xref: /openbsd-src/sys/kern/subr_evcount.c (revision e5157e49389faebcb42b7237d55fbf096d9c2523)
1 /*	$OpenBSD: subr_evcount.c,v 1.11 2014/09/14 14:17:25 jsg 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 static TAILQ_HEAD(,evcount) evcount_list = TAILQ_HEAD_INITIALIZER(evcount_list);
36 
37 void
38 evcount_attach(struct evcount *ec, const char *name, void *data)
39 {
40 	static int nextid = 0;
41 
42 	memset(ec, 0, sizeof(*ec));
43 	ec->ec_name = name;
44 	ec->ec_id = ++nextid;
45 	ec->ec_data = data;
46 	TAILQ_INSERT_TAIL(&evcount_list, ec, next);
47 }
48 
49 void
50 evcount_detach(struct evcount *ec)
51 {
52 	TAILQ_REMOVE(&evcount_list, ec, next);
53 }
54 
55 #ifndef	SMALL_KERNEL
56 
57 int
58 evcount_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
59     void *newp, size_t newlen)
60 {
61 	int error = 0, s, nintr, i;
62 	struct evcount *ec;
63 	u_int64_t count;
64 
65 	if (newp != NULL)
66 		return (EPERM);
67 
68 	if (name[0] != KERN_INTRCNT_NUM) {
69 		if (namelen != 2)
70 			return (ENOTDIR);
71 		if (name[1] < 0)
72 			return (EINVAL);
73 		i = name[1];
74 	} else
75 		i = -1;
76 
77 	nintr = 0;
78 	TAILQ_FOREACH(ec, &evcount_list, next) {
79 		if (nintr++ == i)
80 			break;
81 	}
82 
83 	switch (name[0]) {
84 	case KERN_INTRCNT_NUM:
85 		error = sysctl_rdint(oldp, oldlenp, NULL, nintr);
86 		break;
87 	case KERN_INTRCNT_CNT:
88 		if (ec == NULL)
89 			return (ENOENT);
90 		s = splhigh();
91 		count = ec->ec_count;
92 		splx(s);
93 		error = sysctl_rdquad(oldp, oldlenp, NULL, count);
94 		break;
95 	case KERN_INTRCNT_NAME:
96 		if (ec == NULL)
97 			return (ENOENT);
98 		error = sysctl_rdstring(oldp, oldlenp, NULL, ec->ec_name);
99 		break;
100 	case KERN_INTRCNT_VECTOR:
101 		if (ec == NULL || ec->ec_data == NULL)
102 			return (ENOENT);
103 		error = sysctl_rdint(oldp, oldlenp, NULL,
104 		    *((int *)ec->ec_data));
105 		break;
106 	default:
107 		error = EOPNOTSUPP;
108 		break;
109 	}
110 
111 	return (error);
112 }
113 #endif	/* SMALL_KERNEL */
114