Commit Graph

535 Commits

Author SHA1 Message Date
Mel Gorman
9ee493ce0a mm: page allocator: drain per-cpu lists after direct reclaim allocation fails
When under significant memory pressure, a process enters direct reclaim
and immediately afterwards tries to allocate a page.  If it fails and no
further progress is made, it's possible the system will go OOM.  However,
on systems with large amounts of memory, it's possible that a significant
number of pages are on per-cpu lists and inaccessible to the calling
process.  This leads to a process entering direct reclaim more often than
it should increasing the pressure on the system and compounding the
problem.

This patch notes that if direct reclaim is making progress but allocations
are still failing that the system is already under heavy pressure.  In
this case, it drains the per-cpu lists and tries the allocation a second
time before continuing.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09 18:57:25 -07:00
Christoph Lameter
aa45484031 mm: page allocator: calculate a better estimate of NR_FREE_PAGES when memory is low and kswapd is awake
Ordinarily watermark checks are based on the vmstat NR_FREE_PAGES as it is
cheaper than scanning a number of lists.  To avoid synchronization
overhead, counter deltas are maintained on a per-cpu basis and drained
both periodically and when the delta is above a threshold.  On large CPU
systems, the difference between the estimated and real value of
NR_FREE_PAGES can be very high.  If NR_FREE_PAGES is much higher than
number of real free page in buddy, the VM can allocate pages below min
watermark, at worst reducing the real number of pages to zero.  Even if
the OOM killer kills some victim for freeing memory, it may not free
memory if the exit path requires a new page resulting in livelock.

This patch introduces a zone_page_state_snapshot() function (courtesy of
Christoph) that takes a slightly more accurate view of an arbitrary vmstat
counter.  It is used to read NR_FREE_PAGES while kswapd is awake to avoid
the watermark being accidentally broken.  The estimate is not perfect and
may result in cache line bounces but is expected to be lighter than the
IPI calls necessary to continually drain the per-cpu counters while kswapd
is awake.

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09 18:57:25 -07:00
Mel Gorman
72853e2991 mm: page allocator: update free page counters after pages are placed on the free list
When allocating a page, the system uses NR_FREE_PAGES counters to
determine if watermarks would remain intact after the allocation was made.
This check is made without interrupts disabled or the zone lock held and
so is race-prone by nature.  Unfortunately, when pages are being freed in
batch, the counters are updated before the pages are added on the list.
During this window, the counters are misleading as the pages do not exist
yet.  When under significant pressure on systems with large numbers of
CPUs, it's possible for processes to make progress even though they should
have been stalled.  This is particularly problematic if a number of the
processes are using GFP_ATOMIC as the min watermark can be accidentally
breached and in extreme cases, the system can livelock.

This patch updates the counters after the pages have been added to the
list.  This makes the allocator more cautious with respect to preserving
the watermarks and mitigates livelock possibilities.

[akpm@linux-foundation.org: avoid modifying incoming args]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09 18:57:25 -07:00
KOSAKI Motohiro
25edde0332 vmscan: kill prev_priority completely
Since 2.6.28 zone->prev_priority is unused. Then it can be removed
safely. It reduce stack usage slightly.

Now I have to say that I'm sorry. 2 years ago, I thought prev_priority
can be integrate again, it's useful. but four (or more) times trying
haven't got good performance number. Thus I give up such approach.

The rest of this changelog is notes on prev_priority and why it existed in
the first place and why it might be not necessary any more. This information
is based heavily on discussions between Andrew Morton, Rik van Riel and
Kosaki Motohiro who is heavily quotes from.

Historically prev_priority was important because it determined when the VM
would start unmapping PTE pages. i.e. there are no balances of note within
the VM, Anon vs File and Mapped vs Unmapped. Without prev_priority, there
is a potential risk of unnecessarily increasing minor faults as a large
amount of read activity of use-once pages could push mapped pages to the
end of the LRU and get unmapped.

There is no proof this is still a problem but currently it is not considered
to be. Active files are not deactivated if the active file list is smaller
than the inactive list reducing the liklihood that file-mapped pages are
being pushed off the LRU and referenced executable pages are kept on the
active list to avoid them getting pushed out by read activity.

Even if it is a problem, prev_priority prev_priority wouldn't works
nowadays. First of all, current vmscan still a lot of UP centric code. it
expose some weakness on some dozens CPUs machine. I think we need more and
more improvement.

The problem is, current vmscan mix up per-system-pressure, per-zone-pressure
and per-task-pressure a bit. example, prev_priority try to boost priority to
other concurrent priority. but if the another task have mempolicy restriction,
it is unnecessary, but also makes wrong big latency and exceeding reclaim.
per-task based priority + prev_priority adjustment make the emulation of
per-system pressure. but it have two issue 1) too rough and brutal emulation
2) we need per-zone pressure, not per-system.

Another example, currently DEF_PRIORITY is 12. it mean the lru rotate about
2 cycle (1/4096 + 1/2048 + 1/1024 + .. + 1) before invoking OOM-Killer.
but if 10,0000 thrreads enter DEF_PRIORITY reclaim at the same time, the
system have higher memory pressure than priority==0 (1/4096*10,000 > 2).
prev_priority can't solve such multithreads workload issue. In other word,
prev_priority concept assume the sysmtem don't have lots threads."

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michael Rubin <mrubin@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:45:00 -07:00
Minchan Kim
ff321feac2 mm: rename try_set_zone_oom() to try_set_zonelist_oom()
We have been used naming try_set_zone_oom and clear_zonelist_oom.
The role of functions is to lock of zonelist for preventing parallel
OOM. So clear_zonelist_oom makes sense but try_set_zone_oome is rather
awkward and unmatched with clear_zonelist_oom.

Let's change it with try_set_zonelist_oom.

Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:44:57 -07:00
David Rientjes
03668b3ceb oom: avoid oom killer for lowmem allocations
If memory has been depleted in lowmem zones even with the protection
afforded to it by /proc/sys/vm/lowmem_reserve_ratio, it is unlikely that
killing current users will help.  The memory is either reclaimable (or
migratable) already, in which case we should not invoke the oom killer at
all, or it is pinned by an application for I/O.  Killing such an
application may leave the hardware in an unspecified state and there is no
guarantee that it will be able to make a timely exit.

Lowmem allocations are now failed in oom conditions when __GFP_NOFAIL is
not used so that the task can perhaps recover or try again later.

Previously, the heuristic provided some protection for those tasks with
CAP_SYS_RAWIO, but this is no longer necessary since we will not be
killing tasks for the purposes of ISA allocations.

high_zoneidx is gfp_zone(gfp_flags), meaning that ZONE_NORMAL will be the
default for all allocations that are not __GFP_DMA, __GFP_DMA32,
__GFP_HIGHMEM, and __GFP_MOVABLE on kernels configured to support those
flags.  Testing for high_zoneidx being less than ZONE_NORMAL will only
return true for allocations that have either __GFP_DMA or __GFP_DMA32.

Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:44:56 -07:00
Yinghai Lu
b8ab9f8202 x86,nobootmem: make alloc_bootmem_node fall back to other node when 32bit numa is used
Borislav Petkov reported his 32bit numa system has problem:

[    0.000000] Reserving total of 4c00 pages for numa KVA remap
[    0.000000] kva_start_pfn ~ 32800 max_low_pfn ~ 375fe
[    0.000000] max_pfn = 238000
[    0.000000] 8202MB HIGHMEM available.
[    0.000000] 885MB LOWMEM available.
[    0.000000]   mapped low ram: 0 - 375fe000
[    0.000000]   low ram: 0 - 375fe000
[    0.000000] alloc (nid=8 100000 - 7ee00000) (1000000 - ffffffff) 1000 1000 => 34e7000
[    0.000000] alloc (nid=8 100000 - 7ee00000) (1000000 - ffffffff) 200 40 => 34c9d80
[    0.000000] alloc (nid=0 100000 - 7ee00000) (1000000 - ffffffffffffffff) 180 40 => 34e6140
[    0.000000] alloc (nid=1 80000000 - c7e60000) (1000000 - ffffffffffffffff) 240 40 => 80000000
[    0.000000] BUG: unable to handle kernel paging request at 40000000
[    0.000000] IP: [<c2c8cff1>] __alloc_memory_core_early+0x147/0x1d6
[    0.000000] *pdpt = 0000000000000000 *pde = f000ff53f000ff00
...
[    0.000000] Call Trace:
[    0.000000]  [<c2c8b4f8>] ? __alloc_bootmem_node+0x216/0x22f
[    0.000000]  [<c2c90c9b>] ? sparse_early_usemaps_alloc_node+0x5a/0x10b
[    0.000000]  [<c2c9149e>] ? sparse_init+0x1dc/0x499
[    0.000000]  [<c2c79118>] ? paging_init+0x168/0x1df
[    0.000000]  [<c2c780ff>] ? native_pagetable_setup_start+0xef/0x1bb

looks like it allocates too much high address for bootmem.

Try to cut limit with get_max_mapped()

Reported-by: Borislav Petkov <borislav.petkov@amd.com>
Tested-by: Conny Seidel <conny.seidel@amd.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@kernel.org>		[2.6.34.x]
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-20 16:25:40 -07:00
Catalin Marinas
9078370c0d kmemleak: Add support for NO_BOOTMEM configurations
With commits 08677214 and 59be5a8e, alloc_bootmem()/free_bootmem() and
friends use the early_res functions for memory management when
NO_BOOTMEM is enabled. This patch adds the kmemleak calls in the
corresponding code paths for bootmem allocations.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: stable@kernel.org
2010-07-19 11:54:15 +01:00
Lee Schermerhorn
7aac789885 numa: introduce numa_mem_id()- effective local memory node id
Introduce numa_mem_id(), based on generic percpu variable infrastructure
to track "nearest node with memory" for archs that support memoryless
nodes.

Define API in <linux/topology.h> when CONFIG_HAVE_MEMORYLESS_NODES
defined, else stubs.  Architectures will define HAVE_MEMORYLESS_NODES
if/when they support them.

Archs can override definitions of:

numa_mem_id() - returns node number of "local memory" node
set_numa_mem() - initialize [this cpus'] per cpu variable 'numa_mem'
cpu_to_mem()  - return numa_mem for specified cpu; may be used as lvalue

Generic initialization of 'numa_mem' occurs in __build_all_zonelists().
This will initialize the boot cpu at boot time, and all cpus on change of
numa_zonelist_order, or when node or memory hot-plug requires zonelist
rebuild.  Archs that support memoryless nodes will need to initialize
'numa_mem' for secondary cpus as they're brought on-line.

[akpm@linux-foundation.org: fix build]
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
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: <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
Lee Schermerhorn
7281201922 numa: add generic percpu var numa_node_id() implementation
Rework the generic version of the numa_node_id() function to use the new
generic percpu variable infrastructure.

Guard the new implementation with a new config option:

        CONFIG_USE_PERCPU_NUMA_NODE_ID.

Archs which support this new implemention will default this option to 'y'
when NUMA is configured.  This config option could be removed if/when all
archs switch over to the generic percpu implementation of numa_node_id().
Arch support involves:

  1) converting any existing per cpu variable implementations to use
     this implementation.  x86_64 is an instance of such an arch.
  2) archs that don't use a per cpu variable for numa_node_id() will
     need to initialize the new per cpu variable "numa_node" as cpus
     are brought on-line.  ia64 is an example.
  3) Defining USE_PERCPU_NUMA_NODE_ID in arch dependent Kconfig--e.g.,
     when NUMA is configured.  This is required because I have
     retained the old implementation by default to allow archs to
     be modified incrementally, as desired.

Subsequent patches will convert x86_64 and ia64 to use this implemenation.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: 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: <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
Haicheng Li
4eaf3f6439 mem-hotplug: fix potential race while building zonelist for new populated zone
Add global mutex zonelists_mutex to fix the possible race:

     CPU0                                  CPU1                    CPU2
(1) zone->present_pages += online_pages;
(2)                                       build_all_zonelists();
(3)                                                               alloc_page();
(4)                                                               free_page();
(5) build_all_zonelists();
(6)   __build_all_zonelists();
(7)     zone->pageset = alloc_percpu();

In step (3,4), zone->pageset still points to boot_pageset, so bad
things may happen if 2+ nodes are in this state. Even if only 1 node
is accessing the boot_pageset, (3) may still consume too much memory
to fail the memory allocations in step (7).

Besides, atomic operation ensures alloc_percpu() in step (7) will never fail
since there is a new fresh memory block added in step(6).

[haicheng.li@linux.intel.com: hold zonelists_mutex when build_all_zonelists]
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: Andi Kleen <andi.kleen@intel.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:02 -07:00
Haicheng Li
1f522509c7 mem-hotplug: avoid multiple zones sharing same boot strapping boot_pageset
For each new populated zone of hotadded node, need to update its pagesets
with dynamically allocated per_cpu_pageset struct for all possible CPUs:

    1) Detach zone->pageset from the shared boot_pageset
       at end of __build_all_zonelists().

    2) Use mutex to protect zone->pageset when it's still
       shared in onlined_pages()

Otherwises, multiple zones of different nodes would share same boot strapping
boot_pageset for same CPU, which will finally cause below kernel panic:

  ------------[ cut here ]------------
  kernel BUG at mm/page_alloc.c:1239!
  invalid opcode: 0000 [#1] SMP
  ...
  Call Trace:
   [<ffffffff811300c1>] __alloc_pages_nodemask+0x131/0x7b0
   [<ffffffff81162e67>] alloc_pages_current+0x87/0xd0
   [<ffffffff81128407>] __page_cache_alloc+0x67/0x70
   [<ffffffff811325f0>] __do_page_cache_readahead+0x120/0x260
   [<ffffffff81132751>] ra_submit+0x21/0x30
   [<ffffffff811329c6>] ondemand_readahead+0x166/0x2c0
   [<ffffffff81132ba0>] page_cache_async_readahead+0x80/0xa0
   [<ffffffff8112a0e4>] generic_file_aio_read+0x364/0x670
   [<ffffffff81266cfa>] nfs_file_read+0xca/0x130
   [<ffffffff8117b20a>] do_sync_read+0xfa/0x140
   [<ffffffff8117bf75>] vfs_read+0xb5/0x1a0
   [<ffffffff8117c151>] sys_read+0x51/0x80
   [<ffffffff8103c032>] system_call_fastpath+0x16/0x1b
  RIP  [<ffffffff8112ff13>] get_page_from_freelist+0x883/0x900
   RSP <ffff88000d1e78a8>
  ---[ end trace 4bda28328b9990db ]

[akpm@linux-foundation.org: merge fix]
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: Andi Kleen <andi.kleen@intel.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:01 -07:00
Wu Fengguang
319774e25f mem-hotplug: separate setup_per_cpu_pageset() into separate functions
No behavior change here.

