diff mbox

[RFC,13/27] ARM: cpuidle: Add runtime PM support for CPU idle

Message ID 1447799871-56374-14-git-send-email-lina.iyer@linaro.org (mailing list archive)
State RFC
Delegated to: Andy Gross
Headers show

Commit Message

Lina Iyer Nov. 17, 2015, 10:37 p.m. UTC
Notify runtime PM when the CPU is going to be powered off in the idle
state. This allows for runtime PM suspend/resume of the CPU as well as
its PM domain.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
---
 drivers/cpuidle/cpuidle-arm.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Zhaoyang Huang Nov. 18, 2015, 8:50 a.m. UTC | #1
On 18 November 2015 at 06:37, Lina Iyer <lina.iyer@linaro.org> wrote:
> Notify runtime PM when the CPU is going to be powered off in the idle
> state. This allows for runtime PM suspend/resume of the CPU as well as
> its PM domain.
>
> Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
> ---
>  drivers/cpuidle/cpuidle-arm.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/drivers/cpuidle/cpuidle-arm.c b/drivers/cpuidle/cpuidle-arm.c
> index 545069d..8e72a23 100644
> --- a/drivers/cpuidle/cpuidle-arm.c
> +++ b/drivers/cpuidle/cpuidle-arm.c
> @@ -11,13 +11,16 @@
>
>  #define pr_fmt(fmt) "CPUidle arm: " fmt
>
> +#include <linux/cpu.h>
>  #include <linux/cpuidle.h>
>  #include <linux/cpumask.h>
>  #include <linux/cpu_pm.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
> +#include <linux/pm_runtime.h>
>  #include <linux/slab.h>
> +#include <linux/rcupdate.h>
>
>  #include <asm/cpuidle.h>
>
> @@ -45,6 +48,10 @@ static int arm_enter_idle_state(struct cpuidle_device *dev,
>
>         ret = cpu_pm_enter();
>         if (!ret) {
> +               struct device *cpu_dev = get_cpu_device(dev->cpu);
> +
> +               RCU_NONIDLE(pm_runtime_put_sync_suspend(cpu_dev));
By my test, it seems that the usage_count of cpu device will be
decrease to -1 and the code never runs here. If it need a runtime_put
somewhere?
> +
>                 /*
>                  * Pass idle state index to cpu_suspend which in turn will
>                  * call the CPU ops suspend protocol with idle index as a
> @@ -52,6 +59,7 @@ static int arm_enter_idle_state(struct cpuidle_device *dev,
>                  */
>                 arm_cpuidle_suspend(idx);
>
> +               RCU_NONIDLE(pm_runtime_get_sync(cpu_dev));
>                 cpu_pm_exit();
>         }
>
> --
> 2.1.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Lina Iyer Nov. 18, 2015, 2:17 p.m. UTC | #2
On Wed, Nov 18 2015 at 01:50 -0700, Zhaoyang Huang wrote:
>On 18 November 2015 at 06:37, Lina Iyer <lina.iyer@linaro.org> wrote:
>> Notify runtime PM when the CPU is going to be powered off in the idle
>> state. This allows for runtime PM suspend/resume of the CPU as well as
>> its PM domain.
>>
>> Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
>> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
>> Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
>> ---
>>  drivers/cpuidle/cpuidle-arm.c | 8 ++++++++
>>  1 file changed, 8 insertions(+)
>>
>> diff --git a/drivers/cpuidle/cpuidle-arm.c b/drivers/cpuidle/cpuidle-arm.c
>> index 545069d..8e72a23 100644
>> --- a/drivers/cpuidle/cpuidle-arm.c
>> +++ b/drivers/cpuidle/cpuidle-arm.c
>> @@ -11,13 +11,16 @@
>>
>>  #define pr_fmt(fmt) "CPUidle arm: " fmt
>>
>> +#include <linux/cpu.h>
>>  #include <linux/cpuidle.h>
>>  #include <linux/cpumask.h>
>>  #include <linux/cpu_pm.h>
>>  #include <linux/kernel.h>
>>  #include <linux/module.h>
>>  #include <linux/of.h>
>> +#include <linux/pm_runtime.h>
>>  #include <linux/slab.h>
>> +#include <linux/rcupdate.h>
>>
>>  #include <asm/cpuidle.h>
>>
>> @@ -45,6 +48,10 @@ static int arm_enter_idle_state(struct cpuidle_device *dev,
>>
>>         ret = cpu_pm_enter();
>>         if (!ret) {
>> +               struct device *cpu_dev = get_cpu_device(dev->cpu);
>> +
>> +               RCU_NONIDLE(pm_runtime_put_sync_suspend(cpu_dev));
>By my test, it seems that the usage_count of cpu device will be
>decrease to -1 and the code never runs here. If it need a runtime_put
>somewhere?

