Add instrumentation for timer_mod to allow measurement of the
average time delta to expiry plus the number of short delta
periods. This is only run when logging to a file because
getting the clock value may add appreciable expense.
Signed-off-by: Alex Bligh <a...@alex.org.uk>
---
qemu-timer.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/qemu-timer.c b/qemu-timer.c
index 84a8932..16eaa1f 100644
--- a/qemu-timer.c
+++ b/qemu-timer.c
@@ -376,6 +376,23 @@ static bool timer_mod_ns_locked(QEMUTimerList *timer_list,
ts->next = *pt;
*pt = ts;
+ if (timer_debug_log) {
+ int64_t delta;
+
+ delta = ts->expire_time -
+ qemu_clock_get_ns(ts->timer_list->clock->type);
+ if (delta <= 0) {
+ delta = 0;
+ }
+
+ ts->tot_deltas += delta;
+ ts->num_deltas++;
+
+ if (delta < SCALE_US) {
+ ts->num_short++;
+ }
+ }
+
return pt == &timer_list->active_timers;
}
--
1.7.9.5
