[PATCH] PM / OPP: optimize dev_pm_opp_set_rate() a bit
Viresh Kumar
viresh.kumar at linaro.org
Fri Jul 22 09:21:51 PDT 2016
On 22-07-16, 20:42, Jisheng Zhang wrote:
> static int _set_opp_voltage(struct device *dev, struct regulator *reg,
> unsigned long u_volt, unsigned long u_volt_min,
> unsigned long u_volt_max)
> @@ -586,9 +565,24 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
> return -EINVAL;
> }
>
> - clk = _get_opp_clk(dev);
> - if (IS_ERR(clk))
> + rcu_read_lock();
> +
> + opp_table = _find_opp_table(dev);
> + if (IS_ERR(opp_table)) {
> + dev_err(dev, "%s: device opp doesn't exist\n", __func__);
> + rcu_read_unlock();
> + return PTR_ERR(opp_table);
> + }
> +
> + clk = opp_table->clk;
> + if (IS_ERR(clk)) {
> + dev_err(dev, "%s: No clock available for the device\n",
> + __func__);
> + rcu_read_unlock();
> return PTR_ERR(clk);
> + }
> +
> + rcu_read_unlock();
It is not _safe_ to use opp_table pointer after the rcu_read_unlock()
here.
--
viresh
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