2015-08-19 06:22:25

by Vaishali Thakkar

[permalink] [raw]
Subject: [PATCH] thermal: cpu_cooling: Remove usage of devm functions

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 <[email protected]>
---
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.
---
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;
--
1.9.1


2015-08-19 08:24:20

by Viresh Kumar

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

On Wed, Aug 19, 2015 at 11:52 AM, Vaishali Thakkar
<[email protected]> 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 <[email protected]>
> ---
> 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.

I will rather ask you to do this:

diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
index 620dcd405ff6..a04055ea5d94 100644
--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -584,8 +584,8 @@ 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(&cdev->device, ncpus, sizeof(*load_cpu),
+ GFP_KERNEL);
}

for_each_cpu(cpu, &cpufreq_device->allowed_cpus) {
@@ -607,22 +607,20 @@ static int cpufreq_get_requested_power(struct
thermal_cooling_device *cdev,

dynamic_power = get_dynamic_power(cpufreq_device, freq);
ret = get_static_power(cpufreq_device, tz, freq, &static_power);
- if (ret) {
- if (load_cpu)
- devm_kfree(&cdev->device, load_cpu);
- return ret;
- }
+ if (ret)
+ goto free;

- if (load_cpu) {
+ 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);
- }
-
*power = static_power + dynamic_power;
- return 0;
+
+free:
+ kfree(&cdev->device, load_cpu);
+
+ return ret;
}

2015-08-19 11:38:19

by Vaishali Thakkar

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

On Wed, Aug 19, 2015 at 1:54 PM, Viresh Kumar <[email protected]> wrote:
> On Wed, Aug 19, 2015 at 11:52 AM, Vaishali Thakkar
> <[email protected]> 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 <[email protected]>
>> ---
>> 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.
>
> I will rather ask you to do this:

Ok. I was not sure about introducing new label. Thanks.

I will send v2 with the changes you pointed.

> diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
> index 620dcd405ff6..a04055ea5d94 100644
> --- a/drivers/thermal/cpu_cooling.c
> +++ b/drivers/thermal/cpu_cooling.c
> @@ -584,8 +584,8 @@ 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(&cdev->device, ncpus, sizeof(*load_cpu),
> + GFP_KERNEL);
> }
>
> for_each_cpu(cpu, &cpufreq_device->allowed_cpus) {
> @@ -607,22 +607,20 @@ static int cpufreq_get_requested_power(struct
> thermal_cooling_device *cdev,
>
> dynamic_power = get_dynamic_power(cpufreq_device, freq);
> ret = get_static_power(cpufreq_device, tz, freq, &static_power);
> - if (ret) {
> - if (load_cpu)
> - devm_kfree(&cdev->device, load_cpu);
> - return ret;
> - }
> + if (ret)
> + goto free;
>
> - if (load_cpu) {
> + 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);
> - }
> -
> *power = static_power + dynamic_power;
> - return 0;
> +
> +free:
> + kfree(&cdev->device, load_cpu);
> +
> + return ret;
> }



--
Vaishali

2015-08-19 11:57:59

by Vaishali Thakkar

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

On Wed, Aug 19, 2015 at 1:54 PM, Viresh Kumar <[email protected]> wrote:
> On Wed, Aug 19, 2015 at 11:52 AM, Vaishali Thakkar
> <[email protected]> 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 <[email protected]>
>> ---
>> 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.
>
> I will rather ask you to do this:
>
> diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
> index 620dcd405ff6..a04055ea5d94 100644
> --- a/drivers/thermal/cpu_cooling.c
> +++ b/drivers/thermal/cpu_cooling.c
> @@ -584,8 +584,8 @@ 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(&cdev->device, ncpus, sizeof(*load_cpu),
> + GFP_KERNEL);
> }

Sorry. I forgot to ask you one more thing. devm_kcalloc takes one more
argument then
kcalloc. So, the change I did is correct I guess. And I'm not sure why
you suggested this
change? I assume you just want me to correct in my patch for last
argument. But that line
also comes under 80 characters.

> for_each_cpu(cpu, &cpufreq_device->allowed_cpus) {
> @@ -607,22 +607,20 @@ static int cpufreq_get_requested_power(struct
> thermal_cooling_device *cdev,
>
> dynamic_power = get_dynamic_power(cpufreq_device, freq);
> ret = get_static_power(cpufreq_device, tz, freq, &static_power);
> - if (ret) {
> - if (load_cpu)
> - devm_kfree(&cdev->device, load_cpu);
> - return ret;
> - }
> + if (ret)
> + goto free;
>
> - if (load_cpu) {
> + 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);
> - }
> -
> *power = static_power + dynamic_power;
> - return 0;
> +
> +free:
> + kfree(&cdev->device, load_cpu);
> +
> + return ret;
> }



--
Vaishali

2015-08-19 12:02:16

by Viresh Kumar

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

On 19-08-15, 17:27, Vaishali Thakkar wrote:
> > I will rather ask you to do this:
> >
> > diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
> > index 620dcd405ff6..a04055ea5d94 100644
> > --- a/drivers/thermal/cpu_cooling.c
> > +++ b/drivers/thermal/cpu_cooling.c
> > @@ -584,8 +584,8 @@ 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(&cdev->device, ncpus, sizeof(*load_cpu),
> > + GFP_KERNEL);
> > }
>
> Sorry. I forgot to ask you one more thing. devm_kcalloc takes one more
> argument then
> kcalloc. So, the change I did is correct I guess.

Right, there is an extra argument in my code.

--
viresh

2015-08-27 01:57:11

by Viresh Kumar

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

On Wed, Aug 19, 2015 at 11:52 AM, Vaishali Thakkar
<[email protected]> 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 <[email protected]>
> ---
> 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.
> ---
> 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;

Acked-by: Viresh Kumar <[email protected]>

@Eduardo: Ignore V2 and apply this one :)

2015-08-27 08:59:25

by Javi Merino

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

On Wed, Aug 19, 2015 at 07:22:19AM +0100, 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 <[email protected]>

Acked-by: Javi Merino <[email protected]>

> ---
> 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.

I wouldn't have minded changing the

if (load_cpu)
kfree(load_cpu)

to just "kfree(load_cpu)" but I don't have a strong preference. I'm
also happy with the patch as it is.

Cheers,
Javi

> ---
> 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;