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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 | ||
84c07d11 | 252 | #ifdef CONFIG_MEMCG_KMEM |
0764db9b | 253 | static DEFINE_SPINLOCK(objcg_lock); |
bf4f0599 | 254 | |
4d5c8aed RG |
255 | bool mem_cgroup_kmem_disabled(void) |
256 | { | |
257 | return cgroup_memory_nokmem; | |
258 | } | |
259 | ||
f1286fae MS |
260 | static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, |
261 | unsigned int nr_pages); | |
c1a660de | 262 | |
bf4f0599 RG |
263 | static void obj_cgroup_release(struct percpu_ref *ref) |
264 | { | |
265 | struct obj_cgroup *objcg = container_of(ref, struct obj_cgroup, refcnt); | |
bf4f0599 RG |
266 | unsigned int nr_bytes; |
267 | unsigned int nr_pages; | |
268 | unsigned long flags; | |
269 | ||
270 | /* | |
271 | * At this point all allocated objects are freed, and | |
272 | * objcg->nr_charged_bytes can't have an arbitrary byte value. | |
273 | * However, it can be PAGE_SIZE or (x * PAGE_SIZE). | |
274 | * | |
275 | * The following sequence can lead to it: | |
276 | * 1) CPU0: objcg == stock->cached_objcg | |
277 | * 2) CPU1: we do a small allocation (e.g. 92 bytes), | |
278 | * PAGE_SIZE bytes are charged | |
279 | * 3) CPU1: a process from another memcg is allocating something, | |
280 | * the stock if flushed, | |
281 | * objcg->nr_charged_bytes = PAGE_SIZE - 92 | |
282 | * 5) CPU0: we do release this object, | |
283 | * 92 bytes are added to stock->nr_bytes | |
284 | * 6) CPU0: stock is flushed, | |
285 | * 92 bytes are added to objcg->nr_charged_bytes | |
286 | * | |
287 | * In the result, nr_charged_bytes == PAGE_SIZE. | |
288 | * This page will be uncharged in obj_cgroup_release(). | |
289 | */ | |
290 | nr_bytes = atomic_read(&objcg->nr_charged_bytes); | |
291 | WARN_ON_ONCE(nr_bytes & (PAGE_SIZE - 1)); | |
292 | nr_pages = nr_bytes >> PAGE_SHIFT; | |
293 | ||
bf4f0599 | 294 | if (nr_pages) |
f1286fae | 295 | obj_cgroup_uncharge_pages(objcg, nr_pages); |
271dd6b1 | 296 | |
0764db9b | 297 | spin_lock_irqsave(&objcg_lock, flags); |
bf4f0599 | 298 | list_del(&objcg->list); |
0764db9b | 299 | spin_unlock_irqrestore(&objcg_lock, flags); |
bf4f0599 RG |
300 | |
301 | percpu_ref_exit(ref); | |
302 | kfree_rcu(objcg, rcu); | |
303 | } | |
304 | ||
305 | static struct obj_cgroup *obj_cgroup_alloc(void) | |
306 | { | |
307 | struct obj_cgroup *objcg; | |
308 | int ret; | |
309 | ||
310 | objcg = kzalloc(sizeof(struct obj_cgroup), GFP_KERNEL); | |
311 | if (!objcg) | |
312 | return NULL; | |
313 | ||
314 | ret = percpu_ref_init(&objcg->refcnt, obj_cgroup_release, 0, | |
315 | GFP_KERNEL); | |
316 | if (ret) { | |
317 | kfree(objcg); | |
318 | return NULL; | |
319 | } | |
320 | INIT_LIST_HEAD(&objcg->list); | |
321 | return objcg; | |
322 | } | |
323 | ||
324 | static void memcg_reparent_objcgs(struct mem_cgroup *memcg, | |
325 | struct mem_cgroup *parent) | |
326 | { | |
327 | struct obj_cgroup *objcg, *iter; | |
328 | ||
329 | objcg = rcu_replace_pointer(memcg->objcg, NULL, true); | |
330 | ||
0764db9b | 331 | spin_lock_irq(&objcg_lock); |
bf4f0599 | 332 | |
9838354e MS |
333 | /* 1) Ready to reparent active objcg. */ |
334 | list_add(&objcg->list, &memcg->objcg_list); | |
335 | /* 2) Reparent active objcg and already reparented objcgs to parent. */ | |
336 | list_for_each_entry(iter, &memcg->objcg_list, list) | |
337 | WRITE_ONCE(iter->memcg, parent); | |
338 | /* 3) Move already reparented objcgs to the parent's list */ | |
bf4f0599 RG |
339 | list_splice(&memcg->objcg_list, &parent->objcg_list); |
340 | ||
0764db9b | 341 | spin_unlock_irq(&objcg_lock); |
bf4f0599 RG |
342 | |
343 | percpu_ref_kill(&objcg->refcnt); | |
344 | } | |
345 | ||
d7f25f8a GC |
346 | /* |
347 | * A lot of the calls to the cache allocation functions are expected to be | |
272911a4 | 348 | * inlined by the compiler. Since the calls to memcg_slab_pre_alloc_hook() are |
d7f25f8a GC |
349 | * conditional to this static branch, we'll have to allow modules that does |
350 | * kmem_cache_alloc and the such to see this symbol as well | |
351 | */ | |
f7a449f7 RG |
352 | DEFINE_STATIC_KEY_FALSE(memcg_kmem_online_key); |
353 | EXPORT_SYMBOL(memcg_kmem_online_key); | |
b6c1a8af YS |
354 | |
355 | DEFINE_STATIC_KEY_FALSE(memcg_bpf_enabled_key); | |
356 | EXPORT_SYMBOL(memcg_bpf_enabled_key); | |
0a432dcb | 357 | #endif |
17cc4dfe | 358 | |
ad7fa852 | 359 | /** |
75376c6f MWO |
360 | * mem_cgroup_css_from_folio - css of the memcg associated with a folio |
361 | * @folio: folio of interest | |
ad7fa852 TH |
362 | * |
363 | * If memcg is bound to the default hierarchy, css of the memcg associated | |
75376c6f | 364 | * with @folio is returned. The returned css remains associated with @folio |
ad7fa852 TH |
365 | * until it is released. |
366 | * | |
367 | * If memcg is bound to a traditional hierarchy, the css of root_mem_cgroup | |
368 | * is returned. | |
ad7fa852 | 369 | */ |
75376c6f | 370 | struct cgroup_subsys_state *mem_cgroup_css_from_folio(struct folio *folio) |
ad7fa852 | 371 | { |
75376c6f | 372 | struct mem_cgroup *memcg = folio_memcg(folio); |
ad7fa852 | 373 | |
9e10a130 | 374 | if (!memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
ad7fa852 TH |
375 | memcg = root_mem_cgroup; |
376 | ||
ad7fa852 TH |
377 | return &memcg->css; |
378 | } | |
379 | ||
2fc04524 VD |
380 | /** |
381 | * page_cgroup_ino - return inode number of the memcg a page is charged to | |
382 | * @page: the page | |
383 | * | |
384 | * Look up the closest online ancestor of the memory cgroup @page is charged to | |
385 | * and return its inode number or 0 if @page is not charged to any cgroup. It | |
386 | * is safe to call this function without holding a reference to @page. | |
387 | * | |
388 | * Note, this function is inherently racy, because there is nothing to prevent | |
389 | * the cgroup inode from getting torn down and potentially reallocated a moment | |
390 | * after page_cgroup_ino() returns, so it only should be used by callers that | |
391 | * do not care (such as procfs interfaces). | |
392 | */ | |
393 | ino_t page_cgroup_ino(struct page *page) | |
394 | { | |
395 | struct mem_cgroup *memcg; | |
396 | unsigned long ino = 0; | |
397 | ||
398 | rcu_read_lock(); | |
ec342603 YA |
399 | /* page_folio() is racy here, but the entire function is racy anyway */ |
400 | memcg = folio_memcg_check(page_folio(page)); | |
286e04b8 | 401 | |
2fc04524 VD |
402 | while (memcg && !(memcg->css.flags & CSS_ONLINE)) |
403 | memcg = parent_mem_cgroup(memcg); | |
404 | if (memcg) | |
405 | ino = cgroup_ino(memcg->css.cgroup); | |
406 | rcu_read_unlock(); | |
407 | return ino; | |
408 | } | |
409 | ||
ef8f2327 MG |
410 | static void __mem_cgroup_insert_exceeded(struct mem_cgroup_per_node *mz, |
411 | struct mem_cgroup_tree_per_node *mctz, | |
3e32cb2e | 412 | unsigned long new_usage_in_excess) |
bb4cc1a8 AM |
413 | { |
414 | struct rb_node **p = &mctz->rb_root.rb_node; | |
415 | struct rb_node *parent = NULL; | |
ef8f2327 | 416 | struct mem_cgroup_per_node *mz_node; |
fa90b2fd | 417 | bool rightmost = true; |
bb4cc1a8 AM |
418 | |
419 | if (mz->on_tree) | |
420 | return; | |
421 | ||
422 | mz->usage_in_excess = new_usage_in_excess; | |
423 | if (!mz->usage_in_excess) | |
424 | return; | |
425 | while (*p) { | |
426 | parent = *p; | |
ef8f2327 | 427 | mz_node = rb_entry(parent, struct mem_cgroup_per_node, |
bb4cc1a8 | 428 | tree_node); |
fa90b2fd | 429 | if (mz->usage_in_excess < mz_node->usage_in_excess) { |
bb4cc1a8 | 430 | p = &(*p)->rb_left; |
fa90b2fd | 431 | rightmost = false; |
378876b0 | 432 | } else { |
bb4cc1a8 | 433 | p = &(*p)->rb_right; |
378876b0 | 434 | } |
bb4cc1a8 | 435 | } |
fa90b2fd DB |
436 | |
437 | if (rightmost) | |
438 | mctz->rb_rightmost = &mz->tree_node; | |
439 | ||
bb4cc1a8 AM |
440 | rb_link_node(&mz->tree_node, parent, p); |
441 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
442 | mz->on_tree = true; | |
443 | } | |
444 | ||
ef8f2327 MG |
445 | static void __mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz, |
446 | struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 AM |
447 | { |
448 | if (!mz->on_tree) | |
449 | return; | |
fa90b2fd DB |
450 | |
451 | if (&mz->tree_node == mctz->rb_rightmost) | |
452 | mctz->rb_rightmost = rb_prev(&mz->tree_node); | |
453 | ||
bb4cc1a8 AM |
454 | rb_erase(&mz->tree_node, &mctz->rb_root); |
455 | mz->on_tree = false; | |
456 | } | |
457 | ||
ef8f2327 MG |
458 | static void mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz, |
459 | struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 460 | { |
0a31bc97 JW |
461 | unsigned long flags; |
462 | ||
463 | spin_lock_irqsave(&mctz->lock, flags); | |
cf2c8127 | 464 | __mem_cgroup_remove_exceeded(mz, mctz); |
0a31bc97 | 465 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
466 | } |
467 | ||
3e32cb2e JW |
468 | static unsigned long soft_limit_excess(struct mem_cgroup *memcg) |
469 | { | |
470 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
4db0c3c2 | 471 | unsigned long soft_limit = READ_ONCE(memcg->soft_limit); |
3e32cb2e JW |
472 | unsigned long excess = 0; |
473 | ||
474 | if (nr_pages > soft_limit) | |
475 | excess = nr_pages - soft_limit; | |
476 | ||
477 | return excess; | |
478 | } | |
bb4cc1a8 | 479 | |
658b69c9 | 480 | static void mem_cgroup_update_tree(struct mem_cgroup *memcg, int nid) |
bb4cc1a8 | 481 | { |
3e32cb2e | 482 | unsigned long excess; |
ef8f2327 MG |
483 | struct mem_cgroup_per_node *mz; |
484 | struct mem_cgroup_tree_per_node *mctz; | |
bb4cc1a8 | 485 | |
e4dde56c | 486 | if (lru_gen_enabled()) { |
36c7b4db | 487 | if (soft_limit_excess(memcg)) |
5c7e7a0d | 488 | lru_gen_soft_reclaim(memcg, nid); |
e4dde56c YZ |
489 | return; |
490 | } | |
491 | ||
2ab082ba | 492 | mctz = soft_limit_tree.rb_tree_per_node[nid]; |
bfc7228b LD |
493 | if (!mctz) |
494 | return; | |
bb4cc1a8 AM |
495 | /* |
496 | * Necessary to update all ancestors when hierarchy is used. | |
497 | * because their event counter is not touched. | |
498 | */ | |
499 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
658b69c9 | 500 | mz = memcg->nodeinfo[nid]; |
3e32cb2e | 501 | excess = soft_limit_excess(memcg); |
bb4cc1a8 AM |
502 | /* |
503 | * We have to update the tree if mz is on RB-tree or | |
504 | * mem is over its softlimit. | |
505 | */ | |
506 | if (excess || mz->on_tree) { | |
0a31bc97 JW |
507 | unsigned long flags; |
508 | ||
509 | spin_lock_irqsave(&mctz->lock, flags); | |
bb4cc1a8 AM |
510 | /* if on-tree, remove it */ |
511 | if (mz->on_tree) | |
cf2c8127 | 512 | __mem_cgroup_remove_exceeded(mz, mctz); |
bb4cc1a8 AM |
513 | /* |
514 | * Insert again. mz->usage_in_excess will be updated. | |
515 | * If excess is 0, no tree ops. | |
516 | */ | |
cf2c8127 | 517 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 518 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
519 | } |
520 | } | |
521 | } | |
522 | ||
523 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) | |
524 | { | |
ef8f2327 MG |
525 | struct mem_cgroup_tree_per_node *mctz; |
526 | struct mem_cgroup_per_node *mz; | |
527 | int nid; | |
bb4cc1a8 | 528 | |
e231875b | 529 | for_each_node(nid) { |
a3747b53 | 530 | mz = memcg->nodeinfo[nid]; |
2ab082ba | 531 | mctz = soft_limit_tree.rb_tree_per_node[nid]; |
bfc7228b LD |
532 | if (mctz) |
533 | mem_cgroup_remove_exceeded(mz, mctz); | |
bb4cc1a8 AM |
534 | } |
535 | } | |
536 | ||
ef8f2327 MG |
537 | static struct mem_cgroup_per_node * |
538 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 539 | { |
ef8f2327 | 540 | struct mem_cgroup_per_node *mz; |
bb4cc1a8 AM |
541 | |
542 | retry: | |
543 | mz = NULL; | |
fa90b2fd | 544 | if (!mctz->rb_rightmost) |
bb4cc1a8 AM |
545 | goto done; /* Nothing to reclaim from */ |
546 | ||
fa90b2fd DB |
547 | mz = rb_entry(mctz->rb_rightmost, |
548 | struct mem_cgroup_per_node, tree_node); | |
bb4cc1a8 AM |
549 | /* |
550 | * Remove the node now but someone else can add it back, | |
551 | * we will to add it back at the end of reclaim to its correct | |
552 | * position in the tree. | |
553 | */ | |
cf2c8127 | 554 | __mem_cgroup_remove_exceeded(mz, mctz); |
3e32cb2e | 555 | if (!soft_limit_excess(mz->memcg) || |
8965aa28 | 556 | !css_tryget(&mz->memcg->css)) |
bb4cc1a8 AM |
557 | goto retry; |
558 | done: | |
559 | return mz; | |
560 | } | |
561 | ||
ef8f2327 MG |
562 | static struct mem_cgroup_per_node * |
563 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 564 | { |
ef8f2327 | 565 | struct mem_cgroup_per_node *mz; |
bb4cc1a8 | 566 | |
0a31bc97 | 567 | spin_lock_irq(&mctz->lock); |
bb4cc1a8 | 568 | mz = __mem_cgroup_largest_soft_limit_node(mctz); |
0a31bc97 | 569 | spin_unlock_irq(&mctz->lock); |
bb4cc1a8 AM |
570 | return mz; |
571 | } | |
572 | ||
11192d9c SB |
573 | /* |
574 | * memcg and lruvec stats flushing | |
575 | * | |
576 | * Many codepaths leading to stats update or read are performance sensitive and | |
577 | * adding stats flushing in such codepaths is not desirable. So, to optimize the | |
578 | * flushing the kernel does: | |
579 | * | |
580 | * 1) Periodically and asynchronously flush the stats every 2 seconds to not let | |
581 | * rstat update tree grow unbounded. | |
582 | * | |
583 | * 2) Flush the stats synchronously on reader side only when there are more than | |
584 | * (MEMCG_CHARGE_BATCH * nr_cpus) update events. Though this optimization | |
585 | * will let stats be out of sync by atmost (MEMCG_CHARGE_BATCH * nr_cpus) but | |
586 | * only for 2 seconds due to (1). | |
587 | */ | |
588 | static void flush_memcg_stats_dwork(struct work_struct *w); | |
589 | static DECLARE_DEFERRABLE_WORK(stats_flush_dwork, flush_memcg_stats_dwork); | |
11192d9c | 590 | static DEFINE_PER_CPU(unsigned int, stats_updates); |
3cd9992b | 591 | static atomic_t stats_flush_ongoing = ATOMIC_INIT(0); |
11192d9c | 592 | static atomic_t stats_flush_threshold = ATOMIC_INIT(0); |
9b301615 SB |
593 | static u64 flush_next_time; |
594 | ||
595 | #define FLUSH_TIME (2UL*HZ) | |
11192d9c | 596 | |
be3e67b5 SAS |
597 | /* |
598 | * Accessors to ensure that preemption is disabled on PREEMPT_RT because it can | |
599 | * not rely on this as part of an acquired spinlock_t lock. These functions are | |
600 | * never used in hardirq context on PREEMPT_RT and therefore disabling preemtion | |
601 | * is sufficient. | |
602 | */ | |
603 | static void memcg_stats_lock(void) | |
604 | { | |
e575d401 TG |
605 | preempt_disable_nested(); |
606 | VM_WARN_ON_IRQS_ENABLED(); | |
be3e67b5 SAS |
607 | } |
608 | ||
609 | static void __memcg_stats_lock(void) | |
610 | { | |
e575d401 | 611 | preempt_disable_nested(); |
be3e67b5 SAS |
612 | } |
613 | ||
614 | static void memcg_stats_unlock(void) | |
615 | { | |
e575d401 | 616 | preempt_enable_nested(); |
be3e67b5 SAS |
617 | } |
618 | ||
5b3be698 | 619 | static inline void memcg_rstat_updated(struct mem_cgroup *memcg, int val) |
11192d9c | 620 | { |
5b3be698 SB |
621 | unsigned int x; |
622 | ||
f9d911ca YA |
623 | if (!val) |
624 | return; | |
625 | ||
11192d9c | 626 | cgroup_rstat_updated(memcg->css.cgroup, smp_processor_id()); |
5b3be698 SB |
627 | |
628 | x = __this_cpu_add_return(stats_updates, abs(val)); | |
629 | if (x > MEMCG_CHARGE_BATCH) { | |
873f64b7 JS |
630 | /* |
631 | * If stats_flush_threshold exceeds the threshold | |
632 | * (>num_online_cpus()), cgroup stats update will be triggered | |
633 | * in __mem_cgroup_flush_stats(). Increasing this var further | |
634 | * is redundant and simply adds overhead in atomic update. | |
635 | */ | |
636 | if (atomic_read(&stats_flush_threshold) <= num_online_cpus()) | |
637 | atomic_add(x / MEMCG_CHARGE_BATCH, &stats_flush_threshold); | |
5b3be698 SB |
638 | __this_cpu_write(stats_updates, 0); |
639 | } | |
11192d9c SB |
640 | } |
641 | ||
35822fda | 642 | static void do_flush_stats(void) |
11192d9c | 643 | { |
3cd9992b YA |
644 | /* |
645 | * We always flush the entire tree, so concurrent flushers can just | |
646 | * skip. This avoids a thundering herd problem on the rstat global lock | |
647 | * from memcg flushers (e.g. reclaim, refault, etc). | |
648 | */ | |
649 | if (atomic_read(&stats_flush_ongoing) || | |
650 | atomic_xchg(&stats_flush_ongoing, 1)) | |
11192d9c SB |
651 | return; |
652 | ||
3cd9992b | 653 | WRITE_ONCE(flush_next_time, jiffies_64 + 2*FLUSH_TIME); |
9fad9aee | 654 | |
35822fda | 655 | cgroup_rstat_flush(root_mem_cgroup->css.cgroup); |
9fad9aee | 656 | |
11192d9c | 657 | atomic_set(&stats_flush_threshold, 0); |
3cd9992b | 658 | atomic_set(&stats_flush_ongoing, 0); |
11192d9c SB |
659 | } |
660 | ||
661 | void mem_cgroup_flush_stats(void) | |
662 | { | |
35822fda YA |
663 | if (atomic_read(&stats_flush_threshold) > num_online_cpus()) |
664 | do_flush_stats(); | |
9fad9aee YA |
665 | } |
666 | ||
4009b2f1 | 667 | void mem_cgroup_flush_stats_ratelimited(void) |
9b301615 | 668 | { |
3cd9992b | 669 | if (time_after64(jiffies_64, READ_ONCE(flush_next_time))) |
4009b2f1 | 670 | mem_cgroup_flush_stats(); |
9b301615 SB |
671 | } |
672 | ||
11192d9c SB |
673 | static void flush_memcg_stats_dwork(struct work_struct *w) |
674 | { | |
9fad9aee YA |
675 | /* |
676 | * Always flush here so that flushing in latency-sensitive paths is | |
677 | * as cheap as possible. | |
678 | */ | |
35822fda | 679 | do_flush_stats(); |
9b301615 | 680 | queue_delayed_work(system_unbound_wq, &stats_flush_dwork, FLUSH_TIME); |
11192d9c SB |
681 | } |
682 | ||
d396def5 SB |
683 | /* Subset of vm_event_item to report for memcg event stats */ |
684 | static const unsigned int memcg_vm_event_stat[] = { | |
8278f1c7 SB |
685 | PGPGIN, |
686 | PGPGOUT, | |
d396def5 SB |
687 | PGSCAN_KSWAPD, |
688 | PGSCAN_DIRECT, | |
57e9cc50 | 689 | PGSCAN_KHUGEPAGED, |
d396def5 SB |
690 | PGSTEAL_KSWAPD, |
691 | PGSTEAL_DIRECT, | |
57e9cc50 | 692 | PGSTEAL_KHUGEPAGED, |
d396def5 SB |
693 | PGFAULT, |
694 | PGMAJFAULT, | |
695 | PGREFILL, | |
696 | PGACTIVATE, | |
697 | PGDEACTIVATE, | |
698 | PGLAZYFREE, | |
699 | PGLAZYFREED, | |
700 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) | |
701 | ZSWPIN, | |
702 | ZSWPOUT, | |
703 | #endif | |
704 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
705 | THP_FAULT_ALLOC, | |
706 | THP_COLLAPSE_ALLOC, | |
811244a5 XH |
707 | THP_SWPOUT, |
708 | THP_SWPOUT_FALLBACK, | |
d396def5 SB |
709 | #endif |
710 | }; | |
711 | ||
8278f1c7 SB |
712 | #define NR_MEMCG_EVENTS ARRAY_SIZE(memcg_vm_event_stat) |
713 | static int mem_cgroup_events_index[NR_VM_EVENT_ITEMS] __read_mostly; | |
714 | ||
715 | static void init_memcg_events(void) | |
716 | { | |
717 | int i; | |
718 | ||
719 | for (i = 0; i < NR_MEMCG_EVENTS; ++i) | |
720 | mem_cgroup_events_index[memcg_vm_event_stat[i]] = i + 1; | |
721 | } | |
722 | ||
723 | static inline int memcg_events_index(enum vm_event_item idx) | |
724 | { | |
725 | return mem_cgroup_events_index[idx] - 1; | |
726 | } | |
727 | ||
410f8e82 SB |
728 | struct memcg_vmstats_percpu { |
729 | /* Local (CPU and cgroup) page state & events */ | |
730 | long state[MEMCG_NR_STAT]; | |
8278f1c7 | 731 | unsigned long events[NR_MEMCG_EVENTS]; |
410f8e82 SB |
732 | |
733 | /* Delta calculation for lockless upward propagation */ | |
734 | long state_prev[MEMCG_NR_STAT]; | |
8278f1c7 | 735 | unsigned long events_prev[NR_MEMCG_EVENTS]; |
410f8e82 SB |
736 | |
737 | /* Cgroup1: threshold notifications & softlimit tree updates */ | |
738 | unsigned long nr_page_events; | |
739 | unsigned long targets[MEM_CGROUP_NTARGETS]; | |
740 | }; | |
741 | ||
742 | struct memcg_vmstats { | |
743 | /* Aggregated (CPU and subtree) page state & events */ | |
744 | long state[MEMCG_NR_STAT]; | |
8278f1c7 | 745 | unsigned long events[NR_MEMCG_EVENTS]; |
410f8e82 | 746 | |
f82e6bf9 YA |
747 | /* Non-hierarchical (CPU aggregated) page state & events */ |
748 | long state_local[MEMCG_NR_STAT]; | |
749 | unsigned long events_local[NR_MEMCG_EVENTS]; | |
750 | ||
410f8e82 SB |
751 | /* Pending child counts during tree propagation */ |
752 | long state_pending[MEMCG_NR_STAT]; | |
8278f1c7 | 753 | unsigned long events_pending[NR_MEMCG_EVENTS]; |
410f8e82 SB |
754 | }; |
755 | ||
756 | unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx) | |
757 | { | |
758 | long x = READ_ONCE(memcg->vmstats->state[idx]); | |
759 | #ifdef CONFIG_SMP | |
760 | if (x < 0) | |
761 | x = 0; | |
762 | #endif | |
763 | return x; | |
764 | } | |
765 | ||
db9adbcb JW |
766 | /** |
767 | * __mod_memcg_state - update cgroup memory statistics | |
768 | * @memcg: the memory cgroup | |
769 | * @idx: the stat item - can be enum memcg_stat_item or enum node_stat_item | |
770 | * @val: delta to add to the counter, can be negative | |
771 | */ | |
772 | void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val) | |
773 | { | |
db9adbcb JW |
774 | if (mem_cgroup_disabled()) |
775 | return; | |
776 | ||
2d146aa3 | 777 | __this_cpu_add(memcg->vmstats_percpu->state[idx], val); |
5b3be698 | 778 | memcg_rstat_updated(memcg, val); |
db9adbcb JW |
779 | } |
780 | ||
2d146aa3 | 781 | /* idx can be of type enum memcg_stat_item or node_stat_item. */ |
a18e6e6e JW |
782 | static unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx) |
783 | { | |
f82e6bf9 | 784 | long x = READ_ONCE(memcg->vmstats->state_local[idx]); |
a18e6e6e | 785 | |
a18e6e6e JW |
786 | #ifdef CONFIG_SMP |
787 | if (x < 0) | |
788 | x = 0; | |
789 | #endif | |
790 | return x; | |
791 | } | |
792 | ||
eedc4e5a RG |
793 | void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, |
794 | int val) | |
db9adbcb JW |
795 | { |
796 | struct mem_cgroup_per_node *pn; | |
42a30035 | 797 | struct mem_cgroup *memcg; |
db9adbcb | 798 | |
db9adbcb | 799 | pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec); |
42a30035 | 800 | memcg = pn->memcg; |
db9adbcb | 801 | |
be3e67b5 SAS |
802 | /* |
803 | * The caller from rmap relay on disabled preemption becase they never | |
804 | * update their counter from in-interrupt context. For these two | |
805 | * counters we check that the update is never performed from an | |
806 | * interrupt context while other caller need to have disabled interrupt. | |
807 | */ | |
808 | __memcg_stats_lock(); | |
e575d401 | 809 | if (IS_ENABLED(CONFIG_DEBUG_VM)) { |
be3e67b5 SAS |
810 | switch (idx) { |
811 | case NR_ANON_MAPPED: | |
812 | case NR_FILE_MAPPED: | |
813 | case NR_ANON_THPS: | |
814 | case NR_SHMEM_PMDMAPPED: | |
815 | case NR_FILE_PMDMAPPED: | |
816 | WARN_ON_ONCE(!in_task()); | |
817 | break; | |
818 | default: | |
e575d401 | 819 | VM_WARN_ON_IRQS_ENABLED(); |
be3e67b5 SAS |
820 | } |
821 | } | |
822 | ||
db9adbcb | 823 | /* Update memcg */ |
11192d9c | 824 | __this_cpu_add(memcg->vmstats_percpu->state[idx], val); |
db9adbcb | 825 | |
b4c46484 | 826 | /* Update lruvec */ |
7e1c0d6f | 827 | __this_cpu_add(pn->lruvec_stats_percpu->state[idx], val); |
11192d9c | 828 | |
5b3be698 | 829 | memcg_rstat_updated(memcg, val); |
be3e67b5 | 830 | memcg_stats_unlock(); |
db9adbcb JW |
831 | } |
832 | ||
eedc4e5a RG |
833 | /** |
834 | * __mod_lruvec_state - update lruvec memory statistics | |
835 | * @lruvec: the lruvec | |
836 | * @idx: the stat item | |
837 | * @val: delta to add to the counter, can be negative | |
838 | * | |
839 | * The lruvec is the intersection of the NUMA node and a cgroup. This | |
840 | * function updates the all three counters that are affected by a | |
841 | * change of state at this level: per-node, per-cgroup, per-lruvec. | |
842 | */ | |
843 | void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, | |
844 | int val) | |
845 | { | |
846 | /* Update node */ | |
847 | __mod_node_page_state(lruvec_pgdat(lruvec), idx, val); | |
848 | ||
849 | /* Update memcg and lruvec */ | |
850 | if (!mem_cgroup_disabled()) | |
851 | __mod_memcg_lruvec_state(lruvec, idx, val); | |
852 | } | |
853 | ||
c47d5032 SB |
854 | void __mod_lruvec_page_state(struct page *page, enum node_stat_item idx, |
855 | int val) | |
856 | { | |
857 | struct page *head = compound_head(page); /* rmap on tail pages */ | |
b4e0b68f | 858 | struct mem_cgroup *memcg; |
c47d5032 SB |
859 | pg_data_t *pgdat = page_pgdat(page); |
860 | struct lruvec *lruvec; | |
861 | ||
b4e0b68f MS |
862 | rcu_read_lock(); |
863 | memcg = page_memcg(head); | |
c47d5032 | 864 | /* Untracked pages have no memcg, no lruvec. Update only the node */ |
d635a69d | 865 | if (!memcg) { |
b4e0b68f | 866 | rcu_read_unlock(); |
c47d5032 SB |
867 | __mod_node_page_state(pgdat, idx, val); |
868 | return; | |
869 | } | |
870 | ||
d635a69d | 871 | lruvec = mem_cgroup_lruvec(memcg, pgdat); |
c47d5032 | 872 | __mod_lruvec_state(lruvec, idx, val); |
b4e0b68f | 873 | rcu_read_unlock(); |
c47d5032 | 874 | } |
f0c0c115 | 875 | EXPORT_SYMBOL(__mod_lruvec_page_state); |
c47d5032 | 876 | |
da3ceeff | 877 | void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) |
ec9f0238 | 878 | { |
4f103c63 | 879 | pg_data_t *pgdat = page_pgdat(virt_to_page(p)); |
ec9f0238 RG |
880 | struct mem_cgroup *memcg; |
881 | struct lruvec *lruvec; | |
882 | ||
883 | rcu_read_lock(); | |
fc4db90f | 884 | memcg = mem_cgroup_from_slab_obj(p); |
ec9f0238 | 885 | |
8faeb1ff MS |
886 | /* |
887 | * Untracked pages have no memcg, no lruvec. Update only the | |
888 | * node. If we reparent the slab objects to the root memcg, | |
889 | * when we free the slab object, we need to update the per-memcg | |
890 | * vmstats to keep it correct for the root memcg. | |
891 | */ | |
892 | if (!memcg) { | |
ec9f0238 RG |
893 | __mod_node_page_state(pgdat, idx, val); |
894 | } else { | |
867e5e1d | 895 | lruvec = mem_cgroup_lruvec(memcg, pgdat); |
ec9f0238 RG |
896 | __mod_lruvec_state(lruvec, idx, val); |
897 | } | |
898 | rcu_read_unlock(); | |
899 | } | |
900 | ||
db9adbcb JW |
901 | /** |
902 | * __count_memcg_events - account VM events in a cgroup | |
903 | * @memcg: the memory cgroup | |
904 | * @idx: the event item | |
f0953a1b | 905 | * @count: the number of events that occurred |
db9adbcb JW |
906 | */ |
907 | void __count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx, | |
908 | unsigned long count) | |
909 | { | |
8278f1c7 SB |
910 | int index = memcg_events_index(idx); |
911 | ||
912 | if (mem_cgroup_disabled() || index < 0) | |
db9adbcb JW |
913 | return; |
914 | ||
be3e67b5 | 915 | memcg_stats_lock(); |
8278f1c7 | 916 | __this_cpu_add(memcg->vmstats_percpu->events[index], count); |
5b3be698 | 917 | memcg_rstat_updated(memcg, count); |
be3e67b5 | 918 | memcg_stats_unlock(); |
db9adbcb JW |
919 | } |
920 | ||
42a30035 | 921 | static unsigned long memcg_events(struct mem_cgroup *memcg, int event) |
e9f8974f | 922 | { |
8278f1c7 SB |
923 | int index = memcg_events_index(event); |
924 | ||
925 | if (index < 0) | |
926 | return 0; | |
927 | return READ_ONCE(memcg->vmstats->events[index]); | |
e9f8974f JW |
928 | } |
929 | ||
42a30035 JW |
930 | static unsigned long memcg_events_local(struct mem_cgroup *memcg, int event) |
931 | { | |
8278f1c7 SB |
932 | int index = memcg_events_index(event); |
933 | ||
934 | if (index < 0) | |
935 | return 0; | |
815744d7 | 936 | |
f82e6bf9 | 937 | return READ_ONCE(memcg->vmstats->events_local[index]); |
42a30035 JW |
938 | } |
939 | ||
c0ff4b85 | 940 | static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, |
3fba69a5 | 941 | int nr_pages) |
d52aa412 | 942 | { |
e401f176 KH |
943 | /* pagein of a big page is an event. So, ignore page size */ |
944 | if (nr_pages > 0) | |
c9019e9b | 945 | __count_memcg_events(memcg, PGPGIN, 1); |
3751d604 | 946 | else { |
c9019e9b | 947 | __count_memcg_events(memcg, PGPGOUT, 1); |
3751d604 KH |
948 | nr_pages = -nr_pages; /* for event */ |
949 | } | |
e401f176 | 950 | |
871789d4 | 951 | __this_cpu_add(memcg->vmstats_percpu->nr_page_events, nr_pages); |
6d12e2d8 KH |
952 | } |
953 | ||
f53d7ce3 JW |
954 | static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg, |
955 | enum mem_cgroup_events_target target) | |
7a159cc9 JW |
956 | { |
957 | unsigned long val, next; | |
958 | ||
871789d4 CD |
959 | val = __this_cpu_read(memcg->vmstats_percpu->nr_page_events); |
960 | next = __this_cpu_read(memcg->vmstats_percpu->targets[target]); | |
7a159cc9 | 961 | /* from time_after() in jiffies.h */ |
6a1a8b80 | 962 | if ((long)(next - val) < 0) { |
f53d7ce3 JW |
963 | switch (target) { |
964 | case MEM_CGROUP_TARGET_THRESH: | |
965 | next = val + THRESHOLDS_EVENTS_TARGET; | |
966 | break; | |
bb4cc1a8 AM |
967 | case MEM_CGROUP_TARGET_SOFTLIMIT: |
968 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
969 | break; | |
f53d7ce3 JW |
970 | default: |
971 | break; | |
972 | } | |
871789d4 | 973 | __this_cpu_write(memcg->vmstats_percpu->targets[target], next); |
f53d7ce3 | 974 | return true; |
7a159cc9 | 975 | } |
f53d7ce3 | 976 | return false; |
d2265e6f KH |
977 | } |
978 | ||
979 | /* | |
980 | * Check events in order. | |
981 | * | |
982 | */ | |
8e88bd2d | 983 | static void memcg_check_events(struct mem_cgroup *memcg, int nid) |
d2265e6f | 984 | { |
2343e88d SAS |
985 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) |
986 | return; | |
987 | ||
d2265e6f | 988 | /* threshold event is triggered in finer grain than soft limit */ |
f53d7ce3 JW |
989 | if (unlikely(mem_cgroup_event_ratelimit(memcg, |
990 | MEM_CGROUP_TARGET_THRESH))) { | |
bb4cc1a8 | 991 | bool do_softlimit; |
f53d7ce3 | 992 | |
bb4cc1a8 AM |
993 | do_softlimit = mem_cgroup_event_ratelimit(memcg, |
994 | MEM_CGROUP_TARGET_SOFTLIMIT); | |
c0ff4b85 | 995 | mem_cgroup_threshold(memcg); |
bb4cc1a8 | 996 | if (unlikely(do_softlimit)) |
8e88bd2d | 997 | mem_cgroup_update_tree(memcg, nid); |
0a31bc97 | 998 | } |
d2265e6f KH |
999 | } |
1000 | ||
cf475ad2 | 1001 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 1002 | { |
31a78f23 BS |
1003 | /* |
1004 | * mm_update_next_owner() may clear mm->owner to NULL | |
1005 | * if it races with swapoff, page migration, etc. | |
1006 | * So this can be called with p == NULL. | |
1007 | */ | |
1008 | if (unlikely(!p)) | |
1009 | return NULL; | |
1010 | ||
073219e9 | 1011 | return mem_cgroup_from_css(task_css(p, memory_cgrp_id)); |
78fb7466 | 1012 | } |
33398cf2 | 1013 | EXPORT_SYMBOL(mem_cgroup_from_task); |
78fb7466 | 1014 | |
04f94e3f DS |
1015 | static __always_inline struct mem_cgroup *active_memcg(void) |
1016 | { | |
55a68c82 | 1017 | if (!in_task()) |
04f94e3f DS |
1018 | return this_cpu_read(int_active_memcg); |
1019 | else | |
1020 | return current->active_memcg; | |
1021 | } | |
1022 | ||
d46eb14b SB |
1023 | /** |
1024 | * get_mem_cgroup_from_mm: Obtain a reference on given mm_struct's memcg. | |
1025 | * @mm: mm from which memcg should be extracted. It can be NULL. | |
1026 | * | |
04f94e3f DS |
1027 | * Obtain a reference on mm->memcg and returns it if successful. If mm |
1028 | * is NULL, then the memcg is chosen as follows: | |
1029 | * 1) The active memcg, if set. | |
1030 | * 2) current->mm->memcg, if available | |
1031 | * 3) root memcg | |
1032 | * If mem_cgroup is disabled, NULL is returned. | |
d46eb14b SB |
1033 | */ |
1034 | struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm) | |
54595fe2 | 1035 | { |
d46eb14b SB |
1036 | struct mem_cgroup *memcg; |
1037 | ||
1038 | if (mem_cgroup_disabled()) | |
1039 | return NULL; | |
0b7f569e | 1040 | |
2884b6b7 MS |
1041 | /* |
1042 | * Page cache insertions can happen without an | |
1043 | * actual mm context, e.g. during disk probing | |
1044 | * on boot, loopback IO, acct() writes etc. | |
1045 | * | |
1046 | * No need to css_get on root memcg as the reference | |
1047 | * counting is disabled on the root level in the | |
1048 | * cgroup core. See CSS_NO_REF. | |
1049 | */ | |
04f94e3f DS |
1050 | if (unlikely(!mm)) { |
1051 | memcg = active_memcg(); | |
1052 | if (unlikely(memcg)) { | |
1053 | /* remote memcg must hold a ref */ | |
1054 | css_get(&memcg->css); | |
1055 | return memcg; | |
1056 | } | |
1057 | mm = current->mm; | |
1058 | if (unlikely(!mm)) | |
1059 | return root_mem_cgroup; | |
1060 | } | |
2884b6b7 | 1061 | |
54595fe2 KH |
1062 | rcu_read_lock(); |
1063 | do { | |
2884b6b7 MS |
1064 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); |
1065 | if (unlikely(!memcg)) | |
df381975 | 1066 | memcg = root_mem_cgroup; |
00d484f3 | 1067 | } while (!css_tryget(&memcg->css)); |
54595fe2 | 1068 | rcu_read_unlock(); |
c0ff4b85 | 1069 | return memcg; |
54595fe2 | 1070 | } |
d46eb14b SB |
1071 | EXPORT_SYMBOL(get_mem_cgroup_from_mm); |
1072 | ||
4127c650 RG |
1073 | static __always_inline bool memcg_kmem_bypass(void) |
1074 | { | |
1075 | /* Allow remote memcg charging from any context. */ | |
1076 | if (unlikely(active_memcg())) | |
1077 | return false; | |
1078 | ||
1079 | /* Memcg to charge can't be determined. */ | |
6126891c | 1080 | if (!in_task() || !current->mm || (current->flags & PF_KTHREAD)) |
4127c650 RG |
1081 | return true; |
1082 | ||
1083 | return false; | |
1084 | } | |
1085 | ||
5660048c JW |
1086 | /** |
1087 | * mem_cgroup_iter - iterate over memory cgroup hierarchy | |
1088 | * @root: hierarchy root | |
1089 | * @prev: previously returned memcg, NULL on first invocation | |
1090 | * @reclaim: cookie for shared reclaim walks, NULL for full walks | |
1091 | * | |
1092 | * Returns references to children of the hierarchy below @root, or | |
1093 | * @root itself, or %NULL after a full round-trip. | |
1094 | * | |
1095 | * Caller must pass the return value in @prev on subsequent | |
1096 | * invocations for reference counting, or use mem_cgroup_iter_break() | |
1097 | * to cancel a hierarchy walk before the round-trip is complete. | |
1098 | * | |
05bdc520 ML |
1099 | * Reclaimers can specify a node in @reclaim to divide up the memcgs |
1100 | * in the hierarchy among all concurrent reclaimers operating on the | |
1101 | * same node. | |
5660048c | 1102 | */ |
694fbc0f | 1103 | struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, |
5660048c | 1104 | struct mem_cgroup *prev, |
694fbc0f | 1105 | struct mem_cgroup_reclaim_cookie *reclaim) |
14067bb3 | 1106 | { |
3f649ab7 | 1107 | struct mem_cgroup_reclaim_iter *iter; |
5ac8fb31 | 1108 | struct cgroup_subsys_state *css = NULL; |
9f3a0d09 | 1109 | struct mem_cgroup *memcg = NULL; |
5ac8fb31 | 1110 | struct mem_cgroup *pos = NULL; |
711d3d2c | 1111 | |
694fbc0f AM |
1112 | if (mem_cgroup_disabled()) |
1113 | return NULL; | |
5660048c | 1114 | |
9f3a0d09 JW |
1115 | if (!root) |
1116 | root = root_mem_cgroup; | |
7d74b06f | 1117 | |
542f85f9 | 1118 | rcu_read_lock(); |
5f578161 | 1119 | |
5ac8fb31 | 1120 | if (reclaim) { |
ef8f2327 | 1121 | struct mem_cgroup_per_node *mz; |
5ac8fb31 | 1122 | |
a3747b53 | 1123 | mz = root->nodeinfo[reclaim->pgdat->node_id]; |
9da83f3f | 1124 | iter = &mz->iter; |
5ac8fb31 | 1125 | |
a9320aae WY |
1126 | /* |
1127 | * On start, join the current reclaim iteration cycle. | |
1128 | * Exit when a concurrent walker completes it. | |
1129 | */ | |
1130 | if (!prev) | |
1131 | reclaim->generation = iter->generation; | |
1132 | else if (reclaim->generation != iter->generation) | |
5ac8fb31 JW |
1133 | goto out_unlock; |
1134 | ||
6df38689 | 1135 | while (1) { |
4db0c3c2 | 1136 | pos = READ_ONCE(iter->position); |
6df38689 VD |
1137 | if (!pos || css_tryget(&pos->css)) |
1138 | break; | |
5ac8fb31 | 1139 | /* |
6df38689 VD |
1140 | * css reference reached zero, so iter->position will |
1141 | * be cleared by ->css_released. However, we should not | |
1142 | * rely on this happening soon, because ->css_released | |
1143 | * is called from a work queue, and by busy-waiting we | |
1144 | * might block it. So we clear iter->position right | |
1145 | * away. | |
5ac8fb31 | 1146 | */ |
6df38689 VD |
1147 | (void)cmpxchg(&iter->position, pos, NULL); |
1148 | } | |
89d8330c WY |
1149 | } else if (prev) { |
1150 | pos = prev; | |
5ac8fb31 JW |
1151 | } |
1152 | ||
1153 | if (pos) | |
1154 | css = &pos->css; | |
1155 | ||
1156 | for (;;) { | |
1157 | css = css_next_descendant_pre(css, &root->css); | |
1158 | if (!css) { | |
1159 | /* | |
1160 | * Reclaimers share the hierarchy walk, and a | |
1161 | * new one might jump in right at the end of | |
1162 | * the hierarchy - make sure they see at least | |
1163 | * one group and restart from the beginning. | |
1164 | */ | |
1165 | if (!prev) | |
1166 | continue; | |
1167 | break; | |
527a5ec9 | 1168 | } |
7d74b06f | 1169 | |
5ac8fb31 JW |
1170 | /* |
1171 | * Verify the css and acquire a reference. The root | |
1172 | * is provided by the caller, so we know it's alive | |
1173 | * and kicking, and don't take an extra reference. | |
1174 | */ | |
41555dad WY |
1175 | if (css == &root->css || css_tryget(css)) { |
1176 | memcg = mem_cgroup_from_css(css); | |
0b8f73e1 | 1177 | break; |
41555dad | 1178 | } |
9f3a0d09 | 1179 | } |
5ac8fb31 JW |
1180 | |
1181 | if (reclaim) { | |
5ac8fb31 | 1182 | /* |
6df38689 VD |
1183 | * The position could have already been updated by a competing |
1184 | * thread, so check that the value hasn't changed since we read | |
1185 | * it to avoid reclaiming from the same cgroup twice. | |
5ac8fb31 | 1186 | */ |
6df38689 VD |
1187 | (void)cmpxchg(&iter->position, pos, memcg); |
1188 | ||
5ac8fb31 JW |
1189 | if (pos) |
1190 | css_put(&pos->css); | |
1191 | ||
1192 | if (!memcg) | |
1193 | iter->generation++; | |
9f3a0d09 | 1194 | } |
5ac8fb31 | 1195 | |
542f85f9 MH |
1196 | out_unlock: |
1197 | rcu_read_unlock(); | |
c40046f3 MH |
1198 | if (prev && prev != root) |
1199 | css_put(&prev->css); | |
1200 | ||
9f3a0d09 | 1201 | return memcg; |
14067bb3 | 1202 | } |
7d74b06f | 1203 | |
5660048c JW |
1204 | /** |
1205 | * mem_cgroup_iter_break - abort a hierarchy walk prematurely | |
1206 | * @root: hierarchy root | |
1207 | * @prev: last visited hierarchy member as returned by mem_cgroup_iter() | |
1208 | */ | |
1209 | void mem_cgroup_iter_break(struct mem_cgroup *root, | |
1210 | struct mem_cgroup *prev) | |
9f3a0d09 JW |
1211 | { |
1212 | if (!root) | |
1213 | root = root_mem_cgroup; | |
1214 | if (prev && prev != root) | |
1215 | css_put(&prev->css); | |
1216 | } | |
7d74b06f | 1217 | |
54a83d6b MC |
1218 | static void __invalidate_reclaim_iterators(struct mem_cgroup *from, |
1219 | struct mem_cgroup *dead_memcg) | |
6df38689 | 1220 | { |
6df38689 | 1221 | struct mem_cgroup_reclaim_iter *iter; |
ef8f2327 MG |
