Mel Gorman 397d9c507f mm: compaction: determine if dirty pages can be migrated without blocking within ->migratepage ... commit b969c4ab9f upstream. Stable note: Not tracked in Bugzilla. A fix aimed at preserving page aging information by reducing LRU list churning had the side-effect of reducing THP allocation success rates. This was part of a series to restore the success rates while preserving the reclaim fix. Asynchronous compaction is used when allocating transparent hugepages to avoid blocking for long periods of time. Due to reports of stalling, there was a debate on disabling synchronous compaction but this severely impacted allocation success rates. Part of the reason was that many dirty pages are skipped in asynchronous compaction by the following check; if (PageDirty(page) && !sync && mapping->a_ops->migratepage != migrate_page) rc = -EBUSY; This skips over all mapping aops using buffer_migrate_page() even though it is possible to migrate some of these pages without blocking. This patch updates the ->migratepage callback with a "sync" parameter. It is the responsibility of the callback to fail gracefully if migration would block. Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Dave Jones <davej@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Andy Isaacson <adi@hexapodia.org> Cc: Nai Xia <nai.xia@gmail.com> Cc: Johannes Weiner <jweiner@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2012-08-01 12:27:17 -07:00
..
acpi	ACPI: Store SRAT table revision	2012-01-25 17:24:57 -08:00
asm-generic	mm: pmd_read_atomic: fix 32bit PAE pmd walk vs pmd_populate SMP race condition	2012-06-10 00:32:57 +09:00
crypto
drm	drm/radeon/kms: add new BTC PCI ids	2012-06-10 00:33:04 +09:00
keys
linux	mm: compaction: determine if dirty pages can be migrated without blocking within ->migratepage	2012-08-01 12:27:17 -07:00
math-emu
media
mtd
net	bonding: Fix corrupted queue_mapping	2012-07-16 08:47:37 -07:00
pcmcia
rdma
rxrpc
scsi
sound
target	target: Set additional sense length field in sense data	2012-01-25 17:25:00 -08:00
trace	mm: change isolate mode from #define to bitwise type	2012-08-01 12:27:16 -07:00
video	OMAPDSS: HDMI: PHY burnout fix	2012-03-12 10:32:59 -07:00
xen	xen/xenbus: Reject replies with payload > XENSTORE_PAYLOAD_MAX.	2012-01-25 17:24:41 -08:00
Kbuild