Impact: cleanup

Time to clean up remaining laggards using the old cpu_ functions.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Trond.Myklebust@netapp.com

Impact: Use new API

Convert kernel mm functions to use struct cpumask.

We skip include/linux/percpu.h and mm/allocpercpu.c, which are in flux.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>
Reviewed-by: NChristoph Lameter <cl@linux-foundation.org>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Acked-by: NChristoph Lameter <cl@linux-foundation.org>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Acked-by: NChristoph Lameter <cl@linux-foundation.org>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>

Allow free of mlock()ed pages.  This shouldn't happen, but during
developement, it occasionally did.

This patch allows us to survive that condition, while keeping the
statistics and events correct for debug.
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add NR_MLOCK zone page state, which provides a (conservative) count of
mlocked pages (actually, the number of mlocked pages moved off the LRU).

Reworked by lts to fit in with the modified mlock page support in the
Reclaim Scalability series.

[kosaki.motohiro@jp.fujitsu.com: fix incorrect Mlocked field of /proc/meminfo]
[lee.schermerhorn@hp.com: mlocked-pages: add event counting with statistics]
Signed-off-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Report unevictable pages per zone and system wide.

Kosaki Motohiro added support for memory controller unevictable
statistics.

[riel@redhat.com: fix printk in show_free_areas()]
[akpm@linux-foundation.org: fix units in /proc/vmstats]
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Debugged-by: NHiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix to unevictable-lru-page-statistics.patch

Add unevictable lru infrastructure vm events to the statistics patch.
Rename the "NORECL_" and "noreclaim_" symbols and text strings to
"UNEVICTABLE_" and "unevictable_", respectively.

Currently, both the infrastructure and the mlocked pages event are
added by a single patch later in the series.  This makes it difficult
to add or rework the incremental patches.  The events actually "belong"
with the stats, so pull them up to here.

Also, restore the event counting to putback_lru_page().  This was removed
from previous patch in series where it was "misplaced".  The actual events
weren't defined that early.
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We avoid evicting and scanning anonymous pages for the most part, but
under some workloads we can end up with most of memory filled with
anonymous pages.  At that point, we suddenly need to clear the referenced
bits on all of memory, which can take ages on very large memory systems.

We can reduce the maximum number of pages that need to be scanned by not
taking the referenced state into account when deactivating an anonymous
page.  After all, every anonymous page starts out referenced, so why
check?

If an anonymous page gets referenced again before it reaches the end of
the inactive list, we move it back to the active list.

To keep the maximum amount of necessary work reasonable, we scale the
active to inactive ratio with the size of memory, using the formula
active:inactive ratio = sqrt(memory in GB * 10).

Kswapd CPU use now seems to scale by the amount of pageout bandwidth,
instead of by the amount of memory present in the system.

[kamezawa.hiroyu@jp.fujitsu.com: fix OOM with memcg]
[kamezawa.hiroyu@jp.fujitsu.com: memcg: lru scan fix]
Signed-off-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Split the LRU lists in two, one set for pages that are backed by real file
systems ("file") and one for pages that are backed by memory and swap
("anon").  The latter includes tmpfs.

The advantage of doing this is that the VM will not have to scan over lots
of anonymous pages (which we generally do not want to swap out), just to
find the page cache pages that it should evict.

This patch has the infrastructure and a basic policy to balance how much
we scan the anon lists and how much we scan the file lists.  The big
policy changes are in separate patches.

[lee.schermerhorn@hp.com: collect lru meminfo statistics from correct offset]
[kosaki.motohiro@jp.fujitsu.com: prevent incorrect oom under split_lru]
[kosaki.motohiro@jp.fujitsu.com: fix pagevec_move_tail() doesn't treat unevictable page]
[hugh@veritas.com: memcg swapbacked pages active]
[hugh@veritas.com: splitlru: BDI_CAP_SWAP_BACKED]
[akpm@linux-foundation.org: fix /proc/vmstat units]
[nishimura@mxp.nes.nec.co.jp: memcg: fix handling of shmem migration]
[kosaki.motohiro@jp.fujitsu.com: adjust Quicklists field of /proc/meminfo]
[kosaki.motohiro@jp.fujitsu.com: fix style issue of get_scan_ratio()]
Signed-off-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NLee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently we are defining explicit variables for the inactive and active
list.  An indexed array can be more generic and avoid repeating similar
code in several places in the reclaim code.

