include/asm-generic/kmap_types.h: add helpful reminder

[safe/jmp/linux-2.6] / mm / vmscan.c

diff --git a/mm/vmscan.c b/mm/vmscan.c
index cd4a5ed..915dceb 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -73,8 +73,6 @@ struct scan_control {
 
        int swappiness;
 
-       int all_unreclaimable;
-
        int order;
 
        /*
@@ -91,12 +89,6 @@ struct scan_control {
         * are scanned.
         */
        nodemask_t      *nodemask;
-
-       /* Pluggable isolate pages callback */
-       unsigned long (*isolate_pages)(unsigned long nr, struct list_head *dst,
-                       unsigned long *scanned, int order, int mode,
-                       struct zone *z, struct mem_cgroup *mem_cont,
-                       int active, int file);
 };
 
 #define lru_to_page(_head) (list_entry((_head)->prev, struct page, lru))
@@ -1012,7 +1004,6 @@ static unsigned long isolate_pages_global(unsigned long nr,
                                        struct list_head *dst,
                                        unsigned long *scanned, int order,
                                        int mode, struct zone *z,
-                                       struct mem_cgroup *mem_cont,
                                        int active, int file)
 {
        int lru = LRU_BASE;
@@ -1156,11 +1147,11 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
                unsigned long nr_anon;
                unsigned long nr_file;
 
-               nr_taken = sc->isolate_pages(SWAP_CLUSTER_MAX,
-                            &page_list, &nr_scan, sc->order, mode,
-                               zone, sc->mem_cgroup, 0, file);
-
                if (scanning_global_lru(sc)) {
+                       nr_taken = isolate_pages_global(SWAP_CLUSTER_MAX,
+                                                       &page_list, &nr_scan,
+                                                       sc->order, mode,
+                                                       zone, 0, file);
                        zone->pages_scanned += nr_scan;
                        if (current_is_kswapd())
                                __count_zone_vm_events(PGSCAN_KSWAPD, zone,
@@ -1168,6 +1159,16 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
                        else
                                __count_zone_vm_events(PGSCAN_DIRECT, zone,
                                                       nr_scan);
+               } else {
+                       nr_taken = mem_cgroup_isolate_pages(SWAP_CLUSTER_MAX,
+                                                       &page_list, &nr_scan,
+                                                       sc->order, mode,
+                                                       zone, sc->mem_cgroup,
+                                                       0, file);
+                       /*
+                        * mem_cgroup_isolate_pages() keeps track of
+                        * scanned pages on its own.
+                        */
                }
 
                if (nr_taken == 0)
@@ -1345,16 +1346,23 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone,
 
        lru_add_drain();
        spin_lock_irq(&zone->lru_lock);
-       nr_taken = sc->isolate_pages(nr_pages, &l_hold, &pgscanned, sc->order,
-                                       ISOLATE_ACTIVE, zone,
-                                       sc->mem_cgroup, 1, file);
-       /*
-        * zone->pages_scanned is used for detect zone's oom
-        * mem_cgroup remembers nr_scan by itself.
-        */
        if (scanning_global_lru(sc)) {
+               nr_taken = isolate_pages_global(nr_pages, &l_hold,
+                                               &pgscanned, sc->order,
+                                               ISOLATE_ACTIVE, zone,
+                                               1, file);
                zone->pages_scanned += pgscanned;
+       } else {
+               nr_taken = mem_cgroup_isolate_pages(nr_pages, &l_hold,
+                                               &pgscanned, sc->order,
+                                               ISOLATE_ACTIVE, zone,
+                                               sc->mem_cgroup, 1, file);
+               /*
+                * mem_cgroup_isolate_pages() keeps track of
+                * scanned pages on its own.
+                */
        }
+
        reclaim_stat->recent_scanned[file] += nr_taken;
 
        __count_zone_vm_events(PGREFILL, zone, pgscanned);
@@ -1716,14 +1724,14 @@ static void shrink_zone(int priority, struct zone *zone,
  * If a zone is deemed to be full of pinned pages then just give it a light
  * scan then give up on it.
  */
-static void shrink_zones(int priority, struct zonelist *zonelist,
+static int shrink_zones(int priority, struct zonelist *zonelist,
                                        struct scan_control *sc)
 {
        enum zone_type high_zoneidx = gfp_zone(sc->gfp_mask);
        struct zoneref *z;
        struct zone *zone;
+       int progress = 0;
 
-       sc->all_unreclaimable = 1;
        for_each_zone_zonelist_nodemask(zone, z, zonelist, high_zoneidx,
                                        sc->nodemask) {
                if (!populated_zone(zone))
@@ -1739,19 +1747,19 @@ static void shrink_zones(int priority, struct zonelist *zonelist,
 
                        if (zone->all_unreclaimable && priority != DEF_PRIORITY)
                                continue;       /* Let kswapd poll it */
-                       sc->all_unreclaimable = 0;
                } else {
                        /*
                         * Ignore cpuset limitation here. We just want to reduce
                         * # of used pages by us regardless of memory shortage.
                         */
-                       sc->all_unreclaimable = 0;
                        mem_cgroup_note_reclaim_priority(sc->mem_cgroup,
                                                        priority);
                }
 
                shrink_zone(priority, zone, sc);
+               progress = 1;
        }
+       return progress;
 }
 
 /*
@@ -1805,7 +1813,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
                sc->nr_scanned = 0;
                if (!priority)
                        disable_swap_token();
-               shrink_zones(priority, zonelist, sc);
+               ret = shrink_zones(priority, zonelist, sc);
                /*
                 * Don't shrink slabs when reclaiming memory from
                 * over limit cgroups
@@ -1842,7 +1850,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
                        congestion_wait(BLK_RW_ASYNC, HZ/10);
        }
        /* top priority shrink_zones still had more to do? don't OOM, then */
-       if (!sc->all_unreclaimable && scanning_global_lru(sc))
+       if (ret && scanning_global_lru(sc))
                ret = sc->nr_reclaimed;
 out:
        /*
@@ -1884,7 +1892,6 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
                .swappiness = vm_swappiness,
                .order = order,
                .mem_cgroup = NULL,
-               .isolate_pages = isolate_pages_global,
                .nodemask = nodemask,
        };
 
@@ -1905,7 +1912,6 @@ unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem,
                .swappiness = swappiness,
                .order = 0,
                .mem_cgroup = mem,
-               .isolate_pages = mem_cgroup_isolate_pages,
        };
        nodemask_t nm  = nodemask_of_node(nid);
 
@@ -1939,7 +1945,6 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont,
                .swappiness = swappiness,
                .order = 0,
                .mem_cgroup = mem_cont,
-               .isolate_pages = mem_cgroup_isolate_pages,
                .nodemask = NULL, /* we don't care the placement */
        };
 
@@ -2017,7 +2022,6 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order)
                .swappiness = vm_swappiness,
                .order = order,
                .mem_cgroup = NULL,
-               .isolate_pages = isolate_pages_global,
        };
        /*
         * temp_priority is used to remember the scanning priority at which
@@ -2396,7 +2400,6 @@ unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
                .hibernation_mode = 1,
                .swappiness = vm_swappiness,
                .order = 0,
-               .isolate_pages = isolate_pages_global,
        };
        struct zonelist * zonelist = node_zonelist(numa_node_id(), sc.gfp_mask);
        struct task_struct *p = current;
@@ -2581,7 +2584,6 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
                .gfp_mask = gfp_mask,
                .swappiness = vm_swappiness,
                .order = order,
-               .isolate_pages = isolate_pages_global,
        };
        unsigned long slab_reclaimable;