From mboxrd@z Thu Jan 1 00:00:00 1970 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EDA02F43848 for ; Wed, 15 Apr 2026 16:56:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=dnfKYi0dOWMJdbUjuwPPxscgjg63xAF2RMyVBxA5/2s=; b=jpwlkCIsSgrO5GNgBu1kXG5gvd n8Wlp66UgtkPK9q6OYJc8RjvctJzpJakmsp0ce+x7/mgrND4W1KPIfpLsPd0w4cAU70HhKTgRvK3t SJdPA1DnoK6UG/I/X82GIfDgXVl62sh2+Grv4vSINrsY2YUxN35gwrIJYcd4ai0S54q8kBkOsCEeo AWXD9g+5thtm5CTct79psoEwpCY4ZKzvWlVsRUyMpgi3iNuwDINc82zSqh+idilHq//0oPN7tqFQF seq5RSOBctQoY2w7ZQ53cl2ms0F7NPaRUmmIMtcphSnZPF2QwMZbuqm/i7dkysmShHd9NUzDYSn7/ rN8nAcNQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wD3X8-00000001Pu6-20xh; Wed, 15 Apr 2026 16:56:10 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wD3Wx-00000001Pi5-1cn5 for linux-arm-kernel@lists.infradead.org; Wed, 15 Apr 2026 16:56:00 +0000 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 4176732FB; Wed, 15 Apr 2026 09:55:53 -0700 (PDT) Received: from e129823.cambridge.arm.com (e129823.arm.com [10.1.197.6]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 15A013F7D8; Wed, 15 Apr 2026 09:55:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1776272158; bh=dBlTY/m9WM8JFBhitEJBbiQCl2HVEF88g590hzectJQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vfz2VPZ+E4+S/V8gmtkEd82xHkMvjDsBPzkeQ5dRYm453U+QxKRxSfCeyv3ItuxOg 6yaNV4eyCAh0PJg1gnW8nbgNtOHBZXQMzgTonqD2jc8eMOT7+yWe2mfoISgCHzlASk QRDmLZ2RpWTLdV83NvqBxDGJUCJLTa8oeTA9iCPc= From: Yeoreum Yun To: coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: suzuki.poulose@arm.com, mike.leach@arm.com, james.clark@linaro.org, alexander.shishkin@linux.intel.com, leo.yan@arm.com, jie.gan@oss.qualcomm.com, Yeoreum Yun Subject: [PATCH v5 12/12] coresight: etm3x: remove redundant call etm_enable_hw() with hotplug Date: Wed, 15 Apr 2026 17:55:28 +0100 Message-Id: <20260415165528.3369607-13-yeoreum.yun@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260415165528.3369607-1-yeoreum.yun@arm.com> References: <20260415165528.3369607-1-yeoreum.yun@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260415_095559_468410_0D858301 X-CRM114-Status: GOOD ( 12.48 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The cpu_online_mask is set at the CPUHP_BRINGUP_CPU step. In other words, if etm4_enable_sysfs() is called between CPUHP_BRINGUP_CPU and CPUHP_AP_ARM_CORESIGHT_STARTING, etm_enable_hw() may be invoked in etm_enable_sysfs_smp_call() and then executed again in etm_starting_cpu(). To remove this redundant call, take the hotplug lock before executing etm_enable_sysfs_smp_call(). Signed-off-by: Yeoreum Yun --- .../coresight/coresight-etm3x-core.c | 24 +++++++++---------- 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etm3x-core.c b/drivers/hwtracing/coresight/coresight-etm3x-core.c index 706a4c7a40df..8bf7ae276096 100644 --- a/drivers/hwtracing/coresight/coresight-etm3x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm3x-core.c @@ -521,26 +521,26 @@ static int etm_enable_sysfs(struct coresight_device *csdev, struct coresight_pat struct etm_enable_arg arg = { }; int ret; + arg.drvdata = drvdata; + arg.traceid = path->trace_id; + + raw_spin_lock(&drvdata->spinlock); + arg.config = drvdata->config; + raw_spin_unlock(&drvdata->spinlock); /* * Configure the ETM only if the CPU is online. If it isn't online * hw configuration will take place on the local CPU during bring up. */ - if (cpu_online(drvdata->cpu)) { - arg.drvdata = drvdata; - arg.traceid = path->trace_id; - - raw_spin_lock(&drvdata->spinlock); - arg.config = drvdata->config; - raw_spin_unlock(&drvdata->spinlock); - + cpus_read_lock(); ret = smp_call_function_single(drvdata->cpu, etm_enable_sysfs_smp_call, &arg, 1); - if (!ret) - ret = arg.rc; - } else { + cpus_read_unlock(); + + if (!ret) + ret = arg.rc; + else ret = -ENODEV; - } if (!ret) dev_dbg(&csdev->dev, "ETM tracing enabled\n"); -- LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}