Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1448667

Re: [PATCH] PM / OPP: optimize dev_pm_opp_set_rate() a bit

Show all headers | View raw

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

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH] PM / OPP: optimize dev_pm_opp_set_rate() a bit Jisheng Zhang <jszhang@marvell.com> - 2016-07-22 14:50 +0200
  Re: [PATCH] PM / OPP: optimize dev_pm_opp_set_rate() a bit Viresh Kumar <viresh.kumar@linaro.org> - 2016-07-22 18:30 +0200
    Re: [PATCH] PM / OPP: optimize dev_pm_opp_set_rate() a bit Jisheng Zhang <jszhang@marvell.com> - 2016-07-25 07:20 +0200
  Re: [PATCH] PM / OPP: optimize dev_pm_opp_set_rate() a bit Jisheng Zhang <jszhang@marvell.com> - 2016-07-25 07:30 +0200
    Re: [PATCH] PM / OPP: optimize dev_pm_opp_set_rate() a bit Jisheng Zhang <jszhang@marvell.com> - 2016-07-25 08:20 +0200

csiph-web