xref: /linux-6.15/include/linux/memcontrol.h (revision ec2da07c)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* memcontrol.h - Memory Controller
3  *
4  * Copyright IBM Corporation, 2007
5  * Author Balbir Singh <[email protected]>
6  *
7  * Copyright 2007 OpenVZ SWsoft Inc
8  * Author: Pavel Emelianov <[email protected]>
9  */
10 
11 #ifndef _LINUX_MEMCONTROL_H
12 #define _LINUX_MEMCONTROL_H
13 #include <linux/cgroup.h>
14 #include <linux/vm_event_item.h>
15 #include <linux/hardirq.h>
16 #include <linux/jump_label.h>
17 #include <linux/page_counter.h>
18 #include <linux/vmpressure.h>
19 #include <linux/eventfd.h>
20 #include <linux/mm.h>
21 #include <linux/vmstat.h>
22 #include <linux/writeback.h>
23 #include <linux/page-flags.h>
24 
25 struct mem_cgroup;
26 struct page;
27 struct mm_struct;
28 struct kmem_cache;
29 
30 /* Cgroup-specific page state, on top of universal node page state */
31 enum memcg_stat_item {
32 	MEMCG_CACHE = NR_VM_NODE_STAT_ITEMS,
33 	MEMCG_RSS,
34 	MEMCG_RSS_HUGE,
35 	MEMCG_SWAP,
36 	MEMCG_SOCK,
37 	/* XXX: why are these zone and not node counters? */
38 	MEMCG_KERNEL_STACK_KB,
39 	MEMCG_NR_STAT,
40 };
41 
42 enum memcg_memory_event {
43 	MEMCG_LOW,
44 	MEMCG_HIGH,
45 	MEMCG_MAX,
46 	MEMCG_OOM,
47 	MEMCG_OOM_KILL,
48 	MEMCG_SWAP_MAX,
49 	MEMCG_SWAP_FAIL,
50 	MEMCG_NR_MEMORY_EVENTS,
51 };
52 
53 enum mem_cgroup_protection {
54 	MEMCG_PROT_NONE,
55 	MEMCG_PROT_LOW,
56 	MEMCG_PROT_MIN,
57 };
58 
59 struct mem_cgroup_reclaim_cookie {
60 	pg_data_t *pgdat;
61 	int priority;
62 	unsigned int generation;
63 };
64 
65 #ifdef CONFIG_MEMCG
66 
67 #define MEM_CGROUP_ID_SHIFT	16
68 #define MEM_CGROUP_ID_MAX	USHRT_MAX
69 
70 struct mem_cgroup_id {
71 	int id;
72 	refcount_t ref;
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 memcg_vmstats_percpu {
89 	long stat[MEMCG_NR_STAT];
90 	unsigned long events[NR_VM_EVENT_ITEMS];
91 	unsigned long nr_page_events;
92 	unsigned long targets[MEM_CGROUP_NTARGETS];
93 };
94 
95 struct mem_cgroup_reclaim_iter {
96 	struct mem_cgroup *position;
97 	/* scan generation, increased every round-trip */
98 	unsigned int generation;
99 };
100 
101 struct lruvec_stat {
102 	long count[NR_VM_NODE_STAT_ITEMS];
103 };
104 
105 /*
106  * Bitmap of shrinker::id corresponding to memcg-aware shrinkers,
107  * which have elements charged to this memcg.
108  */
109 struct memcg_shrinker_map {
110 	struct rcu_head rcu;
111 	unsigned long map[0];
112 };
113 
114 /*
115  * per-zone information in memory controller.
116  */
117 struct mem_cgroup_per_node {
118 	struct lruvec		lruvec;
119 
120 	/* Legacy local VM stats */
121 	struct lruvec_stat __percpu *lruvec_stat_local;
122 
123 	/* Subtree VM stats (batched updates) */
124 	struct lruvec_stat __percpu *lruvec_stat_cpu;
125 	atomic_long_t		lruvec_stat[NR_VM_NODE_STAT_ITEMS];
126 
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 #ifdef CONFIG_MEMCG_KMEM
132 	struct memcg_shrinker_map __rcu	*shrinker_map;
133 #endif
134 	struct rb_node		tree_node;	/* RB tree node */
135 	unsigned long		usage_in_excess;/* Set to the value by which */
136 						/* the soft limit is exceeded*/
137 	bool			on_tree;
138 	bool			congested;	/* memcg has many dirty pages */
139 						/* backed by a congested BDI */
140 
141 	struct mem_cgroup	*memcg;		/* Back pointer, we cannot */
142 						/* use container_of	   */
143 };
144 
145 struct mem_cgroup_threshold {
146 	struct eventfd_ctx *eventfd;
147 	unsigned long threshold;
148 };
149 
150 /* For threshold */
151 struct mem_cgroup_threshold_ary {
152 	/* An array index points to threshold just below or equal to usage. */
153 	int current_threshold;
154 	/* Size of entries[] */
155 	unsigned int size;
156 	/* Array of thresholds */
157 	struct mem_cgroup_threshold entries[0];
158 };
159 
160 struct mem_cgroup_thresholds {
161 	/* Primary thresholds array */
162 	struct mem_cgroup_threshold_ary *primary;
163 	/*
164 	 * Spare threshold array.
165 	 * This is needed to make mem_cgroup_unregister_event() "never fail".
166 	 * It must be able to store at least primary->size - 1 entries.
