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> |
08e552c6 | 67 | #include "internal.h" |
d1a4c0b3 | 68 | #include <net/sock.h> |
4bd2c1ee | 69 | #include <net/ip.h> |
f35c3a8e | 70 | #include "slab.h" |
014bb1de | 71 | #include "swap.h" |
8cdea7c0 | 72 | |
7c0f6ba6 | 73 | #include <linux/uaccess.h> |
8697d331 | 74 | |
cc8e970c KM |
75 | #include <trace/events/vmscan.h> |
76 | ||
073219e9 TH |
77 | struct cgroup_subsys memory_cgrp_subsys __read_mostly; |
78 | EXPORT_SYMBOL(memory_cgrp_subsys); | |
68ae564b | 79 | |
7d828602 JW |
80 | struct mem_cgroup *root_mem_cgroup __read_mostly; |
81 | ||
37d5985c RG |
82 | /* Active memory cgroup to use from an interrupt context */ |
83 | DEFINE_PER_CPU(struct mem_cgroup *, int_active_memcg); | |
c74d40e8 | 84 | EXPORT_PER_CPU_SYMBOL_GPL(int_active_memcg); |
37d5985c | 85 | |
f7e1cb6e | 86 | /* Socket memory accounting disabled? */ |
0f0cace3 | 87 | static bool cgroup_memory_nosocket __ro_after_init; |
f7e1cb6e | 88 | |
04823c83 | 89 | /* Kernel memory accounting disabled? */ |
17c17367 | 90 | static bool cgroup_memory_nokmem __ro_after_init; |
04823c83 | 91 | |
b6c1a8af YS |
92 | /* BPF memory accounting disabled? */ |
93 | static bool cgroup_memory_nobpf __ro_after_init; | |
94 | ||
97b27821 TH |
95 | #ifdef CONFIG_CGROUP_WRITEBACK |
96 | static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq); | |
97 | #endif | |
98 | ||
7941d214 JW |
99 | /* Whether legacy memory+swap accounting is active */ |
100 | static bool do_memsw_account(void) | |
101 | { | |
b25806dc | 102 | return !cgroup_subsys_on_dfl(memory_cgrp_subsys); |
7941d214 JW |
103 | } |
104 | ||
a0db00fc KS |
105 | #define THRESHOLDS_EVENTS_TARGET 128 |
106 | #define SOFTLIMIT_EVENTS_TARGET 1024 | |
e9f8974f | 107 | |
bb4cc1a8 AM |
108 | /* |
109 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
110 | * their hierarchy representation | |
111 | */ | |
112 | ||
ef8f2327 | 113 | struct mem_cgroup_tree_per_node { |
bb4cc1a8 | 114 | struct rb_root rb_root; |
fa90b2fd | 115 | struct rb_node *rb_rightmost; |
bb4cc1a8 AM |
116 | spinlock_t lock; |
117 | }; | |
118 | ||
bb4cc1a8 AM |
119 | struct mem_cgroup_tree { |
120 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
121 | }; | |
122 | ||
123 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
124 | ||
9490ff27 KH |
125 | /* for OOM */ |
126 | struct mem_cgroup_eventfd_list { | |
127 | struct list_head list; | |
128 | struct eventfd_ctx *eventfd; | |
129 | }; | |
2e72b634 | 130 | |
79bd9814 TH |
131 | /* |
132 | * cgroup_event represents events which userspace want to receive. | |
133 | */ | |
3bc942f3 | 134 | struct mem_cgroup_event { |
79bd9814 | 135 | /* |
59b6f873 | 136 | * memcg which the event belongs to. |
79bd9814 | 137 | */ |
59b6f873 | 138 | struct mem_cgroup *memcg; |
79bd9814 TH |
139 | /* |
140 | * eventfd to signal userspace about the event. | |
141 | */ | |
142 | struct eventfd_ctx *eventfd; | |
143 | /* | |
144 | * Each of these stored in a list by the cgroup. | |
145 | */ | |
146 | struct list_head list; | |
fba94807 TH |
147 | /* |
148 | * register_event() callback will be used to add new userspace | |
149 | * waiter for changes related to this event. Use eventfd_signal() | |
150 | * on eventfd to send notification to userspace. | |
151 | */ | |
59b6f873 | 152 | int (*register_event)(struct mem_cgroup *memcg, |
347c4a87 | 153 | struct eventfd_ctx *eventfd, const char *args); |
fba94807 TH |
154 | /* |
155 | * unregister_event() callback will be called when userspace closes | |
156 | * the eventfd or on cgroup removing. This callback must be set, | |
157 | * if you want provide notification functionality. | |
158 | */ | |
59b6f873 | 159 | void (*unregister_event)(struct mem_cgroup *memcg, |
fba94807 | 160 | struct eventfd_ctx *eventfd); |
79bd9814 TH |
161 | /* |
162 | * All fields below needed to unregister event when | |
163 | * userspace closes eventfd. | |
164 | */ | |
165 | poll_table pt; | |
166 | wait_queue_head_t *wqh; | |
ac6424b9 | 167 | wait_queue_entry_t wait; |
79bd9814 TH |
168 | struct work_struct remove; |
169 | }; | |
170 | ||
c0ff4b85 R |
171 | static void mem_cgroup_threshold(struct mem_cgroup *memcg); |
172 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); | |
2e72b634 | 173 | |
7dc74be0 DN |
174 | /* Stuffs for move charges at task migration. */ |
175 | /* | |
1dfab5ab | 176 | * Types of charges to be moved. |
7dc74be0 | 177 | */ |
1dfab5ab JW |
178 | #define MOVE_ANON 0x1U |
179 | #define MOVE_FILE 0x2U | |
180 | #define MOVE_MASK (MOVE_ANON | MOVE_FILE) | |
7dc74be0 | 181 | |
4ffef5fe DN |
182 | /* "mc" and its members are protected by cgroup_mutex */ |
183 | static struct move_charge_struct { | |
b1dd693e | 184 | spinlock_t lock; /* for from, to */ |
264a0ae1 | 185 | struct mm_struct *mm; |
4ffef5fe DN |
186 | struct mem_cgroup *from; |
187 | struct mem_cgroup *to; | |
1dfab5ab | 188 | unsigned long flags; |
4ffef5fe | 189 | unsigned long precharge; |
854ffa8d | 190 | unsigned long moved_charge; |
483c30b5 | 191 | unsigned long moved_swap; |
8033b97c DN |
192 | struct task_struct *moving_task; /* a task moving charges */ |
193 | wait_queue_head_t waitq; /* a waitq for other context */ | |
194 | } mc = { | |
2bd9bb20 | 195 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
196 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
197 | }; | |
4ffef5fe | 198 | |
4e416953 | 199 | /* |
f4d005af | 200 | * Maximum loops in mem_cgroup_soft_reclaim(), used for soft |
4e416953 BS |
201 | * limit reclaim to prevent infinite loops, if they ever occur. |
202 | */ | |
a0db00fc | 203 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS 100 |
bb4cc1a8 | 204 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS 2 |
4e416953 | 205 | |
8c7c6e34 | 206 | /* for encoding cft->private value on file */ |
86ae53e1 GC |
207 | enum res_type { |
208 | _MEM, | |
209 | _MEMSWAP, | |
510fc4e1 | 210 | _KMEM, |
d55f90bf | 211 | _TCP, |
86ae53e1 GC |
212 | }; |
213 | ||
a0db00fc KS |
214 | #define MEMFILE_PRIVATE(x, val) ((x) << 16 | (val)) |
215 | #define MEMFILE_TYPE(val) ((val) >> 16 & 0xffff) | |
8c7c6e34 KH |
216 | #define MEMFILE_ATTR(val) ((val) & 0xffff) |
217 | ||
b05706f1 KT |
218 | /* |
219 | * Iteration constructs for visiting all cgroups (under a tree). If | |
220 | * loops are exited prematurely (break), mem_cgroup_iter_break() must | |
221 | * be used for reference counting. | |
222 | */ | |
223 | #define for_each_mem_cgroup_tree(iter, root) \ | |
224 | for (iter = mem_cgroup_iter(root, NULL, NULL); \ | |
225 | iter != NULL; \ | |
226 | iter = mem_cgroup_iter(root, iter, NULL)) | |
227 | ||
228 | #define for_each_mem_cgroup(iter) \ | |
229 | for (iter = mem_cgroup_iter(NULL, NULL, NULL); \ | |
230 | iter != NULL; \ | |
231 | iter = mem_cgroup_iter(NULL, iter, NULL)) | |
232 | ||
a4ebf1b6 | 233 | static inline bool task_is_dying(void) |
7775face TH |
234 | { |
235 | return tsk_is_oom_victim(current) || fatal_signal_pending(current) || | |
236 | (current->flags & PF_EXITING); | |
237 | } | |
238 | ||
70ddf637 AV |
239 | /* Some nice accessors for the vmpressure. */ |
240 | struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg) | |
241 | { | |
242 | if (!memcg) | |
243 | memcg = root_mem_cgroup; | |
244 | return &memcg->vmpressure; | |
245 | } | |
246 | ||
9647875b | 247 | struct mem_cgroup *vmpressure_to_memcg(struct vmpressure *vmpr) |
70ddf637 | 248 | { |
9647875b | 249 | return container_of(vmpr, struct mem_cgroup, vmpressure); |
70ddf637 AV |
250 | } |
251 | ||
1aacbd35 RG |
252 | #define CURRENT_OBJCG_UPDATE_BIT 0 |
253 | #define CURRENT_OBJCG_UPDATE_FLAG (1UL << CURRENT_OBJCG_UPDATE_BIT) | |
254 | ||
84c07d11 | 255 | #ifdef CONFIG_MEMCG_KMEM |
0764db9b | 256 | static DEFINE_SPINLOCK(objcg_lock); |
bf4f0599 | 257 | |
4d5c8aed RG |
258 | bool mem_cgroup_kmem_disabled(void) |
259 | { | |
260 | return cgroup_memory_nokmem; | |
261 | } | |
262 | ||
f1286fae MS |
263 | static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, |
264 | unsigned int nr_pages); | |
c1a660de | 265 | |
bf4f0599 RG |
266 | static void obj_cgroup_release(struct percpu_ref *ref) |
267 | { | |
268 | struct obj_cgroup *objcg = container_of(ref, struct obj_cgroup, refcnt); | |
bf4f0599 RG |
269 | unsigned int nr_bytes; |
270 | unsigned int nr_pages; | |
271 | unsigned long flags; | |
272 | ||
273 | /* | |
274 | * At this point all allocated objects are freed, and | |
275 | * objcg->nr_charged_bytes can't have an arbitrary byte value. | |
276 | * However, it can be PAGE_SIZE or (x * PAGE_SIZE). | |
277 | * | |
278 | * The following sequence can lead to it: | |
279 | * 1) CPU0: objcg == stock->cached_objcg | |
280 | * 2) CPU1: we do a small allocation (e.g. 92 bytes), | |
281 | * PAGE_SIZE bytes are charged | |
282 | * 3) CPU1: a process from another memcg is allocating something, | |
283 | * the stock if flushed, | |
284 | * objcg->nr_charged_bytes = PAGE_SIZE - 92 | |
285 | * 5) CPU0: we do release this object, | |
286 | * 92 bytes are added to stock->nr_bytes | |
287 | * 6) CPU0: stock is flushed, | |
288 | * 92 bytes are added to objcg->nr_charged_bytes | |
289 | * | |
290 | * In the result, nr_charged_bytes == PAGE_SIZE. | |
291 | * This page will be uncharged in obj_cgroup_release(). | |
292 | */ | |
293 | nr_bytes = atomic_read(&objcg->nr_charged_bytes); | |
294 | WARN_ON_ONCE(nr_bytes & (PAGE_SIZE - 1)); | |
295 | nr_pages = nr_bytes >> PAGE_SHIFT; | |
296 | ||
bf4f0599 | 297 | if (nr_pages) |
f1286fae | 298 | obj_cgroup_uncharge_pages(objcg, nr_pages); |
271dd6b1 | 299 | |
0764db9b | 300 | spin_lock_irqsave(&objcg_lock, flags); |
bf4f0599 | 301 | list_del(&objcg->list); |
0764db9b | 302 | spin_unlock_irqrestore(&objcg_lock, flags); |
bf4f0599 RG |
303 | |
304 | percpu_ref_exit(ref); | |
305 | kfree_rcu(objcg, rcu); | |
306 | } | |
307 | ||
308 | static struct obj_cgroup *obj_cgroup_alloc(void) | |
309 | { | |
310 | struct obj_cgroup *objcg; | |
311 | int ret; | |
312 | ||
313 | objcg = kzalloc(sizeof(struct obj_cgroup), GFP_KERNEL); | |
314 | if (!objcg) | |
315 | return NULL; | |
316 | ||
317 | ret = percpu_ref_init(&objcg->refcnt, obj_cgroup_release, 0, | |
318 | GFP_KERNEL); | |
319 | if (ret) { | |
320 | kfree(objcg); | |
321 | return NULL; | |
322 | } | |
323 | INIT_LIST_HEAD(&objcg->list); | |
324 | return objcg; | |
325 | } | |
326 | ||
327 | static void memcg_reparent_objcgs(struct mem_cgroup *memcg, | |
328 | struct mem_cgroup *parent) | |
329 | { | |
330 | struct obj_cgroup *objcg, *iter; | |
331 | ||
332 | objcg = rcu_replace_pointer(memcg->objcg, NULL, true); | |
333 | ||
0764db9b | 334 | spin_lock_irq(&objcg_lock); |
bf4f0599 | 335 | |
9838354e MS |
336 | /* 1) Ready to reparent active objcg. */ |
337 | list_add(&objcg->list, &memcg->objcg_list); | |
338 | /* 2) Reparent active objcg and already reparented objcgs to parent. */ | |
339 | list_for_each_entry(iter, &memcg->objcg_list, list) | |
340 | WRITE_ONCE(iter->memcg, parent); | |
341 | /* 3) Move already reparented objcgs to the parent's list */ | |
bf4f0599 RG |
342 | list_splice(&memcg->objcg_list, &parent->objcg_list); |
343 | ||
0764db9b | 344 | spin_unlock_irq(&objcg_lock); |
bf4f0599 RG |
345 | |
346 | percpu_ref_kill(&objcg->refcnt); | |
347 | } | |
348 | ||
d7f25f8a GC |
349 | /* |
350 | * A lot of the calls to the cache allocation functions are expected to be | |
272911a4 | 351 | * inlined by the compiler. Since the calls to memcg_slab_pre_alloc_hook() are |
d7f25f8a GC |
352 | * conditional to this static branch, we'll have to allow modules that does |
353 | * kmem_cache_alloc and the such to see this symbol as well | |
354 | */ | |
f7a449f7 RG |
355 | DEFINE_STATIC_KEY_FALSE(memcg_kmem_online_key); |
356 | EXPORT_SYMBOL(memcg_kmem_online_key); | |
b6c1a8af YS |
357 | |
358 | DEFINE_STATIC_KEY_FALSE(memcg_bpf_enabled_key); | |
359 | EXPORT_SYMBOL(memcg_bpf_enabled_key); | |
0a432dcb | 360 | #endif |
17cc4dfe | 361 | |
ad7fa852 | 362 | /** |
75376c6f MWO |
363 | * mem_cgroup_css_from_folio - css of the memcg associated with a folio |
364 | * @folio: folio of interest | |
ad7fa852 TH |
365 | * |
366 | * If memcg is bound to the default hierarchy, css of the memcg associated | |
75376c6f | 367 | * with @folio is returned. The returned css remains associated with @folio |
ad7fa852 TH |
368 | * until it is released. |
369 | * | |
370 | * If memcg is bound to a traditional hierarchy, the css of root_mem_cgroup | |
371 | * is returned. | |
ad7fa852 | 372 | */ |
75376c6f | 373 | struct cgroup_subsys_state *mem_cgroup_css_from_folio(struct folio *folio) |
ad7fa852 | 374 | { |
75376c6f | 375 | struct mem_cgroup *memcg = folio_memcg(folio); |
ad7fa852 | 376 | |
9e10a130 | 377 | if (!memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
ad7fa852 TH |
378 | memcg = root_mem_cgroup; |
379 | ||
ad7fa852 TH |
380 | return &memcg->css; |
381 | } | |
382 | ||
2fc04524 VD |
383 | /** |
384 | * page_cgroup_ino - return inode number of the memcg a page is charged to | |
385 | * @page: the page | |
386 | * | |
387 | * Look up the closest online ancestor of the memory cgroup @page is charged to | |
388 | * and return its inode number or 0 if @page is not charged to any cgroup. It | |
389 | * is safe to call this function without holding a reference to @page. | |
390 | * | |
391 | * Note, this function is inherently racy, because there is nothing to prevent | |
392 | * the cgroup inode from getting torn down and potentially reallocated a moment | |
393 | * after page_cgroup_ino() returns, so it only should be used by callers that | |
394 | * do not care (such as procfs interfaces). | |
395 | */ | |
396 | ino_t page_cgroup_ino(struct page *page) | |
397 | { | |
398 | struct mem_cgroup *memcg; | |
399 | unsigned long ino = 0; | |
400 | ||
401 | rcu_read_lock(); | |
ec342603 YA |
402 | /* page_folio() is racy here, but the entire function is racy anyway */ |
403 | memcg = folio_memcg_check(page_folio(page)); | |
286e04b8 | 404 | |
2fc04524 VD |
405 | while (memcg && !(memcg->css.flags & CSS_ONLINE)) |
406 | memcg = parent_mem_cgroup(memcg); | |
407 | if (memcg) | |
408 | ino = cgroup_ino(memcg->css.cgroup); | |
409 | rcu_read_unlock(); | |
410 | return ino; | |
411 | } | |
412 | ||
ef8f2327 MG |
413 | static void __mem_cgroup_insert_exceeded(struct mem_cgroup_per_node *mz, |
414 | struct mem_cgroup_tree_per_node *mctz, | |
3e32cb2e | 415 | unsigned long new_usage_in_excess) |
bb4cc1a8 AM |
416 | { |
417 | struct rb_node **p = &mctz->rb_root.rb_node; | |
418 | struct rb_node *parent = NULL; | |
ef8f2327 | 419 | struct mem_cgroup_per_node *mz_node; |
fa90b2fd | 420 | bool rightmost = true; |
bb4cc1a8 AM |
421 | |
422 | if (mz->on_tree) | |
423 | return; | |
424 | ||
425 | mz->usage_in_excess = new_usage_in_excess; | |
426 | if (!mz->usage_in_excess) | |
427 | return; | |
428 | while (*p) { | |
429 | parent = *p; | |
ef8f2327 | 430 | mz_node = rb_entry(parent, struct mem_cgroup_per_node, |
bb4cc1a8 | 431 | tree_node); |
fa90b2fd | 432 | if (mz->usage_in_excess < mz_node->usage_in_excess) { |
bb4cc1a8 | 433 | p = &(*p)->rb_left; |
fa90b2fd | 434 | rightmost = false; |
378876b0 | 435 | } else { |
bb4cc1a8 | 436 | p = &(*p)->rb_right; |
378876b0 | 437 | } |
bb4cc1a8 | 438 | } |
fa90b2fd DB |
439 | |
440 | if (rightmost) | |
441 | mctz->rb_rightmost = &mz->tree_node; | |
442 | ||
bb4cc1a8 AM |
443 | rb_link_node(&mz->tree_node, parent, p); |
444 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
445 | mz->on_tree = true; | |
446 | } | |
447 | ||
ef8f2327 MG |
448 | static void __mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz, |
449 | struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 AM |
450 | { |
451 | if (!mz->on_tree) | |
452 | return; | |
fa90b2fd DB |
453 | |
454 | if (&mz->tree_node == mctz->rb_rightmost) | |
455 | mctz->rb_rightmost = rb_prev(&mz->tree_node); | |
456 | ||
bb4cc1a8 AM |
457 | rb_erase(&mz->tree_node, &mctz->rb_root); |
458 | mz->on_tree = false; | |
459 | } | |
460 | ||
ef8f2327 MG |
461 | static void mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz, |
462 | struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 463 | { |
0a31bc97 JW |
464 | unsigned long flags; |
465 | ||
466 | spin_lock_irqsave(&mctz->lock, flags); | |
cf2c8127 | 467 | __mem_cgroup_remove_exceeded(mz, mctz); |
0a31bc97 | 468 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
469 | } |
470 | ||
3e32cb2e JW |
471 | static unsigned long soft_limit_excess(struct mem_cgroup *memcg) |
472 | { | |
473 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
4db0c3c2 | 474 | unsigned long soft_limit = READ_ONCE(memcg->soft_limit); |
3e32cb2e JW |
475 | unsigned long excess = 0; |
476 | ||
477 | if (nr_pages > soft_limit) | |
478 | excess = nr_pages - soft_limit; | |
479 | ||
480 | return excess; | |
481 | } | |
bb4cc1a8 | 482 | |
658b69c9 | 483 | static void mem_cgroup_update_tree(struct mem_cgroup *memcg, int nid) |
bb4cc1a8 | 484 | { |
3e32cb2e | 485 | unsigned long excess; |
ef8f2327 MG |
486 | struct mem_cgroup_per_node *mz; |
487 | struct mem_cgroup_tree_per_node *mctz; | |
bb4cc1a8 | 488 | |
e4dde56c | 489 | if (lru_gen_enabled()) { |
36c7b4db | 490 | if (soft_limit_excess(memcg)) |
5c7e7a0d | 491 | lru_gen_soft_reclaim(memcg, nid); |
e4dde56c YZ |
492 | return; |
493 | } | |
494 | ||
2ab082ba | 495 | mctz = soft_limit_tree.rb_tree_per_node[nid]; |
bfc7228b LD |
496 | if (!mctz) |
497 | return; | |
bb4cc1a8 AM |
498 | /* |
499 | * Necessary to update all ancestors when hierarchy is used. | |
500 | * because their event counter is not touched. | |
501 | */ | |
502 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
658b69c9 | 503 | mz = memcg->nodeinfo[nid]; |
3e32cb2e | 504 | excess = soft_limit_excess(memcg); |
bb4cc1a8 AM |
505 | /* |
506 | * We have to update the tree if mz is on RB-tree or | |
507 | * mem is over its softlimit. | |
508 | */ | |
509 | if (excess || mz->on_tree) { | |
0a31bc97 JW |
510 | unsigned long flags; |
511 | ||
512 | spin_lock_irqsave(&mctz->lock, flags); | |
bb4cc1a8 AM |
513 | /* if on-tree, remove it */ |
514 | if (mz->on_tree) | |
cf2c8127 | 515 | __mem_cgroup_remove_exceeded(mz, mctz); |
bb4cc1a8 AM |
516 | /* |
517 | * Insert again. mz->usage_in_excess will be updated. | |
518 | * If excess is 0, no tree ops. | |
519 | */ | |
cf2c8127 | 520 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 521 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
522 | } |
523 | } | |
524 | } | |
525 | ||
526 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) | |
527 | { | |
ef8f2327 MG |
528 | struct mem_cgroup_tree_per_node *mctz; |
529 | struct mem_cgroup_per_node *mz; | |
530 | int nid; | |
bb4cc1a8 | 531 | |
e231875b | 532 | for_each_node(nid) { |
a3747b53 | 533 | mz = memcg->nodeinfo[nid]; |
2ab082ba | 534 | mctz = soft_limit_tree.rb_tree_per_node[nid]; |
bfc7228b LD |
535 | if (mctz) |
536 | mem_cgroup_remove_exceeded(mz, mctz); | |
bb4cc1a8 AM |
537 | } |
538 | } | |
539 | ||
ef8f2327 MG |
540 | static struct mem_cgroup_per_node * |
541 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 542 | { |
ef8f2327 | 543 | struct mem_cgroup_per_node *mz; |
bb4cc1a8 AM |
544 | |
545 | retry: | |
546 | mz = NULL; | |
fa90b2fd | 547 | if (!mctz->rb_rightmost) |
bb4cc1a8 AM |
548 | goto done; /* Nothing to reclaim from */ |
549 | ||
fa90b2fd DB |
550 | mz = rb_entry(mctz->rb_rightmost, |
551 | struct mem_cgroup_per_node, tree_node); | |
bb4cc1a8 AM |
552 | /* |
553 | * Remove the node now but someone else can add it back, | |
554 | * we will to add it back at the end of reclaim to its correct | |
555 | * position in the tree. | |
556 | */ | |
cf2c8127 | 557 | __mem_cgroup_remove_exceeded(mz, mctz); |
3e32cb2e | 558 | if (!soft_limit_excess(mz->memcg) || |
8965aa28 | 559 | !css_tryget(&mz->memcg->css)) |
bb4cc1a8 AM |
560 | goto retry; |
561 | done: | |
562 | return mz; | |
563 | } | |
564 | ||
ef8f2327 MG |
565 | static struct mem_cgroup_per_node * |
566 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 567 | { |
ef8f2327 | 568 | struct mem_cgroup_per_node *mz; |
bb4cc1a8 | 569 | |
0a31bc97 | 570 | spin_lock_irq(&mctz->lock); |
bb4cc1a8 | 571 | mz = __mem_cgroup_largest_soft_limit_node(mctz); |
0a31bc97 | 572 | spin_unlock_irq(&mctz->lock); |
bb4cc1a8 AM |
573 | return mz; |
574 | } | |
575 | ||
11192d9c SB |
576 | /* |
577 | * memcg and lruvec stats flushing | |
578 | * | |
579 | * Many codepaths leading to stats update or read are performance sensitive and | |
580 | * adding stats flushing in such codepaths is not desirable. So, to optimize the | |
581 | * flushing the kernel does: | |
582 | * | |
583 | * 1) Periodically and asynchronously flush the stats every 2 seconds to not let | |
584 | * rstat update tree grow unbounded. | |
585 | * | |
586 | * 2) Flush the stats synchronously on reader side only when there are more than | |
587 | * (MEMCG_CHARGE_BATCH * nr_cpus) update events. Though this optimization | |
588 | * will let stats be out of sync by atmost (MEMCG_CHARGE_BATCH * nr_cpus) but | |
589 | * only for 2 seconds due to (1). | |
590 | */ | |
591 | static void flush_memcg_stats_dwork(struct work_struct *w); | |
592 | static DECLARE_DEFERRABLE_WORK(stats_flush_dwork, flush_memcg_stats_dwork); | |
11192d9c | 593 | static DEFINE_PER_CPU(unsigned int, stats_updates); |
3cd9992b | 594 | static atomic_t stats_flush_ongoing = ATOMIC_INIT(0); |
11192d9c | 595 | static atomic_t stats_flush_threshold = ATOMIC_INIT(0); |
9b301615 SB |
596 | static u64 flush_next_time; |
597 | ||
598 | #define FLUSH_TIME (2UL*HZ) | |
11192d9c | 599 | |
be3e67b5 SAS |
600 | /* |
601 | * Accessors to ensure that preemption is disabled on PREEMPT_RT because it can | |
602 | * not rely on this as part of an acquired spinlock_t lock. These functions are | |
603 | * never used in hardirq context on PREEMPT_RT and therefore disabling preemtion | |
604 | * is sufficient. | |
605 | */ | |
606 | static void memcg_stats_lock(void) | |
607 | { | |
e575d401 TG |
608 | preempt_disable_nested(); |
609 | VM_WARN_ON_IRQS_ENABLED(); | |
be3e67b5 SAS |
610 | } |
611 | ||
612 | static void __memcg_stats_lock(void) | |
613 | { | |
e575d401 | 614 | preempt_disable_nested(); |
be3e67b5 SAS |
615 | } |
616 | ||
617 | static void memcg_stats_unlock(void) | |
618 | { | |
e575d401 | 619 | preempt_enable_nested(); |
be3e67b5 SAS |
620 | } |
621 | ||
5b3be698 | 622 | static inline void memcg_rstat_updated(struct mem_cgroup *memcg, int val) |
11192d9c | 623 | { |
5b3be698 SB |
624 | unsigned int x; |
625 | ||
f9d911ca YA |
626 | if (!val) |
627 | return; | |
628 | ||
11192d9c | 629 | cgroup_rstat_updated(memcg->css.cgroup, smp_processor_id()); |
5b3be698 SB |
630 | |
631 | x = __this_cpu_add_return(stats_updates, abs(val)); | |
632 | if (x > MEMCG_CHARGE_BATCH) { | |
873f64b7 JS |
633 | /* |
634 | * If stats_flush_threshold exceeds the threshold | |
635 | * (>num_online_cpus()), cgroup stats update will be triggered | |
636 | * in __mem_cgroup_flush_stats(). Increasing this var further | |
637 | * is redundant and simply adds overhead in atomic update. | |
638 | */ | |
639 | if (atomic_read(&stats_flush_threshold) <= num_online_cpus()) | |
640 | atomic_add(x / MEMCG_CHARGE_BATCH, &stats_flush_threshold); | |
5b3be698 SB |
641 | __this_cpu_write(stats_updates, 0); |
642 | } | |
11192d9c SB |
643 | } |
644 | ||
35822fda | 645 | static void do_flush_stats(void) |
11192d9c | 646 | { |
3cd9992b YA |
647 | /* |
648 | * We always flush the entire tree, so concurrent flushers can just | |
649 | * skip. This avoids a thundering herd problem on the rstat global lock | |
650 | * from memcg flushers (e.g. reclaim, refault, etc). | |
651 | */ | |
652 | if (atomic_read(&stats_flush_ongoing) || | |
653 | atomic_xchg(&stats_flush_ongoing, 1)) | |
11192d9c SB |
654 | return; |
655 | ||
3cd9992b | 656 | WRITE_ONCE(flush_next_time, jiffies_64 + 2*FLUSH_TIME); |
9fad9aee | 657 | |
35822fda | 658 | cgroup_rstat_flush(root_mem_cgroup->css.cgroup); |
9fad9aee | 659 | |
11192d9c | 660 | atomic_set(&stats_flush_threshold, 0); |
3cd9992b | 661 | atomic_set(&stats_flush_ongoing, 0); |
11192d9c SB |
662 | } |
663 | ||
664 | void mem_cgroup_flush_stats(void) | |
665 | { | |
35822fda YA |
666 | if (atomic_read(&stats_flush_threshold) > num_online_cpus()) |
667 | do_flush_stats(); | |
9fad9aee YA |
668 | } |
669 | ||
4009b2f1 | 670 | void mem_cgroup_flush_stats_ratelimited(void) |
9b301615 | 671 | { |
3cd9992b | 672 | if (time_after64(jiffies_64, READ_ONCE(flush_next_time))) |
4009b2f1 | 673 | mem_cgroup_flush_stats(); |
9b301615 SB |
674 | } |
675 | ||
11192d9c SB |
676 | static void flush_memcg_stats_dwork(struct work_struct *w) |
677 | { | |
9fad9aee YA |
678 | /* |
679 | * Always flush here so that flushing in latency-sensitive paths is | |
680 | * as cheap as possible. | |
681 | */ | |
35822fda | 682 | do_flush_stats(); |
9b301615 | 683 | queue_delayed_work(system_unbound_wq, &stats_flush_dwork, FLUSH_TIME); |
11192d9c SB |
684 | } |
685 | ||
d396def5 SB |
686 | /* Subset of vm_event_item to report for memcg event stats */ |
687 | static const unsigned int memcg_vm_event_stat[] = { | |
8278f1c7 SB |
688 | PGPGIN, |
689 | PGPGOUT, | |
d396def5 SB |
690 | PGSCAN_KSWAPD, |
691 | PGSCAN_DIRECT, | |
57e9cc50 | 692 | PGSCAN_KHUGEPAGED, |
d396def5 SB |
693 | PGSTEAL_KSWAPD, |
694 | PGSTEAL_DIRECT, | |
57e9cc50 | 695 | PGSTEAL_KHUGEPAGED, |
d396def5 SB |
696 | PGFAULT, |
697 | PGMAJFAULT, | |
698 | PGREFILL, | |
699 | PGACTIVATE, | |
700 | PGDEACTIVATE, | |
701 | PGLAZYFREE, | |
702 | PGLAZYFREED, | |
703 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) | |
704 | ZSWPIN, | |
705 | ZSWPOUT, | |
706 | #endif | |
707 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
708 | THP_FAULT_ALLOC, | |
709 | THP_COLLAPSE_ALLOC, | |
811244a5 XH |
710 | THP_SWPOUT, |
711 | THP_SWPOUT_FALLBACK, | |
d396def5 SB |
712 | #endif |
713 | }; | |
714 | ||
8278f1c7 SB |
715 | #define NR_MEMCG_EVENTS ARRAY_SIZE(memcg_vm_event_stat) |
716 | static int mem_cgroup_events_index[NR_VM_EVENT_ITEMS] __read_mostly; | |
717 | ||
718 | static void init_memcg_events(void) | |
719 | { | |
720 | int i; | |
721 | ||
722 | for (i = 0; i < NR_MEMCG_EVENTS; ++i) | |
723 | mem_cgroup_events_index[memcg_vm_event_stat[i]] = i + 1; | |
724 | } | |
725 | ||
726 | static inline int memcg_events_index(enum vm_event_item idx) | |
727 | { | |
728 | return mem_cgroup_events_index[idx] - 1; | |
729 | } | |
730 | ||
410f8e82 SB |
731 | struct memcg_vmstats_percpu { |
732 | /* Local (CPU and cgroup) page state & events */ | |
733 | long state[MEMCG_NR_STAT]; | |
8278f1c7 | 734 | unsigned long events[NR_MEMCG_EVENTS]; |
410f8e82 SB |
735 | |
736 | /* Delta calculation for lockless upward propagation */ | |
737 | long state_prev[MEMCG_NR_STAT]; | |
8278f1c7 | 738 | unsigned long events_prev[NR_MEMCG_EVENTS]; |
410f8e82 SB |
739 | |
740 | /* Cgroup1: threshold notifications & softlimit tree updates */ | |
741 | unsigned long nr_page_events; | |
742 | unsigned long targets[MEM_CGROUP_NTARGETS]; | |
743 | }; | |
744 | ||
745 | struct memcg_vmstats { | |
746 | /* Aggregated (CPU and subtree) page state & events */ | |
747 | long state[MEMCG_NR_STAT]; | |
8278f1c7 | 748 | unsigned long events[NR_MEMCG_EVENTS]; |
410f8e82 | 749 | |
f82e6bf9 YA |
750 | /* Non-hierarchical (CPU aggregated) page state & events */ |
751 | long state_local[MEMCG_NR_STAT]; | |
752 | unsigned long events_local[NR_MEMCG_EVENTS]; | |
753 | ||
410f8e82 SB |
754 | /* Pending child counts during tree propagation */ |
755 | long state_pending[MEMCG_NR_STAT]; | |
8278f1c7 | 756 | unsigned long events_pending[NR_MEMCG_EVENTS]; |
410f8e82 SB |
757 | }; |
758 | ||
759 | unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx) | |
760 | { | |
761 | long x = READ_ONCE(memcg->vmstats->state[idx]); | |
762 | #ifdef CONFIG_SMP | |
763 | if (x < 0) | |
764 | x = 0; | |
765 | #endif | |
766 | return x; | |
767 | } | |
768 | ||
7bd5bc3c YA |
769 | static int memcg_page_state_unit(int item); |
770 | ||
771 | /* | |
772 | * Normalize the value passed into memcg_rstat_updated() to be in pages. Round | |
773 | * up non-zero sub-page updates to 1 page as zero page updates are ignored. | |
774 | */ | |
775 | static int memcg_state_val_in_pages(int idx, int val) | |
776 | { | |
777 | int unit = memcg_page_state_unit(idx); | |
778 | ||
779 | if (!val || unit == PAGE_SIZE) | |
780 | return val; | |
781 | else | |
782 | return max(val * unit / PAGE_SIZE, 1UL); | |
783 | } | |
784 | ||
db9adbcb JW |
785 | /** |
786 | * __mod_memcg_state - update cgroup memory statistics | |
787 | * @memcg: the memory cgroup | |
788 | * @idx: the stat item - can be enum memcg_stat_item or enum node_stat_item | |
789 | * @val: delta to add to the counter, can be negative | |
790 | */ | |
791 | void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val) | |
792 | { | |
db9adbcb JW |
793 | if (mem_cgroup_disabled()) |
794 | return; | |
795 | ||
2d146aa3 | 796 | __this_cpu_add(memcg->vmstats_percpu->state[idx], val); |
7bd5bc3c | 797 | memcg_rstat_updated(memcg, memcg_state_val_in_pages(idx, val)); |
db9adbcb JW |
798 | } |
799 | ||
2d146aa3 | 800 | /* idx can be of type enum memcg_stat_item or node_stat_item. */ |
a18e6e6e JW |
801 | static unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx) |
802 | { | |
f82e6bf9 | 803 | long x = READ_ONCE(memcg->vmstats->state_local[idx]); |
a18e6e6e | 804 | |
a18e6e6e JW |
805 | #ifdef CONFIG_SMP |
806 | if (x < 0) | |
807 | x = 0; | |
808 | #endif | |
809 | return x; | |
810 | } | |
811 | ||
eedc4e5a RG |
812 | void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, |
813 | int val) | |
db9adbcb JW |
814 | { |
815 | struct mem_cgroup_per_node *pn; | |
42a30035 | 816 | struct mem_cgroup *memcg; |
db9adbcb | 817 | |
db9adbcb | 818 | pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec); |
42a30035 | 819 | memcg = pn->memcg; |
db9adbcb | 820 | |
be3e67b5 | 821 | /* |
be16dd76 | 822 | * The caller from rmap relies on disabled preemption because they never |
be3e67b5 SAS |
823 | * update their counter from in-interrupt context. For these two |
824 | * counters we check that the update is never performed from an | |
825 | * interrupt context while other caller need to have disabled interrupt. | |
826 | */ | |
827 | __memcg_stats_lock(); | |
e575d401 | 828 | if (IS_ENABLED(CONFIG_DEBUG_VM)) { |
be3e67b5 SAS |
829 | switch (idx) { |
830 | case NR_ANON_MAPPED: | |
831 | case NR_FILE_MAPPED: | |
832 | case NR_ANON_THPS: | |
833 | case NR_SHMEM_PMDMAPPED: | |
834 | case NR_FILE_PMDMAPPED: | |
835 | WARN_ON_ONCE(!in_task()); | |
836 | break; | |
837 | default: | |
e575d401 | 838 | VM_WARN_ON_IRQS_ENABLED(); |
be3e67b5 SAS |
839 | } |
840 | } | |
841 | ||
db9adbcb | 842 | /* Update memcg */ |
11192d9c | 843 | __this_cpu_add(memcg->vmstats_percpu->state[idx], val); |
db9adbcb | 844 | |
b4c46484 | 845 | /* Update lruvec */ |
7e1c0d6f | 846 | __this_cpu_add(pn->lruvec_stats_percpu->state[idx], val); |
11192d9c | 847 | |
7bd5bc3c | 848 | memcg_rstat_updated(memcg, memcg_state_val_in_pages(idx, val)); |
be3e67b5 | 849 | memcg_stats_unlock(); |
db9adbcb JW |
850 | } |
851 | ||
eedc4e5a RG |
852 | /** |
853 | * __mod_lruvec_state - update lruvec memory statistics | |
854 | * @lruvec: the lruvec | |
855 | * @idx: the stat item | |
856 | * @val: delta to add to the counter, can be negative | |
857 | * | |
858 | * The lruvec is the intersection of the NUMA node and a cgroup. This | |
859 | * function updates the all three counters that are affected by a | |
860 | * change of state at this level: per-node, per-cgroup, per-lruvec. | |
861 | */ | |
862 | void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, | |
863 | int val) | |
864 | { | |
865 | /* Update node */ | |
866 | __mod_node_page_state(lruvec_pgdat(lruvec), idx, val); | |
867 | ||
868 | /* Update memcg and lruvec */ | |
869 | if (!mem_cgroup_disabled()) | |
870 | __mod_memcg_lruvec_state(lruvec, idx, val); | |
871 | } | |
872 | ||
c47d5032 SB |
873 | void __mod_lruvec_page_state(struct page *page, enum node_stat_item idx, |
874 | int val) | |
875 | { | |
876 | struct page *head = compound_head(page); /* rmap on tail pages */ | |
b4e0b68f | 877 | struct mem_cgroup *memcg; |
c47d5032 SB |
878 | pg_data_t *pgdat = page_pgdat(page); |
879 | struct lruvec *lruvec; | |
880 | ||
b4e0b68f MS |
881 | rcu_read_lock(); |
882 | memcg = page_memcg(head); | |
c47d5032 | 883 | /* Untracked pages have no memcg, no lruvec. Update only the node */ |
d635a69d | 884 | if (!memcg) { |
b4e0b68f | 885 | rcu_read_unlock(); |
c47d5032 SB |
886 | __mod_node_page_state(pgdat, idx, val); |
887 | return; | |
888 | } | |
889 | ||
d635a69d | 890 | lruvec = mem_cgroup_lruvec(memcg, pgdat); |
c47d5032 | 891 | __mod_lruvec_state(lruvec, idx, val); |
b4e0b68f | 892 | rcu_read_unlock(); |
c47d5032 | 893 | } |
f0c0c115 | 894 | EXPORT_SYMBOL(__mod_lruvec_page_state); |
c47d5032 | 895 | |
da3ceeff | 896 | void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) |
ec9f0238 | 897 | { |
4f103c63 | 898 | pg_data_t *pgdat = page_pgdat(virt_to_page(p)); |
ec9f0238 RG |
899 | struct mem_cgroup *memcg; |
900 | struct lruvec *lruvec; | |
901 | ||
902 | rcu_read_lock(); | |
fc4db90f | 903 | memcg = mem_cgroup_from_slab_obj(p); |
ec9f0238 | 904 | |
8faeb1ff MS |
905 | /* |
906 | * Untracked pages have no memcg, no lruvec. Update only the | |
907 | * node. If we reparent the slab objects to the root memcg, | |
908 | * when we free the slab object, we need to update the per-memcg | |
909 | * vmstats to keep it correct for the root memcg. | |
910 | */ | |
911 | if (!memcg) { | |
ec9f0238 RG |
912 | __mod_node_page_state(pgdat, idx, val); |
913 | } else { | |
867e5e1d | 914 | lruvec = mem_cgroup_lruvec(memcg, pgdat); |
ec9f0238 RG |
915 | __mod_lruvec_state(lruvec, idx, val); |
916 | } | |
917 | rcu_read_unlock(); | |
918 | } | |
919 | ||
db9adbcb JW |
920 | /** |
921 | * __count_memcg_events - account VM events in a cgroup | |
922 | * @memcg: the memory cgroup | |
923 | * @idx: the event item | |
f0953a1b | 924 | * @count: the number of events that occurred |
db9adbcb JW |
925 | */ |
926 | void __count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx, | |
927 | unsigned long count) | |
928 | { | |
8278f1c7 SB |
929 | int index = memcg_events_index(idx); |
930 | ||
931 | if (mem_cgroup_disabled() || index < 0) | |
db9adbcb JW |
932 | return; |
933 | ||
be3e67b5 | 934 | memcg_stats_lock(); |
8278f1c7 | 935 | __this_cpu_add(memcg->vmstats_percpu->events[index], count); |
5b3be698 | 936 | memcg_rstat_updated(memcg, count); |
be3e67b5 | 937 | memcg_stats_unlock(); |
db9adbcb JW |
938 | } |
939 | ||
42a30035 | 940 | static unsigned long memcg_events(struct mem_cgroup *memcg, int event) |
e9f8974f | 941 | { |
8278f1c7 SB |
942 | int index = memcg_events_index(event); |
943 | ||
944 | if (index < 0) | |
945 | return 0; | |
946 | return READ_ONCE(memcg->vmstats->events[index]); | |
e9f8974f JW |
947 | } |
948 | ||
42a30035 JW |
949 | static unsigned long memcg_events_local(struct mem_cgroup *memcg, int event) |
950 | { | |
8278f1c7 SB |
951 | int index = memcg_events_index(event); |
952 | ||
953 | if (index < 0) | |
954 | return 0; | |
815744d7 | 955 | |
f82e6bf9 | 956 | return READ_ONCE(memcg->vmstats->events_local[index]); |
42a30035 JW |
957 | } |
958 | ||
c0ff4b85 | 959 | static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, |
3fba69a5 | 960 | int nr_pages) |
d52aa412 | 961 | { |
e401f176 KH |
962 | /* pagein of a big page is an event. So, ignore page size */ |
963 | if (nr_pages > 0) | |
c9019e9b | 964 | __count_memcg_events(memcg, PGPGIN, 1); |
3751d604 | 965 | else { |
c9019e9b | 966 | __count_memcg_events(memcg, PGPGOUT, 1); |
3751d604 KH |
967 | nr_pages = -nr_pages; /* for event */ |
968 | } | |
e401f176 | 969 | |
871789d4 | 970 | __this_cpu_add(memcg->vmstats_percpu->nr_page_events, nr_pages); |
6d12e2d8 KH |
971 | } |
972 | ||
f53d7ce3 JW |
973 | static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg, |
974 | enum mem_cgroup_events_target target) | |
7a159cc9 JW |
975 | { |
976 | unsigned long val, next; | |
977 | ||
871789d4 CD |
978 | val = __this_cpu_read(memcg->vmstats_percpu->nr_page_events); |
979 | next = __this_cpu_read(memcg->vmstats_percpu->targets[target]); | |
7a159cc9 | 980 | /* from time_after() in jiffies.h */ |
6a1a8b80 | 981 | if ((long)(next - val) < 0) { |
f53d7ce3 JW |
982 | switch (target) { |
983 | case MEM_CGROUP_TARGET_THRESH: | |
984 | next = val + THRESHOLDS_EVENTS_TARGET; | |
985 | break; | |
bb4cc1a8 AM |
986 | case MEM_CGROUP_TARGET_SOFTLIMIT: |
987 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
988 | break; | |
f53d7ce3 JW |
989 | default: |
990 | break; | |
991 | } | |
871789d4 | 992 | __this_cpu_write(memcg->vmstats_percpu->targets[target], next); |
f53d7ce3 | 993 | return true; |
7a159cc9 | 994 | } |
f53d7ce3 | 995 | return false; |
d2265e6f KH |
996 | } |
997 | ||
998 | /* | |
999 | * Check events in order. | |
1000 | * | |
1001 | */ | |
8e88bd2d | 1002 | static void memcg_check_events(struct mem_cgroup *memcg, int nid) |
d2265e6f | 1003 | { |
2343e88d SAS |
1004 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) |
1005 | return; | |
1006 | ||
d2265e6f | 1007 | /* threshold event is triggered in finer grain than soft limit */ |
f53d7ce3 JW |
1008 | if (unlikely(mem_cgroup_event_ratelimit(memcg, |
1009 | MEM_CGROUP_TARGET_THRESH))) { | |
bb4cc1a8 | 1010 | bool do_softlimit; |
f53d7ce3 | 1011 | |
bb4cc1a8 AM |
1012 | do_softlimit = mem_cgroup_event_ratelimit(memcg, |
1013 | MEM_CGROUP_TARGET_SOFTLIMIT); | |
c0ff4b85 | 1014 | mem_cgroup_threshold(memcg); |
bb4cc1a8 | 1015 | if (unlikely(do_softlimit)) |
8e88bd2d | 1016 | mem_cgroup_update_tree(memcg, nid); |
0a31bc97 | 1017 | } |
d2265e6f KH |
1018 | } |
1019 | ||
cf475ad2 | 1020 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 1021 | { |
31a78f23 BS |
1022 | /* |
1023 | * mm_update_next_owner() may clear mm->owner to NULL | |
1024 | * if it races with swapoff, page migration, etc. | |
1025 | * So this can be called with p == NULL. | |
1026 | */ | |
1027 | if (unlikely(!p)) | |
1028 | return NULL; | |
1029 | ||
073219e9 | 1030 | return mem_cgroup_from_css(task_css(p, memory_cgrp_id)); |
78fb7466 | 1031 | } |
33398cf2 | 1032 | EXPORT_SYMBOL(mem_cgroup_from_task); |
78fb7466 | 1033 | |
04f94e3f DS |
1034 | static __always_inline struct mem_cgroup *active_memcg(void) |
1035 | { | |
55a68c82 | 1036 | if (!in_task()) |
04f94e3f DS |
1037 | return this_cpu_read(int_active_memcg); |
1038 | else | |
1039 | return current->active_memcg; | |
1040 | } | |
1041 | ||
d46eb14b SB |
1042 | /** |
1043 | * get_mem_cgroup_from_mm: Obtain a reference on given mm_struct's memcg. | |
1044 | * @mm: mm from which memcg should be extracted. It can be NULL. | |
1045 | * | |
04f94e3f DS |
1046 | * Obtain a reference on mm->memcg and returns it if successful. If mm |
1047 | * is NULL, then the memcg is chosen as follows: | |
1048 | * 1) The active memcg, if set. | |
1049 | * 2) current->mm->memcg, if available | |
1050 | * 3) root memcg | |
1051 | * If mem_cgroup is disabled, NULL is returned. | |
d46eb14b SB |
1052 | */ |
1053 | struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm) | |
54595fe2 | 1054 | { |
d46eb14b SB |
1055 | struct mem_cgroup *memcg; |
1056 | ||
1057 | if (mem_cgroup_disabled()) | |
1058 | return NULL; | |
0b7f569e | 1059 | |
2884b6b7 MS |
1060 | /* |
1061 | * Page cache insertions can happen without an | |
1062 | * actual mm context, e.g. during disk probing | |
1063 | * on boot, loopback IO, acct() writes etc. | |
1064 | * | |
1065 | * No need to css_get on root memcg as the reference | |
1066 | * counting is disabled on the root level in the | |
1067 | * cgroup core. See CSS_NO_REF. | |
1068 | */ | |
04f94e3f DS |
1069 | if (unlikely(!mm)) { |
1070 | memcg = active_memcg(); | |
1071 | if (unlikely(memcg)) { | |
1072 | /* remote memcg must hold a ref */ | |
1073 | css_get(&memcg->css); | |
1074 | return memcg; | |
1075 | } | |
1076 | mm = current->mm; | |
1077 | if (unlikely(!mm)) | |
1078 | return root_mem_cgroup; | |
1079 | } | |
2884b6b7 | 1080 | |
54595fe2 KH |
1081 | rcu_read_lock(); |
1082 | do { | |
2884b6b7 MS |
1083 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); |
1084 | if (unlikely(!memcg)) | |
df381975 | 1085 | memcg = root_mem_cgroup; |
00d484f3 | 1086 | } while (!css_tryget(&memcg->css)); |
54595fe2 | 1087 | rcu_read_unlock(); |
c0ff4b85 | 1088 | return memcg; |
