mm: convert anon_vma->lock to a mutex

Straightforward conversion of anon_vma->lock to a mutex.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Tony Luck <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 6 deletions

diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 8847c8c29791..48c32ebf65a7 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -92,12 +92,8 @@ extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd);
 #define wait_split_huge_page(__anon_vma, __pmd)                         \
         do {                                                            \
                 pmd_t *____pmd = (__pmd);                               \
-                spin_unlock_wait(&(__anon_vma)->root->lock);            \
-                /*                                                      \
-                 * spin_unlock_wait() is just a loop in C and so the    \
-                 * CPU can reorder anything around it.                  \
-                 */                                                     \
-                smp_mb();                                               \
+                anon_vma_lock(__anon_vma);                              \
+                anon_vma_unlock(__anon_vma);                            \
                 BUG_ON(pmd_trans_splitting(*____pmd) ||                 \
                        pmd_trans_huge(*____pmd));                       \
         } while (0)