linux/mm
Vlastimil Babka e500059ba5 mm, slub: move disabling/enabling irqs to ___slab_alloc()
Currently __slab_alloc() disables irqs around the whole ___slab_alloc().  This
includes cases where this is not needed, such as when the allocation ends up in
the page allocator and has to awkwardly enable irqs back based on gfp flags.
Also the whole kmem_cache_alloc_bulk() is executed with irqs disabled even when
it hits the __slab_alloc() slow path, and long periods with disabled interrupts
are undesirable.

As a first step towards reducing irq disabled periods, move irq handling into
___slab_alloc(). Callers will instead prevent the s->cpu_slab percpu pointer
from becoming invalid via get_cpu_ptr(), thus preempt_disable(). This does not
protect against modification by an irq handler, which is still done by disabled
irq for most of ___slab_alloc(). As a small immediate benefit,
slab_out_of_memory() from ___slab_alloc() is now called with irqs enabled.

kmem_cache_alloc_bulk() disables irqs for its fastpath and then re-enables them
before calling ___slab_alloc(), which then disables them at its discretion. The
whole kmem_cache_alloc_bulk() operation also disables preemption.

When  ___slab_alloc() calls new_slab() to allocate a new page, re-enable
preemption, because new_slab() will re-enable interrupts in contexts that allow
blocking (this will be improved by later patches).

The patch itself will thus increase overhead a bit due to disabled preemption
(on configs where it matters) and increased disabling/enabling irqs in
kmem_cache_alloc_bulk(), but that will be gradually improved in the following
patches.

Note in __slab_alloc() we need to change the #ifdef CONFIG_PREEMPT guard to
CONFIG_PREEMPT_COUNT to make sure preempt disable/enable is properly paired in
all configurations. On configs without involuntary preemption and debugging
the re-read of kmem_cache_cpu pointer is still compiled out as it was before.

[ Mike Galbraith <efault@gmx.de>: Fix kmem_cache_alloc_bulk() error path ]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2021-09-04 01:12:21 +02:00
..
kasan kasan: add memzero init for unaligned size at DEBUG 2021-07-15 10:13:49 -07:00
kfence kfence: skip all GFP_ZONEMASK allocations 2021-07-23 17:43:28 -07:00
backing-dev.c writeback, cgroup: remove wb from offline list before releasing refcnt 2021-07-23 17:43:28 -07:00
balloon_compaction.c mm: fix typos in comments 2021-05-07 00:26:35 -07:00
bootmem_info.c mm: memory_hotplug: factor out bootmem core functions to bootmem_info.c 2021-06-30 20:47:25 -07:00
cleancache.c
cma_debug.c mm/cma: change cma mutex to irq safe spinlock 2021-05-05 11:27:21 -07:00
cma_sysfs.c mm: cma: support sysfs 2021-05-05 11:27:24 -07:00
cma.c mm: use proper type for cma_[alloc|release] 2021-05-05 11:27:24 -07:00
cma.h mm: cma: support sysfs 2021-05-05 11:27:24 -07:00
compaction.c Merge branch 'akpm' (patches from Andrew) 2021-07-02 12:08:10 -07:00
debug_page_ref.c
debug_vm_pgtable.c mm/swapops: rework swap entry manipulation code 2021-07-01 11:06:03 -07:00
debug.c mm/debug: factor PagePoisoned out of __dump_page 2021-06-29 10:53:53 -07:00
