From mboxrd@z Thu Jan  1 00:00:00 1970
From: Todd Poynor <toddpoynor@google.com>
Subject: Re: [PATCH] PM: OPP: introduce function to free cpufreq table
Date: Mon, 23 May 2011 17:05:49 -0700
Message-ID: <20110524000549.GA20225@google.com>
References: <1306192335-19883-1-git-send-email-nm@ti.com>
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To: Nishanth Menon <nm@ti.com>
Cc: linux-pm <linux-pm@lists.linux-foundation.org>, linux-omap <linux-omap@vger.kernel.org>, "Rafael J. Wysocki" <rjw@sisk.pl>

On Mon, May 23, 2011 at 06:12:15PM -0500, Nishanth Menon wrote:
> cpufreq table allocated by opp_init_cpufreq_table is better
> freed by OPP layer itself. This allows future modifications to
> the table handling to be transparent to the users.
...
> +void opp_free_cpufreq_table(struct device *dev,
> +				struct cpufreq_frequency_table **table)
> +{
> +	if (!table)
> +		return;
> +
> +	/* Pretend as if I am an updater */
> +	mutex_lock(&dev_opp_list_lock);
> +	kfree(*table);
> +	*table = NULL;
> +	mutex_unlock(&dev_opp_list_lock);
> +}

Not clear what the mutex protects here.  Currently it protects only
device opp list modifications.  opp_init_cpufreq_table holds the lock only
while looking up and walking the device opp list; the cpufreq table it
creates is not complete by the time the lock is dropped.


Todd