mm/slub: Use kmem_cache for the kmem_cache structure

Do not use kmalloc() but kmem_cache_alloc() for the allocation
of the kmem_cache structures in slub.
Reviewed-by: Glauber Costa <glommer@parallels.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

mm/slub.c

@@ -213,7 +213,7 @@ static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p)
 static inline void sysfs_slab_remove(struct kmem_cache *s)
 {
 	kfree(s->name);
-	kfree(s);
+	kmem_cache_free(kmem_cache, s);
 }
 
 #endif
@@ -3969,7 +3969,7 @@ struct kmem_cache *__kmem_cache_create(const char *name, size_t size,
 	if (!n)
 		return NULL;
 
-	s = kmalloc(kmem_size, GFP_KERNEL);
+	s = kmem_cache_alloc(kmem_cache, GFP_KERNEL);
 	if (s) {
 		if (kmem_cache_open(s, n,
 				size, align, flags, ctor)) {
@@ -3986,7 +3986,7 @@ struct kmem_cache *__kmem_cache_create(const char *name, size_t size,
 			list_del(&s->list);
 			kmem_cache_close(s);
 		}
-		kfree(s);
+		kmem_cache_free(kmem_cache, s);
 	}
 	kfree(n);
 	return NULL;
@@ -5224,7 +5224,7 @@ static void kmem_cache_release(struct kobject *kobj)
 	struct kmem_cache *s = to_slab(kobj);
 
 	kfree(s->name);
-	kfree(s);
+	kmem_cache_free(kmem_cache, s);
 }
 
 static const struct sysfs_ops slab_sysfs_ops = {