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/cpumask.h> 14#include <linux/nodemask.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/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> 27 28#include <linux/cgroup-defs.h> 29 30struct kernel_clone_args; 31 32#ifdef CONFIG_CGROUPS 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 43enum { 44 CSS_TASK_ITER_PROCS = (1U << 0), /* walk only threadgroup leaders */ 45 CSS_TASK_ITER_THREADED = (1U << 1), /* walk all threaded css_sets in the domain */ 46 CSS_TASK_ITER_SKIPPED = (1U << 16), /* internal flags */ 47}; 48 49/* a css_task_iter should be treated as an opaque object */ 50struct css_task_iter { 51 struct cgroup_subsys *ss; 52 unsigned int flags; 53 54 struct list_head *cset_pos; 55 struct list_head *cset_head; 56 57 struct list_head *tcset_pos; 58 struct list_head *tcset_head; 59 60 struct list_head *task_pos; 61 62 struct list_head *cur_tasks_head; 63 struct css_set *cur_cset; 64 struct css_set *cur_dcset; 65 struct task_struct *cur_task; 66 struct list_head iters_node; /* css_set->task_iters */ 67}; 68 69extern struct file_system_type cgroup_fs_type; 70extern struct cgroup_root cgrp_dfl_root; 71extern struct css_set init_css_set; 72extern spinlock_t css_set_lock; 73 74#define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys; 75#include <linux/cgroup_subsys.h> 76#undef SUBSYS 77 78#define SUBSYS(_x) \ 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> 82#undef SUBSYS 83 84/** 85 * cgroup_subsys_enabled - fast test on whether a subsys is enabled 86 * @ss: subsystem in question 87 */ 88#define cgroup_subsys_enabled(ss) \ 89 static_branch_likely(&ss ## _enabled_key) 90 91/** 92 * cgroup_subsys_on_dfl - fast test on whether a subsys is on default hierarchy 93 * @ss: subsystem in question 94 */ 95#define cgroup_subsys_on_dfl(ss) \ 96 static_branch_likely(&ss ## _on_dfl_key) 97 98bool css_has_online_children(struct cgroup_subsys_state *css); 99struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss); 100struct cgroup_subsys_state *cgroup_e_css(struct cgroup *cgroup, 101 struct cgroup_subsys *ss); 102struct cgroup_subsys_state *cgroup_get_e_css(struct cgroup *cgroup, 103 struct cgroup_subsys *ss); 104struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry, 105 struct cgroup_subsys *ss); 106 107struct cgroup *cgroup_get_from_path(const char *path); 108struct cgroup *cgroup_get_from_fd(int fd); 109struct cgroup *cgroup_v1v2_get_from_fd(int fd); 110 111int cgroup_attach_task_all(struct task_struct *from, struct task_struct *); 112int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from); 113 114int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts); 115int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts); 116int cgroup_rm_cftypes(struct cftype *cfts); 117void cgroup_file_notify(struct cgroup_file *cfile); 118void cgroup_file_show(struct cgroup_file *cfile, bool show); 119 120int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry); 121int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns, 122 struct pid *pid, struct task_struct *tsk); 123 124void cgroup_fork(struct task_struct *p); 125extern int cgroup_can_fork(struct task_struct *p, 126 struct kernel_clone_args *kargs); 127extern void cgroup_cancel_fork(struct task_struct *p, 128 struct kernel_clone_args *kargs); 129extern void cgroup_post_fork(struct task_struct *p, 130 struct kernel_clone_args *kargs); 131void cgroup_exit(struct task_struct *p); 132void cgroup_release(struct task_struct *p); 133void cgroup_free(struct task_struct *p); 134 135int cgroup_init_early(void); 136int cgroup_init(void); 137 138int cgroup_parse_float(const char *input, unsigned dec_shift, s64 *v); 139 140/* 141 * Iteration helpers and macros. 