Date: Thu, 3 Mar 2016 22:12:16 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Linux PM list <linux-pm@vger.kernel.org>,
        Juri Lelli <juri.lelli@arm.com>,
        Steve Muckle <steve.muckle@linaro.org>,
        ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Michael Turquette <mturquette@baylibre.com>
Subject: Re: [PATCH 5/6] cpufreq: Support for fast frequency switching
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On Thu, Mar 03, 2016 at 09:56:40PM +0100, Rafael J. Wysocki wrote:
> On Thu, Mar 3, 2016 at 12:16 PM, Peter Zijlstra <peterz@infradead.org> wrote:
> > On Wed, Mar 02, 2016 at 03:12:33AM +0100, Rafael J. Wysocki wrote:
> >> The most important change from the previous version is that the
> >> ->fast_switch() callback takes an additional "relation" argument
> >> and now the governor can use it to choose a selection method.
> >
> >> +unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
> >> +                                   unsigned int target_freq,
> >> +                                   unsigned int relation)
> >
> > Would it make sense to replace the {target_freq, relation} pair with
> > something like the CPPC {min_freq, max_freq} pair?
> 
> Yes, it would in general, but since I use __cpufreq_driver_target() in
> the "slow driver" case, that would need to be reworked too for
> consistency.  So I'd prefer to do that later.

OK, fair enough.