linux-kernel - Re: [Update][PATCH] cpufreq: Do not hold driver module references for additional policy CPUs

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Message-ID: <CAKohpokbd=xX-DqVeEZOnGftZuE-54RDShpMJgFPskRc3CkZ5w@mail.gmail.com>
Date:	Fri, 2 Aug 2013 16:00:47 +0530
From:	Viresh Kumar <viresh.kumar@...aro.org>
To:	"Rafael J. Wysocki" <rjw@...k.pl>
Cc:	Linux PM list <linux-pm@...r.kernel.org>, cpufreq@...r.kernel.org,
	"Srivatsa S. Bhat" <srivatsa.bhat@...ux.vnet.ibm.com>,
	LKML <linux-kernel@...r.kernel.org>,
	Lists linaro-kernel <linaro-kernel@...ts.linaro.org>
Subject: Re: [Update][PATCH] cpufreq: Do not hold driver module references for
 additional policy CPUs

On 2 August 2013 02:23, Rafael J. Wysocki <rjw@...k.pl> wrote:
> To remove that inconsistency make cpufreq_add_policy_cpu() execute
> cpufreq_cpu_put() for the given policy before returning, which
> decrements the driver module refcount so that it will be 0 after
> __cpufreq_add_dev() returns.  Moreover, remove the cpufreq_cpu_get()
> call from cpufreq_add_dev_symlink(), since both the policy refcount
> and the driver module refcount are nonzero when it is called and they
> don't need to be bumped up by it.

Sorry for creating so many problems but my concerns with this patch
aren't yet over :(

Should we increment policy refcount or kobj refcount for every cpu it
is used on? I think yes, that's probably the right way of doing it.

And so we simply can't remove calls to cpufreq_cpu_get() from
cpufreq_add_dev_symlink() routine and also from
cpufreq_add_policy_cpu()..
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