Re: [PATCH 06/16] drm/amdgpu: use DMA_RESV_USAGE_KERNEL

[Daniel Vetter <daniel@ffwll.ch>]

On Wed, Apr 06, 2022 at 09:51:22AM +0200, Christian König wrote:
> Wait only for kernel fences before kmap or UVD direct submission.
> 
> This also makes sure that we always wait in amdgpu_bo_kmap() even when
> returning a cached pointer.
> 
> Signed-off-by: Christian König <christian.koenig@amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 10 +++++-----
>  drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c    |  2 +-
>  2 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> index a3cdf8a24377..5832c05ab10d 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> @@ -761,6 +761,11 @@ int amdgpu_bo_kmap(struct amdgpu_bo *bo, void **ptr)
>  	if (bo->flags & AMDGPU_GEM_CREATE_NO_CPU_ACCESS)
>  		return -EPERM;
>  
> +	r = dma_resv_wait_timeout(bo->tbo.base.resv, DMA_RESV_USAGE_KERNEL,
> +				  false, MAX_SCHEDULE_TIMEOUT);
> +	if (r < 0)
> +		return r;
> +
>  	kptr = amdgpu_bo_kptr(bo);
>  	if (kptr) {
>  		if (ptr)
> @@ -768,11 +773,6 @@ int amdgpu_bo_kmap(struct amdgpu_bo *bo, void **ptr)
>  		return 0;
>  	}
>  
> -	r = dma_resv_wait_timeout(bo->tbo.base.resv, DMA_RESV_USAGE_WRITE,
> -				  false, MAX_SCHEDULE_TIMEOUT);
> -	if (r < 0)
> -		return r;
> -
>  	r = ttm_bo_kmap(&bo->tbo, 0, bo->tbo.resource->num_pages, &bo->kmap);

I wonder whether waiting for kernel fences shouldn't be ttm's duty here.
Anyway patch makes some sense to me.

Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
>  	if (r)
>  		return r;
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c
> index 3654326219e0..6eac649499d3 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c
> @@ -1164,7 +1164,7 @@ static int amdgpu_uvd_send_msg(struct amdgpu_ring *ring, struct amdgpu_bo *bo,
>  
>  	if (direct) {
>  		r = dma_resv_wait_timeout(bo->tbo.base.resv,
> -					  DMA_RESV_USAGE_WRITE, false,
> +					  DMA_RESV_USAGE_KERNEL, false,
>  					  msecs_to_jiffies(10));
>  		if (r == 0)
>  			r = -ETIMEDOUT;
> -- 
> 2.25.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch