1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_CGROUP_H
3#define _LINUX_CGROUP_H
4/*
5 * cgroup interface
6 *
7 * Copyright (C) 2003 BULL SA
8 * Copyright (C) 2004-2006 Silicon Graphics, Inc.
9 *
10 */
11
12#include <linux/sched.h>
13#include <linux/nodemask.h>
14#include <linux/list.h>
15#include <linux/rculist.h>
16#include <linux/cgroupstats.h>
17#include <linux/fs.h>
18#include <linux/seq_file.h>
19#include <linux/kernfs.h>
20#include <linux/jump_label.h>
21#include <linux/types.h>
22#include <linux/notifier.h>
23#include <linux/ns_common.h>
24#include <linux/nsproxy.h>
25#include <linux/user_namespace.h>
26#include <linux/refcount.h>
27#include <linux/kernel_stat.h>
28
29#include <linux/cgroup-defs.h>
30#include <linux/cgroup_namespace.h>
31
32struct kernel_clone_args;
33
34/*
35 * All weight knobs on the default hierarchy should use the following min,
36 * default and max values. The default value is the logarithmic center of
37 * MIN and MAX and allows 100x to be expressed in both directions.
38 */
39#define CGROUP_WEIGHT_MIN 1
40#define CGROUP_WEIGHT_DFL 100
41#define CGROUP_WEIGHT_MAX 10000
42
43#ifdef CONFIG_CGROUPS
44
45enum css_task_iter_flags {
46 CSS_TASK_ITER_PROCS = (1U << 0), /* walk only threadgroup leaders */
47 CSS_TASK_ITER_THREADED = (1U << 1), /* walk all threaded css_sets in the domain */
48 CSS_TASK_ITER_SKIPPED = (1U << 16), /* internal flags */
49};
50
51/* a css_task_iter should be treated as an opaque object */
52struct css_task_iter {
53 struct cgroup_subsys *ss;
54 unsigned int flags;
55
56 struct list_head *cset_pos;
57 struct list_head *cset_head;
58
59 struct list_head *tcset_pos;
60 struct list_head *tcset_head;
61
62 struct list_head *task_pos;
63
64 struct list_head *cur_tasks_head;
65 struct css_set *cur_cset;
66 struct css_set *cur_dcset;
67 struct task_struct *cur_task;
68 struct list_head iters_node; /* css_set->task_iters */
69};
70
71enum cgroup_lifetime_events {
72 CGROUP_LIFETIME_ONLINE,
73 CGROUP_LIFETIME_OFFLINE,
74};
75
76extern struct file_system_type cgroup_fs_type;
77extern struct cgroup_root cgrp_dfl_root;
78extern struct css_set init_css_set;
79extern spinlock_t css_set_lock;
80extern struct blocking_notifier_head cgroup_lifetime_notifier;
81
82#define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys;
83#include <linux/cgroup_subsys.h>
84#undef SUBSYS
85
86#define SUBSYS(_x) \
87 extern struct static_key_true _x ## _cgrp_subsys_enabled_key; \
88 extern struct static_key_true _x ## _cgrp_subsys_on_dfl_key;
89#include <linux/cgroup_subsys.h>
90#undef SUBSYS
91
92/**
93 * cgroup_subsys_enabled - fast test on whether a subsys is enabled
94 * @ss: subsystem in question
95 */
96#define cgroup_subsys_enabled(ss) \
97 static_branch_likely(&ss ## _enabled_key)
98
99/**
100 * cgroup_subsys_on_dfl - fast test on whether a subsys is on default hierarchy
101 * @ss: subsystem in question
102 */
103#define cgroup_subsys_on_dfl(ss) \
104 static_branch_likely(&ss ## _on_dfl_key)
105
106bool css_has_online_children(struct cgroup_subsys_state *css);
107struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss);
108struct cgroup_subsys_state *cgroup_e_css(struct cgroup *cgroup,
109 struct cgroup_subsys *ss);
110struct cgroup_subsys_state *cgroup_get_e_css(struct cgroup *cgroup,
111 struct cgroup_subsys *ss);
112struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry,
113 struct cgroup_subsys *ss);
114
115struct cgroup *cgroup_get_from_path(const char *path);
116struct cgroup *cgroup_get_from_fd(int fd);
117struct cgroup *cgroup_v1v2_get_from_fd(int fd);
118
119int cgroup_attach_task_all(struct task_struct *from, struct task_struct *);
