Re: [bisected] kernel panic 2.6.22 -> 2.6.26-rc9+

[Krzysztof Halasa]

Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> writes:

> --- a/include/asm-arm/bitops.h~a
> +++ a/include/asm-arm/bitops.h
> @@ -277,9 +277,16 @@ static inline int constant_fls(int x)
>   * the clz instruction for much better code efficiency.
>   */
>  
> -#define fls(x) \
> +#define __fls(x) \
>  	( __builtin_constant_p(x) ? constant_fls(x) : \
>  	  ({ int __r; asm("clz\t%0, %1" : "=r"(__r) : "r"(x) : "cc"); 32-__r; }) )
> +
> +/* Implement fls() in C so that 64-bit args are suitably truncated */
> +static inline int fls(int x)
> +{
> +	return __fls(x);
> +}
> +

Well, I like it more as it fixes all possible places instead of only
fls64().

But... can't we just move the #define body into the inline fls(x)?
Will there be other users of __fls(x)? It seems the
__builtin_constant_p(x) works for inline functions.

The above patch fixes the kernel panic, too.
-- 
Krzysztof Halasa
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/