From patchwork Thu Oct 6 13:49:23 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Manivannan Sadhasivam X-Patchwork-Id: 13000380 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 56DA2C433FE for ; Thu, 6 Oct 2022 13:49:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230267AbiJFNtx (ORCPT ); Thu, 6 Oct 2022 09:49:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48048 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231332AbiJFNtt (ORCPT ); Thu, 6 Oct 2022 09:49:49 -0400 Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B7CA3B1FD for ; Thu, 6 Oct 2022 06:49:46 -0700 (PDT) Received: by mail-pj1-x102d.google.com with SMTP id i7-20020a17090a65c700b0020ad9666a86so4426578pjs.0 for ; Thu, 06 Oct 2022 06:49:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date; bh=pAOyHNo2Ogz8benvCK0BMK/ZXWCdH9NtvY9tUBlmQgQ=; b=oTowoydDyAkpARgML6g7GzRmeF311CW8HrohiULAiRheYMxj6z6voHc8PfiRDQLJZk SeZw8sGXTS3+F0uR90r3XWrTaDY+dMkWEyHdsEzIWq0bDGc+Yhy18zyRhJLUrTfv0mJ6 wyjZegco+9RmBprKj1PbsUoZN0s6CuT76Y9ONE9W/0IZzsP11OcW8DazvxDUTIteCNg7 gS8ZYO8ClzaVr4ppD82Ji05lS2BlZ6IqNH5y520tFmU3NMXffLvKS4t/47riODMHPhb/ ephjK7oyDc5COw37/or/6RQhjg5/yuN1Ga03gPyTPPStucja6tvOt6HRcywSaaArQrIu +qDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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; bh=pAOyHNo2Ogz8benvCK0BMK/ZXWCdH9NtvY9tUBlmQgQ=; b=x/dLci3KbPkaugfE5cRInTzJG9WZqWYHG+R6B163jZHunVoTOfyn+qTBHepjEgMN3e vzI9xBXQ3J22RelgtUjhhoDhBd14dXtMUAXX1XAxvg8ax/4rw9AP5BlDoZ50KphK8b1o GKkD76Mf8Ids7qdXQnvstOxE7ltNJe702+qVlyHJDJsvYRt2yMwocfGmZzh7sfpcYwmt aw3jWbLgEoopBauTmuOtjupF26cvqoyra/KMYCwj4CvJAxCUcbgjWHtwNS4WmEHD09ey z/ZyCgsSdWPJvEGcpDGjYHPLpdJzp63OJtGSjgLDUbFtZcJoZ5nW5vl3LvV0iosWkvEe mGkg== X-Gm-Message-State: ACrzQf0aNlFooO4FFztha7G7mrPXAC5Dl3Ox0jx6/YkzTYMuEpe0aXV7 ajli4eiw5mMVoN0D+NKCJA9m X-Google-Smtp-Source: AMsMyM5cCrhHsinO11H0aWRdW1l/kf7wzsq5ZSXzHZMnGUbODs1FP0WILk8VIRrN2z+giOjEXAHBxw== X-Received: by 2002:a17:90b:1d85:b0:20b:20b0:29cd with SMTP id pf5-20020a17090b1d8500b0020b20b029cdmr580300pjb.131.1665064185925; Thu, 06 Oct 2022 06:49:45 -0700 (PDT) Received: from localhost.localdomain ([220.158.158.220]) by smtp.gmail.com with ESMTPSA id k25-20020a635a59000000b00434760ee36asm1874053pgm.16.2022.10.06.06.49.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 06 Oct 2022 06:49:44 -0700 (PDT) From: Manivannan Sadhasivam To: kishon@kernel.org, lpieralisi@kernel.org, bhelgaas@google.com Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, kw@linux.com, robh@kernel.org, vidyas@nvidia.com, vigneshr@ti.com, Manivannan Sadhasivam Subject: [PATCH v3 1/5] PCI: dra7xx: Use threaded IRQ handler for "dra7xx-pcie-main" IRQ Date: Thu, 6 Oct 2022 19:19:23 +0530 Message-Id: <20221006134927.41437-2-manivannan.sadhasivam@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221006134927.41437-1-manivannan.sadhasivam@linaro.org> References: <20221006134927.41437-1-manivannan.sadhasivam@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The "dra7xx-pcie-main" hard IRQ handler is just printing the IRQ status and calling the dw_pcie_ep_linkup() API if LINK_UP status is set. But the execution of dw_pcie_ep_linkup() depends on the EPF driver and may take more time depending on the EPF implementation. In general, hard IRQ handlers are supposed to return quickly and not block for so long. Moreover, there is no real need of the current IRQ handler to be a hard IRQ handler. So switch to the threaded IRQ handler for the "dra7xx-pcie-main" IRQ. Signed-off-by: Manivannan Sadhasivam Acked-by: Kishon Vijay Abraham I --- drivers/pci/controller/dwc/pci-dra7xx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c index 38462ed11d07..4ae807e7cf79 100644 --- a/drivers/pci/controller/dwc/pci-dra7xx.c +++ b/drivers/pci/controller/dwc/pci-dra7xx.c @@ -840,7 +840,7 @@ static int dra7xx_pcie_probe(struct platform_device *pdev) } dra7xx->mode = mode; - ret = devm_request_irq(dev, irq, dra7xx_pcie_irq_handler, + ret = devm_request_threaded_irq(dev, irq, NULL, dra7xx_pcie_irq_handler, IRQF_SHARED, "dra7xx-pcie-main", dra7xx); if (ret) { dev_err(dev, "failed to request irq\n"); From patchwork Thu Oct 6 13:49:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Manivannan Sadhasivam X-Patchwork-Id: 13000381 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EB6BBC433F5 for ; Thu, 6 Oct 2022 13:50:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231691AbiJFNuL (ORCPT ); Thu, 6 Oct 2022 09:50:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50184 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231608AbiJFNuH (ORCPT ); Thu, 6 Oct 2022 09:50:07 -0400 Received: from mail-pl1-x632.google.com (mail-pl1-x632.google.com [IPv6:2607:f8b0:4864:20::632]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87FCF10FC9 for ; Thu, 6 Oct 2022 06:49:53 -0700 (PDT) Received: by mail-pl1-x632.google.com with SMTP id z20so1751283plb.10 for ; Thu, 06 Oct 2022 06:49:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date; bh=PFAW0jcwtPS3OhOTEsyS1TaHRevCT8P/51hfS6qzO/0=; b=XbL5jZNUUKXEiK1u2yAh2XjMo9JrXVhEG6s45pdssMhcckLQfzKl5TyNqp9xhLguG9 ov6efDxeJ/OpTauHbeWKGubyk8nmkZ0frvB0931/42GCU57aK6jZmmRo3EFq0Wvrk/sQ VveP+1s1nqV3fnYAbx7ypCAZ6ZuRFEh6L0VeoWsPg6P8u34Q5ByaRzYQNEV3kp8I7n2u SHIQ/piSpxgfOgTtTfDazd5KPaVJ6aGCsIamTS1HLctAbMOyWeXIHxSQVEH7KzUbCvqA 7pF/b/C78Bfq9nQctz1ynXZDPLyzvd54oOeF/pJMBz2+1jgUkgwUUliCH6+OvmItDzjG f5Pw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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; bh=PFAW0jcwtPS3OhOTEsyS1TaHRevCT8P/51hfS6qzO/0=; b=cffdyET95qPvHZCDcSHi2SzxhYChn4g98o/2G5Jwhw134pQ8ksrEr+VIhQeeXbMtL0 BeCONUihKuV6AUwUkaNw/y3e+2+YrwRiS9FJWteFgr7Opy7NhC/0ApQyvnNjlPSqZw6i ZJ4w7ofhApcumnSVvE46zydK36pfgFWTJofW/K/5GAYkYirgsXQQgULKROhzv6AF0QlD 9owF1lYQnVQgpbRSJXNzEUtnUbeIoX7OGfHcPLYLmg7TnlYa4YkkrhbaVszFeo1EuVaC PK1zfkLa3Cm0KNSO/4Y7H10yYiIYmF9E/xjbd0nFDAj+7PaI6F1tVFSXTMmNHnEwxWGE lRxA== X-Gm-Message-State: ACrzQf0vhpcfgr9lcc4y/e8IbE0Z0u/Vc45KB1mt7/dv5HZDJG99HdOK 0deQNoUtrNp00ndCkfoai3sp X-Google-Smtp-Source: AMsMyM5xaxKXrosoPmAx2Qu5DUI+EN+99LbrZR2mjLKSwZpFm2w1XpzWVVo9XnEfhsv6NC31xPKYOg== X-Received: by 2002:a17:903:2d1:b0:17d:ba07:42d4 with SMTP id s17-20020a17090302d100b0017dba0742d4mr4859423plk.92.1665064191962; Thu, 06 Oct 2022 06:49:51 -0700 (PDT) Received: from localhost.localdomain ([220.158.158.220]) by smtp.gmail.com with ESMTPSA id k25-20020a635a59000000b00434760ee36asm1874053pgm.16.2022.10.06.06.49.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 06 Oct 2022 06:49:49 -0700 (PDT) From: Manivannan Sadhasivam To: kishon@kernel.org, lpieralisi@kernel.org, bhelgaas@google.com Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, kw@linux.com, robh@kernel.org, vidyas@nvidia.com, vigneshr@ti.com, Manivannan Sadhasivam Subject: [PATCH v3 2/5] PCI: tegra194: Move dw_pcie_ep_linkup() to threaded IRQ handler Date: Thu, 6 Oct 2022 19:19:24 +0530 Message-Id: <20221006134927.41437-3-manivannan.sadhasivam@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221006134927.41437-1-manivannan.sadhasivam@linaro.org> References: <20221006134927.41437-1-manivannan.sadhasivam@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org dw_pcie_ep_linkup() may take more time to execute depending on the EPF driver implementation. Calling this API in the hard IRQ handler is not encouraged since the hard IRQ handlers are supposed to complete quickly. So move the dw_pcie_ep_linkup() call to threaded IRQ handler. Signed-off-by: Manivannan Sadhasivam --- drivers/pci/controller/dwc/pcie-tegra194.