linux-kernel - Re: [PATCH v3] drm/ttm: Delete an unnecessary check before the function call "ttm_tt

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Date:	Mon, 18 Jul 2016 16:45:13 +0200
From:	Daniel Vetter <daniel@...ll.ch>
To:	SF Markus Elfring <elfring@...rs.sourceforge.net>
Cc:	dri-devel@...ts.freedesktop.org, Daniel Vetter <daniel@...ll.ch>,
	David Airlie <airlied@...ux.ie>,
	LKML <linux-kernel@...r.kernel.org>,
	kernel-janitors@...r.kernel.org,
	Julia Lawall <julia.lawall@...6.fr>
Subject: Re: [PATCH v3] drm/ttm: Delete an unnecessary check before the
 function call "ttm_tt_destroy"

On Mon, Jul 18, 2016 at 04:10:36PM +0200, SF Markus Elfring wrote:
> From: Markus Elfring <elfring@...rs.sourceforge.net>
> Date: Mon, 18 Jul 2016 16:06:18 +0200
> 
> The ttm_tt_destroy() function tests whether its argument is NULL
> and then returns immediately. Thus the test around the call is not needed.
> 
> This issue was detected by using the Coccinelle software.
> 
> Signed-off-by: Markus Elfring <elfring@...rs.sourceforge.net>

When resending pls describe what changed (and why). Also I'd still like
that smatch included in the commit message.
-Daniel

> ---
>  drivers/gpu/drm/ttm/ttm_bo.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
> index 39386f5..4e55863 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo.c
> @@ -146,9 +146,7 @@ static void ttm_bo_release_list(struct kref *list_kref)
>  	BUG_ON(bo->mem.mm_node != NULL);
>  	BUG_ON(!list_empty(&bo->lru));
>  	BUG_ON(!list_empty(&bo->ddestroy));
> -
> -	if (bo->ttm)
> -		ttm_tt_destroy(bo->ttm);
> +	ttm_tt_destroy(bo->ttm);
>  	atomic_dec(&bo->glob->bo_count);
>  	if (bo->resv == &bo->ttm_resv)
>  		reservation_object_fini(&bo->ttm_resv);
> -- 
> 2.9.2
> 

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