Re: [patch 1/5] Introduce __WARN()

[Richard Knutsson <ricknu-0@student.ltu.se>]

Arjan van de Ven wrote:
> From: Olof Johansson <olof@lixom.net>
>
> Introduce __WARN() in the generic case, so the generic WARN_ON()
> can use arch-specific code for when the condition is true.
>
> Signed-off-by: Olof Johansson <olof@lixom.net>
> Cc: <linux-arch@vger.kernel.org>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> ---
>
>  include/asm-generic/bug.h |   17 +++++++++++------
>  1 file changed, 11 insertions(+), 6 deletions(-)
>
> Index: linux-2.6.24-rc6/include/asm-generic/bug.h
> ===================================================================
> --- linux-2.6.24-rc6.orig/include/asm-generic/bug.h
> +++ linux-2.6.24-rc6/include/asm-generic/bug.h
> @@ -31,14 +31,19 @@ struct bug_entry {
>  #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while(0)
>  #endif
>  
> -#ifndef HAVE_ARCH_WARN_ON
> +#ifndef __WARN
> +#define __WARN() do {							\
> +	printk("WARNING: at %s:%d %s()\n", __FILE__,			\
> +		__LINE__, __FUNCTION__);				\
> +	dump_stack();							\
> +} while (0)
> +#endif
> +
> +#ifndef WARN_ON
>  #define WARN_ON(condition) ({						\
>  	int __ret_warn_on = !!(condition);				\
>   
What about using a boolean for __ret_warn_on, which then let us remove 
the '!!'?
(btw, wouldn't 'var != 0' actually be the proper semantic instead of 
playing with '!'s?)
> -	if (unlikely(__ret_warn_on)) {					\
> -		printk("WARNING: at %s:%d %s()\n", __FILE__,		\
> -			__LINE__, __FUNCTION__);			\
> -		dump_stack();						\
> -	}								\
> +	if (unlikely(__ret_warn_on))					\
> +		__WARN();						\
>  	unlikely(__ret_warn_on);					\
>  })
>  #endif
>
>