From: NeilBrown <neilb@suse.de>
Date: Tue, 31 Jul 2012 00:04:55 +0000 (+1000)
Subject: md: remove duplicated test on ->openers when calling do_md_stop()
X-Git-Tag: v3.6-rc1~21^2~5
X-Git-Url: https://git.kernelconcepts.de/?a=commitdiff_plain;h=90cf195d9bcb4bf70e8b6df5073b05164b279ba0;p=karo-tx-linux.git

md: remove duplicated test on ->openers when calling do_md_stop()

do_md_stop tests mddev->openers while holding ->open_mutex,
and fails if this count is too high.
So callers do not need to check mddev->openers and doing so isn't
very meaningful as they don't hold ->open_mutex so the number could
change.

So remove the unnecessary tests on mddev->openers.
These are not called often enough for there to be any gain in
an early test on ->open_mutex to avoid the need for a slightly more
costly mutex_lock call.

Signed-off-by: NeilBrown <neilb@suse.de>
---

diff --git a/drivers/md/md.c b/drivers/md/md.c
index d5ab4493c8be..f6c46109b071 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -3942,17 +3942,13 @@ array_state_store(struct mddev *mddev, const char *buf, size_t len)
 		break;
 	case clear:
 		/* stopping an active array */
-		if (atomic_read(&mddev->openers) > 0)
-			return -EBUSY;
 		err = do_md_stop(mddev, 0, NULL);
 		break;
 	case inactive:
 		/* stopping an active array */
-		if (mddev->pers) {
-			if (atomic_read(&mddev->openers) > 0)
-				return -EBUSY;
+		if (mddev->pers)
 			err = do_md_stop(mddev, 2, NULL);
-		} else
+		else
 			err = 0; /* already inactive */
 		break;
 	case suspended: