Re: [PATCH v2 4/7] drm/amdgpu: Add suspend function to clear the GPU power profile.

["Yadav, Arvind" <arvyadav@xxxxxxx>]

On 8/22/2023 6:24 PM, Lazar, Lijo wrote:
> On 8/22/2023 5:52 PM, Yadav, Arvind wrote:
> > On 8/22/2023 12:01 PM, Lazar, Lijo wrote:
> > > On 8/21/2023 12:17 PM, Arvind Yadav wrote:
> > > > This patch adds a suspend function that will clear the GPU
> > > > power profile before going into suspend state.
> > > >
> > > > v2:
> > > > - Add the new suspend function based on review comment.
> > > >
> > > > Cc: Shashank Sharma <shashank.sharma@xxxxxxx>
> > > > Cc: Christian Koenig <christian.koenig@xxxxxxx>
> > > > Cc: Alex Deucher <alexander.deucher@xxxxxxx>
> > > > Signed-off-by: Arvind Yadav <Arvind.Yadav@xxxxxxx>
> > > > ---
> > > >   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c    |  2 ++
> > > >   drivers/gpu/drm/amd/amdgpu/amdgpu_workload.c  | 23 
> > > > +++++++++++++++++++
> > > >   drivers/gpu/drm/amd/include/amdgpu_workload.h |  2 ++
> > > >   3 files changed, 27 insertions(+)
> > > >
> > > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c 
> > > > b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> > > > index cd3bf641b630..3b70e657b439 100644
> > > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> > > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> > > > @@ -4212,6 +4212,8 @@ int amdgpu_device_suspend(struct drm_device 
> > > > *dev, bool fbcon)
> > > >         amdgpu_ras_suspend(adev);
> > > >   +    amdgpu_workload_profile_suspend(adev);
> > > > +
> > > >       amdgpu_device_ip_suspend_phase1(adev);
> > > >         if (!adev->in_s0ix)
> > > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_workload.c 
> > > > b/drivers/gpu/drm/amd/amdgpu/amdgpu_workload.c
> > > > index 6367eb88a44d..44ca8e986984 100644
> > > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_workload.c
> > > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_workload.c
> > > > @@ -174,6 +174,29 @@ void amdgpu_workload_profile_set(struct 
> > > > amdgpu_device *adev,
> > > >       mutex_unlock(&workload->workload_lock);
> > > >   }
> > > >   +void amdgpu_workload_profile_suspend(struct amdgpu_device *adev)
> > > > +{
> > > > +    struct amdgpu_smu_workload *workload = &adev->smu_workload;
> > > > +    int ret;
> > > > +
> > > > +    mutex_lock(&workload->workload_lock);
> > > > + cancel_delayed_work_sync(&workload->smu_delayed_work);
> > >
> > > Another deadlock candidate. Between fini() and suspend(), the only 
> > > difference probably could be initialization status. If so, just use 
> > > a helper that is used during fini() and suspend().
> > Before going to suspend(), we need to cancel the work and clear all 
> > the profiles but in fini() we are destroying the mutex. also it will 
> > be called when we are unloading everything.
>
> What I meant is for both suspend/fini, you need to cancel any work 
> scheduled, clear refcounts and set the profile back to default 
> profile. Keep this in a helper and reuse.
Noted.

Thank you,
~Arvind

> Thanks,
> Lijo
>
> > ~Arvind
> >
> > > Thanks,
> > > Lijo
> > >
> > > > +
> > > > +    /* Clear all the set GPU power profile*/
> > > > +    for (int index = fls(workload->submit_workload_status);
> > > > +         index > 0; index--) {
> > > > +        if (workload->submit_workload_status & (1 << index)) {
> > > > + atomic_set(&workload->power_profile_ref[index], 0);
> > > > +            ret = amdgpu_power_profile_clear(adev, index);
> > > > +            if (ret)
> > > > +                DRM_WARN("Failed to clear power profile %s, err = 
> > > > %d\n",
> > > > +                     amdgpu_workload_mode_name[index], ret);
> > > > +        }
> > > > +    }
> > > > +    workload->submit_workload_status = 0;
> > > > +    mutex_unlock(&workload->workload_lock);
> > > > +}
> > > > +
> > > >   void amdgpu_workload_profile_init(struct amdgpu_device *adev)
> > > >   {
> > > >       adev->smu_workload.adev = adev;
> > > > diff --git a/drivers/gpu/drm/amd/include/amdgpu_workload.h 
> > > > b/drivers/gpu/drm/amd/include/amdgpu_workload.h
> > > > index ee1f87257f2d..0acd8769ec52 100644
> > > > --- a/drivers/gpu/drm/amd/include/amdgpu_workload.h
> > > > +++ b/drivers/gpu/drm/amd/include/amdgpu_workload.h
> > > > @@ -52,6 +52,8 @@ void amdgpu_workload_profile_put(struct 
> > > > amdgpu_device *adev,
> > > >   void amdgpu_workload_profile_set(struct amdgpu_device *adev,
> > > >                    uint32_t ring_type);
> > > >   +void amdgpu_workload_profile_suspend(struct amdgpu_device *adev);
> > > > +
> > > >   void amdgpu_workload_profile_init(struct amdgpu_device *adev);
> > > >     void amdgpu_workload_profile_fini(struct amdgpu_device *adev);