diff --git a/sys/kern/kern_rmlock.c b/sys/kern/kern_rmlock.c
index db6e08e05198..af593a862d35 100644
--- a/sys/kern/kern_rmlock.c
+++ b/sys/kern/kern_rmlock.c
@@ -934,6 +934,30 @@ rms_rlock(struct rmslock *rms)
 	critical_exit();
 }
 
+int
+rms_try_rlock(struct rmslock *rms)
+{
+	int *influx;
+
+	critical_enter();
+	influx = zpcpu_get(rms->readers_influx);
+	__compiler_membar();
+	*influx = 1;
+	__compiler_membar();
+	if (__predict_false(rms->writers > 0)) {
+		__compiler_membar();
+		*influx = 0;
+		critical_exit();
+		return (0);
+	}
+	__compiler_membar();
+	(*zpcpu_get(rms->readers_pcpu))++;
+	__compiler_membar();
+	*influx = 0;
+	critical_exit();
+	return (1);
+}
+
 static void __noinline
 rms_runlock_fallback(struct rmslock *rms)
 {
diff --git a/sys/sys/rmlock.h b/sys/sys/rmlock.h
index 0fd4406d0886..ba2b9bbb732d 100644
--- a/sys/sys/rmlock.h
+++ b/sys/sys/rmlock.h
@@ -136,9 +136,21 @@ struct rm_args {
 void	rms_init(struct rmslock *rms, const char *name);
 void	rms_destroy(struct rmslock *rms);
 void	rms_rlock(struct rmslock *rms);
+int	rms_try_rlock(struct rmslock *rms);
 void	rms_runlock(struct rmslock *rms);
 void	rms_wlock(struct rmslock *rms);
 void	rms_wunlock(struct rmslock *rms);
 
+/*
+ * Writers are not explicitly tracked, thus until that changes the best we can
+ * do is indicate the lock is taken for writing by *someone*.
+ */
+static inline int
+rms_wowned(struct rmslock *rms)
+{
+
+	return (rms->writers > 0);
+}
+
 #endif /* _KERNEL */
 #endif /* !_SYS_RMLOCK_H_ */