Commit | Line | Data |
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c942fddf | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
8cdea7c0 BS |
2 | /* memcontrol.c - Memory Controller |
3 | * | |
4 | * Copyright IBM Corporation, 2007 | |
5 | * Author Balbir Singh <balbir@linux.vnet.ibm.com> | |
6 | * | |
78fb7466 PE |
7 | * Copyright 2007 OpenVZ SWsoft Inc |
8 | * Author: Pavel Emelianov <xemul@openvz.org> | |
9 | * | |
2e72b634 KS |
10 | * Memory thresholds |
11 | * Copyright (C) 2009 Nokia Corporation | |
12 | * Author: Kirill A. Shutemov | |
13 | * | |
7ae1e1d0 GC |
14 | * Kernel Memory Controller |
15 | * Copyright (C) 2012 Parallels Inc. and Google Inc. | |
16 | * Authors: Glauber Costa and Suleiman Souhlal | |
17 | * | |
1575e68b JW |
18 | * Native page reclaim |
19 | * Charge lifetime sanitation | |
20 | * Lockless page tracking & accounting | |
21 | * Unified hierarchy configuration model | |
22 | * Copyright (C) 2015 Red Hat, Inc., Johannes Weiner | |
6168d0da AS |
23 | * |
24 | * Per memcg lru locking | |
25 | * Copyright (C) 2020 Alibaba, Inc, Alex Shi | |
8cdea7c0 BS |
26 | */ |
27 | ||
3e32cb2e | 28 | #include <linux/page_counter.h> |
8cdea7c0 BS |
29 | #include <linux/memcontrol.h> |
30 | #include <linux/cgroup.h> | |
a520110e | 31 | #include <linux/pagewalk.h> |
6e84f315 | 32 | #include <linux/sched/mm.h> |
3a4f8a0b | 33 | #include <linux/shmem_fs.h> |
4ffef5fe | 34 | #include <linux/hugetlb.h> |
d13d1443 | 35 | #include <linux/pagemap.h> |
1ff9e6e1 | 36 | #include <linux/vm_event_item.h> |
d52aa412 | 37 | #include <linux/smp.h> |
8a9f3ccd | 38 | #include <linux/page-flags.h> |
66e1707b | 39 | #include <linux/backing-dev.h> |
8a9f3ccd BS |
40 | #include <linux/bit_spinlock.h> |
41 | #include <linux/rcupdate.h> | |
e222432b | 42 | #include <linux/limits.h> |
b9e15baf | 43 | #include <linux/export.h> |
8c7c6e34 | 44 | #include <linux/mutex.h> |
bb4cc1a8 | 45 | #include <linux/rbtree.h> |
b6ac57d5 | 46 | #include <linux/slab.h> |
66e1707b | 47 | #include <linux/swap.h> |
02491447 | 48 | #include <linux/swapops.h> |
66e1707b | 49 | #include <linux/spinlock.h> |
2e72b634 | 50 | #include <linux/eventfd.h> |
79bd9814 | 51 | #include <linux/poll.h> |
2e72b634 | 52 | #include <linux/sort.h> |
66e1707b | 53 | #include <linux/fs.h> |
d2ceb9b7 | 54 | #include <linux/seq_file.h> |
70ddf637 | 55 | #include <linux/vmpressure.h> |
dc90f084 | 56 | #include <linux/memremap.h> |
b69408e8 | 57 | #include <linux/mm_inline.h> |
5d1ea48b | 58 | #include <linux/swap_cgroup.h> |
cdec2e42 | 59 | #include <linux/cpu.h> |
158e0a2d | 60 | #include <linux/oom.h> |
0056f4e6 | 61 | #include <linux/lockdep.h> |
79bd9814 | 62 | #include <linux/file.h> |
03248add | 63 | #include <linux/resume_user_mode.h> |
0e4b01df | 64 | #include <linux/psi.h> |
c8713d0b | 65 | #include <linux/seq_buf.h> |
6a792697 | 66 | #include <linux/sched/isolation.h> |
6011be59 | 67 | #include <linux/kmemleak.h> |
08e552c6 | 68 | #include "internal.h" |
d1a4c0b3 | 69 | #include <net/sock.h> |
4bd2c1ee | 70 | #include <net/ip.h> |
f35c3a8e | 71 | #include "slab.h" |
014bb1de | 72 | #include "swap.h" |
8cdea7c0 | 73 | |
7c0f6ba6 | 74 | #include <linux/uaccess.h> |
8697d331 | 75 | |
cc8e970c KM |
76 | #include <trace/events/vmscan.h> |
77 | ||
073219e9 TH |
78 | struct cgroup_subsys memory_cgrp_subsys __read_mostly; |
79 | EXPORT_SYMBOL(memory_cgrp_subsys); | |
68ae564b | 80 | |
7d828602 JW |
81 | struct mem_cgroup *root_mem_cgroup __read_mostly; |
82 | ||
37d5985c RG |
83 | /* Active memory cgroup to use from an interrupt context */ |
84 | DEFINE_PER_CPU(struct mem_cgroup *, int_active_memcg); | |
c74d40e8 | 85 | EXPORT_PER_CPU_SYMBOL_GPL(int_active_memcg); |
37d5985c | 86 | |
f7e1cb6e | 87 | /* Socket memory accounting disabled? */ |
0f0cace3 | 88 | static bool cgroup_memory_nosocket __ro_after_init; |
f7e1cb6e | 89 | |
04823c83 | 90 | /* Kernel memory accounting disabled? */ |
17c17367 | 91 | static bool cgroup_memory_nokmem __ro_after_init; |
04823c83 | 92 | |
b6c1a8af YS |
93 | /* BPF memory accounting disabled? */ |
94 | static bool cgroup_memory_nobpf __ro_after_init; | |
95 | ||
97b27821 TH |
96 | #ifdef CONFIG_CGROUP_WRITEBACK |
97 | static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq); | |
98 | #endif | |
99 | ||
7941d214 JW |
100 | /* Whether legacy memory+swap accounting is active */ |
101 | static bool do_memsw_account(void) | |
102 | { | |
b25806dc | 103 | return !cgroup_subsys_on_dfl(memory_cgrp_subsys); |
7941d214 JW |
104 | } |
105 | ||
a0db00fc KS |
106 | #define THRESHOLDS_EVENTS_TARGET 128 |
107 | #define SOFTLIMIT_EVENTS_TARGET 1024 | |
e9f8974f | 108 | |
bb4cc1a8 AM |
109 | /* |
110 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
111 | * their hierarchy representation | |
112 | */ | |
113 | ||
ef8f2327 | 114 | struct mem_cgroup_tree_per_node { |
bb4cc1a8 | 115 | struct rb_root rb_root; |
fa90b2fd | 116 | struct rb_node *rb_rightmost; |
bb4cc1a8 AM |
117 | spinlock_t lock; |
118 | }; | |
119 | ||
bb4cc1a8 AM |
120 | struct mem_cgroup_tree { |
121 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
122 | }; | |
123 | ||
124 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
125 | ||
9490ff27 KH |
126 | /* for OOM */ |
127 | struct mem_cgroup_eventfd_list { | |
128 | struct list_head list; | |
129 | struct eventfd_ctx *eventfd; | |
130 | }; | |
2e72b634 | 131 | |
79bd9814 TH |
132 | /* |
133 | * cgroup_event represents events which userspace want to receive. | |
134 | */ | |
3bc942f3 | 135 | struct mem_cgroup_event { |
79bd9814 | 136 | /* |
59b6f873 | 137 | * memcg which the event belongs to. |
79bd9814 | 138 | */ |
59b6f873 | 139 | struct mem_cgroup *memcg; |
79bd9814 TH |
140 | /* |
141 | * eventfd to signal userspace about the event. | |
142 | */ | |
143 | struct eventfd_ctx *eventfd; | |
144 | /* | |
145 | * Each of these stored in a list by the cgroup. | |
146 | */ | |
147 | struct list_head list; | |
fba94807 TH |
148 | /* |
149 | * register_event() callback will be used to add new userspace | |
150 | * waiter for changes related to this event. Use eventfd_signal() | |
151 | * on eventfd to send notification to userspace. | |
152 | */ | |
59b6f873 | 153 | int (*register_event)(struct mem_cgroup *memcg, |
347c4a87 | 154 | struct eventfd_ctx *eventfd, const char *args); |
fba94807 TH |
155 | /* |
156 | * unregister_event() callback will be called when userspace closes | |
157 | * the eventfd or on cgroup removing. This callback must be set, | |
158 | * if you want provide notification functionality. | |
159 | */ | |
59b6f873 | 160 | void (*unregister_event)(struct mem_cgroup *memcg, |
fba94807 | 161 | struct eventfd_ctx *eventfd); |
79bd9814 TH |
162 | /* |
163 | * All fields below needed to unregister event when | |
164 | * userspace closes eventfd. | |
165 | */ | |
166 | poll_table pt; | |
167 | wait_queue_head_t *wqh; | |
ac6424b9 | 168 | wait_queue_entry_t wait; |
79bd9814 TH |
169 | struct work_struct remove; |
170 | }; | |
171 | ||
c0ff4b85 R |
172 | static void mem_cgroup_threshold(struct mem_cgroup *memcg); |
173 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); | |
2e72b634 | 174 | |
7dc74be0 DN |
175 | /* Stuffs for move charges at task migration. */ |
176 | /* | |
1dfab5ab | 177 | * Types of charges to be moved. |
7dc74be0 | 178 | */ |
1dfab5ab JW |
179 | #define MOVE_ANON 0x1U |
180 | #define MOVE_FILE 0x2U | |
181 | #define MOVE_MASK (MOVE_ANON | MOVE_FILE) | |
7dc74be0 | 182 | |
4ffef5fe DN |
183 | /* "mc" and its members are protected by cgroup_mutex */ |
184 | static struct move_charge_struct { | |
b1dd693e | 185 | spinlock_t lock; /* for from, to */ |
264a0ae1 | 186 | struct mm_struct *mm; |
4ffef5fe DN |
187 | struct mem_cgroup *from; |
188 | struct mem_cgroup *to; | |
1dfab5ab | 189 | unsigned long flags; |
4ffef5fe | 190 | unsigned long precharge; |
854ffa8d | 191 | unsigned long moved_charge; |
483c30b5 | 192 | unsigned long moved_swap; |
8033b97c DN |
193 | struct task_struct *moving_task; /* a task moving charges */ |
194 | wait_queue_head_t waitq; /* a waitq for other context */ | |
195 | } mc = { | |
2bd9bb20 | 196 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
197 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
198 | }; | |
4ffef5fe | 199 | |
4e416953 | 200 | /* |
f4d005af | 201 | * Maximum loops in mem_cgroup_soft_reclaim(), used for soft |
4e416953 BS |
202 | * limit reclaim to prevent infinite loops, if they ever occur. |
203 | */ | |
a0db00fc | 204 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS 100 |
bb4cc1a8 | 205 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS 2 |
4e416953 | 206 | |
8c7c6e34 | 207 | /* for encoding cft->private value on file */ |
86ae53e1 GC |
208 | enum res_type { |
209 | _MEM, | |
210 | _MEMSWAP, | |
510fc4e1 | 211 | _KMEM, |
d55f90bf | 212 | _TCP, |
86ae53e1 GC |
213 | }; |
214 | ||
a0db00fc KS |
215 | #define MEMFILE_PRIVATE(x, val) ((x) << 16 | (val)) |
216 | #define MEMFILE_TYPE(val) ((val) >> 16 & 0xffff) | |
8c7c6e34 KH |
217 | #define MEMFILE_ATTR(val) ((val) & 0xffff) |
218 | ||
b05706f1 KT |
219 | /* |
220 | * Iteration constructs for visiting all cgroups (under a tree). If | |
221 | * loops are exited prematurely (break), mem_cgroup_iter_break() must | |
222 | * be used for reference counting. | |
223 | */ | |
224 | #define for_each_mem_cgroup_tree(iter, root) \ | |
225 | for (iter = mem_cgroup_iter(root, NULL, NULL); \ | |
226 | iter != NULL; \ | |
227 | iter = mem_cgroup_iter(root, iter, NULL)) | |
228 | ||
229 | #define for_each_mem_cgroup(iter) \ | |
230 | for (iter = mem_cgroup_iter(NULL, NULL, NULL); \ | |
231 | iter != NULL; \ | |
232 | iter = mem_cgroup_iter(NULL, iter, NULL)) | |
233 | ||
a4ebf1b6 | 234 | static inline bool task_is_dying(void) |
7775face TH |
235 | { |
236 | return tsk_is_oom_victim(current) || fatal_signal_pending(current) || | |
237 | (current->flags & PF_EXITING); | |
238 | } | |
239 | ||
70ddf637 AV |
240 | /* Some nice accessors for the vmpressure. */ |
241 | struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg) | |
242 | { | |
243 | if (!memcg) | |
244 | memcg = root_mem_cgroup; | |
245 | return &memcg->vmpressure; | |
246 | } | |
247 | ||
9647875b | 248 | struct mem_cgroup *vmpressure_to_memcg(struct vmpressure *vmpr) |
70ddf637 | 249 | { |
9647875b | 250 | return container_of(vmpr, struct mem_cgroup, vmpressure); |
70ddf637 AV |
251 | } |
252 | ||
1aacbd35 RG |
253 | #define CURRENT_OBJCG_UPDATE_BIT 0 |
254 | #define CURRENT_OBJCG_UPDATE_FLAG (1UL << CURRENT_OBJCG_UPDATE_BIT) | |
255 | ||
84c07d11 | 256 | #ifdef CONFIG_MEMCG_KMEM |
0764db9b | 257 | static DEFINE_SPINLOCK(objcg_lock); |
bf4f0599 | 258 | |
4d5c8aed RG |
259 | bool mem_cgroup_kmem_disabled(void) |
260 | { | |
261 | return cgroup_memory_nokmem; | |
262 | } | |
263 | ||
f1286fae MS |
264 | static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, |
265 | unsigned int nr_pages); | |
c1a660de | 266 | |
bf4f0599 RG |
267 | static void obj_cgroup_release(struct percpu_ref *ref) |
268 | { | |
269 | struct obj_cgroup *objcg = container_of(ref, struct obj_cgroup, refcnt); | |
bf4f0599 RG |
270 | unsigned int nr_bytes; |
271 | unsigned int nr_pages; | |
272 | unsigned long flags; | |
273 | ||
274 | /* | |
275 | * At this point all allocated objects are freed, and | |
276 | * objcg->nr_charged_bytes can't have an arbitrary byte value. | |
277 | * However, it can be PAGE_SIZE or (x * PAGE_SIZE). | |
278 | * | |
279 | * The following sequence can lead to it: | |
280 | * 1) CPU0: objcg == stock->cached_objcg | |
281 | * 2) CPU1: we do a small allocation (e.g. 92 bytes), | |
282 | * PAGE_SIZE bytes are charged | |
283 | * 3) CPU1: a process from another memcg is allocating something, | |
284 | * the stock if flushed, | |
285 | * objcg->nr_charged_bytes = PAGE_SIZE - 92 | |
286 | * 5) CPU0: we do release this object, | |
287 | * 92 bytes are added to stock->nr_bytes | |
288 | * 6) CPU0: stock is flushed, | |
289 | * 92 bytes are added to objcg->nr_charged_bytes | |
290 | * | |
291 | * In the result, nr_charged_bytes == PAGE_SIZE. | |
292 | * This page will be uncharged in obj_cgroup_release(). | |
293 | */ | |
294 | nr_bytes = atomic_read(&objcg->nr_charged_bytes); | |
295 | WARN_ON_ONCE(nr_bytes & (PAGE_SIZE - 1)); | |
296 | nr_pages = nr_bytes >> PAGE_SHIFT; | |
297 | ||
bf4f0599 | 298 | if (nr_pages) |
f1286fae | 299 | obj_cgroup_uncharge_pages(objcg, nr_pages); |
271dd6b1 | 300 | |
0764db9b | 301 | spin_lock_irqsave(&objcg_lock, flags); |
bf4f0599 | 302 | list_del(&objcg->list); |
0764db9b | 303 | spin_unlock_irqrestore(&objcg_lock, flags); |
bf4f0599 RG |
304 | |
305 | percpu_ref_exit(ref); | |
306 | kfree_rcu(objcg, rcu); | |
307 | } | |
308 | ||
309 | static struct obj_cgroup *obj_cgroup_alloc(void) | |
310 | { | |
311 | struct obj_cgroup *objcg; | |
312 | int ret; | |
313 | ||
314 | objcg = kzalloc(sizeof(struct obj_cgroup), GFP_KERNEL); | |
315 | if (!objcg) | |
316 | return NULL; | |
317 | ||
318 | ret = percpu_ref_init(&objcg->refcnt, obj_cgroup_release, 0, | |
319 | GFP_KERNEL); | |
320 | if (ret) { | |
321 | kfree(objcg); | |
322 | return NULL; | |
323 | } | |
324 | INIT_LIST_HEAD(&objcg->list); | |
325 | return objcg; | |
326 | } | |
327 | ||
328 | static void memcg_reparent_objcgs(struct mem_cgroup *memcg, | |
329 | struct mem_cgroup *parent) | |
330 | { | |
331 | struct obj_cgroup *objcg, *iter; | |
332 | ||
333 | objcg = rcu_replace_pointer(memcg->objcg, NULL, true); | |
334 | ||
0764db9b | 335 | spin_lock_irq(&objcg_lock); |
bf4f0599 | 336 | |
9838354e MS |
337 | /* 1) Ready to reparent active objcg. */ |
338 | list_add(&objcg->list, &memcg->objcg_list); | |
339 | /* 2) Reparent active objcg and already reparented objcgs to parent. */ | |
340 | list_for_each_entry(iter, &memcg->objcg_list, list) | |
341 | WRITE_ONCE(iter->memcg, parent); | |
342 | /* 3) Move already reparented objcgs to the parent's list */ | |
bf4f0599 RG |
343 | list_splice(&memcg->objcg_list, &parent->objcg_list); |
344 | ||
0764db9b | 345 | spin_unlock_irq(&objcg_lock); |
bf4f0599 RG |
346 | |
347 | percpu_ref_kill(&objcg->refcnt); | |
348 | } | |
349 | ||
d7f25f8a GC |
350 | /* |
351 | * A lot of the calls to the cache allocation functions are expected to be | |
272911a4 | 352 | * inlined by the compiler. Since the calls to memcg_slab_pre_alloc_hook() are |
d7f25f8a GC |
353 | * conditional to this static branch, we'll have to allow modules that does |
354 | * kmem_cache_alloc and the such to see this symbol as well | |
355 | */ | |
f7a449f7 RG |
356 | DEFINE_STATIC_KEY_FALSE(memcg_kmem_online_key); |
357 | EXPORT_SYMBOL(memcg_kmem_online_key); | |
b6c1a8af YS |
358 | |
359 | DEFINE_STATIC_KEY_FALSE(memcg_bpf_enabled_key); | |
360 | EXPORT_SYMBOL(memcg_bpf_enabled_key); | |
0a432dcb | 361 | #endif |
17cc4dfe | 362 | |
ad7fa852 | 363 | /** |
75376c6f MWO |
364 | * mem_cgroup_css_from_folio - css of the memcg associated with a folio |
365 | * @folio: folio of interest | |
ad7fa852 TH |
366 | * |
367 | * If memcg is bound to the default hierarchy, css of the memcg associated | |
75376c6f | 368 | * with @folio is returned. The returned css remains associated with @folio |
ad7fa852 TH |
369 | * until it is released. |
370 | * | |
371 | * If memcg is bound to a traditional hierarchy, the css of root_mem_cgroup | |
372 | * is returned. | |
ad7fa852 | 373 | */ |
75376c6f | 374 | struct cgroup_subsys_state *mem_cgroup_css_from_folio(struct folio *folio) |
ad7fa852 | 375 | { |
75376c6f | 376 | struct mem_cgroup *memcg = folio_memcg(folio); |
ad7fa852 | 377 | |
9e10a130 | 378 | if (!memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
ad7fa852 TH |
379 | memcg = root_mem_cgroup; |
380 | ||
ad7fa852 TH |
381 | return &memcg->css; |
382 | } | |
383 | ||
2fc04524 VD |
384 | /** |
385 | * page_cgroup_ino - return inode number of the memcg a page is charged to | |
386 | * @page: the page | |
387 | * | |
388 | * Look up the closest online ancestor of the memory cgroup @page is charged to | |
389 | * and return its inode number or 0 if @page is not charged to any cgroup. It | |
390 | * is safe to call this function without holding a reference to @page. | |
391 | * | |
392 | * Note, this function is inherently racy, because there is nothing to prevent | |
393 | * the cgroup inode from getting torn down and potentially reallocated a moment | |
394 | * after page_cgroup_ino() returns, so it only should be used by callers that | |
395 | * do not care (such as procfs interfaces). | |
396 | */ | |
397 | ino_t page_cgroup_ino(struct page *page) | |
398 | { | |
399 | struct mem_cgroup *memcg; | |
400 | unsigned long ino = 0; | |
401 | ||
402 | rcu_read_lock(); | |
ec342603 YA |
403 | /* page_folio() is racy here, but the entire function is racy anyway */ |
404 | memcg = folio_memcg_check(page_folio(page)); | |
286e04b8 | 405 | |
2fc04524 VD |
406 | while (memcg && !(memcg->css.flags & CSS_ONLINE)) |
407 | memcg = parent_mem_cgroup(memcg); | |
408 | if (memcg) | |
409 | ino = cgroup_ino(memcg->css.cgroup); | |
410 | rcu_read_unlock(); | |
411 | return ino; | |
412 | } | |
413 | ||
ef8f2327 MG |
414 | static void __mem_cgroup_insert_exceeded(struct mem_cgroup_per_node *mz, |
415 | struct mem_cgroup_tree_per_node *mctz, | |
3e32cb2e | 416 | unsigned long new_usage_in_excess) |
bb4cc1a8 AM |
417 | { |
418 | struct rb_node **p = &mctz->rb_root.rb_node; | |
419 | struct rb_node *parent = NULL; | |
ef8f2327 | 420 | struct mem_cgroup_per_node *mz_node; |
fa90b2fd | 421 | bool rightmost = true; |
bb4cc1a8 AM |
422 | |
423 | if (mz->on_tree) | |
424 | return; | |
425 | ||
426 | mz->usage_in_excess = new_usage_in_excess; | |
427 | if (!mz->usage_in_excess) | |
428 | return; | |
429 | while (*p) { | |
430 | parent = *p; | |
ef8f2327 | 431 | mz_node = rb_entry(parent, struct mem_cgroup_per_node, |
bb4cc1a8 | 432 | tree_node); |
fa90b2fd | 433 | if (mz->usage_in_excess < mz_node->usage_in_excess) { |
bb4cc1a8 | 434 | p = &(*p)->rb_left; |
fa90b2fd | 435 | rightmost = false; |
378876b0 | 436 | } else { |
bb4cc1a8 | 437 | p = &(*p)->rb_right; |
378876b0 | 438 | } |
bb4cc1a8 | 439 | } |
fa90b2fd DB |
440 | |
441 | if (rightmost) | |
442 | mctz->rb_rightmost = &mz->tree_node; | |
443 | ||
bb4cc1a8 AM |
444 | rb_link_node(&mz->tree_node, parent, p); |
445 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
446 | mz->on_tree = true; | |
447 | } | |
448 | ||
ef8f2327 MG |
449 | static void __mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz, |
450 | struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 AM |
451 | { |
452 | if (!mz->on_tree) | |
453 | return; | |
fa90b2fd DB |
454 | |
455 | if (&mz->tree_node == mctz->rb_rightmost) | |
456 | mctz->rb_rightmost = rb_prev(&mz->tree_node); | |
457 | ||
bb4cc1a8 AM |
458 | rb_erase(&mz->tree_node, &mctz->rb_root); |
459 | mz->on_tree = false; | |
460 | } | |
461 | ||
ef8f2327 MG |
462 | static void mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz, |
463 | struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 464 | { |
0a31bc97 JW |
465 | unsigned long flags; |
466 | ||
467 | spin_lock_irqsave(&mctz->lock, flags); | |
cf2c8127 | 468 | __mem_cgroup_remove_exceeded(mz, mctz); |
0a31bc97 | 469 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
470 | } |
471 | ||
3e32cb2e JW |
472 | static unsigned long soft_limit_excess(struct mem_cgroup *memcg) |
473 | { | |
474 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
4db0c3c2 | 475 | unsigned long soft_limit = READ_ONCE(memcg->soft_limit); |
3e32cb2e JW |
476 | unsigned long excess = 0; |
477 | ||
478 | if (nr_pages > soft_limit) | |
479 | excess = nr_pages - soft_limit; | |
480 | ||
481 | return excess; | |
482 | } | |
bb4cc1a8 | 483 | |
658b69c9 | 484 | static void mem_cgroup_update_tree(struct mem_cgroup *memcg, int nid) |
bb4cc1a8 | 485 | { |
3e32cb2e | 486 | unsigned long excess; |
ef8f2327 MG |
487 | struct mem_cgroup_per_node *mz; |
488 | struct mem_cgroup_tree_per_node *mctz; | |
bb4cc1a8 | 489 | |
e4dde56c | 490 | if (lru_gen_enabled()) { |
36c7b4db | 491 | if (soft_limit_excess(memcg)) |
5c7e7a0d | 492 | lru_gen_soft_reclaim(memcg, nid); |
e4dde56c YZ |
493 | return; |
494 | } | |
495 | ||
2ab082ba | 496 | mctz = soft_limit_tree.rb_tree_per_node[nid]; |
bfc7228b LD |
497 | if (!mctz) |
498 | return; | |
bb4cc1a8 AM |
499 | /* |
500 | * Necessary to update all ancestors when hierarchy is used. | |
501 | * because their event counter is not touched. | |
502 | */ | |
503 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
658b69c9 | 504 | mz = memcg->nodeinfo[nid]; |
3e32cb2e | 505 | excess = soft_limit_excess(memcg); |
bb4cc1a8 AM |
506 | /* |
507 | * We have to update the tree if mz is on RB-tree or | |
508 | * mem is over its softlimit. | |
509 | */ | |
510 | if (excess || mz->on_tree) { | |
0a31bc97 JW |
511 | unsigned long flags; |
512 | ||
513 | spin_lock_irqsave(&mctz->lock, flags); | |
bb4cc1a8 AM |
514 | /* if on-tree, remove it */ |
515 | if (mz->on_tree) | |
cf2c8127 | 516 | __mem_cgroup_remove_exceeded(mz, mctz); |
bb4cc1a8 AM |
517 | /* |
518 | * Insert again. mz->usage_in_excess will be updated. | |
519 | * If excess is 0, no tree ops. | |
520 | */ | |
cf2c8127 | 521 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 522 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
523 | } |
524 | } | |
525 | } | |
526 | ||
527 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) | |
528 | { | |
ef8f2327 MG |
529 | struct mem_cgroup_tree_per_node *mctz; |
530 | struct mem_cgroup_per_node *mz; | |
531 | int nid; | |
bb4cc1a8 | 532 | |
e231875b | 533 | for_each_node(nid) { |
a3747b53 | 534 | mz = memcg->nodeinfo[nid]; |
2ab082ba | 535 | mctz = soft_limit_tree.rb_tree_per_node[nid]; |
bfc7228b LD |
536 | if (mctz) |
537 | mem_cgroup_remove_exceeded(mz, mctz); | |
bb4cc1a8 AM |
538 | } |
539 | } | |
540 | ||
ef8f2327 MG |
541 | static struct mem_cgroup_per_node * |
542 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 543 | { |
ef8f2327 | 544 | struct mem_cgroup_per_node *mz; |
bb4cc1a8 AM |
545 | |
546 | retry: | |
547 | mz = NULL; | |
fa90b2fd | 548 | if (!mctz->rb_rightmost) |
bb4cc1a8 AM |
549 | goto done; /* Nothing to reclaim from */ |
550 | ||
fa90b2fd DB |
551 | mz = rb_entry(mctz->rb_rightmost, |
552 | struct mem_cgroup_per_node, tree_node); | |
bb4cc1a8 AM |
553 | /* |
554 | * Remove the node now but someone else can add it back, | |
555 | * we will to add it back at the end of reclaim to its correct | |
556 | * position in the tree. | |
557 | */ | |
cf2c8127 | 558 | __mem_cgroup_remove_exceeded(mz, mctz); |
3e32cb2e | 559 | if (!soft_limit_excess(mz->memcg) || |
8965aa28 | 560 | !css_tryget(&mz->memcg->css)) |
bb4cc1a8 AM |
561 | goto retry; |
562 | done: | |
563 | return mz; | |
564 | } | |
565 | ||
ef8f2327 MG |
566 | static struct mem_cgroup_per_node * |
567 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 568 | { |
ef8f2327 | 569 | struct mem_cgroup_per_node *mz; |
bb4cc1a8 | 570 | |
0a31bc97 | 571 | spin_lock_irq(&mctz->lock); |
bb4cc1a8 | 572 | mz = __mem_cgroup_largest_soft_limit_node(mctz); |
0a31bc97 | 573 | spin_unlock_irq(&mctz->lock); |
bb4cc1a8 AM |
574 | return mz; |
575 | } | |
576 | ||
d396def5 SB |
577 | /* Subset of vm_event_item to report for memcg event stats */ |
578 | static const unsigned int memcg_vm_event_stat[] = { | |
8278f1c7 SB |
579 | PGPGIN, |
580 | PGPGOUT, | |
d396def5 SB |
581 | PGSCAN_KSWAPD, |
582 | PGSCAN_DIRECT, | |
57e9cc50 | 583 | PGSCAN_KHUGEPAGED, |
d396def5 SB |
584 | PGSTEAL_KSWAPD, |
585 | PGSTEAL_DIRECT, | |
57e9cc50 | 586 | PGSTEAL_KHUGEPAGED, |
d396def5 SB |
587 | PGFAULT, |
588 | PGMAJFAULT, | |
589 | PGREFILL, | |
590 | PGACTIVATE, | |
591 | PGDEACTIVATE, | |
592 | PGLAZYFREE, | |
593 | PGLAZYFREED, | |
594 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) | |
595 | ZSWPIN, | |
596 | ZSWPOUT, | |
e0bf1dc8 | 597 | ZSWPWB, |
d396def5 SB |
598 | #endif |
599 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
600 | THP_FAULT_ALLOC, | |
601 | THP_COLLAPSE_ALLOC, | |
811244a5 XH |
602 | THP_SWPOUT, |
603 | THP_SWPOUT_FALLBACK, | |
d396def5 SB |
604 | #endif |
605 | }; | |
606 | ||
8278f1c7 SB |
607 | #define NR_MEMCG_EVENTS ARRAY_SIZE(memcg_vm_event_stat) |
608 | static int mem_cgroup_events_index[NR_VM_EVENT_ITEMS] __read_mostly; | |
609 | ||
610 | static void init_memcg_events(void) | |
611 | { | |
612 | int i; | |
613 | ||
614 | for (i = 0; i < NR_MEMCG_EVENTS; ++i) | |
615 | mem_cgroup_events_index[memcg_vm_event_stat[i]] = i + 1; | |
616 | } | |
617 | ||
618 | static inline int memcg_events_index(enum vm_event_item idx) | |
619 | { | |
620 | return mem_cgroup_events_index[idx] - 1; | |
621 | } | |
622 | ||
410f8e82 SB |
623 | struct memcg_vmstats_percpu { |
624 | /* Local (CPU and cgroup) page state & events */ | |
625 | long state[MEMCG_NR_STAT]; | |
8278f1c7 | 626 | unsigned long events[NR_MEMCG_EVENTS]; |
410f8e82 SB |
627 | |
628 | /* Delta calculation for lockless upward propagation */ | |
629 | long state_prev[MEMCG_NR_STAT]; | |
8278f1c7 | 630 | unsigned long events_prev[NR_MEMCG_EVENTS]; |
410f8e82 SB |
631 | |
632 | /* Cgroup1: threshold notifications & softlimit tree updates */ | |
633 | unsigned long nr_page_events; | |
634 | unsigned long targets[MEM_CGROUP_NTARGETS]; | |
8d59d221 YA |
635 | |
636 | /* Stats updates since the last flush */ | |
637 | unsigned int stats_updates; | |
410f8e82 SB |
638 | }; |
639 | ||
640 | struct memcg_vmstats { | |
641 | /* Aggregated (CPU and subtree) page state & events */ | |
642 | long state[MEMCG_NR_STAT]; | |
8278f1c7 | 643 | unsigned long events[NR_MEMCG_EVENTS]; |
410f8e82 | 644 | |
f82e6bf9 YA |
645 | /* Non-hierarchical (CPU aggregated) page state & events */ |
646 | long state_local[MEMCG_NR_STAT]; | |
647 | unsigned long events_local[NR_MEMCG_EVENTS]; | |
648 | ||
410f8e82 SB |
649 | /* Pending child counts during tree propagation */ |
650 | long state_pending[MEMCG_NR_STAT]; | |
8278f1c7 | 651 | unsigned long events_pending[NR_MEMCG_EVENTS]; |
8d59d221 YA |
652 | |
653 | /* Stats updates since the last flush */ | |
654 | atomic64_t stats_updates; | |
410f8e82 SB |
655 | }; |
656 | ||
11192d9c SB |
657 | /* |
658 | * memcg and lruvec stats flushing | |
659 | * | |
660 | * Many codepaths leading to stats update or read are performance sensitive and | |
661 | * adding stats flushing in such codepaths is not desirable. So, to optimize the | |
662 | * flushing the kernel does: | |
663 | * | |
664 | * 1) Periodically and asynchronously flush the stats every 2 seconds to not let | |
665 | * rstat update tree grow unbounded. | |
666 | * | |
667 | * 2) Flush the stats synchronously on reader side only when there are more than | |
668 | * (MEMCG_CHARGE_BATCH * nr_cpus) update events. Though this optimization | |
669 | * will let stats be out of sync by atmost (MEMCG_CHARGE_BATCH * nr_cpus) but | |
670 | * only for 2 seconds due to (1). | |
671 | */ | |
672 | static void flush_memcg_stats_dwork(struct work_struct *w); | |
673 | static DECLARE_DEFERRABLE_WORK(stats_flush_dwork, flush_memcg_stats_dwork); | |
508bed88 | 674 | static u64 flush_last_time; |
9b301615 SB |
675 | |
676 | #define FLUSH_TIME (2UL*HZ) | |
11192d9c | 677 | |
be3e67b5 SAS |
678 | /* |
679 | * Accessors to ensure that preemption is disabled on PREEMPT_RT because it can | |
680 | * not rely on this as part of an acquired spinlock_t lock. These functions are | |
681 | * never used in hardirq context on PREEMPT_RT and therefore disabling preemtion | |
682 | * is sufficient. | |
683 | */ | |
684 | static void memcg_stats_lock(void) | |
685 | { | |
e575d401 TG |
686 | preempt_disable_nested(); |
687 | VM_WARN_ON_IRQS_ENABLED(); | |
be3e67b5 SAS |
688 | } |
689 | ||
690 | static void __memcg_stats_lock(void) | |
691 | { | |
e575d401 | 692 | preempt_disable_nested(); |
be3e67b5 SAS |
693 | } |
694 | ||
695 | static void memcg_stats_unlock(void) | |
696 | { | |
e575d401 | 697 | preempt_enable_nested(); |
be3e67b5 SAS |
698 | } |
699 | ||
8d59d221 YA |
700 | |
701 | static bool memcg_should_flush_stats(struct mem_cgroup *memcg) | |
702 | { | |
703 | return atomic64_read(&memcg->vmstats->stats_updates) > | |
704 | MEMCG_CHARGE_BATCH * num_online_cpus(); | |
705 | } | |
706 | ||
5b3be698 | 707 | static inline void memcg_rstat_updated(struct mem_cgroup *memcg, int val) |
11192d9c | 708 | { |
8d59d221 | 709 | int cpu = smp_processor_id(); |
5b3be698 SB |
710 | unsigned int x; |
711 | ||
f9d911ca YA |
712 | if (!val) |
713 | return; | |
714 | ||
8d59d221 YA |
715 | cgroup_rstat_updated(memcg->css.cgroup, cpu); |
716 | ||
717 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
718 | x = __this_cpu_add_return(memcg->vmstats_percpu->stats_updates, | |
719 | abs(val)); | |
720 | ||
721 | if (x < MEMCG_CHARGE_BATCH) | |
722 | continue; | |
5b3be698 | 723 | |
873f64b7 | 724 | /* |
8d59d221 YA |
725 | * If @memcg is already flush-able, increasing stats_updates is |
726 | * redundant. Avoid the overhead of the atomic update. | |
873f64b7 | 727 | */ |
8d59d221 YA |
728 | if (!memcg_should_flush_stats(memcg)) |
729 | atomic64_add(x, &memcg->vmstats->stats_updates); | |
730 | __this_cpu_write(memcg->vmstats_percpu->stats_updates, 0); | |
5b3be698 | 731 | } |
11192d9c SB |
732 | } |
733 | ||
7d7ef0a4 | 734 | static void do_flush_stats(struct mem_cgroup *memcg) |
11192d9c | 735 | { |
7d7ef0a4 YA |
736 | if (mem_cgroup_is_root(memcg)) |
737 | WRITE_ONCE(flush_last_time, jiffies_64); | |
9fad9aee | 738 | |
7d7ef0a4 | 739 | cgroup_rstat_flush(memcg->css.cgroup); |
11192d9c SB |
740 | } |
741 | ||
7d7ef0a4 YA |
742 | /* |
743 | * mem_cgroup_flush_stats - flush the stats of a memory cgroup subtree | |
744 | * @memcg: root of the subtree to flush | |
745 | * | |
746 | * Flushing is serialized by the underlying global rstat lock. There is also a | |
747 | * minimum amount of work to be done even if there are no stat updates to flush. | |
748 | * Hence, we only flush the stats if the updates delta exceeds a threshold. This | |
749 | * avoids unnecessary work and contention on the underlying lock. | |
750 | */ | |
751 | void mem_cgroup_flush_stats(struct mem_cgroup *memcg) | |
11192d9c | 752 | { |
7d7ef0a4 YA |
753 | if (mem_cgroup_disabled()) |
754 | return; | |
755 | ||
756 | if (!memcg) | |
757 | memcg = root_mem_cgroup; | |
758 | ||
759 | if (memcg_should_flush_stats(memcg)) | |
760 | do_flush_stats(memcg); | |
9fad9aee YA |
761 | } |
762 | ||
7d7ef0a4 | 763 | void mem_cgroup_flush_stats_ratelimited(struct mem_cgroup *memcg) |
9b301615 | 764 | { |
508bed88 YA |
765 | /* Only flush if the periodic flusher is one full cycle late */ |
766 | if (time_after64(jiffies_64, READ_ONCE(flush_last_time) + 2*FLUSH_TIME)) | |
7d7ef0a4 | 767 | mem_cgroup_flush_stats(memcg); |
9b301615 SB |
768 | } |
769 | ||
11192d9c SB |
770 | static void flush_memcg_stats_dwork(struct work_struct *w) |
771 | { | |
9fad9aee | 772 | /* |
8d59d221 YA |
773 | * Deliberately ignore memcg_should_flush_stats() here so that flushing |
774 | * in latency-sensitive paths is as cheap as possible. | |
9fad9aee | 775 | */ |
7d7ef0a4 | 776 | do_flush_stats(root_mem_cgroup); |
9b301615 | 777 | queue_delayed_work(system_unbound_wq, &stats_flush_dwork, FLUSH_TIME); |
11192d9c SB |
778 | } |
779 | ||
410f8e82 SB |
780 | unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx) |
781 | { | |
782 | long x = READ_ONCE(memcg->vmstats->state[idx]); | |
783 | #ifdef CONFIG_SMP | |
784 | if (x < 0) | |
785 | x = 0; | |
786 | #endif | |
787 | return x; | |
788 | } | |
789 | ||
7bd5bc3c YA |
790 | static int memcg_page_state_unit(int item); |
791 | ||
792 | /* | |
793 | * Normalize the value passed into memcg_rstat_updated() to be in pages. Round | |
794 | * up non-zero sub-page updates to 1 page as zero page updates are ignored. | |
795 | */ | |
796 | static int memcg_state_val_in_pages(int idx, int val) | |
797 | { | |
798 | int unit = memcg_page_state_unit(idx); | |
799 | ||
800 | if (!val || unit == PAGE_SIZE) | |
801 | return val; | |
802 | else | |
803 | return max(val * unit / PAGE_SIZE, 1UL); | |
804 | } | |
805 | ||
db9adbcb JW |
806 | /** |
807 | * __mod_memcg_state - update cgroup memory statistics | |
808 | * @memcg: the memory cgroup | |
809 | * @idx: the stat item - can be enum memcg_stat_item or enum node_stat_item | |
810 | * @val: delta to add to the counter, can be negative | |
811 | */ | |
812 | void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val) | |
813 | { | |
db9adbcb JW |
814 | if (mem_cgroup_disabled()) |
815 | return; | |
816 | ||
2d146aa3 | 817 | __this_cpu_add(memcg->vmstats_percpu->state[idx], val); |
7bd5bc3c | 818 | memcg_rstat_updated(memcg, memcg_state_val_in_pages(idx, val)); |
db9adbcb JW |
819 | } |
820 | ||
2d146aa3 | 821 | /* idx can be of type enum memcg_stat_item or node_stat_item. */ |
a18e6e6e JW |
822 | static unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx) |
823 | { | |
f82e6bf9 | 824 | long x = READ_ONCE(memcg->vmstats->state_local[idx]); |
a18e6e6e | 825 | |
a18e6e6e JW |
826 | #ifdef CONFIG_SMP |
827 | if (x < 0) | |
828 | x = 0; | |
829 | #endif | |
830 | return x; | |
831 | } | |
832 | ||
eedc4e5a RG |
833 | void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, |
834 | int val) | |
db9adbcb JW |
835 | { |
836 | struct mem_cgroup_per_node *pn; | |
42a30035 | 837 | struct mem_cgroup *memcg; |
db9adbcb | 838 | |
db9adbcb | 839 | pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec); |
42a30035 | 840 | memcg = pn->memcg; |
db9adbcb | 841 | |
be3e67b5 | 842 | /* |
be16dd76 | 843 | * The caller from rmap relies on disabled preemption because they never |
be3e67b5 SAS |
844 | * update their counter from in-interrupt context. For these two |
845 | * counters we check that the update is never performed from an | |
846 | * interrupt context while other caller need to have disabled interrupt. | |
847 | */ | |
848 | __memcg_stats_lock(); | |
e575d401 | 849 | if (IS_ENABLED(CONFIG_DEBUG_VM)) { |
be3e67b5 SAS |
850 | switch (idx) { |
851 | case NR_ANON_MAPPED: | |
852 | case NR_FILE_MAPPED: | |
853 | case NR_ANON_THPS: | |
854 | case NR_SHMEM_PMDMAPPED: | |
855 | case NR_FILE_PMDMAPPED: | |
856 | WARN_ON_ONCE(!in_task()); | |
857 | break; | |
858 | default: | |
e575d401 | 859 | VM_WARN_ON_IRQS_ENABLED(); |
be3e67b5 SAS |
860 | } |
861 | } | |
862 | ||
db9adbcb | 863 | /* Update memcg */ |
11192d9c | 864 | __this_cpu_add(memcg->vmstats_percpu->state[idx], val); |
db9adbcb | 865 | |
b4c46484 | 866 | /* Update lruvec */ |
7e1c0d6f | 867 | __this_cpu_add(pn->lruvec_stats_percpu->state[idx], val); |
11192d9c | 868 | |
7bd5bc3c | 869 | memcg_rstat_updated(memcg, memcg_state_val_in_pages(idx, val)); |
be3e67b5 | 870 | memcg_stats_unlock(); |
db9adbcb JW |
871 | } |
872 | ||
eedc4e5a RG |
873 | /** |
874 | * __mod_lruvec_state - update lruvec memory statistics | |
875 | * @lruvec: the lruvec | |
876 | * @idx: the stat item | |
877 | * @val: delta to add to the counter, can be negative | |
878 | * | |
879 | * The lruvec is the intersection of the NUMA node and a cgroup. This | |
880 | * function updates the all three counters that are affected by a | |
881 | * change of state at this level: per-node, per-cgroup, per-lruvec. | |
882 | */ | |
883 | void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, | |
884 | int val) | |
885 | { | |
886 | /* Update node */ | |
887 | __mod_node_page_state(lruvec_pgdat(lruvec), idx, val); | |
888 | ||
889 | /* Update memcg and lruvec */ | |
890 | if (!mem_cgroup_disabled()) | |
891 | __mod_memcg_lruvec_state(lruvec, idx, val); | |
892 | } | |
893 | ||
c701123b | 894 | void __lruvec_stat_mod_folio(struct folio *folio, enum node_stat_item idx, |
c47d5032 SB |
895 | int val) |
896 | { | |
b4e0b68f | 897 | struct mem_cgroup *memcg; |
c701123b | 898 | pg_data_t *pgdat = folio_pgdat(folio); |
c47d5032 SB |
899 | struct lruvec *lruvec; |
900 | ||
b4e0b68f | 901 | rcu_read_lock(); |
c701123b | 902 | memcg = folio_memcg(folio); |
c47d5032 | 903 | /* Untracked pages have no memcg, no lruvec. Update only the node */ |
d635a69d | 904 | if (!memcg) { |
b4e0b68f | 905 | rcu_read_unlock(); |
c47d5032 SB |
906 | __mod_node_page_state(pgdat, idx, val); |
907 | return; | |
908 | } | |
909 | ||
d635a69d | 910 | lruvec = mem_cgroup_lruvec(memcg, pgdat); |
c47d5032 | 911 | __mod_lruvec_state(lruvec, idx, val); |
b4e0b68f | 912 | rcu_read_unlock(); |
c47d5032 | 913 | } |
c701123b | 914 | EXPORT_SYMBOL(__lruvec_stat_mod_folio); |
c47d5032 | 915 | |
da3ceeff | 916 | void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) |
ec9f0238 | 917 | { |
4f103c63 | 918 | pg_data_t *pgdat = page_pgdat(virt_to_page(p)); |
ec9f0238 RG |
919 | struct mem_cgroup *memcg; |
920 | struct lruvec *lruvec; | |
921 | ||
922 | rcu_read_lock(); | |
fc4db90f | 923 | memcg = mem_cgroup_from_slab_obj(p); |
ec9f0238 | 924 | |
8faeb1ff MS |
925 | /* |
926 | * Untracked pages have no memcg, no lruvec. Update only the | |
927 | * node. If we reparent the slab objects to the root memcg, | |
928 | * when we free the slab object, we need to update the per-memcg | |
929 | * vmstats to keep it correct for the root memcg. | |
930 | */ | |
931 | if (!memcg) { | |
ec9f0238 RG |
932 | __mod_node_page_state(pgdat, idx, val); |
933 | } else { | |
867e5e1d | 934 | lruvec = mem_cgroup_lruvec(memcg, pgdat); |
ec9f0238 RG |
935 | __mod_lruvec_state(lruvec, idx, val); |
936 | } | |
937 | rcu_read_unlock(); | |
938 | } | |
939 | ||
db9adbcb JW |
940 | /** |
941 | * __count_memcg_events - account VM events in a cgroup | |
942 | * @memcg: the memory cgroup | |
943 | * @idx: the event item | |
f0953a1b | 944 | * @count: the number of events that occurred |
db9adbcb JW |
945 | */ |
946 | void __count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx, | |
947 | unsigned long count) | |
948 | { | |
8278f1c7 SB |
949 | int index = memcg_events_index(idx); |
950 | ||
951 | if (mem_cgroup_disabled() || index < 0) | |
db9adbcb JW |
952 | return; |
953 | ||
be3e67b5 | 954 | memcg_stats_lock(); |
8278f1c7 | 955 | __this_cpu_add(memcg->vmstats_percpu->events[index], count); |
5b3be698 | 956 | memcg_rstat_updated(memcg, count); |
be3e67b5 | 957 | memcg_stats_unlock(); |
db9adbcb JW |
958 | } |
959 | ||
42a30035 | 960 | static unsigned long memcg_events(struct mem_cgroup *memcg, int event) |
e9f8974f | 961 | { |
8278f1c7 SB |
962 | int index = memcg_events_index(event); |
963 | ||
964 | if (index < 0) | |
965 | return 0; | |
966 | return READ_ONCE(memcg->vmstats->events[index]); | |
e9f8974f JW |
967 | } |
968 | ||
42a30035 JW |
969 | static unsigned long memcg_events_local(struct mem_cgroup *memcg, int event) |
970 | { | |
8278f1c7 SB |
971 | int index = memcg_events_index(event); |
972 | ||
973 | if (index < 0) | |
974 | return 0; | |
815744d7 | 975 | |
f82e6bf9 | 976 | return READ_ONCE(memcg->vmstats->events_local[index]); |
42a30035 JW |
977 | } |
978 | ||
c0ff4b85 | 979 | static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, |
3fba69a5 | 980 | int nr_pages) |
d52aa412 | 981 | { |
e401f176 KH |
982 | /* pagein of a big page is an event. So, ignore page size */ |
983 | if (nr_pages > 0) | |
c9019e9b | 984 | __count_memcg_events(memcg, PGPGIN, 1); |
3751d604 | 985 | else { |
c9019e9b | 986 | __count_memcg_events(memcg, PGPGOUT, 1); |
3751d604 KH |
987 | nr_pages = -nr_pages; /* for event */ |
988 | } | |
e401f176 | 989 | |
871789d4 | 990 | __this_cpu_add(memcg->vmstats_percpu->nr_page_events, nr_pages); |
6d12e2d8 KH |
991 | } |
992 | ||
f53d7ce3 JW |
993 | static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg, |
994 | enum mem_cgroup_events_target target) | |
7a159cc9 JW |
995 | { |
996 | unsigned long val, next; | |
997 | ||
871789d4 CD |
998 | val = __this_cpu_read(memcg->vmstats_percpu->nr_page_events); |
999 | next = __this_cpu_read(memcg->vmstats_percpu->targets[target]); | |
7a159cc9 | 1000 | /* from time_after() in jiffies.h */ |
6a1a8b80 | 1001 | if ((long)(next - val) < 0) { |
f53d7ce3 JW |
1002 | switch (target) { |
1003 | case MEM_CGROUP_TARGET_THRESH: | |
1004 | next = val + THRESHOLDS_EVENTS_TARGET; | |
1005 | break; | |
bb4cc1a8 AM |
1006 | case MEM_CGROUP_TARGET_SOFTLIMIT: |
1007 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
1008 | break; | |
f53d7ce3 JW |
1009 | default: |
1010 | break; | |
1011 | } | |
871789d4 | 1012 | __this_cpu_write(memcg->vmstats_percpu->targets[target], next); |
f53d7ce3 | 1013 | return true; |
7a159cc9 | 1014 | } |
f53d7ce3 | 1015 | return false; |
d2265e6f KH |
1016 | } |
1017 | ||
1018 | /* | |
1019 | * Check events in order. | |
1020 | * | |
1021 | */ | |
8e88bd2d | 1022 | static void memcg_check_events(struct mem_cgroup *memcg, int nid) |
d2265e6f | 1023 | { |
2343e88d SAS |
1024 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) |
1025 | return; | |
1026 | ||
d2265e6f | 1027 | /* threshold event is triggered in finer grain than soft limit */ |
f53d7ce3 JW |
1028 | if (unlikely(mem_cgroup_event_ratelimit(memcg, |
1029 | MEM_CGROUP_TARGET_THRESH))) { | |
bb4cc1a8 | 1030 | bool do_softlimit; |
f53d7ce3 | 1031 | |
bb4cc1a8 AM |
1032 | do_softlimit = mem_cgroup_event_ratelimit(memcg, |
1033 | MEM_CGROUP_TARGET_SOFTLIMIT); | |
c0ff4b85 | 1034 | mem_cgroup_threshold(memcg); |
bb4cc1a8 | 1035 | if (unlikely(do_softlimit)) |
8e88bd2d | 1036 | mem_cgroup_update_tree(memcg, nid); |
0a31bc97 | 1037 | } |
d2265e6f KH |
1038 | } |
1039 | ||
cf475ad2 | 1040 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 1041 | { |
