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>
33 * All weight knobs on the default hierarhcy should use the following min,
34 * default and max values. The default value is the logarithmic center of
35 * MIN and MAX and allows 100x to be expressed in both directions.
37 #define CGROUP_WEIGHT_MIN 1
38 #define CGROUP_WEIGHT_DFL 100
39 #define CGROUP_WEIGHT_MAX 10000
41 /* walk only threadgroup leaders */
42 #define CSS_TASK_ITER_PROCS (1U << 0)
43 /* walk all threaded css_sets in the domain */
44 #define CSS_TASK_ITER_THREADED (1U << 1)
47 #define CSS_TASK_ITER_SKIPPED (1U << 16)
49 /* a css_task_iter should be treated as an opaque object */
50 struct css_task_iter
{
51 struct cgroup_subsys
*ss
;
54 struct list_head
*cset_pos
;
55 struct list_head
*cset_head
;
57 struct list_head
*tcset_pos
;
58 struct list_head
*tcset_head
;
60 struct list_head
*task_pos
;
61 struct list_head
*tasks_head
;
62 struct list_head
*mg_tasks_head
;
63 struct list_head
*dying_tasks_head
;
65 struct list_head
*cur_tasks_head
;
66 struct css_set
*cur_cset
;
67 struct css_set
*cur_dcset
;
68 struct task_struct
*cur_task
;
69 struct list_head iters_node
; /* css_set->task_iters */
72 extern struct cgroup_root cgrp_dfl_root
;
73 extern struct css_set init_css_set
;
75 #define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys;
76 #include <linux/cgroup_subsys.h>
80 extern struct static_key_true _x ## _cgrp_subsys_enabled_key; \
81 extern struct static_key_true _x ## _cgrp_subsys_on_dfl_key;
82 #include <linux/cgroup_subsys.h>
86 * cgroup_subsys_enabled - fast test on whether a subsys is enabled
87 * @ss: subsystem in question
89 #define cgroup_subsys_enabled(ss) \
90 static_branch_likely(&ss ## _enabled_key)
93 * cgroup_subsys_on_dfl - fast test on whether a subsys is on default hierarchy
94 * @ss: subsystem in question
96 #define cgroup_subsys_on_dfl(ss) \
97 static_branch_likely(&ss ## _on_dfl_key)
99 bool css_has_online_children(struct cgroup_subsys_state
*css
);
100 struct cgroup_subsys_state
*css_from_id(int id
, struct cgroup_subsys
*ss
);
101 struct cgroup_subsys_state
*cgroup_e_css(struct cgroup
*cgroup
,
102 struct cgroup_subsys
*ss
);
103 struct cgroup_subsys_state
*cgroup_get_e_css(struct cgroup
*cgroup
,
104 struct cgroup_subsys
*ss
);
105 struct cgroup_subsys_state
*css_tryget_online_from_dir(struct dentry
*dentry
,
106 struct cgroup_subsys
*ss
);
108 struct cgroup
*cgroup_get_from_path(const char *path
);
109 struct cgroup
*cgroup_get_from_fd(int fd
);
111 int cgroup_attach_task_all(struct task_struct
*from
, struct task_struct
*);
112 int cgroup_transfer_tasks(struct cgroup
*to
, struct cgroup
*from
);
114 int cgroup_add_dfl_cftypes(struct cgroup_subsys
*ss
, struct cftype
*cfts
);
115 int cgroup_add_legacy_cftypes(struct cgroup_subsys
*ss
, struct cftype
*cfts
);
116 int cgroup_rm_cftypes(struct cftype
*cfts
);
117 void cgroup_file_notify(struct cgroup_file
*cfile
);
119 int task_cgroup_path(struct task_struct
*task
, char *buf
, size_t buflen
);
120 int cgroupstats_build(struct cgroupstats
*stats
, struct dentry
*dentry
);
121 int proc_cgroup_show(struct seq_file
*m
, struct pid_namespace
*ns
,
122 struct pid
*pid
, struct task_struct
*tsk
);
124 void cgroup_fork(struct task_struct
*p
);
125 extern int cgroup_can_fork(struct task_struct
*p
);
126 extern void cgroup_cancel_fork(struct task_struct
*p
);
127 extern void cgroup_post_fork(struct task_struct
*p
);
128 void cgroup_exit(struct task_struct
*p
);
129 void cgroup_release(struct task_struct
*p
);
130 void cgroup_free(struct task_struct
*p
);
132 int cgroup_init_early(void);
133 int cgroup_init(void);
135 int cgroup_parse_float(const char *input
, unsigned dec_shift
, s64
*v
);
138 * Iteration helpers and macros.
