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
  32 struct mem_cgroup;
  33 struct page;
  34 struct mm_struct;
  35 struct kmem_cache;
  36
  37 /*
  38  * The corresponding mem_cgroup_stat_names is defined in mm/memcontrol.c,
  39  * These two lists should keep in accord with each other.
  40  */
  41 enum mem_cgroup_stat_index {
  42         /*
  43          * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
  44          */
  45         MEM_CGROUP_STAT_CACHE,          /* # of pages charged as cache */
  46         MEM_CGROUP_STAT_RSS,            /* # of pages charged as anon rss */
  47         MEM_CGROUP_STAT_RSS_HUGE,       /* # of pages charged as anon huge */
  48         MEM_CGROUP_STAT_FILE_MAPPED,    /* # of pages charged as file rss */
  49         MEM_CGROUP_STAT_DIRTY,          /* # of dirty pages in page cache */
  50         MEM_CGROUP_STAT_WRITEBACK,      /* # of pages under writeback */
  51         MEM_CGROUP_STAT_SWAP,           /* # of pages, swapped out */
  52         MEM_CGROUP_STAT_NSTATS,
  53 };
  54
  55 struct mem_cgroup_reclaim_cookie {
  56         struct zone *zone;
  57         int priority;
  58         unsigned int generation;
  59 };
  60
  61 enum mem_cgroup_events_index {
  62         MEM_CGROUP_EVENTS_PGPGIN,       /* # of pages paged in */
  63         MEM_CGROUP_EVENTS_PGPGOUT,      /* # of pages paged out */
  64         MEM_CGROUP_EVENTS_PGFAULT,      /* # of page-faults */
  65         MEM_CGROUP_EVENTS_PGMAJFAULT,   /* # of major page-faults */
  66         MEM_CGROUP_EVENTS_NSTATS,
  67         /* default hierarchy events */
  68         MEMCG_LOW = MEM_CGROUP_EVENTS_NSTATS,
  69         MEMCG_HIGH,
  70         MEMCG_MAX,
  71         MEMCG_OOM,
  72         MEMCG_NR_EVENTS,
  73 };
  74
  75 /*
  76  * Per memcg event counter is incremented at every pagein/pageout. With THP,
  77  * it will be incremated by the number of pages. This counter is used for
  78  * for trigger some periodic events. This is straightforward and better
  79  * than using jiffies etc. to handle periodic memcg event.
  80  */
  81 enum mem_cgroup_events_target {
  82         MEM_CGROUP_TARGET_THRESH,
  83         MEM_CGROUP_TARGET_SOFTLIMIT,
  84         MEM_CGROUP_TARGET_NUMAINFO,
  85         MEM_CGROUP_NTARGETS,
  86 };
  87
  88 struct cg_proto {
  89         struct page_counter     memory_allocated;       /* Current allocated memory. */
  90         int                     memory_pressure;
  91         bool                    active;
  92 };
  93
  94 #ifdef CONFIG_MEMCG
  95 struct mem_cgroup_stat_cpu {
  96         long count[MEM_CGROUP_STAT_NSTATS];
  97         unsigned long events[MEMCG_NR_EVENTS];
  98         unsigned long nr_page_events;
  99         unsigned long targets[MEM_CGROUP_NTARGETS];
 100 };
 101
 102 struct mem_cgroup_reclaim_iter {
 103         struct mem_cgroup *position;
 104         /* scan generation, increased every round-trip */
 105         unsigned int generation;
 106 };
 107
 108 /*
 109  * per-zone information in memory controller.
