[PATCH 3/3] cpuidle: Using the wake_up_all_cpus() to wake up all idle cpus

From: Chuansheng Liu
Date: Mon Aug 18 2014 - 04:52:42 EST


Currently kick_all_cpus_sync() or smp_call_function() can not
break the polling idle cpu immediately.

Here using wake_up_all_cpus() which can wake up the polling idle
cpu quickly is much helpful for power.

Signed-off-by: Chuansheng Liu <chuansheng.liu@xxxxxxxxx>
---
drivers/cpuidle/cpuidle.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index ee9df5e..56d5c4d 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -223,7 +223,7 @@ void cpuidle_uninstall_idle_handler(void)
{
if (enabled_devices) {
initialized = 0;
- kick_all_cpus_sync();
+ wake_up_all_cpus();
}
}

@@ -530,11 +530,6 @@ EXPORT_SYMBOL_GPL(cpuidle_register);

#ifdef CONFIG_SMP

-static void smp_callback(void *v)
-{
- /* we already woke the CPU up, nothing more to do */
-}
-
/*
* This function gets called when a part of the kernel has a new latency
* requirement. This means we need to get all processors out of their C-state,
@@ -544,7 +539,7 @@ static void smp_callback(void *v)
static int cpuidle_latency_notify(struct notifier_block *b,
unsigned long l, void *v)
{
- smp_call_function(smp_callback, NULL, 1);
+ wake_up_all_cpus();
return NOTIFY_OK;
}

--
1.7.9.5

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