Merge branch 'akpm-current/current'

1 files changed, 109 insertions, 137 deletions

diff --git a/mm/slub.c b/mm/slub.c
index 8c24a23fdafa..3b2bae91811c 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -233,11 +233,6 @@ static inline void stat(const struct kmem_cache *s, enum stat_item si)
  * 			Core slab cache functions
  *******************************************************************/
 
-static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
-{
-	return s->node[node];
-}
-
 /* Verify that a pointer has an address that is valid within a slab page */
 static inline int check_valid_pointer(struct kmem_cache *s,
 				struct page *page, const void *object)
@@ -288,6 +283,10 @@ static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp)
 	for (__p = (__addr); __p < (__addr) + (__objects) * (__s)->size;\
 			__p += (__s)->size)
 
+#define for_each_object_idx(__p, __idx, __s, __addr, __objects) \
+	for (__p = (__addr), __idx = 1; __idx <= __objects;\
+			__p += (__s)->size, __idx++)
+
 /* Determine object index from a given position */
 static inline int slab_index(void *p, struct kmem_cache *s, void *addr)
 {
@@ -945,60 +944,6 @@ static void trace(struct kmem_cache *s, struct page *page, void *object,
 }
 
 /*
- * Hooks for other subsystems that check memory allocations. In a typical
- * production configuration these hooks all should produce no code at all.
- */
-static inline void kmalloc_large_node_hook(void *ptr, size_t size, gfp_t flags)
-{
-	kmemleak_alloc(ptr, size, 1, flags);
-}
-
-static inline void kfree_hook(const void *x)
-{
-	kmemleak_free(x);
-}
-
-static inline int slab_pre_alloc_hook(struct kmem_cache *s, gfp_t flags)
-{
-	flags &= gfp_allowed_mask;
-	lockdep_trace_alloc(flags);
-	might_sleep_if(flags & __GFP_WAIT);
-
-	return should_failslab(s->object_size, flags, s->flags);
-}
-
-static inline void slab_post_alloc_hook(struct kmem_cache *s,
-					gfp_t flags, void *object)
-{
-	flags &= gfp_allowed_mask;
-	kmemcheck_slab_alloc(s, flags, object, slab_ksize(s));
-	kmemleak_alloc_recursive(object, s->object_size, 1, s->flags, flags);
-}
-
-static inline void slab_free_hook(struct kmem_cache *s, void *x)
-{
-	kmemleak_free_recursive(x, s->flags);
-
-	/*
-	 * Trouble is that we may no longer disable interrupts in the fast path
-	 * So in order to make the debug calls that expect irqs to be
-	 * disabled we need to disable interrupts temporarily.
-	 */
-#if defined(CONFIG_KMEMCHECK) || defined(CONFIG_LOCKDEP)
-	{
-		unsigned long flags;
-
-		local_irq_save(flags);
-		kmemcheck_slab_free(s, x, s->object_size);
-		debug_check_no_locks_freed(x, s->object_size);
-		local_irq_restore(flags);
-	}
-#endif
-	if (!(s->flags & SLAB_DEBUG_OBJECTS))
-		debug_check_no_obj_freed(x, s->object_size);
-}
-
-/*
  * Tracking of fully allocated slabs for debugging purposes.
  */
 static void add_full(struct kmem_cache *s,
@@ -1282,6 +1227,12 @@ static inline void inc_slabs_node(struct kmem_cache *s, int node,
 static inline void dec_slabs_node(struct kmem_cache *s, int node,
 							int objects) {}
 
+#endif /* CONFIG_SLUB_DEBUG */
+
+/*
+ * Hooks for other subsystems that check memory allocations. In a typical
+ * production configuration these hooks all should produce no code at all.
+ */
 static inline void kmalloc_large_node_hook(void *ptr, size_t size, gfp_t flags)
 {
 	kmemleak_alloc(ptr, size, 1, flags);
@@ -1293,21 +1244,44 @@ static inline void kfree_hook(const void *x)
 }
 
 static inline int slab_pre_alloc_hook(struct kmem_cache *s, gfp_t flags)
-							{ return 0; }
+{
+	flags &= gfp_allowed_mask;
+	lockdep_trace_alloc(flags);
+	might_sleep_if(flags & __GFP_WAIT);
+
+	return should_failslab(s->object_size, flags, s->flags);
+}
 
