Commit Graph

97 Commits

Author SHA1 Message Date
Hugh Dickins
d0f209f68f ksm: remove unswappable max_kernel_pages
Now that ksm pages are swappable, and the known holes plugged, remove
mention of unswappable kernel pages from KSM documentation and comments.

Remove the totalram_pages/4 initialization of max_kernel_pages.  In fact,
remove max_kernel_pages altogether - we can reinstate it if removal turns
out to break someone's script; but if we later want to limit KSM's memory
usage, limiting the stable nodes would not be an effective approach.

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 08:53:20 -08:00
Lee Schermerhorn
4faf8d950e hugetlb: handle memory hot-plug events
Register per node hstate attributes only for nodes with memory.  As
suggested by David Rientjes.

With Memory Hotplug, memory can be added to a memoryless node and a node
with memory can become memoryless.  Therefore, add a memory on/off-line
notifier callback to [un]register a node's attributes on transition
to/from memoryless state.

N.B.,  Only tested build, boot, libhugetlbfs regression.
       i.e., no memory hotplug testing.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Reviewed-by: Andi Kleen <andi@firstfloor.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Nishanth Aravamudan <nacc@us.ibm.com>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Eric Whitney <eric.whitney@hp.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:13 -08:00
Lee Schermerhorn
9b5e5d0fdc hugetlb: use only nodes with memory for huge pages
Register per node hstate sysfs attributes only for nodes with memory.
Global replacement of 'all online nodes" with "all nodes with memory" in
mm/hugetlb.c.  Suggested by David Rientjes.

A subsequent patch will handle adding/removing of per node hstate sysfs
attributes when nodes transition to/from memoryless state via memory
hotplug.

NOTE: this patch has not been tested with memoryless nodes.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Reviewed-by: Andi Kleen <andi@firstfloor.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Nishanth Aravamudan <nacc@us.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Eric Whitney <eric.whitney@hp.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:13 -08:00
Lee Schermerhorn
267b4c281b hugetlb: update hugetlb documentation for NUMA controls
Update the kernel huge tlb documentation to describe the numa memory
policy based huge page management.  Additionaly, the patch includes a fair
amount of rework to improve consistency, eliminate duplication and set the
context for documenting the memory policy interaction.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Andi Kleen <andi@firstfloor.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Nishanth Aravamudan <nacc@us.ibm.com>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Eric Whitney <eric.whitney@hp.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:12 -08:00
Alex Chiang
bb86a7338b page-types: exit early when invoked with -d|--describe
On a system with large amount of memory (256GB), invoking page-types can
take quite a long time, which is unreasonable considering the user only
wants a description of the flags:

	# time ./page-types -d 0x10
	0x0000000000000010	____D_____________________________	dirty

	real	0m34.285s
	user	0m1.966s
	sys	0m32.313s

This is because we still walk the entire address range.

Exiting early seems like a reasonble solution:

# time ./page-types -d 0x10
	0x0000000000000010	____D_____________________________	dirty

	real	0m0.007s
	user	0m0.001s
	sys	0m0.005s

Signed-off-by: Alex Chiang <achiang@hp.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Haicheng Li <haicheng.li@intel.com>
Acked-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>
2009-12-15 08:53:11 -08:00
Alex Chiang
9fdcd886ab page-types: whitespace alignment
Align the output when page-type -h is invoked.

Signed-off-by: Alex Chiang <achiang@hp.com>
Acked-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>
2009-12-15 08:53:11 -08:00
Alex Chiang
dcfe730c60 page-types: learn to describe flags directly from command line
Teach page-types to describe page flags directly from the command line.

Why is this useful?  For instance, if you're using memory hotplug and see
this in /var/log/messages:

	kernel: removing from LRU failed 3836dd0/1/1e00000000000010

It would be nice to decode those page flags without staring at the source.

Example usage and output:

# Documentation/vm/page-types -d 0x10
0x0000000000000010	____D_____________________________	dirty

# Documentation/vm/page-types -d anon
0x0000000000001000	____________a_____________________	anonymous

# Documentation/vm/page-types -d anon,0x10
0x0000000000001010	____D_______a_____________________	dirty,anonymous

[achiang@hp.com: documentation]
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Haicheng Li <haicheng.li@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:11 -08:00
Roel Kluin
f1327bf18c page-types: unsigned cannot be less than 0 in add_page()
If not signed, testing of the read() return value in this function
will not work.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:11 -08:00
Tommi Rantala
3428838d8e page-types: constify read only arrays
Signed-off-by: Tommi Rantala <tt.rantala@gmail.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:10 -08:00
Jiri Kosina
d014d04386 Merge branch 'for-next' into for-linus
Conflicts:

	kernel/irq/chip.c
2009-12-07 18:36:35 +01:00
Justin P. Mattock
e02f0e868a doc: Fix a typo in slub.txt.
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-12-04 15:39:59 +01:00
André Goddard Rosa
af901ca181 tree-wide: fix assorted typos all over the place
That is "success", "unknown", "through", "performance", "[re|un]mapping"
, "access", "default", "reasonable", "[con]currently", "temperature"
, "channel", "[un]used", "application", "example","hierarchy", "therefore"
, "[over|under]flow", "contiguous", "threshold", "enough" and others.