We are saving a few bytes in terms of code size:

Before:

   text    data     bss     dec     hex filename
4097753  573120 4092484 8763357  85b7dd vmlinux

After:

   text    data     bss     dec     hex filename
4097729  573120 4092484 8763333  85b7c5 vmlinux

Having an easy way to add new lru lists may ease future work on the
reclaim code.
Signed-off-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Ordinarily, memory holes in flatmem still have a valid memmap and is safe
to use. However, an architecture (ARM) frees up the memmap backing memory
holes on the assumption it is never used. /proc/pagetypeinfo reads the
whole range of pages in a zone believing that the memmap is valid and that
pfn_valid will return false if it is not. On ARM, freeing the memmap breaks
the page->zone linkages even though pfn_valid() returns true and the kernel
can oops shortly afterwards due to accessing a bogus struct zone *.

This patch lets architectures say when FLATMEM can have holes in the
memmap. Rather than an expensive check for valid memory, /proc/pagetypeinfo
will confirm that the page linkages are still valid by checking page->zone
is still the expected zone. The lookup of page_zone is safe as there is a
limited range of memory that is accessed when calling page_zone.  Even if
page_zone happens to return the correct zone, the impact is that the counters
in /proc/pagetypeinfo are slightly off but fragmentation monitoring is
unlikely to be relevant on an embedded system.
Reported-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NMel Gorman <mel@csn.ul.ie>
Tested-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch adds proper extern declarations for five variables in
include/linux/vmstat.h
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change references from for_each_cpu_mask to for_each_cpu_mask_nr
where appropriate
Reviewed-by: NPaul Jackson <pj@sgi.com>
Reviewed-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NMike Travis <travis@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

When accessing cpu_online_map, we should prevent dynamic changing
of cpu_online_map by get_online_cpus().

Unfortunately, all_vm_events() doesn't do that.
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: NChristoph Lameter <clameter@sgi.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fuse will use temporary buffers to write back dirty data from memory mappings
(normal writes are done synchronously).  This is needed, because there cannot
be any guarantee about the time in which a write will complete.

By using temporary buffers, from the MM's point if view the page is written
back immediately.  If the writeout was due to memory pressure, this
effectively migrates data from a full zone to a less full zone.

This patch adds a new counter (NR_WRITEBACK_TEMP) for the number of pages used
as temporary buffers.

[Lee.Schermerhorn@hp.com: add vmstat_text for NR_WRITEBACK_TEMP]
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

on memoryless node, /proc/pagetypeinfo is displayed slightly funny output.
this patch fix it.

output example (header is outputed, but no data is outputed)
--------------------------------------------------------------
Page block order: 14
Pages per block:  16384

Free pages count per migrate type at order       0      1      2      3      4      5    \
  6      7      8      9     10     11     12     13     14     15     16

Number of blocks type     Unmovable  Reclaimable      Movable      Reserve      Isolate
Page block order: 14
Pages per block:  16384

Free pages count per migrate type at order       0      1      2      3      4      5    \
  6      7      8      9     10     11     12     13     14     15     16
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: NMel Gorman <mel@csn.ul.ie>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We've found that it can take quite a bit of time (100's of usec) to get
through the zone loop in refresh_cpu_vm_stats().

Adding a cond_resched() to allow other threads to run in the non-preemptive
case.
Signed-off-by: NDimitri Sivanich <sivanich@sgi.com>
Acked-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Allocating huge pages directly from the buddy allocator is not guaranteed to
succeed.  Success depends on several factors (such as the amount of physical
memory available and the level of fragmentation).  With the addition of
dynamic hugetlb pool resizing, allocations can occur much more frequently.
For these reasons it is desirable to keep track of huge page allocation
successes and failures.

