1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_CGROUP_H
3 #define _LINUX_CGROUP_H
7 * Copyright (C) 2003 BULL SA
8 * Copyright (C) 2004-2006 Silicon Graphics, Inc.
12 #include <linux/sched.h>
13 #include <linux/cpumask.h>
14 #include <linux/nodemask.h>
15 #include <linux/rculist.h>
16 #include <linux/cgroupstats.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/ns_common.h>
23 #include <linux/nsproxy.h>
24 #include <linux/user_namespace.h>
25 #include <linux/refcount.h>
26 #include <linux/kernel_stat.h>
28 #include <linux/cgroup-defs.h>
30 struct kernel_clone_args
;
35 * All weight knobs on the default hierarhcy 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.
39 #define CGROUP_WEIGHT_MIN 1
40 #define CGROUP_WEIGHT_DFL 100
41 #define CGROUP_WEIGHT_MAX 10000
43 /* walk only threadgroup leaders */
44 #define CSS_TASK_ITER_PROCS (1U << 0)
45 /* walk all threaded css_sets in the domain */
46 #define CSS_TASK_ITER_THREADED (1U << 1)
49 #define CSS_TASK_ITER_SKIPPED (1U << 16)
51 /* a css_task_iter should be treated as an opaque object */
52 struct css_task_iter
{
53 struct cgroup_subsys
*ss
;
56 struct list_head
*cset_pos
;
57 struct list_head
*cset_head
;
59 struct list_head
*tcset_pos
;
60 struct list_head
*tcset_head
;
62 struct list_head
*task_pos
;
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 */
71 extern struct cgroup_root cgrp_dfl_root
;
72 extern struct css_set init_css_set
;
74 #define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys;
75 #include <linux/cgroup_subsys.h>
79 extern struct static_key_true _x ## _cgrp_subsys_enabled_key; \
80 extern struct static_key_true _x ## _cgrp_subsys_on_dfl_key;
81 #include <linux/cgroup_subsys.h>
85 * cgroup_subsys_enabled - fast test on whether a subsys is enabled
86 * @ss: subsystem in question
88 #define cgroup_subsys_enabled(ss) \
89 static_branch_likely(&ss ## _enabled_key)
92 * cgroup_subsys_on_dfl - fast test on whether a subsys is on default hierarchy
93 * @ss: subsystem in question
95 #define cgroup_subsys_on_dfl(ss) \
96 static_branch_likely(&ss ## _on_dfl_key)
98 bool css_has_online_children(struct cgroup_subsys_state
*css
);
99 struct cgroup_subsys_state
*css_from_id(int id
, struct cgroup_subsys
*ss
);
100 struct cgroup_subsys_state
*cgroup_e_css(struct cgroup
*cgroup
,
101 struct cgroup_subsys
*ss
);
102 struct cgroup_subsys_state
*cgroup_get_e_css(struct cgroup
*cgroup
,
103 struct cgroup_subsys
*ss
);
104 struct cgroup_subsys_state
*css_tryget_online_from_dir(struct dentry
*dentry
,
105 struct cgroup_subsys
*ss
);
107 struct cgroup
*cgroup_get_from_path(const char *path
);
108 struct cgroup
*cgroup_get_from_fd(int fd
);
110 int cgroup_attach_task_all(struct task_struct
*from
, struct task_struct
*);
111 int cgroup_transfer_tasks(struct cgroup
*to
, struct cgroup
*from
);
113 int cgroup_add_dfl_cftypes(struct cgroup_subsys
*ss
, struct cftype
*cfts
);
114 int cgroup_add_legacy_cftypes(struct cgroup_subsys
*ss
, struct cftype
*cfts
);
115 int cgroup_rm_cftypes(struct cftype
*cfts
);
116 void cgroup_file_notify(struct cgroup_file
*cfile
);
118 int task_cgroup_path(struct task_struct
*task
, char *buf
, size_t buflen
);
119 int cgroupstats_build(struct cgroupstats
*stats
, struct dentry
*dentry
);
120 int proc_cgroup_show(struct seq_file
*m
, struct pid_namespace
*ns
,
121 struct pid
*pid
, struct task_struct
*tsk
);
123 void cgroup_fork(struct task_struct
*p
);
124 extern int cgroup_can_fork(struct task_struct
*p
,
125 struct kernel_clone_args
*kargs
);
126 extern void cgroup_cancel_fork(struct task_struct
*p
,
127 struct kernel_clone_args
*kargs
);
128 extern void cgroup_post_fork(struct task_struct
*p
,
129 struct kernel_clone_args
*kargs
);
130 void cgroup_exit(struct task_struct
*p
);
131 void cgroup_release(struct task_struct
*p
);
132 void cgroup_free(struct task_struct
*p
);
134 int cgroup_init_early(void);
135 int cgroup_init(void);
137 int cgroup_parse_float(const char *input
, unsigned dec_shift
, s64
*v
);
140 * Iteration helpers and macros.
