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

From: Geert Uytterhoeven
Date: Fri Jul 10 2015 - 05:10:42 EST


Hi Peter,

On Thu, Jul 9, 2015 at 7:29 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> 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

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

> +}
> +#endif
> +
> +static inline __deprecated void atomic_clear_mask(unsigned int mask, atomic_t *v)
> +{
> + atomic_nand(mask, v);
> +}

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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