rangetimers: fix the bug reported by Ingo for real

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

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 01483004183d968909ea4743a294368de77eeadd..2bd230be1cb5ae3a778546d2ed0e651e153ba46e 100644 (file)
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -945,9 +945,10 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base)
 }
 
 /**
- * hrtimer_start - (re)start an relative timer on the current CPU
+ * hrtimer_start_range_ns - (re)start an relative timer on the current CPU
  * @timer:     the timer to be added
  * @tim:       expiry time
+ * @delta_ns:  "slack" range for the timer
  * @mode:      expiry mode: absolute (HRTIMER_ABS) or relative (HRTIMER_REL)
  *
  * Returns:
@@ -955,7 +956,8 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base)
  *  1 when the timer was active
  */
 int
-hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
+hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim, unsigned long delta_ns,
+                       const enum hrtimer_mode mode)
 {
        struct hrtimer_clock_base *base, *new_base;
        unsigned long flags;
@@ -983,7 +985,7 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
 #endif
        }
 
-       hrtimer_set_expires(timer, tim);
+       hrtimer_set_expires_range_ns(timer, tim, delta_ns);
 
        timer_stats_hrtimer_set_start_info(timer);
 
@@ -1016,8 +1018,26 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
 
        return ret;
 }
+EXPORT_SYMBOL_GPL(hrtimer_start_range_ns);
+
+/**
+ * hrtimer_start - (re)start an relative timer on the current CPU
+ * @timer:     the timer to be added
+ * @tim:       expiry time
+ * @mode:      expiry mode: absolute (HRTIMER_ABS) or relative (HRTIMER_REL)
+ *
+ * Returns:
+ *  0 on success
+ *  1 when the timer was active
+ */
+int
+hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
+{
+       return hrtimer_start_range_ns(timer, tim, 0, mode);
+}
 EXPORT_SYMBOL_GPL(hrtimer_start);
 
+
 /**
  * hrtimer_try_to_cancel - try to deactivate a timer
  * @timer:     hrtimer to stop
@@ -1361,6 +1381,36 @@ void hrtimer_interrupt(struct clock_event_device *dev)
                raise_softirq(HRTIMER_SOFTIRQ);
 }
 
+/**
+ * hrtimer_peek_ahead_timers -- run soft-expired timers now
+ *
+ * hrtimer_peek_ahead_timers will peek at the timer queue of
+ * the current cpu and check if there are any timers for which
+ * the soft expires time has passed. If any such timers exist,
+ * they are run immediately and then removed from the timer queue.
+ *
+ */
+void hrtimer_peek_ahead_timers(void)
+{
+       unsigned long flags;
+       struct tick_device *td;
+       struct clock_event_device *dev;
+
+       if (!hrtimer_hres_active())
+               return;
+
+       local_irq_save(flags);
+       td = &__get_cpu_var(tick_cpu_device);
+       if (!td)
+               goto out;
+       dev = td->evtdev;
+       if (!dev)
+               goto out;
+       hrtimer_interrupt(dev);
+out:
+       local_irq_restore(flags);
+}
+
 static void run_hrtimer_softirq(struct softirq_action *h)
 {
        run_hrtimer_pending(&__get_cpu_var(hrtimer_bases));
@@ -1543,9 +1593,14 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
        struct restart_block *restart;
        struct hrtimer_sleeper t;
        int ret = 0;
+       unsigned long slack;
+
+       slack = current->timer_slack_ns;
+       if (rt_task(current))
+               slack = 0;
 
        hrtimer_init_on_stack(&t.timer, clockid, mode);
-       hrtimer_set_expires(&t.timer, timespec_to_ktime(*rqtp));
+       hrtimer_set_expires_range_ns(&t.timer, timespec_to_ktime(*rqtp), slack);
        if (do_nanosleep(&t, mode))
                goto out;