slub: use __cmpxchg_double_slab() at interrupt disabled place

get_freelist(), unfreeze_partials() are only called with interrupt disabled,
so __cmpxchg_double_slab() is suitable.

Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

1 files changed, 9 insertions, 3 deletions

diff --git a/mm/slub.c b/mm/slub.c
index 348fed1643f4..4f406cd899b7 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1872,7 +1872,11 @@ redo:
         }
 }
 
-/* Unfreeze all the cpu partial slabs */
+/*
+ * Unfreeze all the cpu partial slabs.
+ *
+ * This function must be called with interrupt disabled.
+ */
 static void unfreeze_partials(struct kmem_cache *s)
 {
         struct kmem_cache_node *n = NULL;
@@ -1928,7 +1932,7 @@ static void unfreeze_partials(struct kmem_cache *s)
                                 l = m;
                         }
 
-                } while (!cmpxchg_double_slab(s, page,
+                } while (!__cmpxchg_double_slab(s, page,
                                 old.freelist, old.counters,
                                 new.freelist, new.counters,
                                 "unfreezing slab"));
@@ -2165,6 +2169,8 @@ static inline void *new_slab_objects(struct kmem_cache *s, gfp_t flags,
  * The page is still frozen if the return value is not NULL.
  *
  * If this function returns NULL then the page has been unfrozen.
+ *
+ * This function must be called with interrupt disabled.
  */
 static inline void *get_freelist(struct kmem_cache *s, struct page *page)
 {
@@ -2182,7 +2188,7 @@ static inline void *get_freelist(struct kmem_cache *s, struct page *page)
                 new.inuse = page->objects;
                 new.frozen = freelist != NULL;
 
-        } while (!cmpxchg_double_slab(s, page,
+        } while (!__cmpxchg_double_slab(s, page,
                 freelist, counters,
                 NULL, new.counters,
                 "get_freelist"));