54595fe2 | 1089 | } |
d46eb14b SB |
1090 | EXPORT_SYMBOL(get_mem_cgroup_from_mm); |
1091 | ||
4b569387 NP |
1092 | /** |
1093 | * get_mem_cgroup_from_current - Obtain a reference on current task's memcg. | |
1094 | */ | |
1095 | struct mem_cgroup *get_mem_cgroup_from_current(void) | |
1096 | { | |
1097 | struct mem_cgroup *memcg; | |
1098 | ||
1099 | if (mem_cgroup_disabled()) | |
1100 | return NULL; | |
1101 | ||
1102 | again: | |
1103 | rcu_read_lock(); | |
1104 | memcg = mem_cgroup_from_task(current); | |
1105 | if (!css_tryget(&memcg->css)) { | |
1106 | rcu_read_unlock(); | |
1107 | goto again; | |
1108 | } | |
1109 | rcu_read_unlock(); | |
1110 | return memcg; | |
1111 | } | |
1112 | ||
5660048c JW |
1113 | /** |
1114 | * mem_cgroup_iter - iterate over memory cgroup hierarchy | |
1115 | * @root: hierarchy root | |
1116 | * @prev: previously returned memcg, NULL on first invocation | |
1117 | * @reclaim: cookie for shared reclaim walks, NULL for full walks | |
1118 | * | |
1119 | * Returns references to children of the hierarchy below @root, or | |
1120 | * @root itself, or %NULL after a full round-trip. | |
1121 | * | |
1122 | * Caller must pass the return value in @prev on subsequent | |
1123 | * invocations for reference counting, or use mem_cgroup_iter_break() | |
1124 | * to cancel a hierarchy walk before the round-trip is complete. | |
1125 | * | |
05bdc520 ML |
1126 | * Reclaimers can specify a node in @reclaim to divide up the memcgs |
1127 | * in the hierarchy among all concurrent reclaimers operating on the | |
1128 | * same node. | |
5660048c | 1129 | */ |
694fbc0f | 1130 | struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, |
5660048c | 1131 | struct mem_cgroup *prev, |
694fbc0f | 1132 | struct mem_cgroup_reclaim_cookie *reclaim) |
14067bb3 | 1133 | { |
3f649ab7 | 1134 | struct mem_cgroup_reclaim_iter *iter; |
5ac8fb31 | 1135 | struct cgroup_subsys_state *css = NULL; |
9f3a0d09 | 1136 | struct mem_cgroup *memcg = NULL; |
5ac8fb31 | 1137 | struct mem_cgroup *pos = NULL; |
711d3d2c | 1138 | |
694fbc0f AM |
1139 | if (mem_cgroup_disabled()) |
1140 | return NULL; | |
5660048c | 1141 | |
9f3a0d09 JW |
1142 | if (!root) |
1143 | root = root_mem_cgroup; | |
7d74b06f | 1144 | |
542f85f9 | 1145 | rcu_read_lock(); |
5f578161 | 1146 | |
5ac8fb31 | 1147 | if (reclaim) { |
ef8f2327 | 1148 | struct mem_cgroup_per_node *mz; |
5ac8fb31 | 1149 | |
a3747b53 | 1150 | mz = root->nodeinfo[reclaim->pgdat->node_id]; |
9da83f3f | 1151 | iter = &mz->iter; |
5ac8fb31 | 1152 | |
a9320aae WY |
1153 | /* |
1154 | * On start, join the current reclaim iteration cycle. | |
1155 | * Exit when a concurrent walker completes it. | |
1156 | */ | |
1157 | if (!prev) | |
1158 | reclaim->generation = iter->generation; | |
1159 | else if (reclaim->generation != iter->generation) | |
5ac8fb31 JW |
1160 | goto out_unlock; |
1161 | ||
6df38689 | 1162 | while (1) { |
4db0c3c2 | 1163 | pos = READ_ONCE(iter->position); |
6df38689 VD |
1164 | if (!pos || css_tryget(&pos->css)) |
1165 | break; | |
5ac8fb31 | 1166 | /* |
6df38689 VD |
1167 | * css reference reached zero, so iter->position will |
1168 | * be cleared by ->css_released. However, we should not | |
1169 | * rely on this happening soon, because ->css_released | |
1170 | * is called from a work queue, and by busy-waiting we | |
1171 | * might block it. So we clear iter->position right | |
1172 | * away. | |
5ac8fb31 | 1173 | */ |
6df38689 VD |
1174 | (void)cmpxchg(&iter->position, pos, NULL); |
1175 | } | |
89d8330c WY |
1176 | } else if (prev) { |
1177 | pos = prev; | |
5ac8fb31 JW |
1178 | } |
1179 | ||
1180 | if (pos) | |
1181 | css = &pos->css; | |
1182 | ||
1183 | for (;;) { | |
1184 | css = css_next_descendant_pre(css, &root->css); | |
1185 | if (!css) { | |
1186 | /* | |
1187 | * Reclaimers share the hierarchy walk, and a | |
1188 | * new one might jump in right at the end of | |
1189 | * the hierarchy - make sure they see at least | |
1190 | * one group and restart from the beginning. | |
1191 | */ | |
1192 | if (!prev) | |
1193 | continue; | |
1194 | break; | |
527a5ec9 | 1195 | } |
7d74b06f | 1196 | |
5ac8fb31 JW |
1197 | /* |
1198 | * Verify the css and acquire a reference. The root | |
1199 | * is provided by the caller, so we know it's alive | |
1200 | * and kicking, and don't take an extra reference. | |
1201 | */ | |
41555dad WY |
1202 | if (css == &root->css || css_tryget(css)) { |
1203 | memcg = mem_cgroup_from_css(css); | |
0b8f73e1 | 1204 | break; |
41555dad | 1205 | } |
9f3a0d09 | 1206 | } |
5ac8fb31 JW |
1207 | |
1208 | if (reclaim) { | |
5ac8fb31 | 1209 | /* |
6df38689 VD |
1210 | * The position could have already been updated by a competing |
1211 | * thread, so check that the value hasn't changed since we read | |
1212 | * it to avoid reclaiming from the same cgroup twice. | |
5ac8fb31 | 1213 | */ |
6df38689 VD |
1214 | (void)cmpxchg(&iter->position, pos, memcg); |
1215 | ||
5ac8fb31 JW |
1216 | if (pos) |
1217 | css_put(&pos->css); | |
1218 | ||
1219 | if (!memcg) | |
1220 | iter->generation++; | |
9f3a0d09 | 1221 | } |
5ac8fb31 | 1222 | |
542f85f9 MH |
1223 | out_unlock: |
1224 | rcu_read_unlock(); | |
c40046f3 MH |
1225 | if (prev && prev != root) |
1226 | css_put(&prev->css); | |
1227 | ||
9f3a0d09 | 1228 | return memcg; |
14067bb3 | 1229 | } |
7d74b06f | 1230 | |
5660048c JW |
1231 | /** |
1232 | * mem_cgroup_iter_break - abort a hierarchy walk prematurely | |
1233 | * @root: hierarchy root | |
1234 | * @prev: last visited hierarchy member as returned by mem_cgroup_iter() | |
1235 | */ | |
1236 | void mem_cgroup_iter_break(struct mem_cgroup *root, | |
1237 | struct mem_cgroup *prev) | |
9f3a0d09 JW |
1238 | { |
1239 | if (!root) | |
1240 | root = root_mem_cgroup; | |
1241 | if (prev && prev != root) | |
1242 | css_put(&prev->css); | |
1243 | } | |
7d74b06f | 1244 | |
54a83d6b MC |
1245 | static void __invalidate_reclaim_iterators(struct mem_cgroup *from, |
1246 | struct mem_cgroup *dead_memcg) | |
6df38689 | 1247 | { |
6df38689 | 1248 | struct mem_cgroup_reclaim_iter *iter; |
ef8f2327 MG |
1249 | struct mem_cgroup_per_node *mz; |
1250 | int nid; | |
6df38689 | 1251 | |
54a83d6b | 1252 | for_each_node(nid) { |
a3747b53 | 1253 | mz = from->nodeinfo[nid]; |
9da83f3f YS |
1254 | iter = &mz->iter; |
1255 | cmpxchg(&iter->position, dead_memcg, NULL); | |
6df38689 VD |
1256 | } |
1257 | } | |
1258 | ||
54a83d6b MC |
1259 | static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg) |
1260 | { | |
1261 | struct mem_cgroup *memcg = dead_memcg; | |
1262 | struct mem_cgroup *last; | |
1263 | ||
1264 | do { | |
1265 | __invalidate_reclaim_iterators(memcg, dead_memcg); | |
1266 | last = memcg; | |
1267 | } while ((memcg = parent_mem_cgroup(memcg))); | |
1268 | ||
1269 | /* | |
b8dd3ee9 | 1270 | * When cgroup1 non-hierarchy mode is used, |
54a83d6b MC |
1271 | * parent_mem_cgroup() does not walk all the way up to the |
1272 | * cgroup root (root_mem_cgroup). So we have to handle | |
1273 | * dead_memcg from cgroup root separately. | |
1274 | */ | |
7848ed62 | 1275 | if (!mem_cgroup_is_root(last)) |
54a83d6b MC |
1276 | __invalidate_reclaim_iterators(root_mem_cgroup, |
1277 | dead_memcg); | |
1278 | } | |
1279 | ||
7c5f64f8 VD |
1280 | /** |
1281 | * mem_cgroup_scan_tasks - iterate over tasks of a memory cgroup hierarchy | |
1282 | * @memcg: hierarchy root | |
1283 | * @fn: function to call for each task | |
1284 | * @arg: argument passed to @fn | |
1285 | * | |
1286 | * This function iterates over tasks attached to @memcg or to any of its | |
1287 | * descendants and calls @fn for each task. If @fn returns a non-zero | |
025b7799 Z |
1288 | * value, the function breaks the iteration loop. Otherwise, it will iterate |
1289 | * over all tasks and return 0. | |
7c5f64f8 VD |
1290 | * |
1291 | * This function must not be called for the root memory cgroup. | |
1292 | */ | |
025b7799 Z |
1293 | void mem_cgroup_scan_tasks(struct mem_cgroup *memcg, |
1294 | int (*fn)(struct task_struct *, void *), void *arg) | |
7c5f64f8 VD |
1295 | { |
1296 | struct mem_cgroup *iter; | |
1297 | int ret = 0; | |
1298 | ||
7848ed62 | 1299 | BUG_ON(mem_cgroup_is_root(memcg)); |
7c5f64f8 VD |
1300 | |
1301 | for_each_mem_cgroup_tree(iter, memcg) { | |
1302 | struct css_task_iter it; | |
1303 | struct task_struct *task; | |
1304 | ||
f168a9a5 | 1305 | css_task_iter_start(&iter->css, CSS_TASK_ITER_PROCS, &it); |
7c5f64f8 VD |
1306 | while (!ret && (task = css_task_iter_next(&it))) |
1307 | ret = fn(task, arg); | |
1308 | css_task_iter_end(&it); | |
1309 | if (ret) { | |
1310 | mem_cgroup_iter_break(memcg, iter); | |
1311 | break; | |
1312 | } | |
1313 | } | |
7c5f64f8 VD |
1314 | } |
1315 | ||
6168d0da | 1316 | #ifdef CONFIG_DEBUG_VM |
e809c3fe | 1317 | void lruvec_memcg_debug(struct lruvec *lruvec, struct folio *folio) |
6168d0da AS |
1318 | { |
1319 | struct mem_cgroup *memcg; | |
1320 | ||
1321 | if (mem_cgroup_disabled()) | |
1322 | return; | |
1323 | ||
e809c3fe | 1324 | memcg = folio_memcg(folio); |
6168d0da AS |
1325 | |
1326 | if (!memcg) | |
7848ed62 | 1327 | VM_BUG_ON_FOLIO(!mem_cgroup_is_root(lruvec_memcg(lruvec)), folio); |
6168d0da | 1328 | else |
e809c3fe | 1329 | VM_BUG_ON_FOLIO(lruvec_memcg(lruvec) != memcg, folio); |
6168d0da AS |
1330 | } |
1331 | #endif | |
1332 | ||
6168d0da | 1333 | /** |
e809c3fe MWO |
1334 | * folio_lruvec_lock - Lock the lruvec for a folio. |
1335 | * @folio: Pointer to the folio. | |
6168d0da | 1336 | * |
d7e3aba5 | 1337 | * These functions are safe to use under any of the following conditions: |
e809c3fe MWO |
1338 | * - folio locked |
1339 | * - folio_test_lru false | |
1340 | * - folio_memcg_lock() | |
1341 | * - folio frozen (refcount of 0) | |
1342 | * | |
1343 | * Return: The lruvec this folio is on with its lock held. | |
6168d0da | 1344 | */ |
e809c3fe | 1345 | struct lruvec *folio_lruvec_lock(struct folio *folio) |
6168d0da | 1346 | { |
e809c3fe | 1347 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1348 | |
6168d0da | 1349 | spin_lock(&lruvec->lru_lock); |
e809c3fe | 1350 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1351 | |
1352 | return lruvec; | |
1353 | } | |
1354 | ||
e809c3fe MWO |
1355 | /** |
1356 | * folio_lruvec_lock_irq - Lock the lruvec for a folio. | |
1357 | * @folio: Pointer to the folio. | |
1358 | * | |
1359 | * These functions are safe to use under any of the following conditions: | |
1360 | * - folio locked | |
1361 | * - folio_test_lru false | |
1362 | * - folio_memcg_lock() | |
1363 | * - folio frozen (refcount of 0) | |
1364 | * | |
1365 | * Return: The lruvec this folio is on with its lock held and interrupts | |
1366 | * disabled. | |
1367 | */ | |
1368 | struct lruvec *folio_lruvec_lock_irq(struct folio *folio) | |
6168d0da | 1369 | { |
e809c3fe | 1370 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1371 | |
6168d0da | 1372 | spin_lock_irq(&lruvec->lru_lock); |
e809c3fe | 1373 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1374 | |
1375 | return lruvec; | |
1376 | } | |
1377 | ||
e809c3fe MWO |
1378 | /** |
1379 | * folio_lruvec_lock_irqsave - Lock the lruvec for a folio. | |
1380 | * @folio: Pointer to the folio. | |
1381 | * @flags: Pointer to irqsave flags. | |
1382 | * | |
1383 | * These functions are safe to use under any of the following conditions: | |
1384 | * - folio locked | |
1385 | * - folio_test_lru false | |
1386 | * - folio_memcg_lock() | |
1387 | * - folio frozen (refcount of 0) | |
1388 | * | |
1389 | * Return: The lruvec this folio is on with its lock held and interrupts | |
1390 | * disabled. | |
1391 | */ | |
1392 | struct lruvec *folio_lruvec_lock_irqsave(struct folio *folio, | |
1393 | unsigned long *flags) | |
6168d0da | 1394 | { |
e809c3fe | 1395 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1396 | |
6168d0da | 1397 | spin_lock_irqsave(&lruvec->lru_lock, *flags); |
e809c3fe | 1398 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1399 | |
1400 | return lruvec; | |
1401 | } | |
1402 | ||
925b7673 | 1403 | /** |
fa9add64 HD |
1404 | * mem_cgroup_update_lru_size - account for adding or removing an lru page |
1405 | * @lruvec: mem_cgroup per zone lru vector | |
1406 | * @lru: index of lru list the page is sitting on | |
b4536f0c | 1407 | * @zid: zone id of the accounted pages |
fa9add64 | 1408 | * @nr_pages: positive when adding or negative when removing |
925b7673 | 1409 | * |
ca707239 | 1410 | * This function must be called under lru_lock, just before a page is added |
07ca7606 | 1411 | * to or just after a page is removed from an lru list. |
3f58a829 | 1412 | */ |
fa9add64 | 1413 | void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, |
b4536f0c | 1414 | int zid, int nr_pages) |
3f58a829 | 1415 | { |
ef8f2327 | 1416 | struct mem_cgroup_per_node *mz; |
fa9add64 | 1417 | unsigned long *lru_size; |
ca707239 | 1418 | long size; |
3f58a829 MK |
1419 | |
1420 | if (mem_cgroup_disabled()) | |
1421 | return; | |
1422 | ||
ef8f2327 | 1423 | mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); |
b4536f0c | 1424 | lru_size = &mz->lru_zone_size[zid][lru]; |
ca707239 HD |
1425 | |
1426 | if (nr_pages < 0) | |
1427 | *lru_size += nr_pages; | |
1428 | ||
1429 | size = *lru_size; | |
b4536f0c MH |
1430 | if (WARN_ONCE(size < 0, |
1431 | "%s(%p, %d, %d): lru_size %ld\n", | |
1432 | __func__, lruvec, lru, nr_pages, size)) { | |
ca707239 HD |
1433 | VM_BUG_ON(1); |
1434 | *lru_size = 0; | |
1435 | } | |
1436 | ||
1437 | if (nr_pages > 0) | |
1438 | *lru_size += nr_pages; | |
08e552c6 | 1439 | } |
544122e5 | 1440 | |
19942822 | 1441 | /** |
9d11ea9f | 1442 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
dad7557e | 1443 | * @memcg: the memory cgroup |
19942822 | 1444 | * |
9d11ea9f | 1445 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1446 | * pages. |
19942822 | 1447 | */ |
c0ff4b85 | 1448 | static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) |
19942822 | 1449 | { |
3e32cb2e JW |
1450 | unsigned long margin = 0; |
1451 | unsigned long count; | |
1452 | unsigned long limit; | |
9d11ea9f | 1453 | |
3e32cb2e | 1454 | count = page_counter_read(&memcg->memory); |
bbec2e15 | 1455 | limit = READ_ONCE(memcg->memory.max); |
3e32cb2e JW |
1456 | if (count < limit) |
1457 | margin = limit - count; | |
1458 | ||
7941d214 | 1459 | if (do_memsw_account()) { |
3e32cb2e | 1460 | count = page_counter_read(&memcg->memsw); |
bbec2e15 | 1461 | limit = READ_ONCE(memcg->memsw.max); |
1c4448ed | 1462 | if (count < limit) |
3e32cb2e | 1463 | margin = min(margin, limit - count); |
cbedbac3 LR |
1464 | else |
1465 | margin = 0; | |
3e32cb2e JW |
1466 | } |
1467 | ||
1468 | return margin; | |
19942822 JW |
1469 | } |
1470 | ||
32047e2a | 1471 | /* |
bdcbb659 | 1472 | * A routine for checking "mem" is under move_account() or not. |
32047e2a | 1473 | * |
bdcbb659 QH |
1474 | * Checking a cgroup is mc.from or mc.to or under hierarchy of |
1475 | * moving cgroups. This is for waiting at high-memory pressure | |
1476 | * caused by "move". | |
32047e2a | 1477 | */ |
c0ff4b85 | 1478 | static bool mem_cgroup_under_move(struct mem_cgroup *memcg) |
4b534334 | 1479 | { |
2bd9bb20 KH |
1480 | struct mem_cgroup *from; |
1481 | struct mem_cgroup *to; | |
4b534334 | 1482 | bool ret = false; |
2bd9bb20 KH |
1483 | /* |
1484 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1485 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1486 | */ | |
1487 | spin_lock(&mc.lock); | |
1488 | from = mc.from; | |
1489 | to = mc.to; | |
1490 | if (!from) | |
1491 | goto unlock; | |
3e92041d | 1492 | |
2314b42d JW |
1493 | ret = mem_cgroup_is_descendant(from, memcg) || |
1494 | mem_cgroup_is_descendant(to, memcg); | |
2bd9bb20 KH |
1495 | unlock: |
1496 | spin_unlock(&mc.lock); | |
4b534334 KH |
1497 | return ret; |
1498 | } | |
1499 | ||
c0ff4b85 | 1500 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) |
4b534334 KH |
1501 | { |
1502 | if (mc.moving_task && current != mc.moving_task) { | |
c0ff4b85 | 1503 | if (mem_cgroup_under_move(memcg)) { |
4b534334 KH |
1504 | DEFINE_WAIT(wait); |
1505 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1506 | /* moving charge context might have finished. */ | |
1507 | if (mc.moving_task) | |
1508 | schedule(); | |
1509 | finish_wait(&mc.waitq, &wait); | |
1510 | return true; | |
1511 | } | |
1512 | } | |
1513 | return false; | |
1514 | } | |
1515 | ||
5f9a4f4a MS |
1516 | struct memory_stat { |
1517 | const char *name; | |
5f9a4f4a MS |
1518 | unsigned int idx; |
1519 | }; | |
1520 | ||
57b2847d | 1521 | static const struct memory_stat memory_stats[] = { |
fff66b79 MS |
1522 | { "anon", NR_ANON_MAPPED }, |
1523 | { "file", NR_FILE_PAGES }, | |
a8c49af3 | 1524 | { "kernel", MEMCG_KMEM }, |
fff66b79 MS |
1525 | { "kernel_stack", NR_KERNEL_STACK_KB }, |
1526 | { "pagetables", NR_PAGETABLE }, | |
ebc97a52 | 1527 | { "sec_pagetables", NR_SECONDARY_PAGETABLE }, |
fff66b79 MS |
1528 | { "percpu", MEMCG_PERCPU_B }, |
1529 | { "sock", MEMCG_SOCK }, | |
4e5aa1f4 | 1530 | { "vmalloc", MEMCG_VMALLOC }, |
fff66b79 | 1531 | { "shmem", NR_SHMEM }, |
f4840ccf JW |
1532 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
1533 | { "zswap", MEMCG_ZSWAP_B }, | |
1534 | { "zswapped", MEMCG_ZSWAPPED }, | |
1535 | #endif | |
fff66b79 MS |
1536 | { "file_mapped", NR_FILE_MAPPED }, |
1537 | { "file_dirty", NR_FILE_DIRTY }, | |
1538 | { "file_writeback", NR_WRITEBACK }, | |
b6038942 SB |
1539 | #ifdef CONFIG_SWAP |
1540 | { "swapcached", NR_SWAPCACHE }, | |
1541 | #endif | |
5f9a4f4a | 1542 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
fff66b79 MS |
1543 | { "anon_thp", NR_ANON_THPS }, |
1544 | { "file_thp", NR_FILE_THPS }, | |
1545 | { "shmem_thp", NR_SHMEM_THPS }, | |
5f9a4f4a | 1546 | #endif |
fff66b79 MS |
1547 | { "inactive_anon", NR_INACTIVE_ANON }, |
1548 | { "active_anon", NR_ACTIVE_ANON }, | |
1549 | { "inactive_file", NR_INACTIVE_FILE }, | |
1550 | { "active_file", NR_ACTIVE_FILE }, | |
1551 | { "unevictable", NR_UNEVICTABLE }, | |
1552 | { "slab_reclaimable", NR_SLAB_RECLAIMABLE_B }, | |
1553 | { "slab_unreclaimable", NR_SLAB_UNRECLAIMABLE_B }, | |
5f9a4f4a MS |
1554 | |
1555 | /* The memory events */ | |
fff66b79 MS |
1556 | { "workingset_refault_anon", WORKINGSET_REFAULT_ANON }, |
1557 | { "workingset_refault_file", WORKINGSET_REFAULT_FILE }, | |
1558 | { "workingset_activate_anon", WORKINGSET_ACTIVATE_ANON }, | |
1559 | { "workingset_activate_file", WORKINGSET_ACTIVATE_FILE }, | |
1560 | { "workingset_restore_anon", WORKINGSET_RESTORE_ANON }, | |
1561 | { "workingset_restore_file", WORKINGSET_RESTORE_FILE }, | |
1562 | { "workingset_nodereclaim", WORKINGSET_NODERECLAIM }, | |
5f9a4f4a MS |
1563 | }; |
1564 | ||
ff841a06 | 1565 | /* The actual unit of the state item, not the same as the output unit */ |
fff66b79 MS |
1566 | static int memcg_page_state_unit(int item) |
1567 | { | |
1568 | switch (item) { | |
1569 | case MEMCG_PERCPU_B: | |
f4840ccf | 1570 | case MEMCG_ZSWAP_B: |
fff66b79 MS |
1571 | case NR_SLAB_RECLAIMABLE_B: |
1572 | case NR_SLAB_UNRECLAIMABLE_B: | |
ff841a06 YA |
1573 | return 1; |
1574 | case NR_KERNEL_STACK_KB: | |
1575 | return SZ_1K; | |
1576 | default: | |
1577 | return PAGE_SIZE; | |
1578 | } | |
1579 | } | |
1580 | ||
1581 | /* Translate stat items to the correct unit for memory.stat output */ | |
1582 | static int memcg_page_state_output_unit(int item) | |
1583 | { | |
1584 | /* | |
1585 | * Workingset state is actually in pages, but we export it to userspace | |
1586 | * as a scalar count of events, so special case it here. | |
1587 | */ | |
1588 | switch (item) { | |
fff66b79 MS |
1589 | case WORKINGSET_REFAULT_ANON: |
1590 | case WORKINGSET_REFAULT_FILE: | |
1591 | case WORKINGSET_ACTIVATE_ANON: | |
1592 | case WORKINGSET_ACTIVATE_FILE: | |
1593 | case WORKINGSET_RESTORE_ANON: | |
1594 | case WORKINGSET_RESTORE_FILE: | |
1595 | case WORKINGSET_NODERECLAIM: | |
1596 | return 1; | |
fff66b79 | 1597 | default: |
ff841a06 | 1598 | return memcg_page_state_unit(item); |
fff66b79 MS |
1599 | } |
1600 | } | |
1601 | ||
1602 | static inline unsigned long memcg_page_state_output(struct mem_cgroup *memcg, | |
1603 | int item) | |
1604 | { | |
ff841a06 YA |
1605 | return memcg_page_state(memcg, item) * |
1606 | memcg_page_state_output_unit(item); | |
1607 | } | |
1608 | ||
1609 | static inline unsigned long memcg_page_state_local_output( | |
1610 | struct mem_cgroup *memcg, int item) | |
1611 | { | |
1612 | return memcg_page_state_local(memcg, item) * | |
1613 | memcg_page_state_output_unit(item); | |
fff66b79 MS |
1614 | } |
1615 | ||
dddb44ff | 1616 | static void memcg_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) |
c8713d0b | 1617 | { |
c8713d0b | 1618 | int i; |
71cd3113 | 1619 | |
c8713d0b JW |
1620 | /* |
1621 | * Provide statistics on the state of the memory subsystem as | |
1622 | * well as cumulative event counters that show past behavior. | |
1623 | * | |
1624 | * This list is ordered following a combination of these gradients: | |
1625 | * 1) generic big picture -> specifics and details | |
1626 | * 2) reflecting userspace activity -> reflecting kernel heuristics | |
1627 | * | |
1628 | * Current memory state: | |
1629 | */ | |
fd25a9e0 | 1630 | mem_cgroup_flush_stats(); |
c8713d0b | 1631 | |
5f9a4f4a MS |
1632 | for (i = 0; i < ARRAY_SIZE(memory_stats); i++) { |
1633 | u64 size; | |
c8713d0b | 1634 | |
fff66b79 | 1635 | size = memcg_page_state_output(memcg, memory_stats[i].idx); |
5b42360c | 1636 | seq_buf_printf(s, "%s %llu\n", memory_stats[i].name, size); |
c8713d0b | 1637 | |
5f9a4f4a | 1638 | if (unlikely(memory_stats[i].idx == NR_SLAB_UNRECLAIMABLE_B)) { |
fff66b79 MS |
1639 | size += memcg_page_state_output(memcg, |
1640 | NR_SLAB_RECLAIMABLE_B); | |
5b42360c | 1641 | seq_buf_printf(s, "slab %llu\n", size); |
5f9a4f4a MS |
1642 | } |
1643 | } | |
c8713d0b JW |
1644 | |
1645 | /* Accumulated memory events */ | |
5b42360c | 1646 | seq_buf_printf(s, "pgscan %lu\n", |
c8713d0b | 1647 | memcg_events(memcg, PGSCAN_KSWAPD) + |
57e9cc50 JW |
1648 | memcg_events(memcg, PGSCAN_DIRECT) + |
1649 | memcg_events(memcg, PGSCAN_KHUGEPAGED)); | |
5b42360c | 1650 | seq_buf_printf(s, "pgsteal %lu\n", |
c8713d0b | 1651 | memcg_events(memcg, PGSTEAL_KSWAPD) + |
57e9cc50 JW |
1652 | memcg_events(memcg, PGSTEAL_DIRECT) + |
1653 | memcg_events(memcg, PGSTEAL_KHUGEPAGED)); | |
c8713d0b | 1654 | |
8278f1c7 SB |
1655 | for (i = 0; i < ARRAY_SIZE(memcg_vm_event_stat); i++) { |
1656 | if (memcg_vm_event_stat[i] == PGPGIN || | |
1657 | memcg_vm_event_stat[i] == PGPGOUT) | |
1658 | continue; | |
1659 | ||
5b42360c | 1660 | seq_buf_printf(s, "%s %lu\n", |
673520f8 QZ |
1661 | vm_event_name(memcg_vm_event_stat[i]), |
1662 | memcg_events(memcg, memcg_vm_event_stat[i])); | |
8278f1c7 | 1663 | } |
c8713d0b JW |
1664 | |
1665 | /* The above should easily fit into one page */ | |
5b42360c | 1666 | WARN_ON_ONCE(seq_buf_has_overflowed(s)); |
c8713d0b | 1667 | } |
71cd3113 | 1668 | |
dddb44ff YA |
1669 | static void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s); |
1670 | ||
1671 | static void memory_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) | |
1672 | { | |
1673 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
1674 | memcg_stat_format(memcg, s); | |
1675 | else | |
1676 | memcg1_stat_format(memcg, s); | |
1677 | WARN_ON_ONCE(seq_buf_has_overflowed(s)); | |
1678 | } | |
1679 | ||
e222432b | 1680 | /** |
f0c867d9 | 1681 | * mem_cgroup_print_oom_context: Print OOM information relevant to |
1682 | * memory controller. | |
e222432b BS |
1683 | * @memcg: The memory cgroup that went over limit |
1684 | * @p: Task that is going to be killed | |
1685 | * | |
1686 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1687 | * enabled | |
1688 | */ | |
f0c867d9 | 1689 | void mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p) |
e222432b | 1690 | { |
e222432b BS |
1691 | rcu_read_lock(); |
1692 | ||
f0c867d9 | 1693 | if (memcg) { |
1694 | pr_cont(",oom_memcg="); | |
1695 | pr_cont_cgroup_path(memcg->css.cgroup); | |
1696 | } else | |
1697 | pr_cont(",global_oom"); | |
2415b9f5 | 1698 | if (p) { |
f0c867d9 | 1699 | pr_cont(",task_memcg="); |
2415b9f5 | 1700 | pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id)); |
2415b9f5 | 1701 | } |
e222432b | 1702 | rcu_read_unlock(); |
f0c867d9 | 1703 | } |
1704 | ||
1705 | /** | |
1706 | * mem_cgroup_print_oom_meminfo: Print OOM memory information relevant to | |
1707 | * memory controller. | |
1708 | * @memcg: The memory cgroup that went over limit | |
1709 | */ | |
1710 | void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg) | |
1711 | { | |
68aaee14 TH |
1712 | /* Use static buffer, for the caller is holding oom_lock. */ |
1713 | static char buf[PAGE_SIZE]; | |
5b42360c | 1714 | struct seq_buf s; |
68aaee14 TH |
1715 | |
1716 | lockdep_assert_held(&oom_lock); | |
e222432b | 1717 | |
3e32cb2e JW |
1718 | pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n", |
1719 | K((u64)page_counter_read(&memcg->memory)), | |
15b42562 | 1720 | K((u64)READ_ONCE(memcg->memory.max)), memcg->memory.failcnt); |
c8713d0b JW |
1721 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
1722 | pr_info("swap: usage %llukB, limit %llukB, failcnt %lu\n", | |
1723 | K((u64)page_counter_read(&memcg->swap)), | |
32d087cd | 1724 | K((u64)READ_ONCE(memcg->swap.max)), memcg->swap.failcnt); |
c8713d0b JW |
1725 | else { |
1726 | pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n", | |
1727 | K((u64)page_counter_read(&memcg->memsw)), | |
1728 | K((u64)memcg->memsw.max), memcg->memsw.failcnt); | |
1729 | pr_info("kmem: usage %llukB, limit %llukB, failcnt %lu\n", | |
1730 | K((u64)page_counter_read(&memcg->kmem)), | |
1731 | K((u64)memcg->kmem.max), memcg->kmem.failcnt); | |
58cf188e | 1732 | } |
c8713d0b JW |
1733 | |
1734 | pr_info("Memory cgroup stats for "); | |
1735 | pr_cont_cgroup_path(memcg->css.cgroup); | |
1736 | pr_cont(":"); | |
5b42360c YA |
1737 | seq_buf_init(&s, buf, sizeof(buf)); |
1738 | memory_stat_format(memcg, &s); | |
1739 | seq_buf_do_printk(&s, KERN_INFO); | |
e222432b BS |
1740 | } |
1741 | ||
a63d83f4 DR |
1742 | /* |
1743 | * Return the memory (and swap, if configured) limit for a memcg. | |
1744 | */ | |
bbec2e15 | 1745 | unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg) |
a63d83f4 | 1746 | { |
8d387a5f WL |
1747 | unsigned long max = READ_ONCE(memcg->memory.max); |
1748 | ||
b94c4e94 | 1749 | if (do_memsw_account()) { |
8d387a5f WL |
1750 | if (mem_cgroup_swappiness(memcg)) { |
1751 | /* Calculate swap excess capacity from memsw limit */ | |
1752 | unsigned long swap = READ_ONCE(memcg->memsw.max) - max; | |
1753 | ||
1754 | max += min(swap, (unsigned long)total_swap_pages); | |
1755 | } | |
b94c4e94 JW |
1756 | } else { |
1757 | if (mem_cgroup_swappiness(memcg)) | |
1758 | max += min(READ_ONCE(memcg->swap.max), | |
1759 | (unsigned long)total_swap_pages); | |
9a5a8f19 | 1760 | } |
bbec2e15 | 1761 | return max; |
a63d83f4 DR |
1762 | } |
1763 | ||
9783aa99 CD |
1764 | unsigned long mem_cgroup_size(struct mem_cgroup *memcg) |
1765 | { | |
1766 | return page_counter_read(&memcg->memory); | |
1767 | } | |
1768 | ||
b6e6edcf | 1769 | static bool mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, |
19965460 | 1770 | int order) |
9cbb78bb | 1771 | { |
6e0fc46d DR |
1772 | struct oom_control oc = { |
1773 | .zonelist = NULL, | |
1774 | .nodemask = NULL, | |
2a966b77 | 1775 | .memcg = memcg, |
6e0fc46d DR |
1776 | .gfp_mask = gfp_mask, |
1777 | .order = order, | |
6e0fc46d | 1778 | }; |
1378b37d | 1779 | bool ret = true; |
9cbb78bb | 1780 | |
7775face TH |
1781 | if (mutex_lock_killable(&oom_lock)) |
1782 | return true; | |
1378b37d YS |
1783 | |
1784 | if (mem_cgroup_margin(memcg) >= (1 << order)) | |
1785 | goto unlock; | |
1786 | ||
7775face TH |
1787 | /* |
1788 | * A few threads which were not waiting at mutex_lock_killable() can | |
1789 | * fail to bail out. Therefore, check again after holding oom_lock. | |
1790 | */ | |
a4ebf1b6 | 1791 | ret = task_is_dying() || out_of_memory(&oc); |
1378b37d YS |
1792 | |
1793 | unlock: | |
dc56401f | 1794 | mutex_unlock(&oom_lock); |
7c5f64f8 | 1795 | return ret; |
9cbb78bb DR |
1796 | } |
1797 | ||
0608f43d | 1798 | static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, |
ef8f2327 | 1799 | pg_data_t *pgdat, |
0608f43d AM |
1800 | gfp_t gfp_mask, |
1801 | unsigned long *total_scanned) | |
1802 | { | |
1803 | struct mem_cgroup *victim = NULL; | |
1804 | int total = 0; | |
1805 | int loop = 0; | |
1806 | unsigned long excess; | |
1807 | unsigned long nr_scanned; | |
1808 | struct mem_cgroup_reclaim_cookie reclaim = { | |
ef8f2327 | 1809 | .pgdat = pgdat, |
0608f43d AM |
1810 | }; |
1811 | ||
3e32cb2e | 1812 | excess = soft_limit_excess(root_memcg); |
0608f43d AM |
1813 | |
1814 | while (1) { | |
1815 | victim = mem_cgroup_iter(root_memcg, victim, &reclaim); | |
1816 | if (!victim) { | |
1817 | loop++; | |
1818 | if (loop >= 2) { | |
1819 | /* | |
1820 | * If we have not been able to reclaim | |
1821 | * anything, it might because there are | |
1822 | * no reclaimable pages under this hierarchy | |
1823 | */ | |
1824 | if (!total) | |
1825 | break; | |
1826 | /* | |
1827 | * We want to do more targeted reclaim. | |
1828 | * excess >> 2 is not to excessive so as to | |
1829 | * reclaim too much, nor too less that we keep | |
1830 | * coming back to reclaim from this cgroup | |
1831 | */ | |
1832 | if (total >= (excess >> 2) || | |
1833 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) | |
1834 | break; | |
1835 | } | |
1836 | continue; | |
1837 | } | |
a9dd0a83 | 1838 | total += mem_cgroup_shrink_node(victim, gfp_mask, false, |
ef8f2327 | 1839 | pgdat, &nr_scanned); |
0608f43d | 1840 | *total_scanned += nr_scanned; |
3e32cb2e | 1841 | if (!soft_limit_excess(root_memcg)) |
0608f43d | 1842 | break; |
6d61ef40 | 1843 | } |
0608f43d AM |
1844 | mem_cgroup_iter_break(root_memcg, victim); |
1845 | return total; | |
6d61ef40 BS |
1846 | } |
1847 | ||
0056f4e6 JW |
1848 | #ifdef CONFIG_LOCKDEP |
1849 | static struct lockdep_map memcg_oom_lock_dep_map = { | |
1850 | .name = "memcg_oom_lock", | |
1851 | }; | |
1852 | #endif | |
1853 | ||
fb2a6fc5 JW |
1854 | static DEFINE_SPINLOCK(memcg_oom_lock); |
1855 | ||
867578cb KH |
1856 | /* |
1857 | * Check OOM-Killer is already running under our hierarchy. | |
1858 | * If someone is running, return false. | |
1859 | */ | |
fb2a6fc5 | 1860 | static bool mem_cgroup_oom_trylock(struct mem_cgroup *memcg) |
867578cb | 1861 | { |
79dfdacc | 1862 | struct mem_cgroup *iter, *failed = NULL; |
a636b327 | 1863 | |
fb2a6fc5 JW |
1864 | spin_lock(&memcg_oom_lock); |
1865 | ||
9f3a0d09 | 1866 | for_each_mem_cgroup_tree(iter, memcg) { |
23751be0 | 1867 | if (iter->oom_lock) { |
79dfdacc MH |
1868 | /* |
1869 | * this subtree of our hierarchy is already locked | |
1870 | * so we cannot give a lock. | |
1871 | */ | |
79dfdacc | 1872 | failed = iter; |
9f3a0d09 JW |
1873 | mem_cgroup_iter_break(memcg, iter); |
1874 | break; | |
23751be0 JW |
1875 | } else |
1876 | iter->oom_lock = true; | |
7d74b06f | 1877 | } |
867578cb | 1878 | |
fb2a6fc5 JW |
1879 | if (failed) { |
1880 | /* | |
1881 | * OK, we failed to lock the whole subtree so we have | |
1882 | * to clean up what we set up to the failing subtree | |
1883 | */ | |
1884 | for_each_mem_cgroup_tree(iter, memcg) { | |
1885 | if (iter == failed) { | |
1886 | mem_cgroup_iter_break(memcg, iter); | |
1887 | break; | |
1888 | } | |
1889 | iter->oom_lock = false; | |
79dfdacc | 1890 | } |
0056f4e6 JW |
1891 | } else |
1892 | mutex_acquire(&memcg_oom_lock_dep_map, 0, 1, _RET_IP_); | |
fb2a6fc5 JW |
1893 | |
1894 | spin_unlock(&memcg_oom_lock); | |
1895 | ||
1896 | return !failed; | |
a636b327 | 1897 | } |
0b7f569e | 1898 | |
fb2a6fc5 | 1899 | static void mem_cgroup_oom_unlock(struct mem_cgroup *memcg) |
0b7f569e | 1900 | { |
7d74b06f KH |
1901 | struct mem_cgroup *iter; |
1902 | ||
fb2a6fc5 | 1903 | spin_lock(&memcg_oom_lock); |
5facae4f | 1904 | mutex_release(&memcg_oom_lock_dep_map, _RET_IP_); |
c0ff4b85 | 1905 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc | 1906 | iter->oom_lock = false; |
fb2a6fc5 | 1907 | spin_unlock(&memcg_oom_lock); |
79dfdacc MH |
1908 | } |
1909 | ||
c0ff4b85 | 1910 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1911 | { |
1912 | struct mem_cgroup *iter; | |
1913 | ||
c2b42d3c | 1914 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1915 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1916 | iter->under_oom++; |
1917 | spin_unlock(&memcg_oom_lock); | |
79dfdacc MH |
1918 | } |
1919 | ||
c0ff4b85 | 1920 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1921 | { |
1922 | struct mem_cgroup *iter; | |
1923 | ||
867578cb | 1924 | /* |
f0953a1b | 1925 | * Be careful about under_oom underflows because a child memcg |
7a52d4d8 | 1926 | * could have been added after mem_cgroup_mark_under_oom. |
867578cb | 1927 | */ |
c2b42d3c | 1928 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1929 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1930 | if (iter->under_oom > 0) |
1931 | iter->under_oom--; | |
1932 | spin_unlock(&memcg_oom_lock); | |
0b7f569e KH |
1933 | } |
1934 | ||
867578cb KH |
1935 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1936 | ||
dc98df5a | 1937 | struct oom_wait_info { |
d79154bb | 1938 | struct mem_cgroup *memcg; |
ac6424b9 | 1939 | wait_queue_entry_t wait; |
dc98df5a KH |
1940 | }; |
1941 | ||
ac6424b9 | 1942 | static int memcg_oom_wake_function(wait_queue_entry_t *wait, |
dc98df5a KH |
1943 | unsigned mode, int sync, void *arg) |
1944 | { | |
d79154bb HD |
1945 | struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg; |
1946 | struct mem_cgroup *oom_wait_memcg; | |
dc98df5a KH |
1947 | struct oom_wait_info *oom_wait_info; |
1948 | ||
1949 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
d79154bb | 1950 | oom_wait_memcg = oom_wait_info->memcg; |
dc98df5a | 1951 | |
2314b42d JW |
1952 | if (!mem_cgroup_is_descendant(wake_memcg, oom_wait_memcg) && |
1953 | !mem_cgroup_is_descendant(oom_wait_memcg, wake_memcg)) | |
dc98df5a | 1954 | return 0; |
dc98df5a KH |
1955 | return autoremove_wake_function(wait, mode, sync, arg); |
1956 | } | |
1957 | ||
c0ff4b85 | 1958 | static void memcg_oom_recover(struct mem_cgroup *memcg) |
3c11ecf4 | 1959 | { |
c2b42d3c TH |
1960 | /* |
1961 | * For the following lockless ->under_oom test, the only required | |
1962 | * guarantee is that it must see the state asserted by an OOM when | |
1963 | * this function is called as a result of userland actions | |
1964 | * triggered by the notification of the OOM. This is trivially | |
1965 | * achieved by invoking mem_cgroup_mark_under_oom() before | |
1966 | * triggering notification. | |
1967 | */ | |
1968 | if (memcg && memcg->under_oom) | |
f4b90b70 | 1969 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg); |
3c11ecf4 KH |
1970 | } |
1971 | ||
becdf89d SB |
1972 | /* |
1973 | * Returns true if successfully killed one or more processes. Though in some | |
1974 | * corner cases it can return true even without killing any process. | |
1975 | */ | |
1976 | static bool mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order) | |
0b7f569e | 1977 | { |
becdf89d | 1978 | bool locked, ret; |
7056d3a3 | 1979 | |
29ef680a | 1980 | if (order > PAGE_ALLOC_COSTLY_ORDER) |
becdf89d | 1981 | return false; |
29ef680a | 1982 | |
7a1adfdd RG |
1983 | memcg_memory_event(memcg, MEMCG_OOM); |
1984 | ||
867578cb | 1985 | /* |
49426420 JW |
1986 | * We are in the middle of the charge context here, so we |
1987 | * don't want to block when potentially sitting on a callstack | |
1988 | * that holds all kinds of filesystem and mm locks. | |
1989 | * | |
29ef680a MH |
1990 | * cgroup1 allows disabling the OOM killer and waiting for outside |
1991 | * handling until the charge can succeed; remember the context and put | |
1992 | * the task to sleep at the end of the page fault when all locks are | |
1993 | * released. | |
49426420 | 1994 | * |
29ef680a MH |
1995 | * On the other hand, in-kernel OOM killer allows for an async victim |
1996 | * memory reclaim (oom_reaper) and that means that we are not solely | |
1997 | * relying on the oom victim to make a forward progress and we can | |
1998 | * invoke the oom killer here. | |
1999 | * | |
2000 | * Please note that mem_cgroup_out_of_memory might fail to find a | |
2001 | * victim and then we have to bail out from the charge path. | |
867578cb | 2002 | */ |
17c56de6 | 2003 | if (READ_ONCE(memcg->oom_kill_disable)) { |
becdf89d SB |
2004 | if (current->in_user_fault) { |
2005 | css_get(&memcg->css); | |
2006 | current->memcg_in_oom = memcg; | |
2007 | current->memcg_oom_gfp_mask = mask; | |
2008 | current->memcg_oom_order = order; | |
2009 | } | |
2010 | return false; | |
29ef680a MH |
2011 | } |
2012 | ||
7056d3a3 MH |
2013 | mem_cgroup_mark_under_oom(memcg); |
2014 | ||
2015 | locked = mem_cgroup_oom_trylock(memcg); | |
2016 | ||
2017 | if (locked) | |
2018 | mem_cgroup_oom_notify(memcg); | |
2019 | ||
2020 | mem_cgroup_unmark_under_oom(memcg); | |
becdf89d | 2021 | ret = mem_cgroup_out_of_memory(memcg, mask, order); |
7056d3a3 MH |
2022 | |
2023 | if (locked) | |
2024 | mem_cgroup_oom_unlock(memcg); | |
29ef680a | 2025 | |
7056d3a3 | 2026 | return ret; |
3812c8c8 JW |
2027 | } |
2028 | ||
2029 | /** | |
2030 | * mem_cgroup_oom_synchronize - complete memcg OOM handling | |
49426420 | 2031 | * @handle: actually kill/wait or just clean up the OOM state |
3812c8c8 | 2032 | * |
49426420 JW |
2033 | * This has to be called at the end of a page fault if the memcg OOM |
2034 | * handler was enabled. | |
3812c8c8 | 2035 | * |
49426420 | 2036 | * Memcg supports userspace OOM handling where failed allocations must |
3812c8c8 JW |
2037 | * sleep on a waitqueue until the userspace task resolves the |
2038 | * situation. Sleeping directly in the charge context with all kinds | |
2039 | * of locks held is not a good idea, instead we remember an OOM state | |
2040 | * in the task and mem_cgroup_oom_synchronize() has to be called at | |
49426420 | 2041 | * the end of the page fault to complete the OOM handling. |
3812c8c8 JW |
2042 | * |
2043 | * Returns %true if an ongoing memcg OOM situation was detected and | |
49426420 | 2044 | * completed, %false otherwise. |
3812c8c8 | 2045 | */ |
49426420 | 2046 | bool mem_cgroup_oom_synchronize(bool handle) |
3812c8c8 | 2047 | { |
626ebc41 | 2048 | struct mem_cgroup *memcg = current->memcg_in_oom; |
3812c8c8 | 2049 | struct oom_wait_info owait; |
49426420 | 2050 | bool locked; |
3812c8c8 JW |
2051 | |
2052 | /* OOM is global, do not handle */ | |
3812c8c8 | 2053 | if (!memcg) |
49426420 | 2054 | return false; |
3812c8c8 | 2055 | |
7c5f64f8 | 2056 | if (!handle) |
49426420 | 2057 | goto cleanup; |
3812c8c8 JW |
2058 | |
2059 | owait.memcg = memcg; | |
2060 | owait.wait.flags = 0; | |
2061 | owait.wait.func = memcg_oom_wake_function; | |
2062 | owait.wait.private = current; | |
2055da97 | 2063 | INIT_LIST_HEAD(&owait.wait.entry); |
867578cb | 2064 | |
3812c8c8 | 2065 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
49426420 JW |
2066 | mem_cgroup_mark_under_oom(memcg); |
2067 | ||
2068 | locked = mem_cgroup_oom_trylock(memcg); | |
2069 | ||
2070 | if (locked) | |
2071 | mem_cgroup_oom_notify(memcg); | |
2072 | ||
857f2139 HX |
2073 | schedule(); |
2074 | mem_cgroup_unmark_under_oom(memcg); | |
2075 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
49426420 | 2076 | |
18b1d18b | 2077 | if (locked) |
fb2a6fc5 | 2078 | mem_cgroup_oom_unlock(memcg); |
49426420 | 2079 | cleanup: |
626ebc41 | 2080 | current->memcg_in_oom = NULL; |
3812c8c8 | 2081 | css_put(&memcg->css); |
867578cb | 2082 | return true; |
0b7f569e KH |
2083 | } |
2084 | ||
3d8b38eb RG |
2085 | /** |
2086 | * mem_cgroup_get_oom_group - get a memory cgroup to clean up after OOM | |
2087 | * @victim: task to be killed by the OOM killer | |
2088 | * @oom_domain: memcg in case of memcg OOM, NULL in case of system-wide OOM | |
2089 | * | |
2090 | * Returns a pointer to a memory cgroup, which has to be cleaned up | |
2091 | * by killing all belonging OOM-killable tasks. | |
2092 | * | |
2093 | * Caller has to call mem_cgroup_put() on the returned non-NULL memcg. | |
2094 | */ | |
2095 | struct mem_cgroup *mem_cgroup_get_oom_group(struct task_struct *victim, | |
2096 | struct mem_cgroup *oom_domain) | |
2097 | { | |
2098 | struct mem_cgroup *oom_group = NULL; | |
2099 | struct mem_cgroup *memcg; | |
2100 | ||
