Re: [PATCH REGRESSION] Revert "drm/amdgpu: stop scheduler when calling hw_fini (v2)"

["Christian König" <christian.koenig@amd.com>]

Am 10.01.22 um 17:08 schrieb Deucher, Alexander:
> [Public]
>
>> -----Original Message-----
>> From: Len Brown <lenb417@gmail.com> On Behalf Of Len Brown
>> Sent: Sunday, January 9, 2022 1:12 PM
>> To: torvalds@linux-foundation.org
>> Cc: linux-pm@vger.kernel.org; linux-kernel@vger.kernel.org; Len Brown
>> <len.brown@intel.com>; Chen, Guchun <Guchun.Chen@amd.com>;
>> Grodzovsky, Andrey <Andrey.Grodzovsky@amd.com>; Koenig, Christian
>> <Christian.Koenig@amd.com>; Deucher, Alexander
>> <Alexander.Deucher@amd.com>; stable@vger.kernel.org
>> Subject: [PATCH REGRESSION] Revert "drm/amdgpu: stop scheduler when
>> calling hw_fini (v2)"
>>
>> From: Len Brown <len.brown@intel.com>
>>
>> This reverts commit f7d6779df642720e22bffd449e683bb8690bd3bf.
>>
>> This bisected regression has impacted suspend-resume stability since 5.15-
>> rc1. It regressed -stable via 5.14.10.
>>
>> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbugz
>> illa.kernel.org%2Fshow_bug.cgi%3Fid%3D215315&amp;data=04%7C01%7Cal
>> exander.deucher%40amd.com%7Ccf790be4827f4df9f2d808d9d39b81af%7C3
>> dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637773487569442716%7C
>> Unknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJB
>> TiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&amp;sdata=AX0TXkyoMhy%2BZqE
>> VgRSWMkKd5nPa4WOv%2B1FZHLSErSw%3D&amp;reserved=0
>>
>> Fixes: f7d6779df64 ("drm/amdgpu: stop scheduler when calling hw_fini (v2)")
>> Cc: Guchun Chen <guchun.chen@amd.com>
>> Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
>> Cc: Christian Koenig <christian.koenig@amd.com>
>> Cc: Alex Deucher <alexander.deucher@amd.com>
>> Cc: <stable@vger.kernel.org> # 5.14+
>> Signed-off-by: Len Brown <len.brown@intel.com>
> @Chen, Guchun, @Grodzovsky, Andrey, @Koenig, Christian
>
> Any ideas?  What's the consequence of reverting this patch?  Didn't this patch fix another suspend/resume issue?

I think Guchun was just trying to adapt that we removed the scheduler 
stop from the fence driver hw fini path.

Not sure if that actually fixed something or was just a precaution.

Regards,
Christian.

>
> Alex
>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 8 --------
>>   1 file changed, 8 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
>> index 9afd11ca2709..45977a72b5dd 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
>> @@ -547,9 +547,6 @@ void amdgpu_fence_driver_hw_fini(struct
>> amdgpu_device *adev)
>>   		if (!ring || !ring->fence_drv.initialized)
>>   			continue;
>>
>> -		if (!ring->no_scheduler)
>> -			drm_sched_stop(&ring->sched, NULL);
>> -
>>   		/* You can't wait for HW to signal if it's gone */
>>   		if (!drm_dev_is_unplugged(adev_to_drm(adev)))
>>   			r = amdgpu_fence_wait_empty(ring);
>> @@ -609,11 +606,6 @@ void amdgpu_fence_driver_hw_init(struct
>> amdgpu_device *adev)
>>   		if (!ring || !ring->fence_drv.initialized)
>>   			continue;
>>
>> -		if (!ring->no_scheduler) {
>> -			drm_sched_resubmit_jobs(&ring->sched);
>> -			drm_sched_start(&ring->sched, true);
>> -		}
>> -
>>   		/* enable the interrupt */
>>   		if (ring->fence_drv.irq_src)
>>   			amdgpu_irq_get(adev, ring->fence_drv.irq_src,
>> --
>> 2.25.1