mm: split_free_page ignore memory watermarks for CMA

Memory watermarks were sometimes preventing CMA allocations
in low memory.

Change-Id: I550ec987cbd6bc6dadd72b4a764df20cd0758479
Signed-off-by: Liam Mark <lmark@codeaurora.org>
mm: Add is_cma_pageblock definition

Bring back the is_cma_pageblock definition for determining if a
page is CMA or not.

Change-Id: I39fd546e22e240b752244832c79514f109c8e84b
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
mm: Don't use CMA pages for writes

If CMA pages are used for writes, the writes may not complete
fast enough for CMA to be allocated within a reasonable amount
of time. If we get a CMA page, get another one to use instead.

Change-Id: I19d8ba655da7525d68d5947337d500566998971c
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
cma: fix race condition on a page

cruel, brute-force method for letting cma/migration to
finish its job without stealing the lock
migration_entry_wait() and creating a live-lock on the
faulted page. This patch solves the case of
page->_count == 2 migration failure.

Change-Id: Ia94542a80e44a213831291af289bbf5ee6880bfd
Signed-off-by: Heesub Shin <heesub.shin@samsung.com>
Reviewed-on: http://165.213.202.130:8080/39341
Tested-by: System S/W SCM <scm.systemsw@samsung.com>
Tested-by: Dongjun Shin <d.j.shin@samsung.com>
Reviewed-by: Hyunju Ahn <hyunju.ahn@samsung.com>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
fs: fuse: Workaround for CMA migration

The FUSE file system may hold references to pages for long
periods of time, preventing migration from occuring. If a CMA
page is used here, CMA allocations may fail. Work around this
by swapping out a CMA page for a non-CMA page when working with
the FUSE file system.

Change-Id: Id763ea833ee125c8732ae3759ec9e20d94aa8424
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
mm: Use correct define for CMA features

CMA features may ifdef out parts of the code with
CONFIG_CMA. Older code uses CONFIG_DMA_CMA. Switch
to using the newer CONFIG_CMA to ensure the code gets
compiled when needed.

Change-Id: I2ed8020e7b2f8319382b10c7c7c6818eb52995b6
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
cma : use migrate_prep() instead of migrate_prep_local()

__alloc_contig_migrate_range() should use all possible ways to get all the
pages migrated from the given memory range, so pruning per-cpu lru lists
for all CPUs is required, regadless the cost of such operation. Otherwise
some pages which got stuck at per-cpu lru list might get missed by
migration procedure causing the contiguous allocation to fail.

Change-Id: I70cc0864c57dd49e89f57797122a3fd0f300647a
Signed-off-by: woojoong.lee <woojoong.lee@samsung.com>
Reviewed-on: http://165.213.202.130:8080/43063
Tested-by: System S/W SCM <scm.systemsw@samsung.com>
Reviewed-by: daeho jeong <daeho.jeong@samsung.com>
Reviewed-by: Jeong-Ho Kim <jammer@samsung.com>
Tested-by: Jeong-Ho Kim <jammer@samsung.com>
[lauraa@codeaurora.org: Applied to correct file]
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
mm: make counts of CMA free pages correct

Both patches needed, second patch (among other things) fixes
a bug in the first.

commit 2139cbe627b8910ded55148f87ee10f7485408ed
Author: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Date:   Mon Oct 8 16:32:00 2012 -0700

    cma: fix counting of isolated pages

    Isolated free pages shouldn't be accounted to NR_FREE_PAGES counter.  Fix
    it by properly decreasing/increasing NR_FREE_PAGES counter in
    set_migratetype_isolate()/unset_migratetype_isolate() and removing counter
    adjustment for isolated pages from free_one_page() and split_free_page().

    Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
    Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
    Cc: Marek Szyprowski <m.szyprowski@samsung.com>
    Cc: Michal Nazarewicz <mina86@mina86.com>
    Cc: Minchan Kim <minchan@kernel.org>
    Cc: Mel Gorman <mgorman@suse.de>
    Cc: Hugh Dickins <hughd@google.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
    [lbassel@codeaurora.org: backport from 3.7, small changes needed]
    Signed-off-by: Larry Bassel <lbassel@codeaurora.org>

commit d1ce749a0db12202b711d1aba1d29e823034648d
Author: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Date:   Mon Oct 8 16:32:02 2012 -0700

    cma: count free CMA pages

    Add NR_FREE_CMA_PAGES counter to be later used for checking watermark in
    __zone_watermark_ok().  For simplicity and to avoid #ifdef hell make this
    counter always available (not only when CONFIG_CMA=y).

