache_readahead+0x120/0x260 [<ffffffff81132751>] ra_submit+0x21/0x30 [<ffffffff811329c6>] ondemand_readahead+0x166/0x2c0 [<ffffffff81132ba0>] page_cache_async_readahead+0x80/0xa0 [<ffffffff8112a0e4>] generic_file_aio_read+0x364/0x670 [<ffffffff81266cfa>] nfs_file_read+0xca/0x130 [<ffffffff8117b20a>] do_sync_read+0xfa/0x140 [<ffffffff8117bf75>] vfs_read+0xb5/0x1a0 [<ffffffff8117c151>] sys_read+0x51/0x80 [<ffffffff8103c032>] system_call_fastpath+0x16/0x1b RIP [<ffffffff8112ff13>] get_page_from_freelist+0x883/0x900 RSP <ffff88000d1e78a8> ---[ end trace 4bda28328b9990db ] [akpm@linux-foundation.org: merge fix] Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Reviewed-by: Andi Kleen <andi.kleen@intel.com> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-24 21:32:51 +00:00
vm_total_pages = nr_free_pagecache_pages();
writeback_set_ratelimit();
if (onlined_pages)
memory_notify(MEM_ONLINE, &arg);
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
return 0;
}
#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
static void reset_node_present_pages(pg_data_t *pgdat)
{
struct zone *z;
for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
z->present_pages = 0;
pgdat->node_present_pages = 0;
}
/* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
{
struct pglist_data *pgdat;
unsigned long zones_size[MAX_NR_ZONES] = {0};
unsigned long zholes_size[MAX_NR_ZONES] = {0};
unsigned long start_pfn = PFN_DOWN(start);
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
pgdat = NODE_DATA(nid);
if (!pgdat) {
pgdat = arch_alloc_nodedata(nid);
if (!pgdat)
return NULL;
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
arch_refresh_nodedata(nid, pgdat);
mm/memory hotplug: postpone the reset of obsolete pgdat Qiu Xishi reported the following BUG when testing hot-add/hot-remove node under stress condition: BUG: unable to handle kernel paging request at 0000000000025f60 IP: next_online_pgdat+0x1/0x50 PGD 0 Oops: 0000 [#1] SMP ACPI: Device does not support D3cold Modules linked in: fuse nls_iso8859_1 nls_cp437 vfat fat loop dm_mod coretemp mperf crc32c_intel ghash_clmulni_intel aesni_intel ablk_helper cryptd lrw gf128mul glue_helper aes_x86_64 pcspkr microcode igb dca i2c_algo_bit ipv6 megaraid_sas iTCO_wdt i2c_i801 i2c_core iTCO_vendor_support tg3 sg hwmon ptp lpc_ich pps_core mfd_core acpi_pad rtc_cmos button ext3 jbd mbcache sd_mod crc_t10dif scsi_dh_alua scsi_dh_rdac scsi_dh_hp_sw scsi_dh_emc scsi_dh ahci libahci libata scsi_mod [last unloaded: rasf] CPU: 23 PID: 238 Comm: kworker/23:1 Tainted: G O 3.10.15-5885-euler0302 #1 Hardware name: HUAWEI TECHNOLOGIES CO.,LTD. Huawei N1/Huawei N1, BIOS V100R001 03/02/2015 Workqueue: events vmstat_update task: ffffa800d32c0000 ti: ffffa800d32ae000 task.ti: ffffa800d32ae000 RIP: 0010: next_online_pgdat+0x1/0x50 RSP: 0018:ffffa800d32afce8 EFLAGS: 00010286 RAX: 0000000000001440 RBX: ffffffff81da53b8 RCX: 0000000000000082 RDX: 0000000000000000 RSI: 0000000000000082 RDI: 0000000000000000 RBP: ffffa800d32afd28 R08: ffffffff81c93bfc R09: ffffffff81cbdc96 R10: 00000000000040ec R11: 00000000000000a0 R12: ffffa800fffb3440 R13: ffffa800d32afd38 R14: 0000000000000017 R15: ffffa800e6616800 FS: 0000000000000000(0000) GS:ffffa800e6600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000025f60 CR3: 0000000001a0b000 CR4: 00000000001407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: refresh_cpu_vm_stats+0xd0/0x140 vmstat_update+0x11/0x50 process_one_work+0x194/0x3d0 worker_thread+0x12b/0x410 kthread+0xc6/0xd0 ret_from_fork+0x7c/0xb0 The cause is the "memset(pgdat, 0, sizeof(*pgdat))" at the end of try_offline_node, which will reset all the content of pgdat to 0, as the pgdat is accessed lock-free, so that the users still using the pgdat will panic, such as the vmstat_update routine. process A: offline node XX: vmstat_updat() refresh_cpu_vm_stats() for_each_populated_zone() find online node XX cond_resched() offline cpu and memory, then try_offline_node() node_set_offline(nid), and memset(pgdat, 0, sizeof(*pgdat)) zone = next_zone(zone) pg_data_t *pgdat = zone->zone_pgdat; // here pgdat is NULL now next_online_pgdat(pgdat) next_online_node(pgdat->node_id); // NULL pointer access So the solution here is postponing the reset of obsolete pgdat from try_offline_node() to hotadd_new_pgdat(), and just resetting pgdat->nr_zones and pgdat->classzone_idx to be 0 rather than the memset 0 to avoid breaking pointer information in pgdat. Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Reported-by: Xishi Qiu <qiuxishi@huawei.com> Suggested-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Xie XiuQi <xiexiuqi@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-03-25 22:55:20 +00:00
} else {
/* Reset the nr_zones and classzone_idx to 0 before reuse */
pgdat->nr_zones = 0;
pgdat->classzone_idx = 0;
}
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
/* we can use NODE_DATA(nid) from here */
/* init node's zones as empty zones, we don't have any present pages.*/
free_area_init_node(nid, zones_size, start_pfn, zholes_size);
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
/*
* The node we allocated has no zone fallback lists. For avoiding
* to access not-initialized zonelist, build here.
*/
mutex_lock(&zonelists_mutex);
mm/hotplug: correctly setup fallback zonelists when creating new pgdat When hotadd_new_pgdat() is called to create new pgdat for a new node, a fallback zonelist should be created for the new node. There's code to try to achieve that in hotadd_new_pgdat() as below: /* * The node we allocated has no zone fallback lists. For avoiding * to access not-initialized zonelist, build here. */ mutex_lock(&zonelists_mutex); build_all_zonelists(pgdat, NULL); mutex_unlock(&zonelists_mutex); But it doesn't work as expected. When hotadd_new_pgdat() is called, the new node is still in offline state because node_set_online(nid) hasn't been called yet. And build_all_zonelists() only builds zonelists for online nodes as: for_each_online_node(nid) { pg_data_t *pgdat = NODE_DATA(nid); build_zonelists(pgdat); build_zonelist_cache(pgdat); } Though we hope to create zonelist for the new pgdat, but it doesn't. So add a new parameter "pgdat" the build_all_zonelists() to build pgdat for the new pgdat too. Signed-off-by: Jiang Liu <liuj97@gmail.com> Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Keping Chen <chenkeping@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 23:43:28 +00:00
build_all_zonelists(pgdat, NULL);
mutex_unlock(&zonelists_mutex);
/*
* zone->managed_pages is set to an approximate value in
* free_area_init_core(), which will cause
* /sys/device/system/node/nodeX/meminfo has wrong data.
* So reset it to 0 before any memory is onlined.
*/
reset_node_managed_pages(pgdat);
/*
* When memory is hot-added, all the memory is in offline state. So
* clear all zones' present_pages because they will be updated in
* online_pages() and offline_pages().
*/
reset_node_present_pages(pgdat);
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
return pgdat;
}
static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
{
arch_refresh_nodedata(nid, NULL);
arch_free_nodedata(pgdat);
return;
}
/**
* try_online_node - online a node if offlined
*
* called by cpu_up() to online a node without onlined memory.
*/
int try_online_node(int nid)
{
pg_data_t *pgdat;
int ret;
if (node_online(nid))
return 0;
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
mem_hotplug_begin();
pgdat = hotadd_new_pgdat(nid, 0);
if (!pgdat) {
pr_err("Cannot online node %d due to NULL pgdat\n", nid);
ret = -ENOMEM;
goto out;
}
node_set_online(nid);
ret = register_one_node(nid);
BUG_ON(ret);
if (pgdat->node_zonelists->_zonerefs->zone == NULL) {
mutex_lock(&zonelists_mutex);
build_all_zonelists(NULL, NULL);
mutex_unlock(&zonelists_mutex);
}
out:
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
mem_hotplug_done();
return ret;
}
static int check_hotplug_memory_range(u64 start, u64 size)
{
u64 start_pfn = PFN_DOWN(start);
u64 nr_pages = size >> PAGE_SHIFT;
/* Memory range must be aligned with section */
if ((start_pfn & ~PAGE_SECTION_MASK) ||
(nr_pages % PAGES_PER_SECTION) || (!nr_pages)) {
pr_err("Section-unaligned hotplug range: start 0x%llx, size 0x%llx\n",
(unsigned long long)start,
(unsigned long long)size);
return -EINVAL;
}
return 0;
}
memory-hotplug: add zone_for_memory() for selecting zone for new memory This series of patches fixes a problem when adding memory in bad manner. For example: for a x86_64 machine booted with "mem=400M" and with 2GiB memory installed, following commands cause problem: # echo 0x40000000 > /sys/devices/system/memory/probe [ 28.613895] init_memory_mapping: [mem 0x40000000-0x47ffffff] # echo 0x48000000 > /sys/devices/system/memory/probe [ 28.693675] init_memory_mapping: [mem 0x48000000-0x4fffffff] # echo online_movable > /sys/devices/system/memory/memory9/state # echo 0x50000000 > /sys/devices/system/memory/probe [ 29.084090] init_memory_mapping: [mem 0x50000000-0x57ffffff] # echo 0x58000000 > /sys/devices/system/memory/probe [ 29.151880] init_memory_mapping: [mem 0x58000000-0x5fffffff] # echo online_movable > /sys/devices/system/memory/memory11/state # echo online> /sys/devices/system/memory/memory8/state # echo online> /sys/devices/system/memory/memory10/state # echo offline> /sys/devices/system/memory/memory9/state [ 30.558819] Offlined Pages 32768 # free total used free shared buffers cached Mem: 780588 18014398509432020 830552 0 0 51180 -/+ buffers/cache: 18014398509380840 881732 Swap: 0 0 0 This is because the above commands probe higher memory after online a section with online_movable, which causes ZONE_HIGHMEM (or ZONE_NORMAL for systems without ZONE_HIGHMEM) overlaps ZONE_MOVABLE. After the second online_movable, the problem can be observed from zoneinfo: # cat /proc/zoneinfo ... Node 0, zone Movable pages free 65491 min 250 low 312 high 375 scanned 0 spanned 18446744073709518848 present 65536 managed 65536 ... This series of patches solve the problem by checking ZONE_MOVABLE when choosing zone for new memory. If new memory is inside or higher than ZONE_MOVABLE, makes it go there instead. After applying this series of patches, following are free and zoneinfo result (after offlining memory9): bash-4.2# free total used free shared buffers cached Mem: 780956 80112 700844 0 0 51180 -/+ buffers/cache: 28932 752024 Swap: 0 0 0 bash-4.2# cat /proc/zoneinfo Node 0, zone DMA pages free 3389 min 14 low 17 high 21 scanned 0 spanned 4095 present 3998 managed 3977 nr_free_pages 3389 ... start_pfn: 1 inactive_ratio: 1 Node 0, zone DMA32 pages free 73724 min 341 low 426 high 511 scanned 0 spanned 98304 present 98304 managed 92958 nr_free_pages 73724 ... start_pfn: 4096 inactive_ratio: 1 Node 0, zone Normal pages free 32630 min 120 low 150 high 180 scanned 0 spanned 32768 present 32768 managed 32768 nr_free_pages 32630 ... start_pfn: 262144 inactive_ratio: 1 Node 0, zone Movable pages free 65476 min 241 low 301 high 361 scanned 0 spanned 98304 present 65536 managed 65536 nr_free_pages 65476 ... start_pfn: 294912 inactive_ratio: 1 This patch (of 7): Introduce zone_for_memory() in arch independent code for arch_add_memory() use. Many arch_add_memory() function simply selects ZONE_HIGHMEM or ZONE_NORMAL and add new memory into it. However, with the existance of ZONE_MOVABLE, the selection method should be carefully considered: if new, higher memory is added after ZONE_MOVABLE is setup, the default zone and ZONE_MOVABLE may overlap each other. should_add_memory_movable() checks the status of ZONE_MOVABLE. If it has already contain memory, compare the address of new memory and movable memory. If new memory is higher than movable, it should be added into ZONE_MOVABLE instead of default zone. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Mel Gorman" <mgorman@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 23:07:36 +00:00
/*
* If movable zone has already been setup, newly added memory should be check.
