Hello,
On Thu, Jul 26, 2018 at 01:54:40PM +0100, Suzuki K Poulose wrote:
If the ETB is already enabled in sysfs mode, the ETB reports success even if a perf mode is requested. Fix this by checking the requested mode.
Cc: Mathieu Poirier mathieu.poirier@linaro.org Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com
drivers/hwtracing/coresight/coresight-etb10.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c index 306119e..e5808fd 100644 --- a/drivers/hwtracing/coresight/coresight-etb10.c +++ b/drivers/hwtracing/coresight/coresight-etb10.c @@ -148,8 +148,12 @@ static int etb_enable(struct coresight_device *csdev, u32 mode) return -EBUSY; /* Nothing to do, the tracer is already enabled. */
- if (val == CS_MODE_SYSFS)
goto out;
- if (val == CS_MODE_SYSFS) {
if (mode == CS_MODE_SYSFS)goto out;elsereturn -EBUSY;- }
How about:
if (val == CS_MODE_PERF) return -EBUSY;
+ /* Don't let perf disturb sysFS sessions */ + if (val == CS_MODE_SYSFS && mode = CS_MODE_PERF) + return -EBUSY; + /* Nothing to do, the tracer is already enabled. */ if (val == CS_MODE_SYSFS) goto out;
I just find it more readable that way.
Thanks, Mathieu
spin_lock_irqsave(&drvdata->spinlock, flags); etb_enable_hw(drvdata); -- 2.7.4