167 	 */
168 	struct mem_cgroup_threshold_ary *spare;
169 };
170 
171 enum memcg_kmem_state {
172 	KMEM_NONE,
173 	KMEM_ALLOCATED,
174 	KMEM_ONLINE,
175 };
176 
177 #if defined(CONFIG_SMP)
178 struct memcg_padding {
179 	char x[0];
180 } ____cacheline_internodealigned_in_smp;
181 #define MEMCG_PADDING(name)      struct memcg_padding name;
182 #else
183 #define MEMCG_PADDING(name)
184 #endif
185 
186 /*
187  * The memory controller data structure. The memory controller controls both
188  * page cache and RSS per cgroup. We would eventually like to provide
189  * statistics based on the statistics developed by Rik Van Riel for clock-pro,
190  * to help the administrator determine what knobs to tune.
191  */
192 struct mem_cgroup {
193 	struct cgroup_subsys_state css;
194 
195 	/* Private memcg ID. Used to ID objects that outlive the cgroup */
196 	struct mem_cgroup_id id;
197 
198 	/* Accounted resources */
199 	struct page_counter memory;
200 	struct page_counter swap;
201 
202 	/* Legacy consumer-oriented counters */
203 	struct page_counter memsw;
204 	struct page_counter kmem;
205 	struct page_counter tcpmem;
206 
207 	/* Upper bound of normal memory consumption range */
208 	unsigned long high;
209 
210 	/* Range enforcement for interrupt charges */
211 	struct work_struct high_work;
212 
213 	unsigned long soft_limit;
214 
215 	/* vmpressure notifications */
216 	struct vmpressure vmpressure;
217 
218 	/*
219 	 * Should the accounting and control be hierarchical, per subtree?
220 	 */
221 	bool use_hierarchy;
222 
223 	/*
224 	 * Should the OOM killer kill all belonging tasks, had it kill one?
225 	 */
226 	bool oom_group;
227 
228 	/* protected by memcg_oom_lock */
229 	bool		oom_lock;
230 	int		under_oom;
231 
232 	int	swappiness;
233 	/* OOM-Killer disable */
234 	int		oom_kill_disable;
235 
236 	/* memory.events and memory.events.local */
237 	struct cgroup_file events_file;
238 	struct cgroup_file events_local_file;
239 
240 	/* handle for "memory.swap.events" */
241 	struct cgroup_file swap_events_file;
242 
243 	/* protect arrays of thresholds */
244 	struct mutex thresholds_lock;
245 
246 	/* thresholds for memory usage. RCU-protected */
247 	struct mem_cgroup_thresholds thresholds;
248 
249 	/* thresholds for mem+swap usage. RCU-protected */
250 	struct mem_cgroup_thresholds memsw_thresholds;
251 
252 	/* For oom notifier event fd */
253 	struct list_head oom_notify;
254 
255 	/*
256 	 * Should we move charges of a task when a task is moved into this
257 	 * mem_cgroup ? And what type of charges should we move ?
258 	 */
259 	unsigned long move_charge_at_immigrate;
260 	/* taken only while moving_account > 0 */
261 	spinlock_t		move_lock;
262 	unsigned long		move_lock_flags;
263 
264 	MEMCG_PADDING(_pad1_);
265 
266 	/*
267 	 * set > 0 if pages under this cgroup are moving to other cgroup.
268 	 */
269 	atomic_t		moving_account;
270 	struct task_struct	*move_lock_task;
271 
272 	/* Legacy local VM stats and events */
273 	struct memcg_vmstats_percpu __percpu *vmstats_local;
274 
275 	/* Subtree VM stats and events (batched updates) */
276 	struct memcg_vmstats_percpu __percpu *vmstats_percpu;
277 
278 	MEMCG_PADDING(_pad2_);
279 
280 	atomic_long_t		vmstats[MEMCG_NR_STAT];
281 	atomic_long_t		vmevents[NR_VM_EVENT_ITEMS];
282 
283 	/* memory.events */
284 	atomic_long_t		memory_events[MEMCG_NR_MEMORY_EVENTS];
285 	atomic_long_t		memory_events_local[MEMCG_NR_MEMORY_EVENTS];
286 
287 	unsigned long		socket_pressure;
288 
289 	/* Legacy tcp memory accounting */
290 	bool			tcpmem_active;
291 	int			tcpmem_pressure;
292 
293 #ifdef CONFIG_MEMCG_KMEM
294         /* Index in the kmem_cache->memcg_params.memcg_caches array */
295 	int kmemcg_id;
296 	enum memcg_kmem_state kmem_state;
297 	struct list_head kmem_caches;
298 #endif
299 
300 	int last_scanned_node;
301 #if MAX_NUMNODES > 1
302 	nodemask_t	scan_nodes;
303 	atomic_t	numainfo_events;
304 	atomic_t	numainfo_updating;
305 #endif
306 
307 #ifdef CONFIG_CGROUP_WRITEBACK
308 	struct list_head cgwb_list;
309 	struct wb_domain cgwb_domain;
310 #endif
311 
312 	/* List of events which userspace want to receive */
313 	struct list_head event_list;
314 	spinlock_t event_list_lock;
315 
316 	struct mem_cgroup_per_node *nodeinfo[0];
317 	/* WARNING: nodeinfo must be the last member here */
318 };
319 
320 /*
321  * size of first charge trial. "32" comes from vmscan.c's magic value.
322  * TODO: maybe necessary to use big numbers in big irons.