dmapool.c mm/dmapool: use DEVICE_ATTR_RO macro 2021-06-29 10:53:52 -07:00
early_ioremap.c mm/early_ioremap.c: use __func__ instead of function name 2021-02-26 09:41:02 -08:00
fadvise.c
failslab.c
filemap.c Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:30:04 -07:00
frontswap.c mm/mempool: minor coding style tweaks 2021-05-05 11:27:27 -07:00
gup_test.c selftests/vm: gup_test: test faulting in kernel, and verify pinnable pages 2021-05-05 11:27:26 -07:00
gup_test.h selftests/vm: gup_test: fix test flag 2021-05-05 11:27:26 -07:00
gup.c mm/madvise: report SIGBUS as -EFAULT for MADV_POPULATE_(READ|WRITE) 2021-08-13 14:09:31 -10:00
highmem.c mm: fix typos in comments 2021-05-07 00:26:35 -07:00
hmm.c mm: device exclusive memory access 2021-07-01 11:06:03 -07:00
huge_memory.c mm/rmap: fix comments left over from recent changes 2021-07-11 15:05:15 -07:00
hugetlb_cgroup.c hugetlb: make free_huge_page irq safe 2021-05-05 11:27:22 -07:00
hugetlb_vmemmap.c mm: hugetlb: introduce CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON 2021-06-30 20:47:26 -07:00
hugetlb_vmemmap.h mm: hugetlb: introduce nr_free_vmemmap_pages in the struct hstate 2021-06-30 20:47:25 -07:00
hugetlb.c hugetlb: don't pass page cache pages to restore_reserve_on_error 2021-08-20 11:31:42 -07:00
hwpoison-inject.c
init-mm.c mm: add setup_initial_init_mm() helper 2021-07-08 11:48:21 -07:00
internal.h mmap: make mlock_future_check() global 2021-07-08 11:48:20 -07:00
interval_tree.c mm/interval_tree: add comments to improve code readability 2021-04-30 11:20:38 -07:00
io-mapping.c mm: add a io_mapping_map_user helper 2021-04-30 11:20:39 -07:00
ioremap.c mm/ioremap: fix iomap_max_page_shift 2021-05-14 19:41:32 -07:00
Kconfig mm: introduce memfd_secret system call to create "secret" memory areas 2021-07-08 11:48:21 -07:00
Kconfig.debug mm, page_poison: remove CONFIG_PAGE_POISONING_ZERO 2020-12-15 12:13:46 -08:00
khugepaged.c mm, thp: relax the VM_DENYWRITE constraint on file-backed THPs 2021-06-30 20:47:29 -07:00
kmemleak.c kasan, kmemleak: reset tags when scanning block 2021-08-13 14:09:31 -10:00
ksm.c mm/ksm: use vma_lookup() in find_mergeable_vma() 2021-06-29 10:53:52 -07:00
list_lru.c mm: vmscan: consolidate shrinker_maps handling code 2021-05-05 11:27:23 -07:00
maccess.c
madvise.c mm/madvise: report SIGBUS as -EFAULT for MADV_POPULATE_(READ|WRITE) 2021-08-13 14:09:31 -10:00
Makefile mm: introduce memfd_secret system call to create "secret" memory areas 2021-07-08 11:48:21 -07:00
mapping_dirty_helpers.c mm/mapping_dirty_helpers: remove double Note in kerneldoc 2021-07-01 11:06:02 -07:00
memblock.c memblock: make for_each_mem_range() traverse MEMBLOCK_HOTPLUG regions 2021-07-23 17:43:28 -07:00
memcontrol.c mm/memcg: fix incorrect flushing of lruvec data in obj_stock 2021-08-13 14:09:32 -10:00
memfd.c Reimplement RLIMIT_MEMLOCK on top of ucounts 2021-04-30 14:14:02 -05:00
memory_hotplug.c mm/memory_hotplug: fix potential permanent lru cache disable 2021-08-25 12:25:12 -07:00
memory-failure.c mm/hwpoison: retry with shake_page() for unhandlable pages 2021-08-20 11:31:42 -07:00
