Re: [patch] x86: scale cyc_2_nsec according to CPU frequency

[Ingo Molnar]

* Arjan van de Ven <arjan@xxxxxxxxxxxxx> wrote:

> > > > Firstly, we dont need the 'offset' anymore because cpu_clock() 
> > > > maintains offsets itself.
> > > 
> > > Yes, but a lower quality one. __update_rq_clock tries to 
> > > compensate large jumping clocks with a jiffy resolution, while my 
> > > offset arranges for a very smooth frequency transition.
> > 
> > yes, but that would be easy to fix up via calling 
> > sched_clock_idle_wakeup_event(0) when doing a frequency transition, 
> > without burdening the normal sched_clock() codepath with the offset. 
> > See the attached latest version.
> 
> can this deal with dual/quad core where the frequency of one core 
> changes if the sofware changes the frequency of the other core?

doesnt the notifier still get run on the target CPU?

	Ingo
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