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_SHMEM,          /* # of pages charged as shmem */
  50         MEM_CGROUP_STAT_FILE_MAPPED,    /* # of pages charged as file rss */
  51         MEM_CGROUP_STAT_DIRTY,          /* # of dirty pages in page cache */
  52         MEM_CGROUP_STAT_WRITEBACK,      /* # of pages under writeback */
  53         MEM_CGROUP_STAT_SWAP,           /* # of pages, swapped out */
  54         MEM_CGROUP_STAT_NSTATS,
  55         /* default hierarchy stats */
  56         MEMCG_KERNEL_STACK_KB = MEM_CGROUP_STAT_NSTATS,
  57         MEMCG_SLAB_RECLAIMABLE,
  58         MEMCG_SLAB_UNRECLAIMABLE,
  59         MEMCG_SOCK,
  60         MEMCG_WORKINGSET_REFAULT,
  61         MEMCG_WORKINGSET_ACTIVATE,
  62         MEMCG_WORKINGSET_NODERECLAIM,
  63         MEMCG_NR_STAT,
  64 };
  65
  66 struct mem_cgroup_reclaim_cookie {
  67         pg_data_t *pgdat;
  68         int priority;
  69         unsigned int generation;
  70 };
  71
  72 enum mem_cgroup_events_index {
  73         MEM_CGROUP_EVENTS_PGPGIN,       /* # of pages paged in */
  74         MEM_CGROUP_EVENTS_PGPGOUT,      /* # of pages paged out */
  75         MEM_CGROUP_EVENTS_PGFAULT,      /* # of page-faults */
  76         MEM_CGROUP_EVENTS_PGMAJFAULT,   /* # of major page-faults */
  77         MEM_CGROUP_EVENTS_NSTATS,
  78         /* default hierarchy events */
  79         MEMCG_LOW = MEM_CGROUP_EVENTS_NSTATS,
  80         MEMCG_HIGH,
  81         MEMCG_MAX,
  82         MEMCG_OOM,
  83         MEMCG_NR_EVENTS,
  84 };
  85
  86 /*
  87  * Per memcg event counter is incremented at every pagein/pageout. With THP,
  88  * it will be incremated by the number of pages. This counter is used for
  89  * for trigger some periodic events. This is straightforward and better
  90  * than using jiffies etc. to handle periodic memcg event.
  91  */
  92 enum mem_cgroup_events_target {
  93         MEM_CGROUP_TARGET_THRESH,
  94         MEM_CGROUP_TARGET_SOFTLIMIT,
  95         MEM_CGROUP_TARGET_NUMAINFO,
  96         MEM_CGROUP_NTARGETS,
  97 };
  98
  99 #ifdef CONFIG_MEMCG
 100
 101 #define MEM_CGROUP_ID_SHIFT     16
 102 #define MEM_CGROUP_ID_MAX       USHRT_MAX
 103
 104 struct mem_cgroup_id {
 105         int id;
 106         atomic_t ref;
 107 };
 108
 109 struct mem_cgroup_stat_cpu {
 110         long count[MEMCG_NR_STAT];
 111         unsigned long events[MEMCG_NR_EVENTS];
 112         unsigned long nr_page_events;
 113         unsigned long targets[MEM_CGROUP_NTARGETS];
 114 };
 115
 116 struct mem_cgroup_reclaim_iter {
 117         struct mem_cgroup *position;
 118         /* scan generation, increased every round-trip */
 119         unsigned int generation;
 120 };
 121
 122 /*
 123  * per-zone information in memory controller.
