Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 1 | #ifndef _LINUX_CGROUP_H |
| 2 | #define _LINUX_CGROUP_H |
| 3 | /* |
| 4 | * cgroup interface |
| 5 | * |
| 6 | * Copyright (C) 2003 BULL SA |
| 7 | * Copyright (C) 2004-2006 Silicon Graphics, Inc. |
| 8 | * |
| 9 | */ |
| 10 | |
| 11 | #include <linux/sched.h> |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 12 | #include <linux/cpumask.h> |
| 13 | #include <linux/nodemask.h> |
| 14 | #include <linux/rcupdate.h> |
Balbir Singh | 846c7bb | 2007-10-18 23:39:44 -0700 | [diff] [blame] | 15 | #include <linux/cgroupstats.h> |
Cliff Wickman | 31a7df0 | 2008-02-07 00:14:42 -0800 | [diff] [blame] | 16 | #include <linux/prio_heap.h> |
Paul Menage | cc31edc | 2008-10-18 20:28:04 -0700 | [diff] [blame] | 17 | #include <linux/rwsem.h> |
KAMEZAWA Hiroyuki | 38460b4 | 2009-04-02 16:57:25 -0700 | [diff] [blame] | 18 | #include <linux/idr.h> |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 19 | |
| 20 | #ifdef CONFIG_CGROUPS |
| 21 | |
| 22 | struct cgroupfs_root; |
| 23 | struct cgroup_subsys; |
| 24 | struct inode; |
Paul Menage | 84eea84 | 2008-07-25 01:47:00 -0700 | [diff] [blame] | 25 | struct cgroup; |
KAMEZAWA Hiroyuki | 38460b4 | 2009-04-02 16:57:25 -0700 | [diff] [blame] | 26 | struct css_id; |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 27 | |
| 28 | extern int cgroup_init_early(void); |
| 29 | extern int cgroup_init(void); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 30 | extern void cgroup_lock(void); |
Paul E. McKenney | d11c563 | 2010-02-22 17:04:50 -0800 | [diff] [blame] | 31 | extern int cgroup_lock_is_held(void); |
Paul Menage | 84eea84 | 2008-07-25 01:47:00 -0700 | [diff] [blame] | 32 | extern bool cgroup_lock_live_group(struct cgroup *cgrp); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 33 | extern void cgroup_unlock(void); |
Paul Menage | b4f48b6 | 2007-10-18 23:39:33 -0700 | [diff] [blame] | 34 | extern void cgroup_fork(struct task_struct *p); |
| 35 | extern void cgroup_fork_callbacks(struct task_struct *p); |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 36 | extern void cgroup_post_fork(struct task_struct *p); |
Paul Menage | b4f48b6 | 2007-10-18 23:39:33 -0700 | [diff] [blame] | 37 | extern void cgroup_exit(struct task_struct *p, int run_callbacks); |
Balbir Singh | 846c7bb | 2007-10-18 23:39:44 -0700 | [diff] [blame] | 38 | extern int cgroupstats_build(struct cgroupstats *stats, |
| 39 | struct dentry *dentry); |
Ben Blum | e6a1105 | 2010-03-10 15:22:09 -0800 | [diff] [blame] | 40 | extern int cgroup_load_subsys(struct cgroup_subsys *ss); |
Ben Blum | cf5d594 | 2010-03-10 15:22:09 -0800 | [diff] [blame] | 41 | extern void cgroup_unload_subsys(struct cgroup_subsys *ss); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 42 | |
Alexey Dobriyan | 828c095 | 2009-10-01 15:43:56 -0700 | [diff] [blame] | 43 | extern const struct file_operations proc_cgroup_operations; |
Paul Menage | a424316 | 2007-10-18 23:39:35 -0700 | [diff] [blame] | 44 | |
Ben Blum | aae8aab | 2010-03-10 15:22:07 -0800 | [diff] [blame] | 45 | /* Define the enumeration of all builtin cgroup subsystems */ |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 46 | #define SUBSYS(_x) _x ## _subsys_id, |
| 47 | enum cgroup_subsys_id { |
| 48 | #include <linux/cgroup_subsys.h> |
Ben Blum | aae8aab | 2010-03-10 15:22:07 -0800 | [diff] [blame] | 49 | CGROUP_BUILTIN_SUBSYS_COUNT |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 50 | }; |
| 51 | #undef SUBSYS |
Ben Blum | aae8aab | 2010-03-10 15:22:07 -0800 | [diff] [blame] | 52 | /* |
| 53 | * This define indicates the maximum number of subsystems that can be loaded |
| 54 | * at once. We limit to this many since cgroupfs_root has subsys_bits to keep |
| 55 | * track of all of them. |
| 56 | */ |
| 57 | #define CGROUP_SUBSYS_COUNT (BITS_PER_BYTE*sizeof(unsigned long)) |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 58 | |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 59 | /* Per-subsystem/per-cgroup state maintained by the system. */ |
| 60 | struct cgroup_subsys_state { |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 61 | /* |
| 62 | * The cgroup that this subsystem is attached to. Useful |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 63 | * for subsystems that want to know about the cgroup |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 64 | * hierarchy structure |
| 65 | */ |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 66 | struct cgroup *cgroup; |
| 67 | |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 68 | /* |
| 69 | * State maintained by the cgroup system to allow subsystems |
Paul Menage | e7c5ec9 | 2009-01-07 18:08:38 -0800 | [diff] [blame] | 70 | * to be "busy". Should be accessed via css_get(), |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 71 | * css_tryget() and and css_put(). |
