From patchwork Tue Apr 13 03:48:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yangbo Lu X-Patchwork-Id: 12199213 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8CFEAC433B4 for ; Tue, 13 Apr 2021 03:41:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 67770611C9 for ; Tue, 13 Apr 2021 03:41:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241668AbhDMDmL (ORCPT ); Mon, 12 Apr 2021 23:42:11 -0400 Received: from inva020.nxp.com ([92.121.34.13]:33536 "EHLO inva020.nxp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237526AbhDMDmK (ORCPT ); Mon, 12 Apr 2021 23:42:10 -0400 Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id DD8321A21D8; Tue, 13 Apr 2021 05:41:50 +0200 (CEST) Received: from invc005.ap-rdc01.nxp.com (invc005.ap-rdc01.nxp.com [165.114.16.14]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 87F121A0DD8; Tue, 13 Apr 2021 05:41:47 +0200 (CEST) Received: from localhost.localdomain (mega.ap.freescale.net [10.192.208.232]) by invc005.ap-rdc01.nxp.com (Postfix) with ESMTP id 06A86402CF; Tue, 13 Apr 2021 05:41:42 +0200 (CEST) From: Yangbo Lu To: netdev@vger.kernel.org Cc: Yangbo Lu , "David S . Miller" , Richard Cochran , Claudiu Manoil , Jakub Kicinski , Vladimir Oltean , Russell King Subject: [net-next] enetc: fix locking for one-step timestamping packet transfer Date: Tue, 13 Apr 2021 11:48:17 +0800 Message-Id: <20210413034817.8924-1-yangbo.lu@nxp.com> X-Mailer: git-send-email 2.17.1 X-Virus-Scanned: ClamAV using ClamSMTP Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org The previous patch to support PTP Sync packet one-step timestamping described one-step timestamping packet handling logic as below in commit message: - Trasmit packet immediately if no other one in transfer, or queue to skb queue if there is already one in transfer. The test_and_set_bit_lock() is used here to lock and check state. - Start a work when complete transfer on hardware, to release the bit lock and to send one skb in skb queue if has. There was not problem of the description, but there was a mistake in implementation. The locking/test_and_set_bit_lock() should be put in enetc_start_xmit() which may be called by worker, rather than in enetc_xmit(). Otherwise, the worker calling enetc_start_xmit() after bit lock released is not able to lock again for transfer. Fixes: 7294380c5211 ("enetc: support PTP Sync packet one-step timestamping") Signed-off-by: Yangbo Lu Reviewed-by: Claudiu Manoil --- drivers/net/ethernet/freescale/enetc/enetc.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) base-commit: 8ef7adc6beb2ef0bce83513dc9e4505e7b21e8c2 diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index 4a0adb0b8bd7..65f1772c5740 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -301,6 +301,15 @@ static netdev_tx_t enetc_start_xmit(struct sk_buff *skb, struct enetc_bdr *tx_ring; int count; + /* Queue one-step Sync packet if already locked */ + if (skb->cb[0] & ENETC_F_TX_ONESTEP_SYNC_TSTAMP) { + if (test_and_set_bit_lock(ENETC_TX_ONESTEP_TSTAMP_IN_PROGRESS, + &priv->flags)) { + skb_queue_tail(&priv->tx_skbs, skb); + return NETDEV_TX_OK; + } + } + tx_ring = priv->tx_ring[skb->queue_mapping]; if (unlikely(skb_shinfo(skb)->nr_frags > ENETC_MAX_SKB_FRAGS)) @@ -352,15 +361,6 @@ netdev_tx_t enetc_xmit(struct sk_buff *skb, struct net_device *ndev) skb->cb[0] = ENETC_F_TX_TSTAMP; } - /* Queue one-step Sync packet if already locked */ - if (skb->cb[0] & ENETC_F_TX_ONESTEP_SYNC_TSTAMP) { - if (test_and_set_bit_lock(ENETC_TX_ONESTEP_TSTAMP_IN_PROGRESS, - &priv->flags)) { - skb_queue_tail(&priv->tx_skbs, skb); - return NETDEV_TX_OK; - } - } - return enetc_start_xmit(skb, ndev); }