Move some of setup_per_cpu_pageset() code into a new function
setup_zone_pageset() that will be useful for memory hotplug.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Reviewed-by: Andi Kleen <andi.kleen@intel.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:01 -07:00
KOSAKI Motohiro
ec95f53aa6 mm: introduce free_pages_prepare()
free_hot_cold_page() and __free_pages_ok() have very similar freeing
preparation.  Consolidate them.

[akpm@linux-foundation.org: fix busted coding style]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:00 -07:00
Mel Gorman
4f92e2586b mm: compaction: defer compaction using an exponential backoff when compaction fails
The fragmentation index may indicate that a failure is due to external
fragmentation but after a compaction run completes, it is still possible
for an allocation to fail.  There are two obvious reasons as to why

  o Page migration cannot move all pages so fragmentation remains
  o A suitable page may exist but watermarks are not met

In the event of compaction followed by an allocation failure, this patch
defers further compaction in the zone (1 << compact_defer_shift) times.
If the next compaction attempt also fails, compact_defer_shift is
increased up to a maximum of 6.  If compaction succeeds, the defer
counters are reset again.

The zone that is deferred is the first zone in the zonelist - i.e.  the
preferred zone.  To defer compaction in the other zones, the information
would need to be stored in the zonelist or implemented similar to the
zonelist_cache.  This would impact the fast-paths and is not justified at
this time.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:00 -07:00
Mel Gorman
56de7263fc mm: compaction: direct compact when a high-order allocation fails
Ordinarily when a high-order allocation fails, direct reclaim is entered
to free pages to satisfy the allocation.  With this patch, it is
determined if an allocation failed due to external fragmentation instead
of low memory and if so, the calling process will compact until a suitable
page is freed.  Compaction by moving pages in memory is considerably
cheaper than paging out to disk and works where there are locked pages or
no swap.  If compaction fails to free a page of a suitable size, then
reclaim will still occur.

Direct compaction returns as soon as possible.  As each block is
compacted, it is checked if a suitable page has been freed and if so, it
returns.

[akpm@linux-foundation.org: Fix build errors]
[aarcange@redhat.com: fix count_vm_event preempt in memory compaction direct reclaim]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
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>
2010-05-25 08:06:59 -07:00
Mel Gorman
748446bb6b mm: compaction: memory compaction core
This patch is the core of a mechanism which compacts memory in a zone by
relocating movable pages towards the end of the zone.

A single compaction run involves a migration scanner and a free scanner.
Both scanners operate on pageblock-sized areas in the zone.  The migration
scanner starts at the bottom of the zone and searches for all movable
pages within each area, isolating them onto a private list called
migratelist.  The free scanner starts at the top of the zone and searches
for suitable areas and consumes the free pages within making them
available for the migration scanner.  The pages isolated for migration are
then migrated to the newly isolated free pages.

[aarcange@redhat.com: Fix unsafe optimisation]
[mel@csn.ul.ie: do not schedule work on other CPUs for compaction]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:06:59 -07:00
David Rientjes
e325c90ffc mm: default to node zonelist ordering when nodes have only lowmem
There are two types of zonelist ordering methodologies:

 - node order, preferring allocations on a node to stay local to and

 - zone order, preferring allocations come from a higher zone to avoid
   allocating in lowmem zones even though they may not be local.

The ordering technique used by the kernel is configurable on the command
line, but also has some logic to determine what the default should be.

This logic currently lacks knowledge of systems where a node may only have
lowmem.  For such systems, it is necessary to use node order so that
GFP_KERNEL allocations may be satisfied by nodes consisting of only
lowmem.

If zone order is used, GFP_KERNEL allocations to such nodes are actually
allocated on a node with local affinity that includes ZONE_NORMAL.

This change defaults to node zonelist ordering if any node lacks
ZONE_NORMAL.

To force zone order, append 'numa_zonelist_order=zone' to the kernel
command line.

Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:06:58 -07:00
Miao Xie
c0ff7453bb cpuset,mm: fix no node to alloc memory when changing cpuset's mems
Before applying this patch, cpuset updates task->mems_allowed and
mempolicy by setting all new bits in the nodemask first, and clearing all
old unallowed bits later.  But in the way, the allocator may find that
there is no node to alloc memory.

The reason is that cpuset rebinds the task's mempolicy, it cleans the
nodes which the allocater can alloc pages on, for example:

(mpol: mempolicy)
	task1			task1's mpol	task2
	alloc page		1
	  alloc on node0? NO	1
				1		change mems from 1 to 0
				1		rebind task1's mpol
				0-1		  set new bits
				0	  	  clear disallowed bits
	  alloc on node1? NO	0
	  ...
	can't alloc page
	  goto oom

This patch fixes this problem by expanding the nodes range first(set newly
allowed bits) and shrink it lazily(clear newly disallowed bits).  So we
use a variable to tell the write-side task that read-side task is reading
nodemask, and the write-side task clears newly disallowed nodes after
read-side task ends the current memory allocation.

[akpm@linux-foundation.org: fix spello]
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Paul Menage <menage@google.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:06:57 -07:00
Corrado Zoccolo
6dda9d55bf page allocator: reduce fragmentation in buddy allocator by adding buddies that are merging to the tail of the free lists
In order to reduce fragmentation, this patch classifies freed pages in two
groups according to their probability of being part of a high order merge.
 Pages belonging to a compound whose next-highest buddy is free are more
likely to be part of a high order merge in the near future, so they will
be added at the tail of the freelist.  The remaining pages are put at the
front of the freelist.

In this way, the pages that are more likely to cause a big merge are kept
free longer.  Consequently there is a tendency to aggregate the
long-living allocations on a subset of the compounds, reducing the
fragmentation.

This heuristic was tested on three machines, x86, x86-64 and ppc64 with
3GB of RAM in each machine.  The tests were kernbench, netperf, sysbench
and STREAM for performance and a high-order stress test for huge page
allocations.

KernBench X86
Elapsed mean     374.77 ( 0.00%)   375.10 (-0.09%)
User    mean     649.53 ( 0.00%)   650.44 (-0.14%)
System  mean      54.75 ( 0.00%)    54.18 ( 1.05%)
CPU     mean     187.75 ( 0.00%)   187.25 ( 0.27%)

KernBench X86-64
Elapsed mean      94.45 ( 0.00%)    94.01 ( 0.47%)
User    mean     323.27 ( 0.00%)   322.66 ( 0.19%)
System  mean      36.71 ( 0.00%)    36.50 ( 0.57%)
CPU     mean     380.75 ( 0.00%)   381.75 (-0.26%)

KernBench PPC64
Elapsed mean     173.45 ( 0.00%)   173.74 (-0.17%)
User    mean     587.99 ( 0.00%)   587.95 ( 0.01%)
System  mean      60.60 ( 0.00%)    60.57 ( 0.05%)
CPU     mean     373.50 ( 0.00%)   372.75 ( 0.20%)

Nothing notable for kernbench.

