[kernel] sync with external source. support for dynamic timer
Change-Id: I87d3c87a7a046413975108f93be63fa5a5999636
diff --git a/kernel/timer.c b/kernel/timer.c
index 71bc4fb..c041d49 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2008 Travis Geiselbrecht
+ * Copyright (c) 2008-2009 Travis Geiselbrecht
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files
@@ -29,6 +29,8 @@
static struct list_node timer_queue;
+static enum handler_return timer_tick(void *arg, time_t now);
+
void timer_initialize(timer_t *timer)
{
timer->magic = TIMER_MAGIC;
@@ -43,8 +45,10 @@
{
timer_t *entry;
+// TRACEF("timer %p, scheduled %d, periodic %d\n", timer, timer->scheduled_time, timer->periodic_time);
+
list_for_every_entry(&timer_queue, entry, timer_t, node) {
- if (entry->scheduled_time > timer->scheduled_time) {
+ if (TIME_GT(entry->scheduled_time, timer->scheduled_time)) {
list_add_before(&entry->node, &timer->node);
return;
}
@@ -54,11 +58,11 @@
list_add_tail(&timer_queue, &timer->node);
}
-void timer_set_oneshot(timer_t *timer, time_t delay, timer_callback callback, void *arg)
+static void timer_set(timer_t *timer, time_t delay, time_t period, timer_callback callback, void *arg)
{
time_t now;
-// TRACEF("delay %d, callback %p, arg %p\n", delay, callback, arg);
+// TRACEF("timer %p, delay %d, period %d, callback %p, arg %p, now %d\n", timer, delay, period, callback, arg);
DEBUG_ASSERT(timer->magic == TIMER_MAGIC);
@@ -68,7 +72,7 @@
now = current_time();
timer->scheduled_time = now + delay;
- timer->periodic_time = 0;
+ timer->periodic_time = period;
timer->callback = callback;
timer->arg = arg;
@@ -78,18 +82,71 @@
insert_timer_in_queue(timer);
+#if PLATFORM_HAS_DYNAMIC_TIMER
+ if (list_peek_head_type(&timer_queue, timer_t, node) == timer) {
+ /* we just modified the head of the timer queue */
+// TRACEF("setting new timer for %u msecs\n", (uint)delay);
+ platform_set_oneshot_timer(timer_tick, NULL, delay);
+ }
+#endif
+
exit_critical_section();
}
+void timer_set_oneshot(timer_t *timer, time_t delay, timer_callback callback, void *arg)
+{
+ if (delay == 0)
+ delay = 1;
+ timer_set(timer, delay, 0, callback, arg);
+}
+
+void timer_set_periodic(timer_t *timer, time_t period, timer_callback callback, void *arg)
+{
+ if (period == 0)
+ period = 1;
+ timer_set(timer, period, period, callback, arg);
+}
+
void timer_cancel(timer_t *timer)
{
DEBUG_ASSERT(timer->magic == TIMER_MAGIC);
enter_critical_section();
+#if PLATFORM_HAS_DYNAMIC_TIMER
+ timer_t *oldhead = list_peek_head_type(&timer_queue, timer_t, node);
+#endif
+
if (list_in_list(&timer->node))
list_delete(&timer->node);
+ /* to keep it from being reinserted into the queue if called from
+ * periodic timer callback.
+ */
+ timer->periodic_time = 0;
+ timer->callback = NULL;
+ timer->arg = NULL;
+
+#if PLATFORM_HAS_DYNAMIC_TIMER
+ /* see if we've just modified the head of the timer queue */
+ timer_t *newhead = list_peek_head_type(&timer_queue, timer_t, node);
+ if (newhead == NULL) {
+// TRACEF("clearing old hw timer, nothing in the queue\n");
+ platform_stop_timer();
+ } else if (newhead != oldhead) {
+ time_t delay;
+ time_t now = current_time();
+
+ if (TIME_LT(newhead->scheduled_time, now))
+ delay = 0;
+ else
+ delay = newhead->scheduled_time - now;
+
+// TRACEF("setting new timer to %d\n", delay);
+ platform_set_oneshot_timer(timer_tick, NULL, delay);
+ }
+#endif
+
exit_critical_section();
}
@@ -103,10 +160,12 @@
thread_stats.timer_ints++;
#endif
+// TRACEF("now %d\n", now);
+
for (;;) {
/* see if there's an event to process */
timer = list_peek_head_type(&timer_queue, timer_t, node);
- if (likely(!timer || now < timer->scheduled_time))
+ if (likely(!timer || TIME_LT(now, timer->scheduled_time)))
break;
/* process it */
@@ -115,19 +174,48 @@
// timer = list_remove_head_type(&timer_queue, timer_t, node);
// ASSERT(timer);
+// TRACEF("dequeued timer %p, scheduled %d periodic %d\n", timer, timer->scheduled_time, timer->periodic_time);
+
#if THREAD_STATS
thread_stats.timers++;
#endif
-// TRACEF("firing callback %p, arg %p\n", timer->callback, timer->arg);
+ bool periodic = timer->periodic_time > 0;
+
+// TRACEF("timer %p firing callback %p, arg %p\n", timer, timer->callback, timer->arg);
if (timer->callback(timer, now, timer->arg) == INT_RESCHEDULE)
ret = INT_RESCHEDULE;
+
+ /* if it was a periodic timer and it hasn't been requeued
+ * by the callback put it back in the list
+ */
+ if (periodic && !list_in_list(&timer->node) && timer->periodic_time > 0) {
+// TRACEF("periodic timer, period %u\n", (uint)timer->periodic_time);
+ timer->scheduled_time = now + timer->periodic_time;
+ insert_timer_in_queue(timer);
+ }
}
+#if PLATFORM_HAS_DYNAMIC_TIMER
+ /* reset the timer to the next event */
+ timer = list_peek_head_type(&timer_queue, timer_t, node);
+ if (timer) {
+ /* has to be the case or it would have fired already */
+ ASSERT(TIME_GT(timer->scheduled_time, now));
+
+ time_t delay = timer->scheduled_time - now;
+
+// TRACEF("setting new timer for %u msecs for event %p\n", (uint)delay, timer);
+ platform_set_oneshot_timer(timer_tick, NULL, delay);
+ }
+#else
/* let the scheduler have a shot to do quantum expiration, etc */
+ /* in case of dynamic timer, the scheduler will set up a periodic timer */
if (thread_timer_tick() == INT_RESCHEDULE)
ret = INT_RESCHEDULE;
+#endif
+ // XXX fix this, should return ret
return INT_RESCHEDULE;
}