-static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
-		void *object)
+static inline void slab_post_alloc_hook(struct kmem_cache *s,
+					gfp_t flags, void *object)
 {
-	kmemleak_alloc_recursive(object, s->object_size, 1, s->flags,
-		flags & gfp_allowed_mask);
+	flags &= gfp_allowed_mask;
+	kmemcheck_slab_alloc(s, flags, object, slab_ksize(s));
+	kmemleak_alloc_recursive(object, s->object_size, 1, s->flags, flags);
 }
 
 static inline void slab_free_hook(struct kmem_cache *s, void *x)
 {
 	kmemleak_free_recursive(x, s->flags);
-}
 
-#endif /* CONFIG_SLUB_DEBUG */
+	/*
+	 * Trouble is that we may no longer disable interrupts in the fast path
+	 * So in order to make the debug calls that expect irqs to be
+	 * disabled we need to disable interrupts temporarily.
+	 */
+#if defined(CONFIG_KMEMCHECK) || defined(CONFIG_LOCKDEP)
+	{
+		unsigned long flags;
+
+		local_irq_save(flags);
+		kmemcheck_slab_free(s, x, s->object_size);
+		debug_check_no_locks_freed(x, s->object_size);
+		local_irq_restore(flags);
+	}
+#endif
+	if (!(s->flags & SLAB_DEBUG_OBJECTS))
+		debug_check_no_obj_freed(x, s->object_size);
+}
 
 /*
  * Slab allocation and freeing
@@ -1409,9 +1383,9 @@ static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
 {
 	struct page *page;
 	void *start;
-	void *last;
 	void *p;
 	int order;
+	int idx;
 
 	BUG_ON(flags & GFP_SLAB_BUG_MASK);
 
@@ -1432,14 +1406,13 @@ static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
 	if (unlikely(s->flags & SLAB_POISON))
 		memset(start, POISON_INUSE, PAGE_SIZE << order);
 
-	last = start;
-	for_each_object(p, s, start, page->objects) {
-		setup_object(s, page, last);
-		set_freepointer(s, last, p);
-		last = p;
+	for_each_object_idx(p, idx, s, start, page->objects) {
+		setup_object(s, page, p);
+		if (likely(idx < page->objects))
+			set_freepointer(s, p, p + s->size);
+		else
+			set_freepointer(s, p, NULL);
 	}
-	setup_object(s, page, last);
-	set_freepointer(s, last, NULL);
 
 	page->freelist = start;
 	page->inuse = page->objects;
@@ -2064,6 +2037,14 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain)
 
 	} while (this_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page)
 								!= oldpage);
+
+	if (memcg_cache_dead(s)) {
+		unsigned long flags;
+
+		local_irq_save(flags);
+		unfreeze_partials(s, this_cpu_ptr(s->cpu_slab));
+		local_irq_restore(flags);
+	}
 #endif
 }
 
@@ -2162,6 +2143,7 @@ slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid)
 	static DEFINE_RATELIMIT_STATE(slub_oom_rs, DEFAULT_RATELIMIT_INTERVAL,
 				      DEFAULT_RATELIMIT_BURST);
 	int node;
+	struct kmem_cache_node *n;
 
 	if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs))
 		return;
@@ -2176,15 +2158,11 @@ slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid)
 		pr_warn("  %s debugging increased min order, use slub_debug=O to disable.\n",
 			s->name);
 
-	for_each_online_node(node) {
-		struct kmem_cache_node *n = get_node(s, node);
+	for_each_kmem_cache_node(s, node, n) {
 		unsigned long nr_slabs;
 		unsigned long nr_objs;
 		unsigned long nr_free;
 
-		if (!n)
-			continue;
-
 		nr_free  = count_partial(n, count_free);
 		nr_slabs = node_nr_slabs(n);
 		nr_objs  = node_nr_objs(n);
@@ -2673,18 +2651,17 @@ static __always_inline void slab_free(struct kmem_cache *s,
 
 	slab_free_hook(s, x);
 
-redo:
 	/*
-	 * Determine the currently cpus per cpu slab.
-	 * The cpu may change afterward. However that does not matter since
-	 * data is retrieved via this pointer. If we are on the same cpu
-	 * during the cmpxchg then the free will succedd.
+	 * We could make this function fully preemptable, but then we wouldn't
+	 * have a method to wait for all currently executing kfree's to finish,
+	 * which is necessary to avoid use-after-free on per memcg cache
+	 * destruction.
 	 */
 	preempt_disable();
+redo:
 	c = this_cpu_ptr(s->cpu_slab);
 
 	tid = c->tid;
-	preempt_enable();
 
 	if (likely(page == c->page)) {
 		set_freepointer(s, object, c->freelist);
@@ -2701,6 +2678,7 @@ redo:
 	} else
 		__slab_free(s, page, x, addr);
 