143 struct cgroup_subsys_state
*css_next_child(struct cgroup_subsys_state
*pos
,
144 struct cgroup_subsys_state
*parent
);
145 struct cgroup_subsys_state
*css_next_descendant_pre(struct cgroup_subsys_state
*pos
,
146 struct cgroup_subsys_state
*css
);
147 struct cgroup_subsys_state
*css_rightmost_descendant(struct cgroup_subsys_state
*pos
);
148 struct cgroup_subsys_state
*css_next_descendant_post(struct cgroup_subsys_state
*pos
,
149 struct cgroup_subsys_state
*css
);
151 struct task_struct
*cgroup_taskset_first(struct cgroup_taskset
*tset
,
152 struct cgroup_subsys_state
**dst_cssp
);
153 struct task_struct
*cgroup_taskset_next(struct cgroup_taskset
*tset
,
154 struct cgroup_subsys_state
**dst_cssp
);
156 void css_task_iter_start(struct cgroup_subsys_state
*css
, unsigned int flags
,
157 struct css_task_iter
*it
);
158 struct task_struct
*css_task_iter_next(struct css_task_iter
*it
);
159 void css_task_iter_end(struct css_task_iter
*it
);
162 * css_for_each_child - iterate through children of a css
163 * @pos: the css * to use as the loop cursor
164 * @parent: css whose children to walk
166 * Walk @parent's children. Must be called under rcu_read_lock().
168 * If a subsystem synchronizes ->css_online() and the start of iteration, a
169 * css which finished ->css_online() is guaranteed to be visible in the
170 * future iterations and will stay visible until the last reference is put.
171 * A css which hasn't finished ->css_online() or already finished
172 * ->css_offline() may show up during traversal. It's each subsystem's
173 * responsibility to synchronize against on/offlining.
175 * It is allowed to temporarily drop RCU read lock during iteration. The
176 * caller is responsible for ensuring that @pos remains accessible until
177 * the start of the next iteration by, for example, bumping the css refcnt.
179 #define css_for_each_child(pos, parent) \
180 for ((pos) = css_next_child(NULL, (parent)); (pos); \
181 (pos) = css_next_child((pos), (parent)))
184 * css_for_each_descendant_pre - pre-order walk of a css's descendants
185 * @pos: the css * to use as the loop cursor
186 * @root: css whose descendants to walk
188 * Walk @root's descendants. @root is included in the iteration and the
189 * first node to be visited. Must be called under rcu_read_lock().
191 * If a subsystem synchronizes ->css_online() and the start of iteration, a
192 * css which finished ->css_online() is guaranteed to be visible in the
193 * future iterations and will stay visible until the last reference is put.
194 * A css which hasn't finished ->css_online() or already finished
195 * ->css_offline() may show up during traversal. It's each subsystem's
196 * responsibility to synchronize against on/offlining.
198 * For example, the following guarantees that a descendant can't escape
199 * state updates of its ancestors.
