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)
46 /* a css_task_iter should be treated as an opaque object */
47 struct css_task_iter {
48 struct cgroup_subsys *ss;
51 struct list_head *cset_pos;
52 struct list_head *cset_head;
54 struct list_head *tcset_pos;
55 struct list_head *tcset_head;
57 struct list_head *task_pos;
58 struct list_head *tasks_head;
59 struct list_head *mg_tasks_head;
61 struct css_set *cur_cset;
62 struct css_set *cur_dcset;
63 struct task_struct *cur_task;
64 struct list_head iters_node; /* css_set->task_iters */
67 extern struct cgroup_root cgrp_dfl_root;
68 extern struct css_set init_css_set;
70 #define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys;
71 #include <linux/cgroup_subsys.h>
75 extern struct static_key_true _x ## _cgrp_subsys_enabled_key; \
76 extern struct static_key_true _x ## _cgrp_subsys_on_dfl_key;
77 #include <linux/cgroup_subsys.h>
81 * cgroup_subsys_enabled - fast test on whether a subsys is enabled
82 * @ss: subsystem in question
84 #define cgroup_subsys_enabled(ss) \
85 static_branch_likely(&ss ## _enabled_key)
88 * cgroup_subsys_on_dfl - fast test on whether a subsys is on default hierarchy
89 * @ss: subsystem in question
91 #define cgroup_subsys_on_dfl(ss) \
92 static_branch_likely(&ss ## _on_dfl_key)
94 bool css_has_online_children(struct cgroup_subsys_state *css);
95 struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss);
96 struct cgroup_subsys_state *cgroup_e_css(struct cgroup *cgroup,
97 struct cgroup_subsys *ss);
98 struct cgroup_subsys_state *cgroup_get_e_css(struct cgroup *cgroup,
99 struct cgroup_subsys *ss);
100 struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry,
101 struct cgroup_subsys *ss);
103 struct cgroup *cgroup_get_from_path(const char *path);
104 struct cgroup *cgroup_get_from_fd(int fd);
106 int cgroup_attach_task_all(struct task_struct *from, struct task_struct *);
107 int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from);
109 int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
110 int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
111 int cgroup_rm_cftypes(struct cftype *cfts);
112 void cgroup_file_notify(struct cgroup_file *cfile);
114 int task_cgroup_path(struct task_struct *task, char *buf, size_t buflen);
115 int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry);
116 int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns,
117 struct pid *pid, struct task_struct *tsk);
119 void cgroup_fork(struct task_struct *p);
120 extern int cgroup_can_fork(struct task_struct *p);
121 extern void cgroup_cancel_fork(struct task_struct *p);
122 extern void cgroup_post_fork(struct task_struct *p);
123 void cgroup_exit(struct task_struct *p);
124 void cgroup_free(struct task_struct *p);
126 int cgroup_init_early(void);
127 int cgroup_init(void);
130 * Iteration helpers and macros.
133 struct cgroup_subsys_state *css_next_child(struct cgroup_subsys_state *pos,
134 struct cgroup_subsys_state *parent);
135 struct cgroup_subsys_state *css_next_descendant_pre(struct cgroup_subsys_state *pos,
136 struct cgroup_subsys_state *css);
137 struct cgroup_subsys_state *css_rightmost_descendant(struct cgroup_subsys_state *pos);
138 struct cgroup_subsys_state *css_next_descendant_post(struct cgroup_subsys_state *pos,
139 struct cgroup_subsys_state *css);
141 struct task_struct *cgroup_taskset_first(struct cgroup_taskset *tset,
142 struct cgroup_subsys_state **dst_cssp);
143 struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset,
144 struct cgroup_subsys_state **dst_cssp);
146 void css_task_iter_start(struct cgroup_subsys_state *css, unsigned int flags,
147 struct css_task_iter *it);
148 struct task_struct *css_task_iter_next(struct css_task_iter *it);
149 void css_task_iter_end(struct css_task_iter *it);
152 * css_for_each_child - iterate through children of a css
153 * @pos: the css * to use as the loop cursor
154 * @parent: css whose children to walk
156 * Walk @parent's children. Must be called under rcu_read_lock().
158 * If a subsystem synchronizes ->css_online() and the start of iteration, a
159 * css which finished ->css_online() is guaranteed to be visible in the
160 * future iterations and will stay visible until the last reference is put.
161 * A css which hasn't finished ->css_online() or already finished
162 * ->css_offline() may show up during traversal. It's each subsystem's
163 * responsibility to synchronize against on/offlining.
