From nobody Wed Dec 17 21:41:01 2025 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id EF72C205E12 for ; Mon, 16 Dec 2024 11:50:27 +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=1734349830; cv=none; b=ZbuckE8R1sTyNHuuAcpEYzJ1dV+ukK7nrzANzr4CCVvE4zuVCwm3E1ceVot8tIYauLhfx2ZparJtkajAiWTe67Ef0P+RaXHYCORUv38XCMsM3cAIdcmEBz6UFVohCkFEYo+QB+MKuo0Zomugmlrw/RlGgjcY3NIcxKkUk4nunb4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734349830; c=relaxed/simple; bh=k/CmxdFjeRb0Df4HhwzVzyYnBGVxJt7pqMM8EOtOmTI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=G1XowZXoFBatPvltYC4+3cnPCxqbOYy31SvcJtvW0beRtti38d3fUjnNgDsNG+9Bs8saDrw1l3+PHmDrOswwA7QUajjlL+MnzuflxKm8iI8t1X7kVaClFodJhL/oz3R5ZCTSbVzjIC1NQhgcPzP9efI4+r9QXVW6ggsW66Z+DQI= 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 686BC11FB; Mon, 16 Dec 2024 03:50:55 -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 4E7D63F58B; Mon, 16 Dec 2024 03:50:25 -0800 (PST) From: Yeoreum Yun To: suzuki.poulose@arm.com, mike.leach@linaro.org, james.clark@linaro.org, alexander.shishkin@linux.intel.com, bigeasy@linutronix.de, clrkwllms@kernel.org, rostedt@goodmis.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 v3 7/9] coresight-replicator: change replicator_drvdata spinlock's type to raw_spinlock_t Date: Mon, 16 Dec 2024 11:50:04 +0000 Message-Id: <20241216115006.415861-8-yeoreum.yun@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241216115006.415861-1-yeoreum.yun@arm.com> References: <20241216115006.415861-1-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: quoted-printable Content-Type: text/plain; charset="utf-8" In coresight-replicator drivers, replicator_drvdata->spinlock can be held during __schedule() by perf_event_task_sched_out()/in(). Since replicator_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 replicator_drvdata->spinlock in coresight-replicator drivers, which can be called by perf_event_task_sched_out()/in(), from spinlock_t to raw_spinlock_t. Signed-off-by: Yeoreum Yun Reviewed-by: Mike Leach --- drivers/hwtracing/coresight/coresight-replicator.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/h= wtracing/coresight/coresight-replicator.c index 0fba87de6d1a..7d36fe2176cc 100644 --- a/drivers/hwtracing/coresight/coresight-replicator.c +++ b/drivers/hwtracing/coresight/coresight-replicator.c @@ -41,7 +41,7 @@ struct replicator_drvdata { struct clk *atclk; struct clk *pclk; struct coresight_device *csdev; - spinlock_t spinlock; + raw_spinlock_t spinlock; bool check_idfilter_val; }; =20 @@ -125,7 +125,7 @@ static int replicator_enable(struct coresight_device *c= sdev, unsigned long flags; bool first_enable =3D false; =20 - spin_lock_irqsave(&drvdata->spinlock, flags); + raw_spin_lock_irqsave(&drvdata->spinlock, flags); if (atomic_read(&out->src_refcnt) =3D=3D 0) { if (drvdata->base) rc =3D dynamic_replicator_enable(drvdata, in->dest_port, @@ -135,7 +135,7 @@ static int replicator_enable(struct coresight_device *c= sdev, } if (!rc) atomic_inc(&out->src_refcnt); - spin_unlock_irqrestore(&drvdata->spinlock, flags); + raw_spin_unlock_irqrestore(&drvdata->spinlock, flags); =20 if (first_enable) dev_dbg(&csdev->dev, "REPLICATOR enabled\n"); @@ -179,14 +179,14 @@ static void replicator_disable(struct coresight_devic= e *csdev, unsigned long flags; bool last_disable =3D false; =20 - spin_lock_irqsave(&drvdata->spinlock, flags); + raw_spin_lock_irqsave(&drvdata->spinlock, flags); if (atomic_dec_return(&out->src_refcnt) =3D=3D 0) { if (drvdata->base) dynamic_replicator_disable(drvdata, in->dest_port, out->src_port); last_disable =3D true; } - spin_unlock_irqrestore(&drvdata->spinlock, flags); + raw_spin_unlock_irqrestore(&drvdata->spinlock, flags); =20 if (last_disable) dev_dbg(&csdev->dev, "REPLICATOR disabled\n"); @@ -277,7 +277,7 @@ static int replicator_probe(struct device *dev, struct = resource *res) } dev->platform_data =3D pdata; =20 - spin_lock_init(&drvdata->spinlock); + raw_spin_lock_init(&drvdata->spinlock); desc.type =3D CORESIGHT_DEV_TYPE_LINK; desc.subtype.link_subtype =3D CORESIGHT_DEV_SUBTYPE_LINK_SPLIT; desc.ops =3D &replicator_cs_ops; --=20 LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}