include/linux/memcontrol.h

   1 /* memcontrol.h - Memory Controller
   2  *
   3  * Copyright IBM Corporation, 2007
   4  * Author Balbir Singh <balbir@linux.vnet.ibm.com>
   5  *
   6  * Copyright 2007 OpenVZ SWsoft Inc
   7  * Author: Pavel Emelianov <xemul@openvz.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  */
  19
  20 #ifndef _LINUX_MEMCONTROL_H
  21 #define _LINUX_MEMCONTROL_H
  22 #include <linux/cgroup.h>
  23 #include <linux/vm_event_item.h>
  24 #include <linux/hardirq.h>
  25 #include <linux/jump_label.h>
  26 #include <linux/page_counter.h>
  27 #include <linux/vmpressure.h>
  28 #include <linux/eventfd.h>
  29 #include <linux/mmzone.h>
  30 #include <linux/writeback.h>
  31 #include <linux/page-flags.h>
  32
  33 struct mem_cgroup;
  34 struct page;
  35 struct mm_struct;
  36 struct kmem_cache;
  37
  38 /*
  39  * The corresponding mem_cgroup_stat_names is defined in mm/memcontrol.c,
  40  * These two lists should keep in accord with each other.
  41  */
  42 enum mem_cgroup_stat_index {
  43         /*
  44          * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
  45          */
  46         MEM_CGROUP_STAT_CACHE,          /* # of pages charged as cache */
  47         MEM_CGROUP_STAT_RSS,            /* # of pages charged as anon rss */
  48         MEM_CGROUP_STAT_RSS_HUGE,       /* # of pages charged as anon huge */
  49         MEM_CGROUP_STAT_FILE_MAPPED,    /* # of pages charged as file rss */
  50         MEM_CGROUP_STAT_DIRTY,          /* # of dirty pages in page cache */
  51         MEM_CGROUP_STAT_WRITEBACK,      /* # of pages under writeback */
  52         MEM_CGROUP_STAT_SWAP,           /* # of pages, swapped out */
  53         MEM_CGROUP_STAT_NSTATS,
  54         /* default hierarchy stats */
  55         MEMCG_KERNEL_STACK_KB = MEM_CGROUP_STAT_NSTATS,
  56         MEMCG_SLAB_RECLAIMABLE,
  57         MEMCG_SLAB_UNRECLAIMABLE,
  58         MEMCG_SOCK,
  59         MEMCG_NR_STAT,
  60 };
  61
  62 struct mem_cgroup_reclaim_cookie {
  63         pg_data_t *pgdat;
  64         int priority;
  65         unsigned int generation;
  66 };
  67
  68 enum mem_cgroup_events_index {
  69         MEM_CGROUP_EVENTS_PGPGIN,       /* # of pages paged in */
  70         MEM_CGROUP_EVENTS_PGPGOUT,      /* # of pages paged out */
  71         MEM_CGROUP_EVENTS_PGFAULT,      /* # of page-faults */
  72         MEM_CGROUP_EVENTS_PGMAJFAULT,   /* # of major page-faults */
  73         MEM_CGROUP_EVENTS_NSTATS,
  74         /* default hierarchy events */
  75         MEMCG_LOW = MEM_CGROUP_EVENTS_NSTATS,
  76         MEMCG_HIGH,
  77         MEMCG_MAX,
  78         MEMCG_OOM,
  79         MEMCG_NR_EVENTS,
  80 };
  81
  82 /*
  83  * Per memcg event counter is incremented at every pagein/pageout. With THP,
  84  * it will be incremated by the number of pages. This counter is used for
  85  * for trigger some periodic events. This is straightforward and better
  86  * than using jiffies etc. to handle periodic memcg event.
