---
 mm/slub.c |   41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

Index: linux-2.6/mm/slub.c
===================================================================
--- linux-2.6.orig/mm/slub.c	2007-10-18 13:31:20.000000000 -0700
+++ linux-2.6/mm/slub.c	2007-10-18 13:31:28.000000000 -0700
@@ -196,6 +196,8 @@ static inline void ClearSlabDebug(struct
 /* Enable to test recovery from slab corruption on boot */
 #undef SLUB_RESILIENCY_TEST
 
+#define SLUB_ATOMIC
+
 #if PAGE_SHIFT <= 12
 
 /*
@@ -1261,6 +1263,7 @@ static void discard_slab(struct kmem_cac
 	free_slab(s, page);
 }
 
+#ifndef SLUB_ATOMIC
 /*
  * Per slab locking using the pagelock
  */
@@ -1281,6 +1284,7 @@ static __always_inline int slab_trylock(
 	rc = bit_spin_trylock(PG_locked, &page->flags);
 	return rc;
 }
+#endif
 
 /*
  * Management of partially allocated slabs
@@ -1440,11 +1444,20 @@ static inline void **free_object(struct 
 {
 	void **prior;
 
+#ifdef SLUB_ATOMIC
+	do {
+		prior = page->freelist;
+		object[offset] = prior;
+	} while (cmpxchg(&page->freelist, prior, object) != prior);
+
+#else
 	slab_lock(page);
 	prior = page->freelist;
 	object[offset] = prior;
 	page->freelist = object;
 	slab_unlock(page);
+#endif
+
 	return prior;
 }
 
@@ -1455,11 +1468,19 @@ static inline void **alloc_object(struct
 {
 	void **object;
 
+#ifdef SLUB_ATOMIC
+	do {
+		object = page->freelist;
+		if (!object)
+			return NULL;
+	} while (cmpxchg(&page->freelist, object, object[offset]) != object);
+#else
 	slab_lock(page);
 	object = page->freelist;
 	if (object)
 		page->freelist = object[offset];
 	slab_unlock(page);
+#endif
 	return object;
 }
 
@@ -1470,10 +1491,14 @@ static inline void **get_freelist(struct
 {
 	void **list;
 
+#ifdef SLUB_ATOMIC
+	list = xchg(&page->freelist, NULL);
+#else
 	slab_lock(page);
 	list = page->freelist;
 	page->freelist = NULL;
 	slab_unlock(page);
+#endif
 	return list;
 }
 
@@ -1482,9 +1507,17 @@ static inline void **free_cpu_object(str
 {
 	void **prior;
 
+#ifdef SLUB_ATOMIC
+	do {
+		prior = c->freelist;
+		object[c->offset] = prior;
+	} while (cmpxchg_local(&c->freelist, prior, object) != prior);
+
+#else
 	prior = c->freelist;
 	object[c->offset] = prior;
 	c->freelist = object;
+#endif
 	return prior;
 }
 
@@ -1495,9 +1528,17 @@ static inline void **alloc_cpu_object(st
 {
 	void **object;
 
+#ifdef SLUB_ATOMIC
+	do {
+		object = c->freelist;
+		if (!object)
+			return NULL;
+	} while (cmpxchg_local(&c->freelist, object, object[c->offset]) != object);
+#else
 	object = c->freelist;
 	if (object)
 		c->freelist = object[c->offset];
+#endif
 	return object;
 }