Move the flowtable cleanup routines to nf_flow_table and expose the
nf_flow_table_cleanup() helper function.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
rateest_hash is supposed to be protected by xt_rateest_mutex,
and, as suggested by Eric, lookup and insert should be atomic,
so we should acquire the xt_rateest_mutex once for both.
So introduce a non-locking helper for internal use and keep the
locking one for external.
Reported-by: <syzbot+5cb189720978275e4c75@syzkaller.appspotmail.com>
Fixes: 5859034d7e ("[NETFILTER]: x_tables: add RATEEST target")
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft_flow_offload module removal does not require to flush existing
flowtables, it is valid to remove this module while keeping flowtables
around.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If netdevice goes down, then flowtable entries are scheduled to be
removed. Wait for garbage collector to have a chance to run so it can
delete them from the hashtable.
The flush call might sleep, so hold the nfnl mutex from
nft_flow_table_iterate() instead of rcu read side lock. The use of the
nfnl mutex is also implicitly fixing races between updates via nfnetlink
and netdevice event.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
xt_cgroup_info_v1->priv is an internal pointer only used for kernel,
we should not trust what user-space provides.
Reported-by: <syzbot+4fbcfcc0d2e6592bd641@syzkaller.appspotmail.com>
Fixes: c38c4597e4 ("netfilter: implement xt_cgroup cgroup2 path match")
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
config NF_FLOW_TABLE depends on NETFILTER_INGRESS. If users forget to
enable this toggle, flowtable registration fails with EOPNOTSUPP.
Moreover, turn 'select NF_FLOW_TABLE' in every flowtable family flavour
into dependency instead, otherwise this new dependency on
NETFILTER_INGRESS causes a warning. This also allows us to remove the
explicit dependency between family flowtables <-> NF_TABLES and
NF_CONNTRACK, given they depend on the NF_FLOW_TABLE core that already
expresses the general dependencies for this new infrastructure.
Moreover, NF_FLOW_TABLE_INET depends on NF_FLOW_TABLE_IPV4 and
NF_FLOWTABLE_IPV6, which already depends on NF_FLOW_TABLE. So we can get
rid of direct dependency with NF_FLOW_TABLE.
In general, let's avoid 'select', it just makes things more complicated.
Reported-by: John Crispin <john@phrozen.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Failures were seen in ICMPv6 fragmentation timeout tests if they were
run after the RFC2460 failure tests. Kernel was not sending out the
ICMPv6 fragment reassembly time exceeded packet after the fragmentation
reassembly timeout of 1 minute had elapsed.
This happened because the frag queue was not released if an error in
IPv6 fragmentation header was detected by RFC2460.
Fixes: 83f1999cae ("netfilter: ipv6: nf_defrag: Pass on packets to stack per RFC2460")
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
syzbot has noticed that xt_alloc_table_info can allocate a lot of memory.
This is an admin only interface but an admin in a namespace is sufficient
as well. eacd86ca3b ("net/netfilter/x_tables.c: use kvmalloc() in
xt_alloc_table_info()") has changed the opencoded kmalloc->vmalloc
fallback into kvmalloc. It has dropped __GFP_NORETRY on the way because
vmalloc has simply never fully supported __GFP_NORETRY semantic. This is
still the case because e.g. page tables backing the vmalloc area are
hardcoded GFP_KERNEL.
Revert back to __GFP_NORETRY as a poors man defence against excessively
large allocation request here. We will not rule out the OOM killer
completely but __GFP_NORETRY should at least stop the large request in
most cases.
[akpm@linux-foundation.org: coding-style fixes]
Fixes: eacd86ca3b ("net/netfilter/x_tables.c: use kvmalloc() in xt_alloc_tableLink: http://lkml.kernel.org/r/20180130140104.GE21609@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This implements ndo_poll_controller callback which is necessary to
enable netconsole.
Signed-off-by: Alexander Monakov <amonakov@ispras.ru>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Older versions of VIOS servers do not send the firmware level in the VPD
buffer for the ibmvnic driver. Thus, not only the current message is mis-
leading but the firmware version in the ethtool will be NULL. Therefore,
this patch fixes the firmware string and its warning.
Fixes: 4e6759be28 ("ibmvnic: Feature implementation of VPD for the ibmvnic driver")
Signed-off-by: Desnes A. Nunes do Rosario <desnesn@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pointer rq is being initialized but this value is never read, it
is being updated inside a for-loop. Remove the initialization and
move it into the scope of the for-loop.
