IB/ipath: Improve UD loopback performance by allocating temp array only once

Receive work queue entries are checked for L_Key validity, and
pointers to the memory region structure are saved in an allocated
structure.  For UD loopback packets, this structure is allocated and
freed for each packet.  This patch changes that to allocate/free
during QP creation and destruction.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 24 insertions, 8 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_qp.c b/drivers/infiniband/hw/ipath/ipath_qp.c
index 4715911101e4..3a5a89b609c4 100644
--- a/drivers/infiniband/hw/ipath/ipath_qp.c
+++ b/drivers/infiniband/hw/ipath/ipath_qp.c
@@ -745,6 +745,7 @@ struct ib_qp *ipath_create_qp(struct ib_pd *ibpd,
 	struct ipath_swqe *swq = NULL;
 	struct ipath_ibdev *dev;
 	size_t sz;
+	size_t sg_list_sz;
 	struct ib_qp *ret;
 
 	if (init_attr->create_flags) {
@@ -789,19 +790,31 @@ struct ib_qp *ipath_create_qp(struct ib_pd *ibpd,
 			goto bail;
 		}
 		sz = sizeof(*qp);
+		sg_list_sz = 0;
 		if (init_attr->srq) {
 			struct ipath_srq *srq = to_isrq(init_attr->srq);
 
-			sz += sizeof(*qp->r_sg_list) *
-				srq->rq.max_sge;
-		} else
-			sz += sizeof(*qp->r_sg_list) *
-				init_attr->cap.max_recv_sge;
-		qp = kmalloc(sz, GFP_KERNEL);
+			if (srq->rq.max_sge > 1)
+				sg_list_sz = sizeof(*qp->r_sg_list) *
+					(srq->rq.max_sge - 1);
+		} else if (init_attr->cap.max_recv_sge > 1)
+			sg_list_sz = sizeof(*qp->r_sg_list) *
+				(init_attr->cap.max_recv_sge - 1);
+		qp = kmalloc(sz + sg_list_sz, GFP_KERNEL);
 		if (!qp) {
 			ret = ERR_PTR(-ENOMEM);
 			goto bail_swq;
 		}
+		if (sg_list_sz && (init_attr->qp_type == IB_QPT_UD ||
+		    init_attr->qp_type == IB_QPT_SMI ||
+		    init_attr->qp_type == IB_QPT_GSI)) {
+			qp->r_ud_sg_list = kmalloc(sg_list_sz, GFP_KERNEL);
+			if (!qp->r_ud_sg_list) {
+				ret = ERR_PTR(-ENOMEM);
+				goto bail_qp;
+			}
+		} else
+			qp->r_ud_sg_list = NULL;
 		if (init_attr->srq) {
 			sz = 0;
 			qp->r_rq.size = 0;
@@ -818,7 +831,7 @@ struct ib_qp *ipath_create_qp(struct ib_pd *ibpd,
 					      qp->r_rq.size * sz);
 			if (!qp->r_rq.wq) {
 				ret = ERR_PTR(-ENOMEM);
-				goto bail_qp;
+				goto bail_sg_list;
 			}
 		}
 
@@ -848,7 +861,7 @@ struct ib_qp *ipath_create_qp(struct ib_pd *ibpd,
 		if (err) {
 			ret = ERR_PTR(err);
 			vfree(qp->r_rq.wq);
-			goto bail_qp;
+			goto bail_sg_list;
 		}
 		qp->ip = NULL;
 		qp->s_tx = NULL;
@@ -925,6 +938,8 @@ bail_ip:
 		vfree(qp->r_rq.wq);
 	ipath_free_qp(&dev->qp_table, qp);
 	free_qpn(&dev->qp_table, qp->ibqp.qp_num);
+bail_sg_list:
+	kfree(qp->r_ud_sg_list);
 bail_qp:
 	kfree(qp);
 bail_swq:
@@ -989,6 +1004,7 @@ int ipath_destroy_qp(struct ib_qp *ibqp)
 		kref_put(&qp->ip->ref, ipath_release_mmap_info);
 	else
 		vfree(qp->r_rq.wq);
+	kfree(qp->r_ud_sg_list);
 	vfree(qp->s_wq);
 	kfree(qp);
 	return 0;