1 files changed, 66 insertions, 2 deletions

diff --git a/mm/slab.h b/mm/slab.h
index 9057b8056b07..b2b01694dc43 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -30,6 +30,69 @@ struct kmem_cache {
 	struct list_head list;	/* List of all slab caches on the system */
 };
 
+#else /* !CONFIG_SLOB */
+
+struct memcg_cache_array {
+	struct rcu_head rcu;
+	struct kmem_cache *entries[0];
+};
+
+/*
+ * This is the main placeholder for memcg-related information in kmem caches.
+ * Both the root cache and the child caches will have it. For the root cache,
+ * this will hold a dynamically allocated array large enough to hold
+ * information about the currently limited memcgs in the system. To allow the
+ * array to be accessed without taking any locks, on relocation we free the old
+ * version only after a grace period.
+ *
+ * Root and child caches hold different metadata.
+ *
+ * @root_cache:	Common to root and child caches.  NULL for root, pointer to
+ *		the root cache for children.
+ *
+ * The following fields are specific to root caches.
+ *
+ * @memcg_caches: kmemcg ID indexed table of child caches.  This table is
+ *		used to index child cachces during allocation and cleared
+ *		early during shutdown.
+ *
+ * @root_caches_node: List node for slab_root_caches list.
+ *
+ * @children:	List of all child caches.  While the child caches are also
+ *		reachable through @memcg_caches, a child cache remains on
+ *		this list until it is actually destroyed.
+ *
+ * The following fields are specific to child caches.
+ *
+ * @memcg:	Pointer to the memcg this cache belongs to.
+ *
+ * @children_node: List node for @root_cache->children list.
+ *
+ * @kmem_caches_node: List node for @memcg->kmem_caches list.
+ */
+struct memcg_cache_params {
+	struct kmem_cache *root_cache;
+	union {
+		struct {
+			struct memcg_cache_array __rcu *memcg_caches;
+			struct list_head __root_caches_node;
+			struct list_head children;
+			bool dying;
+		};
+		struct {
+			struct mem_cgroup *memcg;
+			struct list_head children_node;
+			struct list_head kmem_caches_node;
+			struct percpu_ref refcnt;
+
+			void (*work_fn)(struct kmem_cache *);
+			union {
+				struct rcu_head rcu_head;
+				struct work_struct work;
+			};
+		};
+	};
+};
 #endif /* CONFIG_SLOB */
 
 #ifdef CONFIG_SLAB
@@ -174,6 +237,7 @@ int __kmem_cache_shrink(struct kmem_cache *);
 void __kmemcg_cache_deactivate(struct kmem_cache *s);
 void __kmemcg_cache_deactivate_after_rcu(struct kmem_cache *s);
 void slab_kmem_cache_release(struct kmem_cache *);
+void kmem_cache_shrink_all(struct kmem_cache *s);
 
 struct seq_file;
 struct file;
@@ -259,8 +323,8 @@ static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
  * Expects a pointer to a slab page. Please note, that PageSlab() check
  * isn't sufficient, as it returns true also for tail compound slab pages,
  * which do not have slab_cache pointer set.
- * So this function assumes that the page can pass PageHead() and PageSlab()
- * checks.
+ * So this function assumes that the page can pass PageSlab() && !PageTail()
+ * check.
  *
  * The kmem_cache can be reparented asynchronously. The caller must ensure
  * the memcg lifetime, e.g. by taking rcu_read_lock() or cgroup_mutex.