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c index 1b6b437823d2..6a487f52e1fb 100644 --- a/drivers/pci/controller/dwc/pcie-tegra194.c +++ b/drivers/pci/controller/dwc/pcie-tegra194.c @@ -287,6 +287,7 @@ struct tegra_pcie_dw { struct gpio_desc *pex_refclk_sel_gpiod; unsigned int pex_rst_irq; int ep_state; + long link_status; }; static inline struct tegra_pcie_dw *to_tegra_pcie(struct dw_pcie *pci) @@ -450,9 +451,13 @@ static void pex_ep_event_hot_rst_done(struct tegra_pcie_dw *pcie) static irqreturn_t tegra_pcie_ep_irq_thread(int irq, void *arg) { struct tegra_pcie_dw *pcie = arg; + struct dw_pcie_ep *ep = &pcie->pci.ep; struct dw_pcie *pci = &pcie->pci; u32 val, speed; + if (test_and_clear_bit(0, &pcie->link_status)) + dw_pcie_ep_linkup(ep); + speed = dw_pcie_readw_dbi(pci, pcie->pcie_cap_base + PCI_EXP_LNKSTA) & PCI_EXP_LNKSTA_CLS; clk_set_rate(pcie->core_clk, pcie_gen_freq[speed - 1]); @@ -499,7 +504,6 @@ static irqreturn_t tegra_pcie_ep_irq_thread(int irq, void *arg) static irqreturn_t tegra_pcie_ep_hard_irq(int irq, void *arg) { struct tegra_pcie_dw *pcie = arg; - struct dw_pcie_ep *ep = &pcie->pci.ep; int spurious = 1; u32 status_l0, status_l1, link_status; @@ -515,7 +519,7 @@ static irqreturn_t tegra_pcie_ep_hard_irq(int irq, void *arg) link_status = appl_readl(pcie, APPL_LINK_STATUS); if (link_status & APPL_LINK_STATUS_RDLH_LINK_UP) { dev_dbg(pcie->dev, "Link is up with Host\n"); - dw_pcie_ep_linkup(ep); + set_bit(0, &pcie->link_status); } } From patchwork Thu Oct 6 13:49:25 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Manivannan Sadhasivam X-Patchwork-Id: 13000382 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5458AC4332F for ; Thu, 6 Oct 2022 13:50:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231631AbiJFNuP (ORCPT ); Thu, 6 Oct 2022 09:50:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50156 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231676AbiJFNuJ (ORCPT ); Thu, 6 Oct 2022 09:50:09 -0400 Received: from mail-pj1-x1033.google.com (mail-pj1-x1033.google.com [IPv6:2607:f8b0:4864:20::1033]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B7ECC28E27 for ; Thu, 6 Oct 2022 06:49:57 -0700 (PDT) Received: by mail-pj1-x1033.google.com with SMTP id fw14so1799086pjb.3 for ; Thu, 06 Oct 2022 06:49:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date; bh=mWMJic3+3eVweR7Hb3wJwKAsDypmbh3PTgAfppiGim0=; b=ZkJ3eSSvWEQHG4zrCYO/rtAQMC+rTCblUgkXT/sojUfeAz6djcfzmaQhTE1VFhHlb5 c1atXYEjU3xEGE7hI13KaDEcIgKWkEtN1hvwHwEilxv96++sncyPLWqzhVGEXpdUs06G CdnNu3apyqKTZeVSCSOWHTmHzGnFe3F2KnJM3MWKtya9Y3YnYefumWTirYL9USS1lYub A/mEPLmhBfwN3a8nKOKM2rGPY5Mu7KrZF82KX4Ex4dyspcvVZE3FoiZPzuE8M8MOv+bw OGNw6BEO2hAZNd93A/lo5mHGoPx0ZTYnxKuuVNn8KZcYJUWz6h7H+Lqu3yOpWNU2Gh62 93nA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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; bh=mWMJic3+3eVweR7Hb3wJwKAsDypmbh3PTgAfppiGim0=; b=qh4qFs/4LQKzku6PoSLoLFTdga8SuFGUHRQm5Sfs2Z8uqFdZvxdOogAqYxO4e0TL3y QD1GIpHc6mjcjTYgKXXueLq/203PaCgnfUmNoi1eyWg4dvf1zcUzRodXUiCVzQWvgBDI Fvt8+Q1SJ3Aj1vK5tI8DPaZB4ZhiglPRPxmDpdGMx1Sb1HWedvMP6MPcOZWFl8cb2Qpz M+/wGPS+3P8HwUteXJFR1Gw2R4eYiuE90bNoKLxfbWADoGISmL54YuWB18Ddau1SFM8u TIBTHaDN3ji+X7BRJFBEsFXUvIdXg66CQF51tckngW29dVk2wMrLJhZ2pTKqfNikp4dN VLUQ== X-Gm-Message-State: ACrzQf0hfQPMHkI6uYxuZa45GHenUoAR9Xc/C1vo7dI4iI9sf2ymk2qM Mh0llHCMHmkx6FPncdyp7DXL X-Google-Smtp-Source: AMsMyM6adD7Qiz1npAI/QIQqcXzzqSFAqQ7y/8Uf2egzhAubDRgCFWLfQ2y5Xniqseks4ePMXNdkGg== X-Received: by 2002:a17:90a:4b47:b0:20a:e47c:1450 with SMTP id o7-20020a17090a4b4700b0020ae47c1450mr10742123pjl.198.1665064195847; Thu, 06 Oct 2022 06:49:55 -0700 (PDT) Received: from localhost.localdomain ([220.158.158.220]) by smtp.gmail.com with ESMTPSA id k25-20020a635a59000000b00434760ee36asm1874053pgm.16.2022.10.06.06.49.