vmscan: avoid setting zone congested if no page dirty
authorShaohua Li <shaohua.li@intel.com>
Thu, 11 Nov 2010 22:05:17 +0000 (14:05 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 12 Nov 2010 15:55:31 +0000 (07:55 -0800)
commit1dce071e18b7264457d17c0dec4c7e430bfaee7d
treeced52f7f8e4177f9ea37f891f4d33d0a5109e651
parent38715258aa2e8cd94bd4aafadc544e5104efd551
vmscan: avoid setting zone congested if no page dirty

nr_dirty and nr_congested are increased only when the page is dirty.  So
if all pages are clean, both them will be zero.  In this case, we should
not mark the zone congested.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Minchan Kim <minchan.kim@gmail.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>
mm/vmscan.c