+	preempt_enable();
 }
 
 void kmem_cache_free(struct kmem_cache *s, void *x)
@@ -2928,13 +2906,10 @@ static void early_kmem_cache_node_alloc(int node)
 static void free_kmem_cache_nodes(struct kmem_cache *s)
 {
 	int node;
+	struct kmem_cache_node *n;
 
-	for_each_node_state(node, N_NORMAL_MEMORY) {
-		struct kmem_cache_node *n = s->node[node];
-
-		if (n)
-			kmem_cache_free(kmem_cache_node, n);
-
+	for_each_kmem_cache_node(s, node, n) {
+		kmem_cache_free(kmem_cache_node, n);
 		s->node[node] = NULL;
 	}
 }
@@ -3224,12 +3199,11 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
 static inline int kmem_cache_close(struct kmem_cache *s)
 {
 	int node;
+	struct kmem_cache_node *n;
 
 	flush_all(s);
 	/* Attempt to free all objects */
-	for_each_node_state(node, N_NORMAL_MEMORY) {
-		struct kmem_cache_node *n = get_node(s, node);
-
+	for_each_kmem_cache_node(s, node, n) {
 		free_partial(s, n);
 		if (n->nr_partial || slabs_node(s, node))
 			return 1;
@@ -3406,20 +3380,26 @@ int __kmem_cache_shrink(struct kmem_cache *s)
 	struct page *page;
 	struct page *t;
 	int objects = oo_objects(s->max);
+	struct list_head empty_slabs;
 	struct list_head *slabs_by_inuse =
 		kmalloc(sizeof(struct list_head) * objects, GFP_KERNEL);
 	unsigned long flags;
 
-	if (!slabs_by_inuse)
-		return -ENOMEM;
+	if (memcg_cache_dead(s))
+		s->min_partial = 0;
 
-	flush_all(s);
-	for_each_node_state(node, N_NORMAL_MEMORY) {
-		n = get_node(s, node);
-
-		if (!n->nr_partial)
-			continue;
+	if (!slabs_by_inuse) {
+		/*
+		 * Do not fail shrinking empty slabs if allocation of the
+		 * temporary array failed. Just skip the slab placement
+		 * optimization then.
+		 */
+		slabs_by_inuse = &empty_slabs;
+		objects = 1;
+	}
 
+	flush_all(s);
+	for_each_kmem_cache_node(s, node, n) {
 		for (i = 0; i < objects; i++)
 			INIT_LIST_HEAD(slabs_by_inuse + i);
 
@@ -3432,7 +3412,9 @@ int __kmem_cache_shrink(struct kmem_cache *s)
 		 * list_lock. page->inuse here is the upper limit.
 		 */
 		list_for_each_entry_safe(page, t, &n->partial, lru) {
-			list_move(&page->lru, slabs_by_inuse + page->inuse);
+			if (page->inuse < objects)
+				list_move(&page->lru,
+					  slabs_by_inuse + page->inuse);
 			if (!page->inuse)
 				n->nr_partial--;
 		}
@@ -3451,7 +3433,8 @@ int __kmem_cache_shrink(struct kmem_cache *s)
 			discard_slab(s, page);
 	}
 
-	kfree(slabs_by_inuse);
+	if (slabs_by_inuse != &empty_slabs)
+		kfree(slabs_by_inuse);
 	return 0;
 }
 
@@ -3588,6 +3571,7 @@ static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache)
 {
 	int node;
 	struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT);
+	struct kmem_cache_node *n;
 
 	memcpy(s, static_cache, kmem_cache->object_size);
 
@@ -3597,19 +3581,16 @@ static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache)
 	 * IPIs around.
 	 */
 	__flush_cpu_slab(s, smp_processor_id());
-	for_each_node_state(node, N_NORMAL_MEMORY) {
-		struct kmem_cache_node *n = get_node(s, node);
+	for_each_kmem_cache_node(s, node, n) {
 		struct page *p;
 
-		if (n) {
-			list_for_each_entry(p, &n->partial, lru)
-				p->slab_cache = s;
+		list_for_each_entry(p, &n->partial, lru)
+			p->slab_cache = s;
 
