xref: /illumos-gate/usr/src/cmd/dtrace/demo/vars/rtime.d (revision 8b80e8cb6855118d46f605e91b5ed4ce83417395)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 syscall::read:entry
28 {
29 	self->t = timestamp;
30 }
31 
32 syscall::read:return
33 /self->t != 0/
34 {
35 	printf("%d/%d spent %d nsecs in read(2)\n",
36 	    pid, tid, timestamp - self->t);
37 
38 	/*
39 	 * We're done with this thread-local variable; assign zero to it to
40 	 * allow the DTrace runtime to reclaim the underlying storage.
41 	 */
42 	self->t = 0;
43 }
44