Commit 09f87186 authored by Jan Kara's avatar Jan Kara Committed by Jens Axboe
Browse files

bfq: Track whether bfq_group is still online 



Track whether bfq_group is still online. We cannot rely on
blkcg_gq->online because that gets cleared only after all policies are
offlined and we need something that gets updated already under
bfqd->lock when we are cleaning up our bfq_group to be able to guarantee
that when we see online bfq_group, it will stay online while we are
holding bfqd->lock lock.

CC: stable@vger.kernel.org
Tested-by: default avatar"yukuai (C)" <yukuai3@huawei.com>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220401102752.8599-7-jack@suse.cz


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 5f550ede

block/bfq-cgroup.c

+2 −1
Original line number Diff line number Diff line
@@ -557,6 +557,7 @@ static void bfq_pd_init(struct blkg_policy_data *pd) 
				   */

	bfqg->bfqd = bfqd;

	bfqg->active_entities = 0;

	bfqg->online = true;

	bfqg->rq_pos_tree = RB_ROOT;

}
@@ -603,7 +604,6 @@ struct bfq_group *bfq_find_set_group(struct bfq_data *bfqd, 
	struct bfq_entity *entity;



	bfqg = bfq_lookup_bfqg(bfqd, blkcg);



	if (unlikely(!bfqg))

		return NULL;
@@ -979,6 +979,7 @@ static void bfq_pd_offline(struct blkg_policy_data *pd) 


put_async_queues:

	bfq_put_async_queues(bfqd, bfqg);

	bfqg->online = false;



	spin_unlock_irqrestore(&bfqd->lock, flags);

	/*

block/bfq-iosched.h

+2 −0
Original line number Diff line number Diff line
@@ -928,6 +928,8 @@ struct bfq_group { 


	/* reference counter (see comments in bfq_bic_update_cgroup) */

	int ref;

	/* Is bfq_group still online? */

	bool online;



	struct bfq_entity entity;

	struct bfq_sched_data sched_data;