memcg: better migration handling

[net-next-2.6.git] / mm / migrate.c

diff --git a/mm/migrate.c b/mm/migrate.c
index 376cceba82f98e7110520acc885f6bce0687482b..f6d7f8efd1a84b5fb1729013890ecaa3d6caa609 100644 (file)
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -358,6 +358,10 @@ static int migrate_page_move_mapping(struct address_space *mapping,
        __inc_zone_page_state(newpage, NR_FILE_PAGES);
 
        write_unlock_irq(&mapping->tree_lock);
+       if (!PageSwapCache(newpage)) {
+               mem_cgroup_uncharge_page(page);
+               mem_cgroup_getref(newpage);
+       }
 
        return 0;
 }
@@ -611,7 +615,6 @@ static int move_to_new_page(struct page *newpage, struct page *page)
                rc = fallback_migrate_page(mapping, newpage, page);
 
        if (!rc) {
-               mem_cgroup_page_migration(page, newpage);
                remove_migration_ptes(page, newpage);
        } else
                newpage->mapping = NULL;
@@ -641,6 +644,14 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
                /* page was freed from under us. So we are done. */
                goto move_newpage;
 
+       charge = mem_cgroup_prepare_migration(page, newpage);
+       if (charge == -ENOMEM) {
+               rc = -ENOMEM;
+               goto move_newpage;
+       }
+       /* prepare cgroup just returns 0 or -ENOMEM */
+       BUG_ON(charge);
+
        rc = -EAGAIN;
        if (TestSetPageLocked(page)) {
                if (!force)
@@ -692,19 +703,14 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
                goto rcu_unlock;
        }
 
-       charge = mem_cgroup_prepare_migration(page);
        /* Establish migration ptes or remove ptes */
        try_to_unmap(page, 1);
 
        if (!page_mapped(page))
                rc = move_to_new_page(newpage, page);
 
-       if (rc) {
+       if (rc)
                remove_migration_ptes(page, page);
-               if (charge)
-                       mem_cgroup_end_migration(page);
-       } else if (charge)
-               mem_cgroup_end_migration(newpage);
 rcu_unlock:
        if (rcu_locked)
                rcu_read_unlock();
@@ -725,6 +731,8 @@ unlock:
        }
 
 move_newpage:
+       if (!charge)
+               mem_cgroup_end_migration(newpage);
        /*
         * Move the new page to the LRU. If migration was not successful
         * then this will free the page.