From mboxrd@z Thu Jan 1 00:00:00 1970 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=unavailable 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 78069C4320A for ; Thu, 19 Aug 2021 13:40:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6720A610CF for ; Thu, 19 Aug 2021 13:40:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240362AbhHSNkf (ORCPT ); Thu, 19 Aug 2021 09:40:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240278AbhHSNkZ (ORCPT ); Thu, 19 Aug 2021 09:40:25 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B6C7CC0612A5 for ; Thu, 19 Aug 2021 06:39:45 -0700 (PDT) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mGiGm-00058R-2p for linux-can@vger.kernel.org; Thu, 19 Aug 2021 15:39:44 +0200 Received: from dspam.blackshift.org (localhost [127.0.0.1]) by bjornoya.blackshift.org (Postfix) with SMTP id A6F9566A895 for ; Thu, 19 Aug 2021 13:39:36 +0000 (UTC) Received: from hardanger.blackshift.org (unknown [172.20.34.65]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by bjornoya.blackshift.org (Postfix) with ESMTPS id D1E0A66A848; Thu, 19 Aug 2021 13:39:28 +0000 (UTC) Received: from blackshift.org (localhost [::1]) by hardanger.blackshift.org (OpenSMTPD) with ESMTP id d512e25b; Thu, 19 Aug 2021 13:39:16 +0000 (UTC) From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, linux-can@vger.kernel.org, kernel@pengutronix.de, Dario Binacchi , Marc Kleine-Budde Subject: [PATCH net-next 20/22] can: c_can: exit c_can_do_tx() early if no frames have been sent Date: Thu, 19 Aug 2021 15:39:11 +0200 Message-Id: <20210819133913.657715-21-mkl@pengutronix.de> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210819133913.657715-1-mkl@pengutronix.de> References: <20210819133913.657715-1-mkl@pengutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-can@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org From: Dario Binacchi The c_can_poll() handles RX/TX events unconditionally. It may therefore happen that c_can_do_tx() is called unnecessarily because the interrupt was triggered by the reception of a frame. In these cases, we avoid to execute unnecessary statements and exit immediately. Link: https://lore.kernel.org/r/20210807130800.5246-3-dariobin@libero.it Signed-off-by: Dario Binacchi Signed-off-by: Marc Kleine-Budde --- drivers/net/can/c_can/c_can_main.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/net/can/c_can/c_can_main.c b/drivers/net/can/c_can/c_can_main.c index 052ff35ed4dc..1ec0ce664732 100644 --- a/drivers/net/can/c_can/c_can_main.c +++ b/drivers/net/can/c_can/c_can_main.c @@ -720,17 +720,18 @@ static void c_can_do_tx(struct net_device *dev) pkts++; } + if (!pkts) + return; + /* Clear the bits in the tx_active mask */ atomic_sub(clr, &priv->tx_active); if (clr & BIT(priv->msg_obj_tx_num - 1)) netif_wake_queue(dev); - if (pkts) { - stats->tx_bytes += bytes; - stats->tx_packets += pkts; - can_led_event(dev, CAN_LED_EVENT_TX); - } + stats->tx_bytes += bytes; + stats->tx_packets += pkts; + can_led_event(dev, CAN_LED_EVENT_TX); } /* If we have a gap in the pending bits, that means we either -- 2.32.0