On Wed, Jan 28, 2015 at 05:31:06PM +0000, Steven Rostedt wrote:
> On Wed, 28 Jan 2015 17:00:36 +0000
> Javi Merino <[email protected]> wrote:
>
> > + if (trace_thermal_power_cpu_limit_enabled() && load_cpu) {
> > + trace_thermal_power_cpu_get_power(
> > + &cpufreq_device->allowed_cpus,
> > + freq, load_cpu, i, dynamic_power, static_power);
> > +
> > + devm_kfree(&cdev->device, load_cpu);
>
> You may want to move the devm_kfree() out of the
> trace_thermal_power_cpu_limit_enabled() check. There could be a race
> where that gets disabled while this function is running and you just
> leaked memory.
>
> if (load_cpu)
> devm_kfree(&cdev->device, load_cpu);
>
> should be done by itself.
Good catch! I've changed it to
if (load_cpu) {
trace_thermal_power_cpu_get_power(
&cpufreq_device->allowed_cpus,
freq, load_cpu, i, dynamic_power, static_power);
devm_kfree(&cdev->device, load_cpu);
}
This way, if the trace is disabled while in the function,
trace_thermal_power_cpu_get_power() doesn't get executed but you free
load_cpu. If the opposite happens (the trace gets enabled while in
the function), load_cpu is NULL and you don't pass the NULL pointer to
trace_thermal_power_cpu_get_power().
Cheers,
Javi