Some of the checks which may force tick_do_broadcast_on_off() to return early
can be done before taking locks. This would make these codepaths faster.

Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
---
 kernel/time/tick-broadcast.c | 20 +++++++-------------
 1 file changed, 7 insertions(+), 13 deletions(-)

diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 1597d03..3b07569 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -329,27 +329,22 @@ unlock:
  */
 static void tick_do_broadcast_on_off(unsigned long *reason)
 {
-       struct clock_event_device *bc, *dev;
-       struct tick_device *td;
+       struct tick_device *td = tick_get_cpu_device();
+       struct clock_event_device *bc, *dev = td->evtdev;
+       int cpu = smp_processor_id(), bc_stopped;
        unsigned long flags;
-       int cpu, bc_stopped;
-
-       raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
-
-       cpu = smp_processor_id();
-       td = tick_get_device(cpu);
-       dev = td->evtdev;
-       bc = tick_broadcast_device.evtdev;
 
        /*
         * Is the device not affected by the powerstate ?
         */
        if (!dev || !(dev->features & CLOCK_EVT_FEAT_C3STOP))
-               goto out;
+               return;
 
        if (!tick_device_is_functional(dev))
-               goto out;
+               return;
 
+       raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
+       bc = tick_broadcast_device.evtdev;
        bc_stopped = cpumask_empty(tick_broadcast_mask);
 
        switch (*reason) {
@@ -385,7 +380,6 @@ static void tick_do_broadcast_on_off(unsigned long *reason)
                else
                        tick_broadcast_setup_oneshot(bc);
        }
-out:
        raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
 }
 
-- 
1.7.12.rc2.18.g61b472e

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