mm: cleanup WORKINGSET_NODES in workingset

WORKINGSET_NODES is not exposed in the memcg stats and thus there is no
need to use the memcg specific stat update functions for it.  In future if
we decide to expose WORKINGSET_NODES in the memcg stats, we can revert
this patch.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Shakeel Butt <[email protected]>
Reviewed-by: Roman Gushchin <[email protected]>
Reviewed-by: T.J. Mercier <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: Yosry Ahmed <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: shakeelb

mm/workingset.c

@@ -618,6 +618,7 @@ struct list_lru shadow_nodes;
 void workingset_update_node(struct xa_node *node)
 {
 	struct address_space *mapping;
+	struct page *page = virt_to_page(node);
 
 	/*
 	 * Track non-empty nodes that contain only shadow entries;
@@ -633,12 +634,12 @@ void workingset_update_node(struct xa_node *node)
 	if (node->count && node->count == node->nr_values) {
 		if (list_empty(&node->private_list)) {
 			list_lru_add_obj(&shadow_nodes, &node->private_list);
-			__inc_lruvec_kmem_state(node, WORKINGSET_NODES);
+			__inc_node_page_state(page, WORKINGSET_NODES);
 		}
 	} else {
 		if (!list_empty(&node->private_list)) {
 			list_lru_del_obj(&shadow_nodes, &node->private_list);
-			__dec_lruvec_kmem_state(node, WORKINGSET_NODES);
+			__dec_node_page_state(page, WORKINGSET_NODES);
 		}
 	}
 }
@@ -742,7 +743,7 @@ static enum lru_status shadow_lru_isolate(struct list_head *item,
 	}
 
 	list_lru_isolate(lru, item);
-	__dec_lruvec_kmem_state(node, WORKINGSET_NODES);
+	__dec_node_page_state(virt_to_page(node), WORKINGSET_NODES);
 
 	spin_unlock(lru_lock);