[PATCH 1/5] drm/amdgpu: rework queue reset scheduler interaction

[Rodrigo Siqueira]

On 05/02, Christian König wrote:
> Stopping the scheduler for queue reset is generally a good idea because
> it prevents any worker from touching the ring buffer.
> 
> But using amdgpu_fence_driver_force_completion() before restarting it was
> a really bad idea because it marked fences as failed while the work was
> potentially still running.
> 
> Stop doing that and cleanup the comment a bit.
> 
> Signed-off-by: Christian König <christian.koenig at amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_job.c | 27 ++++++++++++-------------
>  1 file changed, 13 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
> index acb21fc8b3ce..a0fab947143b 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
> @@ -136,10 +136,12 @@ static enum drm_gpu_sched_stat amdgpu_job_timedout(struct drm_sched_job *s_job)
>  	} else if (amdgpu_gpu_recovery && ring->funcs->reset) {
>  		bool is_guilty;
>  
> -		dev_err(adev->dev, "Starting %s ring reset\n", s_job->sched->name);
> -		/* stop the scheduler, but don't mess with the
> -		 * bad job yet because if ring reset fails
> -		 * we'll fall back to full GPU reset.
> +		dev_err(adev->dev, "Starting %s ring reset\n",
> +			s_job->sched->name);
> +
> +		/*
> +		 * Stop the scheduler to prevent anybody else from touching the
> +		 * ring buffer.
>  		 */
>  		drm_sched_wqueue_stop(&ring->sched);
>  
> @@ -157,19 +159,16 @@ static enum drm_gpu_sched_stat amdgpu_job_timedout(struct drm_sched_job *s_job)
>  
>  		r = amdgpu_ring_reset(ring, job->vmid);
>  		if (!r) {
> -			if (amdgpu_ring_sched_ready(ring))
> -				drm_sched_stop(&ring->sched, s_job);
> -			if (is_guilty) {
> +			if (is_guilty)
>  				atomic_inc(&ring->adev->gpu_reset_counter);
> -				amdgpu_fence_driver_force_completion(ring);
> -			}
> -			if (amdgpu_ring_sched_ready(ring))
> -				drm_sched_start(&ring->sched, 0);
> -			dev_err(adev->dev, "Ring %s reset succeeded\n", ring->sched.name);
> -			drm_dev_wedged_event(adev_to_drm(adev), DRM_WEDGE_RECOVERY_NONE);
> +			drm_sched_wqueue_start(&ring->sched);
> +			dev_err(adev->dev, "Ring %s reset succeeded\n",
> +				ring->sched.name);
> +			drm_dev_wedged_event(adev_to_drm(adev),
> +					     DRM_WEDGE_RECOVERY_NONE);
>  			goto exit;
>  		}
> -		dev_err(adev->dev, "Ring %s reset failure\n", ring->sched.name);
> +		dev_err(adev->dev, "Ring %s reset failed\n", ring->sched.name);
>  	}
>  	dma_fence_set_error(&s_job->s_fence->finished, -ETIME);
>  
> -- 
> 2.34.1
>

Hi Christian,

I tested your series with Polaris and the 6600 series with the HangTest
suite, and with your series, the following tests failed:

 - soft_recovery_loop
 - soft_recovery_pagefault_read
 - soft_recovery_pagefault_write

When using the latest code of the amd-staging-drm-next, all of the above
tests behave well. I'll try to identify what is going on.

Thanks

-- 
Rodrigo Siqueira