1 files changed, 56 insertions, 24 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index c9177202c8ce..7e0116150dc7 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -202,6 +202,14 @@ void unregister_shrinker(struct shrinker *shrinker)
 }
 EXPORT_SYMBOL(unregister_shrinker);
 
+static inline int do_shrinker_shrink(struct shrinker *shrinker,
+                                     struct shrink_control *sc,
+                                     unsigned long nr_to_scan)
+{
+        sc->nr_to_scan = nr_to_scan;
+        return (*shrinker->shrink)(shrinker, sc);
+}
+
 #define SHRINK_BATCH 128
 /*
  * Call the shrink functions to age shrinkable caches
@@ -222,25 +230,29 @@ EXPORT_SYMBOL(unregister_shrinker);
  *
  * Returns the number of slab objects which we shrunk.
  */
-unsigned long shrink_slab(unsigned long scanned, gfp_t gfp_mask,
-                        unsigned long lru_pages)
+unsigned long shrink_slab(struct shrink_control *shrink,
+                          unsigned long nr_pages_scanned,
+                          unsigned long lru_pages)
 {
         struct shrinker *shrinker;
         unsigned long ret = 0;
 
-        if (scanned == 0)
-                scanned = SWAP_CLUSTER_MAX;
+        if (nr_pages_scanned == 0)
+                nr_pages_scanned = SWAP_CLUSTER_MAX;
 
-        if (!down_read_trylock(&shrinker_rwsem))
-                return 1;       /* Assume we'll be able to shrink next time */
+        if (!down_read_trylock(&shrinker_rwsem)) {
+                /* Assume we'll be able to shrink next time */
+                ret = 1;
+                goto out;
+        }
 
         list_for_each_entry(shrinker, &shrinker_list, list) {
                 unsigned long long delta;
                 unsigned long total_scan;
                 unsigned long max_pass;
 
-                max_pass = (*shrinker->shrink)(shrinker, 0, gfp_mask);
-                delta = (4 * scanned) / shrinker->seeks;
+                max_pass = do_shrinker_shrink(shrinker, shrink, 0);
+                delta = (4 * nr_pages_scanned) / shrinker->seeks;
                 delta *= max_pass;
                 do_div(delta, lru_pages + 1);
                 shrinker->nr += delta;
@@ -267,9 +279,9 @@ unsigned long shrink_slab(unsigned long scanned, gfp_t gfp_mask,
                         int shrink_ret;
                         int nr_before;
 
-                        nr_before = (*shrinker->shrink)(shrinker, 0, gfp_mask);
-                        shrink_ret = (*shrinker->shrink)(shrinker, this_scan,
-                                                                gfp_mask);
+                        nr_before = do_shrinker_shrink(shrinker, shrink, 0);
+                        shrink_ret = do_shrinker_shrink(shrinker, shrink,
+                                                        this_scan);
                         if (shrink_ret == -1)
                                 break;
                         if (shrink_ret < nr_before)
@@ -283,6 +295,8 @@ unsigned long shrink_slab(unsigned long scanned, gfp_t gfp_mask,
                 shrinker->nr += total_scan;
         }
         up_read(&shrinker_rwsem);
+out:
+        cond_resched();
         return ret;
 }
 
@@ -1202,13 +1216,16 @@ int isolate_lru_page(struct page *page)
 {
         int ret = -EBUSY;
 
+        VM_BUG_ON(!page_count(page));
+
         if (PageLRU(page)) {
                 struct zone *zone = page_zone(page);
 
                 spin_lock_irq(&zone->lru_lock);
-                if (PageLRU(page) && get_page_unless_zero(page)) {
+                if (PageLRU(page)) {
                         int lru = page_lru(page);
                         ret = 0;
+                        get_page(page);
                         ClearPageLRU(page);
 
                         del_page_from_lru_list(zone, page, lru);
@@ -2027,7 +2044,8 @@ static bool all_unreclaimable(struct zonelist *zonelist,
  *              else, the number of pages reclaimed
  */
 static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
-                                        struct scan_control *sc)
+                                        struct scan_control *sc,
+                                        struct shrink_control *shrink)
 {
         int priority;
         unsigned long total_scanned = 0;
@@ -2061,7 +2079,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
                                 lru_pages += zone_reclaimable_pages(zone);
                         }
 