2101 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
2102 | return NULL; | |
2103 | ||
2104 | if (!oom_domain) | |
2105 | oom_domain = root_mem_cgroup; | |
2106 | ||
2107 | rcu_read_lock(); | |
2108 | ||
2109 | memcg = mem_cgroup_from_task(victim); | |
7848ed62 | 2110 | if (mem_cgroup_is_root(memcg)) |
3d8b38eb RG |
2111 | goto out; |
2112 | ||
48fe267c RG |
2113 | /* |
2114 | * If the victim task has been asynchronously moved to a different | |
2115 | * memory cgroup, we might end up killing tasks outside oom_domain. | |
2116 | * In this case it's better to ignore memory.group.oom. | |
2117 | */ | |
2118 | if (unlikely(!mem_cgroup_is_descendant(memcg, oom_domain))) | |
2119 | goto out; | |
2120 | ||
3d8b38eb RG |
2121 | /* |
2122 | * Traverse the memory cgroup hierarchy from the victim task's | |
2123 | * cgroup up to the OOMing cgroup (or root) to find the | |
2124 | * highest-level memory cgroup with oom.group set. | |
2125 | */ | |
2126 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
eaf7b66b | 2127 | if (READ_ONCE(memcg->oom_group)) |
3d8b38eb RG |
2128 | oom_group = memcg; |
2129 | ||
2130 | if (memcg == oom_domain) | |
2131 | break; | |
2132 | } | |
2133 | ||
2134 | if (oom_group) | |
2135 | css_get(&oom_group->css); | |
2136 | out: | |
2137 | rcu_read_unlock(); | |
2138 | ||
2139 | return oom_group; | |
2140 | } | |
2141 | ||
2142 | void mem_cgroup_print_oom_group(struct mem_cgroup *memcg) | |
2143 | { | |
2144 | pr_info("Tasks in "); | |
2145 | pr_cont_cgroup_path(memcg->css.cgroup); | |
2146 | pr_cont(" are going to be killed due to memory.oom.group set\n"); | |
2147 | } | |
2148 | ||
d7365e78 | 2149 | /** |
f70ad448 MWO |
2150 | * folio_memcg_lock - Bind a folio to its memcg. |
2151 | * @folio: The folio. | |
32047e2a | 2152 | * |
f70ad448 | 2153 | * This function prevents unlocked LRU folios from being moved to |
739f79fc JW |
2154 | * another cgroup. |
2155 | * | |
f70ad448 MWO |
2156 | * It ensures lifetime of the bound memcg. The caller is responsible |
2157 | * for the lifetime of the folio. | |
d69b042f | 2158 | */ |
f70ad448 | 2159 | void folio_memcg_lock(struct folio *folio) |
89c06bd5 KH |
2160 | { |
2161 | struct mem_cgroup *memcg; | |
6de22619 | 2162 | unsigned long flags; |
89c06bd5 | 2163 | |
6de22619 JW |
2164 | /* |
2165 | * The RCU lock is held throughout the transaction. The fast | |
2166 | * path can get away without acquiring the memcg->move_lock | |
2167 | * because page moving starts with an RCU grace period. | |
739f79fc | 2168 | */ |
d7365e78 JW |
2169 | rcu_read_lock(); |
2170 | ||
2171 | if (mem_cgroup_disabled()) | |
1c824a68 | 2172 | return; |
89c06bd5 | 2173 | again: |
f70ad448 | 2174 | memcg = folio_memcg(folio); |
29833315 | 2175 | if (unlikely(!memcg)) |
1c824a68 | 2176 | return; |
d7365e78 | 2177 | |
20ad50d6 AS |
2178 | #ifdef CONFIG_PROVE_LOCKING |
2179 | local_irq_save(flags); | |
2180 | might_lock(&memcg->move_lock); | |
2181 | local_irq_restore(flags); | |
2182 | #endif | |
2183 | ||
bdcbb659 | 2184 | if (atomic_read(&memcg->moving_account) <= 0) |
1c824a68 | 2185 | return; |
89c06bd5 | 2186 | |
6de22619 | 2187 | spin_lock_irqsave(&memcg->move_lock, flags); |
f70ad448 | 2188 | if (memcg != folio_memcg(folio)) { |
6de22619 | 2189 | spin_unlock_irqrestore(&memcg->move_lock, flags); |
89c06bd5 KH |
2190 | goto again; |
2191 | } | |
6de22619 JW |
2192 | |
2193 | /* | |
1c824a68 JW |
2194 | * When charge migration first begins, we can have multiple |
2195 | * critical sections holding the fast-path RCU lock and one | |
2196 | * holding the slowpath move_lock. Track the task who has the | |
6c77b607 | 2197 | * move_lock for folio_memcg_unlock(). |
6de22619 JW |
2198 | */ |
2199 | memcg->move_lock_task = current; | |
2200 | memcg->move_lock_flags = flags; | |
89c06bd5 | 2201 | } |
f70ad448 | 2202 | |
f70ad448 | 2203 | static void __folio_memcg_unlock(struct mem_cgroup *memcg) |
89c06bd5 | 2204 | { |
6de22619 JW |
2205 | if (memcg && memcg->move_lock_task == current) { |
2206 | unsigned long flags = memcg->move_lock_flags; | |
2207 | ||
2208 | memcg->move_lock_task = NULL; | |
2209 | memcg->move_lock_flags = 0; | |
2210 | ||
2211 | spin_unlock_irqrestore(&memcg->move_lock, flags); | |
2212 | } | |
89c06bd5 | 2213 | |
d7365e78 | 2214 | rcu_read_unlock(); |
89c06bd5 | 2215 | } |
739f79fc JW |
2216 | |
2217 | /** | |
f70ad448 MWO |
2218 | * folio_memcg_unlock - Release the binding between a folio and its memcg. |
2219 | * @folio: The folio. | |
2220 | * | |
2221 | * This releases the binding created by folio_memcg_lock(). This does | |
2222 | * not change the accounting of this folio to its memcg, but it does | |
2223 | * permit others to change it. | |
739f79fc | 2224 | */ |
f70ad448 | 2225 | void folio_memcg_unlock(struct folio *folio) |
739f79fc | 2226 | { |
f70ad448 MWO |
2227 | __folio_memcg_unlock(folio_memcg(folio)); |
2228 | } | |
9da7b521 | 2229 | |
fead2b86 | 2230 | struct memcg_stock_pcp { |
56751146 | 2231 | local_lock_t stock_lock; |
fead2b86 MH |
2232 | struct mem_cgroup *cached; /* this never be root cgroup */ |
2233 | unsigned int nr_pages; | |
2234 | ||
bf4f0599 RG |
2235 | #ifdef CONFIG_MEMCG_KMEM |
2236 | struct obj_cgroup *cached_objcg; | |
68ac5b3c | 2237 | struct pglist_data *cached_pgdat; |
bf4f0599 | 2238 | unsigned int nr_bytes; |
68ac5b3c WL |
2239 | int nr_slab_reclaimable_b; |
2240 | int nr_slab_unreclaimable_b; | |
bf4f0599 RG |
2241 | #endif |
2242 | ||
cdec2e42 | 2243 | struct work_struct work; |
26fe6168 | 2244 | unsigned long flags; |
a0db00fc | 2245 | #define FLUSHING_CACHED_CHARGE 0 |
cdec2e42 | 2246 | }; |
56751146 SAS |
2247 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock) = { |
2248 | .stock_lock = INIT_LOCAL_LOCK(stock_lock), | |
2249 | }; | |
9f50fad6 | 2250 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 | 2251 | |
bf4f0599 | 2252 | #ifdef CONFIG_MEMCG_KMEM |
56751146 | 2253 | static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock); |
bf4f0599 RG |
2254 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, |
2255 | struct mem_cgroup *root_memcg); | |
a8c49af3 | 2256 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages); |
bf4f0599 RG |
2257 | |
2258 | #else | |
56751146 | 2259 | static inline struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) |
bf4f0599 | 2260 | { |
56751146 | 2261 | return NULL; |
bf4f0599 RG |
2262 | } |
2263 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, | |
2264 | struct mem_cgroup *root_memcg) | |
2265 | { | |
2266 | return false; | |
2267 | } | |
a8c49af3 YA |
2268 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) |
2269 | { | |
2270 | } | |
bf4f0599 RG |
2271 | #endif |
2272 | ||
a0956d54 SS |
2273 | /** |
2274 | * consume_stock: Try to consume stocked charge on this cpu. | |
2275 | * @memcg: memcg to consume from. | |
2276 | * @nr_pages: how many pages to charge. | |
2277 | * | |
2278 | * The charges will only happen if @memcg matches the current cpu's memcg | |
2279 | * stock, and at least @nr_pages are available in that stock. Failure to | |
2280 | * service an allocation will refill the stock. | |
2281 | * | |
2282 | * returns true if successful, false otherwise. | |
cdec2e42 | 2283 | */ |
a0956d54 | 2284 | static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
2285 | { |
2286 | struct memcg_stock_pcp *stock; | |
db2ba40c | 2287 | unsigned long flags; |
3e32cb2e | 2288 | bool ret = false; |
cdec2e42 | 2289 | |
a983b5eb | 2290 | if (nr_pages > MEMCG_CHARGE_BATCH) |
3e32cb2e | 2291 | return ret; |
a0956d54 | 2292 | |
56751146 | 2293 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
db2ba40c JW |
2294 | |
2295 | stock = this_cpu_ptr(&memcg_stock); | |
f785a8f2 | 2296 | if (memcg == READ_ONCE(stock->cached) && stock->nr_pages >= nr_pages) { |
a0956d54 | 2297 | stock->nr_pages -= nr_pages; |
3e32cb2e JW |
2298 | ret = true; |
2299 | } | |
db2ba40c | 2300 | |
56751146 | 2301 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
db2ba40c | 2302 | |
cdec2e42 KH |
2303 | return ret; |
2304 | } | |
2305 | ||
2306 | /* | |
3e32cb2e | 2307 | * Returns stocks cached in percpu and reset cached information. |
cdec2e42 KH |
2308 | */ |
2309 | static void drain_stock(struct memcg_stock_pcp *stock) | |
2310 | { | |
f785a8f2 | 2311 | struct mem_cgroup *old = READ_ONCE(stock->cached); |
cdec2e42 | 2312 | |
1a3e1f40 JW |
2313 | if (!old) |
2314 | return; | |
2315 | ||
11c9ea4e | 2316 | if (stock->nr_pages) { |
3e32cb2e | 2317 | page_counter_uncharge(&old->memory, stock->nr_pages); |
7941d214 | 2318 | if (do_memsw_account()) |
3e32cb2e | 2319 | page_counter_uncharge(&old->memsw, stock->nr_pages); |
11c9ea4e | 2320 | stock->nr_pages = 0; |
cdec2e42 | 2321 | } |
1a3e1f40 JW |
2322 | |
2323 | css_put(&old->css); | |
f785a8f2 | 2324 | WRITE_ONCE(stock->cached, NULL); |
cdec2e42 KH |
2325 | } |
2326 | ||
cdec2e42 KH |
2327 | static void drain_local_stock(struct work_struct *dummy) |
2328 | { | |
db2ba40c | 2329 | struct memcg_stock_pcp *stock; |
56751146 | 2330 | struct obj_cgroup *old = NULL; |
db2ba40c JW |
2331 | unsigned long flags; |
2332 | ||
72f0184c | 2333 | /* |
5c49cf9a MH |
2334 | * The only protection from cpu hotplug (memcg_hotplug_cpu_dead) vs. |
2335 | * drain_stock races is that we always operate on local CPU stock | |
2336 | * here with IRQ disabled | |
72f0184c | 2337 | */ |
56751146 | 2338 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
db2ba40c JW |
2339 | |
2340 | stock = this_cpu_ptr(&memcg_stock); | |
56751146 | 2341 | old = drain_obj_stock(stock); |
cdec2e42 | 2342 | drain_stock(stock); |
26fe6168 | 2343 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
db2ba40c | 2344 | |
56751146 SAS |
2345 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
2346 | if (old) | |
2347 | obj_cgroup_put(old); | |
cdec2e42 KH |
2348 | } |
2349 | ||
2350 | /* | |
3e32cb2e | 2351 | * Cache charges(val) to local per_cpu area. |
320cc51d | 2352 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 2353 | */ |
af9a3b69 | 2354 | static void __refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 | 2355 | { |
db2ba40c | 2356 | struct memcg_stock_pcp *stock; |
cdec2e42 | 2357 | |
db2ba40c | 2358 | stock = this_cpu_ptr(&memcg_stock); |
f785a8f2 | 2359 | if (READ_ONCE(stock->cached) != memcg) { /* reset if necessary */ |
cdec2e42 | 2360 | drain_stock(stock); |
1a3e1f40 | 2361 | css_get(&memcg->css); |
f785a8f2 | 2362 | WRITE_ONCE(stock->cached, memcg); |
cdec2e42 | 2363 | } |
11c9ea4e | 2364 | stock->nr_pages += nr_pages; |
db2ba40c | 2365 | |
a983b5eb | 2366 | if (stock->nr_pages > MEMCG_CHARGE_BATCH) |
475d0487 | 2367 | drain_stock(stock); |
af9a3b69 JW |
2368 | } |
2369 | ||
2370 | static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) | |
2371 | { | |
2372 | unsigned long flags; | |
475d0487 | 2373 | |
56751146 | 2374 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
af9a3b69 | 2375 | __refill_stock(memcg, nr_pages); |
56751146 | 2376 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
cdec2e42 KH |
2377 | } |
2378 | ||
2379 | /* | |
c0ff4b85 | 2380 | * Drains all per-CPU charge caches for given root_memcg resp. subtree |
6d3d6aa2 | 2381 | * of the hierarchy under it. |
cdec2e42 | 2382 | */ |
6d3d6aa2 | 2383 | static void drain_all_stock(struct mem_cgroup *root_memcg) |
cdec2e42 | 2384 | { |
26fe6168 | 2385 | int cpu, curcpu; |
d38144b7 | 2386 | |
6d3d6aa2 JW |
2387 | /* If someone's already draining, avoid adding running more workers. */ |
2388 | if (!mutex_trylock(&percpu_charge_mutex)) | |
2389 | return; | |
72f0184c MH |
2390 | /* |
2391 | * Notify other cpus that system-wide "drain" is running | |
2392 | * We do not care about races with the cpu hotplug because cpu down | |
2393 | * as well as workers from this path always operate on the local | |
2394 | * per-cpu data. CPU up doesn't touch memcg_stock at all. | |
2395 | */ | |
0790ed62 SAS |
2396 | migrate_disable(); |
2397 | curcpu = smp_processor_id(); | |
cdec2e42 KH |
2398 | for_each_online_cpu(cpu) { |
2399 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
c0ff4b85 | 2400 | struct mem_cgroup *memcg; |
e1a366be | 2401 | bool flush = false; |
26fe6168 | 2402 | |
e1a366be | 2403 | rcu_read_lock(); |
f785a8f2 | 2404 | memcg = READ_ONCE(stock->cached); |
e1a366be RG |
2405 | if (memcg && stock->nr_pages && |
2406 | mem_cgroup_is_descendant(memcg, root_memcg)) | |
2407 | flush = true; | |
27fb0956 | 2408 | else if (obj_stock_flush_required(stock, root_memcg)) |
bf4f0599 | 2409 | flush = true; |
e1a366be RG |
2410 | rcu_read_unlock(); |
2411 | ||
2412 | if (flush && | |
2413 | !test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { | |
d1a05b69 MH |
2414 | if (cpu == curcpu) |
2415 | drain_local_stock(&stock->work); | |
6a792697 | 2416 | else if (!cpu_is_isolated(cpu)) |
d1a05b69 MH |
2417 | schedule_work_on(cpu, &stock->work); |
2418 | } | |
cdec2e42 | 2419 | } |
0790ed62 | 2420 | migrate_enable(); |
9f50fad6 | 2421 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2422 | } |
2423 | ||
2cd21c89 JW |
2424 | static int memcg_hotplug_cpu_dead(unsigned int cpu) |
2425 | { | |
2426 | struct memcg_stock_pcp *stock; | |
a3d4c05a | 2427 | |
2cd21c89 JW |
2428 | stock = &per_cpu(memcg_stock, cpu); |
2429 | drain_stock(stock); | |
a3d4c05a | 2430 | |
308167fc | 2431 | return 0; |
cdec2e42 KH |
2432 | } |
2433 | ||
b3ff9291 CD |
2434 | static unsigned long reclaim_high(struct mem_cgroup *memcg, |
2435 | unsigned int nr_pages, | |
2436 | gfp_t gfp_mask) | |
f7e1cb6e | 2437 | { |
b3ff9291 CD |
2438 | unsigned long nr_reclaimed = 0; |
2439 | ||
f7e1cb6e | 2440 | do { |
e22c6ed9 JW |
2441 | unsigned long pflags; |
2442 | ||
d1663a90 JK |
2443 | if (page_counter_read(&memcg->memory) <= |
2444 | READ_ONCE(memcg->memory.high)) | |
f7e1cb6e | 2445 | continue; |
e22c6ed9 | 2446 | |
e27be240 | 2447 | memcg_memory_event(memcg, MEMCG_HIGH); |
e22c6ed9 JW |
2448 | |
2449 | psi_memstall_enter(&pflags); | |
b3ff9291 | 2450 | nr_reclaimed += try_to_free_mem_cgroup_pages(memcg, nr_pages, |
73b73bac | 2451 | gfp_mask, |
55ab834a | 2452 | MEMCG_RECLAIM_MAY_SWAP); |
e22c6ed9 | 2453 | psi_memstall_leave(&pflags); |
4bf17307 CD |
2454 | } while ((memcg = parent_mem_cgroup(memcg)) && |
2455 | !mem_cgroup_is_root(memcg)); | |
b3ff9291 CD |
2456 | |
2457 | return nr_reclaimed; | |
f7e1cb6e JW |
2458 | } |
2459 | ||
2460 | static void high_work_func(struct work_struct *work) | |
2461 | { | |
2462 | struct mem_cgroup *memcg; | |
2463 | ||
2464 | memcg = container_of(work, struct mem_cgroup, high_work); | |
a983b5eb | 2465 | reclaim_high(memcg, MEMCG_CHARGE_BATCH, GFP_KERNEL); |
f7e1cb6e JW |
2466 | } |
2467 | ||
0e4b01df CD |
2468 | /* |
2469 | * Clamp the maximum sleep time per allocation batch to 2 seconds. This is | |
2470 | * enough to still cause a significant slowdown in most cases, while still | |
2471 | * allowing diagnostics and tracing to proceed without becoming stuck. | |
2472 | */ | |
2473 | #define MEMCG_MAX_HIGH_DELAY_JIFFIES (2UL*HZ) | |
2474 | ||
2475 | /* | |
2476 | * When calculating the delay, we use these either side of the exponentiation to | |
2477 | * maintain precision and scale to a reasonable number of jiffies (see the table | |
2478 | * below. | |
2479 | * | |
2480 | * - MEMCG_DELAY_PRECISION_SHIFT: Extra precision bits while translating the | |
2481 | * overage ratio to a delay. | |
ac5ddd0f | 2482 | * - MEMCG_DELAY_SCALING_SHIFT: The number of bits to scale down the |
0e4b01df CD |
2483 | * proposed penalty in order to reduce to a reasonable number of jiffies, and |
2484 | * to produce a reasonable delay curve. | |
2485 | * | |
2486 | * MEMCG_DELAY_SCALING_SHIFT just happens to be a number that produces a | |
2487 | * reasonable delay curve compared to precision-adjusted overage, not | |
2488 | * penalising heavily at first, but still making sure that growth beyond the | |
2489 | * limit penalises misbehaviour cgroups by slowing them down exponentially. For | |
2490 | * example, with a high of 100 megabytes: | |
2491 | * | |
2492 | * +-------+------------------------+ | |
2493 | * | usage | time to allocate in ms | | |
2494 | * +-------+------------------------+ | |
2495 | * | 100M | 0 | | |
2496 | * | 101M | 6 | | |
2497 | * | 102M | 25 | | |
2498 | * | 103M | 57 | | |
2499 | * | 104M | 102 | | |
2500 | * | 105M | 159 | | |
2501 | * | 106M | 230 | | |
2502 | * | 107M | 313 | | |
2503 | * | 108M | 409 | | |
2504 | * | 109M | 518 | | |
2505 | * | 110M | 639 | | |
2506 | * | 111M | 774 | | |
2507 | * | 112M | 921 | | |
2508 | * | 113M | 1081 | | |
2509 | * | 114M | 1254 | | |
2510 | * | 115M | 1439 | | |
2511 | * | 116M | 1638 | | |
2512 | * | 117M | 1849 | | |
2513 | * | 118M | 2000 | | |
2514 | * | 119M | 2000 | | |
2515 | * | 120M | 2000 | | |
2516 | * +-------+------------------------+ | |
2517 | */ | |
2518 | #define MEMCG_DELAY_PRECISION_SHIFT 20 | |
2519 | #define MEMCG_DELAY_SCALING_SHIFT 14 | |
2520 | ||
8a5dbc65 | 2521 | static u64 calculate_overage(unsigned long usage, unsigned long high) |
b23afb93 | 2522 | { |
8a5dbc65 | 2523 | u64 overage; |
b23afb93 | 2524 | |
8a5dbc65 JK |
2525 | if (usage <= high) |
2526 | return 0; | |
e26733e0 | 2527 | |
8a5dbc65 JK |
2528 | /* |
2529 | * Prevent division by 0 in overage calculation by acting as if | |
2530 | * it was a threshold of 1 page | |
2531 | */ | |
2532 | high = max(high, 1UL); | |
9b8b1754 | 2533 | |
8a5dbc65 JK |
2534 | overage = usage - high; |
2535 | overage <<= MEMCG_DELAY_PRECISION_SHIFT; | |
2536 | return div64_u64(overage, high); | |
2537 | } | |
e26733e0 | 2538 | |
8a5dbc65 JK |
2539 | static u64 mem_find_max_overage(struct mem_cgroup *memcg) |
2540 | { | |
2541 | u64 overage, max_overage = 0; | |
e26733e0 | 2542 | |
8a5dbc65 JK |
2543 | do { |
2544 | overage = calculate_overage(page_counter_read(&memcg->memory), | |
d1663a90 | 2545 | READ_ONCE(memcg->memory.high)); |
8a5dbc65 | 2546 | max_overage = max(overage, max_overage); |
e26733e0 CD |
2547 | } while ((memcg = parent_mem_cgroup(memcg)) && |
2548 | !mem_cgroup_is_root(memcg)); | |
2549 | ||
8a5dbc65 JK |
2550 | return max_overage; |
2551 | } | |
2552 | ||
4b82ab4f JK |
2553 | static u64 swap_find_max_overage(struct mem_cgroup *memcg) |
2554 | { | |
2555 | u64 overage, max_overage = 0; | |
2556 | ||
2557 | do { | |
2558 | overage = calculate_overage(page_counter_read(&memcg->swap), | |
2559 | READ_ONCE(memcg->swap.high)); | |
2560 | if (overage) | |
2561 | memcg_memory_event(memcg, MEMCG_SWAP_HIGH); | |
2562 | max_overage = max(overage, max_overage); | |
2563 | } while ((memcg = parent_mem_cgroup(memcg)) && | |
2564 | !mem_cgroup_is_root(memcg)); | |
2565 | ||
2566 | return max_overage; | |
2567 | } | |
2568 | ||
8a5dbc65 JK |
2569 | /* |
2570 | * Get the number of jiffies that we should penalise a mischievous cgroup which | |
2571 | * is exceeding its memory.high by checking both it and its ancestors. | |
2572 | */ | |
2573 | static unsigned long calculate_high_delay(struct mem_cgroup *memcg, | |
2574 | unsigned int nr_pages, | |
2575 | u64 max_overage) | |
2576 | { | |
2577 | unsigned long penalty_jiffies; | |
2578 | ||
e26733e0 CD |
2579 | if (!max_overage) |
2580 | return 0; | |
0e4b01df CD |
2581 | |
2582 | /* | |
0e4b01df CD |
2583 | * We use overage compared to memory.high to calculate the number of |
2584 | * jiffies to sleep (penalty_jiffies). Ideally this value should be | |
2585 | * fairly lenient on small overages, and increasingly harsh when the | |
2586 | * memcg in question makes it clear that it has no intention of stopping | |
2587 | * its crazy behaviour, so we exponentially increase the delay based on | |
2588 | * overage amount. | |
2589 | */ | |
e26733e0 CD |
2590 | penalty_jiffies = max_overage * max_overage * HZ; |
2591 | penalty_jiffies >>= MEMCG_DELAY_PRECISION_SHIFT; | |
2592 | penalty_jiffies >>= MEMCG_DELAY_SCALING_SHIFT; | |
0e4b01df CD |
2593 | |
2594 | /* | |
2595 | * Factor in the task's own contribution to the overage, such that four | |
2596 | * N-sized allocations are throttled approximately the same as one | |
2597 | * 4N-sized allocation. | |
2598 | * | |
2599 | * MEMCG_CHARGE_BATCH pages is nominal, so work out how much smaller or | |
2600 | * larger the current charge patch is than that. | |
2601 | */ | |
ff144e69 | 2602 | return penalty_jiffies * nr_pages / MEMCG_CHARGE_BATCH; |
e26733e0 CD |
2603 | } |
2604 | ||
2605 | /* | |
2606 | * Scheduled by try_charge() to be executed from the userland return path | |
2607 | * and reclaims memory over the high limit. | |
2608 | */ | |
9ea9cb00 | 2609 | void mem_cgroup_handle_over_high(gfp_t gfp_mask) |
e26733e0 CD |
2610 | { |
2611 | unsigned long penalty_jiffies; | |
2612 | unsigned long pflags; | |
b3ff9291 | 2613 | unsigned long nr_reclaimed; |
e26733e0 | 2614 | unsigned int nr_pages = current->memcg_nr_pages_over_high; |
d977aa93 | 2615 | int nr_retries = MAX_RECLAIM_RETRIES; |
e26733e0 | 2616 | struct mem_cgroup *memcg; |
b3ff9291 | 2617 | bool in_retry = false; |
e26733e0 CD |
2618 | |
2619 | if (likely(!nr_pages)) | |
2620 | return; | |
2621 | ||
2622 | memcg = get_mem_cgroup_from_mm(current->mm); | |
e26733e0 CD |
2623 | current->memcg_nr_pages_over_high = 0; |
2624 | ||
b3ff9291 CD |
2625 | retry_reclaim: |
2626 | /* | |
2627 | * The allocating task should reclaim at least the batch size, but for | |
2628 | * subsequent retries we only want to do what's necessary to prevent oom | |
2629 | * or breaching resource isolation. | |
2630 | * | |
2631 | * This is distinct from memory.max or page allocator behaviour because | |
2632 | * memory.high is currently batched, whereas memory.max and the page | |
2633 | * allocator run every time an allocation is made. | |
2634 | */ | |
2635 | nr_reclaimed = reclaim_high(memcg, | |
2636 | in_retry ? SWAP_CLUSTER_MAX : nr_pages, | |
9ea9cb00 | 2637 | gfp_mask); |
b3ff9291 | 2638 | |
e26733e0 CD |
2639 | /* |
2640 | * memory.high is breached and reclaim is unable to keep up. Throttle | |
2641 | * allocators proactively to slow down excessive growth. | |
2642 | */ | |
8a5dbc65 JK |
2643 | penalty_jiffies = calculate_high_delay(memcg, nr_pages, |
2644 | mem_find_max_overage(memcg)); | |
0e4b01df | 2645 | |
4b82ab4f JK |
2646 | penalty_jiffies += calculate_high_delay(memcg, nr_pages, |
2647 | swap_find_max_overage(memcg)); | |
2648 | ||
ff144e69 JK |
2649 | /* |
2650 | * Clamp the max delay per usermode return so as to still keep the | |
2651 | * application moving forwards and also permit diagnostics, albeit | |
2652 | * extremely slowly. | |
2653 | */ | |
2654 | penalty_jiffies = min(penalty_jiffies, MEMCG_MAX_HIGH_DELAY_JIFFIES); | |
2655 | ||
0e4b01df CD |
2656 | /* |
2657 | * Don't sleep if the amount of jiffies this memcg owes us is so low | |
2658 | * that it's not even worth doing, in an attempt to be nice to those who | |
2659 | * go only a small amount over their memory.high value and maybe haven't | |
2660 | * been aggressively reclaimed enough yet. | |
2661 | */ | |
2662 | if (penalty_jiffies <= HZ / 100) | |
2663 | goto out; | |
2664 | ||
b3ff9291 CD |
2665 | /* |
2666 | * If reclaim is making forward progress but we're still over | |
2667 | * memory.high, we want to encourage that rather than doing allocator | |
2668 | * throttling. | |
2669 | */ | |
2670 | if (nr_reclaimed || nr_retries--) { | |
2671 | in_retry = true; | |
2672 | goto retry_reclaim; | |
2673 | } | |
2674 | ||
0e4b01df CD |
2675 | /* |
2676 | * If we exit early, we're guaranteed to die (since | |
2677 | * schedule_timeout_killable sets TASK_KILLABLE). This means we don't | |
2678 | * need to account for any ill-begotten jiffies to pay them off later. | |
2679 | */ | |
2680 | psi_memstall_enter(&pflags); | |
2681 | schedule_timeout_killable(penalty_jiffies); | |
2682 | psi_memstall_leave(&pflags); | |
2683 | ||
2684 | out: | |
2685 | css_put(&memcg->css); | |
b23afb93 TH |
2686 | } |
2687 | ||
c5c8b16b MS |
2688 | static int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask, |
2689 | unsigned int nr_pages) | |
8a9f3ccd | 2690 | { |
a983b5eb | 2691 | unsigned int batch = max(MEMCG_CHARGE_BATCH, nr_pages); |
d977aa93 | 2692 | int nr_retries = MAX_RECLAIM_RETRIES; |
6539cc05 | 2693 | struct mem_cgroup *mem_over_limit; |
3e32cb2e | 2694 | struct page_counter *counter; |
6539cc05 | 2695 | unsigned long nr_reclaimed; |
a4ebf1b6 | 2696 | bool passed_oom = false; |
73b73bac | 2697 | unsigned int reclaim_options = MEMCG_RECLAIM_MAY_SWAP; |
b70a2a21 | 2698 | bool drained = false; |
d6e103a7 | 2699 | bool raised_max_event = false; |
e22c6ed9 | 2700 | unsigned long pflags; |
a636b327 | 2701 | |
6539cc05 | 2702 | retry: |
b6b6cc72 | 2703 | if (consume_stock(memcg, nr_pages)) |
10d53c74 | 2704 | return 0; |
8a9f3ccd | 2705 | |
7941d214 | 2706 | if (!do_memsw_account() || |
6071ca52 JW |
2707 | page_counter_try_charge(&memcg->memsw, batch, &counter)) { |
2708 | if (page_counter_try_charge(&memcg->memory, batch, &counter)) | |
6539cc05 | 2709 | goto done_restock; |
7941d214 | 2710 | if (do_memsw_account()) |
3e32cb2e JW |
2711 | page_counter_uncharge(&memcg->memsw, batch); |
2712 | mem_over_limit = mem_cgroup_from_counter(counter, memory); | |
3fbe7244 | 2713 | } else { |
3e32cb2e | 2714 | mem_over_limit = mem_cgroup_from_counter(counter, memsw); |
73b73bac | 2715 | reclaim_options &= ~MEMCG_RECLAIM_MAY_SWAP; |
3fbe7244 | 2716 | } |
7a81b88c | 2717 | |
6539cc05 JW |
2718 | if (batch > nr_pages) { |
2719 | batch = nr_pages; | |
2720 | goto retry; | |
2721 | } | |
6d61ef40 | 2722 | |
89a28483 JW |
2723 | /* |
2724 | * Prevent unbounded recursion when reclaim operations need to | |
2725 | * allocate memory. This might exceed the limits temporarily, | |
2726 | * but we prefer facilitating memory reclaim and getting back | |
2727 | * under the limit over triggering OOM kills in these cases. | |
2728 | */ | |
2729 | if (unlikely(current->flags & PF_MEMALLOC)) | |
2730 | goto force; | |
2731 | ||
06b078fc JW |
2732 | if (unlikely(task_in_memcg_oom(current))) |
2733 | goto nomem; | |
2734 | ||
d0164adc | 2735 | if (!gfpflags_allow_blocking(gfp_mask)) |
6539cc05 | 2736 | goto nomem; |
4b534334 | 2737 | |
e27be240 | 2738 | memcg_memory_event(mem_over_limit, MEMCG_MAX); |
d6e103a7 | 2739 | raised_max_event = true; |
241994ed | 2740 | |
e22c6ed9 | 2741 | psi_memstall_enter(&pflags); |
b70a2a21 | 2742 | nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages, |
55ab834a | 2743 | gfp_mask, reclaim_options); |
e22c6ed9 | 2744 | psi_memstall_leave(&pflags); |
6539cc05 | 2745 | |
61e02c74 | 2746 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
6539cc05 | 2747 | goto retry; |
28c34c29 | 2748 | |
b70a2a21 | 2749 | if (!drained) { |
6d3d6aa2 | 2750 | drain_all_stock(mem_over_limit); |
b70a2a21 JW |
2751 | drained = true; |
2752 | goto retry; | |
2753 | } | |
2754 | ||
28c34c29 JW |
2755 | if (gfp_mask & __GFP_NORETRY) |
2756 | goto nomem; | |
6539cc05 JW |
2757 | /* |
2758 | * Even though the limit is exceeded at this point, reclaim | |
2759 | * may have been able to free some pages. Retry the charge | |
2760 | * before killing the task. | |
2761 | * | |
2762 | * Only for regular pages, though: huge pages are rather | |
2763 | * unlikely to succeed so close to the limit, and we fall back | |
2764 | * to regular pages anyway in case of failure. | |
2765 | */ | |
61e02c74 | 2766 | if (nr_reclaimed && nr_pages <= (1 << PAGE_ALLOC_COSTLY_ORDER)) |
6539cc05 JW |
2767 | goto retry; |
2768 | /* | |
2769 | * At task move, charge accounts can be doubly counted. So, it's | |
2770 | * better to wait until the end of task_move if something is going on. | |
2771 | */ | |
2772 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2773 | goto retry; | |
2774 | ||
9b130619 JW |
2775 | if (nr_retries--) |
2776 | goto retry; | |
2777 | ||
38d38493 | 2778 | if (gfp_mask & __GFP_RETRY_MAYFAIL) |
29ef680a MH |
2779 | goto nomem; |
2780 | ||
a4ebf1b6 VA |
2781 | /* Avoid endless loop for tasks bypassed by the oom killer */ |
2782 | if (passed_oom && task_is_dying()) | |
2783 | goto nomem; | |
6539cc05 | 2784 | |
29ef680a MH |
2785 | /* |
2786 | * keep retrying as long as the memcg oom killer is able to make | |
2787 | * a forward progress or bypass the charge if the oom killer | |
2788 | * couldn't make any progress. | |
2789 | */ | |
becdf89d SB |
2790 | if (mem_cgroup_oom(mem_over_limit, gfp_mask, |
2791 | get_order(nr_pages * PAGE_SIZE))) { | |
a4ebf1b6 | 2792 | passed_oom = true; |
d977aa93 | 2793 | nr_retries = MAX_RECLAIM_RETRIES; |
29ef680a | 2794 | goto retry; |
29ef680a | 2795 | } |
7a81b88c | 2796 | nomem: |
1461e8c2 SB |
2797 | /* |
2798 | * Memcg doesn't have a dedicated reserve for atomic | |
2799 | * allocations. But like the global atomic pool, we need to | |
2800 | * put the burden of reclaim on regular allocation requests | |
2801 | * and let these go through as privileged allocations. | |
2802 | */ | |
2803 | if (!(gfp_mask & (__GFP_NOFAIL | __GFP_HIGH))) | |
3168ecbe | 2804 | return -ENOMEM; |
10d53c74 | 2805 | force: |
d6e103a7 RG |
2806 | /* |
2807 | * If the allocation has to be enforced, don't forget to raise | |
2808 | * a MEMCG_MAX event. | |
2809 | */ | |
2810 | if (!raised_max_event) | |
2811 | memcg_memory_event(mem_over_limit, MEMCG_MAX); | |
2812 | ||
10d53c74 TH |
2813 | /* |
2814 | * The allocation either can't fail or will lead to more memory | |
2815 | * being freed very soon. Allow memory usage go over the limit | |
2816 | * temporarily by force charging it. | |
2817 | */ | |
2818 | page_counter_charge(&memcg->memory, nr_pages); | |
7941d214 | 2819 | if (do_memsw_account()) |
10d53c74 | 2820 | page_counter_charge(&memcg->memsw, nr_pages); |
10d53c74 TH |
2821 | |
2822 | return 0; | |
6539cc05 JW |
2823 | |
2824 | done_restock: | |
2825 | if (batch > nr_pages) | |
2826 | refill_stock(memcg, batch - nr_pages); | |
b23afb93 | 2827 | |
241994ed | 2828 | /* |
b23afb93 TH |
2829 | * If the hierarchy is above the normal consumption range, schedule |
2830 | * reclaim on returning to userland. We can perform reclaim here | |
71baba4b | 2831 | * if __GFP_RECLAIM but let's always punt for simplicity and so that |
b23afb93 TH |
2832 | * GFP_KERNEL can consistently be used during reclaim. @memcg is |
2833 | * not recorded as it most likely matches current's and won't | |
2834 | * change in the meantime. As high limit is checked again before | |
2835 | * reclaim, the cost of mismatch is negligible. | |
241994ed JW |
2836 | */ |
2837 | do { | |
4b82ab4f JK |
2838 | bool mem_high, swap_high; |
2839 | ||
2840 | mem_high = page_counter_read(&memcg->memory) > | |
2841 | READ_ONCE(memcg->memory.high); | |
2842 | swap_high = page_counter_read(&memcg->swap) > | |
2843 | READ_ONCE(memcg->swap.high); | |
2844 | ||
2845 | /* Don't bother a random interrupted task */ | |
086f694a | 2846 | if (!in_task()) { |
4b82ab4f | 2847 | if (mem_high) { |
f7e1cb6e JW |
2848 | schedule_work(&memcg->high_work); |
2849 | break; | |
2850 | } | |
4b82ab4f JK |
2851 | continue; |
2852 | } | |
2853 | ||
2854 | if (mem_high || swap_high) { | |
2855 | /* | |
2856 | * The allocating tasks in this cgroup will need to do | |
2857 | * reclaim or be throttled to prevent further growth | |
2858 | * of the memory or swap footprints. | |
2859 | * | |
2860 | * Target some best-effort fairness between the tasks, | |
2861 | * and distribute reclaim work and delay penalties | |
2862 | * based on how much each task is actually allocating. | |
2863 | */ | |
9516a18a | 2864 | current->memcg_nr_pages_over_high += batch; |
b23afb93 TH |
2865 | set_notify_resume(current); |
2866 | break; | |
2867 | } | |
241994ed | 2868 | } while ((memcg = parent_mem_cgroup(memcg))); |
10d53c74 | 2869 | |
c9afe31e SB |
2870 | if (current->memcg_nr_pages_over_high > MEMCG_CHARGE_BATCH && |
2871 | !(current->flags & PF_MEMALLOC) && | |
2872 | gfpflags_allow_blocking(gfp_mask)) { | |
9ea9cb00 | 2873 | mem_cgroup_handle_over_high(gfp_mask); |
c9afe31e | 2874 | } |
10d53c74 | 2875 | return 0; |
7a81b88c | 2876 | } |
8a9f3ccd | 2877 | |
c5c8b16b MS |
2878 | static inline int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, |
2879 | unsigned int nr_pages) | |
2880 | { | |
2881 | if (mem_cgroup_is_root(memcg)) | |
2882 | return 0; | |
2883 | ||
2884 | return try_charge_memcg(memcg, gfp_mask, nr_pages); | |
2885 | } | |
2886 | ||
4b569387 NP |
2887 | /** |
2888 | * mem_cgroup_cancel_charge() - cancel an uncommitted try_charge() call. | |
2889 | * @memcg: memcg previously charged. | |
2890 | * @nr_pages: number of pages previously charged. | |
2891 | */ | |
2892 | void mem_cgroup_cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) | |
a3032a2c | 2893 | { |
ce00a967 JW |
2894 | if (mem_cgroup_is_root(memcg)) |
2895 | return; | |
2896 | ||
3e32cb2e | 2897 | page_counter_uncharge(&memcg->memory, nr_pages); |
7941d214 | 2898 | if (do_memsw_account()) |
3e32cb2e | 2899 | page_counter_uncharge(&memcg->memsw, nr_pages); |
d01dd17f KH |
2900 | } |
2901 | ||
118f2875 | 2902 | static void commit_charge(struct folio *folio, struct mem_cgroup *memcg) |
0a31bc97 | 2903 | { |
118f2875 | 2904 | VM_BUG_ON_FOLIO(folio_memcg(folio), folio); |
0a31bc97 | 2905 | /* |
a5eb011a | 2906 | * Any of the following ensures page's memcg stability: |
0a31bc97 | 2907 | * |
a0b5b414 JW |
2908 | * - the page lock |
2909 | * - LRU isolation | |
6c77b607 | 2910 | * - folio_memcg_lock() |
a0b5b414 | 2911 | * - exclusive reference |
018ee47f | 2912 | * - mem_cgroup_trylock_pages() |
0a31bc97 | 2913 | */ |
118f2875 | 2914 | folio->memcg_data = (unsigned long)memcg; |
7a81b88c | 2915 | } |
66e1707b | 2916 | |
4b569387 NP |
2917 | /** |
2918 | * mem_cgroup_commit_charge - commit a previously successful try_charge(). | |
2919 | * @folio: folio to commit the charge to. | |
2920 | * @memcg: memcg previously charged. | |
2921 | */ | |
2922 | void mem_cgroup_commit_charge(struct folio *folio, struct mem_cgroup *memcg) | |
2923 | { | |
2924 | css_get(&memcg->css); | |
2925 | commit_charge(folio, memcg); | |
2926 | ||
2927 | local_irq_disable(); | |
2928 | mem_cgroup_charge_statistics(memcg, folio_nr_pages(folio)); | |
2929 | memcg_check_events(memcg, folio_nid(folio)); | |
2930 | local_irq_enable(); | |
2931 | } | |
2932 | ||
84c07d11 | 2933 | #ifdef CONFIG_MEMCG_KMEM |
41eb5df1 WL |
2934 | /* |
2935 | * The allocated objcg pointers array is not accounted directly. | |
2936 | * Moreover, it should not come from DMA buffer and is not readily | |
2937 | * reclaimable. So those GFP bits should be masked off. | |
2938 | */ | |
24948e3b RG |
2939 | #define OBJCGS_CLEAR_MASK (__GFP_DMA | __GFP_RECLAIMABLE | \ |
2940 | __GFP_ACCOUNT | __GFP_NOFAIL) | |
41eb5df1 | 2941 | |
a7ebf564 WL |
2942 | /* |
2943 | * mod_objcg_mlstate() may be called with irq enabled, so | |
2944 | * mod_memcg_lruvec_state() should be used. | |
2945 | */ | |
2946 | static inline void mod_objcg_mlstate(struct obj_cgroup *objcg, | |
2947 | struct pglist_data *pgdat, | |
2948 | enum node_stat_item idx, int nr) | |
2949 | { | |
2950 | struct mem_cgroup *memcg; | |
2951 | struct lruvec *lruvec; | |
2952 | ||
2953 | rcu_read_lock(); | |
2954 | memcg = obj_cgroup_memcg(objcg); | |
2955 | lruvec = mem_cgroup_lruvec(memcg, pgdat); | |
2956 | mod_memcg_lruvec_state(lruvec, idx, nr); | |
2957 | rcu_read_unlock(); | |
2958 | } | |
2959 | ||
4b5f8d9a VB |
2960 | int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, |
2961 | gfp_t gfp, bool new_slab) | |
10befea9 | 2962 | { |
4b5f8d9a | 2963 | unsigned int objects = objs_per_slab(s, slab); |
2e9bd483 | 2964 | unsigned long memcg_data; |
10befea9 RG |
2965 | void *vec; |
2966 | ||
41eb5df1 | 2967 | gfp &= ~OBJCGS_CLEAR_MASK; |
10befea9 | 2968 | vec = kcalloc_node(objects, sizeof(struct obj_cgroup *), gfp, |
4b5f8d9a | 2969 | slab_nid(slab)); |
10befea9 RG |
2970 | if (!vec) |
2971 | return -ENOMEM; | |
2972 | ||
2e9bd483 | 2973 | memcg_data = (unsigned long) vec | MEMCG_DATA_OBJCGS; |
4b5f8d9a | 2974 | if (new_slab) { |
2e9bd483 | 2975 | /* |
4b5f8d9a VB |
2976 | * If the slab is brand new and nobody can yet access its |
2977 | * memcg_data, no synchronization is required and memcg_data can | |
2978 | * be simply assigned. | |
2e9bd483 | 2979 | */ |
4b5f8d9a VB |
2980 | slab->memcg_data = memcg_data; |
2981 | } else if (cmpxchg(&slab->memcg_data, 0, memcg_data)) { | |
2e9bd483 | 2982 | /* |
4b5f8d9a VB |
2983 | * If the slab is already in use, somebody can allocate and |
2984 | * assign obj_cgroups in parallel. In this case the existing | |
2e9bd483 RG |
2985 | * objcg vector should be reused. |
2986 | */ | |
10befea9 | 2987 | kfree(vec); |
2e9bd483 RG |
2988 | return 0; |
2989 | } | |
10befea9 | 2990 | |
2e9bd483 | 2991 | kmemleak_not_leak(vec); |
10befea9 RG |
2992 | return 0; |
2993 | } | |
2994 | ||
fc4db90f RG |
2995 | static __always_inline |
2996 | struct mem_cgroup *mem_cgroup_from_obj_folio(struct folio *folio, void *p) | |
8380ce47 | 2997 | { |
8380ce47 | 2998 | /* |
9855609b RG |
2999 | * Slab objects are accounted individually, not per-page. |
3000 | * Memcg membership data for each individual object is saved in | |
4b5f8d9a | 3001 | * slab->memcg_data. |
8380ce47 | 3002 | */ |
4b5f8d9a VB |
3003 | if (folio_test_slab(folio)) { |
3004 | struct obj_cgroup **objcgs; | |
3005 | struct slab *slab; | |
9855609b RG |
3006 | unsigned int off; |
3007 | ||
4b5f8d9a VB |
3008 | slab = folio_slab(folio); |
3009 | objcgs = slab_objcgs(slab); | |
3010 | if (!objcgs) | |
3011 | return NULL; | |
3012 | ||
3013 | off = obj_to_index(slab->slab_cache, slab, p); | |
3014 | if (objcgs[off]) | |
3015 | return obj_cgroup_memcg(objcgs[off]); | |
10befea9 RG |
3016 | |
3017 | return NULL; | |
9855609b | 3018 | } |
8380ce47 | 3019 | |
bcfe06bf | 3020 | /* |
becacb04 | 3021 | * folio_memcg_check() is used here, because in theory we can encounter |
4b5f8d9a VB |
3022 | * a folio where the slab flag has been cleared already, but |
3023 | * slab->memcg_data has not been freed yet | |
becacb04 | 3024 | * folio_memcg_check() will guarantee that a proper memory |
bcfe06bf RG |
3025 | * cgroup pointer or NULL will be returned. |
3026 | */ | |
becacb04 | 3027 | return folio_memcg_check(folio); |
8380ce47 RG |
3028 | } |
3029 | ||
fc4db90f RG |
3030 | /* |
3031 | * Returns a pointer to the memory cgroup to which the kernel object is charged. | |
3032 | * | |
3033 | * A passed kernel object can be a slab object, vmalloc object or a generic | |
3034 | * kernel page, so different mechanisms for getting the memory cgroup pointer | |
3035 | * should be used. | |
3036 | * | |
3037 | * In certain cases (e.g. kernel stacks or large kmallocs with SLUB) the caller | |
3038 | * can not know for sure how the kernel object is implemented. | |
3039 | * mem_cgroup_from_obj() can be safely used in such cases. | |
3040 | * | |
3041 | * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(), | |
3042 | * cgroup_mutex, etc. | |
3043 | */ | |
3044 | struct mem_cgroup *mem_cgroup_from_obj(void *p) | |
3045 | { | |
3046 | struct folio *folio; | |
3047 | ||
3048 | if (mem_cgroup_disabled()) | |
3049 | return NULL; | |
3050 | ||
3051 | if (unlikely(is_vmalloc_addr(p))) | |
3052 | folio = page_folio(vmalloc_to_page(p)); | |
3053 | else | |
3054 | folio = virt_to_folio(p); | |
3055 | ||
3056 | return mem_cgroup_from_obj_folio(folio, p); | |
3057 | } | |
3058 | ||
3059 | /* | |
3060 | * Returns a pointer to the memory cgroup to which the kernel object is charged. | |
3061 | * Similar to mem_cgroup_from_obj(), but faster and not suitable for objects, | |
3062 | * allocated using vmalloc(). | |
3063 | * | |
3064 | * A passed kernel object must be a slab object or a generic kernel page. | |
3065 | * | |
3066 | * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(), | |
3067 | * cgroup_mutex, etc. | |
3068 | */ | |
3069 | struct mem_cgroup *mem_cgroup_from_slab_obj(void *p) | |
3070 | { | |
3071 | if (mem_cgroup_disabled()) | |
3072 | return NULL; | |
3073 | ||
3074 | return mem_cgroup_from_obj_folio(virt_to_folio(p), p); | |
3075 | } | |
3076 | ||
f4840ccf JW |
3077 | static struct obj_cgroup *__get_obj_cgroup_from_memcg(struct mem_cgroup *memcg) |
3078 | { | |
3079 | struct obj_cgroup *objcg = NULL; | |
3080 | ||
7848ed62 | 3081 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) { |
f4840ccf | 3082 | objcg = rcu_dereference(memcg->objcg); |
7d0715d0 | 3083 | if (likely(objcg && obj_cgroup_tryget(objcg))) |
f4840ccf JW |
3084 | break; |
3085 | objcg = NULL; | |
3086 | } | |
3087 | return objcg; | |
3088 | } | |
3089 | ||
1aacbd35 RG |
