Hugh Dickins 80e1482260 ksm: share anon page without allocating ... When ksm pages were unswappable, it made no sense to include them in mem cgroup accounting; but now that they are swappable (although I see no strict logical connection) the principle of least surprise implies that they should be accounted (with the usual dissatisfaction, that a shared page is accounted to only one of the cgroups using it). This patch was intended to add mem cgroup accounting where necessary; but turned inside out, it now avoids allocating a ksm page, instead upgrading an anon page to ksm - which brings its existing mem cgroup accounting with it. Thus mem cgroups don't appear in the patch at all. This upgrade from PageAnon to PageKsm takes place under page lock (via a somewhat hacky NULL kpage interface), and audit showed only one place which needed to cope with the race - page_referenced() is sometimes used without page lock, so page_lock_anon_vma() needs an ACCESS_ONCE() to be sure of getting anon_vma and flags together (no problem if the page goes ksm an instant after, the integrity of that anon_vma list is unaffected). Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: Izik Eidus <ieidus@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Chris Wright <chrisw@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2009-12-15 08:53:19 -08:00
..
backing-dev.c
bootmem.c
bounce.c
debug-pagealloc.c
dmapool.c
fadvise.c
failslab.c
filemap_xip.c
filemap.c
fremap.c
highmem.c
hugetlb.c
hwpoison-inject.c
init-mm.c
internal.h	ksm: fix mlockfreed to munlocked	2009-12-15 08:53:19 -08:00
Kconfig	mm: stop ptlock enlarging struct page	2009-12-15 08:53:17 -08:00
Kconfig.debug
kmemcheck.c
kmemleak-test.c
kmemleak.c
ksm.c	ksm: share anon page without allocating	2009-12-15 08:53:19 -08:00
maccess.c
madvise.c
Makefile
memcontrol.c
memory_hotplug.c
memory-failure.c	mm: CONFIG_MMU for PG_mlocked	2009-12-15 08:53:17 -08:00
memory.c	ksm: let shared pages be swappable	2009-12-15 08:53:19 -08:00
mempolicy.c
mempool.c
migrate.c
mincore.c
mlock.c	ksm: fix mlockfreed to munlocked	2009-12-15 08:53:19 -08:00
mm_init.c
mmap.c
mmu_context.c
mmu_notifier.c
mmzone.c
mprotect.c
mremap.c
msync.c
nommu.c
oom_kill.c
page_alloc.c	mm: CONFIG_MMU for PG_mlocked	2009-12-15 08:53:17 -08:00
page_cgroup.c
page_io.c
page_isolation.c
page-writeback.c
pagewalk.c
percpu.c
prio_tree.c
quicklist.c
readahead.c
rmap.c	ksm: share anon page without allocating	2009-12-15 08:53:19 -08:00
shmem_acl.c
shmem.c
slab.c
slob.c
slub.c
sparse-vmemmap.c
sparse.c
swap_state.c
swap.c
swapfile.c	ksm: let shared pages be swappable	2009-12-15 08:53:19 -08:00
thrash.c
truncate.c
util.c
vmalloc.c
vmscan.c	vmscan: make consistent of reclaim bale out between do_try_to_free_page and shrink_zone	2009-12-15 08:53:18 -08:00
vmstat.c