323  */
324 #define MEMCG_CHARGE_BATCH 32U
325 
326 extern struct mem_cgroup *root_mem_cgroup;
327 
328 static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg)
329 {
330 	return (memcg == root_mem_cgroup);
331 }
332 
333 static inline bool mem_cgroup_disabled(void)
334 {
335 	return !cgroup_subsys_enabled(memory_cgrp_subsys);
336 }
337 
338 enum mem_cgroup_protection mem_cgroup_protected(struct mem_cgroup *root,
339 						struct mem_cgroup *memcg);
340 
341 int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
342 			  gfp_t gfp_mask, struct mem_cgroup **memcgp,
343 			  bool compound);
344 int mem_cgroup_try_charge_delay(struct page *page, struct mm_struct *mm,
345 			  gfp_t gfp_mask, struct mem_cgroup **memcgp,
346 			  bool compound);
347 void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
348 			      bool lrucare, bool compound);
349 void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg,
350 		bool compound);
351 void mem_cgroup_uncharge(struct page *page);
352 void mem_cgroup_uncharge_list(struct list_head *page_list);
353 
354 void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
355 
356 static struct mem_cgroup_per_node *
357 mem_cgroup_nodeinfo(struct mem_cgroup *memcg, int nid)
358 {
359 	return memcg->nodeinfo[nid];
360 }
361 
362 /**
363  * mem_cgroup_lruvec - get the lru list vector for a node or a memcg zone
364  * @node: node of the wanted lruvec
365  * @memcg: memcg of the wanted lruvec
366  *
367  * Returns the lru list vector holding pages for a given @node or a given
368  * @memcg and @zone. This can be the node lruvec, if the memory controller
369  * is disabled.
370  */
371 static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
372 				struct mem_cgroup *memcg)
373 {
374 	struct mem_cgroup_per_node *mz;
375 	struct lruvec *lruvec;
376 
377 	if (mem_cgroup_disabled()) {
378 		lruvec = node_lruvec(pgdat);
379 		goto out;
380 	}
381 
382 	mz = mem_cgroup_nodeinfo(memcg, pgdat->node_id);
383 	lruvec = &mz->lruvec;
384 out:
385 	/*
386 	 * Since a node can be onlined after the mem_cgroup was created,
387 	 * we have to be prepared to initialize lruvec->pgdat here;
388 	 * and if offlined then reonlined, we need to reinitialize it.
389 	 */
390 	if (unlikely(lruvec->pgdat != pgdat))
391 		lruvec->pgdat = pgdat;
392 	return lruvec;
393 }
394 
395 struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *);
396 
397 struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
398 
399 struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm);
400 
401 struct mem_cgroup *get_mem_cgroup_from_page(struct page *page);
402 
403 static inline
404 struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css){
405 	return css ? container_of(css, struct mem_cgroup, css) : NULL;
406 }
407 
408 static inline void mem_cgroup_put(struct mem_cgroup *memcg)
409 {
410 	if (memcg)
411 		css_put(&memcg->css);
412 }
413 
414 #define mem_cgroup_from_counter(counter, member)	\
415 	container_of(counter, struct mem_cgroup, member)
416 
417 struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *,
418 				   struct mem_cgroup *,
419 				   struct mem_cgroup_reclaim_cookie *);
420 void mem_cgroup_iter_break(struct mem_cgroup *, struct mem_cgroup *);
421 int mem_cgroup_scan_tasks(struct mem_cgroup *,
422 			  int (*)(struct task_struct *, void *), void *);
423 
424 static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
425 {
426 	if (mem_cgroup_disabled())
427 		return 0;
428 
429 	return memcg->id.id;
430 }
431 struct mem_cgroup *mem_cgroup_from_id(unsigned short id);
432 
433 static inline struct mem_cgroup *mem_cgroup_from_seq(struct seq_file *m)
434 {
435 	return mem_cgroup_from_css(seq_css(m));
436 }
437 
438 static inline struct mem_cgroup *lruvec_memcg(struct lruvec *lruvec)
439 {
440 	struct mem_cgroup_per_node *mz;
441 
442 	if (mem_cgroup_disabled())
443 		return NULL;
444 
445 	mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
446 	return mz->memcg;
447 }
448 
449 /**
450  * parent_mem_cgroup - find the accounting parent of a memcg
451  * @memcg: memcg whose parent to find
452  *
453  * Returns the parent memcg, or NULL if this is the root or the memory
454  * controller is in legacy no-hierarchy mode.
455  */
456 static inline struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg)
457 {
458 	if (!memcg->memory.parent)
459 		return NULL;
460 	return mem_cgroup_from_counter(memcg->memory.parent, memory);
461 }
462 
463 static inline bool mem_cgroup_is_descendant(struct mem_cgroup *memcg,
464 			      struct mem_cgroup *root)
465 {
466 	if (root == memcg)
467 		return true;
468 	if (!root->use_hierarchy)
469 		return false;
470 	return cgroup_is_descendant(memcg->css.cgroup, root->css.cgroup);
471 }
472 
473 static inline bool mm_match_cgroup(struct mm_struct *mm,
474 				   struct mem_cgroup *memcg)
475 {
476 	struct mem_cgroup *task_memcg;
477 	bool match = false;
478 
479 	rcu_read_lock();
480 	task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
481 	if (task_memcg)
482 		match = mem_cgroup_is_descendant(task_memcg, memcg);
483 	rcu_read_unlock();
484 	return match;
485 }
486 
487 struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page);
488 ino_t page_cgroup_ino(struct page *page);
489 
490 static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
491 {
492 	if (mem_cgroup_disabled())
493 		return true;
494 	return !!(memcg->css.flags & CSS_ONLINE);
495 }
496 
497 /*
498  * For memory reclaim.