 124  */
 125 struct mem_cgroup_per_node {
 126         struct lruvec           lruvec;
 127         unsigned long           lru_zone_size[MAX_NR_ZONES][NR_LRU_LISTS];
 128
 129         struct mem_cgroup_reclaim_iter  iter[DEF_PRIORITY + 1];
 130
 131         struct rb_node          tree_node;      /* RB tree node */
 132         unsigned long           usage_in_excess;/* Set to the value by which */
 133                                                 /* the soft limit is exceeded*/
 134         bool                    on_tree;
 135         struct mem_cgroup       *memcg;         /* Back pointer, we cannot */
 136                                                 /* use container_of        */
 137 };
 138
 139 struct mem_cgroup_threshold {
 140         struct eventfd_ctx *eventfd;
 141         unsigned long threshold;
 142 };
 143
 144 /* For threshold */
 145 struct mem_cgroup_threshold_ary {
 146         /* An array index points to threshold just below or equal to usage. */
 147         int current_threshold;
 148         /* Size of entries[] */
 149         unsigned int size;
 150         /* Array of thresholds */
 151         struct mem_cgroup_threshold entries[0];
 152 };
 153
 154 struct mem_cgroup_thresholds {
 155         /* Primary thresholds array */
 156         struct mem_cgroup_threshold_ary *primary;
 157         /*
 158          * Spare threshold array.
 159          * This is needed to make mem_cgroup_unregister_event() "never fail".
 160          * It must be able to store at least primary->size - 1 entries.
 161          */
 162         struct mem_cgroup_threshold_ary *spare;
 163 };
 164
 165 enum memcg_kmem_state {
 166         KMEM_NONE,
 167         KMEM_ALLOCATED,
 168         KMEM_ONLINE,
 169 };
 170
 171 /*
 172  * The memory controller data structure. The memory controller controls both
 173  * page cache and RSS per cgroup. We would eventually like to provide
 174  * statistics based on the statistics developed by Rik Van Riel for clock-pro,
 175  * to help the administrator determine what knobs to tune.
 176  */
 177 struct mem_cgroup {
 178         struct cgroup_subsys_state css;
 179
 180         /* Private memcg ID. Used to ID objects that outlive the cgroup */
 181         struct mem_cgroup_id id;
 182
 183         /* Accounted resources */
 184         struct page_counter memory;
 185         struct page_counter swap;
 186
 187         /* Legacy consumer-oriented counters */
 188         struct page_counter memsw;
 189         struct page_counter kmem;
 190         struct page_counter tcpmem;
 191
 192         /* Normal memory consumption range */
 193         unsigned long low;
 194         unsigned long high;
 195
 196         /* Range enforcement for interrupt charges */
 197         struct work_struct high_work;
 198
 199         unsigned long soft_limit;
 200
 201         /* vmpressure notifications */
 202         struct vmpressure vmpressure;
 203
 204         /*
 205          * Should the accounting and control be hierarchical, per subtree?
 206          */
 207         bool use_hierarchy;
 208
 209         /* protected by memcg_oom_lock */
 210         bool            oom_lock;
 211         int             under_oom;
 212
 213         int     swappiness;
 214         /* OOM-Killer disable */
 215         int             oom_kill_disable;
 216
 217         /* handle for "memory.events" */
 218         struct cgroup_file events_file;
 219
 220         /* protect arrays of thresholds */
 221         struct mutex thresholds_lock;
 222
 223         /* thresholds for memory usage. RCU-protected */
 224         struct mem_cgroup_thresholds thresholds;
 225
 226         /* thresholds for mem+swap usage. RCU-protected */
 227         struct mem_cgroup_thresholds memsw_thresholds;
 228
 229         /* For oom notifier event fd */
 230         struct list_head oom_notify;
 231
 232         /*
 233          * Should we move charges of a task when a task is moved into this
 234          * mem_cgroup ? And what type of charges should we move ?
 235          */
 236         unsigned long move_charge_at_immigrate;
 237         /*
 238          * set > 0 if pages under this cgroup are moving to other cgroup.
 239          */
 240         atomic_t                moving_account;
 241         /* taken only while moving_account > 0 */
 242         spinlock_t              move_lock;
 243         struct task_struct      *move_lock_task;
 244         unsigned long           move_lock_flags;
 245         /*
 246          * percpu counter.