141 struct cgroup_subsys_state
*css_next_child(struct cgroup_subsys_state
*pos
,
142 struct cgroup_subsys_state
*parent
);
143 struct cgroup_subsys_state
*css_next_descendant_pre(struct cgroup_subsys_state
*pos
,
144 struct cgroup_subsys_state
*css
);
145 struct cgroup_subsys_state
*css_rightmost_descendant(struct cgroup_subsys_state
*pos
);
146 struct cgroup_subsys_state
*css_next_descendant_post(struct cgroup_subsys_state
*pos
,
147 struct cgroup_subsys_state
*css
);
149 struct task_struct
*cgroup_taskset_first(struct cgroup_taskset
*tset
,
150 struct cgroup_subsys_state
**dst_cssp
);
151 struct task_struct
*cgroup_taskset_next(struct cgroup_taskset
*tset
,
152 struct cgroup_subsys_state
**dst_cssp
);
154 void cgroup_enable_task_cg_lists(void);
155 void css_task_iter_start(struct cgroup_subsys_state
*css
, unsigned int flags
,
156 struct css_task_iter
*it
);
157 struct task_struct
*css_task_iter_next(struct css_task_iter
*it
);
158 void css_task_iter_end(struct css_task_iter
*it
);
161 * css_for_each_child - iterate through children of a css
162 * @pos: the css * to use as the loop cursor
163 * @parent: css whose children to walk
165 * Walk @parent's children. Must be called under rcu_read_lock().
167 * If a subsystem synchronizes ->css_online() and the start of iteration, a
168 * css which finished ->css_online() is guaranteed to be visible in the
169 * future iterations and will stay visible until the last reference is put.
170 * A css which hasn't finished ->css_online() or already finished
171 * ->css_offline() may show up during traversal. It's each subsystem's
172 * responsibility to synchronize against on/offlining.
174 * It is allowed to temporarily drop RCU read lock during iteration. The
175 * caller is responsible for ensuring that @pos remains accessible until
176 * the start of the next iteration by, for example, bumping the css refcnt.
178 #define css_for_each_child(pos, parent) \
179 for ((pos) = css_next_child(NULL, (parent)); (pos); \
180 (pos) = css_next_child((pos), (parent)))
183 * css_for_each_descendant_pre - pre-order walk of a css's descendants
184 * @pos: the css * to use as the loop cursor
185 * @root: css whose descendants to walk
187 * Walk @root's descendants. @root is included in the iteration and the
188 * first node to be visited. Must be called under rcu_read_lock().
190 * If a subsystem synchronizes ->css_online() and the start of iteration, a
191 * css which finished ->css_online() is guaranteed to be visible in the
192 * future iterations and will stay visible until the last reference is put.
193 * A css which hasn't finished ->css_online() or already finished
194 * ->css_offline() may show up during traversal. It's each subsystem's
195 * responsibility to synchronize against on/offlining.
197 * For example, the following guarantees that a descendant can't escape
198 * state updates of its ancestors.
202 * Lock @css's parent and @css;
203 * Inherit state from the parent;
207 * my_update_state(@css)
209 * css_for_each_descendant_pre(@pos, @css) {
212 * Update @css's state;
214 * Verify @pos is alive and inherit state from its parent;
219 * As long as the inheriting step, including checking the parent state, is
220 * enclosed inside @pos locking, double-locking the parent isn't necessary
221 * while inheriting. The state update to the parent is guaranteed to be
222 * visible by walking order and, as long as inheriting operations to the
223 * same @pos are atomic to each other, multiple updates racing each other
224 * still result in the correct state. It's guaranateed that at least one
225 * inheritance happens for any css after the latest update to its parent.
