blk-mq: release driver tag on a requeue event

We don't want to hold on to this resource when we have a scheduler
attached.

Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Tested-by: Hannes Reinecke <hare@suse.com>
This commit is contained in:
Jens Axboe 2017-01-26 12:32:32 -07:00
parent 3c782d67c1
commit 99cf1dc580

View File

@ -879,6 +879,21 @@ static bool blk_mq_get_driver_tag(struct request *rq,
return false;
}
static void blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
struct request *rq)
{
if (rq->tag == -1 || rq->internal_tag == -1)
return;
blk_mq_put_tag(hctx, hctx->tags, rq->mq_ctx, rq->tag);
rq->tag = -1;
if (rq->rq_flags & RQF_MQ_INFLIGHT) {
rq->rq_flags &= ~RQF_MQ_INFLIGHT;
atomic_dec(&hctx->nr_active);
}
}
/*
* If we fail getting a driver tag because all the driver tags are already
* assigned and on the dispatch list, BUT the first entry does not have a
@ -951,6 +966,7 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list)
queued++;
break;
case BLK_MQ_RQ_QUEUE_BUSY:
blk_mq_put_driver_tag(hctx, rq);
list_add(&rq->queuelist, list);
__blk_mq_requeue_request(rq);
break;