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
  27 struct mem_cgroup;
  28 struct page_cgroup;
  29 struct page;
  30 struct mm_struct;
  31 struct kmem_cache;
  32
  33 /*
  34  * The corresponding mem_cgroup_stat_names is defined in mm/memcontrol.c,
  35  * These two lists should keep in accord with each other.
  36  */
  37 enum mem_cgroup_stat_index {
  38         /*
  39          * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
  40          */
  41         MEM_CGROUP_STAT_CACHE,          /* # of pages charged as cache */
  42         MEM_CGROUP_STAT_RSS,            /* # of pages charged as anon rss */
  43         MEM_CGROUP_STAT_RSS_HUGE,       /* # of pages charged as anon huge */
  44         MEM_CGROUP_STAT_FILE_MAPPED,    /* # of pages charged as file rss */
  45         MEM_CGROUP_STAT_WRITEBACK,      /* # of pages under writeback */
  46         MEM_CGROUP_STAT_SWAP,           /* # of pages, swapped out */
  47         MEM_CGROUP_STAT_NSTATS,
  48 };
  49
  50 struct mem_cgroup_reclaim_cookie {
  51         struct zone *zone;
  52         int priority;
  53         unsigned int generation;
  54 };
  55
  56 #ifdef CONFIG_MEMCG
  57 /*
  58  * All "charge" functions with gfp_mask should use GFP_KERNEL or
  59  * (gfp_mask & GFP_RECLAIM_MASK). In current implementatin, memcg doesn't
  60  * alloc memory but reclaims memory from all available zones. So, "where I want
  61  * memory from" bits of gfp_mask has no meaning. So any bits of that field is
  62  * available but adding a rule is better. charge functions' gfp_mask should
  63  * be set to GFP_KERNEL or gfp_mask & GFP_RECLAIM_MASK for avoiding ambiguous
  64  * codes.
  65  * (Of course, if memcg does memory allocation in future, GFP_KERNEL is sane.)
  66  */
  67
  68 extern int mem_cgroup_newpage_charge(struct page *page, struct mm_struct *mm,
  69                                 gfp_t gfp_mask);
  70 /* for swap handling */
  71 extern int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
  72                 struct page *page, gfp_t mask, struct mem_cgroup **memcgp);
  73 extern void mem_cgroup_commit_charge_swapin(struct page *page,
  74                                         struct mem_cgroup *memcg);
  75 extern void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg);
  76
  77 extern int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
  78                                         gfp_t gfp_mask);
  79
  80 struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *);
  81 struct lruvec *mem_cgroup_page_lruvec(struct page *, struct zone *);
  82
  83 /* For coalescing uncharge for reducing memcg' overhead*/
  84 extern void mem_cgroup_uncharge_start(void);
  85 extern void mem_cgroup_uncharge_end(void);
  86
  87 extern void mem_cgroup_uncharge_page(struct page *page);
  88 extern void mem_cgroup_uncharge_cache_page(struct page *page);
  89
  90 bool __mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg,
  91                                   struct mem_cgroup *memcg);
  92 bool task_in_mem_cgroup(struct task_struct *task,
  93                         const struct mem_cgroup *memcg);
  94
  95 extern struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page);
  96 extern struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
  97 extern struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm);
  98
  99 extern struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg);
 100 extern struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css);
 101
 102 static inline
 103 bool mm_match_cgroup(const struct mm_struct *mm, const struct mem_cgroup *memcg)
 104 {
 105         struct mem_cgroup *task_memcg;
 106         bool match;
 107
 108         rcu_read_lock();
 109         task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
 110         match = __mem_cgroup_same_or_subtree(memcg, task_memcg);
 111         rcu_read_unlock();
 112         return match;
 113 }
 114
 115 extern struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *memcg);
 116
 117 extern void
 118 mem_cgroup_prepare_migration(struct page *page, struct page *newpage,
 119                              struct mem_cgroup **memcgp);
 120 extern void mem_cgroup_end_migration(struct mem_cgroup *memcg,
 121         struct page *oldpage, struct page *newpage, bool migration_ok);
 122
 123 struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *,
 124                                    struct mem_cgroup *,
 125                                    struct mem_cgroup_reclaim_cookie *);
 126 void mem_cgroup_iter_break(struct mem_cgroup *, struct mem_cgroup *);
 127
 128 /*
 129  * For memory reclaim.
