Re: [PATCH 05/10] nohz: New tick dependency mask

From: Peter Zijlstra
Date: Mon Aug 03 2015 - 08:43:59 EST


On Thu, Jul 23, 2015 at 06:42:10PM +0200, Frederic Weisbecker wrote:
> +unsigned long __tick_nohz_set_tick_dependency(enum tick_dependency_bit bit,
> + unsigned long *dep)
> +{
> + unsigned long prev;
> + unsigned long old = *dep;
> + unsigned long mask = BIT_MASK(bit);
> +
> + while ((prev = cmpxchg(dep, old, old | mask)) != old) {
> + old = prev;
> + cpu_relax();
> + }
> +
> + return prev;
> +}

That's typically called a fetch_or(). The function name, which is
entirely too long, also doesn't suggest a return value.
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