227 * If checking parent's state requires locking the parent, each inheriting
228 * iteration should lock and unlock both @pos->parent and @pos.
230 * Alternatively, a subsystem may choose to use a single global lock to
231 * synchronize ->css_online() and ->css_offline() against tree-walking
234 * It is allowed to temporarily drop RCU read lock during iteration. The
235 * caller is responsible for ensuring that @pos remains accessible until
236 * the start of the next iteration by, for example, bumping the css refcnt.
238 #define css_for_each_descendant_pre(pos, css) \
239 for ((pos) = css_next_descendant_pre(NULL, (css)); (pos); \
240 (pos) = css_next_descendant_pre((pos), (css)))
243 * css_for_each_descendant_post - post-order walk of a css's descendants
244 * @pos: the css * to use as the loop cursor
245 * @css: css whose descendants to walk
247 * Similar to css_for_each_descendant_pre() but performs post-order
248 * traversal instead. @root is included in the iteration and the last
249 * node to be visited.
251 * If a subsystem synchronizes ->css_online() and the start of iteration, a
252 * css which finished ->css_online() is guaranteed to be visible in the
253 * future iterations and will stay visible until the last reference is put.
254 * A css which hasn't finished ->css_online() or already finished
255 * ->css_offline() may show up during traversal. It's each subsystem's
256 * responsibility to synchronize against on/offlining.
258 * Note that the walk visibility guarantee example described in pre-order
259 * walk doesn't apply the same to post-order walks.
261 #define css_for_each_descendant_post(pos, css) \
262 for ((pos) = css_next_descendant_post(NULL, (css)); (pos); \
263 (pos) = css_next_descendant_post((pos), (css)))
266 * cgroup_taskset_for_each - iterate cgroup_taskset
267 * @task: the loop cursor
268 * @dst_css: the destination css
269 * @tset: taskset to iterate
271 * @tset may contain multiple tasks and they may belong to multiple
274 * On the v2 hierarchy, there may be tasks from multiple processes and they
275 * may not share the source or destination csses.
277 * On traditional hierarchies, when there are multiple tasks in @tset, if a
278 * task of a process is in @tset, all tasks of the process are in @tset.
279 * Also, all are guaranteed to share the same source and destination csses.
281 * Iteration is not in any specific order.
283 #define cgroup_taskset_for_each(task, dst_css, tset) \
284 for ((task) = cgroup_taskset_first((tset), &(dst_css)); \
286 (task) = cgroup_taskset_next((tset), &(dst_css)))
289 * cgroup_taskset_for_each_leader - iterate group leaders in a cgroup_taskset
290 * @leader: the loop cursor
291 * @dst_css: the destination css
292 * @tset: taskset to iterate
294 * Iterate threadgroup leaders of @tset. For single-task migrations, @tset
295 * may not contain any.
297 #define cgroup_taskset_for_each_leader(leader, dst_css, tset) \
298 for ((leader) = cgroup_taskset_first((tset), &(dst_css)); \
300 (leader) = cgroup_taskset_next((tset), &(dst_css))) \
301 if ((leader) != (leader)->group_leader) \
310 * css_get - obtain a reference on the specified css
313 * The caller must already have a reference.
315 static inline void css_get(struct cgroup_subsys_state
*css
)
317 if (!(css
->flags
& CSS_NO_REF
))
318 percpu_ref_get(&css
->refcnt
);
322 * css_get_many - obtain references on the specified css
324 * @n: number of references to get
326 * The caller must already have a reference.
