1 /* $OpenBSD: timer.c,v 1.1.1.1 2022/09/01 14:20:33 martijn Exp $ */
2
3 /*
4 * Copyright (c) 2008 Reyk Floeter <reyk@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <sys/queue.h>
20 #include <sys/types.h>
21 #include <sys/time.h>
22 #include <sys/sched.h>
23 #include <sys/socket.h>
24 #include <sys/sysctl.h>
25
26 #include <net/if.h>
27 #include <net/if_types.h>
28 #include <netinet/in.h>
29 #include <netinet/ip.h>
30 #include <netinet/ip_var.h>
31 #include <arpa/inet.h>
32
33 #include <stdlib.h>
34 #include <stdio.h>
35 #include <errno.h>
36 #include <event.h>
37 #include <fcntl.h>
38 #include <string.h>
39 #include <unistd.h>
40 #include <pwd.h>
41
42 #include "snmpd.h"
43 #include "mib.h"
44
45 void timer_cpu(int, short, void *);
46 int percentages(int, int64_t *, int64_t *, int64_t *, int64_t *);
47
48 static int64_t **cp_time;
49 static int64_t **cp_old;
50 static int64_t **cp_diff;
51 struct event cpu_ev;
52
53 void
timer_cpu(int fd,short event,void * arg)54 timer_cpu(int fd, short event, void *arg)
55 {
56 struct event *ev = (struct event *)arg;
57 struct timeval tv = { 60, 0 }; /* every 60 seconds */
58 int mib[3] = { CTL_KERN, KERN_CPTIME2, 0 }, n;
59 size_t len;
60 int64_t *cptime2;
61
62 len = CPUSTATES * sizeof(int64_t);
63 for (n = 0; n < snmpd_env->sc_ncpu; n++) {
64 mib[2] = n;
65 cptime2 = snmpd_env->sc_cpustates + (CPUSTATES * n);
66 if (sysctl(mib, 3, cp_time[n], &len, NULL, 0) == -1)
67 continue;
68 (void)percentages(CPUSTATES, cptime2, cp_time[n],
69 cp_old[n], cp_diff[n]);
70 #ifdef DEBUG
71 log_debug("timer_cpu: cpu%d %lld%% idle in %llds", n,
72 (cptime2[CP_IDLE] > 1000 ?
73 1000 : (cptime2[CP_IDLE] / 10)), (long long) tv.tv_sec);
74 #endif
75 }
76
77 evtimer_add(ev, &tv);
78 }
79
80 void
timer_init(void)81 timer_init(void)
82 {
83 int mib[] = { CTL_HW, HW_NCPU }, i;
84 size_t len;
85
86 len = sizeof(snmpd_env->sc_ncpu);
87 if (sysctl(mib, 2, &snmpd_env->sc_ncpu, &len, NULL, 0) == -1)
88 fatal("sysctl");
89
90 snmpd_env->sc_cpustates = calloc(snmpd_env->sc_ncpu,
91 CPUSTATES * sizeof(int64_t));
92 cp_time = calloc(snmpd_env->sc_ncpu, sizeof(int64_t *));
93 cp_old = calloc(snmpd_env->sc_ncpu, sizeof(int64_t *));
94 cp_diff = calloc(snmpd_env->sc_ncpu, sizeof(int64_t *));
95 if (snmpd_env->sc_cpustates == NULL ||
96 cp_time == NULL || cp_old == NULL || cp_diff == NULL)
97 fatal("calloc");
98 for (i = 0; i < snmpd_env->sc_ncpu; i++) {
99 cp_time[i] = calloc(CPUSTATES, sizeof(int64_t));
100 cp_old[i] = calloc(CPUSTATES, sizeof(int64_t));
101 cp_diff[i] = calloc(CPUSTATES, sizeof(int64_t));
102 if (cp_time[i] == NULL || cp_old[i] == NULL ||
103 cp_diff[i] == NULL)
104 fatal("calloc");
105 }
106
107 evtimer_set(&cpu_ev, timer_cpu, &cpu_ev);
108 timer_cpu(0, EV_TIMEOUT, &cpu_ev);
109 }
110
111 /*
112 * percentages() function to calculate CPU utilization.
113 * Source code derived from the top(1) utility:
114 *
115 * Copyright (c) 1984, 1989, William LeFebvre, Rice University
116 * Copyright (c) 1989, 1990, 1992, William LeFebvre, Northwestern University
117 *
118 * Redistribution and use in source and binary forms, with or without
119 * modification, are permitted provided that the following conditions
120 * are met:
121 * 1. Redistributions of source code must retain the above copyright
122 * notice, this list of conditions and the following disclaimer.
123 * 2. Redistributions in binary form must reproduce the above copyright
124 * notice, this list of conditions and the following disclaimer in the
125 * documentation and/or other materials provided with the distribution.
126 *
127 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
128 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
129 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
130 * IN NO EVENT SHALL THE AUTHOR OR HIS EMPLOYER BE LIABLE FOR ANY DIRECT, INDIRECT,
131 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
132 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
133 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
134 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
135 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
136 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
137 */
138 int
percentages(int cnt,int64_t * out,int64_t * new,int64_t * old,int64_t * diffs)139 percentages(int cnt, int64_t *out, int64_t *new, int64_t *old, int64_t *diffs)
140 {
141 int64_t change, total_change, *dp, half_total;
142 int i;
143
144 /* initialization */
145 total_change = 0;
146 dp = diffs;
147
148 /* calculate changes for each state and the overall change */
149 for (i = 0; i < cnt; i++) {
150 if ((change = *new - *old) < 0) {
151 /* this only happens when the counter wraps */
152 change = (*new - *old);
153 }
154 total_change += (*dp++ = change);
155 *old++ = *new++;
156 }
157
158 /* avoid divide by zero potential */
159 if (total_change == 0)
160 total_change = 1;
161
162 /* calculate percentages based on overall change, rounding up */
163 half_total = total_change / 2l;
164 for (i = 0; i < cnt; i++)
165 *out++ = ((*diffs++ * 1000 + half_total) / total_change);
166
167 /* return the total in case the caller wants to use it */
168 return (total_change);
169 }
170