Merge tag 'llvmlinux-for-v3.15' of git://git.linuxfoundation.org/llvmlinux/kernel

[firefly-linux-kernel-4.4.55.git] / mm / vmscan.c

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 1f56a80a7c41442eefa86d7fe82387570cb3bfd0..9b6497eda8067857d7008787868e365882820db3 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1862,7 +1862,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc,
        struct zone *zone = lruvec_zone(lruvec);
        unsigned long anon_prio, file_prio;
        enum scan_balance scan_balance;
-       unsigned long anon, file, free;
+       unsigned long anon, file;
        bool force_scan = false;
        unsigned long ap, fp;
        enum lru_list lru;
@@ -1915,20 +1915,6 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc,
        file  = get_lru_size(lruvec, LRU_ACTIVE_FILE) +
                get_lru_size(lruvec, LRU_INACTIVE_FILE);
 
-       /*
-        * If it's foreseeable that reclaiming the file cache won't be
-        * enough to get the zone back into a desirable shape, we have
-        * to swap.  Better start now and leave the - probably heavily
-        * thrashing - remaining file pages alone.
-        */
-       if (global_reclaim(sc)) {
-               free = zone_page_state(zone, NR_FREE_PAGES);
-               if (unlikely(file + free <= high_wmark_pages(zone))) {
-                       scan_balance = SCAN_ANON;
-                       goto out;
-               }
-       }
-
        /*
         * There is enough inactive page cache, do not reclaim
         * anything from the anonymous working set right now.
@@ -2314,15 +2300,18 @@ static bool shrink_zones(struct zonelist *zonelist, struct scan_control *sc)
        unsigned long lru_pages = 0;
        bool aborted_reclaim = false;
        struct reclaim_state *reclaim_state = current->reclaim_state;
+       gfp_t orig_mask;
        struct shrink_control shrink = {
                .gfp_mask = sc->gfp_mask,
        };
+       enum zone_type requested_highidx = gfp_zone(sc->gfp_mask);
 
        /*
         * If the number of buffer_heads in the machine exceeds the maximum
         * allowed level, force direct reclaim to scan the highmem zone as
         * highmem pages could be pinning lowmem pages storing buffer_heads
         */
+       orig_mask = sc->gfp_mask;
        if (buffer_heads_over_limit)
                sc->gfp_mask |= __GFP_HIGHMEM;
 
@@ -2356,7 +2345,8 @@ static bool shrink_zones(struct zonelist *zonelist, struct scan_control *sc)
                                 * noticeable problem, like transparent huge
                                 * page allocations.
                                 */
-                               if (compaction_ready(zone, sc)) {
+                               if ((zonelist_zone_idx(z) <= requested_highidx)
+                                   && compaction_ready(zone, sc)) {
                                        aborted_reclaim = true;
                                        continue;
                                }
@@ -2393,6 +2383,12 @@ static bool shrink_zones(struct zonelist *zonelist, struct scan_control *sc)
                }
        }
 
+       /*
+        * Restore to original mask to avoid the impact on the caller if we
+        * promoted it to __GFP_HIGHMEM.
+        */
+       sc->gfp_mask = orig_mask;
+
        return aborted_reclaim;
 }