31a78f23 BS |
1042 | /* |
1043 | * mm_update_next_owner() may clear mm->owner to NULL | |
1044 | * if it races with swapoff, page migration, etc. | |
1045 | * So this can be called with p == NULL. | |
1046 | */ | |
1047 | if (unlikely(!p)) | |
1048 | return NULL; | |
1049 | ||
073219e9 | 1050 | return mem_cgroup_from_css(task_css(p, memory_cgrp_id)); |
78fb7466 | 1051 | } |
33398cf2 | 1052 | EXPORT_SYMBOL(mem_cgroup_from_task); |
78fb7466 | 1053 | |
04f94e3f DS |
1054 | static __always_inline struct mem_cgroup *active_memcg(void) |
1055 | { | |
55a68c82 | 1056 | if (!in_task()) |
04f94e3f DS |
1057 | return this_cpu_read(int_active_memcg); |
1058 | else | |
1059 | return current->active_memcg; | |
1060 | } | |
1061 | ||
d46eb14b SB |
1062 | /** |
1063 | * get_mem_cgroup_from_mm: Obtain a reference on given mm_struct's memcg. | |
1064 | * @mm: mm from which memcg should be extracted. It can be NULL. | |
1065 | * | |
04f94e3f DS |
1066 | * Obtain a reference on mm->memcg and returns it if successful. If mm |
1067 | * is NULL, then the memcg is chosen as follows: | |
1068 | * 1) The active memcg, if set. | |
1069 | * 2) current->mm->memcg, if available | |
1070 | * 3) root memcg | |
1071 | * If mem_cgroup is disabled, NULL is returned. | |
d46eb14b SB |
1072 | */ |
1073 | struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm) | |
54595fe2 | 1074 | { |
d46eb14b SB |
1075 | struct mem_cgroup *memcg; |
1076 | ||
1077 | if (mem_cgroup_disabled()) | |
1078 | return NULL; | |
0b7f569e | 1079 | |
2884b6b7 MS |
1080 | /* |
1081 | * Page cache insertions can happen without an | |
1082 | * actual mm context, e.g. during disk probing | |
1083 | * on boot, loopback IO, acct() writes etc. | |
1084 | * | |
1085 | * No need to css_get on root memcg as the reference | |
1086 | * counting is disabled on the root level in the | |
1087 | * cgroup core. See CSS_NO_REF. | |
1088 | */ | |
04f94e3f DS |
1089 | if (unlikely(!mm)) { |
1090 | memcg = active_memcg(); | |
1091 | if (unlikely(memcg)) { | |
1092 | /* remote memcg must hold a ref */ | |
1093 | css_get(&memcg->css); | |
1094 | return memcg; | |
1095 | } | |
1096 | mm = current->mm; | |
1097 | if (unlikely(!mm)) | |
1098 | return root_mem_cgroup; | |
1099 | } | |
2884b6b7 | 1100 | |
54595fe2 KH |
1101 | rcu_read_lock(); |
1102 | do { | |
2884b6b7 MS |
1103 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); |
1104 | if (unlikely(!memcg)) | |
df381975 | 1105 | memcg = root_mem_cgroup; |
00d484f3 | 1106 | } while (!css_tryget(&memcg->css)); |
54595fe2 | 1107 | rcu_read_unlock(); |
c0ff4b85 | 1108 | return memcg; |
54595fe2 | 1109 | } |
d46eb14b SB |
1110 | EXPORT_SYMBOL(get_mem_cgroup_from_mm); |
1111 | ||
4b569387 NP |
1112 | /** |
1113 | * get_mem_cgroup_from_current - Obtain a reference on current task's memcg. | |
1114 | */ | |
1115 | struct mem_cgroup *get_mem_cgroup_from_current(void) | |
1116 | { | |
1117 | struct mem_cgroup *memcg; | |
1118 | ||
1119 | if (mem_cgroup_disabled()) | |
1120 | return NULL; | |
1121 | ||
1122 | again: | |
1123 | rcu_read_lock(); | |
1124 | memcg = mem_cgroup_from_task(current); | |
1125 | if (!css_tryget(&memcg->css)) { | |
1126 | rcu_read_unlock(); | |
1127 | goto again; | |
1128 | } | |
1129 | rcu_read_unlock(); | |
1130 | return memcg; | |
1131 | } | |
1132 | ||
5660048c JW |
1133 | /** |
1134 | * mem_cgroup_iter - iterate over memory cgroup hierarchy | |
1135 | * @root: hierarchy root | |
1136 | * @prev: previously returned memcg, NULL on first invocation | |
1137 | * @reclaim: cookie for shared reclaim walks, NULL for full walks | |
1138 | * | |
1139 | * Returns references to children of the hierarchy below @root, or | |
1140 | * @root itself, or %NULL after a full round-trip. | |
1141 | * | |
1142 | * Caller must pass the return value in @prev on subsequent | |
1143 | * invocations for reference counting, or use mem_cgroup_iter_break() | |
1144 | * to cancel a hierarchy walk before the round-trip is complete. | |
1145 | * | |
05bdc520 ML |
1146 | * Reclaimers can specify a node in @reclaim to divide up the memcgs |
1147 | * in the hierarchy among all concurrent reclaimers operating on the | |
1148 | * same node. | |
5660048c | 1149 | */ |
694fbc0f | 1150 | struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, |
5660048c | 1151 | struct mem_cgroup *prev, |
694fbc0f | 1152 | struct mem_cgroup_reclaim_cookie *reclaim) |
14067bb3 | 1153 | { |
3f649ab7 | 1154 | struct mem_cgroup_reclaim_iter *iter; |
5ac8fb31 | 1155 | struct cgroup_subsys_state *css = NULL; |
9f3a0d09 | 1156 | struct mem_cgroup *memcg = NULL; |
5ac8fb31 | 1157 | struct mem_cgroup *pos = NULL; |
711d3d2c | 1158 | |
694fbc0f AM |
1159 | if (mem_cgroup_disabled()) |
1160 | return NULL; | |
5660048c | 1161 | |
9f3a0d09 JW |
1162 | if (!root) |
1163 | root = root_mem_cgroup; | |
7d74b06f | 1164 | |
542f85f9 | 1165 | rcu_read_lock(); |
5f578161 | 1166 | |
5ac8fb31 | 1167 | if (reclaim) { |
ef8f2327 | 1168 | struct mem_cgroup_per_node *mz; |
5ac8fb31 | 1169 | |
a3747b53 | 1170 | mz = root->nodeinfo[reclaim->pgdat->node_id]; |
9da83f3f | 1171 | iter = &mz->iter; |
5ac8fb31 | 1172 | |
a9320aae WY |
1173 | /* |
1174 | * On start, join the current reclaim iteration cycle. | |
1175 | * Exit when a concurrent walker completes it. | |
1176 | */ | |
1177 | if (!prev) | |
1178 | reclaim->generation = iter->generation; | |
1179 | else if (reclaim->generation != iter->generation) | |
5ac8fb31 JW |
1180 | goto out_unlock; |
1181 | ||
6df38689 | 1182 | while (1) { |
4db0c3c2 | 1183 | pos = READ_ONCE(iter->position); |
6df38689 VD |
1184 | if (!pos || css_tryget(&pos->css)) |
1185 | break; | |
5ac8fb31 | 1186 | /* |
6df38689 VD |
1187 | * css reference reached zero, so iter->position will |
1188 | * be cleared by ->css_released. However, we should not | |
1189 | * rely on this happening soon, because ->css_released | |
1190 | * is called from a work queue, and by busy-waiting we | |
1191 | * might block it. So we clear iter->position right | |
1192 | * away. | |
5ac8fb31 | 1193 | */ |
6df38689 VD |
1194 | (void)cmpxchg(&iter->position, pos, NULL); |
1195 | } | |
89d8330c WY |
1196 | } else if (prev) { |
1197 | pos = prev; | |
5ac8fb31 JW |
1198 | } |
1199 | ||
1200 | if (pos) | |
1201 | css = &pos->css; | |
1202 | ||
1203 | for (;;) { | |
1204 | css = css_next_descendant_pre(css, &root->css); | |
1205 | if (!css) { | |
1206 | /* | |
1207 | * Reclaimers share the hierarchy walk, and a | |
1208 | * new one might jump in right at the end of | |
1209 | * the hierarchy - make sure they see at least | |
1210 | * one group and restart from the beginning. | |
1211 | */ | |
1212 | if (!prev) | |
1213 | continue; | |
1214 | break; | |
527a5ec9 | 1215 | } |
7d74b06f | 1216 | |
5ac8fb31 JW |
1217 | /* |
1218 | * Verify the css and acquire a reference. The root | |
1219 | * is provided by the caller, so we know it's alive | |
1220 | * and kicking, and don't take an extra reference. | |
1221 | */ | |
41555dad WY |
1222 | if (css == &root->css || css_tryget(css)) { |
1223 | memcg = mem_cgroup_from_css(css); | |
0b8f73e1 | 1224 | break; |
41555dad | 1225 | } |
9f3a0d09 | 1226 | } |
5ac8fb31 JW |
1227 | |
1228 | if (reclaim) { | |
5ac8fb31 | 1229 | /* |
6df38689 VD |
1230 | * The position could have already been updated by a competing |
1231 | * thread, so check that the value hasn't changed since we read | |
1232 | * it to avoid reclaiming from the same cgroup twice. | |
5ac8fb31 | 1233 | */ |
6df38689 VD |
1234 | (void)cmpxchg(&iter->position, pos, memcg); |
1235 | ||
5ac8fb31 JW |
1236 | if (pos) |
1237 | css_put(&pos->css); | |
1238 | ||
1239 | if (!memcg) | |
1240 | iter->generation++; | |
9f3a0d09 | 1241 | } |
5ac8fb31 | 1242 | |
542f85f9 MH |
1243 | out_unlock: |
1244 | rcu_read_unlock(); | |
c40046f3 MH |
1245 | if (prev && prev != root) |
1246 | css_put(&prev->css); | |
1247 | ||
9f3a0d09 | 1248 | return memcg; |
14067bb3 | 1249 | } |
7d74b06f | 1250 | |
5660048c JW |
1251 | /** |
1252 | * mem_cgroup_iter_break - abort a hierarchy walk prematurely | |
1253 | * @root: hierarchy root | |
1254 | * @prev: last visited hierarchy member as returned by mem_cgroup_iter() | |
1255 | */ | |
1256 | void mem_cgroup_iter_break(struct mem_cgroup *root, | |
1257 | struct mem_cgroup *prev) | |
9f3a0d09 JW |
1258 | { |
1259 | if (!root) | |
1260 | root = root_mem_cgroup; | |
1261 | if (prev && prev != root) | |
1262 | css_put(&prev->css); | |
1263 | } | |
7d74b06f | 1264 | |
54a83d6b MC |
1265 | static void __invalidate_reclaim_iterators(struct mem_cgroup *from, |
1266 | struct mem_cgroup *dead_memcg) | |
6df38689 | 1267 | { |
6df38689 | 1268 | struct mem_cgroup_reclaim_iter *iter; |
ef8f2327 MG |
1269 | struct mem_cgroup_per_node *mz; |
1270 | int nid; | |
6df38689 | 1271 | |
54a83d6b | 1272 | for_each_node(nid) { |
a3747b53 | 1273 | mz = from->nodeinfo[nid]; |
9da83f3f YS |
1274 | iter = &mz->iter; |
1275 | cmpxchg(&iter->position, dead_memcg, NULL); | |
6df38689 VD |
1276 | } |
1277 | } | |
1278 | ||
54a83d6b MC |
1279 | static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg) |
1280 | { | |
1281 | struct mem_cgroup *memcg = dead_memcg; | |
1282 | struct mem_cgroup *last; | |
1283 | ||
1284 | do { | |
1285 | __invalidate_reclaim_iterators(memcg, dead_memcg); | |
1286 | last = memcg; | |
1287 | } while ((memcg = parent_mem_cgroup(memcg))); | |
1288 | ||
1289 | /* | |
b8dd3ee9 | 1290 | * When cgroup1 non-hierarchy mode is used, |
54a83d6b MC |
1291 | * parent_mem_cgroup() does not walk all the way up to the |
1292 | * cgroup root (root_mem_cgroup). So we have to handle | |
1293 | * dead_memcg from cgroup root separately. | |
1294 | */ | |
7848ed62 | 1295 | if (!mem_cgroup_is_root(last)) |
54a83d6b MC |
1296 | __invalidate_reclaim_iterators(root_mem_cgroup, |
1297 | dead_memcg); | |
1298 | } | |
1299 | ||
7c5f64f8 VD |
1300 | /** |
1301 | * mem_cgroup_scan_tasks - iterate over tasks of a memory cgroup hierarchy | |
1302 | * @memcg: hierarchy root | |
1303 | * @fn: function to call for each task | |
1304 | * @arg: argument passed to @fn | |
1305 | * | |
1306 | * This function iterates over tasks attached to @memcg or to any of its | |
1307 | * descendants and calls @fn for each task. If @fn returns a non-zero | |
025b7799 Z |
1308 | * value, the function breaks the iteration loop. Otherwise, it will iterate |
1309 | * over all tasks and return 0. | |
7c5f64f8 VD |
1310 | * |
1311 | * This function must not be called for the root memory cgroup. | |
1312 | */ | |
025b7799 Z |
1313 | void mem_cgroup_scan_tasks(struct mem_cgroup *memcg, |
1314 | int (*fn)(struct task_struct *, void *), void *arg) | |
7c5f64f8 VD |
1315 | { |
1316 | struct mem_cgroup *iter; | |
1317 | int ret = 0; | |
1318 | ||
7848ed62 | 1319 | BUG_ON(mem_cgroup_is_root(memcg)); |
7c5f64f8 VD |
1320 | |
1321 | for_each_mem_cgroup_tree(iter, memcg) { | |
1322 | struct css_task_iter it; | |
1323 | struct task_struct *task; | |
1324 | ||
f168a9a5 | 1325 | css_task_iter_start(&iter->css, CSS_TASK_ITER_PROCS, &it); |
7c5f64f8 VD |
1326 | while (!ret && (task = css_task_iter_next(&it))) |
1327 | ret = fn(task, arg); | |
1328 | css_task_iter_end(&it); | |
1329 | if (ret) { | |
1330 | mem_cgroup_iter_break(memcg, iter); | |
1331 | break; | |
1332 | } | |
1333 | } | |
7c5f64f8 VD |
1334 | } |
1335 | ||
6168d0da | 1336 | #ifdef CONFIG_DEBUG_VM |
e809c3fe | 1337 | void lruvec_memcg_debug(struct lruvec *lruvec, struct folio *folio) |
6168d0da AS |
1338 | { |
1339 | struct mem_cgroup *memcg; | |
1340 | ||
1341 | if (mem_cgroup_disabled()) | |
1342 | return; | |
1343 | ||
e809c3fe | 1344 | memcg = folio_memcg(folio); |
6168d0da AS |
1345 | |
1346 | if (!memcg) | |
7848ed62 | 1347 | VM_BUG_ON_FOLIO(!mem_cgroup_is_root(lruvec_memcg(lruvec)), folio); |
6168d0da | 1348 | else |
e809c3fe | 1349 | VM_BUG_ON_FOLIO(lruvec_memcg(lruvec) != memcg, folio); |
6168d0da AS |
1350 | } |
1351 | #endif | |
1352 | ||
6168d0da | 1353 | /** |
e809c3fe MWO |
1354 | * folio_lruvec_lock - Lock the lruvec for a folio. |
1355 | * @folio: Pointer to the folio. | |
6168d0da | 1356 | * |
d7e3aba5 | 1357 | * These functions are safe to use under any of the following conditions: |
e809c3fe MWO |
1358 | * - folio locked |
1359 | * - folio_test_lru false | |
1360 | * - folio_memcg_lock() | |
1361 | * - folio frozen (refcount of 0) | |
1362 | * | |
1363 | * Return: The lruvec this folio is on with its lock held. | |
6168d0da | 1364 | */ |
e809c3fe | 1365 | struct lruvec *folio_lruvec_lock(struct folio *folio) |
6168d0da | 1366 | { |
e809c3fe | 1367 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1368 | |
6168d0da | 1369 | spin_lock(&lruvec->lru_lock); |
e809c3fe | 1370 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1371 | |
1372 | return lruvec; | |
1373 | } | |
1374 | ||
e809c3fe MWO |
1375 | /** |
1376 | * folio_lruvec_lock_irq - Lock the lruvec for a folio. | |
1377 | * @folio: Pointer to the folio. | |
1378 | * | |
1379 | * These functions are safe to use under any of the following conditions: | |
1380 | * - folio locked | |
1381 | * - folio_test_lru false | |
1382 | * - folio_memcg_lock() | |
1383 | * - folio frozen (refcount of 0) | |
1384 | * | |
1385 | * Return: The lruvec this folio is on with its lock held and interrupts | |
1386 | * disabled. | |
1387 | */ | |
1388 | struct lruvec *folio_lruvec_lock_irq(struct folio *folio) | |
6168d0da | 1389 | { |
e809c3fe | 1390 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1391 | |
6168d0da | 1392 | spin_lock_irq(&lruvec->lru_lock); |
e809c3fe | 1393 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1394 | |
1395 | return lruvec; | |
1396 | } | |
1397 | ||
e809c3fe MWO |
1398 | /** |
1399 | * folio_lruvec_lock_irqsave - Lock the lruvec for a folio. | |
1400 | * @folio: Pointer to the folio. | |
1401 | * @flags: Pointer to irqsave flags. | |
1402 | * | |
1403 | * These functions are safe to use under any of the following conditions: | |
1404 | * - folio locked | |
1405 | * - folio_test_lru false | |
1406 | * - folio_memcg_lock() | |
1407 | * - folio frozen (refcount of 0) | |
1408 | * | |
1409 | * Return: The lruvec this folio is on with its lock held and interrupts | |
1410 | * disabled. | |
1411 | */ | |
1412 | struct lruvec *folio_lruvec_lock_irqsave(struct folio *folio, | |
1413 | unsigned long *flags) | |
6168d0da | 1414 | { |
e809c3fe | 1415 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1416 | |
6168d0da | 1417 | spin_lock_irqsave(&lruvec->lru_lock, *flags); |
e809c3fe | 1418 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1419 | |
1420 | return lruvec; | |
1421 | } | |
1422 | ||
925b7673 | 1423 | /** |
fa9add64 HD |
1424 | * mem_cgroup_update_lru_size - account for adding or removing an lru page |
1425 | * @lruvec: mem_cgroup per zone lru vector | |
1426 | * @lru: index of lru list the page is sitting on | |
b4536f0c | 1427 | * @zid: zone id of the accounted pages |
fa9add64 | 1428 | * @nr_pages: positive when adding or negative when removing |
925b7673 | 1429 | * |
ca707239 | 1430 | * This function must be called under lru_lock, just before a page is added |
07ca7606 | 1431 | * to or just after a page is removed from an lru list. |
3f58a829 | 1432 | */ |
fa9add64 | 1433 | void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, |
b4536f0c | 1434 | int zid, int nr_pages) |
3f58a829 | 1435 | { |
ef8f2327 | 1436 | struct mem_cgroup_per_node *mz; |
fa9add64 | 1437 | unsigned long *lru_size; |
ca707239 | 1438 | long size; |
3f58a829 MK |
1439 | |
1440 | if (mem_cgroup_disabled()) | |
1441 | return; | |
1442 | ||
ef8f2327 | 1443 | mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); |
b4536f0c | 1444 | lru_size = &mz->lru_zone_size[zid][lru]; |
ca707239 HD |
1445 | |
1446 | if (nr_pages < 0) | |
1447 | *lru_size += nr_pages; | |
1448 | ||
1449 | size = *lru_size; | |
b4536f0c MH |
1450 | if (WARN_ONCE(size < 0, |
1451 | "%s(%p, %d, %d): lru_size %ld\n", | |
1452 | __func__, lruvec, lru, nr_pages, size)) { | |
ca707239 HD |
1453 | VM_BUG_ON(1); |
1454 | *lru_size = 0; | |
1455 | } | |
1456 | ||
1457 | if (nr_pages > 0) | |
1458 | *lru_size += nr_pages; | |
08e552c6 | 1459 | } |
544122e5 | 1460 | |
19942822 | 1461 | /** |
9d11ea9f | 1462 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
dad7557e | 1463 | * @memcg: the memory cgroup |
19942822 | 1464 | * |
9d11ea9f | 1465 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1466 | * pages. |
19942822 | 1467 | */ |
c0ff4b85 | 1468 | static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) |
19942822 | 1469 | { |
3e32cb2e JW |
1470 | unsigned long margin = 0; |
1471 | unsigned long count; | |
1472 | unsigned long limit; | |
9d11ea9f | 1473 | |
3e32cb2e | 1474 | count = page_counter_read(&memcg->memory); |
bbec2e15 | 1475 | limit = READ_ONCE(memcg->memory.max); |
3e32cb2e JW |
1476 | if (count < limit) |
1477 | margin = limit - count; | |
1478 | ||
7941d214 | 1479 | if (do_memsw_account()) { |
3e32cb2e | 1480 | count = page_counter_read(&memcg->memsw); |
bbec2e15 | 1481 | limit = READ_ONCE(memcg->memsw.max); |
1c4448ed | 1482 | if (count < limit) |
3e32cb2e | 1483 | margin = min(margin, limit - count); |
cbedbac3 LR |
1484 | else |
1485 | margin = 0; | |
3e32cb2e JW |
1486 | } |
1487 | ||
1488 | return margin; | |
19942822 JW |
1489 | } |
1490 | ||
32047e2a | 1491 | /* |
bdcbb659 | 1492 | * A routine for checking "mem" is under move_account() or not. |
32047e2a | 1493 | * |
bdcbb659 QH |
1494 | * Checking a cgroup is mc.from or mc.to or under hierarchy of |
1495 | * moving cgroups. This is for waiting at high-memory pressure | |
1496 | * caused by "move". | |
32047e2a | 1497 | */ |
c0ff4b85 | 1498 | static bool mem_cgroup_under_move(struct mem_cgroup *memcg) |
4b534334 | 1499 | { |
2bd9bb20 KH |
1500 | struct mem_cgroup *from; |
1501 | struct mem_cgroup *to; | |
4b534334 | 1502 | bool ret = false; |
2bd9bb20 KH |
1503 | /* |
1504 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1505 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1506 | */ | |
1507 | spin_lock(&mc.lock); | |
1508 | from = mc.from; | |
1509 | to = mc.to; | |
1510 | if (!from) | |
1511 | goto unlock; | |
3e92041d | 1512 | |
2314b42d JW |
1513 | ret = mem_cgroup_is_descendant(from, memcg) || |
1514 | mem_cgroup_is_descendant(to, memcg); | |
2bd9bb20 KH |
1515 | unlock: |
1516 | spin_unlock(&mc.lock); | |
4b534334 KH |
1517 | return ret; |
1518 | } | |
1519 | ||
c0ff4b85 | 1520 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) |
4b534334 KH |
1521 | { |
1522 | if (mc.moving_task && current != mc.moving_task) { | |
c0ff4b85 | 1523 | if (mem_cgroup_under_move(memcg)) { |
4b534334 KH |
1524 | DEFINE_WAIT(wait); |
1525 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1526 | /* moving charge context might have finished. */ | |
1527 | if (mc.moving_task) | |
1528 | schedule(); | |
1529 | finish_wait(&mc.waitq, &wait); | |
1530 | return true; | |
1531 | } | |
1532 | } | |
1533 | return false; | |
1534 | } | |
1535 | ||
5f9a4f4a MS |
1536 | struct memory_stat { |
1537 | const char *name; | |
5f9a4f4a MS |
1538 | unsigned int idx; |
1539 | }; | |
1540 | ||
57b2847d | 1541 | static const struct memory_stat memory_stats[] = { |
fff66b79 MS |
1542 | { "anon", NR_ANON_MAPPED }, |
1543 | { "file", NR_FILE_PAGES }, | |
a8c49af3 | 1544 | { "kernel", MEMCG_KMEM }, |
fff66b79 MS |
1545 | { "kernel_stack", NR_KERNEL_STACK_KB }, |
1546 | { "pagetables", NR_PAGETABLE }, | |
ebc97a52 | 1547 | { "sec_pagetables", NR_SECONDARY_PAGETABLE }, |
fff66b79 MS |
1548 | { "percpu", MEMCG_PERCPU_B }, |
1549 | { "sock", MEMCG_SOCK }, | |
4e5aa1f4 | 1550 | { "vmalloc", MEMCG_VMALLOC }, |
fff66b79 | 1551 | { "shmem", NR_SHMEM }, |
f4840ccf JW |
1552 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
1553 | { "zswap", MEMCG_ZSWAP_B }, | |
1554 | { "zswapped", MEMCG_ZSWAPPED }, | |
1555 | #endif | |
fff66b79 MS |
1556 | { "file_mapped", NR_FILE_MAPPED }, |
1557 | { "file_dirty", NR_FILE_DIRTY }, | |
1558 | { "file_writeback", NR_WRITEBACK }, | |
b6038942 SB |
1559 | #ifdef CONFIG_SWAP |
1560 | { "swapcached", NR_SWAPCACHE }, | |
1561 | #endif | |
5f9a4f4a | 1562 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
fff66b79 MS |
1563 | { "anon_thp", NR_ANON_THPS }, |
1564 | { "file_thp", NR_FILE_THPS }, | |
1565 | { "shmem_thp", NR_SHMEM_THPS }, | |
5f9a4f4a | 1566 | #endif |
fff66b79 MS |
1567 | { "inactive_anon", NR_INACTIVE_ANON }, |
1568 | { "active_anon", NR_ACTIVE_ANON }, | |
1569 | { "inactive_file", NR_INACTIVE_FILE }, | |
1570 | { "active_file", NR_ACTIVE_FILE }, | |
1571 | { "unevictable", NR_UNEVICTABLE }, | |
1572 | { "slab_reclaimable", NR_SLAB_RECLAIMABLE_B }, | |
1573 | { "slab_unreclaimable", NR_SLAB_UNRECLAIMABLE_B }, | |
5f9a4f4a MS |
1574 | |
1575 | /* The memory events */ | |
fff66b79 MS |
1576 | { "workingset_refault_anon", WORKINGSET_REFAULT_ANON }, |
1577 | { "workingset_refault_file", WORKINGSET_REFAULT_FILE }, | |
1578 | { "workingset_activate_anon", WORKINGSET_ACTIVATE_ANON }, | |
1579 | { "workingset_activate_file", WORKINGSET_ACTIVATE_FILE }, | |
1580 | { "workingset_restore_anon", WORKINGSET_RESTORE_ANON }, | |
1581 | { "workingset_restore_file", WORKINGSET_RESTORE_FILE }, | |
1582 | { "workingset_nodereclaim", WORKINGSET_NODERECLAIM }, | |
5f9a4f4a MS |
1583 | }; |
1584 | ||
ff841a06 | 1585 | /* The actual unit of the state item, not the same as the output unit */ |
fff66b79 MS |
1586 | static int memcg_page_state_unit(int item) |
1587 | { | |
1588 | switch (item) { | |
1589 | case MEMCG_PERCPU_B: | |
f4840ccf | 1590 | case MEMCG_ZSWAP_B: |
fff66b79 MS |
1591 | case NR_SLAB_RECLAIMABLE_B: |
1592 | case NR_SLAB_UNRECLAIMABLE_B: | |
ff841a06 YA |
1593 | return 1; |
1594 | case NR_KERNEL_STACK_KB: | |
1595 | return SZ_1K; | |
1596 | default: | |
1597 | return PAGE_SIZE; | |
1598 | } | |
1599 | } | |
1600 | ||
1601 | /* Translate stat items to the correct unit for memory.stat output */ | |
1602 | static int memcg_page_state_output_unit(int item) | |
1603 | { | |
1604 | /* | |
1605 | * Workingset state is actually in pages, but we export it to userspace | |
1606 | * as a scalar count of events, so special case it here. | |
1607 | */ | |
1608 | switch (item) { | |
fff66b79 MS |
1609 | case WORKINGSET_REFAULT_ANON: |
1610 | case WORKINGSET_REFAULT_FILE: | |
1611 | case WORKINGSET_ACTIVATE_ANON: | |
1612 | case WORKINGSET_ACTIVATE_FILE: | |
1613 | case WORKINGSET_RESTORE_ANON: | |
1614 | case WORKINGSET_RESTORE_FILE: | |
1615 | case WORKINGSET_NODERECLAIM: | |
1616 | return 1; | |
fff66b79 | 1617 | default: |
ff841a06 | 1618 | return memcg_page_state_unit(item); |
fff66b79 MS |
1619 | } |
1620 | } | |
1621 | ||
1622 | static inline unsigned long memcg_page_state_output(struct mem_cgroup *memcg, | |
1623 | int item) | |
1624 | { | |
ff841a06 YA |
1625 | return memcg_page_state(memcg, item) * |
1626 | memcg_page_state_output_unit(item); | |
1627 | } | |
1628 | ||
1629 | static inline unsigned long memcg_page_state_local_output( | |
1630 | struct mem_cgroup *memcg, int item) | |
1631 | { | |
1632 | return memcg_page_state_local(memcg, item) * | |
1633 | memcg_page_state_output_unit(item); | |
fff66b79 MS |
1634 | } |
1635 | ||
dddb44ff | 1636 | static void memcg_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) |
c8713d0b | 1637 | { |
c8713d0b | 1638 | int i; |
71cd3113 | 1639 | |
c8713d0b JW |
1640 | /* |
1641 | * Provide statistics on the state of the memory subsystem as | |
1642 | * well as cumulative event counters that show past behavior. | |
1643 | * | |
1644 | * This list is ordered following a combination of these gradients: | |
1645 | * 1) generic big picture -> specifics and details | |
1646 | * 2) reflecting userspace activity -> reflecting kernel heuristics | |
1647 | * | |
1648 | * Current memory state: | |
1649 | */ | |
7d7ef0a4 | 1650 | mem_cgroup_flush_stats(memcg); |
c8713d0b | 1651 | |
5f9a4f4a MS |
1652 | for (i = 0; i < ARRAY_SIZE(memory_stats); i++) { |
1653 | u64 size; | |
c8713d0b | 1654 | |
fff66b79 | 1655 | size = memcg_page_state_output(memcg, memory_stats[i].idx); |
5b42360c | 1656 | seq_buf_printf(s, "%s %llu\n", memory_stats[i].name, size); |
c8713d0b | 1657 | |
5f9a4f4a | 1658 | if (unlikely(memory_stats[i].idx == NR_SLAB_UNRECLAIMABLE_B)) { |
fff66b79 MS |
1659 | size += memcg_page_state_output(memcg, |
1660 | NR_SLAB_RECLAIMABLE_B); | |
5b42360c | 1661 | seq_buf_printf(s, "slab %llu\n", size); |
5f9a4f4a MS |
1662 | } |
1663 | } | |
c8713d0b JW |
1664 | |
1665 | /* Accumulated memory events */ | |
5b42360c | 1666 | seq_buf_printf(s, "pgscan %lu\n", |
c8713d0b | 1667 | memcg_events(memcg, PGSCAN_KSWAPD) + |
57e9cc50 JW |
1668 | memcg_events(memcg, PGSCAN_DIRECT) + |
1669 | memcg_events(memcg, PGSCAN_KHUGEPAGED)); | |
5b42360c | 1670 | seq_buf_printf(s, "pgsteal %lu\n", |
c8713d0b | 1671 | memcg_events(memcg, PGSTEAL_KSWAPD) + |
57e9cc50 JW |
1672 | memcg_events(memcg, PGSTEAL_DIRECT) + |
1673 | memcg_events(memcg, PGSTEAL_KHUGEPAGED)); | |
c8713d0b | 1674 | |
8278f1c7 SB |
1675 | for (i = 0; i < ARRAY_SIZE(memcg_vm_event_stat); i++) { |
1676 | if (memcg_vm_event_stat[i] == PGPGIN || | |
1677 | memcg_vm_event_stat[i] == PGPGOUT) | |
1678 | continue; | |
1679 | ||
5b42360c | 1680 | seq_buf_printf(s, "%s %lu\n", |
673520f8 QZ |
1681 | vm_event_name(memcg_vm_event_stat[i]), |
1682 | memcg_events(memcg, memcg_vm_event_stat[i])); | |
8278f1c7 | 1683 | } |
c8713d0b JW |
1684 | |
1685 | /* The above should easily fit into one page */ | |
5b42360c | 1686 | WARN_ON_ONCE(seq_buf_has_overflowed(s)); |
c8713d0b | 1687 | } |
71cd3113 | 1688 | |
dddb44ff YA |
1689 | static void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s); |
1690 | ||
1691 | static void memory_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) | |
1692 | { | |
1693 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
1694 | memcg_stat_format(memcg, s); | |
1695 | else | |
1696 | memcg1_stat_format(memcg, s); | |
1697 | WARN_ON_ONCE(seq_buf_has_overflowed(s)); | |
1698 | } | |
1699 | ||
e222432b | 1700 | /** |
f0c867d9 | 1701 | * mem_cgroup_print_oom_context: Print OOM information relevant to |
1702 | * memory controller. | |
e222432b BS |
1703 | * @memcg: The memory cgroup that went over limit |
1704 | * @p: Task that is going to be killed | |
1705 | * | |
1706 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1707 | * enabled | |
1708 | */ | |
f0c867d9 | 1709 | void mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p) |
e222432b | 1710 | { |
e222432b BS |
1711 | rcu_read_lock(); |
1712 | ||
f0c867d9 | 1713 | if (memcg) { |
1714 | pr_cont(",oom_memcg="); | |
1715 | pr_cont_cgroup_path(memcg->css.cgroup); | |
1716 | } else | |
1717 | pr_cont(",global_oom"); | |
2415b9f5 | 1718 | if (p) { |
f0c867d9 | 1719 | pr_cont(",task_memcg="); |
2415b9f5 | 1720 | pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id)); |
2415b9f5 | 1721 | } |
e222432b | 1722 | rcu_read_unlock(); |
f0c867d9 | 1723 | } |
1724 | ||
1725 | /** | |
1726 | * mem_cgroup_print_oom_meminfo: Print OOM memory information relevant to | |
1727 | * memory controller. | |
1728 | * @memcg: The memory cgroup that went over limit | |
1729 | */ | |
1730 | void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg) | |
1731 | { | |
68aaee14 TH |
1732 | /* Use static buffer, for the caller is holding oom_lock. */ |
1733 | static char buf[PAGE_SIZE]; | |
5b42360c | 1734 | struct seq_buf s; |
68aaee14 TH |
1735 | |
1736 | lockdep_assert_held(&oom_lock); | |
e222432b | 1737 | |
3e32cb2e JW |
1738 | pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n", |
1739 | K((u64)page_counter_read(&memcg->memory)), | |
15b42562 | 1740 | K((u64)READ_ONCE(memcg->memory.max)), memcg->memory.failcnt); |
c8713d0b JW |
1741 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
1742 | pr_info("swap: usage %llukB, limit %llukB, failcnt %lu\n", | |
1743 | K((u64)page_counter_read(&memcg->swap)), | |
32d087cd | 1744 | K((u64)READ_ONCE(memcg->swap.max)), memcg->swap.failcnt); |
c8713d0b JW |
1745 | else { |
1746 | pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n", | |
1747 | K((u64)page_counter_read(&memcg->memsw)), | |
1748 | K((u64)memcg->memsw.max), memcg->memsw.failcnt); | |
1749 | pr_info("kmem: usage %llukB, limit %llukB, failcnt %lu\n", | |
1750 | K((u64)page_counter_read(&memcg->kmem)), | |
1751 | K((u64)memcg->kmem.max), memcg->kmem.failcnt); | |
58cf188e | 1752 | } |
c8713d0b JW |
1753 | |
1754 | pr_info("Memory cgroup stats for "); | |
1755 | pr_cont_cgroup_path(memcg->css.cgroup); | |
1756 | pr_cont(":"); | |
5b42360c YA |
1757 | seq_buf_init(&s, buf, sizeof(buf)); |
1758 | memory_stat_format(memcg, &s); | |
1759 | seq_buf_do_printk(&s, KERN_INFO); | |
e222432b BS |
1760 | } |
1761 | ||
a63d83f4 DR |
1762 | /* |
1763 | * Return the memory (and swap, if configured) limit for a memcg. | |
1764 | */ | |
bbec2e15 | 1765 | unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg) |
a63d83f4 | 1766 | { |
8d387a5f WL |
1767 | unsigned long max = READ_ONCE(memcg->memory.max); |
1768 | ||
b94c4e94 | 1769 | if (do_memsw_account()) { |
8d387a5f WL |
1770 | if (mem_cgroup_swappiness(memcg)) { |
1771 | /* Calculate swap excess capacity from memsw limit */ | |
1772 | unsigned long swap = READ_ONCE(memcg->memsw.max) - max; | |
1773 | ||
1774 | max += min(swap, (unsigned long)total_swap_pages); | |
1775 | } | |
b94c4e94 JW |
1776 | } else { |
1777 | if (mem_cgroup_swappiness(memcg)) | |
1778 | max += min(READ_ONCE(memcg->swap.max), | |
1779 | (unsigned long)total_swap_pages); | |
9a5a8f19 | 1780 | } |
bbec2e15 | 1781 | return max; |
a63d83f4 DR |
1782 | } |
1783 | ||
9783aa99 CD |
1784 | unsigned long mem_cgroup_size(struct mem_cgroup *memcg) |
1785 | { | |
1786 | return page_counter_read(&memcg->memory); | |
1787 | } | |
1788 | ||
b6e6edcf | 1789 | static bool mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, |
19965460 | 1790 | int order) |
9cbb78bb | 1791 | { |
6e0fc46d DR |
1792 | struct oom_control oc = { |
1793 | .zonelist = NULL, | |
1794 | .nodemask = NULL, | |
2a966b77 | 1795 | .memcg = memcg, |
6e0fc46d DR |
1796 | .gfp_mask = gfp_mask, |
1797 | .order = order, | |
6e0fc46d | 1798 | }; |
1378b37d | 1799 | bool ret = true; |
9cbb78bb | 1800 | |
7775face TH |
1801 | if (mutex_lock_killable(&oom_lock)) |
1802 | return true; | |
1378b37d YS |
1803 | |
1804 | if (mem_cgroup_margin(memcg) >= (1 << order)) | |
1805 | goto unlock; | |
1806 | ||
7775face TH |
1807 | /* |
1808 | * A few threads which were not waiting at mutex_lock_killable() can | |
1809 | * fail to bail out. Therefore, check again after holding oom_lock. | |
1810 | */ | |
a4ebf1b6 | 1811 | ret = task_is_dying() || out_of_memory(&oc); |
1378b37d YS |
1812 | |
1813 | unlock: | |
dc56401f | 1814 | mutex_unlock(&oom_lock); |
7c5f64f8 | 1815 | return ret; |
9cbb78bb DR |
1816 | } |
1817 | ||
0608f43d | 1818 | static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, |
ef8f2327 | 1819 | pg_data_t *pgdat, |
0608f43d AM |
1820 | gfp_t gfp_mask, |
1821 | unsigned long *total_scanned) | |
1822 | { | |
1823 | struct mem_cgroup *victim = NULL; | |
1824 | int total = 0; | |
1825 | int loop = 0; | |
1826 | unsigned long excess; | |
1827 | unsigned long nr_scanned; | |
1828 | struct mem_cgroup_reclaim_cookie reclaim = { | |
ef8f2327 | 1829 | .pgdat = pgdat, |
0608f43d AM |
1830 | }; |
1831 | ||
3e32cb2e | 1832 | excess = soft_limit_excess(root_memcg); |
0608f43d AM |
1833 | |
1834 | while (1) { | |
1835 | victim = mem_cgroup_iter(root_memcg, victim, &reclaim); | |
1836 | if (!victim) { | |
1837 | loop++; | |
1838 | if (loop >= 2) { | |
1839 | /* | |
1840 | * If we have not been able to reclaim | |
1841 | * anything, it might because there are | |
1842 | * no reclaimable pages under this hierarchy | |
1843 | */ | |
1844 | if (!total) | |
1845 | break; | |
1846 | /* | |
1847 | * We want to do more targeted reclaim. | |
1848 | * excess >> 2 is not to excessive so as to | |
1849 | * reclaim too much, nor too less that we keep | |
1850 | * coming back to reclaim from this cgroup | |
1851 | */ | |
1852 | if (total >= (excess >> 2) || | |
1853 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) | |
1854 | break; | |
1855 | } | |
1856 | continue; | |
1857 | } | |
a9dd0a83 | 1858 | total += mem_cgroup_shrink_node(victim, gfp_mask, false, |
ef8f2327 | 1859 | pgdat, &nr_scanned); |
0608f43d | 1860 | *total_scanned += nr_scanned; |
3e32cb2e | 1861 | if (!soft_limit_excess(root_memcg)) |
0608f43d | 1862 | break; |
6d61ef40 | 1863 | } |
0608f43d AM |
1864 | mem_cgroup_iter_break(root_memcg, victim); |
1865 | return total; | |
6d61ef40 BS |
1866 | } |
1867 | ||
0056f4e6 JW |
1868 | #ifdef CONFIG_LOCKDEP |
1869 | static struct lockdep_map memcg_oom_lock_dep_map = { | |
1870 | .name = "memcg_oom_lock", | |
1871 | }; | |
1872 | #endif | |
1873 | ||
fb2a6fc5 JW |
1874 | static DEFINE_SPINLOCK(memcg_oom_lock); |
1875 | ||
867578cb KH |
1876 | /* |
1877 | * Check OOM-Killer is already running under our hierarchy. | |
1878 | * If someone is running, return false. | |
1879 | */ | |
fb2a6fc5 | 1880 | static bool mem_cgroup_oom_trylock(struct mem_cgroup *memcg) |
867578cb | 1881 | { |
79dfdacc | 1882 | struct mem_cgroup *iter, *failed = NULL; |
a636b327 | 1883 | |
fb2a6fc5 JW |
1884 | spin_lock(&memcg_oom_lock); |
1885 | ||
9f3a0d09 | 1886 | for_each_mem_cgroup_tree(iter, memcg) { |
23751be0 | 1887 | if (iter->oom_lock) { |
79dfdacc MH |
1888 | /* |
1889 | * this subtree of our hierarchy is already locked | |
1890 | * so we cannot give a lock. | |
1891 | */ | |
79dfdacc | 1892 | failed = iter; |
9f3a0d09 JW |
1893 | mem_cgroup_iter_break(memcg, iter); |
1894 | break; | |
23751be0 JW |
1895 | } else |
1896 | iter->oom_lock = true; | |
7d74b06f | 1897 | } |
867578cb | 1898 | |
fb2a6fc5 JW |
1899 | if (failed) { |
1900 | /* | |
1901 | * OK, we failed to lock the whole subtree so we have | |
1902 | * to clean up what we set up to the failing subtree | |
1903 | */ | |
1904 | for_each_mem_cgroup_tree(iter, memcg) { | |
1905 | if (iter == failed) { | |
1906 | mem_cgroup_iter_break(memcg, iter); | |
1907 | break; | |
1908 | } | |
1909 | iter->oom_lock = false; | |
79dfdacc | 1910 | } |
0056f4e6 JW |
1911 | } else |
1912 | mutex_acquire(&memcg_oom_lock_dep_map, 0, 1, _RET_IP_); | |
fb2a6fc5 JW |
1913 | |
1914 | spin_unlock(&memcg_oom_lock); | |
1915 | ||
1916 | return !failed; | |
a636b327 | 1917 | } |
0b7f569e | 1918 | |
fb2a6fc5 | 1919 | static void mem_cgroup_oom_unlock(struct mem_cgroup *memcg) |
0b7f569e | 1920 | { |
7d74b06f KH |
1921 | struct mem_cgroup *iter; |
1922 | ||
fb2a6fc5 | 1923 | spin_lock(&memcg_oom_lock); |
5facae4f | 1924 | mutex_release(&memcg_oom_lock_dep_map, _RET_IP_); |
c0ff4b85 | 1925 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc | 1926 | iter->oom_lock = false; |
fb2a6fc5 | 1927 | spin_unlock(&memcg_oom_lock); |
79dfdacc MH |
1928 | } |
1929 | ||
c0ff4b85 | 1930 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1931 | { |
1932 | struct mem_cgroup *iter; | |
1933 | ||
c2b42d3c | 1934 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1935 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1936 | iter->under_oom++; |
1937 | spin_unlock(&memcg_oom_lock); | |
79dfdacc MH |
1938 | } |
1939 | ||
c0ff4b85 | 1940 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1941 | { |
1942 | struct mem_cgroup *iter; | |
1943 | ||
867578cb | 1944 | /* |
f0953a1b | 1945 | * Be careful about under_oom underflows because a child memcg |
7a52d4d8 | 1946 | * could have been added after mem_cgroup_mark_under_oom. |
867578cb | 1947 | */ |
c2b42d3c | 1948 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1949 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1950 | if (iter->under_oom > 0) |
1951 | iter->under_oom--; | |
1952 | spin_unlock(&memcg_oom_lock); | |
0b7f569e KH |
1953 | } |
1954 | ||
867578cb KH |
1955 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1956 | ||
dc98df5a | 1957 | struct oom_wait_info { |
d79154bb | 1958 | struct mem_cgroup *memcg; |
ac6424b9 | 1959 | wait_queue_entry_t wait; |
dc98df5a KH |
1960 | }; |
1961 | ||
ac6424b9 | 1962 | static int memcg_oom_wake_function(wait_queue_entry_t *wait, |
dc98df5a KH |
1963 | unsigned mode, int sync, void *arg) |
1964 | { | |
d79154bb HD |
1965 | struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg; |
1966 | struct mem_cgroup *oom_wait_memcg; | |
dc98df5a KH |
1967 | struct oom_wait_info *oom_wait_info; |
1968 | ||
1969 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
d79154bb | 1970 | oom_wait_memcg = oom_wait_info->memcg; |
dc98df5a | 1971 | |
2314b42d JW |
1972 | if (!mem_cgroup_is_descendant(wake_memcg, oom_wait_memcg) && |
1973 | !mem_cgroup_is_descendant(oom_wait_memcg, wake_memcg)) | |
dc98df5a | 1974 | return 0; |
dc98df5a KH |
1975 | return autoremove_wake_function(wait, mode, sync, arg); |
1976 | } | |
1977 | ||
c0ff4b85 | 1978 | static void memcg_oom_recover(struct mem_cgroup *memcg) |
3c11ecf4 | 1979 | { |
c2b42d3c TH |
1980 | /* |
1981 | * For the following lockless ->under_oom test, the only required | |
1982 | * guarantee is that it must see the state asserted by an OOM when | |
1983 | * this function is called as a result of userland actions | |
1984 | * triggered by the notification of the OOM. This is trivially | |
1985 | * achieved by invoking mem_cgroup_mark_under_oom() before | |
1986 | * triggering notification. | |
1987 | */ | |
1988 | if (memcg && memcg->under_oom) | |
f4b90b70 | 1989 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg); |
3c11ecf4 KH |
1990 | } |
1991 | ||
becdf89d SB |
1992 | /* |
1993 | * Returns true if successfully killed one or more processes. Though in some | |
1994 | * corner cases it can return true even without killing any process. | |
1995 | */ | |
1996 | static bool mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order) | |
0b7f569e | 1997 | { |
becdf89d | 1998 | bool locked, ret; |
7056d3a3 | 1999 | |
29ef680a | 2000 | if (order > PAGE_ALLOC_COSTLY_ORDER) |
becdf89d | 2001 | return false; |
29ef680a | 2002 | |
7a1adfdd RG |
2003 | memcg_memory_event(memcg, MEMCG_OOM); |
2004 | ||
867578cb | 2005 | /* |
49426420 JW |
2006 | * We are in the middle of the charge context here, so we |
2007 | * don't want to block when potentially sitting on a callstack | |
2008 | * that holds all kinds of filesystem and mm locks. | |
2009 | * | |
29ef680a MH |
2010 | * cgroup1 allows disabling the OOM killer and waiting for outside |
2011 | * handling until the charge can succeed; remember the context and put | |
2012 | * the task to sleep at the end of the page fault when all locks are | |
2013 | * released. | |
49426420 | 2014 | * |
29ef680a MH |
2015 | * On the other hand, in-kernel OOM killer allows for an async victim |
2016 | * memory reclaim (oom_reaper) and that means that we are not solely | |
2017 | * relying on the oom victim to make a forward progress and we can | |
2018 | * invoke the oom killer here. | |
2019 | * | |
2020 | * Please note that mem_cgroup_out_of_memory might fail to find a | |
2021 | * victim and then we have to bail out from the charge path. | |
867578cb | 2022 | */ |
17c56de6 | 2023 | if (READ_ONCE(memcg->oom_kill_disable)) { |
becdf89d SB |
2024 | if (current->in_user_fault) { |
2025 | css_get(&memcg->css); | |
2026 | current->memcg_in_oom = memcg; | |
2027 | current->memcg_oom_gfp_mask = mask; | |
2028 | current->memcg_oom_order = order; | |
2029 | } | |
2030 | return false; | |
29ef680a MH |
2031 | } |
2032 | ||
7056d3a3 MH |
2033 | mem_cgroup_mark_under_oom(memcg); |
2034 | ||
2035 | locked = mem_cgroup_oom_trylock(memcg); | |
2036 | ||
2037 | if (locked) | |
2038 | mem_cgroup_oom_notify(memcg); | |
2039 | ||
2040 | mem_cgroup_unmark_under_oom(memcg); | |
becdf89d | 2041 | ret = mem_cgroup_out_of_memory(memcg, mask, order); |
7056d3a3 MH |
2042 | |
2043 | if (locked) | |
2044 | mem_cgroup_oom_unlock(memcg); | |
29ef680a | 2045 | |
7056d3a3 | 2046 | return ret; |
3812c8c8 JW |
2047 | } |
2048 | ||
2049 | /** | |
2050 | * mem_cgroup_oom_synchronize - complete memcg OOM handling | |
49426420 | 2051 | * @handle: actually kill/wait or just clean up the OOM state |
3812c8c8 | 2052 | * |
49426420 JW |
2053 | * This has to be called at the end of a page fault if the memcg OOM |
2054 | * handler was enabled. | |
3812c8c8 | 2055 | * |
49426420 | 2056 | * Memcg supports userspace OOM handling where failed allocations must |
3812c8c8 JW |
2057 | * sleep on a waitqueue until the userspace task resolves the |
2058 | * situation. Sleeping directly in the charge context with all kinds | |
2059 | * of locks held is not a good idea, instead we remember an OOM state | |
2060 | * in the task and mem_cgroup_oom_synchronize() has to be called at | |
49426420 | 2061 | * the end of the page fault to complete the OOM handling. |
3812c8c8 JW |
2062 | * |
2063 | * Returns %true if an ongoing memcg OOM situation was detected and | |
49426420 | 2064 | * completed, %false otherwise. |
3812c8c8 | 2065 | */ |
49426420 | 2066 | bool mem_cgroup_oom_synchronize(bool handle) |
3812c8c8 | 2067 | { |
626ebc41 | 2068 | struct mem_cgroup *memcg = current->memcg_in_oom; |
3812c8c8 | 2069 | struct oom_wait_info owait; |
49426420 | 2070 | bool locked; |
3812c8c8 JW |
2071 | |
2072 | /* OOM is global, do not handle */ | |
3812c8c8 | 2073 | if (!memcg) |
49426420 | 2074 | return false; |
3812c8c8 | 2075 | |
7c5f64f8 | 2076 | if (!handle) |
49426420 | 2077 | goto cleanup; |
3812c8c8 JW |
2078 | |
