From patchwork Tue Jul 18 07:57:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Markus Schneider-Pargmann X-Patchwork-Id: 13316845 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 241E7F512 for ; Tue, 18 Jul 2023 07:58:00 +0000 (UTC) Received: from mail-wr1-x42b.google.com (mail-wr1-x42b.google.com [IPv6:2a00:1450:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 777628E for ; Tue, 18 Jul 2023 00:57:29 -0700 (PDT) Received: by mail-wr1-x42b.google.com with SMTP id ffacd0b85a97d-3144098df56so5746013f8f.2 for ; Tue, 18 Jul 2023 00:57:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20221208.gappssmtp.com; s=20221208; t=1689667040; x=1690271840; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=5+cITQq+6DhgLZfrsuBe9J13n5cMEltSZ/UNHGZoGzo=; b=BoDZfUmE160ezuAbTAHahGEJhxwVXfpUk9zLbGxE47G2ktEKPRs+9YUiRc1BO00/KY dlfRAAe7KHNOl7PeFz4DavN0r3Y21SUvYuysC9vyPA4DnYQoq/s8axcMET80zD//v9nw BLqOISz1egdPc6EjbLwfqfF0vD7Q9tXyMb/rWUoIWN+qXlCS7xFAgdic5F3fpu0imAJE /qs+AzXRm5gzVI1GkX2S9RWyzpiR2QqG/HFE01jIU5Bb8PnTZFLTcoV74DziYjg+je3Z cUvye2ubgagCD4pv7gUWF2+udOo0F6LZA1t86/2CFO7ppbrkkVukNqvQE7uEjnnhwX4E yFKw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689667040; x=1690271840; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=5+cITQq+6DhgLZfrsuBe9J13n5cMEltSZ/UNHGZoGzo=; b=htx8IUSbYBFxevxQ8cLK7Yj5dEEnL/UXiOWxMCtb/HdyWO9sec0inuSELfysQiOVfW 5nJ+m1/noUcfwXylsvyh3j8csC56mzFtx9v2sRy0H3//ZUIeEYa3t96kV1vCX2aB1zbe O8jH1xwsQyNL0XbZ1HoFhl+5+UDhokEEYiB/SbT7h66dQKUNJXS7ro/WjVWgCQ458ECR N0mw4bleZYjBcC5rZhi10yyY54gWIdlSeHAM7518lPNmZrH3l09kXPGBoSh8TDFEMU1f hvqsJnxIcclAIXsY7FKbH36FuxmvWSx5s2uQsFSR44qHmfM9V2w5Ngx6wG4ZP/87b/9E qr3A== X-Gm-Message-State: ABy/qLZhiN3YbybamQU6B30o6TJohyj0lCIqgTxXO4uRcE8emrH1DhGU Hf+LvEKYL9ZfSFGB9qHbjLvvZg== X-Google-Smtp-Source: APBJJlEBQLJo6hWnVBuAtt+NO1wgrjcb2PcpF/vGv9+txyy9uDdLk1m5jZej0xNasx/04PduMpwSGg== X-Received: by 2002:a05:6000:18d:b0:314:4ba7:b024 with SMTP id p13-20020a056000018d00b003144ba7b024mr13883694wrx.9.1689667040622; Tue, 18 Jul 2023 00:57:20 -0700 (PDT) Received: from blmsp.fritz.box ([2001:4091:a247:82fa:b762:4f68:e1ed:5041]) by smtp.gmail.com with ESMTPSA id x4-20020a5d54c4000000b003142439c7bcsm1585959wrv.80.2023.07.18.00.57.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jul 2023 00:57:20 -0700 (PDT) From: Markus Schneider-Pargmann To: Marc Kleine-Budde , Chandrasekar Ramakrishnan , Wolfgang Grandegger Cc: Vincent MAILHOL , Simon Horman , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-can@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Julien Panis , Markus Schneider-Pargmann Subject: [PATCH v5 09/12] can: m_can: Introduce a tx_fifo_in_flight counter Date: Tue, 18 Jul 2023 09:57:05 +0200 Message-Id: <20230718075708.958094-10-msp@baylibre.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230718075708.958094-1-msp@baylibre.com> References: <20230718075708.958094-1-msp@baylibre.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org Keep track of the number of transmits in flight. This patch prepares the driver to control the network interface queue based on this counter. By itself this counter be implemented with an atomic, but as we need to do other things in the critical sections later I am using a spinlock instead. Signed-off-by: Markus Schneider-Pargmann Reviewed-by: Simon Horman --- drivers/net/can/m_can/m_can.c | 41 ++++++++++++++++++++++++++++++++++- drivers/net/can/m_can/m_can.h | 4 ++++ 2 files changed, 44 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index 