linux-kernel - Re: [PATCH] drm/atomic: Delete an unnecessary check before drm_property_unreference_blob()

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Message-ID: <CAOw6vb+o++yMWomtq59b+ATFjgtg9J55xXS5L=h_1RA3sQGnFg@mail.gmail.com>
Date:	Wed, 20 Jul 2016 13:29:33 -0400
From:	Sean Paul <seanpaul@...omium.org>
To:	SF Markus Elfring <elfring@...rs.sourceforge.net>
Cc:	dri-devel <dri-devel@...ts.freedesktop.org>,
	Daniel Vetter <daniel@...ll.ch>,
	David Airlie <airlied@...ux.ie>,
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
	Julia Lawall <julia.lawall@...6.fr>,
	kernel-janitors@...r.kernel.org,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] drm/atomic: Delete an unnecessary check before drm_property_unreference_blob()

On Wed, Jul 20, 2016 at 12:02 PM, SF Markus Elfring
<elfring@...rs.sourceforge.net> wrote:
> From: Markus Elfring <elfring@...rs.sourceforge.net>
> Date: Wed, 20 Jul 2016 17:54:32 +0200
>
> The drm_property_unreference_blob() 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>
> ---
>  drivers/gpu/drm/drm_atomic.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> index 3cee084..8d2f111 100644
> --- a/drivers/gpu/drm/drm_atomic.c
> +++ b/drivers/gpu/drm/drm_atomic.c
> @@ -404,8 +404,7 @@ drm_atomic_replace_property_blob(struct drm_property_blob **blob,
>         if (old_blob == new_blob)
>                 return;
>
> -       if (old_blob)
> -               drm_property_unreference_blob(old_blob);
> +       drm_property_unreference_blob(old_blob);
>         if (new_blob)
>                 drm_property_reference_blob(new_blob);

I wonder whether it'd be worthwhile to add the same check to
drm_property_reference_blob to make things symmetric.

Musings aside, I've applied this to drm-misc.

Sean

>         *blob = new_blob;
> --
> 2.9.2
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@...ts.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

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