xref: /openbsd-src/sys/kern/subr_evcount.c (revision 6440a3034c3f92f556e920c8f03f14b0ebda804a)
1 /*	$OpenBSD: subr_evcount.c,v 1.4 2004/09/29 07:37:04 miod Exp $ */
2 /*
3  * Copyright (c) 2004 Artur Grabowski <art@openbsd.org>
4  * Copyright (c) 2004 Aaron Campbell <aaron@openbsd.org>
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  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
17  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
18  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
19  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20  * EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/param.h>
29 #include <sys/evcount.h>
30 #include <sys/timeout.h>
31 #include <sys/kernel.h>
32 #include <sys/systm.h>
33 #include <sys/sysctl.h>
34 
35 #ifdef __HAVE_EVCOUNT
36 
37 static TAILQ_HEAD(,evcount) evcount_list;
38 static struct evcount *evcount_next_sync;
39 
40 /*
41  * Standard evcount parents.
42  */
43 struct evcount evcount_intr;
44 
45 void evcount_timeout(void *);
46 void evcount_init(void);
47 
48 void
49 evcount_init(void)
50 {
51 	TAILQ_INIT(&evcount_list);
52 
53 	evcount_attach(&evcount_intr, "intr", NULL, NULL);
54 }
55 
56 
57 void
58 evcount_attach(ec, name, data, parent)
59 	struct evcount *ec;
60 	const char *name;
61 	void *data;
62 	struct evcount *parent;
63 {
64 	static int nextid = 0;
65 
66 	if (nextid == 0) {
67 		nextid++;		/* start with 1 */
68 		evcount_init();
69 	}
70 
71 	memset(ec, 0, sizeof(*ec));
72 	ec->ec_name = name;
73 	ec->ec_parent = parent;
74 	ec->ec_id = nextid++;
75 	ec->ec_data = data;
76 	TAILQ_INSERT_TAIL(&evcount_list, ec, next);
77 }
78 
79 void
80 evcount_detach(ec)
81 	struct evcount *ec;
82 {
83 	if (evcount_next_sync == ec)
84 		evcount_next_sync = TAILQ_NEXT(ec, next);
85 
86 	TAILQ_REMOVE(&evcount_list, ec, next);
87 }
88 
89 int
90 evcount_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
91 	int *name;
92 	u_int namelen;
93 	void *oldp;
94 	size_t *oldlenp;
95 	void *newp;
96 	size_t newlen;
97 {
98 	int error = 0, s, nintr, i;
99 	struct evcount *ec;
100 	u_int64_t count;
101 
102 	if (newp != NULL)
103 		return (EPERM);
104 
105 	if (name[0] != KERN_INTRCNT_NUM) {
106 		if (namelen != 2)
107 			return (ENOTDIR);
108 		if (name[1] < 0)
109 			return (EINVAL);
110 		i = name[1];
111 	} else
112 		i = -1;
113 
114 	nintr = 0;
115 	TAILQ_FOREACH(ec, &evcount_list, next) {
116 		if (ec->ec_parent != &evcount_intr)
117 			continue;
118 		if (nintr++ == i)
119 			break;
120 	}
121 
122 	switch (name[0]) {
123 	case KERN_INTRCNT_NUM:
124 		error = sysctl_rdint(oldp, oldlenp, NULL, nintr);
125 		break;
126 	case KERN_INTRCNT_CNT:
127 		if (ec == NULL)
128 			return (ENOENT);
129 		s = splhigh();
130 		count = ec->ec_count;
131 		splx(s);
132 		error = sysctl_rdquad(oldp, oldlenp, NULL, count);
133 		break;
134 	case KERN_INTRCNT_NAME:
135 		if (ec == NULL)
136 			return (ENOENT);
137 		error = sysctl_rdstring(oldp, oldlenp, NULL, ec->ec_name);
138 		break;
139 	case KERN_INTRCNT_VECTOR:
140 		if (ec == NULL || ec->ec_data == NULL)
141 			return (ENOENT);
142 		error = sysctl_rdint(oldp, oldlenp, NULL,
143 		    *((int *)ec->ec_data));
144 		break;
145 	default:
146 		error = EOPNOTSUPP;
147 		break;
148 	}
149 
150 	return (error);
151 }
152 
153 #endif /* __HAVE_EVCOUNT */
154