Cleans up clang warning:
drivers/net/vmxnet3/vmxnet3_drv.c:2763:27: warning: Value stored
to 'rq' during its initialization is never read
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Shrikrishna Khare <skhare@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pointer phydev is initialized and this value is never read, phydev
is immediately updated to a new value, hence this initialization
is redundant and can be removed
Cleans up clang warning:
drivers/net/usb/lan78xx.c:2009:21: warning: Value stored to 'phydev'
during its initialization is never read
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pointer rxdesc is assigned a value that is never read, it is overwritten
by a new assignment inside a while loop hence the initial assignment
is redundant and can be removed.
Cleans up clang warning:
drivers/net/ethernet/jme.c:1074:17: warning: Value stored to 'rxdesc'
during its initialization is never read
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for your net tree,
they are:
1) Fix OOM that syskaller triggers with ipt_replace.size = -1 and
IPT_SO_SET_REPLACE socket option, from Dmitry Vyukov.
2) Check for too long extension name in xt_request_find_{match|target}
that result in out-of-bound reads, from Eric Dumazet.
3) Fix memory exhaustion bug in ipset hash:*net* types when adding ranges
that look like x.x.x.x-255.255.255.255, from Jozsef Kadlecsik.
4) Fix pointer leaks to userspace in x_tables, from Dmitry Vyukov.
5) Insufficient sanity checks in clusterip_tg_check(), also from Dmitry.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
RTM_NEWLINK supports the IFLA_IF_NETNSID property since
5bb8ed0754 so we should not error out
when it is passed.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, rocker user may experience following null pointer
derefence bug:
[ 3.062141] BUG: unable to handle kernel NULL pointer dereference at 00000000000000d0
[ 3.065163] IP: rocker_router_fib_event_work+0x36/0x110 [rocker]
The problem is uninitialized rocker->wops pointer that is initialized
only with the first initialized port. So move the port initialization
before registering the fib events.
Fixes: 936bd48656 ("rocker: use FIB notifications instead of switchdev calls")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With gcc-4.1.2:
net/ipv4/inet_hashtables.c: In function ‘inet_unhash’:
net/ipv4/inet_hashtables.c:628: warning: ‘ilb’ may be used uninitialized in this function
While this is a false positive, it can easily be avoided by using the
pointer itself as the canary variable.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
With gcc-4.1.2.:
net/bridge/br_fdb.c: In function ‘br_fdb_sync_static’:
net/bridge/br_fdb.c:996: warning: ‘err’ may be used uninitialized in this function
Indeed, if the list is empty, err will be uninitialized, and will be
propagated up as the function return value.
Fix this by preinitializing err to zero.
Fixes: eb7935830d ("net: bridge: use rhashtable for fdbs")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPv4 and IPv6 packets may arrive with lower-layer padding that is not
included in the L3 length. For example, a short IPv4 packet may have
up to 6 bytes of padding following the IP payload when received on an
Ethernet device with a minimum packet length of 64 bytes.
Higher-layer processing functions in netfilter (e.g. nf_ip_checksum(),
and help() in nf_conntrack_ftp) assume skb->len reflects the length of
the L3 header and payload, rather than referring back to
ip_hdr->tot_len or ipv6_hdr->payload_len, and get confused by
lower-layer padding.
In the normal IPv4 receive path, ip_rcv() trims the packet to
ip_hdr->tot_len before invoking netfilter hooks. In the IPv6 receive
path, ip6_rcv() does the same using ipv6_hdr->payload_len. Similarly
in the br_netfilter receive path, br_validate_ipv4() and
br_validate_ipv6() trim the packet to the L3 length before invoking
netfilter hooks.
Currently in the OVS conntrack receive path, ovs_ct_execute() pulls
the skb to the L3 header but does not trim it to the L3 length before
calling nf_conntrack_in(NF_INET_PRE_ROUTING). When
nf_conntrack_proto_tcp encounters a packet with lower-layer padding,
nf_ip_checksum() fails causing a "nf_ct_tcp: bad TCP checksum" log
message. While extra zero bytes don't affect the checksum, the length
in the IP pseudoheader does. That length is based on skb->len, and
without trimming, it doesn't match the length the sender used when
computing the checksum.
In ovs_ct_execute(), trim the skb to the L3 length before higher-layer
processing.
Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit fixes the pacing_gain to remain at BBR_UNIT (1.0) when
using lt_bw and returning from the PROBE_RTT state to PROBE_BW.
Previously, when using lt_bw, upon exiting PROBE_RTT and entering
PROBE_BW the bbr_reset_probe_bw_mode() code could sometimes randomly
end up with a cycle_idx of 0 and hence have bbr_advance_cycle_phase()
set a pacing gain above 1.0. In such cases this would result in a
pacing rate that is 1.25x higher than intended, potentially resulting
in a high loss rate for a little while until we stop using the lt_bw a
bit later.