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 06 Oct 2022 06:49:55 -0700 (PDT) From: Manivannan Sadhasivam To: kishon@kernel.org, lpieralisi@kernel.org, bhelgaas@google.com Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, kw@linux.com, robh@kernel.org, vidyas@nvidia.com, vigneshr@ti.com, Manivannan Sadhasivam Subject: [PATCH v3 3/5] PCI: endpoint: Use a separate lock for protecting epc->pci_epf list Date: Thu, 6 Oct 2022 19:19:25 +0530 Message-Id: <20221006134927.41437-4-manivannan.sadhasivam@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221006134927.41437-1-manivannan.sadhasivam@linaro.org> References: <20221006134927.41437-1-manivannan.sadhasivam@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The EPC controller maintains a list of EPF drivers added to it. For protecting this list against the concurrent accesses, the epc->lock (used for protecting epc_ops) has been used so far. Since there were no users trying to use epc_ops and modify the pci_epf list simultaneously, this was not an issue. But with the addition of callback mechanism for passing the events, this will be a problem. Because the pci_epf list needs to be iterated first for getting hold of the EPF driver and then the relevant event specific callback needs to be called for the driver. If the same epc->lock is used, then it will result in a deadlock scenario. For instance, ... mutex_lock(&epc->lock); list_for_each_entry(epf, &epc->pci_epf, list) { epf->event_ops->core_init(epf); | |-> pci_epc_set_bar(); | |-> mutex_lock(&epc->lock) # DEADLOCK ... So to fix this issue, use a separate lock called "list_lock" for protecting the pci_epf list against the concurrent accesses. This lock will also be used by the callback mechanism. Signed-off-by: Manivannan Sadhasivam Acked-by: Kishon Vijay Abraham I --- drivers/pci/endpoint/pci-epc-core.c | 9 +++++---- include/linux/pci-epc.h | 2 ++ 2 files changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index 3bc9273d0a08..6cce430d431b 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -613,7 +613,7 @@ int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf, if (type == SECONDARY_INTERFACE && epf->sec_epc) return -EBUSY; - mutex_lock(&epc->lock); + mutex_lock(&epc->list_lock); func_no = find_first_zero_bit(&epc->function_num_map, BITS_PER_LONG); if (func_no >= BITS_PER_LONG) { @@ -640,7 +640,7 @@ int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf, list_add_tail(list, &epc->pci_epf); ret: - mutex_unlock(&epc->lock); + mutex_unlock(&epc->list_lock); return ret; } @@ -672,11 +672,11 @@ void pci_epc_remove_epf(struct pci_epc *epc, struct pci_epf *epf, list = &epf->sec_epc_list; } - mutex_lock(&epc->lock); + mutex_lock(&epc->list_lock); clear_bit(func_no, &epc->function_num_map); list_del(list); epf->epc = NULL; - mutex_unlock(&epc->lock); + mutex_unlock(&epc->list_lock); } EXPORT_SYMBOL_GPL(pci_epc_remove_epf); @@ -773,6 +773,7 @@ __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, } mutex_init(&epc->lock); + mutex_init(&epc->list_lock); INIT_LIST_HEAD(&epc->pci_epf); ATOMIC_INIT_NOTIFIER_HEAD(&epc->notifier); diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index a48778e1a4ee..fe729dfe509b 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -122,6 +122,7 @@ struct pci_epc_mem { * struct pci_epc - represents the PCI EPC device * @dev: PCI EPC device * @pci_epf: list of endpoint functions present in this EPC device + * list_lock: Mutex for protecting pci_epf list * @ops: function pointers for performing endpoint operations * @windows: array of address space of the endpoint controller * @mem: first window of the endpoint controller, which corresponds to @@ -139,6 +140,7 @@ struct pci_epc_mem { struct pci_epc { struct device dev; struct list_head pci_epf; + struct mutex list_lock; const struct pci_epc_ops *ops; struct pci_epc_mem **windows; struct pci_epc_mem *mem; From patchwork Thu Oct 6 13:49:26 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Manivannan Sadhasivam X-Patchwork-Id: 13000383 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 59C08C433FE for ; Thu, 6 Oct 2022 13:50:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231576AbiJFNuR (ORCPT ); Thu, 6 Oct 2022 09:50:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231634AbiJFNuM (ORCPT ); Thu, 6 Oct 2022 09:50:12 -0400 