3090 | static struct obj_cgroup *current_objcg_update(void) |
3091 | { | |
3092 | struct mem_cgroup *memcg; | |
3093 | struct obj_cgroup *old, *objcg = NULL; | |
3094 | ||
3095 | do { | |
3096 | /* Atomically drop the update bit. */ | |
3097 | old = xchg(¤t->objcg, NULL); | |
3098 | if (old) { | |
3099 | old = (struct obj_cgroup *) | |
3100 | ((unsigned long)old & ~CURRENT_OBJCG_UPDATE_FLAG); | |
3101 | if (old) | |
3102 | obj_cgroup_put(old); | |
3103 | ||
3104 | old = NULL; | |
3105 | } | |
3106 | ||
3107 | /* If new objcg is NULL, no reason for the second atomic update. */ | |
3108 | if (!current->mm || (current->flags & PF_KTHREAD)) | |
3109 | return NULL; | |
3110 | ||
3111 | /* | |
3112 | * Release the objcg pointer from the previous iteration, | |
3113 | * if try_cmpxcg() below fails. | |
3114 | */ | |
3115 | if (unlikely(objcg)) { | |
3116 | obj_cgroup_put(objcg); | |
3117 | objcg = NULL; | |
3118 | } | |
3119 | ||
3120 | /* | |
3121 | * Obtain the new objcg pointer. The current task can be | |
3122 | * asynchronously moved to another memcg and the previous | |
3123 | * memcg can be offlined. So let's get the memcg pointer | |
3124 | * and try get a reference to objcg under a rcu read lock. | |
3125 | */ | |
3126 | ||
3127 | rcu_read_lock(); | |
3128 | memcg = mem_cgroup_from_task(current); | |
3129 | objcg = __get_obj_cgroup_from_memcg(memcg); | |
3130 | rcu_read_unlock(); | |
3131 | ||
3132 | /* | |
3133 | * Try set up a new objcg pointer atomically. If it | |
3134 | * fails, it means the update flag was set concurrently, so | |
3135 | * the whole procedure should be repeated. | |
3136 | */ | |
3137 | } while (!try_cmpxchg(¤t->objcg, &old, objcg)); | |
3138 | ||
3139 | return objcg; | |
3140 | } | |
3141 | ||
e86828e5 RG |
3142 | __always_inline struct obj_cgroup *current_obj_cgroup(void) |
3143 | { | |
3144 | struct mem_cgroup *memcg; | |
3145 | struct obj_cgroup *objcg; | |
3146 | ||
3147 | if (in_task()) { | |
3148 | memcg = current->active_memcg; | |
3149 | if (unlikely(memcg)) | |
3150 | goto from_memcg; | |
3151 | ||
3152 | objcg = READ_ONCE(current->objcg); | |
3153 | if (unlikely((unsigned long)objcg & CURRENT_OBJCG_UPDATE_FLAG)) | |
3154 | objcg = current_objcg_update(); | |
3155 | /* | |
3156 | * Objcg reference is kept by the task, so it's safe | |
3157 | * to use the objcg by the current task. | |
3158 | */ | |
3159 | return objcg; | |
3160 | } | |
3161 | ||
3162 | memcg = this_cpu_read(int_active_memcg); | |
3163 | if (unlikely(memcg)) | |
3164 | goto from_memcg; | |
3165 | ||
3166 | return NULL; | |
3167 | ||
3168 | from_memcg: | |
5f79489a | 3169 | objcg = NULL; |
e86828e5 RG |
3170 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) { |
3171 | /* | |
3172 | * Memcg pointer is protected by scope (see set_active_memcg()) | |
3173 | * and is pinning the corresponding objcg, so objcg can't go | |
3174 | * away and can be used within the scope without any additional | |
3175 | * protection. | |
3176 | */ | |
3177 | objcg = rcu_dereference_check(memcg->objcg, 1); | |
3178 | if (likely(objcg)) | |
3179 | break; | |
e86828e5 RG |
3180 | } |
3181 | ||
3182 | return objcg; | |
3183 | } | |
3184 | ||
074e3e26 | 3185 | struct obj_cgroup *get_obj_cgroup_from_folio(struct folio *folio) |
f4840ccf JW |
3186 | { |
3187 | struct obj_cgroup *objcg; | |
3188 | ||
f7a449f7 | 3189 | if (!memcg_kmem_online()) |
f4840ccf JW |
3190 | return NULL; |
3191 | ||
074e3e26 MWO |
3192 | if (folio_memcg_kmem(folio)) { |
3193 | objcg = __folio_objcg(folio); | |
f4840ccf JW |
3194 | obj_cgroup_get(objcg); |
3195 | } else { | |
3196 | struct mem_cgroup *memcg; | |
bf4f0599 | 3197 | |
f4840ccf | 3198 | rcu_read_lock(); |
074e3e26 | 3199 | memcg = __folio_memcg(folio); |
f4840ccf JW |
3200 | if (memcg) |
3201 | objcg = __get_obj_cgroup_from_memcg(memcg); | |
3202 | else | |
3203 | objcg = NULL; | |
3204 | rcu_read_unlock(); | |
3205 | } | |
bf4f0599 RG |
3206 | return objcg; |
3207 | } | |
3208 | ||
a8c49af3 YA |
3209 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) |
3210 | { | |
3211 | mod_memcg_state(memcg, MEMCG_KMEM, nr_pages); | |
3212 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { | |
3213 | if (nr_pages > 0) | |
3214 | page_counter_charge(&memcg->kmem, nr_pages); | |
3215 | else | |
3216 | page_counter_uncharge(&memcg->kmem, -nr_pages); | |
3217 | } | |
3218 | } | |
3219 | ||
3220 | ||
f1286fae MS |
3221 | /* |
3222 | * obj_cgroup_uncharge_pages: uncharge a number of kernel pages from a objcg | |
3223 | * @objcg: object cgroup to uncharge | |
3224 | * @nr_pages: number of pages to uncharge | |
3225 | */ | |
e74d2259 MS |
3226 | static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, |
3227 | unsigned int nr_pages) | |
3228 | { | |
3229 | struct mem_cgroup *memcg; | |
3230 | ||
3231 | memcg = get_mem_cgroup_from_objcg(objcg); | |
e74d2259 | 3232 | |
a8c49af3 | 3233 | memcg_account_kmem(memcg, -nr_pages); |
f1286fae | 3234 | refill_stock(memcg, nr_pages); |
e74d2259 | 3235 | |
e74d2259 | 3236 | css_put(&memcg->css); |
e74d2259 MS |
3237 | } |
3238 | ||
f1286fae MS |
3239 | /* |
3240 | * obj_cgroup_charge_pages: charge a number of kernel pages to a objcg | |
3241 | * @objcg: object cgroup to charge | |
45264778 | 3242 | * @gfp: reclaim mode |
92d0510c | 3243 | * @nr_pages: number of pages to charge |
45264778 VD |
3244 | * |
3245 | * Returns 0 on success, an error code on failure. | |
3246 | */ | |
f1286fae MS |
3247 | static int obj_cgroup_charge_pages(struct obj_cgroup *objcg, gfp_t gfp, |
3248 | unsigned int nr_pages) | |
7ae1e1d0 | 3249 | { |
f1286fae | 3250 | struct mem_cgroup *memcg; |
7ae1e1d0 GC |
3251 | int ret; |
3252 | ||
f1286fae MS |
3253 | memcg = get_mem_cgroup_from_objcg(objcg); |
3254 | ||
c5c8b16b | 3255 | ret = try_charge_memcg(memcg, gfp, nr_pages); |
52c29b04 | 3256 | if (ret) |
f1286fae | 3257 | goto out; |
52c29b04 | 3258 | |
a8c49af3 | 3259 | memcg_account_kmem(memcg, nr_pages); |
f1286fae MS |
3260 | out: |
3261 | css_put(&memcg->css); | |
4b13f64d | 3262 | |
f1286fae | 3263 | return ret; |
4b13f64d RG |
3264 | } |
3265 | ||
45264778 | 3266 | /** |
f4b00eab | 3267 | * __memcg_kmem_charge_page: charge a kmem page to the current memory cgroup |
45264778 VD |
3268 | * @page: page to charge |
3269 | * @gfp: reclaim mode | |
3270 | * @order: allocation order | |
3271 | * | |
3272 | * Returns 0 on success, an error code on failure. | |
3273 | */ | |
f4b00eab | 3274 | int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) |
7ae1e1d0 | 3275 | { |
b4e0b68f | 3276 | struct obj_cgroup *objcg; |
fcff7d7e | 3277 | int ret = 0; |
7ae1e1d0 | 3278 | |
e86828e5 | 3279 | objcg = current_obj_cgroup(); |
b4e0b68f MS |
3280 | if (objcg) { |
3281 | ret = obj_cgroup_charge_pages(objcg, gfp, 1 << order); | |
4d96ba35 | 3282 | if (!ret) { |
e86828e5 | 3283 | obj_cgroup_get(objcg); |
b4e0b68f | 3284 | page->memcg_data = (unsigned long)objcg | |
18b2db3b | 3285 | MEMCG_DATA_KMEM; |
1a3e1f40 | 3286 | return 0; |
4d96ba35 | 3287 | } |
c4159a75 | 3288 | } |
d05e83a6 | 3289 | return ret; |
7ae1e1d0 | 3290 | } |
49a18eae | 3291 | |
45264778 | 3292 | /** |
f4b00eab | 3293 | * __memcg_kmem_uncharge_page: uncharge a kmem page |
45264778 VD |
3294 | * @page: page to uncharge |
3295 | * @order: allocation order | |
3296 | */ | |
f4b00eab | 3297 | void __memcg_kmem_uncharge_page(struct page *page, int order) |
7ae1e1d0 | 3298 | { |
1b7e4464 | 3299 | struct folio *folio = page_folio(page); |
b4e0b68f | 3300 | struct obj_cgroup *objcg; |
f3ccb2c4 | 3301 | unsigned int nr_pages = 1 << order; |
7ae1e1d0 | 3302 | |
1b7e4464 | 3303 | if (!folio_memcg_kmem(folio)) |
7ae1e1d0 GC |
3304 | return; |
3305 | ||
1b7e4464 | 3306 | objcg = __folio_objcg(folio); |
b4e0b68f | 3307 | obj_cgroup_uncharge_pages(objcg, nr_pages); |
1b7e4464 | 3308 | folio->memcg_data = 0; |
b4e0b68f | 3309 | obj_cgroup_put(objcg); |
60d3fd32 | 3310 | } |
bf4f0599 | 3311 | |
68ac5b3c WL |
3312 | void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, |
3313 | enum node_stat_item idx, int nr) | |
3314 | { | |
fead2b86 | 3315 | struct memcg_stock_pcp *stock; |
56751146 | 3316 | struct obj_cgroup *old = NULL; |
68ac5b3c WL |
3317 | unsigned long flags; |
3318 | int *bytes; | |
3319 | ||
56751146 | 3320 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3321 | stock = this_cpu_ptr(&memcg_stock); |
3322 | ||
68ac5b3c WL |
3323 | /* |
3324 | * Save vmstat data in stock and skip vmstat array update unless | |
3325 | * accumulating over a page of vmstat data or when pgdat or idx | |
3326 | * changes. | |
3327 | */ | |
3b8abb32 | 3328 | if (READ_ONCE(stock->cached_objcg) != objcg) { |
56751146 | 3329 | old = drain_obj_stock(stock); |
68ac5b3c WL |
3330 | obj_cgroup_get(objcg); |
3331 | stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) | |
3332 | ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; | |
3b8abb32 | 3333 | WRITE_ONCE(stock->cached_objcg, objcg); |
68ac5b3c WL |
3334 | stock->cached_pgdat = pgdat; |
3335 | } else if (stock->cached_pgdat != pgdat) { | |
3336 | /* Flush the existing cached vmstat data */ | |
7fa0dacb WL |
3337 | struct pglist_data *oldpg = stock->cached_pgdat; |
3338 | ||
68ac5b3c | 3339 | if (stock->nr_slab_reclaimable_b) { |
7fa0dacb | 3340 | mod_objcg_mlstate(objcg, oldpg, NR_SLAB_RECLAIMABLE_B, |
68ac5b3c WL |
3341 | stock->nr_slab_reclaimable_b); |
3342 | stock->nr_slab_reclaimable_b = 0; | |
3343 | } | |
3344 | if (stock->nr_slab_unreclaimable_b) { | |
7fa0dacb | 3345 | mod_objcg_mlstate(objcg, oldpg, NR_SLAB_UNRECLAIMABLE_B, |
68ac5b3c WL |
3346 | stock->nr_slab_unreclaimable_b); |
3347 | stock->nr_slab_unreclaimable_b = 0; | |
3348 | } | |
3349 | stock->cached_pgdat = pgdat; | |
3350 | } | |
3351 | ||
3352 | bytes = (idx == NR_SLAB_RECLAIMABLE_B) ? &stock->nr_slab_reclaimable_b | |
3353 | : &stock->nr_slab_unreclaimable_b; | |
3354 | /* | |
3355 | * Even for large object >= PAGE_SIZE, the vmstat data will still be | |
3356 | * cached locally at least once before pushing it out. | |
3357 | */ | |
3358 | if (!*bytes) { | |
3359 | *bytes = nr; | |
3360 | nr = 0; | |
3361 | } else { | |
3362 | *bytes += nr; | |
3363 | if (abs(*bytes) > PAGE_SIZE) { | |
3364 | nr = *bytes; | |
3365 | *bytes = 0; | |
3366 | } else { | |
3367 | nr = 0; | |
3368 | } | |
3369 | } | |
3370 | if (nr) | |
3371 | mod_objcg_mlstate(objcg, pgdat, idx, nr); | |
3372 | ||
56751146 SAS |
3373 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
3374 | if (old) | |
3375 | obj_cgroup_put(old); | |
68ac5b3c WL |
3376 | } |
3377 | ||
bf4f0599 RG |
3378 | static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes) |
3379 | { | |
fead2b86 | 3380 | struct memcg_stock_pcp *stock; |
bf4f0599 RG |
3381 | unsigned long flags; |
3382 | bool ret = false; | |
3383 | ||
56751146 | 3384 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3385 | |
3386 | stock = this_cpu_ptr(&memcg_stock); | |
3b8abb32 | 3387 | if (objcg == READ_ONCE(stock->cached_objcg) && stock->nr_bytes >= nr_bytes) { |
bf4f0599 RG |
3388 | stock->nr_bytes -= nr_bytes; |
3389 | ret = true; | |
3390 | } | |
3391 | ||
56751146 | 3392 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
bf4f0599 RG |
3393 | |
3394 | return ret; | |
3395 | } | |
3396 | ||
56751146 | 3397 | static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) |
bf4f0599 | 3398 | { |
3b8abb32 | 3399 | struct obj_cgroup *old = READ_ONCE(stock->cached_objcg); |
bf4f0599 RG |
3400 | |
3401 | if (!old) | |
56751146 | 3402 | return NULL; |
bf4f0599 RG |
3403 | |
3404 | if (stock->nr_bytes) { | |
3405 | unsigned int nr_pages = stock->nr_bytes >> PAGE_SHIFT; | |
3406 | unsigned int nr_bytes = stock->nr_bytes & (PAGE_SIZE - 1); | |
3407 | ||
af9a3b69 JW |
3408 | if (nr_pages) { |
3409 | struct mem_cgroup *memcg; | |
3410 | ||
3411 | memcg = get_mem_cgroup_from_objcg(old); | |
3412 | ||
3413 | memcg_account_kmem(memcg, -nr_pages); | |
3414 | __refill_stock(memcg, nr_pages); | |
3415 | ||
3416 | css_put(&memcg->css); | |
3417 | } | |
bf4f0599 RG |
3418 | |
3419 | /* | |
3420 | * The leftover is flushed to the centralized per-memcg value. | |
3421 | * On the next attempt to refill obj stock it will be moved | |
3422 | * to a per-cpu stock (probably, on an other CPU), see | |
3423 | * refill_obj_stock(). | |
3424 | * | |
3425 | * How often it's flushed is a trade-off between the memory | |
3426 | * limit enforcement accuracy and potential CPU contention, | |
3427 | * so it might be changed in the future. | |
3428 | */ | |
3429 | atomic_add(nr_bytes, &old->nr_charged_bytes); | |
3430 | stock->nr_bytes = 0; | |
3431 | } | |
3432 | ||
68ac5b3c WL |
3433 | /* |
3434 | * Flush the vmstat data in current stock | |
3435 | */ | |
3436 | if (stock->nr_slab_reclaimable_b || stock->nr_slab_unreclaimable_b) { | |
3437 | if (stock->nr_slab_reclaimable_b) { | |
3438 | mod_objcg_mlstate(old, stock->cached_pgdat, | |
3439 | NR_SLAB_RECLAIMABLE_B, | |
3440 | stock->nr_slab_reclaimable_b); | |
3441 | stock->nr_slab_reclaimable_b = 0; | |
3442 | } | |
3443 | if (stock->nr_slab_unreclaimable_b) { | |
3444 | mod_objcg_mlstate(old, stock->cached_pgdat, | |
3445 | NR_SLAB_UNRECLAIMABLE_B, | |
3446 | stock->nr_slab_unreclaimable_b); | |
3447 | stock->nr_slab_unreclaimable_b = 0; | |
3448 | } | |
3449 | stock->cached_pgdat = NULL; | |
3450 | } | |
3451 | ||
3b8abb32 | 3452 | WRITE_ONCE(stock->cached_objcg, NULL); |
56751146 SAS |
3453 | /* |
3454 | * The `old' objects needs to be released by the caller via | |
3455 | * obj_cgroup_put() outside of memcg_stock_pcp::stock_lock. | |
3456 | */ | |
3457 | return old; | |
bf4f0599 RG |
3458 | } |
3459 | ||
3460 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, | |
3461 | struct mem_cgroup *root_memcg) | |
3462 | { | |
3b8abb32 | 3463 | struct obj_cgroup *objcg = READ_ONCE(stock->cached_objcg); |
bf4f0599 RG |
3464 | struct mem_cgroup *memcg; |
3465 | ||
3b8abb32 RG |
3466 | if (objcg) { |
3467 | memcg = obj_cgroup_memcg(objcg); | |
bf4f0599 RG |
3468 | if (memcg && mem_cgroup_is_descendant(memcg, root_memcg)) |
3469 | return true; | |
3470 | } | |
3471 | ||
3472 | return false; | |
3473 | } | |
3474 | ||
5387c904 WL |
3475 | static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes, |
3476 | bool allow_uncharge) | |
bf4f0599 | 3477 | { |
fead2b86 | 3478 | struct memcg_stock_pcp *stock; |
56751146 | 3479 | struct obj_cgroup *old = NULL; |
bf4f0599 | 3480 | unsigned long flags; |
5387c904 | 3481 | unsigned int nr_pages = 0; |
bf4f0599 | 3482 | |
56751146 | 3483 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3484 | |
3485 | stock = this_cpu_ptr(&memcg_stock); | |
3b8abb32 | 3486 | if (READ_ONCE(stock->cached_objcg) != objcg) { /* reset if necessary */ |
56751146 | 3487 | old = drain_obj_stock(stock); |
bf4f0599 | 3488 | obj_cgroup_get(objcg); |
3b8abb32 | 3489 | WRITE_ONCE(stock->cached_objcg, objcg); |
5387c904 WL |
3490 | stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) |
3491 | ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; | |
3492 | allow_uncharge = true; /* Allow uncharge when objcg changes */ | |
bf4f0599 RG |
3493 | } |
3494 | stock->nr_bytes += nr_bytes; | |
3495 | ||
5387c904 WL |
3496 | if (allow_uncharge && (stock->nr_bytes > PAGE_SIZE)) { |
3497 | nr_pages = stock->nr_bytes >> PAGE_SHIFT; | |
3498 | stock->nr_bytes &= (PAGE_SIZE - 1); | |
3499 | } | |
bf4f0599 | 3500 | |
56751146 SAS |
3501 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
3502 | if (old) | |
3503 | obj_cgroup_put(old); | |
5387c904 WL |
3504 | |
3505 | if (nr_pages) | |
3506 | obj_cgroup_uncharge_pages(objcg, nr_pages); | |
bf4f0599 RG |
3507 | } |
3508 | ||
3509 | int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size) | |
3510 | { | |
bf4f0599 RG |
3511 | unsigned int nr_pages, nr_bytes; |
3512 | int ret; | |
3513 | ||
3514 | if (consume_obj_stock(objcg, size)) | |
3515 | return 0; | |
3516 | ||
3517 | /* | |
5387c904 | 3518 | * In theory, objcg->nr_charged_bytes can have enough |
bf4f0599 | 3519 | * pre-charged bytes to satisfy the allocation. However, |
5387c904 WL |
3520 | * flushing objcg->nr_charged_bytes requires two atomic |
3521 | * operations, and objcg->nr_charged_bytes can't be big. | |
3522 | * The shared objcg->nr_charged_bytes can also become a | |
3523 | * performance bottleneck if all tasks of the same memcg are | |
3524 | * trying to update it. So it's better to ignore it and try | |
3525 | * grab some new pages. The stock's nr_bytes will be flushed to | |
3526 | * objcg->nr_charged_bytes later on when objcg changes. | |
3527 | * | |
3528 | * The stock's nr_bytes may contain enough pre-charged bytes | |
3529 | * to allow one less page from being charged, but we can't rely | |
3530 | * on the pre-charged bytes not being changed outside of | |
3531 | * consume_obj_stock() or refill_obj_stock(). So ignore those | |
3532 | * pre-charged bytes as well when charging pages. To avoid a | |
3533 | * page uncharge right after a page charge, we set the | |
3534 | * allow_uncharge flag to false when calling refill_obj_stock() | |
3535 | * to temporarily allow the pre-charged bytes to exceed the page | |
3536 | * size limit. The maximum reachable value of the pre-charged | |
3537 | * bytes is (sizeof(object) + PAGE_SIZE - 2) if there is no data | |
3538 | * race. | |
bf4f0599 | 3539 | */ |
bf4f0599 RG |
3540 | nr_pages = size >> PAGE_SHIFT; |
3541 | nr_bytes = size & (PAGE_SIZE - 1); | |
3542 | ||
3543 | if (nr_bytes) | |
3544 | nr_pages += 1; | |
3545 | ||
e74d2259 | 3546 | ret = obj_cgroup_charge_pages(objcg, gfp, nr_pages); |
bf4f0599 | 3547 | if (!ret && nr_bytes) |
5387c904 | 3548 | refill_obj_stock(objcg, PAGE_SIZE - nr_bytes, false); |
bf4f0599 | 3549 | |
bf4f0599 RG |
3550 | return ret; |
3551 | } | |
3552 | ||
3553 | void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size) | |
3554 | { | |
5387c904 | 3555 | refill_obj_stock(objcg, size, true); |
bf4f0599 RG |
3556 | } |
3557 | ||
84c07d11 | 3558 | #endif /* CONFIG_MEMCG_KMEM */ |
7ae1e1d0 | 3559 | |
ca3e0214 | 3560 | /* |
be6c8982 | 3561 | * Because page_memcg(head) is not set on tails, set it now. |
ca3e0214 | 3562 | */ |
be6c8982 | 3563 | void split_page_memcg(struct page *head, unsigned int nr) |
ca3e0214 | 3564 | { |
1b7e4464 MWO |
3565 | struct folio *folio = page_folio(head); |
3566 | struct mem_cgroup *memcg = folio_memcg(folio); | |
e94c8a9c | 3567 | int i; |
ca3e0214 | 3568 | |
be6c8982 | 3569 | if (mem_cgroup_disabled() || !memcg) |
3d37c4a9 | 3570 | return; |
b070e65c | 3571 | |
be6c8982 | 3572 | for (i = 1; i < nr; i++) |
1b7e4464 | 3573 | folio_page(folio, i)->memcg_data = folio->memcg_data; |
b4e0b68f | 3574 | |
1b7e4464 MWO |
3575 | if (folio_memcg_kmem(folio)) |
3576 | obj_cgroup_get_many(__folio_objcg(folio), nr - 1); | |
b4e0b68f MS |
3577 | else |
3578 | css_get_many(&memcg->css, nr - 1); | |
ca3e0214 | 3579 | } |
ca3e0214 | 3580 | |
e55b9f96 | 3581 | #ifdef CONFIG_SWAP |
02491447 DN |
3582 | /** |
3583 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
3584 | * @entry: swap entry to be moved | |
3585 | * @from: mem_cgroup which the entry is moved from | |
3586 | * @to: mem_cgroup which the entry is moved to | |
3587 | * | |
3588 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
3589 | * as the mem_cgroup's id of @from. | |
3590 | * | |
3591 | * Returns 0 on success, -EINVAL on failure. | |
3592 | * | |
3e32cb2e | 3593 | * The caller must have charged to @to, IOW, called page_counter_charge() about |
02491447 DN |
3594 | * both res and memsw, and called css_get(). |
3595 | */ | |
3596 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 3597 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
3598 | { |
3599 | unsigned short old_id, new_id; | |
3600 | ||
34c00c31 LZ |
3601 | old_id = mem_cgroup_id(from); |
3602 | new_id = mem_cgroup_id(to); | |
02491447 DN |
3603 | |
3604 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
c9019e9b JW |
3605 | mod_memcg_state(from, MEMCG_SWAP, -1); |
3606 | mod_memcg_state(to, MEMCG_SWAP, 1); | |
02491447 DN |
3607 | return 0; |
3608 | } | |
3609 | return -EINVAL; | |
3610 | } | |
3611 | #else | |
3612 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 3613 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
3614 | { |
3615 | return -EINVAL; | |
3616 | } | |
8c7c6e34 | 3617 | #endif |
d13d1443 | 3618 | |
bbec2e15 | 3619 | static DEFINE_MUTEX(memcg_max_mutex); |
f212ad7c | 3620 | |
bbec2e15 RG |
3621 | static int mem_cgroup_resize_max(struct mem_cgroup *memcg, |
3622 | unsigned long max, bool memsw) | |
628f4235 | 3623 | { |
3e32cb2e | 3624 | bool enlarge = false; |
bb4a7ea2 | 3625 | bool drained = false; |
3e32cb2e | 3626 | int ret; |
c054a78c YZ |
3627 | bool limits_invariant; |
3628 | struct page_counter *counter = memsw ? &memcg->memsw : &memcg->memory; | |
81d39c20 | 3629 | |
3e32cb2e | 3630 | do { |
628f4235 KH |
3631 | if (signal_pending(current)) { |
3632 | ret = -EINTR; | |
3633 | break; | |
3634 | } | |
3e32cb2e | 3635 | |
bbec2e15 | 3636 | mutex_lock(&memcg_max_mutex); |
c054a78c YZ |
3637 | /* |
3638 | * Make sure that the new limit (memsw or memory limit) doesn't | |
bbec2e15 | 3639 | * break our basic invariant rule memory.max <= memsw.max. |
c054a78c | 3640 | */ |
15b42562 | 3641 | limits_invariant = memsw ? max >= READ_ONCE(memcg->memory.max) : |
bbec2e15 | 3642 | max <= memcg->memsw.max; |
c054a78c | 3643 | if (!limits_invariant) { |
bbec2e15 | 3644 | mutex_unlock(&memcg_max_mutex); |
8c7c6e34 | 3645 | ret = -EINVAL; |
8c7c6e34 KH |
3646 | break; |
3647 | } | |
bbec2e15 | 3648 | if (max > counter->max) |
3e32cb2e | 3649 | enlarge = true; |
bbec2e15 RG |
3650 | ret = page_counter_set_max(counter, max); |
3651 | mutex_unlock(&memcg_max_mutex); | |
8c7c6e34 KH |
3652 | |
3653 | if (!ret) | |
3654 | break; | |
3655 | ||
bb4a7ea2 SB |
3656 | if (!drained) { |
3657 | drain_all_stock(memcg); | |
3658 | drained = true; | |
3659 | continue; | |
3660 | } | |
3661 | ||
73b73bac | 3662 | if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, |
55ab834a | 3663 | memsw ? 0 : MEMCG_RECLAIM_MAY_SWAP)) { |
1ab5c056 AR |
3664 | ret = -EBUSY; |
3665 | break; | |
3666 | } | |
3667 | } while (true); | |
3e32cb2e | 3668 | |
3c11ecf4 KH |
3669 | if (!ret && enlarge) |
3670 | memcg_oom_recover(memcg); | |
3e32cb2e | 3671 | |
628f4235 KH |
3672 | return ret; |
3673 | } | |
3674 | ||
ef8f2327 | 3675 | unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, |
0608f43d AM |
3676 | gfp_t gfp_mask, |
3677 | unsigned long *total_scanned) | |
3678 | { | |
3679 | unsigned long nr_reclaimed = 0; | |
ef8f2327 | 3680 | struct mem_cgroup_per_node *mz, *next_mz = NULL; |
0608f43d AM |
3681 | unsigned long reclaimed; |
3682 | int loop = 0; | |
ef8f2327 | 3683 | struct mem_cgroup_tree_per_node *mctz; |
3e32cb2e | 3684 | unsigned long excess; |
0608f43d | 3685 | |
e4dde56c YZ |
3686 | if (lru_gen_enabled()) |
3687 | return 0; | |
3688 | ||
0608f43d AM |
3689 | if (order > 0) |
3690 | return 0; | |
3691 | ||
2ab082ba | 3692 | mctz = soft_limit_tree.rb_tree_per_node[pgdat->node_id]; |
d6507ff5 MH |
3693 | |
3694 | /* | |
3695 | * Do not even bother to check the largest node if the root | |
3696 | * is empty. Do it lockless to prevent lock bouncing. Races | |
3697 | * are acceptable as soft limit is best effort anyway. | |
3698 | */ | |
bfc7228b | 3699 | if (!mctz || RB_EMPTY_ROOT(&mctz->rb_root)) |
d6507ff5 MH |
3700 | return 0; |
3701 | ||
0608f43d AM |
3702 | /* |
3703 | * This loop can run a while, specially if mem_cgroup's continuously | |
3704 | * keep exceeding their soft limit and putting the system under | |
3705 | * pressure | |
3706 | */ | |
3707 | do { | |
3708 | if (next_mz) | |
3709 | mz = next_mz; | |
3710 | else | |
3711 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
3712 | if (!mz) | |
3713 | break; | |
3714 | ||
ef8f2327 | 3715 | reclaimed = mem_cgroup_soft_reclaim(mz->memcg, pgdat, |
d8f65338 | 3716 | gfp_mask, total_scanned); |
0608f43d | 3717 | nr_reclaimed += reclaimed; |
0a31bc97 | 3718 | spin_lock_irq(&mctz->lock); |
0608f43d AM |
3719 | |
3720 | /* | |
3721 | * If we failed to reclaim anything from this memory cgroup | |
3722 | * it is time to move on to the next cgroup | |
3723 | */ | |
3724 | next_mz = NULL; | |
bc2f2e7f VD |
3725 | if (!reclaimed) |
3726 | next_mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
3727 | ||
3e32cb2e | 3728 | excess = soft_limit_excess(mz->memcg); |
0608f43d AM |
3729 | /* |
3730 | * One school of thought says that we should not add | |
3731 | * back the node to the tree if reclaim returns 0. | |
3732 | * But our reclaim could return 0, simply because due | |
3733 | * to priority we are exposing a smaller subset of | |
3734 | * memory to reclaim from. Consider this as a longer | |
3735 | * term TODO. | |
3736 | */ | |
3737 | /* If excess == 0, no tree ops */ | |
cf2c8127 | 3738 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 3739 | spin_unlock_irq(&mctz->lock); |
0608f43d AM |
3740 | css_put(&mz->memcg->css); |
3741 | loop++; | |
3742 | /* | |
3743 | * Could not reclaim anything and there are no more | |
3744 | * mem cgroups to try or we seem to be looping without | |
3745 | * reclaiming anything. | |
3746 | */ | |
3747 | if (!nr_reclaimed && | |
3748 | (next_mz == NULL || | |
3749 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
3750 | break; | |
3751 | } while (!nr_reclaimed); | |
3752 | if (next_mz) | |
3753 | css_put(&next_mz->memcg->css); | |
3754 | return nr_reclaimed; | |
3755 | } | |
3756 | ||
c26251f9 | 3757 | /* |
51038171 | 3758 | * Reclaims as many pages from the given memcg as possible. |
c26251f9 MH |
3759 | * |
3760 | * Caller is responsible for holding css reference for memcg. | |
3761 | */ | |
3762 | static int mem_cgroup_force_empty(struct mem_cgroup *memcg) | |
3763 | { | |
d977aa93 | 3764 | int nr_retries = MAX_RECLAIM_RETRIES; |
c26251f9 | 3765 | |
c1e862c1 KH |
3766 | /* we call try-to-free pages for make this cgroup empty */ |
3767 | lru_add_drain_all(); | |
d12c60f6 JS |
3768 | |
3769 | drain_all_stock(memcg); | |
3770 | ||
f817ed48 | 3771 | /* try to free all pages in this cgroup */ |
3e32cb2e | 3772 | while (nr_retries && page_counter_read(&memcg->memory)) { |
c26251f9 MH |
3773 | if (signal_pending(current)) |
3774 | return -EINTR; | |
3775 | ||
73b73bac | 3776 | if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, |
55ab834a | 3777 | MEMCG_RECLAIM_MAY_SWAP)) |
f817ed48 | 3778 | nr_retries--; |
f817ed48 | 3779 | } |
ab5196c2 MH |
3780 | |
3781 | return 0; | |
cc847582 KH |
3782 | } |
3783 | ||
6770c64e TH |
3784 | static ssize_t mem_cgroup_force_empty_write(struct kernfs_open_file *of, |
3785 | char *buf, size_t nbytes, | |
3786 | loff_t off) | |
c1e862c1 | 3787 | { |
6770c64e | 3788 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
c26251f9 | 3789 | |
d8423011 MH |
3790 | if (mem_cgroup_is_root(memcg)) |
3791 | return -EINVAL; | |
6770c64e | 3792 | return mem_cgroup_force_empty(memcg) ?: nbytes; |
c1e862c1 KH |
3793 | } |
3794 | ||
182446d0 TH |
3795 | static u64 mem_cgroup_hierarchy_read(struct cgroup_subsys_state *css, |
3796 | struct cftype *cft) | |
18f59ea7 | 3797 | { |
bef8620c | 3798 | return 1; |
18f59ea7 BS |
3799 | } |
3800 | ||
182446d0 TH |
3801 | static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css, |
3802 | struct cftype *cft, u64 val) | |
18f59ea7 | 3803 | { |
bef8620c | 3804 | if (val == 1) |
0b8f73e1 | 3805 | return 0; |
567fb435 | 3806 | |
bef8620c RG |
3807 | pr_warn_once("Non-hierarchical mode is deprecated. " |
3808 | "Please report your usecase to linux-mm@kvack.org if you " | |
3809 | "depend on this functionality.\n"); | |
567fb435 | 3810 | |
bef8620c | 3811 | return -EINVAL; |
18f59ea7 BS |
3812 | } |
3813 | ||
6f646156 | 3814 | static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) |
ce00a967 | 3815 | { |
42a30035 | 3816 | unsigned long val; |
ce00a967 | 3817 | |
3e32cb2e | 3818 | if (mem_cgroup_is_root(memcg)) { |
a2174e95 | 3819 | /* |
f82a7a86 YA |
3820 | * Approximate root's usage from global state. This isn't |
3821 | * perfect, but the root usage was always an approximation. | |
a2174e95 | 3822 | */ |
f82a7a86 YA |
3823 | val = global_node_page_state(NR_FILE_PAGES) + |
3824 | global_node_page_state(NR_ANON_MAPPED); | |
42a30035 | 3825 | if (swap) |
f82a7a86 | 3826 | val += total_swap_pages - get_nr_swap_pages(); |
3e32cb2e | 3827 | } else { |
ce00a967 | 3828 | if (!swap) |
3e32cb2e | 3829 | val = page_counter_read(&memcg->memory); |
ce00a967 | 3830 | else |
3e32cb2e | 3831 | val = page_counter_read(&memcg->memsw); |
ce00a967 | 3832 | } |
c12176d3 | 3833 | return val; |
ce00a967 JW |
3834 | } |
3835 | ||
3e32cb2e JW |
3836 | enum { |
3837 | RES_USAGE, | |
3838 | RES_LIMIT, | |
3839 | RES_MAX_USAGE, | |
3840 | RES_FAILCNT, | |
3841 | RES_SOFT_LIMIT, | |
3842 | }; | |
ce00a967 | 3843 | |
791badbd | 3844 | static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css, |
05b84301 | 3845 | struct cftype *cft) |
8cdea7c0 | 3846 | { |
182446d0 | 3847 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3e32cb2e | 3848 | struct page_counter *counter; |
af36f906 | 3849 | |
3e32cb2e | 3850 | switch (MEMFILE_TYPE(cft->private)) { |
8c7c6e34 | 3851 | case _MEM: |
3e32cb2e JW |
3852 | counter = &memcg->memory; |
3853 | break; | |
8c7c6e34 | 3854 | case _MEMSWAP: |
3e32cb2e JW |
3855 | counter = &memcg->memsw; |
3856 | break; | |
510fc4e1 | 3857 | case _KMEM: |
3e32cb2e | 3858 | counter = &memcg->kmem; |
510fc4e1 | 3859 | break; |
d55f90bf | 3860 | case _TCP: |
0db15298 | 3861 | counter = &memcg->tcpmem; |
d55f90bf | 3862 | break; |
8c7c6e34 KH |
3863 | default: |
3864 | BUG(); | |
8c7c6e34 | 3865 | } |
3e32cb2e JW |
3866 | |
3867 | switch (MEMFILE_ATTR(cft->private)) { | |
3868 | case RES_USAGE: | |
3869 | if (counter == &memcg->memory) | |
c12176d3 | 3870 | return (u64)mem_cgroup_usage(memcg, false) * PAGE_SIZE; |
3e32cb2e | 3871 | if (counter == &memcg->memsw) |
c12176d3 | 3872 | return (u64)mem_cgroup_usage(memcg, true) * PAGE_SIZE; |
3e32cb2e JW |
3873 | return (u64)page_counter_read(counter) * PAGE_SIZE; |
3874 | case RES_LIMIT: | |
bbec2e15 | 3875 | return (u64)counter->max * PAGE_SIZE; |
3e32cb2e JW |
3876 | case RES_MAX_USAGE: |
3877 | return (u64)counter->watermark * PAGE_SIZE; | |
3878 | case RES_FAILCNT: | |
3879 | return counter->failcnt; | |
3880 | case RES_SOFT_LIMIT: | |
2178e20c | 3881 | return (u64)READ_ONCE(memcg->soft_limit) * PAGE_SIZE; |
3e32cb2e JW |
3882 | default: |
3883 | BUG(); | |
3884 | } | |
8cdea7c0 | 3885 | } |
510fc4e1 | 3886 | |
6b0ba2ab FS |
3887 | /* |
3888 | * This function doesn't do anything useful. Its only job is to provide a read | |
3889 | * handler for a file so that cgroup_file_mode() will add read permissions. | |
3890 | */ | |
3891 | static int mem_cgroup_dummy_seq_show(__always_unused struct seq_file *m, | |
3892 | __always_unused void *v) | |
3893 | { | |
3894 | return -EINVAL; | |
3895 | } | |
3896 | ||
84c07d11 | 3897 | #ifdef CONFIG_MEMCG_KMEM |
567e9ab2 | 3898 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
d6441637 | 3899 | { |
bf4f0599 | 3900 | struct obj_cgroup *objcg; |
d6441637 | 3901 | |
9c94bef9 | 3902 | if (mem_cgroup_kmem_disabled()) |
b313aeee VD |
3903 | return 0; |
3904 | ||
da0efe30 MS |
3905 | if (unlikely(mem_cgroup_is_root(memcg))) |
3906 | return 0; | |
d6441637 | 3907 | |
bf4f0599 | 3908 | objcg = obj_cgroup_alloc(); |
f9c69d63 | 3909 | if (!objcg) |
bf4f0599 | 3910 | return -ENOMEM; |
f9c69d63 | 3911 | |
bf4f0599 RG |
3912 | objcg->memcg = memcg; |
3913 | rcu_assign_pointer(memcg->objcg, objcg); | |
675d6c9b RG |
3914 | obj_cgroup_get(objcg); |
3915 | memcg->orig_objcg = objcg; | |
bf4f0599 | 3916 | |
f7a449f7 | 3917 | static_branch_enable(&memcg_kmem_online_key); |
d648bcc7 | 3918 | |
f9c69d63 | 3919 | memcg->kmemcg_id = memcg->id.id; |
0b8f73e1 JW |
3920 | |
3921 | return 0; | |
d6441637 VD |
3922 | } |
3923 | ||
8e0a8912 JW |
3924 | static void memcg_offline_kmem(struct mem_cgroup *memcg) |
3925 | { | |
64268868 | 3926 | struct mem_cgroup *parent; |
8e0a8912 | 3927 | |
9c94bef9 | 3928 | if (mem_cgroup_kmem_disabled()) |
da0efe30 MS |
3929 | return; |
3930 | ||
3931 | if (unlikely(mem_cgroup_is_root(memcg))) | |
8e0a8912 | 3932 | return; |
9855609b | 3933 | |
8e0a8912 JW |
3934 | parent = parent_mem_cgroup(memcg); |
3935 | if (!parent) | |
3936 | parent = root_mem_cgroup; | |
3937 | ||
bf4f0599 | 3938 | memcg_reparent_objcgs(memcg, parent); |
fb2f2b0a | 3939 | |
8e0a8912 | 3940 | /* |
64268868 MS |
3941 | * After we have finished memcg_reparent_objcgs(), all list_lrus |
3942 | * corresponding to this cgroup are guaranteed to remain empty. | |
3943 | * The ordering is imposed by list_lru_node->lock taken by | |
1f391eb2 | 3944 | * memcg_reparent_list_lrus(). |
8e0a8912 | 3945 | */ |
1f391eb2 | 3946 | memcg_reparent_list_lrus(memcg, parent); |
8e0a8912 | 3947 | } |
d6441637 | 3948 | #else |
0b8f73e1 | 3949 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
127424c8 JW |
3950 | { |
3951 | return 0; | |
3952 | } | |
3953 | static void memcg_offline_kmem(struct mem_cgroup *memcg) | |
3954 | { | |
3955 | } | |
84c07d11 | 3956 | #endif /* CONFIG_MEMCG_KMEM */ |
127424c8 | 3957 | |
bbec2e15 | 3958 | static int memcg_update_tcp_max(struct mem_cgroup *memcg, unsigned long max) |
d55f90bf VD |
3959 | { |
3960 | int ret; | |
3961 | ||
bbec2e15 | 3962 | mutex_lock(&memcg_max_mutex); |
d55f90bf | 3963 | |
bbec2e15 | 3964 | ret = page_counter_set_max(&memcg->tcpmem, max); |
d55f90bf VD |
3965 | if (ret) |
3966 | goto out; | |
3967 | ||
0db15298 | 3968 | if (!memcg->tcpmem_active) { |
d55f90bf VD |
3969 | /* |
3970 | * The active flag needs to be written after the static_key | |
3971 | * update. This is what guarantees that the socket activation | |
2d758073 JW |
3972 | * function is the last one to run. See mem_cgroup_sk_alloc() |
3973 | * for details, and note that we don't mark any socket as | |
3974 | * belonging to this memcg until that flag is up. | |
d55f90bf VD |
3975 | * |
3976 | * We need to do this, because static_keys will span multiple | |
3977 | * sites, but we can't control their order. If we mark a socket | |
3978 | * as accounted, but the accounting functions are not patched in | |
3979 | * yet, we'll lose accounting. | |
3980 | * | |
2d758073 | 3981 | * We never race with the readers in mem_cgroup_sk_alloc(), |
d55f90bf VD |
3982 | * because when this value change, the code to process it is not |
3983 | * patched in yet. | |
3984 | */ | |
3985 | static_branch_inc(&memcg_sockets_enabled_key); | |
0db15298 | 3986 | memcg->tcpmem_active = true; |
d55f90bf VD |
3987 | } |
3988 | out: | |
bbec2e15 | 3989 | mutex_unlock(&memcg_max_mutex); |
d55f90bf VD |
3990 | return ret; |
3991 | } | |
d55f90bf | 3992 | |
628f4235 KH |
3993 | /* |
3994 | * The user of this function is... | |
3995 | * RES_LIMIT. | |
3996 | */ | |
451af504 TH |
3997 | static ssize_t mem_cgroup_write(struct kernfs_open_file *of, |
3998 | char *buf, size_t nbytes, loff_t off) | |
8cdea7c0 | 3999 | { |
451af504 | 4000 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 4001 | unsigned long nr_pages; |
628f4235 KH |
4002 | int ret; |
4003 | ||
451af504 | 4004 | buf = strstrip(buf); |
650c5e56 | 4005 | ret = page_counter_memparse(buf, "-1", &nr_pages); |
3e32cb2e JW |
4006 | if (ret) |
4007 | return ret; | |
af36f906 | 4008 | |
3e32cb2e | 4009 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
628f4235 | 4010 | case RES_LIMIT: |
4b3bde4c BS |
4011 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
4012 | ret = -EINVAL; | |
4013 | break; | |
4014 | } | |
3e32cb2e JW |
4015 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
4016 | case _MEM: | |
bbec2e15 | 4017 | ret = mem_cgroup_resize_max(memcg, nr_pages, false); |
8c7c6e34 | 4018 | break; |
3e32cb2e | 4019 | case _MEMSWAP: |
bbec2e15 | 4020 | ret = mem_cgroup_resize_max(memcg, nr_pages, true); |
296c81d8 | 4021 | break; |
4597648f MH |
4022 | case _KMEM: |
4023 | pr_warn_once("kmem.limit_in_bytes is deprecated and will be removed. " | |
4024 | "Writing any value to this file has no effect. " | |
4025 | "Please report your usecase to linux-mm@kvack.org if you " | |
4026 | "depend on this functionality.\n"); | |
4027 | ret = 0; | |
4028 | break; | |
d55f90bf | 4029 | case _TCP: |
bbec2e15 | 4030 | ret = memcg_update_tcp_max(memcg, nr_pages); |
d55f90bf | 4031 | break; |
3e32cb2e | 4032 | } |
296c81d8 | 4033 | break; |
3e32cb2e | 4034 | case RES_SOFT_LIMIT: |
2343e88d SAS |
4035 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) { |
4036 | ret = -EOPNOTSUPP; | |
4037 | } else { | |
2178e20c | 4038 | WRITE_ONCE(memcg->soft_limit, nr_pages); |
2343e88d SAS |
4039 | ret = 0; |
4040 | } | |
628f4235 KH |
4041 | break; |
4042 | } | |
451af504 | 4043 | return ret ?: nbytes; |
8cdea7c0 BS |
4044 | } |
4045 | ||
6770c64e TH |
4046 | static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf, |
4047 | size_t nbytes, loff_t off) | |
c84872e1 | 4048 | { |
6770c64e | 4049 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 4050 | struct page_counter *counter; |
c84872e1 | 4051 | |
3e32cb2e JW |
4052 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
4053 | case _MEM: | |
4054 | counter = &memcg->memory; | |
4055 | break; | |
4056 | case _MEMSWAP: | |
4057 | counter = &memcg->memsw; | |
4058 | break; | |
4059 | case _KMEM: | |
4060 | counter = &memcg->kmem; | |
4061 | break; | |
d55f90bf | 4062 | case _TCP: |
0db15298 | 4063 | counter = &memcg->tcpmem; |
d55f90bf | 4064 | break; |
3e32cb2e JW |
4065 | default: |
4066 | BUG(); | |
4067 | } | |
af36f906 | 4068 | |
3e32cb2e | 4069 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
29f2a4da | 4070 | case RES_MAX_USAGE: |
3e32cb2e | 4071 | page_counter_reset_watermark(counter); |
29f2a4da PE |
4072 | break; |
4073 | case RES_FAILCNT: | |
3e32cb2e | 4074 | counter->failcnt = 0; |
29f2a4da | 4075 | break; |
3e32cb2e JW |
4076 | default: |
4077 | BUG(); | |
29f2a4da | 4078 | } |
f64c3f54 | 4079 | |
6770c64e | 4080 | return nbytes; |
c84872e1 PE |
4081 | } |
4082 | ||
182446d0 | 4083 | static u64 mem_cgroup_move_charge_read(struct cgroup_subsys_state *css, |
7dc74be0 DN |
4084 | struct cftype *cft) |
4085 | { | |
182446d0 | 4086 | return mem_cgroup_from_css(css)->move_charge_at_immigrate; |
7dc74be0 DN |
4087 | } |
4088 | ||
02491447 | 4089 | #ifdef CONFIG_MMU |
182446d0 | 4090 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
7dc74be0 DN |
4091 | struct cftype *cft, u64 val) |
4092 | { | |
182446d0 | 4093 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
7dc74be0 | 4094 | |
da34a848 JW |
4095 | pr_warn_once("Cgroup memory moving (move_charge_at_immigrate) is deprecated. " |
4096 | "Please report your usecase to linux-mm@kvack.org if you " | |
4097 | "depend on this functionality.\n"); | |
4098 | ||
1dfab5ab | 4099 | if (val & ~MOVE_MASK) |
7dc74be0 | 4100 | return -EINVAL; |
ee5e8472 | 4101 | |
7dc74be0 | 4102 | /* |
ee5e8472 GC |
4103 | * No kind of locking is needed in here, because ->can_attach() will |
4104 | * check this value once in the beginning of the process, and then carry | |
4105 | * on with stale data. This means that changes to this value will only | |
4106 | * affect task migrations starting after the change. | |
7dc74be0 | 4107 | */ |
c0ff4b85 | 4108 | memcg->move_charge_at_immigrate = val; |
7dc74be0 DN |
4109 | return 0; |
4110 | } | |
02491447 | 4111 | #else |
182446d0 | 4112 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
02491447 DN |
4113 | struct cftype *cft, u64 val) |
4114 | { | |
4115 | return -ENOSYS; | |
4116 | } | |
4117 | #endif | |
7dc74be0 | 4118 | |
406eb0c9 | 4119 | #ifdef CONFIG_NUMA |
113b7dfd JW |
4120 | |
4121 | #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE)) | |
4122 | #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON)) | |
4123 | #define LRU_ALL ((1 << NR_LRU_LISTS) - 1) | |
4124 | ||
4125 | static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, | |
dd8657b6 | 4126 | int nid, unsigned int lru_mask, bool tree) |
113b7dfd | 4127 | { |
867e5e1d | 4128 | struct lruvec *lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); |
113b7dfd JW |
4129 | unsigned long nr = 0; |
4130 | enum lru_list lru; | |
4131 | ||
4132 | VM_BUG_ON((unsigned)nid >= nr_node_ids); | |
4133 | ||
4134 | for_each_lru(lru) { | |
4135 | if (!(BIT(lru) & lru_mask)) | |
4136 | continue; | |
dd8657b6 SB |
4137 | if (tree) |
4138 | nr += lruvec_page_state(lruvec, NR_LRU_BASE + lru); | |
4139 | else | |
4140 | nr += lruvec_page_state_local(lruvec, NR_LRU_BASE + lru); | |
113b7dfd JW |
