mm: zone_reclaim: make isolate_lru_page() filter-aware
authorMinchan Kim <minchan.kim@gmail.com>
Tue, 1 Nov 2011 00:06:55 +0000 (17:06 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 1 Nov 2011 00:30:44 +0000 (17:30 -0700)
commitf80c0673610e36ae29d63e3297175e22f70dde5f
tree0a6aab3b637fa75961224e9261eb544156672c34
parent39deaf8585152f1a35c1676d3d7dc6ae0fb65967
mm: zone_reclaim: make isolate_lru_page() filter-aware

In __zone_reclaim case, we don't want to shrink mapped page.  Nonetheless,
we have isolated mapped page and re-add it into LRU's head.  It's
unnecessary CPU overhead and makes LRU churning.

Of course, when we isolate the page, the page might be mapped but when we
try to migrate the page, the page would be not mapped.  So it could be
migrated.  But race is rare and although it happens, it's no big deal.

Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/mmzone.h
mm/vmscan.c