linux-kernel - Re: [PATCH 7/8] cpufreq: Preserve policy structure across suspend/resume

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Date:	Mon, 15 Jul 2013 15:25:47 +0530
From:	Viresh Kumar <viresh.kumar@...aro.org>
To:	"Srivatsa S. Bhat" <srivatsa.bhat@...ux.vnet.ibm.com>
Cc:	rjw@...k.pl, toralf.foerster@....de, robert.jarzmik@...el.com,
	durgadoss.r@...el.com, tianyu.lan@...el.com,
	lantianyu1986@...il.com, dirk.brandewie@...il.com,
	stern@...land.harvard.edu, linux-pm@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 7/8] cpufreq: Preserve policy structure across suspend/resume

Hi Srivatsa,

I may be wrong but it looks something is wrong in this patch.

On 12 July 2013 03:47, Srivatsa S. Bhat
<srivatsa.bhat@...ux.vnet.ibm.com> wrote:
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c

> @@ -1239,29 +1263,40 @@ static int __cpufreq_remove_dev(struct device *dev,
>         if ((cpus == 1) && (cpufreq_driver->target))
>                 __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT);
>
> -       pr_debug("%s: removing link, cpu: %d\n", __func__, cpu);
> -       cpufreq_cpu_put(data);
> +       if (!frozen) {
> +               pr_debug("%s: removing link, cpu: %d\n", __func__, cpu);
> +               cpufreq_cpu_put(data);

So, we don't decrement usage count here. But we are still increasing
counts on cpufreq_add_dev after resume, isn't it?

So, we wouldn't be able to free policy struct once all the cpus of a
policy are removed after suspend/resume has happened once.
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