499  */
500 int mem_cgroup_select_victim_node(struct mem_cgroup *memcg);
501 
502 void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
503 		int zid, int nr_pages);
504 
505 static inline
506 unsigned long mem_cgroup_get_zone_lru_size(struct lruvec *lruvec,
507 		enum lru_list lru, int zone_idx)
508 {
509 	struct mem_cgroup_per_node *mz;
510 
511 	mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
512 	return mz->lru_zone_size[zone_idx][lru];
513 }
514 
515 void mem_cgroup_handle_over_high(void);
516 
517 unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg);
518 
519 void mem_cgroup_print_oom_context(struct mem_cgroup *memcg,
520 				struct task_struct *p);
521 
522 void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg);
523 
524 static inline void mem_cgroup_enter_user_fault(void)
525 {
526 	WARN_ON(current->in_user_fault);
527 	current->in_user_fault = 1;
528 }
529 
530 static inline void mem_cgroup_exit_user_fault(void)
531 {
532 	WARN_ON(!current->in_user_fault);
533 	current->in_user_fault = 0;
534 }
535 
536 static inline bool task_in_memcg_oom(struct task_struct *p)
537 {
538 	return p->memcg_in_oom;
539 }
540 
541 bool mem_cgroup_oom_synchronize(bool wait);
542 struct mem_cgroup *mem_cgroup_get_oom_group(struct task_struct *victim,
543 					    struct mem_cgroup *oom_domain);
544 void mem_cgroup_print_oom_group(struct mem_cgroup *memcg);
545 
546 #ifdef CONFIG_MEMCG_SWAP
547 extern int do_swap_account;
548 #endif
549 
550 struct mem_cgroup *lock_page_memcg(struct page *page);
551 void __unlock_page_memcg(struct mem_cgroup *memcg);
552 void unlock_page_memcg(struct page *page);
553 
554 /*
555  * idx can be of type enum memcg_stat_item or node_stat_item.
556  * Keep in sync with memcg_exact_page_state().
557  */
558 static inline unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx)
559 {
560 	long x = atomic_long_read(&memcg->vmstats[idx]);
561 #ifdef CONFIG_SMP
562 	if (x < 0)
563 		x = 0;
564 #endif
565 	return x;
566 }
567 
568 /*
569  * idx can be of type enum memcg_stat_item or node_stat_item.
570  * Keep in sync with memcg_exact_page_state().
571  */
572 static inline unsigned long memcg_page_state_local(struct mem_cgroup *memcg,
573 						   int idx)
574 {
575 	long x = 0;
576 	int cpu;
577 
578 	for_each_possible_cpu(cpu)
579 		x += per_cpu(memcg->vmstats_local->stat[idx], cpu);
580 #ifdef CONFIG_SMP
581 	if (x < 0)
582 		x = 0;
583 #endif
584 	return x;
585 }
586 
587 void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val);
588 
589 /* idx can be of type enum memcg_stat_item or node_stat_item */
590 static inline void mod_memcg_state(struct mem_cgroup *memcg,
591 				   int idx, int val)
592 {
593 	unsigned long flags;
594 
595 	local_irq_save(flags);
596 	__mod_memcg_state(memcg, idx, val);
597 	local_irq_restore(flags);
598 }
599 
600 /**
601  * mod_memcg_page_state - update page state statistics
602  * @page: the page
603  * @idx: page state item to account
604  * @val: number of pages (positive or negative)
605  *
606  * The @page must be locked or the caller must use lock_page_memcg()
607  * to prevent double accounting when the page is concurrently being
608  * moved to another memcg:
609  *
610  *   lock_page(page) or lock_page_memcg(page)
611  *   if (TestClearPageState(page))
612  *     mod_memcg_page_state(page, state, -1);
613  *   unlock_page(page) or unlock_page_memcg(page)
614  *
615  * Kernel pages are an exception to this, since they'll never move.
616  */
617 static inline void __mod_memcg_page_state(struct page *page,
618 					  int idx, int val)
619 {
620 	if (page->mem_cgroup)
621 		__mod_memcg_state(page->mem_cgroup, idx, val);
622 }
623 
624 static inline void mod_memcg_page_state(struct page *page,
625 					int idx, int val)
626 {
627 	if (page->mem_cgroup)
628 		mod_memcg_state(page->mem_cgroup, idx, val);
629 }
630 
631 static inline unsigned long lruvec_page_state(struct lruvec *lruvec,
632 					      enum node_stat_item idx)
633 {
634 	struct mem_cgroup_per_node *pn;
635 	long x;
636 
637 	if (mem_cgroup_disabled())
638 		return node_page_state(lruvec_pgdat(lruvec), idx);
639 
640 	pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
641 	x = atomic_long_read(&pn->lruvec_stat[idx]);
642 #ifdef CONFIG_SMP
643 	if (x < 0)
644 		x = 0;
645 #endif
646 	return x;
647 }
648 
649 static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec,
650 						    enum node_stat_item idx)
651 {
652 	struct mem_cgroup_per_node *pn;
653 	long x = 0;
654 	int cpu;
655 
656 	if (mem_cgroup_disabled())
657 		return node_page_state(lruvec_pgdat(lruvec), idx);
658 
659 	pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
660 	for_each_possible_cpu(cpu)
661 		x += per_cpu(pn->lruvec_stat_local->count[idx], cpu);
662 #ifdef CONFIG_SMP
663 	if (x < 0)
664 		x = 0;
665 #endif
666 	return x;
667 }
668 
669 void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
670 			int val);
671 void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val);
672 
