This commit adds a document section in drm-uapi.rst about tracepoints, and mark the events gpu_scheduler_trace.h as stable uAPI. The goal is to explicitly state that tools can rely on the fields, formats and semantics of these events. Acked-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx> Acked-by: Maíra Canal <mcanal@xxxxxxxxxx> Signed-off-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@xxxxxxx> --- Documentation/gpu/drm-uapi.rst | 19 ++++++++++++++++ .../gpu/drm/scheduler/gpu_scheduler_trace.h | 22 +++++++++++++++++++ 2 files changed, 41 insertions(+) diff --git a/Documentation/gpu/drm-uapi.rst b/Documentation/gpu/drm-uapi.rst index b75cc9a70d1f..9603ac0f4c09 100644 --- a/Documentation/gpu/drm-uapi.rst +++ b/Documentation/gpu/drm-uapi.rst @@ -583,3 +583,22 @@ dma-buf interoperability Please see Documentation/userspace-api/dma-buf-alloc-exchange.rst for information on how dma-buf is integrated and exposed within DRM. + + +Trace events +============ + +See Documentation/trace/tracepoints.rst for information about using +Linux Kernel Tracepoints. +In the DRM subsystem, some events are considered stable uAPI to avoid +breaking tools (e.g.: GPUVis, umr) relying on them. Stable means that fields +cannot be removed, nor their formatting updated. Adding new fields is +possible, under the normal uAPI requirements. + +Stable uAPI events +------------------ + +From ``drivers/gpu/drm/scheduler/gpu_scheduler_trace.h`` + +.. kernel-doc:: drivers/gpu/drm/scheduler/gpu_scheduler_trace.h + :doc: uAPI trace events \ No newline at end of file diff --git a/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h b/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h index 8340c7c0c6b6..ec230e558961 100644 --- a/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h +++ b/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h @@ -33,6 +33,28 @@ #define TRACE_SYSTEM gpu_scheduler #define TRACE_INCLUDE_FILE gpu_scheduler_trace + +/** + * DOC: uAPI trace events + * + * ``drm_sched_job``, ``drm_run_job``, ``drm_sched_process_job``, + * and ``drm_sched_job_wait_dep`` are considered stable uAPI. + * + * Common trace events attributes: + * + * * ``id`` - this is &drm_sched_job->id. It uniquely idenfies a job + * inside a &struct drm_gpu_scheduler. + * + * * ``dev`` - the dev_name() of the device running the job. + * + * * ``ring`` - the hardware ring running the job. Together with ``dev`` it + * uniquely identifies where the job is going to be executed. + * + * * ``fence`` - the &dma_fence.context and the &dma_fence.seqno of + * &drm_sched_fence.finished + * + */ + #ifndef __TRACE_EVENT_GPU_SCHEDULER_PRINT_FN #define __TRACE_EVENT_GPU_SCHEDULER_PRINT_FN /* Similar to trace_print_array_seq but for fences. */ -- 2.43.0