Add two new vmstat entries to track huge page allocations that succeed and
fail.  The presence of the two entries is contingent upon CONFIG_HUGETLB_PAGE
being enabled.

[akpm@linux-foundation.org: reduced ifdeffery]
Signed-off-by: NAdam Litke <agl@us.ibm.com>
Signed-off-by: NEric Munson <ebmunson@us.ibm.com>
Tested-by: NMel Gorman <mel@csn.ul.ie>
Reviewed-by: NAndy Whitcroft <apw@shadowen.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On NUMA, zone_statistics() is used to record events like numa hit, miss and
foreign.  It assumes that the first zone in a zonelist is the preferred zone.
When multiple zonelists are replaced by one that is filtered, this is no
longer the case.

This patch records what the preferred zone is rather than assuming the first
zone in the zonelist is it.  This simplifies the reading of later patches in
this set.
Signed-off-by: NMel Gorman <mel@csn.ul.ie>
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: NChristoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In a5d76b54 (memory unplug: page isolation by
KAMEZAWA Hiroyuki), "isolate" migratetype added.  but unfortunately, it
doesn't treat /proc/pagetypeinfo display logic.

this patch add "Isolate" to pagetype name field.

/proc/pagetype
before:
------------------------------------------------------------------------------------------------------------------------
Free pages count per migrate type at order       0      1      2      3      4      5      6      7      8      9     10
Node    0, zone      DMA, type    Unmovable      1      2      2      2      1      2      2      1      1      0      0
Node    0, zone      DMA, type  Reclaimable      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone      DMA, type      Movable      2      3      3      1      3      3      2      0      0      0      0
Node    0, zone      DMA, type      Reserve      0      0      0      0      0      0      0      0      0      0      1
Node    0, zone      DMA, type       <NULL>      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone   Normal, type    Unmovable      1      9      7      4      1      1      1      1      0      0      0
Node    0, zone   Normal, type  Reclaimable      5      2      0      0      1      1      0      0      0      1      0
Node    0, zone   Normal, type      Movable      0      1      1      0      0      0      1      0      0      1     60
Node    0, zone   Normal, type      Reserve      0      0      0      0      0      0      0      0      0      0      1
Node    0, zone   Normal, type       <NULL>      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone  HighMem, type    Unmovable      0      0      1      1      1      0      1      1      2      2      0
Node    0, zone  HighMem, type  Reclaimable      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone  HighMem, type      Movable    236     62      6      2      2      1      1      0      1      1     16
Node    0, zone  HighMem, type      Reserve      0      0      0      0      0      0      0      0      0      0      1
Node    0, zone  HighMem, type       <NULL>      0      0      0      0      0      0      0      0      0      0      0

Number of blocks type     Unmovable  Reclaimable      Movable      Reserve       <NULL>
Node 0, zone      DMA            1            0            2       1            0
Node 0, zone   Normal           10           40          169       1            0
Node 0, zone  HighMem            2            0          283       1            0

after:
------------------------------------------------------------------------------------------------------------------------
Free pages count per migrate type at order       0      1      2      3      4      5      6      7      8      9     10
Node    0, zone      DMA, type    Unmovable      1      2      2      2      1      2      2      1      1      0      0
Node    0, zone      DMA, type  Reclaimable      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone      DMA, type      Movable      2      3      3      1      3      3      2      0      0      0      0
Node    0, zone      DMA, type      Reserve      0      0      0      0      0      0      0      0      0      0      1
Node    0, zone      DMA, type      Isolate      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone   Normal, type    Unmovable      0      2      1      1      0      1      0      0      0      0      0
Node    0, zone   Normal, type  Reclaimable      1      1      1      1      1      0      1      1      1      0      0
Node    0, zone   Normal, type      Movable      0      1      1      1      0      1      0      1      0      0    196
Node    0, zone   Normal, type      Reserve      0      0      0      0      0      0      0      0      0      0      1
Node    0, zone   Normal, type      Isolate      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone  HighMem, type    Unmovable      0      1      0      0      0      1      1      1      2      2      0
Node    0, zone  HighMem, type  Reclaimable      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone  HighMem, type      Movable      1      0      1      1      0      0      0      0      1      0    200
Node    0, zone  HighMem, type      Reserve      0      0      0      0      0      0      0      0      0      0      1
Node    0, zone  HighMem, type      Isolate      0      0      0      0      0      0      0      0      0      0      0

