[PATCH 2/2] drm/ttm: remove no_retry flag

[Daniel Vetter]

On Fri, Oct 2, 2020 at 1:31 PM Christian König
<ckoenig.leichtzumerken at gmail.com> wrote:
>
> Amdgpu was the only user of this.
>
> Signed-off-by: Christian König <christian.koenig at amd.com>

Uh this smells like a fishy band-aid. And the original commit
introducing this also doesn't sched any light on why this should
happen, and why it's specific to the amdgpu driver. Do you have some
more memories here?

I guess no retry makes sense for a "do you still have memory?" query,
but once we've commit to having that memory, I'm not seeing why we
should not try to find it? Might also tie into the lack of active
shrinking for ttm objects in the system domain.
-Daniel

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 6 +++---
>  drivers/gpu/drm/ttm/ttm_tt.c            | 3 ---
>  include/drm/ttm/ttm_device.h            | 2 --
>  3 files changed, 3 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index c5f2b4971ef7..0a4233985870 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -1298,6 +1298,9 @@ static struct ttm_tt *amdgpu_ttm_tt_create(struct ttm_buffer_object *bo,
>         }
>         gtt->gobj = &bo->base;
>
> +       /* We opt to avoid OOM on system pages allocations */
> +       page_flags |= TTM_PAGE_FLAG_NO_RETRY;
> +
>         if (dma_addressing_limited(adev->dev))
>                 page_flags |= TTM_PAGE_FLAG_DMA32;
>
> @@ -1895,9 +1898,6 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)
>         }
>         adev->mman.initialized = true;
>
> -       /* We opt to avoid OOM on system pages allocations */
> -       adev->mman.bdev.no_retry = true;
> -
>         /* Initialize VRAM pool with all of VRAM divided into pages */
>         r = amdgpu_vram_mgr_init(adev);
>         if (r) {
> diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
> index e2b1e6c53a04..98514abaa939 100644
> --- a/drivers/gpu/drm/ttm/ttm_tt.c
> +++ b/drivers/gpu/drm/ttm/ttm_tt.c
> @@ -52,9 +52,6 @@ int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
>         if (bo->ttm)
>                 return 0;
>
> -       if (bdev->no_retry)
> -               page_flags |= TTM_PAGE_FLAG_NO_RETRY;
> -
>         switch (bo->type) {
>         case ttm_bo_type_device:
>                 if (zero_alloc)
> diff --git a/include/drm/ttm/ttm_device.h b/include/drm/ttm/ttm_device.h
> index bfc6dd87f2d3..e0eba36c1309 100644
> --- a/include/drm/ttm/ttm_device.h
> +++ b/include/drm/ttm/ttm_device.h
> @@ -326,8 +326,6 @@ struct ttm_device {
>          */
>
>         struct delayed_work wq;
> -
> -       bool no_retry;
>  };
>
>  static inline struct ttm_resource_manager *
> --
> 2.17.1
>


-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch