Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
  slab, kmemleak: pass the correct pointer to kmemleak_erase()
  slab, kmemleak: stop calling kmemleak_erase() unconditionally
  SLAB: Fix unlikely() annotation in __cache_alloc_node()
  SLAB: Fix lockdep annotations for CPU hotplug
  SLUB: Fix __GFP_ZERO unlikely() annotation
  slub: allow stats to be cleared

mm/slab.c

@@ -604,6 +604,26 @@ static struct kmem_cache cache_cache = {
 
 #define BAD_ALIEN_MAGIC 0x01020304ul
 
+/*
+ * chicken and egg problem: delay the per-cpu array allocation
+ * until the general caches are up.
+ */
+static enum {
+	NONE,
+	PARTIAL_AC,
+	PARTIAL_L3,
+	EARLY,
+	FULL
+} g_cpucache_up;
+
+/*
+ * used by boot code to determine if it can use slab based allocator
+ */
+int slab_is_available(void)
+{
+	return g_cpucache_up >= EARLY;
+}
+
 #ifdef CONFIG_LOCKDEP
 
 /*
@@ -620,19 +640,21 @@ static struct kmem_cache cache_cache = {
 static struct lock_class_key on_slab_l3_key;
 static struct lock_class_key on_slab_alc_key;
 
-static inline void init_lock_keys(void)
-
+static void init_node_lock_keys(int q)
 {
-	int q;
 	struct cache_sizes *s = malloc_sizes;
 
-	while (s->cs_size != ULONG_MAX) {
-		for_each_node(q) {
+	if (g_cpucache_up != FULL)
+		return;
+
+	for (s = malloc_sizes; s->cs_size != ULONG_MAX; s++) {
 		struct array_cache **alc;
+		struct kmem_list3 *l3;
 		int r;
-			struct kmem_list3 *l3 = s->cs_cachep->nodelists[q];
+
+		l3 = s->cs_cachep->nodelists[q];
 		if (!l3 || OFF_SLAB(s->cs_cachep))
-				continue;
+			return;
 		lockdep_set_class(&l3->list_lock, &on_slab_l3_key);
 		alc = l3->alien;
 		/*
@@ -643,17 +665,27 @@ static inline void init_lock_keys(void)
 		 * for alloc_alien_cache,
 		 */
 		if (!alc || (unsigned long)alc == BAD_ALIEN_MAGIC)
-				continue;
+			return;
 		for_each_node(r) {
 			if (alc[r])
 				lockdep_set_class(&alc[r]->lock,
 					&on_slab_alc_key);
 		}
 	}
-		s++;
-	}
+}
+
+static inline void init_lock_keys(void)
+{
+	int node;
+
+	for_each_node(node)
+		init_node_lock_keys(node);
 }
 #else
+static void init_node_lock_keys(int q)
+{
+}
+
 static inline void init_lock_keys(void)
 {
 }
@@ -665,26 +697,6 @@ static inline void init_lock_keys(void)
 static DEFINE_MUTEX(cache_chain_mutex);
 static struct list_head cache_chain;
 
-/*
- * chicken and egg problem: delay the per-cpu array allocation
- * until the general caches are up.
- */
-static enum {
-	NONE,
-	PARTIAL_AC,
-	PARTIAL_L3,
-	EARLY,
-	FULL
-} g_cpucache_up;
-
-/*
- * used by boot code to determine if it can use slab based allocator
- */
-int slab_is_available(void)
-{
-	return g_cpucache_up >= EARLY;
-}
-
 static DEFINE_PER_CPU(struct delayed_work, reap_work);
 
 static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep)
@@ -1254,6 +1266,8 @@ static int __cpuinit cpuup_prepare(long cpu)
 		kfree(shared);
 		free_alien_cache(alien);
 	}
+	init_node_lock_keys(node);
+
 	return 0;
 bad:
 	cpuup_canceled(cpu);
@@ -3103,12 +3117,18 @@ static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags)
 	} else {
 		STATS_INC_ALLOCMISS(cachep);
 		objp = cache_alloc_refill(cachep, flags);
+		/*
+		 * the 'ac' may be updated by cache_alloc_refill(),
+		 * and kmemleak_erase() requires its correct value.
+		 */
+		ac = cpu_cache_get(cachep);
 	}
 	/*
 	 * To avoid a false negative, if an object that is in one of the
 	 * per-CPU caches is leaked, we need to make sure kmemleak doesn't
 	 * treat the array pointers as a reference to the object.
 	 */
+	if (objp)
 		kmemleak_erase(&ac->entry[ac->avail]);
 	return objp;
 }
@@ -3306,7 +3326,7 @@ __cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid,
 	cache_alloc_debugcheck_before(cachep, flags);
 	local_irq_save(save_flags);
 
-	if (unlikely(nodeid == -1))
+	if (nodeid == -1)
 		nodeid = numa_node_id();
 
 	if (unlikely(!cachep->nodelists[nodeid])) {

mm/slub.c

@@ -1735,7 +1735,7 @@ static __always_inline void *slab_alloc(struct kmem_cache *s,
 	}
 	local_irq_restore(flags);
 
-	if (unlikely((gfpflags & __GFP_ZERO) && object))
+	if (unlikely(gfpflags & __GFP_ZERO) && object)
 		memset(object, 0, objsize);
 
 	kmemcheck_slab_alloc(s, gfpflags, object, c->objsize);
@@ -4371,12 +4371,28 @@ static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si)
 	return len + sprintf(buf + len, "\n");
 }
 
+static void clear_stat(struct kmem_cache *s, enum stat_item si)
+{
+	int cpu;
+
+	for_each_online_cpu(cpu)
+		get_cpu_slab(s, cpu)->stat[si] = 0;
+}
+
 #define STAT_ATTR(si, text) 					\
 static ssize_t text##_show(struct kmem_cache *s, char *buf)	\
 {								\
 	return show_stat(s, buf, si);				\
 }								\
-SLAB_ATTR_RO(text);						\
+static ssize_t text##_store(struct kmem_cache *s,		\
+				const char *buf, size_t length)	\
+{								\
+	if (buf[0] != '0')					\
+		return -EINVAL;					\
+	clear_stat(s, si);					\
+	return length;						\
+}								\
+SLAB_ATTR(text);						\
 
 STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath);
 STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath);