slub: use raw_cpu_inc for incrementing statistics
[pandora-kernel.git] / mm / slab_common.c
index 1ec3c61..f3cfccf 100644 (file)
@@ -29,8 +29,7 @@ DEFINE_MUTEX(slab_mutex);
 struct kmem_cache *kmem_cache;
 
 #ifdef CONFIG_DEBUG_VM
-static int kmem_cache_sanity_check(struct mem_cgroup *memcg, const char *name,
-                                  size_t size)
+static int kmem_cache_sanity_check(const char *name, size_t size)
 {
        struct kmem_cache *s = NULL;
 
@@ -57,13 +56,7 @@ static int kmem_cache_sanity_check(struct mem_cgroup *memcg, const char *name,
                }
 
 #if !defined(CONFIG_SLUB) || !defined(CONFIG_SLUB_DEBUG_ON)
-               /*
-                * For simplicity, we won't check this in the list of memcg
-                * caches. We have control over memcg naming, and if there
-                * aren't duplicates in the global list, there won't be any
-                * duplicates in the memcg lists as well.
-                */
-               if (!memcg && !strcmp(s->name, name)) {
+               if (!strcmp(s->name, name)) {
                        pr_err("%s (%s): Cache name already exists.\n",
                               __func__, name);
                        dump_stack();
@@ -77,8 +70,7 @@ static int kmem_cache_sanity_check(struct mem_cgroup *memcg, const char *name,
        return 0;
 }
 #else
-static inline int kmem_cache_sanity_check(struct mem_cgroup *memcg,
-                                         const char *name, size_t size)
+static inline int kmem_cache_sanity_check(const char *name, size_t size)
 {
        return 0;
 }
@@ -139,6 +131,46 @@ unsigned long calculate_alignment(unsigned long flags,
        return ALIGN(align, sizeof(void *));
 }
 
+static struct kmem_cache *
+do_kmem_cache_create(char *name, size_t object_size, size_t size, size_t align,
+                    unsigned long flags, void (*ctor)(void *),
+                    struct mem_cgroup *memcg, struct kmem_cache *root_cache)
+{
+       struct kmem_cache *s;
+       int err;
+
+       err = -ENOMEM;
+       s = kmem_cache_zalloc(kmem_cache, GFP_KERNEL);
+       if (!s)
+               goto out;
+
+       s->name = name;
+       s->object_size = object_size;
+       s->size = size;
+       s->align = align;
+       s->ctor = ctor;
+
+       err = memcg_alloc_cache_params(memcg, s, root_cache);
+       if (err)
+               goto out_free_cache;
+
+       err = __kmem_cache_create(s, flags);
+       if (err)
+               goto out_free_cache;
+
+       s->refcount = 1;
+       list_add(&s->list, &slab_caches);
+       memcg_register_cache(s);
+out:
+       if (err)
+               return ERR_PTR(err);
+       return s;
+
+out_free_cache:
+       memcg_free_cache_params(s);
+       kfree(s);
+       goto out;
+}
 
 /*
  * kmem_cache_create - Create a cache.
@@ -164,34 +196,21 @@ unsigned long calculate_alignment(unsigned long flags,
  * cacheline.  This can be beneficial if you're counting cycles as closely
  * as davem.
  */
-
 struct kmem_cache *
-kmem_cache_create_memcg(struct mem_cgroup *memcg, const char *name, size_t size,
-                       size_t align, unsigned long flags, void (*ctor)(void *),
-                       struct kmem_cache *parent_cache)
+kmem_cache_create(const char *name, size_t size, size_t align,
+                 unsigned long flags, void (*ctor)(void *))
 {
-       struct kmem_cache *s = NULL;
+       struct kmem_cache *s;
+       char *cache_name;
        int err;
 
        get_online_cpus();
        mutex_lock(&slab_mutex);
 
-       err = kmem_cache_sanity_check(memcg, name, size);
+       err = kmem_cache_sanity_check(name, size);
        if (err)
                goto out_unlock;
 
