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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> |
08e552c6 | 66 | #include "internal.h" |
d1a4c0b3 | 67 | #include <net/sock.h> |
4bd2c1ee | 68 | #include <net/ip.h> |
f35c3a8e | 69 | #include "slab.h" |
014bb1de | 70 | #include "swap.h" |
8cdea7c0 | 71 | |
7c0f6ba6 | 72 | #include <linux/uaccess.h> |
8697d331 | 73 | |
cc8e970c KM |
74 | #include <trace/events/vmscan.h> |
75 | ||
073219e9 TH |
76 | struct cgroup_subsys memory_cgrp_subsys __read_mostly; |
77 | EXPORT_SYMBOL(memory_cgrp_subsys); | |
68ae564b | 78 | |
7d828602 JW |
79 | struct mem_cgroup *root_mem_cgroup __read_mostly; |
80 | ||
37d5985c RG |
81 | /* Active memory cgroup to use from an interrupt context */ |
82 | DEFINE_PER_CPU(struct mem_cgroup *, int_active_memcg); | |
c74d40e8 | 83 | EXPORT_PER_CPU_SYMBOL_GPL(int_active_memcg); |
37d5985c | 84 | |
f7e1cb6e | 85 | /* Socket memory accounting disabled? */ |
0f0cace3 | 86 | static bool cgroup_memory_nosocket __ro_after_init; |
f7e1cb6e | 87 | |
04823c83 | 88 | /* Kernel memory accounting disabled? */ |
17c17367 | 89 | static bool cgroup_memory_nokmem __ro_after_init; |
04823c83 | 90 | |
21afa38e | 91 | /* Whether the swap controller is active */ |
c255a458 | 92 | #ifdef CONFIG_MEMCG_SWAP |
ef7a4ffc | 93 | static bool cgroup_memory_noswap __ro_after_init; |
c077719b | 94 | #else |
eccb52e7 | 95 | #define cgroup_memory_noswap 1 |
2d1c4980 | 96 | #endif |
c077719b | 97 | |
97b27821 TH |
98 | #ifdef CONFIG_CGROUP_WRITEBACK |
99 | static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq); | |
100 | #endif | |
101 | ||
7941d214 JW |
102 | /* Whether legacy memory+swap accounting is active */ |
103 | static bool do_memsw_account(void) | |
104 | { | |
eccb52e7 | 105 | return !cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_noswap; |
7941d214 JW |
106 | } |
107 | ||
a0db00fc KS |
108 | #define THRESHOLDS_EVENTS_TARGET 128 |
109 | #define SOFTLIMIT_EVENTS_TARGET 1024 | |
e9f8974f | 110 | |
bb4cc1a8 AM |
111 | /* |
112 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
113 | * their hierarchy representation | |
114 | */ | |
115 | ||
ef8f2327 | 116 | struct mem_cgroup_tree_per_node { |
bb4cc1a8 | 117 | struct rb_root rb_root; |
fa90b2fd | 118 | struct rb_node *rb_rightmost; |
bb4cc1a8 AM |
119 | spinlock_t lock; |
120 | }; | |
121 | ||
bb4cc1a8 AM |
122 | struct mem_cgroup_tree { |
123 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
124 | }; | |
125 | ||
126 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
127 | ||
9490ff27 KH |
128 | /* for OOM */ |
129 | struct mem_cgroup_eventfd_list { | |
130 | struct list_head list; | |
131 | struct eventfd_ctx *eventfd; | |
132 | }; | |
2e72b634 | 133 | |
79bd9814 TH |
134 | /* |
135 | * cgroup_event represents events which userspace want to receive. | |
136 | */ | |
3bc942f3 | 137 | struct mem_cgroup_event { |
79bd9814 | 138 | /* |
59b6f873 | 139 | * memcg which the event belongs to. |
79bd9814 | 140 | */ |
59b6f873 | 141 | struct mem_cgroup *memcg; |
79bd9814 TH |
142 | /* |
143 | * eventfd to signal userspace about the event. | |
144 | */ | |
145 | struct eventfd_ctx *eventfd; | |
146 | /* | |
147 | * Each of these stored in a list by the cgroup. | |
148 | */ | |
149 | struct list_head list; | |
fba94807 TH |
150 | /* |
151 | * register_event() callback will be used to add new userspace | |
152 | * waiter for changes related to this event. Use eventfd_signal() | |
153 | * on eventfd to send notification to userspace. | |
154 | */ | |
59b6f873 | 155 | int (*register_event)(struct mem_cgroup *memcg, |
347c4a87 | 156 | struct eventfd_ctx *eventfd, const char *args); |
fba94807 TH |
157 | /* |
158 | * unregister_event() callback will be called when userspace closes | |
159 | * the eventfd or on cgroup removing. This callback must be set, | |
160 | * if you want provide notification functionality. | |
161 | */ | |
59b6f873 | 162 | void (*unregister_event)(struct mem_cgroup *memcg, |
fba94807 | 163 | struct eventfd_ctx *eventfd); |
79bd9814 TH |
164 | /* |
165 | * All fields below needed to unregister event when | |
166 | * userspace closes eventfd. | |
167 | */ | |
168 | poll_table pt; | |
169 | wait_queue_head_t *wqh; | |
ac6424b9 | 170 | wait_queue_entry_t wait; |
79bd9814 TH |
171 | struct work_struct remove; |
172 | }; | |
173 | ||
c0ff4b85 R |
174 | static void mem_cgroup_threshold(struct mem_cgroup *memcg); |
175 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); | |
2e72b634 | 176 | |
7dc74be0 DN |
177 | /* Stuffs for move charges at task migration. */ |
178 | /* | |
1dfab5ab | 179 | * Types of charges to be moved. |
7dc74be0 | 180 | */ |
1dfab5ab JW |
181 | #define MOVE_ANON 0x1U |
182 | #define MOVE_FILE 0x2U | |
183 | #define MOVE_MASK (MOVE_ANON | MOVE_FILE) | |
7dc74be0 | 184 | |
4ffef5fe DN |
185 | /* "mc" and its members are protected by cgroup_mutex */ |
186 | static struct move_charge_struct { | |
b1dd693e | 187 | spinlock_t lock; /* for from, to */ |
264a0ae1 | 188 | struct mm_struct *mm; |
4ffef5fe DN |
189 | struct mem_cgroup *from; |
190 | struct mem_cgroup *to; | |
1dfab5ab | 191 | unsigned long flags; |
4ffef5fe | 192 | unsigned long precharge; |
854ffa8d | 193 | unsigned long moved_charge; |
483c30b5 | 194 | unsigned long moved_swap; |
8033b97c DN |
195 | struct task_struct *moving_task; /* a task moving charges */ |
196 | wait_queue_head_t waitq; /* a waitq for other context */ | |
197 | } mc = { | |
2bd9bb20 | 198 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
199 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
200 | }; | |
4ffef5fe | 201 | |
4e416953 BS |
202 | /* |
203 | * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft | |
204 | * limit reclaim to prevent infinite loops, if they ever occur. | |
205 | */ | |
a0db00fc | 206 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS 100 |
bb4cc1a8 | 207 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS 2 |
4e416953 | 208 | |
8c7c6e34 | 209 | /* for encoding cft->private value on file */ |
86ae53e1 GC |
210 | enum res_type { |
211 | _MEM, | |
212 | _MEMSWAP, | |
510fc4e1 | 213 | _KMEM, |
d55f90bf | 214 | _TCP, |
86ae53e1 GC |
215 | }; |
216 | ||
a0db00fc KS |
217 | #define MEMFILE_PRIVATE(x, val) ((x) << 16 | (val)) |
218 | #define MEMFILE_TYPE(val) ((val) >> 16 & 0xffff) | |
8c7c6e34 KH |
219 | #define MEMFILE_ATTR(val) ((val) & 0xffff) |
220 | ||
b05706f1 KT |
221 | /* |
222 | * Iteration constructs for visiting all cgroups (under a tree). If | |
223 | * loops are exited prematurely (break), mem_cgroup_iter_break() must | |
224 | * be used for reference counting. | |
225 | */ | |
226 | #define for_each_mem_cgroup_tree(iter, root) \ | |
227 | for (iter = mem_cgroup_iter(root, NULL, NULL); \ | |
228 | iter != NULL; \ | |
229 | iter = mem_cgroup_iter(root, iter, NULL)) | |
230 | ||
231 | #define for_each_mem_cgroup(iter) \ | |
232 | for (iter = mem_cgroup_iter(NULL, NULL, NULL); \ | |
233 | iter != NULL; \ | |
234 | iter = mem_cgroup_iter(NULL, iter, NULL)) | |
235 | ||
a4ebf1b6 | 236 | static inline bool task_is_dying(void) |
7775face TH |
237 | { |
238 | return tsk_is_oom_victim(current) || fatal_signal_pending(current) || | |
239 | (current->flags & PF_EXITING); | |
240 | } | |
241 | ||
70ddf637 AV |
242 | /* Some nice accessors for the vmpressure. */ |
243 | struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg) | |
244 | { | |
245 | if (!memcg) | |
246 | memcg = root_mem_cgroup; | |
247 | return &memcg->vmpressure; | |
248 | } | |
249 | ||
9647875b | 250 | struct mem_cgroup *vmpressure_to_memcg(struct vmpressure *vmpr) |
70ddf637 | 251 | { |
9647875b | 252 | return container_of(vmpr, struct mem_cgroup, vmpressure); |
70ddf637 AV |
253 | } |
254 | ||
84c07d11 | 255 | #ifdef CONFIG_MEMCG_KMEM |
0764db9b | 256 | static DEFINE_SPINLOCK(objcg_lock); |
bf4f0599 | 257 | |
4d5c8aed RG |
258 | bool mem_cgroup_kmem_disabled(void) |
259 | { | |
260 | return cgroup_memory_nokmem; | |
261 | } | |
262 | ||
f1286fae MS |
263 | static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, |
264 | unsigned int nr_pages); | |
c1a660de | 265 | |
bf4f0599 RG |
266 | static void obj_cgroup_release(struct percpu_ref *ref) |
267 | { | |
268 | struct obj_cgroup *objcg = container_of(ref, struct obj_cgroup, refcnt); | |
bf4f0599 RG |
269 | unsigned int nr_bytes; |
270 | unsigned int nr_pages; | |
271 | unsigned long flags; | |
272 | ||
273 | /* | |
274 | * At this point all allocated objects are freed, and | |
275 | * objcg->nr_charged_bytes can't have an arbitrary byte value. | |
276 | * However, it can be PAGE_SIZE or (x * PAGE_SIZE). | |
277 | * | |
278 | * The following sequence can lead to it: | |
279 | * 1) CPU0: objcg == stock->cached_objcg | |
280 | * 2) CPU1: we do a small allocation (e.g. 92 bytes), | |
281 | * PAGE_SIZE bytes are charged | |
282 | * 3) CPU1: a process from another memcg is allocating something, | |
283 | * the stock if flushed, | |
284 | * objcg->nr_charged_bytes = PAGE_SIZE - 92 | |
285 | * 5) CPU0: we do release this object, | |
286 | * 92 bytes are added to stock->nr_bytes | |
287 | * 6) CPU0: stock is flushed, | |
288 | * 92 bytes are added to objcg->nr_charged_bytes | |
289 | * | |
290 | * In the result, nr_charged_bytes == PAGE_SIZE. | |
291 | * This page will be uncharged in obj_cgroup_release(). | |
292 | */ | |
293 | nr_bytes = atomic_read(&objcg->nr_charged_bytes); | |
294 | WARN_ON_ONCE(nr_bytes & (PAGE_SIZE - 1)); | |
295 | nr_pages = nr_bytes >> PAGE_SHIFT; | |
296 | ||
bf4f0599 | 297 | if (nr_pages) |
f1286fae | 298 | obj_cgroup_uncharge_pages(objcg, nr_pages); |
271dd6b1 | 299 | |
0764db9b | 300 | spin_lock_irqsave(&objcg_lock, flags); |
bf4f0599 | 301 | list_del(&objcg->list); |
0764db9b | 302 | spin_unlock_irqrestore(&objcg_lock, flags); |
bf4f0599 RG |
303 | |
304 | percpu_ref_exit(ref); | |
305 | kfree_rcu(objcg, rcu); | |
306 | } | |
307 | ||
308 | static struct obj_cgroup *obj_cgroup_alloc(void) | |
309 | { | |
310 | struct obj_cgroup *objcg; | |
311 | int ret; | |
312 | ||
313 | objcg = kzalloc(sizeof(struct obj_cgroup), GFP_KERNEL); | |
314 | if (!objcg) | |
315 | return NULL; | |
316 | ||
317 | ret = percpu_ref_init(&objcg->refcnt, obj_cgroup_release, 0, | |
318 | GFP_KERNEL); | |
319 | if (ret) { | |
320 | kfree(objcg); | |
321 | return NULL; | |
322 | } | |
323 | INIT_LIST_HEAD(&objcg->list); | |
324 | return objcg; | |
325 | } | |
326 | ||
327 | static void memcg_reparent_objcgs(struct mem_cgroup *memcg, | |
328 | struct mem_cgroup *parent) | |
329 | { | |
330 | struct obj_cgroup *objcg, *iter; | |
331 | ||
332 | objcg = rcu_replace_pointer(memcg->objcg, NULL, true); | |
333 | ||
0764db9b | 334 | spin_lock_irq(&objcg_lock); |
bf4f0599 | 335 | |
9838354e MS |
336 | /* 1) Ready to reparent active objcg. */ |
337 | list_add(&objcg->list, &memcg->objcg_list); | |
338 | /* 2) Reparent active objcg and already reparented objcgs to parent. */ | |
339 | list_for_each_entry(iter, &memcg->objcg_list, list) | |
340 | WRITE_ONCE(iter->memcg, parent); | |
341 | /* 3) Move already reparented objcgs to the parent's list */ | |
bf4f0599 RG |
342 | list_splice(&memcg->objcg_list, &parent->objcg_list); |
343 | ||
0764db9b | 344 | spin_unlock_irq(&objcg_lock); |
bf4f0599 RG |
345 | |
346 | percpu_ref_kill(&objcg->refcnt); | |
347 | } | |
348 | ||
d7f25f8a GC |
349 | /* |
350 | * A lot of the calls to the cache allocation functions are expected to be | |
272911a4 | 351 | * inlined by the compiler. Since the calls to memcg_slab_pre_alloc_hook() are |
d7f25f8a GC |
352 | * conditional to this static branch, we'll have to allow modules that does |
353 | * kmem_cache_alloc and the such to see this symbol as well | |
354 | */ | |
ef12947c | 355 | DEFINE_STATIC_KEY_FALSE(memcg_kmem_enabled_key); |
d7f25f8a | 356 | EXPORT_SYMBOL(memcg_kmem_enabled_key); |
0a432dcb | 357 | #endif |
17cc4dfe | 358 | |
ad7fa852 TH |
359 | /** |
360 | * mem_cgroup_css_from_page - css of the memcg associated with a page | |
361 | * @page: page of interest | |
362 | * | |
363 | * If memcg is bound to the default hierarchy, css of the memcg associated | |
364 | * with @page is returned. The returned css remains associated with @page | |
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 TH |
369 | */ |
370 | struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page) | |
371 | { | |
372 | struct mem_cgroup *memcg; | |
373 | ||
bcfe06bf | 374 | memcg = page_memcg(page); |
ad7fa852 | 375 | |
9e10a130 | 376 | if (!memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
ad7fa852 TH |
377 | memcg = root_mem_cgroup; |
378 | ||
ad7fa852 TH |
379 | return &memcg->css; |
380 | } | |
381 | ||
2fc04524 VD |
382 | /** |
383 | * page_cgroup_ino - return inode number of the memcg a page is charged to | |
384 | * @page: the page | |
385 | * | |
386 | * Look up the closest online ancestor of the memory cgroup @page is charged to | |
387 | * and return its inode number or 0 if @page is not charged to any cgroup. It | |
388 | * is safe to call this function without holding a reference to @page. | |
389 | * | |
390 | * Note, this function is inherently racy, because there is nothing to prevent | |
391 | * the cgroup inode from getting torn down and potentially reallocated a moment | |
392 | * after page_cgroup_ino() returns, so it only should be used by callers that | |
393 | * do not care (such as procfs interfaces). | |
394 | */ | |
395 | ino_t page_cgroup_ino(struct page *page) | |
396 | { | |
397 | struct mem_cgroup *memcg; | |
398 | unsigned long ino = 0; | |
399 | ||
400 | rcu_read_lock(); | |
bcfe06bf | 401 | memcg = page_memcg_check(page); |
286e04b8 | 402 | |
2fc04524 VD |
403 | while (memcg && !(memcg->css.flags & CSS_ONLINE)) |
404 | memcg = parent_mem_cgroup(memcg); | |
405 | if (memcg) | |
406 | ino = cgroup_ino(memcg->css.cgroup); | |
407 | rcu_read_unlock(); | |
408 | return ino; | |
409 | } | |
410 | ||
ef8f2327 MG |
411 | static void __mem_cgroup_insert_exceeded(struct mem_cgroup_per_node *mz, |
412 | struct mem_cgroup_tree_per_node *mctz, | |
3e32cb2e | 413 | unsigned long new_usage_in_excess) |
bb4cc1a8 AM |
414 | { |
415 | struct rb_node **p = &mctz->rb_root.rb_node; | |
416 | struct rb_node *parent = NULL; | |
ef8f2327 | 417 | struct mem_cgroup_per_node *mz_node; |
fa90b2fd | 418 | bool rightmost = true; |
bb4cc1a8 AM |
419 | |
420 | if (mz->on_tree) | |
421 | return; | |
422 | ||
423 | mz->usage_in_excess = new_usage_in_excess; | |
424 | if (!mz->usage_in_excess) | |
425 | return; | |
426 | while (*p) { | |
427 | parent = *p; | |
ef8f2327 | 428 | mz_node = rb_entry(parent, struct mem_cgroup_per_node, |
bb4cc1a8 | 429 | tree_node); |
fa90b2fd | 430 | if (mz->usage_in_excess < mz_node->usage_in_excess) { |
bb4cc1a8 | 431 | p = &(*p)->rb_left; |
fa90b2fd | 432 | rightmost = false; |
378876b0 | 433 | } else { |
bb4cc1a8 | 434 | p = &(*p)->rb_right; |
378876b0 | 435 | } |
bb4cc1a8 | 436 | } |
fa90b2fd DB |
437 | |
438 | if (rightmost) | |
439 | mctz->rb_rightmost = &mz->tree_node; | |
440 | ||
bb4cc1a8 AM |
441 | rb_link_node(&mz->tree_node, parent, p); |
442 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
443 | mz->on_tree = true; | |
444 | } | |
445 | ||
ef8f2327 MG |
446 | static void __mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz, |
447 | struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 AM |
448 | { |
449 | if (!mz->on_tree) | |
450 | return; | |
fa90b2fd DB |
451 | |
452 | if (&mz->tree_node == mctz->rb_rightmost) | |
453 | mctz->rb_rightmost = rb_prev(&mz->tree_node); | |
454 | ||
bb4cc1a8 AM |
455 | rb_erase(&mz->tree_node, &mctz->rb_root); |
456 | mz->on_tree = false; | |
457 | } | |
458 | ||
ef8f2327 MG |
459 | static void mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz, |
460 | struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 461 | { |
0a31bc97 JW |
462 | unsigned long flags; |
463 | ||
464 | spin_lock_irqsave(&mctz->lock, flags); | |
cf2c8127 | 465 | __mem_cgroup_remove_exceeded(mz, mctz); |
0a31bc97 | 466 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
467 | } |
468 | ||
3e32cb2e JW |
469 | static unsigned long soft_limit_excess(struct mem_cgroup *memcg) |
470 | { | |
471 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
4db0c3c2 | 472 | unsigned long soft_limit = READ_ONCE(memcg->soft_limit); |
3e32cb2e JW |
473 | unsigned long excess = 0; |
474 | ||
475 | if (nr_pages > soft_limit) | |
476 | excess = nr_pages - soft_limit; | |
477 | ||
478 | return excess; | |
479 | } | |
bb4cc1a8 | 480 | |
658b69c9 | 481 | static void mem_cgroup_update_tree(struct mem_cgroup *memcg, int nid) |
bb4cc1a8 | 482 | { |