| 72 | */ |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 73 | |
| 74 | atomic_t refcnt; |
| 75 | |
| 76 | unsigned long flags; |
KAMEZAWA Hiroyuki | 38460b4 | 2009-04-02 16:57:25 -0700 | [diff] [blame] | 77 | /* ID for this css, if possible */ |
Arnd Bergmann | 2c392b8 | 2010-02-24 19:41:39 +0100 | [diff] [blame] | 78 | struct css_id __rcu *id; |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 79 | }; |
| 80 | |
| 81 | /* bits in struct cgroup_subsys_state flags field */ |
| 82 | enum { |
| 83 | CSS_ROOT, /* This CSS is the root of the subsystem */ |
Paul Menage | e7c5ec9 | 2009-01-07 18:08:38 -0800 | [diff] [blame] | 84 | CSS_REMOVED, /* This CSS is dead */ |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 85 | }; |
| 86 | |
Daisuke Nishimura | d7b9fff | 2010-03-10 15:22:05 -0800 | [diff] [blame] | 87 | /* Caller must verify that the css is not for root cgroup */ |
| 88 | static inline void __css_get(struct cgroup_subsys_state *css, int count) |
| 89 | { |
| 90 | atomic_add(count, &css->refcnt); |
| 91 | } |
| 92 | |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 93 | /* |
Paul Menage | e7c5ec9 | 2009-01-07 18:08:38 -0800 | [diff] [blame] | 94 | * Call css_get() to hold a reference on the css; it can be used |
| 95 | * for a reference obtained via: |
| 96 | * - an existing ref-counted reference to the css |
| 97 | * - task->cgroups for a locked task |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 98 | */ |
| 99 | |
| 100 | static inline void css_get(struct cgroup_subsys_state *css) |
| 101 | { |
| 102 | /* We don't need to reference count the root state */ |
| 103 | if (!test_bit(CSS_ROOT, &css->flags)) |
Daisuke Nishimura | d7b9fff | 2010-03-10 15:22:05 -0800 | [diff] [blame] | 104 | __css_get(css, 1); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 105 | } |
Paul Menage | e7c5ec9 | 2009-01-07 18:08:38 -0800 | [diff] [blame] | 106 | |
| 107 | static inline bool css_is_removed(struct cgroup_subsys_state *css) |
| 108 | { |
| 109 | return test_bit(CSS_REMOVED, &css->flags); |
| 110 | } |
| 111 | |
| 112 | /* |
| 113 | * Call css_tryget() to take a reference on a css if your existing |
| 114 | * (known-valid) reference isn't already ref-counted. Returns false if |
| 115 | * the css has been destroyed. |
| 116 | */ |
| 117 | |
| 118 | static inline bool css_tryget(struct cgroup_subsys_state *css) |
| 119 | { |
| 120 | if (test_bit(CSS_ROOT, &css->flags)) |
| 121 | return true; |
| 122 | while (!atomic_inc_not_zero(&css->refcnt)) { |
| 123 | if (test_bit(CSS_REMOVED, &css->flags)) |
| 124 | return false; |
Paul Menage | 804b3c2 | 2009-01-29 14:25:21 -0800 | [diff] [blame] | 125 | cpu_relax(); |
Paul Menage | e7c5ec9 | 2009-01-07 18:08:38 -0800 | [diff] [blame] | 126 | } |
| 127 | return true; |
| 128 | } |
| 129 | |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 130 | /* |
| 131 | * css_put() should be called to release a reference taken by |
Paul Menage | e7c5ec9 | 2009-01-07 18:08:38 -0800 | [diff] [blame] | 132 | * css_get() or css_tryget() |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 133 | */ |
| 134 | |
Daisuke Nishimura | d7b9fff | 2010-03-10 15:22:05 -0800 | [diff] [blame] | 135 | extern void __css_put(struct cgroup_subsys_state *css, int count); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 136 | static inline void css_put(struct cgroup_subsys_state *css) |
| 137 | { |
| 138 | if (!test_bit(CSS_ROOT, &css->flags)) |
Daisuke Nishimura | d7b9fff | 2010-03-10 15:22:05 -0800 | [diff] [blame] | 139 | __css_put(css, 1); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 140 | } |
| 141 | |
Paul Menage | 3116f0e | 2008-04-29 01:00:04 -0700 | [diff] [blame] | 142 | /* bits in struct cgroup flags field */ |
| 143 | enum { |
| 144 | /* Control Group is dead */ |
| 145 | CGRP_REMOVED, |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 146 | /* |
| 147 | * Control Group has previously had a child cgroup or a task, |
| 148 | * but no longer (only if CGRP_NOTIFY_ON_RELEASE is set) |
| 149 | */ |
Paul Menage | 3116f0e | 2008-04-29 01:00:04 -0700 | [diff] [blame] | 150 | CGRP_RELEASABLE, |
| 151 | /* Control Group requires release notifications to userspace */ |
| 152 | CGRP_NOTIFY_ON_RELEASE, |
KAMEZAWA Hiroyuki | ec64f51 | 2009-04-02 16:57:26 -0700 | [diff] [blame] | 153 | /* |
| 154 | * A thread in rmdir() is wating for this cgroup. |
| 155 | */ |
| 156 | CGRP_WAIT_ON_RMDIR, |
Paul Menage | 3116f0e | 2008-04-29 01:00:04 -0700 | [diff] [blame] | 157 | }; |
| 158 | |
Ben Blum | 72a8cb3 | 2009-09-23 15:56:27 -0700 | [diff] [blame] | 159 | /* which pidlist file are we talking about? */ |
| 160 | enum cgroup_filetype { |
| 161 | CGROUP_FILE_PROCS, |
| 162 | CGROUP_FILE_TASKS, |
| 163 | }; |
| 164 | |
| 165 | /* |
