[PATCH 1/2] drm//amdgpu: Add job fence to resv conditionally

[Pan, Xinhui]

wait, this causes test case in Sl+ state. need take a look.
 
> 2020年3月13日 19:53，Pan, Xinhui <Xinhui.Pan at amd.com> 写道：
> 
> If a job need sync the bo resv, it is likely that bo need the job fence
> to sync with others.
> 
> Cc: Christian König <christian.koenig at amd.com>
> Cc: Alex Deucher <alexander.deucher at amd.com>
> Cc: Felix Kuehling <Felix.Kuehling at amd.com>
> Suggested-by: Christian König <christian.koenig at amd.com>
> Signed-off-by: xinhui pan <xinhui.pan at amd.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h      | 5 +++++
> drivers/gpu/drm/amd/amdgpu/amdgpu_vm_sdma.c | 9 +++++++++
> 2 files changed, 14 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> index b5705fcfc935..ca6021b4200b 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> @@ -226,6 +226,11 @@ struct amdgpu_vm_update_params {
> 	 * @num_dw_left: number of dw left for the IB
> 	 */
> 	unsigned int num_dw_left;
> +
> +	/**
> +	 * @resv: sync the resv and add job fence to it conditionally.
> +	 */
> +	struct dma_resv *resv;
> };
> 
> struct amdgpu_vm_update_funcs {
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_sdma.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_sdma.c
> index 4cc7881f438c..0cfac59bff36 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_sdma.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_sdma.c
> @@ -70,6 +70,8 @@ static int amdgpu_vm_sdma_prepare(struct amdgpu_vm_update_params *p,
> 
> 	p->num_dw_left = ndw;
> 
> +	p->resv = resv;
> +
> 	if (!resv)
> 		return 0;
> 
> @@ -111,6 +113,13 @@ static int amdgpu_vm_sdma_commit(struct amdgpu_vm_update_params *p,
> 		swap(p->vm->last_delayed, tmp);
> 	dma_fence_put(tmp);
> 
> +	/* add job fence to resv.
> +	 * MM notifier path is an exception as we can not grab the
> +	 * resv lock.
> +	 */
> +	if (!p->direct && p->resv)
> +		dma_resv_add_shared_fence(p->resv, f);
> +
> 	if (fence && !p->direct)
> 		swap(*fence, f);
> 	dma_fence_put(f);
> -- 
> 2.17.1
>