 110  */
 111 struct mem_cgroup_per_zone {
 112         struct lruvec           lruvec;
 113         unsigned long           lru_size[NR_LRU_LISTS];
 114
 115         struct mem_cgroup_reclaim_iter  iter[DEF_PRIORITY + 1];
 116
 117         struct rb_node          tree_node;      /* RB tree node */
 118         unsigned long           usage_in_excess;/* Set to the value by which */
 119                                                 /* the soft limit is exceeded*/
 120         bool                    on_tree;
 121         struct mem_cgroup       *memcg;         /* Back pointer, we cannot */
 122                                                 /* use container_of        */
 123 };
 124
 125 struct mem_cgroup_per_node {
 126         struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES];
 127 };
 128
 129 struct mem_cgroup_threshold {
 130         struct eventfd_ctx *eventfd;
 131         unsigned long threshold;
 132 };
 133
 134 /* For threshold */
 135 struct mem_cgroup_threshold_ary {
 136         /* An array index points to threshold just below or equal to usage. */
 137         int current_threshold;
 138         /* Size of entries[] */
 139         unsigned int size;
 140         /* Array of thresholds */
 141         struct mem_cgroup_threshold entries[0];
 142 };
 143
 144 struct mem_cgroup_thresholds {
 145         /* Primary thresholds array */
 146         struct mem_cgroup_threshold_ary *primary;
 147         /*
 148          * Spare threshold array.
 149          * This is needed to make mem_cgroup_unregister_event() "never fail".
 150          * It must be able to store at least primary->size - 1 entries.
 151          */
 152         struct mem_cgroup_threshold_ary *spare;
 153 };
 154
 155 enum memcg_kmem_state {
 156         KMEM_NONE,
 157         KMEM_ALLOCATED,
 158         KMEM_ONLINE,
 159 };
 160
 161 /*
 162  * The memory controller data structure. The memory controller controls both
 163  * page cache and RSS per cgroup. We would eventually like to provide
 164  * statistics based on the statistics developed by Rik Van Riel for clock-pro,
 165  * to help the administrator determine what knobs to tune.
 166  */
 167 struct mem_cgroup {
 168         struct cgroup_subsys_state css;
 169
 170         /* Accounted resources */
 171         struct page_counter memory;
 172         struct page_counter memsw;
 173         struct page_counter kmem;
 174
 175         /* Normal memory consumption range */
 176         unsigned long low;
 177         unsigned long high;
 178
 179         /* Range enforcement for interrupt charges */
 180         struct work_struct high_work;
 181
 182         unsigned long soft_limit;
 183
 184         /* vmpressure notifications */
 185         struct vmpressure vmpressure;
 186
 187         /* css_online() has been completed */
 188         int initialized;
 189
 190         /*
 191          * Should the accounting and control be hierarchical, per subtree?
 192          */
 193         bool use_hierarchy;
 194
 195         /* protected by memcg_oom_lock */
 196         bool            oom_lock;
 197         int             under_oom;
 198
 199         int     swappiness;
 200         /* OOM-Killer disable */
 201         int             oom_kill_disable;
 202
 203         /* handle for "memory.events" */
 204         struct cgroup_file events_file;
 205
 206         /* protect arrays of thresholds */
 207         struct mutex thresholds_lock;
 208
 209         /* thresholds for memory usage. RCU-protected */
 210         struct mem_cgroup_thresholds thresholds;
 211
 212         /* thresholds for mem+swap usage. RCU-protected */
 213         struct mem_cgroup_thresholds memsw_thresholds;
 214
 215         /* For oom notifier event fd */
 216         struct list_head oom_notify;
 217
 218         /*
 219          * Should we move charges of a task when a task is moved into this
 220          * mem_cgroup ? And what type of charges should we move ?
 221          */
 222         unsigned long move_charge_at_immigrate;
 223         /*
 224          * set > 0 if pages under this cgroup are moving to other cgroup.
 225          */
 226         atomic_t                moving_account;
 227         /* taken only while moving_account > 0 */
 228         spinlock_t              move_lock;
 229         struct task_struct      *move_lock_task;
 230         unsigned long           move_lock_flags;
 231         /*
 232          * percpu counter.