NetPerf UDP X86
      64    42.68 ( 0.00%)     42.77 ( 0.21%)
     128    85.62 ( 0.00%)     85.32 (-0.35%)
     256   170.01 ( 0.00%)    168.76 (-0.74%)
    1024   655.68 ( 0.00%)    652.33 (-0.51%)
    2048  1262.39 ( 0.00%)   1248.61 (-1.10%)
    3312  1958.41 ( 0.00%)   1944.61 (-0.71%)
    4096  2345.63 ( 0.00%)   2318.83 (-1.16%)
    8192  4132.90 ( 0.00%)   4089.50 (-1.06%)
   16384  6770.88 ( 0.00%)   6642.05 (-1.94%)*

NetPerf UDP X86-64
      64   148.82 ( 0.00%)    154.92 ( 3.94%)
     128   298.96 ( 0.00%)    312.95 ( 4.47%)
     256   583.67 ( 0.00%)    626.39 ( 6.82%)
    1024  2293.18 ( 0.00%)   2371.10 ( 3.29%)
    2048  4274.16 ( 0.00%)   4396.83 ( 2.79%)
    3312  6356.94 ( 0.00%)   6571.35 ( 3.26%)
    4096  7422.68 ( 0.00%)   7635.42 ( 2.79%)*
    8192 12114.81 ( 0.00%)* 12346.88 ( 1.88%)
   16384 17022.28 ( 0.00%)* 17033.19 ( 0.06%)*
             1.64%             2.73%

NetPerf UDP PPC64
      64    49.98 ( 0.00%)     50.25 ( 0.54%)
     128    98.66 ( 0.00%)    100.95 ( 2.27%)
     256   197.33 ( 0.00%)    191.03 (-3.30%)
    1024   761.98 ( 0.00%)    785.07 ( 2.94%)
    2048  1493.50 ( 0.00%)   1510.85 ( 1.15%)
    3312  2303.95 ( 0.00%)   2271.72 (-1.42%)
    4096  2774.56 ( 0.00%)   2773.06 (-0.05%)
    8192  4918.31 ( 0.00%)   4793.59 (-2.60%)
   16384  7497.98 ( 0.00%)   7749.52 ( 3.25%)

The tests are run to have confidence limits within 1%.  Results marked
with a * were not confident although in this case, it's only outside by
small amounts.  Even with some results that were not confident, the
netperf UDP results were generally positive.

NetPerf TCP X86
      64   652.25 ( 0.00%)*   648.12 (-0.64%)*
            23.80%            22.82%
     128  1229.98 ( 0.00%)*  1220.56 (-0.77%)*
            21.03%            18.90%
     256  2105.88 ( 0.00%)   1872.03 (-12.49%)*
             1.00%            16.46%
    1024  3476.46 ( 0.00%)*  3548.28 ( 2.02%)*
            13.37%            11.39%
    2048  4023.44 ( 0.00%)*  4231.45 ( 4.92%)*
             9.76%            12.48%
    3312  4348.88 ( 0.00%)*  4396.96 ( 1.09%)*
             6.49%             8.75%
    4096  4726.56 ( 0.00%)*  4877.71 ( 3.10%)*
             9.85%             8.50%
    8192  4732.28 ( 0.00%)*  5777.77 (18.10%)*
             9.13%            13.04%
   16384  5543.05 ( 0.00%)*  5906.24 ( 6.15%)*
             7.73%             8.68%

NETPERF TCP X86-64
            netperf-tcp-vanilla-netperf       netperf-tcp
                   tcp-vanilla     pgalloc-delay
      64  1895.87 ( 0.00%)*  1775.07 (-6.81%)*
             5.79%             4.78%
     128  3571.03 ( 0.00%)*  3342.20 (-6.85%)*
             3.68%             6.06%
     256  5097.21 ( 0.00%)*  4859.43 (-4.89%)*
             3.02%             2.10%
    1024  8919.10 ( 0.00%)*  8892.49 (-0.30%)*
             5.89%             6.55%
    2048 10255.46 ( 0.00%)* 10449.39 ( 1.86%)*
             7.08%             7.44%
    3312 10839.90 ( 0.00%)* 10740.15 (-0.93%)*
             6.87%             7.33%
    4096 10814.84 ( 0.00%)* 10766.97 (-0.44%)*
             6.86%             8.18%
    8192 11606.89 ( 0.00%)* 11189.28 (-3.73%)*
             7.49%             5.55%
   16384 12554.88 ( 0.00%)* 12361.22 (-1.57%)*
             7.36%             6.49%

NETPERF TCP PPC64
            netperf-tcp-vanilla-netperf       netperf-tcp
                   tcp-vanilla     pgalloc-delay
      64   594.17 ( 0.00%)    596.04 ( 0.31%)*
             1.00%             2.29%
     128  1064.87 ( 0.00%)*  1074.77 ( 0.92%)*
             1.30%             1.40%
     256  1852.46 ( 0.00%)*  1856.95 ( 0.24%)
             1.25%             1.00%
    1024  3839.46 ( 0.00%)*  3813.05 (-0.69%)
             1.02%             1.00%
    2048  4885.04 ( 0.00%)*  4881.97 (-0.06%)*
             1.15%             1.04%
    3312  5506.90 ( 0.00%)   5459.72 (-0.86%)
    4096  6449.19 ( 0.00%)   6345.46 (-1.63%)
    8192  7501.17 ( 0.00%)   7508.79 ( 0.10%)
   16384  9618.65 ( 0.00%)   9490.10 (-1.35%)

There was a distinct lack of confidence in the X86* figures so I included
what the devation was where the results were not confident.  Many of the
results, whether gains or losses were within the standard deviation so no
solid conclusion can be reached on performance impact.  Looking at the
figures, only the X86-64 ones look suspicious with a few losses that were
outside the noise.  However, the results were so unstable that without
knowing why they vary so much, a solid conclusion cannot be reached.

