Re: [PATCH v5 06/10] coresight: etm-perf: Update to activate selected configuration

[Mathieu Poirier]

On Tue, Mar 16, 2021 at 06:03:56PM +0000, Mike Leach wrote:
> Add calls to activate the selected configuration as perf starts
> and stops the tracing session.
> 
> Signed-off-by: Mike Leach <mike.leach@xxxxxxxxxx>
> Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>

Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>

> ---
>  drivers/hwtracing/coresight/coresight-etm-perf.c | 14 +++++++++++++-
>  drivers/hwtracing/coresight/coresight-etm-perf.h |  2 ++
>  2 files changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
> index 66bda452a2f4..9128f59864a8 100644
> --- a/drivers/hwtracing/coresight/coresight-etm-perf.c
> +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
> @@ -196,6 +196,10 @@ static void free_event_data(struct work_struct *work)
>  	/* Free the sink buffers, if there are any */
>  	free_sink_buffer(event_data);
>  
> +	/* clear any configuration we were using */
> +	if (event_data->cfg_hash)
> +		cscfg_deactivate_config(event_data->cfg_hash);
> +
>  	for_each_cpu(cpu, mask) {
>  		struct list_head **ppath;
>  
> @@ -254,7 +258,7 @@ static void etm_free_aux(void *data)
>  static void *etm_setup_aux(struct perf_event *event, void **pages,
>  			   int nr_pages, bool overwrite)
>  {
> -	u32 id;
> +	u32 id, cfg_hash;
>  	int cpu = event->cpu;
>  	cpumask_t *mask;
>  	struct coresight_device *sink = NULL;
> @@ -271,6 +275,14 @@ static void *etm_setup_aux(struct perf_event *event, void **pages,
>  		sink = coresight_get_sink_by_id(id);
>  	}
>  
> +	/* check if user wants a coresight configuration selected */
> +	cfg_hash = (u32)((event->attr.config2 & GENMASK_ULL(63, 32)) >> 32);
> +	if (cfg_hash) {
> +		if (cscfg_activate_config(cfg_hash))
> +			goto err;
> +		event_data->cfg_hash = cfg_hash;
> +	}
> +
>  	mask = &event_data->mask;
>  
>  	/*
> diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.h b/drivers/hwtracing/coresight/coresight-etm-perf.h
> index ba617fe2217e..468f7799ab4f 100644
> --- a/drivers/hwtracing/coresight/coresight-etm-perf.h
> +++ b/drivers/hwtracing/coresight/coresight-etm-perf.h
> @@ -49,12 +49,14 @@ struct etm_filters {
>   * @work:		Handle to free allocated memory outside IRQ context.
>   * @mask:		Hold the CPU(s) this event was set for.
>   * @snk_config:		The sink configuration.
> + * @cfg_hash:		The hash id of any coresight config selected.
>   * @path:		An array of path, each slot for one CPU.
>   */
>  struct etm_event_data {
>  	struct work_struct work;
>  	cpumask_t mask;
>  	void *snk_config;
> +	u32 cfg_hash;
>  	struct list_head * __percpu *path;
>  };
>  
> -- 
> 2.17.1
>