nvme_rdma: Get qpair from poll group using WC

NVMe-RDMA target has a helper function get_rdma_qpair_from_wc() and
uses it to identify a qpair from a WC.

NVMe-RDMA initiator has a similar function
nvme_rdma_poll_group_get_qpair_by_id().

NVMe-RDMA initiator will support SRQ in the following patches, and
it will want to identify a qpair from a WC.

get_rdma_qpair_from_wc() of NVMe-RDMA target uses wc->qp_num internally
anyway.

However, the upcoming custom transport for RDMA will have to use other
variables of WC.

Hence, it will be convenient to pass WC instead of qp_num if we consider
future enhancements.

Based on these thoughts, for NVMe-RDMA initiator rename
nvme_rdma_poll_group_get_qpair_by_id() by get_rdma_qpair_from_wc().
remove unnecessary declaration, and pass WC instead of qp_num.

Signed-off-by: Shuhei Matsumoto <smatsumoto@nvidia.com>
Signed-off-by: Denis Nagorny <denisn@nvidia.com>
Signed-off-by: Evgeniy Kochetov <evgeniik@nvidia.com>
Change-Id: I01ead4730207e2c6ac53b83f151bd5f977a11465
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/14279
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Aleksey Marchuk <alexeymar@nvidia.com>

lib/nvme/nvme_rdma.c

@@ -279,8 +279,6 @@ static const char *rdma_cm_event_str[] = {
 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
 };
 
-struct nvme_rdma_qpair *nvme_rdma_poll_group_get_qpair_by_id(struct nvme_rdma_poll_group *group,
-		uint32_t qp_num);
 static struct nvme_rdma_poller *nvme_rdma_poll_group_get_poller(struct nvme_rdma_poll_group *group,
 		struct ibv_context *device);
 static void nvme_rdma_poll_group_put_poller(struct nvme_rdma_poll_group *group,
@@ -2393,6 +2391,29 @@ nvme_rdma_fail_qpair(struct spdk_nvme_qpair *qpair, int failure_reason)
 	nvme_ctrlr_disconnect_qpair(qpair);
 }
 
+static struct nvme_rdma_qpair *
+get_rdma_qpair_from_wc(struct nvme_rdma_poll_group *group, struct ibv_wc *wc)
+{
+	struct spdk_nvme_qpair *qpair;
+	struct nvme_rdma_qpair *rqpair;
+
+	STAILQ_FOREACH(qpair, &group->group.connected_qpairs, poll_group_stailq) {
+		rqpair = nvme_rdma_qpair(qpair);
+		if (NVME_RDMA_POLL_GROUP_CHECK_QPN(rqpair, wc->qp_num)) {
+			return rqpair;
+		}
+	}
+
+	STAILQ_FOREACH(qpair, &group->group.disconnected_qpairs, poll_group_stailq) {
+		rqpair = nvme_rdma_qpair(qpair);
+		if (NVME_RDMA_POLL_GROUP_CHECK_QPN(rqpair, wc->qp_num)) {
+			return rqpair;
+		}
+	}
+
+	return NULL;
+}
+
 static inline void
 nvme_rdma_log_wc_status(struct nvme_rdma_qpair *rqpair, struct ibv_wc *wc)
 {
@@ -2489,8 +2510,7 @@ nvme_rdma_cq_process_completions(struct ibv_cq *cq, uint32_t batch_size,
 			if (wc[i].status) {
 				rqpair = rdma_req->req ? nvme_rdma_qpair(rdma_req->req->qpair) : NULL;
 				if (!rqpair) {
-					rqpair = rdma_qpair != NULL ? rdma_qpair : nvme_rdma_poll_group_get_qpair_by_id(group,
+					rqpair = rdma_qpair != NULL ? rdma_qpair : get_rdma_qpair_from_wc(group, &wc[i]);
-							wc[i].qp_num);
 				}
 				if (!rqpair) {
 					/* When poll_group is used, several qpairs share the same CQ and it is possible to
@@ -2838,30 +2858,6 @@ nvme_rdma_poll_group_create(void)
 	return &group->group;
 }
 
