Re: [PATCH] drm/radeon: drop ttm two ended allocation

["Christian König" <deathsimple@vodafone.de>]

On 17.03.2015 16:59, Alex Deucher wrote:
> radeon_bo_create() calls radeon_ttm_placement_from_domain()
> before ttm_bo_init() is called.  radeon_ttm_placement_from_domain()
> uses the ttm bo size to determine when to select top down
> allocation but since the ttm bo is not initialized yet the
> check is always false.  It only took affect when buffers
> were validated later.  It also seemed to regress suspend
> and resume on some systems possibly due to it not
> taking affect in radeon_bo_create().
>
> radeon_bo_create() and radeon_ttm_placement_from_domain()
> need to be reworked substantially for this to be optimally
> effective.  Re-enable it at that point.
>
> Noticed-by: Oded Gabbay <oded.gabbay@amd.com>
> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
> Cc: stable@vger.kernel.org

Reviewed-by: Christian König <christian.koenig@amd.com>

> ---
>   drivers/gpu/drm/radeon/radeon_object.c | 11 -----------
>   1 file changed, 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/radeon/radeon_object.c b/drivers/gpu/drm/radeon/radeon_object.c
> index 43e0994..318165d 100644
> --- a/drivers/gpu/drm/radeon/radeon_object.c
> +++ b/drivers/gpu/drm/radeon/radeon_object.c
> @@ -173,17 +173,6 @@ void radeon_ttm_placement_from_domain(struct radeon_bo *rbo, u32 domain)
>   		else
>   			rbo->placements[i].lpfn = 0;
>   	}
> -
> -	/*
> -	 * Use two-ended allocation depending on the buffer size to
> -	 * improve fragmentation quality.
> -	 * 512kb was measured as the most optimal number.
> -	 */
> -	if (rbo->tbo.mem.size > 512 * 1024) {
> -		for (i = 0; i < c; i++) {
> -			rbo->placements[i].flags |= TTM_PL_FLAG_TOPDOWN;
> -		}
> -	}
>   }
>   
>   int radeon_bo_create(struct radeon_device *rdev,