[02/15] cpuidle: initialize the broadcast timer framework

Message ID 1364234140-514-3-git-send-email-daniel.lezcano@linaro.org
State New
Headers show

Commit Message

Daniel Lezcano March 25, 2013, 5:55 p.m.
The commit 89878baa73f0f1c679355006bd8632e5d78f96c2 introduced
the CPUIDLE_FLAG_TIMER_STOP flag where we specify a specific idle
state stops the local timer.

Now use this flag to check at init time if one state will need
the broadcast timer and, in this case, setup the broadcast timer
framework. That prevents multiple code duplication in the drivers.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/cpuidle/driver.c |   35 +++++++++++++++++++++++++++++++++--
 include/linux/cpuidle.h  |    2 ++
 2 files changed, 35 insertions(+), 2 deletions(-)

Comments

Santosh Shilimkar March 26, 2013, 4:39 a.m. | #1
On Monday 25 March 2013 11:25 PM, Daniel Lezcano wrote:
> The commit 89878baa73f0f1c679355006bd8632e5d78f96c2 introduced
> the CPUIDLE_FLAG_TIMER_STOP flag where we specify a specific idle
> state stops the local timer.
> 
> Now use this flag to check at init time if one state will need
> the broadcast timer and, in this case, setup the broadcast timer
> framework. That prevents multiple code duplication in the drivers.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> ---
>  drivers/cpuidle/driver.c |   35 +++++++++++++++++++++++++++++++++--
>  include/linux/cpuidle.h  |    2 ++
>  2 files changed, 35 insertions(+), 2 deletions(-)
> 
Make sense. Minor comments.

> diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
> index 422c7b6..476ce0c 100644
> --- a/drivers/cpuidle/driver.c
> +++ b/drivers/cpuidle/driver.c
> @@ -11,6 +11,8 @@
>  #include <linux/mutex.h>
>  #include <linux/module.h>
>  #include <linux/cpuidle.h>
> +#include <linux/cpumask.h>
> +#include <linux/clockchips.h>
>  
>  #include "cpuidle.h"
>  
> @@ -19,9 +21,30 @@ DEFINE_SPINLOCK(cpuidle_driver_lock);
>  static void __cpuidle_set_cpu_driver(struct cpuidle_driver *drv, int cpu);
>  static struct cpuidle_driver * __cpuidle_get_cpu_driver(int cpu);
>  
> -static void __cpuidle_driver_init(struct cpuidle_driver *drv)
> +static void cpuidle_setup_broadcast_timer(void *arg)
>  {
> +	int cpu = smp_processor_id();
> +	clockevents_notify((long)(arg), &cpu);
> +}
> +
> +static void __cpuidle_driver_init(struct cpuidle_driver *drv, int cpu)
> +{
> +	int i;
> +
Un-necessary extra line..

>  	drv->refcnt = 0;
> +
> +	for (i = drv->state_count - 1; i >= 0 ; i--) {
> +
here as well
> +		if (!(drv->states[i].flags & CPUIDLE_FLAG_TIMER_STOP))
> +			continue;
> +
> +		drv->bctimer = 1;
> +
ditto
> +		on_each_cpu_mask(get_cpu_mask(cpu), cpuidle_setup_broadcast_timer,
> +				 (void *)CLOCK_EVT_NOTIFY_BROADCAST_ON, 1);
> +
ditto
> +		break;
> +	}
>  }
>  
>  static int __cpuidle_register_driver(struct cpuidle_driver *drv, int cpu)
> @@ -35,7 +58,7 @@ static int __cpuidle_register_driver(struct cpuidle_driver *drv, int cpu)
>  	if (__cpuidle_get_cpu_driver(cpu))
>  		return -EBUSY;
>  
> -	__cpuidle_driver_init(drv);
> +	__cpuidle_driver_init(drv, cpu);
>  
>  	__cpuidle_set_cpu_driver(drv, cpu);
>  
> @@ -49,6 +72,14 @@ static void __cpuidle_unregister_driver(struct cpuidle_driver *drv, int cpu)
>  
>  	if (!WARN_ON(drv->refcnt > 0))
>  		__cpuidle_set_cpu_driver(NULL, cpu);
> +
> +	if (drv->bctimer) {
> +
> +		drv->bctimer = 0;
> +
> +
no need of extra line here
		on_each_cpu_mask(get_cpu_mask(cpu), cpuidle_setup_broadcast_timer,
> +				 (void *)CLOCK_EVT_NOTIFY_BROADCAST_OFF, 1);
> +	}
>  }
>  
>  #ifdef CONFIG_CPU_IDLE_MULTIPLE_DRIVERS
> diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
> index a837b33..fc3e580 100644
> --- a/include/linux/cpuidle.h
> +++ b/include/linux/cpuidle.h
> @@ -107,6 +107,8 @@ struct cpuidle_driver {
>  
>  	/* set to 1 to use the core cpuidle time keeping (for all states). */
>  	unsigned int		en_core_tk_irqen:1;
> +        /* used by the cpuidle framework to setup the broadcast timer */
> +	unsigned int            bctimer:1;
>  	/* states array must be ordered in decreasing power consumption */
>  	struct cpuidle_state	states[CPUIDLE_STATE_MAX];
>  	int			state_count;
>

Patch

diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 422c7b6..476ce0c 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -11,6 +11,8 @@ 
 #include <linux/mutex.h>
 #include <linux/module.h>
 #include <linux/cpuidle.h>
+#include <linux/cpumask.h>
+#include <linux/clockchips.h>
 
 #include "cpuidle.h"
 
@@ -19,9 +21,30 @@  DEFINE_SPINLOCK(cpuidle_driver_lock);
 static void __cpuidle_set_cpu_driver(struct cpuidle_driver *drv, int cpu);
 static struct cpuidle_driver * __cpuidle_get_cpu_driver(int cpu);
 
-static void __cpuidle_driver_init(struct cpuidle_driver *drv)
+static void cpuidle_setup_broadcast_timer(void *arg)
 {
+	int cpu = smp_processor_id();
+	clockevents_notify((long)(arg), &cpu);
+}
+
+static void __cpuidle_driver_init(struct cpuidle_driver *drv, int cpu)
+{
+	int i;
+
 	drv->refcnt = 0;
+
+	for (i = drv->state_count - 1; i >= 0 ; i--) {
+
+		if (!(drv->states[i].flags & CPUIDLE_FLAG_TIMER_STOP))
+			continue;
+
+		drv->bctimer = 1;
+
+		on_each_cpu_mask(get_cpu_mask(cpu), cpuidle_setup_broadcast_timer,
+				 (void *)CLOCK_EVT_NOTIFY_BROADCAST_ON, 1);
+
+		break;
+	}
 }
 
 static int __cpuidle_register_driver(struct cpuidle_driver *drv, int cpu)
@@ -35,7 +58,7 @@  static int __cpuidle_register_driver(struct cpuidle_driver *drv, int cpu)
 	if (__cpuidle_get_cpu_driver(cpu))
 		return -EBUSY;
 
-	__cpuidle_driver_init(drv);
+	__cpuidle_driver_init(drv, cpu);
 
 	__cpuidle_set_cpu_driver(drv, cpu);
 
@@ -49,6 +72,14 @@  static void __cpuidle_unregister_driver(struct cpuidle_driver *drv, int cpu)
 
 	if (!WARN_ON(drv->refcnt > 0))
 		__cpuidle_set_cpu_driver(NULL, cpu);
+
+	if (drv->bctimer) {
+
+		drv->bctimer = 0;
+
+		on_each_cpu_mask(get_cpu_mask(cpu), cpuidle_setup_broadcast_timer,
+				 (void *)CLOCK_EVT_NOTIFY_BROADCAST_OFF, 1);
+	}
 }
 
 #ifdef CONFIG_CPU_IDLE_MULTIPLE_DRIVERS
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index a837b33..fc3e580 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -107,6 +107,8 @@  struct cpuidle_driver {
 
 	/* set to 1 to use the core cpuidle time keeping (for all states). */
 	unsigned int		en_core_tk_irqen:1;
+        /* used by the cpuidle framework to setup the broadcast timer */
+	unsigned int            bctimer:1;
 	/* states array must be ordered in decreasing power consumption */
 	struct cpuidle_state	states[CPUIDLE_STATE_MAX];
 	int			state_count;