tree 727e8edb99d9d1ee8614eaf2f74ab285508b9d14
parent 05fd3fd3a071f795301404526fbbe0bf6b04bbbe
author Mel Gorman <mgorman@suse.de> 1349738952 -0700
committer Laura Abbott <lauraa@codeaurora.org> 1371576280 -0700

mm: compaction: capture a suitable high-order page immediately when it is made available

While compaction is migrating pages to free up large contiguous blocks
for allocation it races with other allocation requests that may steal
these blocks or break them up.  This patch alters direct compaction to
capture a suitable free page as soon as it becomes available to reduce
this race.  It uses similar logic to split_free_page() to ensure that
watermarks are still obeyed.

Change-Id: I46fc38ca67bc50aa7a77a59255caf563f50343a9
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 1fb3f8ca0e9222535a39b884cb67a34628411b9f
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>