Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936626Ab3DHKXy (ORCPT ); Mon, 8 Apr 2013 06:23:54 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:42638 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935431Ab3DHJvR (ORCPT ); Mon, 8 Apr 2013 05:51:17 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Mike Marciniszyn , Roland Dreier , Luis Henriques Subject: [PATCH 011/102] IPoIB: Fix send lockup due to missed TX completion Date: Mon, 8 Apr 2013 10:49:26 +0100 Message-Id: <1365414657-29191-12-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1365414657-29191-1-git-send-email-luis.henriques@canonical.com> References: <1365414657-29191-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2321 Lines: 59 3.5.7.10 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Mike Marciniszyn commit 1ee9e2aa7b31427303466776f455d43e5e3c9275 upstream. Commit f0dc117abdfa ("IPoIB: Fix TX queue lockup with mixed UD/CM traffic") attempts to solve an issue where unprocessed UD send completions can deadlock the netdev. The patch doesn't fully resolve the issue because if more than half the tx_outstanding's were UD and all of the destinations are RC reachable, arming the CQ doesn't solve the issue. This patch uses the IB_CQ_REPORT_MISSED_EVENTS on the ib_req_notify_cq(). If the rc is above 0, the UD send cq completion callback is called directly to re-arm the send completion timer. This issue is seen in very large parallel filesystem deployments and the patch has been shown to correct the issue. Reviewed-by: Dean Luick Signed-off-by: Mike Marciniszyn Signed-off-by: Roland Dreier Signed-off-by: Luis Henriques --- drivers/infiniband/ulp/ipoib/ipoib_cm.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c index 014504d..3767853 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c @@ -755,9 +755,13 @@ void ipoib_cm_send(struct net_device *dev, struct sk_buff *skb, struct ipoib_cm_ if (++priv->tx_outstanding == ipoib_sendq_size) { ipoib_dbg(priv, "TX ring 0x%x full, stopping kernel net queue\n", tx->qp->qp_num); - if (ib_req_notify_cq(priv->send_cq, IB_CQ_NEXT_COMP)) - ipoib_warn(priv, "request notify on send CQ failed\n"); netif_stop_queue(dev); + rc = ib_req_notify_cq(priv->send_cq, + IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS); + if (rc < 0) + ipoib_warn(priv, "request notify on send CQ failed\n"); + else if (rc) + ipoib_send_comp_handler(priv->send_cq, dev); } } } -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/