You shouldn't have to. Pls make sure all the patches are pulled in and
compiles successfully.

Let me know if you still run into issues.

Thanks,
Lina

>> +
>>                 /*
>>                  * Pass idle state index to cpu_suspend which in turn will
>>                  * call the CPU ops suspend protocol with idle index as a
>> @@ -52,6 +59,7 @@ static int arm_enter_idle_state(struct cpuidle_device *dev,
>>                  */
>>                 arm_cpuidle_suspend(idx);
>>
>> +               RCU_NONIDLE(pm_runtime_get_sync(cpu_dev));
>>                 cpu_pm_exit();
>>         }
>>
>> --
>> 2.1.4
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-pm" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Kevin Hilman Nov. 19, 2015, 10:10 p.m. UTC | #3
Lina Iyer <lina.iyer@linaro.org> writes:

> Notify runtime PM when the CPU is going to be powered off in the idle
> state. This allows for runtime PM suspend/resume of the CPU as well as
> its PM domain.
>
> Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
> ---
>  drivers/cpuidle/cpuidle-arm.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/drivers/cpuidle/cpuidle-arm.c b/drivers/cpuidle/cpuidle-arm.c
> index 545069d..8e72a23 100644
> --- a/drivers/cpuidle/cpuidle-arm.c
> +++ b/drivers/cpuidle/cpuidle-arm.c
> @@ -11,13 +11,16 @@
>  
>  #define pr_fmt(fmt) "CPUidle arm: " fmt
>  
> +#include <linux/cpu.h>
>  #include <linux/cpuidle.h>
>  #include <linux/cpumask.h>
>  #include <linux/cpu_pm.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
> +#include <linux/pm_runtime.h>
>  #include <linux/slab.h>
> +#include <linux/rcupdate.h>
>  
>  #include <asm/cpuidle.h>
>  
> @@ -45,6 +48,10 @@ static int arm_enter_idle_state(struct cpuidle_device *dev,
>  
>  	ret = cpu_pm_enter();
>  	if (!ret) {
> +		struct device *cpu_dev = get_cpu_device(dev->cpu);
> +
> +		RCU_NONIDLE(pm_runtime_put_sync_suspend(cpu_dev));
> +

A comment in the changelog about the use of _put_sync_suspend() instead
of a normal _put_sync() would be helpful for this patch.

Kevin
--
To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/drivers/cpuidle/cpuidle-arm.c b/drivers/cpuidle/cpuidle-arm.c
index 545069d..8e72a23 100644
--- a/drivers/cpuidle/cpuidle-arm.c
+++ b/drivers/cpuidle/cpuidle-arm.c
@@ -11,13 +11,16 @@ 
 
 #define pr_fmt(fmt) "CPUidle arm: " fmt
 
+#include <linux/cpu.h>
 #include <linux/cpuidle.h>
 #include <linux/cpumask.h>
 #include <linux/cpu_pm.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
+#include <linux/rcupdate.h>
 
 #include <asm/cpuidle.h>
 
@@ -45,6 +48,10 @@  static int arm_enter_idle_state(struct cpuidle_device *dev,
 
 	ret = cpu_pm_enter();
 	if (!ret) {
+		struct device *cpu_dev = get_cpu_device(dev->cpu);
+
+		RCU_NONIDLE(pm_runtime_put_sync_suspend(cpu_dev));
+
 		/*
 		 * Pass idle state index to cpu_suspend which in turn will
 		 * call the CPU ops suspend protocol with idle index as a
@@ -52,6 +59,7 @@  static int arm_enter_idle_state(struct cpuidle_device *dev,
 		 */
 		arm_cpuidle_suspend(idx);
 
+		RCU_NONIDLE(pm_runtime_get_sync(cpu_dev));
 		cpu_pm_exit();
 	}