* If its address is higher than movable zone, it should be added as movable.
* Without this check, movable zone may overlap with other zone.
*/
static int should_add_memory_movable(int nid, u64 start, u64 size)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
pg_data_t *pgdat = NODE_DATA(nid);
struct zone *movable_zone = pgdat->node_zones + ZONE_MOVABLE;
if (zone_is_empty(movable_zone))
return 0;
if (movable_zone->zone_start_pfn <= start_pfn)
return 1;
return 0;
}
int zone_for_memory(int nid, u64 start, u64 size, int zone_default,
bool for_device)
memory-hotplug: add zone_for_memory() for selecting zone for new memory This series of patches fixes a problem when adding memory in bad manner. For example: for a x86_64 machine booted with "mem=400M" and with 2GiB memory installed, following commands cause problem: # echo 0x40000000 > /sys/devices/system/memory/probe [ 28.613895] init_memory_mapping: [mem 0x40000000-0x47ffffff] # echo 0x48000000 > /sys/devices/system/memory/probe [ 28.693675] init_memory_mapping: [mem 0x48000000-0x4fffffff] # echo online_movable > /sys/devices/system/memory/memory9/state # echo 0x50000000 > /sys/devices/system/memory/probe [ 29.084090] init_memory_mapping: [mem 0x50000000-0x57ffffff] # echo 0x58000000 > /sys/devices/system/memory/probe [ 29.151880] init_memory_mapping: [mem 0x58000000-0x5fffffff] # echo online_movable > /sys/devices/system/memory/memory11/state # echo online> /sys/devices/system/memory/memory8/state # echo online> /sys/devices/system/memory/memory10/state # echo offline> /sys/devices/system/memory/memory9/state [ 30.558819] Offlined Pages 32768 # free total used free shared buffers cached Mem: 780588 18014398509432020 830552 0 0 51180 -/+ buffers/cache: 18014398509380840 881732 Swap: 0 0 0 This is because the above commands probe higher memory after online a section with online_movable, which causes ZONE_HIGHMEM (or ZONE_NORMAL for systems without ZONE_HIGHMEM) overlaps ZONE_MOVABLE. After the second online_movable, the problem can be observed from zoneinfo: # cat /proc/zoneinfo ... Node 0, zone Movable pages free 65491 min 250 low 312 high 375 scanned 0 spanned 18446744073709518848 present 65536 managed 65536 ... This series of patches solve the problem by checking ZONE_MOVABLE when choosing zone for new memory. If new memory is inside or higher than ZONE_MOVABLE, makes it go there instead. After applying this series of patches, following are free and zoneinfo result (after offlining memory9): bash-4.2# free total used free shared buffers cached Mem: 780956 80112 700844 0 0 51180 -/+ buffers/cache: 28932 752024 Swap: 0 0 0 bash-4.2# cat /proc/zoneinfo Node 0, zone DMA pages free 3389 min 14 low 17 high 21 scanned 0 spanned 4095 present 3998 managed 3977 nr_free_pages 3389 ... start_pfn: 1 inactive_ratio: 1 Node 0, zone DMA32 pages free 73724 min 341 low 426 high 511 scanned 0 spanned 98304 present 98304 managed 92958 nr_free_pages 73724 ... start_pfn: 4096 inactive_ratio: 1 Node 0, zone Normal pages free 32630 min 120 low 150 high 180 scanned 0 spanned 32768 present 32768 managed 32768 nr_free_pages 32630 ... start_pfn: 262144 inactive_ratio: 1 Node 0, zone Movable pages free 65476 min 241 low 301 high 361 scanned 0 spanned 98304 present 65536 managed 65536 nr_free_pages 65476 ... start_pfn: 294912 inactive_ratio: 1 This patch (of 7): Introduce zone_for_memory() in arch independent code for arch_add_memory() use. Many arch_add_memory() function simply selects ZONE_HIGHMEM or ZONE_NORMAL and add new memory into it. However, with the existance of ZONE_MOVABLE, the selection method should be carefully considered: if new, higher memory is added after ZONE_MOVABLE is setup, the default zone and ZONE_MOVABLE may overlap each other. should_add_memory_movable() checks the status of ZONE_MOVABLE. If it has already contain memory, compare the address of new memory and movable memory. If new memory is higher than movable, it should be added into ZONE_MOVABLE instead of default zone. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Mel Gorman" <mgorman@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 23:07:36 +00:00
{
#ifdef CONFIG_ZONE_DEVICE
if (for_device)
return ZONE_DEVICE;
#endif
memory-hotplug: add zone_for_memory() for selecting zone for new memory This series of patches fixes a problem when adding memory in bad manner. For example: for a x86_64 machine booted with "mem=400M" and with 2GiB memory installed, following commands cause problem: # echo 0x40000000 > /sys/devices/system/memory/probe [ 28.613895] init_memory_mapping: [mem 0x40000000-0x47ffffff] # echo 0x48000000 > /sys/devices/system/memory/probe [ 28.693675] init_memory_mapping: [mem 0x48000000-0x4fffffff] # echo online_movable > /sys/devices/system/memory/memory9/state # echo 0x50000000 > /sys/devices/system/memory/probe [ 29.084090] init_memory_mapping: [mem 0x50000000-0x57ffffff] # echo 0x58000000 > /sys/devices/system/memory/probe [ 29.151880] init_memory_mapping: [mem 0x58000000-0x5fffffff] # echo online_movable > /sys/devices/system/memory/memory11/state # echo online> /sys/devices/system/memory/memory8/state # echo online> /sys/devices/system/memory/memory10/state # echo offline> /sys/devices/system/memory/memory9/state [ 30.558819] Offlined Pages 32768 # free total used free shared buffers cached Mem: 780588 18014398509432020 830552 0 0 51180 -/+ buffers/cache: 18014398509380840 881732 Swap: 0 0 0 This is because the above commands probe higher memory after online a section with online_movable, which causes ZONE_HIGHMEM (or ZONE_NORMAL for systems without ZONE_HIGHMEM) overlaps ZONE_MOVABLE. After the second online_movable, the problem can be observed from zoneinfo: # cat /proc/zoneinfo ... Node 0, zone Movable pages free 65491 min 250 low 312 high 375 scanned 0 spanned 18446744073709518848 present 65536 managed 65536 ... This series of patches solve the problem by checking ZONE_MOVABLE when choosing zone for new memory. If new memory is inside or higher than ZONE_MOVABLE, makes it go there instead. After applying this series of patches, following are free and zoneinfo result (after offlining memory9): bash-4.2# free total used free shared buffers cached Mem: 780956 80112 700844 0 0 51180 -/+ buffers/cache: 28932 752024 Swap: 0 0 0 bash-4.2# cat /proc/zoneinfo Node 0, zone DMA pages free 3389 min 14 low 17 high 21 scanned 0 spanned 4095 present 3998 managed 3977 nr_free_pages 3389 ... start_pfn: 1 inactive_ratio: 1 Node 0, zone DMA32 pages free 73724 min 341 low 426 high 511 scanned 0 spanned 98304 present 98304 managed 92958 nr_free_pages 73724 ... start_pfn: 4096 inactive_ratio: 1 Node 0, zone Normal pages free 32630 min 120 low 150 high 180 scanned 0 spanned 32768 present 32768 managed 32768 nr_free_pages 32630 ... start_pfn: 262144 inactive_ratio: 1 Node 0, zone Movable pages free 65476 min 241 low 301 high 361 scanned 0 spanned 98304 present 65536 managed 65536 nr_free_pages 65476 ... start_pfn: 294912 inactive_ratio: 1 This patch (of 7): Introduce zone_for_memory() in arch independent code for arch_add_memory() use. Many arch_add_memory() function simply selects ZONE_HIGHMEM or ZONE_NORMAL and add new memory into it. However, with the existance of ZONE_MOVABLE, the selection method should be carefully considered: if new, higher memory is added after ZONE_MOVABLE is setup, the default zone and ZONE_MOVABLE may overlap each other. should_add_memory_movable() checks the status of ZONE_MOVABLE. If it has already contain memory, compare the address of new memory and movable memory. If new memory is higher than movable, it should be added into ZONE_MOVABLE instead of default zone. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: "Mel Gorman" <mgorman@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 23:07:36 +00:00
if (should_add_memory_movable(nid, start, size))
return ZONE_MOVABLE;
return zone_default;
}
/* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
int __ref add_memory_resource(int nid, struct resource *res)
{
u64 start, size;
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
pg_data_t *pgdat = NULL;
bool new_pgdat;
bool new_node;
int ret;
start = res->start;
size = resource_size(res);
ret = check_hotplug_memory_range(start, size);
if (ret)
return ret;
{ /* Stupid hack to suppress address-never-null warning */
void *p = NODE_DATA(nid);
new_pgdat = !p;
}
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
mem_hotplug_begin();
memory-hotplug: add hot-added memory ranges to memblock before allocate node_data for a node. Commit f9126ab9241f ("memory-hotplug: fix wrong edge when hot add a new node") hot-added memory range to memblock, after creating pgdat for new node. But there is a problem: add_memory() |--> hotadd_new_pgdat() |--> free_area_init_node() |--> get_pfn_range_for_nid() |--> find start_pfn and end_pfn in memblock |--> ...... |--> memblock_add_node(start, size, nid) -------- Here, just too late. get_pfn_range_for_nid() will find that start_pfn and end_pfn are both 0. As a result, when adding memory, dmesg will give the following wrong message. Initmem setup node 5 [mem 0x0000000000000000-0xffffffffffffffff] On node 5 totalpages: 0 Built 5 zonelists in Node order, mobility grouping on. Total pages: 32588823 Policy zone: Normal init_memory_mapping: [mem 0x60000000000-0x607ffffffff] The solution is simple, just add the memory range to memblock a little earlier, before hotadd_new_pgdat(). [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Gu Zheng <guz.fnst@cn.fujitsu.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: David Rientjes <rientjes@google.com> Cc: <stable@vger.kernel.org> [4.2.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 22:42:32 +00:00
/*
* Add new range to memblock so that when hotadd_new_pgdat() is called
* to allocate new pgdat, get_pfn_range_for_nid() will be able to find
* this new range and calculate total pages correctly. The range will
* be removed at hot-remove time.