142 */ 143 144struct cgroup_subsys_state *css_next_child(struct cgroup_subsys_state *pos, 145 struct cgroup_subsys_state *parent); 146struct cgroup_subsys_state *css_next_descendant_pre(struct cgroup_subsys_state *pos, 147 struct cgroup_subsys_state *css); 148struct cgroup_subsys_state *css_rightmost_descendant(struct cgroup_subsys_state *pos); 149struct cgroup_subsys_state *css_next_descendant_post(struct cgroup_subsys_state *pos, 150 struct cgroup_subsys_state *css); 151 152struct task_struct *cgroup_taskset_first(struct cgroup_taskset *tset, 153 struct cgroup_subsys_state **dst_cssp); 154struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset, 155 struct cgroup_subsys_state **dst_cssp); 156 157void css_task_iter_start(struct cgroup_subsys_state *css, unsigned int flags, 158 struct css_task_iter *it); 159struct task_struct *css_task_iter_next(struct css_task_iter *it); 160void css_task_iter_end(struct css_task_iter *it); 161 162/** 163 * css_for_each_child - iterate through children of a css 164 * @pos: the css * to use as the loop cursor 165 * @parent: css whose children to walk 166 * 167 * Walk @parent's children. Must be called under rcu_read_lock(). 168 * 169 * If a subsystem synchronizes ->css_online() and the start of iteration, a 170 * css which finished ->css_online() is guaranteed to be visible in the 171 * future iterations and will stay visible until the last reference is put. 172 * A css which hasn't finished ->css_online() or already finished 173 * ->css_offline() may show up during traversal. It's each subsystem's 174 * responsibility to synchronize against on/offlining. 175 * 176 * It is allowed to temporarily drop RCU read lock during iteration. The 177 * caller is responsible for ensuring that @pos remains accessible until 178 * the start of the next iteration by, for example, bumping the css refcnt. 179 */ 180#define css_for_each_child(pos, parent) \ 181 for ((pos) = css_next_child(NULL, (parent)); (pos); \ 182 (pos) = css_next_child((pos), (parent))) 183 184/** 185 * css_for_each_descendant_pre - pre-order walk of a css's descendants 186 * @pos: the css * to use as the loop cursor 187 * @root: css whose descendants to walk 188 * 189 * Walk @root's descendants. @root is included in the iteration and the 190 * first node to be visited. Must be called under rcu_read_lock(). 191 * 192 * If a subsystem synchronizes ->css_online() and the start of iteration, a 193 * css which finished ->css_online() is guaranteed to be visible in the 194 * future iterations and will stay visible until the last reference is put. 195 * A css which hasn't finished ->css_online() or already finished 196 * ->css_offline() may show up during traversal. It's each subsystem's 197 * responsibility to synchronize against on/offlining. 198 * 199 * For example, the following guarantees that a descendant can't escape 200 * state updates of its ancestors. 