1 files changed, 26 insertions, 31 deletions

diff --git a/mm/slab.c b/mm/slab.c
index 37961d1f584f..568803f121a8 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -191,22 +191,6 @@ typedef unsigned int kmem_bufctl_t;
 #define SLAB_LIMIT      (((kmem_bufctl_t)(~0U))-3)
 
 /*
- * struct slab
- *
- * Manages the objs in a slab. Placed either at the beginning of mem allocated
- * for a slab, or allocated from an general cache.
- * Slabs are chained into three list: fully used, partial, fully free slabs.
- */
-struct slab {
-        struct list_head list;
-        unsigned long colouroff;
-        void *s_mem;            /* including colour offset */
-        unsigned int inuse;     /* num of objs active in slab */
-        kmem_bufctl_t free;
-        unsigned short nodeid;
-};
-
-/*
  * struct slab_rcu
  *
  * slab_destroy on a SLAB_DESTROY_BY_RCU cache uses this structure to
@@ -219,8 +203,6 @@ struct slab {
  *
  * rcu_read_lock before reading the address, then rcu_read_unlock after
  * taking the spinlock within the structure expected at that address.
- *
- * We assume struct slab_rcu can overlay struct slab when destroying.
  */
 struct slab_rcu {
         struct rcu_head head;
@@ -229,6 +211,27 @@ struct slab_rcu {
 };
 
 /*
+ * struct slab
+ *
+ * Manages the objs in a slab. Placed either at the beginning of mem allocated
+ * for a slab, or allocated from an general cache.
+ * Slabs are chained into three list: fully used, partial, fully free slabs.
+ */
+struct slab {
+        union {
+                struct {
+                        struct list_head list;
+                        unsigned long colouroff;
+                        void *s_mem;            /* including colour offset */
+                        unsigned int inuse;     /* num of objs active in slab */
+                        kmem_bufctl_t free;
+                        unsigned short nodeid;
+                };
+                struct slab_rcu __slab_cover_slab_rcu;
+        };
+};
+
+/*
  * struct array_cache
  *
  * Purpose:
@@ -1387,7 +1390,7 @@ static int __meminit slab_memory_callback(struct notifier_block *self,
                 break;
         }
 out:
-        return ret ? notifier_from_errno(ret) : NOTIFY_OK;
+        return notifier_from_errno(ret);
 }
 #endif /* CONFIG_NUMA && CONFIG_MEMORY_HOTPLUG */
 
@@ -2147,8 +2150,6 @@ static int __init_refok setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp)
  *
  * @name must be valid until the cache is destroyed. This implies that
  * the module calling this has to destroy the cache before getting unloaded.
- * Note that kmem_cache_name() is not guaranteed to return the same pointer,
- * therefore applications must manage it themselves.
  *
  * The flags are
  *
@@ -2288,8 +2289,8 @@ kmem_cache_create (const char *name, size_t size, size_t align,
         if (ralign < align) {
                 ralign = align;
         }
-        /* disable debug if not aligning with REDZONE_ALIGN */
-        if (ralign & (__alignof__(unsigned long long) - 1))
+        /* disable debug if necessary */
+        if (ralign > __alignof__(unsigned long long))
                 flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
         /*
          * 4) Store it.
@@ -2315,8 +2316,8 @@ kmem_cache_create (const char *name, size_t size, size_t align,
          */
         if (flags & SLAB_RED_ZONE) {
                 /* add space for red zone words */
-                cachep->obj_offset += align;
-                size += align + sizeof(unsigned long long);
+                cachep->obj_offset += sizeof(unsigned long long);
+                size += 2 * sizeof(unsigned long long);
         }
         if (flags & SLAB_STORE_USER) {
                 /* user store requires one word storage behind the end of
@@ -3840,12 +3841,6 @@ unsigned int kmem_cache_size(struct kmem_cache *cachep)
 }
 EXPORT_SYMBOL(kmem_cache_size);
 
-const char *kmem_cache_name(struct kmem_cache *cachep)
-{
-        return cachep->name;
-}
-EXPORT_SYMBOL_GPL(kmem_cache_name);
-
 /*
  * This initializes kmem_list3 or resizes various caches for all nodes.
  */