203 * Lock @css's parent and @css;
204 * Inherit state from the parent;
208 * my_update_state(@css)
210 * css_for_each_descendant_pre(@pos, @css) {
213 * Update @css's state;
215 * Verify @pos is alive and inherit state from its parent;
220 * As long as the inheriting step, including checking the parent state, is
221 * enclosed inside @pos locking, double-locking the parent isn't necessary
222 * while inheriting. The state update to the parent is guaranteed to be
223 * visible by walking order and, as long as inheriting operations to the
224 * same @pos are atomic to each other, multiple updates racing each other
225 * still result in the correct state. It's guaranateed that at least one
226 * inheritance happens for any css after the latest update to its parent.
228 * If checking parent's state requires locking the parent, each inheriting
229 * iteration should lock and unlock both @pos->parent and @pos.
231 * Alternatively, a subsystem may choose to use a single global lock to
232 * synchronize ->css_online() and ->css_offline() against tree-walking
235 * It is allowed to temporarily drop RCU read lock during iteration. The
236 * caller is responsible for ensuring that @pos remains accessible until
237 * the start of the next iteration by, for example, bumping the css refcnt.
239 #define css_for_each_descendant_pre(pos, css) \
240 for ((pos) = css_next_descendant_pre(NULL, (css)); (pos); \
241 (pos) = css_next_descendant_pre((pos), (css)))
244 * css_for_each_descendant_post - post-order walk of a css's descendants
245 * @pos: the css * to use as the loop cursor
246 * @css: css whose descendants to walk
248 * Similar to css_for_each_descendant_pre() but performs post-order
249 * traversal instead. @root is included in the iteration and the last
250 * node to be visited.
252 * If a subsystem synchronizes ->css_online() and the start of iteration, a
253 * css which finished ->css_online() is guaranteed to be visible in the
254 * future iterations and will stay visible until the last reference is put.
255 * A css which hasn't finished ->css_online() or already finished
256 * ->css_offline() may show up during traversal. It's each subsystem's
257 * responsibility to synchronize against on/offlining.
259 * Note that the walk visibility guarantee example described in pre-order
260 * walk doesn't apply the same to post-order walks.
262 #define css_for_each_descendant_post(pos, css) \
263 for ((pos) = css_next_descendant_post(NULL, (css)); (pos); \
264 (pos) = css_next_descendant_post((pos), (css)))
267 * cgroup_taskset_for_each - iterate cgroup_taskset
268 * @task: the loop cursor
269 * @dst_css: the destination css
270 * @tset: taskset to iterate
272 * @tset may contain multiple tasks and they may belong to multiple
275 * On the v2 hierarchy, there may be tasks from multiple processes and they
276 * may not share the source or destination csses.
278 * On traditional hierarchies, when there are multiple tasks in @tset, if a
279 * task of a process is in @tset, all tasks of the process are in @tset.
280 * Also, all are guaranteed to share the same source and destination csses.
282 * Iteration is not in any specific order.
284 #define cgroup_taskset_for_each(task, dst_css, tset) \
285 for ((task) = cgroup_taskset_first((tset), &(dst_css)); \
287 (task) = cgroup_taskset_next((tset), &(dst_css)))
290 * cgroup_taskset_for_each_leader - iterate group leaders in a cgroup_taskset
291 * @leader: the loop cursor
292 * @dst_css: the destination css
293 * @tset: taskset to iterate
295 * Iterate threadgroup leaders of @tset. For single-task migrations, @tset
296 * may not contain any.
298 #define cgroup_taskset_for_each_leader(leader, dst_css, tset) \
299 for ((leader) = cgroup_taskset_first((tset), &(dst_css)); \
301 (leader) = cgroup_taskset_next((tset), &(dst_css))) \
302 if ((leader) != (leader)->group_leader) \
310 static inline u64
cgroup_id(const struct cgroup
*cgrp
)
316 * css_get - obtain a reference on the specified css
319 * The caller must already have a reference.
321 static inline void css_get(struct cgroup_subsys_state
*css
)
323 if (!(css
->flags
& CSS_NO_REF
))
324 percpu_ref_get(&css
->refcnt
);
328 * css_get_many - obtain references on the specified css
330 * @n: number of references to get
332 * The caller must already have a reference.