Received: from mail-pl1-x629.google.com (mail-pl1-x629.google.com [IPv6:2607:f8b0:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8749C45F49 for ; Thu, 6 Oct 2022 06:50:00 -0700 (PDT) Received: by mail-pl1-x629.google.com with SMTP id l4so1760231plb.8 for ; Thu, 06 Oct 2022 06:50:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date; bh=b98/tdiTwcvqr19Hh3b2b2FTs+schd1Q4q9W1vv+i7w=; b=f3lE3n1jFX5eANT3457wStFC3x8NgEWMerXa7SYsS4AMyPnchWeOmot0g5vwPiv7L4 fW/GZheMjMzyAB2CJjKXehrMRRdBFEpBpHdgWpWcfK9aKcLCTrXWFA3vCvShmnv1mLwD MjPE5DlX+qXwxPMjeOe4iEw6zecAQlA9csayKh8ddVPAXmVrKyCNxqPPP+h21TRSJQj1 OBWFt3BUrldpwTkbV8S87/iPicmgvPcnhCU7V+nWUFLHxfiA0obg2DyU9c3Y/uSONYRT j5HwA0BPZ7qYXgdzqdZW9NFCvTD+W0cWNuSQ+bfCFM/Vv59+yluuLCJTjtZafKpqTx4L iFFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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; bh=b98/tdiTwcvqr19Hh3b2b2FTs+schd1Q4q9W1vv+i7w=; b=VQVfcr4J6rSZ0RZuHLPOQmnnOj8RC3YfAsLJjYfbnV5WflTwzDh+44/ngHZaKMZhGP 76yjtnckBIuP1siUDGJn+QFScvFjdCE++L9cB9GLrl97ib/fG3k5sQOjIPrn/lFhdDPi vET6XCd6pHUlYBYr6t8S7ZE1Vs4Z/QgnlzeT9wMzEYpWtGP7Yqxq6F46UqPZsk0Hz+dL lzAd24t6r0uWZVRupGyNPbmZpuNALETHlwI/+p5p7lkwueO84bHCKKeUlLqxwaHAGf5m hulcv7w4A7MzClY4pM7CtcqQtTyT56B5vFaNRjnVZD9T+shiPERYaaJ1KxueGDbp+WJd 1K/g== X-Gm-Message-State: ACrzQf3eaV3MlxD9+rzrDFvwc7ocTkE5gxMGyyf+4yJ3A/qNOUkunN9x qM6nhyW8BBbNfmEeiU33QTO9 X-Google-Smtp-Source: AMsMyM4P7ZuRzbrkXhZRWHNPuzPp2qehAKeCoVS8zM5dgefeOtWm2noYpuK7VzCYrXRQHqTic/7a8Q== X-Received: by 2002:a17:90a:cd02:b0:205:efbd:6f60 with SMTP id d2-20020a17090acd0200b00205efbd6f60mr10800376pju.111.1665064199534; Thu, 06 Oct 2022 06:49:59 -0700 (PDT) Received: from localhost.localdomain ([220.158.158.220]) by smtp.gmail.com with ESMTPSA id k25-20020a635a59000000b00434760ee36asm1874053pgm.16.2022.10.06.06.49.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 06 Oct 2022 06:49:58 -0700 (PDT) From: Manivannan Sadhasivam To: kishon@kernel.org, lpieralisi@kernel.org, bhelgaas@google.com Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, kw@linux.com, robh@kernel.org, vidyas@nvidia.com, vigneshr@ti.com, Manivannan Sadhasivam Subject: [PATCH v3 4/5] PCI: endpoint: Use callback mechanism for passing events from EPC to EPF Date: Thu, 6 Oct 2022 19:19:26 +0530 Message-Id: <20221006134927.41437-5-manivannan.sadhasivam@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221006134927.41437-1-manivannan.sadhasivam@linaro.org> References: <20221006134927.41437-1-manivannan.sadhasivam@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Instead of using the notifiers for passing the events from EPC to EPF, let's introduce a callback based mechanism where the EPF drivers can populate relevant callbacks for EPC events they want to subscribe. The use of notifiers in kernel is not recommended if there is a real link between the sender and receiver, like in this case. Also, the existing atomic notifier forces the notification functions to be in atomic context while the caller may be in non-atomic context. For instance, the two in-kernel users of the notifiers, pcie-qcom and pcie-tegra194, both are calling the notifier functions in non-atomic context (from threaded IRQ handlers). This creates a sleeping in atomic context issue with the existing EPF_TEST driver that calls the EPC APIs that may sleep. For all these reasons, let's get rid of the notifier chains and use the simple callback mechanism for signalling the events from EPC to EPF drivers. This preserves the context of the caller and avoids the latency of going through a separate interface for triggering the notifications. As a first step of the transition, the core_init() callback is introduced in this commit, that'll replace the existing CORE_INIT notifier used for signalling the init complete event from EPC. During the occurrence of the event, EPC will go over the list of EPF drivers attached to it and will call the core_init() callback