| 166 | * A pidlist is a list of pids that virtually represents the contents of one |
| 167 | * of the cgroup files ("procs" or "tasks"). We keep a list of such pidlists, |
| 168 | * a pair (one each for procs, tasks) for each pid namespace that's relevant |
| 169 | * to the cgroup. |
| 170 | */ |
Ben Blum | 102a775 | 2009-09-23 15:56:26 -0700 | [diff] [blame] | 171 | struct cgroup_pidlist { |
Ben Blum | 72a8cb3 | 2009-09-23 15:56:27 -0700 | [diff] [blame] | 172 | /* |
| 173 | * used to find which pidlist is wanted. doesn't change as long as |
| 174 | * this particular list stays in the list. |
| 175 | */ |
| 176 | struct { enum cgroup_filetype type; struct pid_namespace *ns; } key; |
Ben Blum | 102a775 | 2009-09-23 15:56:26 -0700 | [diff] [blame] | 177 | /* array of xids */ |
| 178 | pid_t *list; |
| 179 | /* how many elements the above list has */ |
| 180 | int length; |
| 181 | /* how many files are using the current array */ |
| 182 | int use_count; |
Ben Blum | 72a8cb3 | 2009-09-23 15:56:27 -0700 | [diff] [blame] | 183 | /* each of these stored in a list by its cgroup */ |
| 184 | struct list_head links; |
| 185 | /* pointer to the cgroup we belong to, for list removal purposes */ |
| 186 | struct cgroup *owner; |
| 187 | /* protects the other fields */ |
| 188 | struct rw_semaphore mutex; |
Ben Blum | 102a775 | 2009-09-23 15:56:26 -0700 | [diff] [blame] | 189 | }; |
| 190 | |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 191 | struct cgroup { |
| 192 | unsigned long flags; /* "unsigned long" so bitops work */ |
| 193 | |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 194 | /* |
| 195 | * count users of this cgroup. >0 means busy, but doesn't |
| 196 | * necessarily indicate the number of tasks in the cgroup |
| 197 | */ |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 198 | atomic_t count; |
| 199 | |
| 200 | /* |
| 201 | * We link our 'sibling' struct into our parent's 'children'. |
| 202 | * Our children link their 'sibling' into our 'children'. |
| 203 | */ |
| 204 | struct list_head sibling; /* my parent's children */ |
| 205 | struct list_head children; /* my children */ |
| 206 | |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 207 | struct cgroup *parent; /* my parent */ |
Arnd Bergmann | 2c392b8 | 2010-02-24 19:41:39 +0100 | [diff] [blame] | 208 | struct dentry __rcu *dentry; /* cgroup fs entry, RCU protected */ |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 209 | |
| 210 | /* Private pointers for each registered subsystem */ |
| 211 | struct cgroup_subsys_state *subsys[CGROUP_SUBSYS_COUNT]; |
| 212 | |
| 213 | struct cgroupfs_root *root; |
| 214 | struct cgroup *top_cgroup; |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 215 | |
| 216 | /* |
| 217 | * List of cg_cgroup_links pointing at css_sets with |
| 218 | * tasks in this cgroup. Protected by css_set_lock |
| 219 | */ |
| 220 | struct list_head css_sets; |
Paul Menage | 81a6a5c | 2007-10-18 23:39:38 -0700 | [diff] [blame] | 221 | |
| 222 | /* |
| 223 | * Linked list running through all cgroups that can |
| 224 | * potentially be reaped by the release agent. Protected by |
| 225 | * release_list_lock |
| 226 | */ |
| 227 | struct list_head release_list; |
Paul Menage | cc31edc | 2008-10-18 20:28:04 -0700 | [diff] [blame] | 228 | |
Ben Blum | 72a8cb3 | 2009-09-23 15:56:27 -0700 | [diff] [blame] | 229 | /* |
| 230 | * list of pidlists, up to two for each namespace (one for procs, one |
| 231 | * for tasks); created on demand. |
| 232 | */ |
| 233 | struct list_head pidlists; |
| 234 | struct mutex pidlist_mutex; |
Paul Menage | a47295e | 2009-01-07 18:07:44 -0800 | [diff] [blame] | 235 | |
| 236 | /* For RCU-protected deletion */ |
| 237 | struct rcu_head rcu_head; |
Kirill A. Shutemov | 0dea116 | 2010-03-10 15:22:20 -0800 | [diff] [blame] | 238 | |
| 239 | /* List of events which userspace want to recieve */ |
| 240 | struct list_head event_list; |
| 241 | spinlock_t event_list_lock; |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 242 | }; |
| 243 | |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 244 | /* |
| 245 | * A css_set is a structure holding pointers to a set of |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 246 | * cgroup_subsys_state objects. This saves space in the task struct |
| 247 | * object and speeds up fork()/exit(), since a single inc/dec and a |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 248 | * list_add()/del() can bump the reference count on the entire cgroup |
| 249 | * set for a task. |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 250 | */ |
| 251 | |
| 252 | struct css_set { |
| 253 | |
| 254 | /* Reference count */ |
Lai Jiangshan | 146aa1b | 2008-10-18 20:28:03 -0700 | [diff] [blame] | 255 | atomic_t refcount; |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 256 | |
| 257 | /* |