673 static inline void mod_lruvec_state(struct lruvec *lruvec,
674 				    enum node_stat_item idx, int val)
675 {
676 	unsigned long flags;
677 
678 	local_irq_save(flags);
679 	__mod_lruvec_state(lruvec, idx, val);
680 	local_irq_restore(flags);
681 }
682 
683 static inline void __mod_lruvec_page_state(struct page *page,
684 					   enum node_stat_item idx, int val)
685 {
686 	pg_data_t *pgdat = page_pgdat(page);
687 	struct lruvec *lruvec;
688 
689 	/* Untracked pages have no memcg, no lruvec. Update only the node */
690 	if (!page->mem_cgroup) {
691 		__mod_node_page_state(pgdat, idx, val);
692 		return;
693 	}
694 
695 	lruvec = mem_cgroup_lruvec(pgdat, page->mem_cgroup);
696 	__mod_lruvec_state(lruvec, idx, val);
697 }
698 
699 static inline void mod_lruvec_page_state(struct page *page,
700 					 enum node_stat_item idx, int val)
701 {
702 	unsigned long flags;
703 
704 	local_irq_save(flags);
705 	__mod_lruvec_page_state(page, idx, val);
706 	local_irq_restore(flags);
707 }
708 
709 unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
710 						gfp_t gfp_mask,
711 						unsigned long *total_scanned);
712 
713 void __count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx,
714 			  unsigned long count);
715 
716 static inline void count_memcg_events(struct mem_cgroup *memcg,
717 				      enum vm_event_item idx,
718 				      unsigned long count)
719 {
720 	unsigned long flags;
721 
722 	local_irq_save(flags);
723 	__count_memcg_events(memcg, idx, count);
724 	local_irq_restore(flags);
725 }
726 
727 static inline void count_memcg_page_event(struct page *page,
728 					  enum vm_event_item idx)
729 {
730 	if (page->mem_cgroup)
731 		count_memcg_events(page->mem_cgroup, idx, 1);
732 }
733 
734 static inline void count_memcg_event_mm(struct mm_struct *mm,
735 					enum vm_event_item idx)
736 {
737 	struct mem_cgroup *memcg;
738 
739 	if (mem_cgroup_disabled())
740 		return;
741 
742 	rcu_read_lock();
743 	memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
744 	if (likely(memcg))
745 		count_memcg_events(memcg, idx, 1);
746 	rcu_read_unlock();
747 }
748 
749 static inline void memcg_memory_event(struct mem_cgroup *memcg,
750 				      enum memcg_memory_event event)
751 {
752 	atomic_long_inc(&memcg->memory_events_local[event]);
753 	cgroup_file_notify(&memcg->events_local_file);
754 
755 	do {
756 		atomic_long_inc(&memcg->memory_events[event]);
757 		cgroup_file_notify(&memcg->events_file);
758 
759 		if (cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_LOCAL_EVENTS)
760 			break;
761 	} while ((memcg = parent_mem_cgroup(memcg)) &&
762 		 !mem_cgroup_is_root(memcg));
763 }
764 
765 static inline void memcg_memory_event_mm(struct mm_struct *mm,
766 					 enum memcg_memory_event event)
767 {
768 	struct mem_cgroup *memcg;
769 
770 	if (mem_cgroup_disabled())
771 		return;
772 
773 	rcu_read_lock();
774 	memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
775 	if (likely(memcg))
776 		memcg_memory_event(memcg, event);
777 	rcu_read_unlock();
778 }
779 
780 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
781 void mem_cgroup_split_huge_fixup(struct page *head);
782 #endif
783 
784 #else /* CONFIG_MEMCG */
785 
786 #define MEM_CGROUP_ID_SHIFT	0
787 #define MEM_CGROUP_ID_MAX	0
788 
789 struct mem_cgroup;
790 
791 static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg)
792 {
793 	return true;
794 }
795 
796 static inline bool mem_cgroup_disabled(void)
797 {
798 	return true;
799 }
800 
801 static inline void memcg_memory_event(struct mem_cgroup *memcg,
802 				      enum memcg_memory_event event)
803 {
804 }
805 
806 static inline void memcg_memory_event_mm(struct mm_struct *mm,
807 					 enum memcg_memory_event event)
808 {
809 }
810 
811 static inline enum mem_cgroup_protection mem_cgroup_protected(
812 	struct mem_cgroup *root, struct mem_cgroup *memcg)
813 {
814 	return MEMCG_PROT_NONE;
815 }
816 
817 static inline int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
818 					gfp_t gfp_mask,
819 					struct mem_cgroup **memcgp,
820 					bool compound)
821 {
822 	*memcgp = NULL;
823 	return 0;
824 }
825 
826 static inline int mem_cgroup_try_charge_delay(struct page *page,
827 					      struct mm_struct *mm,
828 					      gfp_t gfp_mask,
829 					      struct mem_cgroup **memcgp,
830 					      bool compound)
831 {
832 	*memcgp = NULL;
833 	return 0;
834 }
835 
836 static inline void mem_cgroup_commit_charge(struct page *page,
837 					    struct mem_cgroup *memcg,
838 					    bool lrucare, bool compound)
839 {
840 }
841 
842 static inline void mem_cgroup_cancel_charge(struct page *page,
843 					    struct mem_cgroup *memcg,
844 					    bool compound)
845 {
846 }
847 
848 static inline void mem_cgroup_uncharge(struct page *page)
849 {
850 }
851 
852 static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
853 {
854 }
855 
856 static inline void mem_cgroup_migrate(struct page *old, struct page *new)
857 {
858 }
859 
860 static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