1222 | struct mem_cgroup_per_node *mz; |
1223 | int nid; | |
6df38689 | 1224 | |
54a83d6b | 1225 | for_each_node(nid) { |
a3747b53 | 1226 | mz = from->nodeinfo[nid]; |
9da83f3f YS |
1227 | iter = &mz->iter; |
1228 | cmpxchg(&iter->position, dead_memcg, NULL); | |
6df38689 VD |
1229 | } |
1230 | } | |
1231 | ||
54a83d6b MC |
1232 | static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg) |
1233 | { | |
1234 | struct mem_cgroup *memcg = dead_memcg; | |
1235 | struct mem_cgroup *last; | |
1236 | ||
1237 | do { | |
1238 | __invalidate_reclaim_iterators(memcg, dead_memcg); | |
1239 | last = memcg; | |
1240 | } while ((memcg = parent_mem_cgroup(memcg))); | |
1241 | ||
1242 | /* | |
b8dd3ee9 | 1243 | * When cgroup1 non-hierarchy mode is used, |
54a83d6b MC |
1244 | * parent_mem_cgroup() does not walk all the way up to the |
1245 | * cgroup root (root_mem_cgroup). So we have to handle | |
1246 | * dead_memcg from cgroup root separately. | |
1247 | */ | |
7848ed62 | 1248 | if (!mem_cgroup_is_root(last)) |
54a83d6b MC |
1249 | __invalidate_reclaim_iterators(root_mem_cgroup, |
1250 | dead_memcg); | |
1251 | } | |
1252 | ||
7c5f64f8 VD |
1253 | /** |
1254 | * mem_cgroup_scan_tasks - iterate over tasks of a memory cgroup hierarchy | |
1255 | * @memcg: hierarchy root | |
1256 | * @fn: function to call for each task | |
1257 | * @arg: argument passed to @fn | |
1258 | * | |
1259 | * This function iterates over tasks attached to @memcg or to any of its | |
1260 | * descendants and calls @fn for each task. If @fn returns a non-zero | |
025b7799 Z |
1261 | * value, the function breaks the iteration loop. Otherwise, it will iterate |
1262 | * over all tasks and return 0. | |
7c5f64f8 VD |
1263 | * |
1264 | * This function must not be called for the root memory cgroup. | |
1265 | */ | |
025b7799 Z |
1266 | void mem_cgroup_scan_tasks(struct mem_cgroup *memcg, |
1267 | int (*fn)(struct task_struct *, void *), void *arg) | |
7c5f64f8 VD |
1268 | { |
1269 | struct mem_cgroup *iter; | |
1270 | int ret = 0; | |
1271 | ||
7848ed62 | 1272 | BUG_ON(mem_cgroup_is_root(memcg)); |
7c5f64f8 VD |
1273 | |
1274 | for_each_mem_cgroup_tree(iter, memcg) { | |
1275 | struct css_task_iter it; | |
1276 | struct task_struct *task; | |
1277 | ||
f168a9a5 | 1278 | css_task_iter_start(&iter->css, CSS_TASK_ITER_PROCS, &it); |
7c5f64f8 VD |
1279 | while (!ret && (task = css_task_iter_next(&it))) |
1280 | ret = fn(task, arg); | |
1281 | css_task_iter_end(&it); | |
1282 | if (ret) { | |
1283 | mem_cgroup_iter_break(memcg, iter); | |
1284 | break; | |
1285 | } | |
1286 | } | |
7c5f64f8 VD |
1287 | } |
1288 | ||
6168d0da | 1289 | #ifdef CONFIG_DEBUG_VM |
e809c3fe | 1290 | void lruvec_memcg_debug(struct lruvec *lruvec, struct folio *folio) |
6168d0da AS |
1291 | { |
1292 | struct mem_cgroup *memcg; | |
1293 | ||
1294 | if (mem_cgroup_disabled()) | |
1295 | return; | |
1296 | ||
e809c3fe | 1297 | memcg = folio_memcg(folio); |
6168d0da AS |
1298 | |
1299 | if (!memcg) | |
7848ed62 | 1300 | VM_BUG_ON_FOLIO(!mem_cgroup_is_root(lruvec_memcg(lruvec)), folio); |
6168d0da | 1301 | else |
e809c3fe | 1302 | VM_BUG_ON_FOLIO(lruvec_memcg(lruvec) != memcg, folio); |
6168d0da AS |
1303 | } |
1304 | #endif | |
1305 | ||
6168d0da | 1306 | /** |
e809c3fe MWO |
1307 | * folio_lruvec_lock - Lock the lruvec for a folio. |
1308 | * @folio: Pointer to the folio. | |
6168d0da | 1309 | * |
d7e3aba5 | 1310 | * These functions are safe to use under any of the following conditions: |
e809c3fe MWO |
1311 | * - folio locked |
1312 | * - folio_test_lru false | |
1313 | * - folio_memcg_lock() | |
1314 | * - folio frozen (refcount of 0) | |
1315 | * | |
1316 | * Return: The lruvec this folio is on with its lock held. | |
6168d0da | 1317 | */ |
e809c3fe | 1318 | struct lruvec *folio_lruvec_lock(struct folio *folio) |
6168d0da | 1319 | { |
e809c3fe | 1320 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1321 | |
6168d0da | 1322 | spin_lock(&lruvec->lru_lock); |
e809c3fe | 1323 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1324 | |
1325 | return lruvec; | |
1326 | } | |
1327 | ||
e809c3fe MWO |
1328 | /** |
1329 | * folio_lruvec_lock_irq - Lock the lruvec for a folio. | |
1330 | * @folio: Pointer to the folio. | |
1331 | * | |
1332 | * These functions are safe to use under any of the following conditions: | |
1333 | * - folio locked | |
1334 | * - folio_test_lru false | |
1335 | * - folio_memcg_lock() | |
1336 | * - folio frozen (refcount of 0) | |
1337 | * | |
1338 | * Return: The lruvec this folio is on with its lock held and interrupts | |
1339 | * disabled. | |
1340 | */ | |
1341 | struct lruvec *folio_lruvec_lock_irq(struct folio *folio) | |
6168d0da | 1342 | { |
e809c3fe | 1343 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1344 | |
6168d0da | 1345 | spin_lock_irq(&lruvec->lru_lock); |
e809c3fe | 1346 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1347 | |
1348 | return lruvec; | |
1349 | } | |
1350 | ||
e809c3fe MWO |
1351 | /** |
1352 | * folio_lruvec_lock_irqsave - Lock the lruvec for a folio. | |
1353 | * @folio: Pointer to the folio. | |
1354 | * @flags: Pointer to irqsave flags. | |
1355 | * | |
1356 | * These functions are safe to use under any of the following conditions: | |
1357 | * - folio locked | |
1358 | * - folio_test_lru false | |
1359 | * - folio_memcg_lock() | |
1360 | * - folio frozen (refcount of 0) | |
1361 | * | |
1362 | * Return: The lruvec this folio is on with its lock held and interrupts | |
1363 | * disabled. | |
1364 | */ | |
1365 | struct lruvec *folio_lruvec_lock_irqsave(struct folio *folio, | |
1366 | unsigned long *flags) | |
6168d0da | 1367 | { |
e809c3fe | 1368 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1369 | |
6168d0da | 1370 | spin_lock_irqsave(&lruvec->lru_lock, *flags); |
e809c3fe | 1371 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1372 | |
1373 | return lruvec; | |
1374 | } | |
1375 | ||
925b7673 | 1376 | /** |
fa9add64 HD |
1377 | * mem_cgroup_update_lru_size - account for adding or removing an lru page |
1378 | * @lruvec: mem_cgroup per zone lru vector | |
1379 | * @lru: index of lru list the page is sitting on | |
b4536f0c | 1380 | * @zid: zone id of the accounted pages |
fa9add64 | 1381 | * @nr_pages: positive when adding or negative when removing |
925b7673 | 1382 | * |
ca707239 | 1383 | * This function must be called under lru_lock, just before a page is added |
07ca7606 | 1384 | * to or just after a page is removed from an lru list. |
3f58a829 | 1385 | */ |
fa9add64 | 1386 | void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, |
b4536f0c | 1387 | int zid, int nr_pages) |
3f58a829 | 1388 | { |
ef8f2327 | 1389 | struct mem_cgroup_per_node *mz; |
fa9add64 | 1390 | unsigned long *lru_size; |
ca707239 | 1391 | long size; |
3f58a829 MK |
1392 | |
1393 | if (mem_cgroup_disabled()) | |
1394 | return; | |
1395 | ||
ef8f2327 | 1396 | mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); |
b4536f0c | 1397 | lru_size = &mz->lru_zone_size[zid][lru]; |
ca707239 HD |
1398 | |
1399 | if (nr_pages < 0) | |
1400 | *lru_size += nr_pages; | |
1401 | ||
1402 | size = *lru_size; | |
b4536f0c MH |
1403 | if (WARN_ONCE(size < 0, |
1404 | "%s(%p, %d, %d): lru_size %ld\n", | |
1405 | __func__, lruvec, lru, nr_pages, size)) { | |
ca707239 HD |
1406 | VM_BUG_ON(1); |
1407 | *lru_size = 0; | |
1408 | } | |
1409 | ||
1410 | if (nr_pages > 0) | |
1411 | *lru_size += nr_pages; | |
08e552c6 | 1412 | } |
544122e5 | 1413 | |
19942822 | 1414 | /** |
9d11ea9f | 1415 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
dad7557e | 1416 | * @memcg: the memory cgroup |
19942822 | 1417 | * |
9d11ea9f | 1418 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1419 | * pages. |
19942822 | 1420 | */ |
c0ff4b85 | 1421 | static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) |
19942822 | 1422 | { |
3e32cb2e JW |
1423 | unsigned long margin = 0; |
1424 | unsigned long count; | |
1425 | unsigned long limit; | |
9d11ea9f | 1426 | |
3e32cb2e | 1427 | count = page_counter_read(&memcg->memory); |
bbec2e15 | 1428 | limit = READ_ONCE(memcg->memory.max); |
3e32cb2e JW |
1429 | if (count < limit) |
1430 | margin = limit - count; | |
1431 | ||
7941d214 | 1432 | if (do_memsw_account()) { |
3e32cb2e | 1433 | count = page_counter_read(&memcg->memsw); |
bbec2e15 | 1434 | limit = READ_ONCE(memcg->memsw.max); |
1c4448ed | 1435 | if (count < limit) |
3e32cb2e | 1436 | margin = min(margin, limit - count); |
cbedbac3 LR |
1437 | else |
1438 | margin = 0; | |
3e32cb2e JW |
1439 | } |
1440 | ||
1441 | return margin; | |
19942822 JW |
1442 | } |
1443 | ||
32047e2a | 1444 | /* |
bdcbb659 | 1445 | * A routine for checking "mem" is under move_account() or not. |
32047e2a | 1446 | * |
bdcbb659 QH |
1447 | * Checking a cgroup is mc.from or mc.to or under hierarchy of |
1448 | * moving cgroups. This is for waiting at high-memory pressure | |
1449 | * caused by "move". | |
32047e2a | 1450 | */ |
c0ff4b85 | 1451 | static bool mem_cgroup_under_move(struct mem_cgroup *memcg) |
4b534334 | 1452 | { |
2bd9bb20 KH |
1453 | struct mem_cgroup *from; |
1454 | struct mem_cgroup *to; | |
4b534334 | 1455 | bool ret = false; |
2bd9bb20 KH |
1456 | /* |
1457 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1458 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1459 | */ | |
1460 | spin_lock(&mc.lock); | |
1461 | from = mc.from; | |
1462 | to = mc.to; | |
1463 | if (!from) | |
1464 | goto unlock; | |
3e92041d | 1465 | |
2314b42d JW |
1466 | ret = mem_cgroup_is_descendant(from, memcg) || |
1467 | mem_cgroup_is_descendant(to, memcg); | |
2bd9bb20 KH |
1468 | unlock: |
1469 | spin_unlock(&mc.lock); | |
4b534334 KH |
1470 | return ret; |
1471 | } | |
1472 | ||
c0ff4b85 | 1473 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) |
4b534334 KH |
1474 | { |
1475 | if (mc.moving_task && current != mc.moving_task) { | |
c0ff4b85 | 1476 | if (mem_cgroup_under_move(memcg)) { |
4b534334 KH |
1477 | DEFINE_WAIT(wait); |
1478 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1479 | /* moving charge context might have finished. */ | |
1480 | if (mc.moving_task) | |
1481 | schedule(); | |
1482 | finish_wait(&mc.waitq, &wait); | |
1483 | return true; | |
1484 | } | |
1485 | } | |
1486 | return false; | |
1487 | } | |
1488 | ||
5f9a4f4a MS |
1489 | struct memory_stat { |
1490 | const char *name; | |
5f9a4f4a MS |
1491 | unsigned int idx; |
1492 | }; | |
1493 | ||
57b2847d | 1494 | static const struct memory_stat memory_stats[] = { |
fff66b79 MS |
1495 | { "anon", NR_ANON_MAPPED }, |
1496 | { "file", NR_FILE_PAGES }, | |
a8c49af3 | 1497 | { "kernel", MEMCG_KMEM }, |
fff66b79 MS |
1498 | { "kernel_stack", NR_KERNEL_STACK_KB }, |
1499 | { "pagetables", NR_PAGETABLE }, | |
ebc97a52 | 1500 | { "sec_pagetables", NR_SECONDARY_PAGETABLE }, |
fff66b79 MS |
1501 | { "percpu", MEMCG_PERCPU_B }, |
1502 | { "sock", MEMCG_SOCK }, | |
4e5aa1f4 | 1503 | { "vmalloc", MEMCG_VMALLOC }, |
fff66b79 | 1504 | { "shmem", NR_SHMEM }, |
f4840ccf JW |
1505 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
1506 | { "zswap", MEMCG_ZSWAP_B }, | |
1507 | { "zswapped", MEMCG_ZSWAPPED }, | |
1508 | #endif | |
fff66b79 MS |
1509 | { "file_mapped", NR_FILE_MAPPED }, |
1510 | { "file_dirty", NR_FILE_DIRTY }, | |
1511 | { "file_writeback", NR_WRITEBACK }, | |
b6038942 SB |
1512 | #ifdef CONFIG_SWAP |
1513 | { "swapcached", NR_SWAPCACHE }, | |
1514 | #endif | |
5f9a4f4a | 1515 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
fff66b79 MS |
1516 | { "anon_thp", NR_ANON_THPS }, |
1517 | { "file_thp", NR_FILE_THPS }, | |
1518 | { "shmem_thp", NR_SHMEM_THPS }, | |
5f9a4f4a | 1519 | #endif |
fff66b79 MS |
1520 | { "inactive_anon", NR_INACTIVE_ANON }, |
1521 | { "active_anon", NR_ACTIVE_ANON }, | |
1522 | { "inactive_file", NR_INACTIVE_FILE }, | |
1523 | { "active_file", NR_ACTIVE_FILE }, | |
1524 | { "unevictable", NR_UNEVICTABLE }, | |
1525 | { "slab_reclaimable", NR_SLAB_RECLAIMABLE_B }, | |
1526 | { "slab_unreclaimable", NR_SLAB_UNRECLAIMABLE_B }, | |
5f9a4f4a MS |
1527 | |
1528 | /* The memory events */ | |
fff66b79 MS |
1529 | { "workingset_refault_anon", WORKINGSET_REFAULT_ANON }, |
1530 | { "workingset_refault_file", WORKINGSET_REFAULT_FILE }, | |
1531 | { "workingset_activate_anon", WORKINGSET_ACTIVATE_ANON }, | |
1532 | { "workingset_activate_file", WORKINGSET_ACTIVATE_FILE }, | |
1533 | { "workingset_restore_anon", WORKINGSET_RESTORE_ANON }, | |
1534 | { "workingset_restore_file", WORKINGSET_RESTORE_FILE }, | |
1535 | { "workingset_nodereclaim", WORKINGSET_NODERECLAIM }, | |
5f9a4f4a MS |
1536 | }; |
1537 | ||
fff66b79 MS |
1538 | /* Translate stat items to the correct unit for memory.stat output */ |
1539 | static int memcg_page_state_unit(int item) | |
1540 | { | |
1541 | switch (item) { | |
1542 | case MEMCG_PERCPU_B: | |
f4840ccf | 1543 | case MEMCG_ZSWAP_B: |
fff66b79 MS |
1544 | case NR_SLAB_RECLAIMABLE_B: |
1545 | case NR_SLAB_UNRECLAIMABLE_B: | |
1546 | case WORKINGSET_REFAULT_ANON: | |
1547 | case WORKINGSET_REFAULT_FILE: | |
1548 | case WORKINGSET_ACTIVATE_ANON: | |
1549 | case WORKINGSET_ACTIVATE_FILE: | |
1550 | case WORKINGSET_RESTORE_ANON: | |
1551 | case WORKINGSET_RESTORE_FILE: | |
1552 | case WORKINGSET_NODERECLAIM: | |
1553 | return 1; | |
1554 | case NR_KERNEL_STACK_KB: | |
1555 | return SZ_1K; | |
1556 | default: | |
1557 | return PAGE_SIZE; | |
1558 | } | |
1559 | } | |
1560 | ||
1561 | static inline unsigned long memcg_page_state_output(struct mem_cgroup *memcg, | |
1562 | int item) | |
1563 | { | |
1564 | return memcg_page_state(memcg, item) * memcg_page_state_unit(item); | |
1565 | } | |
1566 | ||
dddb44ff | 1567 | static void memcg_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) |
c8713d0b | 1568 | { |
c8713d0b | 1569 | int i; |
71cd3113 | 1570 | |
c8713d0b JW |
1571 | /* |
1572 | * Provide statistics on the state of the memory subsystem as | |
1573 | * well as cumulative event counters that show past behavior. | |
1574 | * | |
1575 | * This list is ordered following a combination of these gradients: | |
1576 | * 1) generic big picture -> specifics and details | |
1577 | * 2) reflecting userspace activity -> reflecting kernel heuristics | |
1578 | * | |
1579 | * Current memory state: | |
1580 | */ | |
fd25a9e0 | 1581 | mem_cgroup_flush_stats(); |
c8713d0b | 1582 | |
5f9a4f4a MS |
1583 | for (i = 0; i < ARRAY_SIZE(memory_stats); i++) { |
1584 | u64 size; | |
c8713d0b | 1585 | |
fff66b79 | 1586 | size = memcg_page_state_output(memcg, memory_stats[i].idx); |
5b42360c | 1587 | seq_buf_printf(s, "%s %llu\n", memory_stats[i].name, size); |
c8713d0b | 1588 | |
5f9a4f4a | 1589 | if (unlikely(memory_stats[i].idx == NR_SLAB_UNRECLAIMABLE_B)) { |
fff66b79 MS |
1590 | size += memcg_page_state_output(memcg, |
1591 | NR_SLAB_RECLAIMABLE_B); | |
5b42360c | 1592 | seq_buf_printf(s, "slab %llu\n", size); |
5f9a4f4a MS |
1593 | } |
1594 | } | |
c8713d0b JW |
1595 | |
1596 | /* Accumulated memory events */ | |
5b42360c | 1597 | seq_buf_printf(s, "pgscan %lu\n", |
c8713d0b | 1598 | memcg_events(memcg, PGSCAN_KSWAPD) + |
57e9cc50 JW |
1599 | memcg_events(memcg, PGSCAN_DIRECT) + |
1600 | memcg_events(memcg, PGSCAN_KHUGEPAGED)); | |
5b42360c | 1601 | seq_buf_printf(s, "pgsteal %lu\n", |
c8713d0b | 1602 | memcg_events(memcg, PGSTEAL_KSWAPD) + |
57e9cc50 JW |
1603 | memcg_events(memcg, PGSTEAL_DIRECT) + |
1604 | memcg_events(memcg, PGSTEAL_KHUGEPAGED)); | |
c8713d0b | 1605 | |
8278f1c7 SB |
1606 | for (i = 0; i < ARRAY_SIZE(memcg_vm_event_stat); i++) { |
1607 | if (memcg_vm_event_stat[i] == PGPGIN || | |
1608 | memcg_vm_event_stat[i] == PGPGOUT) | |
1609 | continue; | |
1610 | ||
5b42360c | 1611 | seq_buf_printf(s, "%s %lu\n", |
673520f8 QZ |
1612 | vm_event_name(memcg_vm_event_stat[i]), |
1613 | memcg_events(memcg, memcg_vm_event_stat[i])); | |
8278f1c7 | 1614 | } |
c8713d0b JW |
1615 | |
1616 | /* The above should easily fit into one page */ | |
5b42360c | 1617 | WARN_ON_ONCE(seq_buf_has_overflowed(s)); |
c8713d0b | 1618 | } |
71cd3113 | 1619 | |
dddb44ff YA |
1620 | static void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s); |
1621 | ||
1622 | static void memory_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) | |
1623 | { | |
1624 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
1625 | memcg_stat_format(memcg, s); | |
1626 | else | |
1627 | memcg1_stat_format(memcg, s); | |
1628 | WARN_ON_ONCE(seq_buf_has_overflowed(s)); | |
1629 | } | |
1630 | ||
e222432b | 1631 | /** |
f0c867d9 | 1632 | * mem_cgroup_print_oom_context: Print OOM information relevant to |
1633 | * memory controller. | |
e222432b BS |
1634 | * @memcg: The memory cgroup that went over limit |
1635 | * @p: Task that is going to be killed | |
1636 | * | |
1637 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1638 | * enabled | |
1639 | */ | |
f0c867d9 | 1640 | void mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p) |
e222432b | 1641 | { |
e222432b BS |
1642 | rcu_read_lock(); |
1643 | ||
f0c867d9 | 1644 | if (memcg) { |
1645 | pr_cont(",oom_memcg="); | |
1646 | pr_cont_cgroup_path(memcg->css.cgroup); | |
1647 | } else | |
1648 | pr_cont(",global_oom"); | |
2415b9f5 | 1649 | if (p) { |
f0c867d9 | 1650 | pr_cont(",task_memcg="); |
2415b9f5 | 1651 | pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id)); |
2415b9f5 | 1652 | } |
e222432b | 1653 | rcu_read_unlock(); |
f0c867d9 | 1654 | } |
1655 | ||
1656 | /** | |
1657 | * mem_cgroup_print_oom_meminfo: Print OOM memory information relevant to | |
1658 | * memory controller. | |
1659 | * @memcg: The memory cgroup that went over limit | |
1660 | */ | |
1661 | void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg) | |
1662 | { | |
68aaee14 TH |
1663 | /* Use static buffer, for the caller is holding oom_lock. */ |
1664 | static char buf[PAGE_SIZE]; | |
5b42360c | 1665 | struct seq_buf s; |
68aaee14 TH |
1666 | |
1667 | lockdep_assert_held(&oom_lock); | |
e222432b | 1668 | |
3e32cb2e JW |
1669 | pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n", |
1670 | K((u64)page_counter_read(&memcg->memory)), | |
15b42562 | 1671 | K((u64)READ_ONCE(memcg->memory.max)), memcg->memory.failcnt); |
c8713d0b JW |
1672 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
1673 | pr_info("swap: usage %llukB, limit %llukB, failcnt %lu\n", | |
1674 | K((u64)page_counter_read(&memcg->swap)), | |
32d087cd | 1675 | K((u64)READ_ONCE(memcg->swap.max)), memcg->swap.failcnt); |
c8713d0b JW |
1676 | else { |
1677 | pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n", | |
1678 | K((u64)page_counter_read(&memcg->memsw)), | |
1679 | K((u64)memcg->memsw.max), memcg->memsw.failcnt); | |
1680 | pr_info("kmem: usage %llukB, limit %llukB, failcnt %lu\n", | |
1681 | K((u64)page_counter_read(&memcg->kmem)), | |
1682 | K((u64)memcg->kmem.max), memcg->kmem.failcnt); | |
58cf188e | 1683 | } |
c8713d0b JW |
1684 | |
1685 | pr_info("Memory cgroup stats for "); | |
1686 | pr_cont_cgroup_path(memcg->css.cgroup); | |
1687 | pr_cont(":"); | |
5b42360c YA |
1688 | seq_buf_init(&s, buf, sizeof(buf)); |
1689 | memory_stat_format(memcg, &s); | |
1690 | seq_buf_do_printk(&s, KERN_INFO); | |
e222432b BS |
1691 | } |
1692 | ||
a63d83f4 DR |
1693 | /* |
1694 | * Return the memory (and swap, if configured) limit for a memcg. | |
1695 | */ | |
bbec2e15 | 1696 | unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg) |
a63d83f4 | 1697 | { |
8d387a5f WL |
1698 | unsigned long max = READ_ONCE(memcg->memory.max); |
1699 | ||
b94c4e94 | 1700 | if (do_memsw_account()) { |
8d387a5f WL |
1701 | if (mem_cgroup_swappiness(memcg)) { |
1702 | /* Calculate swap excess capacity from memsw limit */ | |
1703 | unsigned long swap = READ_ONCE(memcg->memsw.max) - max; | |
1704 | ||
1705 | max += min(swap, (unsigned long)total_swap_pages); | |
1706 | } | |
b94c4e94 JW |
1707 | } else { |
1708 | if (mem_cgroup_swappiness(memcg)) | |
1709 | max += min(READ_ONCE(memcg->swap.max), | |
1710 | (unsigned long)total_swap_pages); | |
9a5a8f19 | 1711 | } |
bbec2e15 | 1712 | return max; |
a63d83f4 DR |
1713 | } |
1714 | ||
9783aa99 CD |
1715 | unsigned long mem_cgroup_size(struct mem_cgroup *memcg) |
1716 | { | |
1717 | return page_counter_read(&memcg->memory); | |
1718 | } | |
1719 | ||
b6e6edcf | 1720 | static bool mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, |
19965460 | 1721 | int order) |
9cbb78bb | 1722 | { |
6e0fc46d DR |
1723 | struct oom_control oc = { |
1724 | .zonelist = NULL, | |
1725 | .nodemask = NULL, | |
2a966b77 | 1726 | .memcg = memcg, |
6e0fc46d DR |
1727 | .gfp_mask = gfp_mask, |
1728 | .order = order, | |
6e0fc46d | 1729 | }; |
1378b37d | 1730 | bool ret = true; |
9cbb78bb | 1731 | |
7775face TH |
1732 | if (mutex_lock_killable(&oom_lock)) |
1733 | return true; | |
1378b37d YS |
1734 | |
1735 | if (mem_cgroup_margin(memcg) >= (1 << order)) | |
1736 | goto unlock; | |
1737 | ||
7775face TH |
1738 | /* |
1739 | * A few threads which were not waiting at mutex_lock_killable() can | |
1740 | * fail to bail out. Therefore, check again after holding oom_lock. | |
1741 | */ | |
a4ebf1b6 | 1742 | ret = task_is_dying() || out_of_memory(&oc); |
1378b37d YS |
1743 | |
1744 | unlock: | |
dc56401f | 1745 | mutex_unlock(&oom_lock); |
7c5f64f8 | 1746 | return ret; |
9cbb78bb DR |
1747 | } |
1748 | ||
0608f43d | 1749 | static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, |
ef8f2327 | 1750 | pg_data_t *pgdat, |
0608f43d AM |
1751 | gfp_t gfp_mask, |
1752 | unsigned long *total_scanned) | |
1753 | { | |
1754 | struct mem_cgroup *victim = NULL; | |
1755 | int total = 0; | |
1756 | int loop = 0; | |
1757 | unsigned long excess; | |
1758 | unsigned long nr_scanned; | |
1759 | struct mem_cgroup_reclaim_cookie reclaim = { | |
ef8f2327 | 1760 | .pgdat = pgdat, |
0608f43d AM |
1761 | }; |
1762 | ||
3e32cb2e | 1763 | excess = soft_limit_excess(root_memcg); |
0608f43d AM |
1764 | |
1765 | while (1) { | |
1766 | victim = mem_cgroup_iter(root_memcg, victim, &reclaim); | |
1767 | if (!victim) { | |
1768 | loop++; | |
1769 | if (loop >= 2) { | |
1770 | /* | |
1771 | * If we have not been able to reclaim | |
1772 | * anything, it might because there are | |
1773 | * no reclaimable pages under this hierarchy | |
1774 | */ | |
1775 | if (!total) | |
1776 | break; | |
1777 | /* | |
1778 | * We want to do more targeted reclaim. | |
1779 | * excess >> 2 is not to excessive so as to | |
1780 | * reclaim too much, nor too less that we keep | |
1781 | * coming back to reclaim from this cgroup | |
1782 | */ | |
1783 | if (total >= (excess >> 2) || | |
1784 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) | |
1785 | break; | |
1786 | } | |
1787 | continue; | |
1788 | } | |
a9dd0a83 | 1789 | total += mem_cgroup_shrink_node(victim, gfp_mask, false, |
ef8f2327 | 1790 | pgdat, &nr_scanned); |
0608f43d | 1791 | *total_scanned += nr_scanned; |
3e32cb2e | 1792 | if (!soft_limit_excess(root_memcg)) |
0608f43d | 1793 | break; |
6d61ef40 | 1794 | } |
0608f43d AM |
1795 | mem_cgroup_iter_break(root_memcg, victim); |
1796 | return total; | |
6d61ef40 BS |
1797 | } |
1798 | ||
0056f4e6 JW |
1799 | #ifdef CONFIG_LOCKDEP |
1800 | static struct lockdep_map memcg_oom_lock_dep_map = { | |
1801 | .name = "memcg_oom_lock", | |
1802 | }; | |
1803 | #endif | |
1804 | ||
fb2a6fc5 JW |
1805 | static DEFINE_SPINLOCK(memcg_oom_lock); |
1806 | ||
867578cb KH |
1807 | /* |
1808 | * Check OOM-Killer is already running under our hierarchy. | |
1809 | * If someone is running, return false. | |
1810 | */ | |
fb2a6fc5 | 1811 | static bool mem_cgroup_oom_trylock(struct mem_cgroup *memcg) |
867578cb | 1812 | { |
79dfdacc | 1813 | struct mem_cgroup *iter, *failed = NULL; |
a636b327 | 1814 | |
fb2a6fc5 JW |
1815 | spin_lock(&memcg_oom_lock); |
1816 | ||
9f3a0d09 | 1817 | for_each_mem_cgroup_tree(iter, memcg) { |
23751be0 | 1818 | if (iter->oom_lock) { |
79dfdacc MH |
1819 | /* |
1820 | * this subtree of our hierarchy is already locked | |
1821 | * so we cannot give a lock. | |
1822 | */ | |
79dfdacc | 1823 | failed = iter; |
9f3a0d09 JW |
1824 | mem_cgroup_iter_break(memcg, iter); |
1825 | break; | |
23751be0 JW |
1826 | } else |
1827 | iter->oom_lock = true; | |
7d74b06f | 1828 | } |
867578cb | 1829 | |
fb2a6fc5 JW |
1830 | if (failed) { |
1831 | /* | |
1832 | * OK, we failed to lock the whole subtree so we have | |
1833 | * to clean up what we set up to the failing subtree | |
1834 | */ | |
1835 | for_each_mem_cgroup_tree(iter, memcg) { | |
1836 | if (iter == failed) { | |
1837 | mem_cgroup_iter_break(memcg, iter); | |
1838 | break; | |
1839 | } | |
1840 | iter->oom_lock = false; | |
79dfdacc | 1841 | } |
0056f4e6 JW |
1842 | } else |
1843 | mutex_acquire(&memcg_oom_lock_dep_map, 0, 1, _RET_IP_); | |
fb2a6fc5 JW |
1844 | |
1845 | spin_unlock(&memcg_oom_lock); | |
1846 | ||
1847 | return !failed; | |
a636b327 | 1848 | } |
0b7f569e | 1849 | |
fb2a6fc5 | 1850 | static void mem_cgroup_oom_unlock(struct mem_cgroup *memcg) |
0b7f569e | 1851 | { |
7d74b06f KH |
1852 | struct mem_cgroup *iter; |
1853 | ||
fb2a6fc5 | 1854 | spin_lock(&memcg_oom_lock); |
5facae4f | 1855 | mutex_release(&memcg_oom_lock_dep_map, _RET_IP_); |
c0ff4b85 | 1856 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc | 1857 | iter->oom_lock = false; |
fb2a6fc5 | 1858 | spin_unlock(&memcg_oom_lock); |
79dfdacc MH |
1859 | } |
1860 | ||
c0ff4b85 | 1861 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1862 | { |
1863 | struct mem_cgroup *iter; | |
1864 | ||
c2b42d3c | 1865 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1866 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1867 | iter->under_oom++; |
1868 | spin_unlock(&memcg_oom_lock); | |
79dfdacc MH |
1869 | } |
1870 | ||
c0ff4b85 | 1871 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1872 | { |
1873 | struct mem_cgroup *iter; | |
1874 | ||
867578cb | 1875 | /* |
f0953a1b | 1876 | * Be careful about under_oom underflows because a child memcg |
7a52d4d8 | 1877 | * could have been added after mem_cgroup_mark_under_oom. |
867578cb | 1878 | */ |
c2b42d3c | 1879 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1880 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1881 | if (iter->under_oom > 0) |
1882 | iter->under_oom--; | |
1883 | spin_unlock(&memcg_oom_lock); | |
0b7f569e KH |
1884 | } |
1885 | ||
867578cb KH |
1886 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1887 | ||
dc98df5a | 1888 | struct oom_wait_info { |
d79154bb | 1889 | struct mem_cgroup *memcg; |
ac6424b9 | 1890 | wait_queue_entry_t wait; |
dc98df5a KH |
1891 | }; |
1892 | ||
ac6424b9 | 1893 | static int memcg_oom_wake_function(wait_queue_entry_t *wait, |
dc98df5a KH |
1894 | unsigned mode, int sync, void *arg) |
1895 | { | |
d79154bb HD |
1896 | struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg; |
1897 | struct mem_cgroup *oom_wait_memcg; | |
dc98df5a KH |
1898 | struct oom_wait_info *oom_wait_info; |
1899 | ||
1900 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
d79154bb | 1901 | oom_wait_memcg = oom_wait_info->memcg; |
dc98df5a | 1902 | |
2314b42d JW |
1903 | if (!mem_cgroup_is_descendant(wake_memcg, oom_wait_memcg) && |
1904 | !mem_cgroup_is_descendant(oom_wait_memcg, wake_memcg)) | |
dc98df5a | 1905 | return 0; |
dc98df5a KH |
1906 | return autoremove_wake_function(wait, mode, sync, arg); |
1907 | } | |
1908 | ||
c0ff4b85 | 1909 | static void memcg_oom_recover(struct mem_cgroup *memcg) |
3c11ecf4 | 1910 | { |
c2b42d3c TH |
1911 | /* |
1912 | * For the following lockless ->under_oom test, the only required | |
1913 | * guarantee is that it must see the state asserted by an OOM when | |
1914 | * this function is called as a result of userland actions | |
1915 | * triggered by the notification of the OOM. This is trivially | |
1916 | * achieved by invoking mem_cgroup_mark_under_oom() before | |
1917 | * triggering notification. | |
1918 | */ | |
1919 | if (memcg && memcg->under_oom) | |
f4b90b70 | 1920 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg); |
3c11ecf4 KH |
1921 | } |
1922 | ||
becdf89d SB |
1923 | /* |
1924 | * Returns true if successfully killed one or more processes. Though in some | |
1925 | * corner cases it can return true even without killing any process. | |
1926 | */ | |
1927 | static bool mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order) | |
0b7f569e | 1928 | { |
becdf89d | 1929 | bool locked, ret; |
7056d3a3 | 1930 | |
29ef680a | 1931 | if (order > PAGE_ALLOC_COSTLY_ORDER) |
becdf89d | 1932 | return false; |
29ef680a | 1933 | |
7a1adfdd RG |
1934 | memcg_memory_event(memcg, MEMCG_OOM); |
1935 | ||
867578cb | 1936 | /* |
49426420 JW |
1937 | * We are in the middle of the charge context here, so we |
1938 | * don't want to block when potentially sitting on a callstack | |
1939 | * that holds all kinds of filesystem and mm locks. | |
1940 | * | |
29ef680a MH |
1941 | * cgroup1 allows disabling the OOM killer and waiting for outside |
1942 | * handling until the charge can succeed; remember the context and put | |
1943 | * the task to sleep at the end of the page fault when all locks are | |
1944 | * released. | |
49426420 | 1945 | * |
29ef680a MH |
1946 | * On the other hand, in-kernel OOM killer allows for an async victim |
1947 | * memory reclaim (oom_reaper) and that means that we are not solely | |
1948 | * relying on the oom victim to make a forward progress and we can | |
1949 | * invoke the oom killer here. | |
1950 | * | |
1951 | * Please note that mem_cgroup_out_of_memory might fail to find a | |
1952 | * victim and then we have to bail out from the charge path. | |
867578cb | 1953 | */ |
17c56de6 | 1954 | if (READ_ONCE(memcg->oom_kill_disable)) { |
becdf89d SB |
1955 | if (current->in_user_fault) { |
1956 | css_get(&memcg->css); | |
1957 | current->memcg_in_oom = memcg; | |
1958 | current->memcg_oom_gfp_mask = mask; | |
1959 | current->memcg_oom_order = order; | |
1960 | } | |
1961 | return false; | |
29ef680a MH |
1962 | } |
1963 | ||
7056d3a3 MH |
1964 | mem_cgroup_mark_under_oom(memcg); |
1965 | ||
1966 | locked = mem_cgroup_oom_trylock(memcg); | |
1967 | ||
1968 | if (locked) | |
1969 | mem_cgroup_oom_notify(memcg); | |
1970 | ||
1971 | mem_cgroup_unmark_under_oom(memcg); | |
becdf89d | 1972 | ret = mem_cgroup_out_of_memory(memcg, mask, order); |
7056d3a3 MH |
1973 | |
1974 | if (locked) | |
1975 | mem_cgroup_oom_unlock(memcg); | |
29ef680a | 1976 | |
7056d3a3 | 1977 | return ret; |
3812c8c8 JW |
1978 | } |
1979 | ||
1980 | /** | |
1981 | * mem_cgroup_oom_synchronize - complete memcg OOM handling | |
49426420 | 1982 | * @handle: actually kill/wait or just clean up the OOM state |
3812c8c8 | 1983 | * |
49426420 JW |
1984 | * This has to be called at the end of a page fault if the memcg OOM |
1985 | * handler was enabled. | |
3812c8c8 | 1986 | * |
49426420 | 1987 | * Memcg supports userspace OOM handling where failed allocations must |
3812c8c8 JW |
1988 | * sleep on a waitqueue until the userspace task resolves the |
1989 | * situation. Sleeping directly in the charge context with all kinds | |
1990 | * of locks held is not a good idea, instead we remember an OOM state | |
1991 | * in the task and mem_cgroup_oom_synchronize() has to be called at | |
49426420 | 1992 | * the end of the page fault to complete the OOM handling. |
3812c8c8 JW |
1993 | * |
1994 | * Returns %true if an ongoing memcg OOM situation was detected and | |
49426420 | 1995 | * completed, %false otherwise. |
3812c8c8 | 1996 | */ |
49426420 | 1997 | bool mem_cgroup_oom_synchronize(bool handle) |
3812c8c8 | 1998 | { |
626ebc41 | 1999 | struct mem_cgroup *memcg = current->memcg_in_oom; |
3812c8c8 | 2000 | struct oom_wait_info owait; |
49426420 | 2001 | bool locked; |
3812c8c8 JW |
2002 | |
2003 | /* OOM is global, do not handle */ | |
3812c8c8 | 2004 | if (!memcg) |
49426420 | 2005 | return false; |
3812c8c8 | 2006 | |
7c5f64f8 | 2007 | if (!handle) |
49426420 | 2008 | goto cleanup; |
3812c8c8 JW |
2009 | |
2010 | owait.memcg = memcg; | |
2011 | owait.wait.flags = 0; | |
2012 | owait.wait.func = memcg_oom_wake_function; | |
2013 | owait.wait.private = current; | |
2055da97 | 2014 | INIT_LIST_HEAD(&owait.wait.entry); |
867578cb | 2015 | |
3812c8c8 | 2016 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
49426420 JW |
2017 | mem_cgroup_mark_under_oom(memcg); |
2018 | ||
2019 | locked = mem_cgroup_oom_trylock(memcg); | |
2020 | ||
2021 | if (locked) | |
2022 | mem_cgroup_oom_notify(memcg); | |
2023 | ||
857f2139 HX |
2024 | schedule(); |
2025 | mem_cgroup_unmark_under_oom(memcg); | |
2026 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
49426420 | 2027 | |
18b1d18b | 2028 | if (locked) |
fb2a6fc5 | 2029 | mem_cgroup_oom_unlock(memcg); |
49426420 | 2030 | cleanup: |
626ebc41 | 2031 | current->memcg_in_oom = NULL; |
3812c8c8 | 2032 | css_put(&memcg->css); |
867578cb | 2033 | return true; |
0b7f569e KH |
2034 | } |
2035 | ||
3d8b38eb RG |
2036 | /** |
2037 | * mem_cgroup_get_oom_group - get a memory cgroup to clean up after OOM | |
2038 | * @victim: task to be killed by the OOM killer | |
2039 | * @oom_domain: memcg in case of memcg OOM, NULL in case of system-wide OOM | |
2040 | * | |
2041 | * Returns a pointer to a memory cgroup, which has to be cleaned up | |
2042 | * by killing all belonging OOM-killable tasks. | |
2043 | * | |
2044 | * Caller has to call mem_cgroup_put() on the returned non-NULL memcg. | |
2045 | */ | |
2046 | struct mem_cgroup *mem_cgroup_get_oom_group(struct task_struct *victim, | |
2047 | struct mem_cgroup *oom_domain) | |
2048 | { | |
2049 | struct mem_cgroup *oom_group = NULL; | |
2050 | struct mem_cgroup *memcg; | |
2051 | ||
2052 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
2053 | return NULL; | |
2054 | ||
2055 | if (!oom_domain) | |
2056 | oom_domain = root_mem_cgroup; | |
2057 | ||
2058 | rcu_read_lock(); | |
2059 | ||
2060 | memcg = mem_cgroup_from_task(victim); | |
7848ed62 | 2061 | if (mem_cgroup_is_root(memcg)) |
3d8b38eb RG |
2062 | goto out; |
2063 | ||
48fe267c RG |
2064 | /* |
2065 | * If the victim task has been asynchronously moved to a different | |
2066 | * memory cgroup, we might end up killing tasks outside oom_domain. | |
2067 | * In this case it's better to ignore memory.group.oom. | |
2068 | */ | |
2069 | if (unlikely(!mem_cgroup_is_descendant(memcg, oom_domain))) | |
2070 | goto out; | |
2071 | ||
3d8b38eb RG |
2072 | /* |
2073 | * Traverse the memory cgroup hierarchy from the victim task's | |
2074 | * cgroup up to the OOMing cgroup (or root) to find the | |
2075 | * highest-level memory cgroup with oom.group set. | |
2076 | */ | |
2077 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
eaf7b66b | 2078 | if (READ_ONCE(memcg->oom_group)) |
3d8b38eb RG |
2079 | oom_group = memcg; |
2080 | ||
2081 | if (memcg == oom_domain) | |
2082 | break; | |
2083 | } | |
2084 | ||
2085 | if (oom_group) | |
2086 | css_get(&oom_group->css); | |
2087 | out: | |
2088 | rcu_read_unlock(); | |
2089 | ||
2090 | return oom_group; | |
2091 | } | |
2092 | ||
2093 | void mem_cgroup_print_oom_group(struct mem_cgroup *memcg) | |
2094 | { | |
2095 | pr_info("Tasks in "); | |
2096 | pr_cont_cgroup_path(memcg->css.cgroup); | |
2097 | pr_cont(" are going to be killed due to memory.oom.group set\n"); | |
2098 | } | |
2099 | ||
d7365e78 | 2100 | /** |
f70ad448 MWO |
2101 | * folio_memcg_lock - Bind a folio to its memcg. |
2102 | * @folio: The folio. | |
32047e2a | 2103 | * |
f70ad448 | 2104 | * This function prevents unlocked LRU folios from being moved to |
739f79fc JW |
2105 | * another cgroup. |
2106 | * | |
f70ad448 MWO |
2107 | * It ensures lifetime of the bound memcg. The caller is responsible |
2108 | * for the lifetime of the folio. | |
d69b042f | 2109 | */ |
f70ad448 | 2110 | void folio_memcg_lock(struct folio *folio) |
89c06bd5 KH |
2111 | { |
2112 | struct mem_cgroup *memcg; | |
6de22619 | 2113 | unsigned long flags; |
89c06bd5 | 2114 | |
6de22619 JW |
2115 | /* |
2116 | * The RCU lock is held throughout the transaction. The fast | |
2117 | * path can get away without acquiring the memcg->move_lock | |
2118 | * because page moving starts with an RCU grace period. | |
739f79fc | 2119 | */ |
d7365e78 JW |
2120 | rcu_read_lock(); |
2121 | ||
2122 | if (mem_cgroup_disabled()) | |
1c824a68 | 2123 | return; |
89c06bd5 | 2124 | again: |
f70ad448 | 2125 | memcg = folio_memcg(folio); |
29833315 | 2126 | if (unlikely(!memcg)) |
1c824a68 | 2127 | return; |
d7365e78 | 2128 | |
20ad50d6 AS |
2129 | #ifdef CONFIG_PROVE_LOCKING |
2130 | local_irq_save(flags); | |
2131 | might_lock(&memcg->move_lock); | |
2132 | local_irq_restore(flags); | |
2133 | #endif | |
2134 | ||
bdcbb659 | 2135 | if (atomic_read(&memcg->moving_account) <= 0) |
1c824a68 | 2136 | return; |
89c06bd5 | 2137 | |
6de22619 | 2138 | spin_lock_irqsave(&memcg->move_lock, flags); |
f70ad448 | 2139 | if (memcg != folio_memcg(folio)) { |
6de22619 | 2140 | spin_unlock_irqrestore(&memcg->move_lock, flags); |
89c06bd5 KH |
2141 | goto again; |
2142 | } | |
6de22619 JW |
2143 | |
2144 | /* | |
1c824a68 JW |
2145 | * When charge migration first begins, we can have multiple |
2146 | * critical sections holding the fast-path RCU lock and one | |
2147 | * holding the slowpath move_lock. Track the task who has the | |
6c77b607 | 2148 | * move_lock for folio_memcg_unlock(). |
6de22619 JW |
2149 | */ |
2150 | memcg->move_lock_task = current; | |
2151 | memcg->move_lock_flags = flags; | |
89c06bd5 | 2152 | } |
f70ad448 | 2153 | |
f70ad448 | 2154 | static void __folio_memcg_unlock(struct mem_cgroup *memcg) |
89c06bd5 | 2155 | { |
6de22619 JW |
2156 | if (memcg && memcg->move_lock_task == current) { |
2157 | unsigned long flags = memcg->move_lock_flags; | |
2158 | ||
2159 | memcg->move_lock_task = NULL; | |
2160 | memcg->move_lock_flags = 0; | |
2161 | ||
2162 | spin_unlock_irqrestore(&memcg->move_lock, flags); | |
2163 | } | |
89c06bd5 | 2164 | |
d7365e78 | 2165 | rcu_read_unlock(); |
89c06bd5 | 2166 | } |
739f79fc JW |
2167 | |
2168 | /** | |
f70ad448 MWO |
2169 | * folio_memcg_unlock - Release the binding between a folio and its memcg. |
2170 | * @folio: The folio. | |
2171 | * | |
2172 | * This releases the binding created by folio_memcg_lock(). This does | |
2173 | * not change the accounting of this folio to its memcg, but it does | |
