Add a TCP state tracking script based on FreeBSD TCP SDTs

svn path=/head/; revision=279727

share/dtrace/Makefile

@@ -15,7 +15,8 @@ _toolkit=	toolkit
 SCRIPTS=	disklatency \
 		disklatencycmd \
 		hotopen \
-		nfsclienttime
+		nfsclienttime \
+		tcpstate
 
 SCRIPTSDIR= ${SHAREDIR}/dtrace
 

share/dtrace/tcpstate

@@ -0,0 +1,46 @@
+#!/usr/sbin/dtrace -s
+/*
+ * Copyright (c) 2015 George V. Neville-Neil
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ *
+ * The tcpstate D script shows TCP sockets transitioning between states.
+ *
+ * Usage: tcpstate
+ */
+
+#pragma D option quiet
+BEGIN
+{
+	printf("Old State\t\tNew State\n");
+}
+
+tcp:kernel::state-change
+{
+	newstate = args[3]->tcps_state;
+	oldstate = args[5]->tcps_state;
+	printf("%s\t\t%s\n", tcp_state_string[oldstate],
+			     tcp_state_string[newstate]);
+}