 247          */
 248         struct mem_cgroup_stat_cpu __percpu *stat;
 249
 250         unsigned long           socket_pressure;
 251
 252         /* Legacy tcp memory accounting */
 253         bool                    tcpmem_active;
 254         int                     tcpmem_pressure;
 255
 256 #ifndef CONFIG_SLOB
 257         /* Index in the kmem_cache->memcg_params.memcg_caches array */
 258         int kmemcg_id;
 259         enum memcg_kmem_state kmem_state;
 260         struct list_head kmem_caches;
 261 #endif
 262
 263         int last_scanned_node;
 264 #if MAX_NUMNODES > 1
 265         nodemask_t      scan_nodes;
 266         atomic_t        numainfo_events;
 267         atomic_t        numainfo_updating;
 268 #endif
 269
 270 #ifdef CONFIG_CGROUP_WRITEBACK
 271         struct list_head cgwb_list;
 272         struct wb_domain cgwb_domain;
 273 #endif
 274
 275         /* List of events which userspace want to receive */
 276         struct list_head event_list;
 277         spinlock_t event_list_lock;
 278
 279         struct mem_cgroup_per_node *nodeinfo[0];
 280         /* WARNING: nodeinfo must be the last member here */
 281 };
 282
 283 extern struct mem_cgroup *root_mem_cgroup;
 284
 285 static inline bool mem_cgroup_disabled(void)
 286 {
 287         return !cgroup_subsys_enabled(memory_cgrp_subsys);
 288 }
 289
 290 static inline void mem_cgroup_event(struct mem_cgroup *memcg,
 291                                     enum mem_cgroup_events_index idx)
 292 {
 293         this_cpu_inc(memcg->stat->events[idx]);
 294         cgroup_file_notify(&memcg->events_file);
 295 }
 296
 297 bool mem_cgroup_low(struct mem_cgroup *root, struct mem_cgroup *memcg);
 298
 299 int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
 300                           gfp_t gfp_mask, struct mem_cgroup **memcgp,
 301                           bool compound);
 302 void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
 303                               bool lrucare, bool compound);
 304 void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg,
 305                 bool compound);
 306 void mem_cgroup_uncharge(struct page *page);
 307 void mem_cgroup_uncharge_list(struct list_head *page_list);
 308
 309 void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
 310
 311 static struct mem_cgroup_per_node *
 312 mem_cgroup_nodeinfo(struct mem_cgroup *memcg, int nid)
 313 {
 314         return memcg->nodeinfo[nid];
 315 }
 316
 317 /**
 318  * mem_cgroup_lruvec - get the lru list vector for a node or a memcg zone
 319  * @node: node of the wanted lruvec
 320  * @memcg: memcg of the wanted lruvec
 321  *
 322  * Returns the lru list vector holding pages for a given @node or a given
 323  * @memcg and @zone. This can be the node lruvec, if the memory controller
 324  * is disabled.
 325  */
 326 static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
 327                                 struct mem_cgroup *memcg)
 328 {
 329         struct mem_cgroup_per_node *mz;
 330         struct lruvec *lruvec;
 331
 332         if (mem_cgroup_disabled()) {
 333                 lruvec = node_lruvec(pgdat);
 334                 goto out;
 335         }
 336
 337         mz = mem_cgroup_nodeinfo(memcg, pgdat->node_id);
 338         lruvec = &mz->lruvec;
 339 out:
 340         /*
 341          * Since a node can be onlined after the mem_cgroup was created,
 342          * we have to be prepared to initialize lruvec->pgdat here;
 343          * and if offlined then reonlined, we need to reinitialize it.
