lkml.org 
[lkml]   [2021]   [Dec]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 1/4] coresight: etm4x: Add lock for reading virtual context ID comparator
Date
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
\
 
 \ /
  Last update: 2021-12-13 13:14    [W:0.087 / U:0.368 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site