334 static inline void css_get_many(struct cgroup_subsys_state
*css
, unsigned int n
)
336 if (!(css
->flags
& CSS_NO_REF
))
337 percpu_ref_get_many(&css
->refcnt
, n
);
341 * css_tryget - try to obtain a reference on the specified css
344 * Obtain a reference on @css unless it already has reached zero and is
345 * being released. This function doesn't care whether @css is on or
346 * offline. The caller naturally needs to ensure that @css is accessible
347 * but doesn't have to be holding a reference on it - IOW, RCU protected
348 * access is good enough for this function. Returns %true if a reference
349 * count was successfully obtained; %false otherwise.
351 static inline bool css_tryget(struct cgroup_subsys_state
*css
)
353 if (!(css
->flags
& CSS_NO_REF
))
354 return percpu_ref_tryget(&css
->refcnt
);
359 * css_tryget_online - try to obtain a reference on the specified css if online
362 * Obtain a reference on @css if it's online. The caller naturally needs
363 * to ensure that @css is accessible but doesn't have to be holding a
364 * reference on it - IOW, RCU protected access is good enough for this
365 * function. Returns %true if a reference count was successfully obtained;
368 static inline bool css_tryget_online(struct cgroup_subsys_state
*css
)
370 if (!(css
->flags
& CSS_NO_REF
))
371 return percpu_ref_tryget_live(&css
->refcnt
);
376 * css_is_dying - test whether the specified css is dying
379 * Test whether @css is in the process of offlining or already offline. In
380 * most cases, ->css_online() and ->css_offline() callbacks should be
381 * enough; however, the actual offline operations are RCU delayed and this
382 * test returns %true also when @css is scheduled to be offlined.
384 * This is useful, for example, when the use case requires synchronous
385 * behavior with respect to cgroup removal. cgroup removal schedules css
386 * offlining but the css can seem alive while the operation is being
387 * delayed. If the delay affects user visible semantics, this test can be
388 * used to resolve the situation.
390 static inline bool css_is_dying(struct cgroup_subsys_state
*css
)
392 return !(css
->flags
& CSS_NO_REF
) && percpu_ref_is_dying(&css
->refcnt
);
396 * css_put - put a css reference
399 * Put a reference obtained via css_get() and css_tryget_online().
401 static inline void css_put(struct cgroup_subsys_state
*css
)
403 if (!(css
->flags
& CSS_NO_REF
))
404 percpu_ref_put(&css
->refcnt
);
408 * css_put_many - put css references
410 * @n: number of references to put
412 * Put references obtained via css_get() and css_tryget_online().
414 static inline void css_put_many(struct cgroup_subsys_state
*css
, unsigned int n
)
416 if (!(css
->flags
& CSS_NO_REF
))
417 percpu_ref_put_many(&css
->refcnt
, n
);
420 static inline void cgroup_get(struct cgroup
*cgrp
)
422 css_get(&cgrp
->self
);
425 static inline bool cgroup_tryget(struct cgroup
*cgrp
)
427 return css_tryget(&cgrp
->self
);
430 static inline void cgroup_put(struct cgroup
*cgrp
)
432 css_put(&cgrp
->self
);
436 * task_css_set_check - obtain a task's css_set with extra access conditions
437 * @task: the task to obtain css_set for
438 * @__c: extra condition expression to be passed to rcu_dereference_check()
440 * A task's css_set is RCU protected, initialized and exited while holding
441 * task_lock(), and can only be modified while holding both cgroup_mutex
442 * and task_lock() while the task is alive. This macro verifies that the
443 * caller is inside proper critical section and returns @task's css_set.
445 * The caller can also specify additional allowed conditions via @__c, such
446 * as locks used during the cgroup_subsys::attach() methods.
448 #ifdef CONFIG_PROVE_RCU
449 extern struct mutex cgroup_mutex
;
450 extern spinlock_t css_set_lock
;
451 #define task_css_set_check(task, __c) \
452 rcu_dereference_check((task)->cgroups, \
453 lockdep_is_held(&cgroup_mutex) || \
454 lockdep_is_held(&css_set_lock) || \
455 ((task)->flags & PF_EXITING) || (__c))
457 #define task_css_set_check(task, __c) \
458 rcu_dereference((task)->cgroups)
462 * task_css_check - obtain css for (task, subsys) w/ extra access conds
463 * @task: the target task
464 * @subsys_id: the target subsystem ID
465 * @__c: extra condition expression to be passed to rcu_dereference_check()
467 * Return the cgroup_subsys_state for the (@task, @subsys_id) pair. The
468 * synchronization rules are the same as task_css_set_check().