2174 | * permit others to change it. | |
739f79fc | 2175 | */ |
f70ad448 | 2176 | void folio_memcg_unlock(struct folio *folio) |
739f79fc | 2177 | { |
f70ad448 MWO |
2178 | __folio_memcg_unlock(folio_memcg(folio)); |
2179 | } | |
9da7b521 | 2180 | |
fead2b86 | 2181 | struct memcg_stock_pcp { |
56751146 | 2182 | local_lock_t stock_lock; |
fead2b86 MH |
2183 | struct mem_cgroup *cached; /* this never be root cgroup */ |
2184 | unsigned int nr_pages; | |
2185 | ||
bf4f0599 RG |
2186 | #ifdef CONFIG_MEMCG_KMEM |
2187 | struct obj_cgroup *cached_objcg; | |
68ac5b3c | 2188 | struct pglist_data *cached_pgdat; |
bf4f0599 | 2189 | unsigned int nr_bytes; |
68ac5b3c WL |
2190 | int nr_slab_reclaimable_b; |
2191 | int nr_slab_unreclaimable_b; | |
bf4f0599 RG |
2192 | #endif |
2193 | ||
cdec2e42 | 2194 | struct work_struct work; |
26fe6168 | 2195 | unsigned long flags; |
a0db00fc | 2196 | #define FLUSHING_CACHED_CHARGE 0 |
cdec2e42 | 2197 | }; |
56751146 SAS |
2198 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock) = { |
2199 | .stock_lock = INIT_LOCAL_LOCK(stock_lock), | |
2200 | }; | |
9f50fad6 | 2201 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 | 2202 | |
bf4f0599 | 2203 | #ifdef CONFIG_MEMCG_KMEM |
56751146 | 2204 | static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock); |
bf4f0599 RG |
2205 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, |
2206 | struct mem_cgroup *root_memcg); | |
a8c49af3 | 2207 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages); |
bf4f0599 RG |
2208 | |
2209 | #else | |
56751146 | 2210 | static inline struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) |
bf4f0599 | 2211 | { |
56751146 | 2212 | return NULL; |
bf4f0599 RG |
2213 | } |
2214 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, | |
2215 | struct mem_cgroup *root_memcg) | |
2216 | { | |
2217 | return false; | |
2218 | } | |
a8c49af3 YA |
2219 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) |
2220 | { | |
2221 | } | |
bf4f0599 RG |
2222 | #endif |
2223 | ||
a0956d54 SS |
2224 | /** |
2225 | * consume_stock: Try to consume stocked charge on this cpu. | |
2226 | * @memcg: memcg to consume from. | |
2227 | * @nr_pages: how many pages to charge. | |
2228 | * | |
2229 | * The charges will only happen if @memcg matches the current cpu's memcg | |
2230 | * stock, and at least @nr_pages are available in that stock. Failure to | |
2231 | * service an allocation will refill the stock. | |
2232 | * | |
2233 | * returns true if successful, false otherwise. | |
cdec2e42 | 2234 | */ |
a0956d54 | 2235 | static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
2236 | { |
2237 | struct memcg_stock_pcp *stock; | |
db2ba40c | 2238 | unsigned long flags; |
3e32cb2e | 2239 | bool ret = false; |
cdec2e42 | 2240 | |
a983b5eb | 2241 | if (nr_pages > MEMCG_CHARGE_BATCH) |
3e32cb2e | 2242 | return ret; |
a0956d54 | 2243 | |
56751146 | 2244 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
db2ba40c JW |
2245 | |
2246 | stock = this_cpu_ptr(&memcg_stock); | |
f785a8f2 | 2247 | if (memcg == READ_ONCE(stock->cached) && stock->nr_pages >= nr_pages) { |
a0956d54 | 2248 | stock->nr_pages -= nr_pages; |
3e32cb2e JW |
2249 | ret = true; |
2250 | } | |
db2ba40c | 2251 | |
56751146 | 2252 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
db2ba40c | 2253 | |
cdec2e42 KH |
2254 | return ret; |
2255 | } | |
2256 | ||
2257 | /* | |
3e32cb2e | 2258 | * Returns stocks cached in percpu and reset cached information. |
cdec2e42 KH |
2259 | */ |
2260 | static void drain_stock(struct memcg_stock_pcp *stock) | |
2261 | { | |
f785a8f2 | 2262 | struct mem_cgroup *old = READ_ONCE(stock->cached); |
cdec2e42 | 2263 | |
1a3e1f40 JW |
2264 | if (!old) |
2265 | return; | |
2266 | ||
11c9ea4e | 2267 | if (stock->nr_pages) { |
3e32cb2e | 2268 | page_counter_uncharge(&old->memory, stock->nr_pages); |
7941d214 | 2269 | if (do_memsw_account()) |
3e32cb2e | 2270 | page_counter_uncharge(&old->memsw, stock->nr_pages); |
11c9ea4e | 2271 | stock->nr_pages = 0; |
cdec2e42 | 2272 | } |
1a3e1f40 JW |
2273 | |
2274 | css_put(&old->css); | |
f785a8f2 | 2275 | WRITE_ONCE(stock->cached, NULL); |
cdec2e42 KH |
2276 | } |
2277 | ||
cdec2e42 KH |
2278 | static void drain_local_stock(struct work_struct *dummy) |
2279 | { | |
db2ba40c | 2280 | struct memcg_stock_pcp *stock; |
56751146 | 2281 | struct obj_cgroup *old = NULL; |
db2ba40c JW |
2282 | unsigned long flags; |
2283 | ||
72f0184c | 2284 | /* |
5c49cf9a MH |
2285 | * The only protection from cpu hotplug (memcg_hotplug_cpu_dead) vs. |
2286 | * drain_stock races is that we always operate on local CPU stock | |
2287 | * here with IRQ disabled | |
72f0184c | 2288 | */ |
56751146 | 2289 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
db2ba40c JW |
2290 | |
2291 | stock = this_cpu_ptr(&memcg_stock); | |
56751146 | 2292 | old = drain_obj_stock(stock); |
cdec2e42 | 2293 | drain_stock(stock); |
26fe6168 | 2294 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
db2ba40c | 2295 | |
56751146 SAS |
2296 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
2297 | if (old) | |
2298 | obj_cgroup_put(old); | |
cdec2e42 KH |
2299 | } |
2300 | ||
2301 | /* | |
3e32cb2e | 2302 | * Cache charges(val) to local per_cpu area. |
320cc51d | 2303 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 2304 | */ |
af9a3b69 | 2305 | static void __refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 | 2306 | { |
db2ba40c | 2307 | struct memcg_stock_pcp *stock; |
cdec2e42 | 2308 | |
db2ba40c | 2309 | stock = this_cpu_ptr(&memcg_stock); |
f785a8f2 | 2310 | if (READ_ONCE(stock->cached) != memcg) { /* reset if necessary */ |
cdec2e42 | 2311 | drain_stock(stock); |
1a3e1f40 | 2312 | css_get(&memcg->css); |
f785a8f2 | 2313 | WRITE_ONCE(stock->cached, memcg); |
cdec2e42 | 2314 | } |
11c9ea4e | 2315 | stock->nr_pages += nr_pages; |
db2ba40c | 2316 | |
a983b5eb | 2317 | if (stock->nr_pages > MEMCG_CHARGE_BATCH) |
475d0487 | 2318 | drain_stock(stock); |
af9a3b69 JW |
2319 | } |
2320 | ||
2321 | static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) | |
2322 | { | |
2323 | unsigned long flags; | |
475d0487 | 2324 | |
56751146 | 2325 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
af9a3b69 | 2326 | __refill_stock(memcg, nr_pages); |
56751146 | 2327 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
cdec2e42 KH |
2328 | } |
2329 | ||
2330 | /* | |
c0ff4b85 | 2331 | * Drains all per-CPU charge caches for given root_memcg resp. subtree |
6d3d6aa2 | 2332 | * of the hierarchy under it. |
cdec2e42 | 2333 | */ |
6d3d6aa2 | 2334 | static void drain_all_stock(struct mem_cgroup *root_memcg) |
cdec2e42 | 2335 | { |
26fe6168 | 2336 | int cpu, curcpu; |
d38144b7 | 2337 | |
6d3d6aa2 JW |
2338 | /* If someone's already draining, avoid adding running more workers. */ |
2339 | if (!mutex_trylock(&percpu_charge_mutex)) | |
2340 | return; | |
72f0184c MH |
2341 | /* |
2342 | * Notify other cpus that system-wide "drain" is running | |
2343 | * We do not care about races with the cpu hotplug because cpu down | |
2344 | * as well as workers from this path always operate on the local | |
2345 | * per-cpu data. CPU up doesn't touch memcg_stock at all. | |
2346 | */ | |
0790ed62 SAS |
2347 | migrate_disable(); |
2348 | curcpu = smp_processor_id(); | |
cdec2e42 KH |
2349 | for_each_online_cpu(cpu) { |
2350 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
c0ff4b85 | 2351 | struct mem_cgroup *memcg; |
e1a366be | 2352 | bool flush = false; |
26fe6168 | 2353 | |
e1a366be | 2354 | rcu_read_lock(); |
f785a8f2 | 2355 | memcg = READ_ONCE(stock->cached); |
e1a366be RG |
2356 | if (memcg && stock->nr_pages && |
2357 | mem_cgroup_is_descendant(memcg, root_memcg)) | |
2358 | flush = true; | |
27fb0956 | 2359 | else if (obj_stock_flush_required(stock, root_memcg)) |
bf4f0599 | 2360 | flush = true; |
e1a366be RG |
2361 | rcu_read_unlock(); |
2362 | ||
2363 | if (flush && | |
2364 | !test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { | |
d1a05b69 MH |
2365 | if (cpu == curcpu) |
2366 | drain_local_stock(&stock->work); | |
6a792697 | 2367 | else if (!cpu_is_isolated(cpu)) |
d1a05b69 MH |
2368 | schedule_work_on(cpu, &stock->work); |
2369 | } | |
cdec2e42 | 2370 | } |
0790ed62 | 2371 | migrate_enable(); |
9f50fad6 | 2372 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2373 | } |
2374 | ||
2cd21c89 JW |
2375 | static int memcg_hotplug_cpu_dead(unsigned int cpu) |
2376 | { | |
2377 | struct memcg_stock_pcp *stock; | |
a3d4c05a | 2378 | |
2cd21c89 JW |
2379 | stock = &per_cpu(memcg_stock, cpu); |
2380 | drain_stock(stock); | |
a3d4c05a | 2381 | |
308167fc | 2382 | return 0; |
cdec2e42 KH |
2383 | } |
2384 | ||
b3ff9291 CD |
2385 | static unsigned long reclaim_high(struct mem_cgroup *memcg, |
2386 | unsigned int nr_pages, | |
2387 | gfp_t gfp_mask) | |
f7e1cb6e | 2388 | { |
b3ff9291 CD |
2389 | unsigned long nr_reclaimed = 0; |
2390 | ||
f7e1cb6e | 2391 | do { |
e22c6ed9 JW |
2392 | unsigned long pflags; |
2393 | ||
d1663a90 JK |
2394 | if (page_counter_read(&memcg->memory) <= |
2395 | READ_ONCE(memcg->memory.high)) | |
f7e1cb6e | 2396 | continue; |
e22c6ed9 | 2397 | |
e27be240 | 2398 | memcg_memory_event(memcg, MEMCG_HIGH); |
e22c6ed9 JW |
2399 | |
2400 | psi_memstall_enter(&pflags); | |
b3ff9291 | 2401 | nr_reclaimed += try_to_free_mem_cgroup_pages(memcg, nr_pages, |
73b73bac | 2402 | gfp_mask, |
55ab834a | 2403 | MEMCG_RECLAIM_MAY_SWAP); |
e22c6ed9 | 2404 | psi_memstall_leave(&pflags); |
4bf17307 CD |
2405 | } while ((memcg = parent_mem_cgroup(memcg)) && |
2406 | !mem_cgroup_is_root(memcg)); | |
b3ff9291 CD |
2407 | |
2408 | return nr_reclaimed; | |
f7e1cb6e JW |
2409 | } |
2410 | ||
2411 | static void high_work_func(struct work_struct *work) | |
2412 | { | |
2413 | struct mem_cgroup *memcg; | |
2414 | ||
2415 | memcg = container_of(work, struct mem_cgroup, high_work); | |
a983b5eb | 2416 | reclaim_high(memcg, MEMCG_CHARGE_BATCH, GFP_KERNEL); |
f7e1cb6e JW |
2417 | } |
2418 | ||
0e4b01df CD |
2419 | /* |
2420 | * Clamp the maximum sleep time per allocation batch to 2 seconds. This is | |
2421 | * enough to still cause a significant slowdown in most cases, while still | |
2422 | * allowing diagnostics and tracing to proceed without becoming stuck. | |
2423 | */ | |
2424 | #define MEMCG_MAX_HIGH_DELAY_JIFFIES (2UL*HZ) | |
2425 | ||
2426 | /* | |
2427 | * When calculating the delay, we use these either side of the exponentiation to | |
2428 | * maintain precision and scale to a reasonable number of jiffies (see the table | |
2429 | * below. | |
2430 | * | |
2431 | * - MEMCG_DELAY_PRECISION_SHIFT: Extra precision bits while translating the | |
2432 | * overage ratio to a delay. | |
ac5ddd0f | 2433 | * - MEMCG_DELAY_SCALING_SHIFT: The number of bits to scale down the |
0e4b01df CD |
2434 | * proposed penalty in order to reduce to a reasonable number of jiffies, and |
2435 | * to produce a reasonable delay curve. | |
2436 | * | |
2437 | * MEMCG_DELAY_SCALING_SHIFT just happens to be a number that produces a | |
2438 | * reasonable delay curve compared to precision-adjusted overage, not | |
2439 | * penalising heavily at first, but still making sure that growth beyond the | |
2440 | * limit penalises misbehaviour cgroups by slowing them down exponentially. For | |
2441 | * example, with a high of 100 megabytes: | |
2442 | * | |
2443 | * +-------+------------------------+ | |
2444 | * | usage | time to allocate in ms | | |
2445 | * +-------+------------------------+ | |
2446 | * | 100M | 0 | | |
2447 | * | 101M | 6 | | |
2448 | * | 102M | 25 | | |
2449 | * | 103M | 57 | | |
2450 | * | 104M | 102 | | |
2451 | * | 105M | 159 | | |
2452 | * | 106M | 230 | | |
2453 | * | 107M | 313 | | |
2454 | * | 108M | 409 | | |
2455 | * | 109M | 518 | | |
2456 | * | 110M | 639 | | |
2457 | * | 111M | 774 | | |
2458 | * | 112M | 921 | | |
2459 | * | 113M | 1081 | | |
2460 | * | 114M | 1254 | | |
2461 | * | 115M | 1439 | | |
2462 | * | 116M | 1638 | | |
2463 | * | 117M | 1849 | | |
2464 | * | 118M | 2000 | | |
2465 | * | 119M | 2000 | | |
2466 | * | 120M | 2000 | | |
2467 | * +-------+------------------------+ | |
2468 | */ | |
2469 | #define MEMCG_DELAY_PRECISION_SHIFT 20 | |
2470 | #define MEMCG_DELAY_SCALING_SHIFT 14 | |
2471 | ||
8a5dbc65 | 2472 | static u64 calculate_overage(unsigned long usage, unsigned long high) |
b23afb93 | 2473 | { |
8a5dbc65 | 2474 | u64 overage; |
b23afb93 | 2475 | |
8a5dbc65 JK |
2476 | if (usage <= high) |
2477 | return 0; | |
e26733e0 | 2478 | |
8a5dbc65 JK |
2479 | /* |
2480 | * Prevent division by 0 in overage calculation by acting as if | |
2481 | * it was a threshold of 1 page | |
2482 | */ | |
2483 | high = max(high, 1UL); | |
9b8b1754 | 2484 | |
8a5dbc65 JK |
2485 | overage = usage - high; |
2486 | overage <<= MEMCG_DELAY_PRECISION_SHIFT; | |
2487 | return div64_u64(overage, high); | |
2488 | } | |
e26733e0 | 2489 | |
8a5dbc65 JK |
2490 | static u64 mem_find_max_overage(struct mem_cgroup *memcg) |
2491 | { | |
2492 | u64 overage, max_overage = 0; | |
e26733e0 | 2493 | |
8a5dbc65 JK |
2494 | do { |
2495 | overage = calculate_overage(page_counter_read(&memcg->memory), | |
d1663a90 | 2496 | READ_ONCE(memcg->memory.high)); |
8a5dbc65 | 2497 | max_overage = max(overage, max_overage); |
e26733e0 CD |
2498 | } while ((memcg = parent_mem_cgroup(memcg)) && |
2499 | !mem_cgroup_is_root(memcg)); | |
2500 | ||
8a5dbc65 JK |
2501 | return max_overage; |
2502 | } | |
2503 | ||
4b82ab4f JK |
2504 | static u64 swap_find_max_overage(struct mem_cgroup *memcg) |
2505 | { | |
2506 | u64 overage, max_overage = 0; | |
2507 | ||
2508 | do { | |
2509 | overage = calculate_overage(page_counter_read(&memcg->swap), | |
2510 | READ_ONCE(memcg->swap.high)); | |
2511 | if (overage) | |
2512 | memcg_memory_event(memcg, MEMCG_SWAP_HIGH); | |
2513 | max_overage = max(overage, max_overage); | |
2514 | } while ((memcg = parent_mem_cgroup(memcg)) && | |
2515 | !mem_cgroup_is_root(memcg)); | |
2516 | ||
2517 | return max_overage; | |
2518 | } | |
2519 | ||
8a5dbc65 JK |
2520 | /* |
2521 | * Get the number of jiffies that we should penalise a mischievous cgroup which | |
2522 | * is exceeding its memory.high by checking both it and its ancestors. | |
2523 | */ | |
2524 | static unsigned long calculate_high_delay(struct mem_cgroup *memcg, | |
2525 | unsigned int nr_pages, | |
2526 | u64 max_overage) | |
2527 | { | |
2528 | unsigned long penalty_jiffies; | |
2529 | ||
e26733e0 CD |
2530 | if (!max_overage) |
2531 | return 0; | |
0e4b01df CD |
2532 | |
2533 | /* | |
0e4b01df CD |
2534 | * We use overage compared to memory.high to calculate the number of |
2535 | * jiffies to sleep (penalty_jiffies). Ideally this value should be | |
2536 | * fairly lenient on small overages, and increasingly harsh when the | |
2537 | * memcg in question makes it clear that it has no intention of stopping | |
2538 | * its crazy behaviour, so we exponentially increase the delay based on | |
2539 | * overage amount. | |
2540 | */ | |
e26733e0 CD |
2541 | penalty_jiffies = max_overage * max_overage * HZ; |
2542 | penalty_jiffies >>= MEMCG_DELAY_PRECISION_SHIFT; | |
2543 | penalty_jiffies >>= MEMCG_DELAY_SCALING_SHIFT; | |
0e4b01df CD |
2544 | |
2545 | /* | |
2546 | * Factor in the task's own contribution to the overage, such that four | |
2547 | * N-sized allocations are throttled approximately the same as one | |
2548 | * 4N-sized allocation. | |
2549 | * | |
2550 | * MEMCG_CHARGE_BATCH pages is nominal, so work out how much smaller or | |
2551 | * larger the current charge patch is than that. | |
2552 | */ | |
ff144e69 | 2553 | return penalty_jiffies * nr_pages / MEMCG_CHARGE_BATCH; |
e26733e0 CD |
2554 | } |
2555 | ||
2556 | /* | |
2557 | * Scheduled by try_charge() to be executed from the userland return path | |
2558 | * and reclaims memory over the high limit. | |
2559 | */ | |
9ea9cb00 | 2560 | void mem_cgroup_handle_over_high(gfp_t gfp_mask) |
e26733e0 CD |
2561 | { |
2562 | unsigned long penalty_jiffies; | |
2563 | unsigned long pflags; | |
b3ff9291 | 2564 | unsigned long nr_reclaimed; |
e26733e0 | 2565 | unsigned int nr_pages = current->memcg_nr_pages_over_high; |
d977aa93 | 2566 | int nr_retries = MAX_RECLAIM_RETRIES; |
e26733e0 | 2567 | struct mem_cgroup *memcg; |
b3ff9291 | 2568 | bool in_retry = false; |
e26733e0 CD |
2569 | |
2570 | if (likely(!nr_pages)) | |
2571 | return; | |
2572 | ||
2573 | memcg = get_mem_cgroup_from_mm(current->mm); | |
e26733e0 CD |
2574 | current->memcg_nr_pages_over_high = 0; |
2575 | ||
b3ff9291 CD |
2576 | retry_reclaim: |
2577 | /* | |
2578 | * The allocating task should reclaim at least the batch size, but for | |
2579 | * subsequent retries we only want to do what's necessary to prevent oom | |
2580 | * or breaching resource isolation. | |
2581 | * | |
2582 | * This is distinct from memory.max or page allocator behaviour because | |
2583 | * memory.high is currently batched, whereas memory.max and the page | |
2584 | * allocator run every time an allocation is made. | |
2585 | */ | |
2586 | nr_reclaimed = reclaim_high(memcg, | |
2587 | in_retry ? SWAP_CLUSTER_MAX : nr_pages, | |
9ea9cb00 | 2588 | gfp_mask); |
b3ff9291 | 2589 | |
e26733e0 CD |
2590 | /* |
2591 | * memory.high is breached and reclaim is unable to keep up. Throttle | |
2592 | * allocators proactively to slow down excessive growth. | |
2593 | */ | |
8a5dbc65 JK |
2594 | penalty_jiffies = calculate_high_delay(memcg, nr_pages, |
2595 | mem_find_max_overage(memcg)); | |
0e4b01df | 2596 | |
4b82ab4f JK |
2597 | penalty_jiffies += calculate_high_delay(memcg, nr_pages, |
2598 | swap_find_max_overage(memcg)); | |
2599 | ||
ff144e69 JK |
2600 | /* |
2601 | * Clamp the max delay per usermode return so as to still keep the | |
2602 | * application moving forwards and also permit diagnostics, albeit | |
2603 | * extremely slowly. | |
2604 | */ | |
2605 | penalty_jiffies = min(penalty_jiffies, MEMCG_MAX_HIGH_DELAY_JIFFIES); | |
2606 | ||
0e4b01df CD |
2607 | /* |
2608 | * Don't sleep if the amount of jiffies this memcg owes us is so low | |
2609 | * that it's not even worth doing, in an attempt to be nice to those who | |
2610 | * go only a small amount over their memory.high value and maybe haven't | |
2611 | * been aggressively reclaimed enough yet. | |
2612 | */ | |
2613 | if (penalty_jiffies <= HZ / 100) | |
2614 | goto out; | |
2615 | ||
b3ff9291 CD |
2616 | /* |
2617 | * If reclaim is making forward progress but we're still over | |
2618 | * memory.high, we want to encourage that rather than doing allocator | |
2619 | * throttling. | |
2620 | */ | |
2621 | if (nr_reclaimed || nr_retries--) { | |
2622 | in_retry = true; | |
2623 | goto retry_reclaim; | |
2624 | } | |
2625 | ||
0e4b01df CD |
2626 | /* |
2627 | * If we exit early, we're guaranteed to die (since | |
2628 | * schedule_timeout_killable sets TASK_KILLABLE). This means we don't | |
2629 | * need to account for any ill-begotten jiffies to pay them off later. | |
2630 | */ | |
2631 | psi_memstall_enter(&pflags); | |
2632 | schedule_timeout_killable(penalty_jiffies); | |
2633 | psi_memstall_leave(&pflags); | |
2634 | ||
2635 | out: | |
2636 | css_put(&memcg->css); | |
b23afb93 TH |
2637 | } |
2638 | ||
c5c8b16b MS |
2639 | static int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask, |
2640 | unsigned int nr_pages) | |
8a9f3ccd | 2641 | { |
a983b5eb | 2642 | unsigned int batch = max(MEMCG_CHARGE_BATCH, nr_pages); |
d977aa93 | 2643 | int nr_retries = MAX_RECLAIM_RETRIES; |
6539cc05 | 2644 | struct mem_cgroup *mem_over_limit; |
3e32cb2e | 2645 | struct page_counter *counter; |
6539cc05 | 2646 | unsigned long nr_reclaimed; |
a4ebf1b6 | 2647 | bool passed_oom = false; |
73b73bac | 2648 | unsigned int reclaim_options = MEMCG_RECLAIM_MAY_SWAP; |
b70a2a21 | 2649 | bool drained = false; |
d6e103a7 | 2650 | bool raised_max_event = false; |
e22c6ed9 | 2651 | unsigned long pflags; |
a636b327 | 2652 | |
6539cc05 | 2653 | retry: |
b6b6cc72 | 2654 | if (consume_stock(memcg, nr_pages)) |
10d53c74 | 2655 | return 0; |
8a9f3ccd | 2656 | |
7941d214 | 2657 | if (!do_memsw_account() || |
6071ca52 JW |
2658 | page_counter_try_charge(&memcg->memsw, batch, &counter)) { |
2659 | if (page_counter_try_charge(&memcg->memory, batch, &counter)) | |
6539cc05 | 2660 | goto done_restock; |
7941d214 | 2661 | if (do_memsw_account()) |
3e32cb2e JW |
2662 | page_counter_uncharge(&memcg->memsw, batch); |
2663 | mem_over_limit = mem_cgroup_from_counter(counter, memory); | |
3fbe7244 | 2664 | } else { |
3e32cb2e | 2665 | mem_over_limit = mem_cgroup_from_counter(counter, memsw); |
73b73bac | 2666 | reclaim_options &= ~MEMCG_RECLAIM_MAY_SWAP; |
3fbe7244 | 2667 | } |
7a81b88c | 2668 | |
6539cc05 JW |
2669 | if (batch > nr_pages) { |
2670 | batch = nr_pages; | |
2671 | goto retry; | |
2672 | } | |
6d61ef40 | 2673 | |
89a28483 JW |
2674 | /* |
2675 | * Prevent unbounded recursion when reclaim operations need to | |
2676 | * allocate memory. This might exceed the limits temporarily, | |
2677 | * but we prefer facilitating memory reclaim and getting back | |
2678 | * under the limit over triggering OOM kills in these cases. | |
2679 | */ | |
2680 | if (unlikely(current->flags & PF_MEMALLOC)) | |
2681 | goto force; | |
2682 | ||
06b078fc JW |
2683 | if (unlikely(task_in_memcg_oom(current))) |
2684 | goto nomem; | |
2685 | ||
d0164adc | 2686 | if (!gfpflags_allow_blocking(gfp_mask)) |
6539cc05 | 2687 | goto nomem; |
4b534334 | 2688 | |
e27be240 | 2689 | memcg_memory_event(mem_over_limit, MEMCG_MAX); |
d6e103a7 | 2690 | raised_max_event = true; |
241994ed | 2691 | |
e22c6ed9 | 2692 | psi_memstall_enter(&pflags); |
b70a2a21 | 2693 | nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages, |
55ab834a | 2694 | gfp_mask, reclaim_options); |
e22c6ed9 | 2695 | psi_memstall_leave(&pflags); |
6539cc05 | 2696 | |
61e02c74 | 2697 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
6539cc05 | 2698 | goto retry; |
28c34c29 | 2699 | |
b70a2a21 | 2700 | if (!drained) { |
6d3d6aa2 | 2701 | drain_all_stock(mem_over_limit); |
b70a2a21 JW |
2702 | drained = true; |
2703 | goto retry; | |
2704 | } | |
2705 | ||
28c34c29 JW |
2706 | if (gfp_mask & __GFP_NORETRY) |
2707 | goto nomem; | |
6539cc05 JW |
2708 | /* |
2709 | * Even though the limit is exceeded at this point, reclaim | |
2710 | * may have been able to free some pages. Retry the charge | |
2711 | * before killing the task. | |
2712 | * | |
2713 | * Only for regular pages, though: huge pages are rather | |
2714 | * unlikely to succeed so close to the limit, and we fall back | |
2715 | * to regular pages anyway in case of failure. | |
2716 | */ | |
61e02c74 | 2717 | if (nr_reclaimed && nr_pages <= (1 << PAGE_ALLOC_COSTLY_ORDER)) |
6539cc05 JW |
2718 | goto retry; |
2719 | /* | |
2720 | * At task move, charge accounts can be doubly counted. So, it's | |
2721 | * better to wait until the end of task_move if something is going on. | |
2722 | */ | |
2723 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2724 | goto retry; | |
2725 | ||
9b130619 JW |
2726 | if (nr_retries--) |
2727 | goto retry; | |
2728 | ||
38d38493 | 2729 | if (gfp_mask & __GFP_RETRY_MAYFAIL) |
29ef680a MH |
2730 | goto nomem; |
2731 | ||
a4ebf1b6 VA |
2732 | /* Avoid endless loop for tasks bypassed by the oom killer */ |
2733 | if (passed_oom && task_is_dying()) | |
2734 | goto nomem; | |
6539cc05 | 2735 | |
29ef680a MH |
2736 | /* |
2737 | * keep retrying as long as the memcg oom killer is able to make | |
2738 | * a forward progress or bypass the charge if the oom killer | |
2739 | * couldn't make any progress. | |
2740 | */ | |
becdf89d SB |
2741 | if (mem_cgroup_oom(mem_over_limit, gfp_mask, |
2742 | get_order(nr_pages * PAGE_SIZE))) { | |
a4ebf1b6 | 2743 | passed_oom = true; |
d977aa93 | 2744 | nr_retries = MAX_RECLAIM_RETRIES; |
29ef680a | 2745 | goto retry; |
29ef680a | 2746 | } |
7a81b88c | 2747 | nomem: |
1461e8c2 SB |
2748 | /* |
2749 | * Memcg doesn't have a dedicated reserve for atomic | |
2750 | * allocations. But like the global atomic pool, we need to | |
2751 | * put the burden of reclaim on regular allocation requests | |
2752 | * and let these go through as privileged allocations. | |
2753 | */ | |
2754 | if (!(gfp_mask & (__GFP_NOFAIL | __GFP_HIGH))) | |
3168ecbe | 2755 | return -ENOMEM; |
10d53c74 | 2756 | force: |
d6e103a7 RG |
2757 | /* |
2758 | * If the allocation has to be enforced, don't forget to raise | |
2759 | * a MEMCG_MAX event. | |
2760 | */ | |
2761 | if (!raised_max_event) | |
2762 | memcg_memory_event(mem_over_limit, MEMCG_MAX); | |
2763 | ||
10d53c74 TH |
2764 | /* |
2765 | * The allocation either can't fail or will lead to more memory | |
2766 | * being freed very soon. Allow memory usage go over the limit | |
2767 | * temporarily by force charging it. | |
2768 | */ | |
2769 | page_counter_charge(&memcg->memory, nr_pages); | |
7941d214 | 2770 | if (do_memsw_account()) |
10d53c74 | 2771 | page_counter_charge(&memcg->memsw, nr_pages); |
10d53c74 TH |
2772 | |
2773 | return 0; | |
6539cc05 JW |
2774 | |
2775 | done_restock: | |
2776 | if (batch > nr_pages) | |
2777 | refill_stock(memcg, batch - nr_pages); | |
b23afb93 | 2778 | |
241994ed | 2779 | /* |
b23afb93 TH |
2780 | * If the hierarchy is above the normal consumption range, schedule |
2781 | * reclaim on returning to userland. We can perform reclaim here | |
71baba4b | 2782 | * if __GFP_RECLAIM but let's always punt for simplicity and so that |
b23afb93 TH |
2783 | * GFP_KERNEL can consistently be used during reclaim. @memcg is |
2784 | * not recorded as it most likely matches current's and won't | |
2785 | * change in the meantime. As high limit is checked again before | |
2786 | * reclaim, the cost of mismatch is negligible. | |
241994ed JW |
2787 | */ |
2788 | do { | |
4b82ab4f JK |
2789 | bool mem_high, swap_high; |
2790 | ||
2791 | mem_high = page_counter_read(&memcg->memory) > | |
2792 | READ_ONCE(memcg->memory.high); | |
2793 | swap_high = page_counter_read(&memcg->swap) > | |
2794 | READ_ONCE(memcg->swap.high); | |
2795 | ||
2796 | /* Don't bother a random interrupted task */ | |
086f694a | 2797 | if (!in_task()) { |
4b82ab4f | 2798 | if (mem_high) { |
f7e1cb6e JW |
2799 | schedule_work(&memcg->high_work); |
2800 | break; | |
2801 | } | |
4b82ab4f JK |
2802 | continue; |
2803 | } | |
2804 | ||
2805 | if (mem_high || swap_high) { | |
2806 | /* | |
2807 | * The allocating tasks in this cgroup will need to do | |
2808 | * reclaim or be throttled to prevent further growth | |
2809 | * of the memory or swap footprints. | |
2810 | * | |
2811 | * Target some best-effort fairness between the tasks, | |
2812 | * and distribute reclaim work and delay penalties | |
2813 | * based on how much each task is actually allocating. | |
2814 | */ | |
9516a18a | 2815 | current->memcg_nr_pages_over_high += batch; |
b23afb93 TH |
2816 | set_notify_resume(current); |
2817 | break; | |
2818 | } | |
241994ed | 2819 | } while ((memcg = parent_mem_cgroup(memcg))); |
10d53c74 | 2820 | |
c9afe31e SB |
2821 | if (current->memcg_nr_pages_over_high > MEMCG_CHARGE_BATCH && |
2822 | !(current->flags & PF_MEMALLOC) && | |
2823 | gfpflags_allow_blocking(gfp_mask)) { | |
9ea9cb00 | 2824 | mem_cgroup_handle_over_high(gfp_mask); |
c9afe31e | 2825 | } |
10d53c74 | 2826 | return 0; |
7a81b88c | 2827 | } |
8a9f3ccd | 2828 | |
c5c8b16b MS |
2829 | static inline int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, |
2830 | unsigned int nr_pages) | |
2831 | { | |
2832 | if (mem_cgroup_is_root(memcg)) | |
2833 | return 0; | |
2834 | ||
2835 | return try_charge_memcg(memcg, gfp_mask, nr_pages); | |
2836 | } | |
2837 | ||
58056f77 | 2838 | static inline void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) |
a3032a2c | 2839 | { |
ce00a967 JW |
2840 | if (mem_cgroup_is_root(memcg)) |
2841 | return; | |
2842 | ||
3e32cb2e | 2843 | page_counter_uncharge(&memcg->memory, nr_pages); |
7941d214 | 2844 | if (do_memsw_account()) |
3e32cb2e | 2845 | page_counter_uncharge(&memcg->memsw, nr_pages); |
d01dd17f KH |
2846 | } |
2847 | ||
118f2875 | 2848 | static void commit_charge(struct folio *folio, struct mem_cgroup *memcg) |
0a31bc97 | 2849 | { |
118f2875 | 2850 | VM_BUG_ON_FOLIO(folio_memcg(folio), folio); |
0a31bc97 | 2851 | /* |
a5eb011a | 2852 | * Any of the following ensures page's memcg stability: |
0a31bc97 | 2853 | * |
a0b5b414 JW |
2854 | * - the page lock |
2855 | * - LRU isolation | |
6c77b607 | 2856 | * - folio_memcg_lock() |
a0b5b414 | 2857 | * - exclusive reference |
018ee47f | 2858 | * - mem_cgroup_trylock_pages() |
0a31bc97 | 2859 | */ |
118f2875 | 2860 | folio->memcg_data = (unsigned long)memcg; |
7a81b88c | 2861 | } |
66e1707b | 2862 | |
84c07d11 | 2863 | #ifdef CONFIG_MEMCG_KMEM |
41eb5df1 WL |
2864 | /* |
2865 | * The allocated objcg pointers array is not accounted directly. | |
2866 | * Moreover, it should not come from DMA buffer and is not readily | |
2867 | * reclaimable. So those GFP bits should be masked off. | |
2868 | */ | |
2869 | #define OBJCGS_CLEAR_MASK (__GFP_DMA | __GFP_RECLAIMABLE | __GFP_ACCOUNT) | |
2870 | ||
a7ebf564 WL |
2871 | /* |
2872 | * mod_objcg_mlstate() may be called with irq enabled, so | |
2873 | * mod_memcg_lruvec_state() should be used. | |
2874 | */ | |
2875 | static inline void mod_objcg_mlstate(struct obj_cgroup *objcg, | |
2876 | struct pglist_data *pgdat, | |
2877 | enum node_stat_item idx, int nr) | |
2878 | { | |
2879 | struct mem_cgroup *memcg; | |
2880 | struct lruvec *lruvec; | |
2881 | ||
2882 | rcu_read_lock(); | |
2883 | memcg = obj_cgroup_memcg(objcg); | |
2884 | lruvec = mem_cgroup_lruvec(memcg, pgdat); | |
2885 | mod_memcg_lruvec_state(lruvec, idx, nr); | |
2886 | rcu_read_unlock(); | |
2887 | } | |
2888 | ||
4b5f8d9a VB |
2889 | int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, |
2890 | gfp_t gfp, bool new_slab) | |
10befea9 | 2891 | { |
4b5f8d9a | 2892 | unsigned int objects = objs_per_slab(s, slab); |
2e9bd483 | 2893 | unsigned long memcg_data; |
10befea9 RG |
2894 | void *vec; |
2895 | ||
41eb5df1 | 2896 | gfp &= ~OBJCGS_CLEAR_MASK; |
10befea9 | 2897 | vec = kcalloc_node(objects, sizeof(struct obj_cgroup *), gfp, |
4b5f8d9a | 2898 | slab_nid(slab)); |
10befea9 RG |
2899 | if (!vec) |
2900 | return -ENOMEM; | |
2901 | ||
2e9bd483 | 2902 | memcg_data = (unsigned long) vec | MEMCG_DATA_OBJCGS; |
4b5f8d9a | 2903 | if (new_slab) { |
2e9bd483 | 2904 | /* |
4b5f8d9a VB |
2905 | * If the slab is brand new and nobody can yet access its |
2906 | * memcg_data, no synchronization is required and memcg_data can | |
2907 | * be simply assigned. | |
2e9bd483 | 2908 | */ |
4b5f8d9a VB |
2909 | slab->memcg_data = memcg_data; |
2910 | } else if (cmpxchg(&slab->memcg_data, 0, memcg_data)) { | |
2e9bd483 | 2911 | /* |
4b5f8d9a VB |
2912 | * If the slab is already in use, somebody can allocate and |
2913 | * assign obj_cgroups in parallel. In this case the existing | |
2e9bd483 RG |
2914 | * objcg vector should be reused. |
2915 | */ | |
10befea9 | 2916 | kfree(vec); |
2e9bd483 RG |
2917 | return 0; |
2918 | } | |
10befea9 | 2919 | |
2e9bd483 | 2920 | kmemleak_not_leak(vec); |
10befea9 RG |
2921 | return 0; |
2922 | } | |
2923 | ||
fc4db90f RG |
2924 | static __always_inline |
2925 | struct mem_cgroup *mem_cgroup_from_obj_folio(struct folio *folio, void *p) | |
8380ce47 | 2926 | { |
8380ce47 | 2927 | /* |
9855609b RG |
2928 | * Slab objects are accounted individually, not per-page. |
2929 | * Memcg membership data for each individual object is saved in | |
4b5f8d9a | 2930 | * slab->memcg_data. |
8380ce47 | 2931 | */ |
4b5f8d9a VB |
2932 | if (folio_test_slab(folio)) { |
2933 | struct obj_cgroup **objcgs; | |
2934 | struct slab *slab; | |
9855609b RG |
2935 | unsigned int off; |
2936 | ||
4b5f8d9a VB |
2937 | slab = folio_slab(folio); |
2938 | objcgs = slab_objcgs(slab); | |
2939 | if (!objcgs) | |
2940 | return NULL; | |
2941 | ||
2942 | off = obj_to_index(slab->slab_cache, slab, p); | |
2943 | if (objcgs[off]) | |
2944 | return obj_cgroup_memcg(objcgs[off]); | |
10befea9 RG |
2945 | |
2946 | return NULL; | |
9855609b | 2947 | } |
8380ce47 | 2948 | |
bcfe06bf | 2949 | /* |
becacb04 | 2950 | * folio_memcg_check() is used here, because in theory we can encounter |
4b5f8d9a VB |
2951 | * a folio where the slab flag has been cleared already, but |
2952 | * slab->memcg_data has not been freed yet | |
becacb04 | 2953 | * folio_memcg_check() will guarantee that a proper memory |
bcfe06bf RG |
2954 | * cgroup pointer or NULL will be returned. |
2955 | */ | |
becacb04 | 2956 | return folio_memcg_check(folio); |
8380ce47 RG |
2957 | } |
2958 | ||
fc4db90f RG |
2959 | /* |
2960 | * Returns a pointer to the memory cgroup to which the kernel object is charged. | |
2961 | * | |
2962 | * A passed kernel object can be a slab object, vmalloc object or a generic | |
2963 | * kernel page, so different mechanisms for getting the memory cgroup pointer | |
2964 | * should be used. | |
2965 | * | |
2966 | * In certain cases (e.g. kernel stacks or large kmallocs with SLUB) the caller | |
2967 | * can not know for sure how the kernel object is implemented. | |
2968 | * mem_cgroup_from_obj() can be safely used in such cases. | |
2969 | * | |
2970 | * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(), | |
2971 | * cgroup_mutex, etc. | |
2972 | */ | |
2973 | struct mem_cgroup *mem_cgroup_from_obj(void *p) | |
2974 | { | |
2975 | struct folio *folio; | |
2976 | ||
2977 | if (mem_cgroup_disabled()) | |
2978 | return NULL; | |
2979 | ||
2980 | if (unlikely(is_vmalloc_addr(p))) | |
2981 | folio = page_folio(vmalloc_to_page(p)); | |
2982 | else | |
2983 | folio = virt_to_folio(p); | |
2984 | ||
2985 | return mem_cgroup_from_obj_folio(folio, p); | |
2986 | } | |
2987 | ||
2988 | /* | |
2989 | * Returns a pointer to the memory cgroup to which the kernel object is charged. | |
2990 | * Similar to mem_cgroup_from_obj(), but faster and not suitable for objects, | |
2991 | * allocated using vmalloc(). | |
2992 | * | |
2993 | * A passed kernel object must be a slab object or a generic kernel page. | |
2994 | * | |
2995 | * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(), | |
2996 | * cgroup_mutex, etc. | |
2997 | */ | |
2998 | struct mem_cgroup *mem_cgroup_from_slab_obj(void *p) | |
2999 | { | |
3000 | if (mem_cgroup_disabled()) | |
3001 | return NULL; | |
3002 | ||
3003 | return mem_cgroup_from_obj_folio(virt_to_folio(p), p); | |
3004 | } | |
3005 | ||
f4840ccf JW |
3006 | static struct obj_cgroup *__get_obj_cgroup_from_memcg(struct mem_cgroup *memcg) |
3007 | { | |
3008 | struct obj_cgroup *objcg = NULL; | |
3009 | ||
7848ed62 | 3010 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) { |
f4840ccf JW |
3011 | objcg = rcu_dereference(memcg->objcg); |
3012 | if (objcg && obj_cgroup_tryget(objcg)) | |
3013 | break; | |
3014 | objcg = NULL; | |
3015 | } | |
3016 | return objcg; | |
3017 | } | |
3018 | ||
bf4f0599 RG |
3019 | __always_inline struct obj_cgroup *get_obj_cgroup_from_current(void) |
3020 | { | |
3021 | struct obj_cgroup *objcg = NULL; | |
3022 | struct mem_cgroup *memcg; | |
3023 | ||
279c3393 RG |
3024 | if (memcg_kmem_bypass()) |
3025 | return NULL; | |
3026 | ||
bf4f0599 | 3027 | rcu_read_lock(); |
37d5985c RG |
3028 | if (unlikely(active_memcg())) |
3029 | memcg = active_memcg(); | |
bf4f0599 RG |
3030 | else |
3031 | memcg = mem_cgroup_from_task(current); | |
f4840ccf | 3032 | objcg = __get_obj_cgroup_from_memcg(memcg); |
bf4f0599 | 3033 | rcu_read_unlock(); |
f4840ccf JW |
3034 | return objcg; |
3035 | } | |
3036 | ||
074e3e26 | 3037 | struct obj_cgroup *get_obj_cgroup_from_folio(struct folio *folio) |
f4840ccf JW |
3038 | { |
3039 | struct obj_cgroup *objcg; | |
3040 | ||
f7a449f7 | 3041 | if (!memcg_kmem_online()) |
f4840ccf JW |
3042 | return NULL; |
3043 | ||
074e3e26 MWO |
3044 | if (folio_memcg_kmem(folio)) { |
3045 | objcg = __folio_objcg(folio); | |
f4840ccf JW |
3046 | obj_cgroup_get(objcg); |
3047 | } else { | |
3048 | struct mem_cgroup *memcg; | |
bf4f0599 | 3049 | |
f4840ccf | 3050 | rcu_read_lock(); |
074e3e26 | 3051 | memcg = __folio_memcg(folio); |
f4840ccf JW |
3052 | if (memcg) |
3053 | objcg = __get_obj_cgroup_from_memcg(memcg); | |
3054 | else | |
3055 | objcg = NULL; | |
3056 | rcu_read_unlock(); | |
3057 | } | |
bf4f0599 RG |
3058 | return objcg; |
3059 | } | |
3060 | ||
a8c49af3 YA |
3061 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) |
3062 | { | |
3063 | mod_memcg_state(memcg, MEMCG_KMEM, nr_pages); | |
3064 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { | |
3065 | if (nr_pages > 0) | |
3066 | page_counter_charge(&memcg->kmem, nr_pages); | |
3067 | else | |
3068 | page_counter_uncharge(&memcg->kmem, -nr_pages); | |
3069 | } | |
3070 | } | |
3071 | ||
3072 | ||
f1286fae MS |
3073 | /* |
3074 | * obj_cgroup_uncharge_pages: uncharge a number of kernel pages from a objcg | |
3075 | * @objcg: object cgroup to uncharge | |
3076 | * @nr_pages: number of pages to uncharge | |
3077 | */ | |
e74d2259 MS |
3078 | static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, |
3079 | unsigned int nr_pages) | |
3080 | { | |
3081 | struct mem_cgroup *memcg; | |
3082 | ||
3083 | memcg = get_mem_cgroup_from_objcg(objcg); | |
e74d2259 | 3084 | |
a8c49af3 | 3085 | memcg_account_kmem(memcg, -nr_pages); |
f1286fae | 3086 | refill_stock(memcg, nr_pages); |
e74d2259 | 3087 | |
e74d2259 | 3088 | css_put(&memcg->css); |
e74d2259 MS |
3089 | } |
3090 | ||
f1286fae MS |
3091 | /* |
3092 | * obj_cgroup_charge_pages: charge a number of kernel pages to a objcg | |
3093 | * @objcg: object cgroup to charge | |
45264778 | 3094 | * @gfp: reclaim mode |
92d0510c | 3095 | * @nr_pages: number of pages to charge |
45264778 VD |
3096 | * |
3097 | * Returns 0 on success, an error code on failure. | |
3098 | */ | |
f1286fae MS |
3099 | static int obj_cgroup_charge_pages(struct obj_cgroup *objcg, gfp_t gfp, |
3100 | unsigned int nr_pages) | |
7ae1e1d0 | 3101 | { |
f1286fae | 3102 | struct mem_cgroup *memcg; |
7ae1e1d0 GC |
3103 | int ret; |
3104 | ||
f1286fae MS |
3105 | memcg = get_mem_cgroup_from_objcg(objcg); |
3106 | ||
c5c8b16b | 3107 | ret = try_charge_memcg(memcg, gfp, nr_pages); |
52c29b04 | 3108 | if (ret) |
f1286fae | 3109 | goto out; |
52c29b04 | 3110 | |