This commit is a stable candidate for kernels back as far as 4.9.
Fixes: 0f8782ea14 ("tcp_bbr: add BBR congestion control")
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Reported-by: Beyers Cronje <bcronje@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Variable head is initialized to a value that is never read and is
being updated to a new value a few lines later, hence this
initialization is redundant and can be safely removed as well
as the now unused pointer txq.
Cleans up clang warning:
drivers/net/ethernet/emulex/benet/be_main.c:996:6: warning: Value
stored to 'head' during its initialization is never read
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Axtens says:
====================
bnx2x: disable GSO on too-large packets
We observed a case where a packet received on an ibmveth device had a
GSO size of around 10kB. This was forwarded by Open vSwitch to a bnx2x
device, where it caused a firmware assert. This is described in detail
at [0].
Ultimately we want a fix in the core, but that is very tricky to
backport. So for now, just stop the bnx2x driver from crashing.
When net-next re-opens I will send the fix to the core and a revert
for this.
v4 changes:
- fix compilation error with EXPORTs (patch 1)
- only do slow test if gso_size is greater than 9000 bytes (patch 2)
Thanks,
Daniel
[0]: https://patchwork.ozlabs.org/patch/859410/
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
If a bnx2x card is passed a GSO packet with a gso_size larger than
~9700 bytes, it will cause a firmware error that will bring the card
down:
bnx2x: [bnx2x_attn_int_deasserted3:4323(enP24p1s0f0)]MC assert!
bnx2x: [bnx2x_mc_assert:720(enP24p1s0f0)]XSTORM_ASSERT_LIST_INDEX 0x2
bnx2x: [bnx2x_mc_assert:736(enP24p1s0f0)]XSTORM_ASSERT_INDEX 0x0 = 0x00000000 0x25e43e47 0x00463e01 0x00010052
bnx2x: [bnx2x_mc_assert:750(enP24p1s0f0)]Chip Revision: everest3, FW Version: 7_13_1
... (dump of values continues) ...
Detect when the mac length of a GSO packet is greater than the maximum
packet size (9700 bytes) and disable GSO.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If you take a GSO skb, and split it into packets, will the MAC
length (L2 + L3 + L4 headers + payload) of those packets be small
enough to fit within a given length?
Move skb_gso_mac_seglen() to skbuff.h with other related functions
like skb_gso_network_seglen() so we can use it, and then create
skb_gso_validate_mac_len to do the full calculation.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
documentation, errseq documentation, kernel-doc support for nested
structure definitions, the removal of lots of crufty kernel-doc support for
unused formats, SPDX tag documentation, the beginnings of a manual for
subsystem maintainers, and lots of fixes and updates.
As usual, some of the changesets reach outside of Documentation/ to effect
kerneldoc comment fixes. It also adds the new LICENSES directory, of which
Thomas promises I do not need to be the maintainer.
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Merge tag 'docs-4.16' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"Documentation updates for 4.16.
New stuff includes refcount_t documentation, errseq documentation,
kernel-doc support for nested structure definitions, the removal of
lots of crufty kernel-doc support for unused formats, SPDX tag
documentation, the beginnings of a manual for subsystem maintainers,
and lots of fixes and updates.
As usual, some of the changesets reach outside of Documentation/ to
effect kerneldoc comment fixes. It also adds the new LICENSES
directory, of which Thomas promises I do not need to be the
maintainer"
* tag 'docs-4.16' of git://git.lwn.net/linux: (65 commits)
linux-next: docs-rst: Fix typos in kfigure.py
linux-next: DOC: HWPOISON: Fix path to debugfs in hwpoison.txt
Documentation: Fix misconversion of #if
docs: add index entry for networking/msg_zerocopy
Documentation: security/credentials.rst: explain need to sort group_list
LICENSES: Add MPL-1.1 license
LICENSES: Add the GPL 1.0 license
LICENSES: Add Linux syscall note exception
LICENSES: Add the MIT license
LICENSES: Add the BSD-3-clause "Clear" license
LICENSES: Add the BSD 3-clause "New" or "Revised" License
LICENSES: Add the BSD 2-clause "Simplified" license
LICENSES: Add the LGPL-2.1 license
LICENSES: Add the LGPL 2.0 license
LICENSES: Add the GPL 2.0 license
Documentation: Add license-rules.rst to describe how to properly identify file licenses
scripts: kernel_doc: better handle show warnings logic
fs/*/Kconfig: drop links to 404-compliant http://acl.bestbits.at
doc: md: Fix a file name to md-fault.c in fault-injection.txt
errseq: Add to documentation tree
...
