]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - mm/vmscan.c
memory cgroup enhancements: fix zone handling in try_to_free_mem_cgroup_page
[karo-tx-linux.git] / mm / vmscan.c
index cb474cc996453006c0cc79430530ac1611b6facc..159e6c760d833fd3645a376fcc2790db9af1be5f 100644 (file)
@@ -37,6 +37,7 @@
 #include <linux/delay.h>
 #include <linux/kthread.h>
 #include <linux/freezer.h>
+#include <linux/memcontrol.h>
 
 #include <asm/tlbflush.h>
 #include <asm/div64.h>
@@ -68,6 +69,22 @@ struct scan_control {
        int all_unreclaimable;
 
        int order;
+
+       /*
+        * Pages that have (or should have) IO pending.  If we run into
+        * a lot of these, we're better off waiting a little for IO to
+        * finish rather than scanning more pages in the VM.
+        */
+       int nr_io_pages;
+
+       /* Which cgroup do we reclaim from */
+       struct mem_cgroup *mem_cgroup;
+
+       /* 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);
 };
 
 #define lru_to_page(_head) (list_entry((_head)->prev, struct page, lru))
@@ -141,7 +158,7 @@ EXPORT_SYMBOL(unregister_shrinker);
  * percentages of the lru and ageable caches.  This should balance the seeks
  * generated by these structures.
  *
- * If the vm encounted mapped pages on the LRU it increase the pressure on
+ * If the vm encountered mapped pages on the LRU it increase the pressure on
  * slab to avoid swapping.
  *
  * We do weird things to avoid (scanned*seeks*entries) overflowing 32 bits.
@@ -489,11 +506,13 @@ static unsigned long shrink_page_list(struct list_head *page_list,
                         */
                        if (sync_writeback == PAGEOUT_IO_SYNC && may_enter_fs)
                                wait_on_page_writeback(page);
-                       else
+                       else {
+                               sc->nr_io_pages++;
                                goto keep_locked;
+                       }
                }
 
-               referenced = page_referenced(page, 1);
+               referenced = page_referenced(page, 1, sc->mem_cgroup);
                /* In active use or really unfreeable?  Activate it. */
                if (sc->order <= PAGE_ALLOC_COSTLY_ORDER &&
                                        referenced && page_mapping_inuse(page))
@@ -529,8 +548,10 @@ static unsigned long shrink_page_list(struct list_head *page_list,
                if (PageDirty(page)) {
                        if (sc->order <= PAGE_ALLOC_COSTLY_ORDER && referenced)
                                goto keep_locked;
-                       if (!may_enter_fs)
+                       if (!may_enter_fs) {
+                               sc->nr_io_pages++;
                                goto keep_locked;
+                       }
                        if (!sc->may_writepage)
                                goto keep_locked;
 
@@ -541,8 +562,10 @@ static unsigned long shrink_page_list(struct list_head *page_list,
                        case PAGE_ACTIVATE:
                                goto activate_locked;
                        case PAGE_SUCCESS:
-                               if (PageWriteback(page) || PageDirty(page))
+                               if (PageWriteback(page) || PageDirty(page)) {
+                                       sc->nr_io_pages++;
                                        goto keep;
+                               }
                                /*
                                 * A synchronous write - probably a ramdisk.  Go
                                 * ahead and try to reclaim the page.
@@ -626,7 +649,7 @@ keep:
  *
  * returns 0 on success, -ve errno on failure.
  */
-static int __isolate_lru_page(struct page *page, int mode)
+int __isolate_lru_page(struct page *page, int mode)
 {
        int ret = -EINVAL;
 
@@ -760,6 +783,21 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
        return nr_taken;
 }
 
+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)
+{
+       if (active)
+               return isolate_lru_pages(nr, &z->active_list, dst,
+                                               scanned, order, mode);
+       else
+               return isolate_lru_pages(nr, &z->inactive_list, dst,
+                                               scanned, order, mode);
+}
+
 /*
  * clear_active_flags() is a helper for shrink_active_list(), clearing
  * any active bits from the pages in the list.
@@ -801,11 +839,11 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
                unsigned long nr_freed;
                unsigned long nr_active;
 
-               nr_taken = isolate_lru_pages(sc->swap_cluster_max,
-                            &zone->inactive_list,
+               nr_taken = sc->isolate_pages(sc->swap_cluster_max,
                             &page_list, &nr_scan, sc->order,
                             (sc->order > PAGE_ALLOC_COSTLY_ORDER)?
-                                            ISOLATE_BOTH : ISOLATE_INACTIVE);
+                                            ISOLATE_BOTH : ISOLATE_INACTIVE,
+                               zone, sc->mem_cgroup, 0);
                nr_active = clear_active_flags(&page_list);
                __count_vm_events(PGDEACTIVATE, nr_active);
 