 233          */
 234         struct mem_cgroup_stat_cpu __percpu *stat;
 235
 236 #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_INET)
 237         struct cg_proto tcp_mem;
 238 #endif
 239 #ifndef CONFIG_SLOB
 240         /* Index in the kmem_cache->memcg_params.memcg_caches array */
 241         int kmemcg_id;
 242         enum memcg_kmem_state kmem_state;
 243 #endif
 244
 245         int last_scanned_node;
 246 #if MAX_NUMNODES > 1
 247         nodemask_t      scan_nodes;
 248         atomic_t        numainfo_events;
 249         atomic_t        numainfo_updating;
 250 #endif
 251
 252 #ifdef CONFIG_CGROUP_WRITEBACK
 253         struct list_head cgwb_list;
 254         struct wb_domain cgwb_domain;
 255 #endif
 256
 257 #ifdef CONFIG_INET
 258         unsigned long           socket_pressure;
 259 #endif
 260
 261         /* List of events which userspace want to receive */
 262         struct list_head event_list;
 263         spinlock_t event_list_lock;
 264
 265         struct mem_cgroup_per_node *nodeinfo[0];
 266         /* WARNING: nodeinfo must be the last member here */
 267 };
 268
 269 extern struct mem_cgroup *root_mem_cgroup;
 270
 271 /**
 272  * mem_cgroup_events - count memory events against a cgroup
 273  * @memcg: the memory cgroup
 274  * @idx: the event index
 275  * @nr: the number of events to account for
 276  */
 277 static inline void mem_cgroup_events(struct mem_cgroup *memcg,
 278                        enum mem_cgroup_events_index idx,
 279                        unsigned int nr)
 280 {
 281         this_cpu_add(memcg->stat->events[idx], nr);
 282         cgroup_file_notify(&memcg->events_file);
 283 }
 284
 285 bool mem_cgroup_low(struct mem_cgroup *root, struct mem_cgroup *memcg);
 286
 287 int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
 288                           gfp_t gfp_mask, struct mem_cgroup **memcgp,
 289                           bool compound);
 290 void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
 291                               bool lrucare, bool compound);
 292 void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg,
 293                 bool compound);
 294 void mem_cgroup_uncharge(struct page *page);
 295 void mem_cgroup_uncharge_list(struct list_head *page_list);
 296
 297 void mem_cgroup_replace_page(struct page *oldpage, struct page *newpage);
 298
 299 struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *);
 300 struct lruvec *mem_cgroup_page_lruvec(struct page *, struct zone *);
 301
 302 bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg);
 303 struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
 304
 305 static inline
 306 struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css){
 307         return css ? container_of(css, struct mem_cgroup, css) : NULL;
 308 }
 309
 310 #define mem_cgroup_from_counter(counter, member)        \
 311         container_of(counter, struct mem_cgroup, member)
 312
 313 struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *,
 314                                    struct mem_cgroup *,
 315                                    struct mem_cgroup_reclaim_cookie *);
 316 void mem_cgroup_iter_break(struct mem_cgroup *, struct mem_cgroup *);
 317
 318 /**
 319  * parent_mem_cgroup - find the accounting parent of a memcg
 320  * @memcg: memcg whose parent to find
 321  *
 322  * Returns the parent memcg, or NULL if this is the root or the memory
 323  * controller is in legacy no-hierarchy mode.
 324  */
 325 static inline struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg)
 326 {
 327         if (!memcg->memory.parent)
 328                 return NULL;
 329         return mem_cgroup_from_counter(memcg->memory.parent, memory);
 330 }
 331
 332 static inline bool mem_cgroup_is_descendant(struct mem_cgroup *memcg,
 333                               struct mem_cgroup *root)
 334 {
 335         if (root == memcg)
 336                 return true;
 337         if (!root->use_hierarchy)
 338                 return false;
 339         return cgroup_is_descendant(memcg->css.cgroup, root->css.cgroup);
 340 }
 341
 342 static inline bool mm_match_cgroup(struct mm_struct *mm,
 343                                    struct mem_cgroup *memcg)
 344 {
 345         struct mem_cgroup *task_memcg;
 346         bool match = false;
 347
 348         rcu_read_lock();
 349         task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
 350         if (task_memcg)
 351                 match = mem_cgroup_is_descendant(task_memcg, memcg);
 352         rcu_read_unlock();
 353         return match;
 354 }
 355
 356 struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page);
 357 ino_t page_cgroup_ino(struct page *page);
 358
 359 static inline bool mem_cgroup_disabled(void)
 360 {
 361         return !cgroup_subsys_enabled(memory_cgrp_subsys);
 362 }
 363
 364 /*
 365  * For memory reclaim.