Pull vmci iov_iter updates from Al Viro:
"Get rid of "is it an iovec or an entire array?" flags in vmxi - just
use iov_iter. Simplifies the living hell out of that code..."
* 'work.vmci' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vmci: the same on the send side...
vmci: simplify qp_dequeue_locked()
vmci: get rid of qp_memcpy_from_queue()
vmci: fix buf_size in case of iovec-based accesses
Pull asm/uaccess.h whack-a-mole from Al Viro:
"It's linux/uaccess.h, damnit... Oh, well - eventually they'll stop
cropping up..."
* 'work.whack-a-mole' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
asm-prototypes.h: use linux/uaccess.h, not asm/uaccess.h
riscv: use linux/uaccess.h, not asm/uaccess.h...
ppc: for put_user() pull linux/uaccess.h, not asm/uaccess.h
Pull dcache updates from Al Viro:
"Neil Brown's d_move()/d_path() race fix"
* 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
VFS: close race between getcwd() and d_move()
Merge updates from Andrew Morton:
- misc fixes
- ocfs2 updates
- most of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
mm: remove PG_highmem description
tools, vm: new option to specify kpageflags file
mm/swap.c: make functions and their kernel-doc agree
mm, memory_hotplug: fix memmap initialization
mm: correct comments regarding do_fault_around()
mm: numa: do not trap faults on shared data section pages.
hugetlb, mbind: fall back to default policy if vma is NULL
hugetlb, mempolicy: fix the mbind hugetlb migration
mm, hugetlb: further simplify hugetlb allocation API
mm, hugetlb: get rid of surplus page accounting tricks
mm, hugetlb: do not rely on overcommit limit during migration
mm, hugetlb: integrate giga hugetlb more naturally to the allocation path
mm, hugetlb: unify core page allocation accounting and initialization
mm/memcontrol.c: try harder to decrease [memory,memsw].limit_in_bytes
mm/memcontrol.c: make local symbol static
mm/hmm: fix uninitialized use of 'entry' in hmm_vma_walk_pmd()
include/linux/mmzone.h: fix explanation of lower bits in the SPARSEMEM mem_map pointer
mm/compaction.c: fix comment for try_to_compact_pages()
mm/page_ext.c: make page_ext_init a noop when CONFIG_PAGE_EXTENSION but nothing uses it
zsmalloc: use U suffix for negative literals being shifted
...
Commit cbe37d0937 ("[PATCH] mm: remove PG_highmem") removed PG_highmem
to save a page flag. So the description of PG_highmem is no longer
needed.
Link: http://lkml.kernel.org/r/1517391212-2950-1-git-send-email-miles.chen@mediatek.com
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
page-types currently hardcodes /proc/kpageflags as the file to parse.
This works when using the tool to examine the state of pageflags on the
same system, but does not allow storing a snapshot of pageflags at a
given time to debug issues nor on a different system.
This allows the user to specify a saved version of kpageflags with a new
page-types -F option.
[akpm@linux-foundation.org: add "filename" to fix usage() string]
[rientjes@google.com: fix layout]
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1801301840050.140969@chino.kir.corp.google.com
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1801301458180.153857@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix some basic kernel-doc notation in mm/swap.c:
- for function lru_cache_add_anon(), make its kernel-doc function name
match its function name and change colon to hyphen following the
function name
- for function pagevec_lookup_entries(), change the function parameter
name from nr_pages to nr_entries since that is more descriptive of
what the parameter actually is and then it matches the kernel-doc
comments also
Fix function kernel-doc to match the change in commit 67fd707f46:
- drop the kernel-doc notation for @nr_pages from
pagevec_lookup_range() and correct the function description for that
change
Link: http://lkml.kernel.org/r/3b42ee3e-04a9-a6ca-6be4-f00752a114fe@infradead.org
Fixes: 67fd707f46 ("mm: remove nr_pages argument from pagevec_lookup_{,range}_tag()")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bharata has noticed that onlining a newly added memory doesn't increase
the total memory, pointing to commit f7f99100d8 ("mm: stop zeroing
memory during allocation in vmemmap") as a culprit. This commit has
changed the way how the memory for memmaps is initialized and moves it
from the allocation time to the initialization time. This works
properly for the early memmap init path.
It doesn't work for the memory hotplug though because we need to mark
page as reserved when the sparsemem section is created and later
initialize it completely during onlining. memmap_init_zone is called in
the early stage of onlining. With the current code it calls
__init_single_page and as such it clears up the whole stage and
therefore online_pages_range skips those pages.