  87  */
  88 enum mem_cgroup_events_target {
  89         MEM_CGROUP_TARGET_THRESH,
  90         MEM_CGROUP_TARGET_SOFTLIMIT,
  91         MEM_CGROUP_TARGET_NUMAINFO,
  92         MEM_CGROUP_NTARGETS,
  93 };
  94
  95 #ifdef CONFIG_MEMCG
  96
  97 #define MEM_CGROUP_ID_SHIFT     16
  98 #define MEM_CGROUP_ID_MAX       USHRT_MAX
  99
 100 struct mem_cgroup_id {
 101         int id;
 102         atomic_t ref;
 103 };
 104
 105 struct mem_cgroup_stat_cpu {
 106         long count[MEMCG_NR_STAT];
 107         unsigned long events[MEMCG_NR_EVENTS];
 108         unsigned long nr_page_events;
 109         unsigned long targets[MEM_CGROUP_NTARGETS];
 110 };
 111
 112 struct mem_cgroup_reclaim_iter {
 113         struct mem_cgroup *position;
 114         /* scan generation, increased every round-trip */
 115         unsigned int generation;
 116 };
 117
 118 /*
 119  * per-zone information in memory controller.
 120  */
 121 struct mem_cgroup_per_node {
 122         struct lruvec           lruvec;
 123         unsigned long           lru_size[NR_LRU_LISTS];
 124
 125         struct mem_cgroup_reclaim_iter  iter[DEF_PRIORITY + 1];
 126
 127         struct rb_node          tree_node;      /* RB tree node */
 128         unsigned long           usage_in_excess;/* Set to the value by which */
 129                                                 /* the soft limit is exceeded*/
 130         bool                    on_tree;
 131         struct mem_cgroup       *memcg;         /* Back pointer, we cannot */
 132                                                 /* use container_of        */
 133 };
 134
 135 struct mem_cgroup_threshold {
 136         struct eventfd_ctx *eventfd;
 137         unsigned long threshold;
 138 };
 139
 140 /* For threshold */
 141 struct mem_cgroup_threshold_ary {
 142         /* An array index points to threshold just below or equal to usage. */
 143         int current_threshold;
 144         /* Size of entries[] */
 145         unsigned int size;
 146         /* Array of thresholds */
 147         struct mem_cgroup_threshold entries[0];
 148 };
 149
 150 struct mem_cgroup_thresholds {
 151         /* Primary thresholds array */
 152         struct mem_cgroup_threshold_ary *primary;
 153         /*
 154          * Spare threshold array.
 155          * This is needed to make mem_cgroup_unregister_event() "never fail".
 156          * It must be able to store at least primary->size - 1 entries.
 157          */
 158         struct mem_cgroup_threshold_ary *spare;
 159 };
 160
 161 enum memcg_kmem_state {
 162         KMEM_NONE,
 163         KMEM_ALLOCATED,
 164         KMEM_ONLINE,
 165 };
 166
 167 /*
 168  * The memory controller data structure. The memory controller controls both
 169  * page cache and RSS per cgroup. We would eventually like to provide
 170  * statistics based on the statistics developed by Rik Van Riel for clock-pro,
 171  * to help the administrator determine what knobs to tune.
 172  */
 173 struct mem_cgroup {
 174         struct cgroup_subsys_state css;
 175
 176         /* Private memcg ID. Used to ID objects that outlive the cgroup */
 177         struct mem_cgroup_id id;
 178
 179         /* Accounted resources */
 180         struct page_counter memory;
 181         struct page_counter swap;
 182
 183         /* Legacy consumer-oriented counters */
 184         struct page_counter memsw;
 185         struct page_counter kmem;
 186         struct page_counter tcpmem;
 187
 188         /* Normal memory consumption range */
 189         unsigned long low;
 190         unsigned long high;
 191
 192         /* Range enforcement for interrupt charges */
 193         struct work_struct high_work;
 194
 195         unsigned long soft_limit;
 196
 197         /* vmpressure notifications */
 198         struct vmpressure vmpressure;
 199
 200         /*
 201          * Should the accounting and control be hierarchical, per subtree?
