From 7d8224574cbd2326a6be00f319f5f7597abec3f6 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Mon, 24 Jun 2013 12:03:57 -0400 Subject: [PATCH] NVMe: Call nvme_process_cq from submission path Since we have the queue locked, it makes sense to check if there are any completion queue entries on the queue before we release the lock. If there are, it may save an interrupt and reduce latency for the I/Os that happened to complete. This happens fairly often for some workloads. Signed-off-by: Matthew Wilcox --- drivers/block/nvme-core.c | 39 ++++++++++++++++++++------------------- 1 file changed, 20 insertions(+), 19 deletions(-) diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c index eb4a91f3bf41..07d527c66eb4 100644 --- a/drivers/block/nvme-core.c +++ b/drivers/block/nvme-core.c @@ -738,25 +738,6 @@ static int nvme_submit_bio_queue(struct nvme_queue *nvmeq, struct nvme_ns *ns, return result; } -static void nvme_make_request(struct request_queue *q, struct bio *bio) -{ - struct nvme_ns *ns = q->queuedata; - struct nvme_queue *nvmeq = get_nvmeq(ns->dev); - int result = -EBUSY; - - spin_lock_irq(&nvmeq->q_lock); - if (bio_list_empty(&nvmeq->sq_cong)) - result = nvme_submit_bio_queue(nvmeq, ns, bio); - if (unlikely(result)) { - if (bio_list_empty(&nvmeq->sq_cong)) - add_wait_queue(&nvmeq->sq_full, &nvmeq->sq_cong_wait); - bio_list_add(&nvmeq->sq_cong, bio); - } - - spin_unlock_irq(&nvmeq->q_lock); - put_nvmeq(nvmeq); -} - static int nvme_process_cq(struct nvme_queue *nvmeq) { u16 head, phase; @@ -797,6 +778,26 @@ static int nvme_process_cq(struct nvme_queue *nvmeq) return 1; } +static void nvme_make_request(struct request_queue *q, struct bio *bio) +{ + struct nvme_ns *ns = q->queuedata; + struct nvme_queue *nvmeq = get_nvmeq(ns->dev); + int result = -EBUSY; + + spin_lock_irq(&nvmeq->q_lock); + if (bio_list_empty(&nvmeq->sq_cong)) + result = nvme_submit_bio_queue(nvmeq, ns, bio); + if (unlikely(result)) { + if (bio_list_empty(&nvmeq->sq_cong)) + add_wait_queue(&nvmeq->sq_full, &nvmeq->sq_cong_wait); + bio_list_add(&nvmeq->sq_cong, bio); + } + + nvme_process_cq(nvmeq); + spin_unlock_irq(&nvmeq->q_lock); + put_nvmeq(nvmeq); +} + static irqreturn_t nvme_irq(int irq, void *data) { irqreturn_t result; -- 2.39.5