bitkeeper revision 1.14.1.1 (3e397e7cPGmZK7y5LLOGYa43nTQMUw)

added time and accurate timer support
partially there for better scheduler (most of the infrastructure should be there)

1 files changed, 8 insertions, 1 deletions

diff --git a/xen-2.4.16/include/xeno/timer.h b/xen-2.4.16/include/xeno/timer.h
index c4f01ada59..dcde75b182 100644
--- a/xen-2.4.16/include/xeno/timer.h
+++ b/xen-2.4.16/include/xeno/timer.h
@@ -12,10 +12,17 @@
  * The "data" field enables use of a common timeout function for several
  * timeouts. You can use this field to distinguish between the different
  * invocations.
+ *
+ * RN: Unlike the Linux timers, which are executed at the periodic timer
+ *     interrupt, in Xen, the timer list is only checked "occasionally", thus
+ *     its accuracy might be somewhat worse than under Linux. However, the
+ *     hypervisor should be purely event-driven and, in fact, in the current
+ *     implementation, timers are only used for watchdog purpose at a very
+ *     coarse granularity anyway. Thus this is not a problem.
  */
 struct timer_list {
 	struct list_head list;
-	unsigned long expires;
+	unsigned long expires;		/* jiffies */
 	unsigned long data;
 	void (*function)(unsigned long);
 };