861 				struct mem_cgroup *memcg)
862 {
863 	return node_lruvec(pgdat);
864 }
865 
866 static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
867 						    struct pglist_data *pgdat)
868 {
869 	return &pgdat->lruvec;
870 }
871 
872 static inline bool mm_match_cgroup(struct mm_struct *mm,
873 		struct mem_cgroup *memcg)
874 {
875 	return true;
876 }
877 
878 static inline struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm)
879 {
880 	return NULL;
881 }
882 
883 static inline struct mem_cgroup *get_mem_cgroup_from_page(struct page *page)
884 {
885 	return NULL;
886 }
887 
888 static inline void mem_cgroup_put(struct mem_cgroup *memcg)
889 {
890 }
891 
892 static inline struct mem_cgroup *
893 mem_cgroup_iter(struct mem_cgroup *root,
894 		struct mem_cgroup *prev,
895 		struct mem_cgroup_reclaim_cookie *reclaim)
896 {
897 	return NULL;
898 }
899 
900 static inline void mem_cgroup_iter_break(struct mem_cgroup *root,
901 					 struct mem_cgroup *prev)
902 {
903 }
904 
905 static inline int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
906 		int (*fn)(struct task_struct *, void *), void *arg)
907 {
908 	return 0;
909 }
910 
911 static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
912 {
913 	return 0;
914 }
915 
916 static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
917 {
918 	WARN_ON_ONCE(id);
919 	/* XXX: This should always return root_mem_cgroup */
920 	return NULL;
921 }
922 
923 static inline struct mem_cgroup *mem_cgroup_from_seq(struct seq_file *m)
924 {
925 	return NULL;
926 }
927 
928 static inline struct mem_cgroup *lruvec_memcg(struct lruvec *lruvec)
929 {
930 	return NULL;
931 }
932 
933 static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
934 {
935 	return true;
936 }
937 
938 static inline
939 unsigned long mem_cgroup_get_zone_lru_size(struct lruvec *lruvec,
940 		enum lru_list lru, int zone_idx)
941 {
942 	return 0;
943 }
944 
945 static inline unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg)
946 {
947 	return 0;
948 }
949 
950 static inline void
951 mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p)
952 {
953 }
954 
955 static inline void
956 mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg)
957 {
958 }
959 
960 static inline struct mem_cgroup *lock_page_memcg(struct page *page)
961 {
962 	return NULL;
963 }
964 
965 static inline void __unlock_page_memcg(struct mem_cgroup *memcg)
966 {
967 }
968 
969 static inline void unlock_page_memcg(struct page *page)
970 {
971 }
972 
973 static inline void mem_cgroup_handle_over_high(void)
974 {
975 }
976 
977 static inline void mem_cgroup_enter_user_fault(void)
978 {
979 }
980 
981 static inline void mem_cgroup_exit_user_fault(void)
982 {
983 }
984 
985 static inline bool task_in_memcg_oom(struct task_struct *p)
986 {
987 	return false;
988 }
989 
990 static inline bool mem_cgroup_oom_synchronize(bool wait)
991 {
992 	return false;
993 }
994 
995 static inline struct mem_cgroup *mem_cgroup_get_oom_group(
996 	struct task_struct *victim, struct mem_cgroup *oom_domain)
997 {
998 	return NULL;
999 }
1000 
1001 static inline void mem_cgroup_print_oom_group(struct mem_cgroup *memcg)
1002 {
1003 }
1004 
1005 static inline unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx)
1006 {
1007 	return 0;
1008 }
1009 
1010 static inline unsigned long memcg_page_state_local(struct mem_cgroup *memcg,
1011 						   int idx)
1012 {
1013 	return 0;
1014 }
1015 
1016 static inline void __mod_memcg_state(struct mem_cgroup *memcg,
1017 				     int idx,
1018 				     int nr)
1019 {
1020 }
1021 
1022 static inline void mod_memcg_state(struct mem_cgroup *memcg,
1023 				   int idx,
1024 				   int nr)
1025 {
1026 }
1027 
1028 static inline void __mod_memcg_page_state(struct page *page,
1029 					  int idx,
1030 					  int nr)
1031 {
1032 }
1033 
1034 static inline void mod_memcg_page_state(struct page *page,
1035 					int idx,
1036 					int nr)
1037 {
1038 }
1039 
1040 static inline unsigned long lruvec_page_state(struct lruvec *lruvec,
1041 					      enum node_stat_item idx)
1042 {
1043 	return node_page_state(lruvec_pgdat(lruvec), idx);
1044 }
1045 
1046 static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec,
1047 						    enum node_stat_item idx)
1048 {
1049 	return node_page_state(lruvec_pgdat(lruvec), idx);
1050 }
1051 
1052 static inline void __mod_lruvec_state(struct lruvec *lruvec,
1053 				      enum node_stat_item idx, int val)
1054 {
1055 	__mod_node_page_state(lruvec_pgdat(lruvec), idx, val);
1056 }
1057 
1058 static inline void mod_lruvec_state(struct lruvec *lruvec,
1059 				    enum node_stat_item idx, int val)
1060 {
1061 	mod_node_page_state(lruvec_pgdat(lruvec), idx, val);
1062 }
1063 
1064 static inline void __mod_lruvec_page_state(struct page *page,
1065 					   enum node_stat_item idx, int val)
1066 {
1067 	__mod_node_page_state(page_pgdat(page), idx, val);
1068 }
1069 
1070 static inline void mod_lruvec_page_state(struct page *page,
1071 					 enum node_stat_item idx, int val)
1072 {
1073 	mod_node_page_state(page_pgdat(page), idx, val);
1074 }
1075 
1076 static inline void __mod_lruvec_slab_state(void *p, enum node_stat_item idx,
1077 					   int val)
1078 {
1079 	struct page *page = virt_to_head_page(p);
1080 
1081 	__mod_node_page_state(page_pgdat(page), idx, val);
1082 }
1083 
1084 static inline
1085 unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
1086 					    gfp_t gfp_mask,
1087 					    unsigned long *total_scanned)
1088 {
1089 	return 0;
1090 }
1091 
1092 static inline void mem_cgroup_split_huge_fixup(struct page *head)
1093 {
1094 }
1095 
1096 static inline void count_memcg_events(struct mem_cgroup *memcg,
1097 				      enum vm_event_item idx,
1098 				      unsigned long count)
1099 {
1100 }
1101 
1102 static inline void __count_memcg_events(struct mem_cgroup *memcg,
1103 					enum vm_event_item idx,
1104 					unsigned long count)
1105 {
1106 }
1107 
1108 static inline void count_memcg_page_event(struct page *page,
1109 					  int idx)
1110 {
1111 }
1112 
1113 static inline
1114 void count_memcg_event_mm(struct mm_struct *mm, enum vm_event_item idx)
1115 {
1116 }
1117 #endif /* CONFIG_MEMCG */
1118 
1119 /* idx can be of type enum memcg_stat_item or node_stat_item */
1120 static inline void __inc_memcg_state(struct mem_cgroup *memcg,
1121 				     int idx)
1122 {
1123 	__mod_memcg_state(memcg, idx, 1);
1124 }
1125 
1126 /* idx can be of type enum memcg_stat_item or node_stat_item */
1127 static inline void __dec_memcg_state(struct mem_cgroup *memcg,
1128 				     int idx)
1129 {
1130 	__mod_memcg_state(memcg, idx, -1);
1131 }
1132 
1133 /* idx can be of type enum memcg_stat_item or node_stat_item */
1134 static inline void __inc_memcg_page_state(struct page *page,
1135 					  int idx)
1136 {
1137 	__mod_memcg_page_state(page, idx, 1);
1138 }
1139 
1140 /* idx can be of type enum memcg_stat_item or node_stat_item */
1141 static inline void __dec_memcg_page_state(struct page *page,
1142 					  int idx)
1143 {
1144 	__mod_memcg_page_state(page, idx, -1);
1145 }
1146 
1147 static inline void __inc_lruvec_state(struct lruvec *lruvec,
1148 				      enum node_stat_item idx)
1149 {
1150 	__mod_lruvec_state(lruvec, idx, 1);
1151 }
1152 
1153 static inline void __dec_lruvec_state(struct lruvec *lruvec,
1154 				      enum node_stat_item idx)
1155 {
1156 	__mod_lruvec_state(lruvec, idx, -1);
1157 }
1158 
1159 static inline void __inc_lruvec_page_state(struct page *page,
1160 					   enum node_stat_item idx)
1161 {
1162 	__mod_lruvec_page_state(page, idx, 1);
1163 }
1164 
1165 static inline void __dec_lruvec_page_state(struct page *page,
1166 					   enum node_stat_item idx)
1167 {
1168 	__mod_lruvec_page_state(page, idx, -1);
1169 }
1170 
1171 static inline void __inc_lruvec_slab_state(void *p, enum node_stat_item idx)
1172 {
1173 	__mod_lruvec_slab_state(p, idx, 1);
1174 }
1175 
1176 static inline void __dec_lruvec_slab_state(void *p, enum node_stat_item idx)
1177 {
1178 	__mod_lruvec_slab_state(p, idx, -1);
1179 }
1180 
1181 /* idx can be of type enum memcg_stat_item or node_stat_item */
1182 static inline void inc_memcg_state(struct mem_cgroup *memcg,
1183 				   int idx)
1184 {
1185 	mod_memcg_state(memcg, idx, 1);
1186 }
1187 
1188 /* idx can be of type enum memcg_stat_item or node_stat_item */
1189 static inline void dec_memcg_state(struct mem_cgroup *memcg,
1190 				   int idx)
1191 {
1192 	mod_memcg_state(memcg, idx, -1);
1193 }
1194 
1195 /* idx can be of type enum memcg_stat_item or node_stat_item */
1196 static inline void inc_memcg_page_state(struct page *page,
1197 					int idx)
1198 {
1199 	mod_memcg_page_state(page, idx, 1);
1200 }
1201 
1202 /* idx can be of type enum memcg_stat_item or node_stat_item */
1203 static inline void dec_memcg_page_state(struct page *page,
1204 					int idx)
1205 {
1206 	mod_memcg_page_state(page, idx, -1);
1207 }
1208 
1209 static inline void inc_lruvec_state(struct lruvec *lruvec,
1210 				    enum node_stat_item idx)
1211 {
1212 	mod_lruvec_state(lruvec, idx, 1);
1213 }
1214 
1215 static inline void dec_lruvec_state(struct lruvec *lruvec,
1216 				    enum node_stat_item idx)
1217 {
1218 	mod_lruvec_state(lruvec, idx, -1);
1219 }
1220 
1221 static inline void inc_lruvec_page_state(struct page *page,
1222 					 enum node_stat_item idx)
1223 {
1224 	mod_lruvec_page_state(page, idx, 1);
1225 }
1226 
1227 static inline void dec_lruvec_page_state(struct page *page,
1228 					 enum node_stat_item idx)
1229 {
1230 	mod_lruvec_page_state(page, idx, -1);
1231 }
1232 
1233 #ifdef CONFIG_CGROUP_WRITEBACK
1234 
1235 struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb);
1236 void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
1237 			 unsigned long *pheadroom, unsigned long *pdirty,
1238 			 unsigned long *pwriteback);
1239 
1240 #else	/* CONFIG_CGROUP_WRITEBACK */
1241 
1242 static inline struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb)
1243 {
1244 	return NULL;
1245 }
1246 
