linux/Documentation/vm
Vladimir Davydov f074a8f49e proc: export idle flag via kpageflags
As noted by Minchan, a benefit of reading idle flag from /proc/kpageflags
is that one can easily filter dirty and/or unevictable pages while
estimating the size of unused memory.

Note that idle flag read from /proc/kpageflags may be stale in case the
page was accessed via a PTE, because it would be too costly to iterate
over all page mappings on each /proc/kpageflags read to provide an
up-to-date value.  To make sure the flag is up-to-date one has to read
/sys/kernel/mm/page_idle/bitmap first.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Greg Thelen <gthelen@google.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10 13:29:01 -07:00
..
.gitignore
00-INDEX mm: introduce idle page tracking 2015-09-10 13:29:01 -07:00
active_mm.txt
balance
cleancache.txt cleancache: forbid overriding cleancache_ops 2015-04-14 16:49:03 -07:00
frontswap.txt doc: fix quite a few typos within Documentation 2012-11-19 14:28:24 +01:00
highmem.txt
hugetlbpage.txt Documentation: update libhugetlbfs location and use for testing 2015-09-08 15:35:28 -07:00
hwpoison.txt mm/memory-failure.c: support use of a dedicated thread to handle SIGBUS(BUS_MCEERR_AO) 2014-06-04 16:54:13 -07:00
idle_page_tracking.txt mm: introduce idle page tracking 2015-09-10 13:29:01 -07:00
ksm.txt ksm: add some comments 2013-02-23 17:50:23 -08:00
numa doc: fix broken references 2011-09-27 18:08:04 +02:00
numa_memory_policy.txt Documentation/vm/numa_memory_policy.txt: fix wrong document in numa_memory_policy.txt 2014-04-18 16:40:08 -07:00
overcommit-accounting mm: add overcommit_kbytes sysctl variable 2014-01-21 16:19:44 -08:00
page_migration
page_owner.txt Documentation: add new page_owner document 2014-12-13 12:42:48 -08:00
pagemap.txt proc: export idle flag via kpageflags 2015-09-10 13:29:01 -07:00
remap_file_pages.txt mm: replace remap_file_pages() syscall with emulation 2015-02-10 14:30:30 -08:00
slub.txt Documentations: Fix slabinfo.c directory in vm/slub.txt 2012-05-10 11:45:23 +03:00
soft-dirty.txt mm: track vma changes with VM_SOFTDIRTY bit 2013-09-11 15:57:56 -07:00
split_page_table_lock x86, mm: do not leak page->ptl for pmd page tables 2013-11-21 16:42:28 -08:00
transhuge.txt doc: add information about max_ptes_none 2015-03-20 07:41:55 -06:00
unevictable-lru.txt Documentation/vm/unevictable-lru.txt: clarify MAP_LOCKED behavior 2015-06-24 17:49:44 -07:00
userfaultfd.txt userfaultfd: change the read API to return a uffd_msg 2015-09-04 16:54:41 -07:00
zsmalloc.txt zsmalloc: zsmalloc documentation 2015-04-15 16:35:21 -07:00
zswap.txt zswap: update docs for runtime-changeable attributes 2015-09-10 13:29:01 -07:00