470 #define task_css_check(task, subsys_id, __c) \
471 task_css_set_check((task), (__c))->subsys[(subsys_id)]
474 * task_css_set - obtain a task's css_set
475 * @task: the task to obtain css_set for
477 * See task_css_set_check().
479 static inline struct css_set
*task_css_set(struct task_struct
*task
)
481 return task_css_set_check(task
, false);
485 * task_css - obtain css for (task, subsys)
486 * @task: the target task
487 * @subsys_id: the target subsystem ID
489 * See task_css_check().
491 static inline struct cgroup_subsys_state
*task_css(struct task_struct
*task
,
494 return task_css_check(task
, subsys_id
, false);
498 * task_get_css - find and get the css for (task, subsys)
499 * @task: the target task
500 * @subsys_id: the target subsystem ID
502 * Find the css for the (@task, @subsys_id) combination, increment a
503 * reference on and return it. This function is guaranteed to return a
504 * valid css. The returned css may already have been offlined.
506 static inline struct cgroup_subsys_state
*
507 task_get_css(struct task_struct
*task
, int subsys_id
)
509 struct cgroup_subsys_state
*css
;
513 css
= task_css(task
, subsys_id
);
515 * Can't use css_tryget_online() here. A task which has
516 * PF_EXITING set may stay associated with an offline css.
517 * If such task calls this function, css_tryget_online()
520 if (likely(css_tryget(css
)))
529 * task_css_is_root - test whether a task belongs to the root css
530 * @task: the target task
531 * @subsys_id: the target subsystem ID
533 * Test whether @task belongs to the root css on the specified subsystem.
534 * May be invoked in any context.
536 static inline bool task_css_is_root(struct task_struct
*task
, int subsys_id
)
538 return task_css_check(task
, subsys_id
, true) ==
539 init_css_set
.subsys
[subsys_id
];
542 static inline struct cgroup
*task_cgroup(struct task_struct
*task
,
545 return task_css(task
, subsys_id
)->cgroup
;
548 static inline struct cgroup
*task_dfl_cgroup(struct task_struct
*task
)
550 return task_css_set(task
)->dfl_cgrp
;
553 static inline struct cgroup
*cgroup_parent(struct cgroup
*cgrp
)
555 struct cgroup_subsys_state
*parent_css
= cgrp
->self
.parent
;
558 return container_of(parent_css
, struct cgroup
, self
);
563 * cgroup_is_descendant - test ancestry
564 * @cgrp: the cgroup to be tested
565 * @ancestor: possible ancestor of @cgrp
567 * Test whether @cgrp is a descendant of @ancestor. It also returns %true
568 * if @cgrp == @ancestor. This function is safe to call as long as @cgrp
569 * and @ancestor are accessible.
571 static inline bool cgroup_is_descendant(struct cgroup
*cgrp
,
572 struct cgroup
*ancestor
)
574 if (cgrp
->root
!= ancestor
->root
|| cgrp
->level
< ancestor
->level
)
576 return cgrp
->ancestor_ids
[ancestor
->level
] == cgroup_id(ancestor
);
580 * cgroup_ancestor - find ancestor of cgroup
581 * @cgrp: cgroup to find ancestor of
582 * @ancestor_level: level of ancestor to find starting from root
584 * Find ancestor of cgroup at specified level starting from root if it exists
585 * and return pointer to it. Return NULL if @cgrp doesn't have ancestor at
588 * This function is safe to call as long as @cgrp is accessible.
