Commit 397c699f authored Jun 06, 2018 by Keith Busch Committed by Jens Axboe Jun 08, 2018

nvme-pci: remove unnecessary completion doorbell check



The nvme pci driver never unmaps the doorbell registers while the requests
are active, so we can always safely update the completion queue head.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent 0bc88192

drivers/nvme/host/pci.c

+3 −5

Original line number	Diff line number	Diff line
		@@ -920,12 +920,10 @@ static inline void nvme_ring_cq_doorbell(struct nvme_queue *nvmeq)
		{
		u16 head = nvmeq->cq_head;

		if (likely(nvmeq->cq_vector >= 0)) {
		if (nvme_dbbuf_update_and_check_event(head, nvmeq->dbbuf_cq_db,
		nvmeq->dbbuf_cq_ei))
		writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
		}
		}

		static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx)
		{