--- init/main.c	2016-08-08 09:40:13.000000000 +0800
+++ init/main.c	2021-07-06 14:16:56.000000000 +0800
@@ -208,3 +208,9 @@
 	}
 	_exit(0);	/* NOTE! _exit, not exit() */
 }
+
+void print_nr(int sid)
+{
+	if (sid > 86)
+		printk(" --syscall: sid=%d, pid=%d\n", sid, current->pid);
+}