3e32cb2e | 483 | unsigned long excess; |
ef8f2327 MG |
484 | struct mem_cgroup_per_node *mz; |
485 | struct mem_cgroup_tree_per_node *mctz; | |
bb4cc1a8 | 486 | |
2ab082ba | 487 | mctz = soft_limit_tree.rb_tree_per_node[nid]; |
bfc7228b LD |
488 | if (!mctz) |
489 | return; | |
bb4cc1a8 AM |
490 | /* |
491 | * Necessary to update all ancestors when hierarchy is used. | |
492 | * because their event counter is not touched. | |
493 | */ | |
494 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
658b69c9 | 495 | mz = memcg->nodeinfo[nid]; |
3e32cb2e | 496 | excess = soft_limit_excess(memcg); |
bb4cc1a8 AM |
497 | /* |
498 | * We have to update the tree if mz is on RB-tree or | |
499 | * mem is over its softlimit. | |
500 | */ | |
501 | if (excess || mz->on_tree) { | |
0a31bc97 JW |
502 | unsigned long flags; |
503 | ||
504 | spin_lock_irqsave(&mctz->lock, flags); | |
bb4cc1a8 AM |
505 | /* if on-tree, remove it */ |
506 | if (mz->on_tree) | |
cf2c8127 | 507 | __mem_cgroup_remove_exceeded(mz, mctz); |
bb4cc1a8 AM |
508 | /* |
509 | * Insert again. mz->usage_in_excess will be updated. | |
510 | * If excess is 0, no tree ops. | |
511 | */ | |
cf2c8127 | 512 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 513 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
514 | } |
515 | } | |
516 | } | |
517 | ||
518 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) | |
519 | { | |
ef8f2327 MG |
520 | struct mem_cgroup_tree_per_node *mctz; |
521 | struct mem_cgroup_per_node *mz; | |
522 | int nid; | |
bb4cc1a8 | 523 | |
e231875b | 524 | for_each_node(nid) { |
a3747b53 | 525 | mz = memcg->nodeinfo[nid]; |
2ab082ba | 526 | mctz = soft_limit_tree.rb_tree_per_node[nid]; |
bfc7228b LD |
527 | if (mctz) |
528 | mem_cgroup_remove_exceeded(mz, mctz); | |
bb4cc1a8 AM |
529 | } |
530 | } | |
531 | ||
ef8f2327 MG |
532 | static struct mem_cgroup_per_node * |
533 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 534 | { |
ef8f2327 | 535 | struct mem_cgroup_per_node *mz; |
bb4cc1a8 AM |
536 | |
537 | retry: | |
538 | mz = NULL; | |
fa90b2fd | 539 | if (!mctz->rb_rightmost) |
bb4cc1a8 AM |
540 | goto done; /* Nothing to reclaim from */ |
541 | ||
fa90b2fd DB |
542 | mz = rb_entry(mctz->rb_rightmost, |
543 | struct mem_cgroup_per_node, tree_node); | |
bb4cc1a8 AM |
544 | /* |
545 | * Remove the node now but someone else can add it back, | |
546 | * we will to add it back at the end of reclaim to its correct | |
547 | * position in the tree. | |
548 | */ | |
cf2c8127 | 549 | __mem_cgroup_remove_exceeded(mz, mctz); |
3e32cb2e | 550 | if (!soft_limit_excess(mz->memcg) || |
8965aa28 | 551 | !css_tryget(&mz->memcg->css)) |
bb4cc1a8 AM |
552 | goto retry; |
553 | done: | |
554 | return mz; | |
555 | } | |
556 | ||
ef8f2327 MG |
557 | static struct mem_cgroup_per_node * |
558 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 559 | { |
ef8f2327 | 560 | struct mem_cgroup_per_node *mz; |
bb4cc1a8 | 561 | |
0a31bc97 | 562 | spin_lock_irq(&mctz->lock); |
bb4cc1a8 | 563 | mz = __mem_cgroup_largest_soft_limit_node(mctz); |
0a31bc97 | 564 | spin_unlock_irq(&mctz->lock); |
bb4cc1a8 AM |
565 | return mz; |
566 | } | |
567 | ||
11192d9c SB |
568 | /* |
569 | * memcg and lruvec stats flushing | |
570 | * | |
571 | * Many codepaths leading to stats update or read are performance sensitive and | |
572 | * adding stats flushing in such codepaths is not desirable. So, to optimize the | |
573 | * flushing the kernel does: | |
574 | * | |
575 | * 1) Periodically and asynchronously flush the stats every 2 seconds to not let | |
576 | * rstat update tree grow unbounded. | |
577 | * | |
578 | * 2) Flush the stats synchronously on reader side only when there are more than | |
579 | * (MEMCG_CHARGE_BATCH * nr_cpus) update events. Though this optimization | |
580 | * will let stats be out of sync by atmost (MEMCG_CHARGE_BATCH * nr_cpus) but | |
581 | * only for 2 seconds due to (1). | |
582 | */ | |
583 | static void flush_memcg_stats_dwork(struct work_struct *w); | |
584 | static DECLARE_DEFERRABLE_WORK(stats_flush_dwork, flush_memcg_stats_dwork); | |
585 | static DEFINE_SPINLOCK(stats_flush_lock); | |
586 | static DEFINE_PER_CPU(unsigned int, stats_updates); | |
587 | static atomic_t stats_flush_threshold = ATOMIC_INIT(0); | |
9b301615 SB |
588 | static u64 flush_next_time; |
589 | ||
590 | #define FLUSH_TIME (2UL*HZ) | |
11192d9c | 591 | |
be3e67b5 SAS |
592 | /* |
593 | * Accessors to ensure that preemption is disabled on PREEMPT_RT because it can | |
594 | * not rely on this as part of an acquired spinlock_t lock. These functions are | |
595 | * never used in hardirq context on PREEMPT_RT and therefore disabling preemtion | |
596 | * is sufficient. | |
597 | */ | |
598 | static void memcg_stats_lock(void) | |
599 | { | |
600 | #ifdef CONFIG_PREEMPT_RT | |
601 | preempt_disable(); | |
602 | #else | |
603 | VM_BUG_ON(!irqs_disabled()); | |
604 | #endif | |
605 | } | |
606 | ||
607 | static void __memcg_stats_lock(void) | |
608 | { | |
609 | #ifdef CONFIG_PREEMPT_RT | |
610 | preempt_disable(); | |
611 | #endif | |
612 | } | |
613 | ||
614 | static void memcg_stats_unlock(void) | |
615 | { | |
616 | #ifdef CONFIG_PREEMPT_RT | |
617 | preempt_enable(); | |
618 | #endif | |
619 | } | |
620 | ||
5b3be698 | 621 | static inline void memcg_rstat_updated(struct mem_cgroup *memcg, int val) |
11192d9c | 622 | { |
5b3be698 SB |
623 | unsigned int x; |
624 | ||
11192d9c | 625 | cgroup_rstat_updated(memcg->css.cgroup, smp_processor_id()); |
5b3be698 SB |
626 | |
627 | x = __this_cpu_add_return(stats_updates, abs(val)); | |
628 | if (x > MEMCG_CHARGE_BATCH) { | |
629 | atomic_add(x / MEMCG_CHARGE_BATCH, &stats_flush_threshold); | |
630 | __this_cpu_write(stats_updates, 0); | |
631 | } | |
11192d9c SB |
632 | } |
633 | ||
634 | static void __mem_cgroup_flush_stats(void) | |
635 | { | |
fd25a9e0 SB |
636 | unsigned long flag; |
637 | ||
638 | if (!spin_trylock_irqsave(&stats_flush_lock, flag)) | |
11192d9c SB |
639 | return; |
640 | ||
9b301615 | 641 | flush_next_time = jiffies_64 + 2*FLUSH_TIME; |
11192d9c SB |
642 | cgroup_rstat_flush_irqsafe(root_mem_cgroup->css.cgroup); |
643 | atomic_set(&stats_flush_threshold, 0); | |
fd25a9e0 | 644 | spin_unlock_irqrestore(&stats_flush_lock, flag); |
11192d9c SB |
645 | } |
646 | ||
647 | void mem_cgroup_flush_stats(void) | |
648 | { | |
649 | if (atomic_read(&stats_flush_threshold) > num_online_cpus()) | |
650 | __mem_cgroup_flush_stats(); | |
651 | } | |
652 | ||
9b301615 SB |
653 | void mem_cgroup_flush_stats_delayed(void) |
654 | { | |
655 | if (time_after64(jiffies_64, flush_next_time)) | |
656 | mem_cgroup_flush_stats(); | |
657 | } | |
658 | ||
11192d9c SB |
659 | static void flush_memcg_stats_dwork(struct work_struct *w) |
660 | { | |
5b3be698 | 661 | __mem_cgroup_flush_stats(); |
9b301615 | 662 | queue_delayed_work(system_unbound_wq, &stats_flush_dwork, FLUSH_TIME); |
11192d9c SB |
663 | } |
664 | ||
db9adbcb JW |
665 | /** |
666 | * __mod_memcg_state - update cgroup memory statistics | |
667 | * @memcg: the memory cgroup | |
668 | * @idx: the stat item - can be enum memcg_stat_item or enum node_stat_item | |
669 | * @val: delta to add to the counter, can be negative | |
670 | */ | |
671 | void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val) | |
672 | { | |
db9adbcb JW |
673 | if (mem_cgroup_disabled()) |
674 | return; | |
675 | ||
2d146aa3 | 676 | __this_cpu_add(memcg->vmstats_percpu->state[idx], val); |
5b3be698 | 677 | memcg_rstat_updated(memcg, val); |
db9adbcb JW |
678 | } |
679 | ||
2d146aa3 | 680 | /* idx can be of type enum memcg_stat_item or node_stat_item. */ |
a18e6e6e JW |
681 | static unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx) |
682 | { | |
683 | long x = 0; | |
684 | int cpu; | |
685 | ||
686 | for_each_possible_cpu(cpu) | |
2d146aa3 | 687 | x += per_cpu(memcg->vmstats_percpu->state[idx], cpu); |
a18e6e6e JW |
688 | #ifdef CONFIG_SMP |
689 | if (x < 0) | |
690 | x = 0; | |
691 | #endif | |
692 | return x; | |
693 | } | |
694 | ||
eedc4e5a RG |
695 | void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, |
696 | int val) | |
db9adbcb JW |
697 | { |
698 | struct mem_cgroup_per_node *pn; | |
42a30035 | 699 | struct mem_cgroup *memcg; |
db9adbcb | 700 | |
db9adbcb | 701 | pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec); |
42a30035 | 702 | memcg = pn->memcg; |
db9adbcb | 703 | |
be3e67b5 SAS |
704 | /* |
705 | * The caller from rmap relay on disabled preemption becase they never | |
706 | * update their counter from in-interrupt context. For these two | |
707 | * counters we check that the update is never performed from an | |
708 | * interrupt context while other caller need to have disabled interrupt. | |
709 | */ | |
710 | __memcg_stats_lock(); | |
711 | if (IS_ENABLED(CONFIG_DEBUG_VM) && !IS_ENABLED(CONFIG_PREEMPT_RT)) { | |
712 | switch (idx) { | |
713 | case NR_ANON_MAPPED: | |
714 | case NR_FILE_MAPPED: | |
715 | case NR_ANON_THPS: | |
716 | case NR_SHMEM_PMDMAPPED: | |
717 | case NR_FILE_PMDMAPPED: | |
718 | WARN_ON_ONCE(!in_task()); | |
719 | break; | |
720 | default: | |
721 | WARN_ON_ONCE(!irqs_disabled()); | |
722 | } | |
723 | } | |
724 | ||
db9adbcb | 725 | /* Update memcg */ |
11192d9c | 726 | __this_cpu_add(memcg->vmstats_percpu->state[idx], val); |
db9adbcb | 727 | |
b4c46484 | 728 | /* Update lruvec */ |
7e1c0d6f | 729 | __this_cpu_add(pn->lruvec_stats_percpu->state[idx], val); |
11192d9c | 730 | |
5b3be698 | 731 | memcg_rstat_updated(memcg, val); |
be3e67b5 | 732 | memcg_stats_unlock(); |
db9adbcb JW |
733 | } |
734 | ||
eedc4e5a RG |
735 | /** |
736 | * __mod_lruvec_state - update lruvec memory statistics | |
737 | * @lruvec: the lruvec | |
738 | * @idx: the stat item | |
739 | * @val: delta to add to the counter, can be negative | |
740 | * | |
741 | * The lruvec is the intersection of the NUMA node and a cgroup. This | |
742 | * function updates the all three counters that are affected by a | |
743 | * change of state at this level: per-node, per-cgroup, per-lruvec. | |
744 | */ | |
745 | void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, | |
746 | int val) | |
747 | { | |
748 | /* Update node */ | |
749 | __mod_node_page_state(lruvec_pgdat(lruvec), idx, val); | |
750 | ||
751 | /* Update memcg and lruvec */ | |
752 | if (!mem_cgroup_disabled()) | |
753 | __mod_memcg_lruvec_state(lruvec, idx, val); | |
754 | } | |
755 | ||
c47d5032 SB |
756 | void __mod_lruvec_page_state(struct page *page, enum node_stat_item idx, |
757 | int val) | |
758 | { | |
759 | struct page *head = compound_head(page); /* rmap on tail pages */ | |
b4e0b68f | 760 | struct mem_cgroup *memcg; |
c47d5032 SB |
761 | pg_data_t *pgdat = page_pgdat(page); |
762 | struct lruvec *lruvec; | |
763 | ||
b4e0b68f MS |
764 | rcu_read_lock(); |
765 | memcg = page_memcg(head); | |
c47d5032 | 766 | /* Untracked pages have no memcg, no lruvec. Update only the node */ |
d635a69d | 767 | if (!memcg) { |
b4e0b68f | 768 | rcu_read_unlock(); |
c47d5032 SB |
769 | __mod_node_page_state(pgdat, idx, val); |
770 | return; | |
771 | } | |
772 | ||
d635a69d | 773 | lruvec = mem_cgroup_lruvec(memcg, pgdat); |
c47d5032 | 774 | __mod_lruvec_state(lruvec, idx, val); |
b4e0b68f | 775 | rcu_read_unlock(); |
c47d5032 | 776 | } |
f0c0c115 | 777 | EXPORT_SYMBOL(__mod_lruvec_page_state); |
c47d5032 | 778 | |
da3ceeff | 779 | void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) |
ec9f0238 | 780 | { |
4f103c63 | 781 | pg_data_t *pgdat = page_pgdat(virt_to_page(p)); |
ec9f0238 RG |
782 | struct mem_cgroup *memcg; |
783 | struct lruvec *lruvec; | |
784 | ||
785 | rcu_read_lock(); | |
fc4db90f | 786 | memcg = mem_cgroup_from_slab_obj(p); |
ec9f0238 | 787 | |
8faeb1ff MS |
788 | /* |
789 | * Untracked pages have no memcg, no lruvec. Update only the | |
790 | * node. If we reparent the slab objects to the root memcg, | |
791 | * when we free the slab object, we need to update the per-memcg | |
792 | * vmstats to keep it correct for the root memcg. | |
793 | */ | |
794 | if (!memcg) { | |
ec9f0238 RG |
795 | __mod_node_page_state(pgdat, idx, val); |
796 | } else { | |
867e5e1d | 797 | lruvec = mem_cgroup_lruvec(memcg, pgdat); |
ec9f0238 RG |
798 | __mod_lruvec_state(lruvec, idx, val); |
799 | } | |
800 | rcu_read_unlock(); | |
801 | } | |
802 | ||
db9adbcb JW |
803 | /** |
804 | * __count_memcg_events - account VM events in a cgroup | |
805 | * @memcg: the memory cgroup | |
806 | * @idx: the event item | |
f0953a1b | 807 | * @count: the number of events that occurred |
db9adbcb JW |
808 | */ |
809 | void __count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx, | |
810 | unsigned long count) | |
811 | { | |
db9adbcb JW |
812 | if (mem_cgroup_disabled()) |
813 | return; | |
814 | ||
be3e67b5 | 815 | memcg_stats_lock(); |
2d146aa3 | 816 | __this_cpu_add(memcg->vmstats_percpu->events[idx], count); |
5b3be698 | 817 | memcg_rstat_updated(memcg, count); |
be3e67b5 | 818 | memcg_stats_unlock(); |
db9adbcb JW |
819 | } |
820 | ||
42a30035 | 821 | static unsigned long memcg_events(struct mem_cgroup *memcg, int event) |
e9f8974f | 822 | { |
2d146aa3 | 823 | return READ_ONCE(memcg->vmstats.events[event]); |
e9f8974f JW |
824 | } |
825 | ||
42a30035 JW |
826 | static unsigned long memcg_events_local(struct mem_cgroup *memcg, int event) |
827 | { | |
815744d7 JW |
828 | long x = 0; |
829 | int cpu; | |
830 | ||
831 | for_each_possible_cpu(cpu) | |
2d146aa3 | 832 | x += per_cpu(memcg->vmstats_percpu->events[event], cpu); |
815744d7 | 833 | return x; |
42a30035 JW |
834 | } |
835 | ||
c0ff4b85 | 836 | static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, |
3fba69a5 | 837 | int nr_pages) |
d52aa412 | 838 | { |
e401f176 KH |
839 | /* pagein of a big page is an event. So, ignore page size */ |
840 | if (nr_pages > 0) | |
c9019e9b | 841 | __count_memcg_events(memcg, PGPGIN, 1); |
3751d604 | 842 | else { |
c9019e9b | 843 | __count_memcg_events(memcg, PGPGOUT, 1); |
3751d604 KH |
844 | nr_pages = -nr_pages; /* for event */ |
845 | } | |
e401f176 | 846 | |
871789d4 | 847 | __this_cpu_add(memcg->vmstats_percpu->nr_page_events, nr_pages); |
6d12e2d8 KH |
848 | } |
849 | ||
f53d7ce3 JW |
850 | static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg, |
851 | enum mem_cgroup_events_target target) | |
7a159cc9 JW |
852 | { |
853 | unsigned long val, next; | |
854 | ||
871789d4 CD |
855 | val = __this_cpu_read(memcg->vmstats_percpu->nr_page_events); |
856 | next = __this_cpu_read(memcg->vmstats_percpu->targets[target]); | |
7a159cc9 | 857 | /* from time_after() in jiffies.h */ |
6a1a8b80 | 858 | if ((long)(next - val) < 0) { |
f53d7ce3 JW |
859 | switch (target) { |
860 | case MEM_CGROUP_TARGET_THRESH: | |
861 | next = val + THRESHOLDS_EVENTS_TARGET; | |
862 | break; | |
bb4cc1a8 AM |
863 | case MEM_CGROUP_TARGET_SOFTLIMIT: |
864 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
865 | break; | |
f53d7ce3 JW |
866 | default: |
867 | break; | |
868 | } | |
871789d4 | 869 | __this_cpu_write(memcg->vmstats_percpu->targets[target], next); |
f53d7ce3 | 870 | return true; |
7a159cc9 | 871 | } |
f53d7ce3 | 872 | return false; |
d2265e6f KH |
873 | } |
874 | ||
875 | /* | |
876 | * Check events in order. | |
877 | * | |
878 | */ | |
8e88bd2d | 879 | static void memcg_check_events(struct mem_cgroup *memcg, int nid) |
d2265e6f | 880 | { |
2343e88d SAS |
881 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) |
882 | return; | |
883 | ||
d2265e6f | 884 | /* threshold event is triggered in finer grain than soft limit */ |
f53d7ce3 JW |
885 | if (unlikely(mem_cgroup_event_ratelimit(memcg, |
886 | MEM_CGROUP_TARGET_THRESH))) { | |
bb4cc1a8 | 887 | bool do_softlimit; |
f53d7ce3 | 888 | |
bb4cc1a8 AM |
889 | do_softlimit = mem_cgroup_event_ratelimit(memcg, |
890 | MEM_CGROUP_TARGET_SOFTLIMIT); | |
c0ff4b85 | 891 | mem_cgroup_threshold(memcg); |
bb4cc1a8 | 892 | if (unlikely(do_softlimit)) |
8e88bd2d | 893 | mem_cgroup_update_tree(memcg, nid); |
0a31bc97 | 894 | } |
d2265e6f KH |
895 | } |
896 | ||
cf475ad2 | 897 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 898 | { |
31a78f23 BS |
899 | /* |
900 | * mm_update_next_owner() may clear mm->owner to NULL | |
901 | * if it races with swapoff, page migration, etc. | |
902 | * So this can be called with p == NULL. | |
903 | */ | |
904 | if (unlikely(!p)) | |
905 | return NULL; | |
906 | ||
073219e9 | 907 | return mem_cgroup_from_css(task_css(p, memory_cgrp_id)); |
78fb7466 | 908 | } |
33398cf2 | 909 | EXPORT_SYMBOL(mem_cgroup_from_task); |
78fb7466 | 910 | |
04f94e3f DS |
911 | static __always_inline struct mem_cgroup *active_memcg(void) |
912 | { | |
55a68c82 | 913 | if (!in_task()) |
04f94e3f DS |
914 | return this_cpu_read(int_active_memcg); |
915 | else | |
916 | return current->active_memcg; | |
917 | } | |
918 | ||
d46eb14b SB |
919 | /** |
920 | * get_mem_cgroup_from_mm: Obtain a reference on given mm_struct's memcg. | |
921 | * @mm: mm from which memcg should be extracted. It can be NULL. | |
922 | * | |
04f94e3f DS |
923 | * Obtain a reference on mm->memcg and returns it if successful. If mm |
924 | * is NULL, then the memcg is chosen as follows: | |
925 | * 1) The active memcg, if set. | |
926 | * 2) current->mm->memcg, if available | |
927 | * 3) root memcg | |
928 | * If mem_cgroup is disabled, NULL is returned. | |
d46eb14b SB |
929 | */ |
930 | struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm) | |
54595fe2 | 931 | { |
d46eb14b SB |
932 | struct mem_cgroup *memcg; |
933 | ||
934 | if (mem_cgroup_disabled()) | |
935 | return NULL; | |
0b7f569e | 936 | |
2884b6b7 MS |
937 | /* |
938 | * Page cache insertions can happen without an | |
939 | * actual mm context, e.g. during disk probing | |
940 | * on boot, loopback IO, acct() writes etc. | |
941 | * | |
942 | * No need to css_get on root memcg as the reference | |
943 | * counting is disabled on the root level in the | |
944 | * cgroup core. See CSS_NO_REF. | |
945 | */ | |
04f94e3f DS |
946 | if (unlikely(!mm)) { |
947 | memcg = active_memcg(); | |
948 | if (unlikely(memcg)) { | |
949 | /* remote memcg must hold a ref */ | |
950 | css_get(&memcg->css); | |
951 | return memcg; | |
952 | } | |
953 | mm = current->mm; | |
954 | if (unlikely(!mm)) | |
955 | return root_mem_cgroup; | |
956 | } | |
2884b6b7 | 957 | |
54595fe2 KH |
958 | rcu_read_lock(); |
959 | do { | |
2884b6b7 MS |
960 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); |
961 | if (unlikely(!memcg)) | |
df381975 | 962 | memcg = root_mem_cgroup; |
00d484f3 | 963 | } while (!css_tryget(&memcg->css)); |
54595fe2 | 964 | rcu_read_unlock(); |
c0ff4b85 | 965 | return memcg; |
54595fe2 | 966 | } |
d46eb14b SB |
967 | EXPORT_SYMBOL(get_mem_cgroup_from_mm); |
968 | ||
4127c650 RG |
969 | static __always_inline bool memcg_kmem_bypass(void) |
970 | { | |
971 | /* Allow remote memcg charging from any context. */ | |
972 | if (unlikely(active_memcg())) | |
973 | return false; | |
974 | ||
975 | /* Memcg to charge can't be determined. */ | |
6126891c | 976 | if (!in_task() || !current->mm || (current->flags & PF_KTHREAD)) |
4127c650 RG |
977 | return true; |
978 | ||
979 | return false; | |
980 | } | |
981 | ||
5660048c JW |
982 | /** |
983 | * mem_cgroup_iter - iterate over memory cgroup hierarchy | |
984 | * @root: hierarchy root | |
985 | * @prev: previously returned memcg, NULL on first invocation | |
986 | * @reclaim: cookie for shared reclaim walks, NULL for full walks | |
987 | * | |
988 | * Returns references to children of the hierarchy below @root, or | |
989 | * @root itself, or %NULL after a full round-trip. | |
990 | * | |
991 | * Caller must pass the return value in @prev on subsequent | |
992 | * invocations for reference counting, or use mem_cgroup_iter_break() | |
993 | * to cancel a hierarchy walk before the round-trip is complete. | |
994 | * | |
05bdc520 ML |
995 | * Reclaimers can specify a node in @reclaim to divide up the memcgs |
996 | * in the hierarchy among all concurrent reclaimers operating on the | |
997 | * same node. | |
5660048c | 998 | */ |
694fbc0f | 999 | struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, |
5660048c | 1000 | struct mem_cgroup *prev, |
694fbc0f | 1001 | struct mem_cgroup_reclaim_cookie *reclaim) |
14067bb3 | 1002 | { |
3f649ab7 | 1003 | struct mem_cgroup_reclaim_iter *iter; |
5ac8fb31 | 1004 | struct cgroup_subsys_state *css = NULL; |
9f3a0d09 | 1005 | struct mem_cgroup *memcg = NULL; |
5ac8fb31 | 1006 | struct mem_cgroup *pos = NULL; |
711d3d2c | 1007 | |
694fbc0f AM |
1008 | if (mem_cgroup_disabled()) |
1009 | return NULL; | |
5660048c | 1010 | |
9f3a0d09 JW |
1011 | if (!root) |
1012 | root = root_mem_cgroup; | |
7d74b06f | 1013 | |
542f85f9 | 1014 | rcu_read_lock(); |
5f578161 | 1015 | |
5ac8fb31 | 1016 | if (reclaim) { |
ef8f2327 | 1017 | struct mem_cgroup_per_node *mz; |
5ac8fb31 | 1018 | |
a3747b53 | 1019 | mz = root->nodeinfo[reclaim->pgdat->node_id]; |
9da83f3f | 1020 | iter = &mz->iter; |
5ac8fb31 | 1021 | |
a9320aae WY |
1022 | /* |
1023 | * On start, join the current reclaim iteration cycle. | |
1024 | * Exit when a concurrent walker completes it. | |
1025 | */ | |
1026 | if (!prev) | |
1027 | reclaim->generation = iter->generation; | |
1028 | else if (reclaim->generation != iter->generation) | |
5ac8fb31 JW |
1029 | goto out_unlock; |
1030 | ||
6df38689 | 1031 | while (1) { |
4db0c3c2 | 1032 | pos = READ_ONCE(iter->position); |
6df38689 VD |
1033 | if (!pos || css_tryget(&pos->css)) |
1034 | break; | |
5ac8fb31 | 1035 | /* |
6df38689 VD |
1036 | * css reference reached zero, so iter->position will |
1037 | * be cleared by ->css_released. However, we should not | |
1038 | * rely on this happening soon, because ->css_released | |
1039 | * is called from a work queue, and by busy-waiting we | |
1040 | * might block it. So we clear iter->position right | |
1041 | * away. | |
5ac8fb31 | 1042 | */ |
6df38689 VD |
1043 | (void)cmpxchg(&iter->position, pos, NULL); |
1044 | } | |
89d8330c WY |
1045 | } else if (prev) { |
1046 | pos = prev; | |
5ac8fb31 JW |
1047 | } |
1048 | ||
1049 | if (pos) | |
1050 | css = &pos->css; | |
1051 | ||
1052 | for (;;) { | |
1053 | css = css_next_descendant_pre(css, &root->css); | |
1054 | if (!css) { | |
1055 | /* | |
1056 | * Reclaimers share the hierarchy walk, and a | |
1057 | * new one might jump in right at the end of | |
1058 | * the hierarchy - make sure they see at least | |
1059 | * one group and restart from the beginning. | |
1060 | */ | |
1061 | if (!prev) | |
1062 | continue; | |
1063 | break; | |
527a5ec9 | 1064 | } |
7d74b06f | 1065 | |
5ac8fb31 JW |
1066 | /* |
1067 | * Verify the css and acquire a reference. The root | |
1068 | * is provided by the caller, so we know it's alive | |
1069 | * and kicking, and don't take an extra reference. | |
1070 | */ | |
41555dad WY |
1071 | if (css == &root->css || css_tryget(css)) { |
1072 | memcg = mem_cgroup_from_css(css); | |
0b8f73e1 | 1073 | break; |
41555dad | 1074 | } |
9f3a0d09 | 1075 | } |
5ac8fb31 JW |
1076 | |
1077 | if (reclaim) { | |
5ac8fb31 | 1078 | /* |
6df38689 VD |
1079 | * The position could have already been updated by a competing |
1080 | * thread, so check that the value hasn't changed since we read | |
1081 | * it to avoid reclaiming from the same cgroup twice. | |
5ac8fb31 | 1082 | */ |
6df38689 VD |
1083 | (void)cmpxchg(&iter->position, pos, memcg); |
1084 | ||
5ac8fb31 JW |
1085 | if (pos) |
1086 | css_put(&pos->css); | |
1087 | ||
1088 | if (!memcg) | |
1089 | iter->generation++; | |
9f3a0d09 | 1090 | } |
5ac8fb31 | 1091 | |
542f85f9 MH |
1092 | out_unlock: |
1093 | rcu_read_unlock(); | |
c40046f3 MH |
1094 | if (prev && prev != root) |
1095 | css_put(&prev->css); | |
1096 | ||
9f3a0d09 | 1097 | return memcg; |
14067bb3 | 1098 | } |
7d74b06f | 1099 | |
5660048c JW |
1100 | /** |
1101 | * mem_cgroup_iter_break - abort a hierarchy walk prematurely | |
1102 | * @root: hierarchy root | |
1103 | * @prev: last visited hierarchy member as returned by mem_cgroup_iter() | |
1104 | */ | |
1105 | void mem_cgroup_iter_break(struct mem_cgroup *root, | |
1106 | struct mem_cgroup *prev) | |
9f3a0d09 JW |
1107 | { |
1108 | if (!root) | |
1109 | root = root_mem_cgroup; | |
1110 | if (prev && prev != root) | |
1111 | css_put(&prev->css); | |
1112 | } | |
7d74b06f | 1113 | |
54a83d6b MC |
1114 | static void __invalidate_reclaim_iterators(struct mem_cgroup *from, |
1115 | struct mem_cgroup *dead_memcg) | |
6df38689 | 1116 | { |
6df38689 | 1117 | struct mem_cgroup_reclaim_iter *iter; |
ef8f2327 MG |
1118 | struct mem_cgroup_per_node *mz; |
1119 | int nid; | |
6df38689 | 1120 | |
54a83d6b | 1121 | for_each_node(nid) { |
a3747b53 | 1122 | mz = from->nodeinfo[nid]; |
9da83f3f YS |
1123 | iter = &mz->iter; |
1124 | cmpxchg(&iter->position, dead_memcg, NULL); | |
6df38689 VD |
1125 | } |
1126 | } | |
1127 | ||
54a83d6b MC |
1128 | static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg) |
1129 | { | |
1130 | struct mem_cgroup *memcg = dead_memcg; | |
1131 | struct mem_cgroup *last; | |
1132 | ||
1133 | do { | |
1134 | __invalidate_reclaim_iterators(memcg, dead_memcg); | |
1135 | last = memcg; | |
1136 | } while ((memcg = parent_mem_cgroup(memcg))); | |
1137 | ||
1138 | /* | |
1139 | * When cgruop1 non-hierarchy mode is used, | |
1140 | * parent_mem_cgroup() does not walk all the way up to the | |
1141 | * cgroup root (root_mem_cgroup). So we have to handle | |
1142 | * dead_memcg from cgroup root separately. | |
1143 | */ | |
1144 | if (last != root_mem_cgroup) | |
1145 | __invalidate_reclaim_iterators(root_mem_cgroup, | |
1146 | dead_memcg); | |
1147 | } | |
1148 | ||
7c5f64f8 VD |
1149 | /** |
1150 | * mem_cgroup_scan_tasks - iterate over tasks of a memory cgroup hierarchy | |
1151 | * @memcg: hierarchy root | |
1152 | * @fn: function to call for each task | |
1153 | * @arg: argument passed to @fn | |
1154 | * | |
1155 | * This function iterates over tasks attached to @memcg or to any of its | |
1156 | * descendants and calls @fn for each task. If @fn returns a non-zero | |
1157 | * value, the function breaks the iteration loop and returns the value. | |
1158 | * Otherwise, it will iterate over all tasks and return 0. | |
1159 | * | |
1160 | * This function must not be called for the root memory cgroup. | |
1161 | */ | |
1162 | int mem_cgroup_scan_tasks(struct mem_cgroup *memcg, | |
1163 | int (*fn)(struct task_struct *, void *), void *arg) | |
1164 | { | |
1165 | struct mem_cgroup *iter; | |
1166 | int ret = 0; | |
1167 | ||
1168 | BUG_ON(memcg == root_mem_cgroup); | |
1169 | ||
1170 | for_each_mem_cgroup_tree(iter, memcg) { | |
1171 | struct css_task_iter it; | |
1172 | struct task_struct *task; | |
1173 | ||
f168a9a5 | 1174 | css_task_iter_start(&iter->css, CSS_TASK_ITER_PROCS, &it); |
7c5f64f8 VD |
1175 | while (!ret && (task = css_task_iter_next(&it))) |
1176 | ret = fn(task, arg); | |
1177 | css_task_iter_end(&it); | |
1178 | if (ret) { | |
1179 | mem_cgroup_iter_break(memcg, iter); | |
1180 | break; | |
1181 | } | |
1182 | } | |
1183 | return ret; | |
1184 | } | |
1185 | ||
6168d0da | 1186 | #ifdef CONFIG_DEBUG_VM |
e809c3fe | 1187 | void lruvec_memcg_debug(struct lruvec *lruvec, struct folio *folio) |
6168d0da AS |
1188 | { |
1189 | struct mem_cgroup *memcg; | |
1190 | ||
1191 | if (mem_cgroup_disabled()) | |
1192 | return; | |
1193 | ||
e809c3fe | 1194 | memcg = folio_memcg(folio); |
6168d0da AS |
1195 | |
1196 | if (!memcg) | |
e809c3fe | 1197 | VM_BUG_ON_FOLIO(lruvec_memcg(lruvec) != root_mem_cgroup, folio); |
6168d0da | 1198 | else |
e809c3fe | 1199 | VM_BUG_ON_FOLIO(lruvec_memcg(lruvec) != memcg, folio); |
6168d0da AS |
1200 | } |
1201 | #endif | |
1202 | ||
6168d0da | 1203 | /** |
e809c3fe MWO |
1204 | * folio_lruvec_lock - Lock the lruvec for a folio. |
1205 | * @folio: Pointer to the folio. | |
6168d0da | 1206 | * |
d7e3aba5 | 1207 | * These functions are safe to use under any of the following conditions: |
e809c3fe MWO |
1208 | * - folio locked |
1209 | * - folio_test_lru false | |
1210 | * - folio_memcg_lock() | |
1211 | * - folio frozen (refcount of 0) | |
1212 | * | |
1213 | * Return: The lruvec this folio is on with its lock held. | |
6168d0da | 1214 | */ |
e809c3fe | 1215 | struct lruvec *folio_lruvec_lock(struct folio *folio) |
6168d0da | 1216 | { |
e809c3fe | 1217 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1218 | |
6168d0da | 1219 | spin_lock(&lruvec->lru_lock); |
e809c3fe | 1220 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1221 | |
1222 | return lruvec; | |
1223 | } | |
1224 | ||
e809c3fe MWO |
1225 | /** |
1226 | * folio_lruvec_lock_irq - Lock the lruvec for a folio. | |
1227 | * @folio: Pointer to the folio. | |
1228 | * | |
1229 | * These functions are safe to use under any of the following conditions: | |
1230 | * - folio locked | |
1231 | * - folio_test_lru false | |
1232 | * - folio_memcg_lock() | |
1233 | * - folio frozen (refcount of 0) | |
1234 | * | |
1235 | * Return: The lruvec this folio is on with its lock held and interrupts | |
1236 | * disabled. | |
1237 | */ | |
1238 | struct lruvec *folio_lruvec_lock_irq(struct folio *folio) | |
6168d0da | 1239 | { |
e809c3fe | 1240 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1241 | |
6168d0da | 1242 | spin_lock_irq(&lruvec->lru_lock); |
e809c3fe | 1243 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1244 | |
1245 | return lruvec; | |
1246 | } | |
1247 | ||
e809c3fe MWO |
1248 | /** |
1249 | * folio_lruvec_lock_irqsave - Lock the lruvec for a folio. | |
1250 | * @folio: Pointer to the folio. | |
1251 | * @flags: Pointer to irqsave flags. | |
1252 | * | |
1253 | * These functions are safe to use under any of the following conditions: | |
1254 | * - folio locked | |
1255 | * - folio_test_lru false | |
1256 | * - folio_memcg_lock() | |
1257 | * - folio frozen (refcount of 0) | |
1258 | * | |
1259 | * Return: The lruvec this folio is on with its lock held and interrupts | |
1260 | * disabled. | |
1261 | */ | |
1262 | struct lruvec *folio_lruvec_lock_irqsave(struct folio *folio, | |
1263 | unsigned long *flags) | |
6168d0da | 1264 | { |
e809c3fe | 1265 | struct lruvec *lruvec = folio_lruvec(folio); |
6168d0da | 1266 | |
6168d0da | 1267 | spin_lock_irqsave(&lruvec->lru_lock, *flags); |
e809c3fe | 1268 | lruvec_memcg_debug(lruvec, folio); |
6168d0da AS |
1269 | |
1270 | return lruvec; | |
1271 | } | |
1272 | ||
925b7673 | 1273 | /** |
fa9add64 HD |
1274 | * mem_cgroup_update_lru_size - account for adding or removing an lru page |
1275 | * @lruvec: mem_cgroup per zone lru vector | |
1276 | * @lru: index of lru list the page is sitting on | |
b4536f0c | 1277 | * @zid: zone id of the accounted pages |
fa9add64 | 1278 | * @nr_pages: positive when adding or negative when removing |
925b7673 | 1279 | * |
ca707239 | 1280 | * This function must be called under lru_lock, just before a page is added |
07ca7606 | 1281 | * to or just after a page is removed from an lru list. |
3f58a829 | 1282 | */ |
fa9add64 | 1283 | void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, |
b4536f0c | 1284 | int zid, int nr_pages) |
3f58a829 | 1285 | { |
ef8f2327 | 1286 | struct mem_cgroup_per_node *mz; |
fa9add64 | 1287 | unsigned long *lru_size; |
ca707239 | 1288 | long size; |
3f58a829 MK |
1289 | |
1290 | if (mem_cgroup_disabled()) | |
1291 | return; | |
1292 | ||
ef8f2327 | 1293 | mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); |
b4536f0c | 1294 | lru_size = &mz->lru_zone_size[zid][lru]; |
ca707239 HD |
1295 | |
1296 | if (nr_pages < 0) | |
1297 | *lru_size += nr_pages; | |
1298 | ||
1299 | size = *lru_size; | |
b4536f0c MH |
1300 | if (WARN_ONCE(size < 0, |
1301 | "%s(%p, %d, %d): lru_size %ld\n", | |
1302 | __func__, lruvec, lru, nr_pages, size)) { | |
ca707239 HD |
1303 | VM_BUG_ON(1); |
1304 | *lru_size = 0; | |
1305 | } | |
1306 | ||
1307 | if (nr_pages > 0) | |
1308 | *lru_size += nr_pages; | |
08e552c6 | 1309 | } |
544122e5 | 1310 | |
19942822 | 1311 | /** |
9d11ea9f | 1312 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
dad7557e | 1313 | * @memcg: the memory cgroup |
19942822 | 1314 | * |
9d11ea9f | 1315 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1316 | * pages. |
19942822 | 1317 | */ |
c0ff4b85 | 1318 | static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) |
19942822 | 1319 | { |
3e32cb2e JW |
1320 | unsigned long margin = 0; |
1321 | unsigned long count; | |
1322 | unsigned long limit; | |
9d11ea9f | 1323 | |
3e32cb2e | 1324 | count = page_counter_read(&memcg->memory); |
bbec2e15 | 1325 | limit = READ_ONCE(memcg->memory.max); |
3e32cb2e JW |
1326 | if (count < limit) |
1327 | margin = limit - count; | |
1328 | ||
7941d214 | 1329 | if (do_memsw_account()) { |
3e32cb2e | 1330 | count = page_counter_read(&memcg->memsw); |
bbec2e15 | 1331 | limit = READ_ONCE(memcg->memsw.max); |
1c4448ed | 1332 | if (count < limit) |
3e32cb2e | 1333 | margin = min(margin, limit - count); |
cbedbac3 LR |
1334 | else |
1335 | margin = 0; | |
3e32cb2e JW |
1336 | } |
1337 | ||
1338 | return margin; | |
19942822 JW |
1339 | } |
1340 | ||
32047e2a | 1341 | /* |
bdcbb659 | 1342 | * A routine for checking "mem" is under move_account() or not. |
32047e2a | 1343 | * |
bdcbb659 QH |
1344 | * Checking a cgroup is mc.from or mc.to or under hierarchy of |
