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SubjectRe: [PATCH] Revert "cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency"
On 22-07-16, 23:46, Rafael J. Wysocki wrote:
> On Friday, July 22, 2016 02:28:52 PM Viresh Kumar wrote:
> > On 22-07-16, 23:31, Rafael J. Wysocki wrote:
> > > > cpufreq.c
> > > >
> > > > if (policy->governor->max_transition_latency &&
> > > > policy->cpuinfo.transition_latency >
> > > > policy->governor->max_transition_latency) {
> > > >
> > > > - And this check will always fail, unless max_transition_latency is zero.
> > >
> > > Why would it fail? If governor->max_transition_latency is non-zero, but less
> > > than UNIT_MAX, the condition checked will be true to my eyes.
> >
> > Bad wording. Sorry.
> >
> > I meant, this 'if' check will always succeed (as you also noted), and
> > so we will always get the error message reported in this patch.
>
> Not always, but for drivers setting cpuinfo.transition_latency to CPUFREQ_ETERNAL.

So the drivers which have set their transition_latency to
CPUFREQ_ETERNAL, can't use ondemand governor unless
governor->max_transition_latency is set to 0 from userspace.

What should be done about this patch then ? It broke in late 2015.

--
viresh

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