Re: [PATCH 1/2] CPUFREQ: Remove unneeded dbs_mutexes from ondemand and conservative governors

Pavel Machek
2009-07-01T09:02:16Z

On Thu 2009-06-25 16:01:24, Thomas Renninger wrote:
> Comment from Venkatesh:
> ...
> This mutex is just serializing the changes to those variables. I could't
> think of any functionality issues of not having the lock as such.
>
> -> rip it out.
>
> CC: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
> Signed-off-by: Thomas Renninger <trenn@suse.de>

> static struct dbs_tuners {
> @@ -236,10 +222,7 @@ static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused,
> if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
> return -EINVAL;
>
> - mutex_lock(&dbs_mutex);
> dbs_tuners_ins.sampling_down_factor = input;
> - mutex_unlock(&dbs_mutex);
> -

You'd need to make s_down_factor atomic_t for this to work....
Pavel
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