xref: /netbsd-src/sys/kern/subr_evcnt.c (revision c2f76ff004a2cb67efe5b12d97bd3ef7fe89e18d)
1 /* $NetBSD: subr_evcnt.c,v 1.8 2011/01/18 08:16:43 matt Exp $ */
2 
3 /*
4  * Copyright (c) 1996, 2000 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *          This product includes software developed for the
18  *          NetBSD Project.  See http://www.NetBSD.org/ for
19  *          information about NetBSD.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  *
34  * --(license Id: LICENSE.proto,v 1.1 2000/06/13 21:40:26 cgd Exp )--
35  */
36 
37 /*
38  * Copyright (c) 1992, 1993
39  *	The Regents of the University of California.  All rights reserved.
40  *
41  * This software was developed by the Computer Systems Engineering group
42  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
43  * contributed to Berkeley.
44  *
45  * All advertising materials mentioning features or use of this software
46  * must display the following acknowledgement:
47  *	This product includes software developed by the University of
48  *	California, Lawrence Berkeley Laboratories.
49  *
50  * Redistribution and use in source and binary forms, with or without
51  * modification, are permitted provided that the following conditions
52  * are met:
53  * 1. Redistributions of source code must retain the above copyright
54  *    notice, this list of conditions and the following disclaimer.
55  * 2. Redistributions in binary form must reproduce the above copyright
56  *    notice, this list of conditions and the following disclaimer in the
57  *    documentation and/or other materials provided with the distribution.
58  * 3. Neither the name of the University nor the names of its contributors
59  *    may be used to endorse or promote products derived from this software
60  *    without specific prior written permission.
61  *
62  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
63  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
64  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
65  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
66  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
67  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
68  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
69  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
70  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
71  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
72  * SUCH DAMAGE.
73  *
74  * from: Header: subr_autoconf.c,v 1.12 93/02/01 19:31:48 torek Exp  (LBL)
75  *
76  *	@(#)subr_autoconf.c	8.3 (Berkeley) 5/17/94
77  */
78 
79 #include <sys/cdefs.h>
80 __KERNEL_RCSID(0, "$NetBSD: subr_evcnt.c,v 1.8 2011/01/18 08:16:43 matt Exp $");
81 
82 #include <sys/param.h>
83 #include <sys/device.h>
84 #include <sys/mutex.h>
85 #include <sys/systm.h>
86 
87 /* list of all events */
88 struct evcntlist allevents = TAILQ_HEAD_INITIALIZER(allevents);
89 static kmutex_t evmtx;
90 static bool init_done;
91 
92 /*
93  * We need a dummy object to stuff into the evcnt link set to
94  * ensure that there always is at least one object in the set.
95  */
96 static struct evcnt dummy_static_evcnt;
97 __link_set_add_bss(evcnts, dummy_static_evcnt);
98 
99 /*
100  * Initialize event counters.  This does the attach procedure for
101  * each of the static event counters in the "evcnts" link set.
102  */
103 void
104 evcnt_init(void)
105 {
106 	__link_set_decl(evcnts, struct evcnt);
107 	struct evcnt * const *evp;
108 
109 	KASSERT(!init_done);
110 
111 	mutex_init(&evmtx, MUTEX_DEFAULT, IPL_NONE);
112 
113 	init_done = true;
114 
115 	__link_set_foreach(evp, evcnts) {
116 		if (*evp == &dummy_static_evcnt)
117 			continue;
118 		evcnt_attach_static(*evp);
119 	}
120 }
121 
122 /*
123  * Attach a statically-initialized event.  The type and string pointers
124  * are already set up.
125  */
126 void
127 evcnt_attach_static(struct evcnt *ev)
128 {
129 	int len;
130 
131 	KASSERTMSG(init_done,
132 	    ("%s: evcnt non initialized: group=<%s> name=<%s>",
133 	    __func__, ev->ev_group, ev->ev_name));
134 
135 	len = strlen(ev->ev_group);
136 #ifdef DIAGNOSTIC
137 	if (len >= EVCNT_STRING_MAX)		/* ..._MAX includes NUL */
138 		panic("evcnt_attach_static: group length (%s)", ev->ev_group);
139 #endif
140 	ev->ev_grouplen = len;
141 
142 	len = strlen(ev->ev_name);
143 #ifdef DIAGNOSTIC
144 	if (len >= EVCNT_STRING_MAX)		/* ..._MAX includes NUL */
145 		panic("evcnt_attach_static: name length (%s)", ev->ev_name);
146 #endif
147 	ev->ev_namelen = len;
148 
149 	mutex_enter(&evmtx);
150 	TAILQ_INSERT_TAIL(&allevents, ev, ev_list);
151 	mutex_exit(&evmtx);
152 }
153 
154 /*
155  * Attach a dynamically-initialized event.  Zero it, set up the type
156  * and string pointers and then act like it was statically initialized.
157  */
158 void
159 evcnt_attach_dynamic_nozero(struct evcnt *ev, int type,
160     const struct evcnt *parent, const char *group, const char *name)
161 {
162 
163 	ev->ev_type = type;
164 	ev->ev_parent = parent;
165 	ev->ev_group = group;
166 	ev->ev_name = name;
167 	evcnt_attach_static(ev);
168 }
169 /*
170  * Attach a dynamically-initialized event.  Zero it, set up the type
171  * and string pointers and then act like it was statically initialized.
172  */
173 void
174 evcnt_attach_dynamic(struct evcnt *ev, int type, const struct evcnt *parent,
175     const char *group, const char *name)
176 {
177 
178 	memset(ev, 0, sizeof *ev);
179 	evcnt_attach_dynamic_nozero(ev, type, parent, group, name);
180 }
181 
182 /*
183  * Detach an event.
184  */
185 void
186 evcnt_detach(struct evcnt *ev)
187 {
188 
189 	mutex_enter(&evmtx);
190 	TAILQ_REMOVE(&allevents, ev, ev_list);
191 	mutex_exit(&evmtx);
192 }
193