1345 | * moving cgroups. This is for waiting at high-memory pressure | |
1346 | * caused by "move". | |
32047e2a | 1347 | */ |
c0ff4b85 | 1348 | static bool mem_cgroup_under_move(struct mem_cgroup *memcg) |
4b534334 | 1349 | { |
2bd9bb20 KH |
1350 | struct mem_cgroup *from; |
1351 | struct mem_cgroup *to; | |
4b534334 | 1352 | bool ret = false; |
2bd9bb20 KH |
1353 | /* |
1354 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1355 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1356 | */ | |
1357 | spin_lock(&mc.lock); | |
1358 | from = mc.from; | |
1359 | to = mc.to; | |
1360 | if (!from) | |
1361 | goto unlock; | |
3e92041d | 1362 | |
2314b42d JW |
1363 | ret = mem_cgroup_is_descendant(from, memcg) || |
1364 | mem_cgroup_is_descendant(to, memcg); | |
2bd9bb20 KH |
1365 | unlock: |
1366 | spin_unlock(&mc.lock); | |
4b534334 KH |
1367 | return ret; |
1368 | } | |
1369 | ||
c0ff4b85 | 1370 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) |
4b534334 KH |
1371 | { |
1372 | if (mc.moving_task && current != mc.moving_task) { | |
c0ff4b85 | 1373 | if (mem_cgroup_under_move(memcg)) { |
4b534334 KH |
1374 | DEFINE_WAIT(wait); |
1375 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1376 | /* moving charge context might have finished. */ | |
1377 | if (mc.moving_task) | |
1378 | schedule(); | |
1379 | finish_wait(&mc.waitq, &wait); | |
1380 | return true; | |
1381 | } | |
1382 | } | |
1383 | return false; | |
1384 | } | |
1385 | ||
5f9a4f4a MS |
1386 | struct memory_stat { |
1387 | const char *name; | |
5f9a4f4a MS |
1388 | unsigned int idx; |
1389 | }; | |
1390 | ||
57b2847d | 1391 | static const struct memory_stat memory_stats[] = { |
fff66b79 MS |
1392 | { "anon", NR_ANON_MAPPED }, |
1393 | { "file", NR_FILE_PAGES }, | |
a8c49af3 | 1394 | { "kernel", MEMCG_KMEM }, |
fff66b79 MS |
1395 | { "kernel_stack", NR_KERNEL_STACK_KB }, |
1396 | { "pagetables", NR_PAGETABLE }, | |
1397 | { "percpu", MEMCG_PERCPU_B }, | |
1398 | { "sock", MEMCG_SOCK }, | |
4e5aa1f4 | 1399 | { "vmalloc", MEMCG_VMALLOC }, |
fff66b79 | 1400 | { "shmem", NR_SHMEM }, |
f4840ccf JW |
1401 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
1402 | { "zswap", MEMCG_ZSWAP_B }, | |
1403 | { "zswapped", MEMCG_ZSWAPPED }, | |
1404 | #endif | |
fff66b79 MS |
1405 | { "file_mapped", NR_FILE_MAPPED }, |
1406 | { "file_dirty", NR_FILE_DIRTY }, | |
1407 | { "file_writeback", NR_WRITEBACK }, | |
b6038942 SB |
1408 | #ifdef CONFIG_SWAP |
1409 | { "swapcached", NR_SWAPCACHE }, | |
1410 | #endif | |
5f9a4f4a | 1411 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
fff66b79 MS |
1412 | { "anon_thp", NR_ANON_THPS }, |
1413 | { "file_thp", NR_FILE_THPS }, | |
1414 | { "shmem_thp", NR_SHMEM_THPS }, | |
5f9a4f4a | 1415 | #endif |
fff66b79 MS |
1416 | { "inactive_anon", NR_INACTIVE_ANON }, |
1417 | { "active_anon", NR_ACTIVE_ANON }, | |
1418 | { "inactive_file", NR_INACTIVE_FILE }, | |
1419 | { "active_file", NR_ACTIVE_FILE }, | |
1420 | { "unevictable", NR_UNEVICTABLE }, | |
1421 | { "slab_reclaimable", NR_SLAB_RECLAIMABLE_B }, | |
1422 | { "slab_unreclaimable", NR_SLAB_UNRECLAIMABLE_B }, | |
5f9a4f4a MS |
1423 | |
1424 | /* The memory events */ | |
fff66b79 MS |
1425 | { "workingset_refault_anon", WORKINGSET_REFAULT_ANON }, |
1426 | { "workingset_refault_file", WORKINGSET_REFAULT_FILE }, | |
1427 | { "workingset_activate_anon", WORKINGSET_ACTIVATE_ANON }, | |
1428 | { "workingset_activate_file", WORKINGSET_ACTIVATE_FILE }, | |
1429 | { "workingset_restore_anon", WORKINGSET_RESTORE_ANON }, | |
1430 | { "workingset_restore_file", WORKINGSET_RESTORE_FILE }, | |
1431 | { "workingset_nodereclaim", WORKINGSET_NODERECLAIM }, | |
5f9a4f4a MS |
1432 | }; |
1433 | ||
fff66b79 MS |
1434 | /* Translate stat items to the correct unit for memory.stat output */ |
1435 | static int memcg_page_state_unit(int item) | |
1436 | { | |
1437 | switch (item) { | |
1438 | case MEMCG_PERCPU_B: | |
f4840ccf | 1439 | case MEMCG_ZSWAP_B: |
fff66b79 MS |
1440 | case NR_SLAB_RECLAIMABLE_B: |
1441 | case NR_SLAB_UNRECLAIMABLE_B: | |
1442 | case WORKINGSET_REFAULT_ANON: | |
1443 | case WORKINGSET_REFAULT_FILE: | |
1444 | case WORKINGSET_ACTIVATE_ANON: | |
1445 | case WORKINGSET_ACTIVATE_FILE: | |
1446 | case WORKINGSET_RESTORE_ANON: | |
1447 | case WORKINGSET_RESTORE_FILE: | |
1448 | case WORKINGSET_NODERECLAIM: | |
1449 | return 1; | |
1450 | case NR_KERNEL_STACK_KB: | |
1451 | return SZ_1K; | |
1452 | default: | |
1453 | return PAGE_SIZE; | |
1454 | } | |
1455 | } | |
1456 | ||
1457 | static inline unsigned long memcg_page_state_output(struct mem_cgroup *memcg, | |
1458 | int item) | |
1459 | { | |
1460 | return memcg_page_state(memcg, item) * memcg_page_state_unit(item); | |
1461 | } | |
1462 | ||
673520f8 QZ |
1463 | /* Subset of vm_event_item to report for memcg event stats */ |
1464 | static const unsigned int memcg_vm_event_stat[] = { | |
1465 | PGSCAN_KSWAPD, | |
1466 | PGSCAN_DIRECT, | |
1467 | PGSTEAL_KSWAPD, | |
1468 | PGSTEAL_DIRECT, | |
1469 | PGFAULT, | |
1470 | PGMAJFAULT, | |
1471 | PGREFILL, | |
1472 | PGACTIVATE, | |
1473 | PGDEACTIVATE, | |
1474 | PGLAZYFREE, | |
1475 | PGLAZYFREED, | |
1476 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) | |
1477 | ZSWPIN, | |
1478 | ZSWPOUT, | |
1479 | #endif | |
1480 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
1481 | THP_FAULT_ALLOC, | |
1482 | THP_COLLAPSE_ALLOC, | |
1483 | #endif | |
1484 | }; | |
1485 | ||
c8713d0b JW |
1486 | static char *memory_stat_format(struct mem_cgroup *memcg) |
1487 | { | |
1488 | struct seq_buf s; | |
1489 | int i; | |
71cd3113 | 1490 | |
c8713d0b JW |
1491 | seq_buf_init(&s, kmalloc(PAGE_SIZE, GFP_KERNEL), PAGE_SIZE); |
1492 | if (!s.buffer) | |
1493 | return NULL; | |
1494 | ||
1495 | /* | |
1496 | * Provide statistics on the state of the memory subsystem as | |
1497 | * well as cumulative event counters that show past behavior. | |
1498 | * | |
1499 | * This list is ordered following a combination of these gradients: | |
1500 | * 1) generic big picture -> specifics and details | |
1501 | * 2) reflecting userspace activity -> reflecting kernel heuristics | |
1502 | * | |
1503 | * Current memory state: | |
1504 | */ | |
fd25a9e0 | 1505 | mem_cgroup_flush_stats(); |
c8713d0b | 1506 | |
5f9a4f4a MS |
1507 | for (i = 0; i < ARRAY_SIZE(memory_stats); i++) { |
1508 | u64 size; | |
c8713d0b | 1509 | |
fff66b79 | 1510 | size = memcg_page_state_output(memcg, memory_stats[i].idx); |
5f9a4f4a | 1511 | seq_buf_printf(&s, "%s %llu\n", memory_stats[i].name, size); |
c8713d0b | 1512 | |
5f9a4f4a | 1513 | if (unlikely(memory_stats[i].idx == NR_SLAB_UNRECLAIMABLE_B)) { |
fff66b79 MS |
1514 | size += memcg_page_state_output(memcg, |
1515 | NR_SLAB_RECLAIMABLE_B); | |
5f9a4f4a MS |
1516 | seq_buf_printf(&s, "slab %llu\n", size); |
1517 | } | |
1518 | } | |
c8713d0b JW |
1519 | |
1520 | /* Accumulated memory events */ | |
c8713d0b JW |
1521 | seq_buf_printf(&s, "pgscan %lu\n", |
1522 | memcg_events(memcg, PGSCAN_KSWAPD) + | |
1523 | memcg_events(memcg, PGSCAN_DIRECT)); | |
1524 | seq_buf_printf(&s, "pgsteal %lu\n", | |
1525 | memcg_events(memcg, PGSTEAL_KSWAPD) + | |
1526 | memcg_events(memcg, PGSTEAL_DIRECT)); | |
c8713d0b | 1527 | |
673520f8 QZ |
1528 | for (i = 0; i < ARRAY_SIZE(memcg_vm_event_stat); i++) |
1529 | seq_buf_printf(&s, "%s %lu\n", | |
1530 | vm_event_name(memcg_vm_event_stat[i]), | |
1531 | memcg_events(memcg, memcg_vm_event_stat[i])); | |
c8713d0b JW |
1532 | |
1533 | /* The above should easily fit into one page */ | |
1534 | WARN_ON_ONCE(seq_buf_has_overflowed(&s)); | |
1535 | ||
1536 | return s.buffer; | |
1537 | } | |
71cd3113 | 1538 | |
58cf188e | 1539 | #define K(x) ((x) << (PAGE_SHIFT-10)) |
e222432b | 1540 | /** |
f0c867d9 | 1541 | * mem_cgroup_print_oom_context: Print OOM information relevant to |
1542 | * memory controller. | |
e222432b BS |
1543 | * @memcg: The memory cgroup that went over limit |
1544 | * @p: Task that is going to be killed | |
1545 | * | |
1546 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1547 | * enabled | |
1548 | */ | |
f0c867d9 | 1549 | void mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p) |
e222432b | 1550 | { |
e222432b BS |
1551 | rcu_read_lock(); |
1552 | ||
f0c867d9 | 1553 | if (memcg) { |
1554 | pr_cont(",oom_memcg="); | |
1555 | pr_cont_cgroup_path(memcg->css.cgroup); | |
1556 | } else | |
1557 | pr_cont(",global_oom"); | |
2415b9f5 | 1558 | if (p) { |
f0c867d9 | 1559 | pr_cont(",task_memcg="); |
2415b9f5 | 1560 | pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id)); |
2415b9f5 | 1561 | } |
e222432b | 1562 | rcu_read_unlock(); |
f0c867d9 | 1563 | } |
1564 | ||
1565 | /** | |
1566 | * mem_cgroup_print_oom_meminfo: Print OOM memory information relevant to | |
1567 | * memory controller. | |
1568 | * @memcg: The memory cgroup that went over limit | |
1569 | */ | |
1570 | void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg) | |
1571 | { | |
c8713d0b | 1572 | char *buf; |
e222432b | 1573 | |
3e32cb2e JW |
1574 | pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n", |
1575 | K((u64)page_counter_read(&memcg->memory)), | |
15b42562 | 1576 | K((u64)READ_ONCE(memcg->memory.max)), memcg->memory.failcnt); |
c8713d0b JW |
1577 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
1578 | pr_info("swap: usage %llukB, limit %llukB, failcnt %lu\n", | |
1579 | K((u64)page_counter_read(&memcg->swap)), | |
32d087cd | 1580 | K((u64)READ_ONCE(memcg->swap.max)), memcg->swap.failcnt); |
c8713d0b JW |
1581 | else { |
1582 | pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n", | |
1583 | K((u64)page_counter_read(&memcg->memsw)), | |
1584 | K((u64)memcg->memsw.max), memcg->memsw.failcnt); | |
1585 | pr_info("kmem: usage %llukB, limit %llukB, failcnt %lu\n", | |
1586 | K((u64)page_counter_read(&memcg->kmem)), | |
1587 | K((u64)memcg->kmem.max), memcg->kmem.failcnt); | |
58cf188e | 1588 | } |
c8713d0b JW |
1589 | |
1590 | pr_info("Memory cgroup stats for "); | |
1591 | pr_cont_cgroup_path(memcg->css.cgroup); | |
1592 | pr_cont(":"); | |
1593 | buf = memory_stat_format(memcg); | |
1594 | if (!buf) | |
1595 | return; | |
1596 | pr_info("%s", buf); | |
1597 | kfree(buf); | |
e222432b BS |
1598 | } |
1599 | ||
a63d83f4 DR |
1600 | /* |
1601 | * Return the memory (and swap, if configured) limit for a memcg. | |
1602 | */ | |
bbec2e15 | 1603 | unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg) |
a63d83f4 | 1604 | { |
8d387a5f WL |
1605 | unsigned long max = READ_ONCE(memcg->memory.max); |
1606 | ||
1607 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) { | |
1608 | if (mem_cgroup_swappiness(memcg)) | |
1609 | max += min(READ_ONCE(memcg->swap.max), | |
1610 | (unsigned long)total_swap_pages); | |
1611 | } else { /* v1 */ | |
1612 | if (mem_cgroup_swappiness(memcg)) { | |
1613 | /* Calculate swap excess capacity from memsw limit */ | |
1614 | unsigned long swap = READ_ONCE(memcg->memsw.max) - max; | |
1615 | ||
1616 | max += min(swap, (unsigned long)total_swap_pages); | |
1617 | } | |
9a5a8f19 | 1618 | } |
bbec2e15 | 1619 | return max; |
a63d83f4 DR |
1620 | } |
1621 | ||
9783aa99 CD |
1622 | unsigned long mem_cgroup_size(struct mem_cgroup *memcg) |
1623 | { | |
1624 | return page_counter_read(&memcg->memory); | |
1625 | } | |
1626 | ||
b6e6edcf | 1627 | static bool mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, |
19965460 | 1628 | int order) |
9cbb78bb | 1629 | { |
6e0fc46d DR |
1630 | struct oom_control oc = { |
1631 | .zonelist = NULL, | |
1632 | .nodemask = NULL, | |
2a966b77 | 1633 | .memcg = memcg, |
6e0fc46d DR |
1634 | .gfp_mask = gfp_mask, |
1635 | .order = order, | |
6e0fc46d | 1636 | }; |
1378b37d | 1637 | bool ret = true; |
9cbb78bb | 1638 | |
7775face TH |
1639 | if (mutex_lock_killable(&oom_lock)) |
1640 | return true; | |
1378b37d YS |
1641 | |
1642 | if (mem_cgroup_margin(memcg) >= (1 << order)) | |
1643 | goto unlock; | |
1644 | ||
7775face TH |
1645 | /* |
1646 | * A few threads which were not waiting at mutex_lock_killable() can | |
1647 | * fail to bail out. Therefore, check again after holding oom_lock. | |
1648 | */ | |
a4ebf1b6 | 1649 | ret = task_is_dying() || out_of_memory(&oc); |
1378b37d YS |
1650 | |
1651 | unlock: | |
dc56401f | 1652 | mutex_unlock(&oom_lock); |
7c5f64f8 | 1653 | return ret; |
9cbb78bb DR |
1654 | } |
1655 | ||
0608f43d | 1656 | static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, |
ef8f2327 | 1657 | pg_data_t *pgdat, |
0608f43d AM |
1658 | gfp_t gfp_mask, |
1659 | unsigned long *total_scanned) | |
1660 | { | |
1661 | struct mem_cgroup *victim = NULL; | |
1662 | int total = 0; | |
1663 | int loop = 0; | |
1664 | unsigned long excess; | |
1665 | unsigned long nr_scanned; | |
1666 | struct mem_cgroup_reclaim_cookie reclaim = { | |
ef8f2327 | 1667 | .pgdat = pgdat, |
0608f43d AM |
1668 | }; |
1669 | ||
3e32cb2e | 1670 | excess = soft_limit_excess(root_memcg); |
0608f43d AM |
1671 | |
1672 | while (1) { | |
1673 | victim = mem_cgroup_iter(root_memcg, victim, &reclaim); | |
1674 | if (!victim) { | |
1675 | loop++; | |
1676 | if (loop >= 2) { | |
1677 | /* | |
1678 | * If we have not been able to reclaim | |
1679 | * anything, it might because there are | |
1680 | * no reclaimable pages under this hierarchy | |
1681 | */ | |
1682 | if (!total) | |
1683 | break; | |
1684 | /* | |
1685 | * We want to do more targeted reclaim. | |
1686 | * excess >> 2 is not to excessive so as to | |
1687 | * reclaim too much, nor too less that we keep | |
1688 | * coming back to reclaim from this cgroup | |
1689 | */ | |
1690 | if (total >= (excess >> 2) || | |
1691 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) | |
1692 | break; | |
1693 | } | |
1694 | continue; | |
1695 | } | |
a9dd0a83 | 1696 | total += mem_cgroup_shrink_node(victim, gfp_mask, false, |
ef8f2327 | 1697 | pgdat, &nr_scanned); |
0608f43d | 1698 | *total_scanned += nr_scanned; |
3e32cb2e | 1699 | if (!soft_limit_excess(root_memcg)) |
0608f43d | 1700 | break; |
6d61ef40 | 1701 | } |
0608f43d AM |
1702 | mem_cgroup_iter_break(root_memcg, victim); |
1703 | return total; | |
6d61ef40 BS |
1704 | } |
1705 | ||
0056f4e6 JW |
1706 | #ifdef CONFIG_LOCKDEP |
1707 | static struct lockdep_map memcg_oom_lock_dep_map = { | |
1708 | .name = "memcg_oom_lock", | |
1709 | }; | |
1710 | #endif | |
1711 | ||
fb2a6fc5 JW |
1712 | static DEFINE_SPINLOCK(memcg_oom_lock); |
1713 | ||
867578cb KH |
1714 | /* |
1715 | * Check OOM-Killer is already running under our hierarchy. | |
1716 | * If someone is running, return false. | |
1717 | */ | |
fb2a6fc5 | 1718 | static bool mem_cgroup_oom_trylock(struct mem_cgroup *memcg) |
867578cb | 1719 | { |
79dfdacc | 1720 | struct mem_cgroup *iter, *failed = NULL; |
a636b327 | 1721 | |
fb2a6fc5 JW |
1722 | spin_lock(&memcg_oom_lock); |
1723 | ||
9f3a0d09 | 1724 | for_each_mem_cgroup_tree(iter, memcg) { |
23751be0 | 1725 | if (iter->oom_lock) { |
79dfdacc MH |
1726 | /* |
1727 | * this subtree of our hierarchy is already locked | |
1728 | * so we cannot give a lock. | |
1729 | */ | |
79dfdacc | 1730 | failed = iter; |
9f3a0d09 JW |
1731 | mem_cgroup_iter_break(memcg, iter); |
1732 | break; | |
23751be0 JW |
1733 | } else |
1734 | iter->oom_lock = true; | |
7d74b06f | 1735 | } |
867578cb | 1736 | |
fb2a6fc5 JW |
1737 | if (failed) { |
1738 | /* | |
1739 | * OK, we failed to lock the whole subtree so we have | |
1740 | * to clean up what we set up to the failing subtree | |
1741 | */ | |
1742 | for_each_mem_cgroup_tree(iter, memcg) { | |
1743 | if (iter == failed) { | |
1744 | mem_cgroup_iter_break(memcg, iter); | |
1745 | break; | |
1746 | } | |
1747 | iter->oom_lock = false; | |
79dfdacc | 1748 | } |
0056f4e6 JW |
1749 | } else |
1750 | mutex_acquire(&memcg_oom_lock_dep_map, 0, 1, _RET_IP_); | |
fb2a6fc5 JW |
1751 | |
1752 | spin_unlock(&memcg_oom_lock); | |
1753 | ||
1754 | return !failed; | |
a636b327 | 1755 | } |
0b7f569e | 1756 | |
fb2a6fc5 | 1757 | static void mem_cgroup_oom_unlock(struct mem_cgroup *memcg) |
0b7f569e | 1758 | { |
7d74b06f KH |
1759 | struct mem_cgroup *iter; |
1760 | ||
fb2a6fc5 | 1761 | spin_lock(&memcg_oom_lock); |
5facae4f | 1762 | mutex_release(&memcg_oom_lock_dep_map, _RET_IP_); |
c0ff4b85 | 1763 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc | 1764 | iter->oom_lock = false; |
fb2a6fc5 | 1765 | spin_unlock(&memcg_oom_lock); |
79dfdacc MH |
1766 | } |
1767 | ||
c0ff4b85 | 1768 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1769 | { |
1770 | struct mem_cgroup *iter; | |
1771 | ||
c2b42d3c | 1772 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1773 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1774 | iter->under_oom++; |
