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"
25 #include "common.h"
26 #include "plugin.h"
27 #include "configfile.h"
28 #include "utils_mount.h"
29 #include "utils_ignorelist.h"
31 static char const *config_keys[] =
32 {
33 "CGroup",
34 "IgnoreSelected"
35 };
36 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
38 static ignorelist_t *il_cgroup = NULL;
40 __attribute__ ((nonnull(1)))
41 __attribute__ ((nonnull(2)))
42 static void cgroups_submit_one (char const *plugin_instance,
43 char const *type_instance, value_t value)
44 {
45 value_list_t vl = VALUE_LIST_INIT;
47 vl.values = &value;
48 vl.values_len = 1;
49 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
50 sstrncpy (vl.plugin, "cgroups", sizeof (vl.plugin));
51 sstrncpy (vl.plugin_instance, plugin_instance,
52 sizeof (vl.plugin_instance));
53 sstrncpy (vl.type, "cpu", sizeof (vl.type));
54 sstrncpy (vl.type_instance, type_instance,
55 sizeof (vl.type_instance));
57 plugin_dispatch_values (&vl);
58 } /* void cgroups_submit_one */
60 /*
61 * This callback reads the user/system CPU time for each cgroup.
62 */
63 static int read_cpuacct_procs (const char *dirname, char const *cgroup_name,
64 void *user_data)
65 {
66 char abs_path[PATH_MAX];
67 struct stat statbuf;
68 char buf[1024];
69 int status;
71 FILE *fh;
73 if (ignorelist_match (il_cgroup, cgroup_name))
74 return (0);
76 ssnprintf (abs_path, sizeof (abs_path), "%s/%s", dirname, cgroup_name);
78 status = lstat (abs_path, &statbuf);
79 if (status != 0)
80 {
81 ERROR ("cgroups plugin: stat (\"%s\") failed.",
82 abs_path);
83 return (-1);
84 }
86 /* We are only interested in directories, so skip everything else. */
87 if (!S_ISDIR (statbuf.st_mode))
88 return (0);
90 ssnprintf (abs_path, sizeof (abs_path), "%s/%s/cpuacct.stat",
91 dirname, cgroup_name);
92 fh = fopen (abs_path, "r");
93 if (fh == NULL)
94 {
95 char errbuf[1024];
96 ERROR ("cgroups pluign: fopen (\"%s\") failed: %s",
97 abs_path,
98 sstrerror (errno, errbuf, sizeof (errbuf)));
99 return (-1);
100 }
102 while (fgets (buf, sizeof (buf), fh) != NULL)
103 {
104 char *fields[8];
105 int numfields = 0;
106 char *key;
107 size_t key_len;
108 value_t value;
110 /* Expected format:
111 *
112 * user: 12345
113 * system: 23456
114 */
115 strstripnewline (buf);
116 numfields = strsplit (buf, fields, STATIC_ARRAY_SIZE (fields));
117 if (numfields != 2)
118 continue;
120 key = fields[0];
121 key_len = strlen (key);
122 if (key_len < 2)
123 continue;
125 /* Strip colon off the first column */
126 if (key[key_len - 1] != ':')
127 continue;
128 key[key_len - 1] = 0;
130 status = parse_value (fields[1], &value, DS_TYPE_DERIVE);
131 if (status != 0)
132 continue;
134 cgroups_submit_one (cgroup_name, key, value);
135 }
137 fclose (fh);
138 return (0);
139 } /* int read_cpuacct_procs */
141 /*
142 * Gets called for every file/folder in /sys/fs/cgroup/cpu,cpuacct (or
143 * whereever cpuacct is mounted on the system). Calls walk_directory with the
144 * read_cpuacct_procs callback on every folder it finds, such as "system".
145 */
146 static int read_cpuacct_root (const char *dirname, const char *filename,
147 void *user_data)
148 {
149 char abs_path[PATH_MAX];
150 struct stat statbuf;
151 int status;
153 ssnprintf (abs_path, sizeof (abs_path), "%s/%s", dirname, filename);
155 status = lstat (abs_path, &statbuf);
156 if (status != 0)
157 {
158 ERROR ("cgroups plugin: stat (%s) failed.", abs_path);
159 return (-1);
160 }
162 if (S_ISDIR (statbuf.st_mode))
163 {
164 status = walk_directory (abs_path, read_cpuacct_procs,
165 /* user_data = */ NULL,
166 /* include_hidden = */ 0);
167 return (status);
168 }
170 return (0);
171 }
173 static int cgroups_init (void)
174 {
175 if (il_cgroup == NULL)
176 il_cgroup = ignorelist_create (1);
178 return (0);
179 }
181 static int cgroups_config (const char *key, const char *value)
182 {
183 cgroups_init ();
185 if (strcasecmp (key, "CGroup") == 0)
186 {
187 if (ignorelist_add (il_cgroup, value))
188 return (1);
189 return (0);
190 }
191 else if (strcasecmp (key, "IgnoreSelected") == 0)
192 {
193 if (IS_TRUE (value))
194 ignorelist_set_invert (il_cgroup, 0);
195 else
196 ignorelist_set_invert (il_cgroup, 1);
197 return (0);
198 }
200 return (-1);
201 }
203 static int cgroups_read (void)
204 {
205 cu_mount_t *mnt_list;
206 cu_mount_t *mnt_ptr;
207 _Bool cgroup_found = 0;
209 mnt_list = NULL;
210 if (cu_mount_getlist (&mnt_list) == NULL)
211 {
212 ERROR ("cgroups plugin: cu_mount_getlist failed.");
213 return (-1);
214 }
216 for (mnt_ptr = mnt_list; mnt_ptr != NULL; mnt_ptr = mnt_ptr->next)
217 {
218 /* Find the cgroup mountpoint which contains the cpuacct
219 * controller. */
220 if (strcmp(mnt_ptr->type, "cgroup") != 0 ||
221 !cu_mount_getoptionvalue(mnt_ptr->options, "cpuacct"))
222 continue;
224 walk_directory (mnt_ptr->dir, read_cpuacct_root,
225 /* user_data = */ NULL,
226 /* include_hidden = */ 0);
227 cgroup_found = 1;
228 /* It doesn't make sense to check other cpuacct mount-points
229 * (if any), they contain the same data. */
230 break;
231 }
233 cu_mount_freelist (mnt_list);
235 if (!cgroup_found)
236 {
237 WARNING ("cgroups plugin: Unable to find cgroup "
238 "mount-point with the \"cpuacct\" option.");
239 return (-1);
240 }
242 return (0);
243 } /* int cgroup_read */
245 void module_register (void)
246 {
247 plugin_register_config ("cgroups", cgroups_config,
248 config_keys, config_keys_num);
249 plugin_register_init ("cgroups", cgroups_init);
250 plugin_register_read ("cgroups", cgroups_read);
251 } /* void module_register */