 202          */
 203         bool use_hierarchy;
 204
 205         /* protected by memcg_oom_lock */
 206         bool            oom_lock;
 207         int             under_oom;
 208
 209         int     swappiness;
 210         /* OOM-Killer disable */
 211         int             oom_kill_disable;
 212
 213         /* handle for "memory.events" */
 214         struct cgroup_file events_file;
 215
 216         /* protect arrays of thresholds */
 217         struct mutex thresholds_lock;
 218
 219         /* thresholds for memory usage. RCU-protected */
 220         struct mem_cgroup_thresholds thresholds;
 221
 222         /* thresholds for mem+swap usage. RCU-protected */
 223         struct mem_cgroup_thresholds memsw_thresholds;
 224
 225         /* For oom notifier event fd */
 226         struct list_head oom_notify;
 227
 228         /*
 229          * Should we move charges of a task when a task is moved into this
 230          * mem_cgroup ? And what type of charges should we move ?
 231          */
 232         unsigned long move_charge_at_immigrate;
 233         /*
 234          * set > 0 if pages under this cgroup are moving to other cgroup.
 235          */
 236         atomic_t                moving_account;
 237         /* taken only while moving_account > 0 */
 238         spinlock_t              move_lock;
 239         struct task_struct      *move_lock_task;
 240         unsigned long           move_lock_flags;
 241         /*
 242          * percpu counter.
 243          */
 244         struct mem_cgroup_stat_cpu __percpu *stat;
 245
 246         unsigned long           socket_pressure;
 247
 248         /* Legacy tcp memory accounting */
 249         bool                    tcpmem_active;
 250         int                     tcpmem_pressure;
 251
 252 #ifndef CONFIG_SLOB
 253         /* Index in the kmem_cache->memcg_params.memcg_caches array */
 254         int kmemcg_id;
 255         enum memcg_kmem_state kmem_state;
 256 #endif
 257
 258         int last_scanned_node;
 259 #if MAX_NUMNODES > 1
 260         nodemask_t      scan_nodes;
 261         atomic_t        numainfo_events;
 262         atomic_t        numainfo_updating;
 263 #endif
 264
 265 #ifdef CONFIG_CGROUP_WRITEBACK
 266         struct list_head cgwb_list;
 267         struct wb_domain cgwb_domain;
 268 #endif
 269
 270         /* List of events which userspace want to receive */
 271         struct list_head event_list;
 272         spinlock_t event_list_lock;
 273
 274         struct mem_cgroup_per_node *nodeinfo[0];
 275         /* WARNING: nodeinfo must be the last member here */
 276 };
 277
 278 extern struct mem_cgroup *root_mem_cgroup;
 279
 280 static inline bool mem_cgroup_disabled(void)
 281 {
 282         return !cgroup_subsys_enabled(memory_cgrp_subsys);
 283 }
 284
 285 /**
 286  * mem_cgroup_events - count memory events against a cgroup
 287  * @memcg: the memory cgroup
 288  * @idx: the event index
 289  * @nr: the number of events to account for
 290  */
 291 static inline void mem_cgroup_events(struct mem_cgroup *memcg,
 292                        enum mem_cgroup_events_index idx,
 293                        unsigned int nr)
 294 {
 295         this_cpu_add(memcg->stat->events[idx], nr);
 296         cgroup_file_notify(&memcg->events_file);
 297 }
 298
 299 bool mem_cgroup_low(struct mem_cgroup *root, struct mem_cgroup *memcg);
 300
 301 int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
 302                           gfp_t gfp_mask, struct mem_cgroup **memcgp,
 303                           bool compound);
 304 void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
 305                               bool lrucare, bool compound);
 306 void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg,
 307                 bool compound);
 308 void mem_cgroup_uncharge(struct page *page);
 309 void mem_cgroup_uncharge_list(struct list_head *page_list);
 310
 311 void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
 312
 313 static struct mem_cgroup_per_node *
 314 mem_cgroup_nodeinfo(struct mem_cgroup *memcg, int nid)
 315 {
 316         return memcg->nodeinfo[nid];
 317 }
 318
 319 /**
 320  * mem_cgroup_lruvec - get the lru list vector for a node or a memcg zone
 321  * @node: node of the wanted lruvec
 322  * @memcg: memcg of the wanted lruvec
 323  *
 324  * Returns the lru list vector holding pages for a given @node or a given
 325  * @memcg and @zone. This can be the node lruvec, if the memory controller
 326  * is disabled.