4141 | } |
4142 | return nr; | |
4143 | } | |
4144 | ||
4145 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, | |
dd8657b6 SB |
4146 | unsigned int lru_mask, |
4147 | bool tree) | |
113b7dfd JW |
4148 | { |
4149 | unsigned long nr = 0; | |
4150 | enum lru_list lru; | |
4151 | ||
4152 | for_each_lru(lru) { | |
4153 | if (!(BIT(lru) & lru_mask)) | |
4154 | continue; | |
dd8657b6 SB |
4155 | if (tree) |
4156 | nr += memcg_page_state(memcg, NR_LRU_BASE + lru); | |
4157 | else | |
4158 | nr += memcg_page_state_local(memcg, NR_LRU_BASE + lru); | |
113b7dfd JW |
4159 | } |
4160 | return nr; | |
4161 | } | |
4162 | ||
2da8ca82 | 4163 | static int memcg_numa_stat_show(struct seq_file *m, void *v) |
406eb0c9 | 4164 | { |
25485de6 GT |
4165 | struct numa_stat { |
4166 | const char *name; | |
4167 | unsigned int lru_mask; | |
4168 | }; | |
4169 | ||
4170 | static const struct numa_stat stats[] = { | |
4171 | { "total", LRU_ALL }, | |
4172 | { "file", LRU_ALL_FILE }, | |
4173 | { "anon", LRU_ALL_ANON }, | |
4174 | { "unevictable", BIT(LRU_UNEVICTABLE) }, | |
4175 | }; | |
4176 | const struct numa_stat *stat; | |
406eb0c9 | 4177 | int nid; |
aa9694bb | 4178 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
406eb0c9 | 4179 | |
fd25a9e0 | 4180 | mem_cgroup_flush_stats(); |
2d146aa3 | 4181 | |
25485de6 | 4182 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
dd8657b6 SB |
4183 | seq_printf(m, "%s=%lu", stat->name, |
4184 | mem_cgroup_nr_lru_pages(memcg, stat->lru_mask, | |
4185 | false)); | |
4186 | for_each_node_state(nid, N_MEMORY) | |
4187 | seq_printf(m, " N%d=%lu", nid, | |
4188 | mem_cgroup_node_nr_lru_pages(memcg, nid, | |
4189 | stat->lru_mask, false)); | |
25485de6 | 4190 | seq_putc(m, '\n'); |
406eb0c9 | 4191 | } |
406eb0c9 | 4192 | |
071aee13 | 4193 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
dd8657b6 SB |
4194 | |
4195 | seq_printf(m, "hierarchical_%s=%lu", stat->name, | |
4196 | mem_cgroup_nr_lru_pages(memcg, stat->lru_mask, | |
4197 | true)); | |
4198 | for_each_node_state(nid, N_MEMORY) | |
4199 | seq_printf(m, " N%d=%lu", nid, | |
4200 | mem_cgroup_node_nr_lru_pages(memcg, nid, | |
4201 | stat->lru_mask, true)); | |
071aee13 | 4202 | seq_putc(m, '\n'); |
406eb0c9 | 4203 | } |
406eb0c9 | 4204 | |
406eb0c9 YH |
4205 | return 0; |
4206 | } | |
4207 | #endif /* CONFIG_NUMA */ | |
4208 | ||
c8713d0b | 4209 | static const unsigned int memcg1_stats[] = { |
0d1c2072 | 4210 | NR_FILE_PAGES, |
be5d0a74 | 4211 | NR_ANON_MAPPED, |
468c3982 JW |
4212 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
4213 | NR_ANON_THPS, | |
4214 | #endif | |
c8713d0b JW |
4215 | NR_SHMEM, |
4216 | NR_FILE_MAPPED, | |
4217 | NR_FILE_DIRTY, | |
4218 | NR_WRITEBACK, | |
e09b0b61 YS |
4219 | WORKINGSET_REFAULT_ANON, |
4220 | WORKINGSET_REFAULT_FILE, | |
72a14e82 | 4221 | #ifdef CONFIG_SWAP |
c8713d0b | 4222 | MEMCG_SWAP, |
72a14e82 LS |
4223 | NR_SWAPCACHE, |
4224 | #endif | |
c8713d0b JW |
4225 | }; |
4226 | ||
4227 | static const char *const memcg1_stat_names[] = { | |
4228 | "cache", | |
4229 | "rss", | |
468c3982 | 4230 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
c8713d0b | 4231 | "rss_huge", |
468c3982 | 4232 | #endif |
c8713d0b JW |
4233 | "shmem", |
4234 | "mapped_file", | |
4235 | "dirty", | |
4236 | "writeback", | |
e09b0b61 YS |
4237 | "workingset_refault_anon", |
4238 | "workingset_refault_file", | |
72a14e82 | 4239 | #ifdef CONFIG_SWAP |
c8713d0b | 4240 | "swap", |
72a14e82 LS |
4241 | "swapcached", |
4242 | #endif | |
c8713d0b JW |
4243 | }; |
4244 | ||
df0e53d0 | 4245 | /* Universal VM events cgroup1 shows, original sort order */ |
8dd53fd3 | 4246 | static const unsigned int memcg1_events[] = { |
df0e53d0 JW |
4247 | PGPGIN, |
4248 | PGPGOUT, | |
4249 | PGFAULT, | |
4250 | PGMAJFAULT, | |
4251 | }; | |
4252 | ||
dddb44ff | 4253 | static void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) |
d2ceb9b7 | 4254 | { |
3e32cb2e | 4255 | unsigned long memory, memsw; |
af7c4b0e JW |
4256 | struct mem_cgroup *mi; |
4257 | unsigned int i; | |
406eb0c9 | 4258 | |
71cd3113 | 4259 | BUILD_BUG_ON(ARRAY_SIZE(memcg1_stat_names) != ARRAY_SIZE(memcg1_stats)); |
70bc068c | 4260 | |
fd25a9e0 | 4261 | mem_cgroup_flush_stats(); |
2d146aa3 | 4262 | |
71cd3113 | 4263 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
468c3982 JW |
4264 | unsigned long nr; |
4265 | ||
ff841a06 YA |
4266 | nr = memcg_page_state_local_output(memcg, memcg1_stats[i]); |
4267 | seq_buf_printf(s, "%s %lu\n", memcg1_stat_names[i], nr); | |
1dd3a273 | 4268 | } |
7b854121 | 4269 | |
df0e53d0 | 4270 | for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) |
dddb44ff YA |
4271 | seq_buf_printf(s, "%s %lu\n", vm_event_name(memcg1_events[i]), |
4272 | memcg_events_local(memcg, memcg1_events[i])); | |
af7c4b0e JW |
4273 | |
4274 | for (i = 0; i < NR_LRU_LISTS; i++) | |
dddb44ff YA |
4275 | seq_buf_printf(s, "%s %lu\n", lru_list_name(i), |
4276 | memcg_page_state_local(memcg, NR_LRU_BASE + i) * | |
4277 | PAGE_SIZE); | |
af7c4b0e | 4278 | |
14067bb3 | 4279 | /* Hierarchical information */ |
3e32cb2e JW |
4280 | memory = memsw = PAGE_COUNTER_MAX; |
4281 | for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) { | |
15b42562 CD |
4282 | memory = min(memory, READ_ONCE(mi->memory.max)); |
4283 | memsw = min(memsw, READ_ONCE(mi->memsw.max)); | |
fee7b548 | 4284 | } |
dddb44ff YA |
4285 | seq_buf_printf(s, "hierarchical_memory_limit %llu\n", |
4286 | (u64)memory * PAGE_SIZE); | |
840ea53a LS |
4287 | seq_buf_printf(s, "hierarchical_memsw_limit %llu\n", |
4288 | (u64)memsw * PAGE_SIZE); | |
7f016ee8 | 4289 | |
8de7ecc6 | 4290 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
7de2e9f1 | 4291 | unsigned long nr; |
4292 | ||
ff841a06 | 4293 | nr = memcg_page_state_output(memcg, memcg1_stats[i]); |
dddb44ff | 4294 | seq_buf_printf(s, "total_%s %llu\n", memcg1_stat_names[i], |
ff841a06 | 4295 | (u64)nr); |
af7c4b0e JW |
4296 | } |
4297 | ||
8de7ecc6 | 4298 | for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) |
dddb44ff YA |
4299 | seq_buf_printf(s, "total_%s %llu\n", |
4300 | vm_event_name(memcg1_events[i]), | |
4301 | (u64)memcg_events(memcg, memcg1_events[i])); | |
af7c4b0e | 4302 | |
8de7ecc6 | 4303 | for (i = 0; i < NR_LRU_LISTS; i++) |
dddb44ff YA |
4304 | seq_buf_printf(s, "total_%s %llu\n", lru_list_name(i), |
4305 | (u64)memcg_page_state(memcg, NR_LRU_BASE + i) * | |
4306 | PAGE_SIZE); | |
14067bb3 | 4307 | |
7f016ee8 | 4308 | #ifdef CONFIG_DEBUG_VM |
7f016ee8 | 4309 | { |
ef8f2327 MG |
4310 | pg_data_t *pgdat; |
4311 | struct mem_cgroup_per_node *mz; | |
1431d4d1 JW |
4312 | unsigned long anon_cost = 0; |
4313 | unsigned long file_cost = 0; | |
7f016ee8 | 4314 | |
ef8f2327 | 4315 | for_each_online_pgdat(pgdat) { |
a3747b53 | 4316 | mz = memcg->nodeinfo[pgdat->node_id]; |
7f016ee8 | 4317 | |
1431d4d1 JW |
4318 | anon_cost += mz->lruvec.anon_cost; |
4319 | file_cost += mz->lruvec.file_cost; | |
ef8f2327 | 4320 | } |
dddb44ff YA |
4321 | seq_buf_printf(s, "anon_cost %lu\n", anon_cost); |
4322 | seq_buf_printf(s, "file_cost %lu\n", file_cost); | |
7f016ee8 KM |
4323 | } |
4324 | #endif | |
d2ceb9b7 KH |
4325 | } |
4326 | ||
182446d0 TH |
4327 | static u64 mem_cgroup_swappiness_read(struct cgroup_subsys_state *css, |
4328 | struct cftype *cft) | |
a7885eb8 | 4329 | { |
182446d0 | 4330 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 4331 | |
1f4c025b | 4332 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
4333 | } |
4334 | ||
182446d0 TH |
4335 | static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, |
4336 | struct cftype *cft, u64 val) | |
a7885eb8 | 4337 | { |
182446d0 | 4338 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 4339 | |
37bc3cb9 | 4340 | if (val > 200) |
a7885eb8 KM |
4341 | return -EINVAL; |
4342 | ||
a4792030 | 4343 | if (!mem_cgroup_is_root(memcg)) |
82b3aa26 | 4344 | WRITE_ONCE(memcg->swappiness, val); |
3dae7fec | 4345 | else |
82b3aa26 | 4346 | WRITE_ONCE(vm_swappiness, val); |
068b38c1 | 4347 | |
a7885eb8 KM |
4348 | return 0; |
4349 | } | |
4350 | ||
2e72b634 KS |
4351 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
4352 | { | |
4353 | struct mem_cgroup_threshold_ary *t; | |
3e32cb2e | 4354 | unsigned long usage; |
2e72b634 KS |
4355 | int i; |
4356 | ||
4357 | rcu_read_lock(); | |
4358 | if (!swap) | |
2c488db2 | 4359 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 4360 | else |
2c488db2 | 4361 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
4362 | |
4363 | if (!t) | |
4364 | goto unlock; | |
4365 | ||
ce00a967 | 4366 | usage = mem_cgroup_usage(memcg, swap); |
2e72b634 KS |
4367 | |
4368 | /* | |
748dad36 | 4369 | * current_threshold points to threshold just below or equal to usage. |
2e72b634 KS |
4370 | * If it's not true, a threshold was crossed after last |
4371 | * call of __mem_cgroup_threshold(). | |
4372 | */ | |
5407a562 | 4373 | i = t->current_threshold; |
2e72b634 KS |
4374 | |
4375 | /* | |
4376 | * Iterate backward over array of thresholds starting from | |
4377 | * current_threshold and check if a threshold is crossed. | |
4378 | * If none of thresholds below usage is crossed, we read | |
4379 | * only one element of the array here. | |
4380 | */ | |
4381 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
4382 | eventfd_signal(t->entries[i].eventfd, 1); | |
4383 | ||
4384 | /* i = current_threshold + 1 */ | |
4385 | i++; | |
4386 | ||
4387 | /* | |
4388 | * Iterate forward over array of thresholds starting from | |
4389 | * current_threshold+1 and check if a threshold is crossed. | |
4390 | * If none of thresholds above usage is crossed, we read | |
4391 | * only one element of the array here. | |
4392 | */ | |
4393 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
4394 | eventfd_signal(t->entries[i].eventfd, 1); | |
4395 | ||
4396 | /* Update current_threshold */ | |
5407a562 | 4397 | t->current_threshold = i - 1; |
2e72b634 KS |
4398 | unlock: |
4399 | rcu_read_unlock(); | |
4400 | } | |
4401 | ||
4402 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
4403 | { | |
ad4ca5f4 KS |
4404 | while (memcg) { |
4405 | __mem_cgroup_threshold(memcg, false); | |
7941d214 | 4406 | if (do_memsw_account()) |
ad4ca5f4 KS |
4407 | __mem_cgroup_threshold(memcg, true); |
4408 | ||
4409 | memcg = parent_mem_cgroup(memcg); | |
4410 | } | |
2e72b634 KS |
4411 | } |
4412 | ||
4413 | static int compare_thresholds(const void *a, const void *b) | |
4414 | { | |
4415 | const struct mem_cgroup_threshold *_a = a; | |
4416 | const struct mem_cgroup_threshold *_b = b; | |
4417 | ||
2bff24a3 GT |
4418 | if (_a->threshold > _b->threshold) |
4419 | return 1; | |
4420 | ||
4421 | if (_a->threshold < _b->threshold) | |
4422 | return -1; | |
4423 | ||
4424 | return 0; | |
2e72b634 KS |
4425 | } |
4426 | ||
c0ff4b85 | 4427 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg) |
9490ff27 KH |
4428 | { |
4429 | struct mem_cgroup_eventfd_list *ev; | |
4430 | ||
2bcf2e92 MH |
4431 | spin_lock(&memcg_oom_lock); |
4432 | ||
c0ff4b85 | 4433 | list_for_each_entry(ev, &memcg->oom_notify, list) |
9490ff27 | 4434 | eventfd_signal(ev->eventfd, 1); |
2bcf2e92 MH |
4435 | |
4436 | spin_unlock(&memcg_oom_lock); | |
9490ff27 KH |
4437 | return 0; |
4438 | } | |
4439 | ||
c0ff4b85 | 4440 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) |
9490ff27 | 4441 | { |
7d74b06f KH |
4442 | struct mem_cgroup *iter; |
4443 | ||
c0ff4b85 | 4444 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 4445 | mem_cgroup_oom_notify_cb(iter); |
9490ff27 KH |
4446 | } |
4447 | ||
59b6f873 | 4448 | static int __mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 | 4449 | struct eventfd_ctx *eventfd, const char *args, enum res_type type) |
2e72b634 | 4450 | { |
2c488db2 KS |
4451 | struct mem_cgroup_thresholds *thresholds; |
4452 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e JW |
4453 | unsigned long threshold; |
4454 | unsigned long usage; | |
2c488db2 | 4455 | int i, size, ret; |
2e72b634 | 4456 | |
650c5e56 | 4457 | ret = page_counter_memparse(args, "-1", &threshold); |
2e72b634 KS |
4458 | if (ret) |
4459 | return ret; | |
4460 | ||
4461 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 4462 | |
05b84301 | 4463 | if (type == _MEM) { |
2c488db2 | 4464 | thresholds = &memcg->thresholds; |
ce00a967 | 4465 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 4466 | } else if (type == _MEMSWAP) { |
2c488db2 | 4467 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 4468 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 4469 | } else |
2e72b634 KS |
4470 | BUG(); |
4471 | ||
2e72b634 | 4472 | /* Check if a threshold crossed before adding a new one */ |
2c488db2 | 4473 | if (thresholds->primary) |
2e72b634 KS |
4474 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4475 | ||
2c488db2 | 4476 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
4477 | |
4478 | /* Allocate memory for new array of thresholds */ | |
67b8046f | 4479 | new = kmalloc(struct_size(new, entries, size), GFP_KERNEL); |
2c488db2 | 4480 | if (!new) { |
2e72b634 KS |
4481 | ret = -ENOMEM; |
4482 | goto unlock; | |
4483 | } | |
2c488db2 | 4484 | new->size = size; |
2e72b634 KS |
4485 | |
4486 | /* Copy thresholds (if any) to new array */ | |
e90342e6 GS |
4487 | if (thresholds->primary) |
4488 | memcpy(new->entries, thresholds->primary->entries, | |
4489 | flex_array_size(new, entries, size - 1)); | |
2c488db2 | 4490 | |
2e72b634 | 4491 | /* Add new threshold */ |
2c488db2 KS |
4492 | new->entries[size - 1].eventfd = eventfd; |
4493 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
4494 | |
4495 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
61e604e6 | 4496 | sort(new->entries, size, sizeof(*new->entries), |
2e72b634 KS |
4497 | compare_thresholds, NULL); |
4498 | ||
4499 | /* Find current threshold */ | |
2c488db2 | 4500 | new->current_threshold = -1; |
2e72b634 | 4501 | for (i = 0; i < size; i++) { |
748dad36 | 4502 | if (new->entries[i].threshold <= usage) { |
2e72b634 | 4503 | /* |
2c488db2 KS |
4504 | * new->current_threshold will not be used until |
4505 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
4506 | * it here. |
4507 | */ | |
2c488db2 | 4508 | ++new->current_threshold; |
748dad36 SZ |
4509 | } else |
4510 | break; | |
2e72b634 KS |
4511 | } |
4512 | ||
2c488db2 KS |
4513 | /* Free old spare buffer and save old primary buffer as spare */ |
4514 | kfree(thresholds->spare); | |
4515 | thresholds->spare = thresholds->primary; | |
4516 | ||
4517 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4518 | |
907860ed | 4519 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4520 | synchronize_rcu(); |
4521 | ||
2e72b634 KS |
4522 | unlock: |
4523 | mutex_unlock(&memcg->thresholds_lock); | |
4524 | ||
4525 | return ret; | |
4526 | } | |
4527 | ||
59b6f873 | 4528 | static int mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4529 | struct eventfd_ctx *eventfd, const char *args) |
4530 | { | |
59b6f873 | 4531 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEM); |
347c4a87 TH |
4532 | } |
4533 | ||
59b6f873 | 4534 | static int memsw_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4535 | struct eventfd_ctx *eventfd, const char *args) |
4536 | { | |
59b6f873 | 4537 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEMSWAP); |
347c4a87 TH |
4538 | } |
4539 | ||
59b6f873 | 4540 | static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 4541 | struct eventfd_ctx *eventfd, enum res_type type) |
2e72b634 | 4542 | { |
2c488db2 KS |
4543 | struct mem_cgroup_thresholds *thresholds; |
4544 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e | 4545 | unsigned long usage; |
7d36665a | 4546 | int i, j, size, entries; |
2e72b634 KS |
4547 | |
4548 | mutex_lock(&memcg->thresholds_lock); | |
05b84301 JW |
4549 | |
4550 | if (type == _MEM) { | |
2c488db2 | 4551 | thresholds = &memcg->thresholds; |
ce00a967 | 4552 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 4553 | } else if (type == _MEMSWAP) { |
2c488db2 | 4554 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 4555 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 4556 | } else |
2e72b634 KS |
4557 | BUG(); |
4558 | ||
371528ca AV |
4559 | if (!thresholds->primary) |
4560 | goto unlock; | |
4561 | ||
2e72b634 KS |
4562 | /* Check if a threshold crossed before removing */ |
4563 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
4564 | ||
4565 | /* Calculate new number of threshold */ | |
7d36665a | 4566 | size = entries = 0; |
2c488db2 KS |
4567 | for (i = 0; i < thresholds->primary->size; i++) { |
4568 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 | 4569 | size++; |
7d36665a CX |
4570 | else |
4571 | entries++; | |
2e72b634 KS |
4572 | } |
4573 | ||
2c488db2 | 4574 | new = thresholds->spare; |
907860ed | 4575 | |
7d36665a CX |
4576 | /* If no items related to eventfd have been cleared, nothing to do */ |
4577 | if (!entries) | |
4578 | goto unlock; | |
4579 | ||
2e72b634 KS |
4580 | /* Set thresholds array to NULL if we don't have thresholds */ |
4581 | if (!size) { | |
2c488db2 KS |
4582 | kfree(new); |
4583 | new = NULL; | |
907860ed | 4584 | goto swap_buffers; |
2e72b634 KS |
4585 | } |
4586 | ||
2c488db2 | 4587 | new->size = size; |
2e72b634 KS |
4588 | |
4589 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
4590 | new->current_threshold = -1; |
4591 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
4592 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
4593 | continue; |
4594 | ||
2c488db2 | 4595 | new->entries[j] = thresholds->primary->entries[i]; |
748dad36 | 4596 | if (new->entries[j].threshold <= usage) { |
2e72b634 | 4597 | /* |
2c488db2 | 4598 | * new->current_threshold will not be used |
2e72b634 KS |
4599 | * until rcu_assign_pointer(), so it's safe to increment |
4600 | * it here. | |
4601 | */ | |
2c488db2 | 4602 | ++new->current_threshold; |
2e72b634 KS |
4603 | } |
4604 | j++; | |
4605 | } | |
4606 | ||
907860ed | 4607 | swap_buffers: |
2c488db2 KS |
4608 | /* Swap primary and spare array */ |
4609 | thresholds->spare = thresholds->primary; | |
8c757763 | 4610 | |
2c488db2 | 4611 | rcu_assign_pointer(thresholds->primary, new); |
2e72b634 | 4612 | |
907860ed | 4613 | /* To be sure that nobody uses thresholds */ |
2e72b634 | 4614 | synchronize_rcu(); |
6611d8d7 MC |
4615 | |
4616 | /* If all events are unregistered, free the spare array */ | |
4617 | if (!new) { | |
4618 | kfree(thresholds->spare); | |
4619 | thresholds->spare = NULL; | |
4620 | } | |
371528ca | 4621 | unlock: |
2e72b634 | 4622 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 4623 | } |
c1e862c1 | 4624 | |
59b6f873 | 4625 | static void mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4626 | struct eventfd_ctx *eventfd) |
4627 | { | |
59b6f873 | 4628 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEM); |
347c4a87 TH |
4629 | } |
4630 | ||
59b6f873 | 4631 | static void memsw_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4632 | struct eventfd_ctx *eventfd) |
4633 | { | |
59b6f873 | 4634 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEMSWAP); |
347c4a87 TH |
4635 | } |
4636 | ||
59b6f873 | 4637 | static int mem_cgroup_oom_register_event(struct mem_cgroup *memcg, |
347c4a87 | 4638 | struct eventfd_ctx *eventfd, const char *args) |
9490ff27 | 4639 | { |
9490ff27 | 4640 | struct mem_cgroup_eventfd_list *event; |
9490ff27 | 4641 | |
9490ff27 KH |
4642 | event = kmalloc(sizeof(*event), GFP_KERNEL); |
4643 | if (!event) | |
4644 | return -ENOMEM; | |
4645 | ||
1af8efe9 | 4646 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4647 | |
4648 | event->eventfd = eventfd; | |
4649 | list_add(&event->list, &memcg->oom_notify); | |
4650 | ||
4651 | /* already in OOM ? */ | |
c2b42d3c | 4652 | if (memcg->under_oom) |
9490ff27 | 4653 | eventfd_signal(eventfd, 1); |
1af8efe9 | 4654 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4655 | |
4656 | return 0; | |
4657 | } | |
4658 | ||
59b6f873 | 4659 | static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 4660 | struct eventfd_ctx *eventfd) |
9490ff27 | 4661 | { |
9490ff27 | 4662 | struct mem_cgroup_eventfd_list *ev, *tmp; |
9490ff27 | 4663 | |
1af8efe9 | 4664 | spin_lock(&memcg_oom_lock); |
9490ff27 | 4665 | |
c0ff4b85 | 4666 | list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) { |
9490ff27 KH |
4667 | if (ev->eventfd == eventfd) { |
4668 | list_del(&ev->list); | |
4669 | kfree(ev); | |
4670 | } | |
4671 | } | |
4672 | ||
1af8efe9 | 4673 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4674 | } |
4675 | ||
2da8ca82 | 4676 | static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v) |
3c11ecf4 | 4677 | { |
aa9694bb | 4678 | struct mem_cgroup *memcg = mem_cgroup_from_seq(sf); |
3c11ecf4 | 4679 | |
17c56de6 | 4680 | seq_printf(sf, "oom_kill_disable %d\n", READ_ONCE(memcg->oom_kill_disable)); |
c2b42d3c | 4681 | seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom); |
fe6bdfc8 RG |
4682 | seq_printf(sf, "oom_kill %lu\n", |
4683 | atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL])); | |
3c11ecf4 KH |
4684 | return 0; |
4685 | } | |
4686 | ||
182446d0 | 4687 | static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css, |
3c11ecf4 KH |
4688 | struct cftype *cft, u64 val) |
4689 | { | |
182446d0 | 4690 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3c11ecf4 KH |
4691 | |
4692 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
a4792030 | 4693 | if (mem_cgroup_is_root(memcg) || !((val == 0) || (val == 1))) |
3c11ecf4 KH |
4694 | return -EINVAL; |
4695 | ||
17c56de6 | 4696 | WRITE_ONCE(memcg->oom_kill_disable, val); |
4d845ebf | 4697 | if (!val) |
c0ff4b85 | 4698 | memcg_oom_recover(memcg); |
3dae7fec | 4699 | |
3c11ecf4 KH |
4700 | return 0; |
4701 | } | |
4702 | ||
52ebea74 TH |
4703 | #ifdef CONFIG_CGROUP_WRITEBACK |
4704 | ||
3a8e9ac8 TH |
4705 | #include <trace/events/writeback.h> |
4706 | ||
841710aa TH |
4707 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) |
4708 | { | |
4709 | return wb_domain_init(&memcg->cgwb_domain, gfp); | |
4710 | } | |
4711 | ||
4712 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
4713 | { | |
4714 | wb_domain_exit(&memcg->cgwb_domain); | |
4715 | } | |
4716 | ||
2529bb3a TH |
4717 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
4718 | { | |
4719 | wb_domain_size_changed(&memcg->cgwb_domain); | |
4720 | } | |
4721 | ||
841710aa TH |
4722 | struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb) |
4723 | { | |
4724 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4725 | ||
4726 | if (!memcg->css.parent) | |
4727 | return NULL; | |
4728 | ||
4729 | return &memcg->cgwb_domain; | |
4730 | } | |
4731 | ||
c2aa723a TH |
4732 | /** |
4733 | * mem_cgroup_wb_stats - retrieve writeback related stats from its memcg | |
4734 | * @wb: bdi_writeback in question | |
c5edf9cd TH |
4735 | * @pfilepages: out parameter for number of file pages |
4736 | * @pheadroom: out parameter for number of allocatable pages according to memcg | |
c2aa723a TH |
4737 | * @pdirty: out parameter for number of dirty pages |
4738 | * @pwriteback: out parameter for number of pages under writeback | |
4739 | * | |
c5edf9cd TH |
4740 | * Determine the numbers of file, headroom, dirty, and writeback pages in |
4741 | * @wb's memcg. File, dirty and writeback are self-explanatory. Headroom | |
4742 | * is a bit more involved. | |
c2aa723a | 4743 | * |
c5edf9cd TH |
4744 | * A memcg's headroom is "min(max, high) - used". In the hierarchy, the |
4745 | * headroom is calculated as the lowest headroom of itself and the | |
4746 | * ancestors. Note that this doesn't consider the actual amount of | |
4747 | * available memory in the system. The caller should further cap | |
4748 | * *@pheadroom accordingly. | |
c2aa723a | 4749 | */ |
c5edf9cd TH |
4750 | void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, |
4751 | unsigned long *pheadroom, unsigned long *pdirty, | |
4752 | unsigned long *pwriteback) | |
c2aa723a TH |
4753 | { |
4754 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4755 | struct mem_cgroup *parent; | |
c2aa723a | 4756 | |
190409ca | 4757 | mem_cgroup_flush_stats(); |
c2aa723a | 4758 | |
2d146aa3 JW |
4759 | *pdirty = memcg_page_state(memcg, NR_FILE_DIRTY); |
4760 | *pwriteback = memcg_page_state(memcg, NR_WRITEBACK); | |
4761 | *pfilepages = memcg_page_state(memcg, NR_INACTIVE_FILE) + | |
4762 | memcg_page_state(memcg, NR_ACTIVE_FILE); | |
c2aa723a | 4763 | |
2d146aa3 | 4764 | *pheadroom = PAGE_COUNTER_MAX; |
c2aa723a | 4765 | while ((parent = parent_mem_cgroup(memcg))) { |
15b42562 | 4766 | unsigned long ceiling = min(READ_ONCE(memcg->memory.max), |
d1663a90 | 4767 | READ_ONCE(memcg->memory.high)); |
c2aa723a TH |
4768 | unsigned long used = page_counter_read(&memcg->memory); |
4769 | ||
c5edf9cd | 4770 | *pheadroom = min(*pheadroom, ceiling - min(ceiling, used)); |
c2aa723a TH |
4771 | memcg = parent; |
4772 | } | |
c2aa723a TH |
4773 | } |
4774 | ||
97b27821 TH |
4775 | /* |
4776 | * Foreign dirty flushing | |
4777 | * | |
4778 | * There's an inherent mismatch between memcg and writeback. The former | |
f0953a1b | 4779 | * tracks ownership per-page while the latter per-inode. This was a |
97b27821 TH |
4780 | * deliberate design decision because honoring per-page ownership in the |
4781 | * writeback path is complicated, may lead to higher CPU and IO overheads | |
4782 | * and deemed unnecessary given that write-sharing an inode across | |
4783 | * different cgroups isn't a common use-case. | |
4784 | * | |
4785 | * Combined with inode majority-writer ownership switching, this works well | |
4786 | * enough in most cases but there are some pathological cases. For | |
4787 | * example, let's say there are two cgroups A and B which keep writing to | |
4788 | * different but confined parts of the same inode. B owns the inode and | |
4789 | * A's memory is limited far below B's. A's dirty ratio can rise enough to | |
4790 | * trigger balance_dirty_pages() sleeps but B's can be low enough to avoid | |
4791 | * triggering background writeback. A will be slowed down without a way to | |
4792 | * make writeback of the dirty pages happen. | |
4793 | * | |
f0953a1b | 4794 | * Conditions like the above can lead to a cgroup getting repeatedly and |
97b27821 | 4795 | * severely throttled after making some progress after each |
f0953a1b | 4796 | * dirty_expire_interval while the underlying IO device is almost |
97b27821 TH |
4797 | * completely idle. |
4798 | * | |
4799 | * Solving this problem completely requires matching the ownership tracking | |
4800 | * granularities between memcg and writeback in either direction. However, | |
4801 | * the more egregious behaviors can be avoided by simply remembering the | |
4802 | * most recent foreign dirtying events and initiating remote flushes on | |
4803 | * them when local writeback isn't enough to keep the memory clean enough. | |
4804 | * | |
4805 | * The following two functions implement such mechanism. When a foreign | |
4806 | * page - a page whose memcg and writeback ownerships don't match - is | |
4807 | * dirtied, mem_cgroup_track_foreign_dirty() records the inode owning | |
4808 | * bdi_writeback on the page owning memcg. When balance_dirty_pages() | |
4809 | * decides that the memcg needs to sleep due to high dirty ratio, it calls | |
4810 | * mem_cgroup_flush_foreign() which queues writeback on the recorded | |
4811 | * foreign bdi_writebacks which haven't expired. Both the numbers of | |
4812 | * recorded bdi_writebacks and concurrent in-flight foreign writebacks are | |
4813 | * limited to MEMCG_CGWB_FRN_CNT. | |
4814 | * | |
4815 | * The mechanism only remembers IDs and doesn't hold any object references. | |
4816 | * As being wrong occasionally doesn't matter, updates and accesses to the | |
4817 | * records are lockless and racy. | |
4818 | */ | |
9d8053fc | 4819 | void mem_cgroup_track_foreign_dirty_slowpath(struct folio *folio, |
97b27821 TH |
4820 | struct bdi_writeback *wb) |
4821 | { | |
9d8053fc | 4822 | struct mem_cgroup *memcg = folio_memcg(folio); |
97b27821 TH |
4823 | struct memcg_cgwb_frn *frn; |
4824 | u64 now = get_jiffies_64(); | |
4825 | u64 oldest_at = now; | |
4826 | int oldest = -1; | |
4827 | int i; | |
4828 | ||
9d8053fc | 4829 | trace_track_foreign_dirty(folio, wb); |
3a8e9ac8 | 4830 | |
97b27821 TH |
4831 | /* |
4832 | * Pick the slot to use. If there is already a slot for @wb, keep | |
4833 | * using it. If not replace the oldest one which isn't being | |
4834 | * written out. | |
4835 | */ | |
4836 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) { | |
4837 | frn = &memcg->cgwb_frn[i]; | |
4838 | if (frn->bdi_id == wb->bdi->id && | |
4839 | frn->memcg_id == wb->memcg_css->id) | |
4840 | break; | |
4841 | if (time_before64(frn->at, oldest_at) && | |
4842 | atomic_read(&frn->done.cnt) == 1) { | |
4843 | oldest = i; | |
4844 | oldest_at = frn->at; | |
4845 | } | |
4846 | } | |
4847 | ||
4848 | if (i < MEMCG_CGWB_FRN_CNT) { | |
4849 | /* | |
4850 | * Re-using an existing one. Update timestamp lazily to | |
4851 | * avoid making the cacheline hot. We want them to be | |
4852 | * reasonably up-to-date and significantly shorter than | |
4853 | * dirty_expire_interval as that's what expires the record. | |
4854 | * Use the shorter of 1s and dirty_expire_interval / 8. | |
4855 | */ | |
4856 | unsigned long update_intv = | |
4857 | min_t(unsigned long, HZ, | |
4858 | msecs_to_jiffies(dirty_expire_interval * 10) / 8); | |
4859 | ||
4860 | if (time_before64(frn->at, now - update_intv)) | |
4861 | frn->at = now; | |
4862 | } else if (oldest >= 0) { | |
4863 | /* replace the oldest free one */ | |
4864 | frn = &memcg->cgwb_frn[oldest]; | |
4865 | frn->bdi_id = wb->bdi->id; | |
4866 | frn->memcg_id = wb->memcg_css->id; | |
4867 | frn->at = now; | |
4868 | } | |
4869 | } | |
4870 | ||
4871 | /* issue foreign writeback flushes for recorded foreign dirtying events */ | |
4872 | void mem_cgroup_flush_foreign(struct bdi_writeback *wb) | |
4873 | { | |
4874 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4875 | unsigned long intv = msecs_to_jiffies(dirty_expire_interval * 10); | |
4876 | u64 now = jiffies_64; | |
4877 | int i; | |
4878 | ||
4879 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) { | |
4880 | struct memcg_cgwb_frn *frn = &memcg->cgwb_frn[i]; | |
4881 | ||
4882 | /* | |
4883 | * If the record is older than dirty_expire_interval, | |
4884 | * writeback on it has already started. No need to kick it | |
4885 | * off again. Also, don't start a new one if there's | |
4886 | * already one in flight. | |
4887 | */ | |
4888 | if (time_after64(frn->at, now - intv) && | |
4889 | atomic_read(&frn->done.cnt) == 1) { | |
4890 | frn->at = 0; | |
3a8e9ac8 | 4891 | trace_flush_foreign(wb, frn->bdi_id, frn->memcg_id); |
7490a2d2 | 4892 | cgroup_writeback_by_id(frn->bdi_id, frn->memcg_id, |
97b27821 TH |
4893 | WB_REASON_FOREIGN_FLUSH, |
4894 | &frn->done); | |
4895 | } | |
4896 | } | |
4897 | } | |
4898 | ||
841710aa TH |
4899 | #else /* CONFIG_CGROUP_WRITEBACK */ |
4900 | ||
4901 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) | |
4902 | { | |
4903 | return 0; | |
4904 | } | |
4905 | ||
4906 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
4907 | { | |
4908 | } | |
4909 | ||
2529bb3a TH |
4910 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
4911 | { | |
4912 | } | |
4913 | ||
52ebea74 TH |
4914 | #endif /* CONFIG_CGROUP_WRITEBACK */ |
4915 | ||
3bc942f3 TH |
4916 | /* |
4917 | * DO NOT USE IN NEW FILES. | |
4918 | * | |
4919 | * "cgroup.event_control" implementation. | |
4920 | * | |
4921 | * This is way over-engineered. It tries to support fully configurable | |
4922 | * events for each user. Such level of flexibility is completely | |
4923 | * unnecessary especially in the light of the planned unified hierarchy. | |
4924 | * | |
4925 | * Please deprecate this and replace with something simpler if at all | |
4926 | * possible. | |
4927 | */ | |
4928 | ||
79bd9814 TH |
4929 | /* |
4930 | * Unregister event and free resources. | |
4931 | * | |
4932 | * Gets called from workqueue. | |
4933 | */ | |
3bc942f3 | 4934 | static void memcg_event_remove(struct work_struct *work) |
79bd9814 | 4935 | { |
3bc942f3 TH |
4936 | struct mem_cgroup_event *event = |
4937 | container_of(work, struct mem_cgroup_event, remove); | |
59b6f873 | 4938 | struct mem_cgroup *memcg = event->memcg; |
79bd9814 TH |
4939 | |
4940 | remove_wait_queue(event->wqh, &event->wait); | |
4941 | ||
59b6f873 | 4942 | event->unregister_event(memcg, event->eventfd); |
79bd9814 TH |
4943 | |
4944 | /* Notify userspace the event is going away. */ | |
4945 | eventfd_signal(event->eventfd, 1); | |
4946 | ||
4947 | eventfd_ctx_put(event->eventfd); | |
4948 | kfree(event); | |
59b6f873 | 4949 | css_put(&memcg->css); |
79bd9814 TH |
4950 | } |
4951 | ||
4952 | /* | |
a9a08845 | 4953 | * Gets called on EPOLLHUP on eventfd when user closes it. |
79bd9814 TH |
4954 | * |
4955 | * Called with wqh->lock held and interrupts disabled. | |
4956 | */ | |
ac6424b9 | 4957 | static int memcg_event_wake(wait_queue_entry_t *wait, unsigned mode, |
3bc942f3 | 4958 | int sync, void *key) |
79bd9814 | 4959 | { |
3bc942f3 TH |
4960 | struct mem_cgroup_event *event = |
4961 | container_of(wait, struct mem_cgroup_event, wait); | |
59b6f873 | 4962 | struct mem_cgroup *memcg = event->memcg; |
3ad6f93e | 4963 | __poll_t flags = key_to_poll(key); |
79bd9814 | 4964 | |
a9a08845 | 4965 | if (flags & EPOLLHUP) { |
79bd9814 TH |
4966 | /* |
4967 | * If the event has been detached at cgroup removal, we | |
4968 | * can simply return knowing the other side will cleanup | |
4969 | * for us. | |
4970 | * | |
4971 | * We can't race against event freeing since the other | |
4972 | * side will require wqh->lock via remove_wait_queue(), | |
4973 | * which we hold. | |
4974 | */ | |
fba94807 | 4975 | spin_lock(&memcg->event_list_lock); |
79bd9814 TH |
4976 | if (!list_empty(&event->list)) { |
4977 | list_del_init(&event->list); | |
4978 | /* | |
4979 | * We are in atomic context, but cgroup_event_remove() | |
4980 | * may sleep, so we have to call it in workqueue. | |
4981 | */ | |
4982 | schedule_work(&event->remove); | |
4983 | } | |
fba94807 | 4984 | spin_unlock(&memcg->event_list_lock); |
79bd9814 TH |
4985 | } |
4986 | ||
4987 | return 0; | |
4988 | } | |
4989 | ||
3bc942f3 | 4990 | static void memcg_event_ptable_queue_proc(struct file *file, |
79bd9814 TH |
4991 | wait_queue_head_t *wqh, poll_table *pt) |
4992 | { | |
3bc942f3 TH |
4993 | struct mem_cgroup_event *event = |
4994 | container_of(pt, struct mem_cgroup_event, pt); | |
79bd9814 TH |
4995 | |
4996 | event->wqh = wqh; | |
4997 | add_wait_queue(wqh, &event->wait); | |
4998 | } | |
4999 | ||
5000 | /* | |
3bc942f3 TH |
5001 | * DO NOT USE IN NEW FILES. |
5002 | * | |
79bd9814 TH |
5003 | * Parse input and register new cgroup event handler. |
5004 | * | |
5005 | * Input must be in format '<event_fd> <control_fd> <args>'. | |
5006 | * Interpretation of args is defined by control file implementation. | |
5007 | */ | |
451af504 TH |
5008 | static ssize_t memcg_write_event_control(struct kernfs_open_file *of, |
5009 | char *buf, size_t nbytes, loff_t off) | |
79bd9814 | 5010 | { |
451af504 | 5011 | struct cgroup_subsys_state *css = of_css(of); |
fba94807 | 5012 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 5013 | struct mem_cgroup_event *event; |
79bd9814 TH |
5014 | struct cgroup_subsys_state *cfile_css; |
5015 | unsigned int efd, cfd; | |
5016 | struct fd efile; | |
5017 | struct fd cfile; | |
4a7ba45b | 5018 | struct dentry *cdentry; |
fba94807 | 5019 | const char *name; |
79bd9814 TH |
5020 | char *endp; |
5021 | int ret; | |
5022 | ||
2343e88d SAS |
5023 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) |
5024 | return -EOPNOTSUPP; | |
5025 | ||
451af504 TH |
5026 | buf = strstrip(buf); |
5027 | ||
5028 | efd = simple_strtoul(buf, &endp, 10); | |
79bd9814 TH |
5029 | if (*endp != ' ') |
5030 | return -EINVAL; | |
451af504 | 5031 | buf = endp + 1; |
79bd9814 | 5032 | |
451af504 | 5033 | cfd = simple_strtoul(buf, &endp, 10); |
79bd9814 TH |
5034 | if ((*endp != ' ') && (*endp != '\0')) |
5035 | return -EINVAL; | |
451af504 | 5036 | buf = endp + 1; |
79bd9814 TH |
5037 | |
5038 | event = kzalloc(sizeof(*event), GFP_KERNEL); | |
5039 | if (!event) | |
5040 | return -ENOMEM; | |
5041 | ||
59b6f873 | 5042 | event->memcg = memcg; |
79bd9814 | 5043 | INIT_LIST_HEAD(&event->list); |
3bc942f3 TH |
5044 | init_poll_funcptr(&event->pt, memcg_event_ptable_queue_proc); |
5045 | init_waitqueue_func_entry(&event->wait, memcg_event_wake); | |
5046 | INIT_WORK(&event->remove, memcg_event_remove); | |
79bd9814 TH |
5047 | |
5048 | efile = fdget(efd); | |
5049 | if (!efile.file) { | |
5050 | ret = -EBADF; | |
5051 | goto out_kfree; | |
5052 | } | |
5053 | ||
5054 | event->eventfd = eventfd_ctx_fileget(efile.file); | |
5055 | if (IS_ERR(event->eventfd)) { | |
5056 | ret = PTR_ERR(event->eventfd); | |
5057 | goto out_put_efile; | |
5058 | } | |
5059 | ||
5060 | cfile = fdget(cfd); | |
5061 | if (!cfile.file) { | |
5062 | ret = -EBADF; | |
5063 | goto out_put_eventfd; | |
5064 | } | |
5065 | ||
5066 | /* the process need read permission on control file */ | |
5067 | /* AV: shouldn't we check that it's been opened for read instead? */ | |
02f92b38 | 5068 | ret = file_permission(cfile.file, MAY_READ); |
79bd9814 TH |
5069 | if (ret < 0) |
5070 | goto out_put_cfile; | |
5071 | ||
4a7ba45b TH |
5072 | /* |
5073 | * The control file must be a regular cgroup1 file. As a regular cgroup | |
5074 | * file can't be renamed, it's safe to access its name afterwards. | |
5075 | */ | |
5076 | cdentry = cfile.file->f_path.dentry; | |
5077 | if (cdentry->d_sb->s_type != &cgroup_fs_type || !d_is_reg(cdentry)) { | |
5078 | ret = -EINVAL; | |
5079 | goto out_put_cfile; | |
5080 | } | |
5081 | ||
fba94807 TH |
5082 | /* |
5083 | * Determine the event callbacks and set them in @event. This used | |
5084 | * to be done via struct cftype but cgroup core no longer knows | |
5085 | * about these events. The following is crude but the whole thing | |
5086 | * is for compatibility anyway. | |
3bc942f3 TH |
5087 | * |
5088 | * DO NOT ADD NEW FILES. | |
fba94807 | 5089 | */ |
4a7ba45b | 5090 | name = cdentry->d_name.name; |
fba94807 TH |
5091 | |
5092 | if (!strcmp(name, "memory.usage_in_bytes")) { | |
5093 | event->register_event = mem_cgroup_usage_register_event; | |
5094 | event->unregister_event = mem_cgroup_usage_unregister_event; | |
5095 | } else if (!strcmp(name, "memory.oom_control")) { | |
5096 | event->register_event = mem_cgroup_oom_register_event; | |
5097 | event->unregister_event = mem_cgroup_oom_unregister_event; | |
5098 | } else if (!strcmp(name, "memory.pressure_level")) { | |
5099 | event->register_event = vmpressure_register_event; | |
5100 | event->unregister_event = vmpressure_unregister_event; | |
5101 | } else if (!strcmp(name, "memory.memsw.usage_in_bytes")) { | |
347c4a87 TH |
5102 | event->register_event = memsw_cgroup_usage_register_event; |
5103 | event->unregister_event = memsw_cgroup_usage_unregister_event; | |
fba94807 TH |
5104 | } else { |
5105 | ret = -EINVAL; | |
5106 | goto out_put_cfile; | |
5107 | } | |
5108 | ||
79bd9814 | 5109 | /* |
b5557c4c TH |
5110 | * Verify @cfile should belong to @css. Also, remaining events are |
5111 | * automatically removed on cgroup destruction but the removal is | |
5112 | * asynchronous, so take an extra ref on @css. | |
79bd9814 | 5113 | */ |
4a7ba45b | 5114 | cfile_css = css_tryget_online_from_dir(cdentry->d_parent, |
ec903c0c | 5115 | &memory_cgrp_subsys); |
79bd9814 | 5116 | ret = -EINVAL; |
5a17f543 | 5117 | if (IS_ERR(cfile_css)) |
79bd9814 | 5118 | goto out_put_cfile; |
5a17f543 TH |
5119 | if (cfile_css != css) { |
5120 | css_put(cfile_css); | |
79bd9814 | 5121 | goto out_put_cfile; |
5a17f543 | 5122 | } |
79bd9814 | 5123 | |
451af504 | 5124 | ret = event->register_event(memcg, event->eventfd, buf); |
79bd9814 TH |
5125 | if (ret) |
5126 | goto out_put_css; | |
5127 | ||
9965ed17 | 5128 | vfs_poll(efile.file, &event->pt); |
79bd9814 | 5129 | |
4ba9515d | 5130 | spin_lock_irq(&memcg->event_list_lock); |
fba94807 | 5131 | list_add(&event->list, &memcg->event_list); |
4ba9515d | 5132 | spin_unlock_irq(&memcg->event_list_lock); |
79bd9814 TH |
5133 | |
5134 | fdput(cfile); | |
5135 | fdput(efile); | |
5136 | ||
451af504 | 5137 | return nbytes; |
79bd9814 TH |
5138 | |
5139 | out_put_css: | |
