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

[Philipp Stanner]

On Thu, 2024-11-14 at 11:01 +0100, Pierre-Eric Pelloux-Prayer wrote:
> A fence uniquely identify a job, so this commits updates the places

s/identify/identifies

> where a kernel pointer was used as an identifier by:

But better sth like this:

"Currently, the scheduler's tracing infrastructure uses the job's
dma_fence and the drm_sched_entity the job belongs to. The dma_fence
alone, however, already uniquely identifies a job.

Use the dma_fence's context and sequence number exclusively identify a
job in debug prints like so: 

> 
>    "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)
>  			     __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)
>  );
>  
> @@ -75,37 +76,41 @@ TRACE_EVENT(drm_sched_process_job,
>  	    TP_PROTO(struct drm_sched_fence *fence),
>  	    TP_ARGS(fence),
>  	    TP_STRUCT__entry(
> -		    __field(struct dma_fence *, fence)
> +		    __field(uint64_t, fence_context)
> +		    __field(uint64_t, fence_seqno)
>  		    ),
>  
>  	    TP_fast_assign(
> -		    __entry->fence = &fence->finished;
> +		    __entry->fence_context = fence-
> >finished.context;
> +		    __entry->fence_seqno = fence->finished.seqno;
>  		    ),
> -	    TP_printk("fence=%p signaled", __entry->fence)
> +	    TP_printk("fence=(context:%llu, seqno:%lld) signaled",
> +		      __entry->fence_context, __entry->fence_seqno)
>  );
>  
>  TRACE_EVENT(drm_sched_job_wait_dep,
>  	    TP_PROTO(struct drm_sched_job *sched_job, struct
> dma_fence *fence),
>  	    TP_ARGS(sched_job, fence),
>  	    TP_STRUCT__entry(
> -			     __string(name, sched_job->sched->name)
> +			     __field(uint64_t, fence_context)
> +			     __field(uint64_t, fence_seqno)
>  			     __field(uint64_t, id)
>  			     __field(struct dma_fence *, fence)
>  			     __field(uint64_t, ctx)
> -			     __field(unsigned, seqno)
> +			     __field(uint64_t, seqno)
>  			     ),
>  
>  	    TP_fast_assign(
> -			   __assign_str(name);
> +			   __entry->fence_context = sched_job-
> >s_fence->finished.context;
> +			   __entry->fence_seqno = sched_job-
> >s_fence->finished.seqno;
>  			   __entry->id = sched_job->id;
>  			   __entry->fence = fence;
>  			   __entry->ctx = fence->context;
>  			   __entry->seqno = fence->seqno;
>  			   ),
> -	    TP_printk("job ring=%s, id=%llu, depends fence=%p,
> context=%llu, seq=%u",
> -		      __get_str(name), __entry->id,
> -		      __entry->fence, __entry->ctx,
> -		      __entry->seqno)
> +	    TP_printk("fence=(context:%llu, seqno:%lld), id=%llu,
> dependencies:{(context:%llu, seqno:%lld)}",
> +		      __entry->fence_context, __entry->fence_seqno,
> __entry->id,
> +		      __entry->ctx, __entry->seqno)
>  );
>  
>  #endif