201 * 202 * my_online(@css) 203 * { 204 * Lock @css's parent and @css; 205 * Inherit state from the parent; 206 * Unlock both. 207 * } 208 * 209 * my_update_state(@css) 210 * { 211 * css_for_each_descendant_pre(@pos, @css) { 212 * Lock @pos; 213 * if (@pos == @css) 214 * Update @css's state; 215 * else 216 * Verify @pos is alive and inherit state from its parent; 217 * Unlock @pos; 218 * } 219 * } 220 * 221 * As long as the inheriting step, including checking the parent state, is 222 * enclosed inside @pos locking, double-locking the parent isn't necessary 223 * while inheriting. The state update to the parent is guaranteed to be 224 * visible by walking order and, as long as inheriting operations to the 225 * same @pos are atomic to each other, multiple updates racing each other 226 * still result in the correct state. It's guaranateed that at least one 227 * inheritance happens for any css after the latest update to its parent. 228 * 229 * If checking parent's state requires locking the parent, each inheriting 230 * iteration should lock and unlock both @pos->parent and @pos. 231 * 232 * Alternatively, a subsystem may choose to use a single global lock to 233 * synchronize ->css_online() and ->css_offline() against tree-walking 234 * operations. 235 * 236 * It is allowed to temporarily drop RCU read lock during iteration. The 237 * caller is responsible for ensuring that @pos remains accessible until 238 * the start of the next iteration by, for example, bumping the css refcnt. 239 */ 240#define css_for_each_descendant_pre(pos, css) \ 241 for ((pos) = css_next_descendant_pre(NULL, (css)); (pos); \ 242 (pos) = css_next_descendant_pre((pos), (css))) 243 244/** 245 * css_for_each_descendant_post - post-order walk of a css's descendants 246 * @pos: the css * to use as the loop cursor 247 * @css: css whose descendants to walk 248 * 249 * Similar to css_for_each_descendant_pre() but performs post-order 250 * traversal instead. @root is included in the iteration and the last 251 * node to be visited. 252 * 253 * If a subsystem synchronizes ->css_online() and the start of iteration, a 254 * css which finished ->css_online() is guaranteed to be visible in the 255 * future iterations and will stay visible until the last reference is put. 256 * A css which hasn't finished ->css_online() or already finished 257 * ->css_offline() may show up during traversal. It's each subsystem's 258 * responsibility to synchronize against on/offlining. 259 * 260 * Note that the walk visibility guarantee example described in pre-order 261 * walk doesn't apply the same to post-order walks. 262 */ 263#define css_for_each_descendant_post(pos, css) \ 264 for ((pos) = css_next_descendant_post(NULL, (css)); (pos); \ 265 (pos) = css_next_descendant_post((pos), (css))) 266 267/** 268 * cgroup_taskset_for_each - iterate cgroup_taskset 269 * @task: the loop cursor 270 * @dst_css: the destination css 271 * @tset: taskset to iterate 272 * 273 * @tset may contain multiple tasks and they may belong to multiple 274 * processes. 275 * 276 * On the v2 hierarchy, there may be tasks from multiple processes and they 277 * may not share the source or destination csses. 278 * 279 * On traditional hierarchies, when there are multiple tasks in @tset, if a 280 * task of a process is in @tset, all tasks of the process are in @tset. 281 * Also, all are guaranteed to share the same source and destination csses. 282 * 283 * Iteration is not in any specific order. 