a8c49af3 | 3111 | memcg_account_kmem(memcg, nr_pages); |
f1286fae MS |
3112 | out: |
3113 | css_put(&memcg->css); | |
4b13f64d | 3114 | |
f1286fae | 3115 | return ret; |
4b13f64d RG |
3116 | } |
3117 | ||
45264778 | 3118 | /** |
f4b00eab | 3119 | * __memcg_kmem_charge_page: charge a kmem page to the current memory cgroup |
45264778 VD |
3120 | * @page: page to charge |
3121 | * @gfp: reclaim mode | |
3122 | * @order: allocation order | |
3123 | * | |
3124 | * Returns 0 on success, an error code on failure. | |
3125 | */ | |
f4b00eab | 3126 | int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) |
7ae1e1d0 | 3127 | { |
b4e0b68f | 3128 | struct obj_cgroup *objcg; |
fcff7d7e | 3129 | int ret = 0; |
7ae1e1d0 | 3130 | |
b4e0b68f MS |
3131 | objcg = get_obj_cgroup_from_current(); |
3132 | if (objcg) { | |
3133 | ret = obj_cgroup_charge_pages(objcg, gfp, 1 << order); | |
4d96ba35 | 3134 | if (!ret) { |
b4e0b68f | 3135 | page->memcg_data = (unsigned long)objcg | |
18b2db3b | 3136 | MEMCG_DATA_KMEM; |
1a3e1f40 | 3137 | return 0; |
4d96ba35 | 3138 | } |
b4e0b68f | 3139 | obj_cgroup_put(objcg); |
c4159a75 | 3140 | } |
d05e83a6 | 3141 | return ret; |
7ae1e1d0 | 3142 | } |
49a18eae | 3143 | |
45264778 | 3144 | /** |
f4b00eab | 3145 | * __memcg_kmem_uncharge_page: uncharge a kmem page |
45264778 VD |
3146 | * @page: page to uncharge |
3147 | * @order: allocation order | |
3148 | */ | |
f4b00eab | 3149 | void __memcg_kmem_uncharge_page(struct page *page, int order) |
7ae1e1d0 | 3150 | { |
1b7e4464 | 3151 | struct folio *folio = page_folio(page); |
b4e0b68f | 3152 | struct obj_cgroup *objcg; |
f3ccb2c4 | 3153 | unsigned int nr_pages = 1 << order; |
7ae1e1d0 | 3154 | |
1b7e4464 | 3155 | if (!folio_memcg_kmem(folio)) |
7ae1e1d0 GC |
3156 | return; |
3157 | ||
1b7e4464 | 3158 | objcg = __folio_objcg(folio); |
b4e0b68f | 3159 | obj_cgroup_uncharge_pages(objcg, nr_pages); |
1b7e4464 | 3160 | folio->memcg_data = 0; |
b4e0b68f | 3161 | obj_cgroup_put(objcg); |
60d3fd32 | 3162 | } |
bf4f0599 | 3163 | |
68ac5b3c WL |
3164 | void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, |
3165 | enum node_stat_item idx, int nr) | |
3166 | { | |
fead2b86 | 3167 | struct memcg_stock_pcp *stock; |
56751146 | 3168 | struct obj_cgroup *old = NULL; |
68ac5b3c WL |
3169 | unsigned long flags; |
3170 | int *bytes; | |
3171 | ||
56751146 | 3172 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3173 | stock = this_cpu_ptr(&memcg_stock); |
3174 | ||
68ac5b3c WL |
3175 | /* |
3176 | * Save vmstat data in stock and skip vmstat array update unless | |
3177 | * accumulating over a page of vmstat data or when pgdat or idx | |
3178 | * changes. | |
3179 | */ | |
3b8abb32 | 3180 | if (READ_ONCE(stock->cached_objcg) != objcg) { |
56751146 | 3181 | old = drain_obj_stock(stock); |
68ac5b3c WL |
3182 | obj_cgroup_get(objcg); |
3183 | stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) | |
3184 | ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; | |
3b8abb32 | 3185 | WRITE_ONCE(stock->cached_objcg, objcg); |
68ac5b3c WL |
3186 | stock->cached_pgdat = pgdat; |
3187 | } else if (stock->cached_pgdat != pgdat) { | |
3188 | /* Flush the existing cached vmstat data */ | |
7fa0dacb WL |
3189 | struct pglist_data *oldpg = stock->cached_pgdat; |
3190 | ||
68ac5b3c | 3191 | if (stock->nr_slab_reclaimable_b) { |
7fa0dacb | 3192 | mod_objcg_mlstate(objcg, oldpg, NR_SLAB_RECLAIMABLE_B, |
68ac5b3c WL |
3193 | stock->nr_slab_reclaimable_b); |
3194 | stock->nr_slab_reclaimable_b = 0; | |
3195 | } | |
3196 | if (stock->nr_slab_unreclaimable_b) { | |
7fa0dacb | 3197 | mod_objcg_mlstate(objcg, oldpg, NR_SLAB_UNRECLAIMABLE_B, |
68ac5b3c WL |
3198 | stock->nr_slab_unreclaimable_b); |
3199 | stock->nr_slab_unreclaimable_b = 0; | |
3200 | } | |
3201 | stock->cached_pgdat = pgdat; | |
3202 | } | |
3203 | ||
3204 | bytes = (idx == NR_SLAB_RECLAIMABLE_B) ? &stock->nr_slab_reclaimable_b | |
3205 | : &stock->nr_slab_unreclaimable_b; | |
3206 | /* | |
3207 | * Even for large object >= PAGE_SIZE, the vmstat data will still be | |
3208 | * cached locally at least once before pushing it out. | |
3209 | */ | |
3210 | if (!*bytes) { | |
3211 | *bytes = nr; | |
3212 | nr = 0; | |
3213 | } else { | |
3214 | *bytes += nr; | |
3215 | if (abs(*bytes) > PAGE_SIZE) { | |
3216 | nr = *bytes; | |
3217 | *bytes = 0; | |
3218 | } else { | |
3219 | nr = 0; | |
3220 | } | |
3221 | } | |
3222 | if (nr) | |
3223 | mod_objcg_mlstate(objcg, pgdat, idx, nr); | |
3224 | ||
56751146 SAS |
3225 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
3226 | if (old) | |
3227 | obj_cgroup_put(old); | |
68ac5b3c WL |
3228 | } |
3229 | ||
bf4f0599 RG |
3230 | static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes) |
3231 | { | |
fead2b86 | 3232 | struct memcg_stock_pcp *stock; |
bf4f0599 RG |
3233 | unsigned long flags; |
3234 | bool ret = false; | |
3235 | ||
56751146 | 3236 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3237 | |
3238 | stock = this_cpu_ptr(&memcg_stock); | |
3b8abb32 | 3239 | if (objcg == READ_ONCE(stock->cached_objcg) && stock->nr_bytes >= nr_bytes) { |
bf4f0599 RG |
3240 | stock->nr_bytes -= nr_bytes; |
3241 | ret = true; | |
3242 | } | |
3243 | ||
56751146 | 3244 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
bf4f0599 RG |
3245 | |
3246 | return ret; | |
3247 | } | |
3248 | ||
56751146 | 3249 | static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) |
bf4f0599 | 3250 | { |
3b8abb32 | 3251 | struct obj_cgroup *old = READ_ONCE(stock->cached_objcg); |
bf4f0599 RG |
3252 | |
3253 | if (!old) | |
56751146 | 3254 | return NULL; |
bf4f0599 RG |
3255 | |
3256 | if (stock->nr_bytes) { | |
3257 | unsigned int nr_pages = stock->nr_bytes >> PAGE_SHIFT; | |
3258 | unsigned int nr_bytes = stock->nr_bytes & (PAGE_SIZE - 1); | |
3259 | ||
af9a3b69 JW |
3260 | if (nr_pages) { |
3261 | struct mem_cgroup *memcg; | |
3262 | ||
3263 | memcg = get_mem_cgroup_from_objcg(old); | |
3264 | ||
3265 | memcg_account_kmem(memcg, -nr_pages); | |
3266 | __refill_stock(memcg, nr_pages); | |
3267 | ||
3268 | css_put(&memcg->css); | |
3269 | } | |
bf4f0599 RG |
3270 | |
3271 | /* | |
3272 | * The leftover is flushed to the centralized per-memcg value. | |
3273 | * On the next attempt to refill obj stock it will be moved | |
3274 | * to a per-cpu stock (probably, on an other CPU), see | |
3275 | * refill_obj_stock(). | |
3276 | * | |
3277 | * How often it's flushed is a trade-off between the memory | |
3278 | * limit enforcement accuracy and potential CPU contention, | |
3279 | * so it might be changed in the future. | |
3280 | */ | |
3281 | atomic_add(nr_bytes, &old->nr_charged_bytes); | |
3282 | stock->nr_bytes = 0; | |
3283 | } | |
3284 | ||
68ac5b3c WL |
3285 | /* |
3286 | * Flush the vmstat data in current stock | |
3287 | */ | |
3288 | if (stock->nr_slab_reclaimable_b || stock->nr_slab_unreclaimable_b) { | |
3289 | if (stock->nr_slab_reclaimable_b) { | |
3290 | mod_objcg_mlstate(old, stock->cached_pgdat, | |
3291 | NR_SLAB_RECLAIMABLE_B, | |
3292 | stock->nr_slab_reclaimable_b); | |
3293 | stock->nr_slab_reclaimable_b = 0; | |
3294 | } | |
3295 | if (stock->nr_slab_unreclaimable_b) { | |
3296 | mod_objcg_mlstate(old, stock->cached_pgdat, | |
3297 | NR_SLAB_UNRECLAIMABLE_B, | |
3298 | stock->nr_slab_unreclaimable_b); | |
3299 | stock->nr_slab_unreclaimable_b = 0; | |
3300 | } | |
3301 | stock->cached_pgdat = NULL; | |
3302 | } | |
3303 | ||
3b8abb32 | 3304 | WRITE_ONCE(stock->cached_objcg, NULL); |
56751146 SAS |
3305 | /* |
3306 | * The `old' objects needs to be released by the caller via | |
3307 | * obj_cgroup_put() outside of memcg_stock_pcp::stock_lock. | |
3308 | */ | |
3309 | return old; | |
bf4f0599 RG |
3310 | } |
3311 | ||
3312 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, | |
3313 | struct mem_cgroup *root_memcg) | |
3314 | { | |
3b8abb32 | 3315 | struct obj_cgroup *objcg = READ_ONCE(stock->cached_objcg); |
bf4f0599 RG |
3316 | struct mem_cgroup *memcg; |
3317 | ||
3b8abb32 RG |
3318 | if (objcg) { |
3319 | memcg = obj_cgroup_memcg(objcg); | |
bf4f0599 RG |
3320 | if (memcg && mem_cgroup_is_descendant(memcg, root_memcg)) |
3321 | return true; | |
3322 | } | |
3323 | ||
3324 | return false; | |
3325 | } | |
3326 | ||
5387c904 WL |
3327 | static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes, |
3328 | bool allow_uncharge) | |
bf4f0599 | 3329 | { |
fead2b86 | 3330 | struct memcg_stock_pcp *stock; |
56751146 | 3331 | struct obj_cgroup *old = NULL; |
bf4f0599 | 3332 | unsigned long flags; |
5387c904 | 3333 | unsigned int nr_pages = 0; |
bf4f0599 | 3334 | |
56751146 | 3335 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3336 | |
3337 | stock = this_cpu_ptr(&memcg_stock); | |
3b8abb32 | 3338 | if (READ_ONCE(stock->cached_objcg) != objcg) { /* reset if necessary */ |
56751146 | 3339 | old = drain_obj_stock(stock); |
bf4f0599 | 3340 | obj_cgroup_get(objcg); |
3b8abb32 | 3341 | WRITE_ONCE(stock->cached_objcg, objcg); |
5387c904 WL |
3342 | stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) |
3343 | ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; | |
3344 | allow_uncharge = true; /* Allow uncharge when objcg changes */ | |
bf4f0599 RG |
3345 | } |
3346 | stock->nr_bytes += nr_bytes; | |
3347 | ||
5387c904 WL |
3348 | if (allow_uncharge && (stock->nr_bytes > PAGE_SIZE)) { |
3349 | nr_pages = stock->nr_bytes >> PAGE_SHIFT; | |
3350 | stock->nr_bytes &= (PAGE_SIZE - 1); | |
3351 | } | |
bf4f0599 | 3352 | |
56751146 SAS |
3353 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
3354 | if (old) | |
3355 | obj_cgroup_put(old); | |
5387c904 WL |
3356 | |
3357 | if (nr_pages) | |
3358 | obj_cgroup_uncharge_pages(objcg, nr_pages); | |
bf4f0599 RG |
3359 | } |
3360 | ||
3361 | int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size) | |
3362 | { | |
bf4f0599 RG |
3363 | unsigned int nr_pages, nr_bytes; |
3364 | int ret; | |
3365 | ||
3366 | if (consume_obj_stock(objcg, size)) | |
3367 | return 0; | |
3368 | ||
3369 | /* | |
5387c904 | 3370 | * In theory, objcg->nr_charged_bytes can have enough |
bf4f0599 | 3371 | * pre-charged bytes to satisfy the allocation. However, |
5387c904 WL |
3372 | * flushing objcg->nr_charged_bytes requires two atomic |
3373 | * operations, and objcg->nr_charged_bytes can't be big. | |
3374 | * The shared objcg->nr_charged_bytes can also become a | |
3375 | * performance bottleneck if all tasks of the same memcg are | |
3376 | * trying to update it. So it's better to ignore it and try | |
3377 | * grab some new pages. The stock's nr_bytes will be flushed to | |
3378 | * objcg->nr_charged_bytes later on when objcg changes. | |
3379 | * | |
3380 | * The stock's nr_bytes may contain enough pre-charged bytes | |
3381 | * to allow one less page from being charged, but we can't rely | |
3382 | * on the pre-charged bytes not being changed outside of | |
3383 | * consume_obj_stock() or refill_obj_stock(). So ignore those | |
3384 | * pre-charged bytes as well when charging pages. To avoid a | |
3385 | * page uncharge right after a page charge, we set the | |
3386 | * allow_uncharge flag to false when calling refill_obj_stock() | |
3387 | * to temporarily allow the pre-charged bytes to exceed the page | |
3388 | * size limit. The maximum reachable value of the pre-charged | |
3389 | * bytes is (sizeof(object) + PAGE_SIZE - 2) if there is no data | |
3390 | * race. | |
bf4f0599 | 3391 | */ |
bf4f0599 RG |
3392 | nr_pages = size >> PAGE_SHIFT; |
3393 | nr_bytes = size & (PAGE_SIZE - 1); | |
3394 | ||
3395 | if (nr_bytes) | |
3396 | nr_pages += 1; | |
3397 | ||
e74d2259 | 3398 | ret = obj_cgroup_charge_pages(objcg, gfp, nr_pages); |
bf4f0599 | 3399 | if (!ret && nr_bytes) |
5387c904 | 3400 | refill_obj_stock(objcg, PAGE_SIZE - nr_bytes, false); |
bf4f0599 | 3401 | |
bf4f0599 RG |
3402 | return ret; |
3403 | } | |
3404 | ||
3405 | void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size) | |
3406 | { | |
5387c904 | 3407 | refill_obj_stock(objcg, size, true); |
bf4f0599 RG |
3408 | } |
3409 | ||
84c07d11 | 3410 | #endif /* CONFIG_MEMCG_KMEM */ |
7ae1e1d0 | 3411 | |
ca3e0214 | 3412 | /* |
be6c8982 | 3413 | * Because page_memcg(head) is not set on tails, set it now. |
ca3e0214 | 3414 | */ |
be6c8982 | 3415 | void split_page_memcg(struct page *head, unsigned int nr) |
ca3e0214 | 3416 | { |
1b7e4464 MWO |
3417 | struct folio *folio = page_folio(head); |
3418 | struct mem_cgroup *memcg = folio_memcg(folio); | |
e94c8a9c | 3419 | int i; |
ca3e0214 | 3420 | |
be6c8982 | 3421 | if (mem_cgroup_disabled() || !memcg) |
3d37c4a9 | 3422 | return; |
b070e65c | 3423 | |
be6c8982 | 3424 | for (i = 1; i < nr; i++) |
1b7e4464 | 3425 | folio_page(folio, i)->memcg_data = folio->memcg_data; |
b4e0b68f | 3426 | |
1b7e4464 MWO |
3427 | if (folio_memcg_kmem(folio)) |
3428 | obj_cgroup_get_many(__folio_objcg(folio), nr - 1); | |
b4e0b68f MS |
3429 | else |
3430 | css_get_many(&memcg->css, nr - 1); | |
ca3e0214 | 3431 | } |
ca3e0214 | 3432 | |
e55b9f96 | 3433 | #ifdef CONFIG_SWAP |
02491447 DN |
3434 | /** |
3435 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
3436 | * @entry: swap entry to be moved | |
3437 | * @from: mem_cgroup which the entry is moved from | |
3438 | * @to: mem_cgroup which the entry is moved to | |
3439 | * | |
3440 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
3441 | * as the mem_cgroup's id of @from. | |
3442 | * | |
3443 | * Returns 0 on success, -EINVAL on failure. | |
3444 | * | |
3e32cb2e | 3445 | * The caller must have charged to @to, IOW, called page_counter_charge() about |
02491447 DN |
3446 | * both res and memsw, and called css_get(). |
3447 | */ | |
3448 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 3449 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
3450 | { |
3451 | unsigned short old_id, new_id; | |
3452 | ||
34c00c31 LZ |
3453 | old_id = mem_cgroup_id(from); |
3454 | new_id = mem_cgroup_id(to); | |
02491447 DN |
3455 | |
3456 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
c9019e9b JW |
3457 | mod_memcg_state(from, MEMCG_SWAP, -1); |
3458 | mod_memcg_state(to, MEMCG_SWAP, 1); | |
02491447 DN |
3459 | return 0; |
3460 | } | |
3461 | return -EINVAL; | |
3462 | } | |
3463 | #else | |
3464 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 3465 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
3466 | { |
3467 | return -EINVAL; | |
3468 | } | |
8c7c6e34 | 3469 | #endif |
d13d1443 | 3470 | |
bbec2e15 | 3471 | static DEFINE_MUTEX(memcg_max_mutex); |
f212ad7c | 3472 | |
bbec2e15 RG |
3473 | static int mem_cgroup_resize_max(struct mem_cgroup *memcg, |
3474 | unsigned long max, bool memsw) | |
628f4235 | 3475 | { |
3e32cb2e | 3476 | bool enlarge = false; |
bb4a7ea2 | 3477 | bool drained = false; |
3e32cb2e | 3478 | int ret; |
c054a78c YZ |
3479 | bool limits_invariant; |
3480 | struct page_counter *counter = memsw ? &memcg->memsw : &memcg->memory; | |
81d39c20 | 3481 | |
3e32cb2e | 3482 | do { |
628f4235 KH |
3483 | if (signal_pending(current)) { |
3484 | ret = -EINTR; | |
3485 | break; | |
3486 | } | |
3e32cb2e | 3487 | |
bbec2e15 | 3488 | mutex_lock(&memcg_max_mutex); |
c054a78c YZ |
3489 | /* |
3490 | * Make sure that the new limit (memsw or memory limit) doesn't | |
bbec2e15 | 3491 | * break our basic invariant rule memory.max <= memsw.max. |
c054a78c | 3492 | */ |
15b42562 | 3493 | limits_invariant = memsw ? max >= READ_ONCE(memcg->memory.max) : |
bbec2e15 | 3494 | max <= memcg->memsw.max; |
c054a78c | 3495 | if (!limits_invariant) { |
bbec2e15 | 3496 | mutex_unlock(&memcg_max_mutex); |
8c7c6e34 | 3497 | ret = -EINVAL; |
8c7c6e34 KH |
3498 | break; |
3499 | } | |
bbec2e15 | 3500 | if (max > counter->max) |
3e32cb2e | 3501 | enlarge = true; |
bbec2e15 RG |
3502 | ret = page_counter_set_max(counter, max); |
3503 | mutex_unlock(&memcg_max_mutex); | |
8c7c6e34 KH |
3504 | |
3505 | if (!ret) | |
3506 | break; | |
3507 | ||
bb4a7ea2 SB |
3508 | if (!drained) { |
3509 | drain_all_stock(memcg); | |
3510 | drained = true; | |
3511 | continue; | |
3512 | } | |
3513 | ||
73b73bac | 3514 | if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, |
55ab834a | 3515 | memsw ? 0 : MEMCG_RECLAIM_MAY_SWAP)) { |
1ab5c056 AR |
3516 | ret = -EBUSY; |
3517 | break; | |
3518 | } | |
3519 | } while (true); | |
3e32cb2e | 3520 | |
3c11ecf4 KH |
3521 | if (!ret && enlarge) |
3522 | memcg_oom_recover(memcg); | |
3e32cb2e | 3523 | |
628f4235 KH |
3524 | return ret; |
3525 | } | |
3526 | ||
ef8f2327 | 3527 | unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, |
0608f43d AM |
3528 | gfp_t gfp_mask, |
3529 | unsigned long *total_scanned) | |
3530 | { | |
3531 | unsigned long nr_reclaimed = 0; | |
ef8f2327 | 3532 | struct mem_cgroup_per_node *mz, *next_mz = NULL; |
0608f43d AM |
3533 | unsigned long reclaimed; |
3534 | int loop = 0; | |
ef8f2327 | 3535 | struct mem_cgroup_tree_per_node *mctz; |
3e32cb2e | 3536 | unsigned long excess; |
0608f43d | 3537 | |
e4dde56c YZ |
3538 | if (lru_gen_enabled()) |
3539 | return 0; | |
3540 | ||
0608f43d AM |
3541 | if (order > 0) |
3542 | return 0; | |
3543 | ||
2ab082ba | 3544 | mctz = soft_limit_tree.rb_tree_per_node[pgdat->node_id]; |
d6507ff5 MH |
3545 | |
3546 | /* | |
3547 | * Do not even bother to check the largest node if the root | |
3548 | * is empty. Do it lockless to prevent lock bouncing. Races | |
3549 | * are acceptable as soft limit is best effort anyway. | |
3550 | */ | |
bfc7228b | 3551 | if (!mctz || RB_EMPTY_ROOT(&mctz->rb_root)) |
d6507ff5 MH |
3552 | return 0; |
3553 | ||
0608f43d AM |
3554 | /* |
3555 | * This loop can run a while, specially if mem_cgroup's continuously | |
3556 | * keep exceeding their soft limit and putting the system under | |
3557 | * pressure | |
3558 | */ | |
3559 | do { | |
3560 | if (next_mz) | |
3561 | mz = next_mz; | |
3562 | else | |
3563 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
3564 | if (!mz) | |
3565 | break; | |
3566 | ||
ef8f2327 | 3567 | reclaimed = mem_cgroup_soft_reclaim(mz->memcg, pgdat, |
d8f65338 | 3568 | gfp_mask, total_scanned); |
0608f43d | 3569 | nr_reclaimed += reclaimed; |
0a31bc97 | 3570 | spin_lock_irq(&mctz->lock); |
0608f43d AM |
3571 | |
3572 | /* | |
3573 | * If we failed to reclaim anything from this memory cgroup | |
3574 | * it is time to move on to the next cgroup | |
3575 | */ | |
3576 | next_mz = NULL; | |
bc2f2e7f VD |
3577 | if (!reclaimed) |
3578 | next_mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
3579 | ||
3e32cb2e | 3580 | excess = soft_limit_excess(mz->memcg); |
0608f43d AM |
3581 | /* |
3582 | * One school of thought says that we should not add | |
3583 | * back the node to the tree if reclaim returns 0. | |
3584 | * But our reclaim could return 0, simply because due | |
3585 | * to priority we are exposing a smaller subset of | |
3586 | * memory to reclaim from. Consider this as a longer | |
3587 | * term TODO. | |
3588 | */ | |
3589 | /* If excess == 0, no tree ops */ | |
cf2c8127 | 3590 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 3591 | spin_unlock_irq(&mctz->lock); |
0608f43d AM |
3592 | css_put(&mz->memcg->css); |
3593 | loop++; | |
3594 | /* | |
3595 | * Could not reclaim anything and there are no more | |
3596 | * mem cgroups to try or we seem to be looping without | |
3597 | * reclaiming anything. | |
3598 | */ | |
3599 | if (!nr_reclaimed && | |
3600 | (next_mz == NULL || | |
3601 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
3602 | break; | |
3603 | } while (!nr_reclaimed); | |
3604 | if (next_mz) | |
3605 | css_put(&next_mz->memcg->css); | |
3606 | return nr_reclaimed; | |
3607 | } | |
3608 | ||
c26251f9 | 3609 | /* |
51038171 | 3610 | * Reclaims as many pages from the given memcg as possible. |
c26251f9 MH |
3611 | * |
3612 | * Caller is responsible for holding css reference for memcg. | |
3613 | */ | |
3614 | static int mem_cgroup_force_empty(struct mem_cgroup *memcg) | |
3615 | { | |
d977aa93 | 3616 | int nr_retries = MAX_RECLAIM_RETRIES; |
c26251f9 | 3617 | |
c1e862c1 KH |
3618 | /* we call try-to-free pages for make this cgroup empty */ |
3619 | lru_add_drain_all(); | |
d12c60f6 JS |
3620 | |
3621 | drain_all_stock(memcg); | |
3622 | ||
f817ed48 | 3623 | /* try to free all pages in this cgroup */ |
3e32cb2e | 3624 | while (nr_retries && page_counter_read(&memcg->memory)) { |
c26251f9 MH |
3625 | if (signal_pending(current)) |
3626 | return -EINTR; | |
3627 | ||
73b73bac | 3628 | if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, |
55ab834a | 3629 | MEMCG_RECLAIM_MAY_SWAP)) |
f817ed48 | 3630 | nr_retries--; |
f817ed48 | 3631 | } |
ab5196c2 MH |
3632 | |
3633 | return 0; | |
cc847582 KH |
3634 | } |
3635 | ||
6770c64e TH |
3636 | static ssize_t mem_cgroup_force_empty_write(struct kernfs_open_file *of, |
3637 | char *buf, size_t nbytes, | |
3638 | loff_t off) | |
c1e862c1 | 3639 | { |
6770c64e | 3640 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
c26251f9 | 3641 | |
d8423011 MH |
3642 | if (mem_cgroup_is_root(memcg)) |
3643 | return -EINVAL; | |
6770c64e | 3644 | return mem_cgroup_force_empty(memcg) ?: nbytes; |
c1e862c1 KH |
3645 | } |
3646 | ||
182446d0 TH |
3647 | static u64 mem_cgroup_hierarchy_read(struct cgroup_subsys_state *css, |
3648 | struct cftype *cft) | |
18f59ea7 | 3649 | { |
bef8620c | 3650 | return 1; |
18f59ea7 BS |
3651 | } |
3652 | ||
182446d0 TH |
3653 | static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css, |
3654 | struct cftype *cft, u64 val) | |
18f59ea7 | 3655 | { |
bef8620c | 3656 | if (val == 1) |
0b8f73e1 | 3657 | return 0; |
567fb435 | 3658 | |
bef8620c RG |
3659 | pr_warn_once("Non-hierarchical mode is deprecated. " |
3660 | "Please report your usecase to linux-mm@kvack.org if you " | |
3661 | "depend on this functionality.\n"); | |
567fb435 | 3662 | |
bef8620c | 3663 | return -EINVAL; |
18f59ea7 BS |
3664 | } |
3665 | ||
6f646156 | 3666 | static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) |
ce00a967 | 3667 | { |
42a30035 | 3668 | unsigned long val; |
ce00a967 | 3669 | |
3e32cb2e | 3670 | if (mem_cgroup_is_root(memcg)) { |
a2174e95 | 3671 | /* |
f82a7a86 YA |
3672 | * Approximate root's usage from global state. This isn't |
3673 | * perfect, but the root usage was always an approximation. | |
a2174e95 | 3674 | */ |
f82a7a86 YA |
3675 | val = global_node_page_state(NR_FILE_PAGES) + |
3676 | global_node_page_state(NR_ANON_MAPPED); | |
42a30035 | 3677 | if (swap) |
f82a7a86 | 3678 | val += total_swap_pages - get_nr_swap_pages(); |
3e32cb2e | 3679 | } else { |
ce00a967 | 3680 | if (!swap) |
3e32cb2e | 3681 | val = page_counter_read(&memcg->memory); |
ce00a967 | 3682 | else |
3e32cb2e | 3683 | val = page_counter_read(&memcg->memsw); |
ce00a967 | 3684 | } |
c12176d3 | 3685 | return val; |
ce00a967 JW |
3686 | } |
3687 | ||
3e32cb2e JW |
3688 | enum { |
3689 | RES_USAGE, | |
3690 | RES_LIMIT, | |
3691 | RES_MAX_USAGE, | |
3692 | RES_FAILCNT, | |
3693 | RES_SOFT_LIMIT, | |
3694 | }; | |
ce00a967 | 3695 | |
791badbd | 3696 | static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css, |
05b84301 | 3697 | struct cftype *cft) |
8cdea7c0 | 3698 | { |
182446d0 | 3699 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3e32cb2e | 3700 | struct page_counter *counter; |
af36f906 | 3701 | |
3e32cb2e | 3702 | switch (MEMFILE_TYPE(cft->private)) { |
8c7c6e34 | 3703 | case _MEM: |
3e32cb2e JW |
3704 | counter = &memcg->memory; |
3705 | break; | |
8c7c6e34 | 3706 | case _MEMSWAP: |
3e32cb2e JW |
3707 | counter = &memcg->memsw; |
3708 | break; | |
510fc4e1 | 3709 | case _KMEM: |
3e32cb2e | 3710 | counter = &memcg->kmem; |
510fc4e1 | 3711 | break; |
d55f90bf | 3712 | case _TCP: |
0db15298 | 3713 | counter = &memcg->tcpmem; |
d55f90bf | 3714 | break; |
8c7c6e34 KH |
3715 | default: |
3716 | BUG(); | |
8c7c6e34 | 3717 | } |
3e32cb2e JW |
3718 | |
3719 | switch (MEMFILE_ATTR(cft->private)) { | |
3720 | case RES_USAGE: | |
3721 | if (counter == &memcg->memory) | |
c12176d3 | 3722 | return (u64)mem_cgroup_usage(memcg, false) * PAGE_SIZE; |
3e32cb2e | 3723 | if (counter == &memcg->memsw) |
c12176d3 | 3724 | return (u64)mem_cgroup_usage(memcg, true) * PAGE_SIZE; |
3e32cb2e JW |
3725 | return (u64)page_counter_read(counter) * PAGE_SIZE; |
3726 | case RES_LIMIT: | |
bbec2e15 | 3727 | return (u64)counter->max * PAGE_SIZE; |
3e32cb2e JW |
3728 | case RES_MAX_USAGE: |
3729 | return (u64)counter->watermark * PAGE_SIZE; | |
3730 | case RES_FAILCNT: | |
3731 | return counter->failcnt; | |
3732 | case RES_SOFT_LIMIT: | |
2178e20c | 3733 | return (u64)READ_ONCE(memcg->soft_limit) * PAGE_SIZE; |
3e32cb2e JW |
3734 | default: |
3735 | BUG(); | |
3736 | } | |
8cdea7c0 | 3737 | } |
510fc4e1 | 3738 | |
6b0ba2ab FS |
3739 | /* |
3740 | * This function doesn't do anything useful. Its only job is to provide a read | |
3741 | * handler for a file so that cgroup_file_mode() will add read permissions. | |
3742 | */ | |
3743 | static int mem_cgroup_dummy_seq_show(__always_unused struct seq_file *m, | |
3744 | __always_unused void *v) | |
3745 | { | |
3746 | return -EINVAL; | |
3747 | } | |
3748 | ||
84c07d11 | 3749 | #ifdef CONFIG_MEMCG_KMEM |
567e9ab2 | 3750 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
d6441637 | 3751 | { |
bf4f0599 | 3752 | struct obj_cgroup *objcg; |
d6441637 | 3753 | |
9c94bef9 | 3754 | if (mem_cgroup_kmem_disabled()) |
b313aeee VD |
3755 | return 0; |
3756 | ||
da0efe30 MS |
3757 | if (unlikely(mem_cgroup_is_root(memcg))) |
3758 | return 0; | |
d6441637 | 3759 | |
bf4f0599 | 3760 | objcg = obj_cgroup_alloc(); |
f9c69d63 | 3761 | if (!objcg) |
bf4f0599 | 3762 | return -ENOMEM; |
f9c69d63 | 3763 | |
bf4f0599 RG |
3764 | objcg->memcg = memcg; |
3765 | rcu_assign_pointer(memcg->objcg, objcg); | |
3766 | ||
f7a449f7 | 3767 | static_branch_enable(&memcg_kmem_online_key); |
d648bcc7 | 3768 | |
f9c69d63 | 3769 | memcg->kmemcg_id = memcg->id.id; |
0b8f73e1 JW |
3770 | |
3771 | return 0; | |
d6441637 VD |
3772 | } |
3773 | ||
8e0a8912 JW |
3774 | static void memcg_offline_kmem(struct mem_cgroup *memcg) |
3775 | { | |
64268868 | 3776 | struct mem_cgroup *parent; |
8e0a8912 | 3777 | |
9c94bef9 | 3778 | if (mem_cgroup_kmem_disabled()) |
da0efe30 MS |
3779 | return; |
3780 | ||
3781 | if (unlikely(mem_cgroup_is_root(memcg))) | |
8e0a8912 | 3782 | return; |
9855609b | 3783 | |
8e0a8912 JW |
3784 | parent = parent_mem_cgroup(memcg); |
3785 | if (!parent) | |
3786 | parent = root_mem_cgroup; | |
3787 | ||
bf4f0599 | 3788 | memcg_reparent_objcgs(memcg, parent); |
fb2f2b0a | 3789 | |
8e0a8912 | 3790 | /* |
64268868 MS |
3791 | * After we have finished memcg_reparent_objcgs(), all list_lrus |
3792 | * corresponding to this cgroup are guaranteed to remain empty. | |
3793 | * The ordering is imposed by list_lru_node->lock taken by | |
1f391eb2 | 3794 | * memcg_reparent_list_lrus(). |
8e0a8912 | 3795 | */ |
1f391eb2 | 3796 | memcg_reparent_list_lrus(memcg, parent); |
8e0a8912 | 3797 | } |
d6441637 | 3798 | #else |
0b8f73e1 | 3799 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
127424c8 JW |
3800 | { |
3801 | return 0; | |
3802 | } | |
3803 | static void memcg_offline_kmem(struct mem_cgroup *memcg) | |
3804 | { | |
3805 | } | |
84c07d11 | 3806 | #endif /* CONFIG_MEMCG_KMEM */ |
127424c8 | 3807 | |
bbec2e15 | 3808 | static int memcg_update_tcp_max(struct mem_cgroup *memcg, unsigned long max) |
d55f90bf VD |
3809 | { |
3810 | int ret; | |
3811 | ||
bbec2e15 | 3812 | mutex_lock(&memcg_max_mutex); |
d55f90bf | 3813 | |
bbec2e15 | 3814 | ret = page_counter_set_max(&memcg->tcpmem, max); |
d55f90bf VD |
3815 | if (ret) |
3816 | goto out; | |
3817 | ||
0db15298 | 3818 | if (!memcg->tcpmem_active) { |
d55f90bf VD |
3819 | /* |
3820 | * The active flag needs to be written after the static_key | |
3821 | * update. This is what guarantees that the socket activation | |
2d758073 JW |
3822 | * function is the last one to run. See mem_cgroup_sk_alloc() |
3823 | * for details, and note that we don't mark any socket as | |
3824 | * belonging to this memcg until that flag is up. | |
d55f90bf VD |
3825 | * |
3826 | * We need to do this, because static_keys will span multiple | |
3827 | * sites, but we can't control their order. If we mark a socket | |
3828 | * as accounted, but the accounting functions are not patched in | |
3829 | * yet, we'll lose accounting. | |
3830 | * | |
2d758073 | 3831 | * We never race with the readers in mem_cgroup_sk_alloc(), |
d55f90bf VD |
3832 | * because when this value change, the code to process it is not |
3833 | * patched in yet. | |
3834 | */ | |
3835 | static_branch_inc(&memcg_sockets_enabled_key); | |
0db15298 | 3836 | memcg->tcpmem_active = true; |
d55f90bf VD |
3837 | } |
3838 | out: | |
bbec2e15 | 3839 | mutex_unlock(&memcg_max_mutex); |
d55f90bf VD |
3840 | return ret; |
3841 | } | |
d55f90bf | 3842 | |
628f4235 KH |
3843 | /* |
3844 | * The user of this function is... | |
3845 | * RES_LIMIT. | |
3846 | */ | |
451af504 TH |
3847 | static ssize_t mem_cgroup_write(struct kernfs_open_file *of, |
3848 | char *buf, size_t nbytes, loff_t off) | |
8cdea7c0 | 3849 | { |
451af504 | 3850 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 3851 | unsigned long nr_pages; |
628f4235 KH |
3852 | int ret; |
3853 | ||
451af504 | 3854 | buf = strstrip(buf); |
650c5e56 | 3855 | ret = page_counter_memparse(buf, "-1", &nr_pages); |
3e32cb2e JW |
3856 | if (ret) |
3857 | return ret; | |
af36f906 | 3858 | |
3e32cb2e | 3859 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
628f4235 | 3860 | case RES_LIMIT: |
4b3bde4c BS |
3861 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
3862 | ret = -EINVAL; | |
3863 | break; | |
3864 | } | |
3e32cb2e JW |
3865 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
3866 | case _MEM: | |
bbec2e15 | 3867 | ret = mem_cgroup_resize_max(memcg, nr_pages, false); |
8c7c6e34 | 3868 | break; |
3e32cb2e | 3869 | case _MEMSWAP: |
bbec2e15 | 3870 | ret = mem_cgroup_resize_max(memcg, nr_pages, true); |
296c81d8 | 3871 | break; |
4597648f MH |
3872 | case _KMEM: |
3873 | pr_warn_once("kmem.limit_in_bytes is deprecated and will be removed. " | |
3874 | "Writing any value to this file has no effect. " | |
3875 | "Please report your usecase to linux-mm@kvack.org if you " | |
3876 | "depend on this functionality.\n"); | |
3877 | ret = 0; | |
3878 | break; | |
d55f90bf | 3879 | case _TCP: |
bbec2e15 | 3880 | ret = memcg_update_tcp_max(memcg, nr_pages); |
d55f90bf | 3881 | break; |
3e32cb2e | 3882 | } |
296c81d8 | 3883 | break; |
3e32cb2e | 3884 | case RES_SOFT_LIMIT: |
2343e88d SAS |
3885 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) { |
3886 | ret = -EOPNOTSUPP; | |
3887 | } else { | |
2178e20c | 3888 | WRITE_ONCE(memcg->soft_limit, nr_pages); |
2343e88d SAS |
3889 | ret = 0; |
3890 | } | |
628f4235 KH |
3891 | break; |
3892 | } | |
451af504 | 3893 | return ret ?: nbytes; |
8cdea7c0 BS |
3894 | } |
3895 | ||
6770c64e TH |
3896 | static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf, |
3897 | size_t nbytes, loff_t off) | |
c84872e1 | 3898 | { |
6770c64e | 3899 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 3900 | struct page_counter *counter; |
c84872e1 | 3901 | |
3e32cb2e JW |
3902 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
3903 | case _MEM: | |
3904 | counter = &memcg->memory; | |
3905 | break; | |
3906 | case _MEMSWAP: | |
3907 | counter = &memcg->memsw; | |
3908 | break; | |
3909 | case _KMEM: | |
3910 | counter = &memcg->kmem; | |
3911 | break; | |
d55f90bf | 3912 | case _TCP: |
0db15298 | 3913 | counter = &memcg->tcpmem; |
d55f90bf | 3914 | break; |
3e32cb2e JW |
3915 | default: |
3916 | BUG(); | |
3917 | } | |
af36f906 | 3918 | |
3e32cb2e | 3919 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
29f2a4da | 3920 | case RES_MAX_USAGE: |
3e32cb2e | 3921 | page_counter_reset_watermark(counter); |
29f2a4da PE |
3922 | break; |
3923 | case RES_FAILCNT: | |
3e32cb2e | 3924 | counter->failcnt = 0; |
29f2a4da | 3925 | break; |
3e32cb2e JW |
3926 | default: |
3927 | BUG(); | |
29f2a4da | 3928 | } |
f64c3f54 | 3929 | |
6770c64e | 3930 | return nbytes; |
c84872e1 PE |
3931 | } |
3932 | ||
182446d0 | 3933 | static u64 mem_cgroup_move_charge_read(struct cgroup_subsys_state *css, |
7dc74be0 DN |
3934 | struct cftype *cft) |
3935 | { | |
182446d0 | 3936 | return mem_cgroup_from_css(css)->move_charge_at_immigrate; |
7dc74be0 DN |
3937 | } |
3938 | ||
02491447 | 3939 | #ifdef CONFIG_MMU |
182446d0 | 3940 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
7dc74be0 DN |
3941 | struct cftype *cft, u64 val) |
3942 | { | |
182446d0 | 3943 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
7dc74be0 | 3944 | |
da34a848 JW |
3945 | pr_warn_once("Cgroup memory moving (move_charge_at_immigrate) is deprecated. " |
3946 | "Please report your usecase to linux-mm@kvack.org if you " | |
3947 | "depend on this functionality.\n"); | |
3948 | ||
1dfab5ab | 3949 | if (val & ~MOVE_MASK) |
7dc74be0 | 3950 | return -EINVAL; |
ee5e8472 | 3951 | |
7dc74be0 | 3952 | /* |
ee5e8472 GC |
3953 | * No kind of locking is needed in here, because ->can_attach() will |
3954 | * check this value once in the beginning of the process, and then carry | |
3955 | * on with stale data. This means that changes to this value will only | |
3956 | * affect task migrations starting after the change. | |
7dc74be0 | 3957 | */ |
c0ff4b85 | 3958 | memcg->move_charge_at_immigrate = val; |
7dc74be0 DN |
3959 | return 0; |
3960 | } | |
02491447 | 3961 | #else |
182446d0 | 3962 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
02491447 DN |
3963 | struct cftype *cft, u64 val) |
3964 | { | |
3965 | return -ENOSYS; | |
3966 | } | |
3967 | #endif | |
7dc74be0 | 3968 | |
406eb0c9 | 3969 | #ifdef CONFIG_NUMA |
113b7dfd JW |
3970 | |
3971 | #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE)) | |
3972 | #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON)) | |
3973 | #define LRU_ALL ((1 << NR_LRU_LISTS) - 1) | |
3974 | ||
3975 | static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, | |
dd8657b6 | 3976 | int nid, unsigned int lru_mask, bool tree) |
113b7dfd | 3977 | { |
867e5e1d | 3978 | struct lruvec *lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); |
113b7dfd JW |
3979 | unsigned long nr = 0; |
3980 | enum lru_list lru; | |
3981 | ||
3982 | VM_BUG_ON((unsigned)nid >= nr_node_ids); | |
3983 | ||
3984 | for_each_lru(lru) { | |
3985 | if (!(BIT(lru) & lru_mask)) | |
3986 | continue; | |
dd8657b6 SB |
3987 | if (tree) |
3988 | nr += lruvec_page_state(lruvec, NR_LRU_BASE + lru); | |
3989 | else | |
3990 | nr += lruvec_page_state_local(lruvec, NR_LRU_BASE + lru); | |
113b7dfd JW |
3991 | } |
3992 | return nr; | |
3993 | } | |
3994 | ||
3995 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, | |
dd8657b6 SB |
3996 | unsigned int lru_mask, |
3997 | bool tree) | |
113b7dfd JW |
3998 | { |
3999 | unsigned long nr = 0; | |
4000 | enum lru_list lru; | |
4001 | ||
4002 | for_each_lru(lru) { | |
4003 | if (!(BIT(lru) & lru_mask)) | |
4004 | continue; | |
dd8657b6 SB |
4005 | if (tree) |
4006 | nr += memcg_page_state(memcg, NR_LRU_BASE + lru); | |
4007 | else | |
4008 | nr += memcg_page_state_local(memcg, NR_LRU_BASE + lru); | |
113b7dfd JW |
4009 | } |
4010 | return nr; | |
4011 | } | |
4012 | ||
2da8ca82 | 4013 | static int memcg_numa_stat_show(struct seq_file *m, void *v) |
406eb0c9 | 4014 | { |
25485de6 GT |
4015 | struct numa_stat { |
4016 | const char *name; | |
4017 | unsigned int lru_mask; | |
4018 | }; | |
4019 | ||
4020 | static const struct numa_stat stats[] = { | |
4021 | { "total", LRU_ALL }, | |
4022 | { "file", LRU_ALL_FILE }, | |
4023 | { "anon", LRU_ALL_ANON }, | |
4024 | { "unevictable", BIT(LRU_UNEVICTABLE) }, | |
4025 | }; | |
4026 | const struct numa_stat *stat; | |
406eb0c9 | 4027 | int nid; |
aa9694bb | 4028 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
406eb0c9 | 4029 | |
fd25a9e0 | 4030 | mem_cgroup_flush_stats(); |
2d146aa3 | 4031 | |
25485de6 | 4032 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
dd8657b6 SB |
4033 | seq_printf(m, "%s=%lu", stat->name, |
4034 | mem_cgroup_nr_lru_pages(memcg, stat->lru_mask, | |
4035 | false)); | |
4036 | for_each_node_state(nid, N_MEMORY) | |
4037 | seq_printf(m, " N%d=%lu", nid, | |
4038 | mem_cgroup_node_nr_lru_pages(memcg, nid, | |
4039 | stat->lru_mask, false)); | |
25485de6 | 4040 | seq_putc(m, '\n'); |
406eb0c9 | 4041 | } |
406eb0c9 | 4042 | |
071aee13 | 4043 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
dd8657b6 SB |
4044 | |
4045 | seq_printf(m, "hierarchical_%s=%lu", stat->name, | |
4046 | mem_cgroup_nr_lru_pages(memcg, stat->lru_mask, | |
4047 | true)); | |
4048 | for_each_node_state(nid, N_MEMORY) | |
4049 | seq_printf(m, " N%d=%lu", nid, | |
4050 | mem_cgroup_node_nr_lru_pages(memcg, nid, | |
4051 | stat->lru_mask, true)); | |
071aee13 | 4052 | seq_putc(m, '\n'); |
406eb0c9 | 4053 | } |
406eb0c9 | 4054 | |
406eb0c9 YH |
4055 | return 0; |
4056 | } | |
4057 | #endif /* CONFIG_NUMA */ | |
4058 | ||
c8713d0b | 4059 | static const unsigned int memcg1_stats[] = { |
0d1c2072 | 4060 | NR_FILE_PAGES, |
be5d0a74 | 4061 | NR_ANON_MAPPED, |
468c3982 JW |
4062 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
4063 | NR_ANON_THPS, | |
4064 | #endif | |
c8713d0b JW |
4065 | NR_SHMEM, |
4066 | NR_FILE_MAPPED, | |
4067 | NR_FILE_DIRTY, | |
4068 | NR_WRITEBACK, | |
e09b0b61 YS |
4069 | WORKINGSET_REFAULT_ANON, |
4070 | WORKINGSET_REFAULT_FILE, | |
72a14e82 | 4071 | #ifdef CONFIG_SWAP |
c8713d0b | 4072 | MEMCG_SWAP, |
72a14e82 LS |
4073 | NR_SWAPCACHE, |
4074 | #endif | |
c8713d0b JW |
4075 | }; |
4076 | ||
4077 | static const char *const memcg1_stat_names[] = { | |
4078 | "cache", | |
4079 | "rss", | |
468c3982 | 4080 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
c8713d0b | 4081 | "rss_huge", |
468c3982 | 4082 | #endif |
c8713d0b JW |
4083 | "shmem", |
4084 | "mapped_file", | |
4085 | "dirty", | |
4086 | "writeback", | |
e09b0b61 YS |
4087 | "workingset_refault_anon", |
4088 | "workingset_refault_file", | |
72a14e82 | 4089 | #ifdef CONFIG_SWAP |
c8713d0b | 4090 | "swap", |
72a14e82 LS |
4091 | "swapcached", |
4092 | #endif | |
c8713d0b JW |
4093 | }; |
4094 | ||
df0e53d0 | 4095 | /* Universal VM events cgroup1 shows, original sort order */ |
8dd53fd3 | 4096 | static const unsigned int memcg1_events[] = { |
