IB/cma: Send MRA for reply messages

From: Moni Shoua <monis-VPRAkNaXOzVWk0Htik3J/[email protected]>

Current implementation of RDMA_CM sends MRA (Message Receipt Acknowledgment) only for request messages but not for response messages.

As a result, a slow active side of the connection may send a ready-to-use message to the passive side in a delay that is too long for the passive side to wait for.

This patch adds a call to ib_send_cm_mra() upon receiving a response message and by this tells the other side to modify the service timeout to a bigger value, 16 times than before. As in the request case, MRA for reply will be sent only if a duplicate response has arrived.

---
 drivers/infiniband/core/cma.c | 3 +++
 1 file changed, 3 insertions(+)

index acd10d666f1c..c1a90f0194f4 100644
@@ -1755,6 +1755,9 @@ static int cma_ib_handler(struct ib_cm_id *cm_id, struct ib_cm_event *ib_event)
 		event.status = -ETIMEDOUT;
 		break;
 	case IB_CM_REP_RECEIVED:
+		if (cma_comp(id_priv, RDMA_CM_CONNECT) &&
+		    (id_priv->id.qp_type != IB_QPT_UD))
+			ib_send_cm_mra(cm_id, CMA_CM_MRA_SETTING, NULL, 0);
 		if (id_priv->id.qp) {
 			event.status = cma_rep_recv(id_priv);
 			event.event = event.status ? RDMA_CM_EVENT_CONNECT_ERROR :

--
2.12.2

--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html

Thanks, applied.

Doug Ledford <[email protected]>
    GPG KeyID: B826A3330E572FDD
   
Key fingerprint = AE6B 1BDA 122B 23B4 265B  1274 B826 A333 0E57 2FDD

--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html