vmscan: recalculate lru_pages on each priority

shrink_zones() need relatively long time and lru_pages can change
dramatically during shrink_zones().  So lru_pages should be recalculated
for each priority.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 5b594d6..6dafa45 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1787,7 +1787,6 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
        bool all_unreclaimable;
        unsigned long total_scanned = 0;
        struct reclaim_state *reclaim_state = current->reclaim_state;
-       unsigned long lru_pages = 0;
        struct zoneref *z;
        struct zone *zone;
        enum zone_type high_zoneidx = gfp_zone(sc->gfp_mask);
@@ -1798,18 +1797,6 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
 
        if (scanning_global_lru(sc))
                count_vm_event(ALLOCSTALL);
-       /*
-        * mem_cgroup will not do shrink_slab.
-        */
-       if (scanning_global_lru(sc)) {
-               for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
-
-                       if (!cpuset_zone_allowed_hardwall(zone, GFP_KERNEL))
-                               continue;
-
-                       lru_pages += zone_reclaimable_pages(zone);
-               }
-       }
 
        for (priority = DEF_PRIORITY; priority >= 0; priority--) {
                sc->nr_scanned = 0;
@@ -1821,6 +1808,14 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
                 * over limit cgroups
                 */
                if (scanning_global_lru(sc)) {
+                       unsigned long lru_pages = 0;
+                       for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
+                               if (!cpuset_zone_allowed_hardwall(zone, GFP_KERNEL))
+                                       continue;
+
+                               lru_pages += zone_reclaimable_pages(zone);
+                       }
+
                        shrink_slab(sc->nr_scanned, sc->gfp_mask, lru_pages);
                        if (reclaim_state) {
                                sc->nr_reclaimed += reclaim_state->reclaimed_slab;