*/
memblock_add_node(start, size, nid);
new_node = !node_online(nid);
if (new_node) {
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
pgdat = hotadd_new_pgdat(nid, start);
ret = -ENOMEM;
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
if (!pgdat)
goto error;
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
}
/* call arch's memory hotadd */
ret = arch_add_memory(nid, start, size, false);
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
if (ret < 0)
goto error;
/* we online node here. we can't roll back from here. */
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
node_set_online(nid);
if (new_node) {
ret = register_one_node(nid);
/*
* If sysfs file of new node can't create, cpu on the node
* can't be hot-added. There is no rollback way now.
* So, check by BUG_ON() to catch it reluctantly..
*/
BUG_ON(ret);
}
/* create new memmap entry */
firmware_map_add_hotplug(start, start + size, "System RAM");
goto out;
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
error:
/* rollback pgdat allocation and others */
if (new_pgdat)
rollback_node_hotadd(nid, pgdat);
memory-hotplug: add hot-added memory ranges to memblock before allocate node_data for a node. Commit f9126ab9241f ("memory-hotplug: fix wrong edge when hot add a new node") hot-added memory range to memblock, after creating pgdat for new node. But there is a problem: add_memory() |--> hotadd_new_pgdat() |--> free_area_init_node() |--> get_pfn_range_for_nid() |--> find start_pfn and end_pfn in memblock |--> ...... |--> memblock_add_node(start, size, nid) -------- Here, just too late. get_pfn_range_for_nid() will find that start_pfn and end_pfn are both 0. As a result, when adding memory, dmesg will give the following wrong message. Initmem setup node 5 [mem 0x0000000000000000-0xffffffffffffffff] On node 5 totalpages: 0 Built 5 zonelists in Node order, mobility grouping on. Total pages: 32588823 Policy zone: Normal init_memory_mapping: [mem 0x60000000000-0x607ffffffff] The solution is simple, just add the memory range to memblock a little earlier, before hotadd_new_pgdat(). [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Gu Zheng <guz.fnst@cn.fujitsu.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: David Rientjes <rientjes@google.com> Cc: <stable@vger.kernel.org> [4.2.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 22:42:32 +00:00
memblock_remove(start, size);
[PATCH] pgdat allocation for new node add (call pgdat allocation) Add node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is already merged in -mm due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:34 +00:00
out:
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
mem_hotplug_done();
return ret;
}
EXPORT_SYMBOL_GPL(add_memory_resource);
int __ref add_memory(int nid, u64 start, u64 size)
{
struct resource *res;
int ret;
res = register_memory_resource(start, size);
if (IS_ERR(res))
return PTR_ERR(res);
ret = add_memory_resource(nid, res);
if (ret < 0)
release_memory_resource(res);
return ret;
}
EXPORT_SYMBOL_GPL(add_memory);
#ifdef CONFIG_MEMORY_HOTREMOVE
memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 04:28:19 +00:00
/*
* A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
* set and the size of the free page is given by page_order(). Using this,
* the function determines if the pageblock contains only free pages.
* Due to buddy contraints, a free page at least the size of a pageblock will
* be located at the start of the pageblock
*/
static inline int pageblock_free(struct page *page)
{
return PageBuddy(page) && page_order(page) >= pageblock_order;
}
/* Return the start of the next active pageblock after a given page */
static struct page *next_active_pageblock(struct page *page)
{
/* Ensure the starting page is pageblock-aligned */
BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1));
/* If the entire pageblock is free, move to the end of free page */
if (pageblock_free(page)) {
int order;
/* be careful. we don't have locks, page_order can be changed.*/
order = page_order(page);
if ((order < MAX_ORDER) && (order >= pageblock_order))
return page + (1 << order);
}
memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 04:28:19 +00:00
return page + pageblock_nr_pages;
memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 04:28:19 +00:00
}
/* Checks if this range of memory is likely to be hot-removable. */
int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
{
struct page *page = pfn_to_page(start_pfn);
struct page *end_page = page + nr_pages;
/* Check the starting page of each pageblock within the range */
for (; page < end_page; page = next_active_pageblock(page)) {
if (!is_pageblock_removable_nolock(page))
memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 04:28:19 +00:00
return 0;
cond_resched();
memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 04:28:19 +00:00
}
/* All pageblocks in the memory block are likely to be hot-removable */
return 1;
}
/*
* Confirm all pages in a range [start, end) is belongs to the same zone.
*/
int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long pfn, sec_end_pfn;
struct zone *zone = NULL;
struct page *page;
int i;
for (pfn = start_pfn, sec_end_pfn = SECTION_ALIGN_UP(start_pfn);
pfn < end_pfn;
pfn = sec_end_pfn + 1, sec_end_pfn += PAGES_PER_SECTION) {
/* Make sure the memory section is present first */
if (!present_section_nr(pfn_to_section_nr(pfn)))
continue;
for (; pfn < sec_end_pfn && pfn < end_pfn;
pfn += MAX_ORDER_NR_PAGES) {
i = 0;
/* This is just a CONFIG_HOLES_IN_ZONE check.*/
while ((i < MAX_ORDER_NR_PAGES) &&
!pfn_valid_within(pfn + i))
i++;
if (i == MAX_ORDER_NR_PAGES)
continue;
page = pfn_to_page(pfn + i);
if (zone && page_zone(page) != zone)
return 0;
zone = page_zone(page);
}
}
return 1;
}
/*
mm: memory-hotplug: enable memory hotplug to handle hugepage Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:22:09 +00:00
* Scan pfn range [start,end) to find movable/migratable pages (LRU pages
* and hugepages). We scan pfn because it's much easier than scanning over
* linked list. This function returns the pfn of the first found movable
* page if it's found, otherwise 0.
*/
mm: memory-hotplug: enable memory hotplug to handle hugepage Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:22:09 +00:00
static unsigned long scan_movable_pages(unsigned long start, unsigned long end)
{
unsigned long pfn;
struct page *page;
for (pfn = start; pfn < end; pfn++) {
if (pfn_valid(pfn)) {
page = pfn_to_page(pfn);
if (PageLRU(page))
return pfn;
mm: memory-hotplug: enable memory hotplug to handle hugepage Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:22:09 +00:00
if (PageHuge(page)) {
if (page_huge_active(page))
mm: memory-hotplug: enable memory hotplug to handle hugepage Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:22:09 +00:00
return pfn;
else
pfn = round_up(pfn + 1,
1 << compound_order(page)) - 1;
}
}
}
return 0;
}
#define NR_OFFLINE_AT_ONCE_PAGES (256)
static int
do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long pfn;
struct page *page;
int move_pages = NR_OFFLINE_AT_ONCE_PAGES;
int not_managed = 0;
int ret = 0;
LIST_HEAD(source);
for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) {
if (!pfn_valid(pfn))
continue;
page = pfn_to_page(pfn);
mm: memory-hotplug: enable memory hotplug to handle hugepage Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:22:09 +00:00
if (PageHuge(page)) {
struct page *head = compound_head(page);
pfn = page_to_pfn(head) + (1<<compound_order(head)) - 1;
if (compound_order(head) > PFN_SECTION_SHIFT) {
ret = -EBUSY;
break;
}
if (isolate_huge_page(page, &source))
move_pages -= 1 << compound_order(head);
continue;
}
if (!get_page_unless_zero(page))
continue;
/*
* We can skip free pages. And we can only deal with pages on
* LRU.