9e4dcdfda59d..98ca5d13916b 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -465,6 +465,7 @@ static u32 m_can_get_timestamp(struct m_can_classdev *cdev) static void m_can_clean(struct net_device *net) { struct m_can_classdev *cdev = netdev_priv(net); + unsigned long irqflags; for (int i = 0; i != cdev->tx_fifo_size; ++i) { if (!cdev->tx_ops[i].skb) @@ -476,6 +477,10 @@ static void m_can_clean(struct net_device *net) for (int i = 0; i != cdev->can.echo_skb_max; ++i) can_free_echo_skb(cdev->net, i, NULL); + + spin_lock_irqsave(&cdev->tx_handling_spinlock, irqflags); + cdev->tx_fifo_in_flight = 0; + spin_unlock_irqrestore(&cdev->tx_handling_spinlock, irqflags); } /* For peripherals, pass skb to rx-offload, which will push skb from @@ -1046,6 +1051,24 @@ static void m_can_tx_update_stats(struct m_can_classdev *cdev, stats->tx_packets++; } +static void m_can_finish_tx(struct m_can_classdev *cdev, int transmitted) +{ + unsigned long irqflags; + + spin_lock_irqsave(&cdev->tx_handling_spinlock, irqflags); + cdev->tx_fifo_in_flight -= transmitted; + spin_unlock_irqrestore(&cdev->tx_handling_spinlock, irqflags); +} + +static void m_can_start_tx(struct m_can_classdev *cdev) +{ + unsigned long irqflags; + + spin_lock_irqsave(&cdev->tx_handling_spinlock, irqflags); + ++cdev->tx_fifo_in_flight; + spin_unlock_irqrestore(&cdev->tx_handling_spinlock, irqflags); +} + static int m_can_echo_tx_event(struct net_device *dev) { u32 txe_count = 0; @@ -1055,6 +1078,7 @@ static int m_can_echo_tx_event(struct net_device *dev) int i = 0; int err = 0; unsigned int msg_mark; + int processed = 0; struct m_can_classdev *cdev = netdev_priv(dev); @@ -1084,12 +1108,15 @@ static int m_can_echo_tx_event(struct net_device *dev) /* update stats */ m_can_tx_update_stats(cdev, msg_mark, timestamp); + ++processed; } if (ack_fgi != -1) m_can_write(cdev, M_CAN_TXEFA, FIELD_PREP(TXEFA_EFAI_MASK, ack_fgi)); + m_can_finish_tx(cdev, processed); + return err; } @@ -1168,6 +1195,7 @@ static irqreturn_t m_can_isr(int irq, void *dev_id) timestamp = m_can_get_timestamp(cdev); m_can_tx_update_stats(cdev, 0, timestamp); netif_wake_queue(dev); + m_can_finish_tx(cdev, 1); } } else { if (ir & (IR_TEFN | IR_TEFW)) { @@ -1853,11 +1881,22 @@ static netdev_tx_t m_can_start_peripheral_xmit(struct m_can_classdev *cdev, } netif_stop_queue(cdev->net); + + m_can_start_tx(cdev); + m_can_tx_queue_skb(cdev, skb); return NETDEV_TX_OK; } +static netdev_tx_t m_can_start_fast_xmit(struct m_can_classdev *cdev, + struct sk_buff *skb) +{ + m_can_start_tx(cdev); + + return m_can_tx_handler(cdev, skb); +} + static netdev_tx_t m_can_start_xmit(struct sk_buff *skb, struct net_device *dev) { @@ -1869,7 +1908,7 @@ static netdev_tx_t m_can_start_xmit(struct sk_buff *skb, if (cdev->is_peripheral) return m_can_start_peripheral_xmit(cdev, skb); else - return m_can_tx_handler(cdev, skb); + return m_can_start_fast_xmit(cdev, skb); } static int m_can_open(struct net_device *dev) diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h index 38b154fea04b..5c182aece15c 100644 --- a/drivers/net/can/m_can/m_can.h +++ b/drivers/net/can/m_can/m_can.h @@ -109,6 +109,10 @@ struct m_can_classdev { // Store this internally to avoid fetch delays on peripheral chips u32 tx_fifo_putidx; + /* Protects shared state between start_xmit and m_can_isr */ + spinlock_t tx_handling_spinlock; + int tx_fifo_in_flight; + struct m_can_tx_op *tx_ops; int tx_fifo_size; int next_tx_op;