[dm-devel] [PATCH 36/41] ext4: do not send discards as barriers

[Tejun Heo]

From: Christoph Hellwig <hch at infradead.org>

ext4 already uses synchronous discards, no need to add I/O barriers.

Signed-off-by: Christoph Hellwig <hch at lst.de>
Signed-off-by: Tejun Heo <tj at kernel.org>
---
 fs/ext4/mballoc.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index df44b34..a22bfef 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2567,7 +2567,7 @@ static inline void ext4_issue_discard(struct super_block *sb,
 	trace_ext4_discard_blocks(sb,
 			(unsigned long long) discard_block, count);
 	ret = sb_issue_discard(sb, discard_block, count, GFP_NOFS,
-			       BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
+			       BLKDEV_IFL_WAIT);
 	if (ret == EOPNOTSUPP) {
 		ext4_warning(sb, "discard not supported, disabling");
 		clear_opt(EXT4_SB(sb)->s_mount_opt, DISCARD);
-- 
1.7.1