Number of blocks type     Unmovable  Reclaimable      Movable      Reserve      Isolate
Node 0, zone      DMA            1            0            2       1            0
Node 0, zone   Normal            8            4          207       1            0
Node 0, zone  HighMem            2            0          283       1            0
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: NMel Gorman <mel@csn.ul.ie>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove the prefetch logic in order to avoid touching impossible per cpu
areas.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Cc: Mike Travis <travis@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We have repeatedly discussed if the cold pages still have a point. There is
one way to join the two lists: Use a single list and put the cold pages at the
end and the hot pages at the beginning. That way a single list can serve for
both types of allocations.

The discussion of the RFC for this and Mel's measurements indicate that
there may not be too much of a point left to having separate lists for
hot and cold pages (see http://marc.info/?t=119492914200001&r=1&w=2).
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Martin Bligh <mbligh@mbligh.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

1. Add comments explaining how the function can be called.

2. Collect global diffs in a local array and only spill
   them once into the global counters when the zone scan
   is finished. This means that we only touch each global
   counter once instead of each time we fold cpu counters
   into zone counters.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Mark start_cpu_timer() as __cpuinit instead of __devinit.
Fixes this section warning:

WARNING: vmlinux.o(.text+0x60e53): Section mismatch: reference to .init.text:start_cpu_timer (between 'vmstat_cpuup_callback' and 'vmstat_show')
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Acked-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Convert the int all_unreclaimable member of struct zone to unsigned long
flags.  This can now be used to specify several different zone flags such as
all_unreclaimable and reclaim_in_progress, which can now be removed and
converted to a per-zone flag.

Flags are set and cleared as follows:

	zone_set_flag(struct zone *zone, zone_flags_t flag)
	zone_clear_flag(struct zone *zone, zone_flags_t flag)

Defines the first zone flags, ZONE_ALL_UNRECLAIMABLE and ZONE_RECLAIM_LOCKED,
which have the same semantics as the old zone->all_unreclaimable and
zone->reclaim_in_progress, respectively.  Also converts all current users that
set or clear either flag to use the new interface.

Helper functions are defined to test the flags:

	int zone_is_all_unreclaimable(const struct zone *zone)
	int zone_is_reclaim_locked(const struct zone *zone)

All flag operators are of the atomic variety because there are currently
readers that are implemented that do not take zone->lock.

[akpm@linux-foundation.org: add needed include]
Cc: Andrea Arcangeli <andrea@suse.de>
Acked-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch contains the following cleanups:
- make the needlessly global setup_vmstat() static
- remove the unused refresh_vm_stats()
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Acked-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch provides fragmentation avoidance statistics via /proc/pagetypeinfo.
 The information is collected only on request so there is no runtime overhead.
 The statistics are in three parts:

The first part prints information on the size of blocks that pages are
being grouped on and looks like

Page block order: 10
Pages per block:  1024

The second part is a more detailed version of /proc/buddyinfo and looks like

Free pages count per migrate type at order       0      1      2      3      4      5      6      7      8      9     10
Node    0, zone      DMA, type    Unmovable      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone      DMA, type  Reclaimable      1      0      0      0      0      0      0      0      0      0      0
Node    0, zone      DMA, type      Movable      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone      DMA, type      Reserve      0      4      4      0      0      0      0      1      0      1      0
Node    0, zone   Normal, type    Unmovable    111      8      4      4      2      3      1      0      0      0      0
Node    0, zone   Normal, type  Reclaimable    293     89      8      0      0      0      0      0      0      0      0
Node    0, zone   Normal, type      Movable      1      6     13      9      7      6      3      0      0      0      0
Node    0, zone   Normal, type      Reserve      0      0      0      0      0      0      0      0      0      0      4