 327  */
 328 static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
 329                                 struct mem_cgroup *memcg)
 330 {
 331         struct mem_cgroup_per_node *mz;
 332         struct lruvec *lruvec;
 333
 334         if (mem_cgroup_disabled()) {
 335                 lruvec = node_lruvec(pgdat);
 336                 goto out;
 337         }
 338
 339         mz = mem_cgroup_nodeinfo(memcg, pgdat->node_id);
 340         lruvec = &mz->lruvec;
 341 out:
 342         /*
 343          * Since a node can be onlined after the mem_cgroup was created,
 344          * we have to be prepared to initialize lruvec->pgdat here;
 345          * and if offlined then reonlined, we need to reinitialize it.
 346          */
 347         if (unlikely(lruvec->pgdat != pgdat))
 348                 lruvec->pgdat = pgdat;
 349         return lruvec;
 350 }
 351
 352 struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *);
 353
 354 bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg);
 355 struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
 356
 357 static inline
 358 struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css){
 359         return css ? container_of(css, struct mem_cgroup, css) : NULL;
 360 }
 361
 362 #define mem_cgroup_from_counter(counter, member)        \
 363         container_of(counter, struct mem_cgroup, member)
 364
 365 struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *,
 366                                    struct mem_cgroup *,
 367                                    struct mem_cgroup_reclaim_cookie *);
 368 void mem_cgroup_iter_break(struct mem_cgroup *, struct mem_cgroup *);
 369
 370 static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
 371 {
 372         if (mem_cgroup_disabled())
 373                 return 0;
 374
 375         return memcg->id.id;
 376 }
 377 struct mem_cgroup *mem_cgroup_from_id(unsigned short id);
 378
 379 /**
 380  * parent_mem_cgroup - find the accounting parent of a memcg
 381  * @memcg: memcg whose parent to find
 382  *
 383  * Returns the parent memcg, or NULL if this is the root or the memory
 384  * controller is in legacy no-hierarchy mode.
 385  */
 386 static inline struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg)
 387 {
 388         if (!memcg->memory.parent)
 389                 return NULL;
 390         return mem_cgroup_from_counter(memcg->memory.parent, memory);
 391 }
 392
 393 static inline bool mem_cgroup_is_descendant(struct mem_cgroup *memcg,
 394                               struct mem_cgroup *root)
 395 {
 396         if (root == memcg)
 397                 return true;
 398         if (!root->use_hierarchy)
 399                 return false;
 400         return cgroup_is_descendant(memcg->css.cgroup, root->css.cgroup);
 401 }
 402
 403 static inline bool mm_match_cgroup(struct mm_struct *mm,
 404                                    struct mem_cgroup *memcg)
 405 {
 406         struct mem_cgroup *task_memcg;
 407         bool match = false;
 408
 409         rcu_read_lock();
 410         task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
 411         if (task_memcg)
 412                 match = mem_cgroup_is_descendant(task_memcg, memcg);
 413         rcu_read_unlock();
 414         return match;
 415 }
 416
 417 struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page);
 418 ino_t page_cgroup_ino(struct page *page);
 419
 420 static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
 421 {
 422         if (mem_cgroup_disabled())
 423                 return true;
 424         return !!(memcg->css.flags & CSS_ONLINE);
 425 }
 426
 427 /*
 428  * For memory reclaim.