SYSBENCH X86
              sysbench-vanilla     pgalloc-delay
           1  7722.85 ( 0.00%)  7756.79 ( 0.44%)
           2 14901.11 ( 0.00%) 13683.44 (-8.90%)
           3 15171.71 ( 0.00%) 14888.25 (-1.90%)
           4 14966.98 ( 0.00%) 15029.67 ( 0.42%)
           5 14370.47 ( 0.00%) 14865.00 ( 3.33%)
           6 14870.33 ( 0.00%) 14845.57 (-0.17%)
           7 14429.45 ( 0.00%) 14520.85 ( 0.63%)
           8 14354.35 ( 0.00%) 14362.31 ( 0.06%)

SYSBENCH X86-64
           1 17448.70 ( 0.00%) 17484.41 ( 0.20%)
           2 34276.39 ( 0.00%) 34251.00 (-0.07%)
           3 50805.25 ( 0.00%) 50854.80 ( 0.10%)
           4 66667.10 ( 0.00%) 66174.69 (-0.74%)
           5 66003.91 ( 0.00%) 65685.25 (-0.49%)
           6 64981.90 ( 0.00%) 65125.60 ( 0.22%)
           7 64933.16 ( 0.00%) 64379.23 (-0.86%)
           8 63353.30 ( 0.00%) 63281.22 (-0.11%)
           9 63511.84 ( 0.00%) 63570.37 ( 0.09%)
          10 62708.27 ( 0.00%) 63166.25 ( 0.73%)
          11 62092.81 ( 0.00%) 61787.75 (-0.49%)
          12 61330.11 ( 0.00%) 61036.34 (-0.48%)
          13 61438.37 ( 0.00%) 61994.47 ( 0.90%)
          14 62304.48 ( 0.00%) 62064.90 (-0.39%)
          15 63296.48 ( 0.00%) 62875.16 (-0.67%)
          16 63951.76 ( 0.00%) 63769.09 (-0.29%)

SYSBENCH PPC64
                             -sysbench-pgalloc-delay-sysbench
              sysbench-vanilla     pgalloc-delay
           1  7645.08 ( 0.00%)  7467.43 (-2.38%)
           2 14856.67 ( 0.00%) 14558.73 (-2.05%)
           3 21952.31 ( 0.00%) 21683.64 (-1.24%)
           4 27946.09 ( 0.00%) 28623.29 ( 2.37%)
           5 28045.11 ( 0.00%) 28143.69 ( 0.35%)
           6 27477.10 ( 0.00%) 27337.45 (-0.51%)
           7 26489.17 ( 0.00%) 26590.06 ( 0.38%)
           8 26642.91 ( 0.00%) 25274.33 (-5.41%)
           9 25137.27 ( 0.00%) 24810.06 (-1.32%)
          10 24451.99 ( 0.00%) 24275.85 (-0.73%)
          11 23262.20 ( 0.00%) 23674.88 ( 1.74%)
          12 24234.81 ( 0.00%) 23640.89 (-2.51%)
          13 24577.75 ( 0.00%) 24433.50 (-0.59%)
          14 25640.19 ( 0.00%) 25116.52 (-2.08%)
          15 26188.84 ( 0.00%) 26181.36 (-0.03%)
          16 26782.37 ( 0.00%) 26255.99 (-2.00%)

Again, there is little to conclude here.  While there are a few losses,
the results vary by +/- 8% in some cases.  They are the results of most
concern as there are some large losses but it's also within the variance
typically seen between kernel releases.

The STREAM results varied so little and are so verbose that I didn't
include them here.

The final test stressed how many huge pages can be allocated.  The
absolute number of huge pages allocated are the same with or without the
page.  However, the "unusability free space index" which is a measure of
external fragmentation was slightly lower (lower is better) throughout the
lifetime of the system.  I also measured the latency of how long it took
to successfully allocate a huge page.  The latency was slightly lower and
on X86 and PPC64, more huge pages were allocated almost immediately from
the free lists.  The improvement is slight but there.

[mel@csn.ul.ie: Tested, reworked for less branches]
[czoccolo@gmail.com: fix oops by checking pfn_valid_within()]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Corrado Zoccolo <czoccolo@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:06:56 -07:00
Thomas Weber
8839316121 Fix typos in comments
[Ss]ytem => [Ss]ystem
udpate => update
paramters => parameters
orginal => original

Signed-off-by: Thomas Weber <swirl@gmx.li>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-03-16 11:47:56 +01:00
Wu Fengguang
718a38211b mm: introduce dump_page() and print symbolic flag names
- introduce dump_page() to print the page info for debugging some error
  condition.

- convert three mm users: bad_page(), print_bad_pte() and memory offline
  failure.

- print an extra field: the symbolic names of page->flags

Example dump_page() output:

[  157.521694] page:ffffea0000a7cba8 count:2 mapcount:1 mapping:ffff88001c901791 index:0x147
[  157.525570] page flags: 0x100000000100068(uptodate|lru|active|swapbacked)

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alex Chiang <achiang@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Mel Gorman <mel@linux.vnet.ibm.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: 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>
2010-03-12 15:52:28 -08:00
Thomas Gleixner
2d30a1f631 mm: do not iterate over NR_CPUS in __zone_pcp_update()
__zone_pcp_update() iterates over NR_CPUS instead of limiting the access
to the possible cpus.  This might result in access to uninitialized areas
as the per cpu allocator only populates the per cpu memory for possible
cpus.

This problem was created as a result of the dynamic allocation of pagesets
from percpu memory that went in during the merge window - commit
99dcc3e5a9 ("this_cpu: Page allocator
conversion").

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-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>
2010-03-12 15:52:28 -08:00
David Rientjes
72f0ba0252 mm: suppress pfn range output for zones without pages
free_area_init_nodes() emits pfn ranges for all zones on the system.
There may be no pages on a higher zone, however, due to memory limitations
or the use of the mem= kernel parameter.  For example:

Zone PFN ranges:
  DMA      0x00000001 -> 0x00001000
  DMA32    0x00001000 -> 0x00100000
  Normal   0x00100000 -> 0x00100000

The implementation copies the previous zone's highest pfn, if any, as the
next zone's lowest pfn.  If its highest pfn is then greater than the
amount of addressable memory, the upper memory limit is used instead.
Thus, both the lowest and highest possible pfn for higher zones without
memory may be the same.

The pfn range for zones without memory is now shown as "empty" instead.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:26 -08:00
Rafael J. Wysocki
452aa6999e mm/pm: force GFP_NOIO during suspend/hibernation and resume
There are quite a few GFP_KERNEL memory allocations made during
suspend/hibernation and resume that may cause the system to hang, because
the I/O operations they depend on cannot be completed due to the
underlying devices being suspended.

Avoid this problem by clearing the __GFP_IO and __GFP_FS bits in
gfp_allowed_mask before suspend/hibernation and restoring the original
values of these bits in gfp_allowed_mask durig the subsequent resume.

[akpm@linux-foundation.org: fix CONFIG_PM=n linkage]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-by: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: 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>
2010-03-06 11:26:26 -08:00
KOSAKI Motohiro
93e4a89a8c mm: restore zone->all_unreclaimable to independence word
commit e815af95 ("change all_unreclaimable zone member to flags") changed
all_unreclaimable member to bit flag.  But it had an undesireble side
effect.  free_one_page() is one of most hot path in linux kernel and
increasing atomic ops in it can reduce kernel performance a bit.

Thus, this patch revert such commit partially. at least
all_unreclaimable shouldn't share memory word with other zone flags.

[akpm@linux-foundation.org: fix patch interaction]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:25 -08:00
Li Hong
fc91668eaf mm: remove free_hot_page()
free_hot_page() is just a wrapper around free_hot_cold_page() with
parameter 'cold = 0'.  After adding a clear comment for
free_hot_cold_page(), it is reasonable to remove a level of call.

