Re: [PATCH] thermal: cpu_cooling: Remove usage of devm functions

From: Zhang Rui
Date: Sat Oct 10 2015 - 04:50:23 EST


On Wed, 2015-08-19 at 11:52 +0530, Vaishali Thakkar wrote:
> In the function cpufreq_get_requested_power, the memory allocated
> for load_cpu is live within the function only. And after the
> allocation it is immediately freed with devm_kfree. There is no
> need to allocate memory for load_cpu with devm function so replace
> devm_kcalloc with kcalloc and devm_kfree with kfree.
>
> Signed-off-by: Vaishali Thakkar <vthakkar1994@xxxxxxxxx>
> ---
> This patch is having one checkpatch.pl warning which suggests that
> kfree(NULL) is safe. But I think leaving code with if is nice
> because it reflects the fact that kcalloc was under an if. So, I
> have ignored checkpatch. If maintainer wants me to go for changing
> things, I am fine with it too.

Applied. And I've removed the "if (load_cpu)" for kfree() to avoid
warning reports.

thanks,
rui
> ---
> drivers/thermal/cpu_cooling.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
> index 620dcd4..babf8b3 100644
> --- a/drivers/thermal/cpu_cooling.c
> +++ b/drivers/thermal/cpu_cooling.c
> @@ -584,8 +584,7 @@ static int cpufreq_get_requested_power(struct thermal_cooling_device *cdev,
> if (trace_thermal_power_cpu_get_power_enabled()) {
> u32 ncpus = cpumask_weight(&cpufreq_device->allowed_cpus);
>
> - load_cpu = devm_kcalloc(&cdev->device, ncpus, sizeof(*load_cpu),
> - GFP_KERNEL);
> + load_cpu = kcalloc(ncpus, sizeof(*load_cpu), GFP_KERNEL);
> }
>
> for_each_cpu(cpu, &cpufreq_device->allowed_cpus) {
> @@ -609,7 +608,7 @@ static int cpufreq_get_requested_power(struct thermal_cooling_device *cdev,
> ret = get_static_power(cpufreq_device, tz, freq, &static_power);
> if (ret) {
> if (load_cpu)
> - devm_kfree(&cdev->device, load_cpu);
> + kfree(load_cpu);
> return ret;
> }
>
> @@ -618,7 +617,7 @@ static int cpufreq_get_requested_power(struct thermal_cooling_device *cdev,
> &cpufreq_device->allowed_cpus,
> freq, load_cpu, i, dynamic_power, static_power);
>
> - devm_kfree(&cdev->device, load_cpu);
> + kfree(load_cpu);
> }
>
> *power = static_power + dynamic_power;


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/