md/raid1/10: avoid unnecessary locking
If we add bios to block plugging list, locking is unnecessry, since the block
unplug is guaranteed not to run at that time.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 7c1f733..a17ed62 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1529,17 +1529,16 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
plug = container_of(cb, struct raid1_plug_cb, cb);
else
plug = NULL;
- spin_lock_irqsave(&conf->device_lock, flags);
if (plug) {
bio_list_add(&plug->pending, mbio);
plug->pending_cnt++;
} else {
+ spin_lock_irqsave(&conf->device_lock, flags);
bio_list_add(&conf->pending_bio_list, mbio);
conf->pending_count++;
- }
- spin_unlock_irqrestore(&conf->device_lock, flags);
- if (!plug)
+ spin_unlock_irqrestore(&conf->device_lock, flags);
md_wakeup_thread(mddev->thread);
+ }
}
r1_bio_write_done(r1_bio);
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 6b86a00..4343d7f 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1282,17 +1282,16 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio,
plug = container_of(cb, struct raid10_plug_cb, cb);
else
plug = NULL;
- spin_lock_irqsave(&conf->device_lock, flags);
if (plug) {
bio_list_add(&plug->pending, mbio);
plug->pending_cnt++;
} else {
+ spin_lock_irqsave(&conf->device_lock, flags);
bio_list_add(&conf->pending_bio_list, mbio);
conf->pending_count++;
- }
- spin_unlock_irqrestore(&conf->device_lock, flags);
- if (!plug)
+ spin_unlock_irqrestore(&conf->device_lock, flags);
md_wakeup_thread(mddev->thread);
+ }
}
static void raid10_write_request(struct mddev *mddev, struct bio *bio,