From patchwork Mon Jun 5 12:37:08 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yicong Yang X-Patchwork-Id: 13267319 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 F1398C77B73 for ; Mon, 5 Jun 2023 12:38:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230324AbjFEMix (ORCPT ); Mon, 5 Jun 2023 08:38:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34910 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232068AbjFEMir (ORCPT ); Mon, 5 Jun 2023 08:38:47 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5FDA898; Mon, 5 Jun 2023 05:38:40 -0700 (PDT) Received: from canpemm500009.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4QZY1p10MzzqTYb; Mon, 5 Jun 2023 20:33:50 +0800 (CST) Received: from localhost.localdomain (10.50.163.32) by canpemm500009.china.huawei.com (7.192.105.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Mon, 5 Jun 2023 20:38:35 +0800 From: Yicong Yang To: , , , CC: , , , , , Subject: [PATCH] hwtracing: hisi_ptt: Fix potential sleep in atomic context Date: Mon, 5 Jun 2023 20:37:08 +0800 Message-ID: <20230605123708.9740-1-yangyicong@huawei.com> X-Mailer: git-send-email 2.31.0 MIME-Version: 1.0 X-Originating-IP: [10.50.163.32] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To canpemm500009.china.huawei.com (7.192.105.203) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Yicong Yang We're using pci_irq_vector() to obtain the interrupt number and then bind it to the CPU start perf under the protection of spinlock in pmu::start(). pci_irq_vector() might sleep and use it in an atomic context is problematic. This patch cached the interrupt number in the probe() and uses the cached data instead to avoid potential sleep. Fixes: ff0de066b463 ("hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tune and Trace device") Signed-off-by: Yicong Yang --- drivers/hwtracing/ptt/hisi_ptt.c | 12 +++++------- drivers/hwtracing/ptt/hisi_ptt.h | 2 ++ 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c index 30f1525639b5..0915820f17ba 100644 --- a/drivers/hwtracing/ptt/hisi_ptt.c +++ b/drivers/hwtracing/ptt/hisi_ptt.c @@ -341,13 +341,12 @@ static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt) if (ret < 0) return ret; - ret = devm_request_threaded_irq(&pdev->dev, - pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), + ret = devm_request_threaded_irq(&pdev->dev, hisi_ptt->trace_irq, NULL, hisi_ptt_isr, 0, DRV_NAME, hisi_ptt); if (ret) { pci_err(pdev, "failed to request irq %d, ret = %d\n", - pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), ret); + hisi_ptt->trace_irq, ret); return ret; } @@ -757,8 +756,7 @@ static void hisi_ptt_pmu_start(struct perf_event *event, int flags) * core in event_function_local(). If CPU passed is offline we'll fail * here, just log it since we can do nothing here. */ - ret = irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ), - cpumask_of(cpu)); + ret = irq_set_affinity(hisi_ptt->trace_irq, cpumask_of(cpu)); if (ret) dev_warn(dev, "failed to set the affinity of trace interrupt\n"); @@ -953,6 +951,7 @@ static int hisi_ptt_probe(struct pci_dev *pdev, } hisi_ptt->iobase = pcim_iomap_table(pdev)[2]; + hisi_ptt->trace_irq = pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ); ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64)); if (ret) { @@ -1018,8 +1017,7 @@ static int hisi_ptt_cpu_teardown(unsigned int cpu, struct hlist_node *node) * Also make sure the interrupt bind to the migrated CPU as well. Warn * the user on failure here. */ - if (irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ), - cpumask_of(target))) + if (irq_set_affinity(hisi_ptt->trace_irq, cpumask_of(target))) dev_warn(dev, "failed to set the affinity of trace interrupt\n"); hisi_ptt->trace_ctrl.on_cpu = target; diff --git a/drivers/hwtracing/ptt/hisi_ptt.h b/drivers/hwtracing/ptt/hisi_ptt.h index 5beb1648c93a..948a4c423152 100644 --- a/drivers/hwtracing/ptt/hisi_ptt.h +++ b/drivers/hwtracing/ptt/hisi_ptt.h @@ -166,6 +166,7 @@ struct hisi_ptt_pmu_buf { * @pdev: pci_dev of this PTT device * @tune_lock: lock to serialize the tune process * @pmu_lock: lock to serialize the perf process + * @trace_irq: interrupt number used by trace * @upper_bdf: the upper BDF range of the PCI devices managed by this PTT device * @lower_bdf: the lower BDF range of the PCI devices managed by this PTT device * @port_filters: the filter list of root ports @@ -180,6 +181,7 @@ struct hisi_ptt { struct pci_dev *pdev; struct mutex tune_lock; spinlock_t pmu_lock; + int trace_irq; u32 upper_bdf; u32 lower_bdf;