120int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from);
121
122int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
123int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
124int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
125int cgroup_rm_cftypes(struct cftype *cfts);
126void cgroup_file_notify(struct cgroup_file *cfile);
127void cgroup_file_show(struct cgroup_file *cfile, bool show);
128
129int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry);
130int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns,
131 struct pid *pid, struct task_struct *tsk);
132
133void cgroup_fork(struct task_struct *p);
134extern int cgroup_can_fork(struct task_struct *p,
135 struct kernel_clone_args *kargs);
136extern void cgroup_cancel_fork(struct task_struct *p,
137 struct kernel_clone_args *kargs);
138extern void cgroup_post_fork(struct task_struct *p,
139 struct kernel_clone_args *kargs);
140void cgroup_exit(struct task_struct *p);
141void cgroup_release(struct task_struct *p);
142void cgroup_free(struct task_struct *p);
143
144int cgroup_init_early(void);
145int cgroup_init(void);
146
147int cgroup_parse_float(const char *input, unsigned dec_shift, s64 *v);
148
149/*
150 * Iteration helpers and macros.
151 */
152
153struct cgroup_subsys_state *css_next_child(struct cgroup_subsys_state *pos,
154 struct cgroup_subsys_state *parent);
155struct cgroup_subsys_state *css_next_descendant_pre(struct cgroup_subsys_state *pos,
156 struct cgroup_subsys_state *css);
157struct cgroup_subsys_state *css_rightmost_descendant(struct cgroup_subsys_state *pos);
158struct cgroup_subsys_state *css_next_descendant_post(struct cgroup_subsys_state *pos,
159 struct cgroup_subsys_state *css);
160
161struct task_struct *cgroup_taskset_first(struct cgroup_taskset *tset,
162 struct cgroup_subsys_state **dst_cssp);
163struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset,
164 struct cgroup_subsys_state **dst_cssp);
165
166void css_task_iter_start(struct cgroup_subsys_state *css, unsigned int flags,
167 struct css_task_iter *it);
168struct task_struct *css_task_iter_next(struct css_task_iter *it);
169void css_task_iter_end(struct css_task_iter *it);
170
171/**
172 * css_for_each_child - iterate through children of a css
173 * @pos: the css * to use as the loop cursor
174 * @parent: css whose children to walk
175 *
176 * Walk @parent's children. Must be called under rcu_read_lock().
177 *
178 * If a subsystem synchronizes ->css_online() and the start of iteration, a
179 * css which finished ->css_online() is guaranteed to be visible in the
180 * future iterations and will stay visible until the last reference is put.
181 * A css which hasn't finished ->css_online() or already finished
182 * ->css_offline() may show up during traversal. It's each subsystem's
183 * responsibility to synchronize against on/offlining.
184 *
185 * It is allowed to temporarily drop RCU read lock during iteration. The
186 * caller is responsible for ensuring that @pos remains accessible until
187 * the start of the next iteration by, for example, bumping the css refcnt.
188 */
189#define css_for_each_child(pos, parent) \
190 for ((pos) = css_next_child(NULL, (parent)); (pos); \
191 (pos) = css_next_child((pos), (parent)))
192
193/**
194 * css_for_each_descendant_pre - pre-order walk of a css's descendants
195 * @pos: the css * to use as the loop cursor
196 * @root: css whose descendants to walk
197 *
198 * Walk @root's descendants. @root is included in the iteration and the
199 * first node to be visited. Must be called under rcu_read_lock().