284 */ 285#define cgroup_taskset_for_each(task, dst_css, tset) \ 286 for ((task) = cgroup_taskset_first((tset), &(dst_css)); \ 287 (task); \ 288 (task) = cgroup_taskset_next((tset), &(dst_css))) 289 290/** 291 * cgroup_taskset_for_each_leader - iterate group leaders in a cgroup_taskset 292 * @leader: the loop cursor 293 * @dst_css: the destination css 294 * @tset: taskset to iterate 295 * 296 * Iterate threadgroup leaders of @tset. For single-task migrations, @tset 297 * may not contain any. 298 */ 299#define cgroup_taskset_for_each_leader(leader, dst_css, tset) \ 300 for ((leader) = cgroup_taskset_first((tset), &(dst_css)); \ 301 (leader); \ 302 (leader) = cgroup_taskset_next((tset), &(dst_css))) \ 303 if ((leader) != (leader)->group_leader) \ 304 ; \ 305 else 306 307/* 308 * Inline functions. 309 */ 310 311#ifdef CONFIG_DEBUG_CGROUP_REF 312void css_get(struct cgroup_subsys_state *css); 313void css_get_many(struct cgroup_subsys_state *css, unsigned int n); 314bool css_tryget(struct cgroup_subsys_state *css); 315bool css_tryget_online(struct cgroup_subsys_state *css); 316void css_put(struct cgroup_subsys_state *css); 317void css_put_many(struct cgroup_subsys_state *css, unsigned int n); 318#else 319#define CGROUP_REF_FN_ATTRS static inline 320#define CGROUP_REF_EXPORT(fn) 321#include <linux/cgroup_refcnt.h> 322#endif 323 324static inline u64 cgroup_id(const struct cgroup *cgrp) 325{ 326 return cgrp->kn->id; 327} 328 329/** 330 * css_is_dying - test whether the specified css is dying 331 * @css: target css 332 * 333 * Test whether @css is in the process of offlining or already offline. In 334 * most cases, ->css_online() and ->css_offline() callbacks should be 335 * enough; however, the actual offline operations are RCU delayed and this 336 * test returns %true also when @css is scheduled to be offlined. 337 * 338 * This is useful, for example, when the use case requires synchronous 339 * behavior with respect to cgroup removal. cgroup removal schedules css 340 * offlining but the css can seem alive while the operation is being 341 * delayed. If the delay affects user visible semantics, this test can be 342 * used to resolve the situation. 343 */ 344static inline bool css_is_dying(struct cgroup_subsys_state *css) 345{ 346 return !(css->flags & CSS_NO_REF) && percpu_ref_is_dying(&css->refcnt); 347} 348 349static inline void cgroup_get(struct cgroup *cgrp) 350{ 351 css_get(&cgrp->self); 352} 353 354static inline bool cgroup_tryget(struct cgroup *cgrp) 355{ 356 return css_tryget(&cgrp->self); 357} 358 359static inline void cgroup_put(struct cgroup *cgrp) 360{ 361 css_put(&cgrp->self); 362} 363 364extern struct mutex cgroup_mutex; 365 366static inline void cgroup_lock(void) 367{ 368 mutex_lock(&cgroup_mutex); 369} 370 371static inline void cgroup_unlock(void) 372{ 373 mutex_unlock(&cgroup_mutex); 374} 375 376/** 377 * task_css_set_check - obtain a task's css_set with extra access conditions 378 * @task: the task to obtain css_set for 379 * @__c: extra condition expression to be passed to rcu_dereference_check() 380 * 381 * A task's css_set is RCU protected, initialized and exited while holding 382 * task_lock(), and can only be modified while holding both cgroup_mutex 383 * and task_lock() while the task is alive. This macro verifies that the 384 * caller is inside proper critical section and returns @task's css_set. 385 * 386 * The caller can also specify additional allowed conditions via @__c, such 387 * as locks used during the cgroup_subsys::attach() methods. 