1247 static inline void mem_cgroup_wb_stats(struct bdi_writeback *wb,
1248 				       unsigned long *pfilepages,
1249 				       unsigned long *pheadroom,
1250 				       unsigned long *pdirty,
1251 				       unsigned long *pwriteback)
1252 {
1253 }
1254 
1255 #endif	/* CONFIG_CGROUP_WRITEBACK */
1256 
1257 struct sock;
1258 bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
1259 void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
1260 #ifdef CONFIG_MEMCG
1261 extern struct static_key_false memcg_sockets_enabled_key;
1262 #define mem_cgroup_sockets_enabled static_branch_unlikely(&memcg_sockets_enabled_key)
1263 void mem_cgroup_sk_alloc(struct sock *sk);
1264 void mem_cgroup_sk_free(struct sock *sk);
1265 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
1266 {
1267 	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_pressure)
1268 		return true;
1269 	do {
1270 		if (time_before(jiffies, memcg->socket_pressure))
1271 			return true;
1272 	} while ((memcg = parent_mem_cgroup(memcg)));
1273 	return false;
1274 }
1275 #else
1276 #define mem_cgroup_sockets_enabled 0
1277 static inline void mem_cgroup_sk_alloc(struct sock *sk) { };
1278 static inline void mem_cgroup_sk_free(struct sock *sk) { };
1279 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
1280 {
1281 	return false;
1282 }
1283 #endif
1284 
1285 struct kmem_cache *memcg_kmem_get_cache(struct kmem_cache *cachep);
1286 void memcg_kmem_put_cache(struct kmem_cache *cachep);
1287 
1288 #ifdef CONFIG_MEMCG_KMEM
1289 int __memcg_kmem_charge(struct page *page, gfp_t gfp, int order);
1290 void __memcg_kmem_uncharge(struct page *page, int order);
1291 int __memcg_kmem_charge_memcg(struct page *page, gfp_t gfp, int order,
1292 			      struct mem_cgroup *memcg);
1293 void __memcg_kmem_uncharge_memcg(struct mem_cgroup *memcg,
1294 				 unsigned int nr_pages);
1295 
1296 extern struct static_key_false memcg_kmem_enabled_key;
1297 extern struct workqueue_struct *memcg_kmem_cache_wq;
1298 
1299 extern int memcg_nr_cache_ids;
1300 void memcg_get_cache_ids(void);
1301 void memcg_put_cache_ids(void);
1302 
1303 /*
1304  * Helper macro to loop through all memcg-specific caches. Callers must still
1305  * check if the cache is valid (it is either valid or NULL).
1306  * the slab_mutex must be held when looping through those caches
1307  */
1308 #define for_each_memcg_cache_index(_idx)	\
1309 	for ((_idx) = 0; (_idx) < memcg_nr_cache_ids; (_idx)++)
1310 
1311 static inline bool memcg_kmem_enabled(void)
1312 {
1313 	return static_branch_unlikely(&memcg_kmem_enabled_key);
1314 }
1315 
1316 static inline int memcg_kmem_charge(struct page *page, gfp_t gfp, int order)
1317 {
1318 	if (memcg_kmem_enabled())
1319 		return __memcg_kmem_charge(page, gfp, order);
1320 	return 0;
1321 }
1322 
1323 static inline void memcg_kmem_uncharge(struct page *page, int order)
1324 {
1325 	if (memcg_kmem_enabled())
1326 		__memcg_kmem_uncharge(page, order);
1327 }
1328 
1329 static inline int memcg_kmem_charge_memcg(struct page *page, gfp_t gfp,
1330 					  int order, struct mem_cgroup *memcg)
1331 {
1332 	if (memcg_kmem_enabled())
1333 		return __memcg_kmem_charge_memcg(page, gfp, order, memcg);
1334 	return 0;
1335 }
1336 
1337 static inline void memcg_kmem_uncharge_memcg(struct page *page, int order,
1338 					     struct mem_cgroup *memcg)
1339 {
1340 	if (memcg_kmem_enabled())
1341 		__memcg_kmem_uncharge_memcg(memcg, 1 << order);
1342 }
1343 
1344 /*
1345  * helper for accessing a memcg's index. It will be used as an index in the
1346  * child cache array in kmem_cache, and also to derive its name. This function
1347  * will return -1 when this is not a kmem-limited memcg.
1348  */
1349 static inline int memcg_cache_id(struct mem_cgroup *memcg)
1350 {
1351 	return memcg ? memcg->kmemcg_id : -1;
1352 }
1353 
1354 extern int memcg_expand_shrinker_maps(int new_id);
1355 
1356 extern void memcg_set_shrinker_bit(struct mem_cgroup *memcg,
1357 				   int nid, int shrinker_id);
1358 #else
1359 
1360 static inline int memcg_kmem_charge(struct page *page, gfp_t gfp, int order)
1361 {
1362 	return 0;
1363 }
1364 
1365 static inline void memcg_kmem_uncharge(struct page *page, int order)
1366 {
1367 }
1368 
1369 static inline int __memcg_kmem_charge(struct page *page, gfp_t gfp, int order)
1370 {
1371 	return 0;
1372 }
1373 
1374 static inline void __memcg_kmem_uncharge(struct page *page, int order)
1375 {
1376 }
1377 
1378 #define for_each_memcg_cache_index(_idx)	\
1379 	for (; NULL; )
1380 
1381 static inline bool memcg_kmem_enabled(void)
1382 {
1383 	return false;
1384 }
1385 
1386 static inline int memcg_cache_id(struct mem_cgroup *memcg)
1387 {
1388 	return -1;
1389 }
1390 
1391 static inline void memcg_get_cache_ids(void)
1392 {
1393 }
1394 
1395 static inline void memcg_put_cache_ids(void)
1396 {
1397 }
1398 
1399 static inline void memcg_set_shrinker_bit(struct mem_cgroup *memcg,
1400 					  int nid, int shrinker_id) { }
1401 #endif /* CONFIG_MEMCG_KMEM */
1402 
1403 #endif /* _LINUX_MEMCONTROL_H */
1404