memcg: fix deadlock between lock_page_cgroup and mapping tree_lock

[sfrench/cifs-2.6.git] / mm / filemap.c

diff --git a/mm/filemap.c b/mm/filemap.c
index 379ff0bcbf6e88eb98e13550853fa215cbc25789..1b60f30cebfa88aa135c17173ec9ce831612fa90 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -121,7 +121,6 @@ void __remove_from_page_cache(struct page *page)
        mapping->nrpages--;
        __dec_zone_page_state(page, NR_FILE_PAGES);
        BUG_ON(page_mapped(page));
-       mem_cgroup_uncharge_cache_page(page);
 
        /*
         * Some filesystems seem to re-dirty the page even after
@@ -145,6 +144,7 @@ void remove_from_page_cache(struct page *page)
        spin_lock_irq(&mapping->tree_lock);
        __remove_from_page_cache(page);
        spin_unlock_irq(&mapping->tree_lock);
+       mem_cgroup_uncharge_cache_page(page);
 }
 
 static int sync_page(void *word)
@@ -476,13 +476,13 @@ int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
                if (likely(!error)) {
                        mapping->nrpages++;
                        __inc_zone_page_state(page, NR_FILE_PAGES);
+                       spin_unlock_irq(&mapping->tree_lock);
                } else {
                        page->mapping = NULL;
+                       spin_unlock_irq(&mapping->tree_lock);
                        mem_cgroup_uncharge_cache_page(page);
                        page_cache_release(page);
                }
-
-               spin_unlock_irq(&mapping->tree_lock);
                radix_tree_preload_end();
        } else
                mem_cgroup_uncharge_cache_page(page);