df0e53d0 JW |
4097 | PGPGIN, |
4098 | PGPGOUT, | |
4099 | PGFAULT, | |
4100 | PGMAJFAULT, | |
4101 | }; | |
4102 | ||
dddb44ff | 4103 | static void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) |
d2ceb9b7 | 4104 | { |
3e32cb2e | 4105 | unsigned long memory, memsw; |
af7c4b0e JW |
4106 | struct mem_cgroup *mi; |
4107 | unsigned int i; | |
406eb0c9 | 4108 | |
71cd3113 | 4109 | BUILD_BUG_ON(ARRAY_SIZE(memcg1_stat_names) != ARRAY_SIZE(memcg1_stats)); |
70bc068c | 4110 | |
fd25a9e0 | 4111 | mem_cgroup_flush_stats(); |
2d146aa3 | 4112 | |
71cd3113 | 4113 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
468c3982 JW |
4114 | unsigned long nr; |
4115 | ||
468c3982 | 4116 | nr = memcg_page_state_local(memcg, memcg1_stats[i]); |
dddb44ff | 4117 | seq_buf_printf(s, "%s %lu\n", memcg1_stat_names[i], |
e09b0b61 | 4118 | nr * memcg_page_state_unit(memcg1_stats[i])); |
1dd3a273 | 4119 | } |
7b854121 | 4120 | |
df0e53d0 | 4121 | for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) |
dddb44ff YA |
4122 | seq_buf_printf(s, "%s %lu\n", vm_event_name(memcg1_events[i]), |
4123 | memcg_events_local(memcg, memcg1_events[i])); | |
af7c4b0e JW |
4124 | |
4125 | for (i = 0; i < NR_LRU_LISTS; i++) | |
dddb44ff YA |
4126 | seq_buf_printf(s, "%s %lu\n", lru_list_name(i), |
4127 | memcg_page_state_local(memcg, NR_LRU_BASE + i) * | |
4128 | PAGE_SIZE); | |
af7c4b0e | 4129 | |
14067bb3 | 4130 | /* Hierarchical information */ |
3e32cb2e JW |
4131 | memory = memsw = PAGE_COUNTER_MAX; |
4132 | for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) { | |
15b42562 CD |
4133 | memory = min(memory, READ_ONCE(mi->memory.max)); |
4134 | memsw = min(memsw, READ_ONCE(mi->memsw.max)); | |
fee7b548 | 4135 | } |
dddb44ff YA |
4136 | seq_buf_printf(s, "hierarchical_memory_limit %llu\n", |
4137 | (u64)memory * PAGE_SIZE); | |
840ea53a LS |
4138 | seq_buf_printf(s, "hierarchical_memsw_limit %llu\n", |
4139 | (u64)memsw * PAGE_SIZE); | |
7f016ee8 | 4140 | |
8de7ecc6 | 4141 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
7de2e9f1 | 4142 | unsigned long nr; |
4143 | ||
7de2e9f1 | 4144 | nr = memcg_page_state(memcg, memcg1_stats[i]); |
dddb44ff | 4145 | seq_buf_printf(s, "total_%s %llu\n", memcg1_stat_names[i], |
e09b0b61 | 4146 | (u64)nr * memcg_page_state_unit(memcg1_stats[i])); |
af7c4b0e JW |
4147 | } |
4148 | ||
8de7ecc6 | 4149 | for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) |
dddb44ff YA |
4150 | seq_buf_printf(s, "total_%s %llu\n", |
4151 | vm_event_name(memcg1_events[i]), | |
4152 | (u64)memcg_events(memcg, memcg1_events[i])); | |
af7c4b0e | 4153 | |
8de7ecc6 | 4154 | for (i = 0; i < NR_LRU_LISTS; i++) |
dddb44ff YA |
4155 | seq_buf_printf(s, "total_%s %llu\n", lru_list_name(i), |
4156 | (u64)memcg_page_state(memcg, NR_LRU_BASE + i) * | |
4157 | PAGE_SIZE); | |
14067bb3 | 4158 | |
7f016ee8 | 4159 | #ifdef CONFIG_DEBUG_VM |
7f016ee8 | 4160 | { |
ef8f2327 MG |
4161 | pg_data_t *pgdat; |
4162 | struct mem_cgroup_per_node *mz; | |
1431d4d1 JW |
4163 | unsigned long anon_cost = 0; |
4164 | unsigned long file_cost = 0; | |
7f016ee8 | 4165 | |
ef8f2327 | 4166 | for_each_online_pgdat(pgdat) { |
a3747b53 | 4167 | mz = memcg->nodeinfo[pgdat->node_id]; |
7f016ee8 | 4168 | |
1431d4d1 JW |
4169 | anon_cost += mz->lruvec.anon_cost; |
4170 | file_cost += mz->lruvec.file_cost; | |
ef8f2327 | 4171 | } |
dddb44ff YA |
4172 | seq_buf_printf(s, "anon_cost %lu\n", anon_cost); |
4173 | seq_buf_printf(s, "file_cost %lu\n", file_cost); | |
7f016ee8 KM |
4174 | } |
4175 | #endif | |
d2ceb9b7 KH |
4176 | } |
4177 | ||
182446d0 TH |
4178 | static u64 mem_cgroup_swappiness_read(struct cgroup_subsys_state *css, |
4179 | struct cftype *cft) | |
a7885eb8 | 4180 | { |
182446d0 | 4181 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 4182 | |
1f4c025b | 4183 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
4184 | } |
4185 | ||
182446d0 TH |
4186 | static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, |
4187 | struct cftype *cft, u64 val) | |
a7885eb8 | 4188 | { |
182446d0 | 4189 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 4190 | |
37bc3cb9 | 4191 | if (val > 200) |
a7885eb8 KM |
4192 | return -EINVAL; |
4193 | ||
a4792030 | 4194 | if (!mem_cgroup_is_root(memcg)) |
82b3aa26 | 4195 | WRITE_ONCE(memcg->swappiness, val); |
3dae7fec | 4196 | else |
82b3aa26 | 4197 | WRITE_ONCE(vm_swappiness, val); |
068b38c1 | 4198 | |
a7885eb8 KM |
4199 | return 0; |
4200 | } | |
4201 | ||
2e72b634 KS |
4202 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
4203 | { | |
4204 | struct mem_cgroup_threshold_ary *t; | |
3e32cb2e | 4205 | unsigned long usage; |
2e72b634 KS |
4206 | int i; |
4207 | ||
4208 | rcu_read_lock(); | |
4209 | if (!swap) | |
2c488db2 | 4210 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 4211 | else |
2c488db2 | 4212 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
4213 | |
4214 | if (!t) | |
4215 | goto unlock; | |
4216 | ||
ce00a967 | 4217 | usage = mem_cgroup_usage(memcg, swap); |
2e72b634 KS |
4218 | |
4219 | /* | |
748dad36 | 4220 | * current_threshold points to threshold just below or equal to usage. |
2e72b634 KS |
4221 | * If it's not true, a threshold was crossed after last |
4222 | * call of __mem_cgroup_threshold(). | |
4223 | */ | |
5407a562 | 4224 | i = t->current_threshold; |
2e72b634 KS |
4225 | |
4226 | /* | |
4227 | * Iterate backward over array of thresholds starting from | |
4228 | * current_threshold and check if a threshold is crossed. | |
4229 | * If none of thresholds below usage is crossed, we read | |
4230 | * only one element of the array here. | |
4231 | */ | |
4232 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
4233 | eventfd_signal(t->entries[i].eventfd, 1); | |
4234 | ||
4235 | /* i = current_threshold + 1 */ | |
4236 | i++; | |
4237 | ||
4238 | /* | |
4239 | * Iterate forward over array of thresholds starting from | |
4240 | * current_threshold+1 and check if a threshold is crossed. | |
4241 | * If none of thresholds above usage is crossed, we read | |
4242 | * only one element of the array here. | |
4243 | */ | |
4244 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
4245 | eventfd_signal(t->entries[i].eventfd, 1); | |
4246 | ||
4247 | /* Update current_threshold */ | |
5407a562 | 4248 | t->current_threshold = i - 1; |
2e72b634 KS |
4249 | unlock: |
4250 | rcu_read_unlock(); | |
4251 | } | |
4252 | ||
4253 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
4254 | { | |
ad4ca5f4 KS |
4255 | while (memcg) { |
4256 | __mem_cgroup_threshold(memcg, false); | |
7941d214 | 4257 | if (do_memsw_account()) |
ad4ca5f4 KS |
4258 | __mem_cgroup_threshold(memcg, true); |
4259 | ||
4260 | memcg = parent_mem_cgroup(memcg); | |
4261 | } | |
2e72b634 KS |
4262 | } |
4263 | ||
4264 | static int compare_thresholds(const void *a, const void *b) | |
4265 | { | |
4266 | const struct mem_cgroup_threshold *_a = a; | |
4267 | const struct mem_cgroup_threshold *_b = b; | |
4268 | ||
2bff24a3 GT |
4269 | if (_a->threshold > _b->threshold) |
4270 | return 1; | |
4271 | ||
4272 | if (_a->threshold < _b->threshold) | |
4273 | return -1; | |
4274 | ||
4275 | return 0; | |
2e72b634 KS |
4276 | } |
4277 | ||
c0ff4b85 | 4278 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg) |
9490ff27 KH |
4279 | { |
4280 | struct mem_cgroup_eventfd_list *ev; | |
4281 | ||
2bcf2e92 MH |
4282 | spin_lock(&memcg_oom_lock); |
4283 | ||
c0ff4b85 | 4284 | list_for_each_entry(ev, &memcg->oom_notify, list) |
9490ff27 | 4285 | eventfd_signal(ev->eventfd, 1); |
2bcf2e92 MH |
4286 | |
4287 | spin_unlock(&memcg_oom_lock); | |
9490ff27 KH |
4288 | return 0; |
4289 | } | |
4290 | ||
c0ff4b85 | 4291 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) |
9490ff27 | 4292 | { |
7d74b06f KH |
4293 | struct mem_cgroup *iter; |
4294 | ||
c0ff4b85 | 4295 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 4296 | mem_cgroup_oom_notify_cb(iter); |
9490ff27 KH |
4297 | } |
4298 | ||
59b6f873 | 4299 | static int __mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 | 4300 | struct eventfd_ctx *eventfd, const char *args, enum res_type type) |
2e72b634 | 4301 | { |
2c488db2 KS |
4302 | struct mem_cgroup_thresholds *thresholds; |
4303 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e JW |
4304 | unsigned long threshold; |
4305 | unsigned long usage; | |
2c488db2 | 4306 | int i, size, ret; |
2e72b634 | 4307 | |
650c5e56 | 4308 | ret = page_counter_memparse(args, "-1", &threshold); |
2e72b634 KS |
4309 | if (ret) |
4310 | return ret; | |
4311 | ||
4312 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 4313 | |
05b84301 | 4314 | if (type == _MEM) { |
2c488db2 | 4315 | thresholds = &memcg->thresholds; |
ce00a967 | 4316 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 4317 | } else if (type == _MEMSWAP) { |
2c488db2 | 4318 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 4319 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 4320 | } else |
2e72b634 KS |
4321 | BUG(); |
4322 | ||
2e72b634 | 4323 | /* Check if a threshold crossed before adding a new one */ |
2c488db2 | 4324 | if (thresholds->primary) |
2e72b634 KS |
4325 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4326 | ||
2c488db2 | 4327 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
4328 | |
4329 | /* Allocate memory for new array of thresholds */ | |
67b8046f | 4330 | new = kmalloc(struct_size(new, entries, size), GFP_KERNEL); |
2c488db2 | 4331 | if (!new) { |
2e72b634 KS |
4332 | ret = -ENOMEM; |
4333 | goto unlock; | |
4334 | } | |
2c488db2 | 4335 | new->size = size; |
2e72b634 KS |
4336 | |
4337 | /* Copy thresholds (if any) to new array */ | |
e90342e6 GS |
4338 | if (thresholds->primary) |
4339 | memcpy(new->entries, thresholds->primary->entries, | |
4340 | flex_array_size(new, entries, size - 1)); | |
2c488db2 | 4341 | |
2e72b634 | 4342 | /* Add new threshold */ |
2c488db2 KS |
4343 | new->entries[size - 1].eventfd = eventfd; |
4344 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
4345 | |
4346 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
61e604e6 | 4347 | sort(new->entries, size, sizeof(*new->entries), |
2e72b634 KS |
4348 | compare_thresholds, NULL); |
4349 | ||
4350 | /* Find current threshold */ | |
2c488db2 | 4351 | new->current_threshold = -1; |
2e72b634 | 4352 | for (i = 0; i < size; i++) { |
748dad36 | 4353 | if (new->entries[i].threshold <= usage) { |
2e72b634 | 4354 | /* |
2c488db2 KS |
4355 | * new->current_threshold will not be used until |
4356 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
4357 | * it here. |
4358 | */ | |
2c488db2 | 4359 | ++new->current_threshold; |
748dad36 SZ |
4360 | } else |
4361 | break; | |
2e72b634 KS |
4362 | } |
4363 | ||
2c488db2 KS |
4364 | /* Free old spare buffer and save old primary buffer as spare */ |
4365 | kfree(thresholds->spare); | |
4366 | thresholds->spare = thresholds->primary; | |
4367 | ||
4368 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4369 | |
907860ed | 4370 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4371 | synchronize_rcu(); |
4372 | ||
2e72b634 KS |
4373 | unlock: |
4374 | mutex_unlock(&memcg->thresholds_lock); | |
4375 | ||
4376 | return ret; | |
4377 | } | |
4378 | ||
59b6f873 | 4379 | static int mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4380 | struct eventfd_ctx *eventfd, const char *args) |
4381 | { | |
59b6f873 | 4382 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEM); |
347c4a87 TH |
4383 | } |
4384 | ||
59b6f873 | 4385 | static int memsw_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4386 | struct eventfd_ctx *eventfd, const char *args) |
4387 | { | |
59b6f873 | 4388 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEMSWAP); |
347c4a87 TH |
4389 | } |
4390 | ||
59b6f873 | 4391 | static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 4392 | struct eventfd_ctx *eventfd, enum res_type type) |
2e72b634 | 4393 | { |
2c488db2 KS |
4394 | struct mem_cgroup_thresholds *thresholds; |
4395 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e | 4396 | unsigned long usage; |
7d36665a | 4397 | int i, j, size, entries; |
2e72b634 KS |
4398 | |
4399 | mutex_lock(&memcg->thresholds_lock); | |
05b84301 JW |
4400 | |
4401 | if (type == _MEM) { | |
2c488db2 | 4402 | thresholds = &memcg->thresholds; |
ce00a967 | 4403 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 4404 | } else if (type == _MEMSWAP) { |
2c488db2 | 4405 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 4406 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 4407 | } else |
2e72b634 KS |
4408 | BUG(); |
4409 | ||
371528ca AV |
4410 | if (!thresholds->primary) |
4411 | goto unlock; | |
4412 | ||
2e72b634 KS |
4413 | /* Check if a threshold crossed before removing */ |
4414 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
4415 | ||
4416 | /* Calculate new number of threshold */ | |
7d36665a | 4417 | size = entries = 0; |
2c488db2 KS |
4418 | for (i = 0; i < thresholds->primary->size; i++) { |
4419 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 | 4420 | size++; |
7d36665a CX |
4421 | else |
4422 | entries++; | |
2e72b634 KS |
4423 | } |
4424 | ||
2c488db2 | 4425 | new = thresholds->spare; |
907860ed | 4426 | |
7d36665a CX |
4427 | /* If no items related to eventfd have been cleared, nothing to do */ |
4428 | if (!entries) | |
4429 | goto unlock; | |
4430 | ||
2e72b634 KS |
4431 | /* Set thresholds array to NULL if we don't have thresholds */ |
4432 | if (!size) { | |
2c488db2 KS |
4433 | kfree(new); |
4434 | new = NULL; | |
907860ed | 4435 | goto swap_buffers; |
2e72b634 KS |
4436 | } |
4437 | ||
2c488db2 | 4438 | new->size = size; |
2e72b634 KS |
4439 | |
4440 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
4441 | new->current_threshold = -1; |
4442 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
4443 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
4444 | continue; |
4445 | ||
2c488db2 | 4446 | new->entries[j] = thresholds->primary->entries[i]; |
748dad36 | 4447 | if (new->entries[j].threshold <= usage) { |
2e72b634 | 4448 | /* |
2c488db2 | 4449 | * new->current_threshold will not be used |
2e72b634 KS |
4450 | * until rcu_assign_pointer(), so it's safe to increment |
4451 | * it here. | |
4452 | */ | |
2c488db2 | 4453 | ++new->current_threshold; |
2e72b634 KS |
4454 | } |
4455 | j++; | |
4456 | } | |
4457 | ||
907860ed | 4458 | swap_buffers: |
2c488db2 KS |
4459 | /* Swap primary and spare array */ |
4460 | thresholds->spare = thresholds->primary; | |
8c757763 | 4461 | |
2c488db2 | 4462 | rcu_assign_pointer(thresholds->primary, new); |
2e72b634 | 4463 | |
907860ed | 4464 | /* To be sure that nobody uses thresholds */ |
2e72b634 | 4465 | synchronize_rcu(); |
6611d8d7 MC |
4466 | |
4467 | /* If all events are unregistered, free the spare array */ | |
4468 | if (!new) { | |
4469 | kfree(thresholds->spare); | |
4470 | thresholds->spare = NULL; | |
4471 | } | |
371528ca | 4472 | unlock: |
2e72b634 | 4473 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 4474 | } |
c1e862c1 | 4475 | |
59b6f873 | 4476 | static void mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4477 | struct eventfd_ctx *eventfd) |
4478 | { | |
59b6f873 | 4479 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEM); |
347c4a87 TH |
4480 | } |
4481 | ||
59b6f873 | 4482 | static void memsw_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4483 | struct eventfd_ctx *eventfd) |
4484 | { | |
59b6f873 | 4485 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEMSWAP); |
347c4a87 TH |
4486 | } |
4487 | ||
59b6f873 | 4488 | static int mem_cgroup_oom_register_event(struct mem_cgroup *memcg, |
347c4a87 | 4489 | struct eventfd_ctx *eventfd, const char *args) |
9490ff27 | 4490 | { |
9490ff27 | 4491 | struct mem_cgroup_eventfd_list *event; |
9490ff27 | 4492 | |
9490ff27 KH |
4493 | event = kmalloc(sizeof(*event), GFP_KERNEL); |
4494 | if (!event) | |
4495 | return -ENOMEM; | |
4496 | ||
1af8efe9 | 4497 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4498 | |
4499 | event->eventfd = eventfd; | |
4500 | list_add(&event->list, &memcg->oom_notify); | |
4501 | ||
4502 | /* already in OOM ? */ | |
c2b42d3c | 4503 | if (memcg->under_oom) |
9490ff27 | 4504 | eventfd_signal(eventfd, 1); |
1af8efe9 | 4505 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4506 | |
4507 | return 0; | |
4508 | } | |
4509 | ||
59b6f873 | 4510 | static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 4511 | struct eventfd_ctx *eventfd) |
9490ff27 | 4512 | { |
9490ff27 | 4513 | struct mem_cgroup_eventfd_list *ev, *tmp; |
9490ff27 | 4514 | |
1af8efe9 | 4515 | spin_lock(&memcg_oom_lock); |
9490ff27 | 4516 | |
c0ff4b85 | 4517 | list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) { |
9490ff27 KH |
4518 | if (ev->eventfd == eventfd) { |
4519 | list_del(&ev->list); | |
4520 | kfree(ev); | |
4521 | } | |
4522 | } | |
4523 | ||
1af8efe9 | 4524 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4525 | } |
4526 | ||
2da8ca82 | 4527 | static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v) |
3c11ecf4 | 4528 | { |
aa9694bb | 4529 | struct mem_cgroup *memcg = mem_cgroup_from_seq(sf); |
3c11ecf4 | 4530 | |
17c56de6 | 4531 | seq_printf(sf, "oom_kill_disable %d\n", READ_ONCE(memcg->oom_kill_disable)); |
c2b42d3c | 4532 | seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom); |
fe6bdfc8 RG |
4533 | seq_printf(sf, "oom_kill %lu\n", |
4534 | atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL])); | |
3c11ecf4 KH |
4535 | return 0; |
4536 | } | |
4537 | ||
182446d0 | 4538 | static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css, |
3c11ecf4 KH |
4539 | struct cftype *cft, u64 val) |
4540 | { | |
182446d0 | 4541 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3c11ecf4 KH |
4542 | |
4543 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
a4792030 | 4544 | if (mem_cgroup_is_root(memcg) || !((val == 0) || (val == 1))) |
3c11ecf4 KH |
4545 | return -EINVAL; |
4546 | ||
17c56de6 | 4547 | WRITE_ONCE(memcg->oom_kill_disable, val); |
4d845ebf | 4548 | if (!val) |
c0ff4b85 | 4549 | memcg_oom_recover(memcg); |
3dae7fec | 4550 | |
3c11ecf4 KH |
4551 | return 0; |
4552 | } | |
4553 | ||
52ebea74 TH |
4554 | #ifdef CONFIG_CGROUP_WRITEBACK |
4555 | ||
3a8e9ac8 TH |
4556 | #include <trace/events/writeback.h> |
4557 | ||
841710aa TH |
4558 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) |
4559 | { | |
4560 | return wb_domain_init(&memcg->cgwb_domain, gfp); | |
4561 | } | |
4562 | ||
4563 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
4564 | { | |
4565 | wb_domain_exit(&memcg->cgwb_domain); | |
4566 | } | |
4567 | ||
2529bb3a TH |
4568 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
4569 | { | |
4570 | wb_domain_size_changed(&memcg->cgwb_domain); | |
4571 | } | |
4572 | ||
841710aa TH |
4573 | struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb) |
4574 | { | |
4575 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4576 | ||
4577 | if (!memcg->css.parent) | |
4578 | return NULL; | |
4579 | ||
4580 | return &memcg->cgwb_domain; | |
4581 | } | |
4582 | ||
c2aa723a TH |
4583 | /** |
4584 | * mem_cgroup_wb_stats - retrieve writeback related stats from its memcg | |
4585 | * @wb: bdi_writeback in question | |
c5edf9cd TH |
4586 | * @pfilepages: out parameter for number of file pages |
4587 | * @pheadroom: out parameter for number of allocatable pages according to memcg | |
c2aa723a TH |
4588 | * @pdirty: out parameter for number of dirty pages |
4589 | * @pwriteback: out parameter for number of pages under writeback | |
4590 | * | |
c5edf9cd TH |
4591 | * Determine the numbers of file, headroom, dirty, and writeback pages in |
4592 | * @wb's memcg. File, dirty and writeback are self-explanatory. Headroom | |
4593 | * is a bit more involved. | |
c2aa723a | 4594 | * |
c5edf9cd TH |
4595 | * A memcg's headroom is "min(max, high) - used". In the hierarchy, the |
4596 | * headroom is calculated as the lowest headroom of itself and the | |
4597 | * ancestors. Note that this doesn't consider the actual amount of | |
4598 | * available memory in the system. The caller should further cap | |
4599 | * *@pheadroom accordingly. | |
c2aa723a | 4600 | */ |
c5edf9cd TH |
4601 | void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, |
4602 | unsigned long *pheadroom, unsigned long *pdirty, | |
4603 | unsigned long *pwriteback) | |
c2aa723a TH |
4604 | { |
4605 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4606 | struct mem_cgroup *parent; | |
c2aa723a | 4607 | |
190409ca | 4608 | mem_cgroup_flush_stats(); |
c2aa723a | 4609 | |
2d146aa3 JW |
4610 | *pdirty = memcg_page_state(memcg, NR_FILE_DIRTY); |
4611 | *pwriteback = memcg_page_state(memcg, NR_WRITEBACK); | |
4612 | *pfilepages = memcg_page_state(memcg, NR_INACTIVE_FILE) + | |
4613 | memcg_page_state(memcg, NR_ACTIVE_FILE); | |
c2aa723a | 4614 | |
2d146aa3 | 4615 | *pheadroom = PAGE_COUNTER_MAX; |
c2aa723a | 4616 | while ((parent = parent_mem_cgroup(memcg))) { |
15b42562 | 4617 | unsigned long ceiling = min(READ_ONCE(memcg->memory.max), |
d1663a90 | 4618 | READ_ONCE(memcg->memory.high)); |
c2aa723a TH |
4619 | unsigned long used = page_counter_read(&memcg->memory); |
4620 | ||
c5edf9cd | 4621 | *pheadroom = min(*pheadroom, ceiling - min(ceiling, used)); |
c2aa723a TH |
4622 | memcg = parent; |
4623 | } | |
c2aa723a TH |
4624 | } |
4625 | ||
97b27821 TH |
4626 | /* |
4627 | * Foreign dirty flushing | |
4628 | * | |
4629 | * There's an inherent mismatch between memcg and writeback. The former | |
f0953a1b | 4630 | * tracks ownership per-page while the latter per-inode. This was a |
97b27821 TH |
4631 | * deliberate design decision because honoring per-page ownership in the |
4632 | * writeback path is complicated, may lead to higher CPU and IO overheads | |
4633 | * and deemed unnecessary given that write-sharing an inode across | |
4634 | * different cgroups isn't a common use-case. | |
4635 | * | |
4636 | * Combined with inode majority-writer ownership switching, this works well | |
4637 | * enough in most cases but there are some pathological cases. For | |
4638 | * example, let's say there are two cgroups A and B which keep writing to | |
4639 | * different but confined parts of the same inode. B owns the inode and | |
4640 | * A's memory is limited far below B's. A's dirty ratio can rise enough to | |
4641 | * trigger balance_dirty_pages() sleeps but B's can be low enough to avoid | |
4642 | * triggering background writeback. A will be slowed down without a way to | |
4643 | * make writeback of the dirty pages happen. | |
4644 | * | |
f0953a1b | 4645 | * Conditions like the above can lead to a cgroup getting repeatedly and |
97b27821 | 4646 | * severely throttled after making some progress after each |
f0953a1b | 4647 | * dirty_expire_interval while the underlying IO device is almost |
97b27821 TH |
4648 | * completely idle. |
4649 | * | |
4650 | * Solving this problem completely requires matching the ownership tracking | |
4651 | * granularities between memcg and writeback in either direction. However, | |
4652 | * the more egregious behaviors can be avoided by simply remembering the | |
4653 | * most recent foreign dirtying events and initiating remote flushes on | |
4654 | * them when local writeback isn't enough to keep the memory clean enough. | |
4655 | * | |
4656 | * The following two functions implement such mechanism. When a foreign | |
4657 | * page - a page whose memcg and writeback ownerships don't match - is | |
4658 | * dirtied, mem_cgroup_track_foreign_dirty() records the inode owning | |
4659 | * bdi_writeback on the page owning memcg. When balance_dirty_pages() | |
4660 | * decides that the memcg needs to sleep due to high dirty ratio, it calls | |
4661 | * mem_cgroup_flush_foreign() which queues writeback on the recorded | |
4662 | * foreign bdi_writebacks which haven't expired. Both the numbers of | |
4663 | * recorded bdi_writebacks and concurrent in-flight foreign writebacks are | |
4664 | * limited to MEMCG_CGWB_FRN_CNT. | |
4665 | * | |
4666 | * The mechanism only remembers IDs and doesn't hold any object references. | |
4667 | * As being wrong occasionally doesn't matter, updates and accesses to the | |
4668 | * records are lockless and racy. | |
4669 | */ | |
9d8053fc | 4670 | void mem_cgroup_track_foreign_dirty_slowpath(struct folio *folio, |
97b27821 TH |
4671 | struct bdi_writeback *wb) |
4672 | { | |
9d8053fc | 4673 | struct mem_cgroup *memcg = folio_memcg(folio); |
97b27821 TH |
4674 | struct memcg_cgwb_frn *frn; |
4675 | u64 now = get_jiffies_64(); | |
4676 | u64 oldest_at = now; | |
4677 | int oldest = -1; | |
4678 | int i; | |
4679 | ||
9d8053fc | 4680 | trace_track_foreign_dirty(folio, wb); |
3a8e9ac8 | 4681 | |
97b27821 TH |
4682 | /* |
4683 | * Pick the slot to use. If there is already a slot for @wb, keep | |
4684 | * using it. If not replace the oldest one which isn't being | |
4685 | * written out. | |
4686 | */ | |
4687 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) { | |
4688 | frn = &memcg->cgwb_frn[i]; | |
4689 | if (frn->bdi_id == wb->bdi->id && | |
4690 | frn->memcg_id == wb->memcg_css->id) | |
4691 | break; | |
4692 | if (time_before64(frn->at, oldest_at) && | |
4693 | atomic_read(&frn->done.cnt) == 1) { | |
4694 | oldest = i; | |
4695 | oldest_at = frn->at; | |
4696 | } | |
4697 | } | |
4698 | ||
4699 | if (i < MEMCG_CGWB_FRN_CNT) { | |
4700 | /* | |
4701 | * Re-using an existing one. Update timestamp lazily to | |
4702 | * avoid making the cacheline hot. We want them to be | |
4703 | * reasonably up-to-date and significantly shorter than | |
4704 | * dirty_expire_interval as that's what expires the record. | |
4705 | * Use the shorter of 1s and dirty_expire_interval / 8. | |
4706 | */ | |
4707 | unsigned long update_intv = | |
4708 | min_t(unsigned long, HZ, | |
4709 | msecs_to_jiffies(dirty_expire_interval * 10) / 8); | |
4710 | ||
4711 | if (time_before64(frn->at, now - update_intv)) | |
4712 | frn->at = now; | |
4713 | } else if (oldest >= 0) { | |
4714 | /* replace the oldest free one */ | |
4715 | frn = &memcg->cgwb_frn[oldest]; | |
4716 | frn->bdi_id = wb->bdi->id; | |
4717 | frn->memcg_id = wb->memcg_css->id; | |
4718 | frn->at = now; | |
4719 | } | |
4720 | } | |
4721 | ||
4722 | /* issue foreign writeback flushes for recorded foreign dirtying events */ | |
4723 | void mem_cgroup_flush_foreign(struct bdi_writeback *wb) | |
4724 | { | |
4725 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4726 | unsigned long intv = msecs_to_jiffies(dirty_expire_interval * 10); | |
4727 | u64 now = jiffies_64; | |
4728 | int i; | |
4729 | ||
4730 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) { | |
4731 | struct memcg_cgwb_frn *frn = &memcg->cgwb_frn[i]; | |
4732 | ||
4733 | /* | |
4734 | * If the record is older than dirty_expire_interval, | |
4735 | * writeback on it has already started. No need to kick it | |
4736 | * off again. Also, don't start a new one if there's | |
4737 | * already one in flight. | |
4738 | */ | |
4739 | if (time_after64(frn->at, now - intv) && | |
4740 | atomic_read(&frn->done.cnt) == 1) { | |
4741 | frn->at = 0; | |
3a8e9ac8 | 4742 | trace_flush_foreign(wb, frn->bdi_id, frn->memcg_id); |
7490a2d2 | 4743 | cgroup_writeback_by_id(frn->bdi_id, frn->memcg_id, |
97b27821 TH |
4744 | WB_REASON_FOREIGN_FLUSH, |
4745 | &frn->done); | |
4746 | } | |
4747 | } | |
4748 | } | |
4749 | ||
841710aa TH |
4750 | #else /* CONFIG_CGROUP_WRITEBACK */ |
4751 | ||
4752 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) | |
4753 | { | |
4754 | return 0; | |
4755 | } | |
4756 | ||
4757 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
4758 | { | |
4759 | } | |
4760 | ||
2529bb3a TH |
4761 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
4762 | { | |
4763 | } | |
4764 | ||
52ebea74 TH |
4765 | #endif /* CONFIG_CGROUP_WRITEBACK */ |
4766 | ||
3bc942f3 TH |
4767 | /* |
4768 | * DO NOT USE IN NEW FILES. | |
4769 | * | |
4770 | * "cgroup.event_control" implementation. | |
4771 | * | |
4772 | * This is way over-engineered. It tries to support fully configurable | |
4773 | * events for each user. Such level of flexibility is completely | |
4774 | * unnecessary especially in the light of the planned unified hierarchy. | |
4775 | * | |
4776 | * Please deprecate this and replace with something simpler if at all | |
4777 | * possible. | |
4778 | */ | |
4779 | ||
79bd9814 TH |
4780 | /* |
4781 | * Unregister event and free resources. | |
4782 | * | |
4783 | * Gets called from workqueue. | |
4784 | */ | |
3bc942f3 | 4785 | static void memcg_event_remove(struct work_struct *work) |
79bd9814 | 4786 | { |
3bc942f3 TH |
4787 | struct mem_cgroup_event *event = |
4788 | container_of(work, struct mem_cgroup_event, remove); | |
59b6f873 | 4789 | struct mem_cgroup *memcg = event->memcg; |
79bd9814 TH |
4790 | |
4791 | remove_wait_queue(event->wqh, &event->wait); | |
4792 | ||
59b6f873 | 4793 | event->unregister_event(memcg, event->eventfd); |
79bd9814 TH |
4794 | |
4795 | /* Notify userspace the event is going away. */ | |
4796 | eventfd_signal(event->eventfd, 1); | |
4797 | ||
4798 | eventfd_ctx_put(event->eventfd); | |
4799 | kfree(event); | |
59b6f873 | 4800 | css_put(&memcg->css); |
79bd9814 TH |
4801 | } |
4802 | ||
4803 | /* | |
a9a08845 | 4804 | * Gets called on EPOLLHUP on eventfd when user closes it. |
79bd9814 TH |
4805 | * |
4806 | * Called with wqh->lock held and interrupts disabled. | |
4807 | */ | |
ac6424b9 | 4808 | static int memcg_event_wake(wait_queue_entry_t *wait, unsigned mode, |
3bc942f3 | 4809 | int sync, void *key) |
79bd9814 | 4810 | { |
3bc942f3 TH |
4811 | struct mem_cgroup_event *event = |
4812 | container_of(wait, struct mem_cgroup_event, wait); | |
59b6f873 | 4813 | struct mem_cgroup *memcg = event->memcg; |
3ad6f93e | 4814 | __poll_t flags = key_to_poll(key); |
79bd9814 | 4815 | |
a9a08845 | 4816 | if (flags & EPOLLHUP) { |
79bd9814 TH |
4817 | /* |
4818 | * If the event has been detached at cgroup removal, we | |
4819 | * can simply return knowing the other side will cleanup | |
4820 | * for us. | |
4821 | * | |
4822 | * We can't race against event freeing since the other | |
4823 | * side will require wqh->lock via remove_wait_queue(), | |
4824 | * which we hold. | |
4825 | */ | |
fba94807 | 4826 | spin_lock(&memcg->event_list_lock); |
79bd9814 TH |
4827 | if (!list_empty(&event->list)) { |
4828 | list_del_init(&event->list); | |
4829 | /* | |
4830 | * We are in atomic context, but cgroup_event_remove() | |
4831 | * may sleep, so we have to call it in workqueue. | |
4832 | */ | |
4833 | schedule_work(&event->remove); | |
4834 | } | |
fba94807 | 4835 | spin_unlock(&memcg->event_list_lock); |
79bd9814 TH |
4836 | } |
4837 | ||
4838 | return 0; | |
4839 | } | |
4840 | ||
3bc942f3 | 4841 | static void memcg_event_ptable_queue_proc(struct file *file, |
79bd9814 TH |
4842 | wait_queue_head_t *wqh, poll_table *pt) |
4843 | { | |
3bc942f3 TH |
4844 | struct mem_cgroup_event *event = |
4845 | container_of(pt, struct mem_cgroup_event, pt); | |
79bd9814 TH |
4846 | |
4847 | event->wqh = wqh; | |
4848 | add_wait_queue(wqh, &event->wait); | |
4849 | } | |
4850 | ||
4851 | /* | |
3bc942f3 TH |
4852 | * DO NOT USE IN NEW FILES. |
4853 | * | |
79bd9814 TH |
4854 | * Parse input and register new cgroup event handler. |
4855 | * | |
4856 | * Input must be in format '<event_fd> <control_fd> <args>'. | |
4857 | * Interpretation of args is defined by control file implementation. | |
4858 | */ | |
451af504 TH |
4859 | static ssize_t memcg_write_event_control(struct kernfs_open_file *of, |
4860 | char *buf, size_t nbytes, loff_t off) | |
79bd9814 | 4861 | { |
451af504 | 4862 | struct cgroup_subsys_state *css = of_css(of); |
fba94807 | 4863 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 4864 | struct mem_cgroup_event *event; |
79bd9814 TH |
4865 | struct cgroup_subsys_state *cfile_css; |
4866 | unsigned int efd, cfd; | |
4867 | struct fd efile; | |
4868 | struct fd cfile; | |
4a7ba45b | 4869 | struct dentry *cdentry; |
fba94807 | 4870 | const char *name; |
79bd9814 TH |
4871 | char *endp; |
4872 | int ret; | |
4873 | ||
2343e88d SAS |
4874 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) |
4875 | return -EOPNOTSUPP; | |
4876 | ||
451af504 TH |
4877 | buf = strstrip(buf); |
4878 | ||
4879 | efd = simple_strtoul(buf, &endp, 10); | |
79bd9814 TH |
4880 | if (*endp != ' ') |
4881 | return -EINVAL; | |
451af504 | 4882 | buf = endp + 1; |
79bd9814 | 4883 | |
451af504 | 4884 | cfd = simple_strtoul(buf, &endp, 10); |
79bd9814 TH |
4885 | if ((*endp != ' ') && (*endp != '\0')) |
4886 | return -EINVAL; | |
451af504 | 4887 | buf = endp + 1; |
79bd9814 TH |
4888 | |
4889 | event = kzalloc(sizeof(*event), GFP_KERNEL); | |
4890 | if (!event) | |
4891 | return -ENOMEM; | |
4892 | ||
59b6f873 | 4893 | event->memcg = memcg; |
79bd9814 | 4894 | INIT_LIST_HEAD(&event->list); |
3bc942f3 TH |
4895 | init_poll_funcptr(&event->pt, memcg_event_ptable_queue_proc); |
4896 | init_waitqueue_func_entry(&event->wait, memcg_event_wake); | |
4897 | INIT_WORK(&event->remove, memcg_event_remove); | |
79bd9814 TH |
4898 | |
4899 | efile = fdget(efd); | |
4900 | if (!efile.file) { | |
4901 | ret = -EBADF; | |
4902 | goto out_kfree; | |
4903 | } | |
4904 | ||
4905 | event->eventfd = eventfd_ctx_fileget(efile.file); | |
4906 | if (IS_ERR(event->eventfd)) { | |
4907 | ret = PTR_ERR(event->eventfd); | |
4908 | goto out_put_efile; | |
4909 | } | |
4910 | ||
4911 | cfile = fdget(cfd); | |
4912 | if (!cfile.file) { | |
4913 | ret = -EBADF; | |
4914 | goto out_put_eventfd; | |
4915 | } | |
4916 | ||
4917 | /* the process need read permission on control file */ | |
4918 | /* AV: shouldn't we check that it's been opened for read instead? */ | |
02f92b38 | 4919 | ret = file_permission(cfile.file, MAY_READ); |
79bd9814 TH |
4920 | if (ret < 0) |
4921 | goto out_put_cfile; | |
4922 | ||
4a7ba45b TH |
4923 | /* |
4924 | * The control file must be a regular cgroup1 file. As a regular cgroup | |
4925 | * file can't be renamed, it's safe to access its name afterwards. | |
4926 | */ | |
4927 | cdentry = cfile.file->f_path.dentry; | |
4928 | if (cdentry->d_sb->s_type != &cgroup_fs_type || !d_is_reg(cdentry)) { | |
4929 | ret = -EINVAL; | |
4930 | goto out_put_cfile; | |
4931 | } | |
4932 | ||
fba94807 TH |
4933 | /* |
4934 | * Determine the event callbacks and set them in @event. This used | |
4935 | * to be done via struct cftype but cgroup core no longer knows | |
4936 | * about these events. The following is crude but the whole thing | |
4937 | * is for compatibility anyway. | |
3bc942f3 TH |
4938 | * |
4939 | * DO NOT ADD NEW FILES. | |
fba94807 | 4940 | */ |
4a7ba45b | 4941 | name = cdentry->d_name.name; |
fba94807 TH |
4942 | |
4943 | if (!strcmp(name, "memory.usage_in_bytes")) { | |
4944 | event->register_event = mem_cgroup_usage_register_event; | |
4945 | event->unregister_event = mem_cgroup_usage_unregister_event; | |
4946 | } else if (!strcmp(name, "memory.oom_control")) { | |
4947 | event->register_event = mem_cgroup_oom_register_event; | |
4948 | event->unregister_event = mem_cgroup_oom_unregister_event; | |
4949 | } else if (!strcmp(name, "memory.pressure_level")) { | |
4950 | event->register_event = vmpressure_register_event; | |
4951 | event->unregister_event = vmpressure_unregister_event; | |
4952 | } else if (!strcmp(name, "memory.memsw.usage_in_bytes")) { | |
347c4a87 TH |
4953 | event->register_event = memsw_cgroup_usage_register_event; |
4954 | event->unregister_event = memsw_cgroup_usage_unregister_event; | |
fba94807 TH |
4955 | } else { |
4956 | ret = -EINVAL; | |
4957 | goto out_put_cfile; | |
4958 | } | |
4959 | ||
79bd9814 | 4960 | /* |
b5557c4c TH |
4961 | * Verify @cfile should belong to @css. Also, remaining events are |
4962 | * automatically removed on cgroup destruction but the removal is | |
4963 | * asynchronous, so take an extra ref on @css. | |
79bd9814 | 4964 | */ |
4a7ba45b | 4965 | cfile_css = css_tryget_online_from_dir(cdentry->d_parent, |
ec903c0c | 4966 | &memory_cgrp_subsys); |
79bd9814 | 4967 | ret = -EINVAL; |
5a17f543 | 4968 | if (IS_ERR(cfile_css)) |
79bd9814 | 4969 | goto out_put_cfile; |
5a17f543 TH |
4970 | if (cfile_css != css) { |
4971 | css_put(cfile_css); | |
79bd9814 | 4972 | goto out_put_cfile; |
5a17f543 | 4973 | } |
79bd9814 | 4974 | |
451af504 | 4975 | ret = event->register_event(memcg, event->eventfd, buf); |
79bd9814 TH |
4976 | if (ret) |
4977 | goto out_put_css; | |
4978 | ||
9965ed17 | 4979 | vfs_poll(efile.file, &event->pt); |
79bd9814 | 4980 | |
4ba9515d | 4981 | spin_lock_irq(&memcg->event_list_lock); |
fba94807 | 4982 | list_add(&event->list, &memcg->event_list); |
4ba9515d | 4983 | spin_unlock_irq(&memcg->event_list_lock); |
79bd9814 TH |
4984 | |
4985 | fdput(cfile); | |
4986 | fdput(efile); | |
4987 | ||
451af504 | 4988 | return nbytes; |
79bd9814 TH |
4989 | |
4990 | out_put_css: | |
b5557c4c | 4991 | css_put(css); |
79bd9814 TH |
4992 | out_put_cfile: |
4993 | fdput(cfile); | |
4994 | out_put_eventfd: | |
4995 | eventfd_ctx_put(event->eventfd); | |
4996 | out_put_efile: | |
4997 | fdput(efile); | |
4998 | out_kfree: | |
4999 | kfree(event); | |
5000 | ||
5001 | return ret; | |
5002 | } | |
5003 | ||
c29b5b3d MS |
5004 | #if defined(CONFIG_MEMCG_KMEM) && (defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)) |
5005 | static int mem_cgroup_slab_show(struct seq_file *m, void *p) | |
5006 | { | |
5007 | /* | |
5008 | * Deprecated. | |
df4ae285 | 5009 | * Please, take a look at tools/cgroup/memcg_slabinfo.py . |
c29b5b3d MS |
5010 | */ |
5011 | return 0; | |
5012 | } | |
5013 | #endif | |
5014 | ||
dddb44ff YA |
5015 | static int memory_stat_show(struct seq_file *m, void *v); |
5016 | ||
241994ed | 5017 | static struct cftype mem_cgroup_legacy_files[] = { |
8cdea7c0 | 5018 | { |
0eea1030 | 5019 | .name = "usage_in_bytes", |
8c7c6e34 | 5020 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
791badbd | 5021 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 5022 | }, |
c84872e1 PE |
5023 | { |
5024 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 5025 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
6770c64e | 5026 | .write = mem_cgroup_reset, |