2079 | owait.memcg = memcg; | |
2080 | owait.wait.flags = 0; | |
2081 | owait.wait.func = memcg_oom_wake_function; | |
2082 | owait.wait.private = current; | |
2055da97 | 2083 | INIT_LIST_HEAD(&owait.wait.entry); |
867578cb | 2084 | |
3812c8c8 | 2085 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
49426420 JW |
2086 | mem_cgroup_mark_under_oom(memcg); |
2087 | ||
2088 | locked = mem_cgroup_oom_trylock(memcg); | |
2089 | ||
2090 | if (locked) | |
2091 | mem_cgroup_oom_notify(memcg); | |
2092 | ||
857f2139 HX |
2093 | schedule(); |
2094 | mem_cgroup_unmark_under_oom(memcg); | |
2095 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
49426420 | 2096 | |
18b1d18b | 2097 | if (locked) |
fb2a6fc5 | 2098 | mem_cgroup_oom_unlock(memcg); |
49426420 | 2099 | cleanup: |
626ebc41 | 2100 | current->memcg_in_oom = NULL; |
3812c8c8 | 2101 | css_put(&memcg->css); |
867578cb | 2102 | return true; |
0b7f569e KH |
2103 | } |
2104 | ||
3d8b38eb RG |
2105 | /** |
2106 | * mem_cgroup_get_oom_group - get a memory cgroup to clean up after OOM | |
2107 | * @victim: task to be killed by the OOM killer | |
2108 | * @oom_domain: memcg in case of memcg OOM, NULL in case of system-wide OOM | |
2109 | * | |
2110 | * Returns a pointer to a memory cgroup, which has to be cleaned up | |
2111 | * by killing all belonging OOM-killable tasks. | |
2112 | * | |
2113 | * Caller has to call mem_cgroup_put() on the returned non-NULL memcg. | |
2114 | */ | |
2115 | struct mem_cgroup *mem_cgroup_get_oom_group(struct task_struct *victim, | |
2116 | struct mem_cgroup *oom_domain) | |
2117 | { | |
2118 | struct mem_cgroup *oom_group = NULL; | |
2119 | struct mem_cgroup *memcg; | |
2120 | ||
2121 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
2122 | return NULL; | |
2123 | ||
2124 | if (!oom_domain) | |
2125 | oom_domain = root_mem_cgroup; | |
2126 | ||
2127 | rcu_read_lock(); | |
2128 | ||
2129 | memcg = mem_cgroup_from_task(victim); | |
7848ed62 | 2130 | if (mem_cgroup_is_root(memcg)) |
3d8b38eb RG |
2131 | goto out; |
2132 | ||
48fe267c RG |
2133 | /* |
2134 | * If the victim task has been asynchronously moved to a different | |
2135 | * memory cgroup, we might end up killing tasks outside oom_domain. | |
2136 | * In this case it's better to ignore memory.group.oom. | |
2137 | */ | |
2138 | if (unlikely(!mem_cgroup_is_descendant(memcg, oom_domain))) | |
2139 | goto out; | |
2140 | ||
3d8b38eb RG |
2141 | /* |
2142 | * Traverse the memory cgroup hierarchy from the victim task's | |
2143 | * cgroup up to the OOMing cgroup (or root) to find the | |
2144 | * highest-level memory cgroup with oom.group set. | |
2145 | */ | |
2146 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
eaf7b66b | 2147 | if (READ_ONCE(memcg->oom_group)) |
3d8b38eb RG |
2148 | oom_group = memcg; |
2149 | ||
2150 | if (memcg == oom_domain) | |
2151 | break; | |
2152 | } | |
2153 | ||
2154 | if (oom_group) | |
2155 | css_get(&oom_group->css); | |
2156 | out: | |
2157 | rcu_read_unlock(); | |
2158 | ||
2159 | return oom_group; | |
2160 | } | |
2161 | ||
2162 | void mem_cgroup_print_oom_group(struct mem_cgroup *memcg) | |
2163 | { | |
2164 | pr_info("Tasks in "); | |
2165 | pr_cont_cgroup_path(memcg->css.cgroup); | |
2166 | pr_cont(" are going to be killed due to memory.oom.group set\n"); | |
2167 | } | |
2168 | ||
d7365e78 | 2169 | /** |
f70ad448 MWO |
2170 | * folio_memcg_lock - Bind a folio to its memcg. |
2171 | * @folio: The folio. | |
32047e2a | 2172 | * |
f70ad448 | 2173 | * This function prevents unlocked LRU folios from being moved to |
739f79fc JW |
2174 | * another cgroup. |
2175 | * | |
f70ad448 MWO |
2176 | * It ensures lifetime of the bound memcg. The caller is responsible |
2177 | * for the lifetime of the folio. | |
d69b042f | 2178 | */ |
f70ad448 | 2179 | void folio_memcg_lock(struct folio *folio) |
89c06bd5 KH |
2180 | { |
2181 | struct mem_cgroup *memcg; | |
6de22619 | 2182 | unsigned long flags; |
89c06bd5 | 2183 | |
6de22619 JW |
2184 | /* |
2185 | * The RCU lock is held throughout the transaction. The fast | |
2186 | * path can get away without acquiring the memcg->move_lock | |
2187 | * because page moving starts with an RCU grace period. | |
739f79fc | 2188 | */ |
d7365e78 JW |
2189 | rcu_read_lock(); |
2190 | ||
2191 | if (mem_cgroup_disabled()) | |
1c824a68 | 2192 | return; |
89c06bd5 | 2193 | again: |
f70ad448 | 2194 | memcg = folio_memcg(folio); |
29833315 | 2195 | if (unlikely(!memcg)) |
1c824a68 | 2196 | return; |
d7365e78 | 2197 | |
20ad50d6 AS |
2198 | #ifdef CONFIG_PROVE_LOCKING |
2199 | local_irq_save(flags); | |
2200 | might_lock(&memcg->move_lock); | |
2201 | local_irq_restore(flags); | |
2202 | #endif | |
2203 | ||
bdcbb659 | 2204 | if (atomic_read(&memcg->moving_account) <= 0) |
1c824a68 | 2205 | return; |
89c06bd5 | 2206 | |
6de22619 | 2207 | spin_lock_irqsave(&memcg->move_lock, flags); |
f70ad448 | 2208 | if (memcg != folio_memcg(folio)) { |
6de22619 | 2209 | spin_unlock_irqrestore(&memcg->move_lock, flags); |
89c06bd5 KH |
2210 | goto again; |
2211 | } | |
6de22619 JW |
2212 | |
2213 | /* | |
1c824a68 JW |
2214 | * When charge migration first begins, we can have multiple |
2215 | * critical sections holding the fast-path RCU lock and one | |
2216 | * holding the slowpath move_lock. Track the task who has the | |
6c77b607 | 2217 | * move_lock for folio_memcg_unlock(). |
6de22619 JW |
2218 | */ |
2219 | memcg->move_lock_task = current; | |
2220 | memcg->move_lock_flags = flags; | |
89c06bd5 | 2221 | } |
f70ad448 | 2222 | |
f70ad448 | 2223 | static void __folio_memcg_unlock(struct mem_cgroup *memcg) |
89c06bd5 | 2224 | { |
6de22619 JW |
2225 | if (memcg && memcg->move_lock_task == current) { |
2226 | unsigned long flags = memcg->move_lock_flags; | |
2227 | ||
2228 | memcg->move_lock_task = NULL; | |
2229 | memcg->move_lock_flags = 0; | |
2230 | ||
2231 | spin_unlock_irqrestore(&memcg->move_lock, flags); | |
2232 | } | |
89c06bd5 | 2233 | |
d7365e78 | 2234 | rcu_read_unlock(); |
89c06bd5 | 2235 | } |
739f79fc JW |
2236 | |
2237 | /** | |
f70ad448 MWO |
2238 | * folio_memcg_unlock - Release the binding between a folio and its memcg. |
2239 | * @folio: The folio. | |
2240 | * | |
2241 | * This releases the binding created by folio_memcg_lock(). This does | |
2242 | * not change the accounting of this folio to its memcg, but it does | |
2243 | * permit others to change it. | |
739f79fc | 2244 | */ |
f70ad448 | 2245 | void folio_memcg_unlock(struct folio *folio) |
739f79fc | 2246 | { |
f70ad448 MWO |
2247 | __folio_memcg_unlock(folio_memcg(folio)); |
2248 | } | |
9da7b521 | 2249 | |
fead2b86 | 2250 | struct memcg_stock_pcp { |
56751146 | 2251 | local_lock_t stock_lock; |
fead2b86 MH |
2252 | struct mem_cgroup *cached; /* this never be root cgroup */ |
2253 | unsigned int nr_pages; | |
2254 | ||
bf4f0599 RG |
2255 | #ifdef CONFIG_MEMCG_KMEM |
2256 | struct obj_cgroup *cached_objcg; | |
68ac5b3c | 2257 | struct pglist_data *cached_pgdat; |
bf4f0599 | 2258 | unsigned int nr_bytes; |
68ac5b3c WL |
2259 | int nr_slab_reclaimable_b; |
2260 | int nr_slab_unreclaimable_b; | |
bf4f0599 RG |
2261 | #endif |
2262 | ||
cdec2e42 | 2263 | struct work_struct work; |
26fe6168 | 2264 | unsigned long flags; |
a0db00fc | 2265 | #define FLUSHING_CACHED_CHARGE 0 |
cdec2e42 | 2266 | }; |
56751146 SAS |
2267 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock) = { |
2268 | .stock_lock = INIT_LOCAL_LOCK(stock_lock), | |
2269 | }; | |
9f50fad6 | 2270 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 | 2271 | |
bf4f0599 | 2272 | #ifdef CONFIG_MEMCG_KMEM |
56751146 | 2273 | static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock); |
bf4f0599 RG |
2274 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, |
2275 | struct mem_cgroup *root_memcg); | |
a8c49af3 | 2276 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages); |
bf4f0599 RG |
2277 | |
2278 | #else | |
56751146 | 2279 | static inline struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) |
bf4f0599 | 2280 | { |
56751146 | 2281 | return NULL; |
bf4f0599 RG |
2282 | } |
2283 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, | |
2284 | struct mem_cgroup *root_memcg) | |
2285 | { | |
2286 | return false; | |
2287 | } | |
a8c49af3 YA |
2288 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) |
2289 | { | |
2290 | } | |
bf4f0599 RG |
2291 | #endif |
2292 | ||
a0956d54 SS |
2293 | /** |
2294 | * consume_stock: Try to consume stocked charge on this cpu. | |
2295 | * @memcg: memcg to consume from. | |
2296 | * @nr_pages: how many pages to charge. | |
2297 | * | |
2298 | * The charges will only happen if @memcg matches the current cpu's memcg | |
2299 | * stock, and at least @nr_pages are available in that stock. Failure to | |
2300 | * service an allocation will refill the stock. | |
2301 | * | |
2302 | * returns true if successful, false otherwise. | |
cdec2e42 | 2303 | */ |
a0956d54 | 2304 | static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
2305 | { |
2306 | struct memcg_stock_pcp *stock; | |
db2ba40c | 2307 | unsigned long flags; |
3e32cb2e | 2308 | bool ret = false; |
cdec2e42 | 2309 | |
a983b5eb | 2310 | if (nr_pages > MEMCG_CHARGE_BATCH) |
3e32cb2e | 2311 | return ret; |
a0956d54 | 2312 | |
56751146 | 2313 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
db2ba40c JW |
2314 | |
2315 | stock = this_cpu_ptr(&memcg_stock); | |
f785a8f2 | 2316 | if (memcg == READ_ONCE(stock->cached) && stock->nr_pages >= nr_pages) { |
a0956d54 | 2317 | stock->nr_pages -= nr_pages; |
3e32cb2e JW |
2318 | ret = true; |
2319 | } | |
db2ba40c | 2320 | |
56751146 | 2321 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
db2ba40c | 2322 | |
cdec2e42 KH |
2323 | return ret; |
2324 | } | |
2325 | ||
2326 | /* | |
3e32cb2e | 2327 | * Returns stocks cached in percpu and reset cached information. |
cdec2e42 KH |
2328 | */ |
2329 | static void drain_stock(struct memcg_stock_pcp *stock) | |
2330 | { | |
f785a8f2 | 2331 | struct mem_cgroup *old = READ_ONCE(stock->cached); |
cdec2e42 | 2332 | |
1a3e1f40 JW |
2333 | if (!old) |
2334 | return; | |
2335 | ||
11c9ea4e | 2336 | if (stock->nr_pages) { |
3e32cb2e | 2337 | page_counter_uncharge(&old->memory, stock->nr_pages); |
7941d214 | 2338 | if (do_memsw_account()) |
3e32cb2e | 2339 | page_counter_uncharge(&old->memsw, stock->nr_pages); |
11c9ea4e | 2340 | stock->nr_pages = 0; |
cdec2e42 | 2341 | } |
1a3e1f40 JW |
2342 | |
2343 | css_put(&old->css); | |
f785a8f2 | 2344 | WRITE_ONCE(stock->cached, NULL); |
cdec2e42 KH |
2345 | } |
2346 | ||
cdec2e42 KH |
2347 | static void drain_local_stock(struct work_struct *dummy) |
2348 | { | |
db2ba40c | 2349 | struct memcg_stock_pcp *stock; |
56751146 | 2350 | struct obj_cgroup *old = NULL; |
db2ba40c JW |
2351 | unsigned long flags; |
2352 | ||
72f0184c | 2353 | /* |
5c49cf9a MH |
2354 | * The only protection from cpu hotplug (memcg_hotplug_cpu_dead) vs. |
2355 | * drain_stock races is that we always operate on local CPU stock | |
2356 | * here with IRQ disabled | |
72f0184c | 2357 | */ |
56751146 | 2358 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
db2ba40c JW |
2359 | |
2360 | stock = this_cpu_ptr(&memcg_stock); | |
56751146 | 2361 | old = drain_obj_stock(stock); |
cdec2e42 | 2362 | drain_stock(stock); |
26fe6168 | 2363 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
db2ba40c | 2364 | |
56751146 SAS |
2365 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
2366 | if (old) | |
2367 | obj_cgroup_put(old); | |
cdec2e42 KH |
2368 | } |
2369 | ||
2370 | /* | |
3e32cb2e | 2371 | * Cache charges(val) to local per_cpu area. |
320cc51d | 2372 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 2373 | */ |
af9a3b69 | 2374 | static void __refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 | 2375 | { |
db2ba40c | 2376 | struct memcg_stock_pcp *stock; |
cdec2e42 | 2377 | |
db2ba40c | 2378 | stock = this_cpu_ptr(&memcg_stock); |
f785a8f2 | 2379 | if (READ_ONCE(stock->cached) != memcg) { /* reset if necessary */ |
cdec2e42 | 2380 | drain_stock(stock); |
1a3e1f40 | 2381 | css_get(&memcg->css); |
f785a8f2 | 2382 | WRITE_ONCE(stock->cached, memcg); |
cdec2e42 | 2383 | } |
11c9ea4e | 2384 | stock->nr_pages += nr_pages; |
db2ba40c | 2385 | |
a983b5eb | 2386 | if (stock->nr_pages > MEMCG_CHARGE_BATCH) |
475d0487 | 2387 | drain_stock(stock); |
af9a3b69 JW |
2388 | } |
2389 | ||
2390 | static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) | |
2391 | { | |
2392 | unsigned long flags; | |
475d0487 | 2393 | |
56751146 | 2394 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
af9a3b69 | 2395 | __refill_stock(memcg, nr_pages); |
56751146 | 2396 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
cdec2e42 KH |
2397 | } |
2398 | ||
2399 | /* | |
c0ff4b85 | 2400 | * Drains all per-CPU charge caches for given root_memcg resp. subtree |
6d3d6aa2 | 2401 | * of the hierarchy under it. |
cdec2e42 | 2402 | */ |
6d3d6aa2 | 2403 | static void drain_all_stock(struct mem_cgroup *root_memcg) |
cdec2e42 | 2404 | { |
26fe6168 | 2405 | int cpu, curcpu; |
d38144b7 | 2406 | |
6d3d6aa2 JW |
2407 | /* If someone's already draining, avoid adding running more workers. */ |
2408 | if (!mutex_trylock(&percpu_charge_mutex)) | |
2409 | return; | |
72f0184c MH |
2410 | /* |
2411 | * Notify other cpus that system-wide "drain" is running | |
2412 | * We do not care about races with the cpu hotplug because cpu down | |
2413 | * as well as workers from this path always operate on the local | |
2414 | * per-cpu data. CPU up doesn't touch memcg_stock at all. | |
2415 | */ | |
0790ed62 SAS |
2416 | migrate_disable(); |
2417 | curcpu = smp_processor_id(); | |
cdec2e42 KH |
2418 | for_each_online_cpu(cpu) { |
2419 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
c0ff4b85 | 2420 | struct mem_cgroup *memcg; |
e1a366be | 2421 | bool flush = false; |
26fe6168 | 2422 | |
e1a366be | 2423 | rcu_read_lock(); |
f785a8f2 | 2424 | memcg = READ_ONCE(stock->cached); |
e1a366be RG |
2425 | if (memcg && stock->nr_pages && |
2426 | mem_cgroup_is_descendant(memcg, root_memcg)) | |
2427 | flush = true; | |
27fb0956 | 2428 | else if (obj_stock_flush_required(stock, root_memcg)) |
bf4f0599 | 2429 | flush = true; |
e1a366be RG |
2430 | rcu_read_unlock(); |
2431 | ||
2432 | if (flush && | |
2433 | !test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { | |
d1a05b69 MH |
2434 | if (cpu == curcpu) |
2435 | drain_local_stock(&stock->work); | |
6a792697 | 2436 | else if (!cpu_is_isolated(cpu)) |
d1a05b69 MH |
2437 | schedule_work_on(cpu, &stock->work); |
2438 | } | |
cdec2e42 | 2439 | } |
0790ed62 | 2440 | migrate_enable(); |
9f50fad6 | 2441 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2442 | } |
2443 | ||
2cd21c89 JW |
2444 | static int memcg_hotplug_cpu_dead(unsigned int cpu) |
2445 | { | |
2446 | struct memcg_stock_pcp *stock; | |
a3d4c05a | 2447 | |
2cd21c89 JW |
2448 | stock = &per_cpu(memcg_stock, cpu); |
2449 | drain_stock(stock); | |
a3d4c05a | 2450 | |
308167fc | 2451 | return 0; |
cdec2e42 KH |
2452 | } |
2453 | ||
b3ff9291 CD |
2454 | static unsigned long reclaim_high(struct mem_cgroup *memcg, |
2455 | unsigned int nr_pages, | |
2456 | gfp_t gfp_mask) | |
f7e1cb6e | 2457 | { |
b3ff9291 CD |
2458 | unsigned long nr_reclaimed = 0; |
2459 | ||
f7e1cb6e | 2460 | do { |
e22c6ed9 JW |
2461 | unsigned long pflags; |
2462 | ||
d1663a90 JK |
2463 | if (page_counter_read(&memcg->memory) <= |
2464 | READ_ONCE(memcg->memory.high)) | |
f7e1cb6e | 2465 | continue; |
e22c6ed9 | 2466 | |
e27be240 | 2467 | memcg_memory_event(memcg, MEMCG_HIGH); |
e22c6ed9 JW |
2468 | |
2469 | psi_memstall_enter(&pflags); | |
b3ff9291 | 2470 | nr_reclaimed += try_to_free_mem_cgroup_pages(memcg, nr_pages, |
73b73bac | 2471 | gfp_mask, |
55ab834a | 2472 | MEMCG_RECLAIM_MAY_SWAP); |
e22c6ed9 | 2473 | psi_memstall_leave(&pflags); |
4bf17307 CD |
2474 | } while ((memcg = parent_mem_cgroup(memcg)) && |
2475 | !mem_cgroup_is_root(memcg)); | |
b3ff9291 CD |
2476 | |
2477 | return nr_reclaimed; | |
f7e1cb6e JW |
2478 | } |
2479 | ||
2480 | static void high_work_func(struct work_struct *work) | |
2481 | { | |
2482 | struct mem_cgroup *memcg; | |
2483 | ||
2484 | memcg = container_of(work, struct mem_cgroup, high_work); | |
a983b5eb | 2485 | reclaim_high(memcg, MEMCG_CHARGE_BATCH, GFP_KERNEL); |
f7e1cb6e JW |
2486 | } |
2487 | ||
0e4b01df CD |
2488 | /* |
2489 | * Clamp the maximum sleep time per allocation batch to 2 seconds. This is | |
2490 | * enough to still cause a significant slowdown in most cases, while still | |
2491 | * allowing diagnostics and tracing to proceed without becoming stuck. | |
2492 | */ | |
2493 | #define MEMCG_MAX_HIGH_DELAY_JIFFIES (2UL*HZ) | |
2494 | ||
2495 | /* | |
2496 | * When calculating the delay, we use these either side of the exponentiation to | |
2497 | * maintain precision and scale to a reasonable number of jiffies (see the table | |
2498 | * below. | |
2499 | * | |
2500 | * - MEMCG_DELAY_PRECISION_SHIFT: Extra precision bits while translating the | |
2501 | * overage ratio to a delay. | |
ac5ddd0f | 2502 | * - MEMCG_DELAY_SCALING_SHIFT: The number of bits to scale down the |
0e4b01df CD |
2503 | * proposed penalty in order to reduce to a reasonable number of jiffies, and |
2504 | * to produce a reasonable delay curve. | |
2505 | * | |
2506 | * MEMCG_DELAY_SCALING_SHIFT just happens to be a number that produces a | |
2507 | * reasonable delay curve compared to precision-adjusted overage, not | |
2508 | * penalising heavily at first, but still making sure that growth beyond the | |
2509 | * limit penalises misbehaviour cgroups by slowing them down exponentially. For | |
2510 | * example, with a high of 100 megabytes: | |
2511 | * | |
2512 | * +-------+------------------------+ | |
2513 | * | usage | time to allocate in ms | | |
2514 | * +-------+------------------------+ | |
2515 | * | 100M | 0 | | |
2516 | * | 101M | 6 | | |
2517 | * | 102M | 25 | | |
2518 | * | 103M | 57 | | |
2519 | * | 104M | 102 | | |
2520 | * | 105M | 159 | | |
2521 | * | 106M | 230 | | |
2522 | * | 107M | 313 | | |
2523 | * | 108M | 409 | | |
2524 | * | 109M | 518 | | |
2525 | * | 110M | 639 | | |
2526 | * | 111M | 774 | | |
2527 | * | 112M | 921 | | |
2528 | * | 113M | 1081 | | |
2529 | * | 114M | 1254 | | |
2530 | * | 115M | 1439 | | |
2531 | * | 116M | 1638 | | |
2532 | * | 117M | 1849 | | |
2533 | * | 118M | 2000 | | |
2534 | * | 119M | 2000 | | |
2535 | * | 120M | 2000 | | |
2536 | * +-------+------------------------+ | |
2537 | */ | |
2538 | #define MEMCG_DELAY_PRECISION_SHIFT 20 | |
2539 | #define MEMCG_DELAY_SCALING_SHIFT 14 | |
2540 | ||
8a5dbc65 | 2541 | static u64 calculate_overage(unsigned long usage, unsigned long high) |
b23afb93 | 2542 | { |
8a5dbc65 | 2543 | u64 overage; |
b23afb93 | 2544 | |
8a5dbc65 JK |
2545 | if (usage <= high) |
2546 | return 0; | |
e26733e0 | 2547 | |
8a5dbc65 JK |
2548 | /* |
2549 | * Prevent division by 0 in overage calculation by acting as if | |
2550 | * it was a threshold of 1 page | |
2551 | */ | |
2552 | high = max(high, 1UL); | |
9b8b1754 | 2553 | |
8a5dbc65 JK |
2554 | overage = usage - high; |
2555 | overage <<= MEMCG_DELAY_PRECISION_SHIFT; | |
2556 | return div64_u64(overage, high); | |
2557 | } | |
e26733e0 | 2558 | |
8a5dbc65 JK |
2559 | static u64 mem_find_max_overage(struct mem_cgroup *memcg) |
2560 | { | |
2561 | u64 overage, max_overage = 0; | |
e26733e0 | 2562 | |
8a5dbc65 JK |
2563 | do { |
2564 | overage = calculate_overage(page_counter_read(&memcg->memory), | |
d1663a90 | 2565 | READ_ONCE(memcg->memory.high)); |
8a5dbc65 | 2566 | max_overage = max(overage, max_overage); |
e26733e0 CD |
2567 | } while ((memcg = parent_mem_cgroup(memcg)) && |
2568 | !mem_cgroup_is_root(memcg)); | |
2569 | ||
8a5dbc65 JK |
2570 | return max_overage; |
2571 | } | |
2572 | ||
4b82ab4f JK |
2573 | static u64 swap_find_max_overage(struct mem_cgroup *memcg) |
2574 | { | |
2575 | u64 overage, max_overage = 0; | |
2576 | ||
2577 | do { | |
2578 | overage = calculate_overage(page_counter_read(&memcg->swap), | |
2579 | READ_ONCE(memcg->swap.high)); | |
2580 | if (overage) | |
2581 | memcg_memory_event(memcg, MEMCG_SWAP_HIGH); | |
2582 | max_overage = max(overage, max_overage); | |
2583 | } while ((memcg = parent_mem_cgroup(memcg)) && | |
2584 | !mem_cgroup_is_root(memcg)); | |
2585 | ||
2586 | return max_overage; | |
2587 | } | |
2588 | ||
8a5dbc65 JK |
2589 | /* |
2590 | * Get the number of jiffies that we should penalise a mischievous cgroup which | |
2591 | * is exceeding its memory.high by checking both it and its ancestors. | |
2592 | */ | |
2593 | static unsigned long calculate_high_delay(struct mem_cgroup *memcg, | |
2594 | unsigned int nr_pages, | |
2595 | u64 max_overage) | |
2596 | { | |
2597 | unsigned long penalty_jiffies; | |
2598 | ||
e26733e0 CD |
2599 | if (!max_overage) |
2600 | return 0; | |
0e4b01df CD |
2601 | |
2602 | /* | |
0e4b01df CD |
2603 | * We use overage compared to memory.high to calculate the number of |
2604 | * jiffies to sleep (penalty_jiffies). Ideally this value should be | |
2605 | * fairly lenient on small overages, and increasingly harsh when the | |
2606 | * memcg in question makes it clear that it has no intention of stopping | |
2607 | * its crazy behaviour, so we exponentially increase the delay based on | |
2608 | * overage amount. | |
2609 | */ | |
e26733e0 CD |
2610 | penalty_jiffies = max_overage * max_overage * HZ; |
2611 | penalty_jiffies >>= MEMCG_DELAY_PRECISION_SHIFT; | |
2612 | penalty_jiffies >>= MEMCG_DELAY_SCALING_SHIFT; | |
0e4b01df CD |
2613 | |
2614 | /* | |
2615 | * Factor in the task's own contribution to the overage, such that four | |
2616 | * N-sized allocations are throttled approximately the same as one | |
2617 | * 4N-sized allocation. | |
2618 | * | |
2619 | * MEMCG_CHARGE_BATCH pages is nominal, so work out how much smaller or | |
2620 | * larger the current charge patch is than that. | |
2621 | */ | |
ff144e69 | 2622 | return penalty_jiffies * nr_pages / MEMCG_CHARGE_BATCH; |
e26733e0 CD |
2623 | } |
2624 | ||
2625 | /* | |
63fd3270 JW |
2626 | * Reclaims memory over the high limit. Called directly from |
2627 | * try_charge() (context permitting), as well as from the userland | |
2628 | * return path where reclaim is always able to block. | |
e26733e0 | 2629 | */ |
9ea9cb00 | 2630 | void mem_cgroup_handle_over_high(gfp_t gfp_mask) |
e26733e0 CD |
2631 | { |
2632 | unsigned long penalty_jiffies; | |
2633 | unsigned long pflags; | |
b3ff9291 | 2634 | unsigned long nr_reclaimed; |
e26733e0 | 2635 | unsigned int nr_pages = current->memcg_nr_pages_over_high; |
d977aa93 | 2636 | int nr_retries = MAX_RECLAIM_RETRIES; |
e26733e0 | 2637 | struct mem_cgroup *memcg; |
b3ff9291 | 2638 | bool in_retry = false; |
e26733e0 CD |
2639 | |
2640 | if (likely(!nr_pages)) | |
2641 | return; | |
2642 | ||
2643 | memcg = get_mem_cgroup_from_mm(current->mm); | |
e26733e0 CD |
2644 | current->memcg_nr_pages_over_high = 0; |
2645 | ||
b3ff9291 | 2646 | retry_reclaim: |
63fd3270 JW |
2647 | /* |
2648 | * Bail if the task is already exiting. Unlike memory.max, | |
2649 | * memory.high enforcement isn't as strict, and there is no | |
2650 | * OOM killer involved, which means the excess could already | |
2651 | * be much bigger (and still growing) than it could for | |
2652 | * memory.max; the dying task could get stuck in fruitless | |
2653 | * reclaim for a long time, which isn't desirable. | |
2654 | */ | |
2655 | if (task_is_dying()) | |
2656 | goto out; | |
2657 | ||
b3ff9291 CD |
2658 | /* |
2659 | * The allocating task should reclaim at least the batch size, but for | |
2660 | * subsequent retries we only want to do what's necessary to prevent oom | |
2661 | * or breaching resource isolation. | |
2662 | * | |
2663 | * This is distinct from memory.max or page allocator behaviour because | |
2664 | * memory.high is currently batched, whereas memory.max and the page | |
2665 | * allocator run every time an allocation is made. | |
2666 | */ | |
2667 | nr_reclaimed = reclaim_high(memcg, | |
2668 | in_retry ? SWAP_CLUSTER_MAX : nr_pages, | |
9ea9cb00 | 2669 | gfp_mask); |
b3ff9291 | 2670 | |
e26733e0 CD |
2671 | /* |
2672 | * memory.high is breached and reclaim is unable to keep up. Throttle | |
2673 | * allocators proactively to slow down excessive growth. | |
2674 | */ | |
8a5dbc65 JK |
2675 | penalty_jiffies = calculate_high_delay(memcg, nr_pages, |
2676 | mem_find_max_overage(memcg)); | |
0e4b01df | 2677 | |
4b82ab4f JK |
2678 | penalty_jiffies += calculate_high_delay(memcg, nr_pages, |
2679 | swap_find_max_overage(memcg)); | |
2680 | ||
ff144e69 JK |
2681 | /* |
2682 | * Clamp the max delay per usermode return so as to still keep the | |
2683 | * application moving forwards and also permit diagnostics, albeit | |
2684 | * extremely slowly. | |
2685 | */ | |
2686 | penalty_jiffies = min(penalty_jiffies, MEMCG_MAX_HIGH_DELAY_JIFFIES); | |
2687 | ||
0e4b01df CD |
2688 | /* |
2689 | * Don't sleep if the amount of jiffies this memcg owes us is so low | |
2690 | * that it's not even worth doing, in an attempt to be nice to those who | |
2691 | * go only a small amount over their memory.high value and maybe haven't | |
2692 | * been aggressively reclaimed enough yet. | |
2693 | */ | |
2694 | if (penalty_jiffies <= HZ / 100) | |
2695 | goto out; | |
2696 | ||
b3ff9291 CD |
2697 | /* |
2698 | * If reclaim is making forward progress but we're still over | |
2699 | * memory.high, we want to encourage that rather than doing allocator | |
2700 | * throttling. | |
2701 | */ | |
2702 | if (nr_reclaimed || nr_retries--) { | |
2703 | in_retry = true; | |
2704 | goto retry_reclaim; | |
2705 | } | |
2706 | ||
0e4b01df | 2707 | /* |
63fd3270 JW |
2708 | * Reclaim didn't manage to push usage below the limit, slow |
2709 | * this allocating task down. | |
2710 | * | |
0e4b01df CD |
2711 | * If we exit early, we're guaranteed to die (since |
2712 | * schedule_timeout_killable sets TASK_KILLABLE). This means we don't | |
2713 | * need to account for any ill-begotten jiffies to pay them off later. | |
2714 | */ | |
2715 | psi_memstall_enter(&pflags); | |
2716 | schedule_timeout_killable(penalty_jiffies); | |
2717 | psi_memstall_leave(&pflags); | |
2718 | ||
2719 | out: | |
2720 | css_put(&memcg->css); | |
b23afb93 TH |
2721 | } |
2722 | ||
c5c8b16b MS |
2723 | static int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask, |
2724 | unsigned int nr_pages) | |
8a9f3ccd | 2725 | { |
a983b5eb | 2726 | unsigned int batch = max(MEMCG_CHARGE_BATCH, nr_pages); |
d977aa93 | 2727 | int nr_retries = MAX_RECLAIM_RETRIES; |
6539cc05 | 2728 | struct mem_cgroup *mem_over_limit; |
3e32cb2e | 2729 | struct page_counter *counter; |
6539cc05 | 2730 | unsigned long nr_reclaimed; |
a4ebf1b6 | 2731 | bool passed_oom = false; |
73b73bac | 2732 | unsigned int reclaim_options = MEMCG_RECLAIM_MAY_SWAP; |
b70a2a21 | 2733 | bool drained = false; |
d6e103a7 | 2734 | bool raised_max_event = false; |
e22c6ed9 | 2735 | unsigned long pflags; |
a636b327 | 2736 | |
6539cc05 | 2737 | retry: |
b6b6cc72 | 2738 | if (consume_stock(memcg, nr_pages)) |
10d53c74 | 2739 | return 0; |
8a9f3ccd | 2740 | |
7941d214 | 2741 | if (!do_memsw_account() || |
6071ca52 JW |
2742 | page_counter_try_charge(&memcg->memsw, batch, &counter)) { |
2743 | if (page_counter_try_charge(&memcg->memory, batch, &counter)) | |
6539cc05 | 2744 | goto done_restock; |
7941d214 | 2745 | if (do_memsw_account()) |
3e32cb2e JW |
2746 | page_counter_uncharge(&memcg->memsw, batch); |
2747 | mem_over_limit = mem_cgroup_from_counter(counter, memory); | |
3fbe7244 | 2748 | } else { |
3e32cb2e | 2749 | mem_over_limit = mem_cgroup_from_counter(counter, memsw); |
73b73bac | 2750 | reclaim_options &= ~MEMCG_RECLAIM_MAY_SWAP; |
3fbe7244 | 2751 | } |
7a81b88c | 2752 | |
6539cc05 JW |
2753 | if (batch > nr_pages) { |
2754 | batch = nr_pages; | |
2755 | goto retry; | |
2756 | } | |
6d61ef40 | 2757 | |
89a28483 JW |
2758 | /* |
2759 | * Prevent unbounded recursion when reclaim operations need to | |
2760 | * allocate memory. This might exceed the limits temporarily, | |
2761 | * but we prefer facilitating memory reclaim and getting back | |
2762 | * under the limit over triggering OOM kills in these cases. | |
2763 | */ | |
2764 | if (unlikely(current->flags & PF_MEMALLOC)) | |
2765 | goto force; | |
2766 | ||
06b078fc JW |
2767 | if (unlikely(task_in_memcg_oom(current))) |
2768 | goto nomem; | |
2769 | ||
d0164adc | 2770 | if (!gfpflags_allow_blocking(gfp_mask)) |
6539cc05 | 2771 | goto nomem; |
4b534334 | 2772 | |
e27be240 | 2773 | memcg_memory_event(mem_over_limit, MEMCG_MAX); |
d6e103a7 | 2774 | raised_max_event = true; |
241994ed | 2775 | |
e22c6ed9 | 2776 | psi_memstall_enter(&pflags); |
b70a2a21 | 2777 | nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages, |
55ab834a | 2778 | gfp_mask, reclaim_options); |
e22c6ed9 | 2779 | psi_memstall_leave(&pflags); |
6539cc05 | 2780 | |
61e02c74 | 2781 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
6539cc05 | 2782 | goto retry; |
28c34c29 | 2783 | |
b70a2a21 | 2784 | if (!drained) { |
6d3d6aa2 | 2785 | drain_all_stock(mem_over_limit); |
b70a2a21 JW |
2786 | drained = true; |
2787 | goto retry; | |
2788 | } | |
2789 | ||
28c34c29 JW |
2790 | if (gfp_mask & __GFP_NORETRY) |
2791 | goto nomem; | |
6539cc05 JW |
2792 | /* |
2793 | * Even though the limit is exceeded at this point, reclaim | |
2794 | * may have been able to free some pages. Retry the charge | |
2795 | * before killing the task. | |
2796 | * | |
2797 | * Only for regular pages, though: huge pages are rather | |
2798 | * unlikely to succeed so close to the limit, and we fall back | |
2799 | * to regular pages anyway in case of failure. | |
2800 | */ | |
61e02c74 | 2801 | if (nr_reclaimed && nr_pages <= (1 << PAGE_ALLOC_COSTLY_ORDER)) |
6539cc05 JW |
2802 | goto retry; |
2803 | /* | |
2804 | * At task move, charge accounts can be doubly counted. So, it's | |
2805 | * better to wait until the end of task_move if something is going on. | |
2806 | */ | |
2807 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2808 | goto retry; | |
2809 | ||
9b130619 JW |
2810 | if (nr_retries--) |
2811 | goto retry; | |
2812 | ||
38d38493 | 2813 | if (gfp_mask & __GFP_RETRY_MAYFAIL) |
29ef680a MH |
2814 | goto nomem; |
2815 | ||
a4ebf1b6 VA |
2816 | /* Avoid endless loop for tasks bypassed by the oom killer */ |
2817 | if (passed_oom && task_is_dying()) | |
2818 | goto nomem; | |
6539cc05 | 2819 | |
29ef680a MH |
2820 | /* |
2821 | * keep retrying as long as the memcg oom killer is able to make | |
2822 | * a forward progress or bypass the charge if the oom killer | |
2823 | * couldn't make any progress. | |
2824 | */ | |
becdf89d SB |
2825 | if (mem_cgroup_oom(mem_over_limit, gfp_mask, |
2826 | get_order(nr_pages * PAGE_SIZE))) { | |
a4ebf1b6 | 2827 | passed_oom = true; |
d977aa93 | 2828 | nr_retries = MAX_RECLAIM_RETRIES; |
29ef680a | 2829 | goto retry; |
29ef680a | 2830 | } |
7a81b88c | 2831 | nomem: |
1461e8c2 SB |
2832 | /* |
2833 | * Memcg doesn't have a dedicated reserve for atomic | |
2834 | * allocations. But like the global atomic pool, we need to | |
2835 | * put the burden of reclaim on regular allocation requests | |
2836 | * and let these go through as privileged allocations. | |
2837 | */ | |
2838 | if (!(gfp_mask & (__GFP_NOFAIL | __GFP_HIGH))) | |
3168ecbe | 2839 | return -ENOMEM; |
10d53c74 | 2840 | force: |
d6e103a7 RG |
2841 | /* |
2842 | * If the allocation has to be enforced, don't forget to raise | |
2843 | * a MEMCG_MAX event. | |
2844 | */ | |
2845 | if (!raised_max_event) | |
2846 | memcg_memory_event(mem_over_limit, MEMCG_MAX); | |
2847 | ||
10d53c74 TH |
2848 | /* |
2849 | * The allocation either can't fail or will lead to more memory | |
2850 | * being freed very soon. Allow memory usage go over the limit | |
2851 | * temporarily by force charging it. | |
2852 | */ | |
2853 | page_counter_charge(&memcg->memory, nr_pages); | |
7941d214 | 2854 | if (do_memsw_account()) |
10d53c74 | 2855 | page_counter_charge(&memcg->memsw, nr_pages); |
10d53c74 TH |
2856 | |
2857 | return 0; | |
6539cc05 JW |
2858 | |
2859 | done_restock: | |
2860 | if (batch > nr_pages) | |
2861 | refill_stock(memcg, batch - nr_pages); | |
b23afb93 | 2862 | |
241994ed | 2863 | /* |
b23afb93 TH |
2864 | * If the hierarchy is above the normal consumption range, schedule |
2865 | * reclaim on returning to userland. We can perform reclaim here | |
71baba4b | 2866 | * if __GFP_RECLAIM but let's always punt for simplicity and so that |
b23afb93 TH |
2867 | * GFP_KERNEL can consistently be used during reclaim. @memcg is |
2868 | * not recorded as it most likely matches current's and won't | |
2869 | * change in the meantime. As high limit is checked again before | |
2870 | * reclaim, the cost of mismatch is negligible. | |
241994ed JW |
2871 | */ |
2872 | do { | |
4b82ab4f JK |
2873 | bool mem_high, swap_high; |
2874 | ||
2875 | mem_high = page_counter_read(&memcg->memory) > | |
2876 | READ_ONCE(memcg->memory.high); | |
2877 | swap_high = page_counter_read(&memcg->swap) > | |
2878 | READ_ONCE(memcg->swap.high); | |
2879 | ||
2880 | /* Don't bother a random interrupted task */ | |
086f694a | 2881 | if (!in_task()) { |
4b82ab4f | 2882 | if (mem_high) { |
f7e1cb6e JW |
2883 | schedule_work(&memcg->high_work); |
2884 | break; | |
2885 | } | |
4b82ab4f JK |
2886 | continue; |
2887 | } | |
2888 | ||
2889 | if (mem_high || swap_high) { | |
2890 | /* | |
2891 | * The allocating tasks in this cgroup will need to do | |
2892 | * reclaim or be throttled to prevent further growth | |
2893 | * of the memory or swap footprints. | |
2894 | * | |
2895 | * Target some best-effort fairness between the tasks, | |
2896 | * and distribute reclaim work and delay penalties | |
2897 | * based on how much each task is actually allocating. | |
2898 | */ | |
9516a18a | 2899 | current->memcg_nr_pages_over_high += batch; |
b23afb93 TH |
2900 | set_notify_resume(current); |
2901 | break; | |
2902 | } | |
241994ed | 2903 | } while ((memcg = parent_mem_cgroup(memcg))); |
10d53c74 | 2904 | |
63fd3270 JW |
2905 | /* |
2906 | * Reclaim is set up above to be called from the userland | |
2907 | * return path. But also attempt synchronous reclaim to avoid | |
2908 | * excessive overrun while the task is still inside the | |
2909 | * kernel. If this is successful, the return path will see it | |
2910 | * when it rechecks the overage and simply bail out. | |
2911 | */ | |
c9afe31e SB |
2912 | if (current->memcg_nr_pages_over_high > MEMCG_CHARGE_BATCH && |
2913 | !(current->flags & PF_MEMALLOC) && | |
63fd3270 | 2914 | gfpflags_allow_blocking(gfp_mask)) |
9ea9cb00 | 2915 | mem_cgroup_handle_over_high(gfp_mask); |
10d53c74 | 2916 | return 0; |
7a81b88c | 2917 | } |
8a9f3ccd | 2918 | |
c5c8b16b MS |
2919 | static inline int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, |
2920 | unsigned int nr_pages) | |
2921 | { | |
2922 | if (mem_cgroup_is_root(memcg)) | |
2923 | return 0; | |
2924 | ||
2925 | return try_charge_memcg(memcg, gfp_mask, nr_pages); | |
2926 | } | |
2927 | ||
4b569387 NP |
2928 | /** |
2929 | * mem_cgroup_cancel_charge() - cancel an uncommitted try_charge() call. | |
2930 | * @memcg: memcg previously charged. | |
2931 | * @nr_pages: number of pages previously charged. | |
2932 | */ | |
2933 | void mem_cgroup_cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) | |
a3032a2c | 2934 | { |
ce00a967 JW |
2935 | if (mem_cgroup_is_root(memcg)) |
2936 | return; | |
2937 | ||
3e32cb2e | 2938 | page_counter_uncharge(&memcg->memory, nr_pages); |
7941d214 | 2939 | if (do_memsw_account()) |
3e32cb2e | 2940 | page_counter_uncharge(&memcg->memsw, nr_pages); |
d01dd17f KH |
2941 | } |
2942 | ||
118f2875 | 2943 | static void commit_charge(struct folio *folio, struct mem_cgroup *memcg) |
0a31bc97 | 2944 | { |
118f2875 | 2945 | VM_BUG_ON_FOLIO(folio_memcg(folio), folio); |
0a31bc97 | 2946 | /* |
a5eb011a | 2947 | * Any of the following ensures page's memcg stability: |
0a31bc97 | 2948 | * |
a0b5b414 JW |
2949 | * - the page lock |
2950 | * - LRU isolation | |
6c77b607 | 2951 | * - folio_memcg_lock() |
a0b5b414 | 2952 | * - exclusive reference |
018ee47f | 2953 | * - mem_cgroup_trylock_pages() |
0a31bc97 | 2954 | */ |
118f2875 | 2955 | folio->memcg_data = (unsigned long)memcg; |
7a81b88c | 2956 | } |
66e1707b | 2957 | |
4b569387 NP |
2958 | /** |
2959 | * mem_cgroup_commit_charge - commit a previously successful try_charge(). | |
2960 | * @folio: folio to commit the charge to. | |
2961 | * @memcg: memcg previously charged. | |
2962 | */ | |
2963 | void mem_cgroup_commit_charge(struct folio *folio, struct mem_cgroup *memcg) | |
2964 | { | |
2965 | css_get(&memcg->css); | |
2966 | commit_charge(folio, memcg); | |
2967 | ||
2968 | local_irq_disable(); | |
2969 | mem_cgroup_charge_statistics(memcg, folio_nr_pages(folio)); | |
2970 | memcg_check_events(memcg, folio_nid(folio)); | |
2971 | local_irq_enable(); | |
2972 | } | |
2973 | ||
84c07d11 | 2974 | #ifdef CONFIG_MEMCG_KMEM |
41eb5df1 WL |
2975 | /* |
2976 | * The allocated objcg pointers array is not accounted directly. | |
2977 | * Moreover, it should not come from DMA buffer and is not readily | |
2978 | * reclaimable. So those GFP bits should be masked off. | |
2979 | */ | |
24948e3b RG |
2980 | #define OBJCGS_CLEAR_MASK (__GFP_DMA | __GFP_RECLAIMABLE | \ |
2981 | __GFP_ACCOUNT | __GFP_NOFAIL) | |
41eb5df1 | 2982 | |
a7ebf564 WL |
2983 | /* |
2984 | * mod_objcg_mlstate() may be called with irq enabled, so | |
2985 | * mod_memcg_lruvec_state() should be used. | |
2986 | */ | |
2987 | static inline void mod_objcg_mlstate(struct obj_cgroup *objcg, | |
2988 | struct pglist_data *pgdat, | |
2989 | enum node_stat_item idx, int nr) | |
2990 | { | |
2991 | struct mem_cgroup *memcg; | |
2992 | struct lruvec *lruvec; | |
2993 | ||
2994 | rcu_read_lock(); | |
2995 | memcg = obj_cgroup_memcg(objcg); | |
2996 | lruvec = mem_cgroup_lruvec(memcg, pgdat); | |
2997 | mod_memcg_lruvec_state(lruvec, idx, nr); | |
2998 | rcu_read_unlock(); | |
2999 | } | |
3000 | ||
4b5f8d9a VB |
3001 | int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, |
3002 | gfp_t gfp, bool new_slab) | |
10befea9 | 3003 | { |
4b5f8d9a | 3004 | unsigned int objects = objs_per_slab(s, slab); |
2e9bd483 | 3005 | unsigned long memcg_data; |
10befea9 RG |
3006 | void *vec; |
3007 | ||
41eb5df1 | 3008 | gfp &= ~OBJCGS_CLEAR_MASK; |
10befea9 | 3009 | vec = kcalloc_node(objects, sizeof(struct obj_cgroup *), gfp, |
4b5f8d9a | 3010 | slab_nid(slab)); |
10befea9 RG |
3011 | if (!vec) |
3012 | return -ENOMEM; | |
3013 | ||
2e9bd483 | 3014 | memcg_data = (unsigned long) vec | MEMCG_DATA_OBJCGS; |
4b5f8d9a | 3015 | if (new_slab) { |
2e9bd483 | 3016 | /* |
4b5f8d9a VB |
3017 | * If the slab is brand new and nobody can yet access its |
3018 | * memcg_data, no synchronization is required and memcg_data can | |
3019 | * be simply assigned. | |
2e9bd483 | 3020 | */ |
4b5f8d9a VB |
3021 | slab->memcg_data = memcg_data; |
3022 | } else if (cmpxchg(&slab->memcg_data, 0, memcg_data)) { | |
2e9bd483 | 3023 | /* |
4b5f8d9a VB |
3024 | * If the slab is already in use, somebody can allocate and |
3025 | * assign obj_cgroups in parallel. In this case the existing | |
2e9bd483 RG |
3026 | * objcg vector should be reused. |
3027 | */ | |
10befea9 | 3028 | kfree(vec); |
2e9bd483 RG |
3029 | return 0; |
3030 | } | |
10befea9 | 3031 | |
2e9bd483 | 3032 | kmemleak_not_leak(vec); |
10befea9 RG |
3033 | return 0; |
3034 | } | |
3035 | ||
fc4db90f RG |
3036 | static __always_inline |
3037 | struct mem_cgroup *mem_cgroup_from_obj_folio(struct folio *folio, void *p) | |
8380ce47 | 3038 | { |
8380ce47 | 3039 | /* |
9855609b RG |
3040 | * Slab objects are accounted individually, not per-page. |
3041 | * Memcg membership data for each individual object is saved in | |
4b5f8d9a | 3042 | * slab->memcg_data. |
8380ce47 | 3043 | */ |
4b5f8d9a VB |
3044 | if (folio_test_slab(folio)) { |
3045 | struct obj_cgroup **objcgs; | |
3046 | struct slab *slab; | |
9855609b RG |
3047 | unsigned int off; |
3048 | ||
4b5f8d9a VB |
3049 | slab = folio_slab(folio); |
3050 | objcgs = slab_objcgs(slab); | |
3051 | if (!objcgs) | |
3052 | return NULL; | |
3053 | ||
3054 | off = obj_to_index(slab->slab_cache, slab, p); | |
3055 | if (objcgs[off]) | |
3056 | return obj_cgroup_memcg(objcgs[off]); | |
10befea9 RG |
3057 | |
3058 | return NULL; | |
9855609b | 3059 | } |
8380ce47 | 3060 | |
bcfe06bf | 3061 | /* |
becacb04 | 3062 | * folio_memcg_check() is used here, because in theory we can encounter |
4b5f8d9a VB |
3063 | * a folio where the slab flag has been cleared already, but |
3064 | * slab->memcg_data has not been freed yet | |
becacb04 | 3065 | * folio_memcg_check() will guarantee that a proper memory |
bcfe06bf RG |
3066 | * cgroup pointer or NULL will be returned. |
3067 | */ | |
becacb04 | 3068 | return folio_memcg_check(folio); |
8380ce47 RG |
3069 | } |
3070 | ||
fc4db90f RG |
3071 | /* |
3072 | * Returns a pointer to the memory cgroup to which the kernel object is charged. | |
3073 | * | |
3074 | * A passed kernel object can be a slab object, vmalloc object or a generic | |
3075 | * kernel page, so different mechanisms for getting the memory cgroup pointer | |
3076 | * should be used. | |
3077 | * | |
3078 | * In certain cases (e.g. kernel stacks or large kmallocs with SLUB) the caller | |
3079 | * can not know for sure how the kernel object is implemented. | |
