Re: [PATCH 05/13] coresight: etm3: Add support for handling errors

Mathieu Poirier
2018-08-15T19:35:03Z

On Mon, Aug 06, 2018 at 02:41:47PM +0100, Suzuki K Poulose wrote:
> Add support for reporting errors back from the SMP cross
> function call for enabling ETM.
>
> Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> ---
> drivers/hwtracing/coresight/coresight-etm3x.c | 42 ++++++++++++++++++---------
> 1 file changed, 28 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
> index 9ce8fba..771691c 100644
> --- a/drivers/hwtracing/coresight/coresight-etm3x.c
> +++ b/drivers/hwtracing/coresight/coresight-etm3x.c
> @@ -355,11 +355,10 @@ static int etm_parse_event_config(struct etm_drvdata *drvdata,
> return 0;
> }
>
> -static void etm_enable_hw(void *info)
> +static int etm_enable_hw(struct etm_drvdata *drvdata)
> {
> int i;
> u32 etmcr;
> - struct etm_drvdata *drvdata = info;
> struct etm_config *config = &drvdata->config;
>
> CS_UNLOCK(drvdata->base);
> @@ -421,6 +420,21 @@ static void etm_enable_hw(void *info)
> CS_LOCK(drvdata->base);
>
> dev_dbg(drvdata->dev, "cpu: %d enable smp call done\n", drvdata->cpu);
> + return 0;
> +}
> +
> +struct etm_enable_arg {
> + struct etm_drvdata *drvdata;
> + int rc;
> +}

This doesn't compile a ';' is missing.

> +
> +static void etm_enable_hw_smp_call(void *info)
> +{
> + struct etm_enable_arg *arg = info;
> +
> + if (WARN_ON(!arg))
> + return;
> + arg->rc = etm_enable_hw(arg->drvdata);
> }
>
> static int etm_cpu_id(struct coresight_device *csdev)
> @@ -475,14 +489,13 @@ static int etm_enable_perf(struct coresight_device *csdev,
> /* Configure the tracer based on the session's specifics */
> etm_parse_event_config(drvdata, event);
> /* And enable it */
> - etm_enable_hw(drvdata);
> -
> - return 0;
> + return etm_enable_hw(drvdata);
> }
>
> static int etm_enable_sysfs(struct coresight_device *csdev)
> {
> struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
> + struct etm_enable_arg arg = { 0 };
> int ret;
>
> spin_lock(&drvdata->spinlock);
> @@ -492,20 +505,21 @@ static int etm_enable_sysfs(struct coresight_device *csdev)
> * hw configuration will take place on the local CPU during bring up.
> */
> if (cpu_online(drvdata->cpu)) {
> + arg.drvdata = drvdata;
> ret = smp_call_function_single(drvdata->cpu,
> - etm_enable_hw, drvdata, 1);
> - if (ret)
> - goto err;
> + etm_enable_hw_smp_call, &arg, 1);
> + if (!ret)
> + ret = arg.rc;
> + if (!ret)
> + drvdata->sticky_enable = true;
> + } else {
> + ret = -ENODEV;
> }
>
> - drvdata->sticky_enable = true;
> spin_unlock(&drvdata->spinlock);
>
> - dev_dbg(drvdata->dev, "ETM tracing enabled\n");
> - return 0;
> -
> -err:
> - spin_unlock(&drvdata->spinlock);
> + if (!ret)
> + dev_dbg(drvdata->dev, "ETM tracing enabled\n");
> return ret;
> }
>
> --
> 2.7.4
>