 130  */
 131 int mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec);
 132 int mem_cgroup_select_victim_node(struct mem_cgroup *memcg);
 133 unsigned long mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list);
 134 void mem_cgroup_update_lru_size(struct lruvec *, enum lru_list, int);
 135 extern void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
 136                                         struct task_struct *p);
 137 extern void mem_cgroup_replace_page_cache(struct page *oldpage,
 138                                         struct page *newpage);
 139
 140 /**
 141  * mem_cgroup_toggle_oom - toggle the memcg OOM killer for the current task
 142  * @new: true to enable, false to disable
 143  *
 144  * Toggle whether a failed memcg charge should invoke the OOM killer
 145  * or just return -ENOMEM.  Returns the previous toggle state.
 146  *
 147  * NOTE: Any path that enables the OOM killer before charging must
 148  *       call mem_cgroup_oom_synchronize() afterward to finalize the
 149  *       OOM handling and clean up.
 150  */
 151 static inline bool mem_cgroup_toggle_oom(bool new)
 152 {
 153         bool old;
 154
 155         old = current->memcg_oom.may_oom;
 156         current->memcg_oom.may_oom = new;
 157
 158         return old;
 159 }
 160
 161 static inline void mem_cgroup_enable_oom(void)
 162 {
 163         bool old = mem_cgroup_toggle_oom(true);
 164
 165         WARN_ON(old == true);
 166 }
 167
 168 static inline void mem_cgroup_disable_oom(void)
 169 {
 170         bool old = mem_cgroup_toggle_oom(false);
 171
 172         WARN_ON(old == false);
 173 }
 174
 175 static inline bool task_in_memcg_oom(struct task_struct *p)
 176 {
 177         return p->memcg_oom.in_memcg_oom;
 178 }
 179
 180 bool mem_cgroup_oom_synchronize(void);
 181
 182 #ifdef CONFIG_MEMCG_SWAP
 183 extern int do_swap_account;
 184 #endif
 185
 186 static inline bool mem_cgroup_disabled(void)
 187 {
 188         if (mem_cgroup_subsys.disabled)
 189                 return true;
 190         return false;
 191 }
 192
 193 void __mem_cgroup_begin_update_page_stat(struct page *page, bool *locked,
 194                                          unsigned long *flags);
 195
 196 extern atomic_t memcg_moving;
 197
 198 static inline void mem_cgroup_begin_update_page_stat(struct page *page,
 199                                         bool *locked, unsigned long *flags)
 200 {
 201         if (mem_cgroup_disabled())
 202                 return;
 203         rcu_read_lock();
 204         *locked = false;
 205         if (atomic_read(&memcg_moving))
 206                 __mem_cgroup_begin_update_page_stat(page, locked, flags);
 207 }
 208
 209 void __mem_cgroup_end_update_page_stat(struct page *page,
 210                                 unsigned long *flags);
 211 static inline void mem_cgroup_end_update_page_stat(struct page *page,
 212                                         bool *locked, unsigned long *flags)
 213 {
 214         if (mem_cgroup_disabled())
 215                 return;
 216         if (*locked)
 217                 __mem_cgroup_end_update_page_stat(page, flags);
 218         rcu_read_unlock();
 219 }
 220
 221 void mem_cgroup_update_page_stat(struct page *page,
 222                                  enum mem_cgroup_stat_index idx,
 223                                  int val);
 224
 225 static inline void mem_cgroup_inc_page_stat(struct page *page,
 226                                             enum mem_cgroup_stat_index idx)
 227 {
 228         mem_cgroup_update_page_stat(page, idx, 1);
 229 }
 230
 231 static inline void mem_cgroup_dec_page_stat(struct page *page,
 232                                             enum mem_cgroup_stat_index idx)
