[PATCH 2/4] drm/amdgpu/ttm: use multihop

[Christian König]

Am 09.11.20 um 01:54 schrieb Dave Airlie:
> From: Dave Airlie <airlied at redhat.com>
>
> This removes the code to move resources directly between
> SYSTEM and VRAM in favour of using the core ttm mulithop code.
>
> Signed-off-by: Dave Airlie <airlied at redhat.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 136 +++---------------------
>   1 file changed, 13 insertions(+), 123 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index ce0d82802333..e1458d575aa9 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -512,119 +512,6 @@ static int amdgpu_move_blit(struct ttm_buffer_object *bo,
>   	return r;
>   }
>   
> -/**
> - * amdgpu_move_vram_ram - Copy VRAM buffer to RAM buffer
> - *
> - * Called by amdgpu_bo_move().
> - */
> -static int amdgpu_move_vram_ram(struct ttm_buffer_object *bo, bool evict,
> -				struct ttm_operation_ctx *ctx,
> -				struct ttm_resource *new_mem)
> -{
> -	struct ttm_resource *old_mem = &bo->mem;
> -	struct ttm_resource tmp_mem;
> -	struct ttm_place placements;
> -	struct ttm_placement placement;
> -	int r;
> -
> -	/* create space/pages for new_mem in GTT space */
> -	tmp_mem = *new_mem;
> -	tmp_mem.mm_node = NULL;
> -	placement.num_placement = 1;
> -	placement.placement = &placements;
> -	placement.num_busy_placement = 1;
> -	placement.busy_placement = &placements;
> -	placements.fpfn = 0;
> -	placements.lpfn = 0;
> -	placements.mem_type = TTM_PL_TT;
> -	placements.flags = 0;
> -	r = ttm_bo_mem_space(bo, &placement, &tmp_mem, ctx);
> -	if (unlikely(r)) {
> -		pr_err("Failed to find GTT space for blit from VRAM\n");
> -		return r;
> -	}
> -
> -	r = ttm_tt_populate(bo->bdev, bo->ttm, ctx);
> -	if (unlikely(r))
> -		goto out_cleanup;
> -
> -	/* Bind the memory to the GTT space */
> -	r = amdgpu_ttm_backend_bind(bo->bdev, bo->ttm, &tmp_mem);
> -	if (unlikely(r)) {
> -		goto out_cleanup;
> -	}
> -
> -	/* blit VRAM to GTT */
> -	r = amdgpu_move_blit(bo, evict, &tmp_mem, old_mem);
> -	if (unlikely(r)) {
> -		goto out_cleanup;
> -	}
> -
> -	r = ttm_bo_wait_ctx(bo, ctx);
> -	if (unlikely(r))
> -		goto out_cleanup;
> -
> -	amdgpu_ttm_backend_unbind(bo->bdev, bo->ttm);
> -	ttm_resource_free(bo, &bo->mem);
> -	ttm_bo_assign_mem(bo, new_mem);
> -out_cleanup:
> -	ttm_resource_free(bo, &tmp_mem);
> -	return r;
> -}
> -
> -/**
> - * amdgpu_move_ram_vram - Copy buffer from RAM to VRAM
> - *
> - * Called by amdgpu_bo_move().
> - */
> -static int amdgpu_move_ram_vram(struct ttm_buffer_object *bo, bool evict,
> -				struct ttm_operation_ctx *ctx,
> -				struct ttm_resource *new_mem)
> -{
> -	struct ttm_resource *old_mem = &bo->mem;
> -	struct ttm_resource tmp_mem;
> -	struct ttm_placement placement;
> -	struct ttm_place placements;
> -	int r;
> -
> -	/* make space in GTT for old_mem buffer */
> -	tmp_mem = *new_mem;
> -	tmp_mem.mm_node = NULL;
> -	placement.num_placement = 1;
> -	placement.placement = &placements;
> -	placement.num_busy_placement = 1;
> -	placement.busy_placement = &placements;
> -	placements.fpfn = 0;
> -	placements.lpfn = 0;
> -	placements.mem_type = TTM_PL_TT;
> -	placements.flags = 0;
> -	r = ttm_bo_mem_space(bo, &placement, &tmp_mem, ctx);
> -	if (unlikely(r)) {
> -		pr_err("Failed to find GTT space for blit to VRAM\n");
> -		return r;
> -	}
> -
> -	/* move/bind old memory to GTT space */
> -	r = ttm_tt_populate(bo->bdev, bo->ttm, ctx);
> -	if (unlikely(r))
> -		return r;
> -
> -	r = amdgpu_ttm_backend_bind(bo->bdev, bo->ttm, &tmp_mem);
> -	if (unlikely(r)) {
> -		goto out_cleanup;
> -	}
> -
> -	ttm_bo_assign_mem(bo, &tmp_mem);
> -	/* copy to VRAM */
> -	r = amdgpu_move_blit(bo, evict, new_mem, old_mem);
> -	if (unlikely(r)) {
> -		goto out_cleanup;
> -	}
> -out_cleanup:
> -	ttm_resource_free(bo, &tmp_mem);
> -	return r;
> -}
> -
>   /**
>    * amdgpu_mem_visible - Check that memory can be accessed by ttm_bo_move_memcpy
>    *
> @@ -664,6 +551,17 @@ static int amdgpu_bo_move(struct ttm_buffer_object *bo, bool evict,
>   	struct ttm_resource *old_mem = &bo->mem;
>   	int r;
>   
> +	if ((old_mem->mem_type == TTM_PL_SYSTEM &&
> +	     new_mem->mem_type == TTM_PL_VRAM) ||
> +	    (old_mem->mem_type == TTM_PL_VRAM &&
> +	     new_mem->mem_type == TTM_PL_SYSTEM)) {
> +		hop->fpfn = 0;
> +		hop->lpfn = 0;
> +		hop->mem_type = TTM_PL_TT;
> +		hop->flags = 0;
> +		return -EMULTIHOP;
> +	}
> +
>   	if (new_mem->mem_type == TTM_PL_TT) {
>   		r = amdgpu_ttm_backend_bind(bo->bdev, bo->ttm, new_mem);
>   		if (r)
> @@ -717,16 +615,8 @@ static int amdgpu_bo_move(struct ttm_buffer_object *bo, bool evict,
>   		goto memcpy;
>   	}
>   
> -	if (old_mem->mem_type == TTM_PL_VRAM &&
> -	    new_mem->mem_type == TTM_PL_SYSTEM) {
> -		r = amdgpu_move_vram_ram(bo, evict, ctx, new_mem);
> -	} else if (old_mem->mem_type == TTM_PL_SYSTEM &&
> -		   new_mem->mem_type == TTM_PL_VRAM) {
> -		r = amdgpu_move_ram_vram(bo, evict, ctx, new_mem);
> -	} else {
> -		r = amdgpu_move_blit(bo, evict,
> -				     new_mem, old_mem);
> -	}
> +	r = amdgpu_move_blit(bo, evict,
> +			     new_mem, old_mem);

Only a nit pick, but that can now probably be on one line.

Apart from that great cleanup. With the nits fixed the whole series is 
Reviewed-by: Christian König <christian.koenig at amd.com>

Regards,
Christian.

>   
>   	if (r) {
>   memcpy: