Re: [patch] [sched] bitmap cleanup, speedup, 2.5.3-pre5

[H. Peter Anvin]

Followup to:  <[e-mail]>
By author:    Ingo Molnar <[e-mail]>
In newsgroup: linux.dev.kernel
> 
> +static __inline__ unsigned long __ffs(unsigned long word)
> +{
> +	__asm__("bsfl %1,%0"
> +		:"=r" (word)
> +		:"r" (word));
>  	return word;
>  }
> 

Should typically be:

static __inline__ unsigned long __ffs(unsigned long word)
{
	__asm__("bsfl %1,%0"
		:"=r" (word)
		:"rm" (word));
 	return word;
 }

There is no reason to force the compiler to put the operand in a
register.

	-hpa
-- 
<[e-mail]> at work, <[e-mail]> in private!
"Unix gives you enough rope to shoot yourself in the foot."
http://www.zytor.com/~hpa/puzzle.txt	<[e-mail]>