[akpm@linux-foundation.org: fix build]
Signed-off-by: Li Hong <lihong.hi@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Li Ming Chun <macli@brc.ubc.ca>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Americo Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:25 -08:00
Li Hong
c475dab63a mm/page_alloc.c: adjust a call site to trace_mm_page_free_direct
Move a call of trace_mm_page_free_direct() from free_hot_page() to
free_hot_cold_page().  It is clearer and close to kmemcheck_free_shadow(),
as it is done in function __free_pages_ok().

Signed-off-by: Li Hong <lihong.hi@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Li Ming Chun <macli@brc.ubc.ca>
Cc: 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>
2010-03-06 11:26:24 -08:00
Li Hong
f650316c8b mm/page_alloc.c: remove duplicate call to trace_mm_page_free_direct
trace_mm_page_free_direct() is called in function __free_pages().  But it
is called again in free_hot_page() if order == 0 and produce duplicate
records in trace file for mm_page_free_direct event.  As below:

K-PID    CPU#    TIMESTAMP  FUNCTION
  gnome-terminal-1567  [000]  4415.246466: mm_page_free_direct: page=ffffea0003db9f40 pfn=1155800 order=0
  gnome-terminal-1567  [000]  4415.246468: mm_page_free_direct: page=ffffea0003db9f40 pfn=1155800 order=0
  gnome-terminal-1567  [000]  4415.246506: mm_page_alloc: page=ffffea0003db9f40 pfn=1155800 order=0 migratetype=0 gfp_flags=GFP_KERNEL
  gnome-terminal-1567  [000]  4415.255557: mm_page_free_direct: page=ffffea0003db9f40 pfn=1155800 order=0
  gnome-terminal-1567  [000]  4415.255557: mm_page_free_direct: page=ffffea0003db9f40 pfn=1155800 order=0

This patch removes the first call and adds a call to
trace_mm_page_free_direct() in __free_pages_ok().

Signed-off-by: Li Hong <lihong.hi@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Li Ming Chun <macli@brc.ubc.ca>
Cc: 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>
2010-03-06 11:26:24 -08:00
Linus Torvalds
a626b46e17 Merge branch 'x86-bootmem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-bootmem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (30 commits)
  early_res: Need to save the allocation name in drop_range_partial()
  sparsemem: Fix compilation on PowerPC
  early_res: Add free_early_partial()
  x86: Fix non-bootmem compilation on PowerPC
  core: Move early_res from arch/x86 to kernel/
  x86: Add find_fw_memmap_area
  Move round_up/down to kernel.h
  x86: Make 32bit support NO_BOOTMEM
  early_res: Enhance check_and_double_early_res
  x86: Move back find_e820_area to e820.c
  x86: Add find_early_area_size
  x86: Separate early_res related code from e820.c
  x86: Move bios page reserve early to head32/64.c
  sparsemem: Put mem map for one node together.
  sparsemem: Put usemap for one node together
  x86: Make 64 bit use early_res instead of bootmem before slab
  x86: Only call dma32_reserve_bootmem 64bit !CONFIG_NUMA
  x86: Make early_node_mem get mem > 4 GB if possible
  x86: Dynamically increase early_res array size
  x86: Introduce max_early_res and early_res_count
  ...
2010-03-03 08:15:05 -08:00
Yinghai Lu
2ee78f7b1d x86: Fix non-bootmem compilation on PowerPC
These build errors on some non-x86 platforms (PowerPC for example):

 mm/page_alloc.c: In function '__alloc_memory_core_early':
   mm/page_alloc.c:3468: error: implicit declaration of function 'find_early_area'
   mm/page_alloc.c:3483: error: implicit declaration of function 'reserve_early_without_check'

The function is only needed on CONFIG_NO_BOOTMEM.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Weiner <hannes@saeurebad.de>
Cc: Mel Gorman <mel@csn.ul.ie>
LKML-Reference: <4B747239.4070907@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-22 09:16:40 +01:00
Yinghai Lu
08677214e3 x86: Make 64 bit use early_res instead of bootmem before slab
Finally we can use early_res to replace bootmem for x86_64 now.

Still can use CONFIG_NO_BOOTMEM to enable it or not.

-v2: fix 32bit compiling about MAX_DMA32_PFN
-v3: folded bug fix from LKML message below

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B747239.4070907@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-12 09:41:59 -08:00
Tejun Heo
ab386128f2 Merge branch 'master' into percpu 2010-02-02 14:38:15 +09:00
Hugh Dickins
a7016235a6 mm: fix migratetype bug which slowed swapping
After memory pressure has forced it to dip into the reserves, 2.6.32's
5f8dcc2121 "page-allocator: split per-cpu
list into one-list-per-migrate-type" has been returning MIGRATE_RESERVE
pages to the MIGRATE_MOVABLE free_list: in some sense depleting reserves.

Fix that in the most straightforward way (which, considering the overheads
of alternative approaches, is Mel's preference): the right migratetype is
already in page_private(page), but free_pcppages_bulk() wasn't using it.

How did this bug show up?  As a 20% slowdown in my tmpfs loop kbuild
swapping tests, on PowerMac G5 with SLUB allocator.  Bisecting to that
commit was easy, but explaining the magnitude of the slowdown not easy.

The same effect appears, but much less markedly, with SLAB, and even
less markedly on other machines (the PowerMac divides into fewer zones
than x86, I think that may be a factor).  We guess that lumpy reclaim
of short-lived high-order pages is implicated in some way, and probably
this bug has been tickling a poor decision somewhere in page reclaim.

But instrumentation hasn't told me much, I've run out of time and
imagination to determine exactly what's going on, and shouldn't hold up
the fix any longer: it's valid, and might even fix other misbehaviours.

Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-29 10:28:09 -08:00
KOSAKI Motohiro
6ccf80eb15 page allocator: update NR_FREE_PAGES only when necessary
commit f2260e6b (page allocator: update NR_FREE_PAGES only as necessary)
made one minor regression.  if __rmqueue() was failed, NR_FREE_PAGES stat
go wrong.  this patch fixes it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reported-by: Huang Shijie <shijie8@gmail.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-16 16:53:55 -08:00
Kazuhisa Ichikawa
d2dbe08ddc mm/page_alloc: fix the range check for backward merging
The current check for 'backward merging' within add_active_range() does
not seem correct.  start_pfn must be compared against
early_node_map[i].start_pfn (and NOT against .end_pfn) to find out whether
the new region is backward-mergeable with the existing range.

Signed-off-by: Kazuhisa Ichikawa <ki@epsilou.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-16 12:15:38 -08:00
Christoph Lameter
99dcc3e5a9 this_cpu: Page allocator conversion
Use the per cpu allocator functionality to avoid per cpu arrays in struct zone.

This drastically reduces the size of struct zone for systems with large
amounts of processors and allows placement of critical variables of struct
zone in one cacheline even on very large systems.

Another effect is that the pagesets of one processor are placed near one
another. If multiple pagesets from different zones fit into one cacheline
then additional cacheline fetches can be avoided on the hot paths when
allocating memory from multiple zones.

Bootstrap becomes simpler if we use the same scheme for UP, SMP, NUMA. #ifdefs
are reduced and we can drop the zone_pcp macro.

Hotplug handling is also simplified since cpu alloc can bring up and
shut down cpu areas for a specific cpu as a whole. So there is no need to
allocate or free individual pagesets.

