diff --git a/head/sys/kern/kern_time.c b/head/sys/kern/kern_time.c
--- a/head/sys/kern/kern_time.c
+++ b/head/sys/kern/kern_time.c
@@ -256,11 +256,11 @@
 	uint64_t runtime, curtime, switchtime;
 
 	if (targettd == NULL) { /* current thread */
-		critical_enter();
+		spinlock_enter();
 		switchtime = PCPU_GET(switchtime);
 		curtime = cpu_ticks();
 		runtime = curthread->td_runtime;
-		critical_exit();
+		spinlock_exit();
 		runtime += curtime - switchtime;
 	} else {
 		PROC_LOCK_ASSERT(targettd->td_proc, MA_OWNED);