Re: more efficient current_is_keventd macro? [was Re: [lhcs-devel]Re: Kthread_create() never returns when called from worker_thread]

[Rusty Russell]

On Tue, 2004-03-09 at 09:36, Andrew Morton wrote:
> Srivatsa Vaddagiri <vatsa@xxxxxxxxxx> wrote:
> > int current_is_keventd(void)
> > {
> > +       int cpu = smp_processor_id();
> > +	cwq = keventd_wq->cpu_wq + cpu;
> > +	if (current == cwq->thread)
> > +		return 1;
> > +	else
> > +		return 0;
> > }
> 
> Is racy in the presence of preemption.

Actually, it's not, because if current *is* keventd we're nailed to the
CPU, and if it's not, we're going to return false either way.

But it *should* be fixed, simply as an example to others.

Cheers,
Rusty.
-- 
Anyone who quotes me in their signature is an idiot -- Rusty Russell

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