388 */ 389#ifdef CONFIG_PROVE_RCU 390#define task_css_set_check(task, __c) \ 391 rcu_dereference_check((task)->cgroups, \ 392 rcu_read_lock_sched_held() || \ 393 lockdep_is_held(&cgroup_mutex) || \ 394 lockdep_is_held(&css_set_lock) || \ 395 ((task)->flags & PF_EXITING) || (__c)) 396#else 397#define task_css_set_check(task, __c) \ 398 rcu_dereference((task)->cgroups) 399#endif 400 401/** 402 * task_css_check - obtain css for (task, subsys) w/ extra access conds 403 * @task: the target task 404 * @subsys_id: the target subsystem ID 405 * @__c: extra condition expression to be passed to rcu_dereference_check() 406 * 407 * Return the cgroup_subsys_state for the (@task, @subsys_id) pair. The 408 * synchronization rules are the same as task_css_set_check(). 409 */ 410#define task_css_check(task, subsys_id, __c) \ 411 task_css_set_check((task), (__c))->subsys[(subsys_id)] 412 413/** 414 * task_css_set - obtain a task's css_set 415 * @task: the task to obtain css_set for 416 * 417 * See task_css_set_check(). 418 */ 419static inline struct css_set *task_css_set(struct task_struct *task) 420{ 421 return task_css_set_check(task, false); 422} 423 424/** 425 * task_css - obtain css for (task, subsys) 426 * @task: the target task 427 * @subsys_id: the target subsystem ID 428 * 429 * See task_css_check(). 430 */ 431static inline struct cgroup_subsys_state *task_css(struct task_struct *task, 432 int subsys_id) 433{ 434 return task_css_check(task, subsys_id, false); 435} 436 437/** 438 * task_get_css - find and get the css for (task, subsys) 439 * @task: the target task 440 * @subsys_id: the target subsystem ID 441 * 442 * Find the css for the (@task, @subsys_id) combination, increment a 443 * reference on and return it. This function is guaranteed to return a 444 * valid css. The returned css may already have been offlined. 445 */ 446static inline struct cgroup_subsys_state * 447task_get_css(struct task_struct *task, int subsys_id) 448{ 449 struct cgroup_subsys_state *css; 450 451 rcu_read_lock(); 452 while (true) { 453 css = task_css(task, subsys_id); 454 /* 455 * Can't use css_tryget_online() here. A task which has 456 * PF_EXITING set may stay associated with an offline css. 457 * If such task calls this function, css_tryget_online() 458 * will keep failing. 459 */ 460 if (likely(css_tryget(css))) 461 break; 462 cpu_relax(); 463 } 464 rcu_read_unlock(); 465 return css; 466} 467 468/** 469 * task_css_is_root - test whether a task belongs to the root css 470 * @task: the target task 471 * @subsys_id: the target subsystem ID 472 * 473 * Test whether @task belongs to the root css on the specified subsystem. 474 * May be invoked in any context. 475 */ 476static inline bool task_css_is_root(struct task_struct *task, int subsys_id) 477{ 478 return task_css_check(task, subsys_id, true) == 479 init_css_set.subsys[subsys_id]; 480} 481 482static inline struct cgroup *task_cgroup(struct task_struct *task, 483 int subsys_id) 484{ 485 return task_css(task, subsys_id)->cgroup; 486} 487 488static inline struct cgroup *task_dfl_cgroup(struct task_struct *task) 489{ 490 return task_css_set(task)->dfl_cgrp; 491} 492 493static inline struct cgroup *cgroup_parent(struct cgroup *cgrp) 494{ 495 struct cgroup_subsys_state *parent_css = cgrp->self.parent; 496 497 if (parent_css) 498 return container_of(parent_css, struct cgroup, self); 499 return NULL; 500} 501 502/** 503 * cgroup_is_descendant - test ancestry 504 * @cgrp: the cgroup to be tested 505 * @ancestor: possible ancestor of @cgrp 506 * 507 * Test whether @cgrp is a descendant of @ancestor. It also returns %true 508 * if @cgrp == @ancestor. This function is safe to call as long as @cgrp 509 * and @ancestor are accessible. 