v4.19.13 snapshot.
diff --git a/tools/include/linux/rcu.h b/tools/include/linux/rcu.h
new file mode 100644
index 0000000..7d02527
--- /dev/null
+++ b/tools/include/linux/rcu.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LIBLOCKDEP_RCU_H_
+#define _LIBLOCKDEP_RCU_H_
+
+int rcu_scheduler_active;
+
+static inline int rcu_lockdep_current_cpu_online(void)
+{
+ return 1;
+}
+
+static inline int rcu_is_cpu_idle(void)
+{
+ return 1;
+}
+
+static inline bool rcu_is_watching(void)
+{
+ return false;
+}
+
+#define rcu_assign_pointer(p, v) ((p) = (v))
+#define RCU_INIT_POINTER(p, v) p=(v)
+
+#endif