 233 {
 234         mem_cgroup_update_page_stat(page, idx, -1);
 235 }
 236
 237 bool mem_cgroup_soft_reclaim_eligible(struct mem_cgroup *memcg,
 238                 struct mem_cgroup *root);
 239
 240 void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx);
 241 static inline void mem_cgroup_count_vm_event(struct mm_struct *mm,
 242                                              enum vm_event_item idx)
 243 {
 244         if (mem_cgroup_disabled())
 245                 return;
 246         __mem_cgroup_count_vm_event(mm, idx);
 247 }
 248 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 249 void mem_cgroup_split_huge_fixup(struct page *head);
 250 #endif
 251
 252 #ifdef CONFIG_DEBUG_VM
 253 bool mem_cgroup_bad_page_check(struct page *page);
 254 void mem_cgroup_print_bad_page(struct page *page);
 255 #endif
 256 #else /* CONFIG_MEMCG */
 257 struct mem_cgroup;
 258
 259 static inline int mem_cgroup_newpage_charge(struct page *page,
 260                                         struct mm_struct *mm, gfp_t gfp_mask)
 261 {
 262         return 0;
 263 }
 264
 265 static inline int mem_cgroup_cache_charge(struct page *page,
 266                                         struct mm_struct *mm, gfp_t gfp_mask)
 267 {
 268         return 0;
 269 }
 270
 271 static inline int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
 272                 struct page *page, gfp_t gfp_mask, struct mem_cgroup **memcgp)
 273 {
 274         return 0;
 275 }
 276
 277 static inline void mem_cgroup_commit_charge_swapin(struct page *page,
 278                                           struct mem_cgroup *memcg)
 279 {
 280 }
 281
 282 static inline void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg)
 283 {
 284 }
 285
 286 static inline void mem_cgroup_uncharge_start(void)
 287 {
 288 }
 289
 290 static inline void mem_cgroup_uncharge_end(void)
 291 {
 292 }
 293
 294 static inline void mem_cgroup_uncharge_page(struct page *page)
 295 {
 296 }
 297
 298 static inline void mem_cgroup_uncharge_cache_page(struct page *page)
 299 {
 300 }
 301
 302 static inline struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone,
 303                                                     struct mem_cgroup *memcg)
 304 {
 305         return &zone->lruvec;
 306 }
 307
 308 static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
 309                                                     struct zone *zone)
 310 {
 311         return &zone->lruvec;
 312 }
 313
 314 static inline struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
 315 {
 316         return NULL;
 317 }
 318
 319 static inline struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm)
 320 {
 321         return NULL;
 322 }
 323
 324 static inline bool mm_match_cgroup(struct mm_struct *mm,
 325                 struct mem_cgroup *memcg)
 326 {
 327         return true;
 328 }
 329
 330 static inline bool task_in_mem_cgroup(struct task_struct *task,
 331                                       const struct mem_cgroup *memcg)
 332 {
 333         return true;
 334 }
 335
 336 static inline struct cgroup_subsys_state
 337                 *mem_cgroup_css(struct mem_cgroup *memcg)
 338 {
 339         return NULL;
 340 }
 341
 342 static inline void
 343 mem_cgroup_prepare_migration(struct page *page, struct page *newpage,
 344                              struct mem_cgroup **memcgp)
 345 {
 346 }
 347
 348 static inline void mem_cgroup_end_migration(struct mem_cgroup *memcg,
 349                 struct page *oldpage, struct page *newpage, bool migration_ok)
 350 {
 351 }
 352
 353 static inline struct mem_cgroup *
 354 mem_cgroup_iter(struct mem_cgroup *root,
