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