list_lru: don't call list_lru_from_kmem if the list_head is empty

If the list_head is empty then we'll have called list_lru_from_kmem for nothing. Move that call inside of the list_empty if block. Signed-off-by: Jeff Layton <[email protected]> Reviewed-by: Vladimir Davydov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
modi0012 · Sep 8, 2015 · 26f5d76 · 26f5d76
1 parent 21cd3a6
commit 26f5d76
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/mm/list_lru.c b/mm/list_lru.c
@@ -99,8 +99,8 @@ bool list_lru_add(struct list_lru *lru, struct list_head *item)
 	struct list_lru_one *l;
 
 	spin_lock(&nlru->lock);
-	l = list_lru_from_kmem(nlru, item);
 	if (list_empty(item)) {
+		l = list_lru_from_kmem(nlru, item);
 		list_add_tail(item, &l->list);
 		l->nr_items++;
 		spin_unlock(&nlru->lock);
@@ -118,8 +118,8 @@ bool list_lru_del(struct list_lru *lru, struct list_head *item)
 	struct list_lru_one *l;
 
 	spin_lock(&nlru->lock);
-	l = list_lru_from_kmem(nlru, item);
 	if (!list_empty(item)) {
+		l = list_lru_from_kmem(nlru, item);
 		list_del_init(item);
 		l->nr_items--;
 		spin_unlock(&nlru->lock);