[PATCH 1/3] nvme-rdma: use new shared CQ mechanism
Max Gurtovoy
maxg at mellanox.com
Tue Jun 23 10:55:23 EDT 2020
From: Yamin Friedman <yaminf at mellanox.com>
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 <yaminf at mellanox.com>
Signed-off-by: Max Gurtovoy <maxg at mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz at mellanox.com>
Reviewed-by: Sagi Grimberg <sagi at grimberg.me>
---
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 f8f856d..f5d6a57 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 {
@@ -274,6 +275,7 @@ 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);
@@ -408,6 +410,14 @@ static int nvme_rdma_dev_get(struct nvme_rdma_device *dev)
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;
@@ -429,7 +439,7 @@ 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);
@@ -449,13 +459,42 @@ 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;
+
+ /* 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);
@@ -466,26 +505,12 @@ 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;
-
- /* 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)
@@ -511,7 +536,7 @@ 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;
}
@@ -522,7 +547,7 @@ 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;
}
}
@@ -539,7 +564,7 @@ static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue)
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;
@@ -1152,7 +1177,7 @@ static void nvme_rdma_error_recovery(struct nvme_rdma_ctrl *ctrl)
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)
@@ -1705,7 +1730,7 @@ 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);
--
1.8.3.1
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