Re: [PATCH v2 2/2] xen: Introduce cmpxchg64() and guest_cmpxchg64()

[Julien Grall <julien@xxxxxxx>]

Hi Jan,

On 14/09/2020 09:48, Jan Beulich wrote:
> On 11.09.2020 18:06, Julien Grall wrote:
> > --- a/xen/include/asm-x86/guest_atomics.h
> > +++ b/xen/include/asm-x86/guest_atomics.h
> > @@ -20,6 +20,7 @@
> >       ((void)(d), test_and_change_bit(nr, p))
> >   
> >   #define guest_cmpxchg(d, ptr, o, n) ((void)(d), cmpxchg(ptr, o, n))
> > +#define guest_cmpxchg64(d, ptr, o, n) ((void)(d), cmpxchg(ptr, o, n))
> While them sitting side by side there's perhaps little risk of
> them going out of sync with one another, I still find it a
> little odd to open-code guest_cmpxchg() instead of using it,
It depends on how you view it... The implementation is indeed the same 
but they are meant to be used in different places.
Anyway... I can use:

#define guest_cmpxchg64 guest_cmpxchg

Cheers,

--
Julien Grall