 366  */
 367 int mem_cgroup_select_victim_node(struct mem_cgroup *memcg);
 368
 369 void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
 370                 int nr_pages);
 371
 372 static inline bool mem_cgroup_lruvec_online(struct lruvec *lruvec)
 373 {
 374         struct mem_cgroup_per_zone *mz;
 375         struct mem_cgroup *memcg;
 376
 377         if (mem_cgroup_disabled())
 378                 return true;
 379
 380         mz = container_of(lruvec, struct mem_cgroup_per_zone, lruvec);
 381         memcg = mz->memcg;
 382
 383         return !!(memcg->css.flags & CSS_ONLINE);
 384 }
 385
 386 static inline
 387 unsigned long mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
 388 {
 389         struct mem_cgroup_per_zone *mz;
 390
 391         mz = container_of(lruvec, struct mem_cgroup_per_zone, lruvec);
 392         return mz->lru_size[lru];
 393 }
 394
 395 static inline bool mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec)
 396 {
 397         unsigned long inactive_ratio;
 398         unsigned long inactive;
 399         unsigned long active;
 400         unsigned long gb;
 401
 402         inactive = mem_cgroup_get_lru_size(lruvec, LRU_INACTIVE_ANON);
 403         active = mem_cgroup_get_lru_size(lruvec, LRU_ACTIVE_ANON);
 404
 405         gb = (inactive + active) >> (30 - PAGE_SHIFT);
 406         if (gb)
 407                 inactive_ratio = int_sqrt(10 * gb);
 408         else
 409                 inactive_ratio = 1;
 410
 411         return inactive * inactive_ratio < active;
 412 }
 413
 414 void mem_cgroup_handle_over_high(void);
 415
 416 void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
 417                                 struct task_struct *p);
 418
 419 static inline void mem_cgroup_oom_enable(void)
 420 {
 421         WARN_ON(current->memcg_may_oom);
 422         current->memcg_may_oom = 1;
 423 }
 424
 425 static inline void mem_cgroup_oom_disable(void)
 426 {
 427         WARN_ON(!current->memcg_may_oom);
 428         current->memcg_may_oom = 0;
 429 }
 430
 431 static inline bool task_in_memcg_oom(struct task_struct *p)
 432 {
 433         return p->memcg_in_oom;
 434 }
 435
 436 bool mem_cgroup_oom_synchronize(bool wait);
 437
 438 #ifdef CONFIG_MEMCG_SWAP
 439 extern int do_swap_account;
 440 #endif
 441
 442 struct mem_cgroup *mem_cgroup_begin_page_stat(struct page *page);
 443 void mem_cgroup_end_page_stat(struct mem_cgroup *memcg);
 444
 445 /**
 446  * mem_cgroup_update_page_stat - update page state statistics
 447  * @memcg: memcg to account against
 448  * @idx: page state item to account
 449  * @val: number of pages (positive or negative)
 450  *
 451  * See mem_cgroup_begin_page_stat() for locking requirements.
 452  */
 453 static inline void mem_cgroup_update_page_stat(struct mem_cgroup *memcg,
 454                                  enum mem_cgroup_stat_index idx, int val)
 455 {
 456         VM_BUG_ON(!rcu_read_lock_held());
 457
 458         if (memcg)
 459                 this_cpu_add(memcg->stat->count[idx], val);
 460 }
 461
 462 static inline void mem_cgroup_inc_page_stat(struct mem_cgroup *memcg,
 463                                             enum mem_cgroup_stat_index idx)
 464 {
 465         mem_cgroup_update_page_stat(memcg, idx, 1);
 466 }
 467
 468 static inline void mem_cgroup_dec_page_stat(struct mem_cgroup *memcg,
 469                                             enum mem_cgroup_stat_index idx)
 470 {
 471         mem_cgroup_update_page_stat(memcg, idx, -1);
 472 }
 473
 474 unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
 475                                                 gfp_t gfp_mask,
 476                                                 unsigned long *total_scanned);
 477
 478 static inline void mem_cgroup_count_vm_event(struct mm_struct *mm,
 479                                              enum vm_event_item idx)
 480 {
 481         struct mem_cgroup *memcg;
 482
 483         if (mem_cgroup_disabled())
 484                 return;
 485
 486         rcu_read_lock();
 487         memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
 488         if (unlikely(!memcg))
 489                 goto out;
 490
 491         switch (idx) {
 492         case PGFAULT:
 493                 this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT]);
 494                 break;