The third part looks like

Number of blocks type     Unmovable  Reclaimable      Movable      Reserve
Node 0, zone      DMA            0            1            2            1
Node 0, zone   Normal            3           17           94            4

To walk the zones within a node with interrupts disabled, walk_zones_in_node()
is introduced and shared between /proc/buddyinfo, /proc/zoneinfo and
/proc/pagetypeinfo to reduce code duplication.  It seems specific to what
vmstat.c requires but could be broken out as a general utility function in
mmzone.c if there were other other potential users.
Signed-off-by: NMel Gorman <mel@csn.ul.ie>
Acked-by: NAndy Whitcroft <apw@shadowen.org>
Acked-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove fs.h from mm.h. For this,
 1) Uninline vma_wants_writenotify(). It's pretty huge anyway.
 2) Add back fs.h or less bloated headers (err.h) to files that need it.

As result, on x86_64 allyesconfig, fs.h dependencies cut down from 3929 files
rebuilt down to 3444 (-12.3%).

Cross-compile tested without regressions on my two usual configs and (sigh):

alpha              arm-mx1ads        mips-bigsur          powerpc-ebony
alpha-allnoconfig  arm-neponset      mips-capcella        powerpc-g5
alpha-defconfig    arm-netwinder     mips-cobalt          powerpc-holly
alpha-up           arm-netx          mips-db1000          powerpc-iseries
arm                arm-ns9xxx        mips-db1100          powerpc-linkstation
arm-assabet        arm-omap_h2_1610  mips-db1200          powerpc-lite5200
arm-at91rm9200dk   arm-onearm        mips-db1500          powerpc-maple
arm-at91rm9200ek   arm-picotux200    mips-db1550          powerpc-mpc7448_hpc2
arm-at91sam9260ek  arm-pleb          mips-ddb5477         powerpc-mpc8272_ads
arm-at91sam9261ek  arm-pnx4008       mips-decstation      powerpc-mpc8313_rdb
arm-at91sam9263ek  arm-pxa255-idp    mips-e55             powerpc-mpc832x_mds
arm-at91sam9rlek   arm-realview      mips-emma2rh         powerpc-mpc832x_rdb
arm-ateb9200       arm-realview-smp  mips-excite          powerpc-mpc834x_itx
arm-badge4         arm-rpc           mips-fulong          powerpc-mpc834x_itxgp
arm-carmeva        arm-s3c2410       mips-ip22            powerpc-mpc834x_mds
arm-cerfcube       arm-shannon       mips-ip27            powerpc-mpc836x_mds
arm-clps7500       arm-shark         mips-ip32            powerpc-mpc8540_ads
arm-collie         arm-simpad        mips-jazz            powerpc-mpc8544_ds
arm-corgi          arm-spitz         mips-jmr3927         powerpc-mpc8560_ads
arm-csb337         arm-trizeps4      mips-malta           powerpc-mpc8568mds
arm-csb637         arm-versatile     mips-mipssim         powerpc-mpc85xx_cds
arm-ebsa110        i386              mips-mpc30x          powerpc-mpc8641_hpcn
arm-edb7211        i386-allnoconfig  mips-msp71xx         powerpc-mpc866_ads
arm-em_x270        i386-defconfig    mips-ocelot          powerpc-mpc885_ads
arm-ep93xx         i386-up           mips-pb1100          powerpc-pasemi
arm-footbridge     ia64              mips-pb1500          powerpc-pmac32
arm-fortunet       ia64-allnoconfig  mips-pb1550          powerpc-ppc64
arm-h3600          ia64-bigsur       mips-pnx8550-jbs     powerpc-prpmc2800
arm-h7201          ia64-defconfig    mips-pnx8550-stb810  powerpc-ps3
arm-h7202          ia64-gensparse    mips-qemu            powerpc-pseries
arm-hackkit        ia64-sim          mips-rbhma4200       powerpc-up
arm-integrator     ia64-sn2          mips-rbhma4500       s390
arm-iop13xx        ia64-tiger        mips-rm200           s390-allnoconfig
arm-iop32x         ia64-up           mips-sb1250-swarm    s390-defconfig
arm-iop33x         ia64-zx1          mips-sead            s390-up
arm-ixp2000        m68k              mips-tb0219          sparc
arm-ixp23xx        m68k-amiga        mips-tb0226          sparc-allnoconfig
arm-ixp4xx         m68k-apollo       mips-tb0287          sparc-defconfig
arm-jornada720     m68k-atari        mips-workpad         sparc-up
arm-kafa           m68k-bvme6000     mips-wrppmc          sparc64
arm-kb9202         m68k-hp300        mips-yosemite        sparc64-allnoconfig
arm-ks8695         m68k-mac          parisc               sparc64-defconfig
arm-lart           m68k-mvme147      parisc-allnoconfig   sparc64-up
arm-lpd270         m68k-mvme16x      parisc-defconfig     um-x86_64
arm-lpd7a400       m68k-q40          parisc-up            x86_64
arm-lpd7a404       m68k-sun3         powerpc              x86_64-allnoconfig
arm-lubbock        m68k-sun3x        powerpc-cell         x86_64-defconfig
arm-lusl7200       mips              powerpc-celleb       x86_64-up
arm-mainstone      mips-atlas        powerpc-chrp32
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The following 8 patches against 2.6.20-mm2 create a zone called ZONE_MOVABLE
that is only usable by allocations that specify both __GFP_HIGHMEM and
__GFP_MOVABLE.  This has the effect of keeping all non-movable pages within a
single memory partition while allowing movable allocations to be satisfied
from either partition.  The patches may be applied with the list-based
anti-fragmentation patches that groups pages together based on mobility.

