Commit Graph

148 Commits

Author SHA1 Message Date
Linus Torvalds a3fe778c78 Frontswap provides a "transcendent memory" interface for swap pages.
In some environments, dramatic performance savings may be obtained because
 swapped pages are saved in RAM (or a RAM-like device) instead of a swap disk.
 This tag provides the basic infrastructure along with some changes to the
 existing backends.
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Merge tag 'stable/frontswap.v16-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm

Pull frontswap feature from Konrad Rzeszutek Wilk:
 "Frontswap provides a "transcendent memory" interface for swap pages.
  In some environments, dramatic performance savings may be obtained
  because swapped pages are saved in RAM (or a RAM-like device) instead
  of a swap disk.  This tag provides the basic infrastructure along with
  some changes to the existing backends."

Fix up trivial conflict in mm/Makefile due to removal of swap token code
changing a line next to the new frontswap entry.

This pull request came in before the merge window even opened, it got
delayed to after the merge window by me just wanting to make sure it had
actual users.  Apparently IBM is using this on their embedded side, and
Jan Beulich says that it's already made available for SLES and OpenSUSE
users.

Also acked by Rik van Riel, and Konrad points to other people liking it
too.  So in it goes.

By Dan Magenheimer (4) and Konrad Rzeszutek Wilk (2)
via Konrad Rzeszutek Wilk
* tag 'stable/frontswap.v16-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm:
  frontswap: s/put_page/store/g s/get_page/load
  MAINTAINER: Add myself for the frontswap API
  mm: frontswap: config and doc files
  mm: frontswap: core frontswap functionality
  mm: frontswap: core swap subsystem hooks and headers
  mm: frontswap: add frontswap header file
2012-06-04 12:28:45 -07:00
Linus Torvalds af4f8ba31a Merge branch 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux
Pull slab updates from Pekka Enberg:
 "Mainly a bunch of SLUB fixes from Joonsoo Kim"

* 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux:
  slub: use __SetPageSlab function to set PG_slab flag
  slub: fix a memory leak in get_partial_node()
  slub: remove unused argument of init_kmem_cache_node()
  slub: fix a possible memory leak
  Documentations: Fix slabinfo.c directory in vm/slub.txt
  slub: fix incorrect return type of get_any_partial()
2012-06-01 16:50:23 -07:00
Konstantin Khlebnikov 052fb0d635 proc: report file/anon bit in /proc/pid/pagemap
This is an implementation of Andrew's proposal to extend the pagemap file
bits to report what is missing about tasks' working set.

The problem with the working set detection is multilateral.  In the criu
(checkpoint/restore) project we dump the tasks' memory into image files
and to do it properly we need to detect which pages inside mappings are
really in use.  The mincore syscall I though could help with this did not.
 First, it doesn't report swapped pages, thus we cannot find out which
parts of anonymous mappings to dump.  Next, it does report pages from page
cache as present even if they are not mapped, and it doesn't make that has
not been cow-ed.

Note, that issue with swap pages is critical -- we must dump swap pages to
image file.  But the issues with file pages are optimization -- we can
take all file pages to image, this would be correct, but if we know that a
page is not mapped or not cow-ed, we can remove them from dump file.  The
dump would still be self-consistent, though significantly smaller in size
(up to 10 times smaller on real apps).

Andrew noticed, that the proc pagemap file solved 2 of 3 above issues --
it reports whether a page is present or swapped and it doesn't report not
mapped page cache pages.  But, it doesn't distinguish cow-ed file pages
from not cow-ed.

I would like to make the last unused bit in this file to report whether the
page mapped into respective pte is PageAnon or not.

[comment stolen from Pavel Emelyanov's v1 patch]

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: 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>
2012-05-31 17:49:29 -07:00
Mel Gorman 692569946f mm: document the meminfo and vmstat fields of relevance to transparent hugepages
Update Documentation/vm/transhuge.txt and
Documentation/filesystems/proc.txt with some information on monitoring
transparent huge page usage and the associated overhead.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29 16:22:23 -07:00
Konrad Rzeszutek Wilk 165c8aed5b frontswap: s/put_page/store/g s/get_page/load
Sounds so much more natural.

Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-15 11:34:08 -04:00
Dan Magenheimer 27c6aec214 mm: frontswap: config and doc files
This patch 4of4 adds configuration and documentation files including a FAQ.

[v14: updated docs/FAQ to use zcache and RAMster as examples]
[v10: no change]
[v9: akpm@linux-foundation.org: sysfs->debugfs; no longer need Doc/ABI file]
[v8: rebase to 3.0-rc4]
[v7: rebase to 3.0-rc3]
[v6: rebase to 3.0-rc1]
[v5: change config default to n]
[v4: rebase to 2.6.39]
Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Acked-by: Jan Beulich <JBeulich@novell.com>
Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Rik Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-15 11:34:03 -04:00
majianpeng 9fe496116e Documentations: Fix slabinfo.c directory in vm/slub.txt
Because the place of slabinfo.c changed.So update in slub.txt.

Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2012-05-10 11:45:23 +03:00
Dave Young f0f57b2b14 mm: move hugepage test examples to tools/testing/selftests/vm
hugepage-mmap.c, hugepage-shm.c and map_hugetlb.c in Documentation/vm are
simple pass/fail tests, It's better to promote them to
tools/testing/selftests.

Thanks suggestion of Andrew Morton about this.  They all need firstly
setting up proper nr_hugepages and hugepage-mmap need to mount hugetlbfs.
So I add a shell script run_vmtests to do such work which will call the
three test programs and check the return value of them.

Changes to original code including below:
a. add run_vmtests script
b. return error when read_bytes mismatch with writed bytes.
c. coding style fixes: do not use assignment in if condition

[akpm@linux-foundation.org: build the targets before trying to execute them]
[akpm@linux-foundation.org: Documentation/vm/ no longer has a Makefile. Fixes "make clean"]
Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28 17:14:37 -07:00
Dave Young c6dd897f3b mm: move page-types.c from Documentation to tools/vm
tools/ is the better place for vm tools which are used by many people.
Moving them to tools also make them open to more users instead of hide in
Documentation folder.

This patch moves page-types.c to tools/vm/page-types.c.  Also add a
Makefile in tools/vm and fix two coding style problems: a) change const
arrary to 'const char * const', b) change a space to tab for indent.

Signed-off-by: Dave Young <dyoung@redhat.com>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28 17:14:37 -07:00
Linus Torvalds aab008db80 Cleanups: rename of flush to invalidate, moving reporting of statistics
into debugfs, and use __read_mostly as neccessary.
 Also add a MAINTAINER file for cleancache API files.
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Merge tag 'stable/for-linus-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm

Pull cleancache changes from Konrad Rzeszutek Wilk:
 "This has some patches for the cleancache API that should have been
  submitted a _long_ time ago.  They are basically cleanups:

   - rename of flush to invalidate

   - moving reporting of statistics into debugfs

   - use __read_mostly as necessary.

  Oh, and also the MAINTAINERS file change.  The files (except the
  MAINTAINERS file) have been in #linux-next for months now.  The late
  addition of MAINTAINERS file is a brain-fart on my side - didn't
  realize I needed that just until I was typing this up - and I based
  that patch on v3.3 - so the tree is on top of v3.3."

* tag 'stable/for-linus-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm:
  MAINTAINERS: Adding cleancache API to the list.
  mm: cleancache: Use __read_mostly as appropiate.
  mm: cleancache: report statistics via debugfs instead of sysfs.
  mm: zcache/tmem/cleancache: s/flush/invalidate/
  mm: cleancache: s/flush/invalidate/
2012-03-22 19:52:47 -07:00
Naoya Horiguchi 807f0ccfe1 pagemap: document KPF_THP and make page-types aware of it
page-types, which is a common user of pagemap, gets aware of thp with this
patch.  This helps system admins and kernel hackers know about how thp
works.  Here is a sample output of page-types over a thp:

