korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-13 14:24:11 +08:00
Code Issues Packages Projects Releases Wiki Activity

cpuidle: prepare the cpuidle core to handle multiple drivers

Browse Source 
This patch is a preparation for the multiple cpuidle drivers support.

As the next patch will introduce the multiple drivers with the Kconfig
option and we want to keep the code clean and understandable, this patch
defines a set of functions for encapsulating some common parts and splits
what should be done under a lock from the rest.

[rjw: Modified the subject and changelog slightly.]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Daniel Lezcano 2012-10-31 16:44:47 +00:00 committed by Rafael J. Wysocki
parent 4168203271
commit 13dd52f11a
1 changed files with 44 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

64
drivers/cpuidle/driver.c
View File

@ -39,11 +39,20 @@ static void set_power_states(struct cpuidle_driver *drv)
drv->states[i].power_usage = -1 - i;
}
/**
* cpuidle_register_driver - registers a driver
* @drv: the driver
*/
int cpuidle_register_driver(struct cpuidle_driver *drv)
static void __cpuidle_driver_init(struct cpuidle_driver *drv)
{
drv->refcnt = 0;
if (!drv->power_specified)
set_power_states(drv);
}
static void cpuidle_set_driver(struct cpuidle_driver *drv)
{
cpuidle_curr_driver = drv;
}
static int __cpuidle_register_driver(struct cpuidle_driver *drv)
{
if (!drv || !drv->state_count)
return -EINVAL;
@ -51,23 +60,39 @@ int cpuidle_register_driver(struct cpuidle_driver *drv)
if (cpuidle_disabled())
return -ENODEV;
spin_lock(&cpuidle_driver_lock);
if (cpuidle_curr_driver) {
spin_unlock(&cpuidle_driver_lock);
if (cpuidle_get_driver())
return -EBUSY;
}
if (!drv->power_specified)
set_power_states(drv);
__cpuidle_driver_init(drv);
drv->refcnt = 0;
cpuidle_curr_driver = drv;
spin_unlock(&cpuidle_driver_lock);
cpuidle_set_driver(drv);
return 0;
}
static void __cpuidle_unregister_driver(struct cpuidle_driver *drv)
{
if (drv != cpuidle_get_driver())
return;
if (!WARN_ON(drv->refcnt > 0))
cpuidle_set_driver(NULL);
}
/**
* cpuidle_register_driver - registers a driver
* @drv: the driver
*/
int cpuidle_register_driver(struct cpuidle_driver *drv)
{
int ret;
spin_lock(&cpuidle_driver_lock);
ret = __cpuidle_register_driver(drv);
spin_unlock(&cpuidle_driver_lock);
return ret;
}
EXPORT_SYMBOL_GPL(cpuidle_register_driver);
/**
@ -86,8 +111,7 @@ EXPORT_SYMBOL_GPL(cpuidle_get_driver);
void cpuidle_unregister_driver(struct cpuidle_driver *drv)
{
spin_lock(&cpuidle_driver_lock);
if (drv == cpuidle_curr_driver && !WARN_ON(drv->refcnt > 0))
cpuidle_curr_driver = NULL;
__cpuidle_unregister_driver(drv);
spin_unlock(&cpuidle_driver_lock);
}
EXPORT_SYMBOL_GPL(cpuidle_unregister_driver);
@ -98,7 +122,7 @@ struct cpuidle_driver *cpuidle_driver_ref(void)
spin_lock(&cpuidle_driver_lock);
drv = cpuidle_curr_driver;
drv = cpuidle_get_driver();
drv->refcnt++;
spin_unlock(&cpuidle_driver_lock);
@ -107,7 +131,7 @@ struct cpuidle_driver *cpuidle_driver_ref(void)
void cpuidle_driver_unref(void)
{
struct cpuidle_driver *drv = cpuidle_curr_driver;
struct cpuidle_driver *drv = cpuidle_get_driver();
spin_lock(&cpuidle_driver_lock);