791badbd | 5027 | .read_u64 = mem_cgroup_read_u64, |
c84872e1 | 5028 | }, |
8cdea7c0 | 5029 | { |
0eea1030 | 5030 | .name = "limit_in_bytes", |
8c7c6e34 | 5031 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
451af504 | 5032 | .write = mem_cgroup_write, |
791badbd | 5033 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 5034 | }, |
296c81d8 BS |
5035 | { |
5036 | .name = "soft_limit_in_bytes", | |
5037 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
451af504 | 5038 | .write = mem_cgroup_write, |
791badbd | 5039 | .read_u64 = mem_cgroup_read_u64, |
296c81d8 | 5040 | }, |
8cdea7c0 BS |
5041 | { |
5042 | .name = "failcnt", | |
8c7c6e34 | 5043 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
6770c64e | 5044 | .write = mem_cgroup_reset, |
791badbd | 5045 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 5046 | }, |
d2ceb9b7 KH |
5047 | { |
5048 | .name = "stat", | |
dddb44ff | 5049 | .seq_show = memory_stat_show, |
d2ceb9b7 | 5050 | }, |
c1e862c1 KH |
5051 | { |
5052 | .name = "force_empty", | |
6770c64e | 5053 | .write = mem_cgroup_force_empty_write, |
c1e862c1 | 5054 | }, |
18f59ea7 BS |
5055 | { |
5056 | .name = "use_hierarchy", | |
5057 | .write_u64 = mem_cgroup_hierarchy_write, | |
5058 | .read_u64 = mem_cgroup_hierarchy_read, | |
5059 | }, | |
79bd9814 | 5060 | { |
3bc942f3 | 5061 | .name = "cgroup.event_control", /* XXX: for compat */ |
451af504 | 5062 | .write = memcg_write_event_control, |
7dbdb199 | 5063 | .flags = CFTYPE_NO_PREFIX | CFTYPE_WORLD_WRITABLE, |
79bd9814 | 5064 | }, |
a7885eb8 KM |
5065 | { |
5066 | .name = "swappiness", | |
5067 | .read_u64 = mem_cgroup_swappiness_read, | |
5068 | .write_u64 = mem_cgroup_swappiness_write, | |
5069 | }, | |
7dc74be0 DN |
5070 | { |
5071 | .name = "move_charge_at_immigrate", | |
5072 | .read_u64 = mem_cgroup_move_charge_read, | |
5073 | .write_u64 = mem_cgroup_move_charge_write, | |
5074 | }, | |
9490ff27 KH |
5075 | { |
5076 | .name = "oom_control", | |
2da8ca82 | 5077 | .seq_show = mem_cgroup_oom_control_read, |
3c11ecf4 | 5078 | .write_u64 = mem_cgroup_oom_control_write, |
9490ff27 | 5079 | }, |
70ddf637 AV |
5080 | { |
5081 | .name = "pressure_level", | |
6b0ba2ab | 5082 | .seq_show = mem_cgroup_dummy_seq_show, |
70ddf637 | 5083 | }, |
406eb0c9 YH |
5084 | #ifdef CONFIG_NUMA |
5085 | { | |
5086 | .name = "numa_stat", | |
2da8ca82 | 5087 | .seq_show = memcg_numa_stat_show, |
406eb0c9 YH |
5088 | }, |
5089 | #endif | |
4597648f MH |
5090 | { |
5091 | .name = "kmem.limit_in_bytes", | |
5092 | .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT), | |
5093 | .write = mem_cgroup_write, | |
5094 | .read_u64 = mem_cgroup_read_u64, | |
5095 | }, | |
510fc4e1 GC |
5096 | { |
5097 | .name = "kmem.usage_in_bytes", | |
5098 | .private = MEMFILE_PRIVATE(_KMEM, RES_USAGE), | |
791badbd | 5099 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
5100 | }, |
5101 | { | |
5102 | .name = "kmem.failcnt", | |
5103 | .private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT), | |
6770c64e | 5104 | .write = mem_cgroup_reset, |
791badbd | 5105 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
5106 | }, |
5107 | { | |
5108 | .name = "kmem.max_usage_in_bytes", | |
5109 | .private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE), | |
6770c64e | 5110 | .write = mem_cgroup_reset, |
791badbd | 5111 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 | 5112 | }, |
a87425a3 YS |
5113 | #if defined(CONFIG_MEMCG_KMEM) && \ |
5114 | (defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)) | |
749c5415 GC |
5115 | { |
5116 | .name = "kmem.slabinfo", | |
c29b5b3d | 5117 | .seq_show = mem_cgroup_slab_show, |
749c5415 GC |
5118 | }, |
5119 | #endif | |
d55f90bf VD |
5120 | { |
5121 | .name = "kmem.tcp.limit_in_bytes", | |
5122 | .private = MEMFILE_PRIVATE(_TCP, RES_LIMIT), | |
5123 | .write = mem_cgroup_write, | |
5124 | .read_u64 = mem_cgroup_read_u64, | |
5125 | }, | |
5126 | { | |
5127 | .name = "kmem.tcp.usage_in_bytes", | |
5128 | .private = MEMFILE_PRIVATE(_TCP, RES_USAGE), | |
5129 | .read_u64 = mem_cgroup_read_u64, | |
5130 | }, | |
5131 | { | |
5132 | .name = "kmem.tcp.failcnt", | |
5133 | .private = MEMFILE_PRIVATE(_TCP, RES_FAILCNT), | |
5134 | .write = mem_cgroup_reset, | |
5135 | .read_u64 = mem_cgroup_read_u64, | |
5136 | }, | |
5137 | { | |
5138 | .name = "kmem.tcp.max_usage_in_bytes", | |
5139 | .private = MEMFILE_PRIVATE(_TCP, RES_MAX_USAGE), | |
5140 | .write = mem_cgroup_reset, | |
5141 | .read_u64 = mem_cgroup_read_u64, | |
5142 | }, | |
6bc10349 | 5143 | { }, /* terminate */ |
af36f906 | 5144 | }; |
8c7c6e34 | 5145 | |
73f576c0 JW |
5146 | /* |
5147 | * Private memory cgroup IDR | |
5148 | * | |
5149 | * Swap-out records and page cache shadow entries need to store memcg | |
5150 | * references in constrained space, so we maintain an ID space that is | |
5151 | * limited to 16 bit (MEM_CGROUP_ID_MAX), limiting the total number of | |
5152 | * memory-controlled cgroups to 64k. | |
5153 | * | |
b8f2935f | 5154 | * However, there usually are many references to the offline CSS after |
73f576c0 JW |
5155 | * the cgroup has been destroyed, such as page cache or reclaimable |
5156 | * slab objects, that don't need to hang on to the ID. We want to keep | |
5157 | * those dead CSS from occupying IDs, or we might quickly exhaust the | |
5158 | * relatively small ID space and prevent the creation of new cgroups | |
5159 | * even when there are much fewer than 64k cgroups - possibly none. | |
5160 | * | |
5161 | * Maintain a private 16-bit ID space for memcg, and allow the ID to | |
5162 | * be freed and recycled when it's no longer needed, which is usually | |
5163 | * when the CSS is offlined. | |
5164 | * | |
5165 | * The only exception to that are records of swapped out tmpfs/shmem | |
5166 | * pages that need to be attributed to live ancestors on swapin. But | |
5167 | * those references are manageable from userspace. | |
5168 | */ | |
5169 | ||
60b1e24c | 5170 | #define MEM_CGROUP_ID_MAX ((1UL << MEM_CGROUP_ID_SHIFT) - 1) |
73f576c0 JW |
5171 | static DEFINE_IDR(mem_cgroup_idr); |
5172 | ||
7e97de0b KT |
5173 | static void mem_cgroup_id_remove(struct mem_cgroup *memcg) |
5174 | { | |
5175 | if (memcg->id.id > 0) { | |
5176 | idr_remove(&mem_cgroup_idr, memcg->id.id); | |
5177 | memcg->id.id = 0; | |
5178 | } | |
5179 | } | |
5180 | ||
c1514c0a VF |
5181 | static void __maybe_unused mem_cgroup_id_get_many(struct mem_cgroup *memcg, |
5182 | unsigned int n) | |
73f576c0 | 5183 | { |
1c2d479a | 5184 | refcount_add(n, &memcg->id.ref); |
73f576c0 JW |
5185 | } |
5186 | ||
615d66c3 | 5187 | static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n) |
73f576c0 | 5188 | { |
1c2d479a | 5189 | if (refcount_sub_and_test(n, &memcg->id.ref)) { |
7e97de0b | 5190 | mem_cgroup_id_remove(memcg); |
73f576c0 JW |
5191 | |
5192 | /* Memcg ID pins CSS */ | |
5193 | css_put(&memcg->css); | |
5194 | } | |
5195 | } | |
5196 | ||
615d66c3 VD |
5197 | static inline void mem_cgroup_id_put(struct mem_cgroup *memcg) |
5198 | { | |
5199 | mem_cgroup_id_put_many(memcg, 1); | |
5200 | } | |
5201 | ||
73f576c0 JW |
5202 | /** |
5203 | * mem_cgroup_from_id - look up a memcg from a memcg id | |
5204 | * @id: the memcg id to look up | |
5205 | * | |
5206 | * Caller must hold rcu_read_lock(). | |
5207 | */ | |
5208 | struct mem_cgroup *mem_cgroup_from_id(unsigned short id) | |
5209 | { | |
5210 | WARN_ON_ONCE(!rcu_read_lock_held()); | |
5211 | return idr_find(&mem_cgroup_idr, id); | |
5212 | } | |
5213 | ||
c15187a4 RG |
5214 | #ifdef CONFIG_SHRINKER_DEBUG |
5215 | struct mem_cgroup *mem_cgroup_get_from_ino(unsigned long ino) | |
5216 | { | |
5217 | struct cgroup *cgrp; | |
5218 | struct cgroup_subsys_state *css; | |
5219 | struct mem_cgroup *memcg; | |
5220 | ||
5221 | cgrp = cgroup_get_from_id(ino); | |
fa7e439c | 5222 | if (IS_ERR(cgrp)) |
c0f2df49 | 5223 | return ERR_CAST(cgrp); |
c15187a4 RG |
5224 | |
5225 | css = cgroup_get_e_css(cgrp, &memory_cgrp_subsys); | |
5226 | if (css) | |
5227 | memcg = container_of(css, struct mem_cgroup, css); | |
5228 | else | |
5229 | memcg = ERR_PTR(-ENOENT); | |
5230 | ||
5231 | cgroup_put(cgrp); | |
5232 | ||
5233 | return memcg; | |
5234 | } | |
5235 | #endif | |
5236 | ||
ef8f2327 | 5237 | static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) |
6d12e2d8 KH |
5238 | { |
5239 | struct mem_cgroup_per_node *pn; | |
8c9bb398 WY |
5240 | |
5241 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, node); | |
6d12e2d8 KH |
5242 | if (!pn) |
5243 | return 1; | |
1ecaab2b | 5244 | |
7e1c0d6f SB |
5245 | pn->lruvec_stats_percpu = alloc_percpu_gfp(struct lruvec_stats_percpu, |
5246 | GFP_KERNEL_ACCOUNT); | |
5247 | if (!pn->lruvec_stats_percpu) { | |
00f3ca2c JW |
5248 | kfree(pn); |
5249 | return 1; | |
5250 | } | |
5251 | ||
ef8f2327 | 5252 | lruvec_init(&pn->lruvec); |
ef8f2327 MG |
5253 | pn->memcg = memcg; |
5254 | ||
54f72fe0 | 5255 | memcg->nodeinfo[node] = pn; |
6d12e2d8 KH |
5256 | return 0; |
5257 | } | |
5258 | ||
ef8f2327 | 5259 | static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) |
1ecaab2b | 5260 | { |
00f3ca2c JW |
5261 | struct mem_cgroup_per_node *pn = memcg->nodeinfo[node]; |
5262 | ||
4eaf431f MH |
5263 | if (!pn) |
5264 | return; | |
5265 | ||
7e1c0d6f | 5266 | free_percpu(pn->lruvec_stats_percpu); |
00f3ca2c | 5267 | kfree(pn); |
1ecaab2b KH |
5268 | } |
5269 | ||
40e952f9 | 5270 | static void __mem_cgroup_free(struct mem_cgroup *memcg) |
59927fb9 | 5271 | { |
c8b2a36f | 5272 | int node; |
59927fb9 | 5273 | |
c8b2a36f | 5274 | for_each_node(node) |
ef8f2327 | 5275 | free_mem_cgroup_per_node_info(memcg, node); |
410f8e82 | 5276 | kfree(memcg->vmstats); |
871789d4 | 5277 | free_percpu(memcg->vmstats_percpu); |
8ff69e2c | 5278 | kfree(memcg); |
59927fb9 | 5279 | } |
3afe36b1 | 5280 | |
40e952f9 TE |
5281 | static void mem_cgroup_free(struct mem_cgroup *memcg) |
5282 | { | |
ec1c86b2 | 5283 | lru_gen_exit_memcg(memcg); |
40e952f9 TE |
5284 | memcg_wb_domain_exit(memcg); |
5285 | __mem_cgroup_free(memcg); | |
5286 | } | |
5287 | ||
0b8f73e1 | 5288 | static struct mem_cgroup *mem_cgroup_alloc(void) |
8cdea7c0 | 5289 | { |
d142e3e6 | 5290 | struct mem_cgroup *memcg; |
6d12e2d8 | 5291 | int node; |
97b27821 | 5292 | int __maybe_unused i; |
11d67612 | 5293 | long error = -ENOMEM; |
8cdea7c0 | 5294 | |
06b2c3b0 | 5295 | memcg = kzalloc(struct_size(memcg, nodeinfo, nr_node_ids), GFP_KERNEL); |
c0ff4b85 | 5296 | if (!memcg) |
11d67612 | 5297 | return ERR_PTR(error); |
0b8f73e1 | 5298 | |
73f576c0 | 5299 | memcg->id.id = idr_alloc(&mem_cgroup_idr, NULL, |
be740503 | 5300 | 1, MEM_CGROUP_ID_MAX + 1, GFP_KERNEL); |
11d67612 YS |
5301 | if (memcg->id.id < 0) { |
5302 | error = memcg->id.id; | |
73f576c0 | 5303 | goto fail; |
11d67612 | 5304 | } |
73f576c0 | 5305 | |
410f8e82 SB |
5306 | memcg->vmstats = kzalloc(sizeof(struct memcg_vmstats), GFP_KERNEL); |
5307 | if (!memcg->vmstats) | |
5308 | goto fail; | |
5309 | ||
3e38e0aa RG |
5310 | memcg->vmstats_percpu = alloc_percpu_gfp(struct memcg_vmstats_percpu, |
5311 | GFP_KERNEL_ACCOUNT); | |
871789d4 | 5312 | if (!memcg->vmstats_percpu) |
0b8f73e1 | 5313 | goto fail; |
78fb7466 | 5314 | |
3ed28fa1 | 5315 | for_each_node(node) |
ef8f2327 | 5316 | if (alloc_mem_cgroup_per_node_info(memcg, node)) |
0b8f73e1 | 5317 | goto fail; |
f64c3f54 | 5318 | |
0b8f73e1 JW |
5319 | if (memcg_wb_domain_init(memcg, GFP_KERNEL)) |
5320 | goto fail; | |
28dbc4b6 | 5321 | |
f7e1cb6e | 5322 | INIT_WORK(&memcg->high_work, high_work_func); |
d142e3e6 | 5323 | INIT_LIST_HEAD(&memcg->oom_notify); |
d142e3e6 GC |
5324 | mutex_init(&memcg->thresholds_lock); |
5325 | spin_lock_init(&memcg->move_lock); | |
70ddf637 | 5326 | vmpressure_init(&memcg->vmpressure); |
fba94807 TH |
5327 | INIT_LIST_HEAD(&memcg->event_list); |
5328 | spin_lock_init(&memcg->event_list_lock); | |
d886f4e4 | 5329 | memcg->socket_pressure = jiffies; |
84c07d11 | 5330 | #ifdef CONFIG_MEMCG_KMEM |
900a38f0 | 5331 | memcg->kmemcg_id = -1; |
bf4f0599 | 5332 | INIT_LIST_HEAD(&memcg->objcg_list); |
900a38f0 | 5333 | #endif |
52ebea74 TH |
5334 | #ifdef CONFIG_CGROUP_WRITEBACK |
5335 | INIT_LIST_HEAD(&memcg->cgwb_list); | |
97b27821 TH |
5336 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) |
5337 | memcg->cgwb_frn[i].done = | |
5338 | __WB_COMPLETION_INIT(&memcg_cgwb_frn_waitq); | |
87eaceb3 YS |
5339 | #endif |
5340 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
5341 | spin_lock_init(&memcg->deferred_split_queue.split_queue_lock); | |
5342 | INIT_LIST_HEAD(&memcg->deferred_split_queue.split_queue); | |
5343 | memcg->deferred_split_queue.split_queue_len = 0; | |
52ebea74 | 5344 | #endif |
ec1c86b2 | 5345 | lru_gen_init_memcg(memcg); |
0b8f73e1 JW |
5346 | return memcg; |
5347 | fail: | |
7e97de0b | 5348 | mem_cgroup_id_remove(memcg); |
40e952f9 | 5349 | __mem_cgroup_free(memcg); |
11d67612 | 5350 | return ERR_PTR(error); |
d142e3e6 GC |
5351 | } |
5352 | ||
0b8f73e1 JW |
5353 | static struct cgroup_subsys_state * __ref |
5354 | mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
d142e3e6 | 5355 | { |
0b8f73e1 | 5356 | struct mem_cgroup *parent = mem_cgroup_from_css(parent_css); |
b87d8cef | 5357 | struct mem_cgroup *memcg, *old_memcg; |
d142e3e6 | 5358 | |
b87d8cef | 5359 | old_memcg = set_active_memcg(parent); |
0b8f73e1 | 5360 | memcg = mem_cgroup_alloc(); |
b87d8cef | 5361 | set_active_memcg(old_memcg); |
11d67612 YS |
5362 | if (IS_ERR(memcg)) |
5363 | return ERR_CAST(memcg); | |
d142e3e6 | 5364 | |
d1663a90 | 5365 | page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX); |
2178e20c | 5366 | WRITE_ONCE(memcg->soft_limit, PAGE_COUNTER_MAX); |
f4840ccf JW |
5367 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
5368 | memcg->zswap_max = PAGE_COUNTER_MAX; | |
5369 | #endif | |
4b82ab4f | 5370 | page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX); |
0b8f73e1 | 5371 | if (parent) { |
82b3aa26 | 5372 | WRITE_ONCE(memcg->swappiness, mem_cgroup_swappiness(parent)); |
17c56de6 | 5373 | WRITE_ONCE(memcg->oom_kill_disable, READ_ONCE(parent->oom_kill_disable)); |
bef8620c | 5374 | |
3e32cb2e | 5375 | page_counter_init(&memcg->memory, &parent->memory); |
37e84351 | 5376 | page_counter_init(&memcg->swap, &parent->swap); |
3e32cb2e | 5377 | page_counter_init(&memcg->kmem, &parent->kmem); |
0db15298 | 5378 | page_counter_init(&memcg->tcpmem, &parent->tcpmem); |
18f59ea7 | 5379 | } else { |
8278f1c7 | 5380 | init_memcg_events(); |
bef8620c RG |
5381 | page_counter_init(&memcg->memory, NULL); |
5382 | page_counter_init(&memcg->swap, NULL); | |
5383 | page_counter_init(&memcg->kmem, NULL); | |
5384 | page_counter_init(&memcg->tcpmem, NULL); | |
d6441637 | 5385 | |
0b8f73e1 JW |
5386 | root_mem_cgroup = memcg; |
5387 | return &memcg->css; | |
5388 | } | |
5389 | ||
f7e1cb6e | 5390 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 5391 | static_branch_inc(&memcg_sockets_enabled_key); |
f7e1cb6e | 5392 | |
b6c1a8af YS |
5393 | #if defined(CONFIG_MEMCG_KMEM) |
5394 | if (!cgroup_memory_nobpf) | |
5395 | static_branch_inc(&memcg_bpf_enabled_key); | |
5396 | #endif | |
5397 | ||
0b8f73e1 | 5398 | return &memcg->css; |
0b8f73e1 JW |
5399 | } |
5400 | ||
73f576c0 | 5401 | static int mem_cgroup_css_online(struct cgroup_subsys_state *css) |
0b8f73e1 | 5402 | { |
58fa2a55 VD |
5403 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
5404 | ||
da0efe30 MS |
5405 | if (memcg_online_kmem(memcg)) |
5406 | goto remove_id; | |
5407 | ||
0a4465d3 | 5408 | /* |
e4262c4f | 5409 | * A memcg must be visible for expand_shrinker_info() |
0a4465d3 KT |
5410 | * by the time the maps are allocated. So, we allocate maps |
5411 | * here, when for_each_mem_cgroup() can't skip it. | |
5412 | */ | |
da0efe30 MS |
5413 | if (alloc_shrinker_info(memcg)) |
5414 | goto offline_kmem; | |
0a4465d3 | 5415 | |
aa48e47e SB |
5416 | if (unlikely(mem_cgroup_is_root(memcg))) |
5417 | queue_delayed_work(system_unbound_wq, &stats_flush_dwork, | |
396faf88 | 5418 | FLUSH_TIME); |
e4dde56c | 5419 | lru_gen_online_memcg(memcg); |
6f0df8e1 JW |
5420 | |
5421 | /* Online state pins memcg ID, memcg ID pins CSS */ | |
5422 | refcount_set(&memcg->id.ref, 1); | |
5423 | css_get(css); | |
5424 | ||
5425 | /* | |
5426 | * Ensure mem_cgroup_from_id() works once we're fully online. | |
5427 | * | |
5428 | * We could do this earlier and require callers to filter with | |
5429 | * css_tryget_online(). But right now there are no users that | |
5430 | * need earlier access, and the workingset code relies on the | |
5431 | * cgroup tree linkage (mem_cgroup_get_nr_swap_pages()). So | |
5432 | * publish it here at the end of onlining. This matches the | |
5433 | * regular ID destruction during offlining. | |
5434 | */ | |
5435 | idr_replace(&mem_cgroup_idr, memcg, memcg->id.id); | |
5436 | ||
2f7dd7a4 | 5437 | return 0; |
da0efe30 MS |
5438 | offline_kmem: |
5439 | memcg_offline_kmem(memcg); | |
5440 | remove_id: | |
5441 | mem_cgroup_id_remove(memcg); | |
5442 | return -ENOMEM; | |
8cdea7c0 BS |
5443 | } |
5444 | ||
eb95419b | 5445 | static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) |
df878fb0 | 5446 | { |
eb95419b | 5447 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 5448 | struct mem_cgroup_event *event, *tmp; |
79bd9814 TH |
5449 | |
5450 | /* | |
5451 | * Unregister events and notify userspace. | |
5452 | * Notify userspace about cgroup removing only after rmdir of cgroup | |
5453 | * directory to avoid race between userspace and kernelspace. | |
5454 | */ | |
4ba9515d | 5455 | spin_lock_irq(&memcg->event_list_lock); |
fba94807 | 5456 | list_for_each_entry_safe(event, tmp, &memcg->event_list, list) { |
79bd9814 TH |
5457 | list_del_init(&event->list); |
5458 | schedule_work(&event->remove); | |
5459 | } | |
4ba9515d | 5460 | spin_unlock_irq(&memcg->event_list_lock); |
ec64f515 | 5461 | |
bf8d5d52 | 5462 | page_counter_set_min(&memcg->memory, 0); |
23067153 | 5463 | page_counter_set_low(&memcg->memory, 0); |
63677c74 | 5464 | |
567e9ab2 | 5465 | memcg_offline_kmem(memcg); |
a178015c | 5466 | reparent_shrinker_deferred(memcg); |
52ebea74 | 5467 | wb_memcg_offline(memcg); |
e4dde56c | 5468 | lru_gen_offline_memcg(memcg); |
73f576c0 | 5469 | |
591edfb1 RG |
5470 | drain_all_stock(memcg); |
5471 | ||
73f576c0 | 5472 | mem_cgroup_id_put(memcg); |
df878fb0 KH |
5473 | } |
5474 | ||
6df38689 VD |
5475 | static void mem_cgroup_css_released(struct cgroup_subsys_state *css) |
5476 | { | |
5477 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5478 | ||
5479 | invalidate_reclaim_iterators(memcg); | |
e4dde56c | 5480 | lru_gen_release_memcg(memcg); |
6df38689 VD |
5481 | } |
5482 | ||
eb95419b | 5483 | static void mem_cgroup_css_free(struct cgroup_subsys_state *css) |
8cdea7c0 | 5484 | { |
eb95419b | 5485 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
97b27821 | 5486 | int __maybe_unused i; |
c268e994 | 5487 | |
97b27821 TH |
5488 | #ifdef CONFIG_CGROUP_WRITEBACK |
5489 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) | |
5490 | wb_wait_for_completion(&memcg->cgwb_frn[i].done); | |
5491 | #endif | |
f7e1cb6e | 5492 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 5493 | static_branch_dec(&memcg_sockets_enabled_key); |
127424c8 | 5494 | |
0db15298 | 5495 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_active) |
d55f90bf | 5496 | static_branch_dec(&memcg_sockets_enabled_key); |
3893e302 | 5497 | |
b6c1a8af YS |
5498 | #if defined(CONFIG_MEMCG_KMEM) |
5499 | if (!cgroup_memory_nobpf) | |
5500 | static_branch_dec(&memcg_bpf_enabled_key); | |
5501 | #endif | |
5502 | ||
0b8f73e1 JW |
5503 | vmpressure_cleanup(&memcg->vmpressure); |
5504 | cancel_work_sync(&memcg->high_work); | |
5505 | mem_cgroup_remove_from_trees(memcg); | |
e4262c4f | 5506 | free_shrinker_info(memcg); |
0b8f73e1 | 5507 | mem_cgroup_free(memcg); |
8cdea7c0 BS |
5508 | } |
5509 | ||
1ced953b TH |
5510 | /** |
5511 | * mem_cgroup_css_reset - reset the states of a mem_cgroup | |
5512 | * @css: the target css | |
5513 | * | |
5514 | * Reset the states of the mem_cgroup associated with @css. This is | |
5515 | * invoked when the userland requests disabling on the default hierarchy | |
5516 | * but the memcg is pinned through dependency. The memcg should stop | |
5517 | * applying policies and should revert to the vanilla state as it may be | |
5518 | * made visible again. | |
5519 | * | |
5520 | * The current implementation only resets the essential configurations. | |
5521 | * This needs to be expanded to cover all the visible parts. | |
5522 | */ | |
5523 | static void mem_cgroup_css_reset(struct cgroup_subsys_state *css) | |
5524 | { | |
5525 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5526 | ||
bbec2e15 RG |
5527 | page_counter_set_max(&memcg->memory, PAGE_COUNTER_MAX); |
5528 | page_counter_set_max(&memcg->swap, PAGE_COUNTER_MAX); | |
bbec2e15 RG |
5529 | page_counter_set_max(&memcg->kmem, PAGE_COUNTER_MAX); |
5530 | page_counter_set_max(&memcg->tcpmem, PAGE_COUNTER_MAX); | |
bf8d5d52 | 5531 | page_counter_set_min(&memcg->memory, 0); |
23067153 | 5532 | page_counter_set_low(&memcg->memory, 0); |
d1663a90 | 5533 | page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX); |
2178e20c | 5534 | WRITE_ONCE(memcg->soft_limit, PAGE_COUNTER_MAX); |
4b82ab4f | 5535 | page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX); |
2529bb3a | 5536 | memcg_wb_domain_size_changed(memcg); |
1ced953b TH |
5537 | } |
5538 | ||
2d146aa3 JW |
5539 | static void mem_cgroup_css_rstat_flush(struct cgroup_subsys_state *css, int cpu) |
5540 | { | |
5541 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5542 | struct mem_cgroup *parent = parent_mem_cgroup(memcg); | |
5543 | struct memcg_vmstats_percpu *statc; | |
f82e6bf9 | 5544 | long delta, delta_cpu, v; |
7e1c0d6f | 5545 | int i, nid; |
2d146aa3 JW |
5546 | |
5547 | statc = per_cpu_ptr(memcg->vmstats_percpu, cpu); | |
5548 | ||
5549 | for (i = 0; i < MEMCG_NR_STAT; i++) { | |
5550 | /* | |
5551 | * Collect the aggregated propagation counts of groups | |
5552 | * below us. We're in a per-cpu loop here and this is | |
5553 | * a global counter, so the first cycle will get them. | |
5554 | */ | |
410f8e82 | 5555 | delta = memcg->vmstats->state_pending[i]; |
2d146aa3 | 5556 | if (delta) |
410f8e82 | 5557 | memcg->vmstats->state_pending[i] = 0; |
2d146aa3 JW |
5558 | |
5559 | /* Add CPU changes on this level since the last flush */ | |
f82e6bf9 | 5560 | delta_cpu = 0; |
2d146aa3 JW |
5561 | v = READ_ONCE(statc->state[i]); |
5562 | if (v != statc->state_prev[i]) { | |
f82e6bf9 YA |
5563 | delta_cpu = v - statc->state_prev[i]; |
5564 | delta += delta_cpu; | |
2d146aa3 JW |
5565 | statc->state_prev[i] = v; |
5566 | } | |
5567 | ||
2d146aa3 | 5568 | /* Aggregate counts on this level and propagate upwards */ |
f82e6bf9 YA |
5569 | if (delta_cpu) |
5570 | memcg->vmstats->state_local[i] += delta_cpu; | |
5571 | ||
5572 | if (delta) { | |
5573 | memcg->vmstats->state[i] += delta; | |
5574 | if (parent) | |
5575 | parent->vmstats->state_pending[i] += delta; | |
5576 | } | |
2d146aa3 JW |
5577 | } |
5578 | ||
8278f1c7 | 5579 | for (i = 0; i < NR_MEMCG_EVENTS; i++) { |
410f8e82 | 5580 | delta = memcg->vmstats->events_pending[i]; |
2d146aa3 | 5581 | if (delta) |
410f8e82 | 5582 | memcg->vmstats->events_pending[i] = 0; |
2d146aa3 | 5583 | |
f82e6bf9 | 5584 | delta_cpu = 0; |
2d146aa3 JW |
5585 | v = READ_ONCE(statc->events[i]); |
5586 | if (v != statc->events_prev[i]) { | |
f82e6bf9 YA |
5587 | delta_cpu = v - statc->events_prev[i]; |
5588 | delta += delta_cpu; | |
2d146aa3 JW |
5589 | statc->events_prev[i] = v; |
5590 | } | |
5591 | ||
f82e6bf9 YA |
5592 | if (delta_cpu) |
5593 | memcg->vmstats->events_local[i] += delta_cpu; | |
2d146aa3 | 5594 | |
f82e6bf9 YA |
5595 | if (delta) { |
5596 | memcg->vmstats->events[i] += delta; | |
5597 | if (parent) | |
5598 | parent->vmstats->events_pending[i] += delta; | |
5599 | } | |
2d146aa3 | 5600 | } |
7e1c0d6f SB |
5601 | |
5602 | for_each_node_state(nid, N_MEMORY) { | |
5603 | struct mem_cgroup_per_node *pn = memcg->nodeinfo[nid]; | |
5604 | struct mem_cgroup_per_node *ppn = NULL; | |
5605 | struct lruvec_stats_percpu *lstatc; | |
5606 | ||
5607 | if (parent) | |
5608 | ppn = parent->nodeinfo[nid]; | |
5609 | ||
5610 | lstatc = per_cpu_ptr(pn->lruvec_stats_percpu, cpu); | |
5611 | ||
5612 | for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { | |
5613 | delta = pn->lruvec_stats.state_pending[i]; | |
5614 | if (delta) | |
5615 | pn->lruvec_stats.state_pending[i] = 0; | |
5616 | ||
f82e6bf9 | 5617 | delta_cpu = 0; |
7e1c0d6f SB |
5618 | v = READ_ONCE(lstatc->state[i]); |
5619 | if (v != lstatc->state_prev[i]) { | |
f82e6bf9 YA |
5620 | delta_cpu = v - lstatc->state_prev[i]; |
5621 | delta += delta_cpu; | |
7e1c0d6f SB |
5622 | lstatc->state_prev[i] = v; |
5623 | } | |
5624 | ||
f82e6bf9 YA |
5625 | if (delta_cpu) |
5626 | pn->lruvec_stats.state_local[i] += delta_cpu; | |
7e1c0d6f | 5627 | |
f82e6bf9 YA |
5628 | if (delta) { |
5629 | pn->lruvec_stats.state[i] += delta; | |
5630 | if (ppn) | |
5631 | ppn->lruvec_stats.state_pending[i] += delta; | |
5632 | } | |
7e1c0d6f SB |
5633 | } |
5634 | } | |
2d146aa3 JW |
5635 | } |
5636 | ||
02491447 | 5637 | #ifdef CONFIG_MMU |
7dc74be0 | 5638 | /* Handlers for move charge at task migration. */ |
854ffa8d | 5639 | static int mem_cgroup_do_precharge(unsigned long count) |
7dc74be0 | 5640 | { |
05b84301 | 5641 | int ret; |
9476db97 | 5642 | |
d0164adc MG |
5643 | /* Try a single bulk charge without reclaim first, kswapd may wake */ |
5644 | ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_DIRECT_RECLAIM, count); | |
9476db97 | 5645 | if (!ret) { |
854ffa8d | 5646 | mc.precharge += count; |
854ffa8d DN |
5647 | return ret; |
5648 | } | |
9476db97 | 5649 | |
3674534b | 5650 | /* Try charges one by one with reclaim, but do not retry */ |
854ffa8d | 5651 | while (count--) { |
3674534b | 5652 | ret = try_charge(mc.to, GFP_KERNEL | __GFP_NORETRY, 1); |
38c5d72f | 5653 | if (ret) |
38c5d72f | 5654 | return ret; |
854ffa8d | 5655 | mc.precharge++; |
9476db97 | 5656 | cond_resched(); |
854ffa8d | 5657 | } |
9476db97 | 5658 | return 0; |
4ffef5fe DN |
5659 | } |
5660 | ||
4ffef5fe DN |
5661 | union mc_target { |
5662 | struct page *page; | |
02491447 | 5663 | swp_entry_t ent; |
4ffef5fe DN |
5664 | }; |
5665 | ||
4ffef5fe | 5666 | enum mc_target_type { |
8d32ff84 | 5667 | MC_TARGET_NONE = 0, |
4ffef5fe | 5668 | MC_TARGET_PAGE, |
02491447 | 5669 | MC_TARGET_SWAP, |
c733a828 | 5670 | MC_TARGET_DEVICE, |
4ffef5fe DN |
5671 | }; |
5672 | ||
90254a65 DN |
5673 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
5674 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 5675 | { |
25b2995a | 5676 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 5677 | |
58f341f7 | 5678 | if (!page) |
90254a65 DN |
5679 | return NULL; |
5680 | if (PageAnon(page)) { | |
1dfab5ab | 5681 | if (!(mc.flags & MOVE_ANON)) |
90254a65 | 5682 | return NULL; |
1dfab5ab JW |
5683 | } else { |
5684 | if (!(mc.flags & MOVE_FILE)) | |
5685 | return NULL; | |
5686 | } | |
58f341f7 | 5687 | get_page(page); |
90254a65 DN |
5688 | |
5689 | return page; | |
5690 | } | |
5691 | ||
c733a828 | 5692 | #if defined(CONFIG_SWAP) || defined(CONFIG_DEVICE_PRIVATE) |
90254a65 | 5693 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, |
48406ef8 | 5694 | pte_t ptent, swp_entry_t *entry) |
90254a65 | 5695 | { |
90254a65 DN |
5696 | struct page *page = NULL; |
5697 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
5698 | ||
9a137153 | 5699 | if (!(mc.flags & MOVE_ANON)) |
90254a65 | 5700 | return NULL; |
c733a828 JG |
5701 | |
5702 | /* | |
27674ef6 CH |
5703 | * Handle device private pages that are not accessible by the CPU, but |
5704 | * stored as special swap entries in the page table. | |
c733a828 JG |
5705 | */ |
5706 | if (is_device_private_entry(ent)) { | |
af5cdaf8 | 5707 | page = pfn_swap_entry_to_page(ent); |
27674ef6 | 5708 | if (!get_page_unless_zero(page)) |
c733a828 JG |
5709 | return NULL; |
5710 | return page; | |
5711 | } | |
5712 | ||
9a137153 RC |
5713 | if (non_swap_entry(ent)) |
5714 | return NULL; | |
5715 | ||
4b91355e | 5716 | /* |
cb691e2f | 5717 | * Because swap_cache_get_folio() updates some statistics counter, |
4b91355e KH |
5718 | * we call find_get_page() with swapper_space directly. |
5719 | */ | |
f6ab1f7f | 5720 | page = find_get_page(swap_address_space(ent), swp_offset(ent)); |
2d1c4980 | 5721 | entry->val = ent.val; |
90254a65 DN |
5722 | |
5723 | return page; | |
5724 | } | |
4b91355e KH |
5725 | #else |
5726 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
48406ef8 | 5727 | pte_t ptent, swp_entry_t *entry) |
4b91355e KH |
5728 | { |
5729 | return NULL; | |
5730 | } | |
5731 | #endif | |
90254a65 | 5732 | |
87946a72 | 5733 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
48384b0b | 5734 | unsigned long addr, pte_t ptent) |
87946a72 | 5735 | { |
524984ff MWO |
5736 | unsigned long index; |
5737 | struct folio *folio; | |
5738 | ||
87946a72 DN |
5739 | if (!vma->vm_file) /* anonymous vma */ |
5740 | return NULL; | |
1dfab5ab | 5741 | if (!(mc.flags & MOVE_FILE)) |
87946a72 DN |
5742 | return NULL; |
5743 | ||
524984ff | 5744 | /* folio is moved even if it's not RSS of this task(page-faulted). */ |
aa3b1895 | 5745 | /* shmem/tmpfs may report page out on swap: account for that too. */ |
524984ff MWO |
5746 | index = linear_page_index(vma, addr); |
5747 | folio = filemap_get_incore_folio(vma->vm_file->f_mapping, index); | |
66dabbb6 | 5748 | if (IS_ERR(folio)) |
524984ff MWO |
5749 | return NULL; |
5750 | return folio_file_page(folio, index); | |
87946a72 DN |
5751 | } |
5752 | ||
b1b0deab CG |
5753 | /** |
5754 | * mem_cgroup_move_account - move account of the page | |
5755 | * @page: the page | |
25843c2b | 5756 | * @compound: charge the page as compound or small page |
b1b0deab CG |
5757 | * @from: mem_cgroup which the page is moved from. |
5758 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
5759 | * | |
4e0cf05f | 5760 | * The page must be locked and not on the LRU. |
b1b0deab CG |
5761 | * |
5762 | * This function doesn't do "charge" to new cgroup and doesn't do "uncharge" | |
5763 | * from old cgroup. | |
5764 | */ | |
5765 | static int mem_cgroup_move_account(struct page *page, | |
f627c2f5 | 5766 | bool compound, |
b1b0deab CG |
5767 | struct mem_cgroup *from, |
5768 | struct mem_cgroup *to) | |
5769 | { | |
fcce4672 | 5770 | struct folio *folio = page_folio(page); |
ae8af438 KK |
5771 | struct lruvec *from_vec, *to_vec; |
5772 | struct pglist_data *pgdat; | |
fcce4672 | 5773 | unsigned int nr_pages = compound ? folio_nr_pages(folio) : 1; |
8e88bd2d | 5774 | int nid, ret; |
b1b0deab CG |
5775 | |
5776 | VM_BUG_ON(from == to); | |
4e0cf05f | 5777 | VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); |
fcce4672 | 5778 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
9c325215 | 5779 | VM_BUG_ON(compound && !folio_test_large(folio)); |
b1b0deab | 5780 | |
b1b0deab | 5781 | ret = -EINVAL; |
fcce4672 | 5782 | if (folio_memcg(folio) != from) |
4e0cf05f | 5783 | goto out; |
b1b0deab | 5784 | |
fcce4672 | 5785 | pgdat = folio_pgdat(folio); |
867e5e1d JW |
5786 | from_vec = mem_cgroup_lruvec(from, pgdat); |
5787 | to_vec = mem_cgroup_lruvec(to, pgdat); | |
ae8af438 | 5788 | |
fcce4672 | 5789 | folio_memcg_lock(folio); |
b1b0deab | 5790 | |
fcce4672 MWO |
5791 | if (folio_test_anon(folio)) { |
5792 | if (folio_mapped(folio)) { | |
be5d0a74 JW |
5793 | __mod_lruvec_state(from_vec, NR_ANON_MAPPED, -nr_pages); |
5794 | __mod_lruvec_state(to_vec, NR_ANON_MAPPED, nr_pages); | |
6199277b | 5795 | if (folio_test_pmd_mappable(folio)) { |
69473e5d MS |
5796 | __mod_lruvec_state(from_vec, NR_ANON_THPS, |
5797 | -nr_pages); | |
5798 | __mod_lruvec_state(to_vec, NR_ANON_THPS, | |
5799 | nr_pages); | |
468c3982 | 5800 | } |
be5d0a74 JW |
5801 | } |
5802 | } else { | |
0d1c2072 JW |
5803 | __mod_lruvec_state(from_vec, NR_FILE_PAGES, -nr_pages); |
5804 | __mod_lruvec_state(to_vec, NR_FILE_PAGES, nr_pages); | |
5805 | ||
fcce4672 | 5806 | if (folio_test_swapbacked(folio)) { |
0d1c2072 JW |
5807 | __mod_lruvec_state(from_vec, NR_SHMEM, -nr_pages); |
5808 | __mod_lruvec_state(to_vec, NR_SHMEM, nr_pages); | |
5809 | } | |
5810 | ||
fcce4672 | 5811 | if (folio_mapped(folio)) { |
49e50d27 JW |
5812 | __mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages); |
5813 | __mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages); | |
5814 | } | |
b1b0deab | 5815 | |
fcce4672 MWO |
5816 | if (folio_test_dirty(folio)) { |
5817 | struct address_space *mapping = folio_mapping(folio); | |
c4843a75 | 5818 | |
f56753ac | 5819 | if (mapping_can_writeback(mapping)) { |
49e50d27 JW |
5820 | __mod_lruvec_state(from_vec, NR_FILE_DIRTY, |
5821 | -nr_pages); | |
5822 | __mod_lruvec_state(to_vec, NR_FILE_DIRTY, | |
5823 | nr_pages); | |
5824 | } | |
c4843a75 GT |
5825 | } |
5826 | } | |
5827 | ||
c449deb2 HD |
5828 | #ifdef CONFIG_SWAP |
5829 | if (folio_test_swapcache(folio)) { | |
5830 | __mod_lruvec_state(from_vec, NR_SWAPCACHE, -nr_pages); | |
5831 | __mod_lruvec_state(to_vec, NR_SWAPCACHE, nr_pages); | |
5832 | } | |
5833 | #endif | |
fcce4672 | 5834 | if (folio_test_writeback(folio)) { |
ae8af438 KK |
5835 | __mod_lruvec_state(from_vec, NR_WRITEBACK, -nr_pages); |
5836 | __mod_lruvec_state(to_vec, NR_WRITEBACK, nr_pages); | |
b1b0deab CG |
5837 | } |
5838 | ||
5839 | /* | |
abb242f5 JW |
5840 | * All state has been migrated, let's switch to the new memcg. |
5841 | * | |
bcfe06bf | 5842 | * It is safe to change page's memcg here because the page |
abb242f5 JW |
5843 | * is referenced, charged, isolated, and locked: we can't race |
5844 | * with (un)charging, migration, LRU putback, or anything else | |
bcfe06bf | 5845 | * that would rely on a stable page's memory cgroup. |
abb242f5 | 5846 | * |
6c77b607 | 5847 | * Note that folio_memcg_lock is a memcg lock, not a page lock, |
bcfe06bf | 5848 | * to save space. As soon as we switch page's memory cgroup to a |
abb242f5 JW |
5849 | * new memcg that isn't locked, the above state can change |
5850 | * concurrently again. Make sure we're truly done with it. | |
b1b0deab | 5851 | */ |
abb242f5 | 5852 | smp_mb(); |
b1b0deab | 5853 | |
1a3e1f40 JW |
5854 | css_get(&to->css); |
5855 | css_put(&from->css); | |
5856 | ||
fcce4672 | 5857 | folio->memcg_data = (unsigned long)to; |
87eaceb3 | 5858 | |
f70ad448 | 5859 | __folio_memcg_unlock(from); |
b1b0deab CG |
5860 | |
5861 | ret = 0; | |
fcce4672 | 5862 | nid = folio_nid(folio); |
b1b0deab CG |
5863 | |
5864 | local_irq_disable(); | |
6e0110c2 | 5865 | mem_cgroup_charge_statistics(to, nr_pages); |
8e88bd2d | 5866 | memcg_check_events(to, nid); |
6e0110c2 | 5867 | mem_cgroup_charge_statistics(from, -nr_pages); |
8e88bd2d | 5868 | memcg_check_events(from, nid); |
b1b0deab | 5869 | local_irq_enable(); |
b1b0deab CG |
5870 | out: |
5871 | return ret; | |
5872 | } | |
5873 | ||
7cf7806c LR |
5874 | /** |
5875 | * get_mctgt_type - get target type of moving charge | |
5876 | * @vma: the vma the pte to be checked belongs | |
5877 | * @addr: the address corresponding to the pte to be checked | |
5878 | * @ptent: the pte to be checked | |
5879 | * @target: the pointer the target page or swap ent will be stored(can be NULL) | |
5880 | * | |
853f62a3 MWO |
5881 | * Context: Called with pte lock held. |
5882 | * Return: | |
5883 | * * MC_TARGET_NONE - If the pte is not a target for move charge. | |
5884 | * * MC_TARGET_PAGE - If the page corresponding to this pte is a target for | |
5885 | * move charge. If @target is not NULL, the page is stored in target->page | |
5886 | * with extra refcnt taken (Caller should release it). | |
5887 | * * MC_TARGET_SWAP - If the swap entry corresponding to this pte is a | |
5888 | * target for charge migration. If @target is not NULL, the entry is | |
5889 | * stored in target->ent. | |
5890 | * * MC_TARGET_DEVICE - Like MC_TARGET_PAGE but page is device memory and | |
5891 | * thus not on the lru. For now such page is charged like a regular page | |
5892 | * would be as it is just special memory taking the place of a regular page. | |
5893 | * See Documentations/vm/hmm.txt and include/linux/hmm.h | |
7cf7806c | 5894 | */ |
8d32ff84 | 5895 | static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, |
90254a65 DN |
5896 | unsigned long addr, pte_t ptent, union mc_target *target) |
5897 | { | |
5898 | struct page *page = NULL; | |
8d32ff84 | 5899 | enum mc_target_type ret = MC_TARGET_NONE; |
90254a65 DN |
5900 | swp_entry_t ent = { .val = 0 }; |
5901 | ||
5902 | if (pte_present(ptent)) | |
5903 | page = mc_handle_present_pte(vma, addr, ptent); | |
5c041f5d PX |
5904 | else if (pte_none_mostly(ptent)) |
5905 | /* | |
5906 | * PTE markers should be treated as a none pte here, separated | |
5907 | * from other swap handling below. | |
5908 | */ | |
5909 | page = mc_handle_file_pte(vma, addr, ptent); | |
90254a65 | 5910 | else if (is_swap_pte(ptent)) |
48406ef8 | 5911 | page = mc_handle_swap_pte(vma, ptent, &ent); |
90254a65 | 5912 | |
4e0cf05f JW |
5913 | if (target && page) { |
5914 | if (!trylock_page(page)) { | |
5915 | put_page(page); | |
5916 | return ret; | |
5917 | } | |
5918 | /* | |
5919 | * page_mapped() must be stable during the move. This | |
5920 | * pte is locked, so if it's present, the page cannot | |
5921 | * become unmapped. If it isn't, we have only partial | |
5922 | * control over the mapped state: the page lock will | |
5923 | * prevent new faults against pagecache and swapcache, | |
5924 | * so an unmapped page cannot become mapped. However, | |
5925 | * if the page is already mapped elsewhere, it can | |
5926 | * unmap, and there is nothing we can do about it. | |
5927 | * Alas, skip moving the page in this case. | |
5928 | */ | |
5929 | if (!pte_present(ptent) && page_mapped(page)) { | |
5930 | unlock_page(page); | |
5931 | put_page(page); | |
5932 | return ret; | |
5933 | } | |
5934 | } | |
5935 | ||
90254a65 | 5936 | if (!page && !ent.val) |
8d32ff84 | 5937 | return ret; |
02491447 | 5938 | if (page) { |
02491447 | 5939 | /* |
0a31bc97 | 5940 | * Do only loose check w/o serialization. |
1306a85a | 5941 | * mem_cgroup_move_account() checks the page is valid or |