  $ page-types -p <pid> --raw --list

  voffset offset  len     flags
  ...
  7f9d40200       3f8400  1       ___U_lA____Ma_bH______t____________
  7f9d40201       3f8401  1ff     ________________T_____t____________

               flags      page-count       MB  symbolic-flags                     long-symbolic-flags
  0x0000000000410000             511        1  ________________T_____t____________        compound_tail,thp
  0x000000000040d868               1        0  ___U_lA____Ma_bH______t____________        uptodate,lru,active,mmap,anonymous,swapbacked,compound_head,thp

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:57 -07:00
Konrad Rzeszutek Wilk 16c0cfa425 Merge branch 'stable/cleancache.v13' into linux-next
* stable/cleancache.v13:
  mm: cleancache: Use __read_mostly as appropiate.
  mm: cleancache: report statistics via debugfs instead of sysfs.
  mm: zcache/tmem/cleancache: s/flush/invalidate/
  mm: cleancache: s/flush/invalidate/
2012-03-19 12:12:19 -04:00
Masanari Iida 40e47125e6 Documentation: Fix multiple typo in Documentation
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-03-07 16:08:24 +01:00
Masanari Iida d65657c862 mm: Fix typo in cleancache.txt
Correct spelling "implementatation" to "implementation" in
Documentation/vm/cleancache.txt

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-02-10 09:52:18 +01:00
Masanari Iida 3cd0b6252e mm: Fix typo in unevictable-lru.txt
Correct spelling "semphore" to "semaphore" in
Documentation/vm/unevictable-lru.txt

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-02-09 23:09:53 +01:00
Dan Magenheimer 417fc2caef mm: cleancache: report statistics via debugfs instead of sysfs.
[v9: akpm@linux-foundation.org: sysfs->debugfs; no longer need Doc/ABI file]

Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Konrad Wilk <konrad.wilk@oracle.com>
Cc: Jan Beulich <JBeulich@novell.com>
Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Rik Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
2012-01-23 16:07:50 -05:00
Dan Magenheimer 3167760f83 mm: cleancache: s/flush/invalidate/
Per akpm suggestions alter the use of the term flush to be
invalidate. The next patch will do this across all MM.

This change is completely cosmetic.

[v9: akpm@linux-foundation.org: change "flush" to "invalidate", part 3]

Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@novell.com>
Reviewed-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Rik Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
[v10: Fixed  fs: move code out of buffer.c conflict change]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-23 16:06:24 -05:00
Stanislaw Gruszka 888a214dc4 slub: document setting min order with debug_guardpage_minorder > 0
Acked-by: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:04 -08:00
Eric Dumazet 25f4379b8c slub: fix slub_max_order Documentation
slub_max_order default is 3 (aka PAGE_ALLOC_COSTLY_ORDER), not 1

Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-11-27 22:08:28 +02:00
Pekka Enberg e182a345d4 Merge branches 'slab/next' and 'slub/partial' into slab/for-linus 2011-10-26 18:09:12 +03:00
Linus Torvalds 59e5253417 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (59 commits)
  MAINTAINERS: linux-m32r is moderated for non-subscribers
  linux@lists.openrisc.net is moderated for non-subscribers
  Drop default from "DM365 codec select" choice
  parisc: Kconfig: cleanup Kernel page size default
  Kconfig: remove redundant CONFIG_ prefix on two symbols
  cris: remove arch/cris/arch-v32/lib/nand_init.S
  microblaze: add missing CONFIG_ prefixes
  h8300: drop puzzling Kconfig dependencies
  MAINTAINERS: microblaze-uclinux@itee.uq.edu.au is moderated for non-subscribers
  tty: drop superfluous dependency in Kconfig
  ARM: mxc: fix Kconfig typo 'i.MX51'
  Fix file references in Kconfig files
  aic7xxx: fix Kconfig references to READMEs
  Fix file references in drivers/ide/
  thinkpad_acpi: Fix printk typo 'bluestooth'
  bcmring: drop commented out line in Kconfig
  btmrvl_sdio: fix typo 'btmrvl_sdio_sd6888'
  doc: raw1394: Trivial typo fix
  CIFS: Don't free volume_info->UNC until we are entirely done with it.
  treewide: Correct spelling of successfully in comments
  ...
2011-10-25 12:11:02 +02:00
Paul Bolle 395cf9691d doc: fix broken references
There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.

