From: Leo Yan <leo.yan@linaro.org>
To: Mathieu Poirier <mathieu.poirier@linaro.org>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Mike Leach <mike.leach@linaro.org>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org
Cc: Leo Yan <leo.yan@linaro.org>
Subject: [PATCH v2 RESEND 1/4] coresight: etm4x: Add lock for reading virtual context ID comparator
Date: Fri, 4 Feb 2022 23:24:00 +0800 [thread overview]
Message-ID: <20220204152403.71775-2-leo.yan@linaro.org> (raw)
In-Reply-To: <20220204152403.71775-1-leo.yan@linaro.org>
Updates to the values and the index are protected via the spinlock.
Ensure we use the same lock to read the value safely.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
drivers/hwtracing/coresight/coresight-etm4x-sysfs.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
index 10ef2a29006e..2f3b4eef8261 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
@@ -2111,7 +2111,9 @@ static ssize_t vmid_val_show(struct device *dev,
struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
struct etmv4_config *config = &drvdata->config;
+ spin_lock(&drvdata->spinlock);
val = (unsigned long)config->vmid_val[config->vmid_idx];
+ spin_unlock(&drvdata->spinlock);
return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
}
--
2.25.1
next prev parent reply other threads:[~2022-02-04 15:24 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-04 15:23 [PATCH v2 RESEND 0/4] coresight: etm: Correct PID tracing for non-root namespace Leo Yan
2022-02-04 15:24 ` Leo Yan [this message]
2022-02-09 5:47 ` [PATCH v2 RESEND 1/4] coresight: etm4x: Add lock for reading virtual context ID comparator Suzuki K Poulose
2022-02-09 9:33 ` Leo Yan
2022-02-09 9:42 ` Suzuki K Poulose
2022-02-09 16:58 ` Mathieu Poirier
2022-02-04 15:24 ` [PATCH v2 RESEND 2/4] coresight: etm4x: Don't use virtual contextID for non-root PID namespace Leo Yan
2022-02-04 15:24 ` [PATCH v2 RESEND 3/4] coresight: etm4x: Don't trace PID " Leo Yan
2022-02-04 15:24 ` [PATCH v2 RESEND 4/4] coresight: etm3x: " Leo Yan
2022-02-25 13:52 ` [PATCH v2 RESEND 0/4] coresight: etm: Correct PID tracing for non-root namespace Suzuki K Poulose
2022-02-28 6:17 ` Leo Yan
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