unsigned long ticks = 0;
ktime_t delta;
+ /*
+ * Do a quick check without holding xtime_lock:
+ */
+ delta = ktime_sub(now, last_jiffies_update);
+ if (delta.tv64 < tick_period.tv64)
+ return;
+
/* Reevalute with xtime_lock held */
write_seqlock(&xtime_lock);
}
}
-static ktime_t tick_nohz_start_idle(int cpu)
+static ktime_t tick_nohz_start_idle(struct tick_sched *ts)
{
- struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
ktime_t now, delta;
now = ktime_get();
* Called either from the idle loop or from irq_exit() when an idle period was
* just interrupted by an interrupt which did not cause a reschedule.
*/
-void tick_nohz_stop_sched_tick(void)
+void tick_nohz_stop_sched_tick(int inidle)
{
unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags;
- unsigned long rt_jiffies;
struct tick_sched *ts;
ktime_t last_update, expires, now;
struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev;
local_irq_save(flags);
cpu = smp_processor_id();
- now = tick_nohz_start_idle(cpu);
ts = &per_cpu(tick_cpu_sched, cpu);
+ now = tick_nohz_start_idle(ts);
/*
* If this cpu is offline and it is the one which updates
if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
goto end;
+ if (!inidle && !ts->inidle)
+ goto end;
+
+ ts->inidle = 1;
+
if (need_resched())
goto end;
- cpu = smp_processor_id();
if (unlikely(local_softirq_pending())) {
static int ratelimit;
local_softirq_pending());
ratelimit++;
}
+ goto end;
}
ts->idle_calls++;
next_jiffies = get_next_timer_interrupt(last_jiffies);
delta_jiffies = next_jiffies - last_jiffies;
- rt_jiffies = rt_needs_cpu(cpu);
- if (rt_jiffies && rt_jiffies < delta_jiffies)
- delta_jiffies = rt_jiffies;
-
if (rcu_needs_cpu(cpu))
delta_jiffies = 1;
/*
local_irq_disable();
tick_nohz_stop_idle(cpu);
- if (!ts->tick_stopped) {
+ if (!ts->inidle || !ts->tick_stopped) {
+ ts->inidle = 0;
local_irq_enable();
return;
}
+ ts->inidle = 0;
+
rcu_exit_nohz();
/* Update jiffies first */
sub_preempt_count(HARDIRQ_OFFSET);
}
+ touch_softlockup_watchdog();
/*
* Cancel the scheduled timer and restore the tick
*/