The size of the zone is determined by a kernelcore= parameter specified at
boot-time.  This specifies how much memory is usable by non-movable
allocations and the remainder is used for ZONE_MOVABLE.  Any range of pages
within ZONE_MOVABLE can be released by migrating the pages or by reclaiming.

When selecting a zone to take pages from for ZONE_MOVABLE, there are two
things to consider.  First, only memory from the highest populated zone is
used for ZONE_MOVABLE.  On the x86, this is probably going to be ZONE_HIGHMEM
but it would be ZONE_DMA on ppc64 or possibly ZONE_DMA32 on x86_64.  Second,
the amount of memory usable by the kernel will be spread evenly throughout
NUMA nodes where possible.  If the nodes are not of equal size, the amount of
memory usable by the kernel on some nodes may be greater than others.

By default, the zone is not as useful for hugetlb allocations because they are
pinned and non-migratable (currently at least).  A sysctl is provided that
allows huge pages to be allocated from that zone.  This means that the huge
page pool can be resized to the size of ZONE_MOVABLE during the lifetime of
the system assuming that pages are not mlocked.  Despite huge pages being
non-movable, we do not introduce additional external fragmentation of note as
huge pages are always the largest contiguous block we care about.

Credit goes to Andy Whitcroft for catching a large variety of problems during
review of the patches.

This patch creates an additional zone, ZONE_MOVABLE.  This zone is only usable
by allocations which specify both __GFP_HIGHMEM and __GFP_MOVABLE.  Hot-added
memory continues to be placed in their existing destination as there is no
mechanism to redirect them to a specific zone.

[y-goto@jp.fujitsu.com: Fix section mismatch of memory hotplug related code]
[akpm@linux-foundation.org: various fixes]
Signed-off-by: NMel Gorman <mel@csn.ul.ie>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: NYasunori Goto <y-goto@jp.fujitsu.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Line up the vmstat_text with zone_stat_item

enum zone_stat_item {
	/* First 128 byte cacheline (assuming 64 bit words) */
	NR_FREE_PAGES,
	NR_INACTIVE,
	NR_ACTIVE,

We current have nr_active and nr_inactive reversed.

[ "OK with patch, though using initializers canbe handy to prevent such
   things in future:

	static const char * const vmstat_text[] = {
		[NR_FREE_PAGES] = "nr_free_pages",
		..."
							 - Alexey ]
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.

This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
   getting them indirectly

Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
   they don't need sched.h
b) sched.h stops being dependency for significant number of files:
   on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
   after patch it's only 3744 (-8.3%).