328 static inline void css_get_many(struct cgroup_subsys_state
*css
, unsigned int n
)
330 if (!(css
->flags
& CSS_NO_REF
))
331 percpu_ref_get_many(&css
->refcnt
, n
);
335 * css_tryget - try to obtain a reference on the specified css
338 * Obtain a reference on @css unless it already has reached zero and is
339 * being released. This function doesn't care whether @css is on or
340 * offline. The caller naturally needs to ensure that @css is accessible
341 * but doesn't have to be holding a reference on it - IOW, RCU protected
342 * access is good enough for this function. Returns %true if a reference
343 * count was successfully obtained; %false otherwise.
345 static inline bool css_tryget(struct cgroup_subsys_state
*css
)
347 if (!(css
->flags
& CSS_NO_REF
))
348 return percpu_ref_tryget(&css
->refcnt
);
353 * css_tryget_online - try to obtain a reference on the specified css if online
356 * Obtain a reference on @css if it's online. The caller naturally needs
357 * to ensure that @css is accessible but doesn't have to be holding a
358 * reference on it - IOW, RCU protected access is good enough for this
359 * function. Returns %true if a reference count was successfully obtained;
362 static inline bool css_tryget_online(struct cgroup_subsys_state
*css
)
364 if (!(css
->flags
& CSS_NO_REF
))
365 return percpu_ref_tryget_live(&css
->refcnt
);
370 * css_is_dying - test whether the specified css is dying
373 * Test whether @css is in the process of offlining or already offline. In
374 * most cases, ->css_online() and ->css_offline() callbacks should be
375 * enough; however, the actual offline operations are RCU delayed and this
376 * test returns %true also when @css is scheduled to be offlined.
378 * This is useful, for example, when the use case requires synchronous
379 * behavior with respect to cgroup removal. cgroup removal schedules css
380 * offlining but the css can seem alive while the operation is being
381 * delayed. If the delay affects user visible semantics, this test can be
382 * used to resolve the situation.
384 static inline bool css_is_dying(struct cgroup_subsys_state
*css
)
386 return !(css
->flags
& CSS_NO_REF
) && percpu_ref_is_dying(&css
->refcnt
);
390 * css_put - put a css reference
393 * Put a reference obtained via css_get() and css_tryget_online().
395 static inline void css_put(struct cgroup_subsys_state
*css
)
397 if (!(css
->flags
& CSS_NO_REF
))
398 percpu_ref_put(&css
->refcnt
);
402 * css_put_many - put css references
404 * @n: number of references to put
406 * Put references obtained via css_get() and css_tryget_online().
408 static inline void css_put_many(struct cgroup_subsys_state
*css
, unsigned int n
)
410 if (!(css
->flags
& CSS_NO_REF
))
411 percpu_ref_put_many(&css
->refcnt
, n
);
414 static inline void cgroup_get(struct cgroup
*cgrp
)
416 css_get(&cgrp
->self
);
419 static inline bool cgroup_tryget(struct cgroup
*cgrp
)
421 return css_tryget(&cgrp
->self
);
424 static inline void cgroup_put(struct cgroup
*cgrp
)
426 css_put(&cgrp
->self
);
430 * task_css_set_check - obtain a task's css_set with extra access conditions
431 * @task: the task to obtain css_set for
432 * @__c: extra condition expression to be passed to rcu_dereference_check()
434 * A task's css_set is RCU protected, initialized and exited while holding
435 * task_lock(), and can only be modified while holding both cgroup_mutex
436 * and task_lock() while the task is alive. This macro verifies that the
437 * caller is inside proper critical section and returns @task's css_set.
439 * The caller can also specify additional allowed conditions via @__c, such
440 * as locks used during the cgroup_subsys::attach() methods.
442 #ifdef CONFIG_PROVE_RCU
443 extern struct mutex cgroup_mutex
;
444 extern spinlock_t css_set_lock
;
445 #define task_css_set_check(task, __c) \
446 rcu_dereference_check((task)->cgroups, \
447 lockdep_is_held(&cgroup_mutex) || \
448 lockdep_is_held(&css_set_lock) || \
449 ((task)->flags & PF_EXITING) || (__c))
451 #define task_css_set_check(task, __c) \
452 rcu_dereference((task)->cgroups)
456 * task_css_check - obtain css for (task, subsys) w/ extra access conds
457 * @task: the target task
458 * @subsys_id: the target subsystem ID
459 * @__c: extra condition expression to be passed to rcu_dereference_check()
461 * Return the cgroup_subsys_state for the (@task, @subsys_id) pair. The
462 * synchronization rules are the same as task_css_set_check().
