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Subject[099/129] intel_idle: fix API misuse
3.2-stable review patch.  If anyone has any objections, please let me know.

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Content-Length: 1839
Lines: 50

From: Shaohua Li <shaohua.li@intel.com>

commit 39a74fdedd1c1461d6fb6d330b5266886513c98f upstream.

smp_call_function() only lets all other CPUs execute a specific function,
while we expect all CPUs do in intel_idle. Without the fix, we could have
one cpu which has auto_demotion enabled or has no broadcast timer setup.
Usually we don't see impact because auto demotion just harms power and the
intel_idle init is called in CPU 0, where boradcast timer delivers
interrupt, but this still could be a problem.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/idle/intel_idle.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -395,7 +395,7 @@ static int intel_idle_probe(void)
if (boot_cpu_has(X86_FEATURE_ARAT)) /* Always Reliable APIC Timer */
lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE;
else {
- smp_call_function(__setup_broadcast_timer, (void *)true, 1);
+ on_each_cpu(__setup_broadcast_timer, (void *)true, 1);
register_cpu_notifier(&setup_broadcast_notifier);
}

@@ -472,7 +472,7 @@ static int intel_idle_cpuidle_driver_ini
}

if (auto_demotion_disable_flags)
- smp_call_function(auto_demotion_disable, NULL, 1);
+ on_each_cpu(auto_demotion_disable, NULL, 1);

return 0;
}
@@ -569,7 +569,7 @@ static void __exit intel_idle_exit(void)
cpuidle_unregister_driver(&intel_idle_driver);

if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) {
- smp_call_function(__setup_broadcast_timer, (void *)false, 1);
+ on_each_cpu(__setup_broadcast_timer, (void *)false, 1);
unregister_cpu_notifier(&setup_broadcast_notifier);
}




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