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Subject: Re: [PATCH 1/3] cpuidle/menu: stop seeking deeper idle if current
 state is too deep
To: Rik van Riel <riel@redhat.com>, Alex Shi <alex.shi@linaro.org>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
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References: <1483630187-29622-1-git-send-email-alex.shi@linaro.org>
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 <1483631039.25514.1.camel@redhat.com>
Cc: linux-pm@vger.kernel.org, Ulf Hansson <ulf.hansson@linaro.org>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>
From: Arjan van de Ven <arjan@linux.intel.com>
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Date: Thu, 5 Jan 2017 07:55:24 -0800
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On 1/5/2017 7:43 AM, Rik van Riel wrote:
> On Thu, 2017-01-05 at 23:29 +0800, Alex Shi wrote:
>> The obsolete commit 71abbbf85 want to introduce a dynamic cstates,
>> but it was removed for long time. Just left the nonsense deeper
>> cstate
>> checking.
>>
>> Since all target_residency and exit_latency are going longer in
>> deeper
>> idle state, no needs to waste some cpu cycle on useless seeking.
>
> Makes me wonder if it would be worth documenting the
> requirement that c-states be listed in increasing
> order?

or better, a boot time quick check...