Re: [RFC][PATCH 23/24] atomic: Collapse all atomic_{set,clear}_mask definitions

Peter Zijlstra
2015-07-10T10:40:15Z

On Fri, Jul 10, 2015 at 11:10:33AM +0200, Geert Uytterhoeven wrote:
> Hi Peter,
>
> On Thu, Jul 9, 2015 at 7:29 PM, Peter Zijlstra <peterz@infradead.org> wrote:
> > --- a/include/linux/atomic.h
> > +++ b/include/linux/atomic.h
> > @@ -28,6 +28,23 @@ static inline int atomic_add_unless(atom
> > #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
> > #endif
> >
> > +#ifndef atomic_nand
> > +static inline void atomic_nand(int i, atomic_t *v)
> > +{
> > + atomic_and(~i, v);
>
> That sounds like a misnomer...
>
> Your NAND is "A & ~B", while my[*] NAND is "~(A & B)"?
>
> [*] https://en.wikipedia.org/wiki/NAND_logic

Right you are.

> What about atomic_clear()? (Is atomic_bic() too ARM-centric?)

atomic_and_not() ?