From patchwork Tue Mar 24 13:23:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andre Przywara X-Patchwork-Id: 221969 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, 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 7F5B5C2BAEE for ; Tue, 24 Mar 2020 13:29:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5823C208D5 for ; Tue, 24 Mar 2020 13:29:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727337AbgCXN3n (ORCPT ); Tue, 24 Mar 2020 09:29:43 -0400 Received: from foss.arm.com ([217.140.110.172]:34492 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727720AbgCXNX6 (ORCPT ); Tue, 24 Mar 2020 09:23:58 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 615181045; Tue, 24 Mar 2020 06:23:57 -0700 (PDT) Received: from donnerap.arm.com (donnerap.cambridge.arm.com [10.1.197.25]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 133A83F52E; Tue, 24 Mar 2020 06:23:55 -0700 (PDT) From: Andre Przywara To: "David S . Miller" , Radhey Shyam Pandey Cc: Michal Simek , Robert Hancock , netdev@vger.kernel.org, Russell King , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Andrew Lunn Subject: [PATCH v3 02/14] net: axienet: Convert DMA error handler to a work queue Date: Tue, 24 Mar 2020 13:23:35 +0000 Message-Id: <20200324132347.23709-3-andre.przywara@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200324132347.23709-1-andre.przywara@arm.com> References: <20200324132347.23709-1-andre.przywara@arm.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The DMA error handler routine is currently a tasklet, scheduled to run after the DMA error IRQ was handled. However it needs to take the MDIO mutex, which is not allowed to do in a tasklet. A kernel (with debug options) complains consequently: [ 614.050361] net eth0: DMA Tx error 0x174019 [ 614.064002] net eth0: Current BD is at: 0x8f84aa0ce [ 614.080195] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935 [ 614.109484] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 40, name: kworker/u4:4 [ 614.135428] 3 locks held by kworker/u4:4/40: [ 614.149075] #0: ffff000879863328 ((wq_completion)rpciod){....}, at: process_one_work+0x1f0/0x6a8 [ 614.177528] #1: ffff80001251bdf8 ((work_completion)(&task->u.tk_work)){....}, at: process_one_work+0x1f0/0x6a8 [ 614.209033] #2: ffff0008784e0110 (sk_lock-AF_INET-RPC){....}, at: tcp_sendmsg+0x24/0x58 [ 614.235429] CPU: 0 PID: 40 Comm: kworker/u4:4 Not tainted 5.6.0-rc3-00926-g4a165a9d5921 #26 [ 614.260854] Hardware name: ARM Test FPGA (DT) [ 614.274734] Workqueue: rpciod rpc_async_schedule [ 614.289022] Call trace: [ 614.296871] dump_backtrace+0x0/0x1a0 [ 614.308311] show_stack+0x14/0x20 [ 614.318751] dump_stack+0xbc/0x100 [ 614.329403] ___might_sleep+0xf0/0x140 [ 614.341018] __might_sleep+0x4c/0x80 [ 614.352201] __mutex_lock+0x5c/0x8a8 [ 614.363348] mutex_lock_nested+0x1c/0x28 [ 614.375654] axienet_dma_err_handler+0x38/0x388 [ 614.389999] tasklet_action_common.isra.15+0x160/0x1a8 [ 614.405894] tasklet_action+0x24/0x30 [ 614.417297] efi_header_end+0xe0/0x494 [ 614.429020] irq_exit+0xd0/0xd8 [ 614.439047] __handle_domain_irq+0x60/0xb0 [ 614.451877] gic_handle_irq+0xdc/0x2d0 [ 614.463486] el1_irq+0xcc/0x180 [ 614.473451] __tcp_transmit_skb+0x41c/0xb58 [ 614.486513] tcp_write_xmit+0x224/0x10a0 [ 614.498792] __tcp_push_pending_frames+0x38/0xc8 [ 614.513126] tcp_rcv_established+0x41c/0x820 [ 614.526301] tcp_v4_do_rcv+0x8c/0x218 [ 614.537784] __release_sock+0x5c/0x108 [ 614.549466] release_sock+0x34/0xa0 [ 614.560318] tcp_sendmsg+0x40/0x58 [ 614.571053] inet_sendmsg+0x40/0x68 [ 614.582061] sock_sendmsg+0x18/0x30 [ 614.593074] xs_sendpages+0x218/0x328 [ 614.604506] xs_tcp_send_request+0xa0/0x1b8 [ 614.617461] xprt_transmit+0xc8/0x4f0 [ 614.628943] call_transmit+0x8c/0xa0 [ 614.640028] __rpc_execute+0xbc/0x6f8 [ 614.651380] rpc_async_schedule+0x28/0x48 [ 