if available. Signed-off-by: Manivannan Sadhasivam --- drivers/pci/endpoint/functions/pci-epf-test.c | 13 ++++++------- drivers/pci/endpoint/pci-epc-core.c | 11 ++++++++++- include/linux/pci-epf.h | 11 ++++++++++- 3 files changed, 26 insertions(+), 9 deletions(-) diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c index a6f906a96669..868de17e1ad2 100644 --- a/drivers/pci/endpoint/functions/pci-epf-test.c +++ b/drivers/pci/endpoint/functions/pci-epf-test.c @@ -826,20 +826,17 @@ static int pci_epf_test_core_init(struct pci_epf *epf) return 0; } +static const struct pci_epc_event_ops pci_epf_test_event_ops = { + .core_init = pci_epf_test_core_init, +}; + static int pci_epf_test_notifier(struct notifier_block *nb, unsigned long val, void *data) { struct pci_epf *epf = container_of(nb, struct pci_epf, nb); struct pci_epf_test *epf_test = epf_get_drvdata(epf); - int ret; switch (val) { - case CORE_INIT: - ret = pci_epf_test_core_init(epf); - if (ret) - return NOTIFY_BAD; - break; - case LINK_UP: queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler, msecs_to_jiffies(1)); @@ -1010,6 +1007,8 @@ static int pci_epf_test_probe(struct pci_epf *epf, const struct pci_epf_device_i INIT_DELAYED_WORK(&epf_test->cmd_handler, pci_epf_test_cmd_handler); + epf->event_ops = &pci_epf_test_event_ops; + epf_set_drvdata(epf, epf_test); return 0; } diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index 6cce430d431b..ba54f17ae06f 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -707,10 +707,19 @@ EXPORT_SYMBOL_GPL(pci_epc_linkup); */ void pci_epc_init_notify(struct pci_epc *epc) { + struct pci_epf *epf; + if (!epc || IS_ERR(epc)) return; - atomic_notifier_call_chain(&epc->notifier, CORE_INIT, NULL); + mutex_lock(&epc->list_lock); + list_for_each_entry(epf, &epc->pci_epf, list) { + mutex_lock(&epf->lock); + if (epf->event_ops->core_init) + epf->event_ops->core_init(epf); + mutex_unlock(&epf->lock); + } + mutex_unlock(&epc->list_lock); } EXPORT_SYMBOL_GPL(pci_epc_init_notify); diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h index 0c94cc1513bc..a06f3b4c8bee 100644 --- a/include/linux/pci-epf.h +++ b/include/linux/pci-epf.h @@ -18,7 +18,6 @@ struct pci_epf; enum pci_epc_interface_type; enum pci_notify_event { - CORE_INIT, LINK_UP, }; @@ -72,6 +71,14 @@ struct pci_epf_ops { struct config_group *group); }; +/** + * struct pci_epf_event_ops - Callbacks for capturing the EPC events + * @core_init: Callback for the EPC initialization complete event + */ +struct pci_epc_event_ops { + int (*core_init)(struct pci_epf *epf); +}; + /** * struct pci_epf_driver - represents the PCI EPF driver * @probe: ops to perform when a new EPF device has been bound to the EPF driver @@ -140,6 +147,7 @@ struct pci_epf_bar { * @is_vf: true - virtual function, false - physical function * @vfunction_num_map: bitmap to manage virtual function number * @pci_vepf: list of virtual endpoint functions associated with this function + * @event_ops: Callbacks for capturing the EPC events */ struct pci_epf { struct device dev; @@ -170,6 +178,7 @@ struct pci_epf { unsigned int is_vf; unsigned long vfunction_num_map; struct list_head pci_vepf; + const struct pci_epc_event_ops *event_ops; }; /** From patchwork Thu Oct 6 13:49:27 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Manivannan Sadhasivam X-Patchwork-Id: 13000384 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 43FF4C433FE for ; Thu, 6 Oct 2022 13:50:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231700AbiJFNuh (ORCPT ); Thu, 6 Oct 2022 09:50:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51808 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231707AbiJFNuV (ORCPT ); Thu, 6 Oct 2022 09:50:21 -0400 Received: from mail-pf1-x432.google.com (mail-pf1-x432.google.com [IPv6:2607:f8b0:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 531377F247 for ; Thu, 6 Oct 2022 06:50:04 -0700 (PDT) Received: by mail-pf1-x432.google.com with SMTP id y8so2062896pfp.13 for ; Thu, 06 Oct 2022 06:50:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date; bh=Y0MJ+CUZZvqiC06rOGoANeiEeLDH+rfWRVr8HGOI0zE=; b=m+gzwteEDOkMfL/WFoicBOTuBgNGNC5upbaRmlPnAq2+eHEimZ0IGhaNNfATO+I1td Fn3w+pSkPbAUQQa+rkRijGa3SOLJqJYtHJTyXKs4hyB72V3W7V/U2Ju2JTuaz3TPRuy8 B/lfYiInVeMGS/AEKNlIqfgp3kvP4FqNs6b4T5RIYUSZEwPbWY23T9iBKt9q1M12iay+ nfyyiG3eZdJgU1qkdUtEveHSxNp3sEcXFQi/6ptvJGqyVM2PmZpcQ9QSw6PPFtIX/AUV wtSMKYDrziZaMG9NJ2K/LQ0SJ7TTIdKtukh7jaIuLOjvubG3sGCpuwKnzJP74uvJKdKO aobQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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; bh=Y0MJ+CUZZvqiC06rOGoANeiEeLDH+rfWRVr8HGOI0zE=; b=F09b/uNETVlFRoXpXJJhPzmWxpExI1bhuNXg3zNmEZqmF0ZClWVXyloefl/ACzsxvv 8hlC5Shog4bSfVaipgsvcbWnGURXLa8qaAeFnlMp2OYc+CmWydqxIn3LNuGB62aJ0Z+M SgylgE24FBhxh899MHI4lIojft70CQvRdy8//ilV69UeNRmHWubUeoSvwYhUbu0Dtn1I 7pvN6KvTjbyMIvPsSEaxdL1fbOIpQNOhtPQYznTNRVO4HpfLIwZ7aqnmZjwLMe7TZwqk GuxK5oGj2tjelRZNEbXfSl6H6cZvYKIDraDEBLrRFjsVxoplYpc0B4rweABFcwfx69u/ wA1w== X-Gm-Message-State: ACrzQf2VA+RAoH5u+IuDcxgFjJVOajbpM15g5xU0qA8kXmt0eH4fynuC rwmS0mSa2Sfa4CgyLxiVP23P X-Google-Smtp-Source: AMsMyM7gSbJZ96bcqtZTdVs4/z84De0pFcLRe4b2AbJgXTAHQk0JwrMBVcmscWQYl5xaVRo5E2YdJQ== X-Received: by 2002:a63:b545:0:b0:43c:2ad9:b00 with SMTP id u5-20020a63b545000000b0043c2ad90b00mr1456pgo.535.1665064203337; Thu, 06 Oct 2022 06:50:03 -0700 (PDT) Received: from localhost.localdomain ([220.158.158.220]) by smtp.gmail.com with ESMTPSA id k25-20020a635a59000000b00434760ee36asm1874053pgm.16.2022.10.06.06.49.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 06 Oct 2022 06:50:02 -0700 (PDT) From: Manivannan Sadhasivam To: kishon@kernel.org, lpieralisi@kernel.org, bhelgaas@google.com Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, kw@linux.com, robh@kernel.org, vidyas@nvidia.com, vigneshr@ti.com, Manivannan Sadhasivam Subject: [PATCH v3 5/5] PCI: endpoint: Use link_up() callback in place of LINK_UP notifier Date: Thu, 6 Oct 2022 19:19:27 +0530 Message-Id: <20221006134927.41437-6-manivannan.sadhasivam@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221006134927.41437-1-manivannan.sadhasivam@linaro.org> References: <20221006134927.41437-1-manivannan.sadhasivam@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org As a part of the transition towards callback mechanism for signalling the events from EPC to EPF, let's use the link_up() callback in the place of the LINK_UP notifier. This also removes the notifier support completely from the PCI endpoint framework. Signed-off-by: Manivannan Sadhasivam --- drivers/pci/endpoint/functions/pci-epf-test.c | 33 ++++++------------- drivers/pci/endpoint/pci-epc-core.c | 12 +++++-- include/linux/pci-epc.h | 8 ----- include/linux/pci-epf.h | 8 ++--- 4 files changed, 22 insertions(+), 39 deletions(-) diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c index 868de17e1ad2..f75045f2dee3 100644 --- a/drivers/pci/endpoint/functions/pci-epf-test.c +++ b/drivers/pci/endpoint/functions/pci-epf-test.c @@ -826,30 +826,21 @@ static int pci_epf_test_core_init(struct pci_epf *epf) return 0; } -static const struct pci_epc_event_ops pci_epf_test_event_ops = { - .core_init = pci_epf_test_core_init, -}; - -static int pci_epf_test_notifier(struct notifier_block *nb, unsigned long val, - void *data) +int pci_epf_test_link_up(struct pci_epf *epf) { - struct pci_epf *epf = container_of(nb, struct pci_epf, nb); struct pci_epf_test *epf_test = epf_get_drvdata(epf); - switch (val) { - case LINK_UP: - queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler, - msecs_to_jiffies(1)); - break; - - default: - dev_err(&epf->dev, "Invalid EPF test notifier event\n"); - return NOTIFY_BAD; - } + queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler, + msecs_to_jiffies(1)); - return NOTIFY_OK; + return 0; } +static const struct