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