cpuidle: make cpuidle_curr_driver static

cpuidle_register_driver() sets cpuidle_curr_driver
cpuidle_unregister_driver() clears cpuidle_curr_driver

We should't expose cpuidle_curr_driver to
potential modification except via these interfaces.
So make it static and create cpuidle_get_driver() to observe it.

Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 12fdd39..1994885 100644 (file)
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -156,7 +156,7 @@ int cpuidle_enable_device(struct cpuidle_device *dev)
 
        if (dev->enabled)
                return 0;
-       if (!cpuidle_curr_driver || !cpuidle_curr_governor)
+       if (!cpuidle_get_driver() || !cpuidle_curr_governor)
                return -EIO;
        if (!dev->state_count)
                return -EINVAL;
@@ -207,7 +207,7 @@ void cpuidle_disable_device(struct cpuidle_device *dev)
 {
        if (!dev->enabled)
                return;
-       if (!cpuidle_curr_driver || !cpuidle_curr_governor)
+       if (!cpuidle_get_driver() || !cpuidle_curr_governor)
                return;
 
        dev->enabled = 0;
@@ -271,10 +271,11 @@ static int __cpuidle_register_device(struct cpuidle_device *dev)
 {
        int ret;
        struct sys_device *sys_dev = get_cpu_sysdev((unsigned long)dev->cpu);
+       struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();
 
        if (!sys_dev)
                return -EINVAL;
-       if (!try_module_get(cpuidle_curr_driver->owner))
+       if (!try_module_get(cpuidle_driver->owner))
                return -EINVAL;
 
        init_completion(&dev->kobj_unregister);
@@ -284,7 +285,7 @@ static int __cpuidle_register_device(struct cpuidle_device *dev)
        per_cpu(cpuidle_devices, dev->cpu) = dev;
        list_add(&dev->device_list, &cpuidle_detected_devices);
        if ((ret = cpuidle_add_sysfs(sys_dev))) {
-               module_put(cpuidle_curr_driver->owner);
+               module_put(cpuidle_driver->owner);
                return ret;
        }
 
@@ -325,6 +326,7 @@ EXPORT_SYMBOL_GPL(cpuidle_register_device);
 void cpuidle_unregister_device(struct cpuidle_device *dev)
 {
        struct sys_device *sys_dev = get_cpu_sysdev((unsigned long)dev->cpu);
+       struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();
 
        if (dev->registered == 0)
                return;
@@ -340,7 +342,7 @@ void cpuidle_unregister_device(struct cpuidle_device *dev)
 
        cpuidle_resume_and_unlock();
 
-       module_put(cpuidle_curr_driver->owner);
+       module_put(cpuidle_driver->owner);
 }
 
 EXPORT_SYMBOL_GPL(cpuidle_unregister_device);

diff --git a/drivers/cpuidle/cpuidle.h b/drivers/cpuidle/cpuidle.h
index 9476ba3..33e50d5 100644 (file)
--- a/drivers/cpuidle/cpuidle.h
+++ b/drivers/cpuidle/cpuidle.h
@@ -9,7 +9,6 @@
 
 /* For internal use only */
 extern struct cpuidle_governor *cpuidle_curr_governor;
-extern struct cpuidle_driver *cpuidle_curr_driver;
 extern struct list_head cpuidle_governors;
 extern struct list_head cpuidle_detected_devices;
 extern struct mutex cpuidle_lock;

diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 826b5c0..fd1601e 100644 (file)
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -14,7 +14,7 @@
 
 #include "cpuidle.h"
 
-struct cpuidle_driver *cpuidle_curr_driver;
+static struct cpuidle_driver *cpuidle_curr_driver;
 DEFINE_SPINLOCK(cpuidle_driver_lock);
 
 /**
@@ -39,6 +39,15 @@ int cpuidle_register_driver(struct cpuidle_driver *drv)
 
 EXPORT_SYMBOL_GPL(cpuidle_register_driver);
 
+/**
+ * cpuidle_get_driver - return the current driver
+ */
+struct cpuidle_driver *cpuidle_get_driver(void)
+{
+       return cpuidle_curr_driver;
+}
+EXPORT_SYMBOL_GPL(cpuidle_get_driver);
+
 /**
  * cpuidle_unregister_driver - unregisters a driver
  * @drv: the driver

diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c
index 0ba9c8b..0310ffa 100644 (file)
--- a/drivers/cpuidle/sysfs.c
+++ b/drivers/cpuidle/sysfs.c
@@ -47,10 +47,11 @@ static ssize_t show_current_driver(struct sysdev_class *class,
                                   char *buf)
 {
        ssize_t ret;
+       struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();
 
        spin_lock(&cpuidle_driver_lock);
-       if (cpuidle_curr_driver)
-               ret = sprintf(buf, "%s\n", cpuidle_curr_driver->name);
+       if (cpuidle_driver)
+               ret = sprintf(buf, "%s\n", cpuidle_driver->name);
        else
                ret = sprintf(buf, "none\n");
        spin_unlock(&cpuidle_driver_lock);

diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index f5e6480..55215cc 100644 (file)
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -125,6 +125,7 @@ struct cpuidle_driver {
 #ifdef CONFIG_CPU_IDLE
 
 extern int cpuidle_register_driver(struct cpuidle_driver *drv);
+struct cpuidle_driver *cpuidle_get_driver(void);
 extern void cpuidle_unregister_driver(struct cpuidle_driver *drv);
 extern int cpuidle_register_device(struct cpuidle_device *dev);
 extern void cpuidle_unregister_device(struct cpuidle_device *dev);
@@ -138,6 +139,7 @@ extern void cpuidle_disable_device(struct cpuidle_device *dev);
 
 static inline int cpuidle_register_driver(struct cpuidle_driver *drv)
 {return -ENODEV; }
+static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; }
 static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { }
 static inline int cpuidle_register_device(struct cpuidle_device *dev)
 {return -ENODEV; }