200 *
201 * If a subsystem synchronizes ->css_online() and the start of iteration, a
202 * css which finished ->css_online() is guaranteed to be visible in the
203 * future iterations and will stay visible until the last reference is put.
204 * A css which hasn't finished ->css_online() or already finished
205 * ->css_offline() may show up during traversal. It's each subsystem's
206 * responsibility to synchronize against on/offlining.
207 *
208 * For example, the following guarantees that a descendant can't escape
209 * state updates of its ancestors.
210 *
211 * my_online(@css)
212 * {
213 * Lock @css's parent and @css;
214 * Inherit state from the parent;
215 * Unlock both.
216 * }
217 *
218 * my_update_state(@css)
219 * {
220 * css_for_each_descendant_pre(@pos, @css) {
221 * Lock @pos;
222 * if (@pos == @css)
223 * Update @css's state;
224 * else
225 * Verify @pos is alive and inherit state from its parent;
226 * Unlock @pos;
227 * }
228 * }
229 *
230 * As long as the inheriting step, including checking the parent state, is
231 * enclosed inside @pos locking, double-locking the parent isn't necessary
232 * while inheriting. The state update to the parent is guaranteed to be
233 * visible by walking order and, as long as inheriting operations to the
234 * same @pos are atomic to each other, multiple updates racing each other
235 * still result in the correct state. It's guaranateed that at least one
236 * inheritance happens for any css after the latest update to its parent.
237 *
238 * If checking parent's state requires locking the parent, each inheriting
239 * iteration should lock and unlock both @pos->parent and @pos.
240 *
241 * Alternatively, a subsystem may choose to use a single global lock to
242 * synchronize ->css_online() and ->css_offline() against tree-walking
243 * operations.
244 *
245 * It is allowed to temporarily drop RCU read lock during iteration. The
246 * caller is responsible for ensuring that @pos remains accessible until
247 * the start of the next iteration by, for example, bumping the css refcnt.
248 */
249#define css_for_each_descendant_pre(pos, css) \
250 for ((pos) = css_next_descendant_pre(NULL, (css)); (pos); \
251 (pos) = css_next_descendant_pre((pos), (css)))
252
253/**
254 * css_for_each_descendant_post - post-order walk of a css's descendants
255 * @pos: the css * to use as the loop cursor
256 * @css: css whose descendants to walk
257 *
258 * Similar to css_for_each_descendant_pre() but performs post-order
259 * traversal instead. @root is included in the iteration and the last
260 * node to be visited.
261 *
262 * If a subsystem synchronizes ->css_online() and the start of iteration, a
263 * css which finished ->css_online() is guaranteed to be visible in the
264 * future iterations and will stay visible until the last reference is put.
265 * A css which hasn't finished ->css_online() or already finished
266 * ->css_offline() may show up during traversal. It's each subsystem's
267 * responsibility to synchronize against on/offlining.
268 *
269 * Note that the walk visibility guarantee example described in pre-order
270 * walk doesn't apply the same to post-order walks.
271 */
272#define css_for_each_descendant_post(pos, css) \
273 for ((pos) = css_next_descendant_post(NULL, (css)); (pos); \
274 (pos) = css_next_descendant_post((pos), (css)))
275
276/**
277 * cgroup_taskset_for_each - iterate cgroup_taskset
278 * @task: the loop cursor
279 * @dst_css: the destination css
280 * @tset: taskset to iterate
281 *
282 * @tset may contain multiple tasks and they may belong to multiple
283 * processes.
284 *
285 * On the v2 hierarchy, there may be tasks from multiple processes and they
286 * may not share the source or destination csses.
287 *
288 * On traditional hierarchies, when there are multiple tasks in @tset, if a
289 * task of a process is in @tset, all tasks of the process are in @tset.
290 * Also, all are guaranteed to share the same source and destination csses.
291 *
292 * Iteration is not in any specific order.