V7-V8:
- Explain chicken egg dilemmna with percpu allocator.

V4-V5:
- Fix up cases where per_cpu_ptr is called before irq disable
- Integrate the bootstrap logic that was separate before.

tj: Build failure in pageset_cpuup_callback() due to missing ret
    variable fixed.

Reviewed-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2010-01-05 15:34:51 +09:00
Andi Kleen
443c6f145d SYSCTL: Add a mutex to the page_alloc zone order sysctl
The zone list code clearly cannot tolerate concurrent writers (I couldn't
find any locks for that), so simply add a global mutex. No need for RCU
in this case.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-12-23 21:01:16 +01:00
Linus Torvalds
dd508ae2db Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (36 commits)
  powerpc/gc/wii: Remove get_irq_desc()
  powerpc/gc/wii: hlwd-pic: convert irq_desc.lock to raw_spinlock
  powerpc/gamecube/wii: Fix off-by-one error in ugecon/usbgecko_udbg
  powerpc/mpic: Fix problem that affinity is not updated
  powerpc/mm: Fix stupid bug in subpge protection handling
  powerpc/iseries: use DECLARE_COMPLETION_ONSTACK for non-constant completion
  powerpc: Fix MSI support on U4 bridge PCIe slot
  powerpc: Handle VSX alignment faults correctly in little-endian mode
  powerpc/mm: Fix typo of cpumask_clear_cpu()
  powerpc/mm: Fix hash_utils_64.c compile errors with DEBUG enabled.
  powerpc: Convert BUG() to use unreachable()
  powerpc/pseries: Make declarations of cpu_hotplug_driver_lock() ANSI compatible.
  powerpc/pseries: Don't panic when H_PROD fails during cpu-online.
  powerpc/mm: Fix a WARN_ON() with CONFIG_DEBUG_PAGEALLOC and CONFIG_DEBUG_VM
  powerpc/defconfigs: Set HZ=100 on pseries and ppc64 defconfigs
  powerpc/defconfigs: Disable token ring in powerpc defconfigs
  powerpc/defconfigs: Reduce 64bit vmlinux by making acenic and cramfs modules
  powerpc/pseries: Select XICS and PCI_MSI PSERIES
  powerpc/85xx: Wrong variable returned on error
  powerpc/iseries: Convert to proc_fops
  ...
2009-12-22 14:18:13 -08:00
Linus Torvalds
3981e15286 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, irq: Allow 0xff for /proc/irq/[n]/smp_affinity on an 8-cpu system
  Makefile: Unexport LC_ALL instead of clearing it
  x86: Fix objdump version check in arch/x86/tools/chkobjdump.awk
  x86: Reenable TSC sync check at boot, even with NONSTOP_TSC
  x86: Don't use POSIX character classes in gen-insn-attr-x86.awk
  Makefile: set LC_CTYPE, LC_COLLATE, LC_NUMERIC to C
  x86: Increase MAX_EARLY_RES; insufficient on 32-bit NUMA
  x86: Fix checking of SRAT when node 0 ram is not from 0
  x86, cpuid: Add "volatile" to asm in native_cpuid()
  x86, msr: msrs_alloc/free for CONFIG_SMP=n
  x86, amd: Get multi-node CPU info from NodeId MSR instead of PCI config space
  x86: Add IA32_TSC_AUX MSR and use it
  x86, msr/cpuid: Register enough minors for the MSR and CPUID drivers
  initramfs: add missing decompressor error check
  bzip2: Add missing checks for malloc returning NULL
  bzip2/lzma/gzip: pre-boot malloc doesn't return NULL on failure
2009-12-19 09:48:14 -08:00
Robert Jennings
925cc71e51 mm: Add notifier in pageblock isolation for balloon drivers
Memory balloon drivers can allocate a large amount of memory which is not
movable but could be freed to accomodate memory hotplug remove.

Prior to calling the memory hotplug notifier chain the memory in the
pageblock is isolated.  Currently, if the migrate type is not
MIGRATE_MOVABLE the isolation will not proceed, causing the memory removal
for that page range to fail.

Rather than failing pageblock isolation if the migrateteype is not
MIGRATE_MOVABLE, this patch checks if all of the pages in the pageblock,
and not on the LRU, are owned by a registered balloon driver (or other
entity) using a notifier chain.  If all of the non-movable pages are owned
by a balloon, they can be freed later through the memory notifier chain
and the range can still be isolated in set_migratetype_isolate().

Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Brian King <brking@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Gerald Schaefer <geralds@linux.vnet.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-18 14:53:36 +11:00
Yinghai Lu
3299625036 x86: Fix checking of SRAT when node 0 ram is not from 0
Found one system that boot from socket1 instead of socket0, SRAT get rejected...

[    0.000000] SRAT: Node 1 PXM 0 0-a0000
[    0.000000] SRAT: Node 1 PXM 0 100000-80000000
[    0.000000] SRAT: Node 1 PXM 0 100000000-2080000000
[    0.000000] SRAT: Node 0 PXM 1 2080000000-4080000000
[    0.000000] SRAT: Node 2 PXM 2 4080000000-6080000000
[    0.000000] SRAT: Node 3 PXM 3 6080000000-8080000000
[    0.000000] SRAT: Node 4 PXM 4 8080000000-a080000000
[    0.000000] SRAT: Node 5 PXM 5 a080000000-c080000000
[    0.000000] SRAT: Node 6 PXM 6 c080000000-e080000000
[    0.000000] SRAT: Node 7 PXM 7 e080000000-10080000000
...
[    0.000000] NUMA: Allocated memnodemap from 500000 - 701040
[    0.000000] NUMA: Using 20 for the hash shift.
[    0.000000] Adding active range (0, 0x2080000, 0x4080000) 0 entries of 3200 used
[    0.000000] Adding active range (1, 0x0, 0x96) 1 entries of 3200 used
[    0.000000] Adding active range (1, 0x100, 0x7f750) 2 entries of 3200 used
[    0.000000] Adding active range (1, 0x100000, 0x2080000) 3 entries of 3200 used
[    0.000000] Adding active range (2, 0x4080000, 0x6080000) 4 entries of 3200 used
[    0.000000] Adding active range (3, 0x6080000, 0x8080000) 5 entries of 3200 used
[    0.000000] Adding active range (4, 0x8080000, 0xa080000) 6 entries of 3200 used
[    0.000000] Adding active range (5, 0xa080000, 0xc080000) 7 entries of 3200 used
[    0.000000] Adding active range (6, 0xc080000, 0xe080000) 8 entries of 3200 used
[    0.000000] Adding active range (7, 0xe080000, 0x10080000) 9 entries of 3200 used
[    0.000000] SRAT: PXMs only cover 917504MB of your 1048566MB e820 RAM. Not used.
[    0.000000] SRAT: SRAT not used.

the early_node_map is not sorted because node0 with non zero start come first.

so try to sort it right away after all regions are registered.

also fixs refression by 8716273c (x86: Export srat physical topology)

-v2: make it more solid to handle cross node case like node0 [0,4g), [8,12g) and node1 [4g, 8g), [12g, 16g)
-v3: update comments.