Fix these broken references, sometimes by dropping the irrelevant text
they were part of.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-27 18:08:04 +02:00
David Rientjes e369fde1af thp: fix khugepaged defrag tunable documentation
Commit e27e6151b1 ("mm/thp: use conventional format for boolean
attributes") changed

  /sys/kernel/mm/transparent_hugepage/khugepaged/defrag

to be tuned by using 1 (enabled) or 0 (disabled) instead of "yes" and
"no", respectively.

Update the documentation.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-22 14:27:14 -07:00
Jason Liu a37933c37c slub: doc: update the slabinfo.c file path
slabinfo.c has been moved from Documentaion/vm/ to
tools/slub/ by commit:0d24db337e6d81c0c620ab65cc6947bd6553f742

Update the slub.txt doc to reflect this change too.

Signed-off-by: Jason Liu <jason.hui@linaro.org>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-08-31 20:10:17 +03:00
Jörg Sommer f6e07d3807 Documentation: update cgroupfs mount point
According to commit 676db4af04 ("cgroupfs: create /sys/fs/cgroup to
mount cgroupfs on") the canonical mountpoint for the cgroup filesystem
is /sys/fs/cgroup.  Hence, this should be used in the documentation.

Signed-off-by: Jörg Sommer <joerg@alea.gnuu.de>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-15 21:52:50 -07:00
Linus Torvalds f8d613e2a6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem:
  xen: cleancache shim to Xen Transcendent Memory
  ocfs2: add cleancache support
  ext4: add cleancache support
  btrfs: add cleancache support
  ext3: add cleancache support
  mm/fs: add hooks to support cleancache
  mm: cleancache core ops functions and config
  fs: add field to superblock to support cleancache
  mm/fs: cleancache documentation

Fix up trivial conflict in fs/btrfs/extent_io.c due to includes
2011-05-26 10:50:56 -07:00
Dan Magenheimer 4fe4746ab6 mm/fs: cleancache documentation
This patchset introduces cleancache, an optional new feature exposed
by the VFS layer that potentially dramatically increases page cache
effectiveness for many workloads in many environments at a negligible
cost.  It does this by providing an interface to transcendent memory,
which is memory/storage that is not otherwise visible to and/or directly
addressable by the kernel.

Instead of being discarded, hooks in the reclaim code "put" clean
pages to cleancache.  Filesystems that "opt-in" may "get" pages
from cleancache that were previously put, but pages in cleancache are
"ephemeral", meaning they may disappear at any time. And the size
of cleancache is entirely dynamic and unknowable to the kernel.
Filesystems currently supported by this patchset include ext3, ext4,
btrfs, and ocfs2.  Other filesystems (especially those built entirely
on VFS) should be easy to add, but should first be thoroughly tested to
ensure coherency.

Details and a FAQ are provided in Documentation/vm/cleancache.txt

This first patch of eight in this cleancache series only adds two
new documentation files.

[v8: minor documentation changes by author]
[v3: akpm@linux-foundation.org: document sysfs API]
[v3: hch@infradead.org: move detailed description to Documentation/vm]
Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Reviewed-by: Jeremy Fitzhardinge <jeremy@goop.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik Van Riel <riel@redhat.com>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Andreas Dilger <adilger@sun.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Nitin Gupta <ngupta@vflare.org>
2011-05-26 10:00:56 -06:00
Peter Zijlstra 3d48ae45e7 mm: Convert i_mmap_lock to a mutex
Straightforward conversion of i_mmap_lock to a mutex.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Tony Luck <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:18 -07:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Chen Gong 12da58b0c8 Documentation/vm/page-types.c: auto debugfs mount for hwpoison operation
page-types.c doesn't supply a way to specify the debugfs path and the
original debugfs path is not usual on most machines.  This patch supplies
a way to auto mount debugfs if needed.

