---
 mm/slub.c |   63 ++++++++++++++++++++++++++------------------------------------
 1 file changed, 27 insertions(+), 36 deletions(-)

Index: linux-2.6/mm/slub.c
===================================================================
--- linux-2.6.orig/mm/slub.c	2007-10-18 14:07:56.000000000 -0700
+++ linux-2.6/mm/slub.c	2007-10-18 14:09:34.000000000 -0700
@@ -1314,17 +1314,13 @@ static void add_partial(struct kmem_cach
  *
  * Must hold list_lock.
  */
-static inline int lock_and_freeze_slab(struct kmem_cache_node *n, struct page *page)
+static inline void lock_and_freeze_slab(struct kmem_cache_node *n, struct page *page)
 {
 	BUG_ON(!SlabPartial(page));
-	if (slab_trylock(page)) {
-		list_del(&page->lru);
-		n->nr_partial--;
-		SetSlabFrozen(page);
-		ClearSlabPartial(page);
-		return 1;
-	}
-	return 0;
+	list_del(&page->lru);
+	n->nr_partial--;
+	SetSlabFrozen(page);
+	ClearSlabPartial(page);
 }
 
 /*
@@ -1344,11 +1340,11 @@ static struct page *get_partial_node(str
 		return NULL;
 
 	spin_lock(&n->list_lock);
-	list_for_each_entry(page, &n->partial, lru)
-		if (lock_and_freeze_slab(n, page))
-			goto out;
-	page = NULL;
-out:
+	if (n->nr_partial)
+		lock_and_freeze_slab(n, container_of(n->partial.next,
+							struct page, lru));
+	else
+		page = NULL;
 	spin_unlock(&n->list_lock);
 	return page;
 }
@@ -1437,7 +1433,6 @@ static void unfreeze_slab(struct kmem_ca
 		add_partial(s, page, tail);
 	else
 		add_full(s, page);
-	slab_unlock(page);
 }
 
 /* Free an object in a slab and return the old freelist pointer */
@@ -1445,9 +1440,11 @@ static inline void **free_object(struct 
 {
 	void **prior;
 
+	slab_lock(page);
 	prior = page->freelist;
 	object[offset] = prior;
 	page->freelist = object;
+	slab_unlock(page);
 	return prior;
 }
 
@@ -1458,9 +1455,11 @@ static inline void **alloc_object(struct
 {
 	void **object;
 
+	slab_lock(page);
 	object = page->freelist;
 	if (object)
 		page->freelist = object[offset];
+	slab_unlock(page);
 	return object;
 }
 
@@ -1471,8 +1470,10 @@ static inline void **get_freelist(struct
 {
 	void **list;
 
+	slab_lock(page);
 	list = page->freelist;
 	page->freelist = NULL;
+	slab_unlock(page);
 	return list;
 }
 
@@ -1505,7 +1506,6 @@ static void deactivate_slab(struct kmem_
 
 static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
 {
-	slab_lock(c->page);
 	deactivate_slab(s, c);
 }
 
@@ -1580,7 +1580,6 @@ static void *__slab_alloc(struct kmem_ca
 	if (!c->page)
 		goto new_slab;
 
-	slab_lock(c->page);
 	if (unlikely(!node_match(c, node)))
 		goto another_slab;
 load_freelist:
@@ -1593,7 +1592,6 @@ load_freelist:
 
 	c->freelist = object[c->offset];
 	c->node = page_to_nid(c->page);
-	slab_unlock(c->page);
 	return object;
 
 another_slab:
@@ -1630,19 +1628,20 @@ new_slab:
 				 * want the current one since its cache hot
 				 */
 				discard_slab(s, new);
-				slab_lock(c->page);
 				goto load_freelist;
 			}
 			/* New slab does not fit our expectations */
 			flush_slab(s, c);
 		}
-		slab_lock(new);
 		SetSlabFrozen(new);
 		c->page = new;
 		goto load_freelist;
 	}
 	return NULL;
 debug:
+	/* FIXME: Thjs onlu works on UP. There needs to be some way
+	 * to guarantee slab consistency.
+	 */
 	if (!c->page->freelist)
 		goto another_slab;
 	if (!alloc_debug_processing(s, c->page, c->page->freelist, addr))
@@ -1650,7 +1649,6 @@ debug:
 
 	object = alloc_object(c->page, c->offset);
 	c->node = -1;
-	slab_unlock(c->page);
 	return object;
 }
 
@@ -1717,8 +1715,6 @@ static void __slab_free(struct kmem_cach
 	void *prior;
 	void **object = (void *)x;
 
-	slab_lock(page);
-
 	if (unlikely(SlabDebug(page)))
 		goto debug;
 checks_ok:
@@ -1730,15 +1726,12 @@ checks_ok:
 	 */
 	if (unlikely(!prior))
 		add_partial(s, page, 0);
-
-out_unlock:
-	slab_unlock(page);
 	return;
 
 debug:
-	if (!free_debug_processing(s, page, x, addr))
-		goto out_unlock;
-	goto checks_ok;
+	if (free_debug_processing(s, page, x, addr))
+		goto checks_ok;
+	return;
 }
 
 /*
@@ -2761,7 +2754,7 @@ int kmem_cache_shrink(struct kmem_cache 
 		list_for_each_entry_safe(page, t, &n->partial, lru) {
 			int inuse = count_inuse(s, page);
 
-			if (!inuse && slab_trylock(page)) {
+			if (!inuse) {
 				/*
 				 * Must hold slab lock here because slab_free
 				 * may have freed the last object and be
@@ -2770,7 +2763,6 @@ int kmem_cache_shrink(struct kmem_cache 
 				ClearSlabPartial(page);
 				list_del(&page->lru);
 				n->nr_partial--;
-				slab_unlock(page);
 				discard_slab(s, page);
 			} else {
 				list_move(&page->lru,
@@ -3103,12 +3095,11 @@ static int validate_slab(struct kmem_cac
 static void validate_slab_slab(struct kmem_cache *s, struct page *page,
 						unsigned long *map)
 {
-	if (slab_trylock(page)) {
-		validate_slab(s, page, map);
-		slab_unlock(page);
-	} else
-		printk(KERN_INFO "SLUB %s: Skipped busy slab 0x%p\n",
-			s->name, page);
+	/*
+	 * FIXME: Need some way to  stop allocs and free from the slab
+	 * to be inspected.
+	 */
+	validate_slab(s, page, map);
 
 	if (s->flags & DEBUG_DEFAULT_FLAGS) {
 		if (!SlabDebug(page))