1 files changed, 60 insertions, 40 deletions

diff --git a/mm/slab.h b/mm/slab.h
index a535033f7e9..961a3fb1f5a 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -55,12 +55,12 @@ extern void create_boot_cache(struct kmem_cache *, const char *name,
 struct mem_cgroup;
 #ifdef CONFIG_SLUB
 struct kmem_cache *
-__kmem_cache_alias(struct mem_cgroup *memcg, const char *name, size_t size,
-		   size_t align, unsigned long flags, void (*ctor)(void *));
+__kmem_cache_alias(const char *name, size_t size, size_t align,
+		   unsigned long flags, void (*ctor)(void *));
 #else
 static inline struct kmem_cache *
-__kmem_cache_alias(struct mem_cgroup *memcg, const char *name, size_t size,
-		   size_t align, unsigned long flags, void (*ctor)(void *))
+__kmem_cache_alias(const char *name, size_t size, size_t align,
+		   unsigned long flags, void (*ctor)(void *))
 { return NULL; }
 #endif
 
@@ -91,6 +91,8 @@ __kmem_cache_alias(struct mem_cgroup *memcg, const char *name, size_t size,
 #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
 
 int __kmem_cache_shutdown(struct kmem_cache *);
+int __kmem_cache_shrink(struct kmem_cache *);
+void slab_kmem_cache_release(struct kmem_cache *);
 
 struct seq_file;
 struct file;
@@ -119,28 +121,6 @@ static inline bool is_root_cache(struct kmem_cache *s)
 	return !s->memcg_params || s->memcg_params->is_root_cache;
 }
 
-static inline bool cache_match_memcg(struct kmem_cache *cachep,
-				     struct mem_cgroup *memcg)
-{
-	return (is_root_cache(cachep) && !memcg) ||
-				(cachep->memcg_params->memcg == memcg);
-}
-
-static inline void memcg_bind_pages(struct kmem_cache *s, int order)
-{
-	if (!is_root_cache(s))
-		atomic_add(1 << order, &s->memcg_params->nr_pages);
-}
-
-static inline void memcg_release_pages(struct kmem_cache *s, int order)
-{
-	if (is_root_cache(s))
-		return;
-
-	if (atomic_sub_and_test((1 << order), &s->memcg_params->nr_pages))
-		mem_cgroup_destroy_cache(s);
-}
-
 static inline bool slab_equal_or_root(struct kmem_cache *s,
 					struct kmem_cache *p)
 {
@@ -160,11 +140,36 @@ static inline const char *cache_name(struct kmem_cache *s)
 	return s->name;
 }
 
-static inline struct kmem_cache *cache_from_memcg(struct kmem_cache *s, int idx)
+/*
+ * Note, we protect with RCU only the memcg_caches array, not per-memcg caches.
+ * That said the caller must assure the memcg's cache won't go away. Since once
+ * created a memcg's cache is destroyed only along with the root cache, it is
+ * true if we are going to allocate from the cache or hold a reference to the
+ * root cache by other means. Otherwise, we should hold either the slab_mutex
+ * or the memcg's slab_caches_mutex while calling this function and accessing
+ * the returned value.
+ */
+static inline struct kmem_cache *
+cache_from_memcg_idx(struct kmem_cache *s, int idx)
 {
+	struct kmem_cache *cachep;
+	struct memcg_cache_params *params;
+
 	if (!s->memcg_params)
 		return NULL;
-	return s->memcg_params->memcg_caches[idx];
+
+	rcu_read_lock();
+	params = rcu_dereference(s->memcg_params);
+	cachep = params->memcg_caches[idx];
+	rcu_read_unlock();
+
+	/*
+	 * Make sure we will access the up-to-date value. The code updating
+	 * memcg_caches issues a write barrier to match this (see
+	 * memcg_register_cache()).
+	 */
+	smp_read_barrier_depends();
+	return cachep;
 }
 
 static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
@@ -173,24 +178,29 @@ static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
 		return s;
 	return s->memcg_params->root_cache;
 }
-#else
-static inline bool is_root_cache(struct kmem_cache *s)
-{
-	return true;
-}
 
-static inline bool cache_match_memcg(struct kmem_cache *cachep,
-				     struct mem_cgroup *memcg)
+static __always_inline int memcg_charge_slab(struct kmem_cache *s,
+					     gfp_t gfp, int order)
 {
-	return true;
+	if (!memcg_kmem_enabled())
+		return 0;
+	if (is_root_cache(s))
+		return 0;
+	return __memcg_charge_slab(s, gfp, order);
 }
 
-static inline void memcg_bind_pages(struct kmem_cache *s, int order)
+static __always_inline void memcg_uncharge_slab(struct kmem_cache *s, int order)
 {
+	if (!memcg_kmem_enabled())
+		return;
+	if (is_root_cache(s))
+		return;
+	__memcg_uncharge_slab(s, order);
 }
-
-static inline void memcg_release_pages(struct kmem_cache *s, int order)
+#else
+static inline bool is_root_cache(struct kmem_cache *s)
 {
+	return true;
 }
 
 static inline bool slab_equal_or_root(struct kmem_cache *s,
@@ -204,7 +214,8 @@ static inline const char *cache_name(struct kmem_cache *s)
 	return s->name;
 }
 
-static inline struct kmem_cache *cache_from_memcg(struct kmem_cache *s, int idx)
+static inline struct kmem_cache *
+cache_from_memcg_idx(struct kmem_cache *s, int idx)
 {
 	return NULL;
 }
@@ -213,6 +224,15 @@ static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
 {
 	return s;
 }
+
+static inline int memcg_charge_slab(struct kmem_cache *s, gfp_t gfp, int order)
+{
+	return 0;
+}
+
+static inline void memcg_uncharge_slab(struct kmem_cache *s, int order)
+{
+}
 #endif
 
 static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)