 344          */
 345         if (unlikely(lruvec->pgdat != pgdat))
 346                 lruvec->pgdat = pgdat;
 347         return lruvec;
 348 }
 349
 350 struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *);
 351
 352 bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg);
 353 struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
 354
 355 static inline
 356 struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css){
 357         return css ? container_of(css, struct mem_cgroup, css) : NULL;
 358 }
 359
 360 #define mem_cgroup_from_counter(counter, member)        \
 361         container_of(counter, struct mem_cgroup, member)
 362
 363 struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *,
 364                                    struct mem_cgroup *,
 365                                    struct mem_cgroup_reclaim_cookie *);
 366 void mem_cgroup_iter_break(struct mem_cgroup *, struct mem_cgroup *);
 367 int mem_cgroup_scan_tasks(struct mem_cgroup *,
 368                           int (*)(struct task_struct *, void *), void *);
 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 zid, 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         unsigned long nr_pages = 0;
 443         int zid;
 444
 445         mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
 446         for (zid = 0; zid < MAX_NR_ZONES; zid++)
 447                 nr_pages += mz->lru_zone_size[zid][lru];
 448         return nr_pages;
 449 }
 450
 451 static inline
 452 unsigned long mem_cgroup_get_zone_lru_size(struct lruvec *lruvec,
 453                 enum lru_list lru, int zone_idx)
 454 {
 455         struct mem_cgroup_per_node *mz;
 456
 457         mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
 458         return mz->lru_zone_size[zone_idx][lru];
 459 }
 460
 461 void mem_cgroup_handle_over_high(void);
 462
 463 unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg);
 464
 465 void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
 466                                 struct task_struct *p);
 467
 468 static inline void mem_cgroup_oom_enable(void)
 469 {
 470         WARN_ON(current->memcg_may_oom);
 471         current->memcg_may_oom = 1;
 472 }
 473
 474 static inline void mem_cgroup_oom_disable(void)
 475 {
 476         WARN_ON(!current->memcg_may_oom);
 477         current->memcg_may_oom = 0;
 478 }
 479
 480 static inline bool task_in_memcg_oom(struct task_struct *p)
 481 {
 482         return p->memcg_in_oom;
 483 }
 484
 485 bool mem_cgroup_oom_synchronize(bool wait);
 486
 487 #ifdef CONFIG_MEMCG_SWAP
 488 extern int do_swap_account;
 489 #endif
 490
 491 void lock_page_memcg(struct page *page);
 492 void unlock_page_memcg(struct page *page);
 493
 494 static inline unsigned long mem_cgroup_read_stat(struct mem_cgroup *memcg,
 495                                                  enum mem_cgroup_stat_index idx)
 496 {
 497         long val = 0;
 498         int cpu;
 499
 500         for_each_possible_cpu(cpu)
 501                 val += per_cpu(memcg->stat->count[idx], cpu);
 502
 503         if (val < 0)
 504                 val = 0;
 505
 506         return val;
 507 }
 508
 509 static inline void mem_cgroup_update_stat(struct mem_cgroup *memcg,
 510                                    enum mem_cgroup_stat_index idx, int val)
 511 {
 512         if (!mem_cgroup_disabled())
 513                 this_cpu_add(memcg->stat->count[idx], val);
 514 }
 515
 516 static inline void mem_cgroup_inc_stat(struct mem_cgroup *memcg,
 517                                    enum mem_cgroup_stat_index idx)
 518 {
 519         mem_cgroup_update_stat(memcg, idx, 1);
 520 }
 521
 522 static inline void mem_cgroup_dec_stat(struct mem_cgroup *memcg,
 523                                    enum mem_cgroup_stat_index idx)
 524 {
 525         mem_cgroup_update_stat(memcg, idx, -1);
 526 }
 527
 528 /**
 529  * mem_cgroup_update_page_stat - update page state statistics
 530  * @page: the page
 531  * @idx: page state item to account
 532  * @val: number of pages (positive or negative)
 533  *
 534  * The @page must be locked or the caller must use lock_page_memcg()
 535  * to prevent double accounting when the page is concurrently being
 536  * moved to another memcg:
 537  *
 538  *   lock_page(page) or lock_page_memcg(page)
 539  *   if (TestClearPageState(page))
 540  *     mem_cgroup_update_page_stat(page, state, -1);
 541  *   unlock_page(page) or unlock_page_memcg(page)
 542  *
 543  * Kernel pages are an exception to this, since they'll never move.