293 */
294#define cgroup_taskset_for_each(task, dst_css, tset) \
295 for ((task) = cgroup_taskset_first((tset), &(dst_css)); \
296 (task); \
297 (task) = cgroup_taskset_next((tset), &(dst_css)))
298
299/**
300 * cgroup_taskset_for_each_leader - iterate group leaders in a cgroup_taskset
301 * @leader: the loop cursor
302 * @dst_css: the destination css
303 * @tset: taskset to iterate
304 *
305 * Iterate threadgroup leaders of @tset. For single-task migrations, @tset
306 * may not contain any.
307 */
308#define cgroup_taskset_for_each_leader(leader, dst_css, tset) \
309 for ((leader) = cgroup_taskset_first((tset), &(dst_css)); \
310 (leader); \
311 (leader) = cgroup_taskset_next((tset), &(dst_css))) \
312 if ((leader) != (leader)->group_leader) \
313 ; \
314 else
315
316/*
317 * Inline functions.
318 */
319
320#ifdef CONFIG_DEBUG_CGROUP_REF
321void css_get(struct cgroup_subsys_state *css);
322void css_get_many(struct cgroup_subsys_state *css, unsigned int n);
323bool css_tryget(struct cgroup_subsys_state *css);
324bool css_tryget_online(struct cgroup_subsys_state *css);
325void css_put(struct cgroup_subsys_state *css);
326void css_put_many(struct cgroup_subsys_state *css, unsigned int n);
327#else
328#define CGROUP_REF_FN_ATTRS static inline
329#define CGROUP_REF_EXPORT(fn)
330#include <linux/cgroup_refcnt.h>
331#endif
332
333static inline u64 cgroup_id(const struct cgroup *cgrp)
334{
335 return cgrp->kn->id;
336}
337
338/**
339 * css_is_dying - test whether the specified css is dying
340 * @css: target css
341 *
342 * Test whether @css is in the process of offlining or already offline. In
343 * most cases, ->css_online() and ->css_offline() callbacks should be
344 * enough; however, the actual offline operations are RCU delayed and this
345 * test returns %true also when @css is scheduled to be offlined.
346 *
347 * This is useful, for example, when the use case requires synchronous
348 * behavior with respect to cgroup removal. cgroup removal schedules css
349 * offlining but the css can seem alive while the operation is being
350 * delayed. If the delay affects user visible semantics, this test can be
351 * used to resolve the situation.
352 */
353static inline bool css_is_dying(struct cgroup_subsys_state *css)
354{
355 return css->flags & CSS_DYING;
356}
357
358static inline bool css_is_online(struct cgroup_subsys_state *css)
359{
360 return css->flags & CSS_ONLINE;
361}
362
363static inline bool css_is_self(struct cgroup_subsys_state *css)
364{
365 if (css == &css->cgroup->self) {
366 /* cgroup::self should not have subsystem association */
367 WARN_ON(css->ss != NULL);
368 return true;
369 }
370
371 return false;
372}
373
374static inline void cgroup_get(struct cgroup *cgrp)
375{
376 css_get(css: &cgrp->self);
377}
378
379static inline bool cgroup_tryget(struct cgroup *cgrp)
380{
381 return css_tryget(css: &cgrp->self);
382}
383
384static inline void cgroup_put(struct cgroup *cgrp)
385{
386 css_put(css: &cgrp->self);
387}
388
389extern struct mutex cgroup_mutex;
390
391static inline void cgroup_lock(void)
392{
393 mutex_lock(lock: &cgroup_mutex);
394}
395
396static inline void cgroup_unlock(void)
397{
398 mutex_unlock(lock: &cgroup_mutex);
399}
400
401/**
402 * task_css_set_check - obtain a task's css_set with extra access conditions
403 * @task: the task to obtain css_set for
404 * @__c: extra condition expression to be passed to rcu_dereference_check()
405 *
406 * A task's css_set is RCU protected, initialized and exited while holding
407 * task_lock(), and can only be modified while holding both cgroup_mutex
408 * and task_lock() while the task is alive. This macro verifies that the
409 * caller is inside proper critical section and returns @task's css_set.
