Index: head/share/man/man9/refcount.9
===================================================================
--- head/share/man/man9/refcount.9
+++ head/share/man/man9/refcount.9
@@ -26,7 +26,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd January 20, 2009
+.Dd July 21, 2019
 .Dt REFCOUNT 9
 .Os
 .Sh NAME
@@ -42,7 +42,7 @@
 .Fn refcount_init "volatile u_int *count" "u_int value"
 .Ft void
 .Fn refcount_acquire "volatile u_int *count"
-.Ft int
+.Ft bool
 .Fn refcount_release "volatile u_int *count"
 .Sh DESCRIPTION
 The
@@ -73,9 +73,9 @@
 The
 .Fn refcount_release
 function is used to release an existing reference.
-The function returns a non-zero value if the reference being released was
+The function returns true if the reference being released was
 the last reference;
-otherwise, it returns zero.
+otherwise, it returns false.
 .Pp
 Note that these routines do not provide any inter-CPU synchronization,
 data protection,
@@ -89,7 +89,7 @@
 .Sh RETURN VALUES
 The
 .Nm refcount_release
-function returns non-zero when releasing the last reference and zero when
+function returns true when releasing the last reference and false when
 releasing any other reference.
 .Sh HISTORY
 These functions were introduced in
Index: head/sys/sys/refcount.h
===================================================================
--- head/sys/sys/refcount.h
+++ head/sys/sys/refcount.h
@@ -69,7 +69,7 @@
 	}
 }
 
-static __inline int
+static __inline bool
 refcount_release(volatile u_int *count)
 {
 	u_int old;
@@ -78,7 +78,7 @@
 	old = atomic_fetchadd_int(count, -1);
 	KASSERT(old > 0, ("refcount %p is zero", count));
 	if (old > 1)
-		return (0);
+		return (false);
 
 	/*
 	 * Last reference.  Signal the user to call the destructor.
@@ -87,14 +87,14 @@
 	 * at the start of the function synchronized with this fence.
 	 */
 	atomic_thread_fence_acq();
-	return (1);
+	return (true);
 }
 
 /*
  * This functions returns non-zero if the refcount was
  * incremented. Else zero is returned.
  */
-static __inline __result_use_check int
+static __inline __result_use_check bool
 refcount_acquire_if_not_zero(volatile u_int *count)
 {
 	u_int old;
@@ -103,13 +103,13 @@
 	for (;;) {
 		KASSERT(old < UINT_MAX, ("refcount %p overflowed", count));
 		if (old == 0)
-			return (0);
+			return (false);
 		if (atomic_fcmpset_int(count, &old, old + 1))
-			return (1);
+			return (true);
 	}
 }
 
-static __inline __result_use_check int
+static __inline __result_use_check bool
 refcount_release_if_not_last(volatile u_int *count)
 {
 	u_int old;
@@ -118,9 +118,9 @@
 	for (;;) {
 		KASSERT(old > 0, ("refcount %p is zero", count));
 		if (old == 1)
-			return (0);
+			return (false);
 		if (atomic_fcmpset_int(count, &old, old - 1))
-			return (1);
+			return (true);
 	}
 }