3080 | * mem_cgroup_from_obj() can be safely used in such cases. | |
3081 | * | |
3082 | * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(), | |
3083 | * cgroup_mutex, etc. | |
3084 | */ | |
3085 | struct mem_cgroup *mem_cgroup_from_obj(void *p) | |
3086 | { | |
3087 | struct folio *folio; | |
3088 | ||
3089 | if (mem_cgroup_disabled()) | |
3090 | return NULL; | |
3091 | ||
3092 | if (unlikely(is_vmalloc_addr(p))) | |
3093 | folio = page_folio(vmalloc_to_page(p)); | |
3094 | else | |
3095 | folio = virt_to_folio(p); | |
3096 | ||
3097 | return mem_cgroup_from_obj_folio(folio, p); | |
3098 | } | |
3099 | ||
3100 | /* | |
3101 | * Returns a pointer to the memory cgroup to which the kernel object is charged. | |
3102 | * Similar to mem_cgroup_from_obj(), but faster and not suitable for objects, | |
3103 | * allocated using vmalloc(). | |
3104 | * | |
3105 | * A passed kernel object must be a slab object or a generic kernel page. | |
3106 | * | |
3107 | * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(), | |
3108 | * cgroup_mutex, etc. | |
3109 | */ | |
3110 | struct mem_cgroup *mem_cgroup_from_slab_obj(void *p) | |
3111 | { | |
3112 | if (mem_cgroup_disabled()) | |
3113 | return NULL; | |
3114 | ||
3115 | return mem_cgroup_from_obj_folio(virt_to_folio(p), p); | |
3116 | } | |
3117 | ||
f4840ccf JW |
3118 | static struct obj_cgroup *__get_obj_cgroup_from_memcg(struct mem_cgroup *memcg) |
3119 | { | |
3120 | struct obj_cgroup *objcg = NULL; | |
3121 | ||
7848ed62 | 3122 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) { |
f4840ccf | 3123 | objcg = rcu_dereference(memcg->objcg); |
7d0715d0 | 3124 | if (likely(objcg && obj_cgroup_tryget(objcg))) |
f4840ccf JW |
3125 | break; |
3126 | objcg = NULL; | |
3127 | } | |
3128 | return objcg; | |
3129 | } | |
3130 | ||
1aacbd35 RG |
3131 | static struct obj_cgroup *current_objcg_update(void) |
3132 | { | |
3133 | struct mem_cgroup *memcg; | |
3134 | struct obj_cgroup *old, *objcg = NULL; | |
3135 | ||
3136 | do { | |
3137 | /* Atomically drop the update bit. */ | |
3138 | old = xchg(¤t->objcg, NULL); | |
3139 | if (old) { | |
3140 | old = (struct obj_cgroup *) | |
3141 | ((unsigned long)old & ~CURRENT_OBJCG_UPDATE_FLAG); | |
3142 | if (old) | |
3143 | obj_cgroup_put(old); | |
3144 | ||
3145 | old = NULL; | |
3146 | } | |
3147 | ||
3148 | /* If new objcg is NULL, no reason for the second atomic update. */ | |
3149 | if (!current->mm || (current->flags & PF_KTHREAD)) | |
3150 | return NULL; | |
3151 | ||
3152 | /* | |
3153 | * Release the objcg pointer from the previous iteration, | |
3154 | * if try_cmpxcg() below fails. | |
3155 | */ | |
3156 | if (unlikely(objcg)) { | |
3157 | obj_cgroup_put(objcg); | |
3158 | objcg = NULL; | |
3159 | } | |
3160 | ||
3161 | /* | |
3162 | * Obtain the new objcg pointer. The current task can be | |
3163 | * asynchronously moved to another memcg and the previous | |
3164 | * memcg can be offlined. So let's get the memcg pointer | |
3165 | * and try get a reference to objcg under a rcu read lock. | |
3166 | */ | |
3167 | ||
3168 | rcu_read_lock(); | |
3169 | memcg = mem_cgroup_from_task(current); | |
3170 | objcg = __get_obj_cgroup_from_memcg(memcg); | |
3171 | rcu_read_unlock(); | |
3172 | ||
3173 | /* | |
3174 | * Try set up a new objcg pointer atomically. If it | |
3175 | * fails, it means the update flag was set concurrently, so | |
3176 | * the whole procedure should be repeated. | |
3177 | */ | |
3178 | } while (!try_cmpxchg(¤t->objcg, &old, objcg)); | |
3179 | ||
3180 | return objcg; | |
3181 | } | |
3182 | ||
e86828e5 RG |
3183 | __always_inline struct obj_cgroup *current_obj_cgroup(void) |
3184 | { | |
3185 | struct mem_cgroup *memcg; | |
3186 | struct obj_cgroup *objcg; | |
3187 | ||
3188 | if (in_task()) { | |
3189 | memcg = current->active_memcg; | |
3190 | if (unlikely(memcg)) | |
3191 | goto from_memcg; | |
3192 | ||
3193 | objcg = READ_ONCE(current->objcg); | |
3194 | if (unlikely((unsigned long)objcg & CURRENT_OBJCG_UPDATE_FLAG)) | |
3195 | objcg = current_objcg_update(); | |
3196 | /* | |
3197 | * Objcg reference is kept by the task, so it's safe | |
3198 | * to use the objcg by the current task. | |
3199 | */ | |
3200 | return objcg; | |
3201 | } | |
3202 | ||
3203 | memcg = this_cpu_read(int_active_memcg); | |
3204 | if (unlikely(memcg)) | |
3205 | goto from_memcg; | |
3206 | ||
3207 | return NULL; | |
3208 | ||
3209 | from_memcg: | |
5f79489a | 3210 | objcg = NULL; |
e86828e5 RG |
3211 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) { |
3212 | /* | |
3213 | * Memcg pointer is protected by scope (see set_active_memcg()) | |
3214 | * and is pinning the corresponding objcg, so objcg can't go | |
3215 | * away and can be used within the scope without any additional | |
3216 | * protection. | |
3217 | */ | |
3218 | objcg = rcu_dereference_check(memcg->objcg, 1); | |
3219 | if (likely(objcg)) | |
3220 | break; | |
e86828e5 RG |
3221 | } |
3222 | ||
3223 | return objcg; | |
3224 | } | |
3225 | ||
074e3e26 | 3226 | struct obj_cgroup *get_obj_cgroup_from_folio(struct folio *folio) |
f4840ccf JW |
3227 | { |
3228 | struct obj_cgroup *objcg; | |
3229 | ||
f7a449f7 | 3230 | if (!memcg_kmem_online()) |
f4840ccf JW |
3231 | return NULL; |
3232 | ||
074e3e26 MWO |
3233 | if (folio_memcg_kmem(folio)) { |
3234 | objcg = __folio_objcg(folio); | |
f4840ccf JW |
3235 | obj_cgroup_get(objcg); |
3236 | } else { | |
3237 | struct mem_cgroup *memcg; | |
bf4f0599 | 3238 | |
f4840ccf | 3239 | rcu_read_lock(); |
074e3e26 | 3240 | memcg = __folio_memcg(folio); |
f4840ccf JW |
3241 | if (memcg) |
3242 | objcg = __get_obj_cgroup_from_memcg(memcg); | |
3243 | else | |
3244 | objcg = NULL; | |
3245 | rcu_read_unlock(); | |
3246 | } | |
bf4f0599 RG |
3247 | return objcg; |
3248 | } | |
3249 | ||
a8c49af3 YA |
3250 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) |
3251 | { | |
3252 | mod_memcg_state(memcg, MEMCG_KMEM, nr_pages); | |
3253 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { | |
3254 | if (nr_pages > 0) | |
3255 | page_counter_charge(&memcg->kmem, nr_pages); | |
3256 | else | |
3257 | page_counter_uncharge(&memcg->kmem, -nr_pages); | |
3258 | } | |
3259 | } | |
3260 | ||
3261 | ||
f1286fae MS |
3262 | /* |
3263 | * obj_cgroup_uncharge_pages: uncharge a number of kernel pages from a objcg | |
3264 | * @objcg: object cgroup to uncharge | |
3265 | * @nr_pages: number of pages to uncharge | |
3266 | */ | |
e74d2259 MS |
3267 | static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, |
3268 | unsigned int nr_pages) | |
3269 | { | |
3270 | struct mem_cgroup *memcg; | |
3271 | ||
3272 | memcg = get_mem_cgroup_from_objcg(objcg); | |
e74d2259 | 3273 | |
a8c49af3 | 3274 | memcg_account_kmem(memcg, -nr_pages); |
f1286fae | 3275 | refill_stock(memcg, nr_pages); |
e74d2259 | 3276 | |
e74d2259 | 3277 | css_put(&memcg->css); |
e74d2259 MS |
3278 | } |
3279 | ||
f1286fae MS |
3280 | /* |
3281 | * obj_cgroup_charge_pages: charge a number of kernel pages to a objcg | |
3282 | * @objcg: object cgroup to charge | |
45264778 | 3283 | * @gfp: reclaim mode |
92d0510c | 3284 | * @nr_pages: number of pages to charge |
45264778 VD |
3285 | * |
3286 | * Returns 0 on success, an error code on failure. | |
3287 | */ | |
f1286fae MS |
3288 | static int obj_cgroup_charge_pages(struct obj_cgroup *objcg, gfp_t gfp, |
3289 | unsigned int nr_pages) | |
7ae1e1d0 | 3290 | { |
f1286fae | 3291 | struct mem_cgroup *memcg; |
7ae1e1d0 GC |
3292 | int ret; |
3293 | ||
f1286fae MS |
3294 | memcg = get_mem_cgroup_from_objcg(objcg); |
3295 | ||
c5c8b16b | 3296 | ret = try_charge_memcg(memcg, gfp, nr_pages); |
52c29b04 | 3297 | if (ret) |
f1286fae | 3298 | goto out; |
52c29b04 | 3299 | |
a8c49af3 | 3300 | memcg_account_kmem(memcg, nr_pages); |
f1286fae MS |
3301 | out: |
3302 | css_put(&memcg->css); | |
4b13f64d | 3303 | |
f1286fae | 3304 | return ret; |
4b13f64d RG |
3305 | } |
3306 | ||
45264778 | 3307 | /** |
f4b00eab | 3308 | * __memcg_kmem_charge_page: charge a kmem page to the current memory cgroup |
45264778 VD |
3309 | * @page: page to charge |
3310 | * @gfp: reclaim mode | |
3311 | * @order: allocation order | |
3312 | * | |
3313 | * Returns 0 on success, an error code on failure. | |
3314 | */ | |
f4b00eab | 3315 | int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) |
7ae1e1d0 | 3316 | { |
b4e0b68f | 3317 | struct obj_cgroup *objcg; |
fcff7d7e | 3318 | int ret = 0; |
7ae1e1d0 | 3319 | |
e86828e5 | 3320 | objcg = current_obj_cgroup(); |
b4e0b68f MS |
3321 | if (objcg) { |
3322 | ret = obj_cgroup_charge_pages(objcg, gfp, 1 << order); | |
4d96ba35 | 3323 | if (!ret) { |
e86828e5 | 3324 | obj_cgroup_get(objcg); |
b4e0b68f | 3325 | page->memcg_data = (unsigned long)objcg | |
18b2db3b | 3326 | MEMCG_DATA_KMEM; |
1a3e1f40 | 3327 | return 0; |
4d96ba35 | 3328 | } |
c4159a75 | 3329 | } |
d05e83a6 | 3330 | return ret; |
7ae1e1d0 | 3331 | } |
49a18eae | 3332 | |
45264778 | 3333 | /** |
f4b00eab | 3334 | * __memcg_kmem_uncharge_page: uncharge a kmem page |
45264778 VD |
3335 | * @page: page to uncharge |
3336 | * @order: allocation order | |
3337 | */ | |
f4b00eab | 3338 | void __memcg_kmem_uncharge_page(struct page *page, int order) |
7ae1e1d0 | 3339 | { |
1b7e4464 | 3340 | struct folio *folio = page_folio(page); |
b4e0b68f | 3341 | struct obj_cgroup *objcg; |
f3ccb2c4 | 3342 | unsigned int nr_pages = 1 << order; |
7ae1e1d0 | 3343 | |
1b7e4464 | 3344 | if (!folio_memcg_kmem(folio)) |
7ae1e1d0 GC |
3345 | return; |
3346 | ||
1b7e4464 | 3347 | objcg = __folio_objcg(folio); |
b4e0b68f | 3348 | obj_cgroup_uncharge_pages(objcg, nr_pages); |
1b7e4464 | 3349 | folio->memcg_data = 0; |
b4e0b68f | 3350 | obj_cgroup_put(objcg); |
60d3fd32 | 3351 | } |
bf4f0599 | 3352 | |
68ac5b3c WL |
3353 | void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, |
3354 | enum node_stat_item idx, int nr) | |
3355 | { | |
fead2b86 | 3356 | struct memcg_stock_pcp *stock; |
56751146 | 3357 | struct obj_cgroup *old = NULL; |
68ac5b3c WL |
3358 | unsigned long flags; |
3359 | int *bytes; | |
3360 | ||
56751146 | 3361 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3362 | stock = this_cpu_ptr(&memcg_stock); |
3363 | ||
68ac5b3c WL |
3364 | /* |
3365 | * Save vmstat data in stock and skip vmstat array update unless | |
3366 | * accumulating over a page of vmstat data or when pgdat or idx | |
3367 | * changes. | |
3368 | */ | |
3b8abb32 | 3369 | if (READ_ONCE(stock->cached_objcg) != objcg) { |
56751146 | 3370 | old = drain_obj_stock(stock); |
68ac5b3c WL |
3371 | obj_cgroup_get(objcg); |
3372 | stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) | |
3373 | ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; | |
3b8abb32 | 3374 | WRITE_ONCE(stock->cached_objcg, objcg); |
68ac5b3c WL |
3375 | stock->cached_pgdat = pgdat; |
3376 | } else if (stock->cached_pgdat != pgdat) { | |
3377 | /* Flush the existing cached vmstat data */ | |
7fa0dacb WL |
3378 | struct pglist_data *oldpg = stock->cached_pgdat; |
3379 | ||
68ac5b3c | 3380 | if (stock->nr_slab_reclaimable_b) { |
7fa0dacb | 3381 | mod_objcg_mlstate(objcg, oldpg, NR_SLAB_RECLAIMABLE_B, |
68ac5b3c WL |
3382 | stock->nr_slab_reclaimable_b); |
3383 | stock->nr_slab_reclaimable_b = 0; | |
3384 | } | |
3385 | if (stock->nr_slab_unreclaimable_b) { | |
7fa0dacb | 3386 | mod_objcg_mlstate(objcg, oldpg, NR_SLAB_UNRECLAIMABLE_B, |
68ac5b3c WL |
3387 | stock->nr_slab_unreclaimable_b); |
3388 | stock->nr_slab_unreclaimable_b = 0; | |
3389 | } | |
3390 | stock->cached_pgdat = pgdat; | |
3391 | } | |
3392 | ||
3393 | bytes = (idx == NR_SLAB_RECLAIMABLE_B) ? &stock->nr_slab_reclaimable_b | |
3394 | : &stock->nr_slab_unreclaimable_b; | |
3395 | /* | |
3396 | * Even for large object >= PAGE_SIZE, the vmstat data will still be | |
3397 | * cached locally at least once before pushing it out. | |
3398 | */ | |
3399 | if (!*bytes) { | |
3400 | *bytes = nr; | |
3401 | nr = 0; | |
3402 | } else { | |
3403 | *bytes += nr; | |
3404 | if (abs(*bytes) > PAGE_SIZE) { | |
3405 | nr = *bytes; | |
3406 | *bytes = 0; | |
3407 | } else { | |
3408 | nr = 0; | |
3409 | } | |
3410 | } | |
3411 | if (nr) | |
3412 | mod_objcg_mlstate(objcg, pgdat, idx, nr); | |
3413 | ||
56751146 SAS |
3414 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
3415 | if (old) | |
3416 | obj_cgroup_put(old); | |
68ac5b3c WL |
3417 | } |
3418 | ||
bf4f0599 RG |
3419 | static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes) |
3420 | { | |
fead2b86 | 3421 | struct memcg_stock_pcp *stock; |
bf4f0599 RG |
3422 | unsigned long flags; |
3423 | bool ret = false; | |
3424 | ||
56751146 | 3425 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3426 | |
3427 | stock = this_cpu_ptr(&memcg_stock); | |
3b8abb32 | 3428 | if (objcg == READ_ONCE(stock->cached_objcg) && stock->nr_bytes >= nr_bytes) { |
bf4f0599 RG |
3429 | stock->nr_bytes -= nr_bytes; |
3430 | ret = true; | |
3431 | } | |
3432 | ||
56751146 | 3433 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
bf4f0599 RG |
3434 | |
3435 | return ret; | |
3436 | } | |
3437 | ||
56751146 | 3438 | static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) |
bf4f0599 | 3439 | { |
3b8abb32 | 3440 | struct obj_cgroup *old = READ_ONCE(stock->cached_objcg); |
bf4f0599 RG |
3441 | |
3442 | if (!old) | |
56751146 | 3443 | return NULL; |
bf4f0599 RG |
3444 | |
3445 | if (stock->nr_bytes) { | |
3446 | unsigned int nr_pages = stock->nr_bytes >> PAGE_SHIFT; | |
3447 | unsigned int nr_bytes = stock->nr_bytes & (PAGE_SIZE - 1); | |
3448 | ||
af9a3b69 JW |
3449 | if (nr_pages) { |
3450 | struct mem_cgroup *memcg; | |
3451 | ||
3452 | memcg = get_mem_cgroup_from_objcg(old); | |
3453 | ||
3454 | memcg_account_kmem(memcg, -nr_pages); | |
3455 | __refill_stock(memcg, nr_pages); | |
3456 | ||
3457 | css_put(&memcg->css); | |
3458 | } | |
bf4f0599 RG |
3459 | |
3460 | /* | |
3461 | * The leftover is flushed to the centralized per-memcg value. | |
3462 | * On the next attempt to refill obj stock it will be moved | |
3463 | * to a per-cpu stock (probably, on an other CPU), see | |
3464 | * refill_obj_stock(). | |
3465 | * | |
3466 | * How often it's flushed is a trade-off between the memory | |
3467 | * limit enforcement accuracy and potential CPU contention, | |
3468 | * so it might be changed in the future. | |
3469 | */ | |
3470 | atomic_add(nr_bytes, &old->nr_charged_bytes); | |
3471 | stock->nr_bytes = 0; | |
3472 | } | |
3473 | ||
68ac5b3c WL |
3474 | /* |
3475 | * Flush the vmstat data in current stock | |
3476 | */ | |
3477 | if (stock->nr_slab_reclaimable_b || stock->nr_slab_unreclaimable_b) { | |
3478 | if (stock->nr_slab_reclaimable_b) { | |
3479 | mod_objcg_mlstate(old, stock->cached_pgdat, | |
3480 | NR_SLAB_RECLAIMABLE_B, | |
3481 | stock->nr_slab_reclaimable_b); | |
3482 | stock->nr_slab_reclaimable_b = 0; | |
3483 | } | |
3484 | if (stock->nr_slab_unreclaimable_b) { | |
3485 | mod_objcg_mlstate(old, stock->cached_pgdat, | |
3486 | NR_SLAB_UNRECLAIMABLE_B, | |
3487 | stock->nr_slab_unreclaimable_b); | |
3488 | stock->nr_slab_unreclaimable_b = 0; | |
3489 | } | |
3490 | stock->cached_pgdat = NULL; | |
3491 | } | |
3492 | ||
3b8abb32 | 3493 | WRITE_ONCE(stock->cached_objcg, NULL); |
56751146 SAS |
3494 | /* |
3495 | * The `old' objects needs to be released by the caller via | |
3496 | * obj_cgroup_put() outside of memcg_stock_pcp::stock_lock. | |
3497 | */ | |
3498 | return old; | |
bf4f0599 RG |
3499 | } |
3500 | ||
3501 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, | |
3502 | struct mem_cgroup *root_memcg) | |
3503 | { | |
3b8abb32 | 3504 | struct obj_cgroup *objcg = READ_ONCE(stock->cached_objcg); |
bf4f0599 RG |
3505 | struct mem_cgroup *memcg; |
3506 | ||
3b8abb32 RG |
3507 | if (objcg) { |
3508 | memcg = obj_cgroup_memcg(objcg); | |
bf4f0599 RG |
3509 | if (memcg && mem_cgroup_is_descendant(memcg, root_memcg)) |
3510 | return true; | |
3511 | } | |
3512 | ||
3513 | return false; | |
3514 | } | |
3515 | ||
5387c904 WL |
3516 | static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes, |
3517 | bool allow_uncharge) | |
bf4f0599 | 3518 | { |
fead2b86 | 3519 | struct memcg_stock_pcp *stock; |
56751146 | 3520 | struct obj_cgroup *old = NULL; |
bf4f0599 | 3521 | unsigned long flags; |
5387c904 | 3522 | unsigned int nr_pages = 0; |
bf4f0599 | 3523 | |
56751146 | 3524 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3525 | |
3526 | stock = this_cpu_ptr(&memcg_stock); | |
3b8abb32 | 3527 | if (READ_ONCE(stock->cached_objcg) != objcg) { /* reset if necessary */ |
56751146 | 3528 | old = drain_obj_stock(stock); |
bf4f0599 | 3529 | obj_cgroup_get(objcg); |
3b8abb32 | 3530 | WRITE_ONCE(stock->cached_objcg, objcg); |
5387c904 WL |
3531 | stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) |
3532 | ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; | |
3533 | allow_uncharge = true; /* Allow uncharge when objcg changes */ | |
bf4f0599 RG |
3534 | } |
3535 | stock->nr_bytes += nr_bytes; | |
3536 | ||
5387c904 WL |
3537 | if (allow_uncharge && (stock->nr_bytes > PAGE_SIZE)) { |
3538 | nr_pages = stock->nr_bytes >> PAGE_SHIFT; | |
3539 | stock->nr_bytes &= (PAGE_SIZE - 1); | |
3540 | } | |
bf4f0599 | 3541 | |
56751146 SAS |
3542 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
3543 | if (old) | |
3544 | obj_cgroup_put(old); | |
5387c904 WL |
3545 | |
3546 | if (nr_pages) | |
3547 | obj_cgroup_uncharge_pages(objcg, nr_pages); | |
bf4f0599 RG |
3548 | } |
3549 | ||
3550 | int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size) | |
3551 | { | |
bf4f0599 RG |
3552 | unsigned int nr_pages, nr_bytes; |
3553 | int ret; | |
3554 | ||
3555 | if (consume_obj_stock(objcg, size)) | |
3556 | return 0; | |
3557 | ||
3558 | /* | |
5387c904 | 3559 | * In theory, objcg->nr_charged_bytes can have enough |
bf4f0599 | 3560 | * pre-charged bytes to satisfy the allocation. However, |
5387c904 WL |
3561 | * flushing objcg->nr_charged_bytes requires two atomic |
3562 | * operations, and objcg->nr_charged_bytes can't be big. | |
3563 | * The shared objcg->nr_charged_bytes can also become a | |
3564 | * performance bottleneck if all tasks of the same memcg are | |
3565 | * trying to update it. So it's better to ignore it and try | |
3566 | * grab some new pages. The stock's nr_bytes will be flushed to | |
3567 | * objcg->nr_charged_bytes later on when objcg changes. | |
3568 | * | |
3569 | * The stock's nr_bytes may contain enough pre-charged bytes | |
3570 | * to allow one less page from being charged, but we can't rely | |
3571 | * on the pre-charged bytes not being changed outside of | |
3572 | * consume_obj_stock() or refill_obj_stock(). So ignore those | |
3573 | * pre-charged bytes as well when charging pages. To avoid a | |
3574 | * page uncharge right after a page charge, we set the | |
3575 | * allow_uncharge flag to false when calling refill_obj_stock() | |
3576 | * to temporarily allow the pre-charged bytes to exceed the page | |
3577 | * size limit. The maximum reachable value of the pre-charged | |
3578 | * bytes is (sizeof(object) + PAGE_SIZE - 2) if there is no data | |
3579 | * race. | |
bf4f0599 | 3580 | */ |
bf4f0599 RG |
3581 | nr_pages = size >> PAGE_SHIFT; |
3582 | nr_bytes = size & (PAGE_SIZE - 1); | |
3583 | ||
3584 | if (nr_bytes) | |
3585 | nr_pages += 1; | |
3586 | ||
e74d2259 | 3587 | ret = obj_cgroup_charge_pages(objcg, gfp, nr_pages); |
bf4f0599 | 3588 | if (!ret && nr_bytes) |
5387c904 | 3589 | refill_obj_stock(objcg, PAGE_SIZE - nr_bytes, false); |
bf4f0599 | 3590 | |
bf4f0599 RG |
3591 | return ret; |
3592 | } | |
3593 | ||
3594 | void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size) | |
3595 | { | |
5387c904 | 3596 | refill_obj_stock(objcg, size, true); |
bf4f0599 RG |
3597 | } |
3598 | ||
84c07d11 | 3599 | #endif /* CONFIG_MEMCG_KMEM */ |
7ae1e1d0 | 3600 | |
ca3e0214 | 3601 | /* |
be6c8982 | 3602 | * Because page_memcg(head) is not set on tails, set it now. |
ca3e0214 | 3603 | */ |
be6c8982 | 3604 | void split_page_memcg(struct page *head, unsigned int nr) |
ca3e0214 | 3605 | { |
1b7e4464 MWO |
3606 | struct folio *folio = page_folio(head); |
3607 | struct mem_cgroup *memcg = folio_memcg(folio); | |
e94c8a9c | 3608 | int i; |
ca3e0214 | 3609 | |
be6c8982 | 3610 | if (mem_cgroup_disabled() || !memcg) |
3d37c4a9 | 3611 | return; |
b070e65c | 3612 | |
be6c8982 | 3613 | for (i = 1; i < nr; i++) |
1b7e4464 | 3614 | folio_page(folio, i)->memcg_data = folio->memcg_data; |
b4e0b68f | 3615 | |
1b7e4464 MWO |
3616 | if (folio_memcg_kmem(folio)) |
3617 | obj_cgroup_get_many(__folio_objcg(folio), nr - 1); | |
b4e0b68f MS |
3618 | else |
3619 | css_get_many(&memcg->css, nr - 1); | |
ca3e0214 | 3620 | } |
ca3e0214 | 3621 | |
e55b9f96 | 3622 | #ifdef CONFIG_SWAP |
02491447 DN |
3623 | /** |
3624 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
3625 | * @entry: swap entry to be moved | |
3626 | * @from: mem_cgroup which the entry is moved from | |
3627 | * @to: mem_cgroup which the entry is moved to | |
3628 | * | |
3629 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
3630 | * as the mem_cgroup's id of @from. | |
3631 | * | |
3632 | * Returns 0 on success, -EINVAL on failure. | |
3633 | * | |
3e32cb2e | 3634 | * The caller must have charged to @to, IOW, called page_counter_charge() about |
02491447 DN |
3635 | * both res and memsw, and called css_get(). |
3636 | */ | |
3637 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 3638 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
3639 | { |
3640 | unsigned short old_id, new_id; | |
3641 | ||
34c00c31 LZ |
3642 | old_id = mem_cgroup_id(from); |
3643 | new_id = mem_cgroup_id(to); | |
02491447 DN |
3644 | |
3645 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
c9019e9b JW |
3646 | mod_memcg_state(from, MEMCG_SWAP, -1); |
3647 | mod_memcg_state(to, MEMCG_SWAP, 1); | |
02491447 DN |
3648 | return 0; |
3649 | } | |
3650 | return -EINVAL; | |
3651 | } | |
3652 | #else | |
3653 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 3654 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
3655 | { |
3656 | return -EINVAL; | |
3657 | } | |
8c7c6e34 | 3658 | #endif |
d13d1443 | 3659 | |
bbec2e15 | 3660 | static DEFINE_MUTEX(memcg_max_mutex); |
f212ad7c | 3661 | |
bbec2e15 RG |
3662 | static int mem_cgroup_resize_max(struct mem_cgroup *memcg, |
3663 | unsigned long max, bool memsw) | |
628f4235 | 3664 | { |
3e32cb2e | 3665 | bool enlarge = false; |
bb4a7ea2 | 3666 | bool drained = false; |
3e32cb2e | 3667 | int ret; |
c054a78c YZ |
3668 | bool limits_invariant; |
3669 | struct page_counter *counter = memsw ? &memcg->memsw : &memcg->memory; | |
81d39c20 | 3670 | |
3e32cb2e | 3671 | do { |
628f4235 KH |
3672 | if (signal_pending(current)) { |
3673 | ret = -EINTR; | |
3674 | break; | |
3675 | } | |
3e32cb2e | 3676 | |
bbec2e15 | 3677 | mutex_lock(&memcg_max_mutex); |
c054a78c YZ |
3678 | /* |
3679 | * Make sure that the new limit (memsw or memory limit) doesn't | |
bbec2e15 | 3680 | * break our basic invariant rule memory.max <= memsw.max. |
c054a78c | 3681 | */ |
15b42562 | 3682 | limits_invariant = memsw ? max >= READ_ONCE(memcg->memory.max) : |
bbec2e15 | 3683 | max <= memcg->memsw.max; |
c054a78c | 3684 | if (!limits_invariant) { |
bbec2e15 | 3685 | mutex_unlock(&memcg_max_mutex); |
8c7c6e34 | 3686 | ret = -EINVAL; |
8c7c6e34 KH |
3687 | break; |
3688 | } | |
bbec2e15 | 3689 | if (max > counter->max) |
3e32cb2e | 3690 | enlarge = true; |
bbec2e15 RG |
3691 | ret = page_counter_set_max(counter, max); |
3692 | mutex_unlock(&memcg_max_mutex); | |
8c7c6e34 KH |
3693 | |
3694 | if (!ret) | |
3695 | break; | |
3696 | ||
bb4a7ea2 SB |
3697 | if (!drained) { |
3698 | drain_all_stock(memcg); | |
3699 | drained = true; | |
3700 | continue; | |
3701 | } | |
3702 | ||
73b73bac | 3703 | if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, |
55ab834a | 3704 | memsw ? 0 : MEMCG_RECLAIM_MAY_SWAP)) { |
1ab5c056 AR |
3705 | ret = -EBUSY; |
3706 | break; | |
3707 | } | |
3708 | } while (true); | |
3e32cb2e | 3709 | |
3c11ecf4 KH |
3710 | if (!ret && enlarge) |
3711 | memcg_oom_recover(memcg); | |
3e32cb2e | 3712 | |
628f4235 KH |
3713 | return ret; |
3714 | } | |
3715 | ||
ef8f2327 | 3716 | unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, |
0608f43d AM |
3717 | gfp_t gfp_mask, |
3718 | unsigned long *total_scanned) | |
3719 | { | |
3720 | unsigned long nr_reclaimed = 0; | |
ef8f2327 | 3721 | struct mem_cgroup_per_node *mz, *next_mz = NULL; |
0608f43d AM |
3722 | unsigned long reclaimed; |
3723 | int loop = 0; | |
ef8f2327 | 3724 | struct mem_cgroup_tree_per_node *mctz; |
3e32cb2e | 3725 | unsigned long excess; |
0608f43d | 3726 | |
e4dde56c YZ |
3727 | if (lru_gen_enabled()) |
3728 | return 0; | |
3729 | ||
0608f43d AM |
3730 | if (order > 0) |
3731 | return 0; | |
3732 | ||
2ab082ba | 3733 | mctz = soft_limit_tree.rb_tree_per_node[pgdat->node_id]; |
d6507ff5 MH |
3734 | |
3735 | /* | |
3736 | * Do not even bother to check the largest node if the root | |
3737 | * is empty. Do it lockless to prevent lock bouncing. Races | |
3738 | * are acceptable as soft limit is best effort anyway. | |
3739 | */ | |
bfc7228b | 3740 | if (!mctz || RB_EMPTY_ROOT(&mctz->rb_root)) |
d6507ff5 MH |
3741 | return 0; |
3742 | ||
0608f43d AM |
3743 | /* |
3744 | * This loop can run a while, specially if mem_cgroup's continuously | |
3745 | * keep exceeding their soft limit and putting the system under | |
3746 | * pressure | |
3747 | */ | |
3748 | do { | |
3749 | if (next_mz) | |
3750 | mz = next_mz; | |
3751 | else | |
3752 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
3753 | if (!mz) | |
3754 | break; | |
3755 | ||
ef8f2327 | 3756 | reclaimed = mem_cgroup_soft_reclaim(mz->memcg, pgdat, |
d8f65338 | 3757 | gfp_mask, total_scanned); |
0608f43d | 3758 | nr_reclaimed += reclaimed; |
0a31bc97 | 3759 | spin_lock_irq(&mctz->lock); |
0608f43d AM |
3760 | |
3761 | /* | |
3762 | * If we failed to reclaim anything from this memory cgroup | |
3763 | * it is time to move on to the next cgroup | |
3764 | */ | |
3765 | next_mz = NULL; | |
bc2f2e7f VD |
3766 | if (!reclaimed) |
3767 | next_mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
3768 | ||
3e32cb2e | 3769 | excess = soft_limit_excess(mz->memcg); |
0608f43d AM |
3770 | /* |
3771 | * One school of thought says that we should not add | |
3772 | * back the node to the tree if reclaim returns 0. | |
3773 | * But our reclaim could return 0, simply because due | |
3774 | * to priority we are exposing a smaller subset of | |
3775 | * memory to reclaim from. Consider this as a longer | |
3776 | * term TODO. | |
3777 | */ | |
3778 | /* If excess == 0, no tree ops */ | |
cf2c8127 | 3779 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 3780 | spin_unlock_irq(&mctz->lock); |
0608f43d AM |
3781 | css_put(&mz->memcg->css); |
3782 | loop++; | |
3783 | /* | |
3784 | * Could not reclaim anything and there are no more | |
3785 | * mem cgroups to try or we seem to be looping without | |
3786 | * reclaiming anything. | |
3787 | */ | |
3788 | if (!nr_reclaimed && | |
3789 | (next_mz == NULL || | |
3790 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
3791 | break; | |
3792 | } while (!nr_reclaimed); | |
3793 | if (next_mz) | |
3794 | css_put(&next_mz->memcg->css); | |
3795 | return nr_reclaimed; | |
3796 | } | |
3797 | ||
c26251f9 | 3798 | /* |
51038171 | 3799 | * Reclaims as many pages from the given memcg as possible. |
c26251f9 MH |
3800 | * |
3801 | * Caller is responsible for holding css reference for memcg. | |
3802 | */ | |
3803 | static int mem_cgroup_force_empty(struct mem_cgroup *memcg) | |
3804 | { | |
d977aa93 | 3805 | int nr_retries = MAX_RECLAIM_RETRIES; |
c26251f9 | 3806 | |
c1e862c1 KH |
3807 | /* we call try-to-free pages for make this cgroup empty */ |
3808 | lru_add_drain_all(); | |
d12c60f6 JS |
3809 | |
3810 | drain_all_stock(memcg); | |
3811 | ||
f817ed48 | 3812 | /* try to free all pages in this cgroup */ |
3e32cb2e | 3813 | while (nr_retries && page_counter_read(&memcg->memory)) { |
c26251f9 MH |
3814 | if (signal_pending(current)) |
3815 | return -EINTR; | |
3816 | ||
73b73bac | 3817 | if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, |
55ab834a | 3818 | MEMCG_RECLAIM_MAY_SWAP)) |
f817ed48 | 3819 | nr_retries--; |
f817ed48 | 3820 | } |
ab5196c2 MH |
3821 | |
3822 | return 0; | |
cc847582 KH |
3823 | } |
3824 | ||
6770c64e TH |
3825 | static ssize_t mem_cgroup_force_empty_write(struct kernfs_open_file *of, |
3826 | char *buf, size_t nbytes, | |
3827 | loff_t off) | |
c1e862c1 | 3828 | { |
6770c64e | 3829 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
c26251f9 | 3830 | |
d8423011 MH |
3831 | if (mem_cgroup_is_root(memcg)) |
3832 | return -EINVAL; | |
6770c64e | 3833 | return mem_cgroup_force_empty(memcg) ?: nbytes; |
c1e862c1 KH |
3834 | } |
3835 | ||
182446d0 TH |
3836 | static u64 mem_cgroup_hierarchy_read(struct cgroup_subsys_state *css, |
3837 | struct cftype *cft) | |
18f59ea7 | 3838 | { |
bef8620c | 3839 | return 1; |
18f59ea7 BS |
3840 | } |
3841 | ||
182446d0 TH |
3842 | static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css, |
3843 | struct cftype *cft, u64 val) | |
18f59ea7 | 3844 | { |
bef8620c | 3845 | if (val == 1) |
0b8f73e1 | 3846 | return 0; |
567fb435 | 3847 | |
bef8620c RG |
3848 | pr_warn_once("Non-hierarchical mode is deprecated. " |
3849 | "Please report your usecase to linux-mm@kvack.org if you " | |
3850 | "depend on this functionality.\n"); | |
567fb435 | 3851 | |
bef8620c | 3852 | return -EINVAL; |
18f59ea7 BS |
3853 | } |
3854 | ||
6f646156 | 3855 | static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) |
ce00a967 | 3856 | { |
42a30035 | 3857 | unsigned long val; |
ce00a967 | 3858 | |
3e32cb2e | 3859 | if (mem_cgroup_is_root(memcg)) { |
a2174e95 | 3860 | /* |
f82a7a86 YA |
3861 | * Approximate root's usage from global state. This isn't |
3862 | * perfect, but the root usage was always an approximation. | |
a2174e95 | 3863 | */ |
f82a7a86 YA |
3864 | val = global_node_page_state(NR_FILE_PAGES) + |
3865 | global_node_page_state(NR_ANON_MAPPED); | |
42a30035 | 3866 | if (swap) |
f82a7a86 | 3867 | val += total_swap_pages - get_nr_swap_pages(); |
3e32cb2e | 3868 | } else { |
ce00a967 | 3869 | if (!swap) |
3e32cb2e | 3870 | val = page_counter_read(&memcg->memory); |
ce00a967 | 3871 | else |
3e32cb2e | 3872 | val = page_counter_read(&memcg->memsw); |
ce00a967 | 3873 | } |
c12176d3 | 3874 | return val; |
ce00a967 JW |
3875 | } |
3876 | ||
3e32cb2e JW |
3877 | enum { |
3878 | RES_USAGE, | |
3879 | RES_LIMIT, | |
3880 | RES_MAX_USAGE, | |
3881 | RES_FAILCNT, | |
3882 | RES_SOFT_LIMIT, | |
3883 | }; | |
ce00a967 | 3884 | |
791badbd | 3885 | static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css, |
05b84301 | 3886 | struct cftype *cft) |
8cdea7c0 | 3887 | { |
182446d0 | 3888 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3e32cb2e | 3889 | struct page_counter *counter; |
af36f906 | 3890 | |
3e32cb2e | 3891 | switch (MEMFILE_TYPE(cft->private)) { |
8c7c6e34 | 3892 | case _MEM: |
3e32cb2e JW |
3893 | counter = &memcg->memory; |
3894 | break; | |
8c7c6e34 | 3895 | case _MEMSWAP: |
3e32cb2e JW |
3896 | counter = &memcg->memsw; |
3897 | break; | |
510fc4e1 | 3898 | case _KMEM: |
3e32cb2e | 3899 | counter = &memcg->kmem; |
510fc4e1 | 3900 | break; |
d55f90bf | 3901 | case _TCP: |
0db15298 | 3902 | counter = &memcg->tcpmem; |
d55f90bf | 3903 | break; |
8c7c6e34 KH |
3904 | default: |
3905 | BUG(); | |
8c7c6e34 | 3906 | } |
3e32cb2e JW |
3907 | |
3908 | switch (MEMFILE_ATTR(cft->private)) { | |
3909 | case RES_USAGE: | |
3910 | if (counter == &memcg->memory) | |
c12176d3 | 3911 | return (u64)mem_cgroup_usage(memcg, false) * PAGE_SIZE; |
3e32cb2e | 3912 | if (counter == &memcg->memsw) |
c12176d3 | 3913 | return (u64)mem_cgroup_usage(memcg, true) * PAGE_SIZE; |
3e32cb2e JW |
3914 | return (u64)page_counter_read(counter) * PAGE_SIZE; |
3915 | case RES_LIMIT: | |
bbec2e15 | 3916 | return (u64)counter->max * PAGE_SIZE; |
3e32cb2e JW |
3917 | case RES_MAX_USAGE: |
3918 | return (u64)counter->watermark * PAGE_SIZE; | |
3919 | case RES_FAILCNT: | |
3920 | return counter->failcnt; | |
3921 | case RES_SOFT_LIMIT: | |
2178e20c | 3922 | return (u64)READ_ONCE(memcg->soft_limit) * PAGE_SIZE; |
3e32cb2e JW |
3923 | default: |
3924 | BUG(); | |
3925 | } | |
8cdea7c0 | 3926 | } |
510fc4e1 | 3927 | |
6b0ba2ab FS |
3928 | /* |
3929 | * This function doesn't do anything useful. Its only job is to provide a read | |
3930 | * handler for a file so that cgroup_file_mode() will add read permissions. | |
3931 | */ | |
3932 | static int mem_cgroup_dummy_seq_show(__always_unused struct seq_file *m, | |
3933 | __always_unused void *v) | |
3934 | { | |
3935 | return -EINVAL; | |
3936 | } | |
3937 | ||
84c07d11 | 3938 | #ifdef CONFIG_MEMCG_KMEM |
567e9ab2 | 3939 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
d6441637 | 3940 | { |
bf4f0599 | 3941 | struct obj_cgroup *objcg; |
d6441637 | 3942 | |
9c94bef9 | 3943 | if (mem_cgroup_kmem_disabled()) |
b313aeee VD |
3944 | return 0; |
3945 | ||
da0efe30 MS |
3946 | if (unlikely(mem_cgroup_is_root(memcg))) |
3947 | return 0; | |
d6441637 | 3948 | |
bf4f0599 | 3949 | objcg = obj_cgroup_alloc(); |
f9c69d63 | 3950 | if (!objcg) |
bf4f0599 | 3951 | return -ENOMEM; |
f9c69d63 | 3952 | |
bf4f0599 RG |
3953 | objcg->memcg = memcg; |
3954 | rcu_assign_pointer(memcg->objcg, objcg); | |
675d6c9b RG |
3955 | obj_cgroup_get(objcg); |
3956 | memcg->orig_objcg = objcg; | |
bf4f0599 | 3957 | |
f7a449f7 | 3958 | static_branch_enable(&memcg_kmem_online_key); |
d648bcc7 | 3959 | |
f9c69d63 | 3960 | memcg->kmemcg_id = memcg->id.id; |
0b8f73e1 JW |
3961 | |
3962 | return 0; | |
d6441637 VD |
3963 | } |
3964 | ||
8e0a8912 JW |
3965 | static void memcg_offline_kmem(struct mem_cgroup *memcg) |
3966 | { | |
64268868 | 3967 | struct mem_cgroup *parent; |
8e0a8912 | 3968 | |
9c94bef9 | 3969 | if (mem_cgroup_kmem_disabled()) |
da0efe30 MS |
3970 | return; |
3971 | ||
3972 | if (unlikely(mem_cgroup_is_root(memcg))) | |
8e0a8912 | 3973 | return; |
9855609b | 3974 | |
8e0a8912 JW |
3975 | parent = parent_mem_cgroup(memcg); |
3976 | if (!parent) | |
3977 | parent = root_mem_cgroup; | |
3978 | ||
bf4f0599 | 3979 | memcg_reparent_objcgs(memcg, parent); |
fb2f2b0a | 3980 | |
8e0a8912 | 3981 | /* |
64268868 MS |
3982 | * After we have finished memcg_reparent_objcgs(), all list_lrus |
3983 | * corresponding to this cgroup are guaranteed to remain empty. | |
3984 | * The ordering is imposed by list_lru_node->lock taken by | |
1f391eb2 | 3985 | * memcg_reparent_list_lrus(). |
8e0a8912 | 3986 | */ |
1f391eb2 | 3987 | memcg_reparent_list_lrus(memcg, parent); |
8e0a8912 | 3988 | } |
d6441637 | 3989 | #else |
0b8f73e1 | 3990 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
127424c8 JW |
3991 | { |
3992 | return 0; | |
3993 | } | |
3994 | static void memcg_offline_kmem(struct mem_cgroup *memcg) | |
3995 | { | |
3996 | } | |
84c07d11 | 3997 | #endif /* CONFIG_MEMCG_KMEM */ |
127424c8 | 3998 | |
bbec2e15 | 3999 | static int memcg_update_tcp_max(struct mem_cgroup *memcg, unsigned long max) |
d55f90bf VD |
4000 | { |
4001 | int ret; | |
4002 | ||
bbec2e15 | 4003 | mutex_lock(&memcg_max_mutex); |
d55f90bf | 4004 | |
bbec2e15 | 4005 | ret = page_counter_set_max(&memcg->tcpmem, max); |
d55f90bf VD |
4006 | if (ret) |
4007 | goto out; | |
4008 | ||
0db15298 | 4009 | if (!memcg->tcpmem_active) { |
d55f90bf VD |
4010 | /* |
4011 | * The active flag needs to be written after the static_key | |
4012 | * update. This is what guarantees that the socket activation | |
2d758073 JW |
4013 | * function is the last one to run. See mem_cgroup_sk_alloc() |
4014 | * for details, and note that we don't mark any socket as | |
4015 | * belonging to this memcg until that flag is up. | |
d55f90bf VD |
4016 | * |
4017 | * We need to do this, because static_keys will span multiple | |
4018 | * sites, but we can't control their order. If we mark a socket | |
4019 | * as accounted, but the accounting functions are not patched in | |
4020 | * yet, we'll lose accounting. | |
4021 | * | |
2d758073 | 4022 | * We never race with the readers in mem_cgroup_sk_alloc(), |
d55f90bf VD |
4023 | * because when this value change, the code to process it is not |
4024 | * patched in yet. | |
4025 | */ | |
4026 | static_branch_inc(&memcg_sockets_enabled_key); | |
0db15298 | 4027 | memcg->tcpmem_active = true; |
d55f90bf VD |
4028 | } |
4029 | out: | |
bbec2e15 | 4030 | mutex_unlock(&memcg_max_mutex); |
d55f90bf VD |
4031 | return ret; |
4032 | } | |
d55f90bf | 4033 | |
628f4235 KH |
4034 | /* |
4035 | * The user of this function is... | |
4036 | * RES_LIMIT. | |
4037 | */ | |
451af504 TH |
4038 | static ssize_t mem_cgroup_write(struct kernfs_open_file *of, |
4039 | char *buf, size_t nbytes, loff_t off) | |
8cdea7c0 | 4040 | { |
451af504 | 4041 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 4042 | unsigned long nr_pages; |
628f4235 KH |
4043 | int ret; |
4044 | ||
451af504 | 4045 | buf = strstrip(buf); |
650c5e56 | 4046 | ret = page_counter_memparse(buf, "-1", &nr_pages); |
3e32cb2e JW |
4047 | if (ret) |
4048 | return ret; | |
af36f906 | 4049 | |
3e32cb2e | 4050 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
628f4235 | 4051 | case RES_LIMIT: |
4b3bde4c BS |
4052 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
4053 | ret = -EINVAL; | |
4054 | break; | |
4055 | } | |
3e32cb2e JW |
4056 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
4057 | case _MEM: | |
bbec2e15 | 4058 | ret = mem_cgroup_resize_max(memcg, nr_pages, false); |
8c7c6e34 | 4059 | break; |
3e32cb2e | 4060 | case _MEMSWAP: |
bbec2e15 | 4061 | ret = mem_cgroup_resize_max(memcg, nr_pages, true); |
296c81d8 | 4062 | break; |
4597648f MH |
4063 | case _KMEM: |
4064 | pr_warn_once("kmem.limit_in_bytes is deprecated and will be removed. " | |
4065 | "Writing any value to this file has no effect. " | |
4066 | "Please report your usecase to linux-mm@kvack.org if you " | |
4067 | "depend on this functionality.\n"); | |
4068 | ret = 0; | |
4069 | break; | |
d55f90bf | 4070 | case _TCP: |
bbec2e15 | 4071 | ret = memcg_update_tcp_max(memcg, nr_pages); |
d55f90bf | 4072 | break; |
3e32cb2e | 4073 | } |
296c81d8 | 4074 | break; |
3e32cb2e | 4075 | case RES_SOFT_LIMIT: |
2343e88d SAS |
4076 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) { |
4077 | ret = -EOPNOTSUPP; | |
4078 | } else { | |
2178e20c | 4079 | WRITE_ONCE(memcg->soft_limit, nr_pages); |
2343e88d SAS |
4080 | ret = 0; |
4081 | } | |
628f4235 KH |
4082 | break; |
4083 | } | |
451af504 | 4084 | return ret ?: nbytes; |
8cdea7c0 BS |
4085 | } |
4086 | ||
6770c64e TH |
4087 | static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf, |
4088 | size_t nbytes, loff_t off) | |
c84872e1 | 4089 | { |
6770c64e | 4090 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 4091 | struct page_counter *counter; |
c84872e1 | 4092 | |
3e32cb2e JW |
4093 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
4094 | case _MEM: | |
4095 | counter = &memcg->memory; | |
4096 | break; | |
4097 | case _MEMSWAP: | |
4098 | counter = &memcg->memsw; | |
4099 | break; | |
4100 | case _KMEM: | |
4101 | counter = &memcg->kmem; | |
4102 | break; | |
d55f90bf | 4103 | case _TCP: |
0db15298 | 4104 | counter = &memcg->tcpmem; |
d55f90bf | 4105 | break; |
3e32cb2e JW |
4106 | default: |
4107 | BUG(); | |
4108 | } | |
af36f906 | 4109 | |
3e32cb2e | 4110 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
29f2a4da | 4111 | case RES_MAX_USAGE: |
3e32cb2e | 4112 | page_counter_reset_watermark(counter); |
29f2a4da PE |
4113 | break; |
4114 | case RES_FAILCNT: | |
3e32cb2e | 4115 | counter->failcnt = 0; |
29f2a4da | 4116 | break; |
3e32cb2e JW |
4117 | default: |
4118 | BUG(); | |
29f2a4da | 4119 | } |
f64c3f54 | 4120 | |
6770c64e | 4121 | return nbytes; |
c84872e1 PE |
4122 | } |
4123 | ||
182446d0 | 4124 | static u64 mem_cgroup_move_charge_read(struct cgroup_subsys_state *css, |
7dc74be0 DN |
4125 | struct cftype *cft) |
4126 | { | |
182446d0 | 4127 | return mem_cgroup_from_css(css)->move_charge_at_immigrate; |
7dc74be0 DN |
4128 | } |
4129 | ||
02491447 | 4130 | #ifdef CONFIG_MMU |
182446d0 | 4131 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
7dc74be0 DN |
4132 | struct cftype *cft, u64 val) |
4133 | { | |
182446d0 | 4134 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
7dc74be0 | 4135 | |
da34a848 JW |
4136 | pr_warn_once("Cgroup memory moving (move_charge_at_immigrate) is deprecated. " |
4137 | "Please report your usecase to linux-mm@kvack.org if you " | |
4138 | "depend on this functionality.\n"); | |
4139 | ||
1dfab5ab | 4140 | if (val & ~MOVE_MASK) |
7dc74be0 | 4141 | return -EINVAL; |
ee5e8472 | 4142 | |
7dc74be0 | 4143 | /* |
ee5e8472 GC |
4144 | * No kind of locking is needed in here, because ->can_attach() will |
4145 | * check this value once in the beginning of the process, and then carry | |
4146 | * on with stale data. This means that changes to this value will only | |
4147 | * affect task migrations starting after the change. | |
7dc74be0 | 4148 | */ |
c0ff4b85 | 4149 | memcg->move_charge_at_immigrate = val; |
7dc74be0 DN |
4150 | return 0; |
4151 | } | |
02491447 | 4152 | #else |
182446d0 | 4153 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
02491447 DN |
4154 | struct cftype *cft, u64 val) |
4155 | { | |
4156 | return -ENOSYS; | |
4157 | } | |
4158 | #endif | |
7dc74be0 | 4159 | |
406eb0c9 | 4160 | #ifdef CONFIG_NUMA |