410 *
411 * The caller can also specify additional allowed conditions via @__c, such
412 * as locks used during the cgroup_subsys::attach() methods.
413 */
414#ifdef CONFIG_PROVE_RCU
415#define task_css_set_check(task, __c) \
416 rcu_dereference_check((task)->cgroups, \
417 rcu_read_lock_sched_held() || \
418 lockdep_is_held(&cgroup_mutex) || \
419 lockdep_is_held(&css_set_lock) || \
420 ((task)->flags & PF_EXITING) || (__c))
421#else
422#define task_css_set_check(task, __c) \
423 rcu_dereference((task)->cgroups)
424#endif
425
426/**
427 * task_css_check - obtain css for (task, subsys) w/ extra access conds
428 * @task: the target task
429 * @subsys_id: the target subsystem ID
430 * @__c: extra condition expression to be passed to rcu_dereference_check()
431 *
432 * Return the cgroup_subsys_state for the (@task, @subsys_id) pair. The
433 * synchronization rules are the same as task_css_set_check().
434 */
435#define task_css_check(task, subsys_id, __c) \
436 task_css_set_check((task), (__c))->subsys[(subsys_id)]
437
438/**
439 * task_css_set - obtain a task's css_set
440 * @task: the task to obtain css_set for
441 *
442 * See task_css_set_check().
443 */
444static inline struct css_set *task_css_set(struct task_struct *task)
445{
446 return task_css_set_check(task, false);
447}
448
449/**
450 * task_css - obtain css for (task, subsys)
451 * @task: the target task
452 * @subsys_id: the target subsystem ID
453 *
454 * See task_css_check().
455 */
456static inline struct cgroup_subsys_state *task_css(struct task_struct *task,
457 int subsys_id)
458{
459 return task_css_check(task, subsys_id, false);
460}
461
462/**
463 * task_get_css - find and get the css for (task, subsys)
464 * @task: the target task
465 * @subsys_id: the target subsystem ID
466 *
467 * Find the css for the (@task, @subsys_id) combination, increment a
468 * reference on and return it. This function is guaranteed to return a
469 * valid css. The returned css may already have been offlined.
470 */
471static inline struct cgroup_subsys_state *
472task_get_css(struct task_struct *task, int subsys_id)
473{
474 struct cgroup_subsys_state *css;
475
476 rcu_read_lock();
477 while (true) {
478 css = task_css(task, subsys_id);
479 /*
480 * Can't use css_tryget_online() here. A task which has
481 * PF_EXITING set may stay associated with an offline css.
482 * If such task calls this function, css_tryget_online()
483 * will keep failing.
484 */
485 if (likely(css_tryget(css)))
486 break;
487 cpu_relax();
488 }
489 rcu_read_unlock();
490 return css;
491}
492
493/**
494 * task_css_is_root - test whether a task belongs to the root css
495 * @task: the target task
496 * @subsys_id: the target subsystem ID
497 *
498 * Test whether @task belongs to the root css on the specified subsystem.
499 * May be invoked in any context.
500 */
501static inline bool task_css_is_root(struct task_struct *task, int subsys_id)
502{
503 return task_css_check(task, subsys_id, true) ==
504 init_css_set.subsys[subsys_id];
505}
506
507static inline struct cgroup *task_cgroup(struct task_struct *task,
508 int subsys_id)
509{
510 return task_css(task, subsys_id)->cgroup;
511}
512
513static inline struct cgroup *task_dfl_cgroup(struct task_struct *task)
514{
515 return task_css_set(task)->dfl_cgrp;
516}
517
518static inline struct cgroup *cgroup_parent(struct cgroup *cgrp)
519{
520 struct cgroup_subsys_state *parent_css = cgrp->self.parent;
521
522 if (parent_css)
523 return container_of(parent_css, struct cgroup, self);
524 return NULL;
525}
526
527/**
528 * cgroup_is_descendant - test ancestry
529 * @cgrp: the cgroup to be tested
530 * @ancestor: possible ancestor of @cgrp
531 *
532 * Test whether @cgrp is a descendant of @ancestor. It also returns %true
533 * if @cgrp == @ancestor. This function is safe to call as long as @cgrp
534 * and @ancestor are accessible.
