summaryrefslogtreecommitdiff
path: root/include
diff options
context:
space:
mode:
authorMel Gorman <mgorman@suse.de>2013-07-03 15:01:50 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-07-03 16:07:28 -0700
commitd43006d503ac921c7df4f94d13c17db6f13c9d26 (patch)
tree3adf95869d1821cd5360c81dca790b3203608555 /include
parent9aa41348a8d11427feec350b21dcdd4330fd20c4 (diff)
mm: vmscan: have kswapd writeback pages based on dirty pages encountered, not priority
Currently kswapd queues dirty pages for writeback if scanning at an elevated priority but the priority kswapd scans at is not related to the number of unqueued dirty encountered. Since commit "mm: vmscan: Flatten kswapd priority loop", the priority is related to the size of the LRU and the zone watermark which is no indication as to whether kswapd should write pages or not. This patch tracks if an excessive number of unqueued dirty pages are being encountered at the end of the LRU. If so, it indicates that dirty pages are being recycled before flusher threads can clean them and flags the zone so that kswapd will start writing pages until the zone is balanced. Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Tested-by: Zlatko Calusic <zcalusic@bitsync.net> Cc: dormando <dormando@rydia.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
-rw-r--r--include/linux/mmzone.h9
1 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 5c76737d836b..2aaf72f7e345 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -495,6 +495,10 @@ typedef enum {
ZONE_CONGESTED, /* zone has many dirty pages backed by
* a congested BDI
*/
+ ZONE_TAIL_LRU_DIRTY, /* reclaim scanning has recently found
+ * many dirty file pages at the tail
+ * of the LRU.
+ */
} zone_flags_t;
static inline void zone_set_flag(struct zone *zone, zone_flags_t flag)
@@ -517,6 +521,11 @@ static inline int zone_is_reclaim_congested(const struct zone *zone)
return test_bit(ZONE_CONGESTED, &zone->flags);
}
+static inline int zone_is_reclaim_dirty(const struct zone *zone)
+{
+ return test_bit(ZONE_TAIL_LRU_DIRTY, &zone->flags);
+}
+
static inline int zone_is_reclaim_locked(const struct zone *zone)
{
return test_bit(ZONE_RECLAIM_LOCKED, &zone->flags);