xref: /illumos-gate/usr/src/cmd/dtrace/demo/sched/whoqueue.d (revision eb633035c80613ec93d62f90482837adaaf21a0a)
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 #pragma D option quiet
28 #pragma D option nspec=4
29 #pragma D option specsize=100k
30 
31 int maxlen;
32 int spec[int];
33 
34 sched:::enqueue
35 {
36 	this->len = ++qlen[this->cpu = args[2]->cpu_id];
37 	in[args[0]->pr_addr] = timestamp;
38 }
39 
40 sched:::enqueue
41 /this->len > maxlen && spec[this->cpu]/
42 {
43 	/*
44 	 * There is already a speculation for this CPU.  We just set a new
45 	 * record, so we'll discard the old one.
46 	 */
47 	discard(spec[this->cpu]);
48 }
49 
50 sched:::enqueue
51 /this->len > maxlen/
52 {
53 	/*
54 	 * We have a winner.  Set the new maximum length and set the timestamp
55 	 * of the longest length.
56 	 */
57 	maxlen = this->len;
58 	longtime[this->cpu] = timestamp;
59 
60 	/*
61 	 * Now start a new speculation, and speculatively trace the length.
62 	 */
63 	this->spec = spec[this->cpu] = speculation();
64 	speculate(this->spec);
65 	printf("Run queue of length %d:\n", this->len);
66 }
67 
68 sched:::dequeue
69 /(this->in = in[args[0]->pr_addr]) &&
70     this->in <= longtime[this->cpu = args[2]->cpu_id]/
71 {
72 	speculate(spec[this->cpu]);
73 	printf("  %d/%d (%s)\n",
74 	    args[1]->pr_pid, args[0]->pr_lwpid,
75 	    stringof(args[1]->pr_fname));
76 }
77 
78 sched:::dequeue
79 /qlen[args[2]->cpu_id]/
80 {
81 	in[args[0]->pr_addr] = 0;
82 	this->len = --qlen[args[2]->cpu_id];
83 }
84 
85 sched:::dequeue
86 /this->len == 0 && spec[this->cpu]/
87 {
88 	/*
89 	 * We just processed the last thread that was enqueued at the time
90 	 * of longest length; commit the speculation, which by now contains
91 	 * each thread that was enqueued when the queue was longest.
92 	 */
93 	commit(spec[this->cpu]);
94 	spec[this->cpu] = 0;
95 }
96