cpuidle: Use wake_up_all_idle_cpus() to wake up all idle cpus
authorChuansheng Liu <chuansheng.liu@intel.com>
Thu, 4 Sep 2014 07:17:55 +0000 (15:17 +0800)
committerIngo Molnar <mingo@kernel.org>
Fri, 19 Sep 2014 10:35:16 +0000 (12:35 +0200)
Currently kick_all_cpus_sync() or smp_call_function() can not
break the polling idle cpu immediately.

Instead using wake_up_all_idle_cpus() which can wake up the polling idle
cpu quickly is much more helpful for power.

Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-pm@vger.kernel.org
Cc: changcheng.liu@intel.com
Cc: xiaoming.wang@intel.com
Cc: souvik.k.chakravarty@intel.com
Cc: luto@amacapital.net
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: linux-pm@vger.kernel.org
Link: http://lkml.kernel.org/r/1409815075-4180-3-git-send-email-chuansheng.liu@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
drivers/cpuidle/cpuidle.c

index ee9df5e3f5eba2a5bb705e8be1898c2a370ccd21..d31e04ca8703508717ae0f99c89e104a743a46ec 100644 (file)
@@ -223,7 +223,7 @@ void cpuidle_uninstall_idle_handler(void)
 {
        if (enabled_devices) {
                initialized = 0;
-               kick_all_cpus_sync();
+               wake_up_all_idle_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_idle_cpus();
        return NOTIFY_OK;
 }