Re: [PATCH] PM: OPP: introduce function to free cpufreq table

[Todd Poynor <toddpoynor@google.com>]

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