linux/include
Vlastimil Babka 97d47a65be mm, compaction: simplify deferred compaction
Since commit 53853e2d2b ("mm, compaction: defer each zone individually
instead of preferred zone"), compaction is deferred for each zone where
sync direct compaction fails, and reset where it succeeds.  However, it
was observed that for DMA zone compaction often appeared to succeed
while subsequent allocation attempt would not, due to different outcome
of watermark check.

In order to properly defer compaction in this zone, the candidate zone
has to be passed back to __alloc_pages_direct_compact() and compaction
deferred in the zone after the allocation attempt fails.

The large source of mismatch between watermark check in compaction and
allocation was the lack of alloc_flags and classzone_idx values in
compaction, which has been fixed in the previous patch.  So with this
problem fixed, we can simplify the code by removing the candidate_zone
parameter and deferring in __alloc_pages_direct_compact().

After this patch, the compaction activity during stress-highalloc
benchmark is still somewhat increased, but it's negligible compared to the
increase that occurred without the better watermark checking.  This
suggests that it is still possible to apparently succeed in compaction but
fail to allocate, possibly due to parallel allocation activity.

[akpm@linux-foundation.org: fix build]
Suggested-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Rik van Riel <riel@redhat.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>
2014-12-10 17:41:06 -08:00
..
acpi ACPI and power management updates for 3.18-rc2 2014-10-24 11:29:31 -07:00
asm-generic Merge branch 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-12-10 09:34:43 -08:00
clocksource
crypto crypto: LLVMLinux: Add macro to remove use of VLAIS in crypto code 2014-10-14 10:51:22 +02:00
drm drm/radeon: remove invalid pci id 2014-10-28 10:44:36 -04:00
dt-bindings ARM: SoC DT updates for 3.19 2014-12-09 14:57:37 -08:00
keys KEYS: Restore partial ID matching functionality for asymmetric keys 2014-10-06 15:21:05 +01:00
kvm arm/arm64: KVM: Fix BE accesses to GICv2 EISR and ELRSR regs 2014-10-16 10:57:41 +02:00
linux mm, compaction: simplify deferred compaction 2014-12-10 17:41:06 -08:00
math-emu
media Merge branch 'patchwork' into v4l_for_linus 2014-10-09 14:00:54 -03:00
memory
misc cxl: Add new header for call backs and structs 2014-10-08 20:15:43 +11:00
net mm: memcontrol: lockless page counters 2014-12-10 17:41:04 -08:00
pcmcia
ras PCI/AER: Rename PCI_ERR_UNC_TRAIN to PCI_ERR_UNC_UND 2014-09-25 09:42:40 -06:00
rdma IB/mlx5, iser, isert: Add Signature API additions 2014-10-09 00:10:53 -07:00
rxrpc
scsi Merge remote-tracking branch 'scsi-queue/drivers-for-3.19' into for-linus 2014-12-08 07:42:25 -08:00
soc Merge branch 'at91/cleanup5' into next/drivers 2014-12-08 18:29:20 +01:00
sound ALSA: pcm: Add big-endian DSD sample formats and fix XMOS DSD sample format 2014-11-21 15:13:28 +01:00
target target: Add force_pr_aptpl device attribute 2014-10-04 05:41:20 +00:00
trace Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-12-09 21:21:34 -08:00
uapi Merge branch 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-12-10 09:34:43 -08:00
video fbdev changes for 3.18 2014-10-18 18:03:02 -07:00
xen xen: remove DEFINE_XENBUS_DRIVER() macro 2014-10-06 10:27:57 +01:00
Kbuild