1775 | spin_unlock(&memcg_oom_lock); | |
79dfdacc MH |
1776 | } |
1777 | ||
c0ff4b85 | 1778 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1779 | { |
1780 | struct mem_cgroup *iter; | |
1781 | ||
867578cb | 1782 | /* |
f0953a1b | 1783 | * Be careful about under_oom underflows because a child memcg |
7a52d4d8 | 1784 | * could have been added after mem_cgroup_mark_under_oom. |
867578cb | 1785 | */ |
c2b42d3c | 1786 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1787 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1788 | if (iter->under_oom > 0) |
1789 | iter->under_oom--; | |
1790 | spin_unlock(&memcg_oom_lock); | |
0b7f569e KH |
1791 | } |
1792 | ||
867578cb KH |
1793 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1794 | ||
dc98df5a | 1795 | struct oom_wait_info { |
d79154bb | 1796 | struct mem_cgroup *memcg; |
ac6424b9 | 1797 | wait_queue_entry_t wait; |
dc98df5a KH |
1798 | }; |
1799 | ||
ac6424b9 | 1800 | static int memcg_oom_wake_function(wait_queue_entry_t *wait, |
dc98df5a KH |
1801 | unsigned mode, int sync, void *arg) |
1802 | { | |
d79154bb HD |
1803 | struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg; |
1804 | struct mem_cgroup *oom_wait_memcg; | |
dc98df5a KH |
1805 | struct oom_wait_info *oom_wait_info; |
1806 | ||
1807 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
d79154bb | 1808 | oom_wait_memcg = oom_wait_info->memcg; |
dc98df5a | 1809 | |
2314b42d JW |
1810 | if (!mem_cgroup_is_descendant(wake_memcg, oom_wait_memcg) && |
1811 | !mem_cgroup_is_descendant(oom_wait_memcg, wake_memcg)) | |
dc98df5a | 1812 | return 0; |
dc98df5a KH |
1813 | return autoremove_wake_function(wait, mode, sync, arg); |
1814 | } | |
1815 | ||
c0ff4b85 | 1816 | static void memcg_oom_recover(struct mem_cgroup *memcg) |
3c11ecf4 | 1817 | { |
c2b42d3c TH |
1818 | /* |
1819 | * For the following lockless ->under_oom test, the only required | |
1820 | * guarantee is that it must see the state asserted by an OOM when | |
1821 | * this function is called as a result of userland actions | |
1822 | * triggered by the notification of the OOM. This is trivially | |
1823 | * achieved by invoking mem_cgroup_mark_under_oom() before | |
1824 | * triggering notification. | |
1825 | */ | |
1826 | if (memcg && memcg->under_oom) | |
f4b90b70 | 1827 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg); |
3c11ecf4 KH |
1828 | } |
1829 | ||
becdf89d SB |
1830 | /* |
1831 | * Returns true if successfully killed one or more processes. Though in some | |
1832 | * corner cases it can return true even without killing any process. | |
1833 | */ | |
1834 | static bool mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order) | |
0b7f569e | 1835 | { |
becdf89d | 1836 | bool locked, ret; |
7056d3a3 | 1837 | |
29ef680a | 1838 | if (order > PAGE_ALLOC_COSTLY_ORDER) |
becdf89d | 1839 | return false; |
29ef680a | 1840 | |
7a1adfdd RG |
1841 | memcg_memory_event(memcg, MEMCG_OOM); |
1842 | ||
867578cb | 1843 | /* |
49426420 JW |
1844 | * We are in the middle of the charge context here, so we |
1845 | * don't want to block when potentially sitting on a callstack | |
1846 | * that holds all kinds of filesystem and mm locks. | |
1847 | * | |
29ef680a MH |
1848 | * cgroup1 allows disabling the OOM killer and waiting for outside |
1849 | * handling until the charge can succeed; remember the context and put | |
1850 | * the task to sleep at the end of the page fault when all locks are | |
1851 | * released. | |
49426420 | 1852 | * |
29ef680a MH |
1853 | * On the other hand, in-kernel OOM killer allows for an async victim |
1854 | * memory reclaim (oom_reaper) and that means that we are not solely | |
1855 | * relying on the oom victim to make a forward progress and we can | |
1856 | * invoke the oom killer here. | |
1857 | * | |
1858 | * Please note that mem_cgroup_out_of_memory might fail to find a | |
1859 | * victim and then we have to bail out from the charge path. | |
867578cb | 1860 | */ |
29ef680a | 1861 | if (memcg->oom_kill_disable) { |
becdf89d SB |
1862 | if (current->in_user_fault) { |
1863 | css_get(&memcg->css); | |
1864 | current->memcg_in_oom = memcg; | |
1865 | current->memcg_oom_gfp_mask = mask; | |
1866 | current->memcg_oom_order = order; | |
1867 | } | |
1868 | return false; | |
29ef680a MH |
1869 | } |
1870 | ||
7056d3a3 MH |
1871 | mem_cgroup_mark_under_oom(memcg); |
1872 | ||
1873 | locked = mem_cgroup_oom_trylock(memcg); | |
1874 | ||
1875 | if (locked) | |
1876 | mem_cgroup_oom_notify(memcg); | |
1877 | ||
1878 | mem_cgroup_unmark_under_oom(memcg); | |
becdf89d | 1879 | ret = mem_cgroup_out_of_memory(memcg, mask, order); |
7056d3a3 MH |
1880 | |
1881 | if (locked) | |
1882 | mem_cgroup_oom_unlock(memcg); | |
29ef680a | 1883 | |
7056d3a3 | 1884 | return ret; |
3812c8c8 JW |
1885 | } |
1886 | ||
1887 | /** | |
1888 | * mem_cgroup_oom_synchronize - complete memcg OOM handling | |
49426420 | 1889 | * @handle: actually kill/wait or just clean up the OOM state |
3812c8c8 | 1890 | * |
49426420 JW |
1891 | * This has to be called at the end of a page fault if the memcg OOM |
1892 | * handler was enabled. | |
3812c8c8 | 1893 | * |
49426420 | 1894 | * Memcg supports userspace OOM handling where failed allocations must |
3812c8c8 JW |
1895 | * sleep on a waitqueue until the userspace task resolves the |
1896 | * situation. Sleeping directly in the charge context with all kinds | |
1897 | * of locks held is not a good idea, instead we remember an OOM state | |
1898 | * in the task and mem_cgroup_oom_synchronize() has to be called at | |
49426420 | 1899 | * the end of the page fault to complete the OOM handling. |
3812c8c8 JW |
1900 | * |
1901 | * Returns %true if an ongoing memcg OOM situation was detected and | |
49426420 | 1902 | * completed, %false otherwise. |
3812c8c8 | 1903 | */ |
49426420 | 1904 | bool mem_cgroup_oom_synchronize(bool handle) |
3812c8c8 | 1905 | { |
626ebc41 | 1906 | struct mem_cgroup *memcg = current->memcg_in_oom; |
3812c8c8 | 1907 | struct oom_wait_info owait; |
49426420 | 1908 | bool locked; |
3812c8c8 JW |
1909 | |
1910 | /* OOM is global, do not handle */ | |
3812c8c8 | 1911 | if (!memcg) |
49426420 | 1912 | return false; |
3812c8c8 | 1913 | |
7c5f64f8 | 1914 | if (!handle) |
49426420 | 1915 | goto cleanup; |
3812c8c8 JW |
1916 | |
1917 | owait.memcg = memcg; | |
1918 | owait.wait.flags = 0; | |
1919 | owait.wait.func = memcg_oom_wake_function; | |
1920 | owait.wait.private = current; | |
2055da97 | 1921 | INIT_LIST_HEAD(&owait.wait.entry); |
867578cb | 1922 | |
3812c8c8 | 1923 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
49426420 JW |
1924 | mem_cgroup_mark_under_oom(memcg); |
1925 | ||
1926 | locked = mem_cgroup_oom_trylock(memcg); | |
1927 | ||
1928 | if (locked) | |
1929 | mem_cgroup_oom_notify(memcg); | |
1930 | ||
1931 | if (locked && !memcg->oom_kill_disable) { | |
1932 | mem_cgroup_unmark_under_oom(memcg); | |
1933 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
626ebc41 TH |
1934 | mem_cgroup_out_of_memory(memcg, current->memcg_oom_gfp_mask, |
1935 | current->memcg_oom_order); | |
49426420 | 1936 | } else { |
3812c8c8 | 1937 | schedule(); |
49426420 JW |
1938 | mem_cgroup_unmark_under_oom(memcg); |
1939 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
1940 | } | |
1941 | ||
1942 | if (locked) { | |
fb2a6fc5 JW |
1943 | mem_cgroup_oom_unlock(memcg); |
1944 | /* | |
1945 | * There is no guarantee that an OOM-lock contender | |
1946 | * sees the wakeups triggered by the OOM kill | |
f0953a1b | 1947 | * uncharges. Wake any sleepers explicitly. |
fb2a6fc5 JW |
1948 | */ |
1949 | memcg_oom_recover(memcg); | |
1950 | } | |
49426420 | 1951 | cleanup: |
626ebc41 | 1952 | current->memcg_in_oom = NULL; |
3812c8c8 | 1953 | css_put(&memcg->css); |
867578cb | 1954 | return true; |
0b7f569e KH |
1955 | } |
1956 | ||
3d8b38eb RG |
1957 | /** |
1958 | * mem_cgroup_get_oom_group - get a memory cgroup to clean up after OOM | |
1959 | * @victim: task to be killed by the OOM killer | |
1960 | * @oom_domain: memcg in case of memcg OOM, NULL in case of system-wide OOM | |
1961 | * | |
1962 | * Returns a pointer to a memory cgroup, which has to be cleaned up | |
1963 | * by killing all belonging OOM-killable tasks. | |
1964 | * | |
1965 | * Caller has to call mem_cgroup_put() on the returned non-NULL memcg. | |
1966 | */ | |
1967 | struct mem_cgroup *mem_cgroup_get_oom_group(struct task_struct *victim, | |
1968 | struct mem_cgroup *oom_domain) | |
1969 | { | |
1970 | struct mem_cgroup *oom_group = NULL; | |
1971 | struct mem_cgroup *memcg; | |
1972 | ||
1973 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
1974 | return NULL; | |
1975 | ||
1976 | if (!oom_domain) | |
1977 | oom_domain = root_mem_cgroup; | |
1978 | ||
1979 | rcu_read_lock(); | |
1980 | ||
1981 | memcg = mem_cgroup_from_task(victim); | |
1982 | if (memcg == root_mem_cgroup) | |
1983 | goto out; | |
1984 | ||
48fe267c RG |
1985 | /* |
1986 | * If the victim task has been asynchronously moved to a different | |
1987 | * memory cgroup, we might end up killing tasks outside oom_domain. | |
1988 | * In this case it's better to ignore memory.group.oom. | |
1989 | */ | |
1990 | if (unlikely(!mem_cgroup_is_descendant(memcg, oom_domain))) | |
1991 | goto out; | |
1992 | ||
3d8b38eb RG |
1993 | /* |
1994 | * Traverse the memory cgroup hierarchy from the victim task's | |
1995 | * cgroup up to the OOMing cgroup (or root) to find the | |
1996 | * highest-level memory cgroup with oom.group set. | |
1997 | */ | |
1998 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
1999 | if (memcg->oom_group) | |
2000 | oom_group = memcg; | |
2001 | ||
2002 | if (memcg == oom_domain) | |
2003 | break; | |
2004 | } | |
2005 | ||
2006 | if (oom_group) | |
2007 | css_get(&oom_group->css); | |
2008 | out: | |
2009 | rcu_read_unlock(); | |
2010 | ||
2011 | return oom_group; | |
2012 | } | |
2013 | ||
2014 | void mem_cgroup_print_oom_group(struct mem_cgroup *memcg) | |
2015 | { | |
2016 | pr_info("Tasks in "); | |
2017 | pr_cont_cgroup_path(memcg->css.cgroup); | |
2018 | pr_cont(" are going to be killed due to memory.oom.group set\n"); | |
2019 | } | |
2020 | ||
d7365e78 | 2021 | /** |
f70ad448 MWO |
2022 | * folio_memcg_lock - Bind a folio to its memcg. |
2023 | * @folio: The folio. | |
32047e2a | 2024 | * |
f70ad448 | 2025 | * This function prevents unlocked LRU folios from being moved to |
739f79fc JW |
2026 | * another cgroup. |
2027 | * | |
f70ad448 MWO |
2028 | * It ensures lifetime of the bound memcg. The caller is responsible |
2029 | * for the lifetime of the folio. | |
d69b042f | 2030 | */ |
f70ad448 | 2031 | void folio_memcg_lock(struct folio *folio) |
89c06bd5 KH |
2032 | { |
2033 | struct mem_cgroup *memcg; | |
6de22619 | 2034 | unsigned long flags; |
89c06bd5 | 2035 | |
6de22619 JW |
2036 | /* |
2037 | * The RCU lock is held throughout the transaction. The fast | |
2038 | * path can get away without acquiring the memcg->move_lock | |
2039 | * because page moving starts with an RCU grace period. | |
739f79fc | 2040 | */ |
d7365e78 JW |
2041 | rcu_read_lock(); |
2042 | ||
2043 | if (mem_cgroup_disabled()) | |
1c824a68 | 2044 | return; |
89c06bd5 | 2045 | again: |
f70ad448 | 2046 | memcg = folio_memcg(folio); |
29833315 | 2047 | if (unlikely(!memcg)) |
1c824a68 | 2048 | return; |
d7365e78 | 2049 | |
20ad50d6 AS |
2050 | #ifdef CONFIG_PROVE_LOCKING |
2051 | local_irq_save(flags); | |
2052 | might_lock(&memcg->move_lock); | |
2053 | local_irq_restore(flags); | |
2054 | #endif | |
2055 | ||
bdcbb659 | 2056 | if (atomic_read(&memcg->moving_account) <= 0) |
1c824a68 | 2057 | return; |
89c06bd5 | 2058 | |
6de22619 | 2059 | spin_lock_irqsave(&memcg->move_lock, flags); |
f70ad448 | 2060 | if (memcg != folio_memcg(folio)) { |
6de22619 | 2061 | spin_unlock_irqrestore(&memcg->move_lock, flags); |
89c06bd5 KH |
2062 | goto again; |
2063 | } | |
6de22619 JW |
2064 | |
2065 | /* | |
1c824a68 JW |
2066 | * When charge migration first begins, we can have multiple |
2067 | * critical sections holding the fast-path RCU lock and one | |
2068 | * holding the slowpath move_lock. Track the task who has the | |
2069 | * move_lock for unlock_page_memcg(). | |
6de22619 JW |
2070 | */ |
2071 | memcg->move_lock_task = current; | |
2072 | memcg->move_lock_flags = flags; | |
89c06bd5 | 2073 | } |
f70ad448 MWO |
2074 | |
2075 | void lock_page_memcg(struct page *page) | |
2076 | { | |
2077 | folio_memcg_lock(page_folio(page)); | |
2078 | } | |
89c06bd5 | 2079 | |
f70ad448 | 2080 | static void __folio_memcg_unlock(struct mem_cgroup *memcg) |
89c06bd5 | 2081 | { |
6de22619 JW |
2082 | if (memcg && memcg->move_lock_task == current) { |
2083 | unsigned long flags = memcg->move_lock_flags; | |
2084 | ||
2085 | memcg->move_lock_task = NULL; | |
2086 | memcg->move_lock_flags = 0; | |
2087 | ||
2088 | spin_unlock_irqrestore(&memcg->move_lock, flags); | |
2089 | } | |
89c06bd5 | 2090 | |
d7365e78 | 2091 | rcu_read_unlock(); |
89c06bd5 | 2092 | } |
739f79fc JW |
2093 | |
2094 | /** | |
f70ad448 MWO |
2095 | * folio_memcg_unlock - Release the binding between a folio and its memcg. |
2096 | * @folio: The folio. | |
2097 | * | |
2098 | * This releases the binding created by folio_memcg_lock(). This does | |
2099 | * not change the accounting of this folio to its memcg, but it does | |
2100 | * permit others to change it. | |
739f79fc | 2101 | */ |
f70ad448 | 2102 | void folio_memcg_unlock(struct folio *folio) |
739f79fc | 2103 | { |
f70ad448 MWO |
2104 | __folio_memcg_unlock(folio_memcg(folio)); |
2105 | } | |
9da7b521 | 2106 | |
f70ad448 MWO |
2107 | void unlock_page_memcg(struct page *page) |
2108 | { | |
2109 | folio_memcg_unlock(page_folio(page)); | |
739f79fc | 2110 | } |
89c06bd5 | 2111 | |
fead2b86 | 2112 | struct memcg_stock_pcp { |
56751146 | 2113 | local_lock_t stock_lock; |
fead2b86 MH |
2114 | struct mem_cgroup *cached; /* this never be root cgroup */ |
2115 | unsigned int nr_pages; | |
2116 | ||
bf4f0599 RG |
2117 | #ifdef CONFIG_MEMCG_KMEM |
2118 | struct obj_cgroup *cached_objcg; | |
68ac5b3c | 2119 | struct pglist_data *cached_pgdat; |
bf4f0599 | 2120 | unsigned int nr_bytes; |
68ac5b3c WL |
2121 | int nr_slab_reclaimable_b; |
2122 | int nr_slab_unreclaimable_b; | |
bf4f0599 RG |
2123 | #endif |
2124 | ||
cdec2e42 | 2125 | struct work_struct work; |
26fe6168 | 2126 | unsigned long flags; |
a0db00fc | 2127 | #define FLUSHING_CACHED_CHARGE 0 |
cdec2e42 | 2128 | }; |
56751146 SAS |
2129 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock) = { |
2130 | .stock_lock = INIT_LOCAL_LOCK(stock_lock), | |
2131 | }; | |
9f50fad6 | 2132 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 | 2133 | |
bf4f0599 | 2134 | #ifdef CONFIG_MEMCG_KMEM |
56751146 | 2135 | static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock); |
bf4f0599 RG |
2136 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, |
2137 | struct mem_cgroup *root_memcg); | |
a8c49af3 | 2138 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages); |
bf4f0599 RG |
2139 | |
2140 | #else | |
56751146 | 2141 | static inline struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) |
bf4f0599 | 2142 | { |
56751146 | 2143 | return NULL; |
bf4f0599 RG |
2144 | } |
2145 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, | |
2146 | struct mem_cgroup *root_memcg) | |
2147 | { | |
2148 | return false; | |
2149 | } | |
a8c49af3 YA |
2150 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) |
2151 | { | |
2152 | } | |
bf4f0599 RG |
2153 | #endif |
2154 | ||
a0956d54 SS |
2155 | /** |
2156 | * consume_stock: Try to consume stocked charge on this cpu. | |
2157 | * @memcg: memcg to consume from. | |
2158 | * @nr_pages: how many pages to charge. | |
2159 | * | |
2160 | * The charges will only happen if @memcg matches the current cpu's memcg | |
2161 | * stock, and at least @nr_pages are available in that stock. Failure to | |
2162 | * service an allocation will refill the stock. | |
2163 | * | |
2164 | * returns true if successful, false otherwise. | |
cdec2e42 | 2165 | */ |
a0956d54 | 2166 | static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
2167 | { |
2168 | struct memcg_stock_pcp *stock; | |
db2ba40c | 2169 | unsigned long flags; |
3e32cb2e | 2170 | bool ret = false; |
cdec2e42 | 2171 | |
a983b5eb | 2172 | if (nr_pages > MEMCG_CHARGE_BATCH) |
3e32cb2e | 2173 | return ret; |
a0956d54 | 2174 | |
56751146 | 2175 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
db2ba40c JW |
2176 | |
2177 | stock = this_cpu_ptr(&memcg_stock); | |
3e32cb2e | 2178 | if (memcg == stock->cached && stock->nr_pages >= nr_pages) { |