510 */ 511static inline bool cgroup_is_descendant(struct cgroup *cgrp, 512 struct cgroup *ancestor) 513{ 514 if (cgrp->root != ancestor->root || cgrp->level < ancestor->level) 515 return false; 516 return cgrp->ancestors[ancestor->level] == ancestor; 517} 518 519/** 520 * cgroup_ancestor - find ancestor of cgroup 521 * @cgrp: cgroup to find ancestor of 522 * @ancestor_level: level of ancestor to find starting from root 523 * 524 * Find ancestor of cgroup at specified level starting from root if it exists 525 * and return pointer to it. Return NULL if @cgrp doesn't have ancestor at 526 * @ancestor_level. 527 * 528 * This function is safe to call as long as @cgrp is accessible. 529 */ 530static inline struct cgroup *cgroup_ancestor(struct cgroup *cgrp, 531 int ancestor_level) 532{ 533 if (ancestor_level < 0 || ancestor_level > cgrp->level) 534 return NULL; 535 return cgrp->ancestors[ancestor_level]; 536} 537 538/** 539 * task_under_cgroup_hierarchy - test task's membership of cgroup ancestry 540 * @task: the task to be tested 541 * @ancestor: possible ancestor of @task's cgroup 542 * 543 * Tests whether @task's default cgroup hierarchy is a descendant of @ancestor. 544 * It follows all the same rules as cgroup_is_descendant, and only applies 545 * to the default hierarchy. 546 */ 547static inline bool task_under_cgroup_hierarchy(struct task_struct *task, 548 struct cgroup *ancestor) 549{ 550 struct css_set *cset = task_css_set(task); 551 552 return cgroup_is_descendant(cset->dfl_cgrp, ancestor); 553} 554 555/* no synchronization, the result can only be used as a hint */ 556static inline bool cgroup_is_populated(struct cgroup *cgrp) 557{ 558 return cgrp->nr_populated_csets + cgrp->nr_populated_domain_children + 559 cgrp->nr_populated_threaded_children; 560} 561 562/* returns ino associated with a cgroup */ 563static inline ino_t cgroup_ino(struct cgroup *cgrp) 564{ 565 return kernfs_ino(cgrp->kn); 566} 567 568/* cft/css accessors for cftype->write() operation */ 569static inline struct cftype *of_cft(struct kernfs_open_file *of) 570{ 571 return of->kn->priv; 572} 573 574struct cgroup_subsys_state *of_css(struct kernfs_open_file *of); 575 576/* cft/css accessors for cftype->seq_*() operations */ 577static inline struct cftype *seq_cft(struct seq_file *seq) 578{ 579 return of_cft(seq->private); 580} 581 582static inline struct cgroup_subsys_state *seq_css(struct seq_file *seq) 583{ 584 return of_css(seq->private); 585} 586 587/* 588 * Name / path handling functions. All are thin wrappers around the kernfs 589 * counterparts and can be called under any context. 590 */ 591 592static inline int cgroup_name(struct cgroup *cgrp, char *buf, size_t buflen) 593{ 594 return kernfs_name(cgrp->kn, buf, buflen); 595} 596 597static inline int cgroup_path(struct cgroup *cgrp, char *buf, size_t buflen) 598{ 599 return kernfs_path(cgrp->kn, buf, buflen); 600} 601 602static inline void pr_cont_cgroup_name(struct cgroup *cgrp) 603{ 604 pr_cont_kernfs_name(cgrp->kn); 605} 606 607static inline void pr_cont_cgroup_path(struct cgroup *cgrp) 608{ 609 pr_cont_kernfs_path(cgrp->kn); 610} 611 612bool cgroup_psi_enabled(void); 613 614static inline void cgroup_init_kthreadd(void) 615{ 616 /* 617 * kthreadd is inherited by all kthreads, keep it in the root so 618 * that the new kthreads are guaranteed to stay in the root until 619 * initialization is finished. 