Fix this by skipping mm_zero_struct_page in __init_single_page for
memory hotplug path. This is quite uggly but unifying both early init
and memory hotplug init paths is a large project. Make sure we plug the
regression at least.
Link: http://lkml.kernel.org/r/20180130101141.GW21609@dhcp22.suse.cz
Fixes: f7f99100d8 ("mm: stop zeroing memory during allocation in vmemmap")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Tested-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Bob Picco <bob.picco@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are multiple comments surrounding do_fault_around that memtion
fault_around_pages() and fault_around_mask(), two routines that do not
exist. These comments should be reworded to reference
fault_around_bytes, the value which is used to determine how much
do_fault_around() will attempt to read when processing a fault.
These comments should have been updated when fault_around_pages() and
fault_around_mask() were removed in commit aecd6f4426 ("mm: close race
between do_fault_around() and fault_around_bytes_set()").
Fixes: aecd6f4426 ("mm: close race between do_fault_around() and fault_around_bytes_set()")
Link: http://lkml.kernel.org/r/302D0B14-C7E9-44C6-8BED-033F9ACBD030@oracle.com
Signed-off-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: Larry Bassel <larry.bassel@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Workloads consisting of a large number of processes running the same
program with a very large shared data segment may experience performance
problems when numa balancing attempts to migrate the shared cow pages.
This manifests itself with many processes or tasks in
TASK_UNINTERRUPTIBLE state waiting for the shared pages to be migrated.
The program listed below simulates the conditions with these results
when run with 288 processes on a 144 core/8 socket machine.
Average throughput Average throughput Average throughput
with numa_balancing=0 with numa_balancing=1 with numa_balancing=1
without the patch with the patch
--------------------- --------------------- ---------------------
2118782 2021534 2107979
Complex production environments show less variability and fewer poorly
performing outliers accompanied with a smaller number of processes
waiting on NUMA page migration with this patch applied. In some cases,
%iowait drops from 16%-26% to 0.
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
*/
#include <sys/time.h>
#include <stdio.h>
#include <wait.h>
#include <sys/mman.h>
int a[1000000] = {13};
int main(int argc, const char **argv)
{
int n = 0;
int i;
pid_t pid;
int stat;
int *count_array;
int cpu_count = 288;
long total = 0;
struct timeval t1, t2 = {(argc > 1 ? atoi(argv[1]) : 10), 0};
if (argc > 2)
cpu_count = atoi(argv[2]);
count_array = mmap(NULL, cpu_count * sizeof(int),
(PROT_READ|PROT_WRITE),
(MAP_SHARED|MAP_ANONYMOUS), 0, 0);
if (count_array == MAP_FAILED) {
perror("mmap:");
return 0;
}
for (i = 0; i < cpu_count; ++i) {
pid = fork();
if (pid <= 0)
break;
if ((i & 0xf) == 0)
usleep(2);
}
if (pid != 0) {
if (i == 0) {
perror("fork:");
return 0;
}
for (;;) {
pid = wait(&stat);
if (pid < 0)
break;
}
for (i = 0; i < cpu_count; ++i)
total += count_array[i];
printf("Total %ld\n", total);
munmap(count_array, cpu_count * sizeof(int));
return 0;
}
gettimeofday(&t1, 0);
timeradd(&t1, &t2, &t1);
while (timercmp(&t2, &t1, <)) {
int b = 0;
int j;
for (j = 0; j < 1000000; j++)
b += a[j];
gettimeofday(&t2, 0);
n++;
}
count_array[i] = n;
return 0;
}
This patch changes change_pte_range() to skip shared copy-on-write pages
when called from change_prot_numa().
NOTE: change_prot_numa() is nominally called from task_numa_work() and
queue_pages_test_walk(). task_numa_work() is the auto NUMA balancing
path, and queue_pages_test_walk() is part of explicit NUMA policy
management. However, queue_pages_test_walk() only calls
change_prot_numa() when MPOL_MF_LAZY is specified and currently that is
not allowed, so change_prot_numa() is only called from auto NUMA
balancing.
In the case of explicit NUMA policy management, shared pages are not
migrated unless MPOL_MF_MOVE_ALL is specified, and MPOL_MF_MOVE_ALL
depends on CAP_SYS_NICE. Currently, there is no way to pass information
about MPOL_MF_MOVE_ALL to change_pte_range. This will have to be fixed
if MPOL_MF_LAZY is enabled and MPOL_MF_MOVE_ALL is to be honored in lazy
migration mode.
task_numa_work() skips the read-only VMAs of programs and shared
libraries.