a0956d54 | 2179 | stock->nr_pages -= nr_pages; |
3e32cb2e JW |
2180 | ret = true; |
2181 | } | |
db2ba40c | 2182 | |
56751146 | 2183 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
db2ba40c | 2184 | |
cdec2e42 KH |
2185 | return ret; |
2186 | } | |
2187 | ||
2188 | /* | |
3e32cb2e | 2189 | * Returns stocks cached in percpu and reset cached information. |
cdec2e42 KH |
2190 | */ |
2191 | static void drain_stock(struct memcg_stock_pcp *stock) | |
2192 | { | |
2193 | struct mem_cgroup *old = stock->cached; | |
2194 | ||
1a3e1f40 JW |
2195 | if (!old) |
2196 | return; | |
2197 | ||
11c9ea4e | 2198 | if (stock->nr_pages) { |
3e32cb2e | 2199 | page_counter_uncharge(&old->memory, stock->nr_pages); |
7941d214 | 2200 | if (do_memsw_account()) |
3e32cb2e | 2201 | page_counter_uncharge(&old->memsw, stock->nr_pages); |
11c9ea4e | 2202 | stock->nr_pages = 0; |
cdec2e42 | 2203 | } |
1a3e1f40 JW |
2204 | |
2205 | css_put(&old->css); | |
cdec2e42 | 2206 | stock->cached = NULL; |
cdec2e42 KH |
2207 | } |
2208 | ||
cdec2e42 KH |
2209 | static void drain_local_stock(struct work_struct *dummy) |
2210 | { | |
db2ba40c | 2211 | struct memcg_stock_pcp *stock; |
56751146 | 2212 | struct obj_cgroup *old = NULL; |
db2ba40c JW |
2213 | unsigned long flags; |
2214 | ||
72f0184c | 2215 | /* |
5c49cf9a MH |
2216 | * The only protection from cpu hotplug (memcg_hotplug_cpu_dead) vs. |
2217 | * drain_stock races is that we always operate on local CPU stock | |
2218 | * here with IRQ disabled | |
72f0184c | 2219 | */ |
56751146 | 2220 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
db2ba40c JW |
2221 | |
2222 | stock = this_cpu_ptr(&memcg_stock); | |
56751146 | 2223 | old = drain_obj_stock(stock); |
cdec2e42 | 2224 | drain_stock(stock); |
26fe6168 | 2225 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
db2ba40c | 2226 | |
56751146 SAS |
2227 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
2228 | if (old) | |
2229 | obj_cgroup_put(old); | |
cdec2e42 KH |
2230 | } |
2231 | ||
2232 | /* | |
3e32cb2e | 2233 | * Cache charges(val) to local per_cpu area. |
320cc51d | 2234 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 2235 | */ |
af9a3b69 | 2236 | static void __refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 | 2237 | { |
db2ba40c | 2238 | struct memcg_stock_pcp *stock; |
cdec2e42 | 2239 | |
db2ba40c | 2240 | stock = this_cpu_ptr(&memcg_stock); |
c0ff4b85 | 2241 | if (stock->cached != memcg) { /* reset if necessary */ |
cdec2e42 | 2242 | drain_stock(stock); |
1a3e1f40 | 2243 | css_get(&memcg->css); |
c0ff4b85 | 2244 | stock->cached = memcg; |
cdec2e42 | 2245 | } |
11c9ea4e | 2246 | stock->nr_pages += nr_pages; |
db2ba40c | 2247 | |
a983b5eb | 2248 | if (stock->nr_pages > MEMCG_CHARGE_BATCH) |
475d0487 | 2249 | drain_stock(stock); |
af9a3b69 JW |
2250 | } |
2251 | ||
2252 | static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) | |
2253 | { | |
2254 | unsigned long flags; | |
475d0487 | 2255 | |
56751146 | 2256 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
af9a3b69 | 2257 | __refill_stock(memcg, nr_pages); |
56751146 | 2258 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
cdec2e42 KH |
2259 | } |
2260 | ||
2261 | /* | |
c0ff4b85 | 2262 | * Drains all per-CPU charge caches for given root_memcg resp. subtree |
6d3d6aa2 | 2263 | * of the hierarchy under it. |
cdec2e42 | 2264 | */ |
6d3d6aa2 | 2265 | static void drain_all_stock(struct mem_cgroup *root_memcg) |
cdec2e42 | 2266 | { |
26fe6168 | 2267 | int cpu, curcpu; |
d38144b7 | 2268 | |
6d3d6aa2 JW |
2269 | /* If someone's already draining, avoid adding running more workers. */ |
2270 | if (!mutex_trylock(&percpu_charge_mutex)) | |
2271 | return; | |
72f0184c MH |
2272 | /* |
2273 | * Notify other cpus that system-wide "drain" is running | |
2274 | * We do not care about races with the cpu hotplug because cpu down | |
2275 | * as well as workers from this path always operate on the local | |
2276 | * per-cpu data. CPU up doesn't touch memcg_stock at all. | |
2277 | */ | |
0790ed62 SAS |
2278 | migrate_disable(); |
2279 | curcpu = smp_processor_id(); | |
cdec2e42 KH |
2280 | for_each_online_cpu(cpu) { |
2281 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
c0ff4b85 | 2282 | struct mem_cgroup *memcg; |
e1a366be | 2283 | bool flush = false; |
26fe6168 | 2284 | |
e1a366be | 2285 | rcu_read_lock(); |
c0ff4b85 | 2286 | memcg = stock->cached; |
e1a366be RG |
2287 | if (memcg && stock->nr_pages && |
2288 | mem_cgroup_is_descendant(memcg, root_memcg)) | |
2289 | flush = true; | |
27fb0956 | 2290 | else if (obj_stock_flush_required(stock, root_memcg)) |
bf4f0599 | 2291 | flush = true; |
e1a366be RG |
2292 | rcu_read_unlock(); |
2293 | ||
2294 | if (flush && | |
2295 | !test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { | |
d1a05b69 MH |
2296 | if (cpu == curcpu) |
2297 | drain_local_stock(&stock->work); | |
2298 | else | |
2299 | schedule_work_on(cpu, &stock->work); | |
2300 | } | |
cdec2e42 | 2301 | } |
0790ed62 | 2302 | migrate_enable(); |
9f50fad6 | 2303 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2304 | } |
2305 | ||
2cd21c89 JW |
2306 | static int memcg_hotplug_cpu_dead(unsigned int cpu) |
2307 | { | |
2308 | struct memcg_stock_pcp *stock; | |
a3d4c05a | 2309 | |
2cd21c89 JW |
2310 | stock = &per_cpu(memcg_stock, cpu); |
2311 | drain_stock(stock); | |
a3d4c05a | 2312 | |
308167fc | 2313 | return 0; |
cdec2e42 KH |
2314 | } |
2315 | ||
b3ff9291 CD |
2316 | static unsigned long reclaim_high(struct mem_cgroup *memcg, |
2317 | unsigned int nr_pages, | |
2318 | gfp_t gfp_mask) | |
f7e1cb6e | 2319 | { |
b3ff9291 CD |
2320 | unsigned long nr_reclaimed = 0; |
2321 | ||
f7e1cb6e | 2322 | do { |
e22c6ed9 JW |
2323 | unsigned long pflags; |
2324 | ||
d1663a90 JK |
2325 | if (page_counter_read(&memcg->memory) <= |
2326 | READ_ONCE(memcg->memory.high)) | |
f7e1cb6e | 2327 | continue; |
e22c6ed9 | 2328 | |
e27be240 | 2329 | memcg_memory_event(memcg, MEMCG_HIGH); |
e22c6ed9 JW |
2330 | |
2331 | psi_memstall_enter(&pflags); | |
b3ff9291 CD |
2332 | nr_reclaimed += try_to_free_mem_cgroup_pages(memcg, nr_pages, |
2333 | gfp_mask, true); | |
e22c6ed9 | 2334 | psi_memstall_leave(&pflags); |
4bf17307 CD |
2335 | } while ((memcg = parent_mem_cgroup(memcg)) && |
2336 | !mem_cgroup_is_root(memcg)); | |
b3ff9291 CD |
2337 | |
2338 | return nr_reclaimed; | |
f7e1cb6e JW |
2339 | } |
2340 | ||
2341 | static void high_work_func(struct work_struct *work) | |
2342 | { | |
2343 | struct mem_cgroup *memcg; | |
2344 | ||
2345 | memcg = container_of(work, struct mem_cgroup, high_work); | |
a983b5eb | 2346 | reclaim_high(memcg, MEMCG_CHARGE_BATCH, GFP_KERNEL); |
f7e1cb6e JW |
2347 | } |
2348 | ||
0e4b01df CD |
2349 | /* |
2350 | * Clamp the maximum sleep time per allocation batch to 2 seconds. This is | |
2351 | * enough to still cause a significant slowdown in most cases, while still | |
2352 | * allowing diagnostics and tracing to proceed without becoming stuck. | |
2353 | */ | |
2354 | #define MEMCG_MAX_HIGH_DELAY_JIFFIES (2UL*HZ) | |
2355 | ||
2356 | /* | |
2357 | * When calculating the delay, we use these either side of the exponentiation to | |
2358 | * maintain precision and scale to a reasonable number of jiffies (see the table | |
2359 | * below. | |
2360 | * | |
2361 | * - MEMCG_DELAY_PRECISION_SHIFT: Extra precision bits while translating the | |
2362 | * overage ratio to a delay. | |
ac5ddd0f | 2363 | * - MEMCG_DELAY_SCALING_SHIFT: The number of bits to scale down the |
0e4b01df CD |
2364 | * proposed penalty in order to reduce to a reasonable number of jiffies, and |
2365 | * to produce a reasonable delay curve. | |
2366 | * | |
2367 | * MEMCG_DELAY_SCALING_SHIFT just happens to be a number that produces a | |
2368 | * reasonable delay curve compared to precision-adjusted overage, not | |
2369 | * penalising heavily at first, but still making sure that growth beyond the | |
2370 | * limit penalises misbehaviour cgroups by slowing them down exponentially. For | |
2371 | * example, with a high of 100 megabytes: | |
2372 | * | |
2373 | * +-------+------------------------+ | |
2374 | * | usage | time to allocate in ms | | |
2375 | * +-------+------------------------+ | |
2376 | * | 100M | 0 | | |
2377 | * | 101M | 6 | | |
2378 | * | 102M | 25 | | |
2379 | * | 103M | 57 | | |
2380 | * | 104M | 102 | | |
2381 | * | 105M | 159 | | |
2382 | * | 106M | 230 | | |
2383 | * | 107M | 313 | | |
2384 | * | 108M | 409 | | |
2385 | * | 109M | 518 | | |
2386 | * | 110M | 639 | | |
2387 | * | 111M | 774 | | |
2388 | * | 112M | 921 | | |
2389 | * | 113M | 1081 | | |
2390 | * | 114M | 1254 | | |
2391 | * | 115M | 1439 | | |
2392 | * | 116M | 1638 | | |
2393 | * | 117M | 1849 | | |
2394 | * | 118M | 2000 | | |
2395 | * | 119M | 2000 | | |
2396 | * | 120M | 2000 | | |
2397 | * +-------+------------------------+ | |
2398 | */ | |
2399 | #define MEMCG_DELAY_PRECISION_SHIFT 20 | |
2400 | #define MEMCG_DELAY_SCALING_SHIFT 14 | |
2401 | ||
8a5dbc65 | 2402 | static u64 calculate_overage(unsigned long usage, unsigned long high) |
b23afb93 | 2403 | { |
8a5dbc65 | 2404 | u64 overage; |
b23afb93 | 2405 | |
8a5dbc65 JK |
2406 | if (usage <= high) |
2407 | return 0; | |
e26733e0 | 2408 | |
8a5dbc65 JK |
2409 | /* |
2410 | * Prevent division by 0 in overage calculation by acting as if | |
2411 | * it was a threshold of 1 page | |
2412 | */ | |
2413 | high = max(high, 1UL); | |
9b8b1754 | 2414 | |
8a5dbc65 JK |
2415 | overage = usage - high; |
2416 | overage <<= MEMCG_DELAY_PRECISION_SHIFT; | |
2417 | return div64_u64(overage, high); | |
2418 | } | |
e26733e0 | 2419 | |
8a5dbc65 JK |
2420 | static u64 mem_find_max_overage(struct mem_cgroup *memcg) |
2421 | { | |
2422 | u64 overage, max_overage = 0; | |
e26733e0 | 2423 | |
8a5dbc65 JK |
2424 | do { |
2425 | overage = calculate_overage(page_counter_read(&memcg->memory), | |
d1663a90 | 2426 | READ_ONCE(memcg->memory.high)); |
8a5dbc65 | 2427 | max_overage = max(overage, max_overage); |
e26733e0 CD |
2428 | } while ((memcg = parent_mem_cgroup(memcg)) && |
2429 | !mem_cgroup_is_root(memcg)); | |
2430 | ||
8a5dbc65 JK |
2431 | return max_overage; |
2432 | } | |
2433 | ||
4b82ab4f JK |
2434 | static u64 swap_find_max_overage(struct mem_cgroup *memcg) |
2435 | { | |
2436 | u64 overage, max_overage = 0; | |
2437 | ||
2438 | do { | |
2439 | overage = calculate_overage(page_counter_read(&memcg->swap), | |
2440 | READ_ONCE(memcg->swap.high)); | |
2441 | if (overage) | |
2442 | memcg_memory_event(memcg, MEMCG_SWAP_HIGH); | |
2443 | max_overage = max(overage, max_overage); | |
2444 | } while ((memcg = parent_mem_cgroup(memcg)) && | |
2445 | !mem_cgroup_is_root(memcg)); | |
2446 | ||
2447 | return max_overage; | |
2448 | } | |
2449 | ||
8a5dbc65 JK |
2450 | /* |
2451 | * Get the number of jiffies that we should penalise a mischievous cgroup which | |
2452 | * is exceeding its memory.high by checking both it and its ancestors. | |
2453 | */ | |
2454 | static unsigned long calculate_high_delay(struct mem_cgroup *memcg, | |
2455 | unsigned int nr_pages, | |
2456 | u64 max_overage) | |
2457 | { | |
2458 | unsigned long penalty_jiffies; | |
2459 | ||
e26733e0 CD |
2460 | if (!max_overage) |
2461 | return 0; | |
0e4b01df CD |
2462 | |
2463 | /* | |
0e4b01df CD |
2464 | * We use overage compared to memory.high to calculate the number of |
2465 | * jiffies to sleep (penalty_jiffies). Ideally this value should be | |
2466 | * fairly lenient on small overages, and increasingly harsh when the | |
2467 | * memcg in question makes it clear that it has no intention of stopping | |
2468 | * its crazy behaviour, so we exponentially increase the delay based on | |
2469 | * overage amount. | |
2470 | */ | |
e26733e0 CD |
2471 | penalty_jiffies = max_overage * max_overage * HZ; |
2472 | penalty_jiffies >>= MEMCG_DELAY_PRECISION_SHIFT; | |
2473 | penalty_jiffies >>= MEMCG_DELAY_SCALING_SHIFT; | |
0e4b01df CD |
2474 | |
2475 | /* | |
2476 | * Factor in the task's own contribution to the overage, such that four | |
2477 | * N-sized allocations are throttled approximately the same as one | |
2478 | * 4N-sized allocation. | |
2479 | * | |
2480 | * MEMCG_CHARGE_BATCH pages is nominal, so work out how much smaller or | |
2481 | * larger the current charge patch is than that. | |
2482 | */ | |
ff144e69 | 2483 | return penalty_jiffies * nr_pages / MEMCG_CHARGE_BATCH; |
e26733e0 CD |
2484 | } |
2485 | ||
2486 | /* | |
2487 | * Scheduled by try_charge() to be executed from the userland return path | |
2488 | * and reclaims memory over the high limit. | |
2489 | */ | |
2490 | void mem_cgroup_handle_over_high(void) | |
2491 | { | |
2492 | unsigned long penalty_jiffies; | |
2493 | unsigned long pflags; | |
b3ff9291 | 2494 | unsigned long nr_reclaimed; |
e26733e0 | 2495 | unsigned int nr_pages = current->memcg_nr_pages_over_high; |
d977aa93 | 2496 | int nr_retries = MAX_RECLAIM_RETRIES; |
e26733e0 | 2497 | struct mem_cgroup *memcg; |
b3ff9291 | 2498 | bool in_retry = false; |
e26733e0 CD |
2499 | |
2500 | if (likely(!nr_pages)) | |
2501 | return; | |
2502 | ||
2503 | memcg = get_mem_cgroup_from_mm(current->mm); | |
e26733e0 CD |
2504 | current->memcg_nr_pages_over_high = 0; |
2505 | ||
b3ff9291 CD |
2506 | retry_reclaim: |
2507 | /* | |
2508 | * The allocating task should reclaim at least the batch size, but for | |
2509 | * subsequent retries we only want to do what's necessary to prevent oom | |
2510 | * or breaching resource isolation. | |
2511 | * | |
2512 | * This is distinct from memory.max or page allocator behaviour because | |
2513 | * memory.high is currently batched, whereas memory.max and the page | |
2514 | * allocator run every time an allocation is made. | |
2515 | */ | |
2516 | nr_reclaimed = reclaim_high(memcg, | |
2517 | in_retry ? SWAP_CLUSTER_MAX : nr_pages, | |
2518 | GFP_KERNEL); | |
2519 | ||
e26733e0 CD |
2520 | /* |
2521 | * memory.high is breached and reclaim is unable to keep up. Throttle | |
2522 | * allocators proactively to slow down excessive growth. | |
2523 | */ | |
8a5dbc65 JK |
2524 | penalty_jiffies = calculate_high_delay(memcg, nr_pages, |
2525 | mem_find_max_overage(memcg)); | |
0e4b01df | 2526 | |
4b82ab4f JK |
2527 | penalty_jiffies += calculate_high_delay(memcg, nr_pages, |
2528 | swap_find_max_overage(memcg)); | |
2529 | ||
ff144e69 JK |
2530 | /* |
2531 | * Clamp the max delay per usermode return so as to still keep the | |
2532 | * application moving forwards and also permit diagnostics, albeit | |
2533 | * extremely slowly. | |
2534 | */ | |
2535 | penalty_jiffies = min(penalty_jiffies, MEMCG_MAX_HIGH_DELAY_JIFFIES); | |
2536 | ||
0e4b01df CD |
2537 | /* |
2538 | * Don't sleep if the amount of jiffies this memcg owes us is so low | |
2539 | * that it's not even worth doing, in an attempt to be nice to those who | |
2540 | * go only a small amount over their memory.high value and maybe haven't | |
2541 | * been aggressively reclaimed enough yet. | |
2542 | */ | |
2543 | if (penalty_jiffies <= HZ / 100) | |
2544 | goto out; | |
2545 | ||
b3ff9291 CD |
2546 | /* |
2547 | * If reclaim is making forward progress but we're still over | |
2548 | * memory.high, we want to encourage that rather than doing allocator | |
2549 | * throttling. | |
2550 | */ | |
2551 | if (nr_reclaimed || nr_retries--) { | |
2552 | in_retry = true; | |
2553 | goto retry_reclaim; | |
2554 | } | |
2555 | ||
0e4b01df CD |
2556 | /* |
2557 | * If we exit early, we're guaranteed to die (since | |
2558 | * schedule_timeout_killable sets TASK_KILLABLE). This means we don't | |
2559 | * need to account for any ill-begotten jiffies to pay them off later. | |
2560 | */ | |
2561 | psi_memstall_enter(&pflags); | |
2562 | schedule_timeout_killable(penalty_jiffies); | |
2563 | psi_memstall_leave(&pflags); | |
2564 | ||
2565 | out: | |
2566 | css_put(&memcg->css); | |
b23afb93 TH |
2567 | } |
2568 | ||
c5c8b16b MS |
2569 | static int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask, |
2570 | unsigned int nr_pages) | |
8a9f3ccd | 2571 | { |
a983b5eb | 2572 | unsigned int batch = max(MEMCG_CHARGE_BATCH, nr_pages); |
d977aa93 | 2573 | int nr_retries = MAX_RECLAIM_RETRIES; |
6539cc05 | 2574 | struct mem_cgroup *mem_over_limit; |
3e32cb2e | 2575 | struct page_counter *counter; |
6539cc05 | 2576 | unsigned long nr_reclaimed; |
a4ebf1b6 | 2577 | bool passed_oom = false; |
b70a2a21 JW |
2578 | bool may_swap = true; |
2579 | bool drained = false; | |
e22c6ed9 | 2580 | unsigned long pflags; |
a636b327 | 2581 | |
6539cc05 | 2582 | retry: |
b6b6cc72 | 2583 | if (consume_stock(memcg, nr_pages)) |
10d53c74 | 2584 | return 0; |
8a9f3ccd | 2585 | |
7941d214 | 2586 | if (!do_memsw_account() || |
