David Rientjes 7b98c2e402 oom: give current access to memory reserves if it has been killed ... It's possible to livelock the page allocator if a thread has mm->mmap_sem and fails to make forward progress because the oom killer selects another thread sharing the same ->mm to kill that cannot exit until the semaphore is dropped. The oom killer will not kill multiple tasks at the same time; each oom killed task must exit before another task may be killed. Thus, if one thread is holding mm->mmap_sem and cannot allocate memory, all threads sharing the same ->mm are blocked from exiting as well. In the oom kill case, that means the thread holding mm->mmap_sem will never free additional memory since it cannot get access to memory reserves and the thread that depends on it with access to memory reserves cannot exit because it cannot acquire the semaphore. Thus, the page allocators livelocks. When the oom killer is called and current happens to have a pending SIGKILL, this patch automatically gives it access to memory reserves and returns. Upon returning to the page allocator, its allocation will hopefully succeed so it can quickly exit and free its memory. If not, the page allocator will fail the allocation if it is not __GFP_NOFAIL. Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2010-08-09 20:44:56 -07:00
..
backing-dev.c	Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-08-06 09:23:07 -07:00
bootmem.c	x86,nobootmem: make alloc_bootmem_node fall back to other node when 32bit numa is used	2010-07-20 16:25:40 -07:00
bounce.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
compaction.c	mm: compaction: add a tunable that decides when memory should be compacted and when it should be reclaimed	2010-05-25 08:06:59 -07:00
debug-pagealloc.c	generic debug pagealloc	2009-04-01 08:59:13 -07:00
dmapool.c	dmapools: protect page_list walk in show_pools()	2009-06-30 18:56:00 -07:00
fadvise.c	readahead: introduce FMODE_RANDOM for POSIX_FADV_RANDOM	2010-03-06 11:26:25 -08:00
failslab.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
filemap_xip.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
filemap.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse	2010-05-30 09:16:14 -07:00
fremap.c	mm: clean up mm_counter	2010-03-06 11:26:23 -08:00
highmem.c	mm,kdb,kgdb: Add a debug reference for the kdb kmap usage	2010-08-05 09:22:24 -05:00
hugetlb.c	hugetlb: call mmu notifiers on hugepage cow	2010-08-09 20:44:54 -07:00
hwpoison-inject.c	HWPOISON: Don't do early filtering if filter is disabled	2009-12-16 12:20:01 +01:00
init-mm.c	mm: provide init_mm mm_context initializer	2010-08-09 20:44:54 -07:00
internal.h	HWPOISON: add an interface to switch off/on all the page filters	2009-12-16 12:19:59 +01:00
Kconfig	lmb: rename to memblock	2010-07-14 17:14:00 +10:00
Kconfig.debug	trivial: improve help text for mm debug config options	2009-09-21 15:14:57 +02:00
kmemcheck.c	kmemcheck: Fix build errors due to missing slab.h	2010-03-30 22:02:32 +09:00
kmemleak-test.c	percpu: clean up percpu variable definitions	2009-06-24 15:13:48 +09:00
kmemleak.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
ksm.c	mm: extend KSM refcounts to the anon_vma root	2010-08-09 20:44:55 -07:00
maccess.c	maccess,probe_kernel: Allow arch specific override probe_kernel_(read|write)	2010-01-07 11:58:36 -06:00
madvise.c	HWPOISON: Add a madvise() injector for soft page offlining	2009-12-16 12:20:00 +01:00
Makefile	lmb: rename to memblock	2010-07-14 17:14:00 +10:00
memblock.c	lmb: rename to memblock	2010-07-14 17:14:00 +10:00
memcontrol.c	memcg: fix wake up in oom wait queue	2010-06-29 15:29:30 -07:00
memory_hotplug.c	mem-hotplug: fix potential race while building zonelist for new populated zone	2010-05-25 08:07:02 -07:00