-                        shrink_slab(sc->nr_scanned, sc->gfp_mask, lru_pages);
+                        shrink_slab(shrink, sc->nr_scanned, lru_pages);
                         if (reclaim_state) {
                                 sc->nr_reclaimed += reclaim_state->reclaimed_slab;
                                 reclaim_state->reclaimed_slab = 0;
@@ -2133,12 +2151,15 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
                 .mem_cgroup = NULL,
                 .nodemask = nodemask,
         };
+        struct shrink_control shrink = {
+                .gfp_mask = sc.gfp_mask,
+        };
 
         trace_mm_vmscan_direct_reclaim_begin(order,
                                 sc.may_writepage,
                                 gfp_mask);
 
-        nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
+        nr_reclaimed = do_try_to_free_pages(zonelist, &sc, &shrink);
 
         trace_mm_vmscan_direct_reclaim_end(nr_reclaimed);
 
@@ -2198,17 +2219,20 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont,
                 .order = 0,
                 .mem_cgroup = mem_cont,
                 .nodemask = NULL, /* we don't care the placement */
+                .gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
+                                (GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK),
+        };
+        struct shrink_control shrink = {
+                .gfp_mask = sc.gfp_mask,
         };
 
-        sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
-                        (GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK);
         zonelist = NODE_DATA(numa_node_id())->node_zonelists;
 
         trace_mm_vmscan_memcg_reclaim_begin(0,
                                             sc.may_writepage,
                                             sc.gfp_mask);
 
-        nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
+        nr_reclaimed = do_try_to_free_pages(zonelist, &sc, &shrink);
 
         trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed);
 
@@ -2287,7 +2311,7 @@ static bool sleeping_prematurely(pg_data_t *pgdat, int order, long remaining,
          * must be balanced
          */
         if (order)
-                return pgdat_balanced(pgdat, balanced, classzone_idx);
+                return !pgdat_balanced(pgdat, balanced, classzone_idx);
         else
                 return !all_zones_ok;
 }
@@ -2336,6 +2360,9 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order,
                 .order = order,
                 .mem_cgroup = NULL,
         };
+        struct shrink_control shrink = {
+                .gfp_mask = sc.gfp_mask,
+        };
 loop_again:
         total_scanned = 0;
         sc.nr_reclaimed = 0;
@@ -2435,8 +2462,7 @@ loop_again:
                                         end_zone, 0))
                                 shrink_zone(priority, zone, &sc);
                         reclaim_state->reclaimed_slab = 0;
-                        nr_slab = shrink_slab(sc.nr_scanned, GFP_KERNEL,
-                                                lru_pages);
+                        nr_slab = shrink_slab(&shrink, sc.nr_scanned, lru_pages);
                         sc.nr_reclaimed += reclaim_state->reclaimed_slab;
                         total_scanned += sc.nr_scanned;
 
@@ -2788,7 +2814,10 @@ unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
                 .swappiness = vm_swappiness,
                 .order = 0,
         };
-        struct zonelist * zonelist = node_zonelist(numa_node_id(), sc.gfp_mask);
+        struct shrink_control shrink = {
+                .gfp_mask = sc.gfp_mask,
+        };
+        struct zonelist *zonelist = node_zonelist(numa_node_id(), sc.gfp_mask);
         struct task_struct *p = current;
         unsigned long nr_reclaimed;
 
@@ -2797,7 +2826,7 @@ unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
         reclaim_state.reclaimed_slab = 0;
         p->reclaim_state = &reclaim_state;
 
-        nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
+        nr_reclaimed = do_try_to_free_pages(zonelist, &sc, &shrink);
 
         p->reclaim_state = NULL;
         lockdep_clear_current_reclaim_state();
@@ -2972,6 +3001,9 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
                 .swappiness = vm_swappiness,
                 .order = order,
         };
+        struct shrink_control shrink = {
+                .gfp_mask = sc.gfp_mask,
+        };
         unsigned long nr_slab_pages0, nr_slab_pages1;
 
         cond_resched();
@@ -3013,7 +3045,7 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
                         unsigned long lru_pages = zone_reclaimable_pages(zone);
 
                         /* No reclaimable slab or very low memory pressure */
-                        if (!shrink_slab(sc.nr_scanned, gfp_mask, lru_pages))
+                        if (!shrink_slab(&shrink, sc.nr_scanned, lru_pages))
                                 break;
 
                         /* Freed enough memory */