6071ca52 JW |
2587 | page_counter_try_charge(&memcg->memsw, batch, &counter)) { |
2588 | if (page_counter_try_charge(&memcg->memory, batch, &counter)) | |
6539cc05 | 2589 | goto done_restock; |
7941d214 | 2590 | if (do_memsw_account()) |
3e32cb2e JW |
2591 | page_counter_uncharge(&memcg->memsw, batch); |
2592 | mem_over_limit = mem_cgroup_from_counter(counter, memory); | |
3fbe7244 | 2593 | } else { |
3e32cb2e | 2594 | mem_over_limit = mem_cgroup_from_counter(counter, memsw); |
b70a2a21 | 2595 | may_swap = false; |
3fbe7244 | 2596 | } |
7a81b88c | 2597 | |
6539cc05 JW |
2598 | if (batch > nr_pages) { |
2599 | batch = nr_pages; | |
2600 | goto retry; | |
2601 | } | |
6d61ef40 | 2602 | |
89a28483 JW |
2603 | /* |
2604 | * Prevent unbounded recursion when reclaim operations need to | |
2605 | * allocate memory. This might exceed the limits temporarily, | |
2606 | * but we prefer facilitating memory reclaim and getting back | |
2607 | * under the limit over triggering OOM kills in these cases. | |
2608 | */ | |
2609 | if (unlikely(current->flags & PF_MEMALLOC)) | |
2610 | goto force; | |
2611 | ||
06b078fc JW |
2612 | if (unlikely(task_in_memcg_oom(current))) |
2613 | goto nomem; | |
2614 | ||
d0164adc | 2615 | if (!gfpflags_allow_blocking(gfp_mask)) |
6539cc05 | 2616 | goto nomem; |
4b534334 | 2617 | |
e27be240 | 2618 | memcg_memory_event(mem_over_limit, MEMCG_MAX); |
241994ed | 2619 | |
e22c6ed9 | 2620 | psi_memstall_enter(&pflags); |
b70a2a21 JW |
2621 | nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages, |
2622 | gfp_mask, may_swap); | |
e22c6ed9 | 2623 | psi_memstall_leave(&pflags); |
6539cc05 | 2624 | |
61e02c74 | 2625 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
6539cc05 | 2626 | goto retry; |
28c34c29 | 2627 | |
b70a2a21 | 2628 | if (!drained) { |
6d3d6aa2 | 2629 | drain_all_stock(mem_over_limit); |
b70a2a21 JW |
2630 | drained = true; |
2631 | goto retry; | |
2632 | } | |
2633 | ||
28c34c29 JW |
2634 | if (gfp_mask & __GFP_NORETRY) |
2635 | goto nomem; | |
6539cc05 JW |
2636 | /* |
2637 | * Even though the limit is exceeded at this point, reclaim | |
2638 | * may have been able to free some pages. Retry the charge | |
2639 | * before killing the task. | |
2640 | * | |
2641 | * Only for regular pages, though: huge pages are rather | |
2642 | * unlikely to succeed so close to the limit, and we fall back | |
2643 | * to regular pages anyway in case of failure. | |
2644 | */ | |
61e02c74 | 2645 | if (nr_reclaimed && nr_pages <= (1 << PAGE_ALLOC_COSTLY_ORDER)) |
6539cc05 JW |
2646 | goto retry; |
2647 | /* | |
2648 | * At task move, charge accounts can be doubly counted. So, it's | |
2649 | * better to wait until the end of task_move if something is going on. | |
2650 | */ | |
2651 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2652 | goto retry; | |
2653 | ||
9b130619 JW |
2654 | if (nr_retries--) |
2655 | goto retry; | |
2656 | ||
38d38493 | 2657 | if (gfp_mask & __GFP_RETRY_MAYFAIL) |
29ef680a MH |
2658 | goto nomem; |
2659 | ||
a4ebf1b6 VA |
2660 | /* Avoid endless loop for tasks bypassed by the oom killer */ |
2661 | if (passed_oom && task_is_dying()) | |
2662 | goto nomem; | |
6539cc05 | 2663 | |
29ef680a MH |
2664 | /* |
2665 | * keep retrying as long as the memcg oom killer is able to make | |
2666 | * a forward progress or bypass the charge if the oom killer | |
2667 | * couldn't make any progress. | |
2668 | */ | |
becdf89d SB |
2669 | if (mem_cgroup_oom(mem_over_limit, gfp_mask, |
2670 | get_order(nr_pages * PAGE_SIZE))) { | |
a4ebf1b6 | 2671 | passed_oom = true; |
d977aa93 | 2672 | nr_retries = MAX_RECLAIM_RETRIES; |
29ef680a | 2673 | goto retry; |
29ef680a | 2674 | } |
7a81b88c | 2675 | nomem: |
1461e8c2 SB |
2676 | /* |
2677 | * Memcg doesn't have a dedicated reserve for atomic | |
2678 | * allocations. But like the global atomic pool, we need to | |
2679 | * put the burden of reclaim on regular allocation requests | |
2680 | * and let these go through as privileged allocations. | |
2681 | */ | |
2682 | if (!(gfp_mask & (__GFP_NOFAIL | __GFP_HIGH))) | |
3168ecbe | 2683 | return -ENOMEM; |
10d53c74 TH |
2684 | force: |
2685 | /* | |
2686 | * The allocation either can't fail or will lead to more memory | |
2687 | * being freed very soon. Allow memory usage go over the limit | |
2688 | * temporarily by force charging it. | |
2689 | */ | |
2690 | page_counter_charge(&memcg->memory, nr_pages); | |
7941d214 | 2691 | if (do_memsw_account()) |
10d53c74 | 2692 | page_counter_charge(&memcg->memsw, nr_pages); |
10d53c74 TH |
2693 | |
2694 | return 0; | |
6539cc05 JW |
2695 | |
2696 | done_restock: | |
2697 | if (batch > nr_pages) | |
2698 | refill_stock(memcg, batch - nr_pages); | |
b23afb93 | 2699 | |
241994ed | 2700 | /* |
b23afb93 TH |
2701 | * If the hierarchy is above the normal consumption range, schedule |
2702 | * reclaim on returning to userland. We can perform reclaim here | |
71baba4b | 2703 | * if __GFP_RECLAIM but let's always punt for simplicity and so that |
b23afb93 TH |
2704 | * GFP_KERNEL can consistently be used during reclaim. @memcg is |
2705 | * not recorded as it most likely matches current's and won't | |
2706 | * change in the meantime. As high limit is checked again before | |
2707 | * reclaim, the cost of mismatch is negligible. | |
241994ed JW |
2708 | */ |
2709 | do { | |
4b82ab4f JK |
2710 | bool mem_high, swap_high; |
2711 | ||
2712 | mem_high = page_counter_read(&memcg->memory) > | |
2713 | READ_ONCE(memcg->memory.high); | |
2714 | swap_high = page_counter_read(&memcg->swap) > | |
2715 | READ_ONCE(memcg->swap.high); | |
2716 | ||
2717 | /* Don't bother a random interrupted task */ | |
086f694a | 2718 | if (!in_task()) { |
4b82ab4f | 2719 | if (mem_high) { |
f7e1cb6e JW |
2720 | schedule_work(&memcg->high_work); |
2721 | break; | |
2722 | } | |
4b82ab4f JK |
2723 | continue; |
2724 | } | |
2725 | ||
2726 | if (mem_high || swap_high) { | |
2727 | /* | |
2728 | * The allocating tasks in this cgroup will need to do | |
2729 | * reclaim or be throttled to prevent further growth | |
2730 | * of the memory or swap footprints. | |
2731 | * | |
2732 | * Target some best-effort fairness between the tasks, | |
2733 | * and distribute reclaim work and delay penalties | |
2734 | * based on how much each task is actually allocating. | |
2735 | */ | |
9516a18a | 2736 | current->memcg_nr_pages_over_high += batch; |
b23afb93 TH |
2737 | set_notify_resume(current); |
2738 | break; | |
2739 | } | |
241994ed | 2740 | } while ((memcg = parent_mem_cgroup(memcg))); |
10d53c74 | 2741 | |
c9afe31e SB |
2742 | if (current->memcg_nr_pages_over_high > MEMCG_CHARGE_BATCH && |
2743 | !(current->flags & PF_MEMALLOC) && | |
2744 | gfpflags_allow_blocking(gfp_mask)) { | |
2745 | mem_cgroup_handle_over_high(); | |
2746 | } | |
10d53c74 | 2747 | return 0; |
7a81b88c | 2748 | } |
8a9f3ccd | 2749 | |
c5c8b16b MS |
2750 | static inline int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, |
2751 | unsigned int nr_pages) | |
2752 | { | |
2753 | if (mem_cgroup_is_root(memcg)) | |
2754 | return 0; | |
2755 | ||
2756 | return try_charge_memcg(memcg, gfp_mask, nr_pages); | |
2757 | } | |
2758 | ||
58056f77 | 2759 | static inline void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) |
a3032a2c | 2760 | { |
ce00a967 JW |
2761 | if (mem_cgroup_is_root(memcg)) |
2762 | return; | |
2763 | ||
3e32cb2e | 2764 | page_counter_uncharge(&memcg->memory, nr_pages); |
7941d214 | 2765 | if (do_memsw_account()) |
3e32cb2e | 2766 | page_counter_uncharge(&memcg->memsw, nr_pages); |
d01dd17f KH |
2767 | } |
2768 | ||
118f2875 | 2769 | static void commit_charge(struct folio *folio, struct mem_cgroup *memcg) |
0a31bc97 | 2770 | { |
118f2875 | 2771 | VM_BUG_ON_FOLIO(folio_memcg(folio), folio); |
0a31bc97 | 2772 | /* |
a5eb011a | 2773 | * Any of the following ensures page's memcg stability: |
0a31bc97 | 2774 | * |
a0b5b414 JW |
2775 | * - the page lock |
2776 | * - LRU isolation | |
2777 | * - lock_page_memcg() | |
2778 | * - exclusive reference | |
0a31bc97 | 2779 | */ |
118f2875 | 2780 | folio->memcg_data = (unsigned long)memcg; |
7a81b88c | 2781 | } |
66e1707b | 2782 | |
84c07d11 | 2783 | #ifdef CONFIG_MEMCG_KMEM |
41eb5df1 WL |
2784 | /* |
2785 | * The allocated objcg pointers array is not accounted directly. | |
2786 | * Moreover, it should not come from DMA buffer and is not readily | |
2787 | * reclaimable. So those GFP bits should be masked off. | |
2788 | */ | |
2789 | #define OBJCGS_CLEAR_MASK (__GFP_DMA | __GFP_RECLAIMABLE | __GFP_ACCOUNT) | |
2790 | ||
a7ebf564 WL |
2791 | /* |
2792 | * mod_objcg_mlstate() may be called with irq enabled, so | |
2793 | * mod_memcg_lruvec_state() should be used. | |
2794 | */ | |
2795 | static inline void mod_objcg_mlstate(struct obj_cgroup *objcg, | |
2796 | struct pglist_data *pgdat, | |
2797 | enum node_stat_item idx, int nr) | |
2798 | { | |
2799 | struct mem_cgroup *memcg; | |
2800 | struct lruvec *lruvec; | |
2801 | ||
2802 | rcu_read_lock(); | |
2803 | memcg = obj_cgroup_memcg(objcg); | |
2804 | lruvec = mem_cgroup_lruvec(memcg, pgdat); | |
2805 | mod_memcg_lruvec_state(lruvec, idx, nr); | |
2806 | rcu_read_unlock(); | |
2807 | } | |
2808 | ||
4b5f8d9a VB |
2809 | int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s, |
2810 | gfp_t gfp, bool new_slab) | |
10befea9 | 2811 | { |
4b5f8d9a | 2812 | unsigned int objects = objs_per_slab(s, slab); |
2e9bd483 | 2813 | unsigned long memcg_data; |
10befea9 RG |
2814 | void *vec; |
2815 | ||
41eb5df1 | 2816 | gfp &= ~OBJCGS_CLEAR_MASK; |
10befea9 | 2817 | vec = kcalloc_node(objects, sizeof(struct obj_cgroup *), gfp, |
4b5f8d9a | 2818 | slab_nid(slab)); |
10befea9 RG |
2819 | if (!vec) |
2820 | return -ENOMEM; | |
2821 | ||
2e9bd483 | 2822 | memcg_data = (unsigned long) vec | MEMCG_DATA_OBJCGS; |
4b5f8d9a | 2823 | if (new_slab) { |
2e9bd483 | 2824 | /* |
4b5f8d9a VB |
2825 | * If the slab is brand new and nobody can yet access its |
2826 | * memcg_data, no synchronization is required and memcg_data can | |
2827 | * be simply assigned. | |
2e9bd483 | 2828 | */ |
4b5f8d9a VB |
2829 | slab->memcg_data = memcg_data; |
2830 | } else if (cmpxchg(&slab->memcg_data, 0, memcg_data)) { | |
2e9bd483 | 2831 | /* |
4b5f8d9a VB |
2832 | * If the slab is already in use, somebody can allocate and |
2833 | * assign obj_cgroups in parallel. In this case the existing | |
2e9bd483 RG |
2834 | * objcg vector should be reused. |
2835 | */ | |
10befea9 | 2836 | kfree(vec); |
2e9bd483 RG |
2837 | return 0; |
2838 | } | |
10befea9 | 2839 | |
2e9bd483 | 2840 | kmemleak_not_leak(vec); |
10befea9 RG |
2841 | return 0; |
2842 | } | |
2843 | ||
fc4db90f RG |
2844 | static __always_inline |
2845 | struct mem_cgroup *mem_cgroup_from_obj_folio(struct folio *folio, void *p) | |
8380ce47 | 2846 | { |
8380ce47 | 2847 | /* |
9855609b RG |
2848 | * Slab objects are accounted individually, not per-page. |
2849 | * Memcg membership data for each individual object is saved in | |
4b5f8d9a | 2850 | * slab->memcg_data. |
8380ce47 | 2851 | */ |
4b5f8d9a VB |
2852 | if (folio_test_slab(folio)) { |
2853 | struct obj_cgroup **objcgs; | |
2854 | struct slab *slab; | |
9855609b RG |
2855 | unsigned int off; |
2856 | ||
4b5f8d9a VB |
2857 | slab = folio_slab(folio); |
2858 | objcgs = slab_objcgs(slab); | |
2859 | if (!objcgs) | |
2860 | return NULL; | |
2861 | ||
2862 | off = obj_to_index(slab->slab_cache, slab, p); | |
2863 | if (objcgs[off]) | |
2864 | return obj_cgroup_memcg(objcgs[off]); | |
10befea9 RG |
2865 | |
2866 | return NULL; | |
9855609b | 2867 | } |
8380ce47 | 2868 | |
bcfe06bf | 2869 | /* |
4b5f8d9a VB |
2870 | * page_memcg_check() is used here, because in theory we can encounter |
2871 | * a folio where the slab flag has been cleared already, but | |
2872 | * slab->memcg_data has not been freed yet | |
bcfe06bf RG |
2873 | * page_memcg_check(page) will guarantee that a proper memory |
2874 | * cgroup pointer or NULL will be returned. | |
2875 | */ | |
4b5f8d9a | 2876 | return page_memcg_check(folio_page(folio, 0)); |
8380ce47 RG |
2877 | } |
2878 | ||
fc4db90f RG |
2879 | /* |
2880 | * Returns a pointer to the memory cgroup to which the kernel object is charged. | |
2881 | * | |
2882 | * A passed kernel object can be a slab object, vmalloc object or a generic | |
2883 | * kernel page, so different mechanisms for getting the memory cgroup pointer | |
2884 | * should be used. | |
2885 | * | |
2886 | * In certain cases (e.g. kernel stacks or large kmallocs with SLUB) the caller | |
2887 | * can not know for sure how the kernel object is implemented. | |
2888 | * mem_cgroup_from_obj() can be safely used in such cases. | |
2889 | * | |
2890 | * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(), | |
2891 | * cgroup_mutex, etc. | |
2892 | */ | |
2893 | struct mem_cgroup *mem_cgroup_from_obj(void *p) | |
2894 | { | |
2895 | struct folio *folio; | |
2896 | ||
2897 | if (mem_cgroup_disabled()) | |
2898 | return NULL; | |
2899 | ||
2900 | if (unlikely(is_vmalloc_addr(p))) | |
2901 | folio = page_folio(vmalloc_to_page(p)); | |
2902 | else | |
2903 | folio = virt_to_folio(p); | |
2904 | ||
2905 | return mem_cgroup_from_obj_folio(folio, p); | |
2906 | } | |
2907 | ||
2908 | /* | |
2909 | * Returns a pointer to the memory cgroup to which the kernel object is charged. | |
2910 | * Similar to mem_cgroup_from_obj(), but faster and not suitable for objects, | |
2911 | * allocated using vmalloc(). | |
2912 | * | |
2913 | * A passed kernel object must be a slab object or a generic kernel page. | |
2914 | * | |
2915 | * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(), | |
2916 | * cgroup_mutex, etc. | |
2917 | */ | |
2918 | struct mem_cgroup *mem_cgroup_from_slab_obj(void *p) | |
2919 | { | |
2920 | if (mem_cgroup_disabled()) | |
2921 | return NULL; | |
2922 | ||
2923 | return mem_cgroup_from_obj_folio(virt_to_folio(p), p); | |
2924 | } | |
2925 | ||
f4840ccf JW |
2926 | static struct obj_cgroup *__get_obj_cgroup_from_memcg(struct mem_cgroup *memcg) |
2927 | { | |
2928 | struct obj_cgroup *objcg = NULL; | |
2929 | ||
2930 | for (; memcg != root_mem_cgroup; memcg = parent_mem_cgroup(memcg)) { | |
2931 | objcg = rcu_dereference(memcg->objcg); | |
2932 | if (objcg && obj_cgroup_tryget(objcg)) | |
2933 | break; | |
2934 | objcg = NULL; | |
2935 | } | |
2936 | return objcg; | |
2937 | } | |
2938 | ||
bf4f0599 RG |
2939 | __always_inline struct obj_cgroup *get_obj_cgroup_from_current(void) |
2940 | { | |
2941 | struct obj_cgroup *objcg = NULL; | |
2942 | struct mem_cgroup *memcg; | |
2943 | ||
279c3393 RG |
2944 | if (memcg_kmem_bypass()) |
2945 | return NULL; | |
2946 | ||
bf4f0599 | 2947 | rcu_read_lock(); |
37d5985c RG |
2948 | if (unlikely(active_memcg())) |
2949 | memcg = active_memcg(); | |
bf4f0599 RG |
2950 | else |
2951 | memcg = mem_cgroup_from_task(current); | |
f4840ccf | 2952 | objcg = __get_obj_cgroup_from_memcg(memcg); |
bf4f0599 | 2953 | rcu_read_unlock(); |
f4840ccf JW |
2954 | return objcg; |
2955 | } | |
2956 | ||
2957 | struct obj_cgroup *get_obj_cgroup_from_page(struct page *page) | |
2958 | { | |
2959 | struct obj_cgroup *objcg; | |
2960 | ||
2961 | if (!memcg_kmem_enabled() || memcg_kmem_bypass()) | |
2962 | return NULL; | |
2963 | ||
2964 | if (PageMemcgKmem(page)) { | |
2965 | objcg = __folio_objcg(page_folio(page)); | |
2966 | obj_cgroup_get(objcg); | |
2967 | } else { | |
2968 | struct mem_cgroup *memcg; | |
bf4f0599 | 2969 | |
f4840ccf JW |
2970 | rcu_read_lock(); |
2971 | memcg = __folio_memcg(page_folio(page)); | |
2972 | if (memcg) | |
2973 | objcg = __get_obj_cgroup_from_memcg(memcg); | |
2974 | else | |
2975 | objcg = NULL; | |
2976 | rcu_read_unlock(); | |
2977 | } | |
bf4f0599 RG |
2978 | return objcg; |
2979 | } | |
2980 | ||
a8c49af3 YA |
2981 | static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) |
2982 | { | |
2983 | mod_memcg_state(memcg, MEMCG_KMEM, nr_pages); | |
2984 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { | |
2985 | if (nr_pages > 0) | |
2986 | page_counter_charge(&memcg->kmem, nr_pages); | |
2987 | else | |
2988 | page_counter_uncharge(&memcg->kmem, -nr_pages); | |
2989 | } | |
2990 | } | |
2991 | ||
2992 | ||
f1286fae MS |
2993 | /* |
2994 | * obj_cgroup_uncharge_pages: uncharge a number of kernel pages from a objcg | |
2995 | * @objcg: object cgroup to uncharge | |
2996 | * @nr_pages: number of pages to uncharge | |
2997 | */ | |
e74d2259 MS |
2998 | static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, |
2999 | unsigned int nr_pages) | |
3000 | { | |
3001 | struct mem_cgroup *memcg; | |
3002 | ||
3003 | memcg = get_mem_cgroup_from_objcg(objcg); | |