This patch is heavily inspired by tools/perf/utils/debugfs.c

[akpm@linux-foundation.org: make functions static]
[akpm@linux-foundation.org: fix debugfs_mount() signature]
Signed-off-by: Chen Gong <gong.chen@linux.intel.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:17 -07:00
Michal Hocko e6e8dd5055 doc: CONFIG_UNEVICTABLE_LRU doesn't exist anymore
commit 6837765963 ("mm: remove CONFIG_UNEVICTABLE_LRU config option")
has removed the configoption so we should sync up the doc as well.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-03-17 00:37:19 +01:00
Andrea Arcangeli 1c9bf22c09 thp: transparent hugepage support documentation
Documentation/vm/transhuge.txt

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:38 -08:00
Pekka Enberg 716ce5d4a6 slub: Fix build breakage in Documentation/vm
This patch fixes a build breakage introduced by commit
f5ac4916e9840292edd33c7a52b10364526547f3 ("slub: move slabinfo.c to
tools/slub/slabinfo.c") that was repoted by Stephen:

  After merging the slab tree, today's linux-next build (x86_64 allmodconfig)
  failed like this:

  gcc: /scratch/sfr/next/Documentation/vm/slabinfo.c: No such file or directory
  gcc: no input files

  Caused by commit f5ac4916e9840292edd33c7a52b10364526547f3 ("slub: move
  slabinfo.c to tools/slub/slabinfo.c").  Missing update to
  Documentation/vm/Makefile?

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2010-11-06 09:04:33 +02:00
Christoph Lameter 0d24db337e slub: move slabinfo.c to tools/slub/slabinfo.c
We now have a tools directory for these things.

Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2010-11-06 09:04:32 +02:00
Peter Zijlstra d65bfacb04 mm: highmem documentation
Document outlining some of the highmem issues, started by me, edited by
David.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:08 -07:00
Linus Torvalds 229aebb873 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
  Update broken web addresses in arch directory.
  Update broken web addresses in the kernel.
  Revert "drivers/usb: Remove unnecessary return's from void functions" for musb gadget
  Revert "Fix typo: configuation => configuration" partially
  ida: document IDA_BITMAP_LONGS calculation
  ext2: fix a typo on comment in ext2/inode.c
  drivers/scsi: Remove unnecessary casts of private_data
  drivers/s390: Remove unnecessary casts of private_data
  net/sunrpc/rpc_pipe.c: Remove unnecessary casts of private_data
  drivers/infiniband: Remove unnecessary casts of private_data
  drivers/gpu/drm: Remove unnecessary casts of private_data
  kernel/pm_qos_params.c: Remove unnecessary casts of private_data
  fs/ecryptfs: Remove unnecessary casts of private_data
  fs/seq_file.c: Remove unnecessary casts of private_data
  arm: uengine.c: remove C99 comments
  arm: scoop.c: remove C99 comments
  Fix typo configue => configure in comments
  Fix typo: configuation => configuration
  Fix typo interrest[ing|ed] => interest[ing|ed]
  Fix various typos of valid in comments
  ...

Fix up trivial conflicts in:
	drivers/char/ipmi/ipmi_si_intf.c
	drivers/usb/gadget/rndis.c
	net/irda/irnet/irnet_ppp.c
2010-10-24 13:41:39 -07:00
Naoya Horiguchi 6715981312 page-types.c: fix name of unpoison interface
The page-types utility still uses an out of date name for the
unpoison interface: debugfs:hwpoison/renew-pfn
This patch renames and fixes it.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
2010-10-07 09:41:24 +02:00
Nikanth Karthikesan 0bc79f7f58 Doc: Fix typo s/packages/packaged
Fix typo s/packages/packaged in Documentation/vm/numa_memory_policy.txt.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-09-21 17:03:27 +02:00
Tommi Rantala c7825cfac6 Documentation/vm: fix spelling in page-types.c
Trivial typo fixes.