b5557c4c | 5140 | css_put(css); |
79bd9814 TH |
5141 | out_put_cfile: |
5142 | fdput(cfile); | |
5143 | out_put_eventfd: | |
5144 | eventfd_ctx_put(event->eventfd); | |
5145 | out_put_efile: | |
5146 | fdput(efile); | |
5147 | out_kfree: | |
5148 | kfree(event); | |
5149 | ||
5150 | return ret; | |
5151 | } | |
5152 | ||
c29b5b3d MS |
5153 | #if defined(CONFIG_MEMCG_KMEM) && (defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)) |
5154 | static int mem_cgroup_slab_show(struct seq_file *m, void *p) | |
5155 | { | |
5156 | /* | |
5157 | * Deprecated. | |
df4ae285 | 5158 | * Please, take a look at tools/cgroup/memcg_slabinfo.py . |
c29b5b3d MS |
5159 | */ |
5160 | return 0; | |
5161 | } | |
5162 | #endif | |
5163 | ||
dddb44ff YA |
5164 | static int memory_stat_show(struct seq_file *m, void *v); |
5165 | ||
241994ed | 5166 | static struct cftype mem_cgroup_legacy_files[] = { |
8cdea7c0 | 5167 | { |
0eea1030 | 5168 | .name = "usage_in_bytes", |
8c7c6e34 | 5169 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
791badbd | 5170 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 5171 | }, |
c84872e1 PE |
5172 | { |
5173 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 5174 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
6770c64e | 5175 | .write = mem_cgroup_reset, |
791badbd | 5176 | .read_u64 = mem_cgroup_read_u64, |
c84872e1 | 5177 | }, |
8cdea7c0 | 5178 | { |
0eea1030 | 5179 | .name = "limit_in_bytes", |
8c7c6e34 | 5180 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
451af504 | 5181 | .write = mem_cgroup_write, |
791badbd | 5182 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 5183 | }, |
296c81d8 BS |
5184 | { |
5185 | .name = "soft_limit_in_bytes", | |
5186 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
451af504 | 5187 | .write = mem_cgroup_write, |
791badbd | 5188 | .read_u64 = mem_cgroup_read_u64, |
296c81d8 | 5189 | }, |
8cdea7c0 BS |
5190 | { |
5191 | .name = "failcnt", | |
8c7c6e34 | 5192 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
6770c64e | 5193 | .write = mem_cgroup_reset, |
791badbd | 5194 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 5195 | }, |
d2ceb9b7 KH |
5196 | { |
5197 | .name = "stat", | |
dddb44ff | 5198 | .seq_show = memory_stat_show, |
d2ceb9b7 | 5199 | }, |
c1e862c1 KH |
5200 | { |
5201 | .name = "force_empty", | |
6770c64e | 5202 | .write = mem_cgroup_force_empty_write, |
c1e862c1 | 5203 | }, |
18f59ea7 BS |
5204 | { |
5205 | .name = "use_hierarchy", | |
5206 | .write_u64 = mem_cgroup_hierarchy_write, | |
5207 | .read_u64 = mem_cgroup_hierarchy_read, | |
5208 | }, | |
79bd9814 | 5209 | { |
3bc942f3 | 5210 | .name = "cgroup.event_control", /* XXX: for compat */ |
451af504 | 5211 | .write = memcg_write_event_control, |
7dbdb199 | 5212 | .flags = CFTYPE_NO_PREFIX | CFTYPE_WORLD_WRITABLE, |
79bd9814 | 5213 | }, |
a7885eb8 KM |
5214 | { |
5215 | .name = "swappiness", | |
5216 | .read_u64 = mem_cgroup_swappiness_read, | |
5217 | .write_u64 = mem_cgroup_swappiness_write, | |
5218 | }, | |
7dc74be0 DN |
5219 | { |
5220 | .name = "move_charge_at_immigrate", | |
5221 | .read_u64 = mem_cgroup_move_charge_read, | |
5222 | .write_u64 = mem_cgroup_move_charge_write, | |
5223 | }, | |
9490ff27 KH |
5224 | { |
5225 | .name = "oom_control", | |
2da8ca82 | 5226 | .seq_show = mem_cgroup_oom_control_read, |
3c11ecf4 | 5227 | .write_u64 = mem_cgroup_oom_control_write, |
9490ff27 | 5228 | }, |
70ddf637 AV |
5229 | { |
5230 | .name = "pressure_level", | |
6b0ba2ab | 5231 | .seq_show = mem_cgroup_dummy_seq_show, |
70ddf637 | 5232 | }, |
406eb0c9 YH |
5233 | #ifdef CONFIG_NUMA |
5234 | { | |
5235 | .name = "numa_stat", | |
2da8ca82 | 5236 | .seq_show = memcg_numa_stat_show, |
406eb0c9 YH |
5237 | }, |
5238 | #endif | |
4597648f MH |
5239 | { |
5240 | .name = "kmem.limit_in_bytes", | |
5241 | .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT), | |
5242 | .write = mem_cgroup_write, | |
5243 | .read_u64 = mem_cgroup_read_u64, | |
5244 | }, | |
510fc4e1 GC |
5245 | { |
5246 | .name = "kmem.usage_in_bytes", | |
5247 | .private = MEMFILE_PRIVATE(_KMEM, RES_USAGE), | |
791badbd | 5248 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
5249 | }, |
5250 | { | |
5251 | .name = "kmem.failcnt", | |
5252 | .private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT), | |
6770c64e | 5253 | .write = mem_cgroup_reset, |
791badbd | 5254 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
5255 | }, |
5256 | { | |
5257 | .name = "kmem.max_usage_in_bytes", | |
5258 | .private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE), | |
6770c64e | 5259 | .write = mem_cgroup_reset, |
791badbd | 5260 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 | 5261 | }, |
a87425a3 YS |
5262 | #if defined(CONFIG_MEMCG_KMEM) && \ |
5263 | (defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)) | |
749c5415 GC |
5264 | { |
5265 | .name = "kmem.slabinfo", | |
c29b5b3d | 5266 | .seq_show = mem_cgroup_slab_show, |
749c5415 GC |
5267 | }, |
5268 | #endif | |
d55f90bf VD |
5269 | { |
5270 | .name = "kmem.tcp.limit_in_bytes", | |
5271 | .private = MEMFILE_PRIVATE(_TCP, RES_LIMIT), | |
5272 | .write = mem_cgroup_write, | |
5273 | .read_u64 = mem_cgroup_read_u64, | |
5274 | }, | |
5275 | { | |
5276 | .name = "kmem.tcp.usage_in_bytes", | |
5277 | .private = MEMFILE_PRIVATE(_TCP, RES_USAGE), | |
5278 | .read_u64 = mem_cgroup_read_u64, | |
5279 | }, | |
5280 | { | |
5281 | .name = "kmem.tcp.failcnt", | |
5282 | .private = MEMFILE_PRIVATE(_TCP, RES_FAILCNT), | |
5283 | .write = mem_cgroup_reset, | |
5284 | .read_u64 = mem_cgroup_read_u64, | |
5285 | }, | |
5286 | { | |
5287 | .name = "kmem.tcp.max_usage_in_bytes", | |
5288 | .private = MEMFILE_PRIVATE(_TCP, RES_MAX_USAGE), | |
5289 | .write = mem_cgroup_reset, | |
5290 | .read_u64 = mem_cgroup_read_u64, | |
5291 | }, | |
6bc10349 | 5292 | { }, /* terminate */ |
af36f906 | 5293 | }; |
8c7c6e34 | 5294 | |
73f576c0 JW |
5295 | /* |
5296 | * Private memory cgroup IDR | |
5297 | * | |
5298 | * Swap-out records and page cache shadow entries need to store memcg | |
5299 | * references in constrained space, so we maintain an ID space that is | |
5300 | * limited to 16 bit (MEM_CGROUP_ID_MAX), limiting the total number of | |
5301 | * memory-controlled cgroups to 64k. | |
5302 | * | |
b8f2935f | 5303 | * However, there usually are many references to the offline CSS after |
73f576c0 JW |
5304 | * the cgroup has been destroyed, such as page cache or reclaimable |
5305 | * slab objects, that don't need to hang on to the ID. We want to keep | |
5306 | * those dead CSS from occupying IDs, or we might quickly exhaust the | |
5307 | * relatively small ID space and prevent the creation of new cgroups | |
5308 | * even when there are much fewer than 64k cgroups - possibly none. | |
5309 | * | |
5310 | * Maintain a private 16-bit ID space for memcg, and allow the ID to | |
5311 | * be freed and recycled when it's no longer needed, which is usually | |
5312 | * when the CSS is offlined. | |
5313 | * | |
5314 | * The only exception to that are records of swapped out tmpfs/shmem | |
5315 | * pages that need to be attributed to live ancestors on swapin. But | |
5316 | * those references are manageable from userspace. | |
5317 | */ | |
5318 | ||
60b1e24c | 5319 | #define MEM_CGROUP_ID_MAX ((1UL << MEM_CGROUP_ID_SHIFT) - 1) |
73f576c0 JW |
5320 | static DEFINE_IDR(mem_cgroup_idr); |
5321 | ||
7e97de0b KT |
5322 | static void mem_cgroup_id_remove(struct mem_cgroup *memcg) |
5323 | { | |
5324 | if (memcg->id.id > 0) { | |
5325 | idr_remove(&mem_cgroup_idr, memcg->id.id); | |
5326 | memcg->id.id = 0; | |
5327 | } | |
5328 | } | |
5329 | ||
c1514c0a VF |
5330 | static void __maybe_unused mem_cgroup_id_get_many(struct mem_cgroup *memcg, |
5331 | unsigned int n) | |
73f576c0 | 5332 | { |
1c2d479a | 5333 | refcount_add(n, &memcg->id.ref); |
73f576c0 JW |
5334 | } |
5335 | ||
615d66c3 | 5336 | static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n) |
73f576c0 | 5337 | { |
1c2d479a | 5338 | if (refcount_sub_and_test(n, &memcg->id.ref)) { |
7e97de0b | 5339 | mem_cgroup_id_remove(memcg); |
73f576c0 JW |
5340 | |
5341 | /* Memcg ID pins CSS */ | |
5342 | css_put(&memcg->css); | |
5343 | } | |
5344 | } | |
5345 | ||
615d66c3 VD |
5346 | static inline void mem_cgroup_id_put(struct mem_cgroup *memcg) |
5347 | { | |
5348 | mem_cgroup_id_put_many(memcg, 1); | |
5349 | } | |
5350 | ||
73f576c0 JW |
5351 | /** |
5352 | * mem_cgroup_from_id - look up a memcg from a memcg id | |
5353 | * @id: the memcg id to look up | |
5354 | * | |
5355 | * Caller must hold rcu_read_lock(). | |
5356 | */ | |
5357 | struct mem_cgroup *mem_cgroup_from_id(unsigned short id) | |
5358 | { | |
5359 | WARN_ON_ONCE(!rcu_read_lock_held()); | |
5360 | return idr_find(&mem_cgroup_idr, id); | |
5361 | } | |
5362 | ||
c15187a4 RG |
5363 | #ifdef CONFIG_SHRINKER_DEBUG |
5364 | struct mem_cgroup *mem_cgroup_get_from_ino(unsigned long ino) | |
5365 | { | |
5366 | struct cgroup *cgrp; | |
5367 | struct cgroup_subsys_state *css; | |
5368 | struct mem_cgroup *memcg; | |
5369 | ||
5370 | cgrp = cgroup_get_from_id(ino); | |
fa7e439c | 5371 | if (IS_ERR(cgrp)) |
c0f2df49 | 5372 | return ERR_CAST(cgrp); |
c15187a4 RG |
5373 | |
5374 | css = cgroup_get_e_css(cgrp, &memory_cgrp_subsys); | |
5375 | if (css) | |
5376 | memcg = container_of(css, struct mem_cgroup, css); | |
5377 | else | |
5378 | memcg = ERR_PTR(-ENOENT); | |
5379 | ||
5380 | cgroup_put(cgrp); | |
5381 | ||
5382 | return memcg; | |
5383 | } | |
5384 | #endif | |
5385 | ||
ef8f2327 | 5386 | static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) |
6d12e2d8 KH |
5387 | { |
5388 | struct mem_cgroup_per_node *pn; | |
8c9bb398 WY |
5389 | |
5390 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, node); | |
6d12e2d8 KH |
5391 | if (!pn) |
5392 | return 1; | |
1ecaab2b | 5393 | |
7e1c0d6f SB |
5394 | pn->lruvec_stats_percpu = alloc_percpu_gfp(struct lruvec_stats_percpu, |
5395 | GFP_KERNEL_ACCOUNT); | |
5396 | if (!pn->lruvec_stats_percpu) { | |
00f3ca2c JW |
5397 | kfree(pn); |
5398 | return 1; | |
5399 | } | |
5400 | ||
ef8f2327 | 5401 | lruvec_init(&pn->lruvec); |
ef8f2327 MG |
5402 | pn->memcg = memcg; |
5403 | ||
54f72fe0 | 5404 | memcg->nodeinfo[node] = pn; |
6d12e2d8 KH |
5405 | return 0; |
5406 | } | |
5407 | ||
ef8f2327 | 5408 | static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) |
1ecaab2b | 5409 | { |
00f3ca2c JW |
5410 | struct mem_cgroup_per_node *pn = memcg->nodeinfo[node]; |
5411 | ||
4eaf431f MH |
5412 | if (!pn) |
5413 | return; | |
5414 | ||
7e1c0d6f | 5415 | free_percpu(pn->lruvec_stats_percpu); |
00f3ca2c | 5416 | kfree(pn); |
1ecaab2b KH |
5417 | } |
5418 | ||
40e952f9 | 5419 | static void __mem_cgroup_free(struct mem_cgroup *memcg) |
59927fb9 | 5420 | { |
c8b2a36f | 5421 | int node; |
59927fb9 | 5422 | |
675d6c9b RG |
5423 | if (memcg->orig_objcg) |
5424 | obj_cgroup_put(memcg->orig_objcg); | |
5425 | ||
c8b2a36f | 5426 | for_each_node(node) |
ef8f2327 | 5427 | free_mem_cgroup_per_node_info(memcg, node); |
410f8e82 | 5428 | kfree(memcg->vmstats); |
871789d4 | 5429 | free_percpu(memcg->vmstats_percpu); |
8ff69e2c | 5430 | kfree(memcg); |
59927fb9 | 5431 | } |
3afe36b1 | 5432 | |
40e952f9 TE |
5433 | static void mem_cgroup_free(struct mem_cgroup *memcg) |
5434 | { | |
ec1c86b2 | 5435 | lru_gen_exit_memcg(memcg); |
40e952f9 TE |
5436 | memcg_wb_domain_exit(memcg); |
5437 | __mem_cgroup_free(memcg); | |
5438 | } | |
5439 | ||
0b8f73e1 | 5440 | static struct mem_cgroup *mem_cgroup_alloc(void) |
8cdea7c0 | 5441 | { |
d142e3e6 | 5442 | struct mem_cgroup *memcg; |
6d12e2d8 | 5443 | int node; |
97b27821 | 5444 | int __maybe_unused i; |
11d67612 | 5445 | long error = -ENOMEM; |
8cdea7c0 | 5446 | |
06b2c3b0 | 5447 | memcg = kzalloc(struct_size(memcg, nodeinfo, nr_node_ids), GFP_KERNEL); |
c0ff4b85 | 5448 | if (!memcg) |
11d67612 | 5449 | return ERR_PTR(error); |
0b8f73e1 | 5450 | |
73f576c0 | 5451 | memcg->id.id = idr_alloc(&mem_cgroup_idr, NULL, |
be740503 | 5452 | 1, MEM_CGROUP_ID_MAX + 1, GFP_KERNEL); |
11d67612 YS |
5453 | if (memcg->id.id < 0) { |
5454 | error = memcg->id.id; | |
73f576c0 | 5455 | goto fail; |
11d67612 | 5456 | } |
73f576c0 | 5457 | |
410f8e82 SB |
5458 | memcg->vmstats = kzalloc(sizeof(struct memcg_vmstats), GFP_KERNEL); |
5459 | if (!memcg->vmstats) | |
5460 | goto fail; | |
5461 | ||
3e38e0aa RG |
5462 | memcg->vmstats_percpu = alloc_percpu_gfp(struct memcg_vmstats_percpu, |
5463 | GFP_KERNEL_ACCOUNT); | |
871789d4 | 5464 | if (!memcg->vmstats_percpu) |
0b8f73e1 | 5465 | goto fail; |
78fb7466 | 5466 | |
3ed28fa1 | 5467 | for_each_node(node) |
ef8f2327 | 5468 | if (alloc_mem_cgroup_per_node_info(memcg, node)) |
0b8f73e1 | 5469 | goto fail; |
f64c3f54 | 5470 | |
0b8f73e1 JW |
5471 | if (memcg_wb_domain_init(memcg, GFP_KERNEL)) |
5472 | goto fail; | |
28dbc4b6 | 5473 | |
f7e1cb6e | 5474 | INIT_WORK(&memcg->high_work, high_work_func); |
d142e3e6 | 5475 | INIT_LIST_HEAD(&memcg->oom_notify); |
d142e3e6 GC |
5476 | mutex_init(&memcg->thresholds_lock); |
5477 | spin_lock_init(&memcg->move_lock); | |
70ddf637 | 5478 | vmpressure_init(&memcg->vmpressure); |
fba94807 TH |
5479 | INIT_LIST_HEAD(&memcg->event_list); |
5480 | spin_lock_init(&memcg->event_list_lock); | |
d886f4e4 | 5481 | memcg->socket_pressure = jiffies; |
84c07d11 | 5482 | #ifdef CONFIG_MEMCG_KMEM |
900a38f0 | 5483 | memcg->kmemcg_id = -1; |
bf4f0599 | 5484 | INIT_LIST_HEAD(&memcg->objcg_list); |
900a38f0 | 5485 | #endif |
52ebea74 TH |
5486 | #ifdef CONFIG_CGROUP_WRITEBACK |
5487 | INIT_LIST_HEAD(&memcg->cgwb_list); | |
97b27821 TH |
5488 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) |
5489 | memcg->cgwb_frn[i].done = | |
5490 | __WB_COMPLETION_INIT(&memcg_cgwb_frn_waitq); | |
87eaceb3 YS |
5491 | #endif |
5492 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
5493 | spin_lock_init(&memcg->deferred_split_queue.split_queue_lock); | |
5494 | INIT_LIST_HEAD(&memcg->deferred_split_queue.split_queue); | |
5495 | memcg->deferred_split_queue.split_queue_len = 0; | |
52ebea74 | 5496 | #endif |
ec1c86b2 | 5497 | lru_gen_init_memcg(memcg); |
0b8f73e1 JW |
5498 | return memcg; |
5499 | fail: | |
7e97de0b | 5500 | mem_cgroup_id_remove(memcg); |
40e952f9 | 5501 | __mem_cgroup_free(memcg); |
11d67612 | 5502 | return ERR_PTR(error); |
d142e3e6 GC |
5503 | } |
5504 | ||
0b8f73e1 JW |
5505 | static struct cgroup_subsys_state * __ref |
5506 | mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
d142e3e6 | 5507 | { |
0b8f73e1 | 5508 | struct mem_cgroup *parent = mem_cgroup_from_css(parent_css); |
b87d8cef | 5509 | struct mem_cgroup *memcg, *old_memcg; |
d142e3e6 | 5510 | |
b87d8cef | 5511 | old_memcg = set_active_memcg(parent); |
0b8f73e1 | 5512 | memcg = mem_cgroup_alloc(); |
b87d8cef | 5513 | set_active_memcg(old_memcg); |
11d67612 YS |
5514 | if (IS_ERR(memcg)) |
5515 | return ERR_CAST(memcg); | |
d142e3e6 | 5516 | |
d1663a90 | 5517 | page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX); |
2178e20c | 5518 | WRITE_ONCE(memcg->soft_limit, PAGE_COUNTER_MAX); |
f4840ccf JW |
5519 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
5520 | memcg->zswap_max = PAGE_COUNTER_MAX; | |
5521 | #endif | |
4b82ab4f | 5522 | page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX); |
0b8f73e1 | 5523 | if (parent) { |
82b3aa26 | 5524 | WRITE_ONCE(memcg->swappiness, mem_cgroup_swappiness(parent)); |
17c56de6 | 5525 | WRITE_ONCE(memcg->oom_kill_disable, READ_ONCE(parent->oom_kill_disable)); |
bef8620c | 5526 | |
3e32cb2e | 5527 | page_counter_init(&memcg->memory, &parent->memory); |
37e84351 | 5528 | page_counter_init(&memcg->swap, &parent->swap); |
3e32cb2e | 5529 | page_counter_init(&memcg->kmem, &parent->kmem); |
0db15298 | 5530 | page_counter_init(&memcg->tcpmem, &parent->tcpmem); |
18f59ea7 | 5531 | } else { |
8278f1c7 | 5532 | init_memcg_events(); |
bef8620c RG |
5533 | page_counter_init(&memcg->memory, NULL); |
5534 | page_counter_init(&memcg->swap, NULL); | |
5535 | page_counter_init(&memcg->kmem, NULL); | |
5536 | page_counter_init(&memcg->tcpmem, NULL); | |
d6441637 | 5537 | |
0b8f73e1 JW |
5538 | root_mem_cgroup = memcg; |
5539 | return &memcg->css; | |
5540 | } | |
5541 | ||
f7e1cb6e | 5542 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 5543 | static_branch_inc(&memcg_sockets_enabled_key); |
f7e1cb6e | 5544 | |
b6c1a8af YS |
5545 | #if defined(CONFIG_MEMCG_KMEM) |
5546 | if (!cgroup_memory_nobpf) | |
5547 | static_branch_inc(&memcg_bpf_enabled_key); | |
5548 | #endif | |
5549 | ||
0b8f73e1 | 5550 | return &memcg->css; |
0b8f73e1 JW |
5551 | } |
5552 | ||
73f576c0 | 5553 | static int mem_cgroup_css_online(struct cgroup_subsys_state *css) |
0b8f73e1 | 5554 | { |
58fa2a55 VD |
5555 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
5556 | ||
da0efe30 MS |
5557 | if (memcg_online_kmem(memcg)) |
5558 | goto remove_id; | |
5559 | ||
0a4465d3 | 5560 | /* |
e4262c4f | 5561 | * A memcg must be visible for expand_shrinker_info() |
0a4465d3 KT |
5562 | * by the time the maps are allocated. So, we allocate maps |
5563 | * here, when for_each_mem_cgroup() can't skip it. | |
5564 | */ | |
da0efe30 MS |
5565 | if (alloc_shrinker_info(memcg)) |
5566 | goto offline_kmem; | |
0a4465d3 | 5567 | |
aa48e47e SB |
5568 | if (unlikely(mem_cgroup_is_root(memcg))) |
5569 | queue_delayed_work(system_unbound_wq, &stats_flush_dwork, | |
396faf88 | 5570 | FLUSH_TIME); |
e4dde56c | 5571 | lru_gen_online_memcg(memcg); |
6f0df8e1 JW |
5572 | |
5573 | /* Online state pins memcg ID, memcg ID pins CSS */ | |
5574 | refcount_set(&memcg->id.ref, 1); | |
5575 | css_get(css); | |
5576 | ||
5577 | /* | |
5578 | * Ensure mem_cgroup_from_id() works once we're fully online. | |
5579 | * | |
5580 | * We could do this earlier and require callers to filter with | |
5581 | * css_tryget_online(). But right now there are no users that | |
5582 | * need earlier access, and the workingset code relies on the | |
5583 | * cgroup tree linkage (mem_cgroup_get_nr_swap_pages()). So | |
5584 | * publish it here at the end of onlining. This matches the | |
5585 | * regular ID destruction during offlining. | |
5586 | */ | |
5587 | idr_replace(&mem_cgroup_idr, memcg, memcg->id.id); | |
5588 | ||
2f7dd7a4 | 5589 | return 0; |
da0efe30 MS |
5590 | offline_kmem: |
5591 | memcg_offline_kmem(memcg); | |
5592 | remove_id: | |
5593 | mem_cgroup_id_remove(memcg); | |
5594 | return -ENOMEM; | |
8cdea7c0 BS |
5595 | } |
5596 | ||
eb95419b | 5597 | static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) |
df878fb0 | 5598 | { |
eb95419b | 5599 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 5600 | struct mem_cgroup_event *event, *tmp; |
79bd9814 TH |
5601 | |
5602 | /* | |
5603 | * Unregister events and notify userspace. | |
5604 | * Notify userspace about cgroup removing only after rmdir of cgroup | |
5605 | * directory to avoid race between userspace and kernelspace. | |
5606 | */ | |
4ba9515d | 5607 | spin_lock_irq(&memcg->event_list_lock); |
fba94807 | 5608 | list_for_each_entry_safe(event, tmp, &memcg->event_list, list) { |
79bd9814 TH |
5609 | list_del_init(&event->list); |
5610 | schedule_work(&event->remove); | |
5611 | } | |
4ba9515d | 5612 | spin_unlock_irq(&memcg->event_list_lock); |
ec64f515 | 5613 | |
bf8d5d52 | 5614 | page_counter_set_min(&memcg->memory, 0); |
23067153 | 5615 | page_counter_set_low(&memcg->memory, 0); |
63677c74 | 5616 | |
567e9ab2 | 5617 | memcg_offline_kmem(memcg); |
a178015c | 5618 | reparent_shrinker_deferred(memcg); |
52ebea74 | 5619 | wb_memcg_offline(memcg); |
e4dde56c | 5620 | lru_gen_offline_memcg(memcg); |
73f576c0 | 5621 | |
591edfb1 RG |
5622 | drain_all_stock(memcg); |
5623 | ||
73f576c0 | 5624 | mem_cgroup_id_put(memcg); |
df878fb0 KH |
5625 | } |
5626 | ||
6df38689 VD |
5627 | static void mem_cgroup_css_released(struct cgroup_subsys_state *css) |
5628 | { | |
5629 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5630 | ||
5631 | invalidate_reclaim_iterators(memcg); | |
e4dde56c | 5632 | lru_gen_release_memcg(memcg); |
6df38689 VD |
5633 | } |
5634 | ||
eb95419b | 5635 | static void mem_cgroup_css_free(struct cgroup_subsys_state *css) |
8cdea7c0 | 5636 | { |
eb95419b | 5637 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
97b27821 | 5638 | int __maybe_unused i; |
c268e994 | 5639 | |
97b27821 TH |
5640 | #ifdef CONFIG_CGROUP_WRITEBACK |
5641 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) | |
5642 | wb_wait_for_completion(&memcg->cgwb_frn[i].done); | |
5643 | #endif | |
f7e1cb6e | 5644 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 5645 | static_branch_dec(&memcg_sockets_enabled_key); |
127424c8 | 5646 | |
0db15298 | 5647 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_active) |
d55f90bf | 5648 | static_branch_dec(&memcg_sockets_enabled_key); |
3893e302 | 5649 | |
b6c1a8af YS |
5650 | #if defined(CONFIG_MEMCG_KMEM) |
5651 | if (!cgroup_memory_nobpf) | |
5652 | static_branch_dec(&memcg_bpf_enabled_key); | |
5653 | #endif | |
5654 | ||
0b8f73e1 JW |
5655 | vmpressure_cleanup(&memcg->vmpressure); |
5656 | cancel_work_sync(&memcg->high_work); | |
5657 | mem_cgroup_remove_from_trees(memcg); | |
e4262c4f | 5658 | free_shrinker_info(memcg); |
0b8f73e1 | 5659 | mem_cgroup_free(memcg); |
8cdea7c0 BS |
5660 | } |
5661 | ||
1ced953b TH |
5662 | /** |
5663 | * mem_cgroup_css_reset - reset the states of a mem_cgroup | |
5664 | * @css: the target css | |
5665 | * | |
5666 | * Reset the states of the mem_cgroup associated with @css. This is | |
5667 | * invoked when the userland requests disabling on the default hierarchy | |
5668 | * but the memcg is pinned through dependency. The memcg should stop | |
5669 | * applying policies and should revert to the vanilla state as it may be | |
5670 | * made visible again. | |
5671 | * | |
5672 | * The current implementation only resets the essential configurations. | |
5673 | * This needs to be expanded to cover all the visible parts. | |
5674 | */ | |
5675 | static void mem_cgroup_css_reset(struct cgroup_subsys_state *css) | |
5676 | { | |
5677 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5678 | ||
bbec2e15 RG |
5679 | page_counter_set_max(&memcg->memory, PAGE_COUNTER_MAX); |
5680 | page_counter_set_max(&memcg->swap, PAGE_COUNTER_MAX); | |
bbec2e15 RG |
5681 | page_counter_set_max(&memcg->kmem, PAGE_COUNTER_MAX); |
5682 | page_counter_set_max(&memcg->tcpmem, PAGE_COUNTER_MAX); | |
bf8d5d52 | 5683 | page_counter_set_min(&memcg->memory, 0); |
23067153 | 5684 | page_counter_set_low(&memcg->memory, 0); |
d1663a90 | 5685 | page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX); |
2178e20c | 5686 | WRITE_ONCE(memcg->soft_limit, PAGE_COUNTER_MAX); |
4b82ab4f | 5687 | page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX); |
2529bb3a | 5688 | memcg_wb_domain_size_changed(memcg); |
1ced953b TH |
5689 | } |
5690 | ||
2d146aa3 JW |
5691 | static void mem_cgroup_css_rstat_flush(struct cgroup_subsys_state *css, int cpu) |
5692 | { | |
5693 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5694 | struct mem_cgroup *parent = parent_mem_cgroup(memcg); | |
5695 | struct memcg_vmstats_percpu *statc; | |
f82e6bf9 | 5696 | long delta, delta_cpu, v; |
7e1c0d6f | 5697 | int i, nid; |
2d146aa3 JW |
5698 | |
5699 | statc = per_cpu_ptr(memcg->vmstats_percpu, cpu); | |
5700 | ||
5701 | for (i = 0; i < MEMCG_NR_STAT; i++) { | |
5702 | /* | |
5703 | * Collect the aggregated propagation counts of groups | |
5704 | * below us. We're in a per-cpu loop here and this is | |
5705 | * a global counter, so the first cycle will get them. | |
5706 | */ | |
410f8e82 | 5707 | delta = memcg->vmstats->state_pending[i]; |
2d146aa3 | 5708 | if (delta) |
410f8e82 | 5709 | memcg->vmstats->state_pending[i] = 0; |
2d146aa3 JW |
5710 | |
5711 | /* Add CPU changes on this level since the last flush */ | |
f82e6bf9 | 5712 | delta_cpu = 0; |
2d146aa3 JW |
5713 | v = READ_ONCE(statc->state[i]); |
5714 | if (v != statc->state_prev[i]) { | |
f82e6bf9 YA |
5715 | delta_cpu = v - statc->state_prev[i]; |
5716 | delta += delta_cpu; | |
2d146aa3 JW |
5717 | statc->state_prev[i] = v; |
5718 | } | |
5719 | ||
2d146aa3 | 5720 | /* Aggregate counts on this level and propagate upwards */ |
f82e6bf9 YA |
5721 | if (delta_cpu) |
5722 | memcg->vmstats->state_local[i] += delta_cpu; | |
5723 | ||
5724 | if (delta) { | |
5725 | memcg->vmstats->state[i] += delta; | |
5726 | if (parent) | |
5727 | parent->vmstats->state_pending[i] += delta; | |
5728 | } | |
2d146aa3 JW |
5729 | } |
5730 | ||
8278f1c7 | 5731 | for (i = 0; i < NR_MEMCG_EVENTS; i++) { |
410f8e82 | 5732 | delta = memcg->vmstats->events_pending[i]; |
2d146aa3 | 5733 | if (delta) |
410f8e82 | 5734 | memcg->vmstats->events_pending[i] = 0; |
2d146aa3 | 5735 | |
f82e6bf9 | 5736 | delta_cpu = 0; |
2d146aa3 JW |
5737 | v = READ_ONCE(statc->events[i]); |
5738 | if (v != statc->events_prev[i]) { | |
f82e6bf9 YA |
5739 | delta_cpu = v - statc->events_prev[i]; |
5740 | delta += delta_cpu; | |
2d146aa3 JW |
5741 | statc->events_prev[i] = v; |
5742 | } | |
5743 | ||
f82e6bf9 YA |
5744 | if (delta_cpu) |
5745 | memcg->vmstats->events_local[i] += delta_cpu; | |
2d146aa3 | 5746 | |
f82e6bf9 YA |
5747 | if (delta) { |
5748 | memcg->vmstats->events[i] += delta; | |
5749 | if (parent) | |
5750 | parent->vmstats->events_pending[i] += delta; | |
5751 | } | |
2d146aa3 | 5752 | } |
7e1c0d6f SB |
5753 | |
5754 | for_each_node_state(nid, N_MEMORY) { | |
5755 | struct mem_cgroup_per_node *pn = memcg->nodeinfo[nid]; | |
5756 | struct mem_cgroup_per_node *ppn = NULL; | |
5757 | struct lruvec_stats_percpu *lstatc; | |
5758 | ||
5759 | if (parent) | |
5760 | ppn = parent->nodeinfo[nid]; | |
5761 | ||
5762 | lstatc = per_cpu_ptr(pn->lruvec_stats_percpu, cpu); | |
5763 | ||
5764 | for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { | |
5765 | delta = pn->lruvec_stats.state_pending[i]; | |
5766 | if (delta) | |
5767 | pn->lruvec_stats.state_pending[i] = 0; | |
5768 | ||
f82e6bf9 | 5769 | delta_cpu = 0; |
7e1c0d6f SB |
5770 | v = READ_ONCE(lstatc->state[i]); |
5771 | if (v != lstatc->state_prev[i]) { | |
f82e6bf9 YA |
5772 | delta_cpu = v - lstatc->state_prev[i]; |
5773 | delta += delta_cpu; | |
7e1c0d6f SB |
5774 | lstatc->state_prev[i] = v; |
5775 | } | |
5776 | ||
f82e6bf9 YA |
5777 | if (delta_cpu) |
5778 | pn->lruvec_stats.state_local[i] += delta_cpu; | |
7e1c0d6f | 5779 | |
f82e6bf9 YA |
5780 | if (delta) { |
5781 | pn->lruvec_stats.state[i] += delta; | |
5782 | if (ppn) | |
5783 | ppn->lruvec_stats.state_pending[i] += delta; | |
5784 | } | |
7e1c0d6f SB |
5785 | } |
5786 | } | |
2d146aa3 JW |
5787 | } |
5788 | ||
02491447 | 5789 | #ifdef CONFIG_MMU |
7dc74be0 | 5790 | /* Handlers for move charge at task migration. */ |
854ffa8d | 5791 | static int mem_cgroup_do_precharge(unsigned long count) |
7dc74be0 | 5792 | { |
05b84301 | 5793 | int ret; |
9476db97 | 5794 | |
d0164adc MG |
5795 | /* Try a single bulk charge without reclaim first, kswapd may wake */ |
5796 | ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_DIRECT_RECLAIM, count); | |
9476db97 | 5797 | if (!ret) { |
854ffa8d | 5798 | mc.precharge += count; |
854ffa8d DN |
5799 | return ret; |
5800 | } | |
9476db97 | 5801 | |
3674534b | 5802 | /* Try charges one by one with reclaim, but do not retry */ |
854ffa8d | 5803 | while (count--) { |
3674534b | 5804 | ret = try_charge(mc.to, GFP_KERNEL | __GFP_NORETRY, 1); |
38c5d72f | 5805 | if (ret) |
38c5d72f | 5806 | return ret; |
854ffa8d | 5807 | mc.precharge++; |
9476db97 | 5808 | cond_resched(); |
854ffa8d | 5809 | } |
9476db97 | 5810 | return 0; |
4ffef5fe DN |
5811 | } |
5812 | ||
4ffef5fe DN |
5813 | union mc_target { |
5814 | struct page *page; | |
02491447 | 5815 | swp_entry_t ent; |
4ffef5fe DN |
5816 | }; |
5817 | ||
4ffef5fe | 5818 | enum mc_target_type { |
8d32ff84 | 5819 | MC_TARGET_NONE = 0, |
4ffef5fe | 5820 | MC_TARGET_PAGE, |
02491447 | 5821 | MC_TARGET_SWAP, |
c733a828 | 5822 | MC_TARGET_DEVICE, |
4ffef5fe DN |
5823 | }; |
5824 | ||
90254a65 DN |
5825 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
5826 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 5827 | { |
25b2995a | 5828 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 5829 | |
58f341f7 | 5830 | if (!page) |
90254a65 DN |
5831 | return NULL; |
5832 | if (PageAnon(page)) { | |
1dfab5ab | 5833 | if (!(mc.flags & MOVE_ANON)) |
90254a65 | 5834 | return NULL; |
1dfab5ab JW |
5835 | } else { |
5836 | if (!(mc.flags & MOVE_FILE)) | |
5837 | return NULL; | |
5838 | } | |
58f341f7 | 5839 | get_page(page); |
90254a65 DN |
5840 | |
5841 | return page; | |
5842 | } | |
5843 | ||
c733a828 | 5844 | #if defined(CONFIG_SWAP) || defined(CONFIG_DEVICE_PRIVATE) |
90254a65 | 5845 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, |
48406ef8 | 5846 | pte_t ptent, swp_entry_t *entry) |
90254a65 | 5847 | { |
90254a65 DN |
5848 | struct page *page = NULL; |
5849 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
5850 | ||
9a137153 | 5851 | if (!(mc.flags & MOVE_ANON)) |
90254a65 | 5852 | return NULL; |
c733a828 JG |
5853 | |
5854 | /* | |
27674ef6 CH |
5855 | * Handle device private pages that are not accessible by the CPU, but |
5856 | * stored as special swap entries in the page table. | |
c733a828 JG |
5857 | */ |
5858 | if (is_device_private_entry(ent)) { | |
af5cdaf8 | 5859 | page = pfn_swap_entry_to_page(ent); |
27674ef6 | 5860 | if (!get_page_unless_zero(page)) |
c733a828 JG |
5861 | return NULL; |
5862 | return page; | |
5863 | } | |
5864 | ||
9a137153 RC |
5865 | if (non_swap_entry(ent)) |
5866 | return NULL; | |
5867 | ||
4b91355e | 5868 | /* |
cb691e2f | 5869 | * Because swap_cache_get_folio() updates some statistics counter, |
4b91355e KH |
5870 | * we call find_get_page() with swapper_space directly. |
5871 | */ | |
f6ab1f7f | 5872 | page = find_get_page(swap_address_space(ent), swp_offset(ent)); |
2d1c4980 | 5873 | entry->val = ent.val; |
90254a65 DN |
5874 | |
5875 | return page; | |
5876 | } | |
4b91355e KH |
5877 | #else |
5878 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
48406ef8 | 5879 | pte_t ptent, swp_entry_t *entry) |
4b91355e KH |
5880 | { |
5881 | return NULL; | |
5882 | } | |
5883 | #endif | |
90254a65 | 5884 | |
87946a72 | 5885 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
48384b0b | 5886 | unsigned long addr, pte_t ptent) |
87946a72 | 5887 | { |
524984ff MWO |
5888 | unsigned long index; |
5889 | struct folio *folio; | |
5890 | ||
87946a72 DN |
5891 | if (!vma->vm_file) /* anonymous vma */ |
5892 | return NULL; | |
1dfab5ab | 5893 | if (!(mc.flags & MOVE_FILE)) |
87946a72 DN |
5894 | return NULL; |
5895 | ||
524984ff | 5896 | /* folio is moved even if it's not RSS of this task(page-faulted). */ |
aa3b1895 | 5897 | /* shmem/tmpfs may report page out on swap: account for that too. */ |
524984ff MWO |
5898 | index = linear_page_index(vma, addr); |
5899 | folio = filemap_get_incore_folio(vma->vm_file->f_mapping, index); | |
66dabbb6 | 5900 | if (IS_ERR(folio)) |
524984ff MWO |
5901 | return NULL; |
5902 | return folio_file_page(folio, index); | |
87946a72 DN |
5903 | } |
5904 | ||
b1b0deab CG |
5905 | /** |
5906 | * mem_cgroup_move_account - move account of the page | |
5907 | * @page: the page | |
25843c2b | 5908 | * @compound: charge the page as compound or small page |
b1b0deab CG |
5909 | * @from: mem_cgroup which the page is moved from. |
5910 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
5911 | * | |
4e0cf05f | 5912 | * The page must be locked and not on the LRU. |
b1b0deab CG |
5913 | * |
5914 | * This function doesn't do "charge" to new cgroup and doesn't do "uncharge" | |
5915 | * from old cgroup. | |
5916 | */ | |
5917 | static int mem_cgroup_move_account(struct page *page, | |
f627c2f5 | 5918 | bool compound, |
b1b0deab CG |
5919 | struct mem_cgroup *from, |
5920 | struct mem_cgroup *to) | |
5921 | { | |
fcce4672 | 5922 | struct folio *folio = page_folio(page); |
ae8af438 KK |
5923 | struct lruvec *from_vec, *to_vec; |
5924 | struct pglist_data *pgdat; | |
fcce4672 | 5925 | unsigned int nr_pages = compound ? folio_nr_pages(folio) : 1; |
8e88bd2d | 5926 | int nid, ret; |
b1b0deab CG |
5927 | |
5928 | VM_BUG_ON(from == to); | |
4e0cf05f | 5929 | VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); |
fcce4672 | 5930 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
9c325215 | 5931 | VM_BUG_ON(compound && !folio_test_large(folio)); |
b1b0deab | 5932 | |
b1b0deab | 5933 | ret = -EINVAL; |
fcce4672 | 5934 | if (folio_memcg(folio) != from) |
4e0cf05f | 5935 | goto out; |
b1b0deab | 5936 | |
fcce4672 | 5937 | pgdat = folio_pgdat(folio); |
867e5e1d JW |
5938 | from_vec = mem_cgroup_lruvec(from, pgdat); |
5939 | to_vec = mem_cgroup_lruvec(to, pgdat); | |
ae8af438 | 5940 | |
fcce4672 | 5941 | folio_memcg_lock(folio); |
b1b0deab | 5942 | |
fcce4672 MWO |
5943 | if (folio_test_anon(folio)) { |
5944 | if (folio_mapped(folio)) { | |
be5d0a74 JW |
5945 | __mod_lruvec_state(from_vec, NR_ANON_MAPPED, -nr_pages); |
5946 | __mod_lruvec_state(to_vec, NR_ANON_MAPPED, nr_pages); | |
6199277b | 5947 | if (folio_test_pmd_mappable(folio)) { |
69473e5d MS |
5948 | __mod_lruvec_state(from_vec, NR_ANON_THPS, |
5949 | -nr_pages); | |
5950 | __mod_lruvec_state(to_vec, NR_ANON_THPS, | |
5951 | nr_pages); | |
468c3982 | 5952 | } |
be5d0a74 JW |
5953 | } |
5954 | } else { | |
0d1c2072 JW |
5955 | __mod_lruvec_state(from_vec, NR_FILE_PAGES, -nr_pages); |
5956 | __mod_lruvec_state(to_vec, NR_FILE_PAGES, nr_pages); | |
5957 | ||
fcce4672 | 5958 | if (folio_test_swapbacked(folio)) { |
0d1c2072 JW |
5959 | __mod_lruvec_state(from_vec, NR_SHMEM, -nr_pages); |
5960 | __mod_lruvec_state(to_vec, NR_SHMEM, nr_pages); | |
5961 | } | |
5962 | ||
fcce4672 | 5963 | if (folio_mapped(folio)) { |
49e50d27 JW |
5964 | __mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages); |
5965 | __mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages); | |
5966 | } | |
b1b0deab | 5967 | |
fcce4672 MWO |
5968 | if (folio_test_dirty(folio)) { |
5969 | struct address_space *mapping = folio_mapping(folio); | |
c4843a75 | 5970 | |
f56753ac | 5971 | if (mapping_can_writeback(mapping)) { |
49e50d27 JW |
5972 | __mod_lruvec_state(from_vec, NR_FILE_DIRTY, |
5973 | -nr_pages); | |
5974 | __mod_lruvec_state(to_vec, NR_FILE_DIRTY, | |
5975 | nr_pages); | |
5976 | } | |
c4843a75 GT |
5977 | } |
5978 | } | |
5979 | ||
c449deb2 HD |
5980 | #ifdef CONFIG_SWAP |
5981 | if (folio_test_swapcache(folio)) { | |
5982 | __mod_lruvec_state(from_vec, NR_SWAPCACHE, -nr_pages); | |
5983 | __mod_lruvec_state(to_vec, NR_SWAPCACHE, nr_pages); | |
5984 | } | |
5985 | #endif | |
fcce4672 | 5986 | if (folio_test_writeback(folio)) { |
ae8af438 KK |
5987 | __mod_lruvec_state(from_vec, NR_WRITEBACK, -nr_pages); |
5988 | __mod_lruvec_state(to_vec, NR_WRITEBACK, nr_pages); | |
b1b0deab CG |
5989 | } |
5990 | ||
5991 | /* | |
abb242f5 JW |
5992 | * All state has been migrated, let's switch to the new memcg. |
5993 | * | |
bcfe06bf | 5994 | * It is safe to change page's memcg here because the page |
abb242f5 JW |
5995 | * is referenced, charged, isolated, and locked: we can't race |
5996 | * with (un)charging, migration, LRU putback, or anything else | |
bcfe06bf | 5997 | * that would rely on a stable page's memory cgroup. |
abb242f5 | 5998 | * |
6c77b607 | 5999 | * Note that folio_memcg_lock is a memcg lock, not a page lock, |
bcfe06bf | 6000 | * to save space. As soon as we switch page's memory cgroup to a |
abb242f5 JW |
6001 | * new memcg that isn't locked, the above state can change |
6002 | * concurrently again. Make sure we're truly done with it. | |
b1b0deab | 6003 | */ |
abb242f5 | 6004 | smp_mb(); |
b1b0deab | 6005 | |
1a3e1f40 JW |
6006 | css_get(&to->css); |
6007 | css_put(&from->css); | |
6008 | ||
fcce4672 | 6009 | folio->memcg_data = (unsigned long)to; |
87eaceb3 | 6010 | |
f70ad448 | 6011 | __folio_memcg_unlock(from); |
b1b0deab CG |
6012 | |
6013 | ret = 0; | |
fcce4672 | 6014 | nid = folio_nid(folio); |
b1b0deab CG |
6015 | |
6016 | local_irq_disable(); | |
6e0110c2 | 6017 | mem_cgroup_charge_statistics(to, nr_pages); |
8e88bd2d | 6018 | memcg_check_events(to, nid); |
6e0110c2 | 6019 | mem_cgroup_charge_statistics(from, -nr_pages); |
8e88bd2d | 6020 | memcg_check_events(from, nid); |
b1b0deab | 6021 | local_irq_enable(); |
b1b0deab CG |
6022 | out: |
6023 | return ret; | |
6024 | } | |
6025 | ||
7cf7806c LR |
6026 | /** |
6027 | * get_mctgt_type - get target type of moving charge | |
6028 | * @vma: the vma the pte to be checked belongs | |
6029 | * @addr: the address corresponding to the pte to be checked | |
6030 | * @ptent: the pte to be checked | |
6031 | * @target: the pointer the target page or swap ent will be stored(can be NULL) | |
6032 | * | |
853f62a3 MWO |
6033 | * Context: Called with pte lock held. |
6034 | * Return: | |
6035 | * * MC_TARGET_NONE - If the pte is not a target for move charge. | |
6036 | * * MC_TARGET_PAGE - If the page corresponding to this pte is a target for | |
6037 | * move charge. If @target is not NULL, the page is stored in target->page | |
6038 | * with extra refcnt taken (Caller should release it). | |
6039 | * * MC_TARGET_SWAP - If the swap entry corresponding to this pte is a | |
6040 | * target for charge migration. If @target is not NULL, the entry is | |
6041 | * stored in target->ent. | |
6042 | * * MC_TARGET_DEVICE - Like MC_TARGET_PAGE but page is device memory and | |
6043 | * thus not on the lru. For now such page is charged like a regular page | |
6044 | * would be as it is just special memory taking the place of a regular page. | |
6045 | * See Documentations/vm/hmm.txt and include/linux/hmm.h | |
7cf7806c | 6046 | */ |
8d32ff84 | 6047 | static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, |
90254a65 DN |
6048 | unsigned long addr, pte_t ptent, union mc_target *target) |
6049 | { | |
6050 | struct page *page = NULL; | |
8d32ff84 | 6051 | enum mc_target_type ret = MC_TARGET_NONE; |
90254a65 DN |
6052 | swp_entry_t ent = { .val = 0 }; |
6053 | ||
6054 | if (pte_present(ptent)) | |
6055 | page = mc_handle_present_pte(vma, addr, ptent); | |
5c041f5d PX |
6056 | else if (pte_none_mostly(ptent)) |
6057 | /* | |
6058 | * PTE markers should be treated as a none pte here, separated | |
6059 | * from other swap handling below. | |
6060 | */ | |
6061 | page = mc_handle_file_pte(vma, addr, ptent); | |
90254a65 | 6062 | else if (is_swap_pte(ptent)) |
48406ef8 | 6063 | page = mc_handle_swap_pte(vma, ptent, &ent); |
90254a65 | 6064 | |
4e0cf05f JW |
6065 | if (target && page) { |
6066 | if (!trylock_page(page)) { | |
6067 | put_page(page); | |
6068 | return ret; | |
6069 | } | |
6070 | /* | |
6071 | * page_mapped() must be stable during the move. This | |
6072 | * pte is locked, so if it's present, the page cannot | |
6073 | * become unmapped. If it isn't, we have only partial | |
6074 | * control over the mapped state: the page lock will | |
6075 | * prevent new faults against pagecache and swapcache, | |
6076 | * so an unmapped page cannot become mapped. However, | |
6077 | * if the page is already mapped elsewhere, it can | |
6078 | * unmap, and there is nothing we can do about it. | |
6079 | * Alas, skip moving the page in this case. | |
6080 | */ | |
6081 | if (!pte_present(ptent) && page_mapped(page)) { | |
6082 | unlock_page(page); | |
6083 | put_page(page); | |
6084 | return ret; | |
6085 | } | |
6086 | } | |
6087 | ||
90254a65 | 6088 | if (!page && !ent.val) |
8d32ff84 | 6089 | return ret; |
02491447 | 6090 | if (page) { |
02491447 | 6091 | /* |
0a31bc97 | 6092 | * Do only loose check w/o serialization. |
1306a85a | 6093 | * mem_cgroup_move_account() checks the page is valid or |
0a31bc97 | 6094 | * not under LRU exclusion. |
02491447 | 6095 | */ |
bcfe06bf | 6096 | if (page_memcg(page) == mc.from) { |
02491447 | 6097 | ret = MC_TARGET_PAGE; |
f25cbb7a AS |
6098 | if (is_device_private_page(page) || |
6099 | is_device_coherent_page(page)) | |
c733a828 | 6100 | ret = MC_TARGET_DEVICE; |
02491447 DN |
6101 | if (target) |
6102 | target->page = page; | |
6103 | } | |
4e0cf05f JW |
6104 | if (!ret || !target) { |
6105 | if (target) | |
6106 | unlock_page(page); | |
02491447 | 6107 | put_page(page); |
4e0cf05f | 6108 | } |
02491447 | 6109 | } |
3e14a57b HY |
6110 | /* |
6111 | * There is a swap entry and a page doesn't exist or isn't charged. | |
6112 | * But we cannot move a tail-page in a THP. | |
6113 | */ | |
6114 | if (ent.val && !ret && (!page || !PageTransCompound(page)) && | |
34c00c31 | 6115 | mem_cgroup_id(mc.from) == lookup_swap_cgroup_id(ent)) { |
