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;
  29 struct mm_struct;
  30 struct kmem_cache;
  31
  32 /*
  33  * The corresponding mem_cgroup_stat_names is defined in mm/memcontrol.c,
  34  * These two lists should keep in accord with each other.
  35  */
  36 enum mem_cgroup_stat_index {
  37         /*
  38          * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
  39          */
  40         MEM_CGROUP_STAT_CACHE,          /* # of pages charged as cache */
  41         MEM_CGROUP_STAT_RSS,            /* # of pages charged as anon rss */
  42         MEM_CGROUP_STAT_RSS_HUGE,       /* # of pages charged as anon huge */
  43         MEM_CGROUP_STAT_FILE_MAPPED,    /* # of pages charged as file rss */
  44         MEM_CGROUP_STAT_WRITEBACK,      /* # of pages under writeback */
  45         MEM_CGROUP_STAT_SWAP,           /* # of pages, swapped out */
  46         MEM_CGROUP_STAT_NSTATS,
  47 };
  48
  49 struct mem_cgroup_reclaim_cookie {
  50         struct zone *zone;
  51         int priority;
  52         unsigned int generation;
  53 };
  54
  55 enum mem_cgroup_events_index {
  56         MEM_CGROUP_EVENTS_PGPGIN,       /* # of pages paged in */
  57         MEM_CGROUP_EVENTS_PGPGOUT,      /* # of pages paged out */
  58         MEM_CGROUP_EVENTS_PGFAULT,      /* # of page-faults */
  59         MEM_CGROUP_EVENTS_PGMAJFAULT,   /* # of major page-faults */
  60         MEM_CGROUP_EVENTS_NSTATS,
  61         /* default hierarchy events */
  62         MEMCG_LOW = MEM_CGROUP_EVENTS_NSTATS,
  63         MEMCG_HIGH,
  64         MEMCG_MAX,
  65         MEMCG_OOM,
  66         MEMCG_NR_EVENTS,
  67 };
  68
  69 #ifdef CONFIG_MEMCG
  70 void mem_cgroup_events(struct mem_cgroup *memcg,
  71                        enum mem_cgroup_events_index idx,
  72                        unsigned int nr);
  73
  74 bool mem_cgroup_low(struct mem_cgroup *root, struct mem_cgroup *memcg);
  75
  76 int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
  77                           gfp_t gfp_mask, struct mem_cgroup **memcgp);
  78 void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
  79                               bool lrucare);
  80 void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg);
  81 void mem_cgroup_uncharge(struct page *page);
  82 void mem_cgroup_uncharge_list(struct list_head *page_list);
  83
  84 void mem_cgroup_migrate(struct page *oldpage, struct page *newpage,
  85                         bool lrucare);
  86
  87 struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *);
  88 struct lruvec *mem_cgroup_page_lruvec(struct page *, struct zone *);
  89
  90 bool mem_cgroup_is_descendant(struct mem_cgroup *memcg,
  91                               struct mem_cgroup *root);
  92 bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg);
  93
  94 extern struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page);
  95 extern struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
  96
  97 extern struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg);
  98 extern struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css);
  99
 100 static inline bool mm_match_cgroup(struct mm_struct *mm,
 101                                    struct mem_cgroup *memcg)
 102 {
 103         struct mem_cgroup *task_memcg;
 104         bool match = false;
 105
 106         rcu_read_lock();
 107         task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
 108         if (task_memcg)
 109                 match = mem_cgroup_is_descendant(task_memcg, memcg);
 110         rcu_read_unlock();
 111         return match;
 112 }
 113
 114 extern struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *memcg);
 115
 116 struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *,
 117                                    struct mem_cgroup *,
 118                                    struct mem_cgroup_reclaim_cookie *);
 119 void mem_cgroup_iter_break(struct mem_cgroup *, struct mem_cgroup *);
 120
 121 /*
 122  * For memory reclaim.