 429  */
 430 int mem_cgroup_select_victim_node(struct mem_cgroup *memcg);
 431
 432 void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
 433                 int nr_pages);
 434
 435 unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg,
 436                                            int nid, unsigned int lru_mask);
 437
 438 static inline
 439 unsigned long mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
 440 {
 441         struct mem_cgroup_per_node *mz;
 442
 443         mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
 444         return mz->lru_size[lru];
 445 }
 446
 447 void mem_cgroup_handle_over_high(void);
 448
 449 void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
 450                                 struct task_struct *p);
 451
 452 static inline void mem_cgroup_oom_enable(void)
 453 {
 454         WARN_ON(current->memcg_may_oom);
 455         current->memcg_may_oom = 1;
 456 }
 457
 458 static inline void mem_cgroup_oom_disable(void)
 459 {
 460         WARN_ON(!current->memcg_may_oom);
 461         current->memcg_may_oom = 0;
 462 }
 463
 464 static inline bool task_in_memcg_oom(struct task_struct *p)
 465 {
 466         return p->memcg_in_oom;
 467 }
 468
 469 bool mem_cgroup_oom_synchronize(bool wait);
 470
 471 #ifdef CONFIG_MEMCG_SWAP
 472 extern int do_swap_account;
 473 #endif
 474
 475 void lock_page_memcg(struct page *page);
 476 void unlock_page_memcg(struct page *page);
 477
 478 /**
 479  * mem_cgroup_update_page_stat - update page state statistics
 480  * @page: the page
 481  * @idx: page state item to account
 482  * @val: number of pages (positive or negative)
 483  *
 484  * The @page must be locked or the caller must use lock_page_memcg()
 485  * to prevent double accounting when the page is concurrently being
 486  * moved to another memcg:
 487  *
 488  *   lock_page(page) or lock_page_memcg(page)
 489  *   if (TestClearPageState(page))
 490  *     mem_cgroup_update_page_stat(page, state, -1);
 491  *   unlock_page(page) or unlock_page_memcg(page)
 492  */
 493 static inline void mem_cgroup_update_page_stat(struct page *page,
 494                                  enum mem_cgroup_stat_index idx, int val)
 495 {
 496         VM_BUG_ON(!(rcu_read_lock_held() || PageLocked(page)));
 497
 498         if (page->mem_cgroup)
 499                 this_cpu_add(page->mem_cgroup->stat->count[idx], val);
 500 }
 501
 502 static inline void mem_cgroup_inc_page_stat(struct page *page,
 503                                             enum mem_cgroup_stat_index idx)
 504 {
 505         mem_cgroup_update_page_stat(page, idx, 1);
 506 }
 507
 508 static inline void mem_cgroup_dec_page_stat(struct page *page,
 509                                             enum mem_cgroup_stat_index idx)
 510 {
 511         mem_cgroup_update_page_stat(page, idx, -1);
 512 }
 513
 514 unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
 515                                                 gfp_t gfp_mask,
 516                                                 unsigned long *total_scanned);
 517
 518 static inline void mem_cgroup_count_vm_event(struct mm_struct *mm,
 519                                              enum vm_event_item idx)
 520 {
 521         struct mem_cgroup *memcg;
 522
 523         if (mem_cgroup_disabled())
 524                 return;
 525
 526         rcu_read_lock();
 527         memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
 528         if (unlikely(!memcg))
 529                 goto out;
 530
 531         switch (idx) {
 532         case PGFAULT:
 533                 this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT]);
 534                 break;
 535         case PGMAJFAULT:
 536                 this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT]);
 537                 break;
 538         default:
 539                 BUG();
 540         }
 541 out:
 542         rcu_read_unlock();
 543 }
 544 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 545 void mem_cgroup_split_huge_fixup(struct page *head);
 546 #endif
 547
 548 #else /* CONFIG_MEMCG */
 549
 550 #define MEM_CGROUP_ID_SHIFT     0
 551 #define MEM_CGROUP_ID_MAX       0
 552
 553 struct mem_cgroup;
 554
 555 static inline bool mem_cgroup_disabled(void)
 556 {
 557         return true;
 558 }
 559
 560 static inline void mem_cgroup_events(struct mem_cgroup *memcg,
 561                                      enum mem_cgroup_events_index idx,
 562                                      unsigned int nr)
 563 {
 564 }
 565
 566 static inline bool mem_cgroup_low(struct mem_cgroup *root,