165 * It is allowed to temporarily drop RCU read lock during iteration. The
166 * caller is responsible for ensuring that @pos remains accessible until
167 * the start of the next iteration by, for example, bumping the css refcnt.
169 #define css_for_each_child(pos, parent) \
170 for ((pos) = css_next_child(NULL, (parent)); (pos); \
171 (pos) = css_next_child((pos), (parent)))
174 * css_for_each_descendant_pre - pre-order walk of a css's descendants
175 * @pos: the css * to use as the loop cursor
176 * @root: css whose descendants to walk
178 * Walk @root's descendants. @root is included in the iteration and the
179 * first node to be visited. Must be called under rcu_read_lock().
181 * If a subsystem synchronizes ->css_online() and the start of iteration, a
182 * css which finished ->css_online() is guaranteed to be visible in the
183 * future iterations and will stay visible until the last reference is put.
184 * A css which hasn't finished ->css_online() or already finished
185 * ->css_offline() may show up during traversal. It's each subsystem's
186 * responsibility to synchronize against on/offlining.
188 * For example, the following guarantees that a descendant can't escape
189 * state updates of its ancestors.
193 * Lock @css's parent and @css;
194 * Inherit state from the parent;
198 * my_update_state(@css)
200 * css_for_each_descendant_pre(@pos, @css) {
203 * Update @css's state;
205 * Verify @pos is alive and inherit state from its parent;
210 * As long as the inheriting step, including checking the parent state, is
211 * enclosed inside @pos locking, double-locking the parent isn't necessary
212 * while inheriting. The state update to the parent is guaranteed to be
213 * visible by walking order and, as long as inheriting operations to the
214 * same @pos are atomic to each other, multiple updates racing each other
215 * still result in the correct state. It's guaranateed that at least one
216 * inheritance happens for any css after the latest update to its parent.
218 * If checking parent's state requires locking the parent, each inheriting
219 * iteration should lock and unlock both @pos->parent and @pos.
221 * Alternatively, a subsystem may choose to use a single global lock to
222 * synchronize ->css_online() and ->css_offline() against tree-walking
225 * It is allowed to temporarily drop RCU read lock during iteration. The
226 * caller is responsible for ensuring that @pos remains accessible until
227 * the start of the next iteration by, for example, bumping the css refcnt.
229 #define css_for_each_descendant_pre(pos, css) \
230 for ((pos) = css_next_descendant_pre(NULL, (css)); (pos); \
231 (pos) = css_next_descendant_pre((pos), (css)))
234 * css_for_each_descendant_post - post-order walk of a css's descendants
235 * @pos: the css * to use as the loop cursor
236 * @css: css whose descendants to walk
238 * Similar to css_for_each_descendant_pre() but performs post-order
239 * traversal instead. @root is included in the iteration and the last
240 * node to be visited.
242 * If a subsystem synchronizes ->css_online() and the start of iteration, a
243 * css which finished ->css_online() is guaranteed to be visible in the
244 * future iterations and will stay visible until the last reference is put.
245 * A css which hasn't finished ->css_online() or already finished
246 * ->css_offline() may show up during traversal. It's each subsystem's
247 * responsibility to synchronize against on/offlining.
249 * Note that the walk visibility guarantee example described in pre-order
250 * walk doesn't apply the same to post-order walks.
252 #define css_for_each_descendant_post(pos, css) \
253 for ((pos) = css_next_descendant_post(NULL, (css)); (pos); \
254 (pos) = css_next_descendant_post((pos), (css)))
257 * cgroup_taskset_for_each - iterate cgroup_taskset
258 * @task: the loop cursor
259 * @dst_css: the destination css
260 * @tset: taskset to iterate
262 * @tset may contain multiple tasks and they may belong to multiple
265 * On the v2 hierarchy, there may be tasks from multiple processes and they
266 * may not share the source or destination csses.
268 * On traditional hierarchies, when there are multiple tasks in @tset, if a
269 * task of a process is in @tset, all tasks of the process are in @tset.
270 * Also, all are guaranteed to share the same source and destination csses.
272 * Iteration is not in any specific order.
274 #define cgroup_taskset_for_each(task, dst_css, tset) \
275 for ((task) = cgroup_taskset_first((tset), &(dst_css)); \
277 (task) = cgroup_taskset_next((tset), &(dst_css)))
280 * cgroup_taskset_for_each_leader - iterate group leaders in a cgroup_taskset
281 * @leader: the loop cursor
282 * @dst_css: the destination css
283 * @tset: taskset to iterate
285 * Iterate threadgroup leaders of @tset. For single-task migrations, @tset
286 * may not contain any.
