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authorLen Brown <len.brown@intel.com>2011-04-01 19:34:59 -0400
committerLen Brown <len.brown@intel.com>2011-08-03 19:06:37 -0400
commita0bfa1373859e9d11dc92561a8667588803e42d8 (patch)
treeef5768a313ac16a211830efc3edb9ca95487cb6a /drivers/cpuidle/cpuidle.c
parent4bfc8288bc4a64529c5547d17349a2a1f4675507 (diff)
downloadlinux-linaro-stable-a0bfa1373859e9d11dc92561a8667588803e42d8.tar.gz
cpuidle: stop depending on pm_idle
cpuidle users should call cpuidle_call_idle() directly rather than via (pm_idle)() function pointer. Architecture may choose to continue using (pm_idle)(), but cpuidle need not depend on it: my_arch_cpu_idle() ... if(cpuidle_call_idle()) pm_idle(); cc: Kevin Hilman <khilman@deeprootsystems.com> cc: Paul Mundt <lethal@linux-sh.org> cc: x86@kernel.org Acked-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/cpuidle/cpuidle.c')
-rw-r--r--drivers/cpuidle/cpuidle.c38
1 files changed, 18 insertions, 20 deletions
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 041df0b056b2..d4c542372886 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -25,10 +25,10 @@ DEFINE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
DEFINE_MUTEX(cpuidle_lock);
LIST_HEAD(cpuidle_detected_devices);
-static void (*pm_idle_old)(void);
static int enabled_devices;
static int off __read_mostly;
+static int initialized __read_mostly;
int cpuidle_disabled(void)
{
@@ -56,25 +56,23 @@ static int __cpuidle_register_device(struct cpuidle_device *dev);
* cpuidle_idle_call - the main idle loop
*
* NOTE: no locks or semaphores should be used here
+ * return non-zero on failure
*/
-static void cpuidle_idle_call(void)
+int cpuidle_idle_call(void)
{
struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
struct cpuidle_state *target_state;
int next_state;
+ if (off)
+ return -ENODEV;
+
+ if (!initialized)
+ return -ENODEV;
+
/* check if the device is ready */
- if (!dev || !dev->enabled) {
- if (pm_idle_old)
- pm_idle_old();
- else
-#if defined(CONFIG_ARCH_HAS_DEFAULT_IDLE)
- default_idle();
-#else
- local_irq_enable();
-#endif
- return;
- }
+ if (!dev || !dev->enabled)
+ return -EBUSY;
#if 0
/* shows regressions, re-enable for 2.6.29 */
@@ -99,7 +97,7 @@ static void cpuidle_idle_call(void)
next_state = cpuidle_curr_governor->select(dev);
if (need_resched()) {
local_irq_enable();
- return;
+ return 0;
}
target_state = &dev->states[next_state];
@@ -124,6 +122,8 @@ static void cpuidle_idle_call(void)
/* give the governor an opportunity to reflect on the outcome */
if (cpuidle_curr_governor->reflect)
cpuidle_curr_governor->reflect(dev);
+
+ return 0;
}
/**
@@ -131,10 +131,10 @@ static void cpuidle_idle_call(void)
*/
void cpuidle_install_idle_handler(void)
{
- if (enabled_devices && (pm_idle != cpuidle_idle_call)) {
+ if (enabled_devices) {
/* Make sure all changes finished before we switch to new idle */
smp_wmb();
- pm_idle = cpuidle_idle_call;
+ initialized = 1;
}
}
@@ -143,8 +143,8 @@ void cpuidle_install_idle_handler(void)
*/
void cpuidle_uninstall_idle_handler(void)
{
- if (enabled_devices && pm_idle_old && (pm_idle != pm_idle_old)) {
- pm_idle = pm_idle_old;
+ if (enabled_devices) {
+ initialized = 0;
cpuidle_kick_cpus();
}
}
@@ -440,8 +440,6 @@ static int __init cpuidle_init(void)
if (cpuidle_disabled())
return -ENODEV;
- pm_idle_old = pm_idle;
-
ret = cpuidle_add_class_sysfs(&cpu_sysdev_class);
if (ret)
return ret;