 495         case PGMAJFAULT:
 496                 this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT]);
 497                 break;
 498         default:
 499                 BUG();
 500         }
 501 out:
 502         rcu_read_unlock();
 503 }
 504 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 505 void mem_cgroup_split_huge_fixup(struct page *head);
 506 #endif
 507
 508 #else /* CONFIG_MEMCG */
 509 struct mem_cgroup;
 510
 511 static inline void mem_cgroup_events(struct mem_cgroup *memcg,
 512                                      enum mem_cgroup_events_index idx,
 513                                      unsigned int nr)
 514 {
 515 }
 516
 517 static inline bool mem_cgroup_low(struct mem_cgroup *root,
 518                                   struct mem_cgroup *memcg)
 519 {
 520         return false;
 521 }
 522
 523 static inline int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
 524                                         gfp_t gfp_mask,
 525                                         struct mem_cgroup **memcgp,
 526                                         bool compound)
 527 {
 528         *memcgp = NULL;
 529         return 0;
 530 }
 531
 532 static inline void mem_cgroup_commit_charge(struct page *page,
 533                                             struct mem_cgroup *memcg,
 534                                             bool lrucare, bool compound)
 535 {
 536 }
 537
 538 static inline void mem_cgroup_cancel_charge(struct page *page,
 539                                             struct mem_cgroup *memcg,
 540                                             bool compound)
 541 {
 542 }
 543
 544 static inline void mem_cgroup_uncharge(struct page *page)
 545 {
 546 }
 547
 548 static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
 549 {
 550 }
 551
 552 static inline void mem_cgroup_replace_page(struct page *old, struct page *new)
 553 {
 554 }
 555
 556 static inline struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone,
 557                                                     struct mem_cgroup *memcg)
 558 {
 559         return &zone->lruvec;
 560 }
 561
 562 static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
 563                                                     struct zone *zone)
 564 {
 565         return &zone->lruvec;
 566 }
 567
 568 static inline bool mm_match_cgroup(struct mm_struct *mm,
 569                 struct mem_cgroup *memcg)
 570 {
 571         return true;
 572 }
 573
 574 static inline bool task_in_mem_cgroup(struct task_struct *task,
 575                                       const struct mem_cgroup *memcg)
 576 {
 577         return true;
 578 }
 579
 580 static inline struct mem_cgroup *
 581 mem_cgroup_iter(struct mem_cgroup *root,
 582                 struct mem_cgroup *prev,
 583                 struct mem_cgroup_reclaim_cookie *reclaim)
 584 {
 585         return NULL;
 586 }
 587
 588 static inline void mem_cgroup_iter_break(struct mem_cgroup *root,
 589                                          struct mem_cgroup *prev)
 590 {
 591 }
 592
 593 static inline bool mem_cgroup_disabled(void)
 594 {
 595         return true;
 596 }
 597
 598 static inline bool
 599 mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec)
 600 {
 601         return true;
 602 }
 603
 604 static inline bool mem_cgroup_lruvec_online(struct lruvec *lruvec)
 605 {
 606         return true;
 607 }
 608
 609 static inline unsigned long
 610 mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
 611 {
 612         return 0;
 613 }
 614
 615 static inline void
 616 mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
 617                               int increment)
 618 {
 619 }
 620
 621 static inline void
 622 mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
 623 {
 624 }
 625
 626 static inline struct mem_cgroup *mem_cgroup_begin_page_stat(struct page *page)
 627 {
 628         return NULL;
 629 }
 630
 631 static inline void mem_cgroup_end_page_stat(struct mem_cgroup *memcg)
 632 {
 633 }
 634
 635 static inline void mem_cgroup_handle_over_high(void)
 636 {
 637 }
 638
 639 static inline void mem_cgroup_oom_enable(void)
 640 {
 641 }
 642
 643 static inline void mem_cgroup_oom_disable(void)
 644 {
 645 }
 646
 647 static inline bool task_in_memcg_oom(struct task_struct *p)
 648 {
 649         return false;
 650 }
 651