Li Zefan | 472b105 | 2008-04-29 01:00:11 -0700 | [diff] [blame] | 258 | * List running through all cgroup groups in the same hash |
| 259 | * slot. Protected by css_set_lock |
| 260 | */ |
| 261 | struct hlist_node hlist; |
| 262 | |
| 263 | /* |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 264 | * List running through all tasks using this cgroup |
| 265 | * group. Protected by css_set_lock |
| 266 | */ |
| 267 | struct list_head tasks; |
| 268 | |
| 269 | /* |
| 270 | * List of cg_cgroup_link objects on link chains from |
| 271 | * cgroups referenced from this css_set. Protected by |
| 272 | * css_set_lock |
| 273 | */ |
| 274 | struct list_head cg_links; |
| 275 | |
| 276 | /* |
| 277 | * Set of subsystem states, one for each subsystem. This array |
| 278 | * is immutable after creation apart from the init_css_set |
Ben Blum | cf5d594 | 2010-03-10 15:22:09 -0800 | [diff] [blame] | 279 | * during subsystem registration (at boot time) and modular subsystem |
| 280 | * loading/unloading. |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 281 | */ |
| 282 | struct cgroup_subsys_state *subsys[CGROUP_SUBSYS_COUNT]; |
Ben Blum | c378369 | 2009-09-23 15:56:29 -0700 | [diff] [blame] | 283 | |
| 284 | /* For RCU-protected deletion */ |
| 285 | struct rcu_head rcu_head; |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 286 | }; |
| 287 | |
Paul Menage | 9179656 | 2008-04-29 01:00:01 -0700 | [diff] [blame] | 288 | /* |
| 289 | * cgroup_map_cb is an abstract callback API for reporting map-valued |
| 290 | * control files |
| 291 | */ |
| 292 | |
| 293 | struct cgroup_map_cb { |
| 294 | int (*fill)(struct cgroup_map_cb *cb, const char *key, u64 value); |
| 295 | void *state; |
| 296 | }; |
| 297 | |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 298 | /* |
| 299 | * struct cftype: handler definitions for cgroup control files |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 300 | * |
| 301 | * When reading/writing to a file: |
Li Zefan | a043e3b | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 302 | * - the cgroup to use is file->f_dentry->d_parent->d_fsdata |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 303 | * - the 'cftype' of the file is file->f_dentry->d_fsdata |
| 304 | */ |
| 305 | |
| 306 | #define MAX_CFTYPE_NAME 64 |
| 307 | struct cftype { |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 308 | /* |
| 309 | * By convention, the name should begin with the name of the |
| 310 | * subsystem, followed by a period |
| 311 | */ |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 312 | char name[MAX_CFTYPE_NAME]; |
| 313 | int private; |
Li Zefan | 099fca3 | 2009-04-02 16:57:29 -0700 | [diff] [blame] | 314 | /* |
| 315 | * If not 0, file mode is set to this value, otherwise it will |
| 316 | * be figured out automatically |
| 317 | */ |
| 318 | mode_t mode; |
Paul Menage | db3b149 | 2008-07-25 01:46:58 -0700 | [diff] [blame] | 319 | |
| 320 | /* |
| 321 | * If non-zero, defines the maximum length of string that can |
| 322 | * be passed to write_string; defaults to 64 |
| 323 | */ |
| 324 | size_t max_write_len; |
| 325 | |
Paul Menage | ce16b49 | 2008-07-25 01:46:57 -0700 | [diff] [blame] | 326 | int (*open)(struct inode *inode, struct file *file); |
| 327 | ssize_t (*read)(struct cgroup *cgrp, struct cftype *cft, |
| 328 | struct file *file, |
| 329 | char __user *buf, size_t nbytes, loff_t *ppos); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 330 | /* |
Paul Menage | f4c753b | 2008-04-29 00:59:56 -0700 | [diff] [blame] | 331 | * read_u64() is a shortcut for the common case of returning a |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 332 | * single integer. Use it in place of read() |
| 333 | */ |
Paul Menage | ce16b49 | 2008-07-25 01:46:57 -0700 | [diff] [blame] | 334 | u64 (*read_u64)(struct cgroup *cgrp, struct cftype *cft); |
Paul Menage | 9179656 | 2008-04-29 01:00:01 -0700 | [diff] [blame] | 335 | /* |
Paul Menage | e73d2c6 | 2008-04-29 01:00:06 -0700 | [diff] [blame] | 336 | * read_s64() is a signed version of read_u64() |
| 337 | */ |
Paul Menage | ce16b49 | 2008-07-25 01:46:57 -0700 | [diff] [blame] | 338 | s64 (*read_s64)(struct cgroup *cgrp, struct cftype *cft); |
Paul Menage | e73d2c6 | 2008-04-29 01:00:06 -0700 | [diff] [blame] | 339 | /* |
Paul Menage | 9179656 | 2008-04-29 01:00:01 -0700 | [diff] [blame] | 340 | * read_map() is used for defining a map of key/value |
| 341 | * pairs. It should call cb->fill(cb, key, value) for each |
| 342 | * entry. The key/value pairs (and their ordering) should not |
| 343 | * change between reboots. |
| 344 | */ |
Paul Menage | ce16b49 | 2008-07-25 01:46:57 -0700 | [diff] [blame] | 345 | int (*read_map)(struct cgroup *cont, struct cftype *cft, |
| 346 | struct cgroup_map_cb *cb); |
Serge E. Hallyn | 29486df | 2008-04-29 01:00:14 -0700 | [diff] [blame] | 347 | /* |