7f0f1546 KH |
6116 | ret = MC_TARGET_SWAP; |
6117 | if (target) | |
6118 | target->ent = ent; | |
4ffef5fe | 6119 | } |
4ffef5fe DN |
6120 | return ret; |
6121 | } | |
6122 | ||
12724850 NH |
6123 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
6124 | /* | |
d6810d73 HY |
6125 | * We don't consider PMD mapped swapping or file mapped pages because THP does |
6126 | * not support them for now. | |
12724850 NH |
6127 | * Caller should make sure that pmd_trans_huge(pmd) is true. |
6128 | */ | |
6129 | static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
6130 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
6131 | { | |
6132 | struct page *page = NULL; | |
12724850 NH |
6133 | enum mc_target_type ret = MC_TARGET_NONE; |
6134 | ||
84c3fc4e ZY |
6135 | if (unlikely(is_swap_pmd(pmd))) { |
6136 | VM_BUG_ON(thp_migration_supported() && | |
6137 | !is_pmd_migration_entry(pmd)); | |
6138 | return ret; | |
6139 | } | |
12724850 | 6140 | page = pmd_page(pmd); |
309381fe | 6141 | VM_BUG_ON_PAGE(!page || !PageHead(page), page); |
1dfab5ab | 6142 | if (!(mc.flags & MOVE_ANON)) |
12724850 | 6143 | return ret; |
bcfe06bf | 6144 | if (page_memcg(page) == mc.from) { |
12724850 NH |
6145 | ret = MC_TARGET_PAGE; |
6146 | if (target) { | |
6147 | get_page(page); | |
4e0cf05f JW |
6148 | if (!trylock_page(page)) { |
6149 | put_page(page); | |
6150 | return MC_TARGET_NONE; | |
6151 | } | |
12724850 NH |
6152 | target->page = page; |
6153 | } | |
6154 | } | |
6155 | return ret; | |
6156 | } | |
6157 | #else | |
6158 | static inline enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
6159 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
6160 | { | |
6161 | return MC_TARGET_NONE; | |
6162 | } | |
6163 | #endif | |
6164 | ||
4ffef5fe DN |
6165 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, |
6166 | unsigned long addr, unsigned long end, | |
6167 | struct mm_walk *walk) | |
6168 | { | |
26bcd64a | 6169 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
6170 | pte_t *pte; |
6171 | spinlock_t *ptl; | |
6172 | ||
b6ec57f4 KS |
6173 | ptl = pmd_trans_huge_lock(pmd, vma); |
6174 | if (ptl) { | |
c733a828 JG |
6175 | /* |
6176 | * Note their can not be MC_TARGET_DEVICE for now as we do not | |
25b2995a CH |
6177 | * support transparent huge page with MEMORY_DEVICE_PRIVATE but |
6178 | * this might change. | |
c733a828 | 6179 | */ |
12724850 NH |
6180 | if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE) |
6181 | mc.precharge += HPAGE_PMD_NR; | |
bf929152 | 6182 | spin_unlock(ptl); |
1a5a9906 | 6183 | return 0; |
12724850 | 6184 | } |
03319327 | 6185 | |
4ffef5fe | 6186 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
04dee9e8 HD |
6187 | if (!pte) |
6188 | return 0; | |
4ffef5fe | 6189 | for (; addr != end; pte++, addr += PAGE_SIZE) |
c33c7948 | 6190 | if (get_mctgt_type(vma, addr, ptep_get(pte), NULL)) |
4ffef5fe DN |
6191 | mc.precharge++; /* increment precharge temporarily */ |
6192 | pte_unmap_unlock(pte - 1, ptl); | |
6193 | cond_resched(); | |
6194 | ||
7dc74be0 DN |
6195 | return 0; |
6196 | } | |
6197 | ||
7b86ac33 CH |
6198 | static const struct mm_walk_ops precharge_walk_ops = { |
6199 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
49b06385 | 6200 | .walk_lock = PGWALK_RDLOCK, |
7b86ac33 CH |
6201 | }; |
6202 | ||
4ffef5fe DN |
6203 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
6204 | { | |
6205 | unsigned long precharge; | |
4ffef5fe | 6206 | |
d8ed45c5 | 6207 | mmap_read_lock(mm); |
ba0aff8e | 6208 | walk_page_range(mm, 0, ULONG_MAX, &precharge_walk_ops, NULL); |
d8ed45c5 | 6209 | mmap_read_unlock(mm); |
4ffef5fe DN |
6210 | |
6211 | precharge = mc.precharge; | |
6212 | mc.precharge = 0; | |
6213 | ||
6214 | return precharge; | |
6215 | } | |
6216 | ||
4ffef5fe DN |
6217 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
6218 | { | |
dfe076b0 DN |
6219 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
6220 | ||
6221 | VM_BUG_ON(mc.moving_task); | |
6222 | mc.moving_task = current; | |
6223 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
6224 | } |
6225 | ||
dfe076b0 DN |
6226 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
6227 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 6228 | { |
2bd9bb20 KH |
6229 | struct mem_cgroup *from = mc.from; |
6230 | struct mem_cgroup *to = mc.to; | |
6231 | ||
4ffef5fe | 6232 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d | 6233 | if (mc.precharge) { |
4b569387 | 6234 | mem_cgroup_cancel_charge(mc.to, mc.precharge); |
854ffa8d DN |
6235 | mc.precharge = 0; |
6236 | } | |
6237 | /* | |
6238 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
6239 | * we must uncharge here. | |
6240 | */ | |
6241 | if (mc.moved_charge) { | |
4b569387 | 6242 | mem_cgroup_cancel_charge(mc.from, mc.moved_charge); |
854ffa8d | 6243 | mc.moved_charge = 0; |
4ffef5fe | 6244 | } |
483c30b5 DN |
6245 | /* we must fixup refcnts and charges */ |
6246 | if (mc.moved_swap) { | |
483c30b5 | 6247 | /* uncharge swap account from the old cgroup */ |
ce00a967 | 6248 | if (!mem_cgroup_is_root(mc.from)) |
3e32cb2e | 6249 | page_counter_uncharge(&mc.from->memsw, mc.moved_swap); |
483c30b5 | 6250 | |
615d66c3 VD |
6251 | mem_cgroup_id_put_many(mc.from, mc.moved_swap); |
6252 | ||
05b84301 | 6253 | /* |
3e32cb2e JW |
6254 | * we charged both to->memory and to->memsw, so we |
6255 | * should uncharge to->memory. | |
05b84301 | 6256 | */ |
ce00a967 | 6257 | if (!mem_cgroup_is_root(mc.to)) |
3e32cb2e JW |
6258 | page_counter_uncharge(&mc.to->memory, mc.moved_swap); |
6259 | ||
483c30b5 DN |
6260 | mc.moved_swap = 0; |
6261 | } | |
dfe076b0 DN |
6262 | memcg_oom_recover(from); |
6263 | memcg_oom_recover(to); | |
6264 | wake_up_all(&mc.waitq); | |
6265 | } | |
6266 | ||
6267 | static void mem_cgroup_clear_mc(void) | |
6268 | { | |
264a0ae1 TH |
6269 | struct mm_struct *mm = mc.mm; |
6270 | ||
dfe076b0 DN |
6271 | /* |
6272 | * we must clear moving_task before waking up waiters at the end of | |
6273 | * task migration. | |
6274 | */ | |
6275 | mc.moving_task = NULL; | |
6276 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 6277 | spin_lock(&mc.lock); |
4ffef5fe DN |
6278 | mc.from = NULL; |
6279 | mc.to = NULL; | |
264a0ae1 | 6280 | mc.mm = NULL; |
2bd9bb20 | 6281 | spin_unlock(&mc.lock); |
264a0ae1 TH |
6282 | |
6283 | mmput(mm); | |
4ffef5fe DN |
6284 | } |
6285 | ||
1f7dd3e5 | 6286 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
7dc74be0 | 6287 | { |
1f7dd3e5 | 6288 | struct cgroup_subsys_state *css; |
eed67d75 | 6289 | struct mem_cgroup *memcg = NULL; /* unneeded init to make gcc happy */ |
9f2115f9 | 6290 | struct mem_cgroup *from; |
4530eddb | 6291 | struct task_struct *leader, *p; |
9f2115f9 | 6292 | struct mm_struct *mm; |
1dfab5ab | 6293 | unsigned long move_flags; |
9f2115f9 | 6294 | int ret = 0; |
7dc74be0 | 6295 | |
1f7dd3e5 TH |
6296 | /* charge immigration isn't supported on the default hierarchy */ |
6297 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
9f2115f9 TH |
6298 | return 0; |
6299 | ||
4530eddb TH |
6300 | /* |
6301 | * Multi-process migrations only happen on the default hierarchy | |
6302 | * where charge immigration is not used. Perform charge | |
6303 | * immigration if @tset contains a leader and whine if there are | |
6304 | * multiple. | |
6305 | */ | |
6306 | p = NULL; | |
1f7dd3e5 | 6307 | cgroup_taskset_for_each_leader(leader, css, tset) { |
4530eddb TH |
6308 | WARN_ON_ONCE(p); |
6309 | p = leader; | |
1f7dd3e5 | 6310 | memcg = mem_cgroup_from_css(css); |
4530eddb TH |
6311 | } |
6312 | if (!p) | |
6313 | return 0; | |
6314 | ||
1f7dd3e5 | 6315 | /* |
f0953a1b | 6316 | * We are now committed to this value whatever it is. Changes in this |
1f7dd3e5 TH |
6317 | * tunable will only affect upcoming migrations, not the current one. |
6318 | * So we need to save it, and keep it going. | |
6319 | */ | |
6320 | move_flags = READ_ONCE(memcg->move_charge_at_immigrate); | |
6321 | if (!move_flags) | |
6322 | return 0; | |
6323 | ||
9f2115f9 TH |
6324 | from = mem_cgroup_from_task(p); |
6325 | ||
6326 | VM_BUG_ON(from == memcg); | |
6327 | ||
6328 | mm = get_task_mm(p); | |
6329 | if (!mm) | |
6330 | return 0; | |
6331 | /* We move charges only when we move a owner of the mm */ | |
6332 | if (mm->owner == p) { | |
6333 | VM_BUG_ON(mc.from); | |
6334 | VM_BUG_ON(mc.to); | |
6335 | VM_BUG_ON(mc.precharge); | |
6336 | VM_BUG_ON(mc.moved_charge); | |
6337 | VM_BUG_ON(mc.moved_swap); | |
6338 | ||
6339 | spin_lock(&mc.lock); | |
264a0ae1 | 6340 | mc.mm = mm; |
9f2115f9 TH |
6341 | mc.from = from; |
6342 | mc.to = memcg; | |
6343 | mc.flags = move_flags; | |
6344 | spin_unlock(&mc.lock); | |
6345 | /* We set mc.moving_task later */ | |
6346 | ||
6347 | ret = mem_cgroup_precharge_mc(mm); | |
6348 | if (ret) | |
6349 | mem_cgroup_clear_mc(); | |
264a0ae1 TH |
6350 | } else { |
6351 | mmput(mm); | |
7dc74be0 DN |
6352 | } |
6353 | return ret; | |
6354 | } | |
6355 | ||
1f7dd3e5 | 6356 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
7dc74be0 | 6357 | { |
4e2f245d JW |
6358 | if (mc.to) |
6359 | mem_cgroup_clear_mc(); | |
7dc74be0 DN |
6360 | } |
6361 | ||
4ffef5fe DN |
6362 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
6363 | unsigned long addr, unsigned long end, | |
6364 | struct mm_walk *walk) | |
7dc74be0 | 6365 | { |
4ffef5fe | 6366 | int ret = 0; |
26bcd64a | 6367 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
6368 | pte_t *pte; |
6369 | spinlock_t *ptl; | |
12724850 NH |
6370 | enum mc_target_type target_type; |
6371 | union mc_target target; | |
6372 | struct page *page; | |
4ffef5fe | 6373 | |
b6ec57f4 KS |
6374 | ptl = pmd_trans_huge_lock(pmd, vma); |
6375 | if (ptl) { | |
62ade86a | 6376 | if (mc.precharge < HPAGE_PMD_NR) { |
bf929152 | 6377 | spin_unlock(ptl); |
12724850 NH |
6378 | return 0; |
6379 | } | |
6380 | target_type = get_mctgt_type_thp(vma, addr, *pmd, &target); | |
6381 | if (target_type == MC_TARGET_PAGE) { | |
6382 | page = target.page; | |
f7f9c00d | 6383 | if (isolate_lru_page(page)) { |
f627c2f5 | 6384 | if (!mem_cgroup_move_account(page, true, |
1306a85a | 6385 | mc.from, mc.to)) { |
12724850 NH |
6386 | mc.precharge -= HPAGE_PMD_NR; |
6387 | mc.moved_charge += HPAGE_PMD_NR; | |
6388 | } | |
6389 | putback_lru_page(page); | |
6390 | } | |
4e0cf05f | 6391 | unlock_page(page); |
12724850 | 6392 | put_page(page); |
c733a828 JG |
6393 | } else if (target_type == MC_TARGET_DEVICE) { |
6394 | page = target.page; | |
6395 | if (!mem_cgroup_move_account(page, true, | |
6396 | mc.from, mc.to)) { | |
6397 | mc.precharge -= HPAGE_PMD_NR; | |
6398 | mc.moved_charge += HPAGE_PMD_NR; | |
6399 | } | |
4e0cf05f | 6400 | unlock_page(page); |
c733a828 | 6401 | put_page(page); |
12724850 | 6402 | } |
bf929152 | 6403 | spin_unlock(ptl); |
1a5a9906 | 6404 | return 0; |
12724850 NH |
6405 | } |
6406 | ||
4ffef5fe DN |
6407 | retry: |
6408 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
04dee9e8 HD |
6409 | if (!pte) |
6410 | return 0; | |
4ffef5fe | 6411 | for (; addr != end; addr += PAGE_SIZE) { |
c33c7948 | 6412 | pte_t ptent = ptep_get(pte++); |
c733a828 | 6413 | bool device = false; |
02491447 | 6414 | swp_entry_t ent; |
4ffef5fe DN |
6415 | |
6416 | if (!mc.precharge) | |
6417 | break; | |
6418 | ||
8d32ff84 | 6419 | switch (get_mctgt_type(vma, addr, ptent, &target)) { |
c733a828 JG |
6420 | case MC_TARGET_DEVICE: |
6421 | device = true; | |
e4a9bc58 | 6422 | fallthrough; |
4ffef5fe DN |
6423 | case MC_TARGET_PAGE: |
6424 | page = target.page; | |
53f9263b KS |
6425 | /* |
6426 | * We can have a part of the split pmd here. Moving it | |
6427 | * can be done but it would be too convoluted so simply | |
6428 | * ignore such a partial THP and keep it in original | |
6429 | * memcg. There should be somebody mapping the head. | |
6430 | */ | |
6431 | if (PageTransCompound(page)) | |
6432 | goto put; | |
f7f9c00d | 6433 | if (!device && !isolate_lru_page(page)) |
4ffef5fe | 6434 | goto put; |
f627c2f5 KS |
6435 | if (!mem_cgroup_move_account(page, false, |
6436 | mc.from, mc.to)) { | |
4ffef5fe | 6437 | mc.precharge--; |
854ffa8d DN |
6438 | /* we uncharge from mc.from later. */ |
6439 | mc.moved_charge++; | |
4ffef5fe | 6440 | } |
c733a828 JG |
6441 | if (!device) |
6442 | putback_lru_page(page); | |
4e0cf05f JW |
6443 | put: /* get_mctgt_type() gets & locks the page */ |
6444 | unlock_page(page); | |
4ffef5fe DN |
6445 | put_page(page); |
6446 | break; | |
02491447 DN |
6447 | case MC_TARGET_SWAP: |
6448 | ent = target.ent; | |
e91cbb42 | 6449 | if (!mem_cgroup_move_swap_account(ent, mc.from, mc.to)) { |
02491447 | 6450 | mc.precharge--; |
8d22a935 HD |
6451 | mem_cgroup_id_get_many(mc.to, 1); |
6452 | /* we fixup other refcnts and charges later. */ | |
483c30b5 DN |
6453 | mc.moved_swap++; |
6454 | } | |
02491447 | 6455 | break; |
4ffef5fe DN |
6456 | default: |
6457 | break; | |
6458 | } | |
6459 | } | |
6460 | pte_unmap_unlock(pte - 1, ptl); | |
6461 | cond_resched(); | |
6462 | ||
6463 | if (addr != end) { | |
6464 | /* | |
6465 | * We have consumed all precharges we got in can_attach(). | |
6466 | * We try charge one by one, but don't do any additional | |
6467 | * charges to mc.to if we have failed in charge once in attach() | |
6468 | * phase. | |
6469 | */ | |
854ffa8d | 6470 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
6471 | if (!ret) |
6472 | goto retry; | |
6473 | } | |
6474 | ||
6475 | return ret; | |
6476 | } | |
6477 | ||
7b86ac33 CH |
6478 | static const struct mm_walk_ops charge_walk_ops = { |
6479 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
49b06385 | 6480 | .walk_lock = PGWALK_RDLOCK, |
7b86ac33 CH |
6481 | }; |
6482 | ||
264a0ae1 | 6483 | static void mem_cgroup_move_charge(void) |
4ffef5fe | 6484 | { |
4ffef5fe | 6485 | lru_add_drain_all(); |
312722cb | 6486 | /* |
6c77b607 | 6487 | * Signal folio_memcg_lock() to take the memcg's move_lock |
81f8c3a4 JW |
6488 | * while we're moving its pages to another memcg. Then wait |
6489 | * for already started RCU-only updates to finish. | |
312722cb JW |
6490 | */ |
6491 | atomic_inc(&mc.from->moving_account); | |
6492 | synchronize_rcu(); | |
dfe076b0 | 6493 | retry: |
d8ed45c5 | 6494 | if (unlikely(!mmap_read_trylock(mc.mm))) { |
dfe076b0 | 6495 | /* |
c1e8d7c6 | 6496 | * Someone who are holding the mmap_lock might be waiting in |
dfe076b0 DN |
6497 | * waitq. So we cancel all extra charges, wake up all waiters, |
6498 | * and retry. Because we cancel precharges, we might not be able | |
6499 | * to move enough charges, but moving charge is a best-effort | |
6500 | * feature anyway, so it wouldn't be a big problem. | |
6501 | */ | |
6502 | __mem_cgroup_clear_mc(); | |
6503 | cond_resched(); | |
6504 | goto retry; | |
6505 | } | |
26bcd64a NH |
6506 | /* |
6507 | * When we have consumed all precharges and failed in doing | |
6508 | * additional charge, the page walk just aborts. | |
6509 | */ | |
ba0aff8e | 6510 | walk_page_range(mc.mm, 0, ULONG_MAX, &charge_walk_ops, NULL); |
d8ed45c5 | 6511 | mmap_read_unlock(mc.mm); |
312722cb | 6512 | atomic_dec(&mc.from->moving_account); |
7dc74be0 DN |
6513 | } |
6514 | ||
264a0ae1 | 6515 | static void mem_cgroup_move_task(void) |
67e465a7 | 6516 | { |
264a0ae1 TH |
6517 | if (mc.to) { |
6518 | mem_cgroup_move_charge(); | |
a433658c | 6519 | mem_cgroup_clear_mc(); |
264a0ae1 | 6520 | } |
67e465a7 | 6521 | } |
1aacbd35 | 6522 | |
5cfb80a7 | 6523 | #else /* !CONFIG_MMU */ |
1f7dd3e5 | 6524 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
6525 | { |
6526 | return 0; | |
6527 | } | |
1f7dd3e5 | 6528 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
6529 | { |
6530 | } | |
264a0ae1 | 6531 | static void mem_cgroup_move_task(void) |
5cfb80a7 DN |
6532 | { |
6533 | } | |
6534 | #endif | |
67e465a7 | 6535 | |
1aacbd35 RG |
6536 | #ifdef CONFIG_MEMCG_KMEM |
6537 | static void mem_cgroup_fork(struct task_struct *task) | |
6538 | { | |
6539 | /* | |
6540 | * Set the update flag to cause task->objcg to be initialized lazily | |
6541 | * on the first allocation. It can be done without any synchronization | |
6542 | * because it's always performed on the current task, so does | |
6543 | * current_objcg_update(). | |
6544 | */ | |
6545 | task->objcg = (struct obj_cgroup *)CURRENT_OBJCG_UPDATE_FLAG; | |
6546 | } | |
6547 | ||
6548 | static void mem_cgroup_exit(struct task_struct *task) | |
6549 | { | |
6550 | struct obj_cgroup *objcg = task->objcg; | |
6551 | ||
6552 | objcg = (struct obj_cgroup *) | |
6553 | ((unsigned long)objcg & ~CURRENT_OBJCG_UPDATE_FLAG); | |
6554 | if (objcg) | |
6555 | obj_cgroup_put(objcg); | |
6556 | ||
6557 | /* | |
6558 | * Some kernel allocations can happen after this point, | |
6559 | * but let's ignore them. It can be done without any synchronization | |
6560 | * because it's always performed on the current task, so does | |
6561 | * current_objcg_update(). | |
6562 | */ | |
6563 | task->objcg = NULL; | |
6564 | } | |
6565 | #endif | |
6566 | ||
bd74fdae | 6567 | #ifdef CONFIG_LRU_GEN |
1aacbd35 | 6568 | static void mem_cgroup_lru_gen_attach(struct cgroup_taskset *tset) |
bd74fdae YZ |
6569 | { |
6570 | struct task_struct *task; | |
6571 | struct cgroup_subsys_state *css; | |
6572 | ||
6573 | /* find the first leader if there is any */ | |
6574 | cgroup_taskset_for_each_leader(task, css, tset) | |
6575 | break; | |
6576 | ||
6577 | if (!task) | |
6578 | return; | |
6579 | ||
6580 | task_lock(task); | |
6581 | if (task->mm && READ_ONCE(task->mm->owner) == task) | |
6582 | lru_gen_migrate_mm(task->mm); | |
6583 | task_unlock(task); | |
6584 | } | |
6585 | #else | |
1aacbd35 RG |
6586 | static void mem_cgroup_lru_gen_attach(struct cgroup_taskset *tset) {} |
6587 | #endif /* CONFIG_LRU_GEN */ | |
6588 | ||
6589 | #ifdef CONFIG_MEMCG_KMEM | |
6590 | static void mem_cgroup_kmem_attach(struct cgroup_taskset *tset) | |
6591 | { | |
6592 | struct task_struct *task; | |
6593 | struct cgroup_subsys_state *css; | |
6594 | ||
6595 | cgroup_taskset_for_each(task, css, tset) { | |
6596 | /* atomically set the update bit */ | |
6597 | set_bit(CURRENT_OBJCG_UPDATE_BIT, (unsigned long *)&task->objcg); | |
6598 | } | |
6599 | } | |
6600 | #else | |
6601 | static void mem_cgroup_kmem_attach(struct cgroup_taskset *tset) {} | |
6602 | #endif /* CONFIG_MEMCG_KMEM */ | |
6603 | ||
6604 | #if defined(CONFIG_LRU_GEN) || defined(CONFIG_MEMCG_KMEM) | |
bd74fdae YZ |
6605 | static void mem_cgroup_attach(struct cgroup_taskset *tset) |
6606 | { | |
1aacbd35 RG |
6607 | mem_cgroup_lru_gen_attach(tset); |
6608 | mem_cgroup_kmem_attach(tset); | |
bd74fdae | 6609 | } |
1aacbd35 | 6610 | #endif |
bd74fdae | 6611 | |
677dc973 CD |
6612 | static int seq_puts_memcg_tunable(struct seq_file *m, unsigned long value) |
6613 | { | |
6614 | if (value == PAGE_COUNTER_MAX) | |
6615 | seq_puts(m, "max\n"); | |
6616 | else | |
6617 | seq_printf(m, "%llu\n", (u64)value * PAGE_SIZE); | |
6618 | ||
6619 | return 0; | |
6620 | } | |
6621 | ||
241994ed JW |
6622 | static u64 memory_current_read(struct cgroup_subsys_state *css, |
6623 | struct cftype *cft) | |
6624 | { | |
f5fc3c5d JW |
6625 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
6626 | ||
6627 | return (u64)page_counter_read(&memcg->memory) * PAGE_SIZE; | |
241994ed JW |
6628 | } |
6629 | ||
8e20d4b3 GR |
6630 | static u64 memory_peak_read(struct cgroup_subsys_state *css, |
6631 | struct cftype *cft) | |
6632 | { | |
6633 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
6634 | ||
6635 | return (u64)memcg->memory.watermark * PAGE_SIZE; | |
6636 | } | |
6637 | ||
bf8d5d52 RG |
6638 | static int memory_min_show(struct seq_file *m, void *v) |
6639 | { | |
677dc973 CD |
6640 | return seq_puts_memcg_tunable(m, |
6641 | READ_ONCE(mem_cgroup_from_seq(m)->memory.min)); | |
bf8d5d52 RG |
6642 | } |
6643 | ||
6644 | static ssize_t memory_min_write(struct kernfs_open_file *of, | |
6645 | char *buf, size_t nbytes, loff_t off) | |
6646 | { | |
6647 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6648 | unsigned long min; | |
6649 | int err; | |
6650 | ||
6651 | buf = strstrip(buf); | |
6652 | err = page_counter_memparse(buf, "max", &min); | |
6653 | if (err) | |
6654 | return err; | |
6655 | ||
6656 | page_counter_set_min(&memcg->memory, min); | |
6657 | ||
6658 | return nbytes; | |
6659 | } | |
6660 | ||
241994ed JW |
6661 | static int memory_low_show(struct seq_file *m, void *v) |
6662 | { | |
677dc973 CD |
6663 | return seq_puts_memcg_tunable(m, |
6664 | READ_ONCE(mem_cgroup_from_seq(m)->memory.low)); | |
241994ed JW |
6665 | } |
6666 | ||
6667 | static ssize_t memory_low_write(struct kernfs_open_file *of, | |
6668 | char *buf, size_t nbytes, loff_t off) | |
6669 | { | |
6670 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6671 | unsigned long low; | |
6672 | int err; | |
6673 | ||
6674 | buf = strstrip(buf); | |
d2973697 | 6675 | err = page_counter_memparse(buf, "max", &low); |
241994ed JW |
6676 | if (err) |
6677 | return err; | |
6678 | ||
23067153 | 6679 | page_counter_set_low(&memcg->memory, low); |
241994ed JW |
6680 | |
6681 | return nbytes; | |
6682 | } | |
6683 | ||
6684 | static int memory_high_show(struct seq_file *m, void *v) | |
6685 | { | |
d1663a90 JK |
6686 | return seq_puts_memcg_tunable(m, |
6687 | READ_ONCE(mem_cgroup_from_seq(m)->memory.high)); | |
241994ed JW |
6688 | } |
6689 | ||
6690 | static ssize_t memory_high_write(struct kernfs_open_file *of, | |
6691 | char *buf, size_t nbytes, loff_t off) | |
6692 | { | |
6693 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
d977aa93 | 6694 | unsigned int nr_retries = MAX_RECLAIM_RETRIES; |
8c8c383c | 6695 | bool drained = false; |
241994ed JW |
6696 | unsigned long high; |
6697 | int err; | |
6698 | ||
6699 | buf = strstrip(buf); | |
d2973697 | 6700 | err = page_counter_memparse(buf, "max", &high); |
241994ed JW |
6701 | if (err) |
6702 | return err; | |
6703 | ||
e82553c1 JW |
6704 | page_counter_set_high(&memcg->memory, high); |
6705 | ||
8c8c383c JW |
6706 | for (;;) { |
6707 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
6708 | unsigned long reclaimed; | |
6709 | ||
6710 | if (nr_pages <= high) | |
6711 | break; | |
6712 | ||
6713 | if (signal_pending(current)) | |
6714 | break; | |
6715 | ||
6716 | if (!drained) { | |
6717 | drain_all_stock(memcg); | |
6718 | drained = true; | |
6719 | continue; | |
6720 | } | |
6721 | ||
6722 | reclaimed = try_to_free_mem_cgroup_pages(memcg, nr_pages - high, | |
55ab834a | 6723 | GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP); |
8c8c383c JW |
6724 | |
6725 | if (!reclaimed && !nr_retries--) | |
6726 | break; | |
6727 | } | |
588083bb | 6728 | |
19ce33ac | 6729 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
6730 | return nbytes; |
6731 | } | |
6732 | ||
6733 | static int memory_max_show(struct seq_file *m, void *v) | |
6734 | { | |
677dc973 CD |
6735 | return seq_puts_memcg_tunable(m, |
6736 | READ_ONCE(mem_cgroup_from_seq(m)->memory.max)); | |
241994ed JW |
6737 | } |
6738 | ||
6739 | static ssize_t memory_max_write(struct kernfs_open_file *of, | |
6740 | char *buf, size_t nbytes, loff_t off) | |
6741 | { | |
6742 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
d977aa93 | 6743 | unsigned int nr_reclaims = MAX_RECLAIM_RETRIES; |
b6e6edcf | 6744 | bool drained = false; |
241994ed JW |
6745 | unsigned long max; |
6746 | int err; | |
6747 | ||
6748 | buf = strstrip(buf); | |
d2973697 | 6749 | err = page_counter_memparse(buf, "max", &max); |
241994ed JW |
6750 | if (err) |
6751 | return err; | |
6752 | ||
bbec2e15 | 6753 | xchg(&memcg->memory.max, max); |
b6e6edcf JW |
6754 | |
6755 | for (;;) { | |
6756 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
6757 | ||
6758 | if (nr_pages <= max) | |
6759 | break; | |
6760 | ||
7249c9f0 | 6761 | if (signal_pending(current)) |
b6e6edcf | 6762 | break; |
b6e6edcf JW |
6763 | |
6764 | if (!drained) { | |
6765 | drain_all_stock(memcg); | |
6766 | drained = true; | |
6767 | continue; | |
6768 | } | |
6769 | ||
6770 | if (nr_reclaims) { | |
6771 | if (!try_to_free_mem_cgroup_pages(memcg, nr_pages - max, | |
55ab834a | 6772 | GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP)) |
b6e6edcf JW |
6773 | nr_reclaims--; |
6774 | continue; | |
6775 | } | |
6776 | ||
e27be240 | 6777 | memcg_memory_event(memcg, MEMCG_OOM); |
b6e6edcf JW |
6778 | if (!mem_cgroup_out_of_memory(memcg, GFP_KERNEL, 0)) |
6779 | break; | |
6780 | } | |
241994ed | 6781 | |
2529bb3a | 6782 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
6783 | return nbytes; |
6784 | } | |
6785 | ||
1e577f97 SB |
6786 | static void __memory_events_show(struct seq_file *m, atomic_long_t *events) |
6787 | { | |
6788 | seq_printf(m, "low %lu\n", atomic_long_read(&events[MEMCG_LOW])); | |
6789 | seq_printf(m, "high %lu\n", atomic_long_read(&events[MEMCG_HIGH])); | |
6790 | seq_printf(m, "max %lu\n", atomic_long_read(&events[MEMCG_MAX])); | |
6791 | seq_printf(m, "oom %lu\n", atomic_long_read(&events[MEMCG_OOM])); | |
6792 | seq_printf(m, "oom_kill %lu\n", | |
6793 | atomic_long_read(&events[MEMCG_OOM_KILL])); | |
b6bf9abb DS |
6794 | seq_printf(m, "oom_group_kill %lu\n", |
6795 | atomic_long_read(&events[MEMCG_OOM_GROUP_KILL])); | |
1e577f97 SB |
6796 | } |
6797 | ||
241994ed JW |
6798 | static int memory_events_show(struct seq_file *m, void *v) |
6799 | { | |
aa9694bb | 6800 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
241994ed | 6801 | |
1e577f97 SB |
6802 | __memory_events_show(m, memcg->memory_events); |
6803 | return 0; | |
6804 | } | |
6805 | ||
6806 | static int memory_events_local_show(struct seq_file *m, void *v) | |
6807 | { | |
6808 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); | |
241994ed | 6809 | |
1e577f97 | 6810 | __memory_events_show(m, memcg->memory_events_local); |
241994ed JW |
6811 | return 0; |
6812 | } | |
6813 | ||
587d9f72 JW |
6814 | static int memory_stat_show(struct seq_file *m, void *v) |
6815 | { | |
aa9694bb | 6816 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
68aaee14 | 6817 | char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL); |
5b42360c | 6818 | struct seq_buf s; |
1ff9e6e1 | 6819 | |
c8713d0b JW |
6820 | if (!buf) |
6821 | return -ENOMEM; | |
5b42360c YA |
6822 | seq_buf_init(&s, buf, PAGE_SIZE); |
6823 | memory_stat_format(memcg, &s); | |
c8713d0b JW |
6824 | seq_puts(m, buf); |
6825 | kfree(buf); | |
587d9f72 JW |
6826 | return 0; |
6827 | } | |
6828 | ||
5f9a4f4a | 6829 | #ifdef CONFIG_NUMA |
fff66b79 MS |
6830 | static inline unsigned long lruvec_page_state_output(struct lruvec *lruvec, |
6831 | int item) | |
6832 | { | |
ff841a06 YA |
6833 | return lruvec_page_state(lruvec, item) * |
6834 | memcg_page_state_output_unit(item); | |
fff66b79 MS |
6835 | } |
6836 | ||
5f9a4f4a MS |
6837 | static int memory_numa_stat_show(struct seq_file *m, void *v) |
6838 | { | |
6839 | int i; | |
6840 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); | |
6841 | ||
fd25a9e0 | 6842 | mem_cgroup_flush_stats(); |
7e1c0d6f | 6843 | |
5f9a4f4a MS |
6844 | for (i = 0; i < ARRAY_SIZE(memory_stats); i++) { |
6845 | int nid; | |
6846 | ||
6847 | if (memory_stats[i].idx >= NR_VM_NODE_STAT_ITEMS) | |
6848 | continue; | |
6849 | ||
6850 | seq_printf(m, "%s", memory_stats[i].name); | |
6851 | for_each_node_state(nid, N_MEMORY) { | |
6852 | u64 size; | |
6853 | struct lruvec *lruvec; | |
6854 | ||
6855 | lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); | |
fff66b79 MS |
6856 | size = lruvec_page_state_output(lruvec, |
6857 | memory_stats[i].idx); | |
5f9a4f4a MS |
6858 | seq_printf(m, " N%d=%llu", nid, size); |
6859 | } | |
6860 | seq_putc(m, '\n'); | |
6861 | } | |
6862 | ||
6863 | return 0; | |
6864 | } | |
6865 | #endif | |
6866 | ||
3d8b38eb RG |
6867 | static int memory_oom_group_show(struct seq_file *m, void *v) |
6868 | { | |
aa9694bb | 6869 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
3d8b38eb | 6870 | |
eaf7b66b | 6871 | seq_printf(m, "%d\n", READ_ONCE(memcg->oom_group)); |
3d8b38eb RG |
6872 | |
6873 | return 0; | |
6874 | } | |
6875 | ||
6876 | static ssize_t memory_oom_group_write(struct kernfs_open_file *of, | |
6877 | char *buf, size_t nbytes, loff_t off) | |
6878 | { | |
6879 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6880 | int ret, oom_group; | |
6881 | ||
6882 | buf = strstrip(buf); | |
6883 | if (!buf) | |
6884 | return -EINVAL; | |
6885 | ||
6886 | ret = kstrtoint(buf, 0, &oom_group); | |
6887 | if (ret) | |
6888 | return ret; | |
6889 | ||
6890 | if (oom_group != 0 && oom_group != 1) | |
6891 | return -EINVAL; | |
6892 | ||
eaf7b66b | 6893 | WRITE_ONCE(memcg->oom_group, oom_group); |
3d8b38eb RG |
6894 | |
6895 | return nbytes; | |
6896 | } | |
6897 | ||
94968384 SB |
6898 | static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf, |
6899 | size_t nbytes, loff_t off) | |
6900 | { | |
6901 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6902 | unsigned int nr_retries = MAX_RECLAIM_RETRIES; | |
6903 | unsigned long nr_to_reclaim, nr_reclaimed = 0; | |
55ab834a MH |
6904 | unsigned int reclaim_options; |
6905 | int err; | |
12a5d395 MA |
6906 | |
6907 | buf = strstrip(buf); | |
55ab834a MH |
6908 | err = page_counter_memparse(buf, "", &nr_to_reclaim); |
6909 | if (err) | |
6910 | return err; | |
12a5d395 | 6911 | |
55ab834a | 6912 | reclaim_options = MEMCG_RECLAIM_MAY_SWAP | MEMCG_RECLAIM_PROACTIVE; |
94968384 SB |
6913 | while (nr_reclaimed < nr_to_reclaim) { |
6914 | unsigned long reclaimed; | |
6915 | ||
6916 | if (signal_pending(current)) | |
6917 | return -EINTR; | |
6918 | ||
6919 | /* | |
6920 | * This is the final attempt, drain percpu lru caches in the | |
6921 | * hope of introducing more evictable pages for | |
6922 | * try_to_free_mem_cgroup_pages(). | |
6923 | */ | |
6924 | if (!nr_retries) | |
6925 | lru_add_drain_all(); | |
6926 | ||
6927 | reclaimed = try_to_free_mem_cgroup_pages(memcg, | |
0388536a EY |
6928 | min(nr_to_reclaim - nr_reclaimed, SWAP_CLUSTER_MAX), |
6929 | GFP_KERNEL, reclaim_options); | |
94968384 SB |
6930 | |
6931 | if (!reclaimed && !nr_retries--) | |
6932 | return -EAGAIN; | |
6933 | ||
6934 | nr_reclaimed += reclaimed; | |
6935 | } | |
6936 | ||
6937 | return nbytes; | |
6938 | } | |
6939 | ||
241994ed JW |
6940 | static struct cftype memory_files[] = { |
6941 | { | |
6942 | .name = "current", | |
f5fc3c5d | 6943 | .flags = CFTYPE_NOT_ON_ROOT, |
241994ed JW |
6944 | .read_u64 = memory_current_read, |
6945 | }, | |
8e20d4b3 GR |
6946 | { |
6947 | .name = "peak", | |
6948 | .flags = CFTYPE_NOT_ON_ROOT, | |
6949 | .read_u64 = memory_peak_read, | |
6950 | }, | |
bf8d5d52 RG |
6951 | { |
6952 | .name = "min", | |
6953 | .flags = CFTYPE_NOT_ON_ROOT, | |
6954 | .seq_show = memory_min_show, | |
6955 | .write = memory_min_write, | |
6956 | }, | |
241994ed JW |
6957 | { |
6958 | .name = "low", | |
6959 | .flags = CFTYPE_NOT_ON_ROOT, | |
6960 | .seq_show = memory_low_show, | |
6961 | .write = memory_low_write, | |
6962 | }, | |
6963 | { | |
6964 | .name = "high", | |
6965 | .flags = CFTYPE_NOT_ON_ROOT, | |
6966 | .seq_show = memory_high_show, | |
6967 | .write = memory_high_write, | |
6968 | }, | |
6969 | { | |
6970 | .name = "max", | |
6971 | .flags = CFTYPE_NOT_ON_ROOT, | |
6972 | .seq_show = memory_max_show, | |
6973 | .write = memory_max_write, | |
6974 | }, | |
6975 | { | |
6976 | .name = "events", | |
6977 | .flags = CFTYPE_NOT_ON_ROOT, | |
472912a2 | 6978 | .file_offset = offsetof(struct mem_cgroup, events_file), |
241994ed JW |
6979 | .seq_show = memory_events_show, |
6980 | }, | |
1e577f97 SB |
6981 | { |
6982 | .name = "events.local", | |
6983 | .flags = CFTYPE_NOT_ON_ROOT, | |
6984 | .file_offset = offsetof(struct mem_cgroup, events_local_file), | |
6985 | .seq_show = memory_events_local_show, | |
6986 | }, | |
587d9f72 JW |
6987 | { |
6988 | .name = "stat", | |
587d9f72 JW |
6989 | .seq_show = memory_stat_show, |
6990 | }, | |
5f9a4f4a MS |
6991 | #ifdef CONFIG_NUMA |
6992 | { | |
6993 | .name = "numa_stat", | |
6994 | .seq_show = memory_numa_stat_show, | |
6995 | }, | |
6996 | #endif | |
3d8b38eb RG |
6997 | { |
6998 | .name = "oom.group", | |
6999 | .flags = CFTYPE_NOT_ON_ROOT | CFTYPE_NS_DELEGATABLE, | |
7000 | .seq_show = memory_oom_group_show, | |
7001 | .write = memory_oom_group_write, | |
7002 | }, | |
94968384 SB |
7003 | { |
7004 | .name = "reclaim", | |
7005 | .flags = CFTYPE_NS_DELEGATABLE, | |
7006 | .write = memory_reclaim, | |
7007 | }, | |
241994ed JW |
7008 | { } /* terminate */ |
7009 | }; | |
7010 | ||
073219e9 | 7011 | struct cgroup_subsys memory_cgrp_subsys = { |
92fb9748 | 7012 | .css_alloc = mem_cgroup_css_alloc, |
d142e3e6 | 7013 | .css_online = mem_cgroup_css_online, |
92fb9748 | 7014 | .css_offline = mem_cgroup_css_offline, |
6df38689 | 7015 | .css_released = mem_cgroup_css_released, |
92fb9748 | 7016 | .css_free = mem_cgroup_css_free, |
1ced953b | 7017 | .css_reset = mem_cgroup_css_reset, |
2d146aa3 | 7018 | .css_rstat_flush = mem_cgroup_css_rstat_flush, |
7dc74be0 | 7019 | .can_attach = mem_cgroup_can_attach, |
1aacbd35 | 7020 | #if defined(CONFIG_LRU_GEN) || defined(CONFIG_MEMCG_KMEM) |
bd74fdae | 7021 | .attach = mem_cgroup_attach, |
1aacbd35 | 7022 | #endif |
7dc74be0 | 7023 | .cancel_attach = mem_cgroup_cancel_attach, |
264a0ae1 | 7024 | .post_attach = mem_cgroup_move_task, |
1aacbd35 RG |
7025 | #ifdef CONFIG_MEMCG_KMEM |
7026 | .fork = mem_cgroup_fork, | |
7027 | .exit = mem_cgroup_exit, | |
7028 | #endif | |
241994ed JW |
7029 | .dfl_cftypes = memory_files, |
7030 | .legacy_cftypes = mem_cgroup_legacy_files, | |
6d12e2d8 | 7031 | .early_init = 0, |
8cdea7c0 | 7032 | }; |
c077719b | 7033 | |
bc50bcc6 JW |
7034 | /* |
7035 | * This function calculates an individual cgroup's effective | |
7036 | * protection which is derived from its own memory.min/low, its | |
7037 | * parent's and siblings' settings, as well as the actual memory | |
7038 | * distribution in the tree. | |
7039 | * | |
7040 | * The following rules apply to the effective protection values: | |
7041 | * | |
7042 | * 1. At the first level of reclaim, effective protection is equal to | |
7043 | * the declared protection in memory.min and memory.low. | |
7044 | * | |
7045 | * 2. To enable safe delegation of the protection configuration, at | |
7046 | * subsequent levels the effective protection is capped to the | |
7047 | * parent's effective protection. | |
7048 | * | |
7049 | * 3. To make complex and dynamic subtrees easier to configure, the | |
7050 | * user is allowed to overcommit the declared protection at a given | |
7051 | * level. If that is the case, the parent's effective protection is | |
7052 | * distributed to the children in proportion to how much protection | |
7053 | * they have declared and how much of it they are utilizing. | |
7054 | * | |
7055 | * This makes distribution proportional, but also work-conserving: | |
7056 | * if one cgroup claims much more protection than it uses memory, | |
7057 | * the unused remainder is available to its siblings. | |
7058 | * | |
7059 | * 4. Conversely, when the declared protection is undercommitted at a | |
7060 | * given level, the distribution of the larger parental protection | |
7061 | * budget is NOT proportional. A cgroup's protection from a sibling | |
7062 | * is capped to its own memory.min/low setting. | |
7063 | * | |
8a931f80 JW |
7064 | * 5. However, to allow protecting recursive subtrees from each other |
7065 | * without having to declare each individual cgroup's fixed share | |
7066 | * of the ancestor's claim to protection, any unutilized - | |
7067 | * "floating" - protection from up the tree is distributed in | |
7068 | * proportion to each cgroup's *usage*. This makes the protection | |
7069 | * neutral wrt sibling cgroups and lets them compete freely over | |
7070 | * the shared parental protection budget, but it protects the | |
7071 | * subtree as a whole from neighboring subtrees. | |
7072 | * | |
7073 | * Note that 4. and 5. are not in conflict: 4. is about protecting | |
7074 | * against immediate siblings whereas 5. is about protecting against | |
7075 | * neighboring subtrees. | |
bc50bcc6 JW |
7076 | */ |
7077 | static unsigned long effective_protection(unsigned long usage, | |
8a931f80 | 7078 | unsigned long parent_usage, |
bc50bcc6 JW |
7079 | unsigned long setting, |
7080 | unsigned long parent_effective, | |
7081 | unsigned long siblings_protected) | |
7082 | { | |
7083 | unsigned long protected; | |
8a931f80 | 7084 | unsigned long ep; |
bc50bcc6 JW |
7085 | |
7086 | protected = min(usage, setting); | |
7087 | /* | |
7088 | * If all cgroups at this level combined claim and use more | |
08e0f49e | 7089 | * protection than what the parent affords them, distribute |
bc50bcc6 JW |
7090 | * shares in proportion to utilization. |
7091 | * | |
7092 | * We are using actual utilization rather than the statically | |
7093 | * claimed protection in order to be work-conserving: claimed | |
7094 | * but unused protection is available to siblings that would | |
7095 | * otherwise get a smaller chunk than what they claimed. | |
7096 | */ | |
7097 | if (siblings_protected > parent_effective) | |
7098 | return protected * parent_effective / siblings_protected; | |
7099 | ||
7100 | /* | |
7101 | * Ok, utilized protection of all children is within what the | |
7102 | * parent affords them, so we know whatever this child claims | |
7103 | * and utilizes is effectively protected. | |
7104 | * | |
7105 | * If there is unprotected usage beyond this value, reclaim | |
7106 | * will apply pressure in proportion to that amount. | |
7107 | * | |
7108 | * If there is unutilized protection, the cgroup will be fully | |
7109 | * shielded from reclaim, but we do return a smaller value for | |
7110 | * protection than what the group could enjoy in theory. This | |
7111 | * is okay. With the overcommit distribution above, effective | |
7112 | * protection is always dependent on how memory is actually | |
7113 | * consumed among the siblings anyway. | |
7114 | */ | |
8a931f80 JW |
7115 | ep = protected; |
7116 | ||
7117 | /* | |
7118 | * If the children aren't claiming (all of) the protection | |
7119 | * afforded to them by the parent, distribute the remainder in | |
7120 | * proportion to the (unprotected) memory of each cgroup. That | |
7121 | * way, cgroups that aren't explicitly prioritized wrt each | |
7122 | * other compete freely over the allowance, but they are | |
7123 | * collectively protected from neighboring trees. | |
7124 | * | |
7125 | * We're using unprotected memory for the weight so that if | |
7126 | * some cgroups DO claim explicit protection, we don't protect | |
7127 | * the same bytes twice. | |
cd324edc JW |
7128 | * |
7129 | * Check both usage and parent_usage against the respective | |
7130 | * protected values. One should imply the other, but they | |
7131 | * aren't read atomically - make sure the division is sane. | |
8a931f80 JW |
7132 | */ |
7133 | if (!(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_RECURSIVE_PROT)) | |
7134 | return ep; | |
cd324edc JW |
7135 | if (parent_effective > siblings_protected && |
7136 | parent_usage > siblings_protected && | |
7137 | usage > protected) { | |
8a931f80 JW |
7138 | unsigned long unclaimed; |
7139 | ||
7140 | unclaimed = parent_effective - siblings_protected; | |
7141 | unclaimed *= usage - protected; | |
7142 | unclaimed /= parent_usage - siblings_protected; | |
7143 | ||
7144 | ep += unclaimed; | |
7145 | } | |
7146 | ||
7147 | return ep; | |
bc50bcc6 JW |
7148 | } |
7149 | ||
241994ed | 7150 | /** |
05395718 | 7151 | * mem_cgroup_calculate_protection - check if memory consumption is in the normal range |
34c81057 | 7152 | * @root: the top ancestor of the sub-tree being checked |
241994ed JW |
7153 | * @memcg: the memory cgroup to check |
7154 | * | |
23067153 RG |
7155 | * WARNING: This function is not stateless! It can only be used as part |
7156 | * of a top-down tree iteration, not for isolated queries. | |
241994ed | 7157 | */ |
45c7f7e1 CD |
7158 | void mem_cgroup_calculate_protection(struct mem_cgroup *root, |
7159 | struct mem_cgroup *memcg) | |
241994ed | 7160 | { |
8a931f80 | 7161 | unsigned long usage, parent_usage; |
23067153 RG |
7162 | struct mem_cgroup *parent; |
7163 | ||
241994ed | 7164 | if (mem_cgroup_disabled()) |
45c7f7e1 | 7165 | return; |
241994ed | 7166 | |
34c81057 SC |
7167 | if (!root) |
7168 | root = root_mem_cgroup; | |
22f7496f YS |
7169 | |
7170 | /* | |