535 */
536static inline bool cgroup_is_descendant(struct cgroup *cgrp,
537 struct cgroup *ancestor)
538{
539 if (cgrp->root != ancestor->root || cgrp->level < ancestor->level)
540 return false;
541 return cgrp->ancestors[ancestor->level] == ancestor;
542}
543
544/**
545 * cgroup_ancestor - find ancestor of cgroup
546 * @cgrp: cgroup to find ancestor of
547 * @ancestor_level: level of ancestor to find starting from root
548 *
549 * Find ancestor of cgroup at specified level starting from root if it exists
550 * and return pointer to it. Return NULL if @cgrp doesn't have ancestor at
551 * @ancestor_level.
552 *
553 * This function is safe to call as long as @cgrp is accessible.
554 */
555static inline struct cgroup *cgroup_ancestor(struct cgroup *cgrp,
556 int ancestor_level)
557{
558 if (ancestor_level < 0 || ancestor_level > cgrp->level)
559 return NULL;
560 return cgrp->ancestors[ancestor_level];
561}
562
563/**
564 * task_under_cgroup_hierarchy - test task's membership of cgroup ancestry
565 * @task: the task to be tested
566 * @ancestor: possible ancestor of @task's cgroup
567 *
568 * Tests whether @task's default cgroup hierarchy is a descendant of @ancestor.
569 * It follows all the same rules as cgroup_is_descendant, and only applies
570 * to the default hierarchy.
571 */
572static inline bool task_under_cgroup_hierarchy(struct task_struct *task,
573 struct cgroup *ancestor)
574{
575 struct css_set *cset = task_css_set(task);
576
577 return cgroup_is_descendant(cgrp: cset->dfl_cgrp, ancestor);
578}
579
580/* no synchronization, the result can only be used as a hint */
581static inline bool cgroup_is_populated(struct cgroup *cgrp)
582{
583 return cgrp->nr_populated_csets + cgrp->nr_populated_domain_children +
584 cgrp->nr_populated_threaded_children;
585}
586
587/* returns ino associated with a cgroup */
588static inline ino_t cgroup_ino(struct cgroup *cgrp)
589{
590 return kernfs_ino(kn: cgrp->kn);
591}
592
593/* cft/css accessors for cftype->write() operation */
594static inline struct cftype *of_cft(struct kernfs_open_file *of)
595{
596 return of->kn->priv;
597}
598
599struct cgroup_subsys_state *of_css(struct kernfs_open_file *of);
600
601/* cft/css accessors for cftype->seq_*() operations */
602static inline struct cftype *seq_cft(struct seq_file *seq)
603{
604 return of_cft(of: seq->private);
605}
606
607static inline struct cgroup_subsys_state *seq_css(struct seq_file *seq)
608{
609 return of_css(of: seq->private);
610}
611
612/*
613 * Name / path handling functions. All are thin wrappers around the kernfs
614 * counterparts and can be called under any context.
615 */
616
617static inline int cgroup_name(struct cgroup *cgrp, char *buf, size_t buflen)
618{
619 return kernfs_name(kn: cgrp->kn, buf, buflen);
620}
621
622static inline int cgroup_path(struct cgroup *cgrp, char *buf, size_t buflen)
623{
624 return kernfs_path(kn: cgrp->kn, buf, buflen);
625}
626
627static inline void pr_cont_cgroup_name(struct cgroup *cgrp)
628{
629 pr_cont_kernfs_name(kn: cgrp->kn);
630}
631
632static inline void pr_cont_cgroup_path(struct cgroup *cgrp)
633{
634 pr_cont_kernfs_path(kn: cgrp->kn);
635}
636
637bool cgroup_psi_enabled(void);
638
639static inline void cgroup_init_kthreadd(void)
640{
641 /*
642 * kthreadd is inherited by all kthreads, keep it in the root so
643 * that the new kthreads are guaranteed to stay in the root until
644 * initialization is finished.
