Joonsoo Kim 8ba00bb68a slub: consider pfmemalloc_match() in get_partial_node() ... get_partial() is currently not checking pfmemalloc_match() meaning that it is possible for pfmemalloc pages to leak to non-pfmemalloc users. This is a problem in the following situation. Assume that there is a request from normal allocation and there are no objects in the per-cpu cache and no node-partial slab. In this case, slab_alloc enters the slow path and new_slab_objects() is called which may return a PFMEMALLOC page. As the current user is not allowed to access PFMEMALLOC page, deactivate_slab() is called ([5091b74a: mm: slub: optimise the SLUB fast path to avoid pfmemalloc checks]) and returns an object from PFMEMALLOC page. Next time, when we get another request from normal allocation, slab_alloc() enters the slow-path and calls new_slab_objects(). In new_slab_objects(), we call get_partial() and get a partial slab which was just deactivated but is a pfmemalloc page. We extract one object from it and re-deactivate. "deactivate -> re-get in get_partial -> re-deactivate" occures repeatedly. As a result, access to PFMEMALLOC page is not properly restricted and it can cause a performance degradation due to frequent deactivation. deactivation frequently. This patch changes get_partial_node() to take pfmemalloc_match() into account and prevents the "deactivate -> re-get in get_partial() scenario. Instead, new_slab() is called. Signed-off-by: Joonsoo Kim <js1304@gmail.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: David Miller <davem@davemloft.net> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2012-09-17 15:00:38 -07:00
..
backing-dev.c	vfs: kill write_super and sync_supers	2012-08-04 01:24:44 +04:00
bootmem.c
bounce.c
cleancache.c
compaction.c	mm: compaction: Abort async compaction if locks are contended or taking too long	2012-08-21 16:45:03 -07:00
debug-pagealloc.c
dmapool.c
fadvise.c
failslab.c
filemap.c	block: move down direct IO plugging	2012-08-09 15:23:09 +02:00
filemap_xip.c
fremap.c
frontswap.c
highmem.c
huge_memory.c
hugetlb.c
hugetlb_cgroup.c
hwpoison-inject.c
init-mm.c
internal.h	mm: compaction: Abort async compaction if locks are contended or taking too long	2012-08-21 16:45:03 -07:00
Kconfig
Kconfig.debug
kmemcheck.c
kmemleak-test.c
kmemleak.c
ksm.c
maccess.c
madvise.c
Makefile
memblock.c	mm/memblock: Use NULL instead of 0 for pointers	2012-09-05 08:32:30 +02:00
memcontrol.c
memory-failure.c
memory.c
memory_hotplug.c
mempolicy.c	Remove user-triggerable BUG from mpol_to_str	2012-09-06 09:37:58 -07:00
mempool.c
migrate.c
mincore.c
mlock.c
mm_init.c
mmap.c	Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2012-08-23 21:48:41 -07:00
mmu_context.c
mmu_notifier.c
mmzone.c
mprotect.c
mremap.c
msync.c
nobootmem.c
nommu.c
oom_kill.c
page-writeback.c	vfs: kill write_super and sync_supers	2012-08-04 01:24:44 +04:00
page_alloc.c	mm: compaction: Abort async compaction if locks are contended or taking too long	2012-08-21 16:45:03 -07:00
page_cgroup.c
page_io.c
page_isolation.c
pagewalk.c
percpu-km.c
percpu-vm.c
percpu.c
pgtable-generic.c
prio_tree.c
process_vm_access.c
quicklist.c
readahead.c
rmap.c
shmem.c
slab.c	slab: fix starting index for finding another object	2012-09-17 15:00:38 -07:00
slab.h
slab_common.c
slob.c
slub.c	slub: consider pfmemalloc_match() in get_partial_node()	2012-09-17 15:00:38 -07:00
sparse-vmemmap.c
sparse.c
swap.c
swap_state.c
swapfile.c
truncate.c
util.c
vmalloc.c
vmscan.c	memory hotplug: reset pgdat->kswapd to NULL if creating kernel thread fails	2012-09-17 15:00:37 -07:00
vmstat.c