 123  */
 124 int mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec);
 125 bool mem_cgroup_lruvec_online(struct lruvec *lruvec);
 126 int mem_cgroup_select_victim_node(struct mem_cgroup *memcg);
 127 unsigned long mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list);
 128 void mem_cgroup_update_lru_size(struct lruvec *, enum lru_list, int);
 129 extern void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
 130                                         struct task_struct *p);
 131
 132 static inline void mem_cgroup_oom_enable(void)
 133 {
 134         WARN_ON(current->memcg_oom.may_oom);
 135         current->memcg_oom.may_oom = 1;
 136 }
 137
 138 static inline void mem_cgroup_oom_disable(void)
 139 {
 140         WARN_ON(!current->memcg_oom.may_oom);
 141         current->memcg_oom.may_oom = 0;
 142 }
 143
 144 static inline bool task_in_memcg_oom(struct task_struct *p)
 145 {
 146         return p->memcg_oom.memcg;
 147 }
 148
 149 bool mem_cgroup_oom_synchronize(bool wait);
 150
 151 #ifdef CONFIG_MEMCG_SWAP
 152 extern int do_swap_account;
 153 #endif
 154
 155 static inline bool mem_cgroup_disabled(void)
 156 {
 157         if (memory_cgrp_subsys.disabled)
 158                 return true;
 159         return false;
 160 }
 161
 162 struct mem_cgroup *mem_cgroup_begin_page_stat(struct page *page);
 163 void mem_cgroup_update_page_stat(struct mem_cgroup *memcg,
 164                                  enum mem_cgroup_stat_index idx, int val);
 165 void mem_cgroup_end_page_stat(struct mem_cgroup *memcg);
 166
 167 static inline void mem_cgroup_inc_page_stat(struct mem_cgroup *memcg,
 168                                             enum mem_cgroup_stat_index idx)
 169 {
 170         mem_cgroup_update_page_stat(memcg, idx, 1);
 171 }
 172
 173 static inline void mem_cgroup_dec_page_stat(struct mem_cgroup *memcg,
 174                                             enum mem_cgroup_stat_index idx)
 175 {
 176         mem_cgroup_update_page_stat(memcg, idx, -1);
 177 }
 178
 179 unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
 180                                                 gfp_t gfp_mask,
 181                                                 unsigned long *total_scanned);
 182
 183 void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx);
 184 static inline void mem_cgroup_count_vm_event(struct mm_struct *mm,
 185                                              enum vm_event_item idx)
 186 {
 187         if (mem_cgroup_disabled())
 188                 return;
 189         __mem_cgroup_count_vm_event(mm, idx);
 190 }
 191 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 192 void mem_cgroup_split_huge_fixup(struct page *head);
 193 #endif
 194
 195 #else /* CONFIG_MEMCG */
 196 struct mem_cgroup;
 197
 198 static inline void mem_cgroup_events(struct mem_cgroup *memcg,
 199                                      enum mem_cgroup_events_index idx,
 200                                      unsigned int nr)
 201 {
 202 }
 203
 204 static inline bool mem_cgroup_low(struct mem_cgroup *root,
 205                                   struct mem_cgroup *memcg)
 206 {
 207         return false;
 208 }
 209
 210 static inline int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
 211                                         gfp_t gfp_mask,
 212                                         struct mem_cgroup **memcgp)
 213 {
 214         *memcgp = NULL;
 215         return 0;
 216 }
 217
 218 static inline void mem_cgroup_commit_charge(struct page *page,
 219                                             struct mem_cgroup *memcg,
 220                                             bool lrucare)
 221 {
 222 }
 223
 224 static inline void mem_cgroup_cancel_charge(struct page *page,
 225                                             struct mem_cgroup *memcg)
 226 {
 227 }
 228
 229 static inline void mem_cgroup_uncharge(struct page *page)
 230 {
 231 }
 232
 233 static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
 234 {
 235 }
 236
 237 static inline void mem_cgroup_migrate(struct page *oldpage,
 238                                       struct page *newpage,
 239                                       bool lrucare)
 240 {
 241 }
 242
 243 static inline struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone,
