1 /**
2 * collectd - src/irq.c
3 * Copyright (C) 2007 Peter Holik
4 * Copyright (C) 2011 Florian Forster
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; either version 2 of the License, or (at your
9 * option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License along
17 * with this program; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Authors:
21 * Peter Holik <peter at holik.at>
22 **/
24 #include "collectd.h"
26 #include "common.h"
27 #include "plugin.h"
28 #include "utils_ignorelist.h"
30 #if !KERNEL_LINUX
31 #error "No applicable input method."
32 #endif
34 /*
35 * (Module-)Global variables
36 */
37 static const char *config_keys[] = {"Irq", "IgnoreSelected"};
38 static int config_keys_num = STATIC_ARRAY_SIZE(config_keys);
40 static ignorelist_t *ignorelist = NULL;
42 /*
43 * Private functions
44 */
45 static int irq_config(const char *key, const char *value) {
46 if (ignorelist == NULL)
47 ignorelist = ignorelist_create(/* invert = */ 1);
49 if (strcasecmp(key, "Irq") == 0) {
50 ignorelist_add(ignorelist, value);
51 } else if (strcasecmp(key, "IgnoreSelected") == 0) {
52 int invert = 1;
53 if (IS_TRUE(value))
54 invert = 0;
55 ignorelist_set_invert(ignorelist, invert);
56 } else {
57 return (-1);
58 }
60 return (0);
61 }
63 static void irq_submit(const char *irq_name, derive_t value) {
64 value_list_t vl = VALUE_LIST_INIT;
66 if (ignorelist_match(ignorelist, irq_name) != 0)
67 return;
69 vl.values = &(value_t){.derive = value};
70 vl.values_len = 1;
71 sstrncpy(vl.plugin, "irq", sizeof(vl.plugin));
72 sstrncpy(vl.type, "irq", sizeof(vl.type));
73 sstrncpy(vl.type_instance, irq_name, sizeof(vl.type_instance));
75 plugin_dispatch_values(&vl);
76 } /* void irq_submit */
78 static int irq_read(void) {
79 FILE *fh;
80 char buffer[1024];
81 int cpu_count;
82 char *fields[256];
84 /*
85 * Example content:
86 * CPU0 CPU1 CPU2 CPU3
87 * 0: 2574 1 3 2 IO-APIC-edge timer
88 * 1: 102553 158669 218062 70587 IO-APIC-edge i8042
89 * 8: 0 0 0 1 IO-APIC-edge rtc0
90 */
91 fh = fopen("/proc/interrupts", "r");
92 if (fh == NULL) {
93 char errbuf[1024];
94 ERROR("irq plugin: fopen (/proc/interrupts): %s",
95 sstrerror(errno, errbuf, sizeof(errbuf)));
96 return (-1);
97 }
99 /* Get CPU count from the first line */
100 if (fgets(buffer, sizeof(buffer), fh) != NULL) {
101 cpu_count = strsplit(buffer, fields, STATIC_ARRAY_SIZE(fields));
102 } else {
103 ERROR("irq plugin: unable to get CPU count from first line "
104 "of /proc/interrupts");
105 fclose(fh);
106 return (-1);
107 }
109 while (fgets(buffer, sizeof(buffer), fh) != NULL) {
110 char *irq_name;
111 size_t irq_name_len;
112 derive_t irq_value;
113 int i;
114 int fields_num;
115 int irq_values_to_parse;
117 fields_num = strsplit(buffer, fields, STATIC_ARRAY_SIZE(fields));
118 if (fields_num < 2)
119 continue;
121 /* Parse this many numeric fields, skip the rest
122 * (+1 because first there is a name of irq in each line) */
123 if (fields_num >= cpu_count + 1)
124 irq_values_to_parse = cpu_count;
125 else
126 irq_values_to_parse = fields_num - 1;
128 /* First field is irq name and colon */
129 irq_name = fields[0];
130 irq_name_len = strlen(irq_name);
131 if (irq_name_len < 2)
132 continue;
134 /* Check if irq name ends with colon.
135 * Otherwise it's a header. */
136 if (irq_name[irq_name_len - 1] != ':')
137 continue;
139 /* Is it the the ARM fast interrupt (FIQ)? */
140 if (irq_name_len == 4 && (strncmp(irq_name, "FIQ:", 4) == 0))
141 continue;
143 irq_name[irq_name_len - 1] = 0;
144 irq_name_len--;
146 irq_value = 0;
147 for (i = 1; i <= irq_values_to_parse; i++) {
148 /* Per-CPU value */
149 value_t v;
150 int status;
152 status = parse_value(fields[i], &v, DS_TYPE_DERIVE);
153 if (status != 0)
154 break;
156 irq_value += v.derive;
157 } /* for (i) */
159 /* No valid fields -> do not submit anything. */
160 if (i <= 1)
161 continue;
163 irq_submit(irq_name, irq_value);
164 }
166 fclose(fh);
168 return (0);
169 } /* int irq_read */
171 void module_register(void) {
172 plugin_register_config("irq", irq_config, config_keys, config_keys_num);
173 plugin_register_read("irq", irq_read);
174 } /* void module_register */