113b7dfd JW |
4161 | |
4162 | #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE)) | |
4163 | #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON)) | |
4164 | #define LRU_ALL ((1 << NR_LRU_LISTS) - 1) | |
4165 | ||
4166 | static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, | |
dd8657b6 | 4167 | int nid, unsigned int lru_mask, bool tree) |
113b7dfd | 4168 | { |
867e5e1d | 4169 | struct lruvec *lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); |
113b7dfd JW |
4170 | unsigned long nr = 0; |
4171 | enum lru_list lru; | |
4172 | ||
4173 | VM_BUG_ON((unsigned)nid >= nr_node_ids); | |
4174 | ||
4175 | for_each_lru(lru) { | |
4176 | if (!(BIT(lru) & lru_mask)) | |
4177 | continue; | |
dd8657b6 SB |
4178 | if (tree) |
4179 | nr += lruvec_page_state(lruvec, NR_LRU_BASE + lru); | |
4180 | else | |
4181 | nr += lruvec_page_state_local(lruvec, NR_LRU_BASE + lru); | |
113b7dfd JW |
4182 | } |
4183 | return nr; | |
4184 | } | |
4185 | ||
4186 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, | |
dd8657b6 SB |
4187 | unsigned int lru_mask, |
4188 | bool tree) | |
113b7dfd JW |
4189 | { |
4190 | unsigned long nr = 0; | |
4191 | enum lru_list lru; | |
4192 | ||
4193 | for_each_lru(lru) { | |
4194 | if (!(BIT(lru) & lru_mask)) | |
4195 | continue; | |
dd8657b6 SB |
4196 | if (tree) |
4197 | nr += memcg_page_state(memcg, NR_LRU_BASE + lru); | |
4198 | else | |
4199 | nr += memcg_page_state_local(memcg, NR_LRU_BASE + lru); | |
113b7dfd JW |
4200 | } |
4201 | return nr; | |
4202 | } | |
4203 | ||
2da8ca82 | 4204 | static int memcg_numa_stat_show(struct seq_file *m, void *v) |
406eb0c9 | 4205 | { |
25485de6 GT |
4206 | struct numa_stat { |
4207 | const char *name; | |
4208 | unsigned int lru_mask; | |
4209 | }; | |
4210 | ||
4211 | static const struct numa_stat stats[] = { | |
4212 | { "total", LRU_ALL }, | |
4213 | { "file", LRU_ALL_FILE }, | |
4214 | { "anon", LRU_ALL_ANON }, | |
4215 | { "unevictable", BIT(LRU_UNEVICTABLE) }, | |
4216 | }; | |
4217 | const struct numa_stat *stat; | |
406eb0c9 | 4218 | int nid; |
aa9694bb | 4219 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
406eb0c9 | 4220 | |
7d7ef0a4 | 4221 | mem_cgroup_flush_stats(memcg); |
2d146aa3 | 4222 | |
25485de6 | 4223 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
dd8657b6 SB |
4224 | seq_printf(m, "%s=%lu", stat->name, |
4225 | mem_cgroup_nr_lru_pages(memcg, stat->lru_mask, | |
4226 | false)); | |
4227 | for_each_node_state(nid, N_MEMORY) | |
4228 | seq_printf(m, " N%d=%lu", nid, | |
4229 | mem_cgroup_node_nr_lru_pages(memcg, nid, | |
4230 | stat->lru_mask, false)); | |
25485de6 | 4231 | seq_putc(m, '\n'); |
406eb0c9 | 4232 | } |
406eb0c9 | 4233 | |
071aee13 | 4234 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
dd8657b6 SB |
4235 | |
4236 | seq_printf(m, "hierarchical_%s=%lu", stat->name, | |
4237 | mem_cgroup_nr_lru_pages(memcg, stat->lru_mask, | |
4238 | true)); | |
4239 | for_each_node_state(nid, N_MEMORY) | |
4240 | seq_printf(m, " N%d=%lu", nid, | |
4241 | mem_cgroup_node_nr_lru_pages(memcg, nid, | |
4242 | stat->lru_mask, true)); | |
071aee13 | 4243 | seq_putc(m, '\n'); |
406eb0c9 | 4244 | } |
406eb0c9 | 4245 | |
406eb0c9 YH |
4246 | return 0; |
4247 | } | |
4248 | #endif /* CONFIG_NUMA */ | |
4249 | ||
c8713d0b | 4250 | static const unsigned int memcg1_stats[] = { |
0d1c2072 | 4251 | NR_FILE_PAGES, |
be5d0a74 | 4252 | NR_ANON_MAPPED, |
468c3982 JW |
4253 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
4254 | NR_ANON_THPS, | |
4255 | #endif | |
c8713d0b JW |
4256 | NR_SHMEM, |
4257 | NR_FILE_MAPPED, | |
4258 | NR_FILE_DIRTY, | |
4259 | NR_WRITEBACK, | |
e09b0b61 YS |
4260 | WORKINGSET_REFAULT_ANON, |
4261 | WORKINGSET_REFAULT_FILE, | |
72a14e82 | 4262 | #ifdef CONFIG_SWAP |
c8713d0b | 4263 | MEMCG_SWAP, |
72a14e82 LS |
4264 | NR_SWAPCACHE, |
4265 | #endif | |
c8713d0b JW |
4266 | }; |
4267 | ||
4268 | static const char *const memcg1_stat_names[] = { | |
4269 | "cache", | |
4270 | "rss", | |
468c3982 | 4271 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
c8713d0b | 4272 | "rss_huge", |
468c3982 | 4273 | #endif |
c8713d0b JW |
4274 | "shmem", |
4275 | "mapped_file", | |
4276 | "dirty", | |
4277 | "writeback", | |
e09b0b61 YS |
4278 | "workingset_refault_anon", |
4279 | "workingset_refault_file", | |
72a14e82 | 4280 | #ifdef CONFIG_SWAP |
c8713d0b | 4281 | "swap", |
72a14e82 LS |
4282 | "swapcached", |
4283 | #endif | |
c8713d0b JW |
4284 | }; |
4285 | ||
df0e53d0 | 4286 | /* Universal VM events cgroup1 shows, original sort order */ |
8dd53fd3 | 4287 | static const unsigned int memcg1_events[] = { |
df0e53d0 JW |
4288 | PGPGIN, |
4289 | PGPGOUT, | |
4290 | PGFAULT, | |
4291 | PGMAJFAULT, | |
4292 | }; | |
4293 | ||
dddb44ff | 4294 | static void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) |
d2ceb9b7 | 4295 | { |
3e32cb2e | 4296 | unsigned long memory, memsw; |
af7c4b0e JW |
4297 | struct mem_cgroup *mi; |
4298 | unsigned int i; | |
406eb0c9 | 4299 | |
71cd3113 | 4300 | BUILD_BUG_ON(ARRAY_SIZE(memcg1_stat_names) != ARRAY_SIZE(memcg1_stats)); |
70bc068c | 4301 | |
7d7ef0a4 | 4302 | mem_cgroup_flush_stats(memcg); |
2d146aa3 | 4303 | |
71cd3113 | 4304 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
468c3982 JW |
4305 | unsigned long nr; |
4306 | ||
ff841a06 YA |
4307 | nr = memcg_page_state_local_output(memcg, memcg1_stats[i]); |
4308 | seq_buf_printf(s, "%s %lu\n", memcg1_stat_names[i], nr); | |
1dd3a273 | 4309 | } |
7b854121 | 4310 | |
df0e53d0 | 4311 | for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) |
dddb44ff YA |
4312 | seq_buf_printf(s, "%s %lu\n", vm_event_name(memcg1_events[i]), |
4313 | memcg_events_local(memcg, memcg1_events[i])); | |
af7c4b0e JW |
4314 | |
4315 | for (i = 0; i < NR_LRU_LISTS; i++) | |
dddb44ff YA |
4316 | seq_buf_printf(s, "%s %lu\n", lru_list_name(i), |
4317 | memcg_page_state_local(memcg, NR_LRU_BASE + i) * | |
4318 | PAGE_SIZE); | |
af7c4b0e | 4319 | |
14067bb3 | 4320 | /* Hierarchical information */ |
3e32cb2e JW |
4321 | memory = memsw = PAGE_COUNTER_MAX; |
4322 | for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) { | |
15b42562 CD |
4323 | memory = min(memory, READ_ONCE(mi->memory.max)); |
4324 | memsw = min(memsw, READ_ONCE(mi->memsw.max)); | |
fee7b548 | 4325 | } |
dddb44ff YA |
4326 | seq_buf_printf(s, "hierarchical_memory_limit %llu\n", |
4327 | (u64)memory * PAGE_SIZE); | |
840ea53a LS |
4328 | seq_buf_printf(s, "hierarchical_memsw_limit %llu\n", |
4329 | (u64)memsw * PAGE_SIZE); | |
7f016ee8 | 4330 | |
8de7ecc6 | 4331 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
7de2e9f1 | 4332 | unsigned long nr; |
4333 | ||
ff841a06 | 4334 | nr = memcg_page_state_output(memcg, memcg1_stats[i]); |
dddb44ff | 4335 | seq_buf_printf(s, "total_%s %llu\n", memcg1_stat_names[i], |
ff841a06 | 4336 | (u64)nr); |
af7c4b0e JW |
4337 | } |
4338 | ||
8de7ecc6 | 4339 | for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) |
dddb44ff YA |
4340 | seq_buf_printf(s, "total_%s %llu\n", |
4341 | vm_event_name(memcg1_events[i]), | |
4342 | (u64)memcg_events(memcg, memcg1_events[i])); | |
af7c4b0e | 4343 | |
8de7ecc6 | 4344 | for (i = 0; i < NR_LRU_LISTS; i++) |
dddb44ff YA |
4345 | seq_buf_printf(s, "total_%s %llu\n", lru_list_name(i), |
4346 | (u64)memcg_page_state(memcg, NR_LRU_BASE + i) * | |
4347 | PAGE_SIZE); | |
14067bb3 | 4348 | |
7f016ee8 | 4349 | #ifdef CONFIG_DEBUG_VM |
7f016ee8 | 4350 | { |
ef8f2327 MG |
4351 | pg_data_t *pgdat; |
4352 | struct mem_cgroup_per_node *mz; | |
1431d4d1 JW |
4353 | unsigned long anon_cost = 0; |
4354 | unsigned long file_cost = 0; | |
7f016ee8 | 4355 | |
ef8f2327 | 4356 | for_each_online_pgdat(pgdat) { |
a3747b53 | 4357 | mz = memcg->nodeinfo[pgdat->node_id]; |
7f016ee8 | 4358 | |
1431d4d1 JW |
4359 | anon_cost += mz->lruvec.anon_cost; |
4360 | file_cost += mz->lruvec.file_cost; | |
ef8f2327 | 4361 | } |
dddb44ff YA |
4362 | seq_buf_printf(s, "anon_cost %lu\n", anon_cost); |
4363 | seq_buf_printf(s, "file_cost %lu\n", file_cost); | |
7f016ee8 KM |
4364 | } |
4365 | #endif | |
d2ceb9b7 KH |
4366 | } |
4367 | ||
182446d0 TH |
4368 | static u64 mem_cgroup_swappiness_read(struct cgroup_subsys_state *css, |
4369 | struct cftype *cft) | |
a7885eb8 | 4370 | { |
182446d0 | 4371 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 4372 | |
1f4c025b | 4373 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
4374 | } |
4375 | ||
182446d0 TH |
4376 | static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, |
4377 | struct cftype *cft, u64 val) | |
a7885eb8 | 4378 | { |
182446d0 | 4379 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 4380 | |
37bc3cb9 | 4381 | if (val > 200) |
a7885eb8 KM |
4382 | return -EINVAL; |
4383 | ||
a4792030 | 4384 | if (!mem_cgroup_is_root(memcg)) |
82b3aa26 | 4385 | WRITE_ONCE(memcg->swappiness, val); |
3dae7fec | 4386 | else |
82b3aa26 | 4387 | WRITE_ONCE(vm_swappiness, val); |
068b38c1 | 4388 | |
a7885eb8 KM |
4389 | return 0; |
4390 | } | |
4391 | ||
2e72b634 KS |
4392 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
4393 | { | |
4394 | struct mem_cgroup_threshold_ary *t; | |
3e32cb2e | 4395 | unsigned long usage; |
2e72b634 KS |
4396 | int i; |
4397 | ||
4398 | rcu_read_lock(); | |
4399 | if (!swap) | |
2c488db2 | 4400 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 4401 | else |
2c488db2 | 4402 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
4403 | |
4404 | if (!t) | |
4405 | goto unlock; | |
4406 | ||
ce00a967 | 4407 | usage = mem_cgroup_usage(memcg, swap); |
2e72b634 KS |
4408 | |
4409 | /* | |
748dad36 | 4410 | * current_threshold points to threshold just below or equal to usage. |
2e72b634 KS |
4411 | * If it's not true, a threshold was crossed after last |
4412 | * call of __mem_cgroup_threshold(). | |
4413 | */ | |
5407a562 | 4414 | i = t->current_threshold; |
2e72b634 KS |
4415 | |
4416 | /* | |
4417 | * Iterate backward over array of thresholds starting from | |
4418 | * current_threshold and check if a threshold is crossed. | |
4419 | * If none of thresholds below usage is crossed, we read | |
4420 | * only one element of the array here. | |
4421 | */ | |
4422 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
3652117f | 4423 | eventfd_signal(t->entries[i].eventfd); |
2e72b634 KS |
4424 | |
4425 | /* i = current_threshold + 1 */ | |
4426 | i++; | |
4427 | ||
4428 | /* | |
4429 | * Iterate forward over array of thresholds starting from | |
4430 | * current_threshold+1 and check if a threshold is crossed. | |
4431 | * If none of thresholds above usage is crossed, we read | |
4432 | * only one element of the array here. | |
4433 | */ | |
4434 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
3652117f | 4435 | eventfd_signal(t->entries[i].eventfd); |
2e72b634 KS |
4436 | |
4437 | /* Update current_threshold */ | |
5407a562 | 4438 | t->current_threshold = i - 1; |
2e72b634 KS |
4439 | unlock: |
4440 | rcu_read_unlock(); | |
4441 | } | |
4442 | ||
4443 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
4444 | { | |
ad4ca5f4 KS |
4445 | while (memcg) { |
4446 | __mem_cgroup_threshold(memcg, false); | |
7941d214 | 4447 | if (do_memsw_account()) |
ad4ca5f4 KS |
4448 | __mem_cgroup_threshold(memcg, true); |
4449 | ||
4450 | memcg = parent_mem_cgroup(memcg); | |
4451 | } | |
2e72b634 KS |
4452 | } |
4453 | ||
4454 | static int compare_thresholds(const void *a, const void *b) | |
4455 | { | |
4456 | const struct mem_cgroup_threshold *_a = a; | |
4457 | const struct mem_cgroup_threshold *_b = b; | |
4458 | ||
2bff24a3 GT |
4459 | if (_a->threshold > _b->threshold) |
4460 | return 1; | |
4461 | ||
4462 | if (_a->threshold < _b->threshold) | |
4463 | return -1; | |
4464 | ||
4465 | return 0; | |
2e72b634 KS |
4466 | } |
4467 | ||
c0ff4b85 | 4468 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg) |
9490ff27 KH |
4469 | { |
4470 | struct mem_cgroup_eventfd_list *ev; | |
4471 | ||
2bcf2e92 MH |
4472 | spin_lock(&memcg_oom_lock); |
4473 | ||
c0ff4b85 | 4474 | list_for_each_entry(ev, &memcg->oom_notify, list) |
3652117f | 4475 | eventfd_signal(ev->eventfd); |
2bcf2e92 MH |
4476 | |
4477 | spin_unlock(&memcg_oom_lock); | |
9490ff27 KH |
4478 | return 0; |
4479 | } | |
4480 | ||
c0ff4b85 | 4481 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) |
9490ff27 | 4482 | { |
7d74b06f KH |
4483 | struct mem_cgroup *iter; |
4484 | ||
c0ff4b85 | 4485 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 4486 | mem_cgroup_oom_notify_cb(iter); |
9490ff27 KH |
4487 | } |
4488 | ||
59b6f873 | 4489 | static int __mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 | 4490 | struct eventfd_ctx *eventfd, const char *args, enum res_type type) |
2e72b634 | 4491 | { |
2c488db2 KS |
4492 | struct mem_cgroup_thresholds *thresholds; |
4493 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e JW |
4494 | unsigned long threshold; |
4495 | unsigned long usage; | |
2c488db2 | 4496 | int i, size, ret; |
2e72b634 | 4497 | |
650c5e56 | 4498 | ret = page_counter_memparse(args, "-1", &threshold); |
2e72b634 KS |
4499 | if (ret) |
4500 | return ret; | |
4501 | ||
4502 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 4503 | |
05b84301 | 4504 | if (type == _MEM) { |
2c488db2 | 4505 | thresholds = &memcg->thresholds; |
ce00a967 | 4506 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 4507 | } else if (type == _MEMSWAP) { |
2c488db2 | 4508 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 4509 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 4510 | } else |
2e72b634 KS |
4511 | BUG(); |
4512 | ||
2e72b634 | 4513 | /* Check if a threshold crossed before adding a new one */ |
2c488db2 | 4514 | if (thresholds->primary) |
2e72b634 KS |
4515 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4516 | ||
2c488db2 | 4517 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
4518 | |
4519 | /* Allocate memory for new array of thresholds */ | |
67b8046f | 4520 | new = kmalloc(struct_size(new, entries, size), GFP_KERNEL); |
2c488db2 | 4521 | if (!new) { |
2e72b634 KS |
4522 | ret = -ENOMEM; |
4523 | goto unlock; | |
4524 | } | |
2c488db2 | 4525 | new->size = size; |
2e72b634 KS |
4526 | |
4527 | /* Copy thresholds (if any) to new array */ | |
e90342e6 GS |
4528 | if (thresholds->primary) |
4529 | memcpy(new->entries, thresholds->primary->entries, | |
4530 | flex_array_size(new, entries, size - 1)); | |
2c488db2 | 4531 | |
2e72b634 | 4532 | /* Add new threshold */ |
2c488db2 KS |
4533 | new->entries[size - 1].eventfd = eventfd; |
4534 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
4535 | |
4536 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
61e604e6 | 4537 | sort(new->entries, size, sizeof(*new->entries), |
2e72b634 KS |
4538 | compare_thresholds, NULL); |
4539 | ||
4540 | /* Find current threshold */ | |
2c488db2 | 4541 | new->current_threshold = -1; |
2e72b634 | 4542 | for (i = 0; i < size; i++) { |
748dad36 | 4543 | if (new->entries[i].threshold <= usage) { |
2e72b634 | 4544 | /* |
2c488db2 KS |
4545 | * new->current_threshold will not be used until |
4546 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
4547 | * it here. |
4548 | */ | |
2c488db2 | 4549 | ++new->current_threshold; |
748dad36 SZ |
4550 | } else |
4551 | break; | |
2e72b634 KS |
4552 | } |
4553 | ||
2c488db2 KS |
4554 | /* Free old spare buffer and save old primary buffer as spare */ |
4555 | kfree(thresholds->spare); | |
4556 | thresholds->spare = thresholds->primary; | |
4557 | ||
4558 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4559 | |
907860ed | 4560 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4561 | synchronize_rcu(); |
4562 | ||
2e72b634 KS |
4563 | unlock: |
4564 | mutex_unlock(&memcg->thresholds_lock); | |
4565 | ||
4566 | return ret; | |
4567 | } | |
4568 | ||
59b6f873 | 4569 | static int mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4570 | struct eventfd_ctx *eventfd, const char *args) |
4571 | { | |
59b6f873 | 4572 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEM); |
347c4a87 TH |
4573 | } |
4574 | ||
59b6f873 | 4575 | static int memsw_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4576 | struct eventfd_ctx *eventfd, const char *args) |
4577 | { | |
59b6f873 | 4578 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEMSWAP); |
347c4a87 TH |
4579 | } |
4580 | ||
59b6f873 | 4581 | static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 4582 | struct eventfd_ctx *eventfd, enum res_type type) |
2e72b634 | 4583 | { |
2c488db2 KS |
4584 | struct mem_cgroup_thresholds *thresholds; |
4585 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e | 4586 | unsigned long usage; |
7d36665a | 4587 | int i, j, size, entries; |
2e72b634 KS |
4588 | |
4589 | mutex_lock(&memcg->thresholds_lock); | |
05b84301 JW |
4590 | |
4591 | if (type == _MEM) { | |
2c488db2 | 4592 | thresholds = &memcg->thresholds; |
ce00a967 | 4593 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 4594 | } else if (type == _MEMSWAP) { |
2c488db2 | 4595 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 4596 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 4597 | } else |
2e72b634 KS |
4598 | BUG(); |
4599 | ||
371528ca AV |
4600 | if (!thresholds->primary) |
4601 | goto unlock; | |
4602 | ||
2e72b634 KS |
4603 | /* Check if a threshold crossed before removing */ |
4604 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
4605 | ||
4606 | /* Calculate new number of threshold */ | |
7d36665a | 4607 | size = entries = 0; |
2c488db2 KS |
4608 | for (i = 0; i < thresholds->primary->size; i++) { |
4609 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 | 4610 | size++; |
7d36665a CX |
4611 | else |
4612 | entries++; | |
2e72b634 KS |
4613 | } |
4614 | ||
2c488db2 | 4615 | new = thresholds->spare; |
907860ed | 4616 | |
7d36665a CX |
4617 | /* If no items related to eventfd have been cleared, nothing to do */ |
4618 | if (!entries) | |
4619 | goto unlock; | |
4620 | ||
2e72b634 KS |
4621 | /* Set thresholds array to NULL if we don't have thresholds */ |
4622 | if (!size) { | |
2c488db2 KS |
4623 | kfree(new); |
4624 | new = NULL; | |
907860ed | 4625 | goto swap_buffers; |
2e72b634 KS |
4626 | } |
4627 | ||
2c488db2 | 4628 | new->size = size; |
2e72b634 KS |
4629 | |
4630 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
4631 | new->current_threshold = -1; |
4632 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
4633 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
4634 | continue; |
4635 | ||
2c488db2 | 4636 | new->entries[j] = thresholds->primary->entries[i]; |
748dad36 | 4637 | if (new->entries[j].threshold <= usage) { |
2e72b634 | 4638 | /* |
2c488db2 | 4639 | * new->current_threshold will not be used |
2e72b634 KS |
4640 | * until rcu_assign_pointer(), so it's safe to increment |
4641 | * it here. | |
4642 | */ | |
2c488db2 | 4643 | ++new->current_threshold; |
2e72b634 KS |
4644 | } |
4645 | j++; | |
4646 | } | |
4647 | ||
907860ed | 4648 | swap_buffers: |
2c488db2 KS |
4649 | /* Swap primary and spare array */ |
4650 | thresholds->spare = thresholds->primary; | |
8c757763 | 4651 | |
2c488db2 | 4652 | rcu_assign_pointer(thresholds->primary, new); |
2e72b634 | 4653 | |
907860ed | 4654 | /* To be sure that nobody uses thresholds */ |
2e72b634 | 4655 | synchronize_rcu(); |
6611d8d7 MC |
4656 | |
4657 | /* If all events are unregistered, free the spare array */ | |
4658 | if (!new) { | |
4659 | kfree(thresholds->spare); | |
4660 | thresholds->spare = NULL; | |
4661 | } | |
371528ca | 4662 | unlock: |
2e72b634 | 4663 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 4664 | } |
c1e862c1 | 4665 | |
59b6f873 | 4666 | static void mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4667 | struct eventfd_ctx *eventfd) |
4668 | { | |
59b6f873 | 4669 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEM); |
347c4a87 TH |
4670 | } |
4671 | ||
59b6f873 | 4672 | static void memsw_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4673 | struct eventfd_ctx *eventfd) |
4674 | { | |
59b6f873 | 4675 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEMSWAP); |
347c4a87 TH |
4676 | } |
4677 | ||
59b6f873 | 4678 | static int mem_cgroup_oom_register_event(struct mem_cgroup *memcg, |
347c4a87 | 4679 | struct eventfd_ctx *eventfd, const char *args) |
9490ff27 | 4680 | { |
9490ff27 | 4681 | struct mem_cgroup_eventfd_list *event; |
9490ff27 | 4682 | |
9490ff27 KH |
4683 | event = kmalloc(sizeof(*event), GFP_KERNEL); |
4684 | if (!event) | |
4685 | return -ENOMEM; | |
4686 | ||
1af8efe9 | 4687 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4688 | |
4689 | event->eventfd = eventfd; | |
4690 | list_add(&event->list, &memcg->oom_notify); | |
4691 | ||
4692 | /* already in OOM ? */ | |
c2b42d3c | 4693 | if (memcg->under_oom) |
3652117f | 4694 | eventfd_signal(eventfd); |
1af8efe9 | 4695 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4696 | |
4697 | return 0; | |
4698 | } | |
4699 | ||
59b6f873 | 4700 | static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 4701 | struct eventfd_ctx *eventfd) |
9490ff27 | 4702 | { |
9490ff27 | 4703 | struct mem_cgroup_eventfd_list *ev, *tmp; |
9490ff27 | 4704 | |
1af8efe9 | 4705 | spin_lock(&memcg_oom_lock); |
9490ff27 | 4706 | |
c0ff4b85 | 4707 | list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) { |
9490ff27 KH |
4708 | if (ev->eventfd == eventfd) { |
4709 | list_del(&ev->list); | |
4710 | kfree(ev); | |
4711 | } | |
4712 | } | |
4713 | ||
1af8efe9 | 4714 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4715 | } |
4716 | ||
2da8ca82 | 4717 | static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v) |
3c11ecf4 | 4718 | { |
aa9694bb | 4719 | struct mem_cgroup *memcg = mem_cgroup_from_seq(sf); |
3c11ecf4 | 4720 | |
17c56de6 | 4721 | seq_printf(sf, "oom_kill_disable %d\n", READ_ONCE(memcg->oom_kill_disable)); |
c2b42d3c | 4722 | seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom); |
fe6bdfc8 RG |
4723 | seq_printf(sf, "oom_kill %lu\n", |
4724 | atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL])); | |
3c11ecf4 KH |
4725 | return 0; |
4726 | } | |
4727 | ||
182446d0 | 4728 | static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css, |
3c11ecf4 KH |
4729 | struct cftype *cft, u64 val) |
4730 | { | |
182446d0 | 4731 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3c11ecf4 KH |
4732 | |
4733 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
a4792030 | 4734 | if (mem_cgroup_is_root(memcg) || !((val == 0) || (val == 1))) |
3c11ecf4 KH |
4735 | return -EINVAL; |
4736 | ||
17c56de6 | 4737 | WRITE_ONCE(memcg->oom_kill_disable, val); |
4d845ebf | 4738 | if (!val) |
c0ff4b85 | 4739 | memcg_oom_recover(memcg); |
3dae7fec | 4740 | |
3c11ecf4 KH |
4741 | return 0; |
4742 | } | |
4743 | ||
52ebea74 TH |
4744 | #ifdef CONFIG_CGROUP_WRITEBACK |
4745 | ||
3a8e9ac8 TH |
4746 | #include <trace/events/writeback.h> |
4747 | ||
841710aa TH |
4748 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) |
4749 | { | |
4750 | return wb_domain_init(&memcg->cgwb_domain, gfp); | |
4751 | } | |
4752 | ||
4753 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
4754 | { | |
4755 | wb_domain_exit(&memcg->cgwb_domain); | |
4756 | } | |
4757 | ||
2529bb3a TH |
4758 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
4759 | { | |
4760 | wb_domain_size_changed(&memcg->cgwb_domain); | |
4761 | } | |
4762 | ||
841710aa TH |
4763 | struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb) |
4764 | { | |
4765 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4766 | ||
4767 | if (!memcg->css.parent) | |
4768 | return NULL; | |
4769 | ||
4770 | return &memcg->cgwb_domain; | |
4771 | } | |
4772 | ||
c2aa723a TH |
4773 | /** |
4774 | * mem_cgroup_wb_stats - retrieve writeback related stats from its memcg | |
4775 | * @wb: bdi_writeback in question | |
c5edf9cd TH |
4776 | * @pfilepages: out parameter for number of file pages |
4777 | * @pheadroom: out parameter for number of allocatable pages according to memcg | |
c2aa723a TH |
4778 | * @pdirty: out parameter for number of dirty pages |
4779 | * @pwriteback: out parameter for number of pages under writeback | |
4780 | * | |
c5edf9cd TH |
4781 | * Determine the numbers of file, headroom, dirty, and writeback pages in |
4782 | * @wb's memcg. File, dirty and writeback are self-explanatory. Headroom | |
4783 | * is a bit more involved. | |
c2aa723a | 4784 | * |
c5edf9cd TH |
4785 | * A memcg's headroom is "min(max, high) - used". In the hierarchy, the |
4786 | * headroom is calculated as the lowest headroom of itself and the | |
4787 | * ancestors. Note that this doesn't consider the actual amount of | |
4788 | * available memory in the system. The caller should further cap | |
4789 | * *@pheadroom accordingly. | |
c2aa723a | 4790 | */ |
c5edf9cd TH |
4791 | void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, |
4792 | unsigned long *pheadroom, unsigned long *pdirty, | |
4793 | unsigned long *pwriteback) | |
c2aa723a TH |
4794 | { |
4795 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4796 | struct mem_cgroup *parent; | |
c2aa723a | 4797 | |
7d7ef0a4 | 4798 | mem_cgroup_flush_stats(memcg); |
c2aa723a | 4799 | |
2d146aa3 JW |
4800 | *pdirty = memcg_page_state(memcg, NR_FILE_DIRTY); |
4801 | *pwriteback = memcg_page_state(memcg, NR_WRITEBACK); | |
4802 | *pfilepages = memcg_page_state(memcg, NR_INACTIVE_FILE) + | |
4803 | memcg_page_state(memcg, NR_ACTIVE_FILE); | |
c2aa723a | 4804 | |
2d146aa3 | 4805 | *pheadroom = PAGE_COUNTER_MAX; |
c2aa723a | 4806 | while ((parent = parent_mem_cgroup(memcg))) { |
15b42562 | 4807 | unsigned long ceiling = min(READ_ONCE(memcg->memory.max), |
d1663a90 | 4808 | READ_ONCE(memcg->memory.high)); |
c2aa723a TH |
4809 | unsigned long used = page_counter_read(&memcg->memory); |
4810 | ||
c5edf9cd | 4811 | *pheadroom = min(*pheadroom, ceiling - min(ceiling, used)); |
c2aa723a TH |
4812 | memcg = parent; |
4813 | } | |
c2aa723a TH |
4814 | } |
4815 | ||
97b27821 TH |
4816 | /* |
4817 | * Foreign dirty flushing | |
4818 | * | |
4819 | * There's an inherent mismatch between memcg and writeback. The former | |
f0953a1b | 4820 | * tracks ownership per-page while the latter per-inode. This was a |
97b27821 TH |
4821 | * deliberate design decision because honoring per-page ownership in the |
4822 | * writeback path is complicated, may lead to higher CPU and IO overheads | |
4823 | * and deemed unnecessary given that write-sharing an inode across | |
4824 | * different cgroups isn't a common use-case. | |
4825 | * | |
4826 | * Combined with inode majority-writer ownership switching, this works well | |
4827 | * enough in most cases but there are some pathological cases. For | |
4828 | * example, let's say there are two cgroups A and B which keep writing to | |
4829 | * different but confined parts of the same inode. B owns the inode and | |
4830 | * A's memory is limited far below B's. A's dirty ratio can rise enough to | |
4831 | * trigger balance_dirty_pages() sleeps but B's can be low enough to avoid | |
4832 | * triggering background writeback. A will be slowed down without a way to | |
4833 | * make writeback of the dirty pages happen. | |
4834 | * | |
f0953a1b | 4835 | * Conditions like the above can lead to a cgroup getting repeatedly and |
97b27821 | 4836 | * severely throttled after making some progress after each |
f0953a1b | 4837 | * dirty_expire_interval while the underlying IO device is almost |
97b27821 TH |
4838 | * completely idle. |
4839 | * | |
4840 | * Solving this problem completely requires matching the ownership tracking | |
4841 | * granularities between memcg and writeback in either direction. However, | |
4842 | * the more egregious behaviors can be avoided by simply remembering the | |
4843 | * most recent foreign dirtying events and initiating remote flushes on | |
4844 | * them when local writeback isn't enough to keep the memory clean enough. | |
4845 | * | |
4846 | * The following two functions implement such mechanism. When a foreign | |
4847 | * page - a page whose memcg and writeback ownerships don't match - is | |
4848 | * dirtied, mem_cgroup_track_foreign_dirty() records the inode owning | |
4849 | * bdi_writeback on the page owning memcg. When balance_dirty_pages() | |
4850 | * decides that the memcg needs to sleep due to high dirty ratio, it calls | |
4851 | * mem_cgroup_flush_foreign() which queues writeback on the recorded | |
4852 | * foreign bdi_writebacks which haven't expired. Both the numbers of | |
4853 | * recorded bdi_writebacks and concurrent in-flight foreign writebacks are | |
4854 | * limited to MEMCG_CGWB_FRN_CNT. | |
4855 | * | |
4856 | * The mechanism only remembers IDs and doesn't hold any object references. | |
4857 | * As being wrong occasionally doesn't matter, updates and accesses to the | |
4858 | * records are lockless and racy. | |
4859 | */ | |
9d8053fc | 4860 | void mem_cgroup_track_foreign_dirty_slowpath(struct folio *folio, |
97b27821 TH |
4861 | struct bdi_writeback *wb) |
4862 | { | |
9d8053fc | 4863 | struct mem_cgroup *memcg = folio_memcg(folio); |
97b27821 TH |
4864 | struct memcg_cgwb_frn *frn; |
4865 | u64 now = get_jiffies_64(); | |
4866 | u64 oldest_at = now; | |
4867 | int oldest = -1; | |
4868 | int i; | |
4869 | ||
9d8053fc | 4870 | trace_track_foreign_dirty(folio, wb); |
3a8e9ac8 | 4871 | |
97b27821 TH |
4872 | /* |
4873 | * Pick the slot to use. If there is already a slot for @wb, keep | |
4874 | * using it. If not replace the oldest one which isn't being | |
4875 | * written out. | |
4876 | */ | |
4877 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) { | |
4878 | frn = &memcg->cgwb_frn[i]; | |
4879 | if (frn->bdi_id == wb->bdi->id && | |
4880 | frn->memcg_id == wb->memcg_css->id) | |
4881 | break; | |
4882 | if (time_before64(frn->at, oldest_at) && | |
4883 | atomic_read(&frn->done.cnt) == 1) { | |
4884 | oldest = i; | |
4885 | oldest_at = frn->at; | |
4886 | } | |
4887 | } | |
4888 | ||
4889 | if (i < MEMCG_CGWB_FRN_CNT) { | |
4890 | /* | |
4891 | * Re-using an existing one. Update timestamp lazily to | |
4892 | * avoid making the cacheline hot. We want them to be | |
4893 | * reasonably up-to-date and significantly shorter than | |
4894 | * dirty_expire_interval as that's what expires the record. | |
4895 | * Use the shorter of 1s and dirty_expire_interval / 8. | |
4896 | */ | |
4897 | unsigned long update_intv = | |
4898 | min_t(unsigned long, HZ, | |
4899 | msecs_to_jiffies(dirty_expire_interval * 10) / 8); | |
4900 | ||
4901 | if (time_before64(frn->at, now - update_intv)) | |
4902 | frn->at = now; | |
4903 | } else if (oldest >= 0) { | |
4904 | /* replace the oldest free one */ | |
4905 | frn = &memcg->cgwb_frn[oldest]; | |
4906 | frn->bdi_id = wb->bdi->id; | |
4907 | frn->memcg_id = wb->memcg_css->id; | |
4908 | frn->at = now; | |
4909 | } | |
4910 | } | |
4911 | ||
4912 | /* issue foreign writeback flushes for recorded foreign dirtying events */ | |
4913 | void mem_cgroup_flush_foreign(struct bdi_writeback *wb) | |
4914 | { | |
4915 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4916 | unsigned long intv = msecs_to_jiffies(dirty_expire_interval * 10); | |
4917 | u64 now = jiffies_64; | |
4918 | int i; | |
4919 | ||
4920 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) { | |
4921 | struct memcg_cgwb_frn *frn = &memcg->cgwb_frn[i]; | |
4922 | ||
4923 | /* | |
4924 | * If the record is older than dirty_expire_interval, | |
4925 | * writeback on it has already started. No need to kick it | |
4926 | * off again. Also, don't start a new one if there's | |
4927 | * already one in flight. | |
4928 | */ | |
4929 | if (time_after64(frn->at, now - intv) && | |
4930 | atomic_read(&frn->done.cnt) == 1) { | |
4931 | frn->at = 0; | |
3a8e9ac8 | 4932 | trace_flush_foreign(wb, frn->bdi_id, frn->memcg_id); |
7490a2d2 | 4933 | cgroup_writeback_by_id(frn->bdi_id, frn->memcg_id, |
97b27821 TH |
4934 | WB_REASON_FOREIGN_FLUSH, |
4935 | &frn->done); | |
4936 | } | |
4937 | } | |
4938 | } | |
4939 | ||
841710aa TH |
4940 | #else /* CONFIG_CGROUP_WRITEBACK */ |
4941 | ||
4942 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) | |
4943 | { | |
4944 | return 0; | |
4945 | } | |
4946 | ||
4947 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
4948 | { | |
4949 | } | |
4950 | ||
2529bb3a TH |
4951 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
4952 | { | |
4953 | } | |
4954 | ||
52ebea74 TH |
4955 | #endif /* CONFIG_CGROUP_WRITEBACK */ |
4956 | ||
3bc942f3 TH |
4957 | /* |
4958 | * DO NOT USE IN NEW FILES. | |
4959 | * | |
4960 | * "cgroup.event_control" implementation. | |
4961 | * | |
4962 | * This is way over-engineered. It tries to support fully configurable | |
4963 | * events for each user. Such level of flexibility is completely | |
4964 | * unnecessary especially in the light of the planned unified hierarchy. | |
4965 | * | |
4966 | * Please deprecate this and replace with something simpler if at all | |
4967 | * possible. | |
4968 | */ | |
4969 | ||
79bd9814 TH |
4970 | /* |
4971 | * Unregister event and free resources. | |
4972 | * | |
4973 | * Gets called from workqueue. | |
4974 | */ | |
3bc942f3 | 4975 | static void memcg_event_remove(struct work_struct *work) |
79bd9814 | 4976 | { |
3bc942f3 TH |
4977 | struct mem_cgroup_event *event = |
4978 | container_of(work, struct mem_cgroup_event, remove); | |
59b6f873 | 4979 | struct mem_cgroup *memcg = event->memcg; |
79bd9814 TH |
4980 | |
4981 | remove_wait_queue(event->wqh, &event->wait); | |
4982 | ||
59b6f873 | 4983 | event->unregister_event(memcg, event->eventfd); |
79bd9814 TH |
4984 | |
4985 | /* Notify userspace the event is going away. */ | |
3652117f | 4986 | eventfd_signal(event->eventfd); |
79bd9814 TH |
4987 | |
4988 | eventfd_ctx_put(event->eventfd); | |
4989 | kfree(event); | |
59b6f873 | 4990 | css_put(&memcg->css); |
79bd9814 TH |
4991 | } |
4992 | ||
4993 | /* | |
a9a08845 | 4994 | * Gets called on EPOLLHUP on eventfd when user closes it. |
79bd9814 TH |
4995 | * |
4996 | * Called with wqh->lock held and interrupts disabled. | |
4997 | */ | |
ac6424b9 | 4998 | static int memcg_event_wake(wait_queue_entry_t *wait, unsigned mode, |
3bc942f3 | 4999 | int sync, void *key) |
79bd9814 | 5000 | { |
3bc942f3 TH |
5001 | struct mem_cgroup_event *event = |
5002 | container_of(wait, struct mem_cgroup_event, wait); | |
59b6f873 | 5003 | struct mem_cgroup *memcg = event->memcg; |
3ad6f93e | 5004 | __poll_t flags = key_to_poll(key); |
79bd9814 | 5005 | |
a9a08845 | 5006 | if (flags & EPOLLHUP) { |
79bd9814 TH |
5007 | /* |
5008 | * If the event has been detached at cgroup removal, we | |
5009 | * can simply return knowing the other side will cleanup | |
5010 | * for us. | |
5011 | * | |
5012 | * We can't race against event freeing since the other | |
5013 | * side will require wqh->lock via remove_wait_queue(), | |
5014 | * which we hold. | |
5015 | */ | |
fba94807 | 5016 | spin_lock(&memcg->event_list_lock); |
79bd9814 TH |
5017 | if (!list_empty(&event->list)) { |
5018 | list_del_init(&event->list); | |
5019 | /* | |
5020 | * We are in atomic context, but cgroup_event_remove() | |
5021 | * may sleep, so we have to call it in workqueue. | |
5022 | */ | |
5023 | schedule_work(&event->remove); | |
5024 | } | |
fba94807 | 5025 | spin_unlock(&memcg->event_list_lock); |
79bd9814 TH |
5026 | } |
5027 | ||
5028 | return 0; | |
5029 | } | |
5030 | ||
3bc942f3 | 5031 | static void memcg_event_ptable_queue_proc(struct file *file, |
79bd9814 TH |
5032 | wait_queue_head_t *wqh, poll_table *pt) |
5033 | { | |
3bc942f3 TH |
5034 | struct mem_cgroup_event *event = |
5035 | container_of(pt, struct mem_cgroup_event, pt); | |
79bd9814 TH |
5036 | |
5037 | event->wqh = wqh; | |
5038 | add_wait_queue(wqh, &event->wait); | |
5039 | } | |
5040 | ||
5041 | /* | |
3bc942f3 TH |
5042 | * DO NOT USE IN NEW FILES. |
5043 | * | |
79bd9814 TH |
5044 | * Parse input and register new cgroup event handler. |
5045 | * | |
5046 | * Input must be in format '<event_fd> <control_fd> <args>'. | |
5047 | * Interpretation of args is defined by control file implementation. | |
5048 | */ | |
451af504 TH |
5049 | static ssize_t memcg_write_event_control(struct kernfs_open_file *of, |
5050 | char *buf, size_t nbytes, loff_t off) | |
79bd9814 | 5051 | { |
451af504 | 5052 | struct cgroup_subsys_state *css = of_css(of); |
fba94807 | 5053 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 5054 | struct mem_cgroup_event *event; |
79bd9814 TH |
5055 | struct cgroup_subsys_state *cfile_css; |
5056 | unsigned int efd, cfd; | |
5057 | struct fd efile; | |
5058 | struct fd cfile; | |
4a7ba45b | 5059 | struct dentry *cdentry; |
fba94807 | 5060 | const char *name; |
79bd9814 TH |
5061 | char *endp; |
5062 | int ret; | |
5063 | ||
2343e88d SAS |
5064 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) |
5065 | return -EOPNOTSUPP; | |
5066 | ||
451af504 TH |
5067 | buf = strstrip(buf); |
5068 | ||
5069 | efd = simple_strtoul(buf, &endp, 10); | |
79bd9814 TH |
5070 | if (*endp != ' ') |
5071 | return -EINVAL; | |
451af504 | 5072 | buf = endp + 1; |
79bd9814 | 5073 | |
451af504 | 5074 | cfd = simple_strtoul(buf, &endp, 10); |
79bd9814 TH |
5075 | if ((*endp != ' ') && (*endp != '\0')) |
5076 | return -EINVAL; | |
451af504 | 5077 | buf = endp + 1; |
79bd9814 TH |
5078 | |
5079 | event = kzalloc(sizeof(*event), GFP_KERNEL); | |
5080 | if (!event) | |
5081 | return -ENOMEM; | |
5082 | ||
59b6f873 | 5083 | event->memcg = memcg; |
79bd9814 | 5084 | INIT_LIST_HEAD(&event->list); |
3bc942f3 TH |
5085 | init_poll_funcptr(&event->pt, memcg_event_ptable_queue_proc); |
5086 | init_waitqueue_func_entry(&event->wait, memcg_event_wake); | |
5087 | INIT_WORK(&event->remove, memcg_event_remove); | |
79bd9814 TH |
5088 | |
5089 | efile = fdget(efd); | |
5090 | if (!efile.file) { | |
5091 | ret = -EBADF; | |
5092 | goto out_kfree; | |
5093 | } | |
5094 | ||
5095 | event->eventfd = eventfd_ctx_fileget(efile.file); | |
5096 | if (IS_ERR(event->eventfd)) { | |
5097 | ret = PTR_ERR(event->eventfd); | |
5098 | goto out_put_efile; | |
5099 | } | |
5100 | ||
5101 | cfile = fdget(cfd); | |
5102 | if (!cfile.file) { | |
5103 | ret = -EBADF; | |
5104 | goto out_put_eventfd; | |
5105 | } | |
5106 | ||
5107 | /* the process need read permission on control file */ | |
5108 | /* AV: shouldn't we check that it's been opened for read instead? */ | |
02f92b38 | 5109 | ret = file_permission(cfile.file, MAY_READ); |
79bd9814 TH |
5110 | if (ret < 0) |
5111 | goto out_put_cfile; | |
5112 | ||
4a7ba45b TH |
5113 | /* |
5114 | * The control file must be a regular cgroup1 file. As a regular cgroup | |
5115 | * file can't be renamed, it's safe to access its name afterwards. | |
5116 | */ | |
5117 | cdentry = cfile.file->f_path.dentry; | |
5118 | if (cdentry->d_sb->s_type != &cgroup_fs_type || !d_is_reg(cdentry)) { | |
5119 | ret = -EINVAL; | |
5120 | goto out_put_cfile; | |
5121 | } | |
5122 | ||
fba94807 TH |
5123 | /* |
5124 | * Determine the event callbacks and set them in @event. This used | |
5125 | * to be done via struct cftype but cgroup core no longer knows | |
5126 | * about these events. The following is crude but the whole thing | |
5127 | * is for compatibility anyway. | |
3bc942f3 TH |
5128 | * |
5129 | * DO NOT ADD NEW FILES. | |
fba94807 | 5130 | */ |
4a7ba45b | 5131 | name = cdentry->d_name.name; |
fba94807 TH |
5132 | |
5133 | if (!strcmp(name, "memory.usage_in_bytes")) { | |
5134 | event->register_event = mem_cgroup_usage_register_event; | |
5135 | event->unregister_event = mem_cgroup_usage_unregister_event; | |
5136 | } else if (!strcmp(name, "memory.oom_control")) { | |
5137 | event->register_event = mem_cgroup_oom_register_event; | |
5138 | event->unregister_event = mem_cgroup_oom_unregister_event; | |
5139 | } else if (!strcmp(name, "memory.pressure_level")) { | |
5140 | event->register_event = vmpressure_register_event; | |
5141 | event->unregister_event = vmpressure_unregister_event; | |
5142 | } else if (!strcmp(name, "memory.memsw.usage_in_bytes")) { | |
347c4a87 TH |
5143 | event->register_event = memsw_cgroup_usage_register_event; |
5144 | event->unregister_event = memsw_cgroup_usage_unregister_event; | |
fba94807 TH |
5145 | } else { |
5146 | ret = -EINVAL; | |
5147 | goto out_put_cfile; | |
5148 | } | |
5149 | ||
79bd9814 | 5150 | /* |
b5557c4c TH |
5151 | * Verify @cfile should belong to @css. Also, remaining events are |
5152 | * automatically removed on cgroup destruction but the removal is | |
5153 | * asynchronous, so take an extra ref on @css. | |
79bd9814 | 5154 | */ |
4a7ba45b | 5155 | cfile_css = css_tryget_online_from_dir(cdentry->d_parent, |
ec903c0c | 5156 | &memory_cgrp_subsys); |
79bd9814 | 5157 | ret = -EINVAL; |
5a17f543 | 5158 | if (IS_ERR(cfile_css)) |
79bd9814 | 5159 | goto out_put_cfile; |
5a17f543 TH |
5160 | if (cfile_css != css) { |
5161 | css_put(cfile_css); | |
79bd9814 | 5162 | goto out_put_cfile; |
5a17f543 | 5163 | } |
79bd9814 | 5164 | |
451af504 | 5165 | ret = event->register_event(memcg, event->eventfd, buf); |
79bd9814 TH |
5166 | if (ret) |
5167 | goto out_put_css; | |
5168 | ||
9965ed17 | 5169 | vfs_poll(efile.file, &event->pt); |
79bd9814 | 5170 | |
4ba9515d | 5171 | spin_lock_irq(&memcg->event_list_lock); |
fba94807 | 5172 | list_add(&event->list, &memcg->event_list); |
4ba9515d | 5173 | spin_unlock_irq(&memcg->event_list_lock); |
79bd9814 TH |
5174 | |
5175 | fdput(cfile); | |
5176 | fdput(efile); | |
5177 | ||
451af504 | 5178 | return nbytes; |
79bd9814 TH |
5179 | |
