Index: linux-2.6.21-rc2/include/linux/slub_def.h
===================================================================
--- linux-2.6.21-rc2.orig/include/linux/slub_def.h	2007-03-01 19:11:08.000000000 -0800
+++ linux-2.6.21-rc2/include/linux/slub_def.h	2007-03-01 19:43:17.000000000 -0800
@@ -27,7 +27,7 @@ struct kmem_cache {
 	int size;		/* Total size of an object */
 	int objects;		/* Number of objects in slab */
 	struct kmem_cache_node local_node;
-	atomic_t refcount;	/* Refcount for destroy */
+	int refcount;		/* Refcount for destroy */
 	void (*ctor)(void *, struct kmem_cache *, unsigned long);
 	void (*dtor)(void *, struct kmem_cache *, unsigned long);
 
Index: linux-2.6.21-rc2/mm/slub.c
===================================================================
--- linux-2.6.21-rc2.orig/mm/slub.c	2007-03-01 19:07:29.000000000 -0800
+++ linux-2.6.21-rc2/mm/slub.c	2007-03-01 19:45:24.000000000 -0800
@@ -82,12 +82,6 @@
 
 static int kmem_size = sizeof(struct kmem_cache);
 
-/*
- * Forward declarations
- */
-static void register_slab(struct kmem_cache *s);
-static void unregister_slab(struct kmem_cache *s);
-
 #ifdef CONFIG_SMP
 static struct notifier_block slab_notifier;
 #endif
@@ -103,7 +97,7 @@ int slab_is_available(void) {
 }
 
 /* A list of all slab caches on the system */
-static DECLARE_RWSEM(slabstat_sem);
+static DECLARE_RWSEM(slub_lock);
 LIST_HEAD(slab_caches);
 
 /********************************************************************
@@ -1251,7 +1245,7 @@ static unsigned long calculate_alignment
 	return ALIGN(align, sizeof(void *));
 }
 
-void free_kmem_cache_nodes(struct kmem_cache *s)
+static void free_kmem_cache_nodes(struct kmem_cache *s)
 {
 #ifdef CONFIG_NUMA
 	int node;
@@ -1273,7 +1267,7 @@ static void init_kmem_cache_node(struct 
 	INIT_LIST_HEAD(&n->partial);
 }
 
-int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
+static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
 {
 #ifdef CONFIG_NUMA
 	int node;
@@ -1330,7 +1324,7 @@ int init_kmem_cache_nodes(struct kmem_ca
 	return 1;
 }
 
-int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags,
+static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags,
 		const char *name, size_t size,
 		size_t align, unsigned long flags,
 		void (*ctor)(void *, struct kmem_cache *, unsigned long),
@@ -1417,7 +1411,7 @@ int kmem_cache_open(struct kmem_cache *s
 	if (!s->objects || s->objects > 65535)
 		goto error;
 
-	atomic_set(&s->refcount, 1);
+	s->refcount = 1;
 
 #ifdef CONFIG_SMP
 	mutex_init(&s->flushing);
@@ -1425,7 +1419,6 @@ int kmem_cache_open(struct kmem_cache *s
 	INIT_DELAYED_WORK(&s->flush, flusher);
 #endif
 	if (init_kmem_cache_nodes(s, gfpflags)) {
-		register_slab(s);
 		return 1;
 	}
 error:
@@ -1508,7 +1501,7 @@ static int free_list(struct kmem_cache *
  * Release all resources used by slab cache
  * (if possible...)
  */
-int kmem_cache_close(struct kmem_cache *s)
+static int kmem_cache_close(struct kmem_cache *s)
 {
 	int node;
 
@@ -1523,7 +1516,6 @@ int kmem_cache_close(struct kmem_cache *
 			return 1;
 	}
 	free_kmem_cache_nodes(s);
-	unregister_slab(s);
 	return 0;
 }
 EXPORT_SYMBOL(kmem_cache_close);
@@ -1534,11 +1526,15 @@ EXPORT_SYMBOL(kmem_cache_close);
  */
 void kmem_cache_destroy(struct kmem_cache *s)
 {
-	if (!atomic_dec_and_test(&s->refcount))
-		return;
-
-	BUG_ON(kmem_cache_close(s));
-	kfree(s);
+	down_write(&slub_lock);
+	if (s->refcount)
+		s->refcount--;
+	else {
+		list_del(&s->list);
+		BUG_ON(kmem_cache_close(s));
+		kfree(s);
+	}
+	up_write(&slub_lock);
 }
 EXPORT_SYMBOL(kmem_cache_destroy);
 
@@ -1652,11 +1648,13 @@ __setup("slub_debug", setup_slub_debug);
 static struct kmem_cache *create_kmalloc_cache(struct kmem_cache *s,
 		const char *name, int size, gfp_t flags)
 {
-
+	down_write(&slub_lock);
 	if (!kmem_cache_open(s, flags, name, size, ARCH_KMALLOC_MINALIGN,
 			0, NULL, NULL))
 		panic("Creation of kmalloc slab %s size=%d failed.\n",
 			name, size);
+	list_add(&s->list, &slab_caches);
+	up_write(&slub_lock);
 	return s;
 }
 
