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From: Yu Kuai <yukuai1@huaweicloud.com>
To: mpatocka@redhat.com,
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	yukuai1@huaweicloud.com,
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Subject: [PATCH v4 RFC 14/14] dm-raid: remove mddev_suspend/resume()
Date: Tue, 30 Jan 2024 10:18:43 +0800
Message-Id: <20240130021843.3608859-15-yukuai1@huaweicloud.com>
In-Reply-To: <20240130021843.3608859-1-yukuai1@huaweicloud.com>
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From: Yu Kuai <yukuai3@huawei.com>

dm_suspend() already make sure that no new IO can be issued and will
wait for all dispatched IO to be done. There is no need to call
mddev_suspend() to make sure that again.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
---
 drivers/md/dm-raid.c |  8 +++-----
 drivers/md/md.c      | 11 +++++++++++
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 5f78cc19d6f3..ed8c28952b14 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -3241,7 +3241,7 @@ static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	rs->md.in_sync = 1;
 
 	/* Has to be held on running the array */
-	mddev_suspend_and_lock_nointr(&rs->md);
+	mddev_lock_nointr(&rs->md);
 
 	/* Keep array frozen until resume. */
 	md_frozen_sync_thread(&rs->md);
@@ -3829,11 +3829,9 @@ static void raid_postsuspend(struct dm_target *ti)
 {
 	struct raid_set *rs = ti->private;
 
-	if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
+	if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags))
 		/* Writes have to be stopped before suspending to avoid deadlocks. */
 		md_stop_writes(&rs->md);
-		mddev_suspend(&rs->md, false);
-	}
 }
 
 static void attempt_restore_of_faulty_devices(struct raid_set *rs)
@@ -4091,7 +4089,7 @@ static void raid_resume(struct dm_target *ti)
 		mddev->ro = 0;
 		mddev->in_sync = 0;
 		md_unfrozen_sync_thread(mddev);
-		mddev_unlock_and_resume(mddev);
+		mddev_unlock(mddev);
 	}
 }
 
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 093abf3ce27b..e3a56a958b47 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -437,6 +437,10 @@ int mddev_suspend(struct mddev *mddev, bool interruptible)
 {
 	int err = 0;
 
+	/* Array is supended from dm_suspend() for dm-raid. */
+	if (!mddev->gendisk)
+		return 0;
+
 	/*
 	 * hold reconfig_mutex to wait for normal io will deadlock, because
 	 * other context can't update super_block, and normal io can rely on
@@ -488,6 +492,13 @@ EXPORT_SYMBOL_GPL(mddev_suspend);
 
 static void __mddev_resume(struct mddev *mddev, bool recovery_needed)
 {
+	/*
+	 * Array is supended from dm_suspend() and resumed from dm_resume() for
+	 * dm-raid.
+	 */
+	if (!mddev->gendisk)
+		return;
+
 	lockdep_assert_not_held(&mddev->reconfig_mutex);
 
 	mutex_lock(&mddev->suspend_mutex);
-- 
2.39.2