[PATCH] drm/ttm: partial revert "cleanup ttm_tt_(unbind|destroy)"

[Felix Kuehling]

This patch introduces a compile warning:

/home/fkuehlin/compute/kernel/drivers/gpu/drm/ttm/ttm_tt.c: In function ‘ttm_tt_destroy’:
/home/fkuehlin/compute/kernel/drivers/gpu/drm/ttm/ttm_tt.c:169:6: warning: unused variable ‘ret’ [-Wunused-variable]
  int ret;
      ^

Regards,
  Felix

On 16-07-21 06:34 AM, Christian König wrote:
> From: Christian König <christian.koenig at amd.com>
>
> We still need to unbind explicitely during a move.
>
> This partial reverts commit ff20caa0bcbfef9f7686f8d1868a3b990921afd6.
>
> Signed-off-by: Christian König <christian.koenig at amd.com>
> ---
>  drivers/gpu/drm/ttm/ttm_bo_util.c |  1 +
>  drivers/gpu/drm/ttm/ttm_tt.c      | 15 ++++++++++++---
>  include/drm/ttm/ttm_bo_driver.h   |  9 +++++++++
>  3 files changed, 22 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
> index 0c389a5..6c412c3 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo_util.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
> @@ -53,6 +53,7 @@ int ttm_bo_move_ttm(struct ttm_buffer_object *bo,
>  	int ret;
>  
>  	if (old_mem->mem_type != TTM_PL_SYSTEM) {
> +		ttm_tt_unbind(ttm);
>  		ttm_bo_free_old_node(bo);
>  		ttm_flag_masked(&old_mem->placement, TTM_PL_FLAG_SYSTEM,
>  				TTM_PL_MASK_MEM);
> diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
> index d28d4333..fa42dc3 100644
> --- a/drivers/gpu/drm/ttm/ttm_tt.c
> +++ b/drivers/gpu/drm/ttm/ttm_tt.c
> @@ -172,9 +172,7 @@ void ttm_tt_destroy(struct ttm_tt *ttm)
>  		return;
>  
>  	if (ttm->state == tt_bound) {
> -		ret = ttm->func->unbind(ttm);
> -		BUG_ON(ret);
> -		ttm->state = tt_unbound;
> +		ttm_tt_unbind(ttm);
>  	}
>  
>  	if (ttm->state == tt_unbound)
> @@ -255,6 +253,17 @@ void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
>  }
>  EXPORT_SYMBOL(ttm_dma_tt_fini);
>  
> +void ttm_tt_unbind(struct ttm_tt *ttm)
> +{
> +	int ret;
> +
> +	if (ttm->state == tt_bound) {
> +		ret = ttm->func->unbind(ttm);
> +		BUG_ON(ret);
> +		ttm->state = tt_unbound;
> +	}
> +}
> +
>  int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
>  {
>  	int ret = 0;
> diff --git a/include/drm/ttm/ttm_bo_driver.h b/include/drm/ttm/ttm_bo_driver.h
> index 141cefb..e7d81a8 100644
> --- a/include/drm/ttm/ttm_bo_driver.h
> +++ b/include/drm/ttm/ttm_bo_driver.h
> @@ -628,6 +628,15 @@ extern int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem);
>  extern void ttm_tt_destroy(struct ttm_tt *ttm);
>  
>  /**
> + * ttm_ttm_unbind:
> + *
> + * @ttm: The struct ttm_tt.
> + *
> + * Unbind a struct ttm_tt.
> + */
> +extern void ttm_tt_unbind(struct ttm_tt *ttm);
> +
> +/**
>   * ttm_tt_swapin:
>   *
>   * @ttm: The struct ttm_tt.