*/
vmscan: move isolate_lru_page() to vmscan.c On large memory systems, the VM can spend way too much time scanning through pages that it cannot (or should not) evict from memory. Not only does it use up CPU time, but it also provokes lock contention and can leave large systems under memory presure in a catatonic state. This patch series improves VM scalability by: 1) putting filesystem backed, swap backed and unevictable pages onto their own LRUs, so the system only scans the pages that it can/should evict from memory 2) switching to two handed clock replacement for the anonymous LRUs, so the number of pages that need to be scanned when the system starts swapping is bound to a reasonable number 3) keeping unevictable pages off the LRU completely, so the VM does not waste CPU time scanning them. ramfs, ramdisk, SHM_LOCKED shared memory segments and mlock()ed VMA pages are keept on the unevictable list. This patch: isolate_lru_page logically belongs to be in vmscan.c than migrate.c. It is tough, because we don't need that function without memory migration so there is a valid argument to have it in migrate.c. However a subsequent patch needs to make use of it in the core mm, so we can happily move it to vmscan.c. Also, make the function a little more generic by not requiring that it adds an isolated page to a given list. Callers can do that. Note that we now have '__isolate_lru_page()', that does something quite different, visible outside of vmscan.c for use with memory controller. Methinks we need to rationalize these names/purposes. --lts [akpm@linux-foundation.org: fix mm/memory_hotplug.c build] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-19 03:26:09 +00:00
ret = isolate_lru_page(page);
if (!ret) { /* Success */
put_page(page);
vmscan: move isolate_lru_page() to vmscan.c On large memory systems, the VM can spend way too much time scanning through pages that it cannot (or should not) evict from memory. Not only does it use up CPU time, but it also provokes lock contention and can leave large systems under memory presure in a catatonic state. This patch series improves VM scalability by: 1) putting filesystem backed, swap backed and unevictable pages onto their own LRUs, so the system only scans the pages that it can/should evict from memory 2) switching to two handed clock replacement for the anonymous LRUs, so the number of pages that need to be scanned when the system starts swapping is bound to a reasonable number 3) keeping unevictable pages off the LRU completely, so the VM does not waste CPU time scanning them. ramfs, ramdisk, SHM_LOCKED shared memory segments and mlock()ed VMA pages are keept on the unevictable list. This patch: isolate_lru_page logically belongs to be in vmscan.c than migrate.c. It is tough, because we don't need that function without memory migration so there is a valid argument to have it in migrate.c. However a subsequent patch needs to make use of it in the core mm, so we can happily move it to vmscan.c. Also, make the function a little more generic by not requiring that it adds an isolated page to a given list. Callers can do that. Note that we now have '__isolate_lru_page()', that does something quite different, visible outside of vmscan.c for use with memory controller. Methinks we need to rationalize these names/purposes. --lts [akpm@linux-foundation.org: fix mm/memory_hotplug.c build] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-19 03:26:09 +00:00
list_add_tail(&page->lru, &source);
move_pages--;
inc_zone_page_state(page, NR_ISOLATED_ANON +
page_is_file_cache(page));
} else {
#ifdef CONFIG_DEBUG_VM
printk(KERN_ALERT "removing pfn %lx from LRU failed\n",
pfn);
dump_page(page, "failed to remove from LRU");
#endif
put_page(page);
/* Because we don't have big zone->lock. we should
check this again here. */
if (page_count(page)) {
not_managed++;
ret = -EBUSY;
break;
}
}
}
if (!list_empty(&source)) {
if (not_managed) {
mm: memory-hotplug: enable memory hotplug to handle hugepage Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:22:09 +00:00
putback_movable_pages(&source);
goto out;
}
memory-hotplug: don't replace lowmem pages with highmem The changelog for commit 6a6dccba2fdc ("mm: cma: don't replace lowmem pages with highmem") mentioned that lowmem pages can be replaced by highmem pages during CMA migration. 6a6dccba2fdc fixed that issue. Quote from that changelog: : The filesystem layer expects pages in the block device's mapping to not : be in highmem (the mapping's gfp mask is set in bdget()), but CMA can : currently replace lowmem pages with highmem pages, leading to crashes in : filesystem code such as the one below: : : Unable to handle kernel NULL pointer dereference at virtual address 00000400 : pgd = c0c98000 : [00000400] *pgd=00c91831, *pte=00000000, *ppte=00000000 : Internal error: Oops: 817 [#1] PREEMPT SMP ARM : CPU: 0 Not tainted (3.5.0-rc5+ #80) : PC is at __memzero+0x24/0x80 : ... : Process fsstress (pid: 323, stack limit = 0xc0cbc2f0) : Backtrace: : [<c010e3f0>] (ext4_getblk+0x0/0x180) from [<c010e58c>] (ext4_bread+0x1c/0x98) : [<c010e570>] (ext4_bread+0x0/0x98) from [<c0117944>] (ext4_mkdir+0x160/0x3bc) : r4:c15337f0 : [<c01177e4>] (ext4_mkdir+0x0/0x3bc) from [<c00c29e0>] (vfs_mkdir+0x8c/0x98) : [<c00c2954>] (vfs_mkdir+0x0/0x98) from [<c00c2a60>] (sys_mkdirat+0x74/0xac) : r6:00000000 r5:c152eb40 r4:000001ff r3:c14b43f0 : [<c00c29ec>] (sys_mkdirat+0x0/0xac) from [<c00c2ab8>] (sys_mkdir+0x20/0x24) : r6:beccdcf0 r5:00074000 r4:beccdbbc : [<c00c2a98>] (sys_mkdir+0x0/0x24) from [<c000e3c0>] (ret_fast_syscall+0x0/0x30) Memory-hotplug has same problem as CMA has so the same fix can be applied to memory-hotplug as well. Fix it by reusing. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-08 23:32:54 +00:00
/*
* alloc_migrate_target should be improooooved!!
* migrate_pages returns # of failed pages.
*/
ret = migrate_pages(&source, alloc_migrate_target, NULL, 0,
MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
if (ret)
mm: memory-hotplug: enable memory hotplug to handle hugepage Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:22:09 +00:00
putback_movable_pages(&source);
}
out:
return ret;
}
/*
* remove from free_area[] and mark all as Reserved.
*/
static int
offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
void *data)
{
__offline_isolated_pages(start, start + nr_pages);
return 0;
}
static void
offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
{
walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL,
offline_isolated_pages_cb);
}
/*
* Check all pages in range, recoreded as memory resource, are isolated.
*/
static int
check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
void *data)
{
int ret;
long offlined = *(long *)data;
ret = test_pages_isolated(start_pfn, start_pfn + nr_pages, true);
offlined = nr_pages;
if (!ret)
*(long *)data += offlined;
return ret;
}
static long
check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
{
long offlined = 0;
int ret;
ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined,
check_pages_isolated_cb);
if (ret < 0)
offlined = (long)ret;
return offlined;
}
#ifdef CONFIG_MOVABLE_NODE
/*
* When CONFIG_MOVABLE_NODE, we permit offlining of a node which doesn't have
* normal memory.
*/
static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
{
return true;
}
#else /* CONFIG_MOVABLE_NODE */
/* ensure the node has NORMAL memory if it is still online */
static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
{
struct pglist_data *pgdat = zone->zone_pgdat;
unsigned long present_pages = 0;
enum zone_type zt;
for (zt = 0; zt <= ZONE_NORMAL; zt++)
present_pages += pgdat->node_zones[zt].present_pages;
if (present_pages > nr_pages)
return true;
present_pages = 0;
for (; zt <= ZONE_MOVABLE; zt++)
present_pages += pgdat->node_zones[zt].present_pages;
/*
* we can't offline the last normal memory until all
* higher memory is offlined.
*/
return present_pages == 0;
}
#endif /* CONFIG_MOVABLE_NODE */
mem-hotplug: introduce movable_node boot option The hot-Pluggable field in SRAT specifies which memory is hotpluggable. As we mentioned before, if hotpluggable memory is used by the kernel, it cannot be hot-removed. So memory hotplug users may want to set all hotpluggable memory in ZONE_MOVABLE so that the kernel won't use it. Memory hotplug users may also set a node as movable node, which has ZONE_MOVABLE only, so that the whole node can be hot-removed. But the kernel cannot use memory in ZONE_MOVABLE. By doing this, the kernel cannot use memory in movable nodes. This will cause NUMA performance down. And other users may be unhappy. So we need a way to allow users to enable and disable this functionality. In this patch, we introduce movable_node boot option to allow users to choose to not to consume hotpluggable memory at early boot time and later we can set it as ZONE_MOVABLE. To achieve this, the movable_node boot option will control the memblock allocation direction. That said, after memblock is ready, before SRAT is parsed, we should allocate memory near the kernel image as we explained in the previous patches. So if movable_node boot option is set, the kernel does the following: 1. After memblock is ready, make memblock allocate memory bottom up. 2. After SRAT is parsed, make memblock behave as default, allocate memory top down. Users can specify "movable_node" in kernel commandline to enable this functionality. For those who don't use memory hotplug or who don't want to lose their NUMA performance, just don't specify anything. The kernel will work as before. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Suggested-by: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Suggested-by: Ingo Molnar <mingo@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-12 23:08:10 +00:00
static int __init cmdline_parse_movable_node(char *p)
{
#ifdef CONFIG_MOVABLE_NODE
/*
* Memory used by the kernel cannot be hot-removed because Linux
* cannot migrate the kernel pages. When memory hotplug is
* enabled, we should prevent memblock from allocating memory
* for the kernel.
*
* ACPI SRAT records all hotpluggable memory ranges. But before
* SRAT is parsed, we don't know about it.
*
* The kernel image is loaded into memory at very early time. We
* cannot prevent this anyway. So on NUMA system, we set any
* node the kernel resides in as un-hotpluggable.
*
* Since on modern servers, one node could have double-digit
* gigabytes memory, we can assume the memory around the kernel
* image is also un-hotpluggable. So before SRAT is parsed, just
* allocate memory near the kernel image to try the best to keep
* the kernel away from hotpluggable memory.