-       if (memcg) {
-               /*
-                * Since per-memcg caches are created asynchronously on first
-                * allocation (see memcg_kmem_get_cache()), several threads can
-                * try to create the same cache, but only one of them may
-                * succeed. Therefore if we get here and see the cache has
-                * already been created, we silently return NULL.
-                */
-               if (cache_from_memcg_idx(parent_cache, memcg_cache_id(memcg)))
-                       goto out_unlock;
-       }
-
        /*
         * Some allocators will constraint the set of valid flags to a subset
         * of all flags. We expect them to define CACHE_CREATE_MASK in this
@@ -200,50 +219,29 @@ kmem_cache_create_memcg(struct mem_cgroup *memcg, const char *name, size_t size,
         */
        flags &= CACHE_CREATE_MASK;
 
-       s = __kmem_cache_alias(memcg, name, size, align, flags, ctor);
+       s = __kmem_cache_alias(name, size, align, flags, ctor);
        if (s)
                goto out_unlock;
 
-       err = -ENOMEM;
-       s = kmem_cache_zalloc(kmem_cache, GFP_KERNEL);
-       if (!s)
+       cache_name = kstrdup(name, GFP_KERNEL);
+       if (!cache_name) {
+               err = -ENOMEM;
                goto out_unlock;
+       }
 
-       s->object_size = s->size = size;
-       s->align = calculate_alignment(flags, align, size);
-       s->ctor = ctor;
-
-       s->name = kstrdup(name, GFP_KERNEL);
-       if (!s->name)
-               goto out_free_cache;
-
-       err = memcg_alloc_cache_params(memcg, s, parent_cache);
-       if (err)
-               goto out_free_cache;
-
-       err = __kmem_cache_create(s, flags);
-       if (err)
-               goto out_free_cache;
-
-       s->refcount = 1;
-       list_add(&s->list, &slab_caches);
-       memcg_register_cache(s);
+       s = do_kmem_cache_create(cache_name, size, size,
+                                calculate_alignment(flags, align, size),
+                                flags, ctor, NULL, NULL);
+       if (IS_ERR(s)) {
+               err = PTR_ERR(s);
+               kfree(cache_name);
+       }
 
 out_unlock:
        mutex_unlock(&slab_mutex);
        put_online_cpus();
 
        if (err) {
-               /*
-                * There is no point in flooding logs with warnings or
-                * especially crashing the system if we fail to create a cache
-                * for a memcg. In this case we will be accounting the memcg
-                * allocation to the root cgroup until we succeed to create its
-                * own cache, but it isn't that critical.
-                */
-               if (!memcg)
-                       return NULL;
-
                if (flags & SLAB_PANIC)
                        panic("kmem_cache_create: Failed to create slab '%s'. Error %d\n",
                                name, err);
@@ -255,52 +253,112 @@ out_unlock:
                return NULL;
        }
        return s;
+}
+EXPORT_SYMBOL(kmem_cache_create);
 
-out_free_cache:
-       memcg_free_cache_params(s);
-       kfree(s->name);
-       kmem_cache_free(kmem_cache, s);
-       goto out_unlock;
+#ifdef CONFIG_MEMCG_KMEM
+/*
+ * kmem_cache_create_memcg - Create a cache for a memory cgroup.
+ * @memcg: The memory cgroup the new cache is for.
+ * @root_cache: The parent of the new cache.
+ *
+ * This function attempts to create a kmem cache that will serve allocation
+ * requests going from @memcg to @root_cache. The new cache inherits properties
+ * from its parent.
+ */
+void kmem_cache_create_memcg(struct mem_cgroup *memcg, struct kmem_cache *root_cache)
+{
+       struct kmem_cache *s;
+       char *cache_name;
+
+       get_online_cpus();
+       mutex_lock(&slab_mutex);
+
+       /*
+        * Since per-memcg caches are created asynchronously on first
+        * allocation (see memcg_kmem_get_cache()), several threads can try to
+        * create the same cache, but only one of them may succeed.
+        */
+       if (cache_from_memcg_idx(root_cache, memcg_cache_id(memcg)))
+               goto out_unlock;
+
+       cache_name = memcg_create_cache_name(memcg, root_cache);
+       if (!cache_name)
+               goto out_unlock;
+
+       s = do_kmem_cache_create(cache_name, root_cache->object_size,
+                                root_cache->size, root_cache->align,
+                                root_cache->flags, root_cache->ctor,
+                                memcg, root_cache);
+       if (IS_ERR(s)) {
+               kfree(cache_name);
+               goto out_unlock;
+       }
+
+       s->allocflags |= __GFP_KMEMCG;
+
+out_unlock:
+       mutex_unlock(&slab_mutex);
+       put_online_cpus();
 }
 
