[PATCH 5/7] drm/i915/gem/ttm: Respect the objection region in placement_from_obj

[Matthew Auld]

On Thu, 15 Jul 2021 at 23:39, Jason Ekstrand <jason at jlekstrand.net> wrote:
>
> Whenever we had a user object (n_placements > 0), we were ignoring
> obj->mm.region and always putting obj->placements[0] as the requested
> region.  For LMEM+SMEM objects, this was causing them to get shoved into
> LMEM on every i915_ttm_get_pages() even when SMEM was requested by, say,
> i915_gem_object_migrate().

i915_ttm_migrate calls i915_ttm_place_from_region() directly with the
requested region, so there shouldn't be an issue with migration right?
Do you have some more details?

>
> Signed-off-by: Jason Ekstrand <jason at jlekstrand.net>
> Cc: Thomas Hellström <thomas.hellstrom at linux.intel.com>
> Cc: Matthew Auld <matthew.auld at intel.com>
> Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> index d30f274c329c7..5985e994d56cf 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> @@ -150,8 +150,7 @@ i915_ttm_placement_from_obj(const struct drm_i915_gem_object *obj,
>         unsigned int i;
>
>         placement->num_placement = 1;
> -       i915_ttm_place_from_region(num_allowed ? obj->mm.placements[0] :
> -                                  obj->mm.region, requested, flags);
> +       i915_ttm_place_from_region(obj->mm.region, requested, flags);
>
>         /* Cache this on object? */
>         placement->num_busy_placement = num_allowed;
> --
> 2.31.1
>