590 static inline struct cgroup
*cgroup_ancestor(struct cgroup
*cgrp
,
593 if (cgrp
->level
< ancestor_level
)
595 while (cgrp
&& cgrp
->level
> ancestor_level
)
596 cgrp
= cgroup_parent(cgrp
);
601 * task_under_cgroup_hierarchy - test task's membership of cgroup ancestry
602 * @task: the task to be tested
603 * @ancestor: possible ancestor of @task's cgroup
605 * Tests whether @task's default cgroup hierarchy is a descendant of @ancestor.
606 * It follows all the same rules as cgroup_is_descendant, and only applies
607 * to the default hierarchy.
609 static inline bool task_under_cgroup_hierarchy(struct task_struct
*task
,
610 struct cgroup
*ancestor
)
612 struct css_set
*cset
= task_css_set(task
);
614 return cgroup_is_descendant(cset
->dfl_cgrp
, ancestor
);
617 /* no synchronization, the result can only be used as a hint */
618 static inline bool cgroup_is_populated(struct cgroup
*cgrp
)
620 return cgrp
->nr_populated_csets
+ cgrp
->nr_populated_domain_children
+
621 cgrp
->nr_populated_threaded_children
;
624 /* returns ino associated with a cgroup */
625 static inline ino_t
cgroup_ino(struct cgroup
*cgrp
)
627 return kernfs_ino(cgrp
->kn
);
630 /* cft/css accessors for cftype->write() operation */
631 static inline struct cftype
*of_cft(struct kernfs_open_file
*of
)
636 struct cgroup_subsys_state
*of_css(struct kernfs_open_file
*of
);
638 /* cft/css accessors for cftype->seq_*() operations */
639 static inline struct cftype
*seq_cft(struct seq_file
*seq
)
641 return of_cft(seq
->private);
644 static inline struct cgroup_subsys_state
*seq_css(struct seq_file
*seq
)
646 return of_css(seq
->private);
650 * Name / path handling functions. All are thin wrappers around the kernfs
651 * counterparts and can be called under any context.
654 static inline int cgroup_name(struct cgroup
*cgrp
, char *buf
, size_t buflen
)
656 return kernfs_name(cgrp
->kn
, buf
, buflen
);
659 static inline int cgroup_path(struct cgroup
*cgrp
, char *buf
, size_t buflen
)
661 return kernfs_path(cgrp
->kn
, buf
, buflen
);
664 static inline void pr_cont_cgroup_name(struct cgroup
*cgrp
)
666 pr_cont_kernfs_name(cgrp
->kn
);
669 static inline void pr_cont_cgroup_path(struct cgroup
*cgrp
)
671 pr_cont_kernfs_path(cgrp
->kn
);
674 static inline struct psi_group
*cgroup_psi(struct cgroup
*cgrp
)
679 static inline void cgroup_init_kthreadd(void)
682 * kthreadd is inherited by all kthreads, keep it in the root so
683 * that the new kthreads are guaranteed to stay in the root until
684 * initialization is finished.
686 current
->no_cgroup_migration
= 1;
689 static inline void cgroup_kthread_ready(void)
692 * This kthread finished initialization. The creator should have
693 * set PF_NO_SETAFFINITY if this kthread should stay in the root.
695 current
->no_cgroup_migration
= 0;
698 void cgroup_path_from_kernfs_id(u64 id
, char *buf
, size_t buflen
);
699 #else /* !CONFIG_CGROUPS */
701 struct cgroup_subsys_state
;
704 static inline u64
cgroup_id(const struct cgroup
*cgrp
) { return 1; }
705 static inline void css_get(struct cgroup_subsys_state
*css
) {}
706 static inline void css_put(struct cgroup_subsys_state
*css
) {}
707 static inline int cgroup_attach_task_all(struct task_struct
*from
,
708 struct task_struct
*t
) { return 0; }
709 static inline int cgroupstats_build(struct cgroupstats
*stats
,
710 struct dentry
*dentry
) { return -EINVAL
; }
712 static inline void cgroup_fork(struct task_struct
*p
) {}
713 static inline int cgroup_can_fork(struct task_struct
*p
,
714 struct kernel_clone_args
*kargs
) { return 0; }
715 static inline void cgroup_cancel_fork(struct task_struct
*p
,
716 struct kernel_clone_args
*kargs
) {}
717 static inline void cgroup_post_fork(struct task_struct
*p
,
718 struct kernel_clone_args
*kargs
) {}
719 static inline void cgroup_exit(struct task_struct
*p
) {}
720 static inline void cgroup_release(struct task_struct
*p
) {}
721 static inline void cgroup_free(struct task_struct
*p
) {}
723 static inline int cgroup_init_early(void) { return 0; }
724 static inline int cgroup_init(void) { return 0; }
725 static inline void cgroup_init_kthreadd(void) {}
726 static inline void cgroup_kthread_ready(void) {}
728 static inline struct cgroup
*cgroup_parent(struct cgroup
*cgrp
)
733 static inline struct psi_group
*cgroup_psi(struct cgroup
*cgrp
)
738 static inline bool task_under_cgroup_hierarchy(struct task_struct
*task
,
739 struct cgroup
*ancestor
)
744 static inline void cgroup_path_from_kernfs_id(u64 id
, char *buf
, size_t buflen
)
746 #endif /* !CONFIG_CGROUPS */
748 #ifdef CONFIG_CGROUPS
750 * cgroup scalable recursive statistics.
