Re: [patch] sched: fix b5d9d734 blunder in task_new_fair()

Mike Galbraith
2009-11-24T18:22:03Z

On Tue, 2009-11-24 at 18:54 +0100, Peter Zijlstra wrote:
> On Tue, 2009-11-24 at 18:35 +0100, Peter Zijlstra wrote:
> > On Tue, 2009-11-24 at 18:07 +0100, Mike Galbraith wrote:
> > > > if (p->sched_class->task_new) {
> > > > /* can detect migration through: task_cpu(p) != smp_processor_id() */
> > >
> > > What if the parent was migrated before we got here?
> >
> > Well, the only case it really matters for is the child_runs_first crap,
> > which is basically broken on SMP anyway, so I don't think we care too
> > much if we race here.
> >
> > Unless I missed some detail that is ;-)
>
>
> Also, we're running all this from the parent context, and we have
> preemption disabled, we're not going anywhere.

In sched_fork() and wake_up_new_process(), but in between?

-Mike