 355                 struct mem_cgroup *prev,
 356                 struct mem_cgroup_reclaim_cookie *reclaim)
 357 {
 358         return NULL;
 359 }
 360
 361 static inline void mem_cgroup_iter_break(struct mem_cgroup *root,
 362                                          struct mem_cgroup *prev)
 363 {
 364 }
 365
 366 static inline bool mem_cgroup_disabled(void)
 367 {
 368         return true;
 369 }
 370
 371 static inline int
 372 mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec)
 373 {
 374         return 1;
 375 }
 376
 377 static inline unsigned long
 378 mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
 379 {
 380         return 0;
 381 }
 382
 383 static inline void
 384 mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
 385                               int increment)
 386 {
 387 }
 388
 389 static inline void
 390 mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
 391 {
 392 }
 393
 394 static inline void mem_cgroup_begin_update_page_stat(struct page *page,
 395                                         bool *locked, unsigned long *flags)
 396 {
 397 }
 398
 399 static inline void mem_cgroup_end_update_page_stat(struct page *page,
 400                                         bool *locked, unsigned long *flags)
 401 {
 402 }
 403
 404 static inline bool mem_cgroup_toggle_oom(bool new)
 405 {
 406         return false;
 407 }
 408
 409 static inline void mem_cgroup_enable_oom(void)
 410 {
 411 }
 412
 413 static inline void mem_cgroup_disable_oom(void)
 414 {
 415 }
 416
 417 static inline bool task_in_memcg_oom(struct task_struct *p)
 418 {
 419         return false;
 420 }
 421
 422 static inline bool mem_cgroup_oom_synchronize(void)
 423 {
 424         return false;
 425 }
 426
 427 static inline void mem_cgroup_inc_page_stat(struct page *page,
 428                                             enum mem_cgroup_stat_index idx)
 429 {
 430 }
 431
 432 static inline void mem_cgroup_dec_page_stat(struct page *page,
 433                                             enum mem_cgroup_stat_index idx)
 434 {
 435 }
 436
 437 static inline
 438 bool mem_cgroup_soft_reclaim_eligible(struct mem_cgroup *memcg,
 439                 struct mem_cgroup *root)
 440 {
 441         return false;
 442 }
 443
 444 static inline void mem_cgroup_split_huge_fixup(struct page *head)
 445 {
 446 }
 447
 448 static inline
 449 void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
 450 {
 451 }
 452 static inline void mem_cgroup_replace_page_cache(struct page *oldpage,
 453                                 struct page *newpage)
 454 {
 455 }
 456 #endif /* CONFIG_MEMCG */
 457
 458 #if !defined(CONFIG_MEMCG) || !defined(CONFIG_DEBUG_VM)
 459 static inline bool
 460 mem_cgroup_bad_page_check(struct page *page)
 461 {
 462         return false;
 463 }
 464
 465 static inline void
 466 mem_cgroup_print_bad_page(struct page *page)
 467 {
 468 }
 469 #endif
 470
 471 enum {
 472         UNDER_LIMIT,
 473         SOFT_LIMIT,
 474         OVER_LIMIT,
 475 };
 476
 477 struct sock;
 478 #if defined(CONFIG_INET) && defined(CONFIG_MEMCG_KMEM)
 479 void sock_update_memcg(struct sock *sk);
 480 void sock_release_memcg(struct sock *sk);
 481 #else
 482 static inline void sock_update_memcg(struct sock *sk)
 483 {
 484 }
 485 static inline void sock_release_memcg(struct sock *sk)
 486 {
 487 }
 488 #endif /* CONFIG_INET && CONFIG_MEMCG_KMEM */
 489
 490 #ifdef CONFIG_MEMCG_KMEM
 491 extern struct static_key memcg_kmem_enabled_key;
 492
 493 extern int memcg_limited_groups_array_size;
 494
 495 /*
 496  * Helper macro to loop through all memcg-specific caches. Callers must still
 497  * check if the cache is valid (it is either valid or NULL).
