mm: workingset: simplify lockdep check in update_node

container_of(node->array, ..., i_pages) just to access i_pages again is an
incredibly roundabout way of accessing node->array itself.  Simplify it.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Pedro Falcato <[email protected]>
Reviewed-by: Matthew Wilcox (Oracle) <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: heatd

mm/workingset.c

@@ -612,7 +612,6 @@ struct list_lru shadow_nodes;
 
 void workingset_update_node(struct xa_node *node)
 {
-	struct address_space *mapping;
 	struct page *page = virt_to_page(node);
 
 	/*
@@ -623,8 +622,7 @@ void workingset_update_node(struct xa_node *node)
 	 * already where they should be. The list_empty() test is safe
 	 * as node->private_list is protected by the i_pages lock.
 	 */
-	mapping = container_of(node->array, struct address_space, i_pages);
-	lockdep_assert_held(&mapping->i_pages.xa_lock);
+	lockdep_assert_held(&node->array->xa_lock);
 
 	if (node->count && node->count == node->nr_values) {
 		if (list_empty(&node->private_list)) {