Merge branch 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel...

[pandora-kernel.git] / kernel / time / tick-sched.c

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 70f872c..76a574b 100644 (file)
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -247,7 +247,7 @@ void tick_nohz_stop_sched_tick(int inidle)
        if (need_resched())
                goto end;
 
-       if (unlikely(local_softirq_pending())) {
+       if (unlikely(local_softirq_pending() && cpu_online(cpu))) {
                static int ratelimit;
 
                if (ratelimit < 10) {
@@ -282,8 +282,31 @@ void tick_nohz_stop_sched_tick(int inidle)
        /* Schedule the tick, if we are at least one jiffie off */
        if ((long)delta_jiffies >= 1) {
 
+               /*
+               * calculate the expiry time for the next timer wheel
+               * timer
+               */
+               expires = ktime_add_ns(last_update, tick_period.tv64 *
+                                  delta_jiffies);
+
+               /*
+                * If this cpu is the one which updates jiffies, then
+                * give up the assignment and let it be taken by the
+                * cpu which runs the tick timer next, which might be
+                * this cpu as well. If we don't drop this here the
+                * jiffies might be stale and do_timer() never
+                * invoked.
+                */
+               if (cpu == tick_do_timer_cpu)
+                       tick_do_timer_cpu = TICK_DO_TIMER_NONE;
+
                if (delta_jiffies > 1)
                        cpumask_set_cpu(cpu, nohz_cpu_mask);
+
+               /* Skip reprogram of event if its not changed */
+               if (ts->tick_stopped && ktime_equal(expires, dev->next_event))
+                       goto out;
+
                /*
                 * nohz_stop_sched_tick can be called several times before
                 * the nohz_restart_sched_tick is called. This happens when
@@ -306,17 +329,6 @@ void tick_nohz_stop_sched_tick(int inidle)
                        rcu_enter_nohz();
                }
 
-               /*
-                * If this cpu is the one which updates jiffies, then
-                * give up the assignment and let it be taken by the
-                * cpu which runs the tick timer next, which might be
-                * this cpu as well. If we don't drop this here the
-                * jiffies might be stale and do_timer() never
-                * invoked.
-                */
-               if (cpu == tick_do_timer_cpu)
-                       tick_do_timer_cpu = TICK_DO_TIMER_NONE;
-
                ts->idle_sleeps++;
 
                /*
@@ -332,12 +344,7 @@ void tick_nohz_stop_sched_tick(int inidle)
                        goto out;
                }
 
-               /*
-                * calculate the expiry time for the next timer wheel
-                * timer
-                */
-               expires = ktime_add_ns(last_update, tick_period.tv64 *
-                                      delta_jiffies);
+               /* Mark expiries */
                ts->idle_expires = expires;
 
                if (ts->nohz_mode == NOHZ_MODE_HIGHRES) {
@@ -681,7 +688,6 @@ void tick_setup_sched_timer(void)
         */
        hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
        ts->sched_timer.function = tick_sched_timer;
-       ts->sched_timer.cb_mode = HRTIMER_CB_IRQSAFE_PERCPU;
 
        /* Get the next period (per cpu) */
        hrtimer_set_expires(&ts->sched_timer, tick_init_jiffy_update());