Cross-compile tested on

	all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
	alpha alpha-up
	arm
	i386 i386-up i386-defconfig i386-allnoconfig
	ia64 ia64-up
	m68k
	mips
	parisc parisc-up
	powerpc powerpc-up
	s390 s390-up
	sparc sparc-up
	sparc64 sparc64-up
	um-x86_64
	x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig

as well as my two usual configs.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

VM statistics updates do not matter if the kernel is in idle powersaving
mode.  So allow the timer to be deferred.

It would be better though if we could switch the timer between deferrable
and nondeferrable based on differentials present.  The timer would start
out nondeferrable and if we find that there were no updates in the last
statistics interval then we would switch the timer to deferrable.  If the
timer later finds again that there are differentials then go to
nondeferrable again.

And yet another way would be to run the timer shortly before going to idle?

The solution here means that the VM counters may be slightly off during
idle since differentials may be still pending while the timer is deferred.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently the slab allocators contain callbacks into the page allocator to
perform the draining of pagesets on remote nodes.  This requires SLUB to have
a whole subsystem in order to be compatible with SLAB.  Moving node draining
out of the slab allocators avoids a section of code in SLUB.

Move the node draining so that is is done when the vm statistics are updated.
At that point we are already touching all the cachelines with the pagesets of
a processor.

Add a expire counter there.  If we have to update per zone or global vm
statistics then assume that the pageset will require subsequent draining.

The expire counter will be decremented on each vm stats update pass until it
reaches zero.  Then we will drain one batch from the pageset.  The draining
will cause vm counter updates which will then cause another expiration until
the pcp is empty.  So we will drain a batch every 3 seconds.

Note that remote node draining is a somewhat esoteric feature that is required
on large NUMA systems because otherwise significant portions of system memory
can become trapped in pcp queues.  The number of pcp is determined by the
number of processors and nodes in a system.  A system with 4 processors and 2
nodes has 8 pcps which is okay.  But a system with 1024 processors and 512
nodes has 512k pcps with a high potential for large amount of memory being
caught in them.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make it configurable.  Code in mm makes the vm statistics intervals
independent from the cache reaper use that opportunity to make it
configurable.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

vmstat is currently using the cache reaper to periodically bring the
statistics up to date.  The cache reaper does only exists in SLUB as a way to
provide compatibility with SLAB.  This patch removes the vmstat calls from the
slab allocators and provides its own handling.

The advantage is also that we can use a different frequency for the updates.
Refreshing vm stats is a pretty fast job so we can run this every second and
stagger this by only one tick.  This will lead to some overlap in large
systems.  F.e a system running at 250 HZ with 1024 processors will have 4 vm
updates occurring at once.

However, the vm stats update only accesses per node information.  It is only
necessary to stagger the vm statistics updates per processor in each node.  Vm
counter updates occurring on distant nodes will not cause cacheline
contention.

We could implement an alternate approach that runs the first processor on each
node at the second and then each of the other processor on a node on a
subsequent tick.  That may be useful to keep a large amount of the second free
of timer activity.  Maybe the timer folks will have some feedback on this one?

[jirislaby@gmail.com: add missing break]
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress.  This
patch introduces such notifications and causes them to be used during
suspend and resume transitions.  It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).

[oleg@tv-sign.ru: cleanups]
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make ZONE_DMA optional in core code.

- ifdef all code for ZONE_DMA and related definitions following the example
  for ZONE_DMA32 and ZONE_HIGHMEM.

- Without ZONE_DMA, ZONE_HIGHMEM and ZONE_DMA32 we get to a ZONES_SHIFT of
  0.

- Modify the VM statistics to work correctly without a DMA zone.

- Modify slab to not create DMA slabs if there is no ZONE_DMA.

[akpm@osdl.org: cleanup]
[jdike@addtoit.com: build fix]
[apw@shadowen.org: Simplify calculation of the number of bits we need for ZONES_SHIFT]
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: NAndy Whitcroft <apw@shadowen.org>
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>