Link: http://lkml.kernel.org/r/1516751617-7369-1-git-send-email-henry.willard@oracle.com
Signed-off-by: Henry Willard <henry.willard@oracle.com>
Reviewed-by: Håkon Bugge <haakon.bugge@oracle.com>
Reviewed-by: Steve Sistare <steven.sistare@oracle.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Carpenter has noticed that mbind migration callback (new_page) can
get a NULL vma pointer and choke on it inside alloc_huge_page_vma which
relies on the VMA to get the hstate. We used to BUG_ON this case but
the BUG_+ON has been removed recently by "hugetlb, mempolicy: fix the
mbind hugetlb migration".
The proper way to handle this is to get the hstate from the migrated
page and rely on huge_node (resp. get_vma_policy) do the right thing
with null VMA. We are currently falling back to the default mempolicy
in that case which is in line what THP path is doing here.
Link: http://lkml.kernel.org/r/20180110104712.GR1732@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
do_mbind migration code relies on alloc_huge_page_noerr for hugetlb
pages. alloc_huge_page_noerr uses alloc_huge_page which is a highlevel
allocation function which has to take care of reserves, overcommit or
hugetlb cgroup accounting. None of that is really required for the page
migration because the new page is only temporal and either will replace
the original page or it will be dropped. This is essentially as for
other migration call paths and there shouldn't be any reason to handle
mbind in a special way.
The current implementation is even suboptimal because the migration
might fail just because the hugetlb cgroup limit is reached, or the
overcommit is saturated.
Fix this by making mbind like other hugetlb migration paths. Add a new
migration helper alloc_huge_page_vma as a wrapper around
alloc_huge_page_nodemask with additional mempolicy handling.
alloc_huge_page_noerr has no more users and it can go.
Link: http://lkml.kernel.org/r/20180103093213.26329-7-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andrea Reale <ar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugetlb allocator has several layer of allocation functions depending
and the purpose of the allocation. There are two allocators depending
on whether the page can be allocated from the page allocator or we need
a contiguous allocator. This is currently opencoded in
alloc_fresh_huge_page which is the only path that might allocate giga
pages which require the later allocator. Create alloc_fresh_huge_page
which hides this implementation detail and use it in all callers which
hardcoded the buddy allocator path (__hugetlb_alloc_buddy_huge_page).
This shouldn't introduce any funtional change because both migration and
surplus allocators exlude giga pages explicitly.
While we are at it let's do some renaming. The current scheme is not
consistent and overly painfull to read and understand. Get rid of
prefix underscores from most functions. There is no real reason to make
names longer.
* alloc_fresh_huge_page is the new layer to abstract underlying
allocator
* __hugetlb_alloc_buddy_huge_page becomes shorter and neater
alloc_buddy_huge_page.
* Former alloc_fresh_huge_page becomes alloc_pool_huge_page because we put
the new page directly to the pool
* alloc_surplus_huge_page can drop the opencoded prep_new_huge_page code
as it uses alloc_fresh_huge_page now
* others lose their excessive prefix underscores to make names shorter
[dan.carpenter@oracle.com: fix double unlock bug in alloc_surplus_huge_page()]
Link: http://lkml.kernel.org/r/20180109200559.g3iz5kvbdrz7yydp@mwanda
Link: http://lkml.kernel.org/r/20180103093213.26329-6-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andrea Reale <ar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
alloc_surplus_huge_page increases the pool size and the number of
surplus pages opportunistically to prevent from races with the pool size
change. See commit d1c3fb1f8f ("hugetlb: introduce
nr_overcommit_hugepages sysctl") for more details.
The resulting code is unnecessarily hairy, cause code duplication and
doesn't allow to share the allocation paths. Moreover pool size changes
tend to be very seldom so optimizing for them is not really reasonable.
Simplify the code and allow to allocate a fresh surplus page as long as
we are under the overcommit limit and then recheck the condition after
the allocation and drop the new page if the situation has changed. This
should provide a reasonable guarantee that an abrupt allocation requests
will not go way off the limit.
If we consider races with the pool shrinking and enlarging then we
should be reasonably safe as well. In the first case we are off by one
in the worst case and the second case should work OK because the page is
not yet visible. We can waste CPU cycles for the allocation but that
should be acceptable for a relatively rare condition.
Link: http://lkml.kernel.org/r/20180103093213.26329-5-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andrea Reale <ar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hugepage migration relies on __alloc_buddy_huge_page to get a new page.
This has 2 main disadvantages.
1) it doesn't allow to migrate any huge page if the pool is used
completely which is not an exceptional case as the pool is static and
unused memory is just wasted.
2) it leads to a weird semantic when migration between two numa nodes
might increase the pool size of the destination NUMA node while the
page is in use. The issue is caused by per NUMA node surplus pages
tracking (see free_huge_page).
