Re: [PATCH v3 2/8] drm/msm: Take single rpm refcount on behalf of all submits

[Akhil P Oommen]

On 8/1/2022 3:45 AM, Rob Clark wrote:
> On Sun, Jul 31, 2022 at 9:33 AM Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx> wrote:
> > On 7/31/2022 9:26 PM, Rob Clark wrote:
> > > On Sat, Jul 30, 2022 at 2:41 AM Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx> wrote:
> > > > Instead of separate refcount for each submit, take single rpm refcount
> > > > on behalf of all the submits. This makes it easier to drop the rpm
> > > > refcount during recovery in an upcoming patch.
> > > >
> > > > Signed-off-by: Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx>
> > > > ---
> > > >
> > > > (no changes since v1)
> > > I see no earlier version of this patch?
My bad, that is incorrect. This is a new patch included in the current 
series.

-Akhil.
> > > >    drivers/gpu/drm/msm/msm_gpu.c | 12 ++++++++----
> > > >    1 file changed, 8 insertions(+), 4 deletions(-)
> > > >
> > > > diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> > > > index c8cd9bf..e1dd3cc 100644
> > > > --- a/drivers/gpu/drm/msm/msm_gpu.c
> > > > +++ b/drivers/gpu/drm/msm/msm_gpu.c
> > > > @@ -663,11 +663,12 @@ static void retire_submit(struct msm_gpu *gpu, struct msm_ringbuffer *ring,
> > > >           mutex_lock(&gpu->active_lock);
> > > >           gpu->active_submits--;
> > > >           WARN_ON(gpu->active_submits < 0);
> > > > -       if (!gpu->active_submits)
> > > > +       if (!gpu->active_submits) {
> > > >                   msm_devfreq_idle(gpu);
> > > > -       mutex_unlock(&gpu->active_lock);
> > > > +               pm_runtime_put_autosuspend(&gpu->pdev->dev);
> > > > +       }
> > > >
> > > > -       pm_runtime_put_autosuspend(&gpu->pdev->dev);
> > > > +       mutex_unlock(&gpu->active_lock);
> > > >
> > > >           msm_gem_submit_put(submit);
> > > >    }
> > > > @@ -756,14 +757,17 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
> > > >
> > > >           /* Update devfreq on transition from idle->active: */
> > > >           mutex_lock(&gpu->active_lock);
> > > > -       if (!gpu->active_submits)
> > > > +       if (!gpu->active_submits) {
> > > > +               pm_runtime_get(&gpu->pdev->dev);
> > > >                   msm_devfreq_active(gpu);
> > > > +       }
> > > >           gpu->active_submits++;
> > > >           mutex_unlock(&gpu->active_lock);
> > > >
> > > >           gpu->funcs->submit(gpu, submit);
> > > >           gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
> > > >
> > > > +       pm_runtime_put(&gpu->pdev->dev);
> > > this looks unbalanced?
> > There is another pm_runtime_get_sync at the top of this function. Just
> > before hw_init().
> > https://elixir.bootlin.com/linux/v5.19-rc8/source/drivers/gpu/drm/msm/msm_gpu.c#L737
> oh, right.. sorry, I was looking at my local stack of WIP patches
> which went the opposite direction and moved the runpm into just
> msm_job_run().. I'll drop that one
>
> BR,
> -R
>
> > -Akhil.
> > > BR,
> > > -R
> > >
> > > >           hangcheck_timer_reset(gpu);
> > > >    }
> > > >
> > > > --
> > > > 2.7.4