Re: rcu_sched self-detected stall on CPU

Paul E. McKenney
2022-04-07T15:16:44Z

On Thu, Apr 07, 2022 at 12:07:34PM +0200, Miguel Ojeda wrote:
> On Thu, Apr 7, 2022 at 4:27 AM Zhouyi Zhou <zhouzhouyi@gmail.com> wrote:
> >
> > Yes, this happens within 30 seconds after kernel boot. If we take all
> > into account (qemu preparing, kernel loading), we can do one test
> > within 54 seconds.
>
> When it does not trigger, the run should be 20 seconds quicker than
> that (e.g. 10 seconds), since we don't wait for the stall timeout. I
> guess the timeout could also be reduced a fair bit to make failures
> quicker, but they do not contribute as much as the successes anyway.

Ah. So you would instead look for boot to have completed within 10
seconds? Either way, reliable automation might well more important than
reduction in time.

> Thanks a lot for running the bisect on that server, Zhouyi!

What Miguel said!

Thanx, Paul