[PATCH] mm: remove unused marco writeback

[Alex Shi]

Unlike others we don't use the marco writeback. so let's remove it to
tame gcc warning:

mm/memory-failure.c:827: warning: macro "writeback" is not used
[-Wunused-macros]

Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
Cc: Naoya Horiguchi <naoya.horiguchi@xxxxxxx> 
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> 
Cc: linux-mm@xxxxxxxxx 
Cc: linux-kernel@xxxxxxxxxxxxxxx 
---
 mm/memory-failure.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index f1aa6433f404..3a97440cdf8c 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -824,7 +824,6 @@ static int me_huge_page(struct page *p, unsigned long pfn)
 #define sc		((1UL << PG_swapcache) | (1UL << PG_swapbacked))
 #define unevict		(1UL << PG_unevictable)
 #define mlock		(1UL << PG_mlocked)
-#define writeback	(1UL << PG_writeback)
 #define lru		(1UL << PG_lru)
 #define head		(1UL << PG_head)
 #define slab		(1UL << PG_slab)
@@ -873,7 +872,6 @@ static int me_huge_page(struct page *p, unsigned long pfn)
 #undef sc
 #undef unevict
 #undef mlock
-#undef writeback
 #undef lru
 #undef head
 #undef slab
-- 
1.8.3.1