 567                                   struct mem_cgroup *memcg)
 568 {
 569         return false;
 570 }
 571
 572 static inline int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
 573                                         gfp_t gfp_mask,
 574                                         struct mem_cgroup **memcgp,
 575                                         bool compound)
 576 {
 577         *memcgp = NULL;
 578         return 0;
 579 }
 580
 581 static inline void mem_cgroup_commit_charge(struct page *page,
 582                                             struct mem_cgroup *memcg,
 583                                             bool lrucare, bool compound)
 584 {
 585 }
 586
 587 static inline void mem_cgroup_cancel_charge(struct page *page,
 588                                             struct mem_cgroup *memcg,
 589                                             bool compound)
 590 {
 591 }
 592
 593 static inline void mem_cgroup_uncharge(struct page *page)
 594 {
 595 }
 596
 597 static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
 598 {
 599 }
 600
 601 static inline void mem_cgroup_migrate(struct page *old, struct page *new)
 602 {
 603 }
 604
 605 static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
 606                                 struct mem_cgroup *memcg)
 607 {
 608         return node_lruvec(pgdat);
 609 }
 610
 611 static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
 612                                                     struct pglist_data *pgdat)
 613 {
 614         return &pgdat->lruvec;
 615 }
 616
 617 static inline bool mm_match_cgroup(struct mm_struct *mm,
 618                 struct mem_cgroup *memcg)
 619 {
 620         return true;
 621 }
 622
 623 static inline bool task_in_mem_cgroup(struct task_struct *task,
 624                                       const struct mem_cgroup *memcg)
 625 {
 626         return true;
 627 }
 628
 629 static inline struct mem_cgroup *
 630 mem_cgroup_iter(struct mem_cgroup *root,
 631                 struct mem_cgroup *prev,
 632                 struct mem_cgroup_reclaim_cookie *reclaim)
 633 {
 634         return NULL;
 635 }
 636
 637 static inline void mem_cgroup_iter_break(struct mem_cgroup *root,
 638                                          struct mem_cgroup *prev)
 639 {
 640 }
 641
 642 static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
 643 {
 644         return 0;
 645 }
 646
 647 static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
 648 {
 649         WARN_ON_ONCE(id);
 650         /* XXX: This should always return root_mem_cgroup */
 651         return NULL;
 652 }
 653
 654 static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
 655 {
 656         return true;
 657 }
 658
 659 static inline unsigned long
 660 mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
 661 {
 662         return 0;
 663 }
 664
 665 static inline unsigned long
 666 mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg,
 667                              int nid, unsigned int lru_mask)
 668 {
 669         return 0;
 670 }
 671
 672 static inline void
 673 mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
 674 {
 675 }
 676
 677 static inline void lock_page_memcg(struct page *page)
 678 {
 679 }
 680
 681 static inline void unlock_page_memcg(struct page *page)
 682 {
 683 }
 684
 685 static inline void mem_cgroup_handle_over_high(void)
 686 {
 687 }
 688
 689 static inline void mem_cgroup_oom_enable(void)
 690 {
 691 }
 692
 693 static inline void mem_cgroup_oom_disable(void)
 694 {
 695 }
 696
 697 static inline bool task_in_memcg_oom(struct task_struct *p)
 698 {
 699         return false;
 700 }
 701
 702 static inline bool mem_cgroup_oom_synchronize(bool wait)
 703 {
 704         return false;
 705 }
 706
 707 static inline void mem_cgroup_inc_page_stat(struct page *page,
 708                                             enum mem_cgroup_stat_index idx)
 709 {
 710 }
 711
 712 static inline void mem_cgroup_dec_page_stat(struct page *page,
 713                                             enum mem_cgroup_stat_index idx)
 714 {
 715 }
 716
 717 static inline
 718 unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
 719                                             gfp_t gfp_mask,
 720                                             unsigned long *total_scanned)
 721 {
 722         return 0;
 723 }
 724
 725 static inline void mem_cgroup_split_huge_fixup(struct page *head)
 726 {
 727 }
 728
 729 static inline
 730 void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
 731 {
 732 }
 733 #endif /* CONFIG_MEMCG */
 734
 735 #ifdef CONFIG_CGROUP_WRITEBACK
 736
