Re: [tip: sched/hrtick] sched/eevdf: Fix HRTICK duration

[Peter Zijlstra]

On Fri, Mar 20, 2026 at 08:29:11PM +0530, Shrikanth Hegde wrote:

> > +	/*
> > +	 * Correct for instantaneous load of other classes.
> > +	 */
> > +	util += cpu_util_irq(rq);
> > +	if (util && util < 1024) {
> > +		scale *= 1024;
> > +		scale /= (1024 - util);
> > +	}
> 
> Comments/Changelog says other classes.
> 
> Then why not consider cpu_util_dl, cpu_util_rq too?
> Is there a reason why these are not taken into calculations?

Damn, forgot to fix that comment.

So yes, it used to correct for those, but then I realized that the
hrtick is strictly for current. So running RT/DL tasks means current is
different.

The only thing that can actually interrupt current and soak time are
interrupts.

Does that make sense?