[PATCH] dm: Use `clear_and_wake_up_bit()` in device mapper

[Jiangong . Han]

The helper was introduced in 'commit 8236b0ae31c83 ("bdi: wake up
concurrent wb_shutdown() callers.")' as a generic way of doing the same
sequence of operations:
        clear_bit_unlock();
        smp_mb__after_atomic();
        wake_up_bit();

The helper was first implemented to avoid bugs caused by forgetting to
call `wake_up_bit()` after `clear_bit_unlock()`. Replace the open-coded
sequence with the helper to avoid duplicate code and reduce code paths
to maintain.
Suggested-by: c...@agatha.dev
Link: 
https://kernelnewbies.org/Beginner%20Cleanup%20and%20Refactor%20Tasks%20by%20Agatha%20Isabelle%20Moreira#task_001
Link: 
https://kernelnewbies.org/Beginner%20Cleanup%20and%20Refactor%20Tasks%20by%20Agatha%20Isabelle%20Moreira#task_002
Signed-off-by: Jiangong.Han <jiangong....@windriver.com>
---
 drivers/md/dm-snap.c           | 4 +---
 drivers/md/dm-zoned-metadata.c | 8 ++------
 drivers/md/dm-zoned-reclaim.c  | 4 +---
 3 files changed, 4 insertions(+), 12 deletions(-)

diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 1489fda9d24a..c8a9ca1eeae7 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -911,9 +911,7 @@ static int init_hash_tables(struct dm_snapshot *s)
 
 static void merge_shutdown(struct dm_snapshot *s)
 {
-       clear_bit_unlock(RUNNING_MERGE, &s->state_bits);
-       smp_mb__after_atomic();
-       wake_up_bit(&s->state_bits, RUNNING_MERGE);
+       clear_and_wake_up_bit(RUNNING_MERGE, &s->state_bits);
 }
 
 static struct bio *__release_queued_bios_after_merge(struct dm_snapshot *s)
diff --git a/drivers/md/dm-zoned-metadata.c b/drivers/md/dm-zoned-metadata.c
index f4f81c79a080..094b63215882 100644
--- a/drivers/md/dm-zoned-metadata.c
+++ b/drivers/md/dm-zoned-metadata.c
@@ -519,9 +519,7 @@ static void dmz_mblock_bio_end_io(struct bio *bio)
        else
                flag = DMZ_META_READING;
 
-       clear_bit_unlock(flag, &mblk->state);
-       smp_mb__after_atomic();
-       wake_up_bit(&mblk->state, flag);
+       clear_and_wake_up_bit(flag, &mblk->state);
 
        bio_put(bio);
 }
@@ -1910,9 +1908,7 @@ void dmz_unlock_zone_reclaim(struct dm_zone *zone)
        WARN_ON(dmz_is_active(zone));
        WARN_ON(!dmz_in_reclaim(zone));
 
-       clear_bit_unlock(DMZ_RECLAIM, &zone->flags);
-       smp_mb__after_atomic();
-       wake_up_bit(&zone->flags, DMZ_RECLAIM);
+       clear_and_wake_up_bit(DMZ_RECLAIM, &zone->flags);
 }
 
 /*
diff --git a/drivers/md/dm-zoned-reclaim.c b/drivers/md/dm-zoned-reclaim.c
index ad9c7bc21d54..c041413c729e 100644
--- a/drivers/md/dm-zoned-reclaim.c
+++ b/drivers/md/dm-zoned-reclaim.c
@@ -106,9 +106,7 @@ static void dmz_reclaim_kcopy_end(int read_err, unsigned 
long write_err,
        else
                zrc->kc_err = 0;
 
-       clear_bit_unlock(DMZ_RECLAIM_KCOPY, &zrc->flags);
-       smp_mb__after_atomic();
-       wake_up_bit(&zrc->flags, DMZ_RECLAIM_KCOPY);
+       clear_and_wake_up_bit(DMZ_RECLAIM_KCOPY, &zrc->flags);
 }
 
 /*
-- 
2.37.3