 737 struct list_head *mem_cgroup_cgwb_list(struct mem_cgroup *memcg);
 738 struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb);
 739 void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
 740                          unsigned long *pheadroom, unsigned long *pdirty,
 741                          unsigned long *pwriteback);
 742
 743 #else   /* CONFIG_CGROUP_WRITEBACK */
 744
 745 static inline struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb)
 746 {
 747         return NULL;
 748 }
 749
 750 static inline void mem_cgroup_wb_stats(struct bdi_writeback *wb,
 751                                        unsigned long *pfilepages,
 752                                        unsigned long *pheadroom,
 753                                        unsigned long *pdirty,
 754                                        unsigned long *pwriteback)
 755 {
 756 }
 757
 758 #endif  /* CONFIG_CGROUP_WRITEBACK */
 759
 760 struct sock;
 761 void sock_update_memcg(struct sock *sk);
 762 void sock_release_memcg(struct sock *sk);
 763 bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
 764 void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
 765 #ifdef CONFIG_MEMCG
 766 extern struct static_key_false memcg_sockets_enabled_key;
 767 #define mem_cgroup_sockets_enabled static_branch_unlikely(&memcg_sockets_enabled_key)
 768 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
 769 {
 770         if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_pressure)
 771                 return true;
 772         do {
 773                 if (time_before(jiffies, memcg->socket_pressure))
 774                         return true;
 775         } while ((memcg = parent_mem_cgroup(memcg)));
 776         return false;
 777 }
 778 #else
 779 #define mem_cgroup_sockets_enabled 0
 780 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
 781 {
 782         return false;
 783 }
 784 #endif
 785
 786 struct kmem_cache *memcg_kmem_get_cache(struct kmem_cache *cachep);
 787 void memcg_kmem_put_cache(struct kmem_cache *cachep);
 788 int memcg_kmem_charge_memcg(struct page *page, gfp_t gfp, int order,
 789                             struct mem_cgroup *memcg);
 790 int memcg_kmem_charge(struct page *page, gfp_t gfp, int order);
 791 void memcg_kmem_uncharge(struct page *page, int order);
 792
 793 #if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
 794 extern struct static_key_false memcg_kmem_enabled_key;
 795
 796 extern int memcg_nr_cache_ids;
 797 void memcg_get_cache_ids(void);
 798 void memcg_put_cache_ids(void);
 799
 800 /*
 801  * Helper macro to loop through all memcg-specific caches. Callers must still
 802  * check if the cache is valid (it is either valid or NULL).
 803  * the slab_mutex must be held when looping through those caches
 804  */
 805 #define for_each_memcg_cache_index(_idx)        \
 806         for ((_idx) = 0; (_idx) < memcg_nr_cache_ids; (_idx)++)
 807
 808 static inline bool memcg_kmem_enabled(void)
 809 {
 810         return static_branch_unlikely(&memcg_kmem_enabled_key);
 811 }
 812
 813 /*
 814  * helper for accessing a memcg's index. It will be used as an index in the
 815  * child cache array in kmem_cache, and also to derive its name. This function
 816  * will return -1 when this is not a kmem-limited memcg.
 817  */
 818 static inline int memcg_cache_id(struct mem_cgroup *memcg)
 819 {
 820         return memcg ? memcg->kmemcg_id : -1;
 821 }
 822
 823 /**
 824  * memcg_kmem_update_page_stat - update kmem page state statistics
 825  * @page: the page
 826  * @idx: page state item to account
 827  * @val: number of pages (positive or negative)
 828  */
 829 static inline void memcg_kmem_update_page_stat(struct page *page,
 830                                 enum mem_cgroup_stat_index idx, int val)
 831 {
 832         if (memcg_kmem_enabled() && page->mem_cgroup)
 833                 this_cpu_add(page->mem_cgroup->stat->count[idx], val);
 834 }
 835
 836 #else
 837 #define for_each_memcg_cache_index(_idx)        \
 838         for (; NULL; )
 839
 840 static inline bool memcg_kmem_enabled(void)
 841 {
 842         return false;
 843 }
 844
 845 static inline int memcg_cache_id(struct mem_cgroup *memcg)
 846 {
 847         return -1;
 848 }
 849
 850 static inline void memcg_get_cache_ids(void)
 851 {
 852 }
 853
 854 static inline void memcg_put_cache_ids(void)
 855 {
 856 }
 857
 858 static inline void memcg_kmem_update_page_stat(struct page *page,
 859                                 enum mem_cgroup_stat_index idx, int val)
 860 {
 861 }
 862 #endif /* CONFIG_MEMCG && !CONFIG_SLOB */
 863
 864 #endif /* _LINUX_MEMCONTROL_H */