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-12-04 15:39:55 +01:00
Linus Torvalds
cb20c28a9c Merge branch 'hostprogs-wmissing-prototypes' of git://git.kernel.org/pub/scm/linux/kernel/git/josh/linux-misc
* 'hostprogs-wmissing-prototypes' of git://git.kernel.org/pub/scm/linux/kernel/git/josh/linux-misc:
  Makefile: Add -Wmising-prototypes to HOSTCFLAGS
  oss: Mark loadhex static in hex2hex.c
  dtc: Mark various internal functions static
  dtc: Set "noinput" in the lexer to avoid an unused function
  drm: radeon: Mark several functions static in mkregtable
  arch/sparc/boot/*.c: Mark various internal functions static
  arch/powerpc/boot/addRamDisk.c: Mark several internal functions static
  arch/alpha/boot/tools/objstrip.c: Mark "usage" static
  Documentation/vm/page-types.c: Declare checked_open static
  genksyms: Mark is_reserved_word static
  kconfig: Mark various internal functions static
  kconfig: Make zconf.y work with current bison
2009-11-17 09:14:49 -08:00
Josh Triplett
1b98c00bf3 Documentation/vm/page-types.c: Declare checked_open static
Nothing outside of Documentation/vm/page-types.c references
checked_open.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
2009-11-15 15:01:38 -08:00
Linus Torvalds
3242f9804b Merge branch 'hwpoison-2.6.32' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
* 'hwpoison-2.6.32' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6:
  HWPOISON: fix invalid page count in printk output
  HWPOISON: Allow schedule_on_each_cpu() from keventd
  HWPOISON: fix/proc/meminfo alignment
  HWPOISON: fix oops on ksm pages
  HWPOISON: Fix page count leak in hwpoison late kill in do_swap_page
  HWPOISON: return early on non-LRU pages
  HWPOISON: Add brief hwpoison description to Documentation
  HWPOISON: Clean up PR_MCE_KILL interface
2009-10-29 08:20:00 -07:00
Wu Fengguang
a54fed9f70 page-types: add hwpoison/unpoison feature
For hwpoison stress testing.  The debugfs mount point is assumed to be
/debug/.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08 07:36:39 -07:00
Wu Fengguang
48640d69f5 page-types: introduce kpageflags_flags()
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08 07:36:39 -07:00
Wu Fengguang
e577ebde9f page-types: make voffset local variables
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08 07:36:39 -07:00
Wu Fengguang
4a1b6726fe page-types: make standalone pagemap/kpageflags read routines
Refactor the code to be more modular and easier to reuse.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08 07:36:39 -07:00
Wu Fengguang
31bbf66eaa page-types: introduce checked_open()
This helps merge duplicate code (now and future) and outstand the main
logic.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08 07:36:39 -07:00
Wu Fengguang
0c57effe27 page-types: add GPL note
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08 07:36:39 -07:00
Wu Fengguang
a1bbb5ec39 pagemap: document KPF_KSM and show it in page-types
It indicates to the system admin that processes mapping such pages may be
eating less physical memory than the reported numbers by legacy tools.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Izik Eidus <ieidus@redhat.com>
Acked-by: Chris Wright <chrisw@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08 07:36:39 -07:00
Wu Fengguang
253fb02d62 pagemap: export KPF_HWPOISON
This flag indicates a hardware detected memory corruption on the page.
Any future access of the page data may bring down the machine.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08 07:36:39 -07:00
Hugh Dickins
c73602ad31 ksm: more on default values
Adjust the max_kernel_pages default to a quarter of totalram_pages,
instead of nr_free_buffer_pages() / 4: the KSM pages themselves come from
highmem, and even on a 16GB PAE machine, 4GB of KSM pages would only be
pinning 32MB of lowmem with their rmap_items, so no need for the more
obscure calculation (nor for its own special init function).

There is no way for the user to switch KSM on if CONFIG_SYSFS is not
enabled, so in that case default run to KSM_RUN_MERGE.

Update KSM Documentation and Kconfig to reflect the new defaults.

Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Izik Eidus <ieidus@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08 07:36:38 -07:00
Andi Kleen
f58ee00f15 HWPOISON: Add brief hwpoison description to Documentation
Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-10-04 03:23:26 +02:00