cfq: clear queue pointers from cfqg after unpinning them in cfq_pd_offline

BFQ is already doing a similar thing in its .pd_offline_fn() method
implementation.

While it seems that after commit 4c6994806f
("blk-throttle: fix race between blkcg_bio_issue_check() and cgroup_rmdir()")
was reverted leaving these pointers intact no longer causes crashes
clearing them is still a sensible thing to do to make the code more robust.

Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Maciej S. Szmigiero 2018-10-10 23:16:50 +02:00 committed by Jens Axboe
parent 4822e902f9
commit a2fa8a19b7

View File

@ -1644,14 +1644,20 @@ static void cfq_pd_offline(struct blkg_policy_data *pd)
int i;
for (i = 0; i < IOPRIO_BE_NR; i++) {
if (cfqg->async_cfqq[0][i])
if (cfqg->async_cfqq[0][i]) {
cfq_put_queue(cfqg->async_cfqq[0][i]);
if (cfqg->async_cfqq[1][i])
cfqg->async_cfqq[0][i] = NULL;
}
if (cfqg->async_cfqq[1][i]) {
cfq_put_queue(cfqg->async_cfqq[1][i]);
cfqg->async_cfqq[1][i] = NULL;
}
}
if (cfqg->async_idle_cfqq)
if (cfqg->async_idle_cfqq) {
cfq_put_queue(cfqg->async_idle_cfqq);
cfqg->async_idle_cfqq = NULL;
}
/*
* @blkg is going offline and will be ignored by