| 348 | * read_seq_string() is used for outputting a simple sequence |
| 349 | * using seqfile. |
| 350 | */ |
Paul Menage | ce16b49 | 2008-07-25 01:46:57 -0700 | [diff] [blame] | 351 | int (*read_seq_string)(struct cgroup *cont, struct cftype *cft, |
| 352 | struct seq_file *m); |
Paul Menage | 9179656 | 2008-04-29 01:00:01 -0700 | [diff] [blame] | 353 | |
Paul Menage | ce16b49 | 2008-07-25 01:46:57 -0700 | [diff] [blame] | 354 | ssize_t (*write)(struct cgroup *cgrp, struct cftype *cft, |
| 355 | struct file *file, |
| 356 | const char __user *buf, size_t nbytes, loff_t *ppos); |
Paul Menage | 355e0c4 | 2007-10-18 23:39:33 -0700 | [diff] [blame] | 357 | |
| 358 | /* |
Paul Menage | f4c753b | 2008-04-29 00:59:56 -0700 | [diff] [blame] | 359 | * write_u64() is a shortcut for the common case of accepting |
Paul Menage | 355e0c4 | 2007-10-18 23:39:33 -0700 | [diff] [blame] | 360 | * a single integer (as parsed by simple_strtoull) from |
| 361 | * userspace. Use in place of write(); return 0 or error. |
| 362 | */ |
Paul Menage | ce16b49 | 2008-07-25 01:46:57 -0700 | [diff] [blame] | 363 | int (*write_u64)(struct cgroup *cgrp, struct cftype *cft, u64 val); |
Paul Menage | e73d2c6 | 2008-04-29 01:00:06 -0700 | [diff] [blame] | 364 | /* |
| 365 | * write_s64() is a signed version of write_u64() |
| 366 | */ |
Paul Menage | ce16b49 | 2008-07-25 01:46:57 -0700 | [diff] [blame] | 367 | int (*write_s64)(struct cgroup *cgrp, struct cftype *cft, s64 val); |
Paul Menage | 355e0c4 | 2007-10-18 23:39:33 -0700 | [diff] [blame] | 368 | |
Pavel Emelyanov | d447ea2 | 2008-04-29 01:00:08 -0700 | [diff] [blame] | 369 | /* |
Paul Menage | db3b149 | 2008-07-25 01:46:58 -0700 | [diff] [blame] | 370 | * write_string() is passed a nul-terminated kernelspace |
| 371 | * buffer of maximum length determined by max_write_len. |
| 372 | * Returns 0 or -ve error code. |
| 373 | */ |
| 374 | int (*write_string)(struct cgroup *cgrp, struct cftype *cft, |
| 375 | const char *buffer); |
| 376 | /* |
Pavel Emelyanov | d447ea2 | 2008-04-29 01:00:08 -0700 | [diff] [blame] | 377 | * trigger() callback can be used to get some kick from the |
| 378 | * userspace, when the actual string written is not important |
| 379 | * at all. The private field can be used to determine the |
| 380 | * kick type for multiplexing. |
| 381 | */ |
| 382 | int (*trigger)(struct cgroup *cgrp, unsigned int event); |
| 383 | |
Paul Menage | ce16b49 | 2008-07-25 01:46:57 -0700 | [diff] [blame] | 384 | int (*release)(struct inode *inode, struct file *file); |
Kirill A. Shutemov | 0dea116 | 2010-03-10 15:22:20 -0800 | [diff] [blame] | 385 | |
| 386 | /* |
| 387 | * register_event() callback will be used to add new userspace |
| 388 | * waiter for changes related to the cftype. Implement it if |
| 389 | * you want to provide this functionality. Use eventfd_signal() |
| 390 | * on eventfd to send notification to userspace. |
| 391 | */ |
| 392 | int (*register_event)(struct cgroup *cgrp, struct cftype *cft, |
| 393 | struct eventfd_ctx *eventfd, const char *args); |
| 394 | /* |
| 395 | * unregister_event() callback will be called when userspace |
| 396 | * closes the eventfd or on cgroup removing. |
| 397 | * This callback must be implemented, if you want provide |
| 398 | * notification functionality. |
Kirill A. Shutemov | 0dea116 | 2010-03-10 15:22:20 -0800 | [diff] [blame] | 399 | */ |
Kirill A. Shutemov | 907860e | 2010-05-26 14:42:46 -0700 | [diff] [blame] | 400 | void (*unregister_event)(struct cgroup *cgrp, struct cftype *cft, |
Kirill A. Shutemov | 0dea116 | 2010-03-10 15:22:20 -0800 | [diff] [blame] | 401 | struct eventfd_ctx *eventfd); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 402 | }; |
| 403 | |
Cliff Wickman | 31a7df0 | 2008-02-07 00:14:42 -0800 | [diff] [blame] | 404 | struct cgroup_scanner { |
| 405 | struct cgroup *cg; |
| 406 | int (*test_task)(struct task_struct *p, struct cgroup_scanner *scan); |
| 407 | void (*process_task)(struct task_struct *p, |
| 408 | struct cgroup_scanner *scan); |
| 409 | struct ptr_heap *heap; |
Li Zefan | bd1a8ab | 2009-04-02 16:57:50 -0700 | [diff] [blame] | 410 | void *data; |
Cliff Wickman | 31a7df0 | 2008-02-07 00:14:42 -0800 | [diff] [blame] | 411 | }; |
| 412 | |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 413 | /* |
| 414 | * Add a new file to the given cgroup directory. Should only be |
| 415 | * called by subsystems from within a populate() method |
| 416 | */ |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 417 | int cgroup_add_file(struct cgroup *cgrp, struct cgroup_subsys *subsys, |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 418 | const struct cftype *cft); |
| 419 | |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 420 | /* |
| 421 | * Add a set of new files to the given cgroup directory. Should |
