From: Heinz Mauelshagen <heinzm@redhat.com>
Date: Wed, 15 Jun 2016 16:39:17 +0000 (+0200)
Subject: dm raid: avoid superfluous memory barriers on static metadata
X-Git-Tag: v4.8-rc1~160^2~38
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ff4a88bf1cedbe73ece1a6fad34650f21c06167c;p=thirdparty%2Fkernel%2Flinux.git

dm raid: avoid superfluous memory barriers on static metadata

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 248053d845283..4bf7747a25a9a 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -366,14 +366,12 @@ static bool rs_is_reshapable(struct raid_set *rs)
 /* Return true, if raid set in @rs is recovering */
 static bool rs_is_recovering(struct raid_set *rs)
 {
-	smp_rmb();
 	return rs->md.recovery_cp != MaxSector;
 }
 
 /* Return true, if raid set in @rs is reshaping */
 static bool rs_is_reshaping(struct raid_set *rs)
 {
-	smp_rmb();
 	return rs->md.reshape_position != MaxSector;
 }
 
@@ -1484,7 +1482,6 @@ static int rs_check_takeover(struct raid_set *rs)
 	struct mddev *mddev = &rs->md;
 	unsigned int near_copies;
 
-	smp_rmb();
 	if (rs->md.degraded) {
 		rs->ti->error = "Can't takeover degraded raid set";
 		return -EPERM;
@@ -1758,8 +1755,6 @@ static int rs_check_reshape(struct raid_set *rs)
 {
 	struct mddev *mddev = &rs->md;
 
-	smp_rmb(); /* Make sure we access recent reshape position */
-
 	if (!mddev->pers || !mddev->pers->check_reshape)
 		rs->ti->error = "Reshape not supported";
 	else if (mddev->degraded)