Re: [PATCH 3/5] sched: cpufreq: call cpufreq hook from remote CPUs

[Steve Muckle]

On Thu, May 19, 2016 at 11:06:14PM +0200, Rafael J. Wysocki wrote:
> > In the case of a remote update the hook has to run (or not) after it is
> > known whether preemption will occur so we don't do needless work or
> > IPIs. If the policy CPUs aren't known in the scheduler then the early
> > hook will always need to be called along with an indication that it is
> > the early hook being called. If it turns out to be a remote update it
> > could then be deferred to the later hook, which would only be called
> > when a remote update has been deferred and preemption has not occurred.
> >
> > This means two hook inovcations for a remote non-preempting wakeup
> > though instead of one.  Perhaps this is a good middle ground on code
> > churn vs. optimization though.
> 
> I would think so.

Ok, I will pursue this approach.

thanks,
Steve