rmap: remove __anon_vma_link() declaration

[deliverable/linux.git] / mm / vmscan.c

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 87e4d6a6dc11f50e1d96a5aeea8400305c4408fb..ae3bf0a09cdd4ea87b1526aef9775d67ddae7b0c 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1642,18 +1642,6 @@ static void move_active_pages_to_lru(struct zone *zone,
        unsigned long pgmoved = 0;
        struct page *page;
 
-       if (buffer_heads_over_limit) {
-               spin_unlock_irq(&zone->lru_lock);
-               list_for_each_entry(page, list, lru) {
-                       if (page_has_private(page) && trylock_page(page)) {
-                               if (page_has_private(page))
-                                       try_to_release_page(page, 0);
-                               unlock_page(page);
-                       }
-               }
-               spin_lock_irq(&zone->lru_lock);
-       }
-
        while (!list_empty(list)) {
                struct lruvec *lruvec;
 
@@ -1735,6 +1723,14 @@ static void shrink_active_list(unsigned long nr_to_scan,
                        continue;
                }
 
+               if (unlikely(buffer_heads_over_limit)) {
+                       if (page_has_private(page) && trylock_page(page)) {
+                               if (page_has_private(page))
+                                       try_to_release_page(page, 0);
+                               unlock_page(page);
+                       }
+               }
+
                if (page_referenced(page, 0, mz->mem_cgroup, &vm_flags)) {
                        nr_rotated += hpage_nr_pages(page);
                        /*
@@ -2238,6 +2234,14 @@ static bool shrink_zones(int priority, struct zonelist *zonelist,
        unsigned long nr_soft_scanned;
        bool aborted_reclaim = false;
 
+       /*
+        * 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
+        */
+       if (buffer_heads_over_limit)
+               sc->gfp_mask |= __GFP_HIGHMEM;
+
        for_each_zone_zonelist_nodemask(zone, z, zonelist,
                                        gfp_zone(sc->gfp_mask), sc->nodemask) {
                if (!populated_zone(zone))
@@ -2727,6 +2731,17 @@ loop_again:
                         */
                        age_active_anon(zone, &sc, priority);
 
+                       /*
+                        * If the number of buffer_heads in the machine
+                        * exceeds the maximum allowed level and this node
+                        * has a highmem zone, force kswapd to reclaim from
+                        * it to relieve lowmem pressure.
+                        */
+                       if (buffer_heads_over_limit && is_highmem_idx(i)) {
+                               end_zone = i;
+                               break;
+                       }
+
                        if (!zone_watermark_ok_safe(zone, order,
                                        high_wmark_pages(zone), 0, 0)) {
                                end_zone = i;
@@ -2802,7 +2817,8 @@ loop_again:
                                                COMPACT_SKIPPED)
                                testorder = 0;
 
-                       if (!zone_watermark_ok_safe(zone, testorder,
+                       if ((buffer_heads_over_limit && is_highmem_idx(i)) ||
+                                   !zone_watermark_ok_safe(zone, order,
                                        high_wmark_pages(zone) + balance_gap,
                                        end_zone, 0)) {
                                shrink_zone(priority, zone, &sc);