Address both issues by changing the way how we allocate and account
pages allocated for migration. Those should temporal by definition. So
we mark them that way (we will abuse page flags in the 3rd page) and
update free_huge_page to free such pages to the page allocator. Page
migration path then just transfers the temporal status from the new page
to the old one which will be freed on the last reference. The global
surplus count will never change during this path but we still have to be
careful when migrating a per-node suprlus page. This is now handled in
move_hugetlb_state which is called from the migration path and it copies
the hugetlb specific page state and fixes up the accounting when needed
Rename __alloc_buddy_huge_page to __alloc_surplus_huge_page to better
reflect its purpose. The new allocation routine for the migration path
is __alloc_migrate_huge_page.
The user visible effect of this patch is that migrated pages are really
temporal and they travel between NUMA nodes as per the migration
request:
Before migration
/sys/devices/system/node/node0/hugepages/hugepages-2048kB/free_hugepages:0
/sys/devices/system/node/node0/hugepages/hugepages-2048kB/nr_hugepages:1
/sys/devices/system/node/node0/hugepages/hugepages-2048kB/surplus_hugepages:0
/sys/devices/system/node/node1/hugepages/hugepages-2048kB/free_hugepages:0
/sys/devices/system/node/node1/hugepages/hugepages-2048kB/nr_hugepages:0
/sys/devices/system/node/node1/hugepages/hugepages-2048kB/surplus_hugepages:0
After
/sys/devices/system/node/node0/hugepages/hugepages-2048kB/free_hugepages:0
/sys/devices/system/node/node0/hugepages/hugepages-2048kB/nr_hugepages:0
/sys/devices/system/node/node0/hugepages/hugepages-2048kB/surplus_hugepages:0
/sys/devices/system/node/node1/hugepages/hugepages-2048kB/free_hugepages:0
/sys/devices/system/node/node1/hugepages/hugepages-2048kB/nr_hugepages:1
/sys/devices/system/node/node1/hugepages/hugepages-2048kB/surplus_hugepages:0
with the previous implementation, both nodes would have nr_hugepages:1
until the page is freed.
Link: http://lkml.kernel.org/r/20180103093213.26329-4-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andrea Reale <ar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Gigantic hugetlb pages were ingrown to the hugetlb code as an alien
specie with a lot of special casing. The allocation path is not an
exception. Unnecessarily so to be honest. It is true that the
underlying allocator is different but that is an implementation detail.
This patch unifies the hugetlb allocation path that a prepares fresh
pool pages. alloc_fresh_gigantic_page basically copies
alloc_fresh_huge_page logic so we can move everything there. This will
simplify set_max_huge_pages which doesn't have to care about what kind
of huge page we allocate.
Link: http://lkml.kernel.org/r/20180103093213.26329-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andrea Reale <ar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm, hugetlb: allocation API and migration improvements"
Motivation:
this is a follow up for [3] for the allocation API and [4] for the
hugetlb migration. It wasn't really easy to split those into two
separate patch series as they share some code.
My primary motivation to touch this code is to make the gigantic pages
migration working. The giga pages allocation code is just too fragile
and hacked into the hugetlb code now. This series tries to move giga
pages closer to the first class citizen. We are not there yet but
having 5 patches is quite a lot already and it will already make the
code much easier to follow. I will come with other changes on top after
this sees some review.
The first two patches should be trivial to review. The third patch
changes the way how we migrate huge pages. Newly allocated pages are a
subject of the overcommit check and they participate surplus accounting
which is quite unfortunate as the changelog explains. This patch
doesn't change anything wrt. giga pages.
Patch #4 removes the surplus accounting hack from
__alloc_surplus_huge_page. I hope I didn't miss anything there and a
deeper review is really due there.
Patch #5 finally unifies allocation paths and giga pages shouldn't be
any special anymore. There is also some renaming going on as well.
This patch (of 6):
hugetlb allocator has two entry points to the page allocator
- alloc_fresh_huge_page_node
- __hugetlb_alloc_buddy_huge_page
The two differ very subtly in two aspects. The first one doesn't care
about HTLB_BUDDY_* stats and it doesn't initialize the huge page.
prep_new_huge_page is not used because it not only initializes hugetlb
specific stuff but because it also put_page and releases the page to the
hugetlb pool which is not what is required in some contexts. This makes
things more complicated than necessary.
Simplify things by a) removing the page allocator entry point duplicity
and only keep __hugetlb_alloc_buddy_huge_page and b) make
prep_new_huge_page more reusable by removing the put_page which moves
the page to the allocator pool. All current callers are updated to call
put_page explicitly. Later patches will add new callers which won't
need it.