288 #define cgroup_taskset_for_each_leader(leader, dst_css, tset) \
289 for ((leader) = cgroup_taskset_first((tset), &(dst_css)); \
291 (leader) = cgroup_taskset_next((tset), &(dst_css))) \
292 if ((leader) != (leader)->group_leader) \
301 * css_get - obtain a reference on the specified css
304 * The caller must already have a reference.
306 static inline void css_get(struct cgroup_subsys_state *css)
308 if (!(css->flags & CSS_NO_REF))
309 percpu_ref_get(&css->refcnt);
313 * css_get_many - obtain references on the specified css
315 * @n: number of references to get
317 * The caller must already have a reference.
319 static inline void css_get_many(struct cgroup_subsys_state *css, unsigned int n)
321 if (!(css->flags & CSS_NO_REF))
322 percpu_ref_get_many(&css->refcnt, n);
326 * css_tryget - try to obtain a reference on the specified css
329 * Obtain a reference on @css unless it already has reached zero and is
330 * being released. This function doesn't care whether @css is on or
331 * offline. The caller naturally needs to ensure that @css is accessible
332 * but doesn't have to be holding a reference on it - IOW, RCU protected
333 * access is good enough for this function. Returns %true if a reference
334 * count was successfully obtained; %false otherwise.
336 static inline bool css_tryget(struct cgroup_subsys_state *css)
338 if (!(css->flags & CSS_NO_REF))
339 return percpu_ref_tryget(&css->refcnt);
344 * css_tryget_online - try to obtain a reference on the specified css if online
347 * Obtain a reference on @css if it's online. The caller naturally needs
348 * to ensure that @css is accessible but doesn't have to be holding a
349 * reference on it - IOW, RCU protected access is good enough for this
350 * function. Returns %true if a reference count was successfully obtained;
353 static inline bool css_tryget_online(struct cgroup_subsys_state *css)
355 if (!(css->flags & CSS_NO_REF))
356 return percpu_ref_tryget_live(&css->refcnt);
361 * css_is_dying - test whether the specified css is dying
364 * Test whether @css is in the process of offlining or already offline. In
365 * most cases, ->css_online() and ->css_offline() callbacks should be
366 * enough; however, the actual offline operations are RCU delayed and this
367 * test returns %true also when @css is scheduled to be offlined.
369 * This is useful, for example, when the use case requires synchronous
370 * behavior with respect to cgroup removal. cgroup removal schedules css
371 * offlining but the css can seem alive while the operation is being
372 * delayed. If the delay affects user visible semantics, this test can be
373 * used to resolve the situation.
375 static inline bool css_is_dying(struct cgroup_subsys_state *css)
377 return !(css->flags & CSS_NO_REF) && percpu_ref_is_dying(&css->refcnt);
381 * css_put - put a css reference
384 * Put a reference obtained via css_get() and css_tryget_online().
386 static inline void css_put(struct cgroup_subsys_state *css)
388 if (!(css->flags & CSS_NO_REF))
389 percpu_ref_put(&css->refcnt);
393 * css_put_many - put css references
395 * @n: number of references to put
397 * Put references obtained via css_get() and css_tryget_online().
399 static inline void css_put_many(struct cgroup_subsys_state *css, unsigned int n)
401 if (!(css->flags & CSS_NO_REF))
402 percpu_ref_put_many(&css->refcnt, n);
405 static inline void cgroup_get(struct cgroup *cgrp)
407 css_get(&cgrp->self);
410 static inline bool cgroup_tryget(struct cgroup *cgrp)
412 return css_tryget(&cgrp->self);
415 static inline void cgroup_put(struct cgroup *cgrp)
417 css_put(&cgrp->self);
421 * task_css_set_check - obtain a task's css_set with extra access conditions
422 * @task: the task to obtain css_set for
423 * @__c: extra condition expression to be passed to rcu_dereference_check()
425 * A task's css_set is RCU protected, initialized and exited while holding
426 * task_lock(), and can only be modified while holding both cgroup_mutex
427 * and task_lock() while the task is alive. This macro verifies that the
428 * caller is inside proper critical section and returns @task's css_set.
430 * The caller can also specify additional allowed conditions via @__c, such
431 * as locks used during the cgroup_subsys::attach() methods.
