diff --git a/sys/kern/kern_clocksource.c b/sys/kern/kern_clocksource.c
index eb20a4068503..455564b61979 100644
--- a/sys/kern/kern_clocksource.c
+++ b/sys/kern/kern_clocksource.c
@@ -117,7 +117,8 @@ SYSCTL_INT(_kern_eventtimer, OID_AUTO, idletick, CTLFLAG_RW, &idletick,
     0, "Run periodic events when idle");
 
 static int		periodic = 0;	/* Periodic or one-shot mode. */
-TUNABLE_INT("kern.eventtimer.periodic", &periodic);
+static int		want_periodic = 0; /* What mode to prefer. */
+TUNABLE_INT("kern.eventtimer.periodic", &want_periodic);
 
 struct pcpu_state {
 	struct mtx	et_hw_mtx;	/* Per-CPU timer mutex. */
@@ -587,6 +588,7 @@ cpu_initclocks_bsp(void)
 #ifdef SMP
 	callout_new_inserted = cpu_new_callout;
 #endif
+	periodic = want_periodic;
 	/* Grab requested timer or the best of present. */
 	if (timername[0])
 		timer = et_find(timername, 0, 0);
@@ -841,6 +843,7 @@ sysctl_kern_eventtimer_timer(SYSCTL_HANDLER_ARGS)
 		cpu_disable_deep_sleep++;
 	if (timer->et_flags & ET_FLAGS_C3STOP)
 		cpu_disable_deep_sleep--;
+	periodic = want_periodic;
 	timer = et;
 	et_init(timer, timercb, NULL, NULL);
 	configtimer(1);
@@ -865,7 +868,7 @@ sysctl_kern_eventtimer_periodic(SYSCTL_HANDLER_ARGS)
 		return (error);
 	ET_LOCK();
 	configtimer(0);
-	periodic = val;
+	periodic = want_periodic = val;
 	configtimer(1);
 	ET_UNLOCK();
 	return (error);