645 */
646 current->no_cgroup_migration = 1;
647}
648
649static inline void cgroup_kthread_ready(void)
650{
651 /*
652 * This kthread finished initialization. The creator should have
653 * set PF_NO_SETAFFINITY if this kthread should stay in the root.
654 */
655 current->no_cgroup_migration = 0;
656}
657
658void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen);
659struct cgroup *__cgroup_get_from_id(u64 id);
660struct cgroup *cgroup_get_from_id(u64 id);
661#else /* !CONFIG_CGROUPS */
662
663struct cgroup_subsys_state;
664struct cgroup;
665
666static inline u64 cgroup_id(const struct cgroup *cgrp) { return 1; }
667static inline void css_get(struct cgroup_subsys_state *css) {}
668static inline void css_put(struct cgroup_subsys_state *css) {}
669static inline void cgroup_lock(void) {}
670static inline void cgroup_unlock(void) {}
671static inline int cgroup_attach_task_all(struct task_struct *from,
672 struct task_struct *t) { return 0; }
673static inline int cgroupstats_build(struct cgroupstats *stats,
674 struct dentry *dentry) { return -EINVAL; }
675
676static inline void cgroup_fork(struct task_struct *p) {}
677static inline int cgroup_can_fork(struct task_struct *p,
678 struct kernel_clone_args *kargs) { return 0; }
679static inline void cgroup_cancel_fork(struct task_struct *p,
680 struct kernel_clone_args *kargs) {}
681static inline void cgroup_post_fork(struct task_struct *p,
682 struct kernel_clone_args *kargs) {}
683static inline void cgroup_exit(struct task_struct *p) {}
684static inline void cgroup_release(struct task_struct *p) {}
685static inline void cgroup_free(struct task_struct *p) {}
686
687static inline int cgroup_init_early(void) { return 0; }
688static inline int cgroup_init(void) { return 0; }
689static inline void cgroup_init_kthreadd(void) {}
690static inline void cgroup_kthread_ready(void) {}
691
692static inline struct cgroup *cgroup_parent(struct cgroup *cgrp)
693{
694 return NULL;
695}
696
697static inline bool cgroup_psi_enabled(void)
698{
699 return false;
700}
701
702static inline bool task_under_cgroup_hierarchy(struct task_struct *task,
703 struct cgroup *ancestor)
704{
705 return true;
706}
707
708static inline void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen)
709{}
710#endif /* !CONFIG_CGROUPS */
711
712#ifdef CONFIG_CGROUPS
713/*
714 * cgroup scalable recursive statistics.
715 */
716void css_rstat_updated(struct cgroup_subsys_state *css, int cpu);
717void css_rstat_flush(struct cgroup_subsys_state *css);
718
719/*
720 * Basic resource stats.