433 #ifdef CONFIG_PROVE_RCU
434 extern struct mutex cgroup_mutex;
435 extern spinlock_t css_set_lock;
436 #define task_css_set_check(task, __c) \
437 rcu_dereference_check((task)->cgroups, \
438 lockdep_is_held(&cgroup_mutex) || \
439 lockdep_is_held(&css_set_lock) || \
440 ((task)->flags & PF_EXITING) || (__c))
442 #define task_css_set_check(task, __c) \
443 rcu_dereference((task)->cgroups)
447 * task_css_check - obtain css for (task, subsys) w/ extra access conds
448 * @task: the target task
449 * @subsys_id: the target subsystem ID
450 * @__c: extra condition expression to be passed to rcu_dereference_check()
452 * Return the cgroup_subsys_state for the (@task, @subsys_id) pair. The
453 * synchronization rules are the same as task_css_set_check().
455 #define task_css_check(task, subsys_id, __c) \
456 task_css_set_check((task), (__c))->subsys[(subsys_id)]
459 * task_css_set - obtain a task's css_set
460 * @task: the task to obtain css_set for
462 * See task_css_set_check().
464 static inline struct css_set *task_css_set(struct task_struct *task)
466 return task_css_set_check(task, false);
470 * task_css - obtain css for (task, subsys)
471 * @task: the target task
472 * @subsys_id: the target subsystem ID
474 * See task_css_check().
476 static inline struct cgroup_subsys_state *task_css(struct task_struct *task,
479 return task_css_check(task, subsys_id, false);
483 * task_get_css - find and get the css for (task, subsys)
484 * @task: the target task
485 * @subsys_id: the target subsystem ID
487 * Find the css for the (@task, @subsys_id) combination, increment a
488 * reference on and return it. This function is guaranteed to return a
491 static inline struct cgroup_subsys_state *
492 task_get_css(struct task_struct *task, int subsys_id)
494 struct cgroup_subsys_state *css;
498 css = task_css(task, subsys_id);
499 if (likely(css_tryget_online(css)))
508 * task_css_is_root - test whether a task belongs to the root css
509 * @task: the target task
510 * @subsys_id: the target subsystem ID
512 * Test whether @task belongs to the root css on the specified subsystem.
513 * May be invoked in any context.
515 static inline bool task_css_is_root(struct task_struct *task, int subsys_id)
517 return task_css_check(task, subsys_id, true) ==
518 init_css_set.subsys[subsys_id];
521 static inline struct cgroup *task_cgroup(struct task_struct *task,
524 return task_css(task, subsys_id)->cgroup;
527 static inline struct cgroup *task_dfl_cgroup(struct task_struct *task)
529 return task_css_set(task)->dfl_cgrp;
532 static inline struct cgroup *cgroup_parent(struct cgroup *cgrp)
534 struct cgroup_subsys_state *parent_css = cgrp->self.parent;
537 return container_of(parent_css, struct cgroup, self);
542 * cgroup_is_descendant - test ancestry
543 * @cgrp: the cgroup to be tested
544 * @ancestor: possible ancestor of @cgrp
546 * Test whether @cgrp is a descendant of @ancestor. It also returns %true
547 * if @cgrp == @ancestor. This function is safe to call as long as @cgrp
548 * and @ancestor are accessible.
550 static inline bool cgroup_is_descendant(struct cgroup *cgrp,
551 struct cgroup *ancestor)
553 if (cgrp->root != ancestor->root || cgrp->level < ancestor->level)
555 return cgrp->ancestor_ids[ancestor->level] == ancestor->id;
559 * cgroup_ancestor - find ancestor of cgroup
560 * @cgrp: cgroup to find ancestor of
561 * @ancestor_level: level of ancestor to find starting from root
563 * Find ancestor of cgroup at specified level starting from root if it exists
564 * and return pointer to it. Return NULL if @cgrp doesn't have ancestor at
567 * This function is safe to call as long as @cgrp is accessible.
569 static inline struct cgroup *cgroup_ancestor(struct cgroup *cgrp,
574 if (cgrp->level < ancestor_level)
578 ptr && ptr->level > ancestor_level;
579 ptr = cgroup_parent(ptr))
582 if (ptr && ptr->level == ancestor_level)
589 * task_under_cgroup_hierarchy - test task's membership of cgroup ancestry
590 * @task: the task to be tested
591 * @ancestor: possible ancestor of @task's cgroup
593 * Tests whether @task's default cgroup hierarchy is a descendant of @ancestor.