| 422 | * only be called by subsystems from within a populate() method |
| 423 | */ |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 424 | int cgroup_add_files(struct cgroup *cgrp, |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 425 | struct cgroup_subsys *subsys, |
| 426 | const struct cftype cft[], |
| 427 | int count); |
| 428 | |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 429 | int cgroup_is_removed(const struct cgroup *cgrp); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 430 | |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 431 | int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 432 | |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 433 | int cgroup_task_count(const struct cgroup *cgrp); |
Paul Menage | bbcb81d | 2007-10-18 23:39:32 -0700 | [diff] [blame] | 434 | |
Grzegorz Nosek | 313e924 | 2009-04-02 16:57:23 -0700 | [diff] [blame] | 435 | /* Return true if cgrp is a descendant of the task's cgroup */ |
| 436 | int cgroup_is_descendant(const struct cgroup *cgrp, struct task_struct *task); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 437 | |
Thadeu Lima de Souza Cascardo | 21acb9c | 2009-02-04 10:12:08 +0100 | [diff] [blame] | 438 | /* |
KAMEZAWA Hiroyuki | 8870326 | 2009-07-29 15:04:06 -0700 | [diff] [blame] | 439 | * When the subsys has to access css and may add permanent refcnt to css, |
| 440 | * it should take care of racy conditions with rmdir(). Following set of |
| 441 | * functions, is for stop/restart rmdir if necessary. |
| 442 | * Because these will call css_get/put, "css" should be alive css. |
| 443 | * |
| 444 | * cgroup_exclude_rmdir(); |
| 445 | * ...do some jobs which may access arbitrary empty cgroup |
| 446 | * cgroup_release_and_wakeup_rmdir(); |
| 447 | * |
| 448 | * When someone removes a cgroup while cgroup_exclude_rmdir() holds it, |
| 449 | * it sleeps and cgroup_release_and_wakeup_rmdir() will wake him up. |
| 450 | */ |
| 451 | |
| 452 | void cgroup_exclude_rmdir(struct cgroup_subsys_state *css); |
| 453 | void cgroup_release_and_wakeup_rmdir(struct cgroup_subsys_state *css); |
| 454 | |
| 455 | /* |
Thadeu Lima de Souza Cascardo | 21acb9c | 2009-02-04 10:12:08 +0100 | [diff] [blame] | 456 | * Control Group subsystem type. |
| 457 | * See Documentation/cgroups/cgroups.txt for details |
| 458 | */ |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 459 | |
| 460 | struct cgroup_subsys { |
| 461 | struct cgroup_subsys_state *(*create)(struct cgroup_subsys *ss, |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 462 | struct cgroup *cgrp); |
KAMEZAWA Hiroyuki | ec64f51 | 2009-04-02 16:57:26 -0700 | [diff] [blame] | 463 | int (*pre_destroy)(struct cgroup_subsys *ss, struct cgroup *cgrp); |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 464 | void (*destroy)(struct cgroup_subsys *ss, struct cgroup *cgrp); |
Ben Blum | be367d0 | 2009-09-23 15:56:31 -0700 | [diff] [blame] | 465 | int (*can_attach)(struct cgroup_subsys *ss, struct cgroup *cgrp, |
| 466 | struct task_struct *tsk, bool threadgroup); |
Daisuke Nishimura | 2468c72 | 2010-03-10 15:22:03 -0800 | [diff] [blame] | 467 | void (*cancel_attach)(struct cgroup_subsys *ss, struct cgroup *cgrp, |
| 468 | struct task_struct *tsk, bool threadgroup); |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 469 | void (*attach)(struct cgroup_subsys *ss, struct cgroup *cgrp, |
Ben Blum | be367d0 | 2009-09-23 15:56:31 -0700 | [diff] [blame] | 470 | struct cgroup *old_cgrp, struct task_struct *tsk, |
| 471 | bool threadgroup); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 472 | void (*fork)(struct cgroup_subsys *ss, struct task_struct *task); |
| 473 | void (*exit)(struct cgroup_subsys *ss, struct task_struct *task); |
| 474 | int (*populate)(struct cgroup_subsys *ss, |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 475 | struct cgroup *cgrp); |
| 476 | void (*post_clone)(struct cgroup_subsys *ss, struct cgroup *cgrp); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 477 | void (*bind)(struct cgroup_subsys *ss, struct cgroup *root); |
Hugh Dickins | e599137 | 2009-01-06 14:39:22 -0800 | [diff] [blame] | 478 | |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 479 | int subsys_id; |
| 480 | int active; |
Paul Menage | 8bab8dd | 2008-04-04 14:29:57 -0700 | [diff] [blame] | 481 | int disabled; |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 482 | int early_init; |
KAMEZAWA Hiroyuki | 38460b4 | 2009-04-02 16:57:25 -0700 | [diff] [blame] | 483 | /* |
| 484 | * True if this subsys uses ID. ID is not available before cgroup_init() |
| 485 | * (not available in early_init time.) |
| 486 | */ |
| 487 | bool use_id; |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 488 | #define MAX_CGROUP_TYPE_NAMELEN 32 |
| 489 | const char *name; |
| 490 | |