*/
memblock_set_bottom_up(true);
memblock, mem_hotplug: make memblock skip hotpluggable regions if needed Linux kernel cannot migrate pages used by the kernel. As a result, hotpluggable memory used by the kernel won't be able to be hot-removed. To solve this problem, the basic idea is to prevent memblock from allocating hotpluggable memory for the kernel at early time, and arrange all hotpluggable memory in ACPI SRAT(System Resource Affinity Table) as ZONE_MOVABLE when initializing zones. In the previous patches, we have marked hotpluggable memory regions with MEMBLOCK_HOTPLUG flag in memblock.memory. In this patch, we make memblock skip these hotpluggable memory regions in the default top-down allocation function if movable_node boot option is specified. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Rafael J . Wysocki" <rjw@sisk.pl> Cc: Chen Tang <imtangchen@gmail.com> Cc: Gong Chen <gong.chen@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Len Brown <lenb@kernel.org> Cc: Liu Jiang <jiang.liu@huawei.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Renninger <trenn@suse.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Vasilis Liaskovitis <vasilis.liaskovitis@profitbricks.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 23:49:35 +00:00
movable_node_enabled = true;
mem-hotplug: introduce movable_node boot option The hot-Pluggable field in SRAT specifies which memory is hotpluggable. As we mentioned before, if hotpluggable memory is used by the kernel, it cannot be hot-removed. So memory hotplug users may want to set all hotpluggable memory in ZONE_MOVABLE so that the kernel won't use it. Memory hotplug users may also set a node as movable node, which has ZONE_MOVABLE only, so that the whole node can be hot-removed. But the kernel cannot use memory in ZONE_MOVABLE. By doing this, the kernel cannot use memory in movable nodes. This will cause NUMA performance down. And other users may be unhappy. So we need a way to allow users to enable and disable this functionality. In this patch, we introduce movable_node boot option to allow users to choose to not to consume hotpluggable memory at early boot time and later we can set it as ZONE_MOVABLE. To achieve this, the movable_node boot option will control the memblock allocation direction. That said, after memblock is ready, before SRAT is parsed, we should allocate memory near the kernel image as we explained in the previous patches. So if movable_node boot option is set, the kernel does the following: 1. After memblock is ready, make memblock allocate memory bottom up. 2. After SRAT is parsed, make memblock behave as default, allocate memory top down. Users can specify "movable_node" in kernel commandline to enable this functionality. For those who don't use memory hotplug or who don't want to lose their NUMA performance, just don't specify anything. The kernel will work as before. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Suggested-by: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Suggested-by: Ingo Molnar <mingo@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-12 23:08:10 +00:00
#else
pr_warn("movable_node option not supported\n");
#endif
return 0;
}
early_param("movable_node", cmdline_parse_movable_node);
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
/* check which state of node_states will be changed when offline memory */
static void node_states_check_changes_offline(unsigned long nr_pages,
struct zone *zone, struct memory_notify *arg)
{
struct pglist_data *pgdat = zone->zone_pgdat;
unsigned long present_pages = 0;
enum zone_type zt, zone_last = ZONE_NORMAL;
/*
* If we have HIGHMEM or movable node, node_states[N_NORMAL_MEMORY]
* contains nodes which have zones of 0...ZONE_NORMAL,
* set zone_last to ZONE_NORMAL.
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
*
* If we don't have HIGHMEM nor movable node,
* node_states[N_NORMAL_MEMORY] contains nodes which have zones of
* 0...ZONE_MOVABLE, set zone_last to ZONE_MOVABLE.
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
*/
if (N_MEMORY == N_NORMAL_MEMORY)
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
zone_last = ZONE_MOVABLE;
/*
* check whether node_states[N_NORMAL_MEMORY] will be changed.
* If the memory to be offline is in a zone of 0...zone_last,
* and it is the last present memory, 0...zone_last will
* become empty after offline , thus we can determind we will
* need to clear the node from node_states[N_NORMAL_MEMORY].
*/
for (zt = 0; zt <= zone_last; zt++)
present_pages += pgdat->node_zones[zt].present_pages;
if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
arg->status_change_nid_normal = zone_to_nid(zone);
else
arg->status_change_nid_normal = -1;
#ifdef CONFIG_HIGHMEM
/*
* If we have movable node, node_states[N_HIGH_MEMORY]
* contains nodes which have zones of 0...ZONE_HIGHMEM,
* set zone_last to ZONE_HIGHMEM.
*
* If we don't have movable node, node_states[N_NORMAL_MEMORY]
* contains nodes which have zones of 0...ZONE_MOVABLE,
* set zone_last to ZONE_MOVABLE.
*/
zone_last = ZONE_HIGHMEM;
if (N_MEMORY == N_HIGH_MEMORY)
zone_last = ZONE_MOVABLE;
for (; zt <= zone_last; zt++)
present_pages += pgdat->node_zones[zt].present_pages;
if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
arg->status_change_nid_high = zone_to_nid(zone);
else
arg->status_change_nid_high = -1;
#else
arg->status_change_nid_high = arg->status_change_nid_normal;
#endif
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
/*
* node_states[N_HIGH_MEMORY] contains nodes which have 0...ZONE_MOVABLE
*/
zone_last = ZONE_MOVABLE;
/*
* check whether node_states[N_HIGH_MEMORY] will be changed
* If we try to offline the last present @nr_pages from the node,
* we can determind we will need to clear the node from
* node_states[N_HIGH_MEMORY].
*/
for (; zt <= zone_last; zt++)
present_pages += pgdat->node_zones[zt].present_pages;
if (nr_pages >= present_pages)
arg->status_change_nid = zone_to_nid(zone);
else
arg->status_change_nid = -1;
}
static void node_states_clear_node(int node, struct memory_notify *arg)
{
if (arg->status_change_nid_normal >= 0)
node_clear_state(node, N_NORMAL_MEMORY);
if ((N_MEMORY != N_NORMAL_MEMORY) &&
(arg->status_change_nid_high >= 0))
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
node_clear_state(node, N_HIGH_MEMORY);
if ((N_MEMORY != N_HIGH_MEMORY) &&
(arg->status_change_nid >= 0))
node_clear_state(node, N_MEMORY);
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
}
static int __ref __offline_pages(unsigned long start_pfn,
unsigned long end_pfn, unsigned long timeout)
{
unsigned long pfn, nr_pages, expire;
long offlined_pages;
int ret, drain, retry_max, node;
unsigned long flags;
struct zone *zone;
struct memory_notify arg;
/* at least, alignment against pageblock is necessary */
if (!IS_ALIGNED(start_pfn, pageblock_nr_pages))
return -EINVAL;
if (!IS_ALIGNED(end_pfn, pageblock_nr_pages))
return -EINVAL;
/* This makes hotplug much easier...and readable.
we assume this for now. .*/
if (!test_pages_in_a_zone(start_pfn, end_pfn))
return -EINVAL;
zone = page_zone(pfn_to_page(start_pfn));
node = zone_to_nid(zone);
nr_pages = end_pfn - start_pfn;
if (zone_idx(zone) <= ZONE_NORMAL && !can_offline_normal(zone, nr_pages))
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
return -EINVAL;
/* set above range as isolated */
ret = start_isolate_page_range(start_pfn, end_pfn,
MIGRATE_MOVABLE, true);
if (ret)
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
return ret;
arg.start_pfn = start_pfn;
arg.nr_pages = nr_pages;
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
node_states_check_changes_offline(nr_pages, zone, &arg);
ret = memory_notify(MEM_GOING_OFFLINE, &arg);
ret = notifier_to_errno(ret);
if (ret)
goto failed_removal;
pfn = start_pfn;
expire = jiffies + timeout;
drain = 0;
retry_max = 5;
repeat:
/* start memory hot removal */
ret = -EAGAIN;
if (time_after(jiffies, expire))
goto failed_removal;
ret = -EINTR;
if (signal_pending(current))
goto failed_removal;
ret = 0;
if (drain) {
lru_add_drain_all();
cond_resched();
drain_all_pages(zone);
}
mm: memory-hotplug: enable memory hotplug to handle hugepage Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:22:09 +00:00
pfn = scan_movable_pages(start_pfn, end_pfn);
if (pfn) { /* We have movable pages */
ret = do_migrate_range(pfn, end_pfn);
if (!ret) {
drain = 1;
goto repeat;
} else {
if (ret < 0)
if (--retry_max == 0)
goto failed_removal;
yield();
drain = 1;
goto repeat;
}
}
/* drain all zone's lru pagevec, this is asynchronous... */
lru_add_drain_all();
yield();
/* drain pcp pages, this is synchronous. */
drain_all_pages(zone);
mm: memory-hotplug: enable memory hotplug to handle hugepage Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:22:09 +00:00
/*
* dissolve free hugepages in the memory block before doing offlining
* actually in order to make hugetlbfs's object counting consistent.
*/
dissolve_free_huge_pages(start_pfn, end_pfn);
/* check again */
offlined_pages = check_pages_isolated(start_pfn, end_pfn);
if (offlined_pages < 0) {
ret = -EBUSY;
goto failed_removal;
}
printk(KERN_INFO "Offlined Pages %ld\n", offlined_pages);
/* Ok, all of our target is isolated.
We cannot do rollback at this point. */
offline_isolated_pages(start_pfn, end_pfn);
/* reset pagetype flags and makes migrate type to be MOVABLE */
undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
/* removal success */
mm: correctly update zone->managed_pages Enhance adjust_managed_page_count() to adjust totalhigh_pages for highmem pages. And change code which directly adjusts totalram_pages to use adjust_managed_page_count() because it adjusts totalram_pages, totalhigh_pages and zone->managed_pages altogether in a safe way. Remove inc_totalhigh_pages() and dec_totalhigh_pages() from xen/balloon driver bacause adjust_managed_page_count() has already adjusted totalhigh_pages. This patch also fixes two bugs: 1) enhances virtio_balloon driver to adjust totalhigh_pages when reserve/unreserve pages. 2) enhance memory_hotplug.c to adjust totalhigh_pages when hot-removing memory. We still need to deal with modifications of totalram_pages in file arch/powerpc/platforms/pseries/cmm.c, but need help from PPC experts. [akpm@linux-foundation.org: remove ifdef, per Wanpeng Li, virtio_balloon.c cleanup, per Sergei] [akpm@linux-foundation.org: export adjust_managed_page_count() to modules, for drivers/virtio/virtio_balloon.c] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 22:03:21 +00:00
adjust_managed_page_count(pfn_to_page(start_pfn), -offlined_pages);
zone->present_pages -= offlined_pages;
pgdat_resize_lock(zone->zone_pgdat, &flags);
zone->zone_pgdat->node_present_pages -= offlined_pages;
pgdat_resize_unlock(zone->zone_pgdat, &flags);
init_per_zone_wmark_min();
if (!populated_zone(zone)) {
zone_pcp_reset(zone);
mutex_lock(&zonelists_mutex);
build_all_zonelists(NULL, NULL);
mutex_unlock(&zonelists_mutex);
} else
zone_pcp_update(zone);
memory_hotplug: fix possible incorrect node_states[N_NORMAL_MEMORY] Currently memory_hotplug only manages the node_states[N_HIGH_MEMORY], it forgets to manage node_states[N_NORMAL_MEMORY]. This may cause node_states[N_NORMAL_MEMORY] to become incorrect. Example, if a node is empty before online, and we online a memory which is in ZONE_NORMAL. And after online, node_states[N_HIGH_MEMORY] is correct, but node_states[N_NORMAL_MEMORY] is incorrect, the online code doesn't set the new online node to node_states[N_NORMAL_MEMORY]. The same thing will happen when offlining (the offline code doesn't clear the node from node_states[N_NORMAL_MEMORY] when needed). Some memory managment code depends node_states[N_NORMAL_MEMORY], so we have to fix up the node_states[N_NORMAL_MEMORY]. We add node_states_check_changes_online() and node_states_check_changes_offline() to detect whether node_states[N_HIGH_MEMORY] and node_states[N_NORMAL_MEMORY] are changed while hotpluging. Also add @status_change_nid_normal to struct memory_notify, thus the memory hotplug callbacks know whether the node_states[N_NORMAL_MEMORY] are changed. (We can add a @flags and reuse @status_change_nid instead of introducing @status_change_nid_normal, but it will add much more complexity in memory hotplug callback in every subsystem. So introducing @status_change_nid_normal is better and it doesn't change the sematics of @status_change_nid) Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Rob Landley <rob@landley.net> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 00:01:03 +00:00
node_states_clear_node(node, &arg);
if (arg.status_change_nid >= 0)
kswapd_stop(node);
vm_total_pages = nr_free_pagecache_pages();
writeback_set_ratelimit();
memory_notify(MEM_OFFLINE, &arg);
return 0;
failed_removal:
printk(KERN_INFO "memory offlining [mem %#010llx-%#010llx] failed\n",
(unsigned long long) start_pfn << PAGE_SHIFT,
((unsigned long long) end_pfn << PAGE_SHIFT) - 1);
memory_notify(MEM_CANCEL_OFFLINE, &arg);
/* pushback to free area */
undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
return ret;
}
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 22:45:11 +00:00
/* Must be protected by mem_hotplug_begin() */
int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
{
return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ);
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
/**
* walk_memory_range - walks through all mem sections in [start_pfn, end_pfn)
* @start_pfn: start pfn of the memory range
* @end_pfn: end pfn of the memory range
* @arg: argument passed to func
* @func: callback for each memory section walked
*
* This function walks through all present mem sections in range
* [start_pfn, end_pfn) and call func on each mem section.