594 * It follows all the same rules as cgroup_is_descendant, and only applies
595 * to the default hierarchy.
597 static inline bool task_under_cgroup_hierarchy(struct task_struct *task,
598 struct cgroup *ancestor)
600 struct css_set *cset = task_css_set(task);
602 return cgroup_is_descendant(cset->dfl_cgrp, ancestor);
605 /* no synchronization, the result can only be used as a hint */
606 static inline bool cgroup_is_populated(struct cgroup *cgrp)
608 return cgrp->nr_populated_csets + cgrp->nr_populated_domain_children +
609 cgrp->nr_populated_threaded_children;
612 /* returns ino associated with a cgroup */
613 static inline ino_t cgroup_ino(struct cgroup *cgrp)
615 return cgrp->kn->id.ino;
618 /* cft/css accessors for cftype->write() operation */
619 static inline struct cftype *of_cft(struct kernfs_open_file *of)
624 struct cgroup_subsys_state *of_css(struct kernfs_open_file *of);
626 /* cft/css accessors for cftype->seq_*() operations */
627 static inline struct cftype *seq_cft(struct seq_file *seq)
629 return of_cft(seq->private);
632 static inline struct cgroup_subsys_state *seq_css(struct seq_file *seq)
634 return of_css(seq->private);
638 * Name / path handling functions. All are thin wrappers around the kernfs
639 * counterparts and can be called under any context.
642 static inline int cgroup_name(struct cgroup *cgrp, char *buf, size_t buflen)
644 return kernfs_name(cgrp->kn, buf, buflen);
647 static inline int cgroup_path(struct cgroup *cgrp, char *buf, size_t buflen)
649 return kernfs_path(cgrp->kn, buf, buflen);
652 static inline void pr_cont_cgroup_name(struct cgroup *cgrp)
654 pr_cont_kernfs_name(cgrp->kn);
657 static inline void pr_cont_cgroup_path(struct cgroup *cgrp)
659 pr_cont_kernfs_path(cgrp->kn);
662 static inline void cgroup_init_kthreadd(void)
665 * kthreadd is inherited by all kthreads, keep it in the root so
666 * that the new kthreads are guaranteed to stay in the root until
667 * initialization is finished.
669 current->no_cgroup_migration = 1;
672 static inline void cgroup_kthread_ready(void)
675 * This kthread finished initialization. The creator should have
676 * set PF_NO_SETAFFINITY if this kthread should stay in the root.
678 current->no_cgroup_migration = 0;
681 static inline union kernfs_node_id *cgroup_get_kernfs_id(struct cgroup *cgrp)
683 return &cgrp->kn->id;
686 void cgroup_path_from_kernfs_id(const union kernfs_node_id *id,
687 char *buf, size_t buflen);
688 #else /* !CONFIG_CGROUPS */
690 struct cgroup_subsys_state;
693 static inline void css_put(struct cgroup_subsys_state *css) {}
694 static inline int cgroup_attach_task_all(struct task_struct *from,
695 struct task_struct *t) { return 0; }
696 static inline int cgroupstats_build(struct cgroupstats *stats,
697 struct dentry *dentry) { return -EINVAL; }
699 static inline void cgroup_fork(struct task_struct *p) {}
700 static inline int cgroup_can_fork(struct task_struct *p) { return 0; }
701 static inline void cgroup_cancel_fork(struct task_struct *p) {}
702 static inline void cgroup_post_fork(struct task_struct *p) {}
703 static inline void cgroup_exit(struct task_struct *p) {}
704 static inline void cgroup_free(struct task_struct *p) {}
706 static inline int cgroup_init_early(void) { return 0; }
707 static inline int cgroup_init(void) { return 0; }
708 static inline void cgroup_init_kthreadd(void) {}
709 static inline void cgroup_kthread_ready(void) {}
710 static inline union kernfs_node_id *cgroup_get_kernfs_id(struct cgroup *cgrp)
715 static inline bool task_under_cgroup_hierarchy(struct task_struct *task,
716 struct cgroup *ancestor)
721 static inline void cgroup_path_from_kernfs_id(const union kernfs_node_id *id,
722 char *buf, size_t buflen) {}
723 #endif /* !CONFIG_CGROUPS */
725 #ifdef CONFIG_CGROUPS
727 * cgroup scalable recursive statistics.
729 void cgroup_rstat_updated(struct cgroup *cgrp, int cpu);
730 void cgroup_rstat_flush(struct cgroup *cgrp);
731 void cgroup_rstat_flush_irqsafe(struct cgroup *cgrp);
732 void cgroup_rstat_flush_hold(struct cgroup *cgrp);
733 void cgroup_rstat_flush_release(void);
736 * Basic resource stats.