@@ -1819,16 +1817,17 @@ void __init kmem_cache_init(void)
 static struct kmem_cache *kmem_cache_dup(struct kmem_cache *s,
 				gfp_t flags, const char *name)
 {
-	atomic_inc(&s->refcount);
-	down_write(&slabstat_sem);
-	if (!s->aliases)
-		s->aliases = kstrdup(name, flags);
-	else {
-		char *x = s->aliases;
-		s->aliases = kasprintf(flags, "%s/%s", s->aliases, name);
-		kfree(x);
-	}
-	up_write(&slabstat_sem);
+	if (s->refcount == 1) {
+		s->refcount++;
+		if (!s->aliases)
+			s->aliases = kstrdup(name, flags);
+		else {
+			char *x = s->aliases;
+			s->aliases = kasprintf(flags, "%s/%s", s->aliases, name);
+			kfree(x);
+		}
+	} else
+		s = NULL;
 	return s;
 }
 
@@ -1852,7 +1851,6 @@ static struct kmem_cache *find_mergeable
 	align = calculate_alignment(flags, align);
 	size = ALIGN(size, align);
 
-	down_read(&slabstat_sem);
 	list_for_each(h, &slab_caches) {
 		struct kmem_cache *s =
 			container_of(h, struct kmem_cache, list);
@@ -1879,10 +1877,8 @@ static struct kmem_cache *find_mergeable
 		if (s->size - size >= sizeof(void *))
 			continue;
 
-		up_read(&slabstat_sem);
 		return s;
 	}
-	up_read(&slabstat_sem);
 	return NULL;
 }
 
@@ -1893,18 +1889,26 @@ struct kmem_cache *kmem_cache_create(con
 {
 	struct kmem_cache *s;
 
+	down_write(&slub_lock);
 	s = find_mergeable(size, align, flags, dtor, ctor);
 	if (s) {
-		printk(KERN_INFO "SLUB: Merging slab_cache %s size %d"
+		s = kmem_cache_dup(s, GFP_KERNEL, name);
+		if (s) {
+			printk(KERN_INFO "SLUB: Merging slab_cache %s size %d"
 			" with slab_cache %s size %d\n",
 			name, (int)size, s->name, s->size);
-		return kmem_cache_dup(s, GFP_KERNEL, name);
+			goto out;
+		}
+
 	}
 	s = kmalloc(kmem_size, GFP_KERNEL);
 	if (s && kmem_cache_open(s, GFP_KERNEL, kstrdup(name, GFP_KERNEL),
-			size, align, flags, ctor, dtor))
-		return s;
-	kfree(s);
+			size, align, flags, ctor, dtor)) {
+		list_add(&s->list, &slab_caches);
+	} else
+		kfree(s);
+out:
+	up_write(&slub_lock);
 	return NULL;
 }
 EXPORT_SYMBOL(kmem_cache_create);
@@ -1924,20 +1928,6 @@ EXPORT_SYMBOL(kmem_cache_zalloc);
  *			Slab proc interface
  *******************************************************************/
 
-static void register_slab(struct kmem_cache *s)
-{
-	down_write(&slabstat_sem);
-	list_add(&s->list, &slab_caches);
-	up_write(&slabstat_sem);
-}
-
-static void unregister_slab(struct kmem_cache *s)
-{
-	down_write(&slabstat_sem);
-	list_del(&s->list);
-	up_write(&slabstat_sem);
-}
-
 static void print_slubinfo_header(struct seq_file *m)
 {
 	/*
@@ -1958,7 +1948,7 @@ static void *s_start(struct seq_file *m,
 	loff_t n = *pos;
 	struct list_head *p;
 
-	down_read(&slabstat_sem);
+	down_read(&slub_lock);
 	if (!n)
 		print_slubinfo_header(m);
 	p = slab_caches.next;
@@ -1980,7 +1970,7 @@ static void *s_next(struct seq_file *m, 
 
 static void s_stop(struct seq_file *m, void *p)
 {
-	up_read(&slabstat_sem);
+	up_read(&slub_lock);
 }
 
 static void display_nodes(struct seq_file *m, unsigned long *nodes)
@@ -2072,14 +2062,14 @@ static void for_all_slabs(void (*func)(s
 {
 	struct list_head *h;
 
-	down_read(&slabstat_sem);
+	down_read(&slub_lock);
 	list_for_each(h, &slab_caches) {
 		struct kmem_cache *s =
 			container_of(h, struct kmem_cache, list);
 
 		func(s, cpu);
 	}
-	up_read(&slabstat_sem);
+	up_read(&slub_lock);
 }
 
 /*