752 void cgroup_rstat_updated(struct cgroup
*cgrp
, int cpu
);
753 void cgroup_rstat_flush(struct cgroup
*cgrp
);
754 void cgroup_rstat_flush_irqsafe(struct cgroup
*cgrp
);
755 void cgroup_rstat_flush_hold(struct cgroup
*cgrp
);
756 void cgroup_rstat_flush_release(void);
759 * Basic resource stats.
761 #ifdef CONFIG_CGROUP_CPUACCT
762 void cpuacct_charge(struct task_struct
*tsk
, u64 cputime
);
763 void cpuacct_account_field(struct task_struct
*tsk
, int index
, u64 val
);
765 static inline void cpuacct_charge(struct task_struct
*tsk
, u64 cputime
) {}
766 static inline void cpuacct_account_field(struct task_struct
*tsk
, int index
,
770 void __cgroup_account_cputime(struct cgroup
*cgrp
, u64 delta_exec
);
771 void __cgroup_account_cputime_field(struct cgroup
*cgrp
,
772 enum cpu_usage_stat index
, u64 delta_exec
);
774 static inline void cgroup_account_cputime(struct task_struct
*task
,
779 cpuacct_charge(task
, delta_exec
);
782 cgrp
= task_dfl_cgroup(task
);
783 if (cgroup_parent(cgrp
))
784 __cgroup_account_cputime(cgrp
, delta_exec
);
788 static inline void cgroup_account_cputime_field(struct task_struct
*task
,
789 enum cpu_usage_stat index
,
794 cpuacct_account_field(task
, index
, delta_exec
);
797 cgrp
= task_dfl_cgroup(task
);
798 if (cgroup_parent(cgrp
))
799 __cgroup_account_cputime_field(cgrp
, index
, delta_exec
);
803 #else /* CONFIG_CGROUPS */
805 static inline void cgroup_account_cputime(struct task_struct
*task
,
807 static inline void cgroup_account_cputime_field(struct task_struct
*task
,
808 enum cpu_usage_stat index
,
811 #endif /* CONFIG_CGROUPS */
814 * sock->sk_cgrp_data handling. For more info, see sock_cgroup_data
815 * definition in cgroup-defs.h.
817 #ifdef CONFIG_SOCK_CGROUP_DATA
819 #if defined(CONFIG_CGROUP_NET_PRIO) || defined(CONFIG_CGROUP_NET_CLASSID)
820 extern spinlock_t cgroup_sk_update_lock
;
823 void cgroup_sk_alloc_disable(void);
824 void cgroup_sk_alloc(struct sock_cgroup_data
*skcd
);
825 void cgroup_sk_clone(struct sock_cgroup_data
*skcd
);
826 void cgroup_sk_free(struct sock_cgroup_data
*skcd
);
828 static inline struct cgroup
*sock_cgroup_ptr(struct sock_cgroup_data
*skcd
)
830 #if defined(CONFIG_CGROUP_NET_PRIO) || defined(CONFIG_CGROUP_NET_CLASSID)
834 * @skcd->val is 64bit but the following is safe on 32bit too as we
835 * just need the lower ulong to be written and read atomically.