Signed-off-by: Tommi Rantala <tt.rantala@gmail.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-05 13:21:23 -07:00
Lee Schermerhorn b9498bfe86 numa: update Documentation/vm/numa, add memoryless node info
Kamezawa Hiroyuki requested documentation for the numa_mem_id() and slab
related changes.  He suggested Documentation/vm/numa for this
documentation.  Looking at this file, it seems to me to be hopelessly out
of date relative to current Linux NUMA support.  At the risk of going down
a rathole, I have made an attempt to rewrite the doc at a slightly higher
level [I think] and provide pointers to other in-tree documents and
out-of-tree man pages that cover the details.

Let the games begin.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Whitney <eric.whitney@hp.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:57 -07:00
Carlo Marcelo Arenas Belon 89bbfb6bfb Documentation/vm: use better value for MAP_HUGETLB
documentation: slightly more correct value for MAP_HUGETLB in map_hugetlb.c

still not correct for alpha, mips, parisc or xtensa but working out of
the box in the most common architectures without having to deal with
complicated macros or including architecture specific headers.

Signed-off-by: Carlo Marcelo Arenas Belon <carenas@sajinet.com.pe>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-24 07:30:56 -07:00
Francis Galiegue a33f32244d Documentation/: it's -> its where appropriate
Fix obvious cases of "it's" being used when "its" was meant.

Signed-off-by: Francis Galiegue <fgaliegue@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-04-23 02:09:52 +02:00
Randy Dunlap 70bace8c1e Documentation/vm/: split txt and source files
Documentation/vm/:
Expose example and tool source files in the Documentation/ directory in
their own files instead of being buried (almost hidden) in readme/txt files.
This should help to prevent bitrot.

This will make them more visible/usable to users who may need
to use them, to developers who may need to test with them, and
to anyone who would fix/update them if they were more visible.

Also, if any of these possibly should not be in the kernel tree at
all, it will be clearer that they are here and we can discuss if
they should be removed.

Also build the recently-added map_hugetlb.c.
Make several functions static to prevent linker warnings.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Eric B Munson <ebmunson@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:35 -08:00
Dmitry Monakhov 4c13dd3b48 failslab: add ability to filter slab caches
This patch allow to inject faults only for specific slabs.
In order to preserve default behavior cache filter is off by
default (all caches are faulty).

One may define specific set of slabs like this:
# mark skbuff_head_cache as faulty
echo 1 > /sys/kernel/slab/skbuff_head_cache/failslab
# Turn on cache filter (off by default)
echo 1 > /sys/kernel/debug/failslab/cache-filter
# Turn on fault injection
echo 1 > /sys/kernel/debug/failslab/times
echo 1 > /sys/kernel/debug/failslab/probability

Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2010-02-26 19:19:39 +02:00
Andi Kleen fe194d3e10 HWPOISON: Use correct name for MADV_HWPOISON in documentation
Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-12-16 12:20:00 +01:00
Andi Kleen 4fd466eb46 HWPOISON: add memory cgroup filter
The hwpoison test suite need to inject hwpoison to a collection of
selected task pages, and must not touch pages not owned by them and
thus kill important system processes such as init. (But it's OK to
mis-hwpoison free/unowned pages as well as shared clean pages.
Mis-hwpoison of shared dirty pages will kill all tasks, so the test
suite will target all or non of such tasks in the first place.)

The memory cgroup serves this purpose well. We can put the target
processes under the control of a memory cgroup, and tell the hwpoison
injection code to only kill pages associated with some active memory
cgroup.

The prerequisite for doing hwpoison stress tests with mem_cgroup is,
the mem_cgroup code tracks task pages _accurately_ (unless page is
locked).  Which we believe is/should be true.

The benefits are simplification of hwpoison injector code. Also the
mem_cgroup code will automatically be tested by hwpoison test cases.

The alternative interfaces pin-pfn/unpin-pfn can also delegate the
(process and page flags) filtering functions reliably to user space.
However prototype implementation shows that this scheme adds more
complexity than we wanted.