-struct nvme_rdma_qpair *
-nvme_rdma_poll_group_get_qpair_by_id(struct nvme_rdma_poll_group *group, uint32_t qp_num)
-{
-	struct spdk_nvme_qpair *qpair;
-	struct nvme_rdma_qpair *rqpair;
-
-	STAILQ_FOREACH(qpair, &group->group.disconnected_qpairs, poll_group_stailq) {
-		rqpair = nvme_rdma_qpair(qpair);
-		if (NVME_RDMA_POLL_GROUP_CHECK_QPN(rqpair, qp_num)) {
-			return rqpair;
-		}
-	}
-
-	STAILQ_FOREACH(qpair, &group->group.connected_qpairs, poll_group_stailq) {
-		rqpair = nvme_rdma_qpair(qpair);
-		if (NVME_RDMA_POLL_GROUP_CHECK_QPN(rqpair, qp_num)) {
-			return rqpair;
-		}
-	}
-
-	return NULL;
-}
-
-
 static int
 nvme_rdma_poll_group_connect_qpair(struct spdk_nvme_qpair *qpair)
 {

test/unit/lib/nvme/nvme_rdma.c/nvme_rdma_ut.c

@@ -1236,26 +1236,27 @@ test_rdma_get_memory_translation(void)
 }
 
 static void
-test_nvme_rdma_poll_group_get_qpair_by_id(void)
+test_get_rdma_qpair_from_wc(void)
 {
 	const uint32_t test_qp_num = 123;
 	struct nvme_rdma_poll_group	group = {};
 	struct nvme_rdma_qpair rqpair = {};
 	struct spdk_rdma_qp rdma_qp = {};
 	struct ibv_qp qp = { .qp_num = test_qp_num };
+	struct ibv_wc wc = { .qp_num = test_qp_num };
 
 	STAILQ_INIT(&group.group.disconnected_qpairs);
 	STAILQ_INIT(&group.group.connected_qpairs);
 	rqpair.qpair.trtype = SPDK_NVME_TRANSPORT_RDMA;
 
 	/* Test 1 - Simulate case when nvme_rdma_qpair is disconnected but still in one of lists.
-	 * nvme_rdma_poll_group_get_qpair_by_id must return NULL */
+	 * get_rdma_qpair_from_wc must return NULL */
 	STAILQ_INSERT_HEAD(&group.group.disconnected_qpairs, &rqpair.qpair, poll_group_stailq);
-	CU_ASSERT(nvme_rdma_poll_group_get_qpair_by_id(&group, test_qp_num) == NULL);
+	CU_ASSERT(get_rdma_qpair_from_wc(&group, &wc) == NULL);
 	STAILQ_REMOVE_HEAD(&group.group.disconnected_qpairs, poll_group_stailq);
 
 	STAILQ_INSERT_HEAD(&group.group.connected_qpairs, &rqpair.qpair, poll_group_stailq);
-	CU_ASSERT(nvme_rdma_poll_group_get_qpair_by_id(&group, test_qp_num) == NULL);
+	CU_ASSERT(get_rdma_qpair_from_wc(&group, &wc) == NULL);
 	STAILQ_REMOVE_HEAD(&group.group.connected_qpairs, poll_group_stailq);
 
 	/* Test 2 - nvme_rdma_qpair with valid rdma_qp/ibv_qp and qp_num */
@@ -1263,11 +1264,11 @@ test_nvme_rdma_poll_group_get_qpair_by_id(void)
 	rqpair.rdma_qp = &rdma_qp;
 
 	STAILQ_INSERT_HEAD(&group.group.disconnected_qpairs, &rqpair.qpair, poll_group_stailq);
-	CU_ASSERT(nvme_rdma_poll_group_get_qpair_by_id(&group, test_qp_num) == &rqpair);
+	CU_ASSERT(get_rdma_qpair_from_wc(&group, &wc) == &rqpair);
 	STAILQ_REMOVE_HEAD(&group.group.disconnected_qpairs, poll_group_stailq);
 
 	STAILQ_INSERT_HEAD(&group.group.connected_qpairs, &rqpair.qpair, poll_group_stailq);
-	CU_ASSERT(nvme_rdma_poll_group_get_qpair_by_id(&group, test_qp_num) == &rqpair);
+	CU_ASSERT(get_rdma_qpair_from_wc(&group, &wc) == &rqpair);
 	STAILQ_REMOVE_HEAD(&group.group.connected_qpairs, poll_group_stailq);
 }
 
@@ -1524,7 +1525,7 @@ main(int argc, char **argv)
 	CU_ADD_TEST(suite, test_nvme_rdma_memory_domain);
 	CU_ADD_TEST(suite, test_rdma_ctrlr_get_memory_domains);
 	CU_ADD_TEST(suite, test_rdma_get_memory_translation);
-	CU_ADD_TEST(suite, test_nvme_rdma_poll_group_get_qpair_by_id);
+	CU_ADD_TEST(suite, test_get_rdma_qpair_from_wc);
 	CU_ADD_TEST(suite, test_nvme_rdma_ctrlr_get_max_sges);
 	CU_ADD_TEST(suite, test_nvme_rdma_poll_group_get_stats);
 	CU_ADD_TEST(suite, test_nvme_rdma_poll_group_set_cq);