620 */ 621 current->no_cgroup_migration = 1; 622} 623 624static inline void cgroup_kthread_ready(void) 625{ 626 /* 627 * This kthread finished initialization. The creator should have 628 * set PF_NO_SETAFFINITY if this kthread should stay in the root. 629 */ 630 current->no_cgroup_migration = 0; 631} 632 633void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen); 634struct cgroup *cgroup_get_from_id(u64 id); 635#else /* !CONFIG_CGROUPS */ 636 637struct cgroup_subsys_state; 638struct cgroup; 639 640static inline u64 cgroup_id(const struct cgroup *cgrp) { return 1; } 641static inline void css_get(struct cgroup_subsys_state *css) {} 642static inline void css_put(struct cgroup_subsys_state *css) {} 643static inline void cgroup_lock(void) {} 644static inline void cgroup_unlock(void) {} 645static inline int cgroup_attach_task_all(struct task_struct *from, 646 struct task_struct *t) { return 0; } 647static inline int cgroupstats_build(struct cgroupstats *stats, 648 struct dentry *dentry) { return -EINVAL; } 649 650static inline void cgroup_fork(struct task_struct *p) {} 651static inline int cgroup_can_fork(struct task_struct *p, 652 struct kernel_clone_args *kargs) { return 0; } 653static inline void cgroup_cancel_fork(struct task_struct *p, 654 struct kernel_clone_args *kargs) {} 655static inline void cgroup_post_fork(struct task_struct *p, 656 struct kernel_clone_args *kargs) {} 657static inline void cgroup_exit(struct task_struct *p) {} 658static inline void cgroup_release(struct task_struct *p) {} 659static inline void cgroup_free(struct task_struct *p) {} 660 661static inline int cgroup_init_early(void) { return 0; } 662static inline int cgroup_init(void) { return 0; } 663static inline void cgroup_init_kthreadd(void) {} 664static inline void cgroup_kthread_ready(void) {} 665 666static inline struct cgroup *cgroup_parent(struct cgroup *cgrp) 667{ 668 return NULL; 669} 670 671static inline bool cgroup_psi_enabled(void) 672{ 673 return false; 674} 675 676static inline bool task_under_cgroup_hierarchy(struct task_struct *task, 677 struct cgroup *ancestor) 678{ 679 return true; 680} 681 682static inline void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen) 683{} 684#endif /* !CONFIG_CGROUPS */ 685 686#ifdef CONFIG_CGROUPS 687/* 688 * cgroup scalable recursive statistics. 689 */ 690void cgroup_rstat_updated(struct cgroup *cgrp, int cpu); 691void cgroup_rstat_flush(struct cgroup *cgrp); 692void cgroup_rstat_flush_hold(struct cgroup *cgrp); 693void cgroup_rstat_flush_release(void); 694 695/* 696 * Basic resource stats. 697 */ 698#ifdef CONFIG_CGROUP_CPUACCT 699void cpuacct_charge(struct task_struct *tsk, u64 cputime); 700void cpuacct_account_field(struct task_struct *tsk, int index, u64 val); 701#else 702static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {} 703static inline void cpuacct_account_field(struct task_struct *tsk, int index, 704 u64 val) {} 705#endif 706 707void __cgroup_account_cputime(struct cgroup *cgrp, u64 delta_exec); 708void __cgroup_account_cputime_field(struct cgroup *cgrp, 709 enum cpu_usage_stat index, u64 delta_exec); 710 711static inline void cgroup_account_cputime(struct task_struct *task, 712 u64 delta_exec) 713{ 714 struct cgroup *cgrp; 715 716 cpuacct_charge(task, delta_exec); 717 718 cgrp = task_dfl_cgroup(task); 719 if (cgroup_parent(cgrp)) 720 __cgroup_account_cputime(cgrp, delta_exec); 721} 722 723static inline void cgroup_account_cputime_field(struct task_struct *task, 724 enum cpu_usage_stat index, 725 u64 delta_exec) 726{ 727 struct cgroup *cgrp; 728 729 cpuacct_account_field(task, index, delta_exec); 730 731 cgrp = task_dfl_cgroup(task); 732 if (cgroup_parent(cgrp)) 733 __cgroup_account_cputime_field(cgrp, index, delta_exec); 