[PATCH 3.11 149/208] mm: numa: avoid unnecessary work on the failure path

[Luis Henriques]

3.11.10.3 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Mel Gorman <mgorman at suse.de>

commit eb4489f69f224356193364dc2762aa009738ca7f upstream.

If a PMD changes during a THP migration then migration aborts but the
failure path is doing more work than is necessary.

Signed-off-by: Mel Gorman <mgorman at suse.de>
Reviewed-by: Rik van Riel <riel at redhat.com>
Cc: Alex Thorlton <athorlton at sgi.com>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 mm/migrate.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mm/migrate.c b/mm/migrate.c
index 65bbca5..cde4b34 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1723,7 +1723,8 @@ fail_putback:
 		putback_lru_page(page);
 		mod_zone_page_state(page_zone(page),
 			 NR_ISOLATED_ANON + page_lru, -HPAGE_PMD_NR);
-		goto out_fail;
+
+		goto out_unlock;
 	}
 
 	/*
@@ -1797,6 +1798,7 @@ out_dropref:
 	}
 	spin_unlock(&mm->page_table_lock);
 
+out_unlock:
 	unlock_page(page);
 	put_page(page);
 	return 0;
-- 
1.8.3.2