0a31bc97 | 5942 | * not under LRU exclusion. |
02491447 | 5943 | */ |
bcfe06bf | 5944 | if (page_memcg(page) == mc.from) { |
02491447 | 5945 | ret = MC_TARGET_PAGE; |
f25cbb7a AS |
5946 | if (is_device_private_page(page) || |
5947 | is_device_coherent_page(page)) | |
c733a828 | 5948 | ret = MC_TARGET_DEVICE; |
02491447 DN |
5949 | if (target) |
5950 | target->page = page; | |
5951 | } | |
4e0cf05f JW |
5952 | if (!ret || !target) { |
5953 | if (target) | |
5954 | unlock_page(page); | |
02491447 | 5955 | put_page(page); |
4e0cf05f | 5956 | } |
02491447 | 5957 | } |
3e14a57b HY |
5958 | /* |
5959 | * There is a swap entry and a page doesn't exist or isn't charged. | |
5960 | * But we cannot move a tail-page in a THP. | |
5961 | */ | |
5962 | if (ent.val && !ret && (!page || !PageTransCompound(page)) && | |
34c00c31 | 5963 | mem_cgroup_id(mc.from) == lookup_swap_cgroup_id(ent)) { |
7f0f1546 KH |
5964 | ret = MC_TARGET_SWAP; |
5965 | if (target) | |
5966 | target->ent = ent; | |
4ffef5fe | 5967 | } |
4ffef5fe DN |
5968 | return ret; |
5969 | } | |
5970 | ||
12724850 NH |
5971 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
5972 | /* | |
d6810d73 HY |
5973 | * We don't consider PMD mapped swapping or file mapped pages because THP does |
5974 | * not support them for now. | |
12724850 NH |
5975 | * Caller should make sure that pmd_trans_huge(pmd) is true. |
5976 | */ | |
5977 | static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
5978 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
5979 | { | |
5980 | struct page *page = NULL; | |
12724850 NH |
5981 | enum mc_target_type ret = MC_TARGET_NONE; |
5982 | ||
84c3fc4e ZY |
5983 | if (unlikely(is_swap_pmd(pmd))) { |
5984 | VM_BUG_ON(thp_migration_supported() && | |
5985 | !is_pmd_migration_entry(pmd)); | |
5986 | return ret; | |
5987 | } | |
12724850 | 5988 | page = pmd_page(pmd); |
309381fe | 5989 | VM_BUG_ON_PAGE(!page || !PageHead(page), page); |
1dfab5ab | 5990 | if (!(mc.flags & MOVE_ANON)) |
12724850 | 5991 | return ret; |
bcfe06bf | 5992 | if (page_memcg(page) == mc.from) { |
12724850 NH |
5993 | ret = MC_TARGET_PAGE; |
5994 | if (target) { | |
5995 | get_page(page); | |
4e0cf05f JW |
5996 | if (!trylock_page(page)) { |
5997 | put_page(page); | |
5998 | return MC_TARGET_NONE; | |
5999 | } | |
12724850 NH |
6000 | target->page = page; |
6001 | } | |
6002 | } | |
6003 | return ret; | |
6004 | } | |
6005 | #else | |
6006 | static inline enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
6007 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
6008 | { | |
6009 | return MC_TARGET_NONE; | |
6010 | } | |
6011 | #endif | |
6012 | ||
4ffef5fe DN |
6013 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, |
6014 | unsigned long addr, unsigned long end, | |
6015 | struct mm_walk *walk) | |
6016 | { | |
26bcd64a | 6017 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
6018 | pte_t *pte; |
6019 | spinlock_t *ptl; | |
6020 | ||
b6ec57f4 KS |
6021 | ptl = pmd_trans_huge_lock(pmd, vma); |
6022 | if (ptl) { | |
c733a828 JG |
6023 | /* |
6024 | * Note their can not be MC_TARGET_DEVICE for now as we do not | |
25b2995a CH |
6025 | * support transparent huge page with MEMORY_DEVICE_PRIVATE but |
6026 | * this might change. | |
c733a828 | 6027 | */ |
12724850 NH |
6028 | if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE) |
6029 | mc.precharge += HPAGE_PMD_NR; | |
bf929152 | 6030 | spin_unlock(ptl); |
1a5a9906 | 6031 | return 0; |
12724850 | 6032 | } |
03319327 | 6033 | |
4ffef5fe | 6034 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
04dee9e8 HD |
6035 | if (!pte) |
6036 | return 0; | |
4ffef5fe | 6037 | for (; addr != end; pte++, addr += PAGE_SIZE) |
c33c7948 | 6038 | if (get_mctgt_type(vma, addr, ptep_get(pte), NULL)) |
4ffef5fe DN |
6039 | mc.precharge++; /* increment precharge temporarily */ |
6040 | pte_unmap_unlock(pte - 1, ptl); | |
6041 | cond_resched(); | |
6042 | ||
7dc74be0 DN |
6043 | return 0; |
6044 | } | |
6045 | ||
7b86ac33 CH |
6046 | static const struct mm_walk_ops precharge_walk_ops = { |
6047 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
49b06385 | 6048 | .walk_lock = PGWALK_RDLOCK, |
7b86ac33 CH |
6049 | }; |
6050 | ||
4ffef5fe DN |
6051 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
6052 | { | |
6053 | unsigned long precharge; | |
4ffef5fe | 6054 | |
d8ed45c5 | 6055 | mmap_read_lock(mm); |
ba0aff8e | 6056 | walk_page_range(mm, 0, ULONG_MAX, &precharge_walk_ops, NULL); |
d8ed45c5 | 6057 | mmap_read_unlock(mm); |
4ffef5fe DN |
6058 | |
6059 | precharge = mc.precharge; | |
6060 | mc.precharge = 0; | |
6061 | ||
6062 | return precharge; | |
6063 | } | |
6064 | ||
4ffef5fe DN |
6065 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
6066 | { | |
dfe076b0 DN |
6067 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
6068 | ||
6069 | VM_BUG_ON(mc.moving_task); | |
6070 | mc.moving_task = current; | |
6071 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
6072 | } |
6073 | ||
dfe076b0 DN |
6074 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
6075 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 6076 | { |
2bd9bb20 KH |
6077 | struct mem_cgroup *from = mc.from; |
6078 | struct mem_cgroup *to = mc.to; | |
6079 | ||
4ffef5fe | 6080 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d | 6081 | if (mc.precharge) { |
00501b53 | 6082 | cancel_charge(mc.to, mc.precharge); |
854ffa8d DN |
6083 | mc.precharge = 0; |
6084 | } | |
6085 | /* | |
6086 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
6087 | * we must uncharge here. | |
6088 | */ | |
6089 | if (mc.moved_charge) { | |
00501b53 | 6090 | cancel_charge(mc.from, mc.moved_charge); |
854ffa8d | 6091 | mc.moved_charge = 0; |
4ffef5fe | 6092 | } |
483c30b5 DN |
6093 | /* we must fixup refcnts and charges */ |
6094 | if (mc.moved_swap) { | |
483c30b5 | 6095 | /* uncharge swap account from the old cgroup */ |
ce00a967 | 6096 | if (!mem_cgroup_is_root(mc.from)) |
3e32cb2e | 6097 | page_counter_uncharge(&mc.from->memsw, mc.moved_swap); |
483c30b5 | 6098 | |
615d66c3 VD |
6099 | mem_cgroup_id_put_many(mc.from, mc.moved_swap); |
6100 | ||
05b84301 | 6101 | /* |
3e32cb2e JW |
6102 | * we charged both to->memory and to->memsw, so we |
6103 | * should uncharge to->memory. | |
05b84301 | 6104 | */ |
ce00a967 | 6105 | if (!mem_cgroup_is_root(mc.to)) |
3e32cb2e JW |
6106 | page_counter_uncharge(&mc.to->memory, mc.moved_swap); |
6107 | ||
483c30b5 DN |
6108 | mc.moved_swap = 0; |
6109 | } | |
dfe076b0 DN |
6110 | memcg_oom_recover(from); |
6111 | memcg_oom_recover(to); | |
6112 | wake_up_all(&mc.waitq); | |
6113 | } | |
6114 | ||
6115 | static void mem_cgroup_clear_mc(void) | |
6116 | { | |
264a0ae1 TH |
6117 | struct mm_struct *mm = mc.mm; |
6118 | ||
dfe076b0 DN |
6119 | /* |
6120 | * we must clear moving_task before waking up waiters at the end of | |
6121 | * task migration. | |
6122 | */ | |
6123 | mc.moving_task = NULL; | |
6124 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 6125 | spin_lock(&mc.lock); |
4ffef5fe DN |
6126 | mc.from = NULL; |
6127 | mc.to = NULL; | |
264a0ae1 | 6128 | mc.mm = NULL; |
2bd9bb20 | 6129 | spin_unlock(&mc.lock); |
264a0ae1 TH |
6130 | |
6131 | mmput(mm); | |
4ffef5fe DN |
6132 | } |
6133 | ||
1f7dd3e5 | 6134 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
7dc74be0 | 6135 | { |
1f7dd3e5 | 6136 | struct cgroup_subsys_state *css; |
eed67d75 | 6137 | struct mem_cgroup *memcg = NULL; /* unneeded init to make gcc happy */ |
9f2115f9 | 6138 | struct mem_cgroup *from; |
4530eddb | 6139 | struct task_struct *leader, *p; |
9f2115f9 | 6140 | struct mm_struct *mm; |
1dfab5ab | 6141 | unsigned long move_flags; |
9f2115f9 | 6142 | int ret = 0; |
7dc74be0 | 6143 | |
1f7dd3e5 TH |
6144 | /* charge immigration isn't supported on the default hierarchy */ |
6145 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
9f2115f9 TH |
6146 | return 0; |
6147 | ||
4530eddb TH |
6148 | /* |
6149 | * Multi-process migrations only happen on the default hierarchy | |
6150 | * where charge immigration is not used. Perform charge | |
6151 | * immigration if @tset contains a leader and whine if there are | |
6152 | * multiple. | |
6153 | */ | |
6154 | p = NULL; | |
1f7dd3e5 | 6155 | cgroup_taskset_for_each_leader(leader, css, tset) { |
4530eddb TH |
6156 | WARN_ON_ONCE(p); |
6157 | p = leader; | |
1f7dd3e5 | 6158 | memcg = mem_cgroup_from_css(css); |
4530eddb TH |
6159 | } |
6160 | if (!p) | |
6161 | return 0; | |
6162 | ||
1f7dd3e5 | 6163 | /* |
f0953a1b | 6164 | * We are now committed to this value whatever it is. Changes in this |
1f7dd3e5 TH |
6165 | * tunable will only affect upcoming migrations, not the current one. |
6166 | * So we need to save it, and keep it going. | |
6167 | */ | |
6168 | move_flags = READ_ONCE(memcg->move_charge_at_immigrate); | |
6169 | if (!move_flags) | |
6170 | return 0; | |
6171 | ||
9f2115f9 TH |
6172 | from = mem_cgroup_from_task(p); |
6173 | ||
6174 | VM_BUG_ON(from == memcg); | |
6175 | ||
6176 | mm = get_task_mm(p); | |
6177 | if (!mm) | |
6178 | return 0; | |
6179 | /* We move charges only when we move a owner of the mm */ | |
6180 | if (mm->owner == p) { | |
6181 | VM_BUG_ON(mc.from); | |
6182 | VM_BUG_ON(mc.to); | |
6183 | VM_BUG_ON(mc.precharge); | |
6184 | VM_BUG_ON(mc.moved_charge); | |
6185 | VM_BUG_ON(mc.moved_swap); | |
6186 | ||
6187 | spin_lock(&mc.lock); | |
264a0ae1 | 6188 | mc.mm = mm; |
9f2115f9 TH |
6189 | mc.from = from; |
6190 | mc.to = memcg; | |
6191 | mc.flags = move_flags; | |
6192 | spin_unlock(&mc.lock); | |
6193 | /* We set mc.moving_task later */ | |
6194 | ||
6195 | ret = mem_cgroup_precharge_mc(mm); | |
6196 | if (ret) | |
6197 | mem_cgroup_clear_mc(); | |
264a0ae1 TH |
6198 | } else { |
6199 | mmput(mm); | |
7dc74be0 DN |
6200 | } |
6201 | return ret; | |
6202 | } | |
6203 | ||
1f7dd3e5 | 6204 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
7dc74be0 | 6205 | { |
4e2f245d JW |
6206 | if (mc.to) |
6207 | mem_cgroup_clear_mc(); | |
7dc74be0 DN |
6208 | } |
6209 | ||
4ffef5fe DN |
6210 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
6211 | unsigned long addr, unsigned long end, | |
6212 | struct mm_walk *walk) | |
7dc74be0 | 6213 | { |
4ffef5fe | 6214 | int ret = 0; |
26bcd64a | 6215 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
6216 | pte_t *pte; |
6217 | spinlock_t *ptl; | |
12724850 NH |
6218 | enum mc_target_type target_type; |
6219 | union mc_target target; | |
6220 | struct page *page; | |
4ffef5fe | 6221 | |
b6ec57f4 KS |
6222 | ptl = pmd_trans_huge_lock(pmd, vma); |
6223 | if (ptl) { | |
62ade86a | 6224 | if (mc.precharge < HPAGE_PMD_NR) { |
bf929152 | 6225 | spin_unlock(ptl); |
12724850 NH |
6226 | return 0; |
6227 | } | |
6228 | target_type = get_mctgt_type_thp(vma, addr, *pmd, &target); | |
6229 | if (target_type == MC_TARGET_PAGE) { | |
6230 | page = target.page; | |
f7f9c00d | 6231 | if (isolate_lru_page(page)) { |
f627c2f5 | 6232 | if (!mem_cgroup_move_account(page, true, |
1306a85a | 6233 | mc.from, mc.to)) { |
12724850 NH |
6234 | mc.precharge -= HPAGE_PMD_NR; |
6235 | mc.moved_charge += HPAGE_PMD_NR; | |
6236 | } | |
6237 | putback_lru_page(page); | |
6238 | } | |
4e0cf05f | 6239 | unlock_page(page); |
12724850 | 6240 | put_page(page); |
c733a828 JG |
6241 | } else if (target_type == MC_TARGET_DEVICE) { |
6242 | page = target.page; | |
6243 | if (!mem_cgroup_move_account(page, true, | |
6244 | mc.from, mc.to)) { | |
6245 | mc.precharge -= HPAGE_PMD_NR; | |
6246 | mc.moved_charge += HPAGE_PMD_NR; | |
6247 | } | |
4e0cf05f | 6248 | unlock_page(page); |
c733a828 | 6249 | put_page(page); |
12724850 | 6250 | } |
bf929152 | 6251 | spin_unlock(ptl); |
1a5a9906 | 6252 | return 0; |
12724850 NH |
6253 | } |
6254 | ||
4ffef5fe DN |
6255 | retry: |
6256 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
04dee9e8 HD |
6257 | if (!pte) |
6258 | return 0; | |
4ffef5fe | 6259 | for (; addr != end; addr += PAGE_SIZE) { |
c33c7948 | 6260 | pte_t ptent = ptep_get(pte++); |
c733a828 | 6261 | bool device = false; |
02491447 | 6262 | swp_entry_t ent; |
4ffef5fe DN |
6263 | |
6264 | if (!mc.precharge) | |
6265 | break; | |
6266 | ||
8d32ff84 | 6267 | switch (get_mctgt_type(vma, addr, ptent, &target)) { |
c733a828 JG |
6268 | case MC_TARGET_DEVICE: |
6269 | device = true; | |
e4a9bc58 | 6270 | fallthrough; |
4ffef5fe DN |
6271 | case MC_TARGET_PAGE: |
6272 | page = target.page; | |
53f9263b KS |
6273 | /* |
6274 | * We can have a part of the split pmd here. Moving it | |
6275 | * can be done but it would be too convoluted so simply | |
6276 | * ignore such a partial THP and keep it in original | |
6277 | * memcg. There should be somebody mapping the head. | |
6278 | */ | |
6279 | if (PageTransCompound(page)) | |
6280 | goto put; | |
f7f9c00d | 6281 | if (!device && !isolate_lru_page(page)) |
4ffef5fe | 6282 | goto put; |
f627c2f5 KS |
6283 | if (!mem_cgroup_move_account(page, false, |
6284 | mc.from, mc.to)) { | |
4ffef5fe | 6285 | mc.precharge--; |
854ffa8d DN |
6286 | /* we uncharge from mc.from later. */ |
6287 | mc.moved_charge++; | |
4ffef5fe | 6288 | } |
c733a828 JG |
6289 | if (!device) |
6290 | putback_lru_page(page); | |
4e0cf05f JW |
6291 | put: /* get_mctgt_type() gets & locks the page */ |
6292 | unlock_page(page); | |
4ffef5fe DN |
6293 | put_page(page); |
6294 | break; | |
02491447 DN |
6295 | case MC_TARGET_SWAP: |
6296 | ent = target.ent; | |
e91cbb42 | 6297 | if (!mem_cgroup_move_swap_account(ent, mc.from, mc.to)) { |
02491447 | 6298 | mc.precharge--; |
8d22a935 HD |
6299 | mem_cgroup_id_get_many(mc.to, 1); |
6300 | /* we fixup other refcnts and charges later. */ | |
483c30b5 DN |
6301 | mc.moved_swap++; |
6302 | } | |
02491447 | 6303 | break; |
4ffef5fe DN |
6304 | default: |
6305 | break; | |
6306 | } | |
6307 | } | |
6308 | pte_unmap_unlock(pte - 1, ptl); | |
6309 | cond_resched(); | |
6310 | ||
6311 | if (addr != end) { | |
6312 | /* | |
6313 | * We have consumed all precharges we got in can_attach(). | |
6314 | * We try charge one by one, but don't do any additional | |
6315 | * charges to mc.to if we have failed in charge once in attach() | |
6316 | * phase. | |
6317 | */ | |
854ffa8d | 6318 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
6319 | if (!ret) |
6320 | goto retry; | |
6321 | } | |
6322 | ||
6323 | return ret; | |
6324 | } | |
6325 | ||
7b86ac33 CH |
6326 | static const struct mm_walk_ops charge_walk_ops = { |
6327 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
49b06385 | 6328 | .walk_lock = PGWALK_RDLOCK, |
7b86ac33 CH |
6329 | }; |
6330 | ||
264a0ae1 | 6331 | static void mem_cgroup_move_charge(void) |
4ffef5fe | 6332 | { |
4ffef5fe | 6333 | lru_add_drain_all(); |
312722cb | 6334 | /* |
6c77b607 | 6335 | * Signal folio_memcg_lock() to take the memcg's move_lock |
81f8c3a4 JW |
6336 | * while we're moving its pages to another memcg. Then wait |
6337 | * for already started RCU-only updates to finish. | |
312722cb JW |
6338 | */ |
6339 | atomic_inc(&mc.from->moving_account); | |
6340 | synchronize_rcu(); | |
dfe076b0 | 6341 | retry: |
d8ed45c5 | 6342 | if (unlikely(!mmap_read_trylock(mc.mm))) { |
dfe076b0 | 6343 | /* |
c1e8d7c6 | 6344 | * Someone who are holding the mmap_lock might be waiting in |
dfe076b0 DN |
6345 | * waitq. So we cancel all extra charges, wake up all waiters, |
6346 | * and retry. Because we cancel precharges, we might not be able | |
6347 | * to move enough charges, but moving charge is a best-effort | |
6348 | * feature anyway, so it wouldn't be a big problem. | |
6349 | */ | |
6350 | __mem_cgroup_clear_mc(); | |
6351 | cond_resched(); | |
6352 | goto retry; | |
6353 | } | |
26bcd64a NH |
6354 | /* |
6355 | * When we have consumed all precharges and failed in doing | |
6356 | * additional charge, the page walk just aborts. | |
6357 | */ | |
ba0aff8e | 6358 | walk_page_range(mc.mm, 0, ULONG_MAX, &charge_walk_ops, NULL); |
d8ed45c5 | 6359 | mmap_read_unlock(mc.mm); |
312722cb | 6360 | atomic_dec(&mc.from->moving_account); |
7dc74be0 DN |
6361 | } |
6362 | ||
264a0ae1 | 6363 | static void mem_cgroup_move_task(void) |
67e465a7 | 6364 | { |
264a0ae1 TH |
6365 | if (mc.to) { |
6366 | mem_cgroup_move_charge(); | |
a433658c | 6367 | mem_cgroup_clear_mc(); |
264a0ae1 | 6368 | } |
67e465a7 | 6369 | } |
5cfb80a7 | 6370 | #else /* !CONFIG_MMU */ |
1f7dd3e5 | 6371 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
6372 | { |
6373 | return 0; | |
6374 | } | |
1f7dd3e5 | 6375 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
6376 | { |
6377 | } | |
264a0ae1 | 6378 | static void mem_cgroup_move_task(void) |
5cfb80a7 DN |
6379 | { |
6380 | } | |
6381 | #endif | |
67e465a7 | 6382 | |
bd74fdae YZ |
6383 | #ifdef CONFIG_LRU_GEN |
6384 | static void mem_cgroup_attach(struct cgroup_taskset *tset) | |
6385 | { | |
6386 | struct task_struct *task; | |
6387 | struct cgroup_subsys_state *css; | |
6388 | ||
6389 | /* find the first leader if there is any */ | |
6390 | cgroup_taskset_for_each_leader(task, css, tset) | |
6391 | break; | |
6392 | ||
6393 | if (!task) | |
6394 | return; | |
6395 | ||
6396 | task_lock(task); | |
6397 | if (task->mm && READ_ONCE(task->mm->owner) == task) | |
6398 | lru_gen_migrate_mm(task->mm); | |
6399 | task_unlock(task); | |
6400 | } | |
6401 | #else | |
6402 | static void mem_cgroup_attach(struct cgroup_taskset *tset) | |
6403 | { | |
6404 | } | |
6405 | #endif /* CONFIG_LRU_GEN */ | |
6406 | ||
677dc973 CD |
6407 | static int seq_puts_memcg_tunable(struct seq_file *m, unsigned long value) |
6408 | { | |
6409 | if (value == PAGE_COUNTER_MAX) | |
6410 | seq_puts(m, "max\n"); | |
6411 | else | |
6412 | seq_printf(m, "%llu\n", (u64)value * PAGE_SIZE); | |
6413 | ||
6414 | return 0; | |
6415 | } | |
6416 | ||
241994ed JW |
6417 | static u64 memory_current_read(struct cgroup_subsys_state *css, |
6418 | struct cftype *cft) | |
6419 | { | |
f5fc3c5d JW |
6420 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
6421 | ||
6422 | return (u64)page_counter_read(&memcg->memory) * PAGE_SIZE; | |
241994ed JW |
6423 | } |
6424 | ||
8e20d4b3 GR |
6425 | static u64 memory_peak_read(struct cgroup_subsys_state *css, |
6426 | struct cftype *cft) | |
6427 | { | |
6428 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
6429 | ||
6430 | return (u64)memcg->memory.watermark * PAGE_SIZE; | |
6431 | } | |
6432 | ||
bf8d5d52 RG |
6433 | static int memory_min_show(struct seq_file *m, void *v) |
6434 | { | |
677dc973 CD |
6435 | return seq_puts_memcg_tunable(m, |
6436 | READ_ONCE(mem_cgroup_from_seq(m)->memory.min)); | |
bf8d5d52 RG |
6437 | } |
6438 | ||
6439 | static ssize_t memory_min_write(struct kernfs_open_file *of, | |
6440 | char *buf, size_t nbytes, loff_t off) | |
6441 | { | |
6442 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6443 | unsigned long min; | |
6444 | int err; | |
6445 | ||
6446 | buf = strstrip(buf); | |
6447 | err = page_counter_memparse(buf, "max", &min); | |
6448 | if (err) | |
6449 | return err; | |
6450 | ||
6451 | page_counter_set_min(&memcg->memory, min); | |
6452 | ||
6453 | return nbytes; | |
6454 | } | |
6455 | ||
241994ed JW |
6456 | static int memory_low_show(struct seq_file *m, void *v) |
6457 | { | |
677dc973 CD |
6458 | return seq_puts_memcg_tunable(m, |
6459 | READ_ONCE(mem_cgroup_from_seq(m)->memory.low)); | |
241994ed JW |
6460 | } |
6461 | ||
6462 | static ssize_t memory_low_write(struct kernfs_open_file *of, | |
6463 | char *buf, size_t nbytes, loff_t off) | |
6464 | { | |
6465 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6466 | unsigned long low; | |
6467 | int err; | |
6468 | ||
6469 | buf = strstrip(buf); | |
d2973697 | 6470 | err = page_counter_memparse(buf, "max", &low); |
241994ed JW |
6471 | if (err) |
6472 | return err; | |
6473 | ||
23067153 | 6474 | page_counter_set_low(&memcg->memory, low); |
241994ed JW |
6475 | |
6476 | return nbytes; | |
6477 | } | |
6478 | ||
6479 | static int memory_high_show(struct seq_file *m, void *v) | |
6480 | { | |
d1663a90 JK |
6481 | return seq_puts_memcg_tunable(m, |
6482 | READ_ONCE(mem_cgroup_from_seq(m)->memory.high)); | |
241994ed JW |
6483 | } |
6484 | ||
6485 | static ssize_t memory_high_write(struct kernfs_open_file *of, | |
6486 | char *buf, size_t nbytes, loff_t off) | |
6487 | { | |
6488 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
d977aa93 | 6489 | unsigned int nr_retries = MAX_RECLAIM_RETRIES; |
8c8c383c | 6490 | bool drained = false; |
241994ed JW |
6491 | unsigned long high; |
6492 | int err; | |
6493 | ||
6494 | buf = strstrip(buf); | |
d2973697 | 6495 | err = page_counter_memparse(buf, "max", &high); |
241994ed JW |
6496 | if (err) |
6497 | return err; | |
6498 | ||
e82553c1 JW |
6499 | page_counter_set_high(&memcg->memory, high); |
6500 | ||
8c8c383c JW |
6501 | for (;;) { |
6502 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
6503 | unsigned long reclaimed; | |
6504 | ||
6505 | if (nr_pages <= high) | |
6506 | break; | |
6507 | ||
6508 | if (signal_pending(current)) | |
6509 | break; | |
6510 | ||
6511 | if (!drained) { | |
6512 | drain_all_stock(memcg); | |
6513 | drained = true; | |
6514 | continue; | |
6515 | } | |
6516 | ||
6517 | reclaimed = try_to_free_mem_cgroup_pages(memcg, nr_pages - high, | |
55ab834a | 6518 | GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP); |
8c8c383c JW |
6519 | |
6520 | if (!reclaimed && !nr_retries--) | |
6521 | break; | |
6522 | } | |
588083bb | 6523 | |
19ce33ac | 6524 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
6525 | return nbytes; |
6526 | } | |
6527 | ||
6528 | static int memory_max_show(struct seq_file *m, void *v) | |
6529 | { | |
677dc973 CD |
6530 | return seq_puts_memcg_tunable(m, |
6531 | READ_ONCE(mem_cgroup_from_seq(m)->memory.max)); | |
241994ed JW |
6532 | } |
6533 | ||
6534 | static ssize_t memory_max_write(struct kernfs_open_file *of, | |
6535 | char *buf, size_t nbytes, loff_t off) | |
6536 | { | |
6537 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
d977aa93 | 6538 | unsigned int nr_reclaims = MAX_RECLAIM_RETRIES; |
b6e6edcf | 6539 | bool drained = false; |
241994ed JW |
6540 | unsigned long max; |
6541 | int err; | |
6542 | ||
6543 | buf = strstrip(buf); | |
d2973697 | 6544 | err = page_counter_memparse(buf, "max", &max); |
241994ed JW |
6545 | if (err) |
6546 | return err; | |
6547 | ||
bbec2e15 | 6548 | xchg(&memcg->memory.max, max); |
b6e6edcf JW |
6549 | |
6550 | for (;;) { | |
6551 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
6552 | ||
6553 | if (nr_pages <= max) | |
6554 | break; | |
6555 | ||
7249c9f0 | 6556 | if (signal_pending(current)) |
b6e6edcf | 6557 | break; |
b6e6edcf JW |
6558 | |
6559 | if (!drained) { | |
6560 | drain_all_stock(memcg); | |
6561 | drained = true; | |
6562 | continue; | |
6563 | } | |
6564 | ||
6565 | if (nr_reclaims) { | |
6566 | if (!try_to_free_mem_cgroup_pages(memcg, nr_pages - max, | |
55ab834a | 6567 | GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP)) |
b6e6edcf JW |
6568 | nr_reclaims--; |
6569 | continue; | |
6570 | } | |
6571 | ||
e27be240 | 6572 | memcg_memory_event(memcg, MEMCG_OOM); |
b6e6edcf JW |
6573 | if (!mem_cgroup_out_of_memory(memcg, GFP_KERNEL, 0)) |
6574 | break; | |
6575 | } | |
241994ed | 6576 | |
2529bb3a | 6577 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
6578 | return nbytes; |
6579 | } | |
6580 | ||
1e577f97 SB |
6581 | static void __memory_events_show(struct seq_file *m, atomic_long_t *events) |
6582 | { | |
6583 | seq_printf(m, "low %lu\n", atomic_long_read(&events[MEMCG_LOW])); | |
6584 | seq_printf(m, "high %lu\n", atomic_long_read(&events[MEMCG_HIGH])); | |
6585 | seq_printf(m, "max %lu\n", atomic_long_read(&events[MEMCG_MAX])); | |
6586 | seq_printf(m, "oom %lu\n", atomic_long_read(&events[MEMCG_OOM])); | |
6587 | seq_printf(m, "oom_kill %lu\n", | |
6588 | atomic_long_read(&events[MEMCG_OOM_KILL])); | |
b6bf9abb DS |
6589 | seq_printf(m, "oom_group_kill %lu\n", |
6590 | atomic_long_read(&events[MEMCG_OOM_GROUP_KILL])); | |
1e577f97 SB |
6591 | } |
6592 | ||
241994ed JW |
6593 | static int memory_events_show(struct seq_file *m, void *v) |
6594 | { | |
aa9694bb | 6595 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
241994ed | 6596 | |
1e577f97 SB |
6597 | __memory_events_show(m, memcg->memory_events); |
6598 | return 0; | |
6599 | } | |
6600 | ||
6601 | static int memory_events_local_show(struct seq_file *m, void *v) | |
6602 | { | |
6603 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); | |
241994ed | 6604 | |
1e577f97 | 6605 | __memory_events_show(m, memcg->memory_events_local); |
241994ed JW |
6606 | return 0; |
6607 | } | |
6608 | ||
587d9f72 JW |
6609 | static int memory_stat_show(struct seq_file *m, void *v) |
6610 | { | |
aa9694bb | 6611 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
68aaee14 | 6612 | char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL); |
5b42360c | 6613 | struct seq_buf s; |
1ff9e6e1 | 6614 | |
c8713d0b JW |
6615 | if (!buf) |
6616 | return -ENOMEM; | |
5b42360c YA |
6617 | seq_buf_init(&s, buf, PAGE_SIZE); |
6618 | memory_stat_format(memcg, &s); | |
c8713d0b JW |
6619 | seq_puts(m, buf); |
6620 | kfree(buf); | |
587d9f72 JW |
6621 | return 0; |
6622 | } | |
6623 | ||
5f9a4f4a | 6624 | #ifdef CONFIG_NUMA |
fff66b79 MS |
6625 | static inline unsigned long lruvec_page_state_output(struct lruvec *lruvec, |
6626 | int item) | |
6627 | { | |
6628 | return lruvec_page_state(lruvec, item) * memcg_page_state_unit(item); | |
6629 | } | |
6630 | ||
5f9a4f4a MS |
6631 | static int memory_numa_stat_show(struct seq_file *m, void *v) |
6632 | { | |
6633 | int i; | |
6634 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); | |
6635 | ||
fd25a9e0 | 6636 | mem_cgroup_flush_stats(); |
7e1c0d6f | 6637 | |
5f9a4f4a MS |
6638 | for (i = 0; i < ARRAY_SIZE(memory_stats); i++) { |
6639 | int nid; | |
6640 | ||
6641 | if (memory_stats[i].idx >= NR_VM_NODE_STAT_ITEMS) | |
6642 | continue; | |
6643 | ||
6644 | seq_printf(m, "%s", memory_stats[i].name); | |
6645 | for_each_node_state(nid, N_MEMORY) { | |
6646 | u64 size; | |
6647 | struct lruvec *lruvec; | |
6648 | ||
6649 | lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); | |
fff66b79 MS |
6650 | size = lruvec_page_state_output(lruvec, |
6651 | memory_stats[i].idx); | |
5f9a4f4a MS |
6652 | seq_printf(m, " N%d=%llu", nid, size); |
6653 | } | |
6654 | seq_putc(m, '\n'); | |
6655 | } | |
6656 | ||
6657 | return 0; | |
6658 | } | |
6659 | #endif | |
6660 | ||
3d8b38eb RG |
6661 | static int memory_oom_group_show(struct seq_file *m, void *v) |
6662 | { | |
aa9694bb | 6663 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
3d8b38eb | 6664 | |
eaf7b66b | 6665 | seq_printf(m, "%d\n", READ_ONCE(memcg->oom_group)); |
3d8b38eb RG |
6666 | |
6667 | return 0; | |
6668 | } | |
6669 | ||
6670 | static ssize_t memory_oom_group_write(struct kernfs_open_file *of, | |
6671 | char *buf, size_t nbytes, loff_t off) | |
6672 | { | |
6673 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6674 | int ret, oom_group; | |
6675 | ||
6676 | buf = strstrip(buf); | |
6677 | if (!buf) | |
6678 | return -EINVAL; | |
6679 | ||
6680 | ret = kstrtoint(buf, 0, &oom_group); | |
6681 | if (ret) | |
6682 | return ret; | |
6683 | ||
6684 | if (oom_group != 0 && oom_group != 1) | |
6685 | return -EINVAL; | |
6686 | ||
eaf7b66b | 6687 | WRITE_ONCE(memcg->oom_group, oom_group); |
3d8b38eb RG |
6688 | |
6689 | return nbytes; | |
6690 | } | |
6691 | ||
94968384 SB |
6692 | static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf, |
6693 | size_t nbytes, loff_t off) | |
6694 | { | |
6695 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6696 | unsigned int nr_retries = MAX_RECLAIM_RETRIES; | |
6697 | unsigned long nr_to_reclaim, nr_reclaimed = 0; | |
55ab834a MH |
6698 | unsigned int reclaim_options; |
6699 | int err; | |
12a5d395 MA |
6700 | |
6701 | buf = strstrip(buf); | |
55ab834a MH |
6702 | err = page_counter_memparse(buf, "", &nr_to_reclaim); |
6703 | if (err) | |
6704 | return err; | |
12a5d395 | 6705 | |
55ab834a | 6706 | reclaim_options = MEMCG_RECLAIM_MAY_SWAP | MEMCG_RECLAIM_PROACTIVE; |
94968384 SB |
6707 | while (nr_reclaimed < nr_to_reclaim) { |
6708 | unsigned long reclaimed; | |
6709 | ||
6710 | if (signal_pending(current)) | |
6711 | return -EINTR; | |
6712 | ||
6713 | /* | |
6714 | * This is the final attempt, drain percpu lru caches in the | |
6715 | * hope of introducing more evictable pages for | |
6716 | * try_to_free_mem_cgroup_pages(). | |
6717 | */ | |
6718 | if (!nr_retries) | |
6719 | lru_add_drain_all(); | |
6720 | ||
6721 | reclaimed = try_to_free_mem_cgroup_pages(memcg, | |
0388536a EY |
6722 | min(nr_to_reclaim - nr_reclaimed, SWAP_CLUSTER_MAX), |
6723 | GFP_KERNEL, reclaim_options); | |
94968384 SB |
6724 | |
6725 | if (!reclaimed && !nr_retries--) | |
6726 | return -EAGAIN; | |
6727 | ||
6728 | nr_reclaimed += reclaimed; | |
6729 | } | |
6730 | ||
6731 | return nbytes; | |
6732 | } | |
6733 | ||
241994ed JW |
6734 | static struct cftype memory_files[] = { |
6735 | { | |
6736 | .name = "current", | |
f5fc3c5d | 6737 | .flags = CFTYPE_NOT_ON_ROOT, |
241994ed JW |
6738 | .read_u64 = memory_current_read, |
6739 | }, | |
8e20d4b3 GR |
6740 | { |
6741 | .name = "peak", | |
6742 | .flags = CFTYPE_NOT_ON_ROOT, | |
6743 | .read_u64 = memory_peak_read, | |
6744 | }, | |
bf8d5d52 RG |
6745 | { |
6746 | .name = "min", | |
6747 | .flags = CFTYPE_NOT_ON_ROOT, | |
6748 | .seq_show = memory_min_show, | |
6749 | .write = memory_min_write, | |
6750 | }, | |
241994ed JW |
6751 | { |
6752 | .name = "low", | |
6753 | .flags = CFTYPE_NOT_ON_ROOT, | |
6754 | .seq_show = memory_low_show, | |
6755 | .write = memory_low_write, | |
6756 | }, | |
6757 | { | |
6758 | .name = "high", | |
6759 | .flags = CFTYPE_NOT_ON_ROOT, | |
6760 | .seq_show = memory_high_show, | |
6761 | .write = memory_high_write, | |
6762 | }, | |
6763 | { | |
6764 | .name = "max", | |
6765 | .flags = CFTYPE_NOT_ON_ROOT, | |
6766 | .seq_show = memory_max_show, | |
6767 | .write = memory_max_write, | |
6768 | }, | |
6769 | { | |
6770 | .name = "events", | |
6771 | .flags = CFTYPE_NOT_ON_ROOT, | |
472912a2 | 6772 | .file_offset = offsetof(struct mem_cgroup, events_file), |
241994ed JW |
6773 | .seq_show = memory_events_show, |
6774 | }, | |
1e577f97 SB |
6775 | { |
6776 | .name = "events.local", | |
6777 | .flags = CFTYPE_NOT_ON_ROOT, | |
6778 | .file_offset = offsetof(struct mem_cgroup, events_local_file), | |
6779 | .seq_show = memory_events_local_show, | |
6780 | }, | |
587d9f72 JW |
6781 | { |
6782 | .name = "stat", | |
587d9f72 JW |
6783 | .seq_show = memory_stat_show, |
6784 | }, | |
5f9a4f4a MS |
6785 | #ifdef CONFIG_NUMA |
6786 | { | |
6787 | .name = "numa_stat", | |
6788 | .seq_show = memory_numa_stat_show, | |
6789 | }, | |
6790 | #endif | |
3d8b38eb RG |
6791 | { |
6792 | .name = "oom.group", | |
6793 | .flags = CFTYPE_NOT_ON_ROOT | CFTYPE_NS_DELEGATABLE, | |
6794 | .seq_show = memory_oom_group_show, | |
6795 | .write = memory_oom_group_write, | |
6796 | }, | |
94968384 SB |
6797 | { |
6798 | .name = "reclaim", | |
6799 | .flags = CFTYPE_NS_DELEGATABLE, | |
6800 | .write = memory_reclaim, | |
6801 | }, | |
241994ed JW |
6802 | { } /* terminate */ |
6803 | }; | |
6804 | ||
073219e9 | 6805 | struct cgroup_subsys memory_cgrp_subsys = { |
92fb9748 | 6806 | .css_alloc = mem_cgroup_css_alloc, |
d142e3e6 | 6807 | .css_online = mem_cgroup_css_online, |
92fb9748 | 6808 | .css_offline = mem_cgroup_css_offline, |
6df38689 | 6809 | .css_released = mem_cgroup_css_released, |
92fb9748 | 6810 | .css_free = mem_cgroup_css_free, |
1ced953b | 6811 | .css_reset = mem_cgroup_css_reset, |
2d146aa3 | 6812 | .css_rstat_flush = mem_cgroup_css_rstat_flush, |
7dc74be0 | 6813 | .can_attach = mem_cgroup_can_attach, |
bd74fdae | 6814 | .attach = mem_cgroup_attach, |
7dc74be0 | 6815 | .cancel_attach = mem_cgroup_cancel_attach, |
264a0ae1 | 6816 | .post_attach = mem_cgroup_move_task, |
241994ed JW |
6817 | .dfl_cftypes = memory_files, |
6818 | .legacy_cftypes = mem_cgroup_legacy_files, | |
6d12e2d8 | 6819 | .early_init = 0, |
8cdea7c0 | 6820 | }; |
c077719b | 6821 | |
bc50bcc6 JW |
6822 | /* |
6823 | * This function calculates an individual cgroup's effective | |
6824 | * protection which is derived from its own memory.min/low, its | |
6825 | * parent's and siblings' settings, as well as the actual memory | |
6826 | * distribution in the tree. | |
6827 | * | |
6828 | * The following rules apply to the effective protection values: | |
6829 | * | |
6830 | * 1. At the first level of reclaim, effective protection is equal to | |
6831 | * the declared protection in memory.min and memory.low. | |
6832 | * | |
6833 | * 2. To enable safe delegation of the protection configuration, at | |
6834 | * subsequent levels the effective protection is capped to the | |
6835 | * parent's effective protection. | |
6836 | * | |
6837 | * 3. To make complex and dynamic subtrees easier to configure, the | |
6838 | * user is allowed to overcommit the declared protection at a given | |
6839 | * level. If that is the case, the parent's effective protection is | |
6840 | * distributed to the children in proportion to how much protection | |
6841 | * they have declared and how much of it they are utilizing. | |
6842 | * | |
6843 | * This makes distribution proportional, but also work-conserving: | |
6844 | * if one cgroup claims much more protection than it uses memory, | |
6845 | * the unused remainder is available to its siblings. | |
6846 | * | |
6847 | * 4. Conversely, when the declared protection is undercommitted at a | |
6848 | * given level, the distribution of the larger parental protection | |
6849 | * budget is NOT proportional. A cgroup's protection from a sibling | |
6850 | * is capped to its own memory.min/low setting. | |
6851 | * | |
8a931f80 JW |
6852 | * 5. However, to allow protecting recursive subtrees from each other |
6853 | * without having to declare each individual cgroup's fixed share | |
6854 | * of the ancestor's claim to protection, any unutilized - | |
6855 | * "floating" - protection from up the tree is distributed in | |
6856 | * proportion to each cgroup's *usage*. This makes the protection | |
6857 | * neutral wrt sibling cgroups and lets them compete freely over | |
6858 | * the shared parental protection budget, but it protects the | |
6859 | * subtree as a whole from neighboring subtrees. | |
6860 | * | |
6861 | * Note that 4. and 5. are not in conflict: 4. is about protecting | |
6862 | * against immediate siblings whereas 5. is about protecting against | |
6863 | * neighboring subtrees. | |
bc50bcc6 JW |
6864 | */ |
6865 | static unsigned long effective_protection(unsigned long usage, | |
8a931f80 | 6866 | unsigned long parent_usage, |
bc50bcc6 JW |
6867 | unsigned long setting, |
6868 | unsigned long parent_effective, | |
6869 | unsigned long siblings_protected) | |
6870 | { | |
6871 | unsigned long protected; | |
8a931f80 | 6872 | unsigned long ep; |
bc50bcc6 JW |
6873 | |
6874 | protected = min(usage, setting); | |
6875 | /* | |
6876 | * If all cgroups at this level combined claim and use more | |
08e0f49e | 6877 | * protection than what the parent affords them, distribute |
bc50bcc6 JW |
6878 | * shares in proportion to utilization. |
6879 | * | |
6880 | * We are using actual utilization rather than the statically | |
6881 | * claimed protection in order to be work-conserving: claimed | |
6882 | * but unused protection is available to siblings that would | |
6883 | * otherwise get a smaller chunk than what they claimed. | |
6884 | */ | |
6885 | if (siblings_protected > parent_effective) | |
6886 | return protected * parent_effective / siblings_protected; | |
6887 | ||
6888 | /* | |
6889 | * Ok, utilized protection of all children is within what the | |
6890 | * parent affords them, so we know whatever this child claims | |
6891 | * and utilizes is effectively protected. | |
6892 | * | |
6893 | * If there is unprotected usage beyond this value, reclaim | |
6894 | * will apply pressure in proportion to that amount. | |
6895 | * | |
6896 | * If there is unutilized protection, the cgroup will be fully | |
6897 | * shielded from reclaim, but we do return a smaller value for | |
6898 | * protection than what the group could enjoy in theory. This | |
6899 | * is okay. With the overcommit distribution above, effective | |
6900 | * protection is always dependent on how memory is actually | |
6901 | * consumed among the siblings anyway. | |
6902 | */ | |
8a931f80 JW |
6903 | ep = protected; |
6904 | ||
6905 | /* | |
6906 | * If the children aren't claiming (all of) the protection | |
6907 | * afforded to them by the parent, distribute the remainder in | |
6908 | * proportion to the (unprotected) memory of each cgroup. That | |
6909 | * way, cgroups that aren't explicitly prioritized wrt each | |
6910 | * other compete freely over the allowance, but they are | |
6911 | * collectively protected from neighboring trees. | |
6912 | * | |
6913 | * We're using unprotected memory for the weight so that if | |
6914 | * some cgroups DO claim explicit protection, we don't protect | |
6915 | * the same bytes twice. | |
cd324edc JW |
6916 | * |
6917 | * Check both usage and parent_usage against the respective | |
6918 | * protected values. One should imply the other, but they | |
6919 | * aren't read atomically - make sure the division is sane. | |
8a931f80 JW |
6920 | */ |
6921 | if (!(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_RECURSIVE_PROT)) | |
6922 | return ep; | |
cd324edc JW |
6923 | if (parent_effective > siblings_protected && |
6924 | parent_usage > siblings_protected && | |
6925 | usage > protected) { | |
8a931f80 JW |
6926 | unsigned long unclaimed; |
6927 | ||
6928 | unclaimed = parent_effective - siblings_protected; | |
6929 | unclaimed *= usage - protected; | |
6930 | unclaimed /= parent_usage - siblings_protected; | |
6931 | ||
6932 | ep += unclaimed; | |
6933 | } | |
6934 | ||
6935 | return ep; | |
bc50bcc6 JW |
6936 | } |
6937 | ||
241994ed | 6938 | /** |
05395718 | 6939 | * mem_cgroup_calculate_protection - check if memory consumption is in the normal range |
34c81057 | 6940 | * @root: the top ancestor of the sub-tree being checked |
241994ed JW |
