nvme-pci: move ->cq_vector == -1 check outside of ->q_lock

We only clear it dynamically in nvme_suspend_queue(). When we do, ensure
to do a full flush so that any nvme_queue_rq() invocation will see it.

Ideally we'd kill this check completely, but we're using it to flush
requests on a dying queue.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Jens Axboe 2018-05-17 18:31:49 +02:00 committed by Keith Busch
parent f9dde187fa
commit d1f06f4ae0

View file

@ -872,6 +872,13 @@ static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
struct nvme_command cmnd;
blk_status_t ret;
/*
* We should not need to do this, but we're still using this to
* ensure we can drain requests on a dying queue.
*/
if (unlikely(nvmeq->cq_vector < 0))
return BLK_STS_IOERR;
ret = nvme_setup_cmd(ns, req, &cmnd);
if (ret)
return ret;
@ -889,11 +896,6 @@ static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
blk_mq_start_request(req);
spin_lock_irq(&nvmeq->q_lock);
if (unlikely(nvmeq->cq_vector < 0)) {
ret = BLK_STS_IOERR;
spin_unlock_irq(&nvmeq->q_lock);
goto out_cleanup_iod;
}
__nvme_submit_cmd(nvmeq, &cmnd);
spin_unlock_irq(&nvmeq->q_lock);
return BLK_STS_OK;
@ -1321,6 +1323,12 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq)
nvmeq->cq_vector = -1;
spin_unlock_irq(&nvmeq->q_lock);
/*
* Ensure that nvme_queue_rq() sees it ->cq_vector == -1 without
* having to grab the lock.
*/
mb();
if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q);