pci_epc_event_ops pci_epf_test_event_ops = { + .core_init = pci_epf_test_core_init, + .link_up = pci_epf_test_link_up, +}; + static int pci_epf_test_alloc_space(struct pci_epf *epf) { struct pci_epf_test *epf_test = epf_get_drvdata(epf); @@ -976,12 +967,8 @@ static int pci_epf_test_bind(struct pci_epf *epf) if (ret) epf_test->dma_supported = false; - if (linkup_notifier || core_init_notifier) { - epf->nb.notifier_call = pci_epf_test_notifier; - pci_epc_register_notifier(epc, &epf->nb); - } else { + if (!linkup_notifier && !core_init_notifier) queue_work(kpcitest_workqueue, &epf_test->cmd_handler.work); - } return 0; } diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index ba54f17ae06f..5dac1496cf16 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -690,10 +690,19 @@ EXPORT_SYMBOL_GPL(pci_epc_remove_epf); */ void pci_epc_linkup(struct pci_epc *epc) { + struct pci_epf *epf; + if (!epc || IS_ERR(epc)) return; - atomic_notifier_call_chain(&epc->notifier, LINK_UP, NULL); + mutex_lock(&epc->list_lock); + list_for_each_entry(epf, &epc->pci_epf, list) { + mutex_lock(&epf->lock); + if (epf->event_ops->link_up) + epf->event_ops->link_up(epf); + mutex_unlock(&epf->lock); + } + mutex_unlock(&epc->list_lock); } EXPORT_SYMBOL_GPL(pci_epc_linkup); @@ -784,7 +793,6 @@ __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, mutex_init(&epc->lock); mutex_init(&epc->list_lock); INIT_LIST_HEAD(&epc->pci_epf); - ATOMIC_INIT_NOTIFIER_HEAD(&epc->notifier); device_initialize(&epc->dev); epc->dev.class = pci_epc_class; diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index fe729dfe509b..301bb0e53707 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -135,7 +135,6 @@ struct pci_epc_mem { * @group: configfs group representing the PCI EPC device * @lock: mutex to protect pci_epc ops * @function_num_map: bitmap to manage physical function number - * @notifier: used to notify EPF of any EPC events (like linkup) */ struct pci_epc { struct device dev; @@ -151,7 +150,6 @@ struct pci_epc { /* mutex to protect against concurrent access of EP controller */ struct mutex lock; unsigned long function_num_map; - struct atomic_notifier_head notifier; }; /** @@ -194,12 +192,6 @@ static inline void *epc_get_drvdata(struct pci_epc *epc) return dev_get_drvdata(&epc->dev); } -static inline int -pci_epc_register_notifier(struct pci_epc *epc, struct notifier_block *nb) -{ - return atomic_notifier_chain_register(&epc->notifier, nb); -} - struct pci_epc * __devm_pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, struct module *owner); diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h index a06f3b4c8bee..bc613f0df7e3 100644 --- a/include/linux/pci-epf.h +++ b/include/linux/pci-epf.h @@ -17,10 +17,6 @@ struct pci_epf; enum pci_epc_interface_type; -enum pci_notify_event { - LINK_UP, -}; - enum pci_barno { NO_BAR = -1, BAR_0, @@ -74,9 +70,11 @@ struct pci_epf_ops { /** * struct pci_epf_event_ops - Callbacks for capturing the EPC events * @core_init: Callback for the EPC initialization complete event + * @link_up: Callback for the EPC link up event */ struct pci_epc_event_ops { int (*core_init)(struct pci_epf *epf); + int (*link_up)(struct pci_epf *epf); }; /** @@ -135,7 +133,6 @@ struct pci_epf_bar { * @driver: the EPF driver to which this EPF device is bound * @id: Pointer to the EPF device ID * @list: to add pci_epf as a list of PCI endpoint functions to pci_epc - * @nb: notifier block to notify EPF of any EPC events (like linkup) * @lock: mutex to protect pci_epf_ops * @sec_epc: the secondary EPC device to which this EPF device is bound * @sec_epc_list: to add pci_epf as list of PCI endpoint functions to secondary @@ -164,7 +161,6 @@ struct pci_epf { struct pci_epf_driver *driver; const struct pci_epf_device_id *id; struct list_head list; - struct notifier_block nb; /* mutex to protect against concurrent access of pci_epf_ops */ struct mutex lock;