mm/memcg: revise the using condition of lock_page_lruvec function series

lock_page_lruvec() and its variants are safe to use under the same conditions as commit_charge(): add lock_page_memcg() to the comment. Polished with Hugh Dickins' suggestions, thanks! Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Alex Shi <[email protected]> Acked-by: Hugh Dickins <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Vladimir Davydov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
vieko · Feb 24, 2021 · d7e3aba · d7e3aba
1 parent fff66b7
commit d7e3aba
Showing 1 changed file with 5 additions and 4 deletions.
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
@@ -1346,10 +1346,11 @@ void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page)
  * lock_page_lruvec - lock and return lruvec for a given page.
  * @page: the page
  *
- * This series functions should be used in either conditions:
- * PageLRU is cleared or unset
- * or page->_refcount is zero
- * or page is locked.
+ * These functions are safe to use under any of the following conditions:
+ * - page locked
+ * - PageLRU cleared
+ * - lock_page_memcg()
+ * - page->_refcount is zero
  */
 struct lruvec *lock_page_lruvec(struct page *page)
 {