Re: [PATCH 1/11] Add generic helpers for arch IPI function calls

[Jens Axboe]

On Thu, Apr 24 2008, Russell King wrote:
> On Tue, Apr 22, 2008 at 08:50:17PM +0200, Jens Axboe wrote:
> > +		data->csd.func(data->csd.info);
> > +
> > +		spin_lock(&data->lock);
> > +		cpu_clear(cpu, data->cpumask);
> > +		WARN_ON(data->refs == 0);
> > +		data->refs--;
> > +		refs = data->refs;
> 
> Probably a silly question, but what does data->refs do that
> cpus_empty(data->cpumask) wouldn't do?  (as indeed ARM presently does.)

I guess it can be marginally slower for NR_CPUS > BITS_PER_LONG,
otherwise there's absolutely no reason to have a seperate ref counter.

-- 
Jens Axboe

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/