Merge tag 'v3.15-rc1' into perf/urgent

Pick up the latest fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 12 insertions, 2 deletions

diff --git a/mm/rmap.c b/mm/rmap.c
index 11cf322f813..9c3e77396d1 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1332,9 +1332,19 @@ static int try_to_unmap_cluster(unsigned long cursor, unsigned int *mapcount,
 		BUG_ON(!page || PageAnon(page));
 
 		if (locked_vma) {
-			mlock_vma_page(page);   /* no-op if already mlocked */
-			if (page == check_page)
+			if (page == check_page) {
+				/* we know we have check_page locked */
+				mlock_vma_page(page);
 				ret = SWAP_MLOCK;
+			} else if (trylock_page(page)) {
+				/*
+				 * If we can lock the page, perform mlock.
+				 * Otherwise leave the page alone, it will be
+				 * eventually encountered again later.
+				 */
+				mlock_vma_page(page);
+				unlock_page(page);
+			}
 			continue;	/* don't unmap */
 		}