7171 | * Effective values of the reclaim targets are ignored so they | |
7172 | * can be stale. Have a look at mem_cgroup_protection for more | |
7173 | * details. | |
7174 | * TODO: calculation should be more robust so that we do not need | |
7175 | * that special casing. | |
7176 | */ | |
34c81057 | 7177 | if (memcg == root) |
45c7f7e1 | 7178 | return; |
241994ed | 7179 | |
23067153 | 7180 | usage = page_counter_read(&memcg->memory); |
bf8d5d52 | 7181 | if (!usage) |
45c7f7e1 | 7182 | return; |
bf8d5d52 | 7183 | |
bf8d5d52 | 7184 | parent = parent_mem_cgroup(memcg); |
df2a4196 | 7185 | |
bc50bcc6 | 7186 | if (parent == root) { |
c3d53200 | 7187 | memcg->memory.emin = READ_ONCE(memcg->memory.min); |
03960e33 | 7188 | memcg->memory.elow = READ_ONCE(memcg->memory.low); |
45c7f7e1 | 7189 | return; |
bf8d5d52 RG |
7190 | } |
7191 | ||
8a931f80 JW |
7192 | parent_usage = page_counter_read(&parent->memory); |
7193 | ||
b3a7822e | 7194 | WRITE_ONCE(memcg->memory.emin, effective_protection(usage, parent_usage, |
c3d53200 CD |
7195 | READ_ONCE(memcg->memory.min), |
7196 | READ_ONCE(parent->memory.emin), | |
b3a7822e | 7197 | atomic_long_read(&parent->memory.children_min_usage))); |
23067153 | 7198 | |
b3a7822e | 7199 | WRITE_ONCE(memcg->memory.elow, effective_protection(usage, parent_usage, |
03960e33 CD |
7200 | READ_ONCE(memcg->memory.low), |
7201 | READ_ONCE(parent->memory.elow), | |
b3a7822e | 7202 | atomic_long_read(&parent->memory.children_low_usage))); |
241994ed JW |
7203 | } |
7204 | ||
8f425e4e MWO |
7205 | static int charge_memcg(struct folio *folio, struct mem_cgroup *memcg, |
7206 | gfp_t gfp) | |
0add0c77 | 7207 | { |
0add0c77 SB |
7208 | int ret; |
7209 | ||
4b569387 | 7210 | ret = try_charge(memcg, gfp, folio_nr_pages(folio)); |
0add0c77 SB |
7211 | if (ret) |
7212 | goto out; | |
7213 | ||
4b569387 | 7214 | mem_cgroup_commit_charge(folio, memcg); |
0add0c77 SB |
7215 | out: |
7216 | return ret; | |
7217 | } | |
7218 | ||
8f425e4e | 7219 | int __mem_cgroup_charge(struct folio *folio, struct mm_struct *mm, gfp_t gfp) |
00501b53 | 7220 | { |
0add0c77 SB |
7221 | struct mem_cgroup *memcg; |
7222 | int ret; | |
00501b53 | 7223 | |
0add0c77 | 7224 | memcg = get_mem_cgroup_from_mm(mm); |
8f425e4e | 7225 | ret = charge_memcg(folio, memcg, gfp); |
0add0c77 | 7226 | css_put(&memcg->css); |
2d1c4980 | 7227 | |
0add0c77 SB |
7228 | return ret; |
7229 | } | |
e993d905 | 7230 | |
8cba9576 NP |
7231 | /** |
7232 | * mem_cgroup_hugetlb_try_charge - try to charge the memcg for a hugetlb folio | |
7233 | * @memcg: memcg to charge. | |
7234 | * @gfp: reclaim mode. | |
7235 | * @nr_pages: number of pages to charge. | |
7236 | * | |
7237 | * This function is called when allocating a huge page folio to determine if | |
7238 | * the memcg has the capacity for it. It does not commit the charge yet, | |
7239 | * as the hugetlb folio itself has not been obtained from the hugetlb pool. | |
7240 | * | |
7241 | * Once we have obtained the hugetlb folio, we can call | |
7242 | * mem_cgroup_commit_charge() to commit the charge. If we fail to obtain the | |
7243 | * folio, we should instead call mem_cgroup_cancel_charge() to undo the effect | |
7244 | * of try_charge(). | |
7245 | * | |
7246 | * Returns 0 on success. Otherwise, an error code is returned. | |
7247 | */ | |
7248 | int mem_cgroup_hugetlb_try_charge(struct mem_cgroup *memcg, gfp_t gfp, | |
7249 | long nr_pages) | |
7250 | { | |
7251 | /* | |
7252 | * If hugetlb memcg charging is not enabled, do not fail hugetlb allocation, | |
7253 | * but do not attempt to commit charge later (or cancel on error) either. | |
7254 | */ | |
7255 | if (mem_cgroup_disabled() || !memcg || | |
7256 | !cgroup_subsys_on_dfl(memory_cgrp_subsys) || | |
7257 | !(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING)) | |
7258 | return -EOPNOTSUPP; | |
7259 | ||
7260 | if (try_charge(memcg, gfp, nr_pages)) | |
7261 | return -ENOMEM; | |
7262 | ||
7263 | return 0; | |
7264 | } | |
7265 | ||
0add0c77 | 7266 | /** |
65995918 MWO |
7267 | * mem_cgroup_swapin_charge_folio - Charge a newly allocated folio for swapin. |
7268 | * @folio: folio to charge. | |
0add0c77 SB |
7269 | * @mm: mm context of the victim |
7270 | * @gfp: reclaim mode | |
65995918 | 7271 | * @entry: swap entry for which the folio is allocated |
0add0c77 | 7272 | * |
65995918 MWO |
7273 | * This function charges a folio allocated for swapin. Please call this before |
7274 | * adding the folio to the swapcache. | |
0add0c77 SB |
7275 | * |
7276 | * Returns 0 on success. Otherwise, an error code is returned. | |
7277 | */ | |
65995918 | 7278 | int mem_cgroup_swapin_charge_folio(struct folio *folio, struct mm_struct *mm, |
0add0c77 SB |
7279 | gfp_t gfp, swp_entry_t entry) |
7280 | { | |
7281 | struct mem_cgroup *memcg; | |
7282 | unsigned short id; | |
7283 | int ret; | |
00501b53 | 7284 | |
0add0c77 SB |
7285 | if (mem_cgroup_disabled()) |
7286 | return 0; | |
00501b53 | 7287 | |
0add0c77 SB |
7288 | id = lookup_swap_cgroup_id(entry); |
7289 | rcu_read_lock(); | |
7290 | memcg = mem_cgroup_from_id(id); | |
7291 | if (!memcg || !css_tryget_online(&memcg->css)) | |
7292 | memcg = get_mem_cgroup_from_mm(mm); | |
7293 | rcu_read_unlock(); | |
00501b53 | 7294 | |
8f425e4e | 7295 | ret = charge_memcg(folio, memcg, gfp); |
6abb5a86 | 7296 | |
0add0c77 SB |
7297 | css_put(&memcg->css); |
7298 | return ret; | |
7299 | } | |
00501b53 | 7300 | |
0add0c77 SB |
7301 | /* |
7302 | * mem_cgroup_swapin_uncharge_swap - uncharge swap slot | |
7303 | * @entry: swap entry for which the page is charged | |
7304 | * | |
7305 | * Call this function after successfully adding the charged page to swapcache. | |
7306 | * | |
7307 | * Note: This function assumes the page for which swap slot is being uncharged | |
7308 | * is order 0 page. | |
7309 | */ | |
7310 | void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry) | |
7311 | { | |
cae3af62 MS |
7312 | /* |
7313 | * Cgroup1's unified memory+swap counter has been charged with the | |
7314 | * new swapcache page, finish the transfer by uncharging the swap | |
7315 | * slot. The swap slot would also get uncharged when it dies, but | |
7316 | * it can stick around indefinitely and we'd count the page twice | |
7317 | * the entire time. | |
7318 | * | |
7319 | * Cgroup2 has separate resource counters for memory and swap, | |
7320 | * so this is a non-issue here. Memory and swap charge lifetimes | |
7321 | * correspond 1:1 to page and swap slot lifetimes: we charge the | |
7322 | * page to memory here, and uncharge swap when the slot is freed. | |
7323 | */ | |
0add0c77 | 7324 | if (!mem_cgroup_disabled() && do_memsw_account()) { |
00501b53 JW |
7325 | /* |
7326 | * The swap entry might not get freed for a long time, | |
7327 | * let's not wait for it. The page already received a | |
7328 | * memory+swap charge, drop the swap entry duplicate. | |
7329 | */ | |
0add0c77 | 7330 | mem_cgroup_uncharge_swap(entry, 1); |
00501b53 | 7331 | } |
3fea5a49 JW |
7332 | } |
7333 | ||
a9d5adee JG |
7334 | struct uncharge_gather { |
7335 | struct mem_cgroup *memcg; | |
b4e0b68f | 7336 | unsigned long nr_memory; |
a9d5adee | 7337 | unsigned long pgpgout; |
a9d5adee | 7338 | unsigned long nr_kmem; |
8e88bd2d | 7339 | int nid; |
a9d5adee JG |
7340 | }; |
7341 | ||
7342 | static inline void uncharge_gather_clear(struct uncharge_gather *ug) | |
747db954 | 7343 | { |
a9d5adee JG |
7344 | memset(ug, 0, sizeof(*ug)); |
7345 | } | |
7346 | ||
7347 | static void uncharge_batch(const struct uncharge_gather *ug) | |
7348 | { | |
747db954 JW |
7349 | unsigned long flags; |
7350 | ||
b4e0b68f MS |
7351 | if (ug->nr_memory) { |
7352 | page_counter_uncharge(&ug->memcg->memory, ug->nr_memory); | |
7941d214 | 7353 | if (do_memsw_account()) |
b4e0b68f | 7354 | page_counter_uncharge(&ug->memcg->memsw, ug->nr_memory); |
a8c49af3 YA |
7355 | if (ug->nr_kmem) |
7356 | memcg_account_kmem(ug->memcg, -ug->nr_kmem); | |
a9d5adee | 7357 | memcg_oom_recover(ug->memcg); |
ce00a967 | 7358 | } |
747db954 JW |
7359 | |
7360 | local_irq_save(flags); | |
c9019e9b | 7361 | __count_memcg_events(ug->memcg, PGPGOUT, ug->pgpgout); |
b4e0b68f | 7362 | __this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, ug->nr_memory); |
8e88bd2d | 7363 | memcg_check_events(ug->memcg, ug->nid); |
747db954 | 7364 | local_irq_restore(flags); |
f1796544 | 7365 | |
c4ed6ebf | 7366 | /* drop reference from uncharge_folio */ |
f1796544 | 7367 | css_put(&ug->memcg->css); |
a9d5adee JG |
7368 | } |
7369 | ||
c4ed6ebf | 7370 | static void uncharge_folio(struct folio *folio, struct uncharge_gather *ug) |
a9d5adee | 7371 | { |
c4ed6ebf | 7372 | long nr_pages; |
b4e0b68f MS |
7373 | struct mem_cgroup *memcg; |
7374 | struct obj_cgroup *objcg; | |
9f762dbe | 7375 | |
c4ed6ebf | 7376 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
a9d5adee | 7377 | |
a9d5adee JG |
7378 | /* |
7379 | * Nobody should be changing or seriously looking at | |
c4ed6ebf MWO |
7380 | * folio memcg or objcg at this point, we have fully |
7381 | * exclusive access to the folio. | |
a9d5adee | 7382 | */ |
fead2b86 | 7383 | if (folio_memcg_kmem(folio)) { |
1b7e4464 | 7384 | objcg = __folio_objcg(folio); |
b4e0b68f MS |
7385 | /* |
7386 | * This get matches the put at the end of the function and | |
7387 | * kmem pages do not hold memcg references anymore. | |
7388 | */ | |
7389 | memcg = get_mem_cgroup_from_objcg(objcg); | |
7390 | } else { | |
1b7e4464 | 7391 | memcg = __folio_memcg(folio); |
b4e0b68f | 7392 | } |
a9d5adee | 7393 | |
b4e0b68f MS |
7394 | if (!memcg) |
7395 | return; | |
7396 | ||
7397 | if (ug->memcg != memcg) { | |
a9d5adee JG |
7398 | if (ug->memcg) { |
7399 | uncharge_batch(ug); | |
7400 | uncharge_gather_clear(ug); | |
7401 | } | |
b4e0b68f | 7402 | ug->memcg = memcg; |
c4ed6ebf | 7403 | ug->nid = folio_nid(folio); |
f1796544 MH |
7404 | |
7405 | /* pairs with css_put in uncharge_batch */ | |
b4e0b68f | 7406 | css_get(&memcg->css); |
a9d5adee JG |
7407 | } |
7408 | ||
c4ed6ebf | 7409 | nr_pages = folio_nr_pages(folio); |
a9d5adee | 7410 | |
fead2b86 | 7411 | if (folio_memcg_kmem(folio)) { |
b4e0b68f | 7412 | ug->nr_memory += nr_pages; |
9f762dbe | 7413 | ug->nr_kmem += nr_pages; |
b4e0b68f | 7414 | |
c4ed6ebf | 7415 | folio->memcg_data = 0; |
b4e0b68f MS |
7416 | obj_cgroup_put(objcg); |
7417 | } else { | |
7418 | /* LRU pages aren't accounted at the root level */ | |
7419 | if (!mem_cgroup_is_root(memcg)) | |
7420 | ug->nr_memory += nr_pages; | |
18b2db3b | 7421 | ug->pgpgout++; |
a9d5adee | 7422 | |
c4ed6ebf | 7423 | folio->memcg_data = 0; |
b4e0b68f MS |
7424 | } |
7425 | ||
7426 | css_put(&memcg->css); | |
747db954 JW |
7427 | } |
7428 | ||
bbc6b703 | 7429 | void __mem_cgroup_uncharge(struct folio *folio) |
0a31bc97 | 7430 | { |
a9d5adee JG |
7431 | struct uncharge_gather ug; |
7432 | ||
bbc6b703 MWO |
7433 | /* Don't touch folio->lru of any random page, pre-check: */ |
7434 | if (!folio_memcg(folio)) | |
0a31bc97 JW |
7435 | return; |
7436 | ||
a9d5adee | 7437 | uncharge_gather_clear(&ug); |
bbc6b703 | 7438 | uncharge_folio(folio, &ug); |
a9d5adee | 7439 | uncharge_batch(&ug); |
747db954 | 7440 | } |
0a31bc97 | 7441 | |
747db954 | 7442 | /** |
2c8d8f97 | 7443 | * __mem_cgroup_uncharge_list - uncharge a list of page |
747db954 JW |
7444 | * @page_list: list of pages to uncharge |
7445 | * | |
7446 | * Uncharge a list of pages previously charged with | |
2c8d8f97 | 7447 | * __mem_cgroup_charge(). |
747db954 | 7448 | */ |
2c8d8f97 | 7449 | void __mem_cgroup_uncharge_list(struct list_head *page_list) |
747db954 | 7450 | { |
c41a40b6 | 7451 | struct uncharge_gather ug; |
c4ed6ebf | 7452 | struct folio *folio; |
c41a40b6 | 7453 | |
c41a40b6 | 7454 | uncharge_gather_clear(&ug); |
c4ed6ebf MWO |
7455 | list_for_each_entry(folio, page_list, lru) |
7456 | uncharge_folio(folio, &ug); | |
c41a40b6 MS |
7457 | if (ug.memcg) |
7458 | uncharge_batch(&ug); | |
0a31bc97 JW |
7459 | } |
7460 | ||
7461 | /** | |
85ce2c51 | 7462 | * mem_cgroup_replace_folio - Charge a folio's replacement. |
d21bba2b MWO |
7463 | * @old: Currently circulating folio. |
7464 | * @new: Replacement folio. | |
0a31bc97 | 7465 | * |
d21bba2b | 7466 | * Charge @new as a replacement folio for @old. @old will |
85ce2c51 NP |
7467 | * be uncharged upon free. This is only used by the page cache |
7468 | * (in replace_page_cache_folio()). | |
0a31bc97 | 7469 | * |
d21bba2b | 7470 | * Both folios must be locked, @new->mapping must be set up. |
0a31bc97 | 7471 | */ |
85ce2c51 | 7472 | void mem_cgroup_replace_folio(struct folio *old, struct folio *new) |
0a31bc97 | 7473 | { |
29833315 | 7474 | struct mem_cgroup *memcg; |
d21bba2b | 7475 | long nr_pages = folio_nr_pages(new); |
d93c4130 | 7476 | unsigned long flags; |
0a31bc97 | 7477 | |
d21bba2b MWO |
7478 | VM_BUG_ON_FOLIO(!folio_test_locked(old), old); |
7479 | VM_BUG_ON_FOLIO(!folio_test_locked(new), new); | |
7480 | VM_BUG_ON_FOLIO(folio_test_anon(old) != folio_test_anon(new), new); | |
7481 | VM_BUG_ON_FOLIO(folio_nr_pages(old) != nr_pages, new); | |
0a31bc97 JW |
7482 | |
7483 | if (mem_cgroup_disabled()) | |
7484 | return; | |
7485 | ||
d21bba2b MWO |
7486 | /* Page cache replacement: new folio already charged? */ |
7487 | if (folio_memcg(new)) | |
0a31bc97 JW |
7488 | return; |
7489 | ||
d21bba2b MWO |
7490 | memcg = folio_memcg(old); |
7491 | VM_WARN_ON_ONCE_FOLIO(!memcg, old); | |
29833315 | 7492 | if (!memcg) |
0a31bc97 JW |
7493 | return; |
7494 | ||
44b7a8d3 | 7495 | /* Force-charge the new page. The old one will be freed soon */ |
8dc87c7d MS |
7496 | if (!mem_cgroup_is_root(memcg)) { |
7497 | page_counter_charge(&memcg->memory, nr_pages); | |
7498 | if (do_memsw_account()) | |
7499 | page_counter_charge(&memcg->memsw, nr_pages); | |
7500 | } | |
0a31bc97 | 7501 | |
1a3e1f40 | 7502 | css_get(&memcg->css); |
d21bba2b | 7503 | commit_charge(new, memcg); |
44b7a8d3 | 7504 | |
d93c4130 | 7505 | local_irq_save(flags); |
6e0110c2 | 7506 | mem_cgroup_charge_statistics(memcg, nr_pages); |
d21bba2b | 7507 | memcg_check_events(memcg, folio_nid(new)); |
d93c4130 | 7508 | local_irq_restore(flags); |
0a31bc97 JW |
7509 | } |
7510 | ||
85ce2c51 NP |
7511 | /** |
7512 | * mem_cgroup_migrate - Transfer the memcg data from the old to the new folio. | |
7513 | * @old: Currently circulating folio. | |
7514 | * @new: Replacement folio. | |
7515 | * | |
7516 | * Transfer the memcg data from the old folio to the new folio for migration. | |
7517 | * The old folio's data info will be cleared. Note that the memory counters | |
7518 | * will remain unchanged throughout the process. | |
7519 | * | |
7520 | * Both folios must be locked, @new->mapping must be set up. | |
7521 | */ | |
7522 | void mem_cgroup_migrate(struct folio *old, struct folio *new) | |
7523 | { | |
7524 | struct mem_cgroup *memcg; | |
7525 | ||
7526 | VM_BUG_ON_FOLIO(!folio_test_locked(old), old); | |
7527 | VM_BUG_ON_FOLIO(!folio_test_locked(new), new); | |
7528 | VM_BUG_ON_FOLIO(folio_test_anon(old) != folio_test_anon(new), new); | |
7529 | VM_BUG_ON_FOLIO(folio_nr_pages(old) != folio_nr_pages(new), new); | |
7530 | ||
7531 | if (mem_cgroup_disabled()) | |
7532 | return; | |
7533 | ||
7534 | memcg = folio_memcg(old); | |
8cba9576 NP |
7535 | /* |
7536 | * Note that it is normal to see !memcg for a hugetlb folio. | |
7537 | * For e.g, itt could have been allocated when memory_hugetlb_accounting | |
7538 | * was not selected. | |
7539 | */ | |
7540 | VM_WARN_ON_ONCE_FOLIO(!folio_test_hugetlb(old) && !memcg, old); | |
85ce2c51 NP |
7541 | if (!memcg) |
7542 | return; | |
7543 | ||
7544 | /* Transfer the charge and the css ref */ | |
7545 | commit_charge(new, memcg); | |
7546 | old->memcg_data = 0; | |
7547 | } | |
7548 | ||
ef12947c | 7549 | DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key); |
11092087 JW |
7550 | EXPORT_SYMBOL(memcg_sockets_enabled_key); |
7551 | ||
2d758073 | 7552 | void mem_cgroup_sk_alloc(struct sock *sk) |
11092087 JW |
7553 | { |
7554 | struct mem_cgroup *memcg; | |
7555 | ||
2d758073 JW |
7556 | if (!mem_cgroup_sockets_enabled) |
7557 | return; | |
7558 | ||
e876ecc6 | 7559 | /* Do not associate the sock with unrelated interrupted task's memcg. */ |
086f694a | 7560 | if (!in_task()) |
e876ecc6 SB |
7561 | return; |
7562 | ||
11092087 JW |
7563 | rcu_read_lock(); |
7564 | memcg = mem_cgroup_from_task(current); | |
7848ed62 | 7565 | if (mem_cgroup_is_root(memcg)) |
f7e1cb6e | 7566 | goto out; |
0db15298 | 7567 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcpmem_active) |
f7e1cb6e | 7568 | goto out; |
8965aa28 | 7569 | if (css_tryget(&memcg->css)) |
11092087 | 7570 | sk->sk_memcg = memcg; |
f7e1cb6e | 7571 | out: |
11092087 JW |
7572 | rcu_read_unlock(); |
7573 | } | |
11092087 | 7574 | |
2d758073 | 7575 | void mem_cgroup_sk_free(struct sock *sk) |
11092087 | 7576 | { |
2d758073 JW |
7577 | if (sk->sk_memcg) |
7578 | css_put(&sk->sk_memcg->css); | |
11092087 JW |
7579 | } |
7580 | ||
7581 | /** | |
7582 | * mem_cgroup_charge_skmem - charge socket memory | |
7583 | * @memcg: memcg to charge | |
7584 | * @nr_pages: number of pages to charge | |
4b1327be | 7585 | * @gfp_mask: reclaim mode |
11092087 JW |
7586 | * |
7587 | * Charges @nr_pages to @memcg. Returns %true if the charge fit within | |
4b1327be | 7588 | * @memcg's configured limit, %false if it doesn't. |
11092087 | 7589 | */ |
4b1327be WW |
7590 | bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages, |
7591 | gfp_t gfp_mask) | |
11092087 | 7592 | { |
f7e1cb6e | 7593 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 7594 | struct page_counter *fail; |
f7e1cb6e | 7595 | |
0db15298 JW |
7596 | if (page_counter_try_charge(&memcg->tcpmem, nr_pages, &fail)) { |
7597 | memcg->tcpmem_pressure = 0; | |
f7e1cb6e JW |
7598 | return true; |
7599 | } | |
0db15298 | 7600 | memcg->tcpmem_pressure = 1; |
4b1327be WW |
7601 | if (gfp_mask & __GFP_NOFAIL) { |
7602 | page_counter_charge(&memcg->tcpmem, nr_pages); | |
7603 | return true; | |
7604 | } | |
f7e1cb6e | 7605 | return false; |
11092087 | 7606 | } |
d886f4e4 | 7607 | |
4b1327be WW |
7608 | if (try_charge(memcg, gfp_mask, nr_pages) == 0) { |
7609 | mod_memcg_state(memcg, MEMCG_SOCK, nr_pages); | |
f7e1cb6e | 7610 | return true; |
4b1327be | 7611 | } |
f7e1cb6e | 7612 | |
11092087 JW |
7613 | return false; |
7614 | } | |
7615 | ||
7616 | /** | |
7617 | * mem_cgroup_uncharge_skmem - uncharge socket memory | |
b7701a5f MR |
7618 | * @memcg: memcg to uncharge |
7619 | * @nr_pages: number of pages to uncharge | |
11092087 JW |
7620 | */ |
7621 | void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) | |
7622 | { | |
f7e1cb6e | 7623 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 7624 | page_counter_uncharge(&memcg->tcpmem, nr_pages); |
f7e1cb6e JW |
7625 | return; |
7626 | } | |
d886f4e4 | 7627 | |
c9019e9b | 7628 | mod_memcg_state(memcg, MEMCG_SOCK, -nr_pages); |
b2807f07 | 7629 | |
475d0487 | 7630 | refill_stock(memcg, nr_pages); |
11092087 JW |
7631 | } |
7632 | ||
f7e1cb6e JW |
7633 | static int __init cgroup_memory(char *s) |
7634 | { | |
7635 | char *token; | |
7636 | ||
7637 | while ((token = strsep(&s, ",")) != NULL) { | |
7638 | if (!*token) | |
7639 | continue; | |
7640 | if (!strcmp(token, "nosocket")) | |
7641 | cgroup_memory_nosocket = true; | |
04823c83 VD |
7642 | if (!strcmp(token, "nokmem")) |
7643 | cgroup_memory_nokmem = true; | |
b6c1a8af YS |
7644 | if (!strcmp(token, "nobpf")) |
7645 | cgroup_memory_nobpf = true; | |
f7e1cb6e | 7646 | } |
460a79e1 | 7647 | return 1; |
f7e1cb6e JW |
7648 | } |
7649 | __setup("cgroup.memory=", cgroup_memory); | |
11092087 | 7650 | |
2d11085e | 7651 | /* |
1081312f MH |
7652 | * subsys_initcall() for memory controller. |
7653 | * | |
308167fc SAS |
7654 | * Some parts like memcg_hotplug_cpu_dead() have to be initialized from this |
7655 | * context because of lock dependencies (cgroup_lock -> cpu hotplug) but | |
7656 | * basically everything that doesn't depend on a specific mem_cgroup structure | |
7657 | * should be initialized from here. | |
2d11085e MH |
7658 | */ |
7659 | static int __init mem_cgroup_init(void) | |
7660 | { | |
95a045f6 JW |
7661 | int cpu, node; |
7662 | ||
f3344adf MS |
7663 | /* |
7664 | * Currently s32 type (can refer to struct batched_lruvec_stat) is | |
7665 | * used for per-memcg-per-cpu caching of per-node statistics. In order | |
7666 | * to work fine, we should make sure that the overfill threshold can't | |
7667 | * exceed S32_MAX / PAGE_SIZE. | |
7668 | */ | |
7669 | BUILD_BUG_ON(MEMCG_CHARGE_BATCH > S32_MAX / PAGE_SIZE); | |
7670 | ||
308167fc SAS |
7671 | cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL, |
7672 | memcg_hotplug_cpu_dead); | |
95a045f6 JW |
7673 | |
7674 | for_each_possible_cpu(cpu) | |
7675 | INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work, | |
7676 | drain_local_stock); | |
7677 | ||
7678 | for_each_node(node) { | |
7679 | struct mem_cgroup_tree_per_node *rtpn; | |
95a045f6 | 7680 | |
91f0dcce | 7681 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, node); |
95a045f6 | 7682 | |
ef8f2327 | 7683 | rtpn->rb_root = RB_ROOT; |
fa90b2fd | 7684 | rtpn->rb_rightmost = NULL; |
ef8f2327 | 7685 | spin_lock_init(&rtpn->lock); |
95a045f6 JW |
7686 | soft_limit_tree.rb_tree_per_node[node] = rtpn; |
7687 | } | |
7688 | ||
2d11085e MH |
7689 | return 0; |
7690 | } | |
7691 | subsys_initcall(mem_cgroup_init); | |
21afa38e | 7692 | |
e55b9f96 | 7693 | #ifdef CONFIG_SWAP |
358c07fc AB |
7694 | static struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg) |
7695 | { | |
1c2d479a | 7696 | while (!refcount_inc_not_zero(&memcg->id.ref)) { |
358c07fc AB |
7697 | /* |
7698 | * The root cgroup cannot be destroyed, so it's refcount must | |
7699 | * always be >= 1. | |
7700 | */ | |
7848ed62 | 7701 | if (WARN_ON_ONCE(mem_cgroup_is_root(memcg))) { |
358c07fc AB |
7702 | VM_BUG_ON(1); |
7703 | break; | |
7704 | } | |
7705 | memcg = parent_mem_cgroup(memcg); | |
7706 | if (!memcg) | |
7707 | memcg = root_mem_cgroup; | |
7708 | } | |
7709 | return memcg; | |
7710 | } | |
7711 | ||
21afa38e JW |
7712 | /** |
7713 | * mem_cgroup_swapout - transfer a memsw charge to swap | |
3ecb0087 | 7714 | * @folio: folio whose memsw charge to transfer |
21afa38e JW |
7715 | * @entry: swap entry to move the charge to |
7716 | * | |
3ecb0087 | 7717 | * Transfer the memsw charge of @folio to @entry. |
21afa38e | 7718 | */ |
3ecb0087 | 7719 | void mem_cgroup_swapout(struct folio *folio, swp_entry_t entry) |
21afa38e | 7720 | { |
1f47b61f | 7721 | struct mem_cgroup *memcg, *swap_memcg; |
d6810d73 | 7722 | unsigned int nr_entries; |
21afa38e JW |
7723 | unsigned short oldid; |
7724 | ||
3ecb0087 MWO |
7725 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
7726 | VM_BUG_ON_FOLIO(folio_ref_count(folio), folio); | |
21afa38e | 7727 | |
76358ab5 AS |
7728 | if (mem_cgroup_disabled()) |
7729 | return; | |
7730 | ||
b94c4e94 | 7731 | if (!do_memsw_account()) |
21afa38e JW |
7732 | return; |
7733 | ||
3ecb0087 | 7734 | memcg = folio_memcg(folio); |
21afa38e | 7735 | |
3ecb0087 | 7736 | VM_WARN_ON_ONCE_FOLIO(!memcg, folio); |
21afa38e JW |
7737 | if (!memcg) |
7738 | return; | |
7739 | ||
1f47b61f VD |
7740 | /* |
7741 | * In case the memcg owning these pages has been offlined and doesn't | |
7742 | * have an ID allocated to it anymore, charge the closest online | |
7743 | * ancestor for the swap instead and transfer the memory+swap charge. | |
7744 | */ | |
7745 | swap_memcg = mem_cgroup_id_get_online(memcg); | |
3ecb0087 | 7746 | nr_entries = folio_nr_pages(folio); |
d6810d73 HY |
7747 | /* Get references for the tail pages, too */ |
7748 | if (nr_entries > 1) | |
7749 | mem_cgroup_id_get_many(swap_memcg, nr_entries - 1); | |
7750 | oldid = swap_cgroup_record(entry, mem_cgroup_id(swap_memcg), | |
7751 | nr_entries); | |
3ecb0087 | 7752 | VM_BUG_ON_FOLIO(oldid, folio); |
c9019e9b | 7753 | mod_memcg_state(swap_memcg, MEMCG_SWAP, nr_entries); |
21afa38e | 7754 | |
3ecb0087 | 7755 | folio->memcg_data = 0; |
21afa38e JW |
7756 | |
7757 | if (!mem_cgroup_is_root(memcg)) | |
d6810d73 | 7758 | page_counter_uncharge(&memcg->memory, nr_entries); |
21afa38e | 7759 | |
b25806dc | 7760 | if (memcg != swap_memcg) { |
1f47b61f | 7761 | if (!mem_cgroup_is_root(swap_memcg)) |
d6810d73 HY |
7762 | page_counter_charge(&swap_memcg->memsw, nr_entries); |
7763 | page_counter_uncharge(&memcg->memsw, nr_entries); | |
1f47b61f VD |
7764 | } |
7765 | ||
ce9ce665 SAS |
7766 | /* |
7767 | * Interrupts should be disabled here because the caller holds the | |
b93b0163 | 7768 | * i_pages lock which is taken with interrupts-off. It is |
ce9ce665 | 7769 | * important here to have the interrupts disabled because it is the |
b93b0163 | 7770 | * only synchronisation we have for updating the per-CPU variables. |
ce9ce665 | 7771 | */ |
be3e67b5 | 7772 | memcg_stats_lock(); |
6e0110c2 | 7773 | mem_cgroup_charge_statistics(memcg, -nr_entries); |
be3e67b5 | 7774 | memcg_stats_unlock(); |
3ecb0087 | 7775 | memcg_check_events(memcg, folio_nid(folio)); |
73f576c0 | 7776 | |
1a3e1f40 | 7777 | css_put(&memcg->css); |
21afa38e JW |
7778 | } |
7779 | ||
38d8b4e6 | 7780 | /** |
e2e3fdc7 MWO |
7781 | * __mem_cgroup_try_charge_swap - try charging swap space for a folio |
7782 | * @folio: folio being added to swap | |
37e84351 VD |
7783 | * @entry: swap entry to charge |
7784 | * | |
e2e3fdc7 | 7785 | * Try to charge @folio's memcg for the swap space at @entry. |
37e84351 VD |
7786 | * |
7787 | * Returns 0 on success, -ENOMEM on failure. | |
7788 | */ | |
e2e3fdc7 | 7789 | int __mem_cgroup_try_charge_swap(struct folio *folio, swp_entry_t entry) |
37e84351 | 7790 | { |
e2e3fdc7 | 7791 | unsigned int nr_pages = folio_nr_pages(folio); |
37e84351 | 7792 | struct page_counter *counter; |
38d8b4e6 | 7793 | struct mem_cgroup *memcg; |
37e84351 VD |
7794 | unsigned short oldid; |
7795 | ||
b94c4e94 | 7796 | if (do_memsw_account()) |
37e84351 VD |
7797 | return 0; |
7798 | ||
e2e3fdc7 | 7799 | memcg = folio_memcg(folio); |
37e84351 | 7800 | |
e2e3fdc7 | 7801 | VM_WARN_ON_ONCE_FOLIO(!memcg, folio); |
37e84351 VD |
7802 | if (!memcg) |
7803 | return 0; | |
7804 | ||
f3a53a3a TH |
7805 | if (!entry.val) { |
7806 | memcg_memory_event(memcg, MEMCG_SWAP_FAIL); | |
bb98f2c5 | 7807 | return 0; |
f3a53a3a | 7808 | } |
bb98f2c5 | 7809 | |
1f47b61f VD |
7810 | memcg = mem_cgroup_id_get_online(memcg); |
7811 | ||
b25806dc | 7812 | if (!mem_cgroup_is_root(memcg) && |
38d8b4e6 | 7813 | !page_counter_try_charge(&memcg->swap, nr_pages, &counter)) { |
f3a53a3a TH |
7814 | memcg_memory_event(memcg, MEMCG_SWAP_MAX); |
7815 | memcg_memory_event(memcg, MEMCG_SWAP_FAIL); | |
1f47b61f | 7816 | mem_cgroup_id_put(memcg); |
37e84351 | 7817 | return -ENOMEM; |
1f47b61f | 7818 | } |
37e84351 | 7819 | |
38d8b4e6 HY |
7820 | /* Get references for the tail pages, too */ |
7821 | if (nr_pages > 1) | |
7822 | mem_cgroup_id_get_many(memcg, nr_pages - 1); | |
7823 | oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg), nr_pages); | |
e2e3fdc7 | 7824 | VM_BUG_ON_FOLIO(oldid, folio); |
c9019e9b | 7825 | mod_memcg_state(memcg, MEMCG_SWAP, nr_pages); |
37e84351 | 7826 | |
37e84351 VD |
7827 | return 0; |
7828 | } | |
7829 | ||
21afa38e | 7830 | /** |
01c4b28c | 7831 | * __mem_cgroup_uncharge_swap - uncharge swap space |
21afa38e | 7832 | * @entry: swap entry to uncharge |
38d8b4e6 | 7833 | * @nr_pages: the amount of swap space to uncharge |
21afa38e | 7834 | */ |
01c4b28c | 7835 | void __mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages) |
21afa38e JW |
7836 | { |
7837 | struct mem_cgroup *memcg; | |
7838 | unsigned short id; | |
7839 | ||
38d8b4e6 | 7840 | id = swap_cgroup_record(entry, 0, nr_pages); |
21afa38e | 7841 | rcu_read_lock(); |
adbe427b | 7842 | memcg = mem_cgroup_from_id(id); |
21afa38e | 7843 | if (memcg) { |
b25806dc | 7844 | if (!mem_cgroup_is_root(memcg)) { |
b94c4e94 | 7845 | if (do_memsw_account()) |
38d8b4e6 | 7846 | page_counter_uncharge(&memcg->memsw, nr_pages); |
b94c4e94 JW |
7847 | else |
7848 | page_counter_uncharge(&memcg->swap, nr_pages); | |
37e84351 | 7849 | } |
c9019e9b | 7850 | mod_memcg_state(memcg, MEMCG_SWAP, -nr_pages); |
38d8b4e6 | 7851 | mem_cgroup_id_put_many(memcg, nr_pages); |
21afa38e JW |
7852 | } |
7853 | rcu_read_unlock(); | |
7854 | } | |
7855 | ||
d8b38438 VD |
7856 | long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg) |
7857 | { | |
7858 | long nr_swap_pages = get_nr_swap_pages(); | |
7859 | ||
b25806dc | 7860 | if (mem_cgroup_disabled() || do_memsw_account()) |
d8b38438 | 7861 | return nr_swap_pages; |
7848ed62 | 7862 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) |
d8b38438 | 7863 | nr_swap_pages = min_t(long, nr_swap_pages, |
bbec2e15 | 7864 | READ_ONCE(memcg->swap.max) - |
d8b38438 VD |
7865 | page_counter_read(&memcg->swap)); |
7866 | return nr_swap_pages; | |
7867 | } | |
7868 | ||
9202d527 | 7869 | bool mem_cgroup_swap_full(struct folio *folio) |
5ccc5aba VD |
7870 | { |
7871 | struct mem_cgroup *memcg; | |
7872 | ||
9202d527 | 7873 | VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); |
5ccc5aba VD |
7874 | |
7875 | if (vm_swap_full()) | |
7876 | return true; | |
b25806dc | 7877 | if (do_memsw_account()) |
5ccc5aba VD |
7878 | return false; |
7879 | ||
9202d527 | 7880 | memcg = folio_memcg(folio); |
5ccc5aba VD |
7881 | if (!memcg) |
7882 | return false; | |
7883 | ||
7848ed62 | 7884 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) { |
4b82ab4f JK |
7885 | unsigned long usage = page_counter_read(&memcg->swap); |
7886 | ||
7887 | if (usage * 2 >= READ_ONCE(memcg->swap.high) || | |
7888 | usage * 2 >= READ_ONCE(memcg->swap.max)) | |
5ccc5aba | 7889 | return true; |
4b82ab4f | 7890 | } |
5ccc5aba VD |
7891 | |
7892 | return false; | |
7893 | } | |
7894 | ||
eccb52e7 | 7895 | static int __init setup_swap_account(char *s) |
21afa38e | 7896 | { |
b25806dc JW |
7897 | pr_warn_once("The swapaccount= commandline option is deprecated. " |
7898 | "Please report your usecase to linux-mm@kvack.org if you " | |
7899 | "depend on this functionality.\n"); | |
21afa38e JW |
7900 | return 1; |
7901 | } | |
eccb52e7 | 7902 | __setup("swapaccount=", setup_swap_account); |
21afa38e | 7903 | |
37e84351 VD |
7904 | static u64 swap_current_read(struct cgroup_subsys_state *css, |
7905 | struct cftype *cft) | |
7906 | { | |
7907 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
7908 | ||
7909 | return (u64)page_counter_read(&memcg->swap) * PAGE_SIZE; | |
7910 | } | |
7911 | ||
e0e0b412 LD |
7912 | static u64 swap_peak_read(struct cgroup_subsys_state *css, |
7913 | struct cftype *cft) | |
7914 | { | |
7915 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
7916 | ||
7917 | return (u64)memcg->swap.watermark * PAGE_SIZE; | |
7918 | } | |
7919 | ||
4b82ab4f JK |
7920 | static int swap_high_show(struct seq_file *m, void *v) |
7921 | { | |
7922 | return seq_puts_memcg_tunable(m, | |
7923 | READ_ONCE(mem_cgroup_from_seq(m)->swap.high)); | |
7924 | } | |
7925 | ||
7926 | static ssize_t swap_high_write(struct kernfs_open_file *of, | |
7927 | char *buf, size_t nbytes, loff_t off) | |
7928 | { | |
7929 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
7930 | unsigned long high; | |
7931 | int err; | |
7932 | ||
7933 | buf = strstrip(buf); | |
7934 | err = page_counter_memparse(buf, "max", &high); | |
7935 | if (err) | |
7936 | return err; | |
7937 | ||
7938 | page_counter_set_high(&memcg->swap, high); | |
7939 | ||
7940 | return nbytes; | |
7941 | } | |
7942 | ||
37e84351 VD |
7943 | static int swap_max_show(struct seq_file *m, void *v) |
7944 | { | |
677dc973 CD |
7945 | return seq_puts_memcg_tunable(m, |
7946 | READ_ONCE(mem_cgroup_from_seq(m)->swap.max)); | |
37e84351 VD |
7947 | } |
7948 | ||
7949 | static ssize_t swap_max_write(struct kernfs_open_file *of, | |
7950 | char *buf, size_t nbytes, loff_t off) | |
7951 | { | |
7952 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
7953 | unsigned long max; | |
7954 | int err; | |
7955 | ||
7956 | buf = strstrip(buf); | |
7957 | err = page_counter_memparse(buf, "max", &max); | |
7958 | if (err) | |
7959 | return err; | |
7960 | ||
be09102b | 7961 | xchg(&memcg->swap.max, max); |
37e84351 VD |
7962 | |
7963 | return nbytes; | |
7964 | } | |
7965 | ||
f3a53a3a TH |
7966 | static int swap_events_show(struct seq_file *m, void *v) |
7967 | { | |
aa9694bb | 7968 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
f3a53a3a | 7969 | |
4b82ab4f JK |
7970 | seq_printf(m, "high %lu\n", |
7971 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_HIGH])); | |
f3a53a3a TH |
7972 | seq_printf(m, "max %lu\n", |
7973 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_MAX])); | |
7974 | seq_printf(m, "fail %lu\n", | |
7975 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_FAIL])); | |
7976 | ||
7977 | return 0; | |
7978 | } | |
7979 | ||
37e84351 VD |
7980 | static struct cftype swap_files[] = { |
7981 | { | |
7982 | .name = "swap.current", | |
7983 | .flags = CFTYPE_NOT_ON_ROOT, | |
7984 | .read_u64 = swap_current_read, | |
7985 | }, | |
4b82ab4f JK |
7986 | { |
7987 | .name = "swap.high", | |
7988 | .flags = CFTYPE_NOT_ON_ROOT, | |
7989 | .seq_show = swap_high_show, | |
7990 | .write = swap_high_write, | |
7991 | }, | |
37e84351 VD |
7992 | { |
7993 | .name = "swap.max", | |
7994 | .flags = CFTYPE_NOT_ON_ROOT, | |
7995 | .seq_show = swap_max_show, | |
7996 | .write = swap_max_write, | |
7997 | }, | |
e0e0b412 LD |
7998 | { |
7999 | .name = "swap.peak", | |
8000 | .flags = CFTYPE_NOT_ON_ROOT, | |
8001 | .read_u64 = swap_peak_read, | |
8002 | }, | |
f3a53a3a TH |
8003 | { |
8004 | .name = "swap.events", | |
8005 | .flags = CFTYPE_NOT_ON_ROOT, | |
8006 | .file_offset = offsetof(struct mem_cgroup, swap_events_file), | |
8007 | .seq_show = swap_events_show, | |
8008 | }, | |
37e84351 VD |
8009 | { } /* terminate */ |
8010 | }; | |
8011 | ||
eccb52e7 | 8012 | static struct cftype memsw_files[] = { |
21afa38e JW |
8013 | { |
8014 | .name = "memsw.usage_in_bytes", | |
8015 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
8016 | .read_u64 = mem_cgroup_read_u64, | |
8017 | }, | |
8018 | { | |
8019 | .name = "memsw.max_usage_in_bytes", | |
8020 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
8021 | .write = mem_cgroup_reset, | |
8022 | .read_u64 = mem_cgroup_read_u64, | |
8023 | }, | |
8024 | { | |
8025 | .name = "memsw.limit_in_bytes", | |
8026 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
8027 | .write = mem_cgroup_write, | |
8028 | .read_u64 = mem_cgroup_read_u64, | |
8029 | }, | |
8030 | { | |
8031 | .name = "memsw.failcnt", | |
8032 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
8033 | .write = mem_cgroup_reset, | |
8034 | .read_u64 = mem_cgroup_read_u64, | |
8035 | }, | |
8036 | { }, /* terminate */ | |
8037 | }; | |
8038 | ||
f4840ccf JW |
8039 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
8040 | /** | |
8041 | * obj_cgroup_may_zswap - check if this cgroup can zswap | |
8042 | * @objcg: the object cgroup | |
8043 | * | |
8044 | * Check if the hierarchical zswap limit has been reached. | |
8045 | * | |
8046 | * This doesn't check for specific headroom, and it is not atomic | |
8047 | * either. But with zswap, the size of the allocation is only known | |
be16dd76 | 8048 | * once compression has occurred, and this optimistic pre-check avoids |
f4840ccf JW |
8049 | * spending cycles on compression when there is already no room left |
8050 | * or zswap is disabled altogether somewhere in the hierarchy. | |
8051 | */ | |
8052 | bool obj_cgroup_may_zswap(struct obj_cgroup *objcg) | |
8053 | { | |
8054 | struct mem_cgroup *memcg, *original_memcg; | |
8055 | bool ret = true; | |
8056 | ||
8057 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
8058 | return true; | |
8059 | ||
8060 | original_memcg = get_mem_cgroup_from_objcg(objcg); | |
7848ed62 | 8061 | for (memcg = original_memcg; !mem_cgroup_is_root(memcg); |
f4840ccf JW |
8062 | memcg = parent_mem_cgroup(memcg)) { |
8063 | unsigned long max = READ_ONCE(memcg->zswap_max); | |
8064 | unsigned long pages; | |
8065 | ||
8066 | if (max == PAGE_COUNTER_MAX) | |
8067 | continue; | |
8068 | if (max == 0) { | |
8069 | ret = false; | |
8070 | break; | |
8071 | } | |
8072 | ||
8073 | cgroup_rstat_flush(memcg->css.cgroup); | |
8074 | pages = memcg_page_state(memcg, MEMCG_ZSWAP_B) / PAGE_SIZE; | |
8075 | if (pages < max) | |
8076 | continue; | |
8077 | ret = false; | |
8078 | break; | |
8079 | } | |
8080 | mem_cgroup_put(original_memcg); | |
8081 | return ret; | |
8082 | } | |
8083 | ||
8084 | /** | |
8085 | * obj_cgroup_charge_zswap - charge compression backend memory | |
8086 | * @objcg: the object cgroup | |
8087 | * @size: size of compressed object | |
8088 | * | |
3a1060c2 | 8089 | * This forces the charge after obj_cgroup_may_zswap() allowed |
f4840ccf JW |
8090 | * compression and storage in zwap for this cgroup to go ahead. |
8091 | */ | |
8092 | void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size) | |
8093 | { | |
8094 | struct mem_cgroup *memcg; | |
8095 | ||
8096 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
8097 | return; | |
8098 | ||
8099 | VM_WARN_ON_ONCE(!(current->flags & PF_MEMALLOC)); | |
8100 | ||
8101 | /* PF_MEMALLOC context, charging must succeed */ | |
8102 | if (obj_cgroup_charge(objcg, GFP_KERNEL, size)) | |
8103 | VM_WARN_ON_ONCE(1); | |
8104 | ||
8105 | rcu_read_lock(); | |
8106 | memcg = obj_cgroup_memcg(objcg); | |
8107 | mod_memcg_state(memcg, MEMCG_ZSWAP_B, size); | |
8108 | mod_memcg_state(memcg, MEMCG_ZSWAPPED, 1); | |
8109 | rcu_read_unlock(); | |
8110 | } | |
8111 | ||
8112 | /** | |
8113 | * obj_cgroup_uncharge_zswap - uncharge compression backend memory | |
8114 | * @objcg: the object cgroup | |
8115 | * @size: size of compressed object | |
8116 | * | |
8117 | * Uncharges zswap memory on page in. | |
8118 | */ | |
8119 | void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size) | |
8120 | { | |
8121 | struct mem_cgroup *memcg; | |
8122 | ||
8123 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
8124 | return; | |
8125 | ||
8126 | obj_cgroup_uncharge(objcg, size); | |
8127 | ||
8128 | rcu_read_lock(); | |
8129 | memcg = obj_cgroup_memcg(objcg); | |
8130 | mod_memcg_state(memcg, MEMCG_ZSWAP_B, -size); | |
8131 | mod_memcg_state(memcg, MEMCG_ZSWAPPED, -1); | |
8132 | rcu_read_unlock(); | |
8133 | } | |
8134 | ||
8135 | static u64 zswap_current_read(struct cgroup_subsys_state *css, | |
8136 | struct cftype *cft) | |
8137 | { | |
8138 | cgroup_rstat_flush(css->cgroup); | |
8139 | return memcg_page_state(mem_cgroup_from_css(css), MEMCG_ZSWAP_B); | |
8140 | } | |
8141 | ||
8142 | static int zswap_max_show(struct seq_file *m, void *v) | |
8143 | { | |
8144 | return seq_puts_memcg_tunable(m, | |
8145 | READ_ONCE(mem_cgroup_from_seq(m)->zswap_max)); | |
8146 | } | |
8147 | ||
8148 | static ssize_t zswap_max_write(struct kernfs_open_file *of, | |
8149 | char *buf, size_t nbytes, loff_t off) | |
8150 | { | |
8151 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
8152 | unsigned long max; | |
8153 | int err; | |
8154 | ||
8155 | buf = strstrip(buf); | |
8156 | err = page_counter_memparse(buf, "max", &max); | |
8157 | if (err) | |
8158 | return err; | |
8159 | ||
8160 | xchg(&memcg->zswap_max, max); | |
8161 | ||
8162 | return nbytes; | |
8163 | } | |
8164 | ||
8165 | static struct cftype zswap_files[] = { | |
8166 | { | |
8167 | .name = "zswap.current", | |
8168 | .flags = CFTYPE_NOT_ON_ROOT, | |
8169 | .read_u64 = zswap_current_read, | |
8170 | }, | |
8171 | { | |
8172 | .name = "zswap.max", | |
8173 | .flags = CFTYPE_NOT_ON_ROOT, | |
8174 | .seq_show = zswap_max_show, | |
8175 | .write = zswap_max_write, | |
8176 | }, | |
8177 | { } /* terminate */ | |
8178 | }; | |
8179 | #endif /* CONFIG_MEMCG_KMEM && CONFIG_ZSWAP */ | |
8180 | ||
21afa38e JW |
8181 | static int __init mem_cgroup_swap_init(void) |
8182 | { | |
2d1c4980 | 8183 | if (mem_cgroup_disabled()) |
eccb52e7 JW |
8184 | return 0; |
8185 | ||
8186 | WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, swap_files)); | |
8187 | WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, memsw_files)); | |
f4840ccf JW |
8188 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
8189 | WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, zswap_files)); | |
8190 | #endif | |
21afa38e JW |
8191 | return 0; |
8192 | } | |
b25806dc | 8193 | subsys_initcall(mem_cgroup_swap_init); |
21afa38e | 8194 | |
e55b9f96 | 8195 | #endif /* CONFIG_SWAP */ |