[PATCH v4 RFC 14/14] dm-raid: remove mddev_suspend/resume()

From: Yu Kuai
Date: Mon Jan 29 2024 - 21:27:23 EST


From: Yu Kuai <yukuai3@xxxxxxxxxx>

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@xxxxxxxxxx>
---
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