 244                                                     struct mem_cgroup *memcg)
 245 {
 246         return &zone->lruvec;
 247 }
 248
 249 static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
 250                                                     struct zone *zone)
 251 {
 252         return &zone->lruvec;
 253 }
 254
 255 static inline struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
 256 {
 257         return NULL;
 258 }
 259
 260 static inline bool mm_match_cgroup(struct mm_struct *mm,
 261                 struct mem_cgroup *memcg)
 262 {
 263         return true;
 264 }
 265
 266 static inline bool task_in_mem_cgroup(struct task_struct *task,
 267                                       const struct mem_cgroup *memcg)
 268 {
 269         return true;
 270 }
 271
 272 static inline struct cgroup_subsys_state
 273                 *mem_cgroup_css(struct mem_cgroup *memcg)
 274 {
 275         return NULL;
 276 }
 277
 278 static inline struct mem_cgroup *
 279 mem_cgroup_iter(struct mem_cgroup *root,
 280                 struct mem_cgroup *prev,
 281                 struct mem_cgroup_reclaim_cookie *reclaim)
 282 {
 283         return NULL;
 284 }
 285
 286 static inline void mem_cgroup_iter_break(struct mem_cgroup *root,
 287                                          struct mem_cgroup *prev)
 288 {
 289 }
 290
 291 static inline bool mem_cgroup_disabled(void)
 292 {
 293         return true;
 294 }
 295
 296 static inline int
 297 mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec)
 298 {
 299         return 1;
 300 }
 301
 302 static inline bool mem_cgroup_lruvec_online(struct lruvec *lruvec)
 303 {
 304         return true;
 305 }
 306
 307 static inline unsigned long
 308 mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
 309 {
 310         return 0;
 311 }
 312
 313 static inline void
 314 mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
 315                               int increment)
 316 {
 317 }
 318
 319 static inline void
 320 mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
 321 {
 322 }
 323
 324 static inline struct mem_cgroup *mem_cgroup_begin_page_stat(struct page *page)
 325 {
 326         return NULL;
 327 }
 328
 329 static inline void mem_cgroup_end_page_stat(struct mem_cgroup *memcg)
 330 {
 331 }
 332
 333 static inline void mem_cgroup_oom_enable(void)
 334 {
 335 }
 336
 337 static inline void mem_cgroup_oom_disable(void)
 338 {
 339 }
 340
 341 static inline bool task_in_memcg_oom(struct task_struct *p)
 342 {
 343         return false;
 344 }
 345
 346 static inline bool mem_cgroup_oom_synchronize(bool wait)
 347 {
 348         return false;
 349 }
 350
 351 static inline void mem_cgroup_inc_page_stat(struct mem_cgroup *memcg,
 352                                             enum mem_cgroup_stat_index idx)
 353 {
 354 }
 355
 356 static inline void mem_cgroup_dec_page_stat(struct mem_cgroup *memcg,
 357                                             enum mem_cgroup_stat_index idx)
 358 {
 359 }
 360
 361 static inline
 362 unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
 363                                             gfp_t gfp_mask,
 364                                             unsigned long *total_scanned)
 365 {
 366         return 0;
 367 }
 368
 369 static inline void mem_cgroup_split_huge_fixup(struct page *head)
 370 {
 371 }
 372
 373 static inline
 374 void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
 375 {
 376 }
 377 #endif /* CONFIG_MEMCG */
 378
 379 enum {
 380         UNDER_LIMIT,
 381         SOFT_LIMIT,
 382         OVER_LIMIT,
 383 };
 384
 385 struct sock;
 386 #if defined(CONFIG_INET) && defined(CONFIG_MEMCG_KMEM)
 387 void sock_update_memcg(struct sock *sk);
 388 void sock_release_memcg(struct sock *sk);
 389 #else
 390 static inline void sock_update_memcg(struct sock *sk)
 391 {
 392 }
 393 static inline void sock_release_memcg(struct sock *sk)
 394 {
 395 }
 396 #endif /* CONFIG_INET && CONFIG_MEMCG_KMEM */
 397
 398 #ifdef CONFIG_MEMCG_KMEM
 399 extern struct static_key memcg_kmem_enabled_key;
 400
 401 extern int memcg_nr_cache_ids;
 402 extern void memcg_get_cache_ids(void);
 403 extern void memcg_put_cache_ids(void);
 404
 405 /*
 406  * Helper macro to loop through all memcg-specific caches. Callers must still
 407  * check if the cache is valid (it is either valid or NULL).
