Re: [BUG] cpufreq: constant cpu_khz

Arjan van de Ven
2008-08-25T18:22:57Z

On Mon, 25 Aug 2008 19:57:12 +0200
Ingo Molnar <mingo@elte.hu> wrote:

>
> * Dave Jones <davej@codemonkey.org.uk> wrote:
>
> > > hm, that too is due to the tsc.c unification - Alok Cc:-ed.
> > > Applied your fix to x86/urgent.
> >
> > ACKed-by: Dave Jones <davej@redhat.com>
> >
> > Good catch Peter. I'm puzzled how that bug was latent on 64bit for
> > so long with no-one realising though.
>
> i think it's the combination of these two factors:
>
> - bootup frequently is typically full-speed, so we calibrate things
> right
>
> - cpufreq events are relatively slow-scale - and when they trigger
> the system is definitely not under load. So how precisely the
> scheduler functions isnt all that important in such scenarios -
> there's tons of CPU power available.
>

- many many of the 64 bit capable cpus are constant-tsc anyway