xprtrmda: Reduce lock contention in completion handlers
Skip the ib_poll_cq() after re-arming, if the provider knows there
are no additional items waiting. (Have a look at commit ed23a727 for
more details).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index af2d097..c7d5281 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -192,8 +192,11 @@
return;
}
- rc = ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
- if (rc) {
+ rc = ib_req_notify_cq(cq,
+ IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS);
+ if (rc == 0)
+ return;
+ if (rc < 0) {
dprintk("RPC: %s: ib_req_notify_cq failed: %i\n",
__func__, rc);
return;
@@ -272,8 +275,11 @@
return;
}
- rc = ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
- if (rc) {
+ rc = ib_req_notify_cq(cq,
+ IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS);
+ if (rc == 0)
+ return;
+ if (rc < 0) {
dprintk("RPC: %s: ib_req_notify_cq failed: %i\n",
__func__, rc);
return;