This patch shouldn't introduce any functional change.
Link: http://lkml.kernel.org/r/20180103093213.26329-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andrea Reale <ar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mem_cgroup_resize_[memsw]_limit() tries to free only 32
(SWAP_CLUSTER_MAX) pages on each iteration. This makes it practically
impossible to decrease limit of memory cgroup. Tasks could easily
allocate back 32 pages, so we can't reduce memory usage, and once
retry_count reaches zero we return -EBUSY.
Easy to reproduce the problem by running the following commands:
mkdir /sys/fs/cgroup/memory/test
echo $$ >> /sys/fs/cgroup/memory/test/tasks
cat big_file > /dev/null &
sleep 1 && echo $((100*1024*1024)) > /sys/fs/cgroup/memory/test/memory.limit_in_bytes
-bash: echo: write error: Device or resource busy
Instead of relying on retry_count, keep retrying the reclaim until the
desired limit is reached or fail if the reclaim doesn't make any
progress or a signal is pending.
Link: http://lkml.kernel.org/r/20180119132544.19569-1-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the following sparse warning:
mm/memcontrol.c:1097:14: warning: symbol 'memcg1_stats' was not declared. Should it be static?
Link: http://lkml.kernel.org/r/20180118193327.14200-1-chrisadr@gentoo.org
Signed-off-by: Christopher Díaz Riveros <chrisadr@gentoo.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The variable 'entry' is used before being initialized in
hmm_vma_walk_pmd().
No bad effect (beside performance hit) so !non_swap_entry(0) evaluate to
true which trigger a fault as if CPU was trying to access migrated
memory and migrate memory back from device memory to regular memory.
This function (hmm_vma_walk_pmd()) is called when a device driver tries
to populate its own page table. For migrated memory it should not
happen as the device driver should already have populated its page table
correctly during the migration.
Only case I can think of is multi-GPU where a second GPU triggers
migration back to regular memory. Again this would just result in a
performance hit, nothing bad would happen.
Link: http://lkml.kernel.org/r/20180122185759.26286-1-jglisse@redhat.com
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The comment is confusing. On the one hand, it refers to 32-bit
alignment (struct page alignment on 32-bit platforms), but this would
only guarantee that the 2 lowest bits must be zero. On the other hand,
it claims that at least 3 bits are available, and 3 bits are actually
used.
This is not broken, because there is a stronger alignment guarantee,
just less obvious. Let's fix the comment to make it clear how many bits
are available and why.
Although memmap arrays are allocated in various places, the resulting
pointer is encoded eventually, so I am adding a BUG_ON() here to enforce
at runtime that all expected bits are indeed available.
I have also added a BUILD_BUG_ON to check that PFN_SECTION_SHIFT is
sufficient, because this part of the calculation can be easily checked
at build time.
[ptesarik@suse.com: v2]
Link: http://lkml.kernel.org/r/20180125100516.589ea6af@ezekiel.suse.cz
Link: http://lkml.kernel.org/r/20180119080908.3a662e6f@ezekiel.suse.cz
Signed-off-by: Petr Tesarik <ptesarik@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kemi Wang <kemi.wang@intel.com>
Cc: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
"mode" argument is not used by try_to_compact_pages() and sub functions
anymore, it has been replaced by "prio". Fix the comment to explain the
use of "prio" argument.
Link: http://lkml.kernel.org/r/1515801336-20611-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
static struct page_ext_operations *page_ext_ops[] always contains debug_guardpage_ops,
static struct page_ext_operations *page_ext_ops[] = {
&debug_guardpage_ops,
#ifdef CONFIG_PAGE_OWNER
&page_owner_ops,
#endif
...
}
but for it to work, CONFIG_DEBUG_PAGEALLOC must be enabled first. If
someone has CONFIG_PAGE_EXTENSION, but has none of its users, eg:
(CONFIG_PAGE_OWNER, CONFIG_DEBUG_PAGEALLOC, CONFIG_IDLE_PAGE_TRACKING),
we can shrink page_ext_init() to a simple retq.
$ size vmlinux (before patch)
text data bss dec hex filename
14356698 5681582 1687748 21726028 14b834c vmlinux
$ size vmlinux (after patch)
text data bss dec hex filename
14356008 5681538 1687748 21725294 14b806e vmlinux
On the other hand, it might does not even make sense, since if someone
enables CONFIG_PAGE_EXTENSION, I would expect him to enable also at
least one of its users.
Link: http://lkml.kernel.org/r/20180105130235.GA21241@techadventures.net
Signed-off-by: Oscar Salvador <osalvador@techadventures.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jaewon Kim <jaewon31.kim@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
