linux-kernel - Re: [PATCH] cpufreq: Skip all governor-related actions for cpufreq

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Message-ID: <20160407042820.GA14903@vireshk-i7>
Date:	Thu, 7 Apr 2016 09:58:20 +0530
From:	Viresh Kumar <viresh.kumar@...aro.org>
To:	"Rafael J. Wysocki" <rjw@...ysocki.net>
Cc:	Linux PM list <linux-pm@...r.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>
Subject: Re: [PATCH] cpufreq: Skip all governor-related actions for
 cpufreq_suspended set

On 07-04-16, 03:29, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
> 
> Since governor operations are generally skipped if cpufreq_suspended
> is set, do nothing at all in cpufreq_start_governor() and
> cpufreq_exit_governor() in that case.
> 
> In particular, this prevents fast frequency switching from being
> disabled after a suspend-to-RAM cycle on all CPUs except for the
> boot one.

static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event)
{
	int ret;

	/* Don't start any governor operations if we are entering suspend */
	if (cpufreq_suspended)
		return 0;

        ...

}

Above already guarantees that we would start/stop governors. Why do we
need this change then ?


-- 
viresh