614.663846] process_one_work+0x298/0x6a8 [ 614.676299] worker_thread+0x40/0x490 [ 614.687687] kthread+0x134/0x138 [ 614.697804] ret_from_fork+0x10/0x18 [ 614.717319] xilinx_axienet 7fe00000.ethernet eth0: Link is Down [ 615.748343] xilinx_axienet 7fe00000.ethernet eth0: Link is Up - 1Gbps/Full - flow control off Since tasklets are not really popular anymore anyway, lets convert this over to a work queue, which can sleep and thus can take the MDIO mutex. Signed-off-by: Andre Przywara --- drivers/net/ethernet/xilinx/xilinx_axienet.h | 2 +- .../net/ethernet/xilinx/xilinx_axienet_main.c | 24 +++++++++---------- 2 files changed, 13 insertions(+), 13 deletions(-) diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet.h b/drivers/net/ethernet/xilinx/xilinx_axienet.h index 2dacfc85b3ba..04e51af32178 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet.h +++ b/drivers/net/ethernet/xilinx/xilinx_axienet.h @@ -435,7 +435,7 @@ struct axienet_local { void __iomem *regs; void __iomem *dma_regs; - struct tasklet_struct dma_err_tasklet; + struct work_struct dma_err_task; int tx_irq; int rx_irq; diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c index e2f3e2b0cec7..d4c872425065 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c @@ -806,7 +806,7 @@ static irqreturn_t axienet_tx_irq(int irq, void *_ndev) /* Write to the Rx channel control register */ axienet_dma_out32(lp, XAXIDMA_RX_CR_OFFSET, cr); - tasklet_schedule(&lp->dma_err_tasklet); + schedule_work(&lp->dma_err_task); axienet_dma_out32(lp, XAXIDMA_TX_SR_OFFSET, status); } out: @@ -855,7 +855,7 @@ static irqreturn_t axienet_rx_irq(int irq, void *_ndev) /* write to the Rx channel control register */ axienet_dma_out32(lp, XAXIDMA_RX_CR_OFFSET, cr); - tasklet_schedule(&lp->dma_err_tasklet); + schedule_work(&lp->dma_err_task); axienet_dma_out32(lp, XAXIDMA_RX_SR_OFFSET, status); } out: @@ -891,7 +891,7 @@ static irqreturn_t axienet_eth_irq(int irq, void *_ndev) return IRQ_HANDLED; } -static void axienet_dma_err_handler(unsigned long data); +static void axienet_dma_err_handler(struct work_struct *work); /** * axienet_open - Driver open routine. @@ -935,9 +935,8 @@ static int axienet_open(struct net_device *ndev) phylink_start(lp->phylink); - /* Enable tasklets for Axi DMA error handling */ - tasklet_init(&lp->dma_err_tasklet, axienet_dma_err_handler, - (unsigned long) lp); + /* Enable worker thread for Axi DMA error handling */ + INIT_WORK(&lp->dma_err_task, axienet_dma_err_handler); /* Enable interrupts for Axi DMA Tx */ ret = request_irq(lp->tx_irq, axienet_tx_irq, IRQF_SHARED, @@ -966,7 +965,7 @@ static int axienet_open(struct net_device *ndev) err_tx_irq: phylink_stop(lp->phylink); phylink_disconnect_phy(lp->phylink); - tasklet_kill(&lp->dma_err_tasklet); + cancel_work_sync(&lp->dma_err_task); dev_err(lp->dev, "request_irq() failed\n"); return ret; } @@ -1025,7 +1024,7 @@ static int axienet_stop(struct net_device *ndev) axienet_mdio_enable(lp); mutex_unlock(&lp->mii_bus->mdio_lock); - tasklet_kill(&lp->dma_err_tasklet); + cancel_work_sync(&lp->dma_err_task); if (lp->eth_irq > 0) free_irq(lp->eth_irq, ndev); @@ -1484,17 +1483,18 @@ static const struct phylink_mac_ops axienet_phylink_ops = { }; /** - * axienet_dma_err_handler - Tasklet handler for Axi DMA Error - * @data: Data passed + * axienet_dma_err_handler - Work queue task for Axi DMA Error + * @work: pointer to work_struct * * Resets the Axi DMA and Axi Ethernet devices, and reconfigures the * Tx/Rx BDs. */ -static void axienet_dma_err_handler(unsigned long data) +static void axienet_dma_err_handler(struct work_struct *work) { u32 axienet_status; u32 cr, i; - struct axienet_local *lp = (struct axienet_local *) data; + struct axienet_local *lp = container_of(work, struct axienet_local, + dma_err_task); struct net_device *ndev = lp->ndev; struct axidma_bd *cur_p;