 #ifdef CONFIG_SLUB_DEBUG
-			list_for_each_entry(p, &n->full, lru)
-				p->slab_cache = s;
+		list_for_each_entry(p, &n->full, lru)
+			p->slab_cache = s;
 #endif
-		}
 	}
 	list_add(&s->list, &slab_caches);
 	return s;
@@ -3962,16 +3943,14 @@ static long validate_slab_cache(struct kmem_cache *s)
 	unsigned long count = 0;
 	unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
 				sizeof(unsigned long), GFP_KERNEL);
+	struct kmem_cache_node *n;
 
 	if (!map)
 		return -ENOMEM;
 
 	flush_all(s);
-	for_each_node_state(node, N_NORMAL_MEMORY) {
-		struct kmem_cache_node *n = get_node(s, node);
-
+	for_each_kmem_cache_node(s, node, n)
 		count += validate_slab_node(s, n, map);
-	}
 	kfree(map);
 	return count;
 }
@@ -4125,6 +4104,7 @@ static int list_locations(struct kmem_cache *s, char *buf,
 	int node;
 	unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
 				     sizeof(unsigned long), GFP_KERNEL);
+	struct kmem_cache_node *n;
 
 	if (!map || !alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location),
 				     GFP_TEMPORARY)) {
@@ -4134,8 +4114,7 @@ static int list_locations(struct kmem_cache *s, char *buf,
 	/* Push back cpu slabs */
 	flush_all(s);
 
-	for_each_node_state(node, N_NORMAL_MEMORY) {
-		struct kmem_cache_node *n = get_node(s, node);
+	for_each_kmem_cache_node(s, node, n) {
 		unsigned long flags;
 		struct page *page;
 
@@ -4207,7 +4186,7 @@ static int list_locations(struct kmem_cache *s, char *buf,
 #endif
 
 #ifdef SLUB_RESILIENCY_TEST
-static void resiliency_test(void)
+static void __init resiliency_test(void)
 {
 	u8 *p;
 
@@ -4334,8 +4313,9 @@ static ssize_t show_slab_objects(struct kmem_cache *s,
 	get_online_mems();
 #ifdef CONFIG_SLUB_DEBUG
 	if (flags & SO_ALL) {
-		for_each_node_state(node, N_NORMAL_MEMORY) {
-			struct kmem_cache_node *n = get_node(s, node);
+		struct kmem_cache_node *n;
+
+		for_each_kmem_cache_node(s, node, n) {
 
 			if (flags & SO_TOTAL)
 				x = atomic_long_read(&n->total_objects);
@@ -4351,9 +4331,9 @@ static ssize_t show_slab_objects(struct kmem_cache *s,
 	} else
 #endif
 	if (flags & SO_PARTIAL) {
-		for_each_node_state(node, N_NORMAL_MEMORY) {
-			struct kmem_cache_node *n = get_node(s, node);
+		struct kmem_cache_node *n;
 
+		for_each_kmem_cache_node(s, node, n) {
 			if (flags & SO_TOTAL)
 				x = count_partial(n, count_total);
 			else if (flags & SO_OBJECTS)
@@ -4366,7 +4346,7 @@ static ssize_t show_slab_objects(struct kmem_cache *s,
 	}
 	x = sprintf(buf, "%lu", total);
 #ifdef CONFIG_NUMA
-	for_each_node_state(node, N_NORMAL_MEMORY)
+	for (node = 0; node < nr_node_ids; node++)
 		if (nodes[node])
 			x += sprintf(buf + x, " N%d=%lu",
 					node, nodes[node]);
@@ -4380,16 +4360,12 @@ static ssize_t show_slab_objects(struct kmem_cache *s,
 static int any_slab_objects(struct kmem_cache *s)
 {
 	int node;
+	struct kmem_cache_node *n;
 
-	for_each_online_node(node) {
-		struct kmem_cache_node *n = get_node(s, node);
-
-		if (!n)
-			continue;
-
+	for_each_kmem_cache_node(s, node, n)
 		if (atomic_long_read(&n->total_objects))
 			return 1;
-	}
+
 	return 0;
 }
 #endif
@@ -5344,13 +5320,9 @@ void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo)
 	unsigned long nr_objs = 0;
 	unsigned long nr_free = 0;
 	int node;
+	struct kmem_cache_node *n;
 
-	for_each_online_node(node) {
-		struct kmem_cache_node *n = get_node(s, node);
-
-		if (!n)
-			continue;
-
+	for_each_kmem_cache_node(s, node, n) {
 		nr_slabs += node_nr_slabs(n);
 		nr_objs += node_nr_objs(n);
 		nr_free += count_partial(n, count_free);