[PATCH] fix next_timer_interrupt() for hrtimer

[linux-2.6-omap-h63xx.git] / kernel / hrtimer.c

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 5ae51f1bc7c80347d091bd4da0df2e8840c0bae4..14bc9cfa63999eee7fa1b25e4129ee67463e53bc 100644 (file)
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -505,6 +505,41 @@ ktime_t hrtimer_get_remaining(const struct hrtimer *timer)
        return rem;
 }
 
+#ifdef CONFIG_NO_IDLE_HZ
+/**
+ * hrtimer_get_next_event - get the time until next expiry event
+ *
+ * Returns the delta to the next expiry event or KTIME_MAX if no timer
+ * is pending.
+ */
+ktime_t hrtimer_get_next_event(void)
+{
+       struct hrtimer_base *base = __get_cpu_var(hrtimer_bases);
+       ktime_t delta, mindelta = { .tv64 = KTIME_MAX };
+       unsigned long flags;
+       int i;
+
+       for (i = 0; i < MAX_HRTIMER_BASES; i++, base++) {
+               struct hrtimer *timer;
+
+               spin_lock_irqsave(&base->lock, flags);
+               if (!base->first) {
+                       spin_unlock_irqrestore(&base->lock, flags);
+                       continue;
+               }
+               timer = rb_entry(base->first, struct hrtimer, node);
+               delta.tv64 = timer->expires.tv64;
+               spin_unlock_irqrestore(&base->lock, flags);
+               delta = ktime_sub(delta, base->get_time());
+               if (delta.tv64 < mindelta.tv64)
+                       mindelta.tv64 = delta.tv64;
+       }
+       if (mindelta.tv64 < 0)
+               mindelta.tv64 = 0;
+       return mindelta;
+}
+#endif
+
 /**
  * hrtimer_init - initialize a timer to the given clock
  *