738 #ifdef CONFIG_CGROUP_CPUACCT
739 void cpuacct_charge(struct task_struct *tsk, u64 cputime);
740 void cpuacct_account_field(struct task_struct *tsk, int index, u64 val);
742 static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
743 static inline void cpuacct_account_field(struct task_struct *tsk, int index,
747 void __cgroup_account_cputime(struct cgroup *cgrp, u64 delta_exec);
748 void __cgroup_account_cputime_field(struct cgroup *cgrp,
749 enum cpu_usage_stat index, u64 delta_exec);
751 static inline void cgroup_account_cputime(struct task_struct *task,
756 cpuacct_charge(task, delta_exec);
759 cgrp = task_dfl_cgroup(task);
760 if (cgroup_parent(cgrp))
761 __cgroup_account_cputime(cgrp, delta_exec);
765 static inline void cgroup_account_cputime_field(struct task_struct *task,
766 enum cpu_usage_stat index,
771 cpuacct_account_field(task, index, delta_exec);
774 cgrp = task_dfl_cgroup(task);
775 if (cgroup_parent(cgrp))
776 __cgroup_account_cputime_field(cgrp, index, delta_exec);
780 #else /* CONFIG_CGROUPS */
782 static inline void cgroup_account_cputime(struct task_struct *task,
784 static inline void cgroup_account_cputime_field(struct task_struct *task,
785 enum cpu_usage_stat index,
788 #endif /* CONFIG_CGROUPS */
791 * sock->sk_cgrp_data handling. For more info, see sock_cgroup_data
792 * definition in cgroup-defs.h.
794 #ifdef CONFIG_SOCK_CGROUP_DATA
796 #if defined(CONFIG_CGROUP_NET_PRIO) || defined(CONFIG_CGROUP_NET_CLASSID)
797 extern spinlock_t cgroup_sk_update_lock;
800 void cgroup_sk_alloc_disable(void);
801 void cgroup_sk_alloc(struct sock_cgroup_data *skcd);
802 void cgroup_sk_free(struct sock_cgroup_data *skcd);
804 static inline struct cgroup *sock_cgroup_ptr(struct sock_cgroup_data *skcd)
806 #if defined(CONFIG_CGROUP_NET_PRIO) || defined(CONFIG_CGROUP_NET_CLASSID)
810 * @skcd->val is 64bit but the following is safe on 32bit too as we
811 * just need the lower ulong to be written and read atomically.
813 v = READ_ONCE(skcd->val);
816 return &cgrp_dfl_root.cgrp;
818 return (struct cgroup *)(unsigned long)v ?: &cgrp_dfl_root.cgrp;
820 return (struct cgroup *)(unsigned long)skcd->val;
824 #else /* CONFIG_CGROUP_DATA */
826 static inline void cgroup_sk_alloc(struct sock_cgroup_data *skcd) {}
827 static inline void cgroup_sk_free(struct sock_cgroup_data *skcd) {}
829 #endif /* CONFIG_CGROUP_DATA */
831 struct cgroup_namespace {
834 struct user_namespace *user_ns;
835 struct ucounts *ucounts;
836 struct css_set *root_cset;
839 extern struct cgroup_namespace init_cgroup_ns;
841 #ifdef CONFIG_CGROUPS
843 void free_cgroup_ns(struct cgroup_namespace *ns);
845 struct cgroup_namespace *copy_cgroup_ns(unsigned long flags,
846 struct user_namespace *user_ns,
847 struct cgroup_namespace *old_ns);
849 int cgroup_path_ns(struct cgroup *cgrp, char *buf, size_t buflen,
850 struct cgroup_namespace *ns);
852 #else /* !CONFIG_CGROUPS */
854 static inline void free_cgroup_ns(struct cgroup_namespace *ns) { }
855 static inline struct cgroup_namespace *
856 copy_cgroup_ns(unsigned long flags, struct user_namespace *user_ns,
857 struct cgroup_namespace *old_ns)
862 #endif /* !CONFIG_CGROUPS */
864 static inline void get_cgroup_ns(struct cgroup_namespace *ns)
867 refcount_inc(&ns->count);
870 static inline void put_cgroup_ns(struct cgroup_namespace *ns)
872 if (ns && refcount_dec_and_test(&ns->count))
876 #endif /* _LINUX_CGROUP_H */