[PATCH v6 4/7] drm/sched: cleanup gpu_scheduler trace events

[Pierre-Eric Pelloux-Prayer]

Le 14/11/2024 à 15:56, Steven Rostedt a écrit :
> On Thu, 14 Nov 2024 11:01:07 +0100
> Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer at amd.com> wrote:
> 
>> A fence uniquely identify a job, so this commits updates the places
>> where a kernel pointer was used as an identifier by:
>>
>>     "fence=(context:%llu, seqno:%lld)"
>>
>> Signed-off-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer at amd.com>
>> ---
>>   .../gpu/drm/scheduler/gpu_scheduler_trace.h   | 39 +++++++++++--------
>>   1 file changed, 22 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h b/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h
>> index c4ec28540656..24358c4d5bbe 100644
>> --- a/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h
>> +++ b/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h
>> @@ -36,28 +36,29 @@ DECLARE_EVENT_CLASS(drm_sched_job,
>>   	    TP_PROTO(struct drm_sched_job *sched_job, struct drm_sched_entity *entity),
>>   	    TP_ARGS(sched_job, entity),
>>   	    TP_STRUCT__entry(
>> -			     __field(struct drm_sched_entity *, entity)
>> -			     __field(struct dma_fence *, fence)
>>   			     __string(name, sched_job->sched->name)
> 
> The __string() is a 4 byte meta field in the trace event structure. This
> means if you have a 64bit (8 byte) field following it, there will likely be
> a 4 byte hole between the two fields.
> 
> I would suggest swapping the name field with the id field, then you will
> have four 4 byte fields in a row (name, job_count, hw_job_count, dev),
> which should fill all the holes.

Good point, I'll swap them and check there's no hole.

Pierre-Eric

> 
> -- Steve
> 
> 
>>   			     __field(uint64_t, id)
>>   			     __field(u32, job_count)
>>   			     __field(int, hw_job_count)
>>   			     __string(dev, dev_name(sched_job->sched->dev))
>> +			     __field(uint64_t, fence_context)
>> +			     __field(uint64_t, fence_seqno)
>>   			     ),
>>   
>>   	    TP_fast_assign(
>> -			   __entry->entity = entity;
>>   			   __entry->id = sched_job->id;
>> -			   __entry->fence = &sched_job->s_fence->finished;
>>   			   __assign_str(name);
>>   			   __entry->job_count = spsc_queue_count(&entity->job_queue);
>>   			   __entry->hw_job_count = atomic_read(
>>   				   &sched_job->sched->credit_count);
>>   			   __assign_str(dev);
>> +			   __entry->fence_context = sched_job->s_fence->finished.context;
>> +			   __entry->fence_seqno = sched_job->s_fence->finished.seqno;
>> +
>>   			   ),
>> -	    TP_printk("dev=%s, entity=%p, id=%llu, fence=%p, ring=%s, job count:%u, hw job count:%d",
>> -		      __get_str(dev), __entry->entity, __entry->id,
>> -		      __entry->fence, __get_str(name),
>> +	    TP_printk("dev=%s, id=%llu, fence=(context:%llu, seqno:%lld), ring=%s, job count:%u, hw job count:%d",
>> +		      __get_str(dev), __entry->id,
>> +		      __entry->fence_context, __entry->fence_seqno, __get_str(name),
>>   		      __entry->job_count, __entry->hw_job_count)
>>   );
>>