@@ -1018,8 +1056,9 @@ force_reclaim_mapped:
 
        lru_add_drain();
        spin_lock_irq(&zone->lru_lock);
-       pgmoved = isolate_lru_pages(nr_pages, &zone->active_list,
-                           &l_hold, &pgscanned, sc->order, ISOLATE_ACTIVE);
+       pgmoved = sc->isolate_pages(nr_pages, &l_hold, &pgscanned, sc->order,
+                                       ISOLATE_ACTIVE, zone,
+                                       sc->mem_cgroup, 1);
        zone->pages_scanned += pgscanned;
        __mod_zone_page_state(zone, NR_ACTIVE, -pgmoved);
        spin_unlock_irq(&zone->lru_lock);
@@ -1031,7 +1070,7 @@ force_reclaim_mapped:
                if (page_mapped(page)) {
                        if (!reclaim_mapped ||
                            (total_swap_pages == 0 && PageAnon(page)) ||
-                           page_referenced(page, 0)) {
+                           page_referenced(page, 0, sc->mem_cgroup)) {
                                list_add(&page->lru, &l_active);
                                continue;
                        }
@@ -1051,6 +1090,7 @@ force_reclaim_mapped:
                ClearPageActive(page);
 
                list_move(&page->lru, &zone->inactive_list);
+               mem_cgroup_move_lists(page_get_page_cgroup(page), false);
                pgmoved++;
                if (!pagevec_add(&pvec, page)) {
                        __mod_zone_page_state(zone, NR_INACTIVE, pgmoved);
@@ -1079,6 +1119,7 @@ force_reclaim_mapped:
                SetPageLRU(page);
                VM_BUG_ON(!PageActive(page));
                list_move(&page->lru, &zone->active_list);
+               mem_cgroup_move_lists(page_get_page_cgroup(page), true);
                pgmoved++;
                if (!pagevec_add(&pvec, page)) {
                        __mod_zone_page_state(zone, NR_ACTIVE, pgmoved);
@@ -1206,7 +1247,8 @@ static unsigned long shrink_zones(int priority, struct zone **zones,
  * holds filesystem locks which prevent writeout this might not work, and the
  * allocation attempt will fail.
  */
-unsigned long try_to_free_pages(struct zone **zones, int order, gfp_t gfp_mask)
+static unsigned long do_try_to_free_pages(struct zone **zones, gfp_t gfp_mask,
+                                         struct scan_control *sc)
 {
        int priority;
        int ret = 0;
@@ -1215,14 +1257,6 @@ unsigned long try_to_free_pages(struct zone **zones, int order, gfp_t gfp_mask)
        struct reclaim_state *reclaim_state = current->reclaim_state;
        unsigned long lru_pages = 0;
        int i;
-       struct scan_control sc = {
-               .gfp_mask = gfp_mask,
-               .may_writepage = !laptop_mode,
-               .swap_cluster_max = SWAP_CLUSTER_MAX,
-               .may_swap = 1,
-               .swappiness = vm_swappiness,
-               .order = order,
-       };
 
        count_vm_event(ALLOCSTALL);
 
@@ -1237,17 +1271,23 @@ unsigned long try_to_free_pages(struct zone **zones, int order, gfp_t gfp_mask)
        }
 
        for (priority = DEF_PRIORITY; priority >= 0; priority--) {
-               sc.nr_scanned = 0;
+               sc->nr_scanned = 0;
+               sc->nr_io_pages = 0;
                if (!priority)
                        disable_swap_token();
-               nr_reclaimed += shrink_zones(priority, zones, &sc);
-               shrink_slab(sc.nr_scanned, gfp_mask, lru_pages);
+               nr_reclaimed += shrink_zones(priority, zones, sc);
+               /*
+                * Don't shrink slabs when reclaiming memory from
+                * over limit cgroups
+                */
+               if (sc->mem_cgroup == NULL)
+                       shrink_slab(sc->nr_scanned, gfp_mask, lru_pages);
                if (reclaim_state) {
                        nr_reclaimed += reclaim_state->reclaimed_slab;
                        reclaim_state->reclaimed_slab = 0;
                }
-               total_scanned += sc.nr_scanned;
-               if (nr_reclaimed >= sc.swap_cluster_max) {
+               total_scanned += sc->nr_scanned;
+               if (nr_reclaimed >= sc->swap_cluster_max) {
                        ret = 1;
                        goto out;
                }
@@ -1259,18 +1299,19 @@ unsigned long try_to_free_pages(struct zone **zones, int order, gfp_t gfp_mask)
                 * that's undesirable in laptop mode, where we *want* lumpy
                 * writeout.  So in laptop mode, write out the whole world.
                 */
-               if (total_scanned > sc.swap_cluster_max +
-                                       sc.swap_cluster_max / 2) {
+               if (total_scanned > sc->swap_cluster_max +
+                                       sc->swap_cluster_max / 2) {
                        wakeup_pdflush(laptop_mode ? 0 : total_scanned);
-                       sc.may_writepage = 1;
+                       sc->may_writepage = 1;
                }
 