 544  */
 545 static inline void mem_cgroup_update_page_stat(struct page *page,
 546                                  enum mem_cgroup_stat_index idx, int val)
 547 {
 548         if (page->mem_cgroup)
 549                 mem_cgroup_update_stat(page->mem_cgroup, idx, val);
 550 }
 551
 552 static inline void mem_cgroup_inc_page_stat(struct page *page,
 553                                             enum mem_cgroup_stat_index idx)
 554 {
 555         mem_cgroup_update_page_stat(page, idx, 1);
 556 }
 557
 558 static inline void mem_cgroup_dec_page_stat(struct page *page,
 559                                             enum mem_cgroup_stat_index idx)
 560 {
 561         mem_cgroup_update_page_stat(page, idx, -1);
 562 }
 563
 564 unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
 565                                                 gfp_t gfp_mask,
 566                                                 unsigned long *total_scanned);
 567
 568 static inline void mem_cgroup_count_vm_event(struct mm_struct *mm,
 569                                              enum vm_event_item idx)
 570 {
 571         struct mem_cgroup *memcg;
 572
 573         if (mem_cgroup_disabled())
 574                 return;
 575
 576         rcu_read_lock();
 577         memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
 578         if (unlikely(!memcg))
 579                 goto out;
 580
 581         switch (idx) {
 582         case PGFAULT:
 583                 this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT]);
 584                 break;
 585         case PGMAJFAULT:
 586                 this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT]);
 587                 break;
 588         default:
 589                 BUG();
 590         }
 591 out:
 592         rcu_read_unlock();
 593 }
 594 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 595 void mem_cgroup_split_huge_fixup(struct page *head);
 596 #endif
 597
 598 #else /* CONFIG_MEMCG */
 599
 600 #define MEM_CGROUP_ID_SHIFT     0
 601 #define MEM_CGROUP_ID_MAX       0
 602
 603 struct mem_cgroup;
 604
 605 static inline bool mem_cgroup_disabled(void)
 606 {
 607         return true;
 608 }
 609
 610 static inline void mem_cgroup_event(struct mem_cgroup *memcg,
 611                                     enum mem_cgroup_events_index idx)
 612 {
 613 }
 614
 615 static inline bool mem_cgroup_low(struct mem_cgroup *root,
 616                                   struct mem_cgroup *memcg)
 617 {
 618         return false;
 619 }
 620
 621 static inline int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
 622                                         gfp_t gfp_mask,
 623                                         struct mem_cgroup **memcgp,
 624                                         bool compound)
 625 {
 626         *memcgp = NULL;
 627         return 0;
 628 }
 629
 630 static inline void mem_cgroup_commit_charge(struct page *page,
 631                                             struct mem_cgroup *memcg,
 632                                             bool lrucare, bool compound)
 633 {
 634 }
 635
 636 static inline void mem_cgroup_cancel_charge(struct page *page,
 637                                             struct mem_cgroup *memcg,
 638                                             bool compound)
 639 {
 640 }
 641
 642 static inline void mem_cgroup_uncharge(struct page *page)
 643 {
 644 }
 645
 646 static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
 647 {
 648 }
 649
 650 static inline void mem_cgroup_migrate(struct page *old, struct page *new)
 651 {
 652 }
 653
 654 static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
 655                                 struct mem_cgroup *memcg)
 656 {
 657         return node_lruvec(pgdat);
 658 }
 659
 660 static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
 661                                                     struct pglist_data *pgdat)
 662 {
 663         return &pgdat->lruvec;
 664 }
 665
 666 static inline bool mm_match_cgroup(struct mm_struct *mm,
 667                 struct mem_cgroup *memcg)
 668 {
 669         return true;
 670 }
 671
 672 static inline bool task_in_mem_cgroup(struct task_struct *task,
 673                                       const struct mem_cgroup *memcg)
 674 {
 675         return true;
 676 }
 677
 678 static inline struct mem_cgroup *
 679 mem_cgroup_iter(struct mem_cgroup *root,
