Re: [PATCH] cpuidle: menu: Retain tick when shallow state is selected

From: leo . yan
Date: Wed Aug 22 2018 - 08:03:42 EST


On Wed, Aug 22, 2018 at 08:02:00PM +0800, Leo Yan wrote:

[...]

> > + if (!tick_nohz_tick_stopped()) {
> > + /*
> > + * If the state selected so far is shallow,
> > + * waking up early won't hurt, so retain the
> > + * tick in that case and let the governor run
> > + * again in the next iteration of the loop.
> > + */
> > + expected_interval = drv->states[idx].target_residency;
> > + break;
> > + }
> > +
>
> This is reliable, how we can rely on a shallow idle state target
> residency to decide if need to stop a tick or not?

s/This is reliable/This isn't reliable

>
> > /*
> > * If the state selected so far is shallow and this
> > * state's target residency matches the time till the
> >