From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 171C51C760A for ; Fri, 20 Dec 2024 10:45:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734691544; cv=none; b=S1xkWXqLh69PwZw/Wo+DTvv4pnLdozNJ0xs5mry4mE0uuP/FTQL+oBM2uV67n2YECwNQo7dYK9MKiYif4ut4v906i2A96jBDlImFNhqwIwgQIvhnkHdHT/7Ip+U05jvHZW/dhFIuSLHqloZPOrhdEzbeiUpznkXMLY1Eg8StuBU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734691544; c=relaxed/simple; bh=0EEhdnGXDw1zRHxeaYocdTSr2A1nIKdEtkk+xOzG9r8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=QwdkN/WaCKsN38v1GAzUHSeOjnLFH8+F4n3rPbApXSojT2OivmUPRQeUk2a+02cv/qtGQwMhfmWZsrkbyYzjKjqbwj+dVOjGhC/F5Rfx5FZKhVvxkUFgukts82GIPh+dsVQvES/cL9xLPPnObT6A8KqxCTs74+MIIE2sQp+8VjQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 A16801480; Fri, 20 Dec 2024 02:46:10 -0800 (PST) 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 82AB93F720; Fri, 20 Dec 2024 02:45:40 -0800 (PST) From: Yeoreum Yun To: suzuki.poulose@arm.com, james.clark@linaro.org, alexander.shishkin@linux.intel.com, bigeasy@linutronix.de, clrkwllms@kernel.org, rostedt@goodmis.org, mike.leach@linaro.org Cc: coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, Yeoreum Yun Subject: [PATCH v4 6/9] coresight-funnel: change funnel_drvdata spinlock's type to raw_spinlock_t Date: Fri, 20 Dec 2024 10:45:18 +0000 Message-Id: <20241220104521.809071-8-yeoreum.yun@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241220104521.809071-1-yeoreum.yun@arm.com> References: <20241220104521.809071-1-yeoreum.yun@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In coresight-funnel drivers, cti_drvdata->spinlock can be held during __schedule() by perf_event_task_sched_out()/in(). Since funnel_drvdata->spinlock type is spinlock_t and perf_event_task_sched_out()/in() is called after acquiring rq_lock, which is raw_spinlock_t (an unsleepable lock), this poses an issue in PREEMPT_RT kernel where spinlock_t is sleepable. To address this, change type funnel_drvdata->spinlock in coresight-funnel drivers, which can be called by perf_event_task_sched_out()/in(), from spinlock_t to raw_spinlock_t. Reviewed-by: James Clark Reviewed-by: Mike Leach Signed-off-by: Yeoreum Yun --- drivers/hwtracing/coresight/coresight-funnel.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-funnel.c b/drivers/hwtracing/coresight/coresight-funnel.c index 33efe1acbef7..a566c8854327 100644 --- a/drivers/hwtracing/coresight/coresight-funnel.c +++ b/drivers/hwtracing/coresight/coresight-funnel.c @@ -47,7 +47,7 @@ struct funnel_drvdata { struct clk *pclk; struct coresight_device *csdev; unsigned long priority; - spinlock_t spinlock; + raw_spinlock_t spinlock; }; static int dynamic_funnel_enable_hw(struct funnel_drvdata *drvdata, int port) @@ -85,7 +85,7 @@ static int funnel_enable(struct coresight_device *csdev, unsigned long flags; bool first_enable = false; - spin_lock_irqsave(&drvdata->spinlock, flags); + raw_spin_lock_irqsave(&drvdata->spinlock, flags); if (atomic_read(&in->dest_refcnt) == 0) { if (drvdata->base) rc = dynamic_funnel_enable_hw(drvdata, in->dest_port); @@ -94,7 +94,7 @@ static int funnel_enable(struct coresight_device *csdev, } if (!rc) atomic_inc(&in->dest_refcnt); - spin_unlock_irqrestore(&drvdata->spinlock, flags); + raw_spin_unlock_irqrestore(&drvdata->spinlock, flags); if (first_enable) dev_dbg(&csdev->dev, "FUNNEL inport %d enabled\n", @@ -129,13 +129,13 @@ static void funnel_disable(struct coresight_device *csdev, unsigned long flags; bool last_disable = false; - spin_lock_irqsave(&drvdata->spinlock, flags); + raw_spin_lock_irqsave(&drvdata->spinlock, flags); if (atomic_dec_return(&in->dest_refcnt) == 0) { if (drvdata->base) dynamic_funnel_disable_hw(drvdata, in->dest_port); last_disable = true; } - spin_unlock_irqrestore(&drvdata->spinlock, flags); + raw_spin_unlock_irqrestore(&drvdata->spinlock, flags); if (last_disable) dev_dbg(&csdev->dev, "FUNNEL inport %d disabled\n", @@ -266,7 +266,7 @@ static int funnel_probe(struct device *dev, struct resource *res) } dev->platform_data = pdata; - spin_lock_init(&drvdata->spinlock); + raw_spin_lock_init(&drvdata->spinlock); desc.type = CORESIGHT_DEV_TYPE_LINK; desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_MERG; desc.ops = &funnel_cs_ops; -- LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}