 652 static inline bool mem_cgroup_oom_synchronize(bool wait)
 653 {
 654         return false;
 655 }
 656
 657 static inline void mem_cgroup_inc_page_stat(struct mem_cgroup *memcg,
 658                                             enum mem_cgroup_stat_index idx)
 659 {
 660 }
 661
 662 static inline void mem_cgroup_dec_page_stat(struct mem_cgroup *memcg,
 663                                             enum mem_cgroup_stat_index idx)
 664 {
 665 }
 666
 667 static inline
 668 unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
 669                                             gfp_t gfp_mask,
 670                                             unsigned long *total_scanned)
 671 {
 672         return 0;
 673 }
 674
 675 static inline void mem_cgroup_split_huge_fixup(struct page *head)
 676 {
 677 }
 678
 679 static inline
 680 void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
 681 {
 682 }
 683 #endif /* CONFIG_MEMCG */
 684
 685 #ifdef CONFIG_CGROUP_WRITEBACK
 686
 687 struct list_head *mem_cgroup_cgwb_list(struct mem_cgroup *memcg);
 688 struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb);
 689 void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
 690                          unsigned long *pheadroom, unsigned long *pdirty,
 691                          unsigned long *pwriteback);
 692
 693 #else   /* CONFIG_CGROUP_WRITEBACK */
 694
 695 static inline struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb)
 696 {
 697         return NULL;
 698 }
 699
 700 static inline void mem_cgroup_wb_stats(struct bdi_writeback *wb,
 701                                        unsigned long *pfilepages,
 702                                        unsigned long *pheadroom,
 703                                        unsigned long *pdirty,
 704                                        unsigned long *pwriteback)
 705 {
 706 }
 707
 708 #endif  /* CONFIG_CGROUP_WRITEBACK */
 709
 710 struct sock;
 711 void sock_update_memcg(struct sock *sk);
 712 void sock_release_memcg(struct sock *sk);
 713 bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
 714 void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
 715 #if defined(CONFIG_MEMCG) && defined(CONFIG_INET)
 716 extern struct static_key_false memcg_sockets_enabled_key;
 717 #define mem_cgroup_sockets_enabled static_branch_unlikely(&memcg_sockets_enabled_key)
 718 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
 719 {
 720 #ifdef CONFIG_MEMCG_KMEM
 721         if (memcg->tcp_mem.memory_pressure)
 722                 return true;
 723 #endif
 724         do {
 725                 if (time_before(jiffies, memcg->socket_pressure))
 726                         return true;
 727         } while ((memcg = parent_mem_cgroup(memcg)));
 728         return false;
 729 }
 730 #else
 731 #define mem_cgroup_sockets_enabled 0
 732 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
 733 {
 734         return false;
 735 }
 736 #endif
 737
 738 #if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
 739 extern struct static_key_false memcg_kmem_enabled_key;
 740
 741 extern int memcg_nr_cache_ids;
 742 void memcg_get_cache_ids(void);
 743 void memcg_put_cache_ids(void);
 744
 745 /*
 746  * Helper macro to loop through all memcg-specific caches. Callers must still
 747  * check if the cache is valid (it is either valid or NULL).
 748  * the slab_mutex must be held when looping through those caches
 749  */
 750 #define for_each_memcg_cache_index(_idx)        \
 751         for ((_idx) = 0; (_idx) < memcg_nr_cache_ids; (_idx)++)
 752
 753 static inline bool memcg_kmem_enabled(void)
 754 {
 755         return static_branch_unlikely(&memcg_kmem_enabled_key);
 756 }
 757
 758 static inline bool memcg_kmem_online(struct mem_cgroup *memcg)
 759 {
 760         return memcg->kmem_state == KMEM_ONLINE;
 761 }
 762
 763 /*
 764  * In general, we'll do everything in our power to not incur in any overhead
 765  * for non-memcg users for the kmem functions. Not even a function call, if we
 766  * can avoid it.
 767  *
 768  * Therefore, we'll inline all those functions so that in the best case, we'll
 769  * see that kmemcg is off for everybody and proceed quickly.  If it is on,
 770  * we'll still do most of the flag checking inline. We check a lot of
 771  * conditions, but because they are pretty simple, they are expected to be
 772  * fast.
