From 287f329e3131a4e7d7ce9a7e8e6189698d1763f8 Mon Sep 17 00:00:00 2001 From: Yamin Friedman Date: Mon, 13 Jul 2020 11:53:29 +0300 Subject: [PATCH] nvme-rdma: use new shared CQ mechanism Has the driver use shared CQs providing ~10%-20% improvement as seen in the patch introducing shared CQs. Instead of opening a CQ for each QP per controller connected, a CQ for each QP will be provided by the RDMA core driver that will be shared between the QPs on that core reducing interrupt overhead. Signed-off-by: Yamin Friedman Signed-off-by: Max Gurtovoy Reviewed-by: Or Gerlitz Reviewed-by: Sagi Grimberg Signed-off-by: Christoph Hellwig --- drivers/nvme/host/rdma.c | 77 ++++++++++++++++++++++++++++++++---------------- 1 file changed, 51 insertions(+), 26 deletions(-) diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c index e881f87..467da08 100644 --- a/drivers/nvme/host/rdma.c +++ b/drivers/nvme/host/rdma.c @@ -96,6 +96,7 @@ struct nvme_rdma_queue { int cm_error; struct completion cm_done; bool pi_support; + int cq_size; }; struct nvme_rdma_ctrl { @@ -275,6 +276,7 @@ static int nvme_rdma_create_qp(struct nvme_rdma_queue *queue, const int factor) init_attr.recv_cq = queue->ib_cq; if (queue->pi_support) init_attr.create_flags |= IB_QP_CREATE_INTEGRITY_EN; + init_attr.qp_context = queue; ret = rdma_create_qp(queue->cm_id, dev->pd, &init_attr); @@ -409,6 +411,14 @@ out_err: return NULL; } +static void nvme_rdma_free_cq(struct nvme_rdma_queue *queue) +{ + if (nvme_rdma_poll_queue(queue)) + ib_free_cq(queue->ib_cq); + else + ib_cq_pool_put(queue->ib_cq, queue->cq_size); +} + static void nvme_rdma_destroy_queue_ib(struct nvme_rdma_queue *queue) { struct nvme_rdma_device *dev; @@ -430,7 +440,7 @@ static void nvme_rdma_destroy_queue_ib(struct nvme_rdma_queue *queue) * the destruction of the QP shouldn't use rdma_cm API. */ ib_destroy_qp(queue->qp); - ib_free_cq(queue->ib_cq); + nvme_rdma_free_cq(queue); nvme_rdma_free_ring(ibdev, queue->rsp_ring, queue->queue_size, sizeof(struct nvme_completion), DMA_FROM_DEVICE); @@ -450,13 +460,42 @@ static int nvme_rdma_get_max_fr_pages(struct ib_device *ibdev, bool pi_support) return min_t(u32, NVME_RDMA_MAX_SEGMENTS, max_page_list_len - 1); } +static int nvme_rdma_create_cq(struct ib_device *ibdev, + struct nvme_rdma_queue *queue) +{ + int ret, comp_vector, idx = nvme_rdma_queue_idx(queue); + enum ib_poll_context poll_ctx; + + /* + * Spread I/O queues completion vectors according their queue index. + * Admin queues can always go on completion vector 0. + */ + comp_vector = (idx == 0 ? idx : idx - 1) % ibdev->num_comp_vectors; + + /* Polling queues need direct cq polling context */ + if (nvme_rdma_poll_queue(queue)) { + poll_ctx = IB_POLL_DIRECT; + queue->ib_cq = ib_alloc_cq(ibdev, queue, queue->cq_size, + comp_vector, poll_ctx); + } else { + poll_ctx = IB_POLL_SOFTIRQ; + queue->ib_cq = ib_cq_pool_get(ibdev, queue->cq_size, + comp_vector, poll_ctx); + } + + if (IS_ERR(queue->ib_cq)) { + ret = PTR_ERR(queue->ib_cq); + return ret; + } + + return 0; +} + static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue) { struct ib_device *ibdev; const int send_wr_factor = 3; /* MR, SEND, INV */ const int cq_factor = send_wr_factor + 1; /* + RECV */ - int comp_vector, idx = nvme_rdma_queue_idx(queue); - enum ib_poll_context poll_ctx; int ret, pages_per_mr; queue->device = nvme_rdma_find_get_device(queue->cm_id); @@ -467,26 +506,12 @@ static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue) } ibdev = queue->device->dev; - /* - * Spread I/O queues completion vectors according their queue index. - * Admin queues can always go on completion vector 0. - */ - comp_vector = (idx == 0 ? idx : idx - 1) % ibdev->num_comp_vectors; - - /* Polling queues need direct cq polling context */ - if (nvme_rdma_poll_queue(queue)) - poll_ctx = IB_POLL_DIRECT; - else - poll_ctx = IB_POLL_SOFTIRQ; - /* +1 for ib_stop_cq */ - queue->ib_cq = ib_alloc_cq(ibdev, queue, - cq_factor * queue->queue_size + 1, - comp_vector, poll_ctx); - if (IS_ERR(queue->ib_cq)) { - ret = PTR_ERR(queue->ib_cq); + queue->cq_size = cq_factor * queue->queue_size + 1; + + ret = nvme_rdma_create_cq(ibdev, queue); + if (ret) goto out_put_dev; - } ret = nvme_rdma_create_qp(queue, send_wr_factor); if (ret) @@ -512,7 +537,7 @@ static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue) if (ret) { dev_err(queue->ctrl->ctrl.device, "failed to initialize MR pool sized %d for QID %d\n", - queue->queue_size, idx); + queue->queue_size, nvme_rdma_queue_idx(queue)); goto out_destroy_ring; } @@ -523,7 +548,7 @@ static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue) if (ret) { dev_err(queue->ctrl->ctrl.device, "failed to initialize PI MR pool sized %d for QID %d\n", - queue->queue_size, idx); + queue->queue_size, nvme_rdma_queue_idx(queue)); goto out_destroy_mr_pool; } } @@ -540,7 +565,7 @@ out_destroy_ring: out_destroy_qp: rdma_destroy_qp(queue->cm_id); out_destroy_ib_cq: - ib_free_cq(queue->ib_cq); + nvme_rdma_free_cq(queue); out_put_dev: nvme_rdma_dev_put(queue->device); return ret; @@ -1163,7 +1188,7 @@ static void nvme_rdma_end_request(struct nvme_rdma_request *req) static void nvme_rdma_wr_error(struct ib_cq *cq, struct ib_wc *wc, const char *op) { - struct nvme_rdma_queue *queue = cq->cq_context; + struct nvme_rdma_queue *queue = wc->qp->qp_context; struct nvme_rdma_ctrl *ctrl = queue->ctrl; if (ctrl->ctrl.state == NVME_CTRL_LIVE) @@ -1706,7 +1731,7 @@ static void nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc) { struct nvme_rdma_qe *qe = container_of(wc->wr_cqe, struct nvme_rdma_qe, cqe); - struct nvme_rdma_queue *queue = cq->cq_context; + struct nvme_rdma_queue *queue = wc->qp->qp_context; struct ib_device *ibdev = queue->device->dev; struct nvme_completion *cqe = qe->data; const size_t len = sizeof(struct nvme_completion); -- 2.7.4