xref: /freebsd/share/dtrace/blocking (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
1#!/usr/sbin/dtrace -s
2/*-
3 * Copyright (c) 2015 Pawel Jakub Dawidek <pawel@dawidek.net>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 * This little script is for use with programs that use event loop and should
28 * sleep only when waiting for events (eg. via kevent(2)). When a program is
29 * going to sleep in the kernel, the script will show its name, PID, kernel
30 * stack trace and userland stack trace. Sleeping in kevent(2) is ignored.
31 *
32 * usage: blocking <execname>
33 */
34
35#pragma D option quiet
36
37syscall::kevent:entry
38/execname == $$1/
39{
40	self->inkevent = 1;
41}
42
43fbt::sleepq_add:entry
44/!self->inkevent && execname == $$1/
45{
46	printf("\n%s(%d) is blocking...\n", execname, pid);
47	stack();
48	ustack();
49}
50
51syscall::kevent:return
52/execname == $$1/
53{
54	self->inkevent = 0;
55}
56