5180 | out_put_css: | |
b5557c4c | 5181 | css_put(css); |
79bd9814 TH |
5182 | out_put_cfile: |
5183 | fdput(cfile); | |
5184 | out_put_eventfd: | |
5185 | eventfd_ctx_put(event->eventfd); | |
5186 | out_put_efile: | |
5187 | fdput(efile); | |
5188 | out_kfree: | |
5189 | kfree(event); | |
5190 | ||
5191 | return ret; | |
5192 | } | |
5193 | ||
bc3dcb85 | 5194 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_SLUB_DEBUG) |
c29b5b3d MS |
5195 | static int mem_cgroup_slab_show(struct seq_file *m, void *p) |
5196 | { | |
5197 | /* | |
5198 | * Deprecated. | |
df4ae285 | 5199 | * Please, take a look at tools/cgroup/memcg_slabinfo.py . |
c29b5b3d MS |
5200 | */ |
5201 | return 0; | |
5202 | } | |
5203 | #endif | |
5204 | ||
dddb44ff YA |
5205 | static int memory_stat_show(struct seq_file *m, void *v); |
5206 | ||
241994ed | 5207 | static struct cftype mem_cgroup_legacy_files[] = { |
8cdea7c0 | 5208 | { |
0eea1030 | 5209 | .name = "usage_in_bytes", |
8c7c6e34 | 5210 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
791badbd | 5211 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 5212 | }, |
c84872e1 PE |
5213 | { |
5214 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 5215 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
6770c64e | 5216 | .write = mem_cgroup_reset, |
791badbd | 5217 | .read_u64 = mem_cgroup_read_u64, |
c84872e1 | 5218 | }, |
8cdea7c0 | 5219 | { |
0eea1030 | 5220 | .name = "limit_in_bytes", |
8c7c6e34 | 5221 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
451af504 | 5222 | .write = mem_cgroup_write, |
791badbd | 5223 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 5224 | }, |
296c81d8 BS |
5225 | { |
5226 | .name = "soft_limit_in_bytes", | |
5227 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
451af504 | 5228 | .write = mem_cgroup_write, |
791badbd | 5229 | .read_u64 = mem_cgroup_read_u64, |
296c81d8 | 5230 | }, |
8cdea7c0 BS |
5231 | { |
5232 | .name = "failcnt", | |
8c7c6e34 | 5233 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
6770c64e | 5234 | .write = mem_cgroup_reset, |
791badbd | 5235 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 5236 | }, |
d2ceb9b7 KH |
5237 | { |
5238 | .name = "stat", | |
dddb44ff | 5239 | .seq_show = memory_stat_show, |
d2ceb9b7 | 5240 | }, |
c1e862c1 KH |
5241 | { |
5242 | .name = "force_empty", | |
6770c64e | 5243 | .write = mem_cgroup_force_empty_write, |
c1e862c1 | 5244 | }, |
18f59ea7 BS |
5245 | { |
5246 | .name = "use_hierarchy", | |
5247 | .write_u64 = mem_cgroup_hierarchy_write, | |
5248 | .read_u64 = mem_cgroup_hierarchy_read, | |
5249 | }, | |
79bd9814 | 5250 | { |
3bc942f3 | 5251 | .name = "cgroup.event_control", /* XXX: for compat */ |
451af504 | 5252 | .write = memcg_write_event_control, |
7dbdb199 | 5253 | .flags = CFTYPE_NO_PREFIX | CFTYPE_WORLD_WRITABLE, |
79bd9814 | 5254 | }, |
a7885eb8 KM |
5255 | { |
5256 | .name = "swappiness", | |
5257 | .read_u64 = mem_cgroup_swappiness_read, | |
5258 | .write_u64 = mem_cgroup_swappiness_write, | |
5259 | }, | |
7dc74be0 DN |
5260 | { |
5261 | .name = "move_charge_at_immigrate", | |
5262 | .read_u64 = mem_cgroup_move_charge_read, | |
5263 | .write_u64 = mem_cgroup_move_charge_write, | |
5264 | }, | |
9490ff27 KH |
5265 | { |
5266 | .name = "oom_control", | |
2da8ca82 | 5267 | .seq_show = mem_cgroup_oom_control_read, |
3c11ecf4 | 5268 | .write_u64 = mem_cgroup_oom_control_write, |
9490ff27 | 5269 | }, |
70ddf637 AV |
5270 | { |
5271 | .name = "pressure_level", | |
6b0ba2ab | 5272 | .seq_show = mem_cgroup_dummy_seq_show, |
70ddf637 | 5273 | }, |
406eb0c9 YH |
5274 | #ifdef CONFIG_NUMA |
5275 | { | |
5276 | .name = "numa_stat", | |
2da8ca82 | 5277 | .seq_show = memcg_numa_stat_show, |
406eb0c9 YH |
5278 | }, |
5279 | #endif | |
4597648f MH |
5280 | { |
5281 | .name = "kmem.limit_in_bytes", | |
5282 | .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT), | |
5283 | .write = mem_cgroup_write, | |
5284 | .read_u64 = mem_cgroup_read_u64, | |
5285 | }, | |
510fc4e1 GC |
5286 | { |
5287 | .name = "kmem.usage_in_bytes", | |
5288 | .private = MEMFILE_PRIVATE(_KMEM, RES_USAGE), | |
791badbd | 5289 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
5290 | }, |
5291 | { | |
5292 | .name = "kmem.failcnt", | |
5293 | .private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT), | |
6770c64e | 5294 | .write = mem_cgroup_reset, |
791badbd | 5295 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
5296 | }, |
5297 | { | |
5298 | .name = "kmem.max_usage_in_bytes", | |
5299 | .private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE), | |
6770c64e | 5300 | .write = mem_cgroup_reset, |
791badbd | 5301 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 | 5302 | }, |
bc3dcb85 | 5303 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_SLUB_DEBUG) |
749c5415 GC |
5304 | { |
5305 | .name = "kmem.slabinfo", | |
c29b5b3d | 5306 | .seq_show = mem_cgroup_slab_show, |
749c5415 GC |
5307 | }, |
5308 | #endif | |
d55f90bf VD |
5309 | { |
5310 | .name = "kmem.tcp.limit_in_bytes", | |
5311 | .private = MEMFILE_PRIVATE(_TCP, RES_LIMIT), | |
5312 | .write = mem_cgroup_write, | |
5313 | .read_u64 = mem_cgroup_read_u64, | |
5314 | }, | |
5315 | { | |
5316 | .name = "kmem.tcp.usage_in_bytes", | |
5317 | .private = MEMFILE_PRIVATE(_TCP, RES_USAGE), | |
5318 | .read_u64 = mem_cgroup_read_u64, | |
5319 | }, | |
5320 | { | |
5321 | .name = "kmem.tcp.failcnt", | |
5322 | .private = MEMFILE_PRIVATE(_TCP, RES_FAILCNT), | |
5323 | .write = mem_cgroup_reset, | |
5324 | .read_u64 = mem_cgroup_read_u64, | |
5325 | }, | |
5326 | { | |
5327 | .name = "kmem.tcp.max_usage_in_bytes", | |
5328 | .private = MEMFILE_PRIVATE(_TCP, RES_MAX_USAGE), | |
5329 | .write = mem_cgroup_reset, | |
5330 | .read_u64 = mem_cgroup_read_u64, | |
5331 | }, | |
6bc10349 | 5332 | { }, /* terminate */ |
af36f906 | 5333 | }; |
8c7c6e34 | 5334 | |
73f576c0 JW |
5335 | /* |
5336 | * Private memory cgroup IDR | |
5337 | * | |
5338 | * Swap-out records and page cache shadow entries need to store memcg | |
5339 | * references in constrained space, so we maintain an ID space that is | |
5340 | * limited to 16 bit (MEM_CGROUP_ID_MAX), limiting the total number of | |
5341 | * memory-controlled cgroups to 64k. | |
5342 | * | |
b8f2935f | 5343 | * However, there usually are many references to the offline CSS after |
73f576c0 JW |
5344 | * the cgroup has been destroyed, such as page cache or reclaimable |
5345 | * slab objects, that don't need to hang on to the ID. We want to keep | |
5346 | * those dead CSS from occupying IDs, or we might quickly exhaust the | |
5347 | * relatively small ID space and prevent the creation of new cgroups | |
5348 | * even when there are much fewer than 64k cgroups - possibly none. | |
5349 | * | |
5350 | * Maintain a private 16-bit ID space for memcg, and allow the ID to | |
5351 | * be freed and recycled when it's no longer needed, which is usually | |
5352 | * when the CSS is offlined. | |
5353 | * | |
5354 | * The only exception to that are records of swapped out tmpfs/shmem | |
5355 | * pages that need to be attributed to live ancestors on swapin. But | |
5356 | * those references are manageable from userspace. | |
5357 | */ | |
5358 | ||
60b1e24c | 5359 | #define MEM_CGROUP_ID_MAX ((1UL << MEM_CGROUP_ID_SHIFT) - 1) |
73f576c0 JW |
5360 | static DEFINE_IDR(mem_cgroup_idr); |
5361 | ||
7e97de0b KT |
5362 | static void mem_cgroup_id_remove(struct mem_cgroup *memcg) |
5363 | { | |
5364 | if (memcg->id.id > 0) { | |
5365 | idr_remove(&mem_cgroup_idr, memcg->id.id); | |
5366 | memcg->id.id = 0; | |
5367 | } | |
5368 | } | |
5369 | ||
c1514c0a VF |
5370 | static void __maybe_unused mem_cgroup_id_get_many(struct mem_cgroup *memcg, |
5371 | unsigned int n) | |
73f576c0 | 5372 | { |
1c2d479a | 5373 | refcount_add(n, &memcg->id.ref); |
73f576c0 JW |
5374 | } |
5375 | ||
615d66c3 | 5376 | static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n) |
73f576c0 | 5377 | { |
1c2d479a | 5378 | if (refcount_sub_and_test(n, &memcg->id.ref)) { |
7e97de0b | 5379 | mem_cgroup_id_remove(memcg); |
73f576c0 JW |
5380 | |
5381 | /* Memcg ID pins CSS */ | |
5382 | css_put(&memcg->css); | |
5383 | } | |
5384 | } | |
5385 | ||
615d66c3 VD |
5386 | static inline void mem_cgroup_id_put(struct mem_cgroup *memcg) |
5387 | { | |
5388 | mem_cgroup_id_put_many(memcg, 1); | |
5389 | } | |
5390 | ||
73f576c0 JW |
5391 | /** |
5392 | * mem_cgroup_from_id - look up a memcg from a memcg id | |
5393 | * @id: the memcg id to look up | |
5394 | * | |
5395 | * Caller must hold rcu_read_lock(). | |
5396 | */ | |
5397 | struct mem_cgroup *mem_cgroup_from_id(unsigned short id) | |
5398 | { | |
5399 | WARN_ON_ONCE(!rcu_read_lock_held()); | |
5400 | return idr_find(&mem_cgroup_idr, id); | |
5401 | } | |
5402 | ||
c15187a4 RG |
5403 | #ifdef CONFIG_SHRINKER_DEBUG |
5404 | struct mem_cgroup *mem_cgroup_get_from_ino(unsigned long ino) | |
5405 | { | |
5406 | struct cgroup *cgrp; | |
5407 | struct cgroup_subsys_state *css; | |
5408 | struct mem_cgroup *memcg; | |
5409 | ||
5410 | cgrp = cgroup_get_from_id(ino); | |
fa7e439c | 5411 | if (IS_ERR(cgrp)) |
c0f2df49 | 5412 | return ERR_CAST(cgrp); |
c15187a4 RG |
5413 | |
5414 | css = cgroup_get_e_css(cgrp, &memory_cgrp_subsys); | |
5415 | if (css) | |
5416 | memcg = container_of(css, struct mem_cgroup, css); | |
5417 | else | |
5418 | memcg = ERR_PTR(-ENOENT); | |
5419 | ||
5420 | cgroup_put(cgrp); | |
5421 | ||
5422 | return memcg; | |
5423 | } | |
5424 | #endif | |
5425 | ||
ef8f2327 | 5426 | static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) |
6d12e2d8 KH |
5427 | { |
5428 | struct mem_cgroup_per_node *pn; | |
8c9bb398 WY |
5429 | |
5430 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, node); | |
6d12e2d8 KH |
5431 | if (!pn) |
5432 | return 1; | |
1ecaab2b | 5433 | |
7e1c0d6f SB |
5434 | pn->lruvec_stats_percpu = alloc_percpu_gfp(struct lruvec_stats_percpu, |
5435 | GFP_KERNEL_ACCOUNT); | |
5436 | if (!pn->lruvec_stats_percpu) { | |
00f3ca2c JW |
5437 | kfree(pn); |
5438 | return 1; | |
5439 | } | |
5440 | ||
ef8f2327 | 5441 | lruvec_init(&pn->lruvec); |
ef8f2327 MG |
5442 | pn->memcg = memcg; |
5443 | ||
54f72fe0 | 5444 | memcg->nodeinfo[node] = pn; |
6d12e2d8 KH |
5445 | return 0; |
5446 | } | |
5447 | ||
ef8f2327 | 5448 | static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) |
1ecaab2b | 5449 | { |
00f3ca2c JW |
5450 | struct mem_cgroup_per_node *pn = memcg->nodeinfo[node]; |
5451 | ||
4eaf431f MH |
5452 | if (!pn) |
5453 | return; | |
5454 | ||
7e1c0d6f | 5455 | free_percpu(pn->lruvec_stats_percpu); |
00f3ca2c | 5456 | kfree(pn); |
1ecaab2b KH |
5457 | } |
5458 | ||
40e952f9 | 5459 | static void __mem_cgroup_free(struct mem_cgroup *memcg) |
59927fb9 | 5460 | { |
c8b2a36f | 5461 | int node; |
59927fb9 | 5462 | |
675d6c9b RG |
5463 | if (memcg->orig_objcg) |
5464 | obj_cgroup_put(memcg->orig_objcg); | |
5465 | ||
c8b2a36f | 5466 | for_each_node(node) |
ef8f2327 | 5467 | free_mem_cgroup_per_node_info(memcg, node); |
410f8e82 | 5468 | kfree(memcg->vmstats); |
871789d4 | 5469 | free_percpu(memcg->vmstats_percpu); |
8ff69e2c | 5470 | kfree(memcg); |
59927fb9 | 5471 | } |
3afe36b1 | 5472 | |
40e952f9 TE |
5473 | static void mem_cgroup_free(struct mem_cgroup *memcg) |
5474 | { | |
ec1c86b2 | 5475 | lru_gen_exit_memcg(memcg); |
40e952f9 TE |
5476 | memcg_wb_domain_exit(memcg); |
5477 | __mem_cgroup_free(memcg); | |
5478 | } | |
5479 | ||
0b8f73e1 | 5480 | static struct mem_cgroup *mem_cgroup_alloc(void) |
8cdea7c0 | 5481 | { |
d142e3e6 | 5482 | struct mem_cgroup *memcg; |
6d12e2d8 | 5483 | int node; |
97b27821 | 5484 | int __maybe_unused i; |
11d67612 | 5485 | long error = -ENOMEM; |
8cdea7c0 | 5486 | |
06b2c3b0 | 5487 | memcg = kzalloc(struct_size(memcg, nodeinfo, nr_node_ids), GFP_KERNEL); |
c0ff4b85 | 5488 | if (!memcg) |
11d67612 | 5489 | return ERR_PTR(error); |
0b8f73e1 | 5490 | |
73f576c0 | 5491 | memcg->id.id = idr_alloc(&mem_cgroup_idr, NULL, |
be740503 | 5492 | 1, MEM_CGROUP_ID_MAX + 1, GFP_KERNEL); |
11d67612 YS |
5493 | if (memcg->id.id < 0) { |
5494 | error = memcg->id.id; | |
73f576c0 | 5495 | goto fail; |
11d67612 | 5496 | } |
73f576c0 | 5497 | |
410f8e82 SB |
5498 | memcg->vmstats = kzalloc(sizeof(struct memcg_vmstats), GFP_KERNEL); |
5499 | if (!memcg->vmstats) | |
5500 | goto fail; | |
5501 | ||
3e38e0aa RG |
5502 | memcg->vmstats_percpu = alloc_percpu_gfp(struct memcg_vmstats_percpu, |
5503 | GFP_KERNEL_ACCOUNT); | |
871789d4 | 5504 | if (!memcg->vmstats_percpu) |
0b8f73e1 | 5505 | goto fail; |
78fb7466 | 5506 | |
3ed28fa1 | 5507 | for_each_node(node) |
ef8f2327 | 5508 | if (alloc_mem_cgroup_per_node_info(memcg, node)) |
0b8f73e1 | 5509 | goto fail; |
f64c3f54 | 5510 | |
0b8f73e1 JW |
5511 | if (memcg_wb_domain_init(memcg, GFP_KERNEL)) |
5512 | goto fail; | |
28dbc4b6 | 5513 | |
f7e1cb6e | 5514 | INIT_WORK(&memcg->high_work, high_work_func); |
d142e3e6 | 5515 | INIT_LIST_HEAD(&memcg->oom_notify); |
d142e3e6 GC |
5516 | mutex_init(&memcg->thresholds_lock); |
5517 | spin_lock_init(&memcg->move_lock); | |
70ddf637 | 5518 | vmpressure_init(&memcg->vmpressure); |
fba94807 TH |
5519 | INIT_LIST_HEAD(&memcg->event_list); |
5520 | spin_lock_init(&memcg->event_list_lock); | |
d886f4e4 | 5521 | memcg->socket_pressure = jiffies; |
84c07d11 | 5522 | #ifdef CONFIG_MEMCG_KMEM |
900a38f0 | 5523 | memcg->kmemcg_id = -1; |
bf4f0599 | 5524 | INIT_LIST_HEAD(&memcg->objcg_list); |
900a38f0 | 5525 | #endif |
52ebea74 TH |
5526 | #ifdef CONFIG_CGROUP_WRITEBACK |
5527 | INIT_LIST_HEAD(&memcg->cgwb_list); | |
97b27821 TH |
5528 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) |
5529 | memcg->cgwb_frn[i].done = | |
5530 | __WB_COMPLETION_INIT(&memcg_cgwb_frn_waitq); | |
87eaceb3 YS |
5531 | #endif |
5532 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
5533 | spin_lock_init(&memcg->deferred_split_queue.split_queue_lock); | |
5534 | INIT_LIST_HEAD(&memcg->deferred_split_queue.split_queue); | |
5535 | memcg->deferred_split_queue.split_queue_len = 0; | |
52ebea74 | 5536 | #endif |
ec1c86b2 | 5537 | lru_gen_init_memcg(memcg); |
0b8f73e1 JW |
5538 | return memcg; |
5539 | fail: | |
7e97de0b | 5540 | mem_cgroup_id_remove(memcg); |
40e952f9 | 5541 | __mem_cgroup_free(memcg); |
11d67612 | 5542 | return ERR_PTR(error); |
d142e3e6 GC |
5543 | } |
5544 | ||
0b8f73e1 JW |
5545 | static struct cgroup_subsys_state * __ref |
5546 | mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
d142e3e6 | 5547 | { |
0b8f73e1 | 5548 | struct mem_cgroup *parent = mem_cgroup_from_css(parent_css); |
b87d8cef | 5549 | struct mem_cgroup *memcg, *old_memcg; |
d142e3e6 | 5550 | |
b87d8cef | 5551 | old_memcg = set_active_memcg(parent); |
0b8f73e1 | 5552 | memcg = mem_cgroup_alloc(); |
b87d8cef | 5553 | set_active_memcg(old_memcg); |
11d67612 YS |
5554 | if (IS_ERR(memcg)) |
5555 | return ERR_CAST(memcg); | |
d142e3e6 | 5556 | |
d1663a90 | 5557 | page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX); |
2178e20c | 5558 | WRITE_ONCE(memcg->soft_limit, PAGE_COUNTER_MAX); |
f4840ccf JW |
5559 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
5560 | memcg->zswap_max = PAGE_COUNTER_MAX; | |
501a06fe NP |
5561 | WRITE_ONCE(memcg->zswap_writeback, |
5562 | !parent || READ_ONCE(parent->zswap_writeback)); | |
f4840ccf | 5563 | #endif |
4b82ab4f | 5564 | page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX); |
0b8f73e1 | 5565 | if (parent) { |
82b3aa26 | 5566 | WRITE_ONCE(memcg->swappiness, mem_cgroup_swappiness(parent)); |
17c56de6 | 5567 | WRITE_ONCE(memcg->oom_kill_disable, READ_ONCE(parent->oom_kill_disable)); |
bef8620c | 5568 | |
3e32cb2e | 5569 | page_counter_init(&memcg->memory, &parent->memory); |
37e84351 | 5570 | page_counter_init(&memcg->swap, &parent->swap); |
3e32cb2e | 5571 | page_counter_init(&memcg->kmem, &parent->kmem); |
0db15298 | 5572 | page_counter_init(&memcg->tcpmem, &parent->tcpmem); |
18f59ea7 | 5573 | } else { |
8278f1c7 | 5574 | init_memcg_events(); |
bef8620c RG |
5575 | page_counter_init(&memcg->memory, NULL); |
5576 | page_counter_init(&memcg->swap, NULL); | |
5577 | page_counter_init(&memcg->kmem, NULL); | |
5578 | page_counter_init(&memcg->tcpmem, NULL); | |
d6441637 | 5579 | |
0b8f73e1 JW |
5580 | root_mem_cgroup = memcg; |
5581 | return &memcg->css; | |
5582 | } | |
5583 | ||
f7e1cb6e | 5584 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 5585 | static_branch_inc(&memcg_sockets_enabled_key); |
f7e1cb6e | 5586 | |
b6c1a8af YS |
5587 | #if defined(CONFIG_MEMCG_KMEM) |
5588 | if (!cgroup_memory_nobpf) | |
5589 | static_branch_inc(&memcg_bpf_enabled_key); | |
5590 | #endif | |
5591 | ||
0b8f73e1 | 5592 | return &memcg->css; |
0b8f73e1 JW |
5593 | } |
5594 | ||
73f576c0 | 5595 | static int mem_cgroup_css_online(struct cgroup_subsys_state *css) |
0b8f73e1 | 5596 | { |
58fa2a55 VD |
5597 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
5598 | ||
da0efe30 MS |
5599 | if (memcg_online_kmem(memcg)) |
5600 | goto remove_id; | |
5601 | ||
0a4465d3 | 5602 | /* |
e4262c4f | 5603 | * A memcg must be visible for expand_shrinker_info() |
0a4465d3 KT |
5604 | * by the time the maps are allocated. So, we allocate maps |
5605 | * here, when for_each_mem_cgroup() can't skip it. | |
5606 | */ | |
da0efe30 MS |
5607 | if (alloc_shrinker_info(memcg)) |
5608 | goto offline_kmem; | |
0a4465d3 | 5609 | |
aa48e47e SB |
5610 | if (unlikely(mem_cgroup_is_root(memcg))) |
5611 | queue_delayed_work(system_unbound_wq, &stats_flush_dwork, | |
396faf88 | 5612 | FLUSH_TIME); |
e4dde56c | 5613 | lru_gen_online_memcg(memcg); |
6f0df8e1 JW |
5614 | |
5615 | /* Online state pins memcg ID, memcg ID pins CSS */ | |
5616 | refcount_set(&memcg->id.ref, 1); | |
5617 | css_get(css); | |
5618 | ||
5619 | /* | |
5620 | * Ensure mem_cgroup_from_id() works once we're fully online. | |
5621 | * | |
5622 | * We could do this earlier and require callers to filter with | |
5623 | * css_tryget_online(). But right now there are no users that | |
5624 | * need earlier access, and the workingset code relies on the | |
5625 | * cgroup tree linkage (mem_cgroup_get_nr_swap_pages()). So | |
5626 | * publish it here at the end of onlining. This matches the | |
5627 | * regular ID destruction during offlining. | |
5628 | */ | |
5629 | idr_replace(&mem_cgroup_idr, memcg, memcg->id.id); | |
5630 | ||
2f7dd7a4 | 5631 | return 0; |
da0efe30 MS |
5632 | offline_kmem: |
5633 | memcg_offline_kmem(memcg); | |
5634 | remove_id: | |
5635 | mem_cgroup_id_remove(memcg); | |
5636 | return -ENOMEM; | |
8cdea7c0 BS |
5637 | } |
5638 | ||
eb95419b | 5639 | static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) |
df878fb0 | 5640 | { |
eb95419b | 5641 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 5642 | struct mem_cgroup_event *event, *tmp; |
79bd9814 TH |
5643 | |
5644 | /* | |
5645 | * Unregister events and notify userspace. | |
5646 | * Notify userspace about cgroup removing only after rmdir of cgroup | |
5647 | * directory to avoid race between userspace and kernelspace. | |
5648 | */ | |
4ba9515d | 5649 | spin_lock_irq(&memcg->event_list_lock); |
fba94807 | 5650 | list_for_each_entry_safe(event, tmp, &memcg->event_list, list) { |
79bd9814 TH |
5651 | list_del_init(&event->list); |
5652 | schedule_work(&event->remove); | |
5653 | } | |
4ba9515d | 5654 | spin_unlock_irq(&memcg->event_list_lock); |
ec64f515 | 5655 | |
bf8d5d52 | 5656 | page_counter_set_min(&memcg->memory, 0); |
23067153 | 5657 | page_counter_set_low(&memcg->memory, 0); |
63677c74 | 5658 | |
a65b0e76 DC |
5659 | zswap_memcg_offline_cleanup(memcg); |
5660 | ||
567e9ab2 | 5661 | memcg_offline_kmem(memcg); |
a178015c | 5662 | reparent_shrinker_deferred(memcg); |
52ebea74 | 5663 | wb_memcg_offline(memcg); |
e4dde56c | 5664 | lru_gen_offline_memcg(memcg); |
73f576c0 | 5665 | |
591edfb1 RG |
5666 | drain_all_stock(memcg); |
5667 | ||
73f576c0 | 5668 | mem_cgroup_id_put(memcg); |
df878fb0 KH |
5669 | } |
5670 | ||
6df38689 VD |
5671 | static void mem_cgroup_css_released(struct cgroup_subsys_state *css) |
5672 | { | |
5673 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5674 | ||
5675 | invalidate_reclaim_iterators(memcg); | |
e4dde56c | 5676 | lru_gen_release_memcg(memcg); |
6df38689 VD |
5677 | } |
5678 | ||
eb95419b | 5679 | static void mem_cgroup_css_free(struct cgroup_subsys_state *css) |
8cdea7c0 | 5680 | { |
eb95419b | 5681 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
97b27821 | 5682 | int __maybe_unused i; |
c268e994 | 5683 | |
97b27821 TH |
5684 | #ifdef CONFIG_CGROUP_WRITEBACK |
5685 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) | |
5686 | wb_wait_for_completion(&memcg->cgwb_frn[i].done); | |
5687 | #endif | |
f7e1cb6e | 5688 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 5689 | static_branch_dec(&memcg_sockets_enabled_key); |
127424c8 | 5690 | |
0db15298 | 5691 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_active) |
d55f90bf | 5692 | static_branch_dec(&memcg_sockets_enabled_key); |
3893e302 | 5693 | |
b6c1a8af YS |
5694 | #if defined(CONFIG_MEMCG_KMEM) |
5695 | if (!cgroup_memory_nobpf) | |
5696 | static_branch_dec(&memcg_bpf_enabled_key); | |
5697 | #endif | |
5698 | ||
0b8f73e1 JW |
5699 | vmpressure_cleanup(&memcg->vmpressure); |
5700 | cancel_work_sync(&memcg->high_work); | |
5701 | mem_cgroup_remove_from_trees(memcg); | |
e4262c4f | 5702 | free_shrinker_info(memcg); |
0b8f73e1 | 5703 | mem_cgroup_free(memcg); |
8cdea7c0 BS |
5704 | } |
5705 | ||
1ced953b TH |
5706 | /** |
5707 | * mem_cgroup_css_reset - reset the states of a mem_cgroup | |
5708 | * @css: the target css | |
5709 | * | |
5710 | * Reset the states of the mem_cgroup associated with @css. This is | |
5711 | * invoked when the userland requests disabling on the default hierarchy | |
5712 | * but the memcg is pinned through dependency. The memcg should stop | |
5713 | * applying policies and should revert to the vanilla state as it may be | |
5714 | * made visible again. | |
5715 | * | |
5716 | * The current implementation only resets the essential configurations. | |
5717 | * This needs to be expanded to cover all the visible parts. | |
5718 | */ | |
5719 | static void mem_cgroup_css_reset(struct cgroup_subsys_state *css) | |
5720 | { | |
5721 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5722 | ||
bbec2e15 RG |
5723 | page_counter_set_max(&memcg->memory, PAGE_COUNTER_MAX); |
5724 | page_counter_set_max(&memcg->swap, PAGE_COUNTER_MAX); | |
bbec2e15 RG |
5725 | page_counter_set_max(&memcg->kmem, PAGE_COUNTER_MAX); |
5726 | page_counter_set_max(&memcg->tcpmem, PAGE_COUNTER_MAX); | |
bf8d5d52 | 5727 | page_counter_set_min(&memcg->memory, 0); |
23067153 | 5728 | page_counter_set_low(&memcg->memory, 0); |
d1663a90 | 5729 | page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX); |
2178e20c | 5730 | WRITE_ONCE(memcg->soft_limit, PAGE_COUNTER_MAX); |
4b82ab4f | 5731 | page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX); |
2529bb3a | 5732 | memcg_wb_domain_size_changed(memcg); |
1ced953b TH |
5733 | } |
5734 | ||
2d146aa3 JW |
5735 | static void mem_cgroup_css_rstat_flush(struct cgroup_subsys_state *css, int cpu) |
5736 | { | |
5737 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5738 | struct mem_cgroup *parent = parent_mem_cgroup(memcg); | |
5739 | struct memcg_vmstats_percpu *statc; | |
f82e6bf9 | 5740 | long delta, delta_cpu, v; |
7e1c0d6f | 5741 | int i, nid; |
2d146aa3 JW |
5742 | |
5743 | statc = per_cpu_ptr(memcg->vmstats_percpu, cpu); | |
5744 | ||
5745 | for (i = 0; i < MEMCG_NR_STAT; i++) { | |
5746 | /* | |
5747 | * Collect the aggregated propagation counts of groups | |
5748 | * below us. We're in a per-cpu loop here and this is | |
5749 | * a global counter, so the first cycle will get them. | |
5750 | */ | |
410f8e82 | 5751 | delta = memcg->vmstats->state_pending[i]; |
2d146aa3 | 5752 | if (delta) |
410f8e82 | 5753 | memcg->vmstats->state_pending[i] = 0; |
2d146aa3 JW |
5754 | |
5755 | /* Add CPU changes on this level since the last flush */ | |
f82e6bf9 | 5756 | delta_cpu = 0; |
2d146aa3 JW |
5757 | v = READ_ONCE(statc->state[i]); |
5758 | if (v != statc->state_prev[i]) { | |
f82e6bf9 YA |
5759 | delta_cpu = v - statc->state_prev[i]; |
5760 | delta += delta_cpu; | |
2d146aa3 JW |
5761 | statc->state_prev[i] = v; |
5762 | } | |
5763 | ||
2d146aa3 | 5764 | /* Aggregate counts on this level and propagate upwards */ |
f82e6bf9 YA |
5765 | if (delta_cpu) |
5766 | memcg->vmstats->state_local[i] += delta_cpu; | |
5767 | ||
5768 | if (delta) { | |
5769 | memcg->vmstats->state[i] += delta; | |
5770 | if (parent) | |
5771 | parent->vmstats->state_pending[i] += delta; | |
5772 | } | |
2d146aa3 JW |
5773 | } |
5774 | ||
8278f1c7 | 5775 | for (i = 0; i < NR_MEMCG_EVENTS; i++) { |
410f8e82 | 5776 | delta = memcg->vmstats->events_pending[i]; |
2d146aa3 | 5777 | if (delta) |
410f8e82 | 5778 | memcg->vmstats->events_pending[i] = 0; |
2d146aa3 | 5779 | |
f82e6bf9 | 5780 | delta_cpu = 0; |
2d146aa3 JW |
5781 | v = READ_ONCE(statc->events[i]); |
5782 | if (v != statc->events_prev[i]) { | |
f82e6bf9 YA |
5783 | delta_cpu = v - statc->events_prev[i]; |
5784 | delta += delta_cpu; | |
2d146aa3 JW |
5785 | statc->events_prev[i] = v; |
5786 | } | |
5787 | ||
f82e6bf9 YA |
5788 | if (delta_cpu) |
5789 | memcg->vmstats->events_local[i] += delta_cpu; | |
2d146aa3 | 5790 | |
f82e6bf9 YA |
5791 | if (delta) { |
5792 | memcg->vmstats->events[i] += delta; | |
5793 | if (parent) | |
5794 | parent->vmstats->events_pending[i] += delta; | |
5795 | } | |
2d146aa3 | 5796 | } |
7e1c0d6f SB |
5797 | |
5798 | for_each_node_state(nid, N_MEMORY) { | |
5799 | struct mem_cgroup_per_node *pn = memcg->nodeinfo[nid]; | |
5800 | struct mem_cgroup_per_node *ppn = NULL; | |
5801 | struct lruvec_stats_percpu *lstatc; | |
5802 | ||
5803 | if (parent) | |
5804 | ppn = parent->nodeinfo[nid]; | |
5805 | ||
5806 | lstatc = per_cpu_ptr(pn->lruvec_stats_percpu, cpu); | |
5807 | ||
5808 | for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { | |
5809 | delta = pn->lruvec_stats.state_pending[i]; | |
5810 | if (delta) | |
5811 | pn->lruvec_stats.state_pending[i] = 0; | |
5812 | ||
f82e6bf9 | 5813 | delta_cpu = 0; |
7e1c0d6f SB |
5814 | v = READ_ONCE(lstatc->state[i]); |
5815 | if (v != lstatc->state_prev[i]) { | |
f82e6bf9 YA |
5816 | delta_cpu = v - lstatc->state_prev[i]; |
5817 | delta += delta_cpu; | |
7e1c0d6f SB |
5818 | lstatc->state_prev[i] = v; |
5819 | } | |
5820 | ||
f82e6bf9 YA |
5821 | if (delta_cpu) |
5822 | pn->lruvec_stats.state_local[i] += delta_cpu; | |
7e1c0d6f | 5823 | |
f82e6bf9 YA |
5824 | if (delta) { |
5825 | pn->lruvec_stats.state[i] += delta; | |
5826 | if (ppn) | |
5827 | ppn->lruvec_stats.state_pending[i] += delta; | |
5828 | } | |
7e1c0d6f SB |
5829 | } |
5830 | } | |
8d59d221 YA |
5831 | statc->stats_updates = 0; |
5832 | /* We are in a per-cpu loop here, only do the atomic write once */ | |
5833 | if (atomic64_read(&memcg->vmstats->stats_updates)) | |
5834 | atomic64_set(&memcg->vmstats->stats_updates, 0); | |
2d146aa3 JW |
5835 | } |
5836 | ||
02491447 | 5837 | #ifdef CONFIG_MMU |
7dc74be0 | 5838 | /* Handlers for move charge at task migration. */ |
854ffa8d | 5839 | static int mem_cgroup_do_precharge(unsigned long count) |
7dc74be0 | 5840 | { |
05b84301 | 5841 | int ret; |
9476db97 | 5842 | |
d0164adc MG |
5843 | /* Try a single bulk charge without reclaim first, kswapd may wake */ |
5844 | ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_DIRECT_RECLAIM, count); | |
9476db97 | 5845 | if (!ret) { |
854ffa8d | 5846 | mc.precharge += count; |
854ffa8d DN |
5847 | return ret; |
5848 | } | |
9476db97 | 5849 | |
3674534b | 5850 | /* Try charges one by one with reclaim, but do not retry */ |
854ffa8d | 5851 | while (count--) { |
3674534b | 5852 | ret = try_charge(mc.to, GFP_KERNEL | __GFP_NORETRY, 1); |
38c5d72f | 5853 | if (ret) |
38c5d72f | 5854 | return ret; |
854ffa8d | 5855 | mc.precharge++; |
9476db97 | 5856 | cond_resched(); |
854ffa8d | 5857 | } |
9476db97 | 5858 | return 0; |
4ffef5fe DN |
5859 | } |
5860 | ||
4ffef5fe DN |
5861 | union mc_target { |
5862 | struct page *page; | |
02491447 | 5863 | swp_entry_t ent; |
4ffef5fe DN |
5864 | }; |
5865 | ||
4ffef5fe | 5866 | enum mc_target_type { |
8d32ff84 | 5867 | MC_TARGET_NONE = 0, |
4ffef5fe | 5868 | MC_TARGET_PAGE, |
02491447 | 5869 | MC_TARGET_SWAP, |
c733a828 | 5870 | MC_TARGET_DEVICE, |
4ffef5fe DN |
5871 | }; |
5872 | ||
90254a65 DN |
5873 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
5874 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 5875 | { |
25b2995a | 5876 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 5877 | |
58f341f7 | 5878 | if (!page) |
90254a65 DN |
5879 | return NULL; |
5880 | if (PageAnon(page)) { | |
1dfab5ab | 5881 | if (!(mc.flags & MOVE_ANON)) |
90254a65 | 5882 | return NULL; |
1dfab5ab JW |
5883 | } else { |
5884 | if (!(mc.flags & MOVE_FILE)) | |
5885 | return NULL; | |
5886 | } | |
58f341f7 | 5887 | get_page(page); |
90254a65 DN |
5888 | |
5889 | return page; | |
5890 | } | |
5891 | ||
c733a828 | 5892 | #if defined(CONFIG_SWAP) || defined(CONFIG_DEVICE_PRIVATE) |
90254a65 | 5893 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, |
48406ef8 | 5894 | pte_t ptent, swp_entry_t *entry) |
90254a65 | 5895 | { |
90254a65 DN |
5896 | struct page *page = NULL; |
5897 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
5898 | ||
9a137153 | 5899 | if (!(mc.flags & MOVE_ANON)) |
90254a65 | 5900 | return NULL; |
c733a828 JG |
5901 | |
5902 | /* | |
27674ef6 CH |
5903 | * Handle device private pages that are not accessible by the CPU, but |
5904 | * stored as special swap entries in the page table. | |
c733a828 JG |
5905 | */ |
5906 | if (is_device_private_entry(ent)) { | |
af5cdaf8 | 5907 | page = pfn_swap_entry_to_page(ent); |
27674ef6 | 5908 | if (!get_page_unless_zero(page)) |
c733a828 JG |
5909 | return NULL; |
5910 | return page; | |
5911 | } | |
5912 | ||
9a137153 RC |
5913 | if (non_swap_entry(ent)) |
5914 | return NULL; | |
5915 | ||
4b91355e | 5916 | /* |
cb691e2f | 5917 | * Because swap_cache_get_folio() updates some statistics counter, |
4b91355e KH |
5918 | * we call find_get_page() with swapper_space directly. |
5919 | */ | |
f6ab1f7f | 5920 | page = find_get_page(swap_address_space(ent), swp_offset(ent)); |
2d1c4980 | 5921 | entry->val = ent.val; |
90254a65 DN |
5922 | |
5923 | return page; | |
5924 | } | |
4b91355e KH |
5925 | #else |
5926 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
48406ef8 | 5927 | pte_t ptent, swp_entry_t *entry) |
4b91355e KH |
5928 | { |
5929 | return NULL; | |
5930 | } | |
5931 | #endif | |
90254a65 | 5932 | |
87946a72 | 5933 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
48384b0b | 5934 | unsigned long addr, pte_t ptent) |
87946a72 | 5935 | { |
524984ff MWO |
5936 | unsigned long index; |
5937 | struct folio *folio; | |
5938 | ||
87946a72 DN |
5939 | if (!vma->vm_file) /* anonymous vma */ |
5940 | return NULL; | |
1dfab5ab | 5941 | if (!(mc.flags & MOVE_FILE)) |
87946a72 DN |
5942 | return NULL; |
5943 | ||
524984ff | 5944 | /* folio is moved even if it's not RSS of this task(page-faulted). */ |
aa3b1895 | 5945 | /* shmem/tmpfs may report page out on swap: account for that too. */ |
524984ff MWO |
5946 | index = linear_page_index(vma, addr); |
5947 | folio = filemap_get_incore_folio(vma->vm_file->f_mapping, index); | |
66dabbb6 | 5948 | if (IS_ERR(folio)) |
524984ff MWO |
5949 | return NULL; |
5950 | return folio_file_page(folio, index); | |
87946a72 DN |
5951 | } |
5952 | ||
b1b0deab CG |
5953 | /** |
5954 | * mem_cgroup_move_account - move account of the page | |
5955 | * @page: the page | |
25843c2b | 5956 | * @compound: charge the page as compound or small page |
b1b0deab CG |
5957 | * @from: mem_cgroup which the page is moved from. |
5958 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
5959 | * | |
4e0cf05f | 5960 | * The page must be locked and not on the LRU. |
b1b0deab CG |
5961 | * |
5962 | * This function doesn't do "charge" to new cgroup and doesn't do "uncharge" | |
5963 | * from old cgroup. | |
5964 | */ | |
5965 | static int mem_cgroup_move_account(struct page *page, | |
f627c2f5 | 5966 | bool compound, |
b1b0deab CG |
5967 | struct mem_cgroup *from, |
5968 | struct mem_cgroup *to) | |
5969 | { | |
fcce4672 | 5970 | struct folio *folio = page_folio(page); |
ae8af438 KK |
5971 | struct lruvec *from_vec, *to_vec; |
5972 | struct pglist_data *pgdat; | |
fcce4672 | 5973 | unsigned int nr_pages = compound ? folio_nr_pages(folio) : 1; |
8e88bd2d | 5974 | int nid, ret; |
b1b0deab CG |
5975 | |
5976 | VM_BUG_ON(from == to); | |
4e0cf05f | 5977 | VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); |
fcce4672 | 5978 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
9c325215 | 5979 | VM_BUG_ON(compound && !folio_test_large(folio)); |
b1b0deab | 5980 | |
b1b0deab | 5981 | ret = -EINVAL; |
fcce4672 | 5982 | if (folio_memcg(folio) != from) |
4e0cf05f | 5983 | goto out; |
b1b0deab | 5984 | |
fcce4672 | 5985 | pgdat = folio_pgdat(folio); |
867e5e1d JW |
5986 | from_vec = mem_cgroup_lruvec(from, pgdat); |
5987 | to_vec = mem_cgroup_lruvec(to, pgdat); | |
ae8af438 | 5988 | |
fcce4672 | 5989 | folio_memcg_lock(folio); |
b1b0deab | 5990 | |
fcce4672 MWO |
5991 | if (folio_test_anon(folio)) { |
5992 | if (folio_mapped(folio)) { | |
be5d0a74 JW |
5993 | __mod_lruvec_state(from_vec, NR_ANON_MAPPED, -nr_pages); |
5994 | __mod_lruvec_state(to_vec, NR_ANON_MAPPED, nr_pages); | |
6199277b | 5995 | if (folio_test_pmd_mappable(folio)) { |
69473e5d MS |
5996 | __mod_lruvec_state(from_vec, NR_ANON_THPS, |
5997 | -nr_pages); | |
5998 | __mod_lruvec_state(to_vec, NR_ANON_THPS, | |
5999 | nr_pages); | |
468c3982 | 6000 | } |
be5d0a74 JW |
6001 | } |
6002 | } else { | |
0d1c2072 JW |
6003 | __mod_lruvec_state(from_vec, NR_FILE_PAGES, -nr_pages); |
6004 | __mod_lruvec_state(to_vec, NR_FILE_PAGES, nr_pages); | |
6005 | ||
fcce4672 | 6006 | if (folio_test_swapbacked(folio)) { |
0d1c2072 JW |
6007 | __mod_lruvec_state(from_vec, NR_SHMEM, -nr_pages); |
6008 | __mod_lruvec_state(to_vec, NR_SHMEM, nr_pages); | |
6009 | } | |
6010 | ||
fcce4672 | 6011 | if (folio_mapped(folio)) { |
49e50d27 JW |
6012 | __mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages); |
6013 | __mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages); | |
6014 | } | |
b1b0deab | 6015 | |
fcce4672 MWO |
6016 | if (folio_test_dirty(folio)) { |
6017 | struct address_space *mapping = folio_mapping(folio); | |
c4843a75 | 6018 | |
f56753ac | 6019 | if (mapping_can_writeback(mapping)) { |
49e50d27 JW |
6020 | __mod_lruvec_state(from_vec, NR_FILE_DIRTY, |
6021 | -nr_pages); | |
6022 | __mod_lruvec_state(to_vec, NR_FILE_DIRTY, | |
6023 | nr_pages); | |
6024 | } | |
c4843a75 GT |
6025 | } |
6026 | } | |
6027 | ||
c449deb2 HD |
6028 | #ifdef CONFIG_SWAP |
6029 | if (folio_test_swapcache(folio)) { | |
6030 | __mod_lruvec_state(from_vec, NR_SWAPCACHE, -nr_pages); | |
6031 | __mod_lruvec_state(to_vec, NR_SWAPCACHE, nr_pages); | |
6032 | } | |
6033 | #endif | |
fcce4672 | 6034 | if (folio_test_writeback(folio)) { |
ae8af438 KK |
6035 | __mod_lruvec_state(from_vec, NR_WRITEBACK, -nr_pages); |
6036 | __mod_lruvec_state(to_vec, NR_WRITEBACK, nr_pages); | |
b1b0deab CG |
6037 | } |
6038 | ||
6039 | /* | |
abb242f5 JW |
6040 | * All state has been migrated, let's switch to the new memcg. |
6041 | * | |
bcfe06bf | 6042 | * It is safe to change page's memcg here because the page |
abb242f5 JW |
6043 | * is referenced, charged, isolated, and locked: we can't race |
6044 | * with (un)charging, migration, LRU putback, or anything else | |
bcfe06bf | 6045 | * that would rely on a stable page's memory cgroup. |
abb242f5 | 6046 | * |
6c77b607 | 6047 | * Note that folio_memcg_lock is a memcg lock, not a page lock, |
bcfe06bf | 6048 | * to save space. As soon as we switch page's memory cgroup to a |
abb242f5 JW |
6049 | * new memcg that isn't locked, the above state can change |
6050 | * concurrently again. Make sure we're truly done with it. | |
b1b0deab | 6051 | */ |
abb242f5 | 6052 | smp_mb(); |
b1b0deab | 6053 | |
1a3e1f40 JW |
6054 | css_get(&to->css); |
6055 | css_put(&from->css); | |
6056 | ||
fcce4672 | 6057 | folio->memcg_data = (unsigned long)to; |
87eaceb3 | 6058 | |
f70ad448 | 6059 | __folio_memcg_unlock(from); |
b1b0deab CG |
6060 | |
6061 | ret = 0; | |
fcce4672 | 6062 | nid = folio_nid(folio); |
b1b0deab CG |
6063 | |
6064 | local_irq_disable(); | |
6e0110c2 | 6065 | mem_cgroup_charge_statistics(to, nr_pages); |
8e88bd2d | 6066 | memcg_check_events(to, nid); |
6e0110c2 | 6067 | mem_cgroup_charge_statistics(from, -nr_pages); |
8e88bd2d | 6068 | memcg_check_events(from, nid); |
b1b0deab | 6069 | local_irq_enable(); |
b1b0deab CG |
6070 | out: |
6071 | return ret; | |
6072 | } | |
6073 | ||
7cf7806c LR |
6074 | /** |
6075 | * get_mctgt_type - get target type of moving charge | |
6076 | * @vma: the vma the pte to be checked belongs | |
6077 | * @addr: the address corresponding to the pte to be checked | |
6078 | * @ptent: the pte to be checked | |
6079 | * @target: the pointer the target page or swap ent will be stored(can be NULL) | |
6080 | * | |
853f62a3 MWO |
6081 | * Context: Called with pte lock held. |
6082 | * Return: | |
6083 | * * MC_TARGET_NONE - If the pte is not a target for move charge. | |
6084 | * * MC_TARGET_PAGE - If the page corresponding to this pte is a target for | |
6085 | * move charge. If @target is not NULL, the page is stored in target->page | |
6086 | * with extra refcnt taken (Caller should release it). | |
6087 | * * MC_TARGET_SWAP - If the swap entry corresponding to this pte is a | |
6088 | * target for charge migration. If @target is not NULL, the entry is | |
6089 | * stored in target->ent. | |
6090 | * * MC_TARGET_DEVICE - Like MC_TARGET_PAGE but page is device memory and | |
6091 | * thus not on the lru. For now such page is charged like a regular page | |
6092 | * would be as it is just special memory taking the place of a regular page. | |
6093 | * See Documentations/vm/hmm.txt and include/linux/hmm.h | |
7cf7806c | 6094 | */ |
8d32ff84 | 6095 | static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, |
90254a65 DN |
6096 | unsigned long addr, pte_t ptent, union mc_target *target) |
6097 | { | |
6098 | struct page *page = NULL; | |
8d32ff84 | 6099 | enum mc_target_type ret = MC_TARGET_NONE; |
90254a65 DN |
6100 | swp_entry_t ent = { .val = 0 }; |
6101 | ||
6102 | if (pte_present(ptent)) | |
6103 | page = mc_handle_present_pte(vma, addr, ptent); | |
5c041f5d PX |
6104 | else if (pte_none_mostly(ptent)) |
6105 | /* | |
6106 | * PTE markers should be treated as a none pte here, separated | |
6107 | * from other swap handling below. | |
6108 | */ | |
6109 | page = mc_handle_file_pte(vma, addr, ptent); | |
90254a65 | 6110 | else if (is_swap_pte(ptent)) |
48406ef8 | 6111 | page = mc_handle_swap_pte(vma, ptent, &ent); |
90254a65 | 6112 | |
4e0cf05f JW |
6113 | if (target && page) { |
6114 | if (!trylock_page(page)) { | |
6115 | put_page(page); | |
6116 | return ret; | |
6117 | } | |
6118 | /* | |
6119 | * page_mapped() must be stable during the move. This | |
6120 | * pte is locked, so if it's present, the page cannot | |
6121 | * become unmapped. If it isn't, we have only partial | |
6122 | * control over the mapped state: the page lock will | |
6123 | * prevent new faults against pagecache and swapcache, | |
6124 | * so an unmapped page cannot become mapped. However, | |
6125 | * if the page is already mapped elsewhere, it can | |
6126 | * unmap, and there is nothing we can do about it. | |
6127 | * Alas, skip moving the page in this case. | |
6128 | */ | |
6129 | if (!pte_present(ptent) && page_mapped(page)) { | |
6130 | unlock_page(page); | |
6131 | put_page(page); | |
6132 | return ret; | |
6133 | } | |
6134 | } | |
6135 | ||
90254a65 | 6136 | if (!page && !ent.val) |
8d32ff84 | 6137 | return ret; |
02491447 | 6138 | if (page) { |
02491447 | 6139 | /* |
0a31bc97 | 6140 | * Do only loose check w/o serialization. |
1306a85a | 6141 | * mem_cgroup_move_account() checks the page is valid or |
0a31bc97 | 6142 | * not under LRU exclusion. |
02491447 | 6143 | */ |
bcfe06bf | 6144 | if (page_memcg(page) == mc.from) { |
02491447 | 6145 | ret = MC_TARGET_PAGE; |
f25cbb7a AS |
6146 | if (is_device_private_page(page) || |
6147 | is_device_coherent_page(page)) | |
c733a828 | 6148 | ret = MC_TARGET_DEVICE; |
02491447 DN |
6149 | if (target) |
6150 | target->page = page; | |
6151 | } | |
4e0cf05f JW |
6152 | if (!ret || !target) { |
6153 | if (target) | |
6154 | unlock_page(page); | |
02491447 | 6155 | put_page(page); |
4e0cf05f | 6156 | } |
02491447 | 6157 | } |
3e14a57b HY |
6158 | /* |
6159 | * There is a swap entry and a page doesn't exist or isn't charged. | |
6160 | * But we cannot move a tail-page in a THP. | |
6161 | */ | |
6162 | if (ent.val && !ret && (!page || !PageTransCompound(page)) && | |
34c00c31 | 6163 | mem_cgroup_id(mc.from) == lookup_swap_cgroup_id(ent)) { |
7f0f1546 KH |
6164 | ret = MC_TARGET_SWAP; |
6165 | if (target) | |
6166 | target->ent = ent; | |
4ffef5fe | 6167 | } |
4ffef5fe DN |
6168 | return ret; |
6169 | } | |
6170 | ||
12724850 NH |
6171 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
6172 | /* | |
d6810d73 HY |
6173 | * We don't consider PMD mapped swapping or file mapped pages because THP does |
6174 | * not support them for now. | |
12724850 NH |
6175 | * Caller should make sure that pmd_trans_huge(pmd) is true. |