                /* Take a nap, wait for some writeback to complete */
-               if (sc.nr_scanned && priority < DEF_PRIORITY - 2)
+               if (sc->nr_scanned && priority < DEF_PRIORITY - 2 &&
+                               sc->nr_io_pages > sc->swap_cluster_max)
                        congestion_wait(WRITE, HZ/10);
        }
        /* top priority shrink_caches still had more to do? don't OOM, then */
-       if (!sc.all_unreclaimable)
+       if (!sc->all_unreclaimable && sc->mem_cgroup == NULL)
                ret = 1;
 out:
        /*
@@ -1293,6 +1334,47 @@ out:
        return ret;
 }
 
+unsigned long try_to_free_pages(struct zone **zones, int order, gfp_t gfp_mask)
+{
+       struct scan_control sc = {
+               .gfp_mask = gfp_mask,
+               .may_writepage = !laptop_mode,
+               .swap_cluster_max = SWAP_CLUSTER_MAX,
+               .may_swap = 1,
+               .swappiness = vm_swappiness,
+               .order = order,
+               .mem_cgroup = NULL,
+               .isolate_pages = isolate_pages_global,
+       };
+
+       return do_try_to_free_pages(zones, gfp_mask, &sc);
+}
+
+#ifdef CONFIG_CGROUP_MEM_CONT
+
+unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont,
+                                               gfp_t gfp_mask)
+{
+       struct scan_control sc = {
+               .gfp_mask = gfp_mask,
+               .may_writepage = !laptop_mode,
+               .may_swap = 1,
+               .swap_cluster_max = SWAP_CLUSTER_MAX,
+               .swappiness = vm_swappiness,
+               .order = 0,
+               .mem_cgroup = mem_cont,
+               .isolate_pages = mem_cgroup_isolate_pages,
+       };
+       struct zone **zones;
+       int target_zone = gfp_zone(GFP_HIGHUSER_MOVABLE);
+
+       zones = NODE_DATA(numa_node_id())->node_zonelists[target_zone].zones;
+       if (do_try_to_free_pages(zones, sc.gfp_mask, &sc))
+               return 1;
+       return 0;
+}
+#endif
+
 /*
  * For kswapd, balance_pgdat() will work across all this node's zones until
  * they are all at pages_high.
@@ -1328,6 +1410,8 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order)
                .swap_cluster_max = SWAP_CLUSTER_MAX,
                .swappiness = vm_swappiness,
                .order = order,
+               .mem_cgroup = NULL,
+               .isolate_pages = isolate_pages_global,
        };
        /*
         * temp_priority is used to remember the scanning priority at which
@@ -1352,6 +1436,7 @@ loop_again:
                if (!priority)
                        disable_swap_token();
 
+               sc.nr_io_pages = 0;
                all_zones_ok = 1;
 
                /*
@@ -1444,7 +1529,8 @@ loop_again:
                 * OK, kswapd is getting into trouble.  Take a nap, then take
                 * another pass across the zones.
                 */
-               if (total_scanned && priority < DEF_PRIORITY - 2)
+               if (total_scanned && priority < DEF_PRIORITY - 2 &&
+                                       sc.nr_io_pages > sc.swap_cluster_max)
                        congestion_wait(WRITE, HZ/10);
 
                /*
@@ -1649,6 +1735,7 @@ unsigned long shrink_all_memory(unsigned long nr_pages)
                .swap_cluster_max = nr_pages,
                .may_writepage = 1,
                .swappiness = vm_swappiness,
+               .isolate_pages = isolate_pages_global,
        };
 
        current->reclaim_state = &reclaim_state;
@@ -1834,6 +1921,7 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
                                        SWAP_CLUSTER_MAX),
                .gfp_mask = gfp_mask,
                .swappiness = vm_swappiness,
+               .isolate_pages = isolate_pages_global,
        };
        unsigned long slab_reclaimable;