Re: [PATCH v2 5/6] drm/i915/ttm: switch over to ttm_buddy_man

[Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>]

On 6/8/21 10:44 AM, Matthew Auld wrote:
> Move back to the buddy allocator for managing device local memory, and
> restore the lost mock selftests. Keep around the range manager related
> bits, since we likely need this for managing stolen at some point. For
> stolen we also don't need to reserve anything so no need to support a
> generic reserve interface.
>
> v2(Thomas):
>      - bo->page_alignment is in page units, not bytes
>
> Signed-off-by: Matthew Auld <matthew.auld@xxxxxxxxx>
> Cc: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>
> Reviewed-by: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>
> ---
>   drivers/gpu/drm/i915/gem/i915_gem_ttm.c       |  26 +--
>   drivers/gpu/drm/i915/intel_memory_region.c    |  55 +-----
>   drivers/gpu/drm/i915/intel_memory_region.h    |  17 --
>   drivers/gpu/drm/i915/intel_region_ttm.c       | 100 +++--------
>   .../drm/i915/selftests/intel_memory_region.c  | 170 ++++++++++++------
>   drivers/gpu/drm/i915/selftests/mock_region.c  |  15 +-
>   6 files changed, 168 insertions(+), 215 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> index c612275c36c9..5bf1d1945dd6 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> @@ -181,11 +181,7 @@ static bool i915_ttm_eviction_valuable(struct ttm_buffer_object *bo,
>   	struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
>   
>   	/* Will do for now. Our pinned objects are still on TTM's LRU lists */
> -	if (!i915_gem_object_evictable(obj))
> -		return false;
> -
> -	/* This isn't valid with a buddy allocator */
> -	return ttm_bo_eviction_valuable(bo, place);
> +	return i915_gem_object_evictable(obj);
>   }
>   
>   static void i915_ttm_evict_flags(struct ttm_buffer_object *bo,
> @@ -328,11 +324,15 @@ i915_ttm_resource_get_st(struct drm_i915_gem_object *obj,
>   	struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
>   	struct ttm_resource_manager *man =
>   		ttm_manager_type(bo->bdev, res->mem_type);
> +	struct intel_memory_region *mr = obj->mm.region;
>   
>   	if (man->use_tt)
>   		return i915_ttm_tt_get_st(bo->ttm);
>   
> -	return intel_region_ttm_node_to_st(obj->mm.region, res->mm_node);
> +	if (mr->is_range_manager)

Did you look at moving this test into intel_region_ttm_node_to_st())

> +		return intel_region_ttm_node_to_st(mr, res);
> +	else
> +		return i915_sg_from_buddy_resource(res, mr->region.start);
>   }

Thanks,

Thomas