SLUB: rename defrag to remote_node_defrag_ratio

The NUMA defrag works by allocating objects from partial slabs on remote
nodes. Rename it to

remote_node_defrag_ratio

to be clear about this.

Signed-off-by: Christoph Lameter <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

include/linux/slub_def.h

···
 #endif
 
 #ifdef CONFIG_NUMA
-	int defrag_ratio;
+	/*
+	 * Defragmentation by allocating from a remote node.
+	 */
+	int remote_node_defrag_ratio;
 	struct kmem_cache_node *node[MAX_NUMNODES];
 #endif
 #ifdef CONFIG_SMP

mm/slub.c

···
 	 * expensive if we do it every time we are trying to find a slab
 	 * with available objects.
 	 */
-	if (!s->defrag_ratio || get_cycles() % 1024 > s->defrag_ratio)
+	if (!s->remote_node_defrag_ratio ||
+			get_cycles() % 1024 > s->remote_node_defrag_ratio)
 		return NULL;
 
 	zonelist = &NODE_DATA(slab_node(current->mempolicy))
···
 
 	s->refcount = 1;
 #ifdef CONFIG_NUMA
-	s->defrag_ratio = 100;
+	s->remote_node_defrag_ratio = 100;
 #endif
 	if (!init_kmem_cache_nodes(s, gfpflags & ~SLUB_DMA))
 		goto error;
···
 SLAB_ATTR_RO(free_calls);
 
 #ifdef CONFIG_NUMA
-static ssize_t defrag_ratio_show(struct kmem_cache *s, char *buf)
+static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf)
 {
-	return sprintf(buf, "%d\n", s->defrag_ratio / 10);
+	return sprintf(buf, "%d\n", s->remote_node_defrag_ratio / 10);
 }
 
-static ssize_t defrag_ratio_store(struct kmem_cache *s,
+static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s,
 				const char *buf, size_t length)
 {
 	int n = simple_strtoul(buf, NULL, 10);
 
 	if (n < 100)
-		s->defrag_ratio = n * 10;
+		s->remote_node_defrag_ratio = n * 10;
 	return length;
 }
-SLAB_ATTR(defrag_ratio);
+SLAB_ATTR(remote_node_defrag_ratio);
 #endif
 
 static struct attribute * slab_attrs[] = {
···
 	&cache_dma_attr.attr,
 #endif
 #ifdef CONFIG_NUMA
-	&defrag_ratio_attr.attr,
+	&remote_node_defrag_ratio_attr.attr,
 #endif
 	NULL
 };