Re: Question: monolitic_clock, timer_{tsc,hpet} and CPUFREQ

From: Dominik Brodowski
Date: Sun Sep 07 2003 - 14:31:38 EST


On Fri, Sep 05, 2003 at 01:13:14AM -0700, john stultz wrote:
> On Thu, 2003-09-04 at 20:14, Dmitry Torokhov wrote:
> > I noticed that although timer_tsc registers cpufreq notifier to detect
> > frequency changes and adjust cpu_khz it does not set cyc2ns_scale. Is
> > monotonic clocks supposed to be also accurate?
>
> You are correct, without adjusting the cyc2ns_scale value
> monotonic_clock() will not be accurate on freq changing hardware.

Seems to be a necessary update. Thanks for noting this.


> Looks fine to me. Although I don't have any cpufreq enabled hardware, so
> I'm unable to test this (main cause I never added it myself).

/me has cpufreq enabled hardware -- but how can I accurately debug
monotonic_ticks()?

Dominik
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