 408  * the slab_mutex must be held when looping through those caches
 409  */
 410 #define for_each_memcg_cache_index(_idx)        \
 411         for ((_idx) = 0; (_idx) < memcg_nr_cache_ids; (_idx)++)
 412
 413 static inline bool memcg_kmem_enabled(void)
 414 {
 415         return static_key_false(&memcg_kmem_enabled_key);
 416 }
 417
 418 bool memcg_kmem_is_active(struct mem_cgroup *memcg);
 419
 420 /*
 421  * In general, we'll do everything in our power to not incur in any overhead
 422  * for non-memcg users for the kmem functions. Not even a function call, if we
 423  * can avoid it.
 424  *
 425  * Therefore, we'll inline all those functions so that in the best case, we'll
 426  * see that kmemcg is off for everybody and proceed quickly.  If it is on,
 427  * we'll still do most of the flag checking inline. We check a lot of
 428  * conditions, but because they are pretty simple, they are expected to be
 429  * fast.
 430  */
 431 bool __memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **memcg,
 432                                         int order);
 433 void __memcg_kmem_commit_charge(struct page *page,
 434                                        struct mem_cgroup *memcg, int order);
 435 void __memcg_kmem_uncharge_pages(struct page *page, int order);
 436
 437 int memcg_cache_id(struct mem_cgroup *memcg);
 438
 439 struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep);
 440 void __memcg_kmem_put_cache(struct kmem_cache *cachep);
 441
 442 struct mem_cgroup *__mem_cgroup_from_kmem(void *ptr);
 443
 444 int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp,
 445                       unsigned long nr_pages);
 446 void memcg_uncharge_kmem(struct mem_cgroup *memcg, unsigned long nr_pages);
 447
 448 /**
 449  * memcg_kmem_newpage_charge: verify if a new kmem allocation is allowed.
 450  * @gfp: the gfp allocation flags.
 451  * @memcg: a pointer to the memcg this was charged against.
 452  * @order: allocation order.
 453  *
 454  * returns true if the memcg where the current task belongs can hold this
 455  * allocation.
 456  *
 457  * We return true automatically if this allocation is not to be accounted to
 458  * any memcg.
 459  */
 460 static inline bool
 461 memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **memcg, int order)
 462 {
 463         if (!memcg_kmem_enabled())
 464                 return true;
 465
 466         if (gfp & __GFP_NOACCOUNT)
 467                 return true;
 468         /*
 469          * __GFP_NOFAIL allocations will move on even if charging is not
 470          * possible. Therefore we don't even try, and have this allocation
 471          * unaccounted. We could in theory charge it forcibly, but we hope
 472          * those allocations are rare, and won't be worth the trouble.
 473          */
 474         if (gfp & __GFP_NOFAIL)
 475                 return true;
 476         if (in_interrupt() || (!current->mm) || (current->flags & PF_KTHREAD))
 477                 return true;
 478
 479         /* If the test is dying, just let it go. */
 480         if (unlikely(fatal_signal_pending(current)))
 481                 return true;
 482
 483         return __memcg_kmem_newpage_charge(gfp, memcg, order);
 484 }
 485
 486 /**
 487  * memcg_kmem_uncharge_pages: uncharge pages from memcg
 488  * @page: pointer to struct page being freed
 489  * @order: allocation order.
