From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Niels de Vos <ndevos@redhat.com>
Cc: linux-omap@vger.kernel.org, linux-fbdev@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] omap2/omapfb: make DBG() more resistant in if-else constructions
Date: Tue, 10 May 2011 09:42:01 +0000 [thread overview]
Message-ID: <BANLkTinEJZ=fvJmWRkQ7kKyxbFRaJnum7g@mail.gmail.com> (raw)
In-Reply-To: <1305019249-9898-1-git-send-email-ndevos@redhat.com>
On Tue, May 10, 2011 at 11:20, Niels de Vos <ndevos@redhat.com> wrote:
> When DBG() is used in a simple if-else, the resulting code path
> currently depends on the definition of DBG(). Inserting the statement in
> a "do { ... } while (0)" prevents this possible misuse.
>
> Signed-off-by: Niels de Vos <ndevos@redhat.com>
> --- a/drivers/video/omap2/omapfb/omapfb.h
> +++ b/drivers/video/omap2/omapfb/omapfb.h
> @@ -34,8 +34,10 @@
> #ifdef DEBUG
> extern unsigned int omapfb_debug;
> #define DBG(format, ...) \
> - if (omapfb_debug) \
> - printk(KERN_DEBUG "OMAPFB: " format, ## __VA_ARGS__)
> + do { \
> + if (omapfb_debug) \
> + printk(KERN_DEBUG "OMAPFB: " format, ## __VA_ARGS__); \
> + while (0)
Where's the closing '}'?
> #else
> #define DBG(format, ...)
BTW, no printf()-style format checking here.
> #endif
What about using the standard pr_debug()/dev_dbg() instead?
With dynamic debug, it can be enabled at run time.
As a bonus, you get printf()-style format checking if debugging is disabled.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
next prev parent reply other threads:[~2011-05-10 9:42 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-10 9:20 [PATCH] omap2/omapfb: make DBG() more resistant in if-else constructions Niels de Vos
2011-05-10 9:42 ` Geert Uytterhoeven [this message]
2011-05-10 10:57 ` Niels de Vos
2011-05-10 11:07 ` [PATCH V2] " Niels de Vos
2011-05-10 12:16 ` [PATCH V2] omap2/omapfb: make DBG() more resistant in if-else Tomi Valkeinen
2011-05-10 12:08 ` [PATCH] " Tomi Valkeinen
2011-05-10 12:14 ` [PATCH] omap2/omapfb: make DBG() more resistant in if-else constructions Geert Uytterhoeven
2011-05-10 9:49 ` [PATCH] omap2/omapfb: make DBG() more resistant in if-else Premi, Sanjeev
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