[PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Rob Clark]

On Sat, Apr 9, 2022 at 7:33 AM Christian König <christian.koenig at amd.com> wrote:
>
> Am 08.04.22 um 23:12 schrieb Chia-I Wu:
> > In practice, trace_dma_fence_init is good enough and almost no driver
> > calls trace_dma_fence_emit.  But this is still more correct in theory.
>
> Well, the reason why basically no driver is calling this is because it
> is pretty much deprecated.
>
> We do have a case in the GPU scheduler where it makes sense to distinct
> between init and emit, but it doesn't really matter for drivers.
>
> So I'm not sure if it's a good idea to add that here.

visualization can't easily differentiate between drivers/timelines
where the split matters and ones where it doesn't..  IMO it is better
to just have the extra trace even in the cases where it comes at the
same time as the init trace

BR,
-R

> Regards,
> Christian.
>
> >
> > Signed-off-by: Chia-I Wu <olvaffe at gmail.com>
> > Cc: Rob Clark <robdclark at chromium.org>
> > ---
> >   drivers/gpu/drm/msm/msm_gpu.c | 2 ++
> >   1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> > index faf0c242874e..a82193f41ea2 100644
> > --- a/drivers/gpu/drm/msm/msm_gpu.c
> > +++ b/drivers/gpu/drm/msm/msm_gpu.c
> > @@ -15,6 +15,7 @@
> >   #include <linux/string_helpers.h>
> >   #include <linux/devcoredump.h>
> >   #include <linux/sched/task.h>
> > +#include <trace/events/dma_fence.h>
> >
> >   /*
> >    * Power Management:
> > @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
> >       gpu->active_submits++;
> >       mutex_unlock(&gpu->active_lock);
> >
> > +     trace_dma_fence_emit(submit->hw_fence);
> >       gpu->funcs->submit(gpu, submit);
> >       gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
> >
>