memory.c mm: fix the deadlock in finish_fault() 2021-07-23 17:43:28 -07:00
mempolicy.c mm/mempolicy: use unified 'nodes' for bind/interleave/prefer policies 2021-06-30 20:47:29 -07:00
mempool.c kasan: use separate (un)poison implementation for integrated init 2021-06-04 19:32:21 +01:00
memremap.c mm/memremap.c: fix improper SPDX comment style 2021-04-30 11:20:37 -07:00
memtest.c
migrate.c mm/migrate: fix NR_ISOLATED corruption on 64-bit 2021-07-30 10:14:39 -07:00
mincore.c inode: make init and permission helpers idmapped mount aware 2021-01-24 14:27:16 +01:00
mlock.c mm: introduce memfd_secret system call to create "secret" memory areas 2021-07-08 11:48:21 -07:00
mm_init.c include/linux/page-flags-layout.h: cleanups 2021-04-30 11:20:42 -07:00
mmap_lock.c mm: mmap_lock: fix disabling preemption directly 2021-07-23 17:43:28 -07:00
mmap.c mmap: make mlock_future_check() global 2021-07-08 11:48:20 -07:00
mmu_gather.c mm: eliminate "expecting prototype" kernel-doc warnings 2021-04-16 16:10:36 -07:00
mmu_notifier.c mm/mmu_notifiers: ensure range_end() is paired with range_start() 2021-03-25 09:22:55 -07:00
mmzone.c mm/lru: replace pgdat lru_lock with lruvec lock 2020-12-15 14:48:04 -08:00
mprotect.c mm: device exclusive memory access 2021-07-01 11:06:03 -07:00
mremap.c mm/mremap: allow arch runtime override 2021-07-08 11:48:23 -07:00
msync.c mm/msync: exit early when the flags is an MS_ASYNC and start < vm_start 2021-04-30 11:20:37 -07:00
nommu.c mm/nommu: unexport do_munmap() 2021-06-30 20:47:30 -07:00
oom_kill.c Merge branch 'core-rcu-2021.07.04' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu 2021-07-04 12:58:33 -07:00
page_alloc.c mm/page_alloc: don't corrupt pcppage_migratetype 2021-08-20 11:31:42 -07:00
page_counter.c mm: page_counter: mitigate consequences of a page_counter underflow 2021-04-30 11:20:38 -07:00
page_ext.c mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM 2021-06-29 10:53:55 -07:00
page_idle.c mm: page_idle_get_page() does not need lru_lock 2020-12-15 14:48:03 -08:00
page_io.c swap: fix swapfile read/write offset 2021-03-02 17:25:46 -07:00
page_isolation.c mm/page_isolation: do not isolate the max order page 2020-12-15 12:13:45 -08:00
page_owner.c mm/page_owner: constify dump_page_owner 2021-06-29 10:53:53 -07:00
page_poison.c mm: page_poison: print page info when corruption is caught 2021-04-30 11:20:36 -07:00
page_reporting.c mm/page_reporting: allow driver to specify reporting order 2021-06-29 10:53:47 -07:00
page_reporting.h mm/page_reporting: export reporting order as module parameter 2021-06-29 10:53:47 -07:00
page_vma_mapped.c mm: device exclusive memory access 2021-07-01 11:06:03 -07:00
page-writeback.c for-5.14/block-2021-06-29 2021-06-30 12:12:56 -07:00
pagewalk.c mm: pagewalk: fix walk for hugepage tables 2021-06-29 10:53:49 -07:00
percpu-internal.h Merge branch 'for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu 2021-07-01 17:17:24 -07:00
percpu-km.c percpu: flush tlb in pcpu_reclaim_populated() 2021-07-04 18:30:17 +00:00
percpu-stats.c percpu: rework memcg accounting 2021-06-05 20:43:15 +00:00
percpu-vm.c percpu: flush tlb in pcpu_reclaim_populated() 2021-07-04 18:30:17 +00:00