Paul Menage | 999cd8a | 2009-01-07 18:08:36 -0800 | [diff] [blame] | 491 | /* |
| 492 | * Protects sibling/children links of cgroups in this |
| 493 | * hierarchy, plus protects which hierarchy (or none) the |
| 494 | * subsystem is a part of (i.e. root/sibling). To avoid |
| 495 | * potential deadlocks, the following operations should not be |
| 496 | * undertaken while holding any hierarchy_mutex: |
| 497 | * |
| 498 | * - allocating memory |
| 499 | * - initiating hotplug events |
| 500 | */ |
| 501 | struct mutex hierarchy_mutex; |
Li Zefan | cfebe56 | 2009-02-11 13:04:36 -0800 | [diff] [blame] | 502 | struct lock_class_key subsys_key; |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 503 | |
Paul Menage | 999cd8a | 2009-01-07 18:08:36 -0800 | [diff] [blame] | 504 | /* |
| 505 | * Link to parent, and list entry in parent's children. |
| 506 | * Protected by this->hierarchy_mutex and cgroup_lock() |
| 507 | */ |
| 508 | struct cgroupfs_root *root; |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 509 | struct list_head sibling; |
KAMEZAWA Hiroyuki | 38460b4 | 2009-04-02 16:57:25 -0700 | [diff] [blame] | 510 | /* used when use_id == true */ |
| 511 | struct idr idr; |
| 512 | spinlock_t id_lock; |
Ben Blum | e6a1105 | 2010-03-10 15:22:09 -0800 | [diff] [blame] | 513 | |
| 514 | /* should be defined only by modular subsystems */ |
| 515 | struct module *module; |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 516 | }; |
| 517 | |
| 518 | #define SUBSYS(_x) extern struct cgroup_subsys _x ## _subsys; |
| 519 | #include <linux/cgroup_subsys.h> |
| 520 | #undef SUBSYS |
| 521 | |
| 522 | static inline struct cgroup_subsys_state *cgroup_subsys_state( |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 523 | struct cgroup *cgrp, int subsys_id) |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 524 | { |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 525 | return cgrp->subsys[subsys_id]; |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 526 | } |
| 527 | |
Peter Zijlstra | dc61b1d | 2010-06-08 11:40:42 +0200 | [diff] [blame] | 528 | /* |
| 529 | * function to get the cgroup_subsys_state which allows for extra |
| 530 | * rcu_dereference_check() conditions, such as locks used during the |
| 531 | * cgroup_subsys::attach() methods. |
| 532 | */ |
| 533 | #define task_subsys_state_check(task, subsys_id, __c) \ |
| 534 | rcu_dereference_check(task->cgroups->subsys[subsys_id], \ |
| 535 | rcu_read_lock_held() || \ |
| 536 | lockdep_is_held(&task->alloc_lock) || \ |
| 537 | cgroup_lock_is_held() || (__c)) |
| 538 | |
| 539 | static inline struct cgroup_subsys_state * |
| 540 | task_subsys_state(struct task_struct *task, int subsys_id) |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 541 | { |
Peter Zijlstra | dc61b1d | 2010-06-08 11:40:42 +0200 | [diff] [blame] | 542 | return task_subsys_state_check(task, subsys_id, false); |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 543 | } |
| 544 | |
| 545 | static inline struct cgroup* task_cgroup(struct task_struct *task, |
| 546 | int subsys_id) |
| 547 | { |
| 548 | return task_subsys_state(task, subsys_id)->cgroup; |
| 549 | } |
| 550 | |
Serge E. Hallyn | e885dcd | 2008-07-25 01:47:06 -0700 | [diff] [blame] | 551 | int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *ss, |
| 552 | char *nodename); |
Paul Menage | 697f416 | 2007-10-18 23:39:34 -0700 | [diff] [blame] | 553 | |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 554 | /* A cgroup_iter should be treated as an opaque object */ |
| 555 | struct cgroup_iter { |
| 556 | struct list_head *cg_link; |
| 557 | struct list_head *task; |
| 558 | }; |
| 559 | |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 560 | /* |
| 561 | * To iterate across the tasks in a cgroup: |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 562 | * |
| 563 | * 1) call cgroup_iter_start to intialize an iterator |
| 564 | * |
| 565 | * 2) call cgroup_iter_next() to retrieve member tasks until it |
| 566 | * returns NULL or until you want to end the iteration |
| 567 | * |
| 568 | * 3) call cgroup_iter_end() to destroy the iterator. |
Cliff Wickman | 31a7df0 | 2008-02-07 00:14:42 -0800 | [diff] [blame] | 569 | * |
Paul Menage | d20a390 | 2009-04-02 16:57:22 -0700 | [diff] [blame] | 570 | * Or, call cgroup_scan_tasks() to iterate through every task in a |
| 571 | * cgroup - cgroup_scan_tasks() holds the css_set_lock when calling |
| 572 | * the test_task() callback, but not while calling the process_task() |
| 573 | * callback. |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 574 | */ |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 575 | void cgroup_iter_start(struct cgroup *cgrp, struct cgroup_iter *it); |
| 576 | struct task_struct *cgroup_iter_next(struct cgroup *cgrp, |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 577 | struct cgroup_iter *it); |