 490  */
 491 static inline void
 492 memcg_kmem_uncharge_pages(struct page *page, int order)
 493 {
 494         if (memcg_kmem_enabled())
 495                 __memcg_kmem_uncharge_pages(page, order);
 496 }
 497
 498 /**
 499  * memcg_kmem_commit_charge: embeds correct memcg in a page
 500  * @page: pointer to struct page recently allocated
 501  * @memcg: the memcg structure we charged against
 502  * @order: allocation order.
 503  *
 504  * Needs to be called after memcg_kmem_newpage_charge, regardless of success or
 505  * failure of the allocation. if @page is NULL, this function will revert the
 506  * charges. Otherwise, it will commit @page to @memcg.
 507  */
 508 static inline void
 509 memcg_kmem_commit_charge(struct page *page, struct mem_cgroup *memcg, int order)
 510 {
 511         if (memcg_kmem_enabled() && memcg)
 512                 __memcg_kmem_commit_charge(page, memcg, order);
 513 }
 514
 515 /**
 516  * memcg_kmem_get_cache: selects the correct per-memcg cache for allocation
 517  * @cachep: the original global kmem cache
 518  * @gfp: allocation flags.
 519  *
 520  * All memory allocated from a per-memcg cache is charged to the owner memcg.
 521  */
 522 static __always_inline struct kmem_cache *
 523 memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp)
 524 {
 525         if (!memcg_kmem_enabled())
 526                 return cachep;
 527         if (gfp & __GFP_NOACCOUNT)
 528                 return cachep;
 529         if (gfp & __GFP_NOFAIL)
 530                 return cachep;
 531         if (in_interrupt() || (!current->mm) || (current->flags & PF_KTHREAD))
 532                 return cachep;
 533         if (unlikely(fatal_signal_pending(current)))
 534                 return cachep;
 535
 536         return __memcg_kmem_get_cache(cachep);
 537 }
 538
 539 static __always_inline void memcg_kmem_put_cache(struct kmem_cache *cachep)
 540 {
 541         if (memcg_kmem_enabled())
 542                 __memcg_kmem_put_cache(cachep);
 543 }
 544
 545 static __always_inline struct mem_cgroup *mem_cgroup_from_kmem(void *ptr)
 546 {
 547         if (!memcg_kmem_enabled())
 548                 return NULL;
 549         return __mem_cgroup_from_kmem(ptr);
 550 }
 551 #else
 552 #define for_each_memcg_cache_index(_idx)        \
 553         for (; NULL; )
 554
 555 static inline bool memcg_kmem_enabled(void)
 556 {
 557         return false;
 558 }
 559
 560 static inline bool memcg_kmem_is_active(struct mem_cgroup *memcg)
 561 {
 562         return false;
 563 }
 564
 565 static inline bool
 566 memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **memcg, int order)
 567 {
 568         return true;
 569 }
 570
 571 static inline void memcg_kmem_uncharge_pages(struct page *page, int order)
 572 {
 573 }
 574
 575 static inline void
 576 memcg_kmem_commit_charge(struct page *page, struct mem_cgroup *memcg, int order)
 577 {
 578 }
 579
 580 static inline int memcg_cache_id(struct mem_cgroup *memcg)
 581 {
 582         return -1;
 583 }
 584
 585 static inline void memcg_get_cache_ids(void)
 586 {
 587 }
 588
 589 static inline void memcg_put_cache_ids(void)
 590 {
 591 }
 592
 593 static inline struct kmem_cache *
 594 memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp)
 595 {
 596         return cachep;
 597 }
 598
 599 static inline void memcg_kmem_put_cache(struct kmem_cache *cachep)
 600 {
 601 }
 602
 603 static inline struct mem_cgroup *mem_cgroup_from_kmem(void *ptr)
 604 {
 605         return NULL;
 606 }
 607 #endif /* CONFIG_MEMCG_KMEM */
 608 #endif /* _LINUX_MEMCONTROL_H */
 609