*
* Returns the return value of func.
*/
int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
void *arg, int (*func)(struct memory_block *, void *))
{
struct memory_block *mem = NULL;
struct mem_section *section;
unsigned long pfn, section_nr;
int ret;
for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
section_nr = pfn_to_section_nr(pfn);
if (!present_section_nr(section_nr))
continue;
section = __nr_to_section(section_nr);
/* same memblock? */
if (mem)
if ((section_nr >= mem->start_section_nr) &&
(section_nr <= mem->end_section_nr))
continue;
mem = find_memory_block_hinted(section, mem);
if (!mem)
continue;
ret = func(mem, arg);
if (ret) {
kobject_put(&mem->dev.kobj);
return ret;
}
}
if (mem)
kobject_put(&mem->dev.kobj);
return 0;
}
#ifdef CONFIG_MEMORY_HOTREMOVE
static int check_memblock_offlined_cb(struct memory_block *mem, void *arg)
{
int ret = !is_memblock_offlined(mem);
if (unlikely(ret)) {
phys_addr_t beginpa, endpa;
beginpa = PFN_PHYS(section_nr_to_pfn(mem->start_section_nr));
endpa = PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1;
pr_warn("removing memory fails, because memory "
"[%pa-%pa] is onlined\n",
&beginpa, &endpa);
}
return ret;
}
mm/hotplug: remove stop_machine() from try_offline_node() lock_device_hotplug() serializes hotplug & online/offline operations. The lock is held in common sysfs online/offline interfaces and ACPI hotplug code paths. And here are the code paths: - CPU & Mem online/offline via sysfs online store_online()->lock_device_hotplug() - Mem online via sysfs state: store_mem_state()->lock_device_hotplug() - ACPI CPU & Mem hot-add: acpi_scan_bus_device_check()->lock_device_hotplug() - ACPI CPU & Mem hot-delete: acpi_scan_hot_remove()->lock_device_hotplug() try_offline_node() off-lines a node if all memory sections and cpus are removed on the node. It is called from acpi_processor_remove() and acpi_memory_remove_memory()->remove_memory() paths, both of which are in the ACPI hotplug code. try_offline_node() calls stop_machine() to stop all cpus while checking all cpu status with the assumption that the caller is not protected from CPU hotplug or CPU online/offline operations. However, the caller is always serialized with lock_device_hotplug(). Also, the code needs to be properly serialized with a lock, not by stopping all cpus at a random place with stop_machine(). This patch removes the use of stop_machine() in try_offline_node() and adds comments to try_offline_node() and remove_memory() that lock_device_hotplug() is required. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:21:50 +00:00
static int check_cpu_on_node(pg_data_t *pgdat)
{
int cpu;
for_each_present_cpu(cpu) {
if (cpu_to_node(cpu) == pgdat->node_id)
/*
* the cpu on this node isn't removed, and we can't
* offline this node.
*/
return -EBUSY;
}
return 0;
}
mm/hotplug: remove stop_machine() from try_offline_node() lock_device_hotplug() serializes hotplug & online/offline operations. The lock is held in common sysfs online/offline interfaces and ACPI hotplug code paths. And here are the code paths: - CPU & Mem online/offline via sysfs online store_online()->lock_device_hotplug() - Mem online via sysfs state: store_mem_state()->lock_device_hotplug() - ACPI CPU & Mem hot-add: acpi_scan_bus_device_check()->lock_device_hotplug() - ACPI CPU & Mem hot-delete: acpi_scan_hot_remove()->lock_device_hotplug() try_offline_node() off-lines a node if all memory sections and cpus are removed on the node. It is called from acpi_processor_remove() and acpi_memory_remove_memory()->remove_memory() paths, both of which are in the ACPI hotplug code. try_offline_node() calls stop_machine() to stop all cpus while checking all cpu status with the assumption that the caller is not protected from CPU hotplug or CPU online/offline operations. However, the caller is always serialized with lock_device_hotplug(). Also, the code needs to be properly serialized with a lock, not by stopping all cpus at a random place with stop_machine(). This patch removes the use of stop_machine() in try_offline_node() and adds comments to try_offline_node() and remove_memory() that lock_device_hotplug() is required. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:21:50 +00:00
static void unmap_cpu_on_node(pg_data_t *pgdat)
{
#ifdef CONFIG_ACPI_NUMA
int cpu;
for_each_possible_cpu(cpu)
if (cpu_to_node(cpu) == pgdat->node_id)
numa_clear_node(cpu);
#endif
}
mm/hotplug: remove stop_machine() from try_offline_node() lock_device_hotplug() serializes hotplug & online/offline operations. The lock is held in common sysfs online/offline interfaces and ACPI hotplug code paths. And here are the code paths: - CPU & Mem online/offline via sysfs online store_online()->lock_device_hotplug() - Mem online via sysfs state: store_mem_state()->lock_device_hotplug() - ACPI CPU & Mem hot-add: acpi_scan_bus_device_check()->lock_device_hotplug() - ACPI CPU & Mem hot-delete: acpi_scan_hot_remove()->lock_device_hotplug() try_offline_node() off-lines a node if all memory sections and cpus are removed on the node. It is called from acpi_processor_remove() and acpi_memory_remove_memory()->remove_memory() paths, both of which are in the ACPI hotplug code. try_offline_node() calls stop_machine() to stop all cpus while checking all cpu status with the assumption that the caller is not protected from CPU hotplug or CPU online/offline operations. However, the caller is always serialized with lock_device_hotplug(). Also, the code needs to be properly serialized with a lock, not by stopping all cpus at a random place with stop_machine(). This patch removes the use of stop_machine() in try_offline_node() and adds comments to try_offline_node() and remove_memory() that lock_device_hotplug() is required. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:21:50 +00:00
static int check_and_unmap_cpu_on_node(pg_data_t *pgdat)
{
mm/hotplug: remove stop_machine() from try_offline_node() lock_device_hotplug() serializes hotplug & online/offline operations. The lock is held in common sysfs online/offline interfaces and ACPI hotplug code paths. And here are the code paths: - CPU & Mem online/offline via sysfs online store_online()->lock_device_hotplug() - Mem online via sysfs state: store_mem_state()->lock_device_hotplug() - ACPI CPU & Mem hot-add: acpi_scan_bus_device_check()->lock_device_hotplug() - ACPI CPU & Mem hot-delete: acpi_scan_hot_remove()->lock_device_hotplug() try_offline_node() off-lines a node if all memory sections and cpus are removed on the node. It is called from acpi_processor_remove() and acpi_memory_remove_memory()->remove_memory() paths, both of which are in the ACPI hotplug code. try_offline_node() calls stop_machine() to stop all cpus while checking all cpu status with the assumption that the caller is not protected from CPU hotplug or CPU online/offline operations. However, the caller is always serialized with lock_device_hotplug(). Also, the code needs to be properly serialized with a lock, not by stopping all cpus at a random place with stop_machine(). This patch removes the use of stop_machine() in try_offline_node() and adds comments to try_offline_node() and remove_memory() that lock_device_hotplug() is required. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:21:50 +00:00
int ret;
mm/hotplug: remove stop_machine() from try_offline_node() lock_device_hotplug() serializes hotplug & online/offline operations. The lock is held in common sysfs online/offline interfaces and ACPI hotplug code paths. And here are the code paths: - CPU & Mem online/offline via sysfs online store_online()->lock_device_hotplug() - Mem online via sysfs state: store_mem_state()->lock_device_hotplug() - ACPI CPU & Mem hot-add: acpi_scan_bus_device_check()->lock_device_hotplug() - ACPI CPU & Mem hot-delete: acpi_scan_hot_remove()->lock_device_hotplug() try_offline_node() off-lines a node if all memory sections and cpus are removed on the node. It is called from acpi_processor_remove() and acpi_memory_remove_memory()->remove_memory() paths, both of which are in the ACPI hotplug code. try_offline_node() calls stop_machine() to stop all cpus while checking all cpu status with the assumption that the caller is not protected from CPU hotplug or CPU online/offline operations. However, the caller is always serialized with lock_device_hotplug(). Also, the code needs to be properly serialized with a lock, not by stopping all cpus at a random place with stop_machine(). This patch removes the use of stop_machine() in try_offline_node() and adds comments to try_offline_node() and remove_memory() that lock_device_hotplug() is required. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:21:50 +00:00
ret = check_cpu_on_node(pgdat);
if (ret)
return ret;
/*
* the node will be offlined when we come here, so we can clear
* the cpu_to_node() now.