Li Zefan | ffd2d88 | 2008-02-23 15:24:09 -0800 | [diff] [blame] | 578 | void cgroup_iter_end(struct cgroup *cgrp, struct cgroup_iter *it); |
Cliff Wickman | 31a7df0 | 2008-02-07 00:14:42 -0800 | [diff] [blame] | 579 | int cgroup_scan_tasks(struct cgroup_scanner *scan); |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 580 | int cgroup_attach_task(struct cgroup *, struct task_struct *); |
Michael S. Tsirkin | 31583bb | 2010-09-09 16:37:37 -0700 | [diff] [blame] | 581 | int cgroup_attach_task_all(struct task_struct *from, struct task_struct *); |
| 582 | |
| 583 | static inline int cgroup_attach_task_current_cg(struct task_struct *tsk) |
| 584 | { |
| 585 | return cgroup_attach_task_all(current, tsk); |
| 586 | } |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 587 | |
KAMEZAWA Hiroyuki | 38460b4 | 2009-04-02 16:57:25 -0700 | [diff] [blame] | 588 | /* |
| 589 | * CSS ID is ID for cgroup_subsys_state structs under subsys. This only works |
| 590 | * if cgroup_subsys.use_id == true. It can be used for looking up and scanning. |
| 591 | * CSS ID is assigned at cgroup allocation (create) automatically |
| 592 | * and removed when subsys calls free_css_id() function. This is because |
| 593 | * the lifetime of cgroup_subsys_state is subsys's matter. |
| 594 | * |
| 595 | * Looking up and scanning function should be called under rcu_read_lock(). |
| 596 | * Taking cgroup_mutex()/hierarchy_mutex() is not necessary for following calls. |
| 597 | * But the css returned by this routine can be "not populated yet" or "being |
| 598 | * destroyed". The caller should check css and cgroup's status. |
| 599 | */ |
| 600 | |
| 601 | /* |
| 602 | * Typically Called at ->destroy(), or somewhere the subsys frees |
| 603 | * cgroup_subsys_state. |
| 604 | */ |
| 605 | void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css); |
| 606 | |
| 607 | /* Find a cgroup_subsys_state which has given ID */ |
| 608 | |
| 609 | struct cgroup_subsys_state *css_lookup(struct cgroup_subsys *ss, int id); |
| 610 | |
| 611 | /* |
| 612 | * Get a cgroup whose id is greater than or equal to id under tree of root. |
| 613 | * Returning a cgroup_subsys_state or NULL. |
| 614 | */ |
| 615 | struct cgroup_subsys_state *css_get_next(struct cgroup_subsys *ss, int id, |
| 616 | struct cgroup_subsys_state *root, int *foundid); |
| 617 | |
| 618 | /* Returns true if root is ancestor of cg */ |
| 619 | bool css_is_ancestor(struct cgroup_subsys_state *cg, |
KAMEZAWA Hiroyuki | 0b7f569 | 2009-04-02 16:57:38 -0700 | [diff] [blame] | 620 | const struct cgroup_subsys_state *root); |
KAMEZAWA Hiroyuki | 38460b4 | 2009-04-02 16:57:25 -0700 | [diff] [blame] | 621 | |
| 622 | /* Get id and depth of css */ |
| 623 | unsigned short css_id(struct cgroup_subsys_state *css); |
| 624 | unsigned short css_depth(struct cgroup_subsys_state *css); |
| 625 | |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 626 | #else /* !CONFIG_CGROUPS */ |
| 627 | |
| 628 | static inline int cgroup_init_early(void) { return 0; } |
| 629 | static inline int cgroup_init(void) { return 0; } |
Paul Menage | b4f48b6 | 2007-10-18 23:39:33 -0700 | [diff] [blame] | 630 | static inline void cgroup_fork(struct task_struct *p) {} |
| 631 | static inline void cgroup_fork_callbacks(struct task_struct *p) {} |
Paul Menage | 817929e | 2007-10-18 23:39:36 -0700 | [diff] [blame] | 632 | static inline void cgroup_post_fork(struct task_struct *p) {} |
Paul Menage | b4f48b6 | 2007-10-18 23:39:33 -0700 | [diff] [blame] | 633 | static inline void cgroup_exit(struct task_struct *p, int callbacks) {} |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 634 | |
| 635 | static inline void cgroup_lock(void) {} |
| 636 | static inline void cgroup_unlock(void) {} |
Balbir Singh | 846c7bb | 2007-10-18 23:39:44 -0700 | [diff] [blame] | 637 | static inline int cgroupstats_build(struct cgroupstats *stats, |
| 638 | struct dentry *dentry) |
| 639 | { |
| 640 | return -EINVAL; |
| 641 | } |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 642 | |
Sridhar Samudrala | d7926ee | 2010-05-30 22:24:39 +0200 | [diff] [blame] | 643 | /* No cgroups - nothing to do */ |
Michael S. Tsirkin | 31583bb | 2010-09-09 16:37:37 -0700 | [diff] [blame] | 644 | static inline int cgroup_attach_task_all(struct task_struct *from, |
| 645 | struct task_struct *t) |
| 646 | { |
| 647 | return 0; |
| 648 | } |
Sridhar Samudrala | d7926ee | 2010-05-30 22:24:39 +0200 | [diff] [blame] | 649 | static inline int cgroup_attach_task_current_cg(struct task_struct *t) |
| 650 | { |
| 651 | return 0; |
| 652 | } |
| 653 | |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 654 | #endif /* !CONFIG_CGROUPS */ |
| 655 | |
Paul Menage | ddbcc7e | 2007-10-18 23:39:30 -0700 | [diff] [blame] | 656 | #endif /* _LINUX_CGROUP_H */ |