6941 | * @memcg: the memory cgroup to check |
6942 | * | |
23067153 RG |
6943 | * WARNING: This function is not stateless! It can only be used as part |
6944 | * of a top-down tree iteration, not for isolated queries. | |
241994ed | 6945 | */ |
45c7f7e1 CD |
6946 | void mem_cgroup_calculate_protection(struct mem_cgroup *root, |
6947 | struct mem_cgroup *memcg) | |
241994ed | 6948 | { |
8a931f80 | 6949 | unsigned long usage, parent_usage; |
23067153 RG |
6950 | struct mem_cgroup *parent; |
6951 | ||
241994ed | 6952 | if (mem_cgroup_disabled()) |
45c7f7e1 | 6953 | return; |
241994ed | 6954 | |
34c81057 SC |
6955 | if (!root) |
6956 | root = root_mem_cgroup; | |
22f7496f YS |
6957 | |
6958 | /* | |
6959 | * Effective values of the reclaim targets are ignored so they | |
6960 | * can be stale. Have a look at mem_cgroup_protection for more | |
6961 | * details. | |
6962 | * TODO: calculation should be more robust so that we do not need | |
6963 | * that special casing. | |
6964 | */ | |
34c81057 | 6965 | if (memcg == root) |
45c7f7e1 | 6966 | return; |
241994ed | 6967 | |
23067153 | 6968 | usage = page_counter_read(&memcg->memory); |
bf8d5d52 | 6969 | if (!usage) |
45c7f7e1 | 6970 | return; |
bf8d5d52 | 6971 | |
bf8d5d52 | 6972 | parent = parent_mem_cgroup(memcg); |
df2a4196 | 6973 | |
bc50bcc6 | 6974 | if (parent == root) { |
c3d53200 | 6975 | memcg->memory.emin = READ_ONCE(memcg->memory.min); |
03960e33 | 6976 | memcg->memory.elow = READ_ONCE(memcg->memory.low); |
45c7f7e1 | 6977 | return; |
bf8d5d52 RG |
6978 | } |
6979 | ||
8a931f80 JW |
6980 | parent_usage = page_counter_read(&parent->memory); |
6981 | ||
b3a7822e | 6982 | WRITE_ONCE(memcg->memory.emin, effective_protection(usage, parent_usage, |
c3d53200 CD |
6983 | READ_ONCE(memcg->memory.min), |
6984 | READ_ONCE(parent->memory.emin), | |
b3a7822e | 6985 | atomic_long_read(&parent->memory.children_min_usage))); |
23067153 | 6986 | |
b3a7822e | 6987 | WRITE_ONCE(memcg->memory.elow, effective_protection(usage, parent_usage, |
03960e33 CD |
6988 | READ_ONCE(memcg->memory.low), |
6989 | READ_ONCE(parent->memory.elow), | |
b3a7822e | 6990 | atomic_long_read(&parent->memory.children_low_usage))); |
241994ed JW |
6991 | } |
6992 | ||
8f425e4e MWO |
6993 | static int charge_memcg(struct folio *folio, struct mem_cgroup *memcg, |
6994 | gfp_t gfp) | |
0add0c77 | 6995 | { |
118f2875 | 6996 | long nr_pages = folio_nr_pages(folio); |
0add0c77 SB |
6997 | int ret; |
6998 | ||
6999 | ret = try_charge(memcg, gfp, nr_pages); | |
7000 | if (ret) | |
7001 | goto out; | |
7002 | ||
7003 | css_get(&memcg->css); | |
118f2875 | 7004 | commit_charge(folio, memcg); |
0add0c77 SB |
7005 | |
7006 | local_irq_disable(); | |
6e0110c2 | 7007 | mem_cgroup_charge_statistics(memcg, nr_pages); |
8f425e4e | 7008 | memcg_check_events(memcg, folio_nid(folio)); |
0add0c77 SB |
7009 | local_irq_enable(); |
7010 | out: | |
7011 | return ret; | |
7012 | } | |
7013 | ||
8f425e4e | 7014 | int __mem_cgroup_charge(struct folio *folio, struct mm_struct *mm, gfp_t gfp) |
00501b53 | 7015 | { |
0add0c77 SB |
7016 | struct mem_cgroup *memcg; |
7017 | int ret; | |
00501b53 | 7018 | |
0add0c77 | 7019 | memcg = get_mem_cgroup_from_mm(mm); |
8f425e4e | 7020 | ret = charge_memcg(folio, memcg, gfp); |
0add0c77 | 7021 | css_put(&memcg->css); |
2d1c4980 | 7022 | |
0add0c77 SB |
7023 | return ret; |
7024 | } | |
e993d905 | 7025 | |
0add0c77 | 7026 | /** |
65995918 MWO |
7027 | * mem_cgroup_swapin_charge_folio - Charge a newly allocated folio for swapin. |
7028 | * @folio: folio to charge. | |
0add0c77 SB |
7029 | * @mm: mm context of the victim |
7030 | * @gfp: reclaim mode | |
65995918 | 7031 | * @entry: swap entry for which the folio is allocated |
0add0c77 | 7032 | * |
65995918 MWO |
7033 | * This function charges a folio allocated for swapin. Please call this before |
7034 | * adding the folio to the swapcache. | |
0add0c77 SB |
7035 | * |
7036 | * Returns 0 on success. Otherwise, an error code is returned. | |
7037 | */ | |
65995918 | 7038 | int mem_cgroup_swapin_charge_folio(struct folio *folio, struct mm_struct *mm, |
0add0c77 SB |
7039 | gfp_t gfp, swp_entry_t entry) |
7040 | { | |
7041 | struct mem_cgroup *memcg; | |
7042 | unsigned short id; | |
7043 | int ret; | |
00501b53 | 7044 | |
0add0c77 SB |
7045 | if (mem_cgroup_disabled()) |
7046 | return 0; | |
00501b53 | 7047 | |
0add0c77 SB |
7048 | id = lookup_swap_cgroup_id(entry); |
7049 | rcu_read_lock(); | |
7050 | memcg = mem_cgroup_from_id(id); | |
7051 | if (!memcg || !css_tryget_online(&memcg->css)) | |
7052 | memcg = get_mem_cgroup_from_mm(mm); | |
7053 | rcu_read_unlock(); | |
00501b53 | 7054 | |
8f425e4e | 7055 | ret = charge_memcg(folio, memcg, gfp); |
6abb5a86 | 7056 | |
0add0c77 SB |
7057 | css_put(&memcg->css); |
7058 | return ret; | |
7059 | } | |
00501b53 | 7060 | |
0add0c77 SB |
7061 | /* |
7062 | * mem_cgroup_swapin_uncharge_swap - uncharge swap slot | |
7063 | * @entry: swap entry for which the page is charged | |
7064 | * | |
7065 | * Call this function after successfully adding the charged page to swapcache. | |
7066 | * | |
7067 | * Note: This function assumes the page for which swap slot is being uncharged | |
7068 | * is order 0 page. | |
7069 | */ | |
7070 | void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry) | |
7071 | { | |
cae3af62 MS |
7072 | /* |
7073 | * Cgroup1's unified memory+swap counter has been charged with the | |
7074 | * new swapcache page, finish the transfer by uncharging the swap | |
7075 | * slot. The swap slot would also get uncharged when it dies, but | |
7076 | * it can stick around indefinitely and we'd count the page twice | |
7077 | * the entire time. | |
7078 | * | |
7079 | * Cgroup2 has separate resource counters for memory and swap, | |
7080 | * so this is a non-issue here. Memory and swap charge lifetimes | |
7081 | * correspond 1:1 to page and swap slot lifetimes: we charge the | |
7082 | * page to memory here, and uncharge swap when the slot is freed. | |
7083 | */ | |
0add0c77 | 7084 | if (!mem_cgroup_disabled() && do_memsw_account()) { |
00501b53 JW |
7085 | /* |
7086 | * The swap entry might not get freed for a long time, | |
7087 | * let's not wait for it. The page already received a | |
7088 | * memory+swap charge, drop the swap entry duplicate. | |
7089 | */ | |
0add0c77 | 7090 | mem_cgroup_uncharge_swap(entry, 1); |
00501b53 | 7091 | } |
3fea5a49 JW |
7092 | } |
7093 | ||
a9d5adee JG |
7094 | struct uncharge_gather { |
7095 | struct mem_cgroup *memcg; | |
b4e0b68f | 7096 | unsigned long nr_memory; |
a9d5adee | 7097 | unsigned long pgpgout; |
a9d5adee | 7098 | unsigned long nr_kmem; |
8e88bd2d | 7099 | int nid; |
a9d5adee JG |
7100 | }; |
7101 | ||
7102 | static inline void uncharge_gather_clear(struct uncharge_gather *ug) | |
747db954 | 7103 | { |
a9d5adee JG |
7104 | memset(ug, 0, sizeof(*ug)); |
7105 | } | |
7106 | ||
7107 | static void uncharge_batch(const struct uncharge_gather *ug) | |
7108 | { | |
747db954 JW |
7109 | unsigned long flags; |
7110 | ||
b4e0b68f MS |
7111 | if (ug->nr_memory) { |
7112 | page_counter_uncharge(&ug->memcg->memory, ug->nr_memory); | |
7941d214 | 7113 | if (do_memsw_account()) |
b4e0b68f | 7114 | page_counter_uncharge(&ug->memcg->memsw, ug->nr_memory); |
a8c49af3 YA |
7115 | if (ug->nr_kmem) |
7116 | memcg_account_kmem(ug->memcg, -ug->nr_kmem); | |
a9d5adee | 7117 | memcg_oom_recover(ug->memcg); |
ce00a967 | 7118 | } |
747db954 JW |
7119 | |
7120 | local_irq_save(flags); | |
c9019e9b | 7121 | __count_memcg_events(ug->memcg, PGPGOUT, ug->pgpgout); |
b4e0b68f | 7122 | __this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, ug->nr_memory); |
8e88bd2d | 7123 | memcg_check_events(ug->memcg, ug->nid); |
747db954 | 7124 | local_irq_restore(flags); |
f1796544 | 7125 | |
c4ed6ebf | 7126 | /* drop reference from uncharge_folio */ |
f1796544 | 7127 | css_put(&ug->memcg->css); |
a9d5adee JG |
7128 | } |
7129 | ||
c4ed6ebf | 7130 | static void uncharge_folio(struct folio *folio, struct uncharge_gather *ug) |
a9d5adee | 7131 | { |
c4ed6ebf | 7132 | long nr_pages; |
b4e0b68f MS |
7133 | struct mem_cgroup *memcg; |
7134 | struct obj_cgroup *objcg; | |
9f762dbe | 7135 | |
c4ed6ebf | 7136 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
a9d5adee | 7137 | |
a9d5adee JG |
7138 | /* |
7139 | * Nobody should be changing or seriously looking at | |
c4ed6ebf MWO |
7140 | * folio memcg or objcg at this point, we have fully |
7141 | * exclusive access to the folio. | |
a9d5adee | 7142 | */ |
fead2b86 | 7143 | if (folio_memcg_kmem(folio)) { |
1b7e4464 | 7144 | objcg = __folio_objcg(folio); |
b4e0b68f MS |
7145 | /* |
7146 | * This get matches the put at the end of the function and | |
7147 | * kmem pages do not hold memcg references anymore. | |
7148 | */ | |
7149 | memcg = get_mem_cgroup_from_objcg(objcg); | |
7150 | } else { | |
1b7e4464 | 7151 | memcg = __folio_memcg(folio); |
b4e0b68f | 7152 | } |
a9d5adee | 7153 | |
b4e0b68f MS |
7154 | if (!memcg) |
7155 | return; | |
7156 | ||
7157 | if (ug->memcg != memcg) { | |
a9d5adee JG |
7158 | if (ug->memcg) { |
7159 | uncharge_batch(ug); | |
7160 | uncharge_gather_clear(ug); | |
7161 | } | |
b4e0b68f | 7162 | ug->memcg = memcg; |
c4ed6ebf | 7163 | ug->nid = folio_nid(folio); |
f1796544 MH |
7164 | |
7165 | /* pairs with css_put in uncharge_batch */ | |
b4e0b68f | 7166 | css_get(&memcg->css); |
a9d5adee JG |
7167 | } |
7168 | ||
c4ed6ebf | 7169 | nr_pages = folio_nr_pages(folio); |
a9d5adee | 7170 | |
fead2b86 | 7171 | if (folio_memcg_kmem(folio)) { |
b4e0b68f | 7172 | ug->nr_memory += nr_pages; |
9f762dbe | 7173 | ug->nr_kmem += nr_pages; |
b4e0b68f | 7174 | |
c4ed6ebf | 7175 | folio->memcg_data = 0; |
b4e0b68f MS |
7176 | obj_cgroup_put(objcg); |
7177 | } else { | |
7178 | /* LRU pages aren't accounted at the root level */ | |
7179 | if (!mem_cgroup_is_root(memcg)) | |
7180 | ug->nr_memory += nr_pages; | |
18b2db3b | 7181 | ug->pgpgout++; |
a9d5adee | 7182 | |
c4ed6ebf | 7183 | folio->memcg_data = 0; |
b4e0b68f MS |
7184 | } |
7185 | ||
7186 | css_put(&memcg->css); | |
747db954 JW |
7187 | } |
7188 | ||
bbc6b703 | 7189 | void __mem_cgroup_uncharge(struct folio *folio) |
0a31bc97 | 7190 | { |
a9d5adee JG |
7191 | struct uncharge_gather ug; |
7192 | ||
bbc6b703 MWO |
7193 | /* Don't touch folio->lru of any random page, pre-check: */ |
7194 | if (!folio_memcg(folio)) | |
0a31bc97 JW |
7195 | return; |
7196 | ||
a9d5adee | 7197 | uncharge_gather_clear(&ug); |
bbc6b703 | 7198 | uncharge_folio(folio, &ug); |
a9d5adee | 7199 | uncharge_batch(&ug); |
747db954 | 7200 | } |
0a31bc97 | 7201 | |
747db954 | 7202 | /** |
2c8d8f97 | 7203 | * __mem_cgroup_uncharge_list - uncharge a list of page |
747db954 JW |
7204 | * @page_list: list of pages to uncharge |
7205 | * | |
7206 | * Uncharge a list of pages previously charged with | |
2c8d8f97 | 7207 | * __mem_cgroup_charge(). |
747db954 | 7208 | */ |
2c8d8f97 | 7209 | void __mem_cgroup_uncharge_list(struct list_head *page_list) |
747db954 | 7210 | { |
c41a40b6 | 7211 | struct uncharge_gather ug; |
c4ed6ebf | 7212 | struct folio *folio; |
c41a40b6 | 7213 | |
c41a40b6 | 7214 | uncharge_gather_clear(&ug); |
c4ed6ebf MWO |
7215 | list_for_each_entry(folio, page_list, lru) |
7216 | uncharge_folio(folio, &ug); | |
c41a40b6 MS |
7217 | if (ug.memcg) |
7218 | uncharge_batch(&ug); | |
0a31bc97 JW |
7219 | } |
7220 | ||
7221 | /** | |
d21bba2b MWO |
7222 | * mem_cgroup_migrate - Charge a folio's replacement. |
7223 | * @old: Currently circulating folio. | |
7224 | * @new: Replacement folio. | |
0a31bc97 | 7225 | * |
d21bba2b | 7226 | * Charge @new as a replacement folio for @old. @old will |
6a93ca8f | 7227 | * be uncharged upon free. |
0a31bc97 | 7228 | * |
d21bba2b | 7229 | * Both folios must be locked, @new->mapping must be set up. |
0a31bc97 | 7230 | */ |
d21bba2b | 7231 | void mem_cgroup_migrate(struct folio *old, struct folio *new) |
0a31bc97 | 7232 | { |
29833315 | 7233 | struct mem_cgroup *memcg; |
d21bba2b | 7234 | long nr_pages = folio_nr_pages(new); |
d93c4130 | 7235 | unsigned long flags; |
0a31bc97 | 7236 | |
d21bba2b MWO |
7237 | VM_BUG_ON_FOLIO(!folio_test_locked(old), old); |
7238 | VM_BUG_ON_FOLIO(!folio_test_locked(new), new); | |
7239 | VM_BUG_ON_FOLIO(folio_test_anon(old) != folio_test_anon(new), new); | |
7240 | VM_BUG_ON_FOLIO(folio_nr_pages(old) != nr_pages, new); | |
0a31bc97 JW |
7241 | |
7242 | if (mem_cgroup_disabled()) | |
7243 | return; | |
7244 | ||
d21bba2b MWO |
7245 | /* Page cache replacement: new folio already charged? */ |
7246 | if (folio_memcg(new)) | |
0a31bc97 JW |
7247 | return; |
7248 | ||
d21bba2b MWO |
7249 | memcg = folio_memcg(old); |
7250 | VM_WARN_ON_ONCE_FOLIO(!memcg, old); | |
29833315 | 7251 | if (!memcg) |
0a31bc97 JW |
7252 | return; |
7253 | ||
44b7a8d3 | 7254 | /* Force-charge the new page. The old one will be freed soon */ |
8dc87c7d MS |
7255 | if (!mem_cgroup_is_root(memcg)) { |
7256 | page_counter_charge(&memcg->memory, nr_pages); | |
7257 | if (do_memsw_account()) | |
7258 | page_counter_charge(&memcg->memsw, nr_pages); | |
7259 | } | |
0a31bc97 | 7260 | |
1a3e1f40 | 7261 | css_get(&memcg->css); |
d21bba2b | 7262 | commit_charge(new, memcg); |
44b7a8d3 | 7263 | |
d93c4130 | 7264 | local_irq_save(flags); |
6e0110c2 | 7265 | mem_cgroup_charge_statistics(memcg, nr_pages); |
d21bba2b | 7266 | memcg_check_events(memcg, folio_nid(new)); |
d93c4130 | 7267 | local_irq_restore(flags); |
0a31bc97 JW |
7268 | } |
7269 | ||
ef12947c | 7270 | DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key); |
11092087 JW |
7271 | EXPORT_SYMBOL(memcg_sockets_enabled_key); |
7272 | ||
2d758073 | 7273 | void mem_cgroup_sk_alloc(struct sock *sk) |
11092087 JW |
7274 | { |
7275 | struct mem_cgroup *memcg; | |
7276 | ||
2d758073 JW |
7277 | if (!mem_cgroup_sockets_enabled) |
7278 | return; | |
7279 | ||
e876ecc6 | 7280 | /* Do not associate the sock with unrelated interrupted task's memcg. */ |
086f694a | 7281 | if (!in_task()) |
e876ecc6 SB |
7282 | return; |
7283 | ||
11092087 JW |
7284 | rcu_read_lock(); |
7285 | memcg = mem_cgroup_from_task(current); | |
7848ed62 | 7286 | if (mem_cgroup_is_root(memcg)) |
f7e1cb6e | 7287 | goto out; |
0db15298 | 7288 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcpmem_active) |
f7e1cb6e | 7289 | goto out; |
8965aa28 | 7290 | if (css_tryget(&memcg->css)) |
11092087 | 7291 | sk->sk_memcg = memcg; |
f7e1cb6e | 7292 | out: |
11092087 JW |
7293 | rcu_read_unlock(); |
7294 | } | |
11092087 | 7295 | |
2d758073 | 7296 | void mem_cgroup_sk_free(struct sock *sk) |
11092087 | 7297 | { |
2d758073 JW |
7298 | if (sk->sk_memcg) |
7299 | css_put(&sk->sk_memcg->css); | |
11092087 JW |
7300 | } |
7301 | ||
7302 | /** | |
7303 | * mem_cgroup_charge_skmem - charge socket memory | |
7304 | * @memcg: memcg to charge | |
7305 | * @nr_pages: number of pages to charge | |
4b1327be | 7306 | * @gfp_mask: reclaim mode |
11092087 JW |
7307 | * |
7308 | * Charges @nr_pages to @memcg. Returns %true if the charge fit within | |
4b1327be | 7309 | * @memcg's configured limit, %false if it doesn't. |
11092087 | 7310 | */ |
4b1327be WW |
7311 | bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages, |
7312 | gfp_t gfp_mask) | |
11092087 | 7313 | { |
f7e1cb6e | 7314 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 7315 | struct page_counter *fail; |
f7e1cb6e | 7316 | |
0db15298 JW |
7317 | if (page_counter_try_charge(&memcg->tcpmem, nr_pages, &fail)) { |
7318 | memcg->tcpmem_pressure = 0; | |
f7e1cb6e JW |
7319 | return true; |
7320 | } | |
0db15298 | 7321 | memcg->tcpmem_pressure = 1; |
4b1327be WW |
7322 | if (gfp_mask & __GFP_NOFAIL) { |
7323 | page_counter_charge(&memcg->tcpmem, nr_pages); | |
7324 | return true; | |
7325 | } | |
f7e1cb6e | 7326 | return false; |
11092087 | 7327 | } |
d886f4e4 | 7328 | |
4b1327be WW |
7329 | if (try_charge(memcg, gfp_mask, nr_pages) == 0) { |
7330 | mod_memcg_state(memcg, MEMCG_SOCK, nr_pages); | |
f7e1cb6e | 7331 | return true; |
4b1327be | 7332 | } |
f7e1cb6e | 7333 | |
11092087 JW |
7334 | return false; |
7335 | } | |
7336 | ||
7337 | /** | |
7338 | * mem_cgroup_uncharge_skmem - uncharge socket memory | |
b7701a5f MR |
7339 | * @memcg: memcg to uncharge |
7340 | * @nr_pages: number of pages to uncharge | |
11092087 JW |
7341 | */ |
7342 | void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) | |
7343 | { | |
f7e1cb6e | 7344 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 7345 | page_counter_uncharge(&memcg->tcpmem, nr_pages); |
f7e1cb6e JW |
7346 | return; |
7347 | } | |
d886f4e4 | 7348 | |
c9019e9b | 7349 | mod_memcg_state(memcg, MEMCG_SOCK, -nr_pages); |
b2807f07 | 7350 | |
475d0487 | 7351 | refill_stock(memcg, nr_pages); |
11092087 JW |
7352 | } |
7353 | ||
f7e1cb6e JW |
7354 | static int __init cgroup_memory(char *s) |
7355 | { | |
7356 | char *token; | |
7357 | ||
7358 | while ((token = strsep(&s, ",")) != NULL) { | |
7359 | if (!*token) | |
7360 | continue; | |
7361 | if (!strcmp(token, "nosocket")) | |
7362 | cgroup_memory_nosocket = true; | |
04823c83 VD |
7363 | if (!strcmp(token, "nokmem")) |
7364 | cgroup_memory_nokmem = true; | |
b6c1a8af YS |
7365 | if (!strcmp(token, "nobpf")) |
7366 | cgroup_memory_nobpf = true; | |
f7e1cb6e | 7367 | } |
460a79e1 | 7368 | return 1; |
f7e1cb6e JW |
7369 | } |
7370 | __setup("cgroup.memory=", cgroup_memory); | |
11092087 | 7371 | |
2d11085e | 7372 | /* |
1081312f MH |
7373 | * subsys_initcall() for memory controller. |
7374 | * | |
308167fc SAS |
7375 | * Some parts like memcg_hotplug_cpu_dead() have to be initialized from this |
7376 | * context because of lock dependencies (cgroup_lock -> cpu hotplug) but | |
7377 | * basically everything that doesn't depend on a specific mem_cgroup structure | |
7378 | * should be initialized from here. | |
2d11085e MH |
7379 | */ |
7380 | static int __init mem_cgroup_init(void) | |
7381 | { | |
95a045f6 JW |
7382 | int cpu, node; |
7383 | ||
f3344adf MS |
7384 | /* |
7385 | * Currently s32 type (can refer to struct batched_lruvec_stat) is | |
7386 | * used for per-memcg-per-cpu caching of per-node statistics. In order | |
7387 | * to work fine, we should make sure that the overfill threshold can't | |
7388 | * exceed S32_MAX / PAGE_SIZE. | |
7389 | */ | |
7390 | BUILD_BUG_ON(MEMCG_CHARGE_BATCH > S32_MAX / PAGE_SIZE); | |
7391 | ||
308167fc SAS |
7392 | cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL, |
7393 | memcg_hotplug_cpu_dead); | |
95a045f6 JW |
7394 | |
7395 | for_each_possible_cpu(cpu) | |
7396 | INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work, | |
7397 | drain_local_stock); | |
7398 | ||
7399 | for_each_node(node) { | |
7400 | struct mem_cgroup_tree_per_node *rtpn; | |
95a045f6 | 7401 | |
91f0dcce | 7402 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, node); |
95a045f6 | 7403 | |
ef8f2327 | 7404 | rtpn->rb_root = RB_ROOT; |
fa90b2fd | 7405 | rtpn->rb_rightmost = NULL; |
ef8f2327 | 7406 | spin_lock_init(&rtpn->lock); |
95a045f6 JW |
7407 | soft_limit_tree.rb_tree_per_node[node] = rtpn; |
7408 | } | |
7409 | ||
2d11085e MH |
7410 | return 0; |
7411 | } | |
7412 | subsys_initcall(mem_cgroup_init); | |
21afa38e | 7413 | |
e55b9f96 | 7414 | #ifdef CONFIG_SWAP |
358c07fc AB |
7415 | static struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg) |
7416 | { | |
1c2d479a | 7417 | while (!refcount_inc_not_zero(&memcg->id.ref)) { |
358c07fc AB |
7418 | /* |
7419 | * The root cgroup cannot be destroyed, so it's refcount must | |
7420 | * always be >= 1. | |
7421 | */ | |
7848ed62 | 7422 | if (WARN_ON_ONCE(mem_cgroup_is_root(memcg))) { |
358c07fc AB |
7423 | VM_BUG_ON(1); |
7424 | break; | |
7425 | } | |
7426 | memcg = parent_mem_cgroup(memcg); | |
7427 | if (!memcg) | |
7428 | memcg = root_mem_cgroup; | |
7429 | } | |
7430 | return memcg; | |
7431 | } | |
7432 | ||
21afa38e JW |
7433 | /** |
7434 | * mem_cgroup_swapout - transfer a memsw charge to swap | |
3ecb0087 | 7435 | * @folio: folio whose memsw charge to transfer |
21afa38e JW |
7436 | * @entry: swap entry to move the charge to |
7437 | * | |
3ecb0087 | 7438 | * Transfer the memsw charge of @folio to @entry. |
21afa38e | 7439 | */ |
3ecb0087 | 7440 | void mem_cgroup_swapout(struct folio *folio, swp_entry_t entry) |
21afa38e | 7441 | { |
1f47b61f | 7442 | struct mem_cgroup *memcg, *swap_memcg; |
d6810d73 | 7443 | unsigned int nr_entries; |
21afa38e JW |
7444 | unsigned short oldid; |
7445 | ||
3ecb0087 MWO |
7446 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
7447 | VM_BUG_ON_FOLIO(folio_ref_count(folio), folio); | |
21afa38e | 7448 | |
76358ab5 AS |
7449 | if (mem_cgroup_disabled()) |
7450 | return; | |
7451 | ||
b94c4e94 | 7452 | if (!do_memsw_account()) |
21afa38e JW |
7453 | return; |
7454 | ||
3ecb0087 | 7455 | memcg = folio_memcg(folio); |
21afa38e | 7456 | |
3ecb0087 | 7457 | VM_WARN_ON_ONCE_FOLIO(!memcg, folio); |
21afa38e JW |
7458 | if (!memcg) |
7459 | return; | |
7460 | ||
1f47b61f VD |
7461 | /* |
7462 | * In case the memcg owning these pages has been offlined and doesn't | |
7463 | * have an ID allocated to it anymore, charge the closest online | |
7464 | * ancestor for the swap instead and transfer the memory+swap charge. | |
7465 | */ | |
7466 | swap_memcg = mem_cgroup_id_get_online(memcg); | |
3ecb0087 | 7467 | nr_entries = folio_nr_pages(folio); |
d6810d73 HY |
7468 | /* Get references for the tail pages, too */ |
7469 | if (nr_entries > 1) | |
7470 | mem_cgroup_id_get_many(swap_memcg, nr_entries - 1); | |
7471 | oldid = swap_cgroup_record(entry, mem_cgroup_id(swap_memcg), | |
7472 | nr_entries); | |
3ecb0087 | 7473 | VM_BUG_ON_FOLIO(oldid, folio); |
c9019e9b | 7474 | mod_memcg_state(swap_memcg, MEMCG_SWAP, nr_entries); |
21afa38e | 7475 | |
3ecb0087 | 7476 | folio->memcg_data = 0; |
21afa38e JW |
7477 | |
7478 | if (!mem_cgroup_is_root(memcg)) | |
d6810d73 | 7479 | page_counter_uncharge(&memcg->memory, nr_entries); |
21afa38e | 7480 | |
b25806dc | 7481 | if (memcg != swap_memcg) { |
1f47b61f | 7482 | if (!mem_cgroup_is_root(swap_memcg)) |
d6810d73 HY |
7483 | page_counter_charge(&swap_memcg->memsw, nr_entries); |
7484 | page_counter_uncharge(&memcg->memsw, nr_entries); | |
1f47b61f VD |
7485 | } |
7486 | ||
ce9ce665 SAS |
7487 | /* |
7488 | * Interrupts should be disabled here because the caller holds the | |
b93b0163 | 7489 | * i_pages lock which is taken with interrupts-off. It is |
ce9ce665 | 7490 | * important here to have the interrupts disabled because it is the |
b93b0163 | 7491 | * only synchronisation we have for updating the per-CPU variables. |
ce9ce665 | 7492 | */ |
be3e67b5 | 7493 | memcg_stats_lock(); |
6e0110c2 | 7494 | mem_cgroup_charge_statistics(memcg, -nr_entries); |
be3e67b5 | 7495 | memcg_stats_unlock(); |
3ecb0087 | 7496 | memcg_check_events(memcg, folio_nid(folio)); |
73f576c0 | 7497 | |
1a3e1f40 | 7498 | css_put(&memcg->css); |
21afa38e JW |
7499 | } |
7500 | ||
38d8b4e6 | 7501 | /** |
e2e3fdc7 MWO |
7502 | * __mem_cgroup_try_charge_swap - try charging swap space for a folio |
7503 | * @folio: folio being added to swap | |
37e84351 VD |
7504 | * @entry: swap entry to charge |
7505 | * | |
e2e3fdc7 | 7506 | * Try to charge @folio's memcg for the swap space at @entry. |
37e84351 VD |
7507 | * |
7508 | * Returns 0 on success, -ENOMEM on failure. | |
7509 | */ | |
e2e3fdc7 | 7510 | int __mem_cgroup_try_charge_swap(struct folio *folio, swp_entry_t entry) |
37e84351 | 7511 | { |
e2e3fdc7 | 7512 | unsigned int nr_pages = folio_nr_pages(folio); |
37e84351 | 7513 | struct page_counter *counter; |
38d8b4e6 | 7514 | struct mem_cgroup *memcg; |
37e84351 VD |
7515 | unsigned short oldid; |
7516 | ||
b94c4e94 | 7517 | if (do_memsw_account()) |
37e84351 VD |
7518 | return 0; |
7519 | ||
e2e3fdc7 | 7520 | memcg = folio_memcg(folio); |
37e84351 | 7521 | |
e2e3fdc7 | 7522 | VM_WARN_ON_ONCE_FOLIO(!memcg, folio); |
37e84351 VD |
7523 | if (!memcg) |
7524 | return 0; | |
7525 | ||
f3a53a3a TH |
7526 | if (!entry.val) { |
7527 | memcg_memory_event(memcg, MEMCG_SWAP_FAIL); | |
bb98f2c5 | 7528 | return 0; |
f3a53a3a | 7529 | } |
bb98f2c5 | 7530 | |
1f47b61f VD |
7531 | memcg = mem_cgroup_id_get_online(memcg); |
7532 | ||
b25806dc | 7533 | if (!mem_cgroup_is_root(memcg) && |
38d8b4e6 | 7534 | !page_counter_try_charge(&memcg->swap, nr_pages, &counter)) { |
f3a53a3a TH |
7535 | memcg_memory_event(memcg, MEMCG_SWAP_MAX); |
7536 | memcg_memory_event(memcg, MEMCG_SWAP_FAIL); | |
1f47b61f | 7537 | mem_cgroup_id_put(memcg); |
37e84351 | 7538 | return -ENOMEM; |
1f47b61f | 7539 | } |
37e84351 | 7540 | |
38d8b4e6 HY |
7541 | /* Get references for the tail pages, too */ |
7542 | if (nr_pages > 1) | |
7543 | mem_cgroup_id_get_many(memcg, nr_pages - 1); | |
7544 | oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg), nr_pages); | |
e2e3fdc7 | 7545 | VM_BUG_ON_FOLIO(oldid, folio); |
c9019e9b | 7546 | mod_memcg_state(memcg, MEMCG_SWAP, nr_pages); |
37e84351 | 7547 | |
37e84351 VD |
7548 | return 0; |
7549 | } | |
7550 | ||
21afa38e | 7551 | /** |
01c4b28c | 7552 | * __mem_cgroup_uncharge_swap - uncharge swap space |
21afa38e | 7553 | * @entry: swap entry to uncharge |
38d8b4e6 | 7554 | * @nr_pages: the amount of swap space to uncharge |
21afa38e | 7555 | */ |
01c4b28c | 7556 | void __mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages) |
21afa38e JW |
7557 | { |
7558 | struct mem_cgroup *memcg; | |
7559 | unsigned short id; | |
7560 | ||
38d8b4e6 | 7561 | id = swap_cgroup_record(entry, 0, nr_pages); |
21afa38e | 7562 | rcu_read_lock(); |
adbe427b | 7563 | memcg = mem_cgroup_from_id(id); |
21afa38e | 7564 | if (memcg) { |
b25806dc | 7565 | if (!mem_cgroup_is_root(memcg)) { |
b94c4e94 | 7566 | if (do_memsw_account()) |
38d8b4e6 | 7567 | page_counter_uncharge(&memcg->memsw, nr_pages); |
b94c4e94 JW |
7568 | else |
7569 | page_counter_uncharge(&memcg->swap, nr_pages); | |
37e84351 | 7570 | } |
c9019e9b | 7571 | mod_memcg_state(memcg, MEMCG_SWAP, -nr_pages); |
38d8b4e6 | 7572 | mem_cgroup_id_put_many(memcg, nr_pages); |
21afa38e JW |
7573 | } |
7574 | rcu_read_unlock(); | |
7575 | } | |
7576 | ||
d8b38438 VD |
7577 | long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg) |
7578 | { | |
7579 | long nr_swap_pages = get_nr_swap_pages(); | |
7580 | ||
b25806dc | 7581 | if (mem_cgroup_disabled() || do_memsw_account()) |
d8b38438 | 7582 | return nr_swap_pages; |
7848ed62 | 7583 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) |
d8b38438 | 7584 | nr_swap_pages = min_t(long, nr_swap_pages, |
bbec2e15 | 7585 | READ_ONCE(memcg->swap.max) - |
d8b38438 VD |
7586 | page_counter_read(&memcg->swap)); |
7587 | return nr_swap_pages; | |
7588 | } | |
7589 | ||
9202d527 | 7590 | bool mem_cgroup_swap_full(struct folio *folio) |
5ccc5aba VD |
7591 | { |
7592 | struct mem_cgroup *memcg; | |
7593 | ||
9202d527 | 7594 | VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); |
5ccc5aba VD |
7595 | |
7596 | if (vm_swap_full()) | |
7597 | return true; | |
b25806dc | 7598 | if (do_memsw_account()) |
5ccc5aba VD |
7599 | return false; |
7600 | ||
9202d527 | 7601 | memcg = folio_memcg(folio); |
5ccc5aba VD |
7602 | if (!memcg) |
7603 | return false; | |
7604 | ||
7848ed62 | 7605 | for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) { |
4b82ab4f JK |
7606 | unsigned long usage = page_counter_read(&memcg->swap); |
7607 | ||
7608 | if (usage * 2 >= READ_ONCE(memcg->swap.high) || | |
7609 | usage * 2 >= READ_ONCE(memcg->swap.max)) | |
5ccc5aba | 7610 | return true; |
4b82ab4f | 7611 | } |
5ccc5aba VD |
7612 | |
7613 | return false; | |
7614 | } | |
7615 | ||
eccb52e7 | 7616 | static int __init setup_swap_account(char *s) |
21afa38e | 7617 | { |
b25806dc JW |
7618 | pr_warn_once("The swapaccount= commandline option is deprecated. " |
7619 | "Please report your usecase to linux-mm@kvack.org if you " | |
7620 | "depend on this functionality.\n"); | |
21afa38e JW |
7621 | return 1; |
7622 | } | |
eccb52e7 | 7623 | __setup("swapaccount=", setup_swap_account); |
21afa38e | 7624 | |
37e84351 VD |
7625 | static u64 swap_current_read(struct cgroup_subsys_state *css, |
7626 | struct cftype *cft) | |
7627 | { | |
7628 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
7629 | ||
7630 | return (u64)page_counter_read(&memcg->swap) * PAGE_SIZE; | |
7631 | } | |
7632 | ||
e0e0b412 LD |
7633 | static u64 swap_peak_read(struct cgroup_subsys_state *css, |
7634 | struct cftype *cft) | |
7635 | { | |
7636 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
7637 | ||
7638 | return (u64)memcg->swap.watermark * PAGE_SIZE; | |
7639 | } | |
7640 | ||
4b82ab4f JK |
7641 | static int swap_high_show(struct seq_file *m, void *v) |
7642 | { | |
7643 | return seq_puts_memcg_tunable(m, | |
7644 | READ_ONCE(mem_cgroup_from_seq(m)->swap.high)); | |
7645 | } | |
7646 | ||
7647 | static ssize_t swap_high_write(struct kernfs_open_file *of, | |
7648 | char *buf, size_t nbytes, loff_t off) | |
7649 | { | |
7650 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
7651 | unsigned long high; | |
7652 | int err; | |
7653 | ||
7654 | buf = strstrip(buf); | |
7655 | err = page_counter_memparse(buf, "max", &high); | |
7656 | if (err) | |
7657 | return err; | |
7658 | ||
7659 | page_counter_set_high(&memcg->swap, high); | |
7660 | ||
7661 | return nbytes; | |
7662 | } | |
7663 | ||
37e84351 VD |
7664 | static int swap_max_show(struct seq_file *m, void *v) |
7665 | { | |
677dc973 CD |
7666 | return seq_puts_memcg_tunable(m, |
7667 | READ_ONCE(mem_cgroup_from_seq(m)->swap.max)); | |
37e84351 VD |
7668 | } |
7669 | ||
7670 | static ssize_t swap_max_write(struct kernfs_open_file *of, | |
7671 | char *buf, size_t nbytes, loff_t off) | |
7672 | { | |
7673 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
7674 | unsigned long max; | |
7675 | int err; | |
7676 | ||
7677 | buf = strstrip(buf); | |
7678 | err = page_counter_memparse(buf, "max", &max); | |
7679 | if (err) | |
7680 | return err; | |
7681 | ||
be09102b | 7682 | xchg(&memcg->swap.max, max); |
37e84351 VD |
7683 | |
7684 | return nbytes; | |
7685 | } | |
7686 | ||
f3a53a3a TH |
7687 | static int swap_events_show(struct seq_file *m, void *v) |
7688 | { | |
aa9694bb | 7689 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
f3a53a3a | 7690 | |
4b82ab4f JK |
7691 | seq_printf(m, "high %lu\n", |
7692 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_HIGH])); | |
f3a53a3a TH |
7693 | seq_printf(m, "max %lu\n", |
7694 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_MAX])); | |
7695 | seq_printf(m, "fail %lu\n", | |
7696 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_FAIL])); | |
7697 | ||
7698 | return 0; | |
7699 | } | |
7700 | ||
37e84351 VD |
7701 | static struct cftype swap_files[] = { |
7702 | { | |
7703 | .name = "swap.current", | |
7704 | .flags = CFTYPE_NOT_ON_ROOT, | |
7705 | .read_u64 = swap_current_read, | |
7706 | }, | |
4b82ab4f JK |
7707 | { |
7708 | .name = "swap.high", | |
7709 | .flags = CFTYPE_NOT_ON_ROOT, | |
7710 | .seq_show = swap_high_show, | |
7711 | .write = swap_high_write, | |
7712 | }, | |
37e84351 VD |
7713 | { |
7714 | .name = "swap.max", | |
7715 | .flags = CFTYPE_NOT_ON_ROOT, | |
7716 | .seq_show = swap_max_show, | |
7717 | .write = swap_max_write, | |
7718 | }, | |
e0e0b412 LD |
7719 | { |
7720 | .name = "swap.peak", | |
7721 | .flags = CFTYPE_NOT_ON_ROOT, | |
7722 | .read_u64 = swap_peak_read, | |
7723 | }, | |
f3a53a3a TH |
7724 | { |
7725 | .name = "swap.events", | |
7726 | .flags = CFTYPE_NOT_ON_ROOT, | |
7727 | .file_offset = offsetof(struct mem_cgroup, swap_events_file), | |
7728 | .seq_show = swap_events_show, | |
7729 | }, | |
37e84351 VD |
7730 | { } /* terminate */ |
7731 | }; | |
7732 | ||
eccb52e7 | 7733 | static struct cftype memsw_files[] = { |
21afa38e JW |
7734 | { |
7735 | .name = "memsw.usage_in_bytes", | |
7736 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
7737 | .read_u64 = mem_cgroup_read_u64, | |
7738 | }, | |
7739 | { | |
7740 | .name = "memsw.max_usage_in_bytes", | |
7741 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
7742 | .write = mem_cgroup_reset, | |
7743 | .read_u64 = mem_cgroup_read_u64, | |
7744 | }, | |
7745 | { | |
7746 | .name = "memsw.limit_in_bytes", | |
7747 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
7748 | .write = mem_cgroup_write, | |
7749 | .read_u64 = mem_cgroup_read_u64, | |
7750 | }, | |
7751 | { | |
7752 | .name = "memsw.failcnt", | |
7753 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
7754 | .write = mem_cgroup_reset, | |
7755 | .read_u64 = mem_cgroup_read_u64, | |
7756 | }, | |
7757 | { }, /* terminate */ | |
7758 | }; | |
7759 | ||
f4840ccf JW |
7760 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
7761 | /** | |
7762 | * obj_cgroup_may_zswap - check if this cgroup can zswap | |
7763 | * @objcg: the object cgroup | |
7764 | * | |
7765 | * Check if the hierarchical zswap limit has been reached. | |
7766 | * | |
7767 | * This doesn't check for specific headroom, and it is not atomic | |
7768 | * either. But with zswap, the size of the allocation is only known | |
7769 | * once compression has occured, and this optimistic pre-check avoids | |
7770 | * spending cycles on compression when there is already no room left | |
7771 | * or zswap is disabled altogether somewhere in the hierarchy. | |
7772 | */ | |
7773 | bool obj_cgroup_may_zswap(struct obj_cgroup *objcg) | |
7774 | { | |
7775 | struct mem_cgroup *memcg, *original_memcg; | |
7776 | bool ret = true; | |
7777 | ||
7778 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
7779 | return true; | |
7780 | ||
7781 | original_memcg = get_mem_cgroup_from_objcg(objcg); | |
7848ed62 | 7782 | for (memcg = original_memcg; !mem_cgroup_is_root(memcg); |
f4840ccf JW |
7783 | memcg = parent_mem_cgroup(memcg)) { |
7784 | unsigned long max = READ_ONCE(memcg->zswap_max); | |
7785 | unsigned long pages; | |
7786 | ||
7787 | if (max == PAGE_COUNTER_MAX) | |
7788 | continue; | |
7789 | if (max == 0) { | |
7790 | ret = false; | |
7791 | break; | |
7792 | } | |
7793 | ||
7794 | cgroup_rstat_flush(memcg->css.cgroup); | |
7795 | pages = memcg_page_state(memcg, MEMCG_ZSWAP_B) / PAGE_SIZE; | |
7796 | if (pages < max) | |
7797 | continue; | |
7798 | ret = false; | |
7799 | break; | |
7800 | } | |
7801 | mem_cgroup_put(original_memcg); | |
7802 | return ret; | |
7803 | } | |
7804 | ||
7805 | /** | |
7806 | * obj_cgroup_charge_zswap - charge compression backend memory | |
7807 | * @objcg: the object cgroup | |
7808 | * @size: size of compressed object | |
7809 | * | |
3a1060c2 | 7810 | * This forces the charge after obj_cgroup_may_zswap() allowed |
f4840ccf JW |
7811 | * compression and storage in zwap for this cgroup to go ahead. |
7812 | */ | |
7813 | void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size) | |
7814 | { | |
7815 | struct mem_cgroup *memcg; | |
7816 | ||
7817 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
7818 | return; | |
7819 | ||
7820 | VM_WARN_ON_ONCE(!(current->flags & PF_MEMALLOC)); | |
7821 | ||
7822 | /* PF_MEMALLOC context, charging must succeed */ | |
7823 | if (obj_cgroup_charge(objcg, GFP_KERNEL, size)) | |
7824 | VM_WARN_ON_ONCE(1); | |
7825 | ||
7826 | rcu_read_lock(); | |
7827 | memcg = obj_cgroup_memcg(objcg); | |
7828 | mod_memcg_state(memcg, MEMCG_ZSWAP_B, size); | |
7829 | mod_memcg_state(memcg, MEMCG_ZSWAPPED, 1); | |
7830 | rcu_read_unlock(); | |
7831 | } | |
7832 | ||
7833 | /** | |
7834 | * obj_cgroup_uncharge_zswap - uncharge compression backend memory | |
7835 | * @objcg: the object cgroup | |
7836 | * @size: size of compressed object | |
7837 | * | |
7838 | * Uncharges zswap memory on page in. | |
7839 | */ | |
7840 | void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size) | |
7841 | { | |
7842 | struct mem_cgroup *memcg; | |
7843 | ||
7844 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
7845 | return; | |
7846 | ||
7847 | obj_cgroup_uncharge(objcg, size); | |
7848 | ||
7849 | rcu_read_lock(); | |
7850 | memcg = obj_cgroup_memcg(objcg); | |
7851 | mod_memcg_state(memcg, MEMCG_ZSWAP_B, -size); | |
7852 | mod_memcg_state(memcg, MEMCG_ZSWAPPED, -1); | |
7853 | rcu_read_unlock(); | |
7854 | } | |
7855 | ||
7856 | static u64 zswap_current_read(struct cgroup_subsys_state *css, | |
7857 | struct cftype *cft) | |
7858 | { | |
7859 | cgroup_rstat_flush(css->cgroup); | |
7860 | return memcg_page_state(mem_cgroup_from_css(css), MEMCG_ZSWAP_B); | |
7861 | } | |
7862 | ||
7863 | static int zswap_max_show(struct seq_file *m, void *v) | |
7864 | { | |
7865 | return seq_puts_memcg_tunable(m, | |
7866 | READ_ONCE(mem_cgroup_from_seq(m)->zswap_max)); | |
7867 | } | |
7868 | ||
7869 | static ssize_t zswap_max_write(struct kernfs_open_file *of, | |
7870 | char *buf, size_t nbytes, loff_t off) | |
7871 | { | |
7872 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
7873 | unsigned long max; | |
7874 | int err; | |
7875 | ||
7876 | buf = strstrip(buf); | |
7877 | err = page_counter_memparse(buf, "max", &max); | |
7878 | if (err) | |
7879 | return err; | |
7880 | ||
7881 | xchg(&memcg->zswap_max, max); | |
7882 | ||
7883 | return nbytes; | |
7884 | } | |
7885 | ||
7886 | static struct cftype zswap_files[] = { | |
7887 | { | |
7888 | .name = "zswap.current", | |
7889 | .flags = CFTYPE_NOT_ON_ROOT, | |
7890 | .read_u64 = zswap_current_read, | |
7891 | }, | |
7892 | { | |
7893 | .name = "zswap.max", | |
7894 | .flags = CFTYPE_NOT_ON_ROOT, | |
7895 | .seq_show = zswap_max_show, | |
7896 | .write = zswap_max_write, | |
7897 | }, | |
7898 | { } /* terminate */ | |
7899 | }; | |
7900 | #endif /* CONFIG_MEMCG_KMEM && CONFIG_ZSWAP */ | |
7901 | ||
21afa38e JW |
7902 | static int __init mem_cgroup_swap_init(void) |
7903 | { | |
2d1c4980 | 7904 | if (mem_cgroup_disabled()) |
eccb52e7 JW |
7905 | return 0; |
7906 | ||
7907 | WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, swap_files)); | |
7908 | WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, memsw_files)); | |
f4840ccf JW |
7909 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
7910 | WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, zswap_files)); | |
7911 | #endif | |
21afa38e JW |
7912 | return 0; |
7913 | } | |
b25806dc | 7914 | subsys_initcall(mem_cgroup_swap_init); |
21afa38e | 7915 | |
e55b9f96 | 7916 | #endif /* CONFIG_SWAP */ |