[igt-dev] [PATCH i-g-t 2/2] intel_gpu_overlay: Update for class:instance engine tracepoints

[Lionel Landwerlin]

On 05/06/18 17:50, Tvrtko Ursulin wrote:
> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>
> A miminal hack to parse the new tracepoint format and invent new "ring
> id's" based on engine class and instance.
>
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Cc: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
> ---
>   overlay/gpu-perf.c | 36 ++++++++++++++++++++++++++++--------
>   1 file changed, 28 insertions(+), 8 deletions(-)
>
> diff --git a/overlay/gpu-perf.c b/overlay/gpu-perf.c
> index ea3480050ab9..e77125672088 100644
> --- a/overlay/gpu-perf.c
> +++ b/overlay/gpu-perf.c
> @@ -85,7 +85,8 @@ struct tracepoint {
>   
>   	int device_field;
>   	int ctx_field;
> -	int ring_field;
> +	int class_field;
> +	int instance_field;
>   	int seqno_field;
>   	int global_seqno_field;
>   	int plane_field;
> @@ -151,8 +152,10 @@ tracepoint_id(int tp_id)
>   				tp->device_field = f;
>   			} else if (!strcmp(tp->fields[f].name, "ctx")) {
>   				tp->ctx_field = f;
> -			} else if (!strcmp(tp->fields[f].name, "ring")) {
> -				tp->ring_field = f;
> +			} else if (!strcmp(tp->fields[f].name, "class")) {
> +				tp->class_field = f;
> +			} else if (!strcmp(tp->fields[f].name, "instance")) {
> +				tp->instance_field = f;

That looks good to me. We only support the most recent kernel?

>   			} else if (!strcmp(tp->fields[f].name, "seqno")) {
>   				tp->seqno_field = f;
>   			} else if (!strcmp(tp->fields[f].name, "global_seqno")) {
> @@ -175,6 +178,23 @@ tracepoint_id(int tp_id)
>   			     tracepoints[tp_id].fields[			\
>   				     tracepoints[tp_id].field_name##_field].offset))
>   
> +#define READ_TP_FIELD_U16(sample, tp_id, field_name)			\
> +	(*(const uint16_t *)((sample)->tracepoint_data +		\
> +			     tracepoints[tp_id].fields[			\
> +				     tracepoints[tp_id].field_name##_field].offset))
> +
> +#define GET_RING_ID(sample, tp_id) \
> +({ \
> +	unsigned char class, instance, ring; \
> +\
> +	class = READ_TP_FIELD_U16(sample, tp_id, class); \
> +	instance = READ_TP_FIELD_U16(sample, tp_id, instance); \
> +\
> +	ring = class * 2 + instance; \

Do you want to make it clear that we cannot have more than 2 instances 
per class?

> +\
> +	ring; \
> +})
> +
>   static int perf_tracepoint_open(struct gpu_perf *gp, int tp_id,
>   				int (*func)(struct gpu_perf *, const void *))
>   {
> @@ -313,7 +333,7 @@ static int request_add(struct gpu_perf *gp, const void *event)
>   	if (comm == NULL)
>   		return 0;
>   
> -	comm->nr_requests[READ_TP_FIELD_U32(sample, TP_GEM_REQUEST_ADD, ring)]++;
> +	comm->nr_requests[GET_RING_ID(sample, TP_GEM_REQUEST_ADD)]++;
>   	return 1;
>   }
>   
> @@ -329,7 +349,7 @@ static int ctx_switch(struct gpu_perf *gp, const void *event)
>   {
>   	const struct sample_event *sample = event;
>   
> -	gp->ctx_switch[READ_TP_FIELD_U32(sample, TP_GEM_RING_SWITCH_CONTEXT, ring)]++;
> +	gp->ctx_switch[GET_RING_ID(sample, TP_GEM_RING_SWITCH_CONTEXT)]++;
>   	return 1;
>   }
>   
> @@ -367,8 +387,8 @@ static int wait_begin(struct gpu_perf *gp, const void *event)
>   	wait->context = READ_TP_FIELD_U32(sample, TP_GEM_REQUEST_WAIT_BEGIN, ctx);
>   	wait->seqno = READ_TP_FIELD_U32(sample, TP_GEM_REQUEST_WAIT_BEGIN, seqno);
>   	wait->time = sample->time;
> -	wait->next = gp->wait[READ_TP_FIELD_U32(sample, TP_GEM_REQUEST_WAIT_BEGIN, ring)];
> -	gp->wait[READ_TP_FIELD_U32(sample, TP_GEM_REQUEST_WAIT_BEGIN, ring)] = wait;
> +	wait->next = gp->wait[GET_RING_ID(sample, TP_GEM_REQUEST_WAIT_BEGIN)];
> +	gp->wait[GET_RING_ID(sample, TP_GEM_REQUEST_WAIT_BEGIN)] = wait;
>   
>   	return 0;
>   }
> @@ -377,7 +397,7 @@ static int wait_end(struct gpu_perf *gp, const void *event)
>   {
>   	const struct sample_event *sample = event;
>   	struct gpu_perf_time *wait, **prev;
> -	uint32_t engine = READ_TP_FIELD_U32(sample, TP_GEM_REQUEST_WAIT_END, ring);
> +	uint32_t engine = GET_RING_ID(sample, TP_GEM_REQUEST_WAIT_END);
>   	uint32_t context = READ_TP_FIELD_U32(sample, TP_GEM_REQUEST_WAIT_END, ctx);
>   	uint32_t seqno = READ_TP_FIELD_U32(sample, TP_GEM_REQUEST_WAIT_END, seqno);
>