    [akpm@linux-foundation.org: use conventional migratetype naming]
    Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
    Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
    Cc: Marek Szyprowski <m.szyprowski@samsung.com>
    Cc: Michal Nazarewicz <mina86@mina86.com>
    Cc: Minchan Kim <minchan@kernel.org>
    Cc: Mel Gorman <mgorman@suse.de>
    Cc: Hugh Dickins <hughd@google.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
    [lbassel@codeaurora.org: backport from 3.7, small changes needed]
    Signed-off-by: Larry Bassel <lbassel@codeaurora.org>

Change-Id: I3c694620021efa5ddee1b9dcd87f95b63ad8557c
Signed-off-by: Larry Bassel <lbassel@codeaurora.org>
mm: show migration types in show_mem

This is useful to diagnose the reason for page allocation failure for
cases where there appear to be several free pages.

Example, with this alloc_pages(GFP_ATOMIC) failure:

 swapper/0: page allocation failure: order:0, mode:0x0
 ...
 Mem-info:
 Normal per-cpu:
 CPU    0: hi:   90, btch:  15 usd:  48
 CPU    1: hi:   90, btch:  15 usd:  21
 active_anon:0 inactive_anon:0 isolated_anon:0
  active_file:0 inactive_file:84 isolated_file:0
  unevictable:0 dirty:0 writeback:0 unstable:0
  free:4026 slab_reclaimable:75 slab_unreclaimable:484
  mapped:0 shmem:0 pagetables:0 bounce:0
 Normal free:16104kB min:2296kB low:2868kB high:3444kB active_anon:0kB
 inactive_anon:0kB active_file:0kB inactive_file:336kB unevictable:0kB
 isolated(anon):0kB isolated(file):0kB present:331776kB mlocked:0kB
 dirty:0kB writeback:0kB mapped:0kB shmem:0kB slab_reclaimable:300kB
 slab_unreclaimable:1936kB kernel_stack:328kB pagetables:0kB unstable:0kB
 bounce:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no
 lowmem_reserve[]: 0 0

Before the patch, it's hard (for me, at least) to say why all these free
chunks weren't considered for allocation:

 Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 1*256kB 1*512kB
 1*1024kB 1*2048kB 3*4096kB = 16128kB

After the patch, it's obvious that the reason is that all of these are
in the MIGRATE_CMA (C) freelist:

 Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 1*256kB (C) 1*512kB
 (C) 1*1024kB (C) 1*2048kB (C) 3*4096kB (C) = 16128kB

Change-Id: Ic5fe77d762e0c03715bfb917774e7c4f03ac43f5
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.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>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
cma: fix watermark checking

* Add ALLOC_CMA alloc flag and pass it to [__]zone_watermark_ok()
  (from Minchan Kim).

* During watermark check decrease available free pages number by
  free CMA pages number if necessary (unmovable allocations cannot
  use pages from CMA areas).

Change-Id: Ibd069b028eb80b70701c1b81cb28a503d8265be0
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[lauraa@codeaurora.org: context fixups]
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
cma: redirect page allocation to CMA

CMA pages are designed to be used as fallback for movable allocations
and cannot be used for non-movable allocations. If CMA pages are
utilized poorly, non-movable allocations may end up getting starved if
all regular movable pages are allocated and the only pages left are
CMA. Always using CMA pages first creates unacceptable performance
problems. As a midway alternative, use CMA pages for certain
userspace allocations. The userspace pages can be migrated or dropped
quickly which giving decent utilization.

Change-Id: I6165dda01b705309eebabc6dfa67146b7a95c174
CRs-Fixed: 452508
[lauraa@codeaurora.org: Missing CONFIG_CMA guards, add commit text]
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
mm: Don't put CMA pages on per cpu lists

CMA allocations rely on being able to migrate pages out
quickly to fulfill the allocations. Most use cases for
movable allocations meet this requirement. File system
allocations may take an unaccpetably long time to
migrate, which creates delays from CMA. Prevent CMA
pages from ending up on the per-cpu lists to avoid
code paths grabbing CMA pages on the fast path. CMA
pages can still be allocated as a fallback under tight
memory pressure.

CRs-Fixed: 452508
Change-Id: I79a28f697275a2a1870caabae53c8ea345b4b47d
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>