508ba90f144ed5f65b4017361ab19815434ed04d
1 /**
2 * collectd - src/cgroups.c
3 * Copyright (C) 2011 Michael Stapelberg
4 * Copyright (C) 2013 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; 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 * Michael Stapelberg <michael at stapelberg.de>
21 * Florian Forster <octo at collectd.org>
22 **/
24 #include "collectd.h"
26 #include "common.h"
27 #include "plugin.h"
28 #include "configfile.h"
29 #include "utils_mount.h"
30 #include "utils_ignorelist.h"
32 static char const *config_keys[] =
33 {
34 "CGroup",
35 "IgnoreSelected"
36 };
37 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
39 static ignorelist_t *il_cgroup = NULL;
41 __attribute__ ((nonnull(1)))
42 __attribute__ ((nonnull(2)))
43 static void cgroups_submit_one (char const *plugin_instance,
44 char const *type_instance, value_t value)
45 {
46 value_list_t vl = VALUE_LIST_INIT;
48 vl.values = &value;
49 vl.values_len = 1;
50 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
51 sstrncpy (vl.plugin, "cgroups", sizeof (vl.plugin));
52 sstrncpy (vl.plugin_instance, plugin_instance,
53 sizeof (vl.plugin_instance));
54 sstrncpy (vl.type, "cpu", sizeof (vl.type));
55 sstrncpy (vl.type_instance, type_instance,
56 sizeof (vl.type_instance));
58 plugin_dispatch_values (&vl);
59 } /* void cgroups_submit_one */
61 /*
62 * This callback reads the user/system CPU time for each cgroup.
63 */
64 static int read_cpuacct_procs (const char *dirname, char const *cgroup_name,
65 void *user_data)
66 {
67 char abs_path[PATH_MAX];
68 struct stat statbuf;
69 char buf[1024];
70 int status;
72 FILE *fh;
74 if (ignorelist_match (il_cgroup, cgroup_name))
75 return (0);
77 ssnprintf (abs_path, sizeof (abs_path), "%s/%s", dirname, cgroup_name);
79 status = lstat (abs_path, &statbuf);
80 if (status != 0)
81 {
82 ERROR ("cgroups plugin: stat (\"%s\") failed.",
83 abs_path);
84 return (-1);
85 }
87 /* We are only interested in directories, so skip everything else. */
88 if (!S_ISDIR (statbuf.st_mode))
89 return (0);
91 ssnprintf (abs_path, sizeof (abs_path), "%s/%s/cpuacct.stat",
92 dirname, cgroup_name);
93 fh = fopen (abs_path, "r");
94 if (fh == NULL)
95 {
96 char errbuf[1024];
97 ERROR ("cgroups plugin: fopen (\"%s\") failed: %s",
98 abs_path,
99 sstrerror (errno, errbuf, sizeof (errbuf)));
100 return (-1);
101 }
103 while (fgets (buf, sizeof (buf), fh) != NULL)
104 {
105 char *fields[8];
106 int numfields = 0;
107 char *key;
108 size_t key_len;
109 value_t value;
111 /* Expected format:
112 *
113 * user: 12345
114 * system: 23456
115 *
116 * Or:
117 *
118 * user 12345
119 * system 23456
120 */
121 strstripnewline (buf);
122 numfields = strsplit (buf, fields, STATIC_ARRAY_SIZE (fields));
123 if (numfields != 2)
124 continue;
126 key = fields[0];
127 key_len = strlen (key);
128 if (key_len < 2)
129 continue;
131 /* Strip colon off the first column, if found */
132 if (key[key_len - 1] == ':')
133 key[key_len - 1] = 0;
135 status = parse_value (fields[1], &value, DS_TYPE_DERIVE);
136 if (status != 0)
137 continue;
139 cgroups_submit_one (cgroup_name, key, value);
140 }
142 fclose (fh);
143 return (0);
144 } /* int read_cpuacct_procs */
146 /*
147 * Gets called for every file/folder in /sys/fs/cgroup/cpu,cpuacct (or
148 * wherever cpuacct is mounted on the system). Calls walk_directory with the
149 * read_cpuacct_procs callback on every folder it finds, such as "system".
150 */
151 static int read_cpuacct_root (const char *dirname, const char *filename,
152 void *user_data)
153 {
154 char abs_path[PATH_MAX];
155 struct stat statbuf;
156 int status;
158 ssnprintf (abs_path, sizeof (abs_path), "%s/%s", dirname, filename);
160 status = lstat (abs_path, &statbuf);
161 if (status != 0)
162 {
163 ERROR ("cgroups plugin: stat (%s) failed.", abs_path);
164 return (-1);
165 }
167 if (S_ISDIR (statbuf.st_mode))
168 {
169 status = walk_directory (abs_path, read_cpuacct_procs,
170 /* user_data = */ NULL,
171 /* include_hidden = */ 0);
172 return (status);
173 }
175 return (0);
176 }
178 static int cgroups_init (void)
179 {
180 if (il_cgroup == NULL)
181 il_cgroup = ignorelist_create (1);
183 return (0);
184 }
186 static int cgroups_config (const char *key, const char *value)
187 {
188 cgroups_init ();
190 if (strcasecmp (key, "CGroup") == 0)
191 {
192 if (ignorelist_add (il_cgroup, value))
193 return (1);
194 return (0);
195 }
196 else if (strcasecmp (key, "IgnoreSelected") == 0)
197 {
198 if (IS_TRUE (value))
199 ignorelist_set_invert (il_cgroup, 0);
200 else
201 ignorelist_set_invert (il_cgroup, 1);
202 return (0);
203 }
205 return (-1);
206 }
208 static int cgroups_read (void)
209 {
210 cu_mount_t *mnt_list;
211 cu_mount_t *mnt_ptr;
212 _Bool cgroup_found = 0;
214 mnt_list = NULL;
215 if (cu_mount_getlist (&mnt_list) == NULL)
216 {
217 ERROR ("cgroups plugin: cu_mount_getlist failed.");
218 return (-1);
219 }
221 for (mnt_ptr = mnt_list; mnt_ptr != NULL; mnt_ptr = mnt_ptr->next)
222 {
223 /* Find the cgroup mountpoint which contains the cpuacct
224 * controller. */
225 if ((strcmp(mnt_ptr->type, "cgroup") != 0)
226 || !cu_mount_checkoption(mnt_ptr->options,
227 "cpuacct", /* full = */ 1))
228 continue;
230 walk_directory (mnt_ptr->dir, read_cpuacct_root,
231 /* user_data = */ NULL,
232 /* include_hidden = */ 0);
233 cgroup_found = 1;
234 /* It doesn't make sense to check other cpuacct mount-points
235 * (if any), they contain the same data. */
236 break;
237 }
239 cu_mount_freelist (mnt_list);
241 if (!cgroup_found)
242 {
243 WARNING ("cgroups plugin: Unable to find cgroup "
244 "mount-point with the \"cpuacct\" option.");
245 return (-1);
246 }
248 return (0);
249 } /* int cgroup_read */
251 void module_register (void)
252 {
253 plugin_register_config ("cgroups", cgroups_config,
254 config_keys, config_keys_num);
255 plugin_register_init ("cgroups", cgroups_init);
256 plugin_register_read ("cgroups", cgroups_read);
257 } /* void module_register */