464 #define task_css_check(task, subsys_id, __c) \
465 task_css_set_check((task), (__c))->subsys[(subsys_id)]
468 * task_css_set - obtain a task's css_set
469 * @task: the task to obtain css_set for
471 * See task_css_set_check().
473 static inline struct css_set
*task_css_set(struct task_struct
*task
)
475 return task_css_set_check(task
, false);
479 * task_css - obtain css for (task, subsys)
480 * @task: the target task
481 * @subsys_id: the target subsystem ID
483 * See task_css_check().
485 static inline struct cgroup_subsys_state
*task_css(struct task_struct
*task
,
488 return task_css_check(task
, subsys_id
, false);
492 * task_get_css - find and get the css for (task, subsys)
493 * @task: the target task
494 * @subsys_id: the target subsystem ID
496 * Find the css for the (@task, @subsys_id) combination, increment a
497 * reference on and return it. This function is guaranteed to return a
498 * valid css. The returned css may already have been offlined.
500 static inline struct cgroup_subsys_state
*
501 task_get_css(struct task_struct
*task
, int subsys_id
)
503 struct cgroup_subsys_state
*css
;
507 css
= task_css(task
, subsys_id
);
509 * Can't use css_tryget_online() here. A task which has
510 * PF_EXITING set may stay associated with an offline css.
511 * If such task calls this function, css_tryget_online()
514 if (likely(css_tryget(css
)))
523 * task_css_is_root - test whether a task belongs to the root css
524 * @task: the target task
525 * @subsys_id: the target subsystem ID
527 * Test whether @task belongs to the root css on the specified subsystem.
528 * May be invoked in any context.
530 static inline bool task_css_is_root(struct task_struct
*task
, int subsys_id
)
532 return task_css_check(task
, subsys_id
, true) ==
533 init_css_set
.subsys
[subsys_id
];
536 static inline struct cgroup
*task_cgroup(struct task_struct
*task
,
539 return task_css(task
, subsys_id
)->cgroup
;
542 static inline struct cgroup
*task_dfl_cgroup(struct task_struct
*task
)
544 return task_css_set(task
)->dfl_cgrp
;
547 static inline struct cgroup
*cgroup_parent(struct cgroup
*cgrp
)
549 struct cgroup_subsys_state
*parent_css
= cgrp
->self
.parent
;
552 return container_of(parent_css
, struct cgroup
, self
);
557 * cgroup_is_descendant - test ancestry
558 * @cgrp: the cgroup to be tested
559 * @ancestor: possible ancestor of @cgrp
561 * Test whether @cgrp is a descendant of @ancestor. It also returns %true
562 * if @cgrp == @ancestor. This function is safe to call as long as @cgrp
563 * and @ancestor are accessible.
565 static inline bool cgroup_is_descendant(struct cgroup
*cgrp
,
566 struct cgroup
*ancestor
)
568 if (cgrp
->root
!= ancestor
->root
|| cgrp
->level
< ancestor
->level
)
570 return cgrp
->ancestor_ids
[ancestor
->level
] == ancestor
->id
;
574 * cgroup_ancestor - find ancestor of cgroup
575 * @cgrp: cgroup to find ancestor of
576 * @ancestor_level: level of ancestor to find starting from root
578 * Find ancestor of cgroup at specified level starting from root if it exists
579 * and return pointer to it. Return NULL if @cgrp doesn't have ancestor at
582 * This function is safe to call as long as @cgrp is accessible.