Reported-and-tested-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B2579D2.3010201@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-12-16 16:43:37 -08:00
Linus Torvalds
d4220f987c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
* 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6: (34 commits)
  HWPOISON: Remove stray phrase in a comment
  HWPOISON: Try to allocate migration page on the same node
  HWPOISON: Don't do early filtering if filter is disabled
  HWPOISON: Add a madvise() injector for soft page offlining
  HWPOISON: Add soft page offline support
  HWPOISON: Undefine short-hand macros after use to avoid namespace conflict
  HWPOISON: Use new shake_page in memory_failure
  HWPOISON: Use correct name for MADV_HWPOISON in documentation
  HWPOISON: mention HWPoison in Kconfig entry
  HWPOISON: Use get_user_page_fast in hwpoison madvise
  HWPOISON: add an interface to switch off/on all the page filters
  HWPOISON: add memory cgroup filter
  memcg: add accessor to mem_cgroup.css
  memcg: rename and export try_get_mem_cgroup_from_page()
  HWPOISON: add page flags filter
  mm: export stable page flags
  HWPOISON: limit hwpoison injector to known page types
  HWPOISON: add fs/device filters
  HWPOISON: return 0 to indicate success reliably
  HWPOISON: make semantics of IGNORED/DELAYED clear
  ...
2009-12-16 12:36:49 -08:00
KAMEZAWA Hiroyuki
4365a5676f oom-kill: fix NUMA constraint check with nodemask
Fix node-oriented allocation handling in oom-kill.c I myself think of this
as a bugfix not as an ehnancement.

In these days, things are changed as
  - alloc_pages() eats nodemask as its arguments, __alloc_pages_nodemask().
  - mempolicy don't maintain its own private zonelists.
  (And cpuset doesn't use nodemask for __alloc_pages_nodemask())

So, current oom-killer's check function is wrong.

This patch does
  - check nodemask, if nodemask && nodemask doesn't cover all
    node_states[N_HIGH_MEMORY], this is CONSTRAINT_MEMORY_POLICY.
  - Scan all zonelist under nodemask, if it hits cpuset's wall
    this faiulre is from cpuset.
And
  - modifies the caller of out_of_memory not to call oom if __GFP_THISNODE.
    This doesn't change "current" behavior. If callers use __GFP_THISNODE
    it should handle "page allocation failure" by itself.

  - handle __GFP_NOFAIL+__GFP_THISNODE path.
    This is something like a FIXME but this gfpmask is not used now.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hioryu@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.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>
2009-12-16 07:19:57 -08:00
Wu Fengguang
8d22ba1b74 HWPOISON: detect free buddy pages explicitly
Most free pages in the buddy system have no PG_buddy set.
Introduce is_free_buddy_page() for detecting them reliably.

CC: Nick Piggin <npiggin@suse.de>
CC: Mel Gorman <mel@linux.vnet.ibm.com>
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
Hugh Dickins
af8e3354b4 mm: CONFIG_MMU for PG_mlocked
Remove three degrees of obfuscation, left over from when we had
CONFIG_UNEVICTABLE_LRU.  MLOCK_PAGES is CONFIG_HAVE_MLOCKED_PAGE_BIT is
CONFIG_HAVE_MLOCK is CONFIG_MMU.  rmap.o (and memory-failure.o) are only
built when CONFIG_MMU, so don't need such conditions at all.

Somehow, I feel no compulsion to remove the CONFIG_HAVE_MLOCK* lines from
169 defconfigs: leave those to evolve in due course.

Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Izik Eidus <ieidus@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Nick Piggin <npiggin@suse.de>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:17 -08:00
Mel Gorman
9d0ed60fe9 page allocator: Do not allow interrupts to use ALLOC_HARDER
Commit 341ce06f69 ("page allocator:
calculate the alloc_flags for allocation only once") altered watermark
logic slightly by allowing rt_tasks that are handling an interrupt to set
ALLOC_HARDER.  This patch brings the watermark logic more in line with
2.6.30.

This change results in a reduction of the number high-order GFP_ATOMIC
allocation failures reported.  See
http://www.gossamer-threads.com/lists/linux/kernel/1144153

[rientjes@google.com: Spotted the problem]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-12 07:25:56 -08:00
Mel Gorman
cc4a685146 page allocator: always wake kswapd when restarting an allocation attempt after direct reclaim failed
If a direct reclaim makes no forward progress, it considers whether it
should go OOM or not.  Whether OOM is triggered or not, it may retry the
allocation afterwards.  In times past, this would always wake kswapd as
well but currently, kswapd is not woken up after direct reclaim fails.
For order-0 allocations, this makes little difference but if there is a
heavy mix of higher-order allocations that direct reclaim is failing for,
it might mean that kswapd is not rewoken for higher orders as much as it
did previously.

This patch wakes up kswapd when an allocation is being retried after a
direct reclaim failure.  It would be expected that kswapd is already
awake, but this has the effect of telling kswapd to reclaim at the higher
order as well.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-12 07:25:56 -08:00
Andrew Morton
b76146ed1a revert "mm: oom analysis: add buffer cache information to show_free_areas()"
Revert

    commit 71de1ccbe1
    Author:     KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
    AuthorDate: Mon Sep 21 17:01:31 2009 -0700
    Commit:     Linus Torvalds <torvalds@linux-foundation.org>
    CommitDate: Tue Sep 22 07:17:27 2009 -0700

        mm: oom analysis: add buffer cache information to show_free_areas()

show_free_areas() is called during page allocation failures, and page
allocation failures can occur in any calling context.

But nr_blockdev_pages() takes VFS locks which should not be taken from
hard IRQ context (at least).  The result is lockdep warnings (and
deadlockability) during page allocation failures.

Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-29 07:39:27 -07:00
Linus Torvalds
db16826367 Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
* 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6: (21 commits)
  HWPOISON: Enable error_remove_page on btrfs
  HWPOISON: Add simple debugfs interface to inject hwpoison on arbitary PFNs
  HWPOISON: Add madvise() based injector for hardware poisoned pages v4
  HWPOISON: Enable error_remove_page for NFS
  HWPOISON: Enable .remove_error_page for migration aware file systems
  HWPOISON: The high level memory error handler in the VM v7
  HWPOISON: Add PR_MCE_KILL prctl to control early kill behaviour per process
  HWPOISON: shmem: call set_page_dirty() with locked page
  HWPOISON: Define a new error_remove_page address space op for async truncation
  HWPOISON: Add invalidate_inode_page
  HWPOISON: Refactor truncate to allow direct truncating of page v2
  HWPOISON: check and isolate corrupted free pages v2
  HWPOISON: Handle hardware poisoned pages in try_to_unmap
  HWPOISON: Use bitmask/action code for try_to_unmap behaviour
  HWPOISON: x86: Add VM_FAULT_HWPOISON handling to x86 page fault handler v2
  HWPOISON: Add poison check to page fault handling
  HWPOISON: Add basic support for poisoned pages in fault handler v3
  HWPOISON: Add new SIGBUS error codes for hardware poison signals
  HWPOISON: Add support for poison swap entries v2
  HWPOISON: Export some rmap vma locking to outside world
  ...
2009-09-24 07:53:22 -07:00