*/
mm/hotplug: remove stop_machine() from try_offline_node() lock_device_hotplug() serializes hotplug & online/offline operations. The lock is held in common sysfs online/offline interfaces and ACPI hotplug code paths. And here are the code paths: - CPU & Mem online/offline via sysfs online store_online()->lock_device_hotplug() - Mem online via sysfs state: store_mem_state()->lock_device_hotplug() - ACPI CPU & Mem hot-add: acpi_scan_bus_device_check()->lock_device_hotplug() - ACPI CPU & Mem hot-delete: acpi_scan_hot_remove()->lock_device_hotplug() try_offline_node() off-lines a node if all memory sections and cpus are removed on the node. It is called from acpi_processor_remove() and acpi_memory_remove_memory()->remove_memory() paths, both of which are in the ACPI hotplug code. try_offline_node() calls stop_machine() to stop all cpus while checking all cpu status with the assumption that the caller is not protected from CPU hotplug or CPU online/offline operations. However, the caller is always serialized with lock_device_hotplug(). Also, the code needs to be properly serialized with a lock, not by stopping all cpus at a random place with stop_machine(). This patch removes the use of stop_machine() in try_offline_node() and adds comments to try_offline_node() and remove_memory() that lock_device_hotplug() is required. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:21:50 +00:00
unmap_cpu_on_node(pgdat);
return 0;
}
mm/hotplug: remove stop_machine() from try_offline_node() lock_device_hotplug() serializes hotplug & online/offline operations. The lock is held in common sysfs online/offline interfaces and ACPI hotplug code paths. And here are the code paths: - CPU & Mem online/offline via sysfs online store_online()->lock_device_hotplug() - Mem online via sysfs state: store_mem_state()->lock_device_hotplug() - ACPI CPU & Mem hot-add: acpi_scan_bus_device_check()->lock_device_hotplug() - ACPI CPU & Mem hot-delete: acpi_scan_hot_remove()->lock_device_hotplug() try_offline_node() off-lines a node if all memory sections and cpus are removed on the node. It is called from acpi_processor_remove() and acpi_memory_remove_memory()->remove_memory() paths, both of which are in the ACPI hotplug code. try_offline_node() calls stop_machine() to stop all cpus while checking all cpu status with the assumption that the caller is not protected from CPU hotplug or CPU online/offline operations. However, the caller is always serialized with lock_device_hotplug(). Also, the code needs to be properly serialized with a lock, not by stopping all cpus at a random place with stop_machine(). This patch removes the use of stop_machine() in try_offline_node() and adds comments to try_offline_node() and remove_memory() that lock_device_hotplug() is required. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:21:50 +00:00
/**
* try_offline_node
*
* Offline a node if all memory sections and cpus of the node are removed.
*
* NOTE: The caller must call lock_device_hotplug() to serialize hotplug
* and online/offline operations before this call.
*/
void try_offline_node(int nid)
{
pg_data_t *pgdat = NODE_DATA(nid);
unsigned long start_pfn = pgdat->node_start_pfn;
unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
unsigned long pfn;
int i;
for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
unsigned long section_nr = pfn_to_section_nr(pfn);
if (!present_section_nr(section_nr))
continue;
if (pfn_to_nid(pfn) != nid)
continue;
/*
* some memory sections of this node are not removed, and we
* can't offline node now.
*/
return;
}
mm/hotplug: remove stop_machine() from try_offline_node() lock_device_hotplug() serializes hotplug & online/offline operations. The lock is held in common sysfs online/offline interfaces and ACPI hotplug code paths. And here are the code paths: - CPU & Mem online/offline via sysfs online store_online()->lock_device_hotplug() - Mem online via sysfs state: store_mem_state()->lock_device_hotplug() - ACPI CPU & Mem hot-add: acpi_scan_bus_device_check()->lock_device_hotplug() - ACPI CPU & Mem hot-delete: acpi_scan_hot_remove()->lock_device_hotplug() try_offline_node() off-lines a node if all memory sections and cpus are removed on the node. It is called from acpi_processor_remove() and acpi_memory_remove_memory()->remove_memory() paths, both of which are in the ACPI hotplug code. try_offline_node() calls stop_machine() to stop all cpus while checking all cpu status with the assumption that the caller is not protected from CPU hotplug or CPU online/offline operations. However, the caller is always serialized with lock_device_hotplug(). Also, the code needs to be properly serialized with a lock, not by stopping all cpus at a random place with stop_machine(). This patch removes the use of stop_machine() in try_offline_node() and adds comments to try_offline_node() and remove_memory() that lock_device_hotplug() is required. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:21:50 +00:00
if (check_and_unmap_cpu_on_node(pgdat))
return;
/*
* all memory/cpu of this node are removed, we can offline this
* node now.
*/
node_set_offline(nid);
unregister_one_node(nid);
/* free waittable in each zone */
for (i = 0; i < MAX_NR_ZONES; i++) {
struct zone *zone = pgdat->node_zones + i;
/*
* wait_table may be allocated from boot memory,
* here only free if it's allocated by vmalloc.
*/
mm/memory_hotplug.c: set zone->wait_table to null after freeing it Izumi found the following oops when hot re-adding a node: BUG: unable to handle kernel paging request at ffffc90008963690 IP: __wake_up_bit+0x20/0x70 Oops: 0000 [#1] SMP CPU: 68 PID: 1237 Comm: rs:main Q:Reg Not tainted 4.1.0-rc5 #80 Hardware name: FUJITSU PRIMEQUEST2800E/SB, BIOS PRIMEQUEST 2000 Series BIOS Version 1.87 04/28/2015 task: ffff880838df8000 ti: ffff880017b94000 task.ti: ffff880017b94000 RIP: 0010:[<ffffffff810dff80>] [<ffffffff810dff80>] __wake_up_bit+0x20/0x70 RSP: 0018:ffff880017b97be8 EFLAGS: 00010246 RAX: ffffc90008963690 RBX: 00000000003c0000 RCX: 000000000000a4c9 RDX: 0000000000000000 RSI: ffffea101bffd500 RDI: ffffc90008963648 RBP: ffff880017b97c08 R08: 0000000002000020 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8a0797c73800 R13: ffffea101bffd500 R14: 0000000000000001 R15: 00000000003c0000 FS: 00007fcc7ffff700(0000) GS:ffff880874800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90008963690 CR3: 0000000836761000 CR4: 00000000001407e0 Call Trace: unlock_page+0x6d/0x70 generic_write_end+0x53/0xb0 xfs_vm_write_end+0x29/0x80 [xfs] generic_perform_write+0x10a/0x1e0 xfs_file_buffered_aio_write+0x14d/0x3e0 [xfs] xfs_file_write_iter+0x79/0x120 [xfs] __vfs_write+0xd4/0x110 vfs_write+0xac/0x1c0 SyS_write+0x58/0xd0 system_call_fastpath+0x12/0x76 Code: 5d c3 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 48 83 ec 20 65 48 8b 04 25 28 00 00 00 48 89 45 f8 31 c0 48 8d 47 48 <48> 39 47 48 48 c7 45 e8 00 00 00 00 48 c7 45 f0 00 00 00 00 48 RIP [<ffffffff810dff80>] __wake_up_bit+0x20/0x70 RSP <ffff880017b97be8> CR2: ffffc90008963690 Reproduce method (re-add a node):: Hot-add nodeA --> remove nodeA --> hot-add nodeA (panic) This seems an use-after-free problem, and the root cause is zone->wait_table was not set to *NULL* after free it in try_offline_node. When hot re-add a node, we will reuse the pgdat of it, so does the zone struct, and when add pages to the target zone, it will init the zone first (including the wait_table) if the zone is not initialized. The judgement of zone initialized is based on zone->wait_table: static inline bool zone_is_initialized(struct zone *zone) { return !!zone->wait_table; } so if we do not set the zone->wait_table to *NULL* after free it, the memory hotplug routine will skip the init of new zone when hot re-add the node, and the wait_table still points to the freed memory, then we will access the invalid address when trying to wake up the waiting people after the i/o operation with the page is done, such as mentioned above. Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Reported-by: Taku Izumi <izumi.taku@jp.fujitsu.com> Reviewed by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-10 18:14:43 +00:00
if (is_vmalloc_addr(zone->wait_table)) {
vfree(zone->wait_table);
mm/memory_hotplug.c: set zone->wait_table to null after freeing it Izumi found the following oops when hot re-adding a node: BUG: unable to handle kernel paging request at ffffc90008963690 IP: __wake_up_bit+0x20/0x70 Oops: 0000 [#1] SMP CPU: 68 PID: 1237 Comm: rs:main Q:Reg Not tainted 4.1.0-rc5 #80 Hardware name: FUJITSU PRIMEQUEST2800E/SB, BIOS PRIMEQUEST 2000 Series BIOS Version 1.87 04/28/2015 task: ffff880838df8000 ti: ffff880017b94000 task.ti: ffff880017b94000 RIP: 0010:[<ffffffff810dff80>] [<ffffffff810dff80>] __wake_up_bit+0x20/0x70 RSP: 0018:ffff880017b97be8 EFLAGS: 00010246 RAX: ffffc90008963690 RBX: 00000000003c0000 RCX: 000000000000a4c9 RDX: 0000000000000000 RSI: ffffea101bffd500 RDI: ffffc90008963648 RBP: ffff880017b97c08 R08: 0000000002000020 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8a0797c73800 R13: ffffea101bffd500 R14: 0000000000000001 R15: 00000000003c0000 FS: 00007fcc7ffff700(0000) GS:ffff880874800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90008963690 CR3: 0000000836761000 CR4: 00000000001407e0 Call Trace: unlock_page+0x6d/0x70 generic_write_end+0x53/0xb0 xfs_vm_write_end+0x29/0x80 [xfs] generic_perform_write+0x10a/0x1e0 xfs_file_buffered_aio_write+0x14d/0x3e0 [xfs] xfs_file_write_iter+0x79/0x120 [xfs] __vfs_write+0xd4/0x110 vfs_write+0xac/0x1c0 SyS_write+0x58/0xd0 system_call_fastpath+0x12/0x76 Code: 5d c3 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 48 83 ec 20 65 48 8b 04 25 28 00 00 00 48 89 45 f8 31 c0 48 8d 47 48 <48> 39 47 48 48 c7 45 e8 00 00 00 00 48 c7 45 f0 00 00 00 00 48 RIP [<ffffffff810dff80>] __wake_up_bit+0x20/0x70 RSP <ffff880017b97be8> CR2: ffffc90008963690 Reproduce method (re-add a node):: Hot-add nodeA --> remove nodeA --> hot-add nodeA (panic) This seems an use-after-free problem, and the root cause is zone->wait_table was not set to *NULL* after free it in try_offline_node. When hot re-add a node, we will reuse the pgdat of it, so does the zone struct, and when add pages to the target zone, it will init the zone first (including the wait_table) if the zone is not initialized. The judgement of zone initialized is based on zone->wait_table: static inline bool zone_is_initialized(struct zone *zone) { return !!zone->wait_table; } so if we do not set the zone->wait_table to *NULL* after free it, the memory hotplug routine will skip the init of new zone when hot re-add the node, and the wait_table still points to the freed memory, then we will access the invalid address when trying to wake up the waiting people after the i/o operation with the page is done, such as mentioned above. Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Reported-by: Taku Izumi <izumi.taku@jp.fujitsu.com> Reviewed by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-10 18:14:43 +00:00
zone->wait_table = NULL;
}
}
}
EXPORT_SYMBOL(try_offline_node);
mm/hotplug: remove stop_machine() from try_offline_node() lock_device_hotplug() serializes hotplug & online/offline operations. The lock is held in common sysfs online/offline interfaces and ACPI hotplug code paths. And here are the code paths: - CPU & Mem online/offline via sysfs online store_online()->lock_device_hotplug() - Mem online via sysfs state: store_mem_state()->lock_device_hotplug() - ACPI CPU & Mem hot-add: acpi_scan_bus_device_check()->lock_device_hotplug() - ACPI CPU & Mem hot-delete: acpi_scan_hot_remove()->lock_device_hotplug() try_offline_node() off-lines a node if all memory sections and cpus are removed on the node. It is called from acpi_processor_remove() and acpi_memory_remove_memory()->remove_memory() paths, both of which are in the ACPI hotplug code. try_offline_node() calls stop_machine() to stop all cpus while checking all cpu status with the assumption that the caller is not protected from CPU hotplug or CPU online/offline operations. However, the caller is always serialized with lock_device_hotplug(). Also, the code needs to be properly serialized with a lock, not by stopping all cpus at a random place with stop_machine(). This patch removes the use of stop_machine() in try_offline_node() and adds comments to try_offline_node() and remove_memory() that lock_device_hotplug() is required. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:21:50 +00:00
/**
* remove_memory
*
* NOTE: The caller must call lock_device_hotplug() to serialize hotplug
* and online/offline operations before this call, as required by
* try_offline_node().