721 */
722#ifdef CONFIG_CGROUP_CPUACCT
723void cpuacct_charge(struct task_struct *tsk, u64 cputime);
724void cpuacct_account_field(struct task_struct *tsk, int index, u64 val);
725#else
726static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
727static inline void cpuacct_account_field(struct task_struct *tsk, int index,
728 u64 val) {}
729#endif
730
731void __cgroup_account_cputime(struct cgroup *cgrp, u64 delta_exec);
732void __cgroup_account_cputime_field(struct cgroup *cgrp,
733 enum cpu_usage_stat index, u64 delta_exec);
734
735static inline void cgroup_account_cputime(struct task_struct *task,
736 u64 delta_exec)
737{
738 struct cgroup *cgrp;
739
740 cpuacct_charge(tsk: task, cputime: delta_exec);
741
742 cgrp = task_dfl_cgroup(task);
743 if (cgroup_parent(cgrp))
744 __cgroup_account_cputime(cgrp, delta_exec);
745}
746
747static inline void cgroup_account_cputime_field(struct task_struct *task,
748 enum cpu_usage_stat index,
749 u64 delta_exec)
750{
751 struct cgroup *cgrp;
752
753 cpuacct_account_field(tsk: task, index, val: delta_exec);
754
755 cgrp = task_dfl_cgroup(task);
756 if (cgroup_parent(cgrp))
757 __cgroup_account_cputime_field(cgrp, index, delta_exec);
758}
759
760#else /* CONFIG_CGROUPS */
761
762static inline void cgroup_account_cputime(struct task_struct *task,
763 u64 delta_exec) {}
764static inline void cgroup_account_cputime_field(struct task_struct *task,
765 enum cpu_usage_stat index,
766 u64 delta_exec) {}
767
768#endif /* CONFIG_CGROUPS */
769
770/*
771 * sock->sk_cgrp_data handling. For more info, see sock_cgroup_data
772 * definition in cgroup-defs.h.
773 */
774#ifdef CONFIG_SOCK_CGROUP_DATA
775
776void cgroup_sk_alloc(struct sock_cgroup_data *skcd);
777void cgroup_sk_clone(struct sock_cgroup_data *skcd);
778void cgroup_sk_free(struct sock_cgroup_data *skcd);
779
780static inline struct cgroup *sock_cgroup_ptr(struct sock_cgroup_data *skcd)
781{
782 return skcd->cgroup;
783}
784
785#else /* CONFIG_CGROUP_DATA */
786
787static inline void cgroup_sk_alloc(struct sock_cgroup_data *skcd) {}
788static inline void cgroup_sk_clone(struct sock_cgroup_data *skcd) {}
789static inline void cgroup_sk_free(struct sock_cgroup_data *skcd) {}
790
791#endif /* CONFIG_CGROUP_DATA */
792
793#ifdef CONFIG_CGROUPS
794
795void cgroup_enter_frozen(void);
796void cgroup_leave_frozen(bool always_leave);
797void cgroup_update_frozen(struct cgroup *cgrp);
798void cgroup_freeze(struct cgroup *cgrp, bool freeze);
799void cgroup_freezer_migrate_task(struct task_struct *task, struct cgroup *src,
800 struct cgroup *dst);
801
802static inline bool cgroup_task_frozen(struct task_struct *task)
803{
804 return task->frozen;
805}
806
807#else /* !CONFIG_CGROUPS */
808
809static inline void cgroup_enter_frozen(void) { }
810static inline void cgroup_leave_frozen(bool always_leave) { }
811static inline bool cgroup_task_frozen(struct task_struct *task)
812{
813 return false;
814}
815
816#endif /* !CONFIG_CGROUPS */
817
818#ifdef CONFIG_CGROUP_BPF
819static inline void cgroup_bpf_get(struct cgroup *cgrp)
820{
821 percpu_ref_get(&cgrp->bpf.refcnt);
822}
823
824static inline void cgroup_bpf_put(struct cgroup *cgrp)
825{
826 percpu_ref_put(&cgrp->bpf.refcnt);
827}
828
829#else /* CONFIG_CGROUP_BPF */
830
831static inline void cgroup_bpf_get(struct cgroup *cgrp) {}
832static inline void cgroup_bpf_put(struct cgroup *cgrp) {}
833
834#endif /* CONFIG_CGROUP_BPF */
835
836struct cgroup *task_get_cgroup1(struct task_struct *tsk, int hierarchy_id);
837
838struct cgroup_of_peak *of_peak(struct kernfs_open_file *of);
839
840#endif /* _LINUX_CGROUP_H */
841