diff --git a/sys/kern/kern_mutex.c b/sys/kern/kern_mutex.c
--- a/sys/kern/kern_mutex.c
+++ b/sys/kern/kern_mutex.c
@@ -100,6 +100,8 @@
 #endif
 static void	lock_mtx(struct lock_object *lock, uintptr_t how);
 static void	lock_spin(struct lock_object *lock, uintptr_t how);
+static int	trylock_mtx(struct lock_object *lock, uintptr_t how);
+static int	trylock_spin(struct lock_object *lock, uintptr_t how);
 #ifdef KDTRACE_HOOKS
 static int	owner_mtx(const struct lock_object *lock,
 		    struct thread **owner);
@@ -118,6 +120,7 @@
 	.lc_ddb_show = db_show_mtx,
 #endif
 	.lc_lock = lock_mtx,
+	.lc_trylock = trylock_mtx,
 	.lc_unlock = unlock_mtx,
 #ifdef KDTRACE_HOOKS
 	.lc_owner = owner_mtx,
@@ -131,6 +134,7 @@
 	.lc_ddb_show = db_show_mtx,
 #endif
 	.lc_lock = lock_spin,
+	.lc_trylock = trylock_spin,
 	.lc_unlock = unlock_spin,
 #ifdef KDTRACE_HOOKS
 	.lc_owner = owner_mtx,
@@ -216,6 +220,20 @@
 	mtx_lock_spin((struct mtx *)lock);
 }
 
+static int
+trylock_mtx(struct lock_object *lock, uintptr_t how)
+{
+
+	return (mtx_trylock((struct mtx *)lock));
+}
+
+static int
+trylock_spin(struct lock_object *lock, uintptr_t how)
+{
+
+	return (mtx_trylock_spin((struct mtx *)lock));
+}
+
 static uintptr_t
 unlock_mtx(struct lock_object *lock)
 {
diff --git a/sys/kern/kern_rwlock.c b/sys/kern/kern_rwlock.c
--- a/sys/kern/kern_rwlock.c
+++ b/sys/kern/kern_rwlock.c
@@ -72,6 +72,7 @@
 #endif
 static void	assert_rw(const struct lock_object *lock, int what);
 static void	lock_rw(struct lock_object *lock, uintptr_t how);
+static int	trylock_rw(struct lock_object *lock, uintptr_t how);
 #ifdef KDTRACE_HOOKS
 static int	owner_rw(const struct lock_object *lock, struct thread **owner);
 #endif
@@ -85,6 +86,7 @@
 	.lc_ddb_show = db_show_rwlock,
 #endif
 	.lc_lock = lock_rw,
+	.lc_trylock = trylock_rw,
 	.lc_unlock = unlock_rw,
 #ifdef KDTRACE_HOOKS
 	.lc_owner = owner_rw,
@@ -176,6 +178,18 @@
 		rw_wlock(rw);
 }
 
+static int
+trylock_rw(struct lock_object *lock, uintptr_t how)
+{
+	struct rwlock *rw;
+
+	rw = (struct rwlock *)lock;
+	if (how)
+		return (rw_try_rlock(rw));
+	else
+		return (rw_try_wlock(rw));
+}
+
 static uintptr_t
 unlock_rw(struct lock_object *lock)
 {
diff --git a/sys/sys/lock.h b/sys/sys/lock.h
--- a/sys/sys/lock.h
+++ b/sys/sys/lock.h
@@ -66,6 +66,7 @@
 	int		(*lc_owner)(const struct lock_object *lock,
 			    struct thread **owner);
 	uintptr_t	(*lc_unlock)(struct lock_object *lock);
+	int		(*lc_trylock)(struct lock_object *lock, uintptr_t how);
 };
 
 #define	LC_SLEEPLOCK	0x00000001	/* Sleep lock. */