Index: linux-2.6.21-rc5-mm2/mm/slub.c
===================================================================
--- linux-2.6.21-rc5-mm2.orig/mm/slub.c	2007-03-30 10:11:21.000000000 -0700
+++ linux-2.6.21-rc5-mm2/mm/slub.c	2007-03-30 10:11:30.000000000 -0700
@@ -347,6 +347,9 @@ static void init_object(struct kmem_cach
 {
 	u8 *p = object;
 
+	if (s->objects == 1)
+		return;
+
 	if (s->flags & __OBJECT_POISON) {
 		memset(p, POISON_FREE, s->objsize - 1);
 		p[s->objsize -1] = POISON_END;
@@ -468,6 +471,10 @@ static int check_object(struct kmem_cach
 	u8 *p = object;
 	u8 *endobject = object + s->objsize;
 
+	/* Single object slabs do not get policed */
+	if (s->objects == 1)
+		return 1;
+
 	if (s->flags & SLAB_RED_ZONE) {
 		if (!check_bytes(endobject,
 			active ? SLUB_RED_ACTIVE : SLUB_RED_INACTIVE,
@@ -556,6 +563,9 @@ static int on_freelist(struct kmem_cache
 	void *fp = page->freelist;
 	void *object = NULL;
 
+	if (s->objects == 1)
+		return 0;
+
 	while (fp && nr <= s->objects) {
 		if (fp == search)
 			return 1;
@@ -754,7 +764,8 @@ static struct page *new_slab(struct kmem
 	page->slab = s;
 	page->flags |= 1 << PG_slab;
 	if (s->flags & (SLAB_DEBUG_FREE | SLAB_RED_ZONE | SLAB_POISON |
-			SLAB_STORE_USER | SLAB_TRACE))
+			SLAB_STORE_USER | SLAB_TRACE) ||
+			s->objects == 1)
 		page->flags |= 1 << PG_error;
 
 	if (s->objects > 1) {
@@ -1168,6 +1179,11 @@ new_slab:
 			return NULL;
 		}
 
+		if (s->objects == 1) {
+			local_irq_restore(flags);
+			return page_address(page);
+		}
+
 		if (s->cpu_slab[cpu]) {
 			/*
 			 * Someone else populated the cpu_slab while
@@ -1229,6 +1245,10 @@ static void slab_free(struct kmem_cache 
 	unsigned long flags;
 
 	local_irq_save(flags);
+
+	if (unlikely(PageError(page)) && s->objects == 1)
+		goto single_object_slab;
+
 	slab_lock(page);
 
 	if (unlikely(PageError(page)) &&
@@ -1239,40 +1259,31 @@ static void slab_free(struct kmem_cache 
 	page->freelist = object;
 	page->inuse--;
 
-	if (unlikely(PageActive(page)))
-		/*
-		 * Cpu slabs are never on partial lists and are
-		 * never freed.
-		 */
+	if (likely(PageActive(page) || (page->inuse && prior)))
 		goto out_unlock;
 
-	if (likely(page->inuse)) {
+	if (!prior) {
 		/*
-		 * Objects left in the slab. If it
-		 * was not on the partial list before
-		 * then add it.
+		 * The slab was full before. It will have one free
+		 * object now. So move to the partial list.
 		 */
-		if (unlikely(!prior))
-			add_partial(s, page);
-out_unlock:
-		slab_unlock(page);
-		local_irq_restore(flags);
-		return;
+		add_partial(s, page);
+		goto out_unlock;
 	}
 
 	/*
 	 * All object have been freed.
 	 */
-	if (prior)
-		/*
-		 * The slab was partially used before and is empty
-		 * now. So remove from partial list.
-		 */
-		remove_partial(s, page);
-
+	remove_partial(s, page);
 	slab_unlock(page);
+single_object_slab:
 	discard_slab(s, page);
 	local_irq_restore(flags);
+	return;
+
+out_unlock:
+	slab_unlock(page);
+	local_irq_restore(flags);
 }
 
 void kmem_cache_free(struct kmem_cache *s, void *x)