 773  */
 774 int __memcg_kmem_charge_memcg(struct page *page, gfp_t gfp, int order,
 775                               struct mem_cgroup *memcg);
 776 int __memcg_kmem_charge(struct page *page, gfp_t gfp, int order);
 777 void __memcg_kmem_uncharge(struct page *page, int order);
 778
 779 /*
 780  * helper for acessing a memcg's index. It will be used as an index in the
 781  * child cache array in kmem_cache, and also to derive its name. This function
 782  * will return -1 when this is not a kmem-limited memcg.
 783  */
 784 static inline int memcg_cache_id(struct mem_cgroup *memcg)
 785 {
 786         return memcg ? memcg->kmemcg_id : -1;
 787 }
 788
 789 struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp);
 790 void __memcg_kmem_put_cache(struct kmem_cache *cachep);
 791
 792 static inline bool __memcg_kmem_bypass(void)
 793 {
 794         if (!memcg_kmem_enabled())
 795                 return true;
 796         if (in_interrupt() || (!current->mm) || (current->flags & PF_KTHREAD))
 797                 return true;
 798         return false;
 799 }
 800
 801 /**
 802  * memcg_kmem_charge: charge a kmem page
 803  * @page: page to charge
 804  * @gfp: reclaim mode
 805  * @order: allocation order
 806  *
 807  * Returns 0 on success, an error code on failure.
 808  */
 809 static __always_inline int memcg_kmem_charge(struct page *page,
 810                                              gfp_t gfp, int order)
 811 {
 812         if (__memcg_kmem_bypass())
 813                 return 0;
 814         if (!(gfp & __GFP_ACCOUNT))
 815                 return 0;
 816         return __memcg_kmem_charge(page, gfp, order);
 817 }
 818
 819 /**
 820  * memcg_kmem_uncharge: uncharge a kmem page
 821  * @page: page to uncharge
 822  * @order: allocation order
 823  */
 824 static __always_inline void memcg_kmem_uncharge(struct page *page, int order)
 825 {
 826         if (memcg_kmem_enabled())
 827                 __memcg_kmem_uncharge(page, order);
 828 }
 829
 830 /**
 831  * memcg_kmem_get_cache: selects the correct per-memcg cache for allocation
 832  * @cachep: the original global kmem cache
 833  *
 834  * All memory allocated from a per-memcg cache is charged to the owner memcg.
 835  */
 836 static __always_inline struct kmem_cache *
 837 memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp)
 838 {
 839         if (__memcg_kmem_bypass())
 840                 return cachep;
 841         return __memcg_kmem_get_cache(cachep, gfp);
 842 }
 843
 844 static __always_inline void memcg_kmem_put_cache(struct kmem_cache *cachep)
 845 {
 846         if (memcg_kmem_enabled())
 847                 __memcg_kmem_put_cache(cachep);
 848 }
 849 #else
 850 #define for_each_memcg_cache_index(_idx)        \
 851         for (; NULL; )
 852
 853 static inline bool memcg_kmem_enabled(void)
 854 {
 855         return false;
 856 }
 857
 858 static inline bool memcg_kmem_online(struct mem_cgroup *memcg)
 859 {
 860         return false;
 861 }
 862
 863 static inline int memcg_kmem_charge(struct page *page, gfp_t gfp, int order)
 864 {
 865         return 0;
 866 }
 867
 868 static inline void memcg_kmem_uncharge(struct page *page, int order)
 869 {
 870 }
 871
 872 static inline int memcg_cache_id(struct mem_cgroup *memcg)
 873 {
 874         return -1;
 875 }
 876
 877 static inline void memcg_get_cache_ids(void)
 878 {
 879 }
 880
 881 static inline void memcg_put_cache_ids(void)
 882 {
 883 }
 884
 885 static inline struct kmem_cache *
 886 memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp)
 887 {
 888         return cachep;
 889 }
 890
 891 static inline void memcg_kmem_put_cache(struct kmem_cache *cachep)
 892 {
 893 }
 894 #endif /* CONFIG_MEMCG && !CONFIG_SLOB */
 895
 896 #endif /* _LINUX_MEMCONTROL_H */