Fix typo
[fio.git] / cgroup.c
CommitLineData
a696fa2a
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1/*
2 * Code related to setting up a blkio cgroup
3 */
4#include <stdio.h>
5#include <stdlib.h>
6adb38a1 6#include <mntent.h>
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7#include <sys/stat.h>
8#include <sys/types.h>
a696fa2a 9#include "fio.h"
39f22027 10#include "flist.h"
a696fa2a 11#include "cgroup.h"
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12#include "smalloc.h"
13
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14static struct fio_mutex *lock;
15
16struct cgroup_member {
17 struct flist_head list;
18 char *root;
7de87099 19 unsigned int cgroup_nodelete;
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20};
21
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22static char *find_cgroup_mnt(struct thread_data *td)
23{
24 char *mntpoint = NULL;
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25 struct mntent *mnt, dummy;
26 char buf[256] = {0};
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27 FILE *f;
28
29 f = setmntent("/proc/mounts", "r");
30 if (!f) {
31 td_verror(td, errno, "setmntent /proc/mounts");
32 return NULL;
33 }
34
599e72b7 35 while ((mnt = getmntent_r(f, &dummy, buf, sizeof(buf))) != NULL) {
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36 if (!strcmp(mnt->mnt_type, "cgroup") &&
37 strstr(mnt->mnt_opts, "blkio"))
38 break;
39 }
40
41 if (mnt)
42 mntpoint = smalloc_strdup(mnt->mnt_dir);
43 else
44 log_err("fio: cgroup blkio does not appear to be mounted\n");
45
46 endmntent(f);
47 return mntpoint;
48}
49
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VG
50static void add_cgroup(struct thread_data *td, const char *name,
51 struct flist_head *clist)
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52{
53 struct cgroup_member *cm;
54
55 cm = smalloc(sizeof(*cm));
56 INIT_FLIST_HEAD(&cm->list);
57 cm->root = smalloc_strdup(name);
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58 if (td->o.cgroup_nodelete)
59 cm->cgroup_nodelete = 1;
39f22027 60 fio_mutex_down(lock);
dae5341c 61 flist_add_tail(&cm->list, clist);
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62 fio_mutex_up(lock);
63}
64
dae5341c 65void cgroup_kill(struct flist_head *clist)
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66{
67 struct flist_head *n, *tmp;
68 struct cgroup_member *cm;
69
70 fio_mutex_down(lock);
39f22027 71
dae5341c 72 flist_for_each_safe(n, tmp, clist) {
39f22027 73 cm = flist_entry(n, struct cgroup_member, list);
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74 if (!cm->cgroup_nodelete)
75 rmdir(cm->root);
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76 flist_del(&cm->list);
77 sfree(cm->root);
78 sfree(cm);
79 }
80
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81 fio_mutex_up(lock);
82}
a696fa2a 83
6adb38a1 84static char *get_cgroup_root(struct thread_data *td, char *mnt)
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85{
86 char *str = malloc(64);
87
88 if (td->o.cgroup)
6adb38a1 89 sprintf(str, "%s/%s", mnt, td->o.cgroup);
a696fa2a 90 else
6adb38a1 91 sprintf(str, "%s/%s", mnt, td->o.name);
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92
93 return str;
94}
95
8a4d0ff0
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96static int write_int_to_file(struct thread_data *td, const char *path,
97 const char *filename, unsigned int val,
98 const char *onerr)
a696fa2a 99{
3858bf9e 100 char tmp[256];
a696fa2a 101 FILE *f;
3858bf9e 102
8a4d0ff0 103 sprintf(tmp, "%s/%s", path, filename);
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104 f = fopen(tmp, "w");
105 if (!f) {
8a4d0ff0 106 td_verror(td, errno, onerr);
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107 return 1;
108 }
109
8a4d0ff0 110 fprintf(f, "%u", val);
a696fa2a 111 fclose(f);
a696fa2a 112 return 0;
8a4d0ff0 113
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114}
115
8a4d0ff0 116static int cgroup_write_pid(struct thread_data *td, const char *root)
a696fa2a 117{
8a4d0ff0 118 unsigned int val = td->pid;
a696fa2a 119
8a4d0ff0 120 return write_int_to_file(td, root, "tasks", val, "cgroup write pid");
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121}
122
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123/*
124 * Move pid to root class
125 */
6adb38a1 126static int cgroup_del_pid(struct thread_data *td, char *mnt)
3858bf9e 127{
6adb38a1 128 return cgroup_write_pid(td, mnt);
3858bf9e 129}
a696fa2a 130
6adb38a1 131int cgroup_setup(struct thread_data *td, struct flist_head *clist, char **mnt)
a696fa2a 132{
8a4d0ff0 133 char *root;
a696fa2a 134
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135 if (!*mnt) {
136 *mnt = find_cgroup_mnt(td);
137 if (!*mnt)
138 return 1;
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139 }
140
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141 /*
142 * Create container, if it doesn't exist
143 */
6adb38a1 144 root = get_cgroup_root(td, *mnt);
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145 if (mkdir(root, 0755) < 0) {
146 int __e = errno;
147
148 if (__e != EEXIST) {
149 td_verror(td, __e, "cgroup mkdir");
6adb38a1 150 log_err("fio: path %s\n", root);
3858bf9e 151 goto err;
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152 }
153 } else
7de87099 154 add_cgroup(td, root, clist);
a696fa2a 155
39f22027 156 if (td->o.cgroup_weight) {
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157 if (write_int_to_file(td, root, "blkio.weight",
158 td->o.cgroup_weight,
159 "cgroup open weight"))
3858bf9e 160 goto err;
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161 }
162
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163 if (!cgroup_write_pid(td, root)) {
164 free(root);
165 return 0;
166 }
a696fa2a 167
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168err:
169 free(root);
170 return 1;
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171}
172
6adb38a1 173void cgroup_shutdown(struct thread_data *td, char **mnt)
a696fa2a 174{
6adb38a1 175 if (*mnt == NULL)
ddf16fe4 176 return;
ed81ee19 177 if (!td->o.cgroup_weight && !td->o.cgroup)
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178 return;
179
6adb38a1 180 cgroup_del_pid(td, *mnt);
39f22027 181}
a696fa2a 182
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183static void fio_init cgroup_init(void)
184{
185 lock = fio_mutex_init(1);
186}
187
188static void fio_exit cgroup_exit(void)
189{
190 fio_mutex_remove(lock);
a696fa2a 191}