6176 | */ | |
6177 | static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
6178 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
6179 | { | |
6180 | struct page *page = NULL; | |
12724850 NH |
6181 | enum mc_target_type ret = MC_TARGET_NONE; |
6182 | ||
84c3fc4e ZY |
6183 | if (unlikely(is_swap_pmd(pmd))) { |
6184 | VM_BUG_ON(thp_migration_supported() && | |
6185 | !is_pmd_migration_entry(pmd)); | |
6186 | return ret; | |
6187 | } | |
12724850 | 6188 | page = pmd_page(pmd); |
309381fe | 6189 | VM_BUG_ON_PAGE(!page || !PageHead(page), page); |
1dfab5ab | 6190 | if (!(mc.flags & MOVE_ANON)) |
12724850 | 6191 | return ret; |
bcfe06bf | 6192 | if (page_memcg(page) == mc.from) { |
12724850 NH |
6193 | ret = MC_TARGET_PAGE; |
6194 | if (target) { | |
6195 | get_page(page); | |
4e0cf05f JW |
6196 | if (!trylock_page(page)) { |
6197 | put_page(page); | |
6198 | return MC_TARGET_NONE; | |
6199 | } | |
12724850 NH |
6200 | target->page = page; |
6201 | } | |
6202 | } | |
6203 | return ret; | |
6204 | } | |
6205 | #else | |
6206 | static inline enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
6207 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
6208 | { | |
6209 | return MC_TARGET_NONE; | |
6210 | } | |
6211 | #endif | |
6212 | ||
4ffef5fe DN |
6213 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, |
6214 | unsigned long addr, unsigned long end, | |
6215 | struct mm_walk *walk) | |
6216 | { | |
26bcd64a | 6217 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
6218 | pte_t *pte; |
6219 | spinlock_t *ptl; | |
6220 | ||
b6ec57f4 KS |
6221 | ptl = pmd_trans_huge_lock(pmd, vma); |
6222 | if (ptl) { | |
c733a828 JG |
6223 | /* |
6224 | * Note their can not be MC_TARGET_DEVICE for now as we do not | |
25b2995a CH |
6225 | * support transparent huge page with MEMORY_DEVICE_PRIVATE but |
6226 | * this might change. | |
c733a828 | 6227 | */ |
12724850 NH |
6228 | if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE) |
6229 | mc.precharge += HPAGE_PMD_NR; | |
bf929152 | 6230 | spin_unlock(ptl); |
1a5a9906 | 6231 | return 0; |
12724850 | 6232 | } |
03319327 | 6233 | |
4ffef5fe | 6234 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
04dee9e8 HD |
6235 | if (!pte) |
6236 | return 0; | |
4ffef5fe | 6237 | for (; addr != end; pte++, addr += PAGE_SIZE) |
c33c7948 | 6238 | if (get_mctgt_type(vma, addr, ptep_get(pte), NULL)) |
4ffef5fe DN |
6239 | mc.precharge++; /* increment precharge temporarily */ |
6240 | pte_unmap_unlock(pte - 1, ptl); | |
6241 | cond_resched(); | |
6242 | ||
7dc74be0 DN |
6243 | return 0; |
6244 | } | |
6245 | ||
7b86ac33 CH |
6246 | static const struct mm_walk_ops precharge_walk_ops = { |
6247 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
49b06385 | 6248 | .walk_lock = PGWALK_RDLOCK, |
7b86ac33 CH |
6249 | }; |
6250 | ||
4ffef5fe DN |
6251 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
6252 | { | |
6253 | unsigned long precharge; | |
4ffef5fe | 6254 | |
d8ed45c5 | 6255 | mmap_read_lock(mm); |
ba0aff8e | 6256 | walk_page_range(mm, 0, ULONG_MAX, &precharge_walk_ops, NULL); |
d8ed45c5 | 6257 | mmap_read_unlock(mm); |
4ffef5fe DN |
6258 | |
6259 | precharge = mc.precharge; | |
6260 | mc.precharge = 0; | |
6261 | ||
6262 | return precharge; | |
6263 | } | |
6264 | ||
4ffef5fe DN |
6265 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
6266 | { | |
dfe076b0 DN |
6267 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
6268 | ||
6269 | VM_BUG_ON(mc.moving_task); | |
6270 | mc.moving_task = current; | |
6271 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
6272 | } |
6273 | ||
dfe076b0 DN |
6274 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
6275 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 6276 | { |
2bd9bb20 KH |
6277 | struct mem_cgroup *from = mc.from; |
6278 | struct mem_cgroup *to = mc.to; | |
6279 | ||
4ffef5fe | 6280 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d | 6281 | if (mc.precharge) { |
4b569387 | 6282 | mem_cgroup_cancel_charge(mc.to, mc.precharge); |
854ffa8d DN |
6283 | mc.precharge = 0; |
6284 | } | |
6285 | /* | |
6286 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
6287 | * we must uncharge here. | |
6288 | */ | |
6289 | if (mc.moved_charge) { | |
4b569387 | 6290 | mem_cgroup_cancel_charge(mc.from, mc.moved_charge); |
854ffa8d | 6291 | mc.moved_charge = 0; |
4ffef5fe | 6292 | } |
483c30b5 DN |
6293 | /* we must fixup refcnts and charges */ |
6294 | if (mc.moved_swap) { | |
483c30b5 | 6295 | /* uncharge swap account from the old cgroup */ |
ce00a967 | 6296 | if (!mem_cgroup_is_root(mc.from)) |
3e32cb2e | 6297 | page_counter_uncharge(&mc.from->memsw, mc.moved_swap); |
483c30b5 | 6298 | |
615d66c3 VD |
6299 | mem_cgroup_id_put_many(mc.from, mc.moved_swap); |
6300 | ||
05b84301 | 6301 | /* |
3e32cb2e JW |
6302 | * we charged both to->memory and to->memsw, so we |
6303 | * should uncharge to->memory. | |
05b84301 | 6304 | */ |
ce00a967 | 6305 | if (!mem_cgroup_is_root(mc.to)) |
3e32cb2e JW |
6306 | page_counter_uncharge(&mc.to->memory, mc.moved_swap); |
6307 | ||
483c30b5 DN |
6308 | mc.moved_swap = 0; |
6309 | } | |
dfe076b0 DN |
6310 | memcg_oom_recover(from); |
6311 | memcg_oom_recover(to); | |
6312 | wake_up_all(&mc.waitq); | |
6313 | } | |
6314 | ||
6315 | static void mem_cgroup_clear_mc(void) | |
6316 | { | |
264a0ae1 TH |
6317 | struct mm_struct *mm = mc.mm; |
6318 | ||
dfe076b0 DN |
6319 | /* |
6320 | * we must clear moving_task before waking up waiters at the end of | |
6321 | * task migration. | |
6322 | */ | |
6323 | mc.moving_task = NULL; | |
6324 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 6325 | spin_lock(&mc.lock); |
4ffef5fe DN |
6326 | mc.from = NULL; |
6327 | mc.to = NULL; | |
264a0ae1 | 6328 | mc.mm = NULL; |
2bd9bb20 | 6329 | spin_unlock(&mc.lock); |
264a0ae1 TH |
6330 | |
6331 | mmput(mm); | |
4ffef5fe DN |
6332 | } |
6333 | ||
1f7dd3e5 | 6334 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
7dc74be0 | 6335 | { |
1f7dd3e5 | 6336 | struct cgroup_subsys_state *css; |
eed67d75 | 6337 | struct mem_cgroup *memcg = NULL; /* unneeded init to make gcc happy */ |
9f2115f9 | 6338 | struct mem_cgroup *from; |
4530eddb | 6339 | struct task_struct *leader, *p; |
9f2115f9 | 6340 | struct mm_struct *mm; |
1dfab5ab | 6341 | unsigned long move_flags; |
9f2115f9 | 6342 | int ret = 0; |
7dc74be0 | 6343 | |
1f7dd3e5 TH |
6344 | /* charge immigration isn't supported on the default hierarchy */ |
6345 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
9f2115f9 TH |
6346 | return 0; |
6347 | ||
4530eddb TH |
6348 | /* |
6349 | * Multi-process migrations only happen on the default hierarchy | |
6350 | * where charge immigration is not used. Perform charge | |
6351 | * immigration if @tset contains a leader and whine if there are | |
6352 | * multiple. | |
6353 | */ | |
6354 | p = NULL; | |
1f7dd3e5 | 6355 | cgroup_taskset_for_each_leader(leader, css, tset) { |
4530eddb TH |
6356 | WARN_ON_ONCE(p); |
6357 | p = leader; | |
1f7dd3e5 | 6358 | memcg = mem_cgroup_from_css(css); |
4530eddb TH |
6359 | } |
6360 | if (!p) | |
6361 | return 0; | |
6362 | ||
1f7dd3e5 | 6363 | /* |
f0953a1b | 6364 | * We are now committed to this value whatever it is. Changes in this |
1f7dd3e5 TH |
6365 | * tunable will only affect upcoming migrations, not the current one. |
6366 | * So we need to save it, and keep it going. | |
6367 | */ | |
6368 | move_flags = READ_ONCE(memcg->move_charge_at_immigrate); | |
6369 | if (!move_flags) | |
6370 | return 0; | |
6371 | ||
9f2115f9 TH |
6372 | from = mem_cgroup_from_task(p); |
6373 | ||
6374 | VM_BUG_ON(from == memcg); | |
6375 | ||
6376 | mm = get_task_mm(p); | |
6377 | if (!mm) | |
6378 | return 0; | |
6379 | /* We move charges only when we move a owner of the mm */ | |
6380 | if (mm->owner == p) { | |
6381 | VM_BUG_ON(mc.from); | |
6382 | VM_BUG_ON(mc.to); | |
6383 | VM_BUG_ON(mc.precharge); | |
6384 | VM_BUG_ON(mc.moved_charge); | |
6385 | VM_BUG_ON(mc.moved_swap); | |
6386 | ||
6387 | spin_lock(&mc.lock); | |
264a0ae1 | 6388 | mc.mm = mm; |
9f2115f9 TH |
6389 | mc.from = from; |
6390 | mc.to = memcg; | |
6391 | mc.flags = move_flags; | |
6392 | spin_unlock(&mc.lock); | |
6393 | /* We set mc.moving_task later */ | |
6394 | ||
6395 | ret = mem_cgroup_precharge_mc(mm); | |
6396 | if (ret) | |
6397 | mem_cgroup_clear_mc(); | |
264a0ae1 TH |
6398 | } else { |
6399 | mmput(mm); | |
7dc74be0 DN |
6400 | } |
6401 | return ret; | |
6402 | } | |
6403 | ||
1f7dd3e5 | 6404 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
7dc74be0 | 6405 | { |
4e2f245d JW |
6406 | if (mc.to) |
6407 | mem_cgroup_clear_mc(); | |
7dc74be0 DN |
6408 | } |
6409 | ||
4ffef5fe DN |
6410 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
6411 | unsigned long addr, unsigned long end, | |
6412 | struct mm_walk *walk) | |
7dc74be0 | 6413 | { |
4ffef5fe | 6414 | int ret = 0; |
26bcd64a | 6415 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
6416 | pte_t *pte; |
6417 | spinlock_t *ptl; | |
12724850 NH |
6418 | enum mc_target_type target_type; |
6419 | union mc_target target; | |
6420 | struct page *page; | |
4ffef5fe | 6421 | |
b6ec57f4 KS |
6422 | ptl = pmd_trans_huge_lock(pmd, vma); |
6423 | if (ptl) { | |
62ade86a | 6424 | if (mc.precharge < HPAGE_PMD_NR) { |
bf929152 | 6425 | spin_unlock(ptl); |
12724850 NH |
6426 | return 0; |
6427 | } | |
6428 | target_type = get_mctgt_type_thp(vma, addr, *pmd, &target); | |
6429 | if (target_type == MC_TARGET_PAGE) { | |
6430 | page = target.page; | |
f7f9c00d | 6431 | if (isolate_lru_page(page)) { |
f627c2f5 | 6432 | if (!mem_cgroup_move_account(page, true, |
1306a85a | 6433 | mc.from, mc.to)) { |
12724850 NH |
6434 | mc.precharge -= HPAGE_PMD_NR; |
6435 | mc.moved_charge += HPAGE_PMD_NR; | |
6436 | } | |
6437 | putback_lru_page(page); | |
6438 | } | |
4e0cf05f | 6439 | unlock_page(page); |
12724850 | 6440 | put_page(page); |
c733a828 JG |
6441 | } else if (target_type == MC_TARGET_DEVICE) { |
6442 | page = target.page; | |
6443 | if (!mem_cgroup_move_account(page, true, | |
6444 | mc.from, mc.to)) { | |
6445 | mc.precharge -= HPAGE_PMD_NR; | |
6446 | mc.moved_charge += HPAGE_PMD_NR; | |
6447 | } | |
4e0cf05f | 6448 | unlock_page(page); |
c733a828 | 6449 | put_page(page); |
12724850 | 6450 | } |
bf929152 | 6451 | spin_unlock(ptl); |
1a5a9906 | 6452 | return 0; |
12724850 NH |
6453 | } |
6454 | ||
4ffef5fe DN |
6455 | retry: |
6456 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
04dee9e8 HD |
6457 | if (!pte) |
6458 | return 0; | |
4ffef5fe | 6459 | for (; addr != end; addr += PAGE_SIZE) { |
c33c7948 | 6460 | pte_t ptent = ptep_get(pte++); |
c733a828 | 6461 | bool device = false; |
02491447 | 6462 | swp_entry_t ent; |
4ffef5fe DN |
6463 | |
6464 | if (!mc.precharge) | |
6465 | break; | |
6466 | ||
8d32ff84 | 6467 | switch (get_mctgt_type(vma, addr, ptent, &target)) { |
c733a828 JG |
6468 | case MC_TARGET_DEVICE: |
6469 | device = true; | |
e4a9bc58 | 6470 | fallthrough; |
4ffef5fe DN |
6471 | case MC_TARGET_PAGE: |
6472 | page = target.page; | |
53f9263b KS |
6473 | /* |
6474 | * We can have a part of the split pmd here. Moving it | |
6475 | * can be done but it would be too convoluted so simply | |
6476 | * ignore such a partial THP and keep it in original | |
6477 | * memcg. There should be somebody mapping the head. | |
6478 | */ | |
6479 | if (PageTransCompound(page)) | |
6480 | goto put; | |
f7f9c00d | 6481 | if (!device && !isolate_lru_page(page)) |
4ffef5fe | 6482 | goto put; |
f627c2f5 KS |
6483 | if (!mem_cgroup_move_account(page, false, |
6484 | mc.from, mc.to)) { | |
4ffef5fe | 6485 | mc.precharge--; |
854ffa8d DN |
6486 | /* we uncharge from mc.from later. */ |
6487 | mc.moved_charge++; | |
4ffef5fe | 6488 | } |
c733a828 JG |
6489 | if (!device) |
6490 | putback_lru_page(page); | |
4e0cf05f JW |
6491 | put: /* get_mctgt_type() gets & locks the page */ |
6492 | unlock_page(page); | |
4ffef5fe DN |
6493 | put_page(page); |
6494 | break; | |
02491447 DN |
6495 | case MC_TARGET_SWAP: |
6496 | ent = target.ent; | |
e91cbb42 | 6497 | if (!mem_cgroup_move_swap_account(ent, mc.from, mc.to)) { |
02491447 | 6498 | mc.precharge--; |
8d22a935 HD |
6499 | mem_cgroup_id_get_many(mc.to, 1); |
6500 | /* we fixup other refcnts and charges later. */ | |
483c30b5 DN |
6501 | mc.moved_swap++; |
6502 | } | |
02491447 | 6503 | break; |
4ffef5fe DN |
6504 | default: |
6505 | break; | |
6506 | } | |
6507 | } | |
6508 | pte_unmap_unlock(pte - 1, ptl); | |
6509 | cond_resched(); | |
6510 | ||
6511 | if (addr != end) { | |
6512 | /* | |
6513 | * We have consumed all precharges we got in can_attach(). | |
6514 | * We try charge one by one, but don't do any additional | |
6515 | * charges to mc.to if we have failed in charge once in attach() | |
6516 | * phase. | |
6517 | */ | |
854ffa8d | 6518 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
6519 | if (!ret) |
6520 | goto retry; | |
6521 | } | |
6522 | ||
6523 | return ret; | |
6524 | } | |
6525 | ||
7b86ac33 CH |
6526 | static const struct mm_walk_ops charge_walk_ops = { |
6527 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
49b06385 | 6528 | .walk_lock = PGWALK_RDLOCK, |
7b86ac33 CH |
6529 | }; |
6530 | ||
264a0ae1 | 6531 | static void mem_cgroup_move_charge(void) |
4ffef5fe | 6532 | { |
4ffef5fe | 6533 | lru_add_drain_all(); |
312722cb | 6534 | /* |
6c77b607 | 6535 | * Signal folio_memcg_lock() to take the memcg's move_lock |
81f8c3a4 JW |
6536 | * while we're moving its pages to another memcg. Then wait |
6537 | * for already started RCU-only updates to finish. | |
312722cb JW |
6538 | */ |
6539 | atomic_inc(&mc.from->moving_account); | |
6540 | synchronize_rcu(); | |
dfe076b0 | 6541 | retry: |
d8ed45c5 | 6542 | if (unlikely(!mmap_read_trylock(mc.mm))) { |
dfe076b0 | 6543 | /* |
c1e8d7c6 | 6544 | * Someone who are holding the mmap_lock might be waiting in |
dfe076b0 DN |
6545 | * waitq. So we cancel all extra charges, wake up all waiters, |
6546 | * and retry. Because we cancel precharges, we might not be able | |
6547 | * to move enough charges, but moving charge is a best-effort | |
6548 | * feature anyway, so it wouldn't be a big problem. | |
6549 | */ | |
6550 | __mem_cgroup_clear_mc(); | |
6551 | cond_resched(); | |
6552 | goto retry; | |
6553 | } | |
26bcd64a NH |
6554 | /* |
6555 | * When we have consumed all precharges and failed in doing | |
6556 | * additional charge, the page walk just aborts. | |
6557 | */ | |
ba0aff8e | 6558 | walk_page_range(mc.mm, 0, ULONG_MAX, &charge_walk_ops, NULL); |
d8ed45c5 | 6559 | mmap_read_unlock(mc.mm); |
312722cb | 6560 | atomic_dec(&mc.from->moving_account); |
7dc74be0 DN |
6561 | } |
6562 | ||
264a0ae1 | 6563 | static void mem_cgroup_move_task(void) |
67e465a7 | 6564 | { |
264a0ae1 TH |
6565 | if (mc.to) { |
6566 | mem_cgroup_move_charge(); | |
a433658c | 6567 | mem_cgroup_clear_mc(); |
264a0ae1 | 6568 | } |
67e465a7 | 6569 | } |
1aacbd35 | 6570 | |
5cfb80a7 | 6571 | #else /* !CONFIG_MMU */ |
1f7dd3e5 | 6572 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
6573 | { |
6574 | return 0; | |
6575 | } | |
1f7dd3e5 | 6576 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
6577 | { |
6578 | } | |
264a0ae1 | 6579 | static void mem_cgroup_move_task(void) |
5cfb80a7 DN |
6580 | { |
6581 | } | |
6582 | #endif | |
67e465a7 | 6583 | |
1aacbd35 RG |
6584 | #ifdef CONFIG_MEMCG_KMEM |
6585 | static void mem_cgroup_fork(struct task_struct *task) | |
6586 | { | |
6587 | /* | |
6588 | * Set the update flag to cause task->objcg to be initialized lazily | |
6589 | * on the first allocation. It can be done without any synchronization | |
6590 | * because it's always performed on the current task, so does | |
6591 | * current_objcg_update(). | |
6592 | */ | |
6593 | task->objcg = (struct obj_cgroup *)CURRENT_OBJCG_UPDATE_FLAG; | |
6594 | } | |
6595 | ||
6596 | static void mem_cgroup_exit(struct task_struct *task) | |
6597 | { | |
6598 | struct obj_cgroup *objcg = task->objcg; | |
6599 | ||
6600 | objcg = (struct obj_cgroup *) | |
6601 | ((unsigned long)objcg & ~CURRENT_OBJCG_UPDATE_FLAG); | |
6602 | if (objcg) | |
6603 | obj_cgroup_put(objcg); | |
6604 | ||
6605 | /* | |
6606 | * Some kernel allocations can happen after this point, | |
6607 | * but let's ignore them. It can be done without any synchronization | |
6608 | * because it's always performed on the current task, so does | |
6609 | * current_objcg_update(). | |
6610 | */ | |
6611 | task->objcg = NULL; | |
6612 | } | |
6613 | #endif | |
6614 | ||
bd74fdae | 6615 | #ifdef CONFIG_LRU_GEN |
1aacbd35 | 6616 | static void mem_cgroup_lru_gen_attach(struct cgroup_taskset *tset) |
bd74fdae YZ |
6617 | { |
6618 | struct task_struct *task; | |
6619 | struct cgroup_subsys_state *css; | |
6620 | ||
6621 | /* find the first leader if there is any */ | |
6622 | cgroup_taskset_for_each_leader(task, css, tset) | |
6623 | break; | |
6624 | ||
6625 | if (!task) | |
6626 | return; | |
6627 | ||
6628 | task_lock(task); | |
6629 | if (task->mm && READ_ONCE(task->mm->owner) == task) | |
6630 | lru_gen_migrate_mm(task->mm); | |
6631 | task_unlock(task); | |
6632 | } | |
6633 | #else | |
1aacbd35 RG |
6634 | static void mem_cgroup_lru_gen_attach(struct cgroup_taskset *tset) {} |
6635 | #endif /* CONFIG_LRU_GEN */ | |
6636 | ||
6637 | #ifdef CONFIG_MEMCG_KMEM | |
6638 | static void mem_cgroup_kmem_attach(struct cgroup_taskset *tset) | |
6639 | { | |
6640 | struct task_struct *task; | |
6641 | struct cgroup_subsys_state *css; | |
6642 | ||
6643 | cgroup_taskset_for_each(task, css, tset) { | |
6644 | /* atomically set the update bit */ | |
6645 | set_bit(CURRENT_OBJCG_UPDATE_BIT, (unsigned long *)&task->objcg); | |
6646 | } | |
6647 | } | |
6648 | #else | |
6649 | static void mem_cgroup_kmem_attach(struct cgroup_taskset *tset) {} | |
6650 | #endif /* CONFIG_MEMCG_KMEM */ | |
6651 | ||
6652 | #if defined(CONFIG_LRU_GEN) || defined(CONFIG_MEMCG_KMEM) | |
bd74fdae YZ |
6653 | static void mem_cgroup_attach(struct cgroup_taskset *tset) |
6654 | { | |
1aacbd35 RG |
6655 | mem_cgroup_lru_gen_attach(tset); |
6656 | mem_cgroup_kmem_attach(tset); | |
bd74fdae | 6657 | } |
1aacbd35 | 6658 | #endif |
bd74fdae | 6659 | |
677dc973 CD |
6660 | static int seq_puts_memcg_tunable(struct seq_file *m, unsigned long value) |
6661 | { | |
6662 | if (value == PAGE_COUNTER_MAX) | |
6663 | seq_puts(m, "max\n"); | |
6664 | else | |
6665 | seq_printf(m, "%llu\n", (u64)value * PAGE_SIZE); | |
6666 | ||
6667 | return 0; | |
6668 | } | |
6669 | ||
241994ed JW |
6670 | static u64 memory_current_read(struct cgroup_subsys_state *css, |
6671 | struct cftype *cft) | |
6672 | { | |
f5fc3c5d JW |
6673 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
6674 | ||
6675 | return (u64)page_counter_read(&memcg->memory) * PAGE_SIZE; | |
241994ed JW |
6676 | } |
6677 | ||
8e20d4b3 GR |
6678 | static u64 memory_peak_read(struct cgroup_subsys_state *css, |
6679 | struct cftype *cft) | |
6680 | { | |
6681 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
6682 | ||
6683 | return (u64)memcg->memory.watermark * PAGE_SIZE; | |
6684 | } | |
6685 | ||
bf8d5d52 RG |
6686 | static int memory_min_show(struct seq_file *m, void *v) |
6687 | { | |
677dc973 CD |
6688 | return seq_puts_memcg_tunable(m, |
6689 | READ_ONCE(mem_cgroup_from_seq(m)->memory.min)); | |
bf8d5d52 RG |
6690 | } |
6691 | ||
6692 | static ssize_t memory_min_write(struct kernfs_open_file *of, | |
6693 | char *buf, size_t nbytes, loff_t off) | |
6694 | { | |
6695 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6696 | unsigned long min; | |
6697 | int err; | |
6698 | ||
6699 | buf = strstrip(buf); | |
6700 | err = page_counter_memparse(buf, "max", &min); | |
6701 | if (err) | |
6702 | return err; | |
6703 | ||
6704 | page_counter_set_min(&memcg->memory, min); | |
6705 | ||
6706 | return nbytes; | |
6707 | } | |
6708 | ||
241994ed JW |
6709 | static int memory_low_show(struct seq_file *m, void *v) |
6710 | { | |
677dc973 CD |
6711 | return seq_puts_memcg_tunable(m, |
6712 | READ_ONCE(mem_cgroup_from_seq(m)->memory.low)); | |
241994ed JW |
6713 | } |
6714 | ||
6715 | static ssize_t memory_low_write(struct kernfs_open_file *of, | |
6716 | char *buf, size_t nbytes, loff_t off) | |
6717 | { | |
6718 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6719 | unsigned long low; | |
6720 | int err; | |
6721 | ||
6722 | buf = strstrip(buf); | |
d2973697 | 6723 | err = page_counter_memparse(buf, "max", &low); |
241994ed JW |
6724 | if (err) |
6725 | return err; | |
6726 | ||
23067153 | 6727 | page_counter_set_low(&memcg->memory, low); |
241994ed JW |
6728 | |
6729 | return nbytes; | |
6730 | } | |
6731 | ||
6732 | static int memory_high_show(struct seq_file *m, void *v) | |
6733 | { | |
d1663a90 JK |
6734 | return seq_puts_memcg_tunable(m, |
6735 | READ_ONCE(mem_cgroup_from_seq(m)->memory.high)); | |
241994ed JW |
6736 | } |
6737 | ||
6738 | static ssize_t memory_high_write(struct kernfs_open_file *of, | |
6739 | char *buf, size_t nbytes, loff_t off) | |
6740 | { | |
6741 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
d977aa93 | 6742 | unsigned int nr_retries = MAX_RECLAIM_RETRIES; |
8c8c383c | 6743 | bool drained = false; |
241994ed JW |
6744 | unsigned long high; |
6745 | int err; | |
6746 | ||
6747 | buf = strstrip(buf); | |
d2973697 | 6748 | err = page_counter_memparse(buf, "max", &high); |
241994ed JW |
6749 | if (err) |
6750 | return err; | |
6751 | ||
e82553c1 JW |
6752 | page_counter_set_high(&memcg->memory, high); |
6753 | ||
8c8c383c JW |
6754 | for (;;) { |
6755 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
6756 | unsigned long reclaimed; | |
6757 | ||
6758 | if (nr_pages <= high) | |
6759 | break; | |
6760 | ||
6761 | if (signal_pending(current)) | |
6762 | break; | |
6763 | ||
6764 | if (!drained) { | |
6765 | drain_all_stock(memcg); | |
6766 | drained = true; | |
6767 | continue; | |
6768 | } | |
6769 | ||
6770 | reclaimed = try_to_free_mem_cgroup_pages(memcg, nr_pages - high, | |
55ab834a | 6771 | GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP); |
8c8c383c JW |
6772 | |
6773 | if (!reclaimed && !nr_retries--) | |
6774 | break; | |
6775 | } | |
588083bb | 6776 | |
19ce33ac | 6777 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
6778 | return nbytes; |
6779 | } | |
6780 | ||
6781 | static int memory_max_show(struct seq_file *m, void *v) | |
6782 | { | |
677dc973 CD |
6783 | return seq_puts_memcg_tunable(m, |
6784 | READ_ONCE(mem_cgroup_from_seq(m)->memory.max)); | |
241994ed JW |
6785 | } |
6786 | ||
6787 | static ssize_t memory_max_write(struct kernfs_open_file *of, | |
6788 | char *buf, size_t nbytes, loff_t off) | |
6789 | { | |
6790 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
d977aa93 | 6791 | unsigned int nr_reclaims = MAX_RECLAIM_RETRIES; |
b6e6edcf | 6792 | bool drained = false; |
241994ed JW |
6793 | unsigned long max; |
6794 | int err; | |
6795 | ||
6796 | buf = strstrip(buf); | |
d2973697 | 6797 | err = page_counter_memparse(buf, "max", &max); |
241994ed JW |
6798 | if (err) |
6799 | return err; | |
6800 | ||
bbec2e15 | 6801 | xchg(&memcg->memory.max, max); |
b6e6edcf JW |
6802 | |
6803 | for (;;) { | |
6804 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
6805 | ||
6806 | if (nr_pages <= max) | |
6807 | break; | |
6808 | ||
7249c9f0 | 6809 | if (signal_pending(current)) |
b6e6edcf | 6810 | break; |
b6e6edcf JW |
6811 | |
6812 | if (!drained) { | |
6813 | drain_all_stock(memcg); | |
6814 | drained = true; | |
6815 | continue; | |
6816 | } | |
6817 | ||
6818 | if (nr_reclaims) { | |
6819 | if (!try_to_free_mem_cgroup_pages(memcg, nr_pages - max, | |
55ab834a | 6820 | GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP)) |
b6e6edcf JW |
6821 | nr_reclaims--; |
6822 | continue; | |
6823 | } | |
6824 | ||
e27be240 | 6825 | memcg_memory_event(memcg, MEMCG_OOM); |
b6e6edcf JW |
6826 | if (!mem_cgroup_out_of_memory(memcg, GFP_KERNEL, 0)) |
6827 | break; | |
6828 | } | |
241994ed | 6829 | |
2529bb3a | 6830 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
6831 | return nbytes; |
6832 | } | |
6833 | ||
664dc218 DR |
6834 | /* |
6835 | * Note: don't forget to update the 'samples/cgroup/memcg_event_listener' | |
6836 | * if any new events become available. | |
6837 | */ | |
1e577f97 SB |
6838 | static void __memory_events_show(struct seq_file *m, atomic_long_t *events) |
6839 | { | |
6840 | seq_printf(m, "low %lu\n", atomic_long_read(&events[MEMCG_LOW])); | |
6841 | seq_printf(m, "high %lu\n", atomic_long_read(&events[MEMCG_HIGH])); | |
6842 | seq_printf(m, "max %lu\n", atomic_long_read(&events[MEMCG_MAX])); | |
6843 | seq_printf(m, "oom %lu\n", atomic_long_read(&events[MEMCG_OOM])); | |
6844 | seq_printf(m, "oom_kill %lu\n", | |
6845 | atomic_long_read(&events[MEMCG_OOM_KILL])); | |
b6bf9abb DS |
6846 | seq_printf(m, "oom_group_kill %lu\n", |
6847 | atomic_long_read(&events[MEMCG_OOM_GROUP_KILL])); | |
1e577f97 SB |
6848 | } |
6849 | ||
241994ed JW |
6850 | static int memory_events_show(struct seq_file *m, void *v) |
6851 | { | |
aa9694bb | 6852 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
241994ed | 6853 | |
1e577f97 SB |
6854 | __memory_events_show(m, memcg->memory_events); |
6855 | return 0; | |
6856 | } | |
6857 | ||
6858 | static int memory_events_local_show(struct seq_file *m, void *v) | |
6859 | { | |
6860 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); | |
241994ed | 6861 | |
1e577f97 | 6862 | __memory_events_show(m, memcg->memory_events_local); |
241994ed JW |
6863 | return 0; |
6864 | } | |
6865 | ||
587d9f72 JW |
6866 | static int memory_stat_show(struct seq_file *m, void *v) |
6867 | { | |
aa9694bb | 6868 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
68aaee14 | 6869 | char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL); |
5b42360c | 6870 | struct seq_buf s; |
1ff9e6e1 | 6871 | |
c8713d0b JW |
6872 | if (!buf) |
6873 | return -ENOMEM; | |
5b42360c YA |
6874 | seq_buf_init(&s, buf, PAGE_SIZE); |
6875 | memory_stat_format(memcg, &s); | |
c8713d0b JW |
6876 | seq_puts(m, buf); |
6877 | kfree(buf); | |
587d9f72 JW |
6878 | return 0; |
6879 | } | |
6880 | ||
5f9a4f4a | 6881 | #ifdef CONFIG_NUMA |
fff66b79 MS |
6882 | static inline unsigned long lruvec_page_state_output(struct lruvec *lruvec, |
6883 | int item) | |
6884 | { | |
ff841a06 YA |
6885 | return lruvec_page_state(lruvec, item) * |
6886 | memcg_page_state_output_unit(item); | |
fff66b79 MS |
6887 | } |
6888 | ||
5f9a4f4a MS |
6889 | static int memory_numa_stat_show(struct seq_file *m, void *v) |
6890 | { | |
6891 | int i; | |
6892 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); | |
6893 | ||
7d7ef0a4 | 6894 | mem_cgroup_flush_stats(memcg); |
7e1c0d6f | 6895 | |
5f9a4f4a MS |
6896 | for (i = 0; i < ARRAY_SIZE(memory_stats); i++) { |
6897 | int nid; | |
6898 | ||
6899 | if (memory_stats[i].idx >= NR_VM_NODE_STAT_ITEMS) | |
6900 | continue; | |
6901 | ||
6902 | seq_printf(m, "%s", memory_stats[i].name); | |
6903 | for_each_node_state(nid, N_MEMORY) { | |
6904 | u64 size; | |
6905 | struct lruvec *lruvec; | |
6906 | ||
6907 | lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); | |
fff66b79 MS |
6908 | size = lruvec_page_state_output(lruvec, |
6909 | memory_stats[i].idx); | |
5f9a4f4a MS |
6910 | seq_printf(m, " N%d=%llu", nid, size); |
6911 | } | |
6912 | seq_putc(m, '\n'); | |
6913 | } | |
6914 | ||
6915 | return 0; | |
6916 | } | |
6917 | #endif | |
6918 | ||
3d8b38eb RG |
6919 | static int memory_oom_group_show(struct seq_file *m, void *v) |
6920 | { | |
aa9694bb | 6921 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
3d8b38eb | 6922 | |
eaf7b66b | 6923 | seq_printf(m, "%d\n", READ_ONCE(memcg->oom_group)); |
3d8b38eb RG |
6924 | |
6925 | return 0; | |
6926 | } | |
6927 | ||
6928 | static ssize_t memory_oom_group_write(struct kernfs_open_file *of, | |
6929 | char *buf, size_t nbytes, loff_t off) | |
6930 | { | |
6931 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6932 | int ret, oom_group; | |
6933 | ||
6934 | buf = strstrip(buf); | |
6935 | if (!buf) | |
6936 | return -EINVAL; | |
6937 | ||
6938 | ret = kstrtoint(buf, 0, &oom_group); | |
6939 | if (ret) | |
6940 | return ret; | |
6941 | ||
6942 | if (oom_group != 0 && oom_group != 1) | |
6943 | return -EINVAL; | |
6944 | ||
eaf7b66b | 6945 | WRITE_ONCE(memcg->oom_group, oom_group); |
3d8b38eb RG |
6946 | |
6947 | return nbytes; | |
6948 | } | |
6949 | ||
94968384 SB |
6950 | static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf, |
6951 | size_t nbytes, loff_t off) | |
6952 | { | |
6953 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6954 | unsigned int nr_retries = MAX_RECLAIM_RETRIES; | |
6955 | unsigned long nr_to_reclaim, nr_reclaimed = 0; | |
55ab834a MH |
6956 | unsigned int reclaim_options; |
6957 | int err; | |
12a5d395 MA |
6958 | |
6959 | buf = strstrip(buf); | |
55ab834a MH |
6960 | err = page_counter_memparse(buf, "", &nr_to_reclaim); |
6961 | if (err) | |
6962 | return err; | |
12a5d395 | 6963 | |
55ab834a | 6964 | reclaim_options = MEMCG_RECLAIM_MAY_SWAP | MEMCG_RECLAIM_PROACTIVE; |
94968384 SB |
6965 | while (nr_reclaimed < nr_to_reclaim) { |
6966 | unsigned long reclaimed; | |
6967 | ||
6968 | if (signal_pending(current)) | |
6969 | return -EINTR; | |
6970 | ||
6971 | /* | |
6972 | * This is the final attempt, drain percpu lru caches in the | |
6973 | * hope of introducing more evictable pages for | |
6974 | * try_to_free_mem_cgroup_pages(). | |
6975 | */ | |
6976 | if (!nr_retries) | |
6977 | lru_add_drain_all(); | |
6978 | ||
6979 | reclaimed = try_to_free_mem_cgroup_pages(memcg, | |
0388536a EY |
6980 | min(nr_to_reclaim - nr_reclaimed, SWAP_CLUSTER_MAX), |
6981 | GFP_KERNEL, reclaim_options); | |
94968384 SB |
6982 | |
6983 | if (!reclaimed && !nr_retries--) | |
6984 | return -EAGAIN; | |
6985 | ||
6986 | nr_reclaimed += reclaimed; | |
6987 | } | |
6988 | ||
6989 | return nbytes; | |
6990 | } | |
6991 | ||
241994ed JW |
6992 | static struct cftype memory_files[] = { |
6993 | { | |
6994 | .name = "current", | |
f5fc3c5d | 6995 | .flags = CFTYPE_NOT_ON_ROOT, |
241994ed JW |
6996 | .read_u64 = memory_current_read, |
6997 | }, | |
8e20d4b3 GR |
6998 | { |
6999 | .name = "peak", | |
7000 | .flags = CFTYPE_NOT_ON_ROOT, | |
7001 | .read_u64 = memory_peak_read, | |
7002 | }, | |
bf8d5d52 RG |
7003 | { |
7004 | .name = "min", | |
7005 | .flags = CFTYPE_NOT_ON_ROOT, | |
7006 | .seq_show = memory_min_show, | |
7007 | .write = memory_min_write, | |
7008 | }, | |
241994ed JW |
7009 | { |
7010 | .name = "low", | |
7011 | .flags = CFTYPE_NOT_ON_ROOT, | |
7012 | .seq_show = memory_low_show, | |
7013 | .write = memory_low_write, | |
7014 | }, | |
7015 | { | |
7016 | .name = "high", | |
7017 | .flags = CFTYPE_NOT_ON_ROOT, | |
7018 | .seq_show = memory_high_show, | |
7019 | .write = memory_high_write, | |
7020 | }, | |
7021 | { | |
7022 | .name = "max", | |
7023 | .flags = CFTYPE_NOT_ON_ROOT, | |
7024 | .seq_show = memory_max_show, | |
7025 | .write = memory_max_write, | |
7026 | }, | |
7027 | { | |
7028 | .name = "events", | |
7029 | .flags = CFTYPE_NOT_ON_ROOT, | |
472912a2 | 7030 | .file_offset = offsetof(struct mem_cgroup, events_file), |
241994ed JW |
7031 | .seq_show = memory_events_show, |
7032 | }, | |
1e577f97 SB |
7033 | { |
7034 | .name = "events.local", | |
7035 | .flags = CFTYPE_NOT_ON_ROOT, | |
7036 | .file_offset = offsetof(struct mem_cgroup, events_local_file), | |
7037 | .seq_show = memory_events_local_show, | |
7038 | }, | |
587d9f72 JW |
7039 | { |
7040 | .name = "stat", | |
587d9f72 JW |
7041 | .seq_show = memory_stat_show, |
7042 | }, | |
5f9a4f4a MS |
7043 | #ifdef CONFIG_NUMA |
7044 | { | |
7045 | .name = "numa_stat", | |
7046 | .seq_show = memory_numa_stat_show, | |
7047 | }, | |
7048 | #endif | |
3d8b38eb RG |
7049 | { |
7050 | .name = "oom.group", | |
7051 | .flags = CFTYPE_NOT_ON_ROOT | CFTYPE_NS_DELEGATABLE, | |
7052 | .seq_show = memory_oom_group_show, | |
7053 | .write = memory_oom_group_write, | |
7054 | }, | |
94968384 SB |
7055 | { |
7056 | .name = "reclaim", | |
7057 | .flags = CFTYPE_NS_DELEGATABLE, | |
7058 | .write = memory_reclaim, | |
7059 | }, | |
241994ed JW |
7060 | { } /* terminate */ |
7061 | }; | |
7062 | ||
073219e9 | 7063 | struct cgroup_subsys memory_cgrp_subsys = { |
92fb9748 | 7064 | .css_alloc = mem_cgroup_css_alloc, |
d142e3e6 | 7065 | .css_online = mem_cgroup_css_online, |
92fb9748 | 7066 | .css_offline = mem_cgroup_css_offline, |
6df38689 | 7067 | .css_released = mem_cgroup_css_released, |
92fb9748 | 7068 | .css_free = mem_cgroup_css_free, |
1ced953b | 7069 | .css_reset = mem_cgroup_css_reset, |
2d146aa3 | 7070 | .css_rstat_flush = mem_cgroup_css_rstat_flush, |
7dc74be0 | 7071 | .can_attach = mem_cgroup_can_attach, |
1aacbd35 | 7072 | #if defined(CONFIG_LRU_GEN) || defined(CONFIG_MEMCG_KMEM) |
bd74fdae | 7073 | .attach = mem_cgroup_attach, |
1aacbd35 | 7074 | #endif |
7dc74be0 | 7075 | .cancel_attach = mem_cgroup_cancel_attach, |
264a0ae1 | 7076 | .post_attach = mem_cgroup_move_task, |
1aacbd35 RG |
7077 | #ifdef CONFIG_MEMCG_KMEM |
7078 | .fork = mem_cgroup_fork, | |
7079 | .exit = mem_cgroup_exit, | |
7080 | #endif | |
241994ed JW |
7081 | .dfl_cftypes = memory_files, |
7082 | .legacy_cftypes = mem_cgroup_legacy_files, | |
6d12e2d8 | 7083 | .early_init = 0, |
8cdea7c0 | 7084 | }; |
c077719b | 7085 | |
bc50bcc6 JW |
7086 | /* |
7087 | * This function calculates an individual cgroup's effective | |
7088 | * protection which is derived from its own memory.min/low, its | |
7089 | * parent's and siblings' settings, as well as the actual memory | |
7090 | * distribution in the tree. | |
7091 | * | |
7092 | * The following rules apply to the effective protection values: | |
7093 | * | |
7094 | * 1. At the first level of reclaim, effective protection is equal to | |
7095 | * the declared protection in memory.min and memory.low. | |
7096 | * | |
7097 | * 2. To enable safe delegation of the protection configuration, at | |
7098 | * subsequent levels the effective protection is capped to the | |
7099 | * parent's effective protection. | |
7100 | * | |
7101 | * 3. To make complex and dynamic subtrees easier to configure, the | |
7102 | * user is allowed to overcommit the declared protection at a given | |
7103 | * level. If that is the case, the parent's effective protection is | |
7104 | * distributed to the children in proportion to how much protection | |
7105 | * they have declared and how much of it they are utilizing. | |
7106 | * | |
7107 | * This makes distribution proportional, but also work-conserving: | |
7108 | * if one cgroup claims much more protection than it uses memory, | |
7109 | * the unused remainder is available to its siblings. | |
7110 | * | |
7111 | * 4. Conversely, when the declared protection is undercommitted at a | |
7112 | * given level, the distribution of the larger parental protection | |
7113 | * budget is NOT proportional. A cgroup's protection from a sibling | |
7114 | * is capped to its own memory.min/low setting. | |
7115 | * | |
8a931f80 JW |
7116 | * 5. However, to allow protecting recursive subtrees from each other |
7117 | * without having to declare each individual cgroup's fixed share | |
7118 | * of the ancestor's claim to protection, any unutilized - | |
7119 | * "floating" - protection from up the tree is distributed in | |
7120 | * proportion to each cgroup's *usage*. This makes the protection | |
7121 | * neutral wrt sibling cgroups and lets them compete freely over | |
7122 | * the shared parental protection budget, but it protects the | |
7123 | * subtree as a whole from neighboring subtrees. | |
7124 | * | |
7125 | * Note that 4. and 5. are not in conflict: 4. is about protecting | |
7126 | * against immediate siblings whereas 5. is about protecting against | |
7127 | * neighboring subtrees. | |
bc50bcc6 JW |
7128 | */ |
7129 | static unsigned long effective_protection(unsigned long usage, | |
8a931f80 | 7130 | unsigned long parent_usage, |
bc50bcc6 JW |
7131 | unsigned long setting, |
7132 | unsigned long parent_effective, | |
7133 | unsigned long siblings_protected) | |
7134 | { | |
7135 | unsigned long protected; | |
8a931f80 | 7136 | unsigned long ep; |
bc50bcc6 JW |
7137 | |
7138 | protected = min(usage, setting); | |
7139 | /* | |
7140 | * If all cgroups at this level combined claim and use more | |
08e0f49e | 7141 | * protection than what the parent affords them, distribute |
bc50bcc6 JW |
7142 | * shares in proportion to utilization. |
7143 | * | |
7144 | * We are using actual utilization rather than the statically | |
7145 | * claimed protection in order to be work-conserving: claimed | |
7146 | * but unused protection is available to siblings that would | |
7147 | * otherwise get a smaller chunk than what they claimed. | |
7148 | */ | |
7149 | if (siblings_protected > parent_effective) | |
7150 | return protected * parent_effective / siblings_protected; | |
7151 | ||
7152 | /* | |
7153 | * Ok, utilized protection of all children is within what the | |
7154 | * parent affords them, so we know whatever this child claims | |
7155 | * and utilizes is effectively protected. | |
7156 | * | |
7157 | * If there is unprotected usage beyond this value, reclaim | |
7158 | * will apply pressure in proportion to that amount. | |
7159 | * | |
7160 | * If there is unutilized protection, the cgroup will be fully | |
7161 | * shielded from reclaim, but we do return a smaller value for | |
7162 | * protection than what the group could enjoy in theory. This | |
7163 | * is okay. With the overcommit distribution above, effective | |
7164 | * protection is always dependent on how memory is actually | |
7165 | * consumed among the siblings anyway. | |
7166 | */ | |
8a931f80 JW |
7167 | ep = protected; |
7168 | ||
7169 | /* | |
7170 | * If the children aren't claiming (all of) the protection | |
7171 | * afforded to them by the parent, distribute the remainder in | |
7172 | * proportion to the (unprotected) memory of each cgroup. That | |
7173 | * way, cgroups that aren't explicitly prioritized wrt each | |
7174 | * other compete freely over the allowance, but they are | |
7175 | * collectively protected from neighboring trees. | |
7176 | * | |
7177 | * We're using unprotected memory for the weight so that if | |
7178 | * some cgroups DO claim explicit protection, we don't protect | |
7179 | * the same bytes twice. | |
cd324edc JW |
7180 | * |
7181 | * Check both usage and parent_usage against the respective | |
7182 | * protected values. One should imply the other, but they | |
7183 | * aren't read atomically - make sure the division is sane. | |
8a931f80 JW |
7184 | */ |
7185 | if (!(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_RECURSIVE_PROT)) | |
7186 | return ep; | |
cd324edc JW |
7187 | if (parent_effective > siblings_protected && |
7188 | parent_usage > siblings_protected && | |
7189 | usage > protected) { | |
8a931f80 JW |
7190 | unsigned long unclaimed; |
7191 | ||
7192 | unclaimed = parent_effective - siblings_protected; | |
7193 | unclaimed *= usage - protected; | |
7194 | unclaimed /= parent_usage - siblings_protected; | |
7195 | ||
7196 | ep += unclaimed; | |
7197 | } | |
7198 | ||
7199 | return ep; | |
bc50bcc6 JW |
7200 | } |
7201 | ||
241994ed | 7202 | /** |
05395718 | 7203 | * mem_cgroup_calculate_protection - check if memory consumption is in the normal range |
34c81057 | 7204 | * @root: the top ancestor of the sub-tree being checked |
241994ed JW |
7205 | * @memcg: the memory cgroup to check |
7206 | * | |
23067153 RG |
7207 | * WARNING: This function is not stateless! It can only be used as part |
7208 | * of a top-down tree iteration, not for isolated queries. | |
241994ed | 7209 | */ |
45c7f7e1 CD |
7210 | void mem_cgroup_calculate_protection(struct mem_cgroup *root, |
7211 | struct mem_cgroup *memcg) | |
241994ed | 7212 | { |
8a931f80 | 7213 | unsigned long usage, parent_usage; |
23067153 RG |
7214 | struct mem_cgroup *parent; |
7215 | ||
241994ed | 7216 | if (mem_cgroup_disabled()) |
45c7f7e1 | 7217 | return; |
241994ed | 7218 | |
34c81057 SC |
7219 | if (!root) |
7220 | root = root_mem_cgroup; | |
22f7496f YS |
7221 | |
7222 | /* | |
7223 | * Effective values of the reclaim targets are ignored so they | |
7224 | * can be stale. Have a look at mem_cgroup_protection for more | |
7225 | * details. | |
7226 | * TODO: calculation should be more robust so that we do not need | |
7227 | * that special casing. | |
7228 | */ | |
34c81057 | 7229 | if (memcg == root) |
45c7f7e1 | 7230 | return; |
241994ed | 7231 | |
23067153 | 7232 | usage = page_counter_read(&memcg->memory); |
bf8d5d52 | 7233 | if (!usage) |
45c7f7e1 | 7234 | return; |
bf8d5d52 | 7235 | |
bf8d5d52 | 7236 | parent = parent_mem_cgroup(memcg); |
df2a4196 | 7237 | |
bc50bcc6 | 7238 | if (parent == root) { |
c3d53200 | 7239 | memcg->memory.emin = READ_ONCE(memcg->memory.min); |
03960e33 | 7240 | memcg->memory.elow = READ_ONCE(memcg->memory.low); |
45c7f7e1 | 7241 | return; |
bf8d5d52 RG |
7242 | } |
7243 | ||
8a931f80 JW |
7244 | parent_usage = page_counter_read(&parent->memory); |
7245 | ||
b3a7822e | 7246 | WRITE_ONCE(memcg->memory.emin, effective_protection(usage, parent_usage, |
c3d53200 CD |
7247 | READ_ONCE(memcg->memory.min), |
7248 | READ_ONCE(parent->memory.emin), | |
b3a7822e | 7249 | atomic_long_read(&parent->memory.children_min_usage))); |
23067153 | 7250 | |
b3a7822e | 7251 | WRITE_ONCE(memcg->memory.elow, effective_protection(usage, parent_usage, |
03960e33 CD |