 498  * the slab_mutex must be held when looping through those caches
 499  */
 500 #define for_each_memcg_cache_index(_idx)        \
 501         for ((_idx) = 0; (_idx) < memcg_limited_groups_array_size; (_idx)++)
 502
 503 static inline bool memcg_kmem_enabled(void)
 504 {
 505         return static_key_false(&memcg_kmem_enabled_key);
 506 }
 507
 508 /*
 509  * In general, we'll do everything in our power to not incur in any overhead
 510  * for non-memcg users for the kmem functions. Not even a function call, if we
 511  * can avoid it.
 512  *
 513  * Therefore, we'll inline all those functions so that in the best case, we'll
 514  * see that kmemcg is off for everybody and proceed quickly.  If it is on,
 515  * we'll still do most of the flag checking inline. We check a lot of
 516  * conditions, but because they are pretty simple, they are expected to be
 517  * fast.
 518  */
 519 bool __memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **memcg,
 520                                         int order);
 521 void __memcg_kmem_commit_charge(struct page *page,
 522                                        struct mem_cgroup *memcg, int order);
 523 void __memcg_kmem_uncharge_pages(struct page *page, int order);
 524
 525 int memcg_cache_id(struct mem_cgroup *memcg);
 526 int memcg_register_cache(struct mem_cgroup *memcg, struct kmem_cache *s,
 527                          struct kmem_cache *root_cache);
 528 void memcg_release_cache(struct kmem_cache *cachep);
 529 void memcg_cache_list_add(struct mem_cgroup *memcg, struct kmem_cache *cachep);
 530
 531 int memcg_update_cache_size(struct kmem_cache *s, int num_groups);
 532 void memcg_update_array_size(int num_groups);
 533
 534 struct kmem_cache *
 535 __memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp);
 536
 537 void mem_cgroup_destroy_cache(struct kmem_cache *cachep);
 538 void kmem_cache_destroy_memcg_children(struct kmem_cache *s);
 539
 540 /**
 541  * memcg_kmem_newpage_charge: verify if a new kmem allocation is allowed.
 542  * @gfp: the gfp allocation flags.
 543  * @memcg: a pointer to the memcg this was charged against.
 544  * @order: allocation order.
 545  *
 546  * returns true if the memcg where the current task belongs can hold this
 547  * allocation.
 548  *
 549  * We return true automatically if this allocation is not to be accounted to
 550  * any memcg.
 551  */
 552 static inline bool
 553 memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **memcg, int order)
 554 {
 555         if (!memcg_kmem_enabled())
 556                 return true;
 557
 558         /*
 559          * __GFP_NOFAIL allocations will move on even if charging is not
 560          * possible. Therefore we don't even try, and have this allocation
 561          * unaccounted. We could in theory charge it with
 562          * res_counter_charge_nofail, but we hope those allocations are rare,
 563          * and won't be worth the trouble.
 564          */
 565         if (!(gfp & __GFP_KMEMCG) || (gfp & __GFP_NOFAIL))
 566                 return true;
 567         if (in_interrupt() || (!current->mm) || (current->flags & PF_KTHREAD))
 568                 return true;
 569
 570         /* If the test is dying, just let it go. */
 571         if (unlikely(fatal_signal_pending(current)))
 572                 return true;
 573
 574         return __memcg_kmem_newpage_charge(gfp, memcg, order);
 575 }
 576
 577 /**
 578  * memcg_kmem_uncharge_pages: uncharge pages from memcg
 579  * @page: pointer to struct page being freed
 580  * @order: allocation order.
