Am 30.06.2017 um 17:18 schrieb John Brooks:
> When a BO is moved to VRAM, clear AMDGPU_BO_FLAG_CPU_ACCESS. 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_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.
>
> Signed-off-by: John Brooks <john at fastquake.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 3 +++
> drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 8 ++++++++
> 2 files changed, 11 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> index fa8aeca..19bd2fd 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> @@ -953,6 +953,9 @@ int amdgpu_bo_fault_reserve_notify(struct ttm_buffer_object *bo)
> return 0;
>
> abo = container_of(bo, struct amdgpu_bo, tbo);
> +
> + abo->flags |= AMDGPU_BO_FLAG_CPU_ACCESS;
> +
> if (bo->mem.mem_type != TTM_PL_VRAM)
> return 0;
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index c9b131b..cc65cdd 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -417,6 +417,7 @@ static int amdgpu_move_ram_vram(struct ttm_buffer_object *bo,
> struct ttm_mem_reg *new_mem)
> {
> struct amdgpu_device *adev;
> + struct amdgpu_bo *abo;
> struct ttm_mem_reg *old_mem = &bo->mem;
> struct ttm_mem_reg tmp_mem;
> struct ttm_placement placement;
> @@ -424,6 +425,7 @@ static int amdgpu_move_ram_vram(struct ttm_buffer_object *bo,
> int r;
>
> adev = amdgpu_ttm_adev(bo->bdev);
> + abo = container_of(bo, struct amdgpu_bo, tbo);
> tmp_mem = *new_mem;
> tmp_mem.mm_node = NULL;
> placement.num_placement = 1;
> @@ -446,6 +448,12 @@ static int amdgpu_move_ram_vram(struct ttm_buffer_object *bo,
> if (unlikely(r)) {
> goto out_cleanup;
> }
> +
> + /* The page fault handler will re-set this if the CPU accesses the BO
> + * after it's moved.
> + */
> + abo->flags &= ~AMDGPU_BO_FLAG_CPU_ACCESS;
> +
This is the wrong place for clearing the flag. This code path is only
called when we move things back in after suspend/resume (or run out of
GTT space).
Regards,
Christian.
> out_cleanup:
> ttm_bo_mem_put(bo, &tmp_mem);
> return r;
