[kernel] sync with external source. support for dynamic timer

include/kernel/timer.h

@@ -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

include/sys/types.h

@@ -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
@@ -60,6 +60,11 @@ typedef unsigned long time_t;
 typedef unsigned long long bigtime_t;
 #define INFINITE_TIME ULONG_MAX
 
+#define TIME_GTE(a, b) ((long)((a) - (b)) >= 0)
+#define TIME_LTE(a, b) ((long)((a) - (b)) <= 0)
+#define TIME_GT(a, b) ((long)((a) - (b)) > 0)
+#define TIME_LT(a, b) ((long)((a) - (b)) < 0)
+
 enum handler_return {
 	INT_NO_RESCHEDULE = 0,
 	INT_RESCHEDULE,

kernel/debug.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
@@ -26,7 +26,7 @@
 #include <kernel/timer.h>
 #include <platform.h>
 
-#if defined(WITH_LIB_CONSOLE)
+#if WITH_LIB_CONSOLE
 #include <lib/console.h>
 
 static int cmd_threads(int argc, const cmd_args *argv);
@@ -35,11 +35,11 @@ static int cmd_threadload(int argc, const cmd_args *argv);
 
 STATIC_COMMAND_START
 #if DEBUGLEVEL > 1
-	{ "threads", "list kernel threads", &cmd_threads },
+STATIC_COMMAND("threads", "list kernel threads", &cmd_threads)
 #endif
 #if THREAD_STATS
-	{ "threadstats", "thread level statistics", &cmd_threadstats },
-	{ "threadload", "toggle thread load display", &cmd_threadload },
+STATIC_COMMAND("threadstats", "thread level statistics", &cmd_threadstats)
+STATIC_COMMAND("threadload", "toggle thread load display", &cmd_threadload)
 #endif
 STATIC_COMMAND_END(kernel);
 
@@ -75,8 +75,6 @@ static enum handler_return threadload(struct timer *t, time_t now, void *arg)
 	static struct thread_stats old_stats;
 	static bigtime_t last_idle_time;
 
-	timer_set_oneshot(t, 1000, &threadload, NULL);
-
 	bigtime_t idle_time = thread_stats.idle_time;
 	if (current_thread == idle_thread) {
 		idle_time += current_time_hires() - thread_stats.last_idle_timestamp;
@@ -108,7 +106,7 @@ static int cmd_threadload(int argc, const cmd_args *argv)
 	if (showthreadload == false) {
 		// start the display
 		timer_initialize(&tltimer);
-		timer_set_oneshot(&tltimer, 1000, &threadload, NULL);
+		timer_set_periodic(&tltimer, 1000, &threadload, NULL);
 		showthreadload = true;
 	} else {
 		timer_cancel(&tltimer);

kernel/event.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

kernel/mutex.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
@@ -49,9 +49,9 @@ void mutex_destroy(mutex_t *m)
 	ASSERT(m->magic == MUTEX_MAGIC);
 #endif
 
-	if (m->holder != 0 && current_thread != m->holder)
-		panic("mutex_destroy: thread %p (%s) tried to release mutex %p it doesn't own. owned by %p (%s)\n", 
-				current_thread, current_thread->name, m, m->holder, m->holder ? m->holder->name : "none");
+//	if (m->holder != 0 && current_thread != m->holder)
+//		panic("mutex_destroy: thread %p (%s) tried to release mutex %p it doesn't own. owned by %p (%s)\n", 
+//				current_thread, current_thread->name, m, m->holder, m->holder ? m->holder->name : "none");
 
 	m->magic = 0;
 	m->count = 0;

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 @@ static void insert_timer_in_queue(timer_t *timer)
 {
 	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 @@ static void insert_timer_in_queue(timer_t *timer)
 	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 @@ void timer_set_oneshot(timer_t *timer, time_t delay, timer_callback callback, vo
 
 	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 @@ void timer_set_oneshot(timer_t *timer, time_t delay, timer_callback callback, vo
 
 	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 @@ static enum handler_return timer_tick(void *arg, time_t now)
 	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 @@ static enum handler_return timer_tick(void *arg, time_t now)
 //		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;
 }