linux-kernel - Re: [PATCH] Revert "cpufreq: pcc-cpufreq: update default value of cpuinfo_transition

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Message-ID: <20160722212852.GE3122@ubuntu>
Date:	Fri, 22 Jul 2016 14:28:52 -0700
From:	Viresh Kumar <viresh.kumar@...aro.org>
To:	"Rafael J. Wysocki" <rjw@...ysocki.net>
Cc:	Andreas Herrmann <aherrmann@...e.com>,
	Jacob Tanenbaum <jtanenba@...hat.com>, stable@...r.kernel.org,
	linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] Revert "cpufreq: pcc-cpufreq: update default value of
 cpuinfo_transition_latency"

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.

cpufreq: ondemand governor failed, too long transition latency of HW,
fallback to performance governor

-- 
viresh