1 files changed, 23 insertions, 11 deletions

diff --git a/mm/list_lru.c b/mm/list_lru.c
index e1da19fac1b3..28237476b055 100644
--- a/mm/list_lru.c
+++ b/mm/list_lru.c
@@ -42,6 +42,10 @@ static void list_lru_unregister(struct list_lru *lru)
 #ifdef CONFIG_MEMCG_KMEM
 static inline bool list_lru_memcg_aware(struct list_lru *lru)
 {
+	/*
+	 * This needs node 0 to be always present, even
+	 * in the systems supporting sparse numa ids.
+	 */
 	return !!lru->node[0].memcg_lrus;
 }
 
@@ -377,16 +381,20 @@ static int memcg_init_list_lru(struct list_lru *lru, bool memcg_aware)
 {
 	int i;
 
-	for (i = 0; i < nr_node_ids; i++) {
-		if (!memcg_aware)
-			lru->node[i].memcg_lrus = NULL;
-		else if (memcg_init_list_lru_node(&lru->node[i]))
+	if (!memcg_aware)
+		return 0;
+
+	for_each_node(i) {
+		if (memcg_init_list_lru_node(&lru->node[i]))
 			goto fail;
 	}
 	return 0;
 fail:
-	for (i = i - 1; i >= 0; i--)
+	for (i = i - 1; i >= 0; i--) {
+		if (!lru->node[i].memcg_lrus)
+			continue;
 		memcg_destroy_list_lru_node(&lru->node[i]);
+	}
 	return -ENOMEM;
 }
 
@@ -397,7 +405,7 @@ static void memcg_destroy_list_lru(struct list_lru *lru)
 	if (!list_lru_memcg_aware(lru))
 		return;
 
-	for (i = 0; i < nr_node_ids; i++)
+	for_each_node(i)
 		memcg_destroy_list_lru_node(&lru->node[i]);
 }
 
@@ -409,16 +417,20 @@ static int memcg_update_list_lru(struct list_lru *lru,
 	if (!list_lru_memcg_aware(lru))
 		return 0;
 
-	for (i = 0; i < nr_node_ids; i++) {
+	for_each_node(i) {
 		if (memcg_update_list_lru_node(&lru->node[i],
 					       old_size, new_size))
 			goto fail;
 	}
 	return 0;
 fail:
-	for (i = i - 1; i >= 0; i--)
+	for (i = i - 1; i >= 0; i--) {
+		if (!lru->node[i].memcg_lrus)
+			continue;
+
 		memcg_cancel_update_list_lru_node(&lru->node[i],
 						  old_size, new_size);
+	}
 	return -ENOMEM;
 }
 
@@ -430,7 +442,7 @@ static void memcg_cancel_update_list_lru(struct list_lru *lru,
 	if (!list_lru_memcg_aware(lru))
 		return;
 
-	for (i = 0; i < nr_node_ids; i++)
+	for_each_node(i)
 		memcg_cancel_update_list_lru_node(&lru->node[i],
 						  old_size, new_size);
 }
@@ -485,7 +497,7 @@ static void memcg_drain_list_lru(struct list_lru *lru,
 	if (!list_lru_memcg_aware(lru))
 		return;
 
-	for (i = 0; i < nr_node_ids; i++)
+	for_each_node(i)
 		memcg_drain_list_lru_node(&lru->node[i], src_idx, dst_idx);
 }
 
@@ -522,7 +534,7 @@ int __list_lru_init(struct list_lru *lru, bool memcg_aware,
 	if (!lru->node)
 		goto out;
 
-	for (i = 0; i < nr_node_ids; i++) {
+	for_each_node(i) {
 		spin_lock_init(&lru->node[i].lock);
 		if (key)
 			lockdep_set_class(&lru->node[i].lock, key);