From: Devesh Sharma <devesh.sharma@avagotech.com>
Date: Tue, 20 Oct 2015 08:47:59 +0000 (+0530)
Subject: RDMA/ocrdma: Prevent CQ-Doorbell floods
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=af74d1956f780253d643a15f30d6aaa1c2e4836d;p=openwrt%2Fstaging%2Fblogic.git

RDMA/ocrdma: Prevent CQ-Doorbell floods

Changing CQ-Doorbell(DB) logic to prevent DB floods, it is supposed to be
pressed only if any hw CQE is polled. If cq-arm was requested
previously then don't bother about number of hw CQEs polled and
arm the CQ.

Signed-off-by: Devesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: Selvin Xavier <selvin.xavier@avagotech.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
---

diff --git a/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c b/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c
index 1f3affb6a477..1c4e83d5d153 100644
--- a/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c
+++ b/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c
@@ -2933,16 +2933,11 @@ expand_cqe:
 	}
 stop_cqe:
 	cq->getp = cur_getp;
-	if (cq->deferred_arm) {
-		ocrdma_ring_cq_db(dev, cq->id, true, cq->deferred_sol,
-				  polled_hw_cqes);
+	if (cq->deferred_arm || polled_hw_cqes) {
+		ocrdma_ring_cq_db(dev, cq->id, cq->deferred_arm,
+				  cq->deferred_sol, polled_hw_cqes);
 		cq->deferred_arm = false;
 		cq->deferred_sol = false;
-	} else {
-		/* We need to pop the CQE. No need to arm */
-		ocrdma_ring_cq_db(dev, cq->id, false, cq->deferred_sol,
-				  polled_hw_cqes);
-		cq->deferred_sol = false;
 	}
 
 	return i;