734} 735 736#else /* CONFIG_CGROUPS */ 737 738static inline void cgroup_account_cputime(struct task_struct *task, 739 u64 delta_exec) {} 740static inline void cgroup_account_cputime_field(struct task_struct *task, 741 enum cpu_usage_stat index, 742 u64 delta_exec) {} 743 744#endif /* CONFIG_CGROUPS */ 745 746/* 747 * sock->sk_cgrp_data handling. For more info, see sock_cgroup_data 748 * definition in cgroup-defs.h. 749 */ 750#ifdef CONFIG_SOCK_CGROUP_DATA 751 752void cgroup_sk_alloc(struct sock_cgroup_data *skcd); 753void cgroup_sk_clone(struct sock_cgroup_data *skcd); 754void cgroup_sk_free(struct sock_cgroup_data *skcd); 755 756static inline struct cgroup *sock_cgroup_ptr(struct sock_cgroup_data *skcd) 757{ 758 return skcd->cgroup; 759} 760 761#else /* CONFIG_CGROUP_DATA */ 762 763static inline void cgroup_sk_alloc(struct sock_cgroup_data *skcd) {} 764static inline void cgroup_sk_clone(struct sock_cgroup_data *skcd) {} 765static inline void cgroup_sk_free(struct sock_cgroup_data *skcd) {} 766 767#endif /* CONFIG_CGROUP_DATA */ 768 769struct cgroup_namespace { 770 struct ns_common ns; 771 struct user_namespace *user_ns; 772 struct ucounts *ucounts; 773 struct css_set *root_cset; 774}; 775 776extern struct cgroup_namespace init_cgroup_ns; 777 778#ifdef CONFIG_CGROUPS 779 780void free_cgroup_ns(struct cgroup_namespace *ns); 781 782struct cgroup_namespace *copy_cgroup_ns(unsigned long flags, 783 struct user_namespace *user_ns, 784 struct cgroup_namespace *old_ns); 785 786int cgroup_path_ns(struct cgroup *cgrp, char *buf, size_t buflen, 787 struct cgroup_namespace *ns); 788 789#else /* !CONFIG_CGROUPS */ 790 791static inline void free_cgroup_ns(struct cgroup_namespace *ns) { } 792static inline struct cgroup_namespace * 793copy_cgroup_ns(unsigned long flags, struct user_namespace *user_ns, 794 struct cgroup_namespace *old_ns) 795{ 796 return old_ns; 797} 798 799#endif /* !CONFIG_CGROUPS */ 800 801static inline void get_cgroup_ns(struct cgroup_namespace *ns) 802{ 803 if (ns) 804 refcount_inc(&ns->ns.count); 805} 806 807static inline void put_cgroup_ns(struct cgroup_namespace *ns) 808{ 809 if (ns && refcount_dec_and_test(&ns->ns.count)) 810 free_cgroup_ns(ns); 811} 812 813#ifdef CONFIG_CGROUPS 814 815void cgroup_enter_frozen(void); 816void cgroup_leave_frozen(bool always_leave); 817void cgroup_update_frozen(struct cgroup *cgrp); 818void cgroup_freeze(struct cgroup *cgrp, bool freeze); 819void cgroup_freezer_migrate_task(struct task_struct *task, struct cgroup *src, 820 struct cgroup *dst); 821 822static inline bool cgroup_task_frozen(struct task_struct *task) 823{ 824 return task->frozen; 825} 826 827#else /* !CONFIG_CGROUPS */ 828 829static inline void cgroup_enter_frozen(void) { } 830static inline void cgroup_leave_frozen(bool always_leave) { } 831static inline bool cgroup_task_frozen(struct task_struct *task) 832{ 833 return false; 834} 835 836#endif /* !CONFIG_CGROUPS */ 837 838#ifdef CONFIG_CGROUP_BPF 839static inline void cgroup_bpf_get(struct cgroup *cgrp) 840{ 841 percpu_ref_get(&cgrp->bpf.refcnt); 842} 843 844static inline void cgroup_bpf_put(struct cgroup *cgrp) 845{ 846 percpu_ref_put(&cgrp->bpf.refcnt); 847} 848 849#else /* CONFIG_CGROUP_BPF */ 850 851static inline void cgroup_bpf_get(struct cgroup *cgrp) {} 852static inline void cgroup_bpf_put(struct cgroup *cgrp) {} 853 854#endif /* CONFIG_CGROUP_BPF */ 855 856struct cgroup *task_get_cgroup1(struct task_struct *tsk, int hierarchy_id); 857 858#endif /* _LINUX_CGROUP_H */ 859