*/
void __ref remove_memory(int nid, u64 start, u64 size)
{
int ret;
memory-hotplug: try to offline the memory twice to avoid dependence memory can't be offlined when CONFIG_MEMCG is selected. For example: there is a memory device on node 1. The address range is [1G, 1.5G). You will find 4 new directories memory8, memory9, memory10, and memory11 under the directory /sys/devices/system/memory/. If CONFIG_MEMCG is selected, we will allocate memory to store page cgroup when we online pages. When we online memory8, the memory stored page cgroup is not provided by this memory device. But when we online memory9, the memory stored page cgroup may be provided by memory8. So we can't offline memory8 now. We should offline the memory in the reversed order. When the memory device is hotremoved, we will auto offline memory provided by this memory device. But we don't know which memory is onlined first, so offlining memory may fail. In such case, iterate twice to offline the memory. 1st iterate: offline every non primary memory block. 2nd iterate: offline primary (i.e. first added) memory block. This idea is suggested by KOSAKI Motohiro. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Wu Jianguo <wujianguo@huawei.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:32:50 +00:00
BUG_ON(check_hotplug_memory_range(start, size));
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
mem_hotplug_begin();
memory-hotplug: check whether all memory blocks are offlined or not when removing memory We remove the memory like this: 1. lock memory hotplug 2. offline a memory block 3. unlock memory hotplug 4. repeat 1-3 to offline all memory blocks 5. lock memory hotplug 6. remove memory(TODO) 7. unlock memory hotplug All memory blocks must be offlined before removing memory. But we don't hold the lock in the whole operation. So we should check whether all memory blocks are offlined before step6. Otherwise, kernel maybe panicked. Offlining a memory block and removing a memory device can be two different operations. Users can just offline some memory blocks without removing the memory device. For this purpose, the kernel has held lock_memory_hotplug() in __offline_pages(). To reuse the code for memory hot-remove, we repeat step 1-3 to offline all the memory blocks, repeatedly lock and unlock memory hotplug, but not hold the memory hotplug lock in the whole operation. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Wu Jianguo <wujianguo@huawei.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:32:52 +00:00
/*
* All memory blocks must be offlined before removing memory. Check
* whether all memory blocks in question are offline and trigger a BUG()
* if this is not the case.
memory-hotplug: check whether all memory blocks are offlined or not when removing memory We remove the memory like this: 1. lock memory hotplug 2. offline a memory block 3. unlock memory hotplug 4. repeat 1-3 to offline all memory blocks 5. lock memory hotplug 6. remove memory(TODO) 7. unlock memory hotplug All memory blocks must be offlined before removing memory. But we don't hold the lock in the whole operation. So we should check whether all memory blocks are offlined before step6. Otherwise, kernel maybe panicked. Offlining a memory block and removing a memory device can be two different operations. Users can just offline some memory blocks without removing the memory device. For this purpose, the kernel has held lock_memory_hotplug() in __offline_pages(). To reuse the code for memory hot-remove, we repeat step 1-3 to offline all the memory blocks, repeatedly lock and unlock memory hotplug, but not hold the memory hotplug lock in the whole operation. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Wu Jianguo <wujianguo@huawei.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:32:52 +00:00
*/
ret = walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), NULL,
check_memblock_offlined_cb);
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
if (ret)
BUG();
memory-hotplug: check whether all memory blocks are offlined or not when removing memory We remove the memory like this: 1. lock memory hotplug 2. offline a memory block 3. unlock memory hotplug 4. repeat 1-3 to offline all memory blocks 5. lock memory hotplug 6. remove memory(TODO) 7. unlock memory hotplug All memory blocks must be offlined before removing memory. But we don't hold the lock in the whole operation. So we should check whether all memory blocks are offlined before step6. Otherwise, kernel maybe panicked. Offlining a memory block and removing a memory device can be two different operations. Users can just offline some memory blocks without removing the memory device. For this purpose, the kernel has held lock_memory_hotplug() in __offline_pages(). To reuse the code for memory hot-remove, we repeat step 1-3 to offline all the memory blocks, repeatedly lock and unlock memory hotplug, but not hold the memory hotplug lock in the whole operation. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Wu Jianguo <wujianguo@huawei.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:32:52 +00:00
memory-hotplug: remove /sys/firmware/memmap/X sysfs When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type} sysfs files are created. But there is no code to remove these files. This patch implements the function to remove them. We cannot free firmware_map_entry which is allocated by bootmem because there is no way to do so when the system is up. But we can at least remember the address of that memory and reuse the storage when the memory is added next time. This patch also introduces a new list map_entries_bootmem to link the map entries allocated by bootmem when they are removed, and a lock to protect it. And these entries will be reused when the memory is hot-added again. The idea is suggestted by Andrew Morton. NOTE: It is unsafe to return an entry pointer and release the map_entries_lock. So we should not hold the map_entries_lock separately in firmware_map_find_entry() and firmware_map_remove_entry(). Hold the map_entries_lock across find and remove /sys/firmware/memmap/X operation. And also, users of these two functions need to be careful to hold the lock when using these two functions. [tangchen@cn.fujitsu.com: Hold spinlock across find|remove /sys operation] [tangchen@cn.fujitsu.com: fix the wrong comments of map_entries] [tangchen@cn.fujitsu.com: reuse the storage of /sys/firmware/memmap/X/ allocated by bootmem] [tangchen@cn.fujitsu.com: fix section mismatch problem] [tangchen@cn.fujitsu.com: fix the doc format in drivers/firmware/memmap.c] Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Julian Calaby <julian.calaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:32:56 +00:00
/* remove memmap entry */
firmware_map_remove(start, start + size, "System RAM");
memblock_free(start, size);
memblock_remove(start, size);
memory-hotplug: remove /sys/firmware/memmap/X sysfs When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type} sysfs files are created. But there is no code to remove these files. This patch implements the function to remove them. We cannot free firmware_map_entry which is allocated by bootmem because there is no way to do so when the system is up. But we can at least remember the address of that memory and reuse the storage when the memory is added next time. This patch also introduces a new list map_entries_bootmem to link the map entries allocated by bootmem when they are removed, and a lock to protect it. And these entries will be reused when the memory is hot-added again. The idea is suggestted by Andrew Morton. NOTE: It is unsafe to return an entry pointer and release the map_entries_lock. So we should not hold the map_entries_lock separately in firmware_map_find_entry() and firmware_map_remove_entry(). Hold the map_entries_lock across find and remove /sys/firmware/memmap/X operation. And also, users of these two functions need to be careful to hold the lock when using these two functions. [tangchen@cn.fujitsu.com: Hold spinlock across find|remove /sys operation] [tangchen@cn.fujitsu.com: fix the wrong comments of map_entries] [tangchen@cn.fujitsu.com: reuse the storage of /sys/firmware/memmap/X/ allocated by bootmem] [tangchen@cn.fujitsu.com: fix section mismatch problem] [tangchen@cn.fujitsu.com: fix the doc format in drivers/firmware/memmap.c] Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Julian Calaby <julian.calaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:32:56 +00:00
arch_remove_memory(start, size);
try_offline_node(nid);
mem-hotplug: implement get/put_online_mems kmem_cache_{create,destroy,shrink} need to get a stable value of cpu/node online mask, because they init/destroy/access per-cpu/node kmem_cache parts, which can be allocated or destroyed on cpu/mem hotplug. To protect against cpu hotplug, these functions use {get,put}_online_cpus. However, they do nothing to synchronize with memory hotplug - taking the slab_mutex does not eliminate the possibility of race as described in patch 2. What we need there is something like get_online_cpus, but for memory. We already have lock_memory_hotplug, which serves for the purpose, but it's a bit of a hammer right now, because it's backed by a mutex. As a result, it imposes some limitations to locking order, which are not desirable, and can't be used just like get_online_cpus. That's why in patch 1 I substitute it with get/put_online_mems, which work exactly like get/put_online_cpus except they block not cpu, but memory hotplug. [ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by myself, because it used an rw semaphore for get/put_online_mems, making them dead lock prune. ] This patch (of 2): {un}lock_memory_hotplug, which is used to synchronize against memory hotplug, is currently backed by a mutex, which makes it a bit of a hammer - threads that only want to get a stable value of online nodes mask won't be able to proceed concurrently. Also, it imposes some strong locking ordering rules on it, which narrows down the set of its usage scenarios. This patch introduces get/put_online_mems, which are the same as get/put_online_cpus, but for memory hotplug, i.e. executing a code inside a get/put_online_mems section will guarantee a stable value of online nodes, present pages, etc. lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:07:18 +00:00
mem_hotplug_done();
}
EXPORT_SYMBOL_GPL(remove_memory);
#endif /* CONFIG_MEMORY_HOTREMOVE */