IPoIB: Use separate CQ for UD send completions

Use a dedicated CQ for UD send completions. Also, do not arm the UD
send CQ, which reduces the number of interrupts generated.  This patch
farther reduces overhead by not calling poll CQ for every posted send
WR -- it does polls only when there 16 or more outstanding work requests.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 26 insertions, 13 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_verbs.c b/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
index 07c03f178a49..c1e7ece1fd44 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
@@ -171,26 +171,33 @@ int ipoib_transport_dev_init(struct net_device *dev, struct ib_device *ca)
 		goto out_free_pd;
 	}
 
-	size = ipoib_sendq_size + ipoib_recvq_size + 1;
+	size = ipoib_recvq_size + 1;
 	ret = ipoib_cm_dev_init(dev);
 	if (!ret) {
+		size += ipoib_sendq_size;
 		if (ipoib_cm_has_srq(dev))
 			size += ipoib_recvq_size + 1; /* 1 extra for rx_drain_qp */
 		else
 			size += ipoib_recvq_size * ipoib_max_conn_qp;
 	}
 
-	priv->cq = ib_create_cq(priv->ca, ipoib_ib_completion, NULL, dev, size, 0);
-	if (IS_ERR(priv->cq)) {
-		printk(KERN_WARNING "%s: failed to create CQ\n", ca->name);
+	priv->recv_cq = ib_create_cq(priv->ca, ipoib_ib_completion, NULL, dev, size, 0);
+	if (IS_ERR(priv->recv_cq)) {
+		printk(KERN_WARNING "%s: failed to create receive CQ\n", ca->name);
 		goto out_free_mr;
 	}
 
-	if (ib_req_notify_cq(priv->cq, IB_CQ_NEXT_COMP))
-		goto out_free_cq;
+	priv->send_cq = ib_create_cq(priv->ca, NULL, NULL, dev, ipoib_sendq_size, 0);
+	if (IS_ERR(priv->send_cq)) {
+		printk(KERN_WARNING "%s: failed to create send CQ\n", ca->name);
+		goto out_free_recv_cq;
+	}
+
+	if (ib_req_notify_cq(priv->recv_cq, IB_CQ_NEXT_COMP))
+		goto out_free_send_cq;
 
-	init_attr.send_cq = priv->cq;
-	init_attr.recv_cq = priv->cq;
+	init_attr.send_cq = priv->send_cq;
+	init_attr.recv_cq = priv->recv_cq;
 
 	if (priv->hca_caps & IB_DEVICE_UD_TSO)
 		init_attr.create_flags = IB_QP_CREATE_IPOIB_UD_LSO;
@@ -201,7 +208,7 @@ int ipoib_transport_dev_init(struct net_device *dev, struct ib_device *ca)
 	priv->qp = ib_create_qp(priv->pd, &init_attr);
 	if (IS_ERR(priv->qp)) {
 		printk(KERN_WARNING "%s: failed to create QP\n", ca->name);
-		goto out_free_cq;
+		goto out_free_send_cq;
 	}
 
 	priv->dev->dev_addr[1] = (priv->qp->qp_num >> 16) & 0xff;
@@ -230,8 +237,11 @@ int ipoib_transport_dev_init(struct net_device *dev, struct ib_device *ca)
 
 	return 0;
 
-out_free_cq:
-	ib_destroy_cq(priv->cq);
+out_free_send_cq:
+	ib_destroy_cq(priv->send_cq);
+
+out_free_recv_cq:
+	ib_destroy_cq(priv->recv_cq);
 
 out_free_mr:
 	ib_dereg_mr(priv->mr);
@@ -254,8 +264,11 @@ void ipoib_transport_dev_cleanup(struct net_device *dev)
 		clear_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
 	}
 
-	if (ib_destroy_cq(priv->cq))
-		ipoib_warn(priv, "ib_cq_destroy failed\n");
+	if (ib_destroy_cq(priv->send_cq))
+		ipoib_warn(priv, "ib_cq_destroy (send) failed\n");
+
+	if (ib_destroy_cq(priv->recv_cq))
+		ipoib_warn(priv, "ib_cq_destroy (recv) failed\n");
 
 	ipoib_cm_dev_cleanup(dev);