 581  *
 582  * there is no need to specify memcg here, since it is embedded in page_cgroup
 583  */
 584 static inline void
 585 memcg_kmem_uncharge_pages(struct page *page, int order)
 586 {
 587         if (memcg_kmem_enabled())
 588                 __memcg_kmem_uncharge_pages(page, order);
 589 }
 590
 591 /**
 592  * memcg_kmem_commit_charge: embeds correct memcg in a page
 593  * @page: pointer to struct page recently allocated
 594  * @memcg: the memcg structure we charged against
 595  * @order: allocation order.
 596  *
 597  * Needs to be called after memcg_kmem_newpage_charge, regardless of success or
 598  * failure of the allocation. if @page is NULL, this function will revert the
 599  * charges. Otherwise, it will commit the memcg given by @memcg to the
 600  * corresponding page_cgroup.
 601  */
 602 static inline void
 603 memcg_kmem_commit_charge(struct page *page, struct mem_cgroup *memcg, int order)
 604 {
 605         if (memcg_kmem_enabled() && memcg)
 606                 __memcg_kmem_commit_charge(page, memcg, order);
 607 }
 608
 609 /**
 610  * memcg_kmem_get_cache: selects the correct per-memcg cache for allocation
 611  * @cachep: the original global kmem cache
 612  * @gfp: allocation flags.
 613  *
 614  * This function assumes that the task allocating, which determines the memcg
 615  * in the page allocator, belongs to the same cgroup throughout the whole
 616  * process.  Misacounting can happen if the task calls memcg_kmem_get_cache()
 617  * while belonging to a cgroup, and later on changes. This is considered
 618  * acceptable, and should only happen upon task migration.
 619  *
 620  * Before the cache is created by the memcg core, there is also a possible
 621  * imbalance: the task belongs to a memcg, but the cache being allocated from
 622  * is the global cache, since the child cache is not yet guaranteed to be
 623  * ready. This case is also fine, since in this case the GFP_KMEMCG will not be
 624  * passed and the page allocator will not attempt any cgroup accounting.
 625  */
 626 static __always_inline struct kmem_cache *
 627 memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp)
 628 {
 629         if (!memcg_kmem_enabled())
 630                 return cachep;
 631         if (gfp & __GFP_NOFAIL)
 632                 return cachep;
 633         if (in_interrupt() || (!current->mm) || (current->flags & PF_KTHREAD))
 634                 return cachep;
 635         if (unlikely(fatal_signal_pending(current)))
 636                 return cachep;
 637
 638         return __memcg_kmem_get_cache(cachep, gfp);
 639 }
 640 #else
 641 #define for_each_memcg_cache_index(_idx)        \
 642         for (; NULL; )
 643
 644 static inline bool memcg_kmem_enabled(void)
 645 {
 646         return false;
 647 }
 648
 649 static inline bool
 650 memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **memcg, int order)
 651 {
 652         return true;
 653 }
 654
 655 static inline void memcg_kmem_uncharge_pages(struct page *page, int order)
 656 {
 657 }
 658
 659 static inline void
 660 memcg_kmem_commit_charge(struct page *page, struct mem_cgroup *memcg, int order)
 661 {
 662 }
 663
 664 static inline int memcg_cache_id(struct mem_cgroup *memcg)
 665 {
 666         return -1;
 667 }
 668
 669 static inline int
 670 memcg_register_cache(struct mem_cgroup *memcg, struct kmem_cache *s,
 671                      struct kmem_cache *root_cache)
 672 {
 673         return 0;
 674 }
 675
 676 static inline void memcg_release_cache(struct kmem_cache *cachep)
 677 {
 678 }
 679
 680 static inline void memcg_cache_list_add(struct mem_cgroup *memcg,
 681                                         struct kmem_cache *s)
 682 {
 683 }
 684
 685 static inline struct kmem_cache *
 686 memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp)
 687 {
 688         return cachep;
 689 }
 690
 691 static inline void kmem_cache_destroy_memcg_children(struct kmem_cache *s)
 692 {
 693 }
 694 #endif /* CONFIG_MEMCG_KMEM */
 695 #endif /* _LINUX_MEMCONTROL_H */
 696