-struct kmem_cache *
-kmem_cache_create(const char *name, size_t size, size_t align,
-                 unsigned long flags, void (*ctor)(void *))
+static int kmem_cache_destroy_memcg_children(struct kmem_cache *s)
 {
-       return kmem_cache_create_memcg(NULL, name, size, align, flags, ctor, NULL);
+       int rc;
+
+       if (!s->memcg_params ||
+           !s->memcg_params->is_root_cache)
+               return 0;
+
+       mutex_unlock(&slab_mutex);
+       rc = __kmem_cache_destroy_memcg_children(s);
+       mutex_lock(&slab_mutex);
+
+       return rc;
 }
-EXPORT_SYMBOL(kmem_cache_create);
+#else
+static int kmem_cache_destroy_memcg_children(struct kmem_cache *s)
+{
+       return 0;
+}
+#endif /* CONFIG_MEMCG_KMEM */
 
 void kmem_cache_destroy(struct kmem_cache *s)
 {
-       /* Destroy all the children caches if we aren't a memcg cache */
-       kmem_cache_destroy_memcg_children(s);
-
        get_online_cpus();
        mutex_lock(&slab_mutex);
+
        s->refcount--;
-       if (!s->refcount) {
-               list_del(&s->list);
-
-               if (!__kmem_cache_shutdown(s)) {
-                       memcg_unregister_cache(s);
-                       mutex_unlock(&slab_mutex);
-                       if (s->flags & SLAB_DESTROY_BY_RCU)
-                               rcu_barrier();
-
-                       memcg_free_cache_params(s);
-                       kfree(s->name);
-                       kmem_cache_free(kmem_cache, s);
-               } else {
-                       list_add(&s->list, &slab_caches);
-                       mutex_unlock(&slab_mutex);
-                       printk(KERN_ERR "kmem_cache_destroy %s: Slab cache still has objects\n",
-                               s->name);
-                       dump_stack();
-               }
-       } else {
-               mutex_unlock(&slab_mutex);
+       if (s->refcount)
+               goto out_unlock;
+
+       if (kmem_cache_destroy_memcg_children(s) != 0)
+               goto out_unlock;
+
+       list_del(&s->list);
+       memcg_unregister_cache(s);
+
+       if (__kmem_cache_shutdown(s) != 0) {
+               list_add(&s->list, &slab_caches);
+               memcg_register_cache(s);
+               printk(KERN_ERR "kmem_cache_destroy %s: "
+                      "Slab cache still has objects\n", s->name);
+               dump_stack();
+               goto out_unlock;
        }
+
+       mutex_unlock(&slab_mutex);
+       if (s->flags & SLAB_DESTROY_BY_RCU)
+               rcu_barrier();
+
+       memcg_free_cache_params(s);
+       kfree(s->name);
+       kmem_cache_free(kmem_cache, s);
+       goto out_put_cpus;
+
+out_unlock:
+       mutex_unlock(&slab_mutex);
+out_put_cpus:
        put_online_cpus();
 }
 EXPORT_SYMBOL(kmem_cache_destroy);