584 static inline struct cgroup
*cgroup_ancestor(struct cgroup
*cgrp
,
587 if (cgrp
->level
< ancestor_level
)
589 while (cgrp
&& cgrp
->level
> ancestor_level
)
590 cgrp
= cgroup_parent(cgrp
);
595 * task_under_cgroup_hierarchy - test task's membership of cgroup ancestry
596 * @task: the task to be tested
597 * @ancestor: possible ancestor of @task's cgroup
599 * Tests whether @task's default cgroup hierarchy is a descendant of @ancestor.
600 * It follows all the same rules as cgroup_is_descendant, and only applies
601 * to the default hierarchy.
603 static inline bool task_under_cgroup_hierarchy(struct task_struct
*task
,
604 struct cgroup
*ancestor
)
606 struct css_set
*cset
= task_css_set(task
);
608 return cgroup_is_descendant(cset
->dfl_cgrp
, ancestor
);
611 /* no synchronization, the result can only be used as a hint */
612 static inline bool cgroup_is_populated(struct cgroup
*cgrp
)
614 return cgrp
->nr_populated_csets
+ cgrp
->nr_populated_domain_children
+
615 cgrp
->nr_populated_threaded_children
;
618 /* returns ino associated with a cgroup */
619 static inline ino_t
cgroup_ino(struct cgroup
*cgrp
)
621 return cgrp
->kn
->id
.ino
;
624 /* cft/css accessors for cftype->write() operation */
625 static inline struct cftype
*of_cft(struct kernfs_open_file
*of
)
630 struct cgroup_subsys_state
*of_css(struct kernfs_open_file
*of
);
632 /* cft/css accessors for cftype->seq_*() operations */
633 static inline struct cftype
*seq_cft(struct seq_file
*seq
)
635 return of_cft(seq
->private);
638 static inline struct cgroup_subsys_state
*seq_css(struct seq_file
*seq
)
640 return of_css(seq
->private);
644 * Name / path handling functions. All are thin wrappers around the kernfs
645 * counterparts and can be called under any context.
648 static inline int cgroup_name(struct cgroup
*cgrp
, char *buf
, size_t buflen
)
650 return kernfs_name(cgrp
->kn
, buf
, buflen
);
653 static inline int cgroup_path(struct cgroup
*cgrp
, char *buf
, size_t buflen
)
655 return kernfs_path(cgrp
->kn
, buf
, buflen
);
658 static inline void pr_cont_cgroup_name(struct cgroup
*cgrp
)
660 pr_cont_kernfs_name(cgrp
->kn
);
663 static inline void pr_cont_cgroup_path(struct cgroup
*cgrp
)
665 pr_cont_kernfs_path(cgrp
->kn
);
668 static inline struct psi_group
*cgroup_psi(struct cgroup
*cgrp
)
673 static inline void cgroup_init_kthreadd(void)
676 * kthreadd is inherited by all kthreads, keep it in the root so
677 * that the new kthreads are guaranteed to stay in the root until
678 * initialization is finished.
680 current
->no_cgroup_migration
= 1;
683 static inline void cgroup_kthread_ready(void)
686 * This kthread finished initialization. The creator should have
687 * set PF_NO_SETAFFINITY if this kthread should stay in the root.
