Re: [Query] CPUFreq: Why do we need policy->user_policy?

From: Rafael J. Wysocki
Date: Tue Aug 27 2013 - 17:09:53 EST


On Tuesday, August 27, 2013 10:04:52 PM Lan Tianyu wrote:
> 2013/8/27 Viresh Kumar <viresh.kumar@xxxxxxxxxx>:
> > On 26 August 2013 20:53, Lan Tianyu <lantianyu1986@xxxxxxxxx> wrote:
> >> So far as I know, it stores some user's config and cpufreq_update_policy()
> >> bases on the data in the struct to start a new policy. Cpu thermal driver
> >> ï/driver/thermal/cpu_cooling.cïalso will its value to update freq policy
> >> when receive a cpufreq policy adjust notification.
> >
> > Yeah, but how are these different from policy->min/max/policy/governor?
> > Why do we need to replicate this information?
>
> From my understanding.policy->min/max may be modified by some drivers
> but the user_policy only store user space config and should not be changed
> by other reason. :)

Yes, that was the original idea IIRC, so separate user settings from stuff that
may be changed internally by the kernel.

Thanks,
Rafael

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