Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-ie0-f176.google.com ([209.85.223.176]:47157 "EHLO mail-ie0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753689AbaE1Odg (ORCPT ); Wed, 28 May 2014 10:33:36 -0400 From: Chuck Lever Subject: [PATCH v5 12/24] xprtrmda: Reduce lock contention in completion handlers To: linux-nfs@vger.kernel.org, linux-rdma@vger.kernel.org Cc: Anna.Schumaker@netapp.com Date: Wed, 28 May 2014 10:33:34 -0400 Message-ID: <20140528143334.23214.74603.stgit@manet.1015granger.net> In-Reply-To: <20140528142521.23214.39655.stgit@manet.1015granger.net> References: <20140528142521.23214.39655.stgit@manet.1015granger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: 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 --- net/sunrpc/xprtrdma/verbs.c | 14 ++++++++++---- 1 files changed, 10 insertions(+), 4 deletions(-) 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 @@ rpcrdma_sendcq_upcall(struct ib_cq *cq, void *cq_context) 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 @@ rpcrdma_recvcq_upcall(struct ib_cq *cq, void *cq_context) 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;