On Wed, Feb 22, 2017 at 12:27:37PM +0100, Peter Zijlstra wrote:
> On Wed, Feb 22, 2017 at 04:11:38AM +0900, Stafford Horne wrote:
> > +#define atomic_add_return atomic_add_return
> > +#define atomic_sub_return atomic_sub_return
> > +#define atomic_fetch_add atomic_fetch_add
> > +#define atomic_fetch_sub atomic_fetch_sub
> > +#define atomic_fetch_and atomic_fetch_and
> > +#define atomic_fetch_or atomic_fetch_or
> > +#define atomic_fetch_xor atomic_fetch_xor
> > +#define atomic_and atomic_and
> > +#define atomic_or atomic_or
> > +#define atomic_xor atomic_xor
> > +
>
> It would be good to also implement __atomic_add_unless().
>
> Something like so, if I got your asm right..
>
> static inline int __atomic_add_unless(atomic_t *v, int a, int u)
> {
> int old, tmp;
>
> __asm__ __volatile__(
> "1: l.lwa %0, 0(%2) \n"
> " l.sfeq %0, %4 \n"
> " l.bf 2f \n"
> " l.nop \n"
> " l.add %1, %0, %3 \n"
> " l.swa 0(%2), %1 \n"
> " l.bnf 1b \n"
> "2: l.nop \n"
> : "=&r"(old), "=&r" (tmp)
> : "r"(&v->counter), "r"(a), "r"(u)
> : "cc", "memory");
>
> return old;
> }
Ok, thanks this looks right. I tested it too and it looks to work ok.
Note, I still include <asm-generic/atomic.h> to avoid copy-n-pastes. So
I also wrapped __atomic_add_unless with #ifndef __atomic_add_unless in
the generic code.
-Stafford