 680                 struct mem_cgroup *prev,
 681                 struct mem_cgroup_reclaim_cookie *reclaim)
 682 {
 683         return NULL;
 684 }
 685
 686 static inline void mem_cgroup_iter_break(struct mem_cgroup *root,
 687                                          struct mem_cgroup *prev)
 688 {
 689 }
 690
 691 static inline int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
 692                 int (*fn)(struct task_struct *, void *), void *arg)
 693 {
 694         return 0;
 695 }
 696
 697 static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
 698 {
 699         return 0;
 700 }
 701
 702 static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
 703 {
 704         WARN_ON_ONCE(id);
 705         /* XXX: This should always return root_mem_cgroup */
 706         return NULL;
 707 }
 708
 709 static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
 710 {
 711         return true;
 712 }
 713
 714 static inline unsigned long
 715 mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
 716 {
 717         return 0;
 718 }
 719 static inline
 720 unsigned long mem_cgroup_get_zone_lru_size(struct lruvec *lruvec,
 721                 enum lru_list lru, int zone_idx)
 722 {
 723         return 0;
 724 }
 725
 726 static inline unsigned long
 727 mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg,
 728                              int nid, unsigned int lru_mask)
 729 {
 730         return 0;
 731 }
 732
 733 static inline unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg)
 734 {
 735         return 0;
 736 }
 737
 738 static inline void
 739 mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
 740 {
 741 }
 742
 743 static inline void lock_page_memcg(struct page *page)
 744 {
 745 }
 746
 747 static inline void unlock_page_memcg(struct page *page)
 748 {
 749 }
 750
 751 static inline void mem_cgroup_handle_over_high(void)
 752 {
 753 }
 754
 755 static inline void mem_cgroup_oom_enable(void)
 756 {
 757 }
 758
 759 static inline void mem_cgroup_oom_disable(void)
 760 {
 761 }
 762
 763 static inline bool task_in_memcg_oom(struct task_struct *p)
 764 {
 765         return false;
 766 }
 767
 768 static inline bool mem_cgroup_oom_synchronize(bool wait)
 769 {
 770         return false;
 771 }
 772
 773 static inline unsigned long mem_cgroup_read_stat(struct mem_cgroup *memcg,
 774                                                  enum mem_cgroup_stat_index idx)
 775 {
 776         return 0;
 777 }
 778
 779 static inline void mem_cgroup_update_stat(struct mem_cgroup *memcg,
 780                                    enum mem_cgroup_stat_index idx, int val)
 781 {
 782 }
 783
 784 static inline void mem_cgroup_inc_stat(struct mem_cgroup *memcg,
 785                                    enum mem_cgroup_stat_index idx)
 786 {
 787 }
 788
 789 static inline void mem_cgroup_dec_stat(struct mem_cgroup *memcg,
 790                                    enum mem_cgroup_stat_index idx)
 791 {
 792 }
 793
 794 static inline void mem_cgroup_update_page_stat(struct page *page,
 795                                                enum mem_cgroup_stat_index idx,
 796                                                int nr)
 797 {
 798 }
 799
 800 static inline void mem_cgroup_inc_page_stat(struct page *page,
 801                                             enum mem_cgroup_stat_index idx)
 802 {
 803 }
 804
 805 static inline void mem_cgroup_dec_page_stat(struct page *page,
 806                                             enum mem_cgroup_stat_index idx)
 807 {
 808 }
 809
 810 static inline
 811 unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
 812                                             gfp_t gfp_mask,
 813                                             unsigned long *total_scanned)
 814 {
 815         return 0;
 816 }
 817
 818 static inline void mem_cgroup_split_huge_fixup(struct page *head)
 819 {
 820 }
 821
 822 static inline
 823 void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
 824 {
 825 }
 826 #endif /* CONFIG_MEMCG */
 827
 828 #ifdef CONFIG_CGROUP_WRITEBACK
 829
 830 struct list_head *mem_cgroup_cgwb_list(struct mem_cgroup *memcg);
 831 struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb);
 832 void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
 833                          unsigned long *pheadroom, unsigned long *pdirty,
 834                          unsigned long *pwriteback);
 835
 836 #else   /* CONFIG_CGROUP_WRITEBACK */
 837
