Re: [PATCH] rcutorture: Traverse possible cpu to set maxcpu in rcu_nocb_toggle()

From: Frederic Weisbecker
Date: Tue Aug 29 2023 - 05:25:34 EST


On Mon, Aug 28, 2023 at 05:51:09PM -0400, Joel Fernandes wrote:
> I think the issue is the loop later in the function does
> not try to toggle cpus that came online too late.
>
> So it does not test offloading on all CPUs just because max got updated too
> late.

Right, and therefore for_each_possible_cpu() or for_each_present_cpu()
should be fine to iterate since it's ok to try to toggle an offline CPU.

>
> One fix could be to periodically check in the loop if a new cpu at maxcpu + 1
> ever got onlined. If it did, update the maxcpu.

Is it worth the complication though?

Thanks.

>
> Thanks.
>
>
> >
> > Thanks.