[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 at quicinc.com> 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 at quicinc.com> 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 at quicinc.com>
>>>> ---
>>>>
>>>> (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
>>>>