percpu.c percpu: flush tlb in pcpu_reclaim_populated() 2021-07-04 18:30:17 +00:00
pgalloc-track.h mm: fix typos in comments 2021-05-07 00:26:35 -07:00
pgtable-generic.c mm/thp: fix __split_huge_pmd_locked() on shmem migration entry 2021-06-16 09:24:42 -07:00
process_vm_access.c mm/process_vm_access.c: remove duplicate include 2021-05-05 11:27:27 -07:00
ptdump.c mm: ptdump: fix build failure 2021-04-16 16:10:37 -07:00
readahead.c mm: Implement readahead_control pageset expansion 2021-04-23 10:14:29 +01:00
rmap.c mm/rmap: fix munlocking Anon THP with mlocked ptes 2021-07-12 11:30:56 -07:00
rodata_test.c
secretmem.c mm/secretmem: wire up ->set_page_dirty 2021-07-23 17:43:28 -07:00
shmem.c Revert "mm/shmem: fix shmem_swapin() race with swapoff" 2021-08-20 11:31:41 -07:00
shuffle.c mm: eliminate "expecting prototype" kernel-doc warnings 2021-04-16 16:10:36 -07:00
shuffle.h mm/shuffle: fix section mismatch warning 2021-05-22 15:09:07 -10:00
slab_common.c Merge branch 'core-rcu-2021.07.04' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu 2021-07-04 12:58:33 -07:00
slab.c mm: fix typos in comments 2021-05-07 00:26:35 -07:00
slab.h mm/memcg: fix NULL pointer dereference in memcg_slab_free_hook() 2021-07-30 10:14:39 -07:00
slob.c mm: Don't build mm_dump_obj() on CONFIG_PRINTK=n kernels 2021-03-08 14:18:46 -08:00
slub.c mm, slub: move disabling/enabling irqs to ___slab_alloc() 2021-09-04 01:12:21 +02:00
sparse-vmemmap.c mm: sparsemem: split the huge PMD mapping of vmemmap pages 2021-06-30 20:47:26 -07:00
sparse.c mm: memory_hotplug: factor out bootmem core functions to bootmem_info.c 2021-06-30 20:47:25 -07:00
swap_cgroup.c
swap_slots.c mm/swap_slots.c: delete meaningless forward declarations 2021-06-29 10:53:49 -07:00
swap_state.c Revert "mm: swap: check if swap backing device is congested or not" 2021-08-20 11:31:42 -07:00
swap.c mm: fix typos and grammar error in comments 2021-07-01 11:06:02 -07:00
swapfile.c mm: fix spelling mistakes 2021-07-01 11:06:02 -07:00
truncate.c mm/thp: unmap_mapping_page() to fix THP truncate_cleanup_page() 2021-06-16 09:24:42 -07:00
usercopy.c
userfaultfd.c userfaultfd/shmem: modify shmem_mfill_atomic_pte to use install_pte() 2021-06-30 20:47:27 -07:00
util.c mm: Make copy_huge_page() always available 2021-07-12 11:30:56 -07:00
vmacache.c
vmalloc.c mm/vmalloc: include header for prototype of set_iounmap_nonlazy 2021-07-01 11:06:02 -07:00
vmpressure.c
vmscan.c mm: vmscan: fix missing psi annotation for node_reclaim() 2021-08-20 11:31:42 -07:00
vmstat.c mm/vmstat: inline NUMA event counter updates 2021-06-29 10:53:54 -07:00
workingset.c mm: workingset: define macro WORKINGSET_SHIFT 2021-06-30 20:47:28 -07:00
z3fold.c mm/z3fold: add kerneldoc fields for z3fold_pool 2021-07-01 11:06:03 -07:00
zbud.c mm/zbud: add kerneldoc fields for zbud_pool 2021-07-01 11:06:03 -07:00
zpool.c mm: fix typos in comments 2021-05-07 00:26:35 -07:00
zsmalloc.c mm/zsmalloc.c: improve readability for async_free_zspage() 2021-07-01 11:06:02 -07:00
zswap.c mm/zswap.c: fix two bugs in zswap_writeback_entry() 2021-06-30 20:47:31 -07:00