 838 static inline struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb)
 839 {
 840         return NULL;
 841 }
 842
 843 static inline void mem_cgroup_wb_stats(struct bdi_writeback *wb,
 844                                        unsigned long *pfilepages,
 845                                        unsigned long *pheadroom,
 846                                        unsigned long *pdirty,
 847                                        unsigned long *pwriteback)
 848 {
 849 }
 850
 851 #endif  /* CONFIG_CGROUP_WRITEBACK */
 852
 853 struct sock;
 854 bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
 855 void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
 856 #ifdef CONFIG_MEMCG
 857 extern struct static_key_false memcg_sockets_enabled_key;
 858 #define mem_cgroup_sockets_enabled static_branch_unlikely(&memcg_sockets_enabled_key)
 859 void mem_cgroup_sk_alloc(struct sock *sk);
 860 void mem_cgroup_sk_free(struct sock *sk);
 861 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
 862 {
 863         if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_pressure)
 864                 return true;
 865         do {
 866                 if (time_before(jiffies, memcg->socket_pressure))
 867                         return true;
 868         } while ((memcg = parent_mem_cgroup(memcg)));
 869         return false;
 870 }
 871 #else
 872 #define mem_cgroup_sockets_enabled 0
 873 static inline void mem_cgroup_sk_alloc(struct sock *sk) { };
 874 static inline void mem_cgroup_sk_free(struct sock *sk) { };
 875 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
 876 {
 877         return false;
 878 }
 879 #endif
 880
 881 struct kmem_cache *memcg_kmem_get_cache(struct kmem_cache *cachep);
 882 void memcg_kmem_put_cache(struct kmem_cache *cachep);
 883 int memcg_kmem_charge_memcg(struct page *page, gfp_t gfp, int order,
 884                             struct mem_cgroup *memcg);
 885 int memcg_kmem_charge(struct page *page, gfp_t gfp, int order);
 886 void memcg_kmem_uncharge(struct page *page, int order);
 887
 888 #if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
 889 extern struct static_key_false memcg_kmem_enabled_key;
 890 extern struct workqueue_struct *memcg_kmem_cache_wq;
 891
 892 extern int memcg_nr_cache_ids;
 893 void memcg_get_cache_ids(void);
 894 void memcg_put_cache_ids(void);
 895
 896 /*
 897  * Helper macro to loop through all memcg-specific caches. Callers must still
 898  * check if the cache is valid (it is either valid or NULL).
 899  * the slab_mutex must be held when looping through those caches
 900  */
 901 #define for_each_memcg_cache_index(_idx)        \
 902         for ((_idx) = 0; (_idx) < memcg_nr_cache_ids; (_idx)++)
 903
 904 static inline bool memcg_kmem_enabled(void)
 905 {
 906         return static_branch_unlikely(&memcg_kmem_enabled_key);
 907 }
 908
 909 /*
 910  * helper for accessing a memcg's index. It will be used as an index in the
 911  * child cache array in kmem_cache, and also to derive its name. This function
 912  * will return -1 when this is not a kmem-limited memcg.
 913  */
 914 static inline int memcg_cache_id(struct mem_cgroup *memcg)
 915 {
 916         return memcg ? memcg->kmemcg_id : -1;
 917 }
 918
 919 /**
 920  * memcg_kmem_update_page_stat - update kmem page state statistics
 921  * @page: the page
 922  * @idx: page state item to account
 923  * @val: number of pages (positive or negative)
 924  */
 925 static inline void memcg_kmem_update_page_stat(struct page *page,
 926                                 enum mem_cgroup_stat_index idx, int val)
 927 {
 928         if (memcg_kmem_enabled() && page->mem_cgroup)
 929                 this_cpu_add(page->mem_cgroup->stat->count[idx], val);
 930 }
 931
 932 #else
 933 #define for_each_memcg_cache_index(_idx)        \
 934         for (; NULL; )
 935
 936 static inline bool memcg_kmem_enabled(void)
 937 {
 938         return false;
 939 }
 940
 941 static inline int memcg_cache_id(struct mem_cgroup *memcg)
 942 {
 943         return -1;
 944 }
 945
 946 static inline void memcg_get_cache_ids(void)
 947 {
 948 }
 949
 950 static inline void memcg_put_cache_ids(void)
 951 {
 952 }
 953
 954 static inline void memcg_kmem_update_page_stat(struct page *page,
 955                                 enum mem_cgroup_stat_index idx, int val)
 956 {
 957 }
 958 #endif /* CONFIG_MEMCG && !CONFIG_SLOB */
 959
 960 #endif /* _LINUX_MEMCONTROL_H */