1 /**
2 * collectd - src/cpufreq.c
3 * Copyright (C) 2005-2007 Peter Holik
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors:
20 * Peter Holik <peter at holik.at>
21 **/
23 #include "collectd.h"
25 #include "common.h"
26 #include "plugin.h"
28 #define MODULE_NAME "cpufreq"
30 static int num_cpu = 0;
32 static int cpufreq_init(void) {
33 int status;
34 char filename[256];
36 num_cpu = 0;
38 while (1) {
39 status = ssnprintf(filename, sizeof(filename),
40 "/sys/devices/system/cpu/cpu%d/cpufreq/"
41 "scaling_cur_freq",
42 num_cpu);
43 if ((status < 1) || ((unsigned int)status >= sizeof(filename)))
44 break;
46 if (access(filename, R_OK))
47 break;
49 num_cpu++;
50 }
52 INFO("cpufreq plugin: Found %d CPU%s", num_cpu, (num_cpu == 1) ? "" : "s");
54 if (num_cpu == 0)
55 plugin_unregister_read("cpufreq");
57 return (0);
58 } /* int cpufreq_init */
60 static void cpufreq_submit(int cpu_num, double value) {
61 value_t values[1];
62 value_list_t vl = VALUE_LIST_INIT;
64 values[0].gauge = value;
66 vl.values = values;
67 vl.values_len = 1;
68 sstrncpy(vl.host, hostname_g, sizeof(vl.host));
69 sstrncpy(vl.plugin, "cpufreq", sizeof(vl.plugin));
70 sstrncpy(vl.type, "cpufreq", sizeof(vl.type));
71 ssnprintf(vl.type_instance, sizeof(vl.type_instance), "%i", cpu_num);
73 plugin_dispatch_values(&vl);
74 }
76 static int cpufreq_read(void) {
77 int status;
78 unsigned long long val;
79 FILE *fp;
80 char filename[256];
81 char buffer[16];
83 for (int i = 0; i < num_cpu; i++) {
84 status = ssnprintf(filename, sizeof(filename),
85 "/sys/devices/system/cpu/cpu%d/cpufreq/"
86 "scaling_cur_freq",
87 i);
88 if ((status < 1) || ((unsigned int)status >= sizeof(filename)))
89 return (-1);
91 if ((fp = fopen(filename, "r")) == NULL) {
92 char errbuf[1024];
93 WARNING("cpufreq: fopen (%s): %s", filename,
94 sstrerror(errno, errbuf, sizeof(errbuf)));
95 return (-1);
96 }
98 if (fgets(buffer, 16, fp) == NULL) {
99 char errbuf[1024];
100 WARNING("cpufreq: fgets: %s", sstrerror(errno, errbuf, sizeof(errbuf)));
101 fclose(fp);
102 return (-1);
103 }
105 if (fclose(fp)) {
106 char errbuf[1024];
107 WARNING("cpufreq: fclose: %s", sstrerror(errno, errbuf, sizeof(errbuf)));
108 }
110 /* You're seeing correctly: The file is reporting kHz values.. */
111 val = atoll(buffer) * 1000;
113 cpufreq_submit(i, val);
114 }
116 return (0);
117 } /* int cpufreq_read */
119 void module_register(void) {
120 plugin_register_init("cpufreq", cpufreq_init);
121 plugin_register_read("cpufreq", cpufreq_read);
122 }