Re: AMD graphics performance regression in 4.15 and later

From: Jean-Marc Valin
Date: Mon Apr 09 2018 - 11:17:53 EST


On 04/09/2018 05:42 AM, Christian KÃnig wrote:
> Backporting all the detection logic is to invasive, but you could just
> go into drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c and forcefull use the
> other code path.
>
> Just look out for "#ifdef CONFIG_SWIOTLB" checks and disable those.

Do you mean just taking the 4.15 code as is and replacing
"#ifdef CONFIG_SWIOTLB" with "#if 0" in
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c or are you talking about using a
different version of drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c ?

Jean-Marc