memory-failure.c	KVM: Fix a race condition for usage of is_hwpoison_address()	2010-08-01 10:47:11 +03:00
memory.c	mm: fix ia64 crash when gcore reads gate area	2010-07-30 18:56:09 -07:00
mempolicy.c	mempolicy: fix dangling reference to tmpfs superblock mpol	2010-06-29 15:29:31 -07:00
mempool.c	mm: remove broken 'kzalloc' mempool	2009-09-22 07:17:35 -07:00
migrate.c	mm: extend KSM refcounts to the anon_vma root	2010-08-09 20:44:55 -07:00
mincore.c	mincore: do nested page table walks	2010-05-25 08:06:58 -07:00
mlock.c	x86, perf, bts, mm: Delete the never used BTS-ptrace code	2010-03-26 11:33:55 +01:00
mm_init.c	mm: mminit_loglevel cannot be __meminitdata anymore	2008-08-20 15:40:30 -07:00
mmap.c	mm: always lock the root (oldest) anon_vma	2010-08-09 20:44:55 -07:00
mmu_context.c	exit: fix oops in sync_mm_rss	2010-03-24 16:31:21 -07:00
mmu_notifier.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
mmzone.c	[ARM] Double check memmap is actually valid with a memmap has unexpected holes V2	2009-05-18 11:22:24 +01:00
mprotect.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
mremap.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
msync.c	sanitize vfs_fsync calling conventions	2010-05-21 18:31:21 -04:00
nommu.c	nommu: allow private mappings of read-only devices	2010-05-26 08:19:23 -07:00
oom_kill.c	oom: give current access to memory reserves if it has been killed	2010-08-09 20:44:56 -07:00
page_alloc.c	x86,nobootmem: make alloc_bootmem_node fall back to other node when 32bit numa is used	2010-07-20 16:25:40 -07:00
page_cgroup.c	kmemleak: Annotate false positive in init_section_page_cgroup()	2010-07-19 11:54:14 +01:00
page_io.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
page_isolation.c	memory hotplug: fix page_zone() calculation in test_pages_isolated()	2008-11-06 15:41:19 -08:00
page-writeback.c	writeback: remove writeback_inodes_wbc	2010-07-06 08:54:03 +02:00
pagewalk.c	pagemap: fix pfn calculation for hugepage	2010-04-07 08:38:04 -07:00
percpu_up.c	percpu: don't implicitly include slab.h from percpu.h	2010-03-30 22:02:32 +09:00
percpu-km.c	percpu: implement kernel memory based chunk allocation	2010-05-01 08:30:50 +02:00
percpu-vm.c	percpu: move vmalloc based chunk management into percpu-vm.c	2010-05-01 08:30:50 +02:00
percpu.c	percpu: allow limited allocation before slab is online	2010-06-27 18:50:00 +02:00
prio_tree.c
quicklist.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
readahead.c	readahead.c: fix comment	2010-05-25 08:07:00 -07:00
rmap.c	mm: extend KSM refcounts to the anon_vma root	2010-08-09 20:44:55 -07:00
shmem.c	fix truncate inode time modification breakage	2010-06-04 17:16:30 -04:00
slab.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6	2010-08-06 11:44:08 -07:00
slob.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6	2010-08-06 11:44:08 -07:00
slub.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6	2010-08-06 11:44:08 -07:00
sparse-vmemmap.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
sparse.c	sparsemem: on no vmemmap path put mem_map on node high too	2010-05-25 08:06:56 -07:00
swap_state.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
swap.c	mm: export lru_cache_add_*() to modules	2010-05-25 15:06:06 +02:00
swapfile.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6	2010-05-21 15:26:46 -07:00
thrash.c	mm: pass mm to grab_swap_token	2009-06-23 12:50:05 -07:00
truncate.c	fs: introduce new truncate sequence	2010-05-27 22:15:33 -04:00
util.c	mm: use memdup_user	2010-08-09 20:44:54 -07:00
vmalloc.c	mm: use ERR_CAST	2010-08-09 20:44:54 -07:00
vmscan.c	mm/vmscan.c: fix mapping use after free	2010-07-20 16:25:40 -07:00
vmstat.c	mm: compaction: direct compact when a high-order allocation fails	2010-05-25 08:06:59 -07:00