Am 06.07.2017 um 12:51 schrieb Michel Dänzer:
> From: John Brooks <john at fastquake.com>
>
> When a BO is moved to VRAM, clear AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED.
> This allows it to potentially later move to invisible VRAM if the CPU
> does not access it again.
>
> Setting the CPU_ACCESS flag in amdgpu_bo_fault_reserve_notify() also means
> that we can remove the loop to restrict lpfn to the end of visible VRAM,
> because amdgpu_ttm_placement_init() will do it for us.
>
> v3 [Michel Dänzer]
> * Use AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED instead of a new flag
> (Christian König)
> * Explicitly mention amdgpu_bo_fault_reserve_notify in amdgpu_bo_move
>
> Suggested-by: Michel Dänzer <michel.daenzer at amd.com>
> Signed-off-by: John Brooks <john at fastquake.com>
> Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
Reviewed-by: Christian König <christian.koenig at amd.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 20 ++++++++++----------
> drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 9 +++++++++
> 2 files changed, 19 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> index e429829ae93d..93601fbea695 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> @@ -432,6 +432,10 @@ int amdgpu_bo_create_restricted(struct amdgpu_device *adev,
>
> trace_amdgpu_bo_create(bo);
>
> + /* Treat CPU_ACCESS_REQUIRED only as a hint if given by UMD */
> + if (type == ttm_bo_type_device)
> + bo->flags &= ~AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED;
> +
> return 0;
>
> fail_unreserve:
> @@ -945,13 +949,17 @@ int amdgpu_bo_fault_reserve_notify(struct ttm_buffer_object *bo)
> {
> struct amdgpu_device *adev = amdgpu_ttm_adev(bo->bdev);
> struct amdgpu_bo *abo;
> - unsigned long offset, size, lpfn;
> - int i, r;
> + unsigned long offset, size;
> + int r;
>
> if (!amdgpu_ttm_bo_is_amdgpu_bo(bo))
> return 0;
>
> abo = container_of(bo, struct amdgpu_bo, tbo);
> +
> + /* Remember that this BO was accessed by the CPU */
> + abo->flags |= AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED;
> +
> if (bo->mem.mem_type != TTM_PL_VRAM)
> return 0;
>
> @@ -967,14 +975,6 @@ int amdgpu_bo_fault_reserve_notify(struct ttm_buffer_object *bo)
> /* hurrah the memory is not visible ! */
> atomic64_inc(&adev->num_vram_cpu_page_faults);
> amdgpu_ttm_placement_from_domain(abo, AMDGPU_GEM_DOMAIN_VRAM);
> - lpfn = adev->mc.visible_vram_size >> PAGE_SHIFT;
> - for (i = 0; i < abo->placement.num_placement; i++) {
> - /* Force into visible VRAM */
> - if ((abo->placements[i].flags & TTM_PL_FLAG_VRAM) &&
> - (!abo->placements[i].lpfn ||
> - abo->placements[i].lpfn > lpfn))
> - abo->placements[i].lpfn = lpfn;
> - }
> r = ttm_bo_validate(bo, &abo->placement, false, false);
> if (unlikely(r == -ENOMEM)) {
> amdgpu_ttm_placement_from_domain(abo, AMDGPU_GEM_DOMAIN_GTT);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index 9d4861aea18a..58576375b91c 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -493,6 +493,15 @@ static int amdgpu_bo_move(struct ttm_buffer_object *bo,
> }
> }
>
> + if (bo->type == ttm_bo_type_device &&
> + new_mem->mem_type == TTM_PL_VRAM &&
> + old_mem->mem_type != TTM_PL_VRAM) {
> + /* amdgpu_bo_fault_reserve_notify will re-set this if the CPU
> + * accesses the BO after it's moved.
> + */
> + abo->flags &= ~AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED;
> + }
> +
> /* update statistics */
> atomic64_add((u64)bo->num_pages << PAGE_SHIFT, &adev->num_bytes_moved);
> return 0;