689 current
->no_cgroup_migration
= 0;
692 static inline union kernfs_node_id
*cgroup_get_kernfs_id(struct cgroup
*cgrp
)
694 return &cgrp
->kn
->id
;
697 void cgroup_path_from_kernfs_id(const union kernfs_node_id
*id
,
698 char *buf
, size_t buflen
);
699 #else /* !CONFIG_CGROUPS */
701 struct cgroup_subsys_state
;
704 static inline void css_get(struct cgroup_subsys_state
*css
) {}
705 static inline void css_put(struct cgroup_subsys_state
*css
) {}
706 static inline int cgroup_attach_task_all(struct task_struct
*from
,
707 struct task_struct
*t
) { return 0; }
708 static inline int cgroupstats_build(struct cgroupstats
*stats
,
709 struct dentry
*dentry
) { return -EINVAL
; }
711 static inline void cgroup_fork(struct task_struct
*p
) {}
712 static inline int cgroup_can_fork(struct task_struct
*p
) { return 0; }
713 static inline void cgroup_cancel_fork(struct task_struct
*p
) {}
714 static inline void cgroup_post_fork(struct task_struct
*p
) {}
715 static inline void cgroup_exit(struct task_struct
*p
) {}
716 static inline void cgroup_release(struct task_struct
*p
) {}
717 static inline void cgroup_free(struct task_struct
*p
) {}
719 static inline int cgroup_init_early(void) { return 0; }
720 static inline int cgroup_init(void) { return 0; }
721 static inline void cgroup_init_kthreadd(void) {}
722 static inline void cgroup_kthread_ready(void) {}
723 static inline union kernfs_node_id
*cgroup_get_kernfs_id(struct cgroup
*cgrp
)
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(const union kernfs_node_id
*id
,
745 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
{
859 struct user_namespace
*user_ns
;
860 struct ucounts
*ucounts
;
861 struct css_set
*root_cset
;
864 extern struct cgroup_namespace init_cgroup_ns
;
866 #ifdef CONFIG_CGROUPS
868 void free_cgroup_ns(struct cgroup_namespace
*ns
);
870 struct cgroup_namespace
*copy_cgroup_ns(unsigned long flags
,
871 struct user_namespace
*user_ns
,
872 struct cgroup_namespace
*old_ns
);
874 int cgroup_path_ns(struct cgroup
*cgrp
, char *buf
, size_t buflen
,
875 struct cgroup_namespace
*ns
);
877 #else /* !CONFIG_CGROUPS */
879 static inline void free_cgroup_ns(struct cgroup_namespace
*ns
) { }
880 static inline struct cgroup_namespace
*
881 copy_cgroup_ns(unsigned long flags
, struct user_namespace
*user_ns
,
882 struct cgroup_namespace
*old_ns
)
887 #endif /* !CONFIG_CGROUPS */
889 static inline void get_cgroup_ns(struct cgroup_namespace
*ns
)
892 refcount_inc(&ns
->count
);
895 static inline void put_cgroup_ns(struct cgroup_namespace
*ns
)
897 if (ns
&& refcount_dec_and_test(&ns
->count
))
901 #ifdef CONFIG_CGROUPS
903 void cgroup_enter_frozen(void);
904 void cgroup_leave_frozen(bool always_leave
);
905 void cgroup_update_frozen(struct cgroup
*cgrp
);
906 void cgroup_freeze(struct cgroup
*cgrp
, bool freeze
);
907 void cgroup_freezer_migrate_task(struct task_struct
*task
, struct cgroup
*src
,
910 static inline bool cgroup_task_freeze(struct task_struct
*task
)
914 if (task
->flags
& PF_KTHREAD
)
918 ret
= test_bit(CGRP_FREEZE
, &task_dfl_cgroup(task
)->flags
);
924 static inline bool cgroup_task_frozen(struct task_struct
*task
)
929 #else /* !CONFIG_CGROUPS */
931 static inline void cgroup_enter_frozen(void) { }
932 static inline void cgroup_leave_frozen(bool always_leave
) { }
933 static inline bool cgroup_task_freeze(struct task_struct
*task
)
937 static inline bool cgroup_task_frozen(struct task_struct
*task
)
942 #endif /* !CONFIG_CGROUPS */
944 #ifdef CONFIG_CGROUP_BPF
945 static inline void cgroup_bpf_get(struct cgroup
*cgrp
)
947 percpu_ref_get(&cgrp
->bpf
.refcnt
);
950 static inline void cgroup_bpf_put(struct cgroup
*cgrp
)
952 percpu_ref_put(&cgrp
->bpf
.refcnt
);
955 #else /* CONFIG_CGROUP_BPF */
957 static inline void cgroup_bpf_get(struct cgroup
*cgrp
) {}
958 static inline void cgroup_bpf_put(struct cgroup
*cgrp
) {}
960 #endif /* CONFIG_CGROUP_BPF */
962 #endif /* _LINUX_CGROUP_H */