From patchwork Fri Jul 17 15:37:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Claudiu Manoil X-Patchwork-Id: 1331282 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=nxp.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4B7ZxW4RmHz9sR4 for ; Sat, 18 Jul 2020 01:37:19 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727844AbgGQPhS (ORCPT ); Fri, 17 Jul 2020 11:37:18 -0400 Received: from inva021.nxp.com ([92.121.34.21]:51684 "EHLO inva021.nxp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726998AbgGQPhH (ORCPT ); Fri, 17 Jul 2020 11:37:07 -0400 Received: from inva021.nxp.com (localhost [127.0.0.1]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 711A720097A; Fri, 17 Jul 2020 17:37:05 +0200 (CEST) Received: from inva024.eu-rdc02.nxp.com (inva024.eu-rdc02.nxp.com [134.27.226.22]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 6498020096D; Fri, 17 Jul 2020 17:37:05 +0200 (CEST) Received: from fsr-ub1664-016.ea.freescale.net (fsr-ub1664-016.ea.freescale.net [10.171.71.216]) by inva024.eu-rdc02.nxp.com (Postfix) with ESMTP id 37C2F20466; Fri, 17 Jul 2020 17:37:05 +0200 (CEST) From: Claudiu Manoil To: "David S . Miller" Cc: Jakub Kicinski , netdev@vger.kernel.org Subject: [PATCH net-next v2 2/6] enetc: Factor out the traffic start/stop procedures Date: Fri, 17 Jul 2020 18:37:00 +0300 Message-Id: <1595000224-6883-3-git-send-email-claudiu.manoil@nxp.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1595000224-6883-1-git-send-email-claudiu.manoil@nxp.com> References: <1595000224-6883-1-git-send-email-claudiu.manoil@nxp.com> X-Virus-Scanned: ClamAV using ClamSMTP Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org A reliable traffic pause (and reconfiguration) procedure is needed to be able to safely make h/w configuration changes during run-time, like changing the mode in which the interrupts are operating (i.e. with or without coalescing), as opposed to making on-the-fly register updates that may be subject to h/w or s/w concurrency issues. To this end, the code responsible of the run-time device configurations that basically starts resp. stops the traffic flow through the device has been extracted from the the enetc_open/_close procedures, to the separate standalone enetc_start/_stop procedures. Traffic stop should be as graceful as possible, it lets the executing napi threads to to finish while the interrupts stay disabled. But since the napi thread will try to re-enable interrupts by clearing the device's unmask register, the enable_irq/ disable_irq API has been used to avoid this potential concurrency issue and make the traffic pause procedure more reliable. Signed-off-by: Claudiu Manoil --- v2: none drivers/net/ethernet/freescale/enetc/enetc.c | 74 +++++++++++++------- 1 file changed, 49 insertions(+), 25 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index d91e52618681..51a1c97aedac 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -1264,6 +1264,7 @@ static int enetc_setup_irqs(struct enetc_ndev_priv *priv) dev_err(priv->dev, "request_irq() failed!\n"); goto irq_err; } + disable_irq(irq); v->tbier_base = hw->reg + ENETC_BDR(TX, 0, ENETC_TBIER); v->rbier = hw->reg + ENETC_BDR(RX, i, ENETC_RBIER); @@ -1306,7 +1307,7 @@ static void enetc_free_irqs(struct enetc_ndev_priv *priv) } } -static void enetc_enable_interrupts(struct enetc_ndev_priv *priv) +static void enetc_setup_interrupts(struct enetc_ndev_priv *priv) { int i; @@ -1322,7 +1323,7 @@ static void enetc_enable_interrupts(struct enetc_ndev_priv *priv) } } -static void enetc_disable_interrupts(struct enetc_ndev_priv *priv) +static void enetc_clear_interrupts(struct enetc_ndev_priv *priv) { int i; @@ -1369,10 +1370,33 @@ static int enetc_phy_connect(struct net_device *ndev) return 0; } +static void enetc_start(struct net_device *ndev) +{ + struct enetc_ndev_priv *priv = netdev_priv(ndev); + int i; + + enetc_setup_interrupts(priv); + + for (i = 0; i < priv->bdr_int_num; i++) { + int irq = pci_irq_vector(priv->si->pdev, + ENETC_BDR_INT_BASE_IDX + i); + + napi_enable(&priv->int_vector[i]->napi); + enable_irq(irq); + } + + if (ndev->phydev) + phy_start(ndev->phydev); + else + netif_carrier_on(ndev); + + netif_tx_start_all_queues(ndev); +} + int enetc_open(struct net_device *ndev) { struct enetc_ndev_priv *priv = netdev_priv(ndev); - int i, err; + int err; err = enetc_setup_irqs(priv); if (err) @@ -1390,8 +1414,6 @@ int enetc_open(struct net_device *ndev) if (err) goto err_alloc_rx; - enetc_setup_bdrs(priv); - err = netif_set_real_num_tx_queues(ndev, priv->num_tx_rings); if (err) goto err_set_queues; @@ -1400,17 +1422,8 @@ int enetc_open(struct net_device *ndev) if (err) goto err_set_queues; - for (i = 0; i < priv->bdr_int_num; i++) - napi_enable(&priv->int_vector[i]->napi); - - enetc_enable_interrupts(priv); - - if (ndev->phydev) - phy_start(ndev->phydev); - else - netif_carrier_on(ndev); - - netif_tx_start_all_queues(ndev); + enetc_setup_bdrs(priv); + enetc_start(ndev); return 0; @@ -1427,28 +1440,39 @@ int enetc_open(struct net_device *ndev) return err; } -int enetc_close(struct net_device *ndev) +static void enetc_stop(struct net_device *ndev) { struct enetc_ndev_priv *priv = netdev_priv(ndev); int i; netif_tx_stop_all_queues(ndev); - if (ndev->phydev) { - phy_stop(ndev->phydev); - phy_disconnect(ndev->phydev); - } else { - netif_carrier_off(ndev); - } - for (i = 0; i < priv->bdr_int_num; i++) { + int irq = pci_irq_vector(priv->si->pdev, + ENETC_BDR_INT_BASE_IDX + i); + + disable_irq(irq); napi_synchronize(&priv->int_vector[i]->napi); napi_disable(&priv->int_vector[i]->napi); } - enetc_disable_interrupts(priv); + if (ndev->phydev) + phy_stop(ndev->phydev); + else + netif_carrier_off(ndev); + + enetc_clear_interrupts(priv); +} + +int enetc_close(struct net_device *ndev) +{ + struct enetc_ndev_priv *priv = netdev_priv(ndev); + + enetc_stop(ndev); enetc_clear_bdrs(priv); + if (ndev->phydev) + phy_disconnect(ndev->phydev); enetc_free_rxtx_rings(priv); enetc_free_rx_resources(priv); enetc_free_tx_resources(priv);