From f3b578d9d009a9f670e893cec8579aa069aaaccb Mon Sep 17 00:00:00 2001
From: Mel Gorman <mgorman@suse.de>
Date: Tue, 7 Jan 2014 14:00:42 +0000
Subject: mm: numa: avoid unnecessary work on the failure path

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@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/mm/migrate.c b/mm/migrate.c
index 818c169..e33f0d1 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1726,7 +1726,8 @@ 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;
 	}
 
 	/*
@@ -1800,6 +1801,7 @@ out_dropref:
 	}
 	spin_unlock(&mm->page_table_lock);
 
+out_unlock:
 	unlock_page(page);
 	put_page(page);
 	return 0;
-- 
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