1 /**
2 * collectd - src/contextswitch.c
3 * Copyright (C) 2009 Patrik Weiskircher
4 * Copyright (C) 2010 Kimo Rosenbaum
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; only version 2 of the License is applicable.
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 * Patrik Weiskircher <weiskircher at inqnet.at>
21 * Kimo Rosenbaum <http://github.com/kimor79>
22 **/
24 #include "collectd.h"
26 #include "common.h"
27 #include "plugin.h"
29 #ifdef HAVE_SYS_SYSCTL_H
30 # include <sys/sysctl.h>
31 #endif
33 #if HAVE_SYSCTLBYNAME
34 /* no global variables */
35 /* #endif HAVE_SYSCTLBYNAME */
37 #elif KERNEL_LINUX
38 /* no global variables */
39 /* #endif KERNEL_LINUX */
41 #elif HAVE_PERFSTAT
42 # include <sys/protosw.h>
43 # include <libperfstat.h>
44 /* #endif HAVE_PERFSTAT */
46 #else
47 # error "No applicable input method."
48 #endif
50 static void cs_submit (derive_t context_switches)
51 {
52 value_list_t vl = VALUE_LIST_INIT;
54 vl.values = &(value_t) { .derive = context_switches };
55 vl.values_len = 1;
56 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
57 sstrncpy (vl.plugin, "contextswitch", sizeof (vl.plugin));
58 sstrncpy (vl.type, "contextswitch", sizeof (vl.type));
60 plugin_dispatch_values (&vl);
61 }
63 static int cs_read (void)
64 {
65 #if HAVE_SYSCTLBYNAME
66 int value = 0;
67 size_t value_len = sizeof (value);
68 int status;
70 status = sysctlbyname ("vm.stats.sys.v_swtch",
71 &value, &value_len,
72 /* new pointer = */ NULL, /* new length = */ 0);
73 if (status != 0)
74 {
75 ERROR("contextswitch plugin: sysctlbyname "
76 "(vm.stats.sys.v_swtch) failed");
77 return (-1);
78 }
80 cs_submit (value);
81 /* #endif HAVE_SYSCTLBYNAME */
83 #elif KERNEL_LINUX
84 FILE *fh;
85 char buffer[64];
86 int numfields;
87 char *fields[3];
88 derive_t result = 0;
89 int status = -2;
91 fh = fopen ("/proc/stat", "r");
92 if (fh == NULL) {
93 ERROR ("contextswitch plugin: unable to open /proc/stat: %s",
94 sstrerror (errno, buffer, sizeof (buffer)));
95 return (-1);
96 }
98 while (fgets(buffer, sizeof(buffer), fh) != NULL)
99 {
100 char *endptr;
102 numfields = strsplit(buffer, fields, STATIC_ARRAY_SIZE (fields));
103 if (numfields != 2)
104 continue;
106 if (strcmp("ctxt", fields[0]) != 0)
107 continue;
109 errno = 0;
110 endptr = NULL;
111 result = (derive_t) strtoll (fields[1], &endptr, /* base = */ 10);
112 if ((endptr == fields[1]) || (errno != 0)) {
113 ERROR ("contextswitch plugin: Cannot parse ctxt value: %s",
114 fields[1]);
115 status = -1;
116 break;
117 }
119 cs_submit(result);
120 status = 0;
121 break;
122 }
123 fclose(fh);
125 if (status == -2)
126 ERROR ("contextswitch plugin: Unable to find context switch value.");
127 /* #endif KERNEL_LINUX */
129 #elif HAVE_PERFSTAT
130 int status = 0;
131 perfstat_cpu_total_t perfcputotal;
133 status = perfstat_cpu_total(NULL, &perfcputotal, sizeof(perfstat_cpu_total_t), 1);
134 if (status < 0)
135 {
136 char errbuf[1024];
137 ERROR ("contextswitch plugin: perfstat_cpu_total: %s",
138 sstrerror (errno, errbuf, sizeof (errbuf)));
139 return (-1);
140 }
142 cs_submit(perfcputotal.pswitch);
143 status = 0;
144 #endif /* defined(HAVE_PERFSTAT) */
146 return status;
147 }
149 void module_register (void)
150 {
151 plugin_register_read ("contextswitch", cs_read);
152 } /* void module_register */