]> git.karo-electronics.de Git - karo-tx-linux.git/commitdiff
mm: test PageSwapBacked in lumpy reclaim
authorHugh Dickins <hughd@google.com>
Tue, 10 Jan 2012 23:08:33 +0000 (15:08 -0800)
committerBen Hutchings <ben@decadent.org.uk>
Thu, 2 Aug 2012 13:37:35 +0000 (14:37 +0100)
commit 043bcbe5ec51e0478ef2b44acef17193e01d7f70 upstream.

Stable note: Not tracked in Bugzilla. There were reports of shared
mapped pages being unfairly reclaimed in comparison to older kernels.
This is being addressed over time. Even though the subject
refers to lumpy reclaim, it impacts compaction as well.

Lumpy reclaim does well to stop at a PageAnon when there's no swap, but
better is to stop at any PageSwapBacked, which includes shmem/tmpfs too.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.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>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
mm/vmscan.c

index ba763be05b5b6357fafc26fbb814a3716b861df4..b9eaa06c6e6ea2ea36e71bbad60f81501c54052e 100644 (file)
@@ -1215,7 +1215,7 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
                         * anon page which don't already have a swap slot is
                         * pointless.
                         */
-                       if (nr_swap_pages <= 0 && PageAnon(cursor_page) &&
+                       if (nr_swap_pages <= 0 && PageSwapBacked(cursor_page) &&
                            !PageSwapCache(cursor_page))
                                break;