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>
This commit is contained in:
Shaohua Li 2017-05-10 08:47:11 -07:00
parent bb3338d347
commit 23b245c04d
2 changed files with 6 additions and 8 deletions

View File

@ -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);

View File

@ -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,