837 v
= READ_ONCE(skcd
->val
);
840 return &cgrp_dfl_root
.cgrp
;
842 return (struct cgroup
*)(unsigned long)v
?: &cgrp_dfl_root
.cgrp
;
844 return (struct cgroup
*)(unsigned long)skcd
->val
;
848 #else /* CONFIG_CGROUP_DATA */
850 static inline void cgroup_sk_alloc(struct sock_cgroup_data
*skcd
) {}
851 static inline void cgroup_sk_clone(struct sock_cgroup_data
*skcd
) {}
852 static inline void cgroup_sk_free(struct sock_cgroup_data
*skcd
) {}
854 #endif /* CONFIG_CGROUP_DATA */
856 struct cgroup_namespace
{
858 struct user_namespace
*user_ns
;
859 struct ucounts
*ucounts
;
860 struct css_set
*root_cset
;
863 extern struct cgroup_namespace init_cgroup_ns
;
865 #ifdef CONFIG_CGROUPS
867 void free_cgroup_ns(struct cgroup_namespace
*ns
);
869 struct cgroup_namespace
*copy_cgroup_ns(unsigned long flags
,
870 struct user_namespace
*user_ns
,
871 struct cgroup_namespace
*old_ns
);
873 int cgroup_path_ns(struct cgroup
*cgrp
, char *buf
, size_t buflen
,
874 struct cgroup_namespace
*ns
);
876 #else /* !CONFIG_CGROUPS */
878 static inline void free_cgroup_ns(struct cgroup_namespace
*ns
) { }
879 static inline struct cgroup_namespace
*
880 copy_cgroup_ns(unsigned long flags
, struct user_namespace
*user_ns
,
881 struct cgroup_namespace
*old_ns
)
886 #endif /* !CONFIG_CGROUPS */
888 static inline void get_cgroup_ns(struct cgroup_namespace
*ns
)
891 refcount_inc(&ns
->ns
.count
);
894 static inline void put_cgroup_ns(struct cgroup_namespace
*ns
)
896 if (ns
&& refcount_dec_and_test(&ns
->ns
.count
))
900 #ifdef CONFIG_CGROUPS
902 void cgroup_enter_frozen(void);
903 void cgroup_leave_frozen(bool always_leave
);
904 void cgroup_update_frozen(struct cgroup
*cgrp
);
905 void cgroup_freeze(struct cgroup
*cgrp
, bool freeze
);
906 void cgroup_freezer_migrate_task(struct task_struct
*task
, struct cgroup
*src
,
909 static inline bool cgroup_task_freeze(struct task_struct
*task
)
913 if (task
->flags
& PF_KTHREAD
)
917 ret
= test_bit(CGRP_FREEZE
, &task_dfl_cgroup(task
)->flags
);
923 static inline bool cgroup_task_frozen(struct task_struct
*task
)
928 #else /* !CONFIG_CGROUPS */
930 static inline void cgroup_enter_frozen(void) { }
931 static inline void cgroup_leave_frozen(bool always_leave
) { }
932 static inline bool cgroup_task_freeze(struct task_struct
*task
)
936 static inline bool cgroup_task_frozen(struct task_struct
*task
)
941 #endif /* !CONFIG_CGROUPS */
943 #ifdef CONFIG_CGROUP_BPF
944 static inline void cgroup_bpf_get(struct cgroup
*cgrp
)
946 percpu_ref_get(&cgrp
->bpf
.refcnt
);
949 static inline void cgroup_bpf_put(struct cgroup
*cgrp
)
951 percpu_ref_put(&cgrp
->bpf
.refcnt
);
954 #else /* CONFIG_CGROUP_BPF */
956 static inline void cgroup_bpf_get(struct cgroup
*cgrp
) {}
957 static inline void cgroup_bpf_put(struct cgroup
*cgrp
) {}
959 #endif /* CONFIG_CGROUP_BPF */
961 #endif /* _LINUX_CGROUP_H */