7252 | READ_ONCE(memcg->memory.low), |
7253 | READ_ONCE(parent->memory.elow), | |
b3a7822e | 7254 | atomic_long_read(&parent->memory.children_low_usage))); |
241994ed JW |
7255 | } |
7256 | ||
8f425e4e MWO |
7257 | static int charge_memcg(struct folio *folio, struct mem_cgroup *memcg, |
7258 | gfp_t gfp) | |
0add0c77 | 7259 | { |
0add0c77 SB |
7260 | int ret; |
7261 | ||
4b569387 | 7262 | ret = try_charge(memcg, gfp, folio_nr_pages(folio)); |
0add0c77 SB |
7263 | if (ret) |
7264 | goto out; | |
7265 | ||
4b569387 | 7266 | mem_cgroup_commit_charge(folio, memcg); |
0add0c77 SB |
7267 | out: |
7268 | return ret; | |
7269 | } | |
7270 | ||
8f425e4e | 7271 | int __mem_cgroup_charge(struct folio *folio, struct mm_struct *mm, gfp_t gfp) |
00501b53 | 7272 | { |
0add0c77 SB |
7273 | struct mem_cgroup *memcg; |
7274 | int ret; | |
00501b53 | 7275 | |
0add0c77 | 7276 | memcg = get_mem_cgroup_from_mm(mm); |
8f425e4e | 7277 | ret = charge_memcg(folio, memcg, gfp); |
0add0c77 | 7278 | css_put(&memcg->css); |
2d1c4980 | 7279 | |
0add0c77 SB |
7280 | return ret; |
7281 | } | |
e993d905 | 7282 | |
8cba9576 NP |
7283 | /** |
7284 | * mem_cgroup_hugetlb_try_charge - try to charge the memcg for a hugetlb folio | |
7285 | * @memcg: memcg to charge. | |
7286 | * @gfp: reclaim mode. | |
7287 | * @nr_pages: number of pages to charge. | |
7288 | * | |
7289 | * This function is called when allocating a huge page folio to determine if | |
7290 | * the memcg has the capacity for it. It does not commit the charge yet, | |
7291 | * as the hugetlb folio itself has not been obtained from the hugetlb pool. | |
7292 | * | |
7293 | * Once we have obtained the hugetlb folio, we can call | |
7294 | * mem_cgroup_commit_charge() to commit the charge. If we fail to obtain the | |
7295 | * folio, we should instead call mem_cgroup_cancel_charge() to undo the effect | |
7296 | * of try_charge(). | |
7297 | * | |
7298 | * Returns 0 on success. Otherwise, an error code is returned. | |
7299 | */ | |
7300 | int mem_cgroup_hugetlb_try_charge(struct mem_cgroup *memcg, gfp_t gfp, | |
7301 | long nr_pages) | |
7302 | { | |
7303 | /* | |
7304 | * If hugetlb memcg charging is not enabled, do not fail hugetlb allocation, | |
7305 | * but do not attempt to commit charge later (or cancel on error) either. | |
7306 | */ | |
7307 | if (mem_cgroup_disabled() || !memcg || | |
7308 | !cgroup_subsys_on_dfl(memory_cgrp_subsys) || | |
7309 | !(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING)) | |
7310 | return -EOPNOTSUPP; | |
7311 | ||
7312 | if (try_charge(memcg, gfp, nr_pages)) | |
7313 | return -ENOMEM; | |
7314 | ||
7315 | return 0; | |
7316 | } | |
7317 | ||
0add0c77 | 7318 | /** |
65995918 MWO |
7319 | * mem_cgroup_swapin_charge_folio - Charge a newly allocated folio for swapin. |
7320 | * @folio: folio to charge. | |
0add0c77 SB |
7321 | * @mm: mm context of the victim |
7322 | * @gfp: reclaim mode | |
65995918 | 7323 | * @entry: swap entry for which the folio is allocated |
0add0c77 | 7324 | * |
65995918 MWO |
7325 | * This function charges a folio allocated for swapin. Please call this before |
7326 | * adding the folio to the swapcache. | |
0add0c77 SB |
7327 | * |
7328 | * Returns 0 on success. Otherwise, an error code is returned. | |
7329 | */ | |
65995918 | 7330 | int mem_cgroup_swapin_charge_folio(struct folio *folio, struct mm_struct *mm, |
0add0c77 SB |
7331 | gfp_t gfp, swp_entry_t entry) |
7332 | { | |
7333 | struct mem_cgroup *memcg; | |
7334 | unsigned short id; | |
7335 | int ret; | |
00501b53 | 7336 | |
0add0c77 SB |
7337 | if (mem_cgroup_disabled()) |
7338 | return 0; | |
00501b53 | 7339 | |
0add0c77 SB |
7340 | id = lookup_swap_cgroup_id(entry); |
7341 | rcu_read_lock(); | |
7342 | memcg = mem_cgroup_from_id(id); | |
7343 | if (!memcg || !css_tryget_online(&memcg->css)) | |
7344 | memcg = get_mem_cgroup_from_mm(mm); | |
7345 | rcu_read_unlock(); | |
00501b53 | 7346 | |
8f425e4e | 7347 | ret = charge_memcg(folio, memcg, gfp); |
6abb5a86 | 7348 | |
0add0c77 SB |
7349 | css_put(&memcg->css); |
7350 | return ret; | |
7351 | } | |
00501b53 | 7352 | |
0add0c77 SB |
7353 | /* |
7354 | * mem_cgroup_swapin_uncharge_swap - uncharge swap slot | |
7355 | * @entry: swap entry for which the page is charged | |
7356 | * | |
7357 | * Call this function after successfully adding the charged page to swapcache. | |
7358 | * | |
7359 | * Note: This function assumes the page for which swap slot is being uncharged | |
7360 | * is order 0 page. | |
7361 | */ | |
7362 | void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry) | |
7363 | { | |
cae3af62 MS |
7364 | /* |
7365 | * Cgroup1's unified memory+swap counter has been charged with the | |
7366 | * new swapcache page, finish the transfer by uncharging the swap | |
7367 | * slot. The swap slot would also get uncharged when it dies, but | |
7368 | * it can stick around indefinitely and we'd count the page twice | |
7369 | * the entire time. | |
7370 | * | |
7371 | * Cgroup2 has separate resource counters for memory and swap, | |
7372 | * so this is a non-issue here. Memory and swap charge lifetimes | |
7373 | * correspond 1:1 to page and swap slot lifetimes: we charge the | |
7374 | * page to memory here, and uncharge swap when the slot is freed. | |
7375 | */ | |
0add0c77 | 7376 | if (!mem_cgroup_disabled() && do_memsw_account()) { |
00501b53 JW |
7377 | /* |
7378 | * The swap entry might not get freed for a long time, | |
7379 | * let's not wait for it. The page already received a | |
7380 | * memory+swap charge, drop the swap entry duplicate. | |
7381 | */ | |
0add0c77 | 7382 | mem_cgroup_uncharge_swap(entry, 1); |
00501b53 | 7383 | } |
3fea5a49 JW |
7384 | } |
7385 | ||
a9d5adee JG |
7386 | struct uncharge_gather { |
7387 | struct mem_cgroup *memcg; | |
b4e0b68f | 7388 | unsigned long nr_memory; |
a9d5adee | 7389 | unsigned long pgpgout; |
a9d5adee | 7390 | unsigned long nr_kmem; |
8e88bd2d | 7391 | int nid; |
a9d5adee JG |
7392 | }; |
7393 | ||
7394 | static inline void uncharge_gather_clear(struct uncharge_gather *ug) | |
747db954 | 7395 | { |
a9d5adee JG |
7396 | memset(ug, 0, sizeof(*ug)); |
7397 | } | |
7398 | ||
7399 | static void uncharge_batch(const struct uncharge_gather *ug) | |
7400 | { | |
747db954 JW |
7401 | unsigned long flags; |
7402 | ||
b4e0b68f MS |
7403 | if (ug->nr_memory) { |
7404 | page_counter_uncharge(&ug->memcg->memory, ug->nr_memory); | |
7941d214 | 7405 | if (do_memsw_account()) |
b4e0b68f | 7406 | page_counter_uncharge(&ug->memcg->memsw, ug->nr_memory); |
a8c49af3 YA |
7407 | if (ug->nr_kmem) |
7408 | memcg_account_kmem(ug->memcg, -ug->nr_kmem); | |
a9d5adee | 7409 | memcg_oom_recover(ug->memcg); |
ce00a967 | 7410 | } |
747db954 JW |
7411 | |
7412 | local_irq_save(flags); | |
c9019e9b | 7413 | __count_memcg_events(ug->memcg, PGPGOUT, ug->pgpgout); |
b4e0b68f | 7414 | __this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, ug->nr_memory); |
8e88bd2d | 7415 | memcg_check_events(ug->memcg, ug->nid); |
747db954 | 7416 | local_irq_restore(flags); |
f1796544 | 7417 | |
c4ed6ebf | 7418 | /* drop reference from uncharge_folio */ |
f1796544 | 7419 | css_put(&ug->memcg->css); |
a9d5adee JG |
7420 | } |
7421 | ||
c4ed6ebf | 7422 | static void uncharge_folio(struct folio *folio, struct uncharge_gather *ug) |
a9d5adee | 7423 | { |
c4ed6ebf | 7424 | long nr_pages; |
b4e0b68f MS |
7425 | struct mem_cgroup *memcg; |
7426 | struct obj_cgroup *objcg; | |
9f762dbe | 7427 | |
c4ed6ebf | 7428 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
a9d5adee | 7429 | |
a9d5adee JG |
7430 | /* |
7431 | * Nobody should be changing or seriously looking at | |
c4ed6ebf MWO |
7432 | * folio memcg or objcg at this point, we have fully |
7433 | * exclusive access to the folio. | |
a9d5adee | 7434 | */ |
fead2b86 | 7435 | if (folio_memcg_kmem(folio)) { |
1b7e4464 | 7436 | objcg = __folio_objcg(folio); |
b4e0b68f MS |
7437 | /* |
7438 | * This get matches the put at the end of the function and | |
7439 | * kmem pages do not hold memcg references anymore. | |
7440 | */ | |
7441 | memcg = get_mem_cgroup_from_objcg(objcg); | |
7442 | } else { | |
1b7e4464 | 7443 | memcg = __folio_memcg(folio); |
b4e0b68f | 7444 | } |
a9d5adee | 7445 | |
b4e0b68f MS |
7446 | if (!memcg) |
7447 | return; | |
7448 | ||
7449 | if (ug->memcg != memcg) { | |
a9d5adee JG |
7450 | if (ug->memcg) { |
7451 | uncharge_batch(ug); | |
7452 | uncharge_gather_clear(ug); | |
7453 | } | |
b4e0b68f | 7454 | ug->memcg = memcg; |
c4ed6ebf | 7455 | ug->nid = folio_nid(folio); |
f1796544 MH |
7456 | |
7457 | /* pairs with css_put in uncharge_batch */ | |
b4e0b68f | 7458 | css_get(&memcg->css); |
a9d5adee JG |
7459 | } |
7460 | ||
c4ed6ebf | 7461 | nr_pages = folio_nr_pages(folio); |
a9d5adee | 7462 | |
fead2b86 | 7463 | if (folio_memcg_kmem(folio)) { |
b4e0b68f | 7464 | ug->nr_memory += nr_pages; |
9f762dbe | 7465 | ug->nr_kmem += nr_pages; |
b4e0b68f | 7466 | |
c4ed6ebf | 7467 | folio->memcg_data = 0; |
b4e0b68f MS |
7468 | obj_cgroup_put(objcg); |
7469 | } else { | |
7470 | /* LRU pages aren't accounted at the root level */ | |
7471 | if (!mem_cgroup_is_root(memcg)) | |
7472 | ug->nr_memory += nr_pages; | |
18b2db3b | 7473 | ug->pgpgout++; |
a9d5adee | 7474 | |
c4ed6ebf | 7475 | folio->memcg_data = 0; |
b4e0b68f MS |
7476 | } |
7477 | ||
7478 | css_put(&memcg->css); | |
747db954 JW |
7479 | } |
7480 | ||
bbc6b703 | 7481 | void __mem_cgroup_uncharge(struct folio *folio) |
0a31bc97 | 7482 | { |
a9d5adee JG |
7483 | struct uncharge_gather ug; |
7484 | ||
bbc6b703 MWO |
7485 | /* Don't touch folio->lru of any random page, pre-check: */ |
7486 | if (!folio_memcg(folio)) | |
0a31bc97 JW |
7487 | return; |
7488 | ||
a9d5adee | 7489 | uncharge_gather_clear(&ug); |
bbc6b703 | 7490 | uncharge_folio(folio, &ug); |
a9d5adee | 7491 | uncharge_batch(&ug); |
747db954 | 7492 | } |
0a31bc97 | 7493 | |
747db954 | 7494 | /** |
2c8d8f97 | 7495 | * __mem_cgroup_uncharge_list - uncharge a list of page |
747db954 JW |
7496 | * @page_list: list of pages to uncharge |
7497 | * | |
7498 | * Uncharge a list of pages previously charged with | |
2c8d8f97 | 7499 | * __mem_cgroup_charge(). |
747db954 | 7500 | */ |
2c8d8f97 | 7501 | void __mem_cgroup_uncharge_list(struct list_head *page_list) |
747db954 | 7502 | { |
c41a40b6 | 7503 | struct uncharge_gather ug; |
c4ed6ebf | 7504 | struct folio *folio; |
c41a40b6 | 7505 | |
c41a40b6 | 7506 | uncharge_gather_clear(&ug); |
c4ed6ebf MWO |
7507 | list_for_each_entry(folio, page_list, lru) |
7508 | uncharge_folio(folio, &ug); | |
c41a40b6 MS |
7509 | if (ug.memcg) |
7510 | uncharge_batch(&ug); | |
0a31bc97 JW |
7511 | } |
7512 | ||
7513 | /** | |
85ce2c51 | 7514 | * mem_cgroup_replace_folio - Charge a folio's replacement. |
d21bba2b MWO |
7515 | * @old: Currently circulating folio. |
7516 | * @new: Replacement folio. | |
0a31bc97 | 7517 | * |
d21bba2b | 7518 | * Charge @new as a replacement folio for @old. @old will |
85ce2c51 NP |
7519 | * be uncharged upon free. This is only used by the page cache |
7520 | * (in replace_page_cache_folio()). | |
0a31bc97 | 7521 | * |
d21bba2b | 7522 | * Both folios must be locked, @new->mapping must be set up. |
0a31bc97 | 7523 | */ |
85ce2c51 | 7524 | void mem_cgroup_replace_folio(struct folio *old, struct folio *new) |
0a31bc97 | 7525 | { |
29833315 | 7526 | struct mem_cgroup *memcg; |
d21bba2b | 7527 | long nr_pages = folio_nr_pages(new); |
d93c4130 | 7528 | unsigned long flags; |
0a31bc97 | 7529 | |
d21bba2b MWO |
7530 | VM_BUG_ON_FOLIO(!folio_test_locked(old), old); |
7531 | VM_BUG_ON_FOLIO(!folio_test_locked(new), new); | |
7532 | VM_BUG_ON_FOLIO(folio_test_anon(old) != folio_test_anon(new), new); | |
7533 | VM_BUG_ON_FOLIO(folio_nr_pages(old) != nr_pages, new); | |
0a31bc97 JW |
7534 | |
7535 | if (mem_cgroup_disabled()) | |
7536 | return; | |
7537 | ||
d21bba2b MWO |
7538 | /* Page cache replacement: new folio already charged? */ |
7539 | if (folio_memcg(new)) | |
0a31bc97 JW |
7540 | return; |
7541 | ||
d21bba2b MWO |
7542 | memcg = folio_memcg(old); |
7543 | VM_WARN_ON_ONCE_FOLIO(!memcg, old); | |
29833315 | 7544 | if (!memcg) |
0a31bc97 JW |
7545 | return; |
7546 | ||
44b7a8d3 | 7547 | /* Force-charge the new page. The old one will be freed soon */ |
8dc87c7d MS |
7548 | if (!mem_cgroup_is_root(memcg)) { |
7549 | page_counter_charge(&memcg->memory, nr_pages); | |
7550 | if (do_memsw_account()) | |
7551 | page_counter_charge(&memcg->memsw, nr_pages); | |
7552 | } | |
0a31bc97 | 7553 | |
1a3e1f40 | 7554 | css_get(&memcg->css); |
d21bba2b | 7555 | commit_charge(new, memcg); |
44b7a8d3 | 7556 | |
d93c4130 | 7557 | local_irq_save(flags); |
6e0110c2 | 7558 | mem_cgroup_charge_statistics(memcg, nr_pages); |
d21bba2b | 7559 | memcg_check_events(memcg, folio_nid(new)); |
d93c4130 | 7560 | local_irq_restore(flags); |
0a31bc97 JW |
7561 | } |
7562 | ||
85ce2c51 NP |
7563 | /** |
7564 | * mem_cgroup_migrate - Transfer the memcg data from the old to the new folio. | |
7565 | * @old: Currently circulating folio. | |
7566 | * @new: Replacement folio. | |
7567 | * | |
7568 | * Transfer the memcg data from the old folio to the new folio for migration. | |
7569 | * The old folio's data info will be cleared. Note that the memory counters | |
7570 | * will remain unchanged throughout the process. | |
7571 | * | |
7572 | * Both folios must be locked, @new->mapping must be set up. | |
7573 | */ | |
7574 | void mem_cgroup_migrate(struct folio *old, struct folio *new) | |
7575 | { | |
7576 | struct mem_cgroup *memcg; | |
7577 | ||
7578 | VM_BUG_ON_FOLIO(!folio_test_locked(old), old); | |
7579 | VM_BUG_ON_FOLIO(!folio_test_locked(new), new); | |
7580 | VM_BUG_ON_FOLIO(folio_test_anon(old) != folio_test_anon(new), new); | |
7581 | VM_BUG_ON_FOLIO(folio_nr_pages(old) != folio_nr_pages(new), new); | |
7582 | ||
7583 | if (mem_cgroup_disabled()) | |
7584 | return; | |
7585 | ||
7586 | memcg = folio_memcg(old); | |
8cba9576 NP |
7587 | /* |
7588 | * Note that it is normal to see !memcg for a hugetlb folio. | |
7589 | * For e.g, itt could have been allocated when memory_hugetlb_accounting | |
7590 | * was not selected. | |
7591 | */ | |
7592 | VM_WARN_ON_ONCE_FOLIO(!folio_test_hugetlb(old) && !memcg, old); | |
85ce2c51 NP |
7593 | if (!memcg) |
7594 | return; | |
7595 | ||
7596 | /* Transfer the charge and the css ref */ | |
7597 | commit_charge(new, memcg); | |
9bcef597 BW |
7598 | /* |
7599 | * If the old folio is a large folio and is in the split queue, it needs | |
7600 | * to be removed from the split queue now, in case getting an incorrect | |
7601 | * split queue in destroy_large_folio() after the memcg of the old folio | |
7602 | * is cleared. | |
7603 | * | |
7604 | * In addition, the old folio is about to be freed after migration, so | |
7605 | * removing from the split queue a bit earlier seems reasonable. | |
7606 | */ | |
7607 | if (folio_test_large(old) && folio_test_large_rmappable(old)) | |
7608 | folio_undo_large_rmappable(old); | |
85ce2c51 NP |
7609 | old->memcg_data = 0; |
7610 | } | |
7611 | ||
ef12947c | 7612 | DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key); |
11092087 JW |
7613 | EXPORT_SYMBOL(memcg_sockets_enabled_key); |
7614 | ||
2d758073 | 7615 | void mem_cgroup_sk_alloc(struct sock *sk) |
11092087 JW |
7616 | { |
7617 | struct mem_cgroup *memcg; | |
7618 | ||
2d758073 JW |
7619 | if (!mem_cgroup_sockets_enabled) |
7620 | return; | |
7621 | ||
e876ecc6 | 7622 | /* Do not associate the sock with unrelated interrupted task's memcg. */ |
086f694a | 7623 | if (!in_task()) |
e876ecc6 SB |
7624 | return; |
7625 | ||
11092087 JW |
7626 | rcu_read_lock(); |
7627 | memcg = mem_cgroup_from_task(current); | |
7848ed62 | 7628 | if (mem_cgroup_is_root(memcg)) |
f7e1cb6e | 7629 | goto out; |
0db15298 | 7630 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcpmem_active) |
f7e1cb6e | 7631 | goto out; |
8965aa28 | 7632 | if (css_tryget(&memcg->css)) |
11092087 | 7633 | sk->sk_memcg = memcg; |
f7e1cb6e | 7634 | out: |
11092087 JW |
7635 | rcu_read_unlock(); |
7636 | } | |
11092087 | 7637 | |
2d758073 | 7638 | void mem_cgroup_sk_free(struct sock *sk) |
11092087 | 7639 | { |
2d758073 JW |
7640 | if (sk->sk_memcg) |
7641 | css_put(&sk->sk_memcg->css); | |
11092087 JW |
7642 | } |
7643 | ||
7644 | /** | |
7645 | * mem_cgroup_charge_skmem - charge socket memory | |
7646 | * @memcg: memcg to charge | |
7647 | * @nr_pages: number of pages to charge | |
4b1327be | 7648 | * @gfp_mask: reclaim mode |
11092087 JW |
7649 | * |
7650 | * Charges @nr_pages to @memcg. Returns %true if the charge fit within | |
4b1327be | 7651 | * @memcg's configured limit, %false if it doesn't. |
11092087 | 7652 | */ |
4b1327be WW |
7653 | bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages, |
7654 | gfp_t gfp_mask) | |
11092087 | 7655 | { |
f7e1cb6e | 7656 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 7657 | struct page_counter *fail; |
f7e1cb6e | 7658 | |
0db15298 JW |
7659 | if (page_counter_try_charge(&memcg->tcpmem, nr_pages, &fail)) { |
7660 | memcg->tcpmem_pressure = 0; | |
f7e1cb6e JW |
7661 | return true; |
7662 | } | |
0db15298 | 7663 | memcg->tcpmem_pressure = 1; |
4b1327be WW |
7664 | if (gfp_mask & __GFP_NOFAIL) { |
7665 | page_counter_charge(&memcg->tcpmem, nr_pages); | |
7666 | return true; | |
7667 | } | |
f7e1cb6e | 7668 | return false; |
11092087 | 7669 | } |
d886f4e4 | 7670 | |
4b1327be WW |
7671 | if (try_charge(memcg, gfp_mask, nr_pages) == 0) { |
7672 | mod_memcg_state(memcg, MEMCG_SOCK, nr_pages); | |
f7e1cb6e | 7673 | return true; |
4b1327be | 7674 | } |
f7e1cb6e | 7675 | |
11092087 JW |
7676 | return false; |
7677 | } | |
7678 | ||
7679 | /** | |
7680 | * mem_cgroup_uncharge_skmem - uncharge socket memory | |
b7701a5f MR |
7681 | * @memcg: memcg to uncharge |
7682 | * @nr_pages: number of pages to uncharge | |
11092087 JW |
7683 | */ |
7684 | void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) | |
7685 | { | |
f7e1cb6e | 7686 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 7687 | page_counter_uncharge(&memcg->tcpmem, nr_pages); |
f7e1cb6e JW |
7688 | return; |
7689 | } | |
d886f4e4 | 7690 | |
c9019e9b | 7691 | mod_memcg_state(memcg, MEMCG_SOCK, -nr_pages); |
b2807f07 | 7692 | |
475d0487 | 7693 | refill_stock(memcg, nr_pages); |
11092087 JW |
7694 | } |
7695 | ||
f7e1cb6e JW |
7696 | static int __init cgroup_memory(char *s) |
7697 | { | |
7698 | char *token; | |
7699 | ||
7700 | while ((token = strsep(&s, ",")) != NULL) { | |
7701 | if (!*token) | |
7702 | continue; | |
7703 | if (!strcmp(token, "nosocket")) | |
7704 | cgroup_memory_nosocket = true; | |
04823c83 VD |
7705 | if (!strcmp(token, "nokmem")) |
7706 | cgroup_memory_nokmem = true; | |
b6c1a8af YS |
7707 | if (!strcmp(token, "nobpf")) |
7708 | cgroup_memory_nobpf = true; | |
f7e1cb6e | 7709 | } |
460a79e1 | 7710 | return 1; |
f7e1cb6e JW |
7711 | } |
7712 | __setup("cgroup.memory=", cgroup_memory); | |
11092087 | 7713 | |
2d11085e | 7714 | /* |
1081312f MH |
7715 | * subsys_initcall() for memory controller. |
7716 | * | |
308167fc SAS |
7717 | * Some parts like memcg_hotplug_cpu_dead() have to be initialized from this |
7718 | * context because of lock dependencies (cgroup_lock -> cpu hotplug) but | |
7719 | * basically everything that doesn't depend on a specific mem_cgroup structure | |
7720 | * should be initialized from here. | |
2d11085e MH |
7721 | */ |
7722 | static int __init mem_cgroup_init(void) | |
7723 | { | |
95a045f6 JW |
7724 | int cpu, node; |
7725 | ||
f3344adf MS |
7726 | /* |
7727 | * Currently s32 type (can refer to struct batched_lruvec_stat) is | |
7728 | * used for per-memcg-per-cpu caching of per-node statistics. In order | |
7729 | * to work fine, we should make sure that the overfill threshold can't | |
7730 | * exceed S32_MAX / PAGE_SIZE. | |
7731 | */ | |
7732 | BUILD_BUG_ON(MEMCG_CHARGE_BATCH > S32_MAX / PAGE_SIZE); | |
7733 | ||
308167fc SAS |
7734 | cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL, |
7735 | memcg_hotplug_cpu_dead); | |
95a045f6 JW |
7736 | |
7737 | for_each_possible_cpu(cpu) | |
7738 | INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work, | |
7739 | drain_local_stock); | |
7740 | ||
7741 | for_each_node(node) { | |
7742 | struct mem_cgroup_tree_per_node *rtpn; | |
95a045f6 | 7743 | |
91f0dcce | 7744 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, node); |
95a045f6 | 7745 | |
ef8f2327 | 7746 | rtpn->rb_root = RB_ROOT; |
fa90b2fd | 7747 | rtpn->rb_rightmost = NULL; |
ef8f2327 | 7748 | spin_lock_init(&rtpn->lock); |
95a045f6 JW |
7749 | soft_limit_tree.rb_tree_per_node[node] = rtpn; |
7750 | } | |
7751 | ||
2d11085e MH |
7752 | return 0; |
7753 | } | |
7754 | subsys_initcall(mem_cgroup_init); | |
21afa38e | 7755 | |
e55b9f96 | 7756 | #ifdef CONFIG_SWAP |
358c07fc AB |
7757 | static struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg) |
7758 | { | |
1c2d479a | 7759 | while (!refcount_inc_not_zero(&memcg->id.ref)) { |
358c07fc AB |
7760 | /* |
7761 | * The root cgroup cannot be destroyed, so it's refcount must | |
7762 | * always be >= 1. | |
7763 | */ | |
7848ed62 | 7764 | if (WARN_ON_ONCE(mem_cgroup_is_root(memcg))) { |
358c07fc AB |
7765 | VM_BUG_ON(1); |
7766 | break; | |
7767 | } | |
7768 | memcg = parent_mem_cgroup(memcg); | |
7769 | if (!memcg) | |
7770 | memcg = root_mem_cgroup; | |
7771 | } | |
7772 | return memcg; | |
7773 | } | |
7774 | ||
21afa38e JW |
7775 | /** |
7776 | * mem_cgroup_swapout - transfer a memsw charge to swap | |
3ecb0087 | 7777 | * @folio: folio whose memsw charge to transfer |
21afa38e JW |
7778 | * @entry: swap entry to move the charge to |
7779 | * | |
3ecb0087 | 7780 | * Transfer the memsw charge of @folio to @entry. |
21afa38e | 7781 | */ |
3ecb0087 | 7782 | void mem_cgroup_swapout(struct folio *folio, swp_entry_t entry) |
21afa38e | 7783 | { |
1f47b61f | 7784 | struct mem_cgroup *memcg, *swap_memcg; |
d6810d73 | 7785 | unsigned int nr_entries; |
21afa38e JW |
7786 | unsigned short oldid; |
7787 | ||
3ecb0087 MWO |
7788 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
7789 | VM_BUG_ON_FOLIO(folio_ref_count(folio), folio); | |
21afa38e | 7790 | |
76358ab5 AS |
7791 | if (mem_cgroup_disabled()) |
7792 | return; | |
7793 | ||
b94c4e94 | 7794 | if (!do_memsw_account()) |
21afa38e JW |
7795 | return; |
7796 | ||
3ecb0087 | 7797 | memcg = folio_memcg(folio); |
21afa38e | 7798 | |
3ecb0087 | 7799 | VM_WARN_ON_ONCE_FOLIO(!memcg, folio); |
21afa38e JW |
7800 | if (!memcg) |
7801 | return; | |
7802 | ||
1f47b61f VD |
7803 | /* |
7804 | * In case the memcg owning these pages has been offlined and doesn't | |
7805 | * have an ID allocated to it anymore, charge the closest online | |
7806 | * ancestor for the swap instead and transfer the memory+swap charge. | |
7807 | */ | |
7808 | swap_memcg = mem_cgroup_id_get_online(memcg); | |
3ecb0087 | 7809 | nr_entries = folio_nr_pages(folio); |
d6810d73 HY |
7810 | /* Get references for the tail pages, too */ |
7811 | if (nr_entries > 1) | |
7812 | mem_cgroup_id_get_many(swap_memcg, nr_entries - 1); | |
7813 | oldid = swap_cgroup_record(entry, mem_cgroup_id(swap_memcg), | |
7814 | nr_entries); | |
3ecb0087 | 7815 | VM_BUG_ON_FOLIO(oldid, folio); |
c9019e9b | 7816 | mod_memcg_state(swap_memcg, MEMCG_SWAP, nr_entries); |
21afa38e | 7817 | |
3ecb0087 | 7818 | folio->memcg_data = 0; |
21afa38e JW |
7819 | |
7820 | if (!mem_cgroup_is_root(memcg)) | |
d6810d73 | 7821 | page_counter_uncharge(&memcg->memory, nr_entries); |
21afa38e | 7822 | |
b25806dc | 7823 | if (memcg != swap_memcg) { |
1f47b61f | 7824 | if (!mem_cgroup_is_root(swap_memcg)) |
d6810d73 HY |
7825 | page_counter_charge(&swap_memcg->memsw, nr_entries); |
7826 | page_counter_uncharge(&memcg->memsw, nr_entries); | |
1f47b61f VD |
7827 | } |
7828 | ||
ce9ce665 SAS |
7829 | /* |
7830 | * Interrupts should be disabled here because the caller holds the | |
b93b0163 | 7831 | * i_pages lock which is taken with interrupts-off. It is |
ce9ce665 | 7832 | * important here to have the interrupts disabled because it is the |
b93b0163 | 7833 | * only synchronisation we have for updating the per-CPU variables. |
ce9ce665 | 7834 | */ |
be3e67b5 | 7835 | memcg_stats_lock(); |
6e0110c2 | 7836 | mem_cgroup_charge_statistics(memcg, -nr_entries); |
be3e67b5 | 7837 | memcg_stats_unlock(); |
3ecb0087 | 7838 | memcg_check_events(memcg, folio_nid(folio)); |
73f576c0 | 7839 | |
1a3e1f40 | 7840 | css_put(&memcg->css); |
21afa38e JW |
7841 | } |
7842 | ||
38d8b4e6 | 7843 | /** |
e2e3fdc7 MWO |
7844 | * __mem_cgroup_try_charge_swap - try charging swap space for a folio |
7845 | * @folio: folio being added to swap | |
37e84351 VD |
7846 | * @entry: swap entry to charge |
7847 | * | |
e2e3fdc7 | 7848 | * Try to charge @folio's memcg for the swap space at @entry. |
37e84351 VD |
7849 | * |
7850 | * Returns 0 on success, -ENOMEM on failure. | |
7851 | */ | |
e2e3fdc7 | 7852 | int __mem_cgroup_try_charge_swap(struct folio *folio, swp_entry_t entry) |
37e84351 | 7853 | { |
e2e3fdc7 | 7854 | unsigned int nr_pages = folio_nr_pages(folio); |
37e84351 | 7855 | struct page_counter *counter; |
38d8b4e6 | 7856 | struct mem_cgroup *memcg; |
37e84351 VD |
7857 | unsigned short oldid; |
7858 | ||
b94c4e94 | 7859 | if (do_memsw_account()) |
37e84351 VD |
7860 | return 0; |
7861 | ||
e2e3fdc7 | 7862 | memcg = folio_memcg(folio); |
37e84351 | 7863 | |
e2e3fdc7 | 7864 | VM_WARN_ON_ONCE_FOLIO(!memcg, folio); |
37e84351 VD |
7865 | if (!memcg) |
7866 | return 0; | |
7867 | ||
f3a53a3a TH |
7868 | if (!entry.val) { |
7869 | memcg_memory_event(memcg, MEMCG_SWAP_FAIL); | |
bb98f2c5 | 7870 | return 0; |
f3a53a3a | 7871 | } |
bb98f2c5 | 7872 | |
1f47b61f VD |
7873 | memcg = mem_cgroup_id_get_online(memcg); |
7874 | ||
b25806dc | 7875 | if (!mem_cgroup_is_root(memcg) && |
38d8b4e6 | 7876 | !page_counter_try_charge(&memcg->swap, nr_pages, &counter)) { |
f3a53a3a TH |
7877 | memcg_memory_event(memcg, MEMCG_SWAP_MAX); |
7878 | memcg_memory_event(memcg, MEMCG_SWAP_FAIL); | |
1f47b61f | 7879 | mem_cgroup_id_put(memcg); |
37e84351 | 7880 | return -ENOMEM; |
1f47b61f | 7881 | } |
37e84351 | 7882 | |
38d8b4e6 HY |
7883 | /* Get references for the tail pages, too */ |
7884 | if (nr_pages > 1) | |
7885 | mem_cgroup_id_get_many(memcg, nr_pages - 1); | |
7886 | oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg), nr_pages); | |
e2e3fdc7 | 7887 | VM_BUG_ON_FOLIO(oldid, folio); |
c9019e9b | 7888 | mod_memcg_state(memcg, MEMCG_SWAP, nr_pages); |
37e84351 | 7889 | |
37e84351 VD |
7890 | return 0; |
7891 | } | |
7892 | ||
21afa38e | 7893 | /** |
01c4b28c | 7894 | * __mem_cgroup_uncharge_swap - uncharge swap space |
21afa38e | 7895 | * @entry: swap entry to uncharge |
38d8b4e6 | 7896 | * @nr_pages: the amount of swap space to uncharge |
21afa38e | 7897 | */ |
01c4b28c | 7898 | void __mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages) |
21afa38e JW |
7899 | { |
7900 | struct mem_cgroup *memcg; | |
7901 | unsigned short id; | |
7902 | ||
38d8b4e6 | 7903 | id = swap_cgroup_record(entry, 0, nr_pages); |
21afa38e | 7904 | rcu_read_lock(); |
adbe427b | 7905 | memcg = mem_cgroup_from_id(id); |
21afa38e | 7906 | if (memcg) { |
b25806dc | 7907 | if (!mem_cgroup_is_root(memcg)) { |
b94c4e94 | 7908 | if (do_memsw_account()) |
38d8b4e6 | 7909 | page_counter_uncharge(&memcg->memsw, nr_pages); |
b94c4e94 JW |
7910 | else |
7911 | page_counter_uncharge(&memcg->swap, nr_pages); | |
37e84351 | 7912 | } |
c9019e9b | 7913 | mod_memcg_state(memcg, MEMCG_SWAP, -nr_pages); |
38d8b4e6 | 7914 | mem_cgroup_id_put_many(memcg, nr_pages); |
21afa38e JW |
7915 | } |
7916 | rcu_read_unlock(); | |
7917 | } | |
7918 | ||
d8b38438 VD |
7919 | long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg) |
7920 | { | |
7921 | long nr_swap_pages = get_nr_swap_pages(); | |
7922 | ||
b25806dc | 7923 | if (mem_cgroup_disabled() || do_memsw_account()) |
d8b38438 | 7924 | return nr_swap_pages; |
7848ed62 | 7925 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) |
d8b38438 | 7926 | nr_swap_pages = min_t(long, nr_swap_pages, |
bbec2e15 | 7927 | READ_ONCE(memcg->swap.max) - |
d8b38438 VD |
7928 | page_counter_read(&memcg->swap)); |
7929 | return nr_swap_pages; | |
7930 | } | |
7931 | ||
9202d527 | 7932 | bool mem_cgroup_swap_full(struct folio *folio) |
5ccc5aba VD |
7933 | { |
7934 | struct mem_cgroup *memcg; | |
7935 | ||
9202d527 | 7936 | VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); |
5ccc5aba VD |
7937 | |
7938 | if (vm_swap_full()) | |
7939 | return true; | |
b25806dc | 7940 | if (do_memsw_account()) |
5ccc5aba VD |
7941 | return false; |
7942 | ||
9202d527 | 7943 | memcg = folio_memcg(folio); |
5ccc5aba VD |
7944 | if (!memcg) |
7945 | return false; | |
7946 | ||
7848ed62 | 7947 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) { |
4b82ab4f JK |
7948 | unsigned long usage = page_counter_read(&memcg->swap); |
7949 | ||
7950 | if (usage * 2 >= READ_ONCE(memcg->swap.high) || | |
7951 | usage * 2 >= READ_ONCE(memcg->swap.max)) | |
5ccc5aba | 7952 | return true; |
4b82ab4f | 7953 | } |
5ccc5aba VD |
7954 | |
7955 | return false; | |
7956 | } | |
7957 | ||
eccb52e7 | 7958 | static int __init setup_swap_account(char *s) |
21afa38e | 7959 | { |
b25806dc JW |
7960 | pr_warn_once("The swapaccount= commandline option is deprecated. " |
7961 | "Please report your usecase to linux-mm@kvack.org if you " | |
7962 | "depend on this functionality.\n"); | |
21afa38e JW |
7963 | return 1; |
7964 | } | |
eccb52e7 | 7965 | __setup("swapaccount=", setup_swap_account); |
21afa38e | 7966 | |
37e84351 VD |
7967 | static u64 swap_current_read(struct cgroup_subsys_state *css, |
7968 | struct cftype *cft) | |
7969 | { | |
7970 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
7971 | ||
7972 | return (u64)page_counter_read(&memcg->swap) * PAGE_SIZE; | |
7973 | } | |
7974 | ||
e0e0b412 LD |
7975 | static u64 swap_peak_read(struct cgroup_subsys_state *css, |
7976 | struct cftype *cft) | |
7977 | { | |
7978 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
7979 | ||
7980 | return (u64)memcg->swap.watermark * PAGE_SIZE; | |
7981 | } | |
7982 | ||
4b82ab4f JK |
7983 | static int swap_high_show(struct seq_file *m, void *v) |
7984 | { | |
7985 | return seq_puts_memcg_tunable(m, | |
7986 | READ_ONCE(mem_cgroup_from_seq(m)->swap.high)); | |
7987 | } | |
7988 | ||
7989 | static ssize_t swap_high_write(struct kernfs_open_file *of, | |
7990 | char *buf, size_t nbytes, loff_t off) | |
7991 | { | |
7992 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
7993 | unsigned long high; | |
7994 | int err; | |
7995 | ||
7996 | buf = strstrip(buf); | |
7997 | err = page_counter_memparse(buf, "max", &high); | |
7998 | if (err) | |
7999 | return err; | |
8000 | ||
8001 | page_counter_set_high(&memcg->swap, high); | |
8002 | ||
8003 | return nbytes; | |
8004 | } | |
8005 | ||
37e84351 VD |
8006 | static int swap_max_show(struct seq_file *m, void *v) |
8007 | { | |
677dc973 CD |
8008 | return seq_puts_memcg_tunable(m, |
8009 | READ_ONCE(mem_cgroup_from_seq(m)->swap.max)); | |
37e84351 VD |
8010 | } |
8011 | ||
8012 | static ssize_t swap_max_write(struct kernfs_open_file *of, | |
8013 | char *buf, size_t nbytes, loff_t off) | |
8014 | { | |
8015 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
8016 | unsigned long max; | |
8017 | int err; | |
8018 | ||
8019 | buf = strstrip(buf); | |
8020 | err = page_counter_memparse(buf, "max", &max); | |
8021 | if (err) | |
8022 | return err; | |
8023 | ||
be09102b | 8024 | xchg(&memcg->swap.max, max); |
37e84351 VD |
8025 | |
8026 | return nbytes; | |
8027 | } | |
8028 | ||
f3a53a3a TH |
8029 | static int swap_events_show(struct seq_file *m, void *v) |
8030 | { | |
aa9694bb | 8031 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
f3a53a3a | 8032 | |
4b82ab4f JK |
8033 | seq_printf(m, "high %lu\n", |
8034 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_HIGH])); | |
f3a53a3a TH |
8035 | seq_printf(m, "max %lu\n", |
8036 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_MAX])); | |
8037 | seq_printf(m, "fail %lu\n", | |
8038 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_FAIL])); | |
8039 | ||
8040 | return 0; | |
8041 | } | |
8042 | ||
37e84351 VD |
8043 | static struct cftype swap_files[] = { |
8044 | { | |
8045 | .name = "swap.current", | |
8046 | .flags = CFTYPE_NOT_ON_ROOT, | |
8047 | .read_u64 = swap_current_read, | |
8048 | }, | |
4b82ab4f JK |
8049 | { |
8050 | .name = "swap.high", | |
8051 | .flags = CFTYPE_NOT_ON_ROOT, | |
8052 | .seq_show = swap_high_show, | |
8053 | .write = swap_high_write, | |
8054 | }, | |
37e84351 VD |
8055 | { |
8056 | .name = "swap.max", | |
8057 | .flags = CFTYPE_NOT_ON_ROOT, | |
8058 | .seq_show = swap_max_show, | |
8059 | .write = swap_max_write, | |
8060 | }, | |
e0e0b412 LD |
8061 | { |
8062 | .name = "swap.peak", | |
8063 | .flags = CFTYPE_NOT_ON_ROOT, | |
8064 | .read_u64 = swap_peak_read, | |
8065 | }, | |
f3a53a3a TH |
8066 | { |
8067 | .name = "swap.events", | |
8068 | .flags = CFTYPE_NOT_ON_ROOT, | |
8069 | .file_offset = offsetof(struct mem_cgroup, swap_events_file), | |
8070 | .seq_show = swap_events_show, | |
8071 | }, | |
37e84351 VD |
8072 | { } /* terminate */ |
8073 | }; | |
8074 | ||
eccb52e7 | 8075 | static struct cftype memsw_files[] = { |
21afa38e JW |
8076 | { |
8077 | .name = "memsw.usage_in_bytes", | |
8078 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
8079 | .read_u64 = mem_cgroup_read_u64, | |
8080 | }, | |
8081 | { | |
8082 | .name = "memsw.max_usage_in_bytes", | |
8083 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
8084 | .write = mem_cgroup_reset, | |
8085 | .read_u64 = mem_cgroup_read_u64, | |
8086 | }, | |
8087 | { | |
8088 | .name = "memsw.limit_in_bytes", | |
8089 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
8090 | .write = mem_cgroup_write, | |
8091 | .read_u64 = mem_cgroup_read_u64, | |
8092 | }, | |
8093 | { | |
8094 | .name = "memsw.failcnt", | |
8095 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
8096 | .write = mem_cgroup_reset, | |
8097 | .read_u64 = mem_cgroup_read_u64, | |
8098 | }, | |
8099 | { }, /* terminate */ | |
8100 | }; | |
8101 | ||
f4840ccf JW |
8102 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
8103 | /** | |
8104 | * obj_cgroup_may_zswap - check if this cgroup can zswap | |
8105 | * @objcg: the object cgroup | |
8106 | * | |
8107 | * Check if the hierarchical zswap limit has been reached. | |
8108 | * | |
8109 | * This doesn't check for specific headroom, and it is not atomic | |
8110 | * either. But with zswap, the size of the allocation is only known | |
be16dd76 | 8111 | * once compression has occurred, and this optimistic pre-check avoids |
f4840ccf JW |
8112 | * spending cycles on compression when there is already no room left |
8113 | * or zswap is disabled altogether somewhere in the hierarchy. | |
8114 | */ | |
8115 | bool obj_cgroup_may_zswap(struct obj_cgroup *objcg) | |
8116 | { | |
8117 | struct mem_cgroup *memcg, *original_memcg; | |
8118 | bool ret = true; | |
8119 | ||
8120 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
8121 | return true; | |
8122 | ||
8123 | original_memcg = get_mem_cgroup_from_objcg(objcg); | |
7848ed62 | 8124 | for (memcg = original_memcg; !mem_cgroup_is_root(memcg); |
f4840ccf JW |
8125 | memcg = parent_mem_cgroup(memcg)) { |
8126 | unsigned long max = READ_ONCE(memcg->zswap_max); | |
8127 | unsigned long pages; | |
8128 | ||
8129 | if (max == PAGE_COUNTER_MAX) | |
8130 | continue; | |
8131 | if (max == 0) { | |
8132 | ret = false; | |
8133 | break; | |
8134 | } | |
8135 | ||
7d7ef0a4 YA |
8136 | /* |
8137 | * mem_cgroup_flush_stats() ignores small changes. Use | |
8138 | * do_flush_stats() directly to get accurate stats for charging. | |
8139 | */ | |
8140 | do_flush_stats(memcg); | |
f4840ccf JW |
8141 | pages = memcg_page_state(memcg, MEMCG_ZSWAP_B) / PAGE_SIZE; |
8142 | if (pages < max) | |
8143 | continue; | |
8144 | ret = false; | |
8145 | break; | |
8146 | } | |
8147 | mem_cgroup_put(original_memcg); | |
8148 | return ret; | |
8149 | } | |
8150 | ||
8151 | /** | |
8152 | * obj_cgroup_charge_zswap - charge compression backend memory | |
8153 | * @objcg: the object cgroup | |
8154 | * @size: size of compressed object | |
8155 | * | |
3a1060c2 | 8156 | * This forces the charge after obj_cgroup_may_zswap() allowed |
f4840ccf JW |
8157 | * compression and storage in zwap for this cgroup to go ahead. |
8158 | */ | |
8159 | void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size) | |
8160 | { | |
8161 | struct mem_cgroup *memcg; | |
8162 | ||
8163 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
8164 | return; | |
8165 | ||
8166 | VM_WARN_ON_ONCE(!(current->flags & PF_MEMALLOC)); | |
8167 | ||
8168 | /* PF_MEMALLOC context, charging must succeed */ | |
8169 | if (obj_cgroup_charge(objcg, GFP_KERNEL, size)) | |
8170 | VM_WARN_ON_ONCE(1); | |
8171 | ||
8172 | rcu_read_lock(); | |
8173 | memcg = obj_cgroup_memcg(objcg); | |
8174 | mod_memcg_state(memcg, MEMCG_ZSWAP_B, size); | |
8175 | mod_memcg_state(memcg, MEMCG_ZSWAPPED, 1); | |
8176 | rcu_read_unlock(); | |
8177 | } | |
8178 | ||
8179 | /** | |
8180 | * obj_cgroup_uncharge_zswap - uncharge compression backend memory | |
8181 | * @objcg: the object cgroup | |
8182 | * @size: size of compressed object | |
8183 | * | |
8184 | * Uncharges zswap memory on page in. | |
8185 | */ | |
8186 | void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size) | |
8187 | { | |
8188 | struct mem_cgroup *memcg; | |
8189 | ||
8190 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
8191 | return; | |
8192 | ||
8193 | obj_cgroup_uncharge(objcg, size); | |
8194 | ||
8195 | rcu_read_lock(); | |
8196 | memcg = obj_cgroup_memcg(objcg); | |
8197 | mod_memcg_state(memcg, MEMCG_ZSWAP_B, -size); | |
8198 | mod_memcg_state(memcg, MEMCG_ZSWAPPED, -1); | |
8199 | rcu_read_unlock(); | |
8200 | } | |
8201 | ||
501a06fe NP |
8202 | bool mem_cgroup_zswap_writeback_enabled(struct mem_cgroup *memcg) |
8203 | { | |
8204 | /* if zswap is disabled, do not block pages going to the swapping device */ | |
8205 | return !is_zswap_enabled() || !memcg || READ_ONCE(memcg->zswap_writeback); | |
8206 | } | |
8207 | ||
f4840ccf JW |
8208 | static u64 zswap_current_read(struct cgroup_subsys_state *css, |
8209 | struct cftype *cft) | |
8210 | { | |
7d7ef0a4 YA |
8211 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
8212 | ||
8213 | mem_cgroup_flush_stats(memcg); | |
8214 | return memcg_page_state(memcg, MEMCG_ZSWAP_B); | |
f4840ccf JW |
8215 | } |
8216 | ||
8217 | static int zswap_max_show(struct seq_file *m, void *v) | |
8218 | { | |
8219 | return seq_puts_memcg_tunable(m, | |
8220 | READ_ONCE(mem_cgroup_from_seq(m)->zswap_max)); | |
8221 | } | |
8222 | ||
8223 | static ssize_t zswap_max_write(struct kernfs_open_file *of, | |
8224 | char *buf, size_t nbytes, loff_t off) | |
8225 | { | |
8226 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
8227 | unsigned long max; | |
8228 | int err; | |
8229 | ||
8230 | buf = strstrip(buf); | |
8231 | err = page_counter_memparse(buf, "max", &max); | |
8232 | if (err) | |
8233 | return err; | |
8234 | ||
8235 | xchg(&memcg->zswap_max, max); | |
8236 | ||
8237 | return nbytes; | |
8238 | } | |
8239 | ||
501a06fe NP |
8240 | static int zswap_writeback_show(struct seq_file *m, void *v) |
8241 | { | |
8242 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); | |
8243 | ||
8244 | seq_printf(m, "%d\n", READ_ONCE(memcg->zswap_writeback)); | |
8245 | return 0; | |
8246 | } | |
8247 | ||
8248 | static ssize_t zswap_writeback_write(struct kernfs_open_file *of, | |
8249 | char *buf, size_t nbytes, loff_t off) | |
8250 | { | |
8251 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
8252 | int zswap_writeback; | |
8253 | ssize_t parse_ret = kstrtoint(strstrip(buf), 0, &zswap_writeback); | |
8254 | ||
8255 | if (parse_ret) | |
8256 | return parse_ret; | |
8257 | ||
8258 | if (zswap_writeback != 0 && zswap_writeback != 1) | |
8259 | return -EINVAL; | |
8260 | ||
8261 | WRITE_ONCE(memcg->zswap_writeback, zswap_writeback); | |
8262 | return nbytes; | |
8263 | } | |
8264 | ||
f4840ccf JW |
8265 | static struct cftype zswap_files[] = { |
8266 | { | |
8267 | .name = "zswap.current", | |
8268 | .flags = CFTYPE_NOT_ON_ROOT, | |
8269 | .read_u64 = zswap_current_read, | |
8270 | }, | |
8271 | { | |
8272 | .name = "zswap.max", | |
8273 | .flags = CFTYPE_NOT_ON_ROOT, | |
8274 | .seq_show = zswap_max_show, | |
8275 | .write = zswap_max_write, | |
8276 | }, | |
501a06fe NP |
8277 | { |
8278 | .name = "zswap.writeback", | |
8279 | .seq_show = zswap_writeback_show, | |
8280 | .write = zswap_writeback_write, | |
8281 | }, | |
f4840ccf JW |
8282 | { } /* terminate */ |
8283 | }; | |
8284 | #endif /* CONFIG_MEMCG_KMEM && CONFIG_ZSWAP */ | |
8285 | ||
21afa38e JW |
8286 | static int __init mem_cgroup_swap_init(void) |
8287 | { | |
2d1c4980 | 8288 | if (mem_cgroup_disabled()) |
eccb52e7 JW |
8289 | return 0; |
8290 | ||
8291 | WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, swap_files)); | |
8292 | WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, memsw_files)); | |
f4840ccf JW |
8293 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
8294 | WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, zswap_files)); | |
8295 | #endif | |
21afa38e JW |
8296 | return 0; |
8297 | } | |
b25806dc | 8298 | subsys_initcall(mem_cgroup_swap_init); |
21afa38e | 8299 | |
e55b9f96 | 8300 | #endif /* CONFIG_SWAP */ |