Example test case:

	mkdir /cgroup/hwpoison

	usemem -m 100 -s 1000 &
	echo `jobs -p` > /cgroup/hwpoison/tasks

	memcg_ino=$(ls -id /cgroup/hwpoison | cut -f1 -d' ')
	echo $memcg_ino > /debug/hwpoison/corrupt-filter-memcg

	page-types -p `pidof init`   --hwpoison  # shall do nothing
	page-types -p `pidof usemem` --hwpoison  # poison its pages

[AK: Fix documentation]
[Add fix for problem noticed by Li Zefan <lizf@cn.fujitsu.com>;
dentry in the css could be NULL]

CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
CC: Hugh Dickins <hugh.dickins@tiscali.co.uk>
CC: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
CC: Balbir Singh <balbir@linux.vnet.ibm.com>
CC: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
CC: Li Zefan <lizf@cn.fujitsu.com>
CC: Paul Menage <menage@google.com>
CC: Nick Piggin <npiggin@suse.de>
CC: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-12-16 12:19:59 +01:00
Wu Fengguang 478c5ffc0b HWPOISON: add page flags filter
When specified, only poison pages if ((page_flags & mask) == value).

-       corrupt-filter-flags-mask
-       corrupt-filter-flags-value

This allows stress testing of many kinds of pages.

Strictly speaking, the buddy pages requires taking zone lock, to avoid
setting PG_hwpoison on a "was buddy but now allocated to someone" page.
However we can just do nothing because we set PG_locked in the beginning,
this prevents the page allocator from allocating it to someone. (It will
BUG() on the unexpected PG_locked, which is fine for hwpoison testing.)

[AK: Add select PROC_PAGE_MONITOR to satisfy dependency]

CC: Nick Piggin <npiggin@suse.de>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-12-16 12:19:59 +01:00
Wu Fengguang 31d3d3484f HWPOISON: limit hwpoison injector to known page types
__memory_failure()'s workflow is

	set PG_hwpoison
	//...
	unset PG_hwpoison if didn't pass hwpoison filter

That could kill unrelated process if it happens to page fault on the
page with the (temporary) PG_hwpoison. The race should be big enough to
appear in stress tests.

Fix it by grabbing the page and checking filter at inject time.  This
also avoids the very noisy "Injecting memory failure..." messages.

- we don't touch madvise() based injection, because the filters are
  generally not necessary for it.
- if we want to apply the filters to h/w aided injection, we'd better to
  rearrange the logic in __memory_failure() instead of this patch.

AK: fix documentation, use drain all, cleanups

CC: Haicheng Li <haicheng.li@intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-12-16 12:19:59 +01:00
Wu Fengguang 7c116f2b0d HWPOISON: add fs/device filters
Filesystem data/metadata present the most tricky-to-isolate pages.
It requires careful code review and stress testing to get them right.

The fs/device filter helps to target the stress tests to some specific
filesystem pages. The filter condition is block device's major/minor
numbers:
        - corrupt-filter-dev-major
        - corrupt-filter-dev-minor
When specified (non -1), only page cache pages that belong to that
device will be poisoned.

The filters are checked reliably on the locked and refcounted page.

Haicheng: clear PG_hwpoison and drop bad page count if filter not OK
AK: Add documentation

CC: Haicheng Li <haicheng.li@intel.com>
CC: Nick Piggin <npiggin@suse.de>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-12-16 12:19:59 +01:00
Wu Fengguang 847ce401df HWPOISON: Add unpoisoning support
The unpoisoning interface is useful for stress testing tools to
reclaim poisoned pages (to prevent OOM)

There is no hardware level unpoisioning, so this
cannot be used for real memory errors, only for software injected errors.

Note that it may leak pages silently - those who have been removed from
LRU cache, but not isolated from page cache/swap cache at hwpoison time.
Especially the stress test of dirty swap cache pages shall reboot system
before exhausting memory.

AK: Fix comments, add documentation, add printks, rename symbol

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-12-16 12:19:58 +01:00