[PATCH v2 2/2] nvmet-rdma: add unbound_wq support for nvmet-rdma

[Ping Gan]

To define a module parameter use_unbound_wq to enable unbound
workqueue to handle RDMA's IO of CQ.

Signed-off-by: Ping Gan <jacky_gam_2001 at 163.com>
Reviewed-by: Hannes Reinecke <hare at suse.de>
---
 drivers/nvme/target/rdma.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c
index 1eff8ca6a5f1..bfd7106316bc 100644
--- a/drivers/nvme/target/rdma.c
+++ b/drivers/nvme/target/rdma.c
@@ -155,6 +155,10 @@ static int nvmet_rdma_srq_size = 1024;
 module_param_cb(srq_size, &srq_size_ops, &nvmet_rdma_srq_size, 0644);
 MODULE_PARM_DESC(srq_size, "set Shared Receive Queue (SRQ) size, should >= 256 (default: 1024)");
 
+static bool use_unbound_wq;
+module_param(use_unbound_wq, bool, 0444);
+MODULE_PARM_DESC(use_unbound_wq, "use unbound workqueue to handle IO request: Default false");
+
 static DEFINE_IDA(nvmet_rdma_queue_ida);
 static LIST_HEAD(nvmet_rdma_queue_list);
 static DEFINE_MUTEX(nvmet_rdma_queue_mutex);
@@ -1259,7 +1263,11 @@ static int nvmet_rdma_create_queue_ib(struct nvmet_rdma_queue *queue)
 	 */
 	nr_cqe = queue->recv_queue_size + 2 * queue->send_queue_size;
 
-	queue->cq = ib_cq_pool_get(ndev->device, nr_cqe + 1,
+	if (use_unbound_wq)
+		queue->cq = ib_cq_pool_get(ndev->device, nr_cqe + 1,
+				   queue->comp_vector, IB_POLL_UNBOUND_WORKQUEUE);
+	else
+		queue->cq = ib_cq_pool_get(ndev->device, nr_cqe + 1,
 				   queue->comp_vector, IB_POLL_WORKQUEUE);
 	if (IS_ERR(queue->cq)) {
 		ret = PTR_ERR(queue->cq);
-- 
2.26.2