Re: Linux 2.6.32-rc1

Linus Torvalds
2009-09-30T20:21:48Z

On Wed, 30 Sep 2009, Eric Dumazet wrote:
> > +#define cmpxchg64(ptr, o, n) \
> > +({ \
> > + __typeof__(*(ptr)) __ret; \
> > + __typeof__(*(ptr)) __old = (o); \
> > + __typeof__(*(ptr)) __new = (n); \
> > + alternative_io("call cmpxchg8b_emu", \
> > + "lock; cmpxchg8b (%%esi)" , \
> > + X86_FEATURE_CX8, \
> > + "=A" (__ret), \
> > + "S" ((ptr)), "0" (__old), \
> > + "b" ((unsigned int)__new), \
> > + "c" ((unsigned int)(__new>>32))); \
>
> probably a "memory" clobber is needed, alternative_io() doesnt provide it.

Yeah, good catch.

Linus