X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Fslab.c;h=6f6abef83a1af82432305245755ab690c8363081;hb=ecfe7f093768f7af0959f5be8ec039dcc29724af;hp=a684778b2b41af38e06aa47e5fe66a7a988ad4c7;hpb=2f66b529d9d131971e2509aee5478c61ca258ece;p=linux-2.6

diff --git a/mm/slab.c b/mm/slab.c
index a684778b2b..6f6abef83a 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -883,6 +883,7 @@ static void __slab_error(const char *function, struct kmem_cache *cachep,
   */
 
 static int use_alien_caches __read_mostly = 1;
+static int numa_platform __read_mostly = 1;
 static int __init noaliencache_setup(char *s)
 {
 	use_alien_caches = 0;
@@ -1399,8 +1400,10 @@ void __init kmem_cache_init(void)
 	int order;
 	int node;
 
-	if (num_possible_nodes() == 1)
+	if (num_possible_nodes() == 1) {
 		use_alien_caches = 0;
+		numa_platform = 0;
+	}
 
 	for (i = 0; i < NUM_INIT_LISTS; i++) {
 		kmem_list3_init(&initkmem_list3[i]);
@@ -3558,7 +3561,14 @@ static inline void __cache_free(struct kmem_cache *cachep, void *objp)
 	check_irq_off();
 	objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0));
 
-	if (cache_free_alien(cachep, objp))
+	/*
+	 * Skip calling cache_free_alien() when the platform is not numa.
+	 * This will avoid cache misses that happen while accessing slabp (which
+	 * is per page memory  reference) to get nodeid. Instead use a global
+	 * variable to skip the call, which is mostly likely to be present in
+	 * the cache.
+	 */
+	if (numa_platform && cache_free_alien(cachep, objp))
 		return;
 
 	if (likely(ac->avail < ac->limit)) {