e74d2259 | 3004 | |
a8c49af3 | 3005 | memcg_account_kmem(memcg, -nr_pages); |
f1286fae | 3006 | refill_stock(memcg, nr_pages); |
e74d2259 | 3007 | |
e74d2259 | 3008 | css_put(&memcg->css); |
e74d2259 MS |
3009 | } |
3010 | ||
f1286fae MS |
3011 | /* |
3012 | * obj_cgroup_charge_pages: charge a number of kernel pages to a objcg | |
3013 | * @objcg: object cgroup to charge | |
45264778 | 3014 | * @gfp: reclaim mode |
92d0510c | 3015 | * @nr_pages: number of pages to charge |
45264778 VD |
3016 | * |
3017 | * Returns 0 on success, an error code on failure. | |
3018 | */ | |
f1286fae MS |
3019 | static int obj_cgroup_charge_pages(struct obj_cgroup *objcg, gfp_t gfp, |
3020 | unsigned int nr_pages) | |
7ae1e1d0 | 3021 | { |
f1286fae | 3022 | struct mem_cgroup *memcg; |
7ae1e1d0 GC |
3023 | int ret; |
3024 | ||
f1286fae MS |
3025 | memcg = get_mem_cgroup_from_objcg(objcg); |
3026 | ||
c5c8b16b | 3027 | ret = try_charge_memcg(memcg, gfp, nr_pages); |
52c29b04 | 3028 | if (ret) |
f1286fae | 3029 | goto out; |
52c29b04 | 3030 | |
a8c49af3 | 3031 | memcg_account_kmem(memcg, nr_pages); |
f1286fae MS |
3032 | out: |
3033 | css_put(&memcg->css); | |
4b13f64d | 3034 | |
f1286fae | 3035 | return ret; |
4b13f64d RG |
3036 | } |
3037 | ||
45264778 | 3038 | /** |
f4b00eab | 3039 | * __memcg_kmem_charge_page: charge a kmem page to the current memory cgroup |
45264778 VD |
3040 | * @page: page to charge |
3041 | * @gfp: reclaim mode | |
3042 | * @order: allocation order | |
3043 | * | |
3044 | * Returns 0 on success, an error code on failure. | |
3045 | */ | |
f4b00eab | 3046 | int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) |
7ae1e1d0 | 3047 | { |
b4e0b68f | 3048 | struct obj_cgroup *objcg; |
fcff7d7e | 3049 | int ret = 0; |
7ae1e1d0 | 3050 | |
b4e0b68f MS |
3051 | objcg = get_obj_cgroup_from_current(); |
3052 | if (objcg) { | |
3053 | ret = obj_cgroup_charge_pages(objcg, gfp, 1 << order); | |
4d96ba35 | 3054 | if (!ret) { |
b4e0b68f | 3055 | page->memcg_data = (unsigned long)objcg | |
18b2db3b | 3056 | MEMCG_DATA_KMEM; |
1a3e1f40 | 3057 | return 0; |
4d96ba35 | 3058 | } |
b4e0b68f | 3059 | obj_cgroup_put(objcg); |
c4159a75 | 3060 | } |
d05e83a6 | 3061 | return ret; |
7ae1e1d0 | 3062 | } |
49a18eae | 3063 | |
45264778 | 3064 | /** |
f4b00eab | 3065 | * __memcg_kmem_uncharge_page: uncharge a kmem page |
45264778 VD |
3066 | * @page: page to uncharge |
3067 | * @order: allocation order | |
3068 | */ | |
f4b00eab | 3069 | void __memcg_kmem_uncharge_page(struct page *page, int order) |
7ae1e1d0 | 3070 | { |
1b7e4464 | 3071 | struct folio *folio = page_folio(page); |
b4e0b68f | 3072 | struct obj_cgroup *objcg; |
f3ccb2c4 | 3073 | unsigned int nr_pages = 1 << order; |
7ae1e1d0 | 3074 | |
1b7e4464 | 3075 | if (!folio_memcg_kmem(folio)) |
7ae1e1d0 GC |
3076 | return; |
3077 | ||
1b7e4464 | 3078 | objcg = __folio_objcg(folio); |
b4e0b68f | 3079 | obj_cgroup_uncharge_pages(objcg, nr_pages); |
1b7e4464 | 3080 | folio->memcg_data = 0; |
b4e0b68f | 3081 | obj_cgroup_put(objcg); |
60d3fd32 | 3082 | } |
bf4f0599 | 3083 | |
68ac5b3c WL |
3084 | void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, |
3085 | enum node_stat_item idx, int nr) | |
3086 | { | |
fead2b86 | 3087 | struct memcg_stock_pcp *stock; |
56751146 | 3088 | struct obj_cgroup *old = NULL; |
68ac5b3c WL |
3089 | unsigned long flags; |
3090 | int *bytes; | |
3091 | ||
56751146 | 3092 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3093 | stock = this_cpu_ptr(&memcg_stock); |
3094 | ||
68ac5b3c WL |
3095 | /* |
3096 | * Save vmstat data in stock and skip vmstat array update unless | |
3097 | * accumulating over a page of vmstat data or when pgdat or idx | |
3098 | * changes. | |
3099 | */ | |
3100 | if (stock->cached_objcg != objcg) { | |
56751146 | 3101 | old = drain_obj_stock(stock); |
68ac5b3c WL |
3102 | obj_cgroup_get(objcg); |
3103 | stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) | |
3104 | ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; | |
3105 | stock->cached_objcg = objcg; | |
3106 | stock->cached_pgdat = pgdat; | |
3107 | } else if (stock->cached_pgdat != pgdat) { | |
3108 | /* Flush the existing cached vmstat data */ | |
7fa0dacb WL |
3109 | struct pglist_data *oldpg = stock->cached_pgdat; |
3110 | ||
68ac5b3c | 3111 | if (stock->nr_slab_reclaimable_b) { |
7fa0dacb | 3112 | mod_objcg_mlstate(objcg, oldpg, NR_SLAB_RECLAIMABLE_B, |
68ac5b3c WL |
3113 | stock->nr_slab_reclaimable_b); |
3114 | stock->nr_slab_reclaimable_b = 0; | |
3115 | } | |
3116 | if (stock->nr_slab_unreclaimable_b) { | |
7fa0dacb | 3117 | mod_objcg_mlstate(objcg, oldpg, NR_SLAB_UNRECLAIMABLE_B, |
68ac5b3c WL |
3118 | stock->nr_slab_unreclaimable_b); |
3119 | stock->nr_slab_unreclaimable_b = 0; | |
3120 | } | |
3121 | stock->cached_pgdat = pgdat; | |
3122 | } | |
3123 | ||
3124 | bytes = (idx == NR_SLAB_RECLAIMABLE_B) ? &stock->nr_slab_reclaimable_b | |
3125 | : &stock->nr_slab_unreclaimable_b; | |
3126 | /* | |
3127 | * Even for large object >= PAGE_SIZE, the vmstat data will still be | |
3128 | * cached locally at least once before pushing it out. | |
3129 | */ | |
3130 | if (!*bytes) { | |
3131 | *bytes = nr; | |
3132 | nr = 0; | |
3133 | } else { | |
3134 | *bytes += nr; | |
3135 | if (abs(*bytes) > PAGE_SIZE) { | |
3136 | nr = *bytes; | |
3137 | *bytes = 0; | |
3138 | } else { | |
3139 | nr = 0; | |
3140 | } | |
3141 | } | |
3142 | if (nr) | |
3143 | mod_objcg_mlstate(objcg, pgdat, idx, nr); | |
3144 | ||
56751146 SAS |
3145 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
3146 | if (old) | |
3147 | obj_cgroup_put(old); | |
68ac5b3c WL |
3148 | } |
3149 | ||
bf4f0599 RG |
3150 | static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes) |
3151 | { | |
fead2b86 | 3152 | struct memcg_stock_pcp *stock; |
bf4f0599 RG |
3153 | unsigned long flags; |
3154 | bool ret = false; | |
3155 | ||
56751146 | 3156 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3157 | |
3158 | stock = this_cpu_ptr(&memcg_stock); | |
bf4f0599 RG |
3159 | if (objcg == stock->cached_objcg && stock->nr_bytes >= nr_bytes) { |
3160 | stock->nr_bytes -= nr_bytes; | |
3161 | ret = true; | |
3162 | } | |
3163 | ||
56751146 | 3164 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
bf4f0599 RG |
3165 | |
3166 | return ret; | |
3167 | } | |
3168 | ||
56751146 | 3169 | static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) |
bf4f0599 RG |
3170 | { |
3171 | struct obj_cgroup *old = stock->cached_objcg; | |
3172 | ||
3173 | if (!old) | |
56751146 | 3174 | return NULL; |
bf4f0599 RG |
3175 | |
3176 | if (stock->nr_bytes) { | |
3177 | unsigned int nr_pages = stock->nr_bytes >> PAGE_SHIFT; | |
3178 | unsigned int nr_bytes = stock->nr_bytes & (PAGE_SIZE - 1); | |
3179 | ||
af9a3b69 JW |
3180 | if (nr_pages) { |
3181 | struct mem_cgroup *memcg; | |
3182 | ||
3183 | memcg = get_mem_cgroup_from_objcg(old); | |
3184 | ||
3185 | memcg_account_kmem(memcg, -nr_pages); | |
3186 | __refill_stock(memcg, nr_pages); | |
3187 | ||
3188 | css_put(&memcg->css); | |
3189 | } | |
bf4f0599 RG |
3190 | |
3191 | /* | |
3192 | * The leftover is flushed to the centralized per-memcg value. | |
3193 | * On the next attempt to refill obj stock it will be moved | |
3194 | * to a per-cpu stock (probably, on an other CPU), see | |
3195 | * refill_obj_stock(). | |
3196 | * | |
3197 | * How often it's flushed is a trade-off between the memory | |
3198 | * limit enforcement accuracy and potential CPU contention, | |
3199 | * so it might be changed in the future. | |
3200 | */ | |
3201 | atomic_add(nr_bytes, &old->nr_charged_bytes); | |
3202 | stock->nr_bytes = 0; | |
3203 | } | |
3204 | ||
68ac5b3c WL |
3205 | /* |
3206 | * Flush the vmstat data in current stock | |
3207 | */ | |
3208 | if (stock->nr_slab_reclaimable_b || stock->nr_slab_unreclaimable_b) { | |
3209 | if (stock->nr_slab_reclaimable_b) { | |
3210 | mod_objcg_mlstate(old, stock->cached_pgdat, | |
3211 | NR_SLAB_RECLAIMABLE_B, | |
3212 | stock->nr_slab_reclaimable_b); | |
3213 | stock->nr_slab_reclaimable_b = 0; | |
3214 | } | |
3215 | if (stock->nr_slab_unreclaimable_b) { | |
3216 | mod_objcg_mlstate(old, stock->cached_pgdat, | |
3217 | NR_SLAB_UNRECLAIMABLE_B, | |
3218 | stock->nr_slab_unreclaimable_b); | |
3219 | stock->nr_slab_unreclaimable_b = 0; | |
3220 | } | |
3221 | stock->cached_pgdat = NULL; | |
3222 | } | |
3223 | ||
bf4f0599 | 3224 | stock->cached_objcg = NULL; |
56751146 SAS |
3225 | /* |
3226 | * The `old' objects needs to be released by the caller via | |
3227 | * obj_cgroup_put() outside of memcg_stock_pcp::stock_lock. | |
3228 | */ | |
3229 | return old; | |
bf4f0599 RG |
3230 | } |
3231 | ||
3232 | static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, | |
3233 | struct mem_cgroup *root_memcg) | |
3234 | { | |
3235 | struct mem_cgroup *memcg; | |
3236 | ||
fead2b86 MH |
3237 | if (stock->cached_objcg) { |
3238 | memcg = obj_cgroup_memcg(stock->cached_objcg); | |
bf4f0599 RG |
3239 | if (memcg && mem_cgroup_is_descendant(memcg, root_memcg)) |
3240 | return true; | |
3241 | } | |
3242 | ||
3243 | return false; | |
3244 | } | |
3245 | ||
5387c904 WL |
3246 | static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes, |
3247 | bool allow_uncharge) | |
bf4f0599 | 3248 | { |
fead2b86 | 3249 | struct memcg_stock_pcp *stock; |
56751146 | 3250 | struct obj_cgroup *old = NULL; |
bf4f0599 | 3251 | unsigned long flags; |
5387c904 | 3252 | unsigned int nr_pages = 0; |
bf4f0599 | 3253 | |
56751146 | 3254 | local_lock_irqsave(&memcg_stock.stock_lock, flags); |
fead2b86 MH |
3255 | |
3256 | stock = this_cpu_ptr(&memcg_stock); | |
bf4f0599 | 3257 | if (stock->cached_objcg != objcg) { /* reset if necessary */ |
56751146 | 3258 | old = drain_obj_stock(stock); |
bf4f0599 RG |
3259 | obj_cgroup_get(objcg); |
3260 | stock->cached_objcg = objcg; | |
5387c904 WL |
3261 | stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) |
3262 | ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; | |
3263 | allow_uncharge = true; /* Allow uncharge when objcg changes */ | |
bf4f0599 RG |
3264 | } |
3265 | stock->nr_bytes += nr_bytes; | |
3266 | ||
5387c904 WL |
3267 | if (allow_uncharge && (stock->nr_bytes > PAGE_SIZE)) { |
3268 | nr_pages = stock->nr_bytes >> PAGE_SHIFT; | |
3269 | stock->nr_bytes &= (PAGE_SIZE - 1); | |
3270 | } | |
bf4f0599 | 3271 | |
56751146 SAS |
3272 | local_unlock_irqrestore(&memcg_stock.stock_lock, flags); |
3273 | if (old) | |
3274 | obj_cgroup_put(old); | |
5387c904 WL |
3275 | |
3276 | if (nr_pages) | |
3277 | obj_cgroup_uncharge_pages(objcg, nr_pages); | |
bf4f0599 RG |
3278 | } |
3279 | ||
3280 | int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size) | |
3281 | { | |
bf4f0599 RG |
3282 | unsigned int nr_pages, nr_bytes; |
3283 | int ret; | |
3284 | ||
3285 | if (consume_obj_stock(objcg, size)) | |
3286 | return 0; | |
3287 | ||
3288 | /* | |
5387c904 | 3289 | * In theory, objcg->nr_charged_bytes can have enough |
bf4f0599 | 3290 | * pre-charged bytes to satisfy the allocation. However, |
5387c904 WL |
3291 | * flushing objcg->nr_charged_bytes requires two atomic |
3292 | * operations, and objcg->nr_charged_bytes can't be big. | |
3293 | * The shared objcg->nr_charged_bytes can also become a | |
3294 | * performance bottleneck if all tasks of the same memcg are | |
3295 | * trying to update it. So it's better to ignore it and try | |
3296 | * grab some new pages. The stock's nr_bytes will be flushed to | |
3297 | * objcg->nr_charged_bytes later on when objcg changes. | |
3298 | * | |
3299 | * The stock's nr_bytes may contain enough pre-charged bytes | |
3300 | * to allow one less page from being charged, but we can't rely | |
3301 | * on the pre-charged bytes not being changed outside of | |
3302 | * consume_obj_stock() or refill_obj_stock(). So ignore those | |
3303 | * pre-charged bytes as well when charging pages. To avoid a | |
3304 | * page uncharge right after a page charge, we set the | |
3305 | * allow_uncharge flag to false when calling refill_obj_stock() | |
3306 | * to temporarily allow the pre-charged bytes to exceed the page | |
3307 | * size limit. The maximum reachable value of the pre-charged | |
3308 | * bytes is (sizeof(object) + PAGE_SIZE - 2) if there is no data | |
3309 | * race. | |
bf4f0599 | 3310 | */ |
bf4f0599 RG |
3311 | nr_pages = size >> PAGE_SHIFT; |
3312 | nr_bytes = size & (PAGE_SIZE - 1); | |
3313 | ||
3314 | if (nr_bytes) | |
3315 | nr_pages += 1; | |
3316 | ||
e74d2259 | 3317 | ret = obj_cgroup_charge_pages(objcg, gfp, nr_pages); |
bf4f0599 | 3318 | if (!ret && nr_bytes) |
5387c904 | 3319 | refill_obj_stock(objcg, PAGE_SIZE - nr_bytes, false); |
bf4f0599 | 3320 | |
bf4f0599 RG |
3321 | return ret; |
3322 | } | |
3323 | ||
3324 | void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size) | |
3325 | { | |
5387c904 | 3326 | refill_obj_stock(objcg, size, true); |
bf4f0599 RG |
3327 | } |
3328 | ||
84c07d11 | 3329 | #endif /* CONFIG_MEMCG_KMEM */ |
7ae1e1d0 | 3330 | |
ca3e0214 | 3331 | /* |
be6c8982 | 3332 | * Because page_memcg(head) is not set on tails, set it now. |
ca3e0214 | 3333 | */ |
be6c8982 | 3334 | void split_page_memcg(struct page *head, unsigned int nr) |
ca3e0214 | 3335 | { |
1b7e4464 MWO |
3336 | struct folio *folio = page_folio(head); |
3337 | struct mem_cgroup *memcg = folio_memcg(folio); | |
e94c8a9c | 3338 | int i; |
ca3e0214 | 3339 | |
be6c8982 | 3340 | if (mem_cgroup_disabled() || !memcg) |
3d37c4a9 | 3341 | return; |
b070e65c | 3342 | |
be6c8982 | 3343 | for (i = 1; i < nr; i++) |
1b7e4464 | 3344 | folio_page(folio, i)->memcg_data = folio->memcg_data; |
b4e0b68f | 3345 | |
1b7e4464 MWO |
3346 | if (folio_memcg_kmem(folio)) |
3347 | obj_cgroup_get_many(__folio_objcg(folio), nr - 1); | |
b4e0b68f MS |
3348 | else |
3349 | css_get_many(&memcg->css, nr - 1); | |
ca3e0214 | 3350 | } |
ca3e0214 | 3351 | |
c255a458 | 3352 | #ifdef CONFIG_MEMCG_SWAP |
02491447 DN |
3353 | /** |
3354 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
3355 | * @entry: swap entry to be moved | |
3356 | * @from: mem_cgroup which the entry is moved from | |
3357 | * @to: mem_cgroup which the entry is moved to | |
3358 | * | |
3359 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
3360 | * as the mem_cgroup's id of @from. | |
3361 | * | |
3362 | * Returns 0 on success, -EINVAL on failure. | |
3363 | * | |
3e32cb2e | 3364 | * The caller must have charged to @to, IOW, called page_counter_charge() about |
02491447 DN |
3365 | * both res and memsw, and called css_get(). |
3366 | */ | |
3367 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 3368 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
3369 | { |
3370 | unsigned short old_id, new_id; | |
3371 | ||
34c00c31 LZ |
3372 | old_id = mem_cgroup_id(from); |
3373 | new_id = mem_cgroup_id(to); | |
02491447 DN |
3374 | |
3375 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
c9019e9b JW |
3376 | mod_memcg_state(from, MEMCG_SWAP, -1); |
3377 | mod_memcg_state(to, MEMCG_SWAP, 1); | |
02491447 DN |
3378 | return 0; |
3379 | } | |
3380 | return -EINVAL; | |
3381 | } | |
3382 | #else | |
3383 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 3384 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
3385 | { |
3386 | return -EINVAL; | |
3387 | } | |
8c7c6e34 | 3388 | #endif |
d13d1443 | 3389 | |
bbec2e15 | 3390 | static DEFINE_MUTEX(memcg_max_mutex); |
f212ad7c | 3391 | |
bbec2e15 RG |
3392 | static int mem_cgroup_resize_max(struct mem_cgroup *memcg, |
3393 | unsigned long max, bool memsw) | |
628f4235 | 3394 | { |
3e32cb2e | 3395 | bool enlarge = false; |
bb4a7ea2 | 3396 | bool drained = false; |
3e32cb2e | 3397 | int ret; |
c054a78c YZ |
3398 | bool limits_invariant; |
3399 | struct page_counter *counter = memsw ? &memcg->memsw : &memcg->memory; | |
81d39c20 | 3400 | |
3e32cb2e | 3401 | do { |
628f4235 KH |
3402 | if (signal_pending(current)) { |
3403 | ret = -EINTR; | |
3404 | break; | |
3405 | } | |
3e32cb2e | 3406 | |
bbec2e15 | 3407 | mutex_lock(&memcg_max_mutex); |
c054a78c YZ |
3408 | /* |
3409 | * Make sure that the new limit (memsw or memory limit) doesn't | |
bbec2e15 | 3410 | * break our basic invariant rule memory.max <= memsw.max. |
c054a78c | 3411 | */ |
15b42562 | 3412 | limits_invariant = memsw ? max >= READ_ONCE(memcg->memory.max) : |
bbec2e15 | 3413 | max <= memcg->memsw.max; |
c054a78c | 3414 | if (!limits_invariant) { |
bbec2e15 | 3415 | mutex_unlock(&memcg_max_mutex); |
8c7c6e34 | 3416 | ret = -EINVAL; |
8c7c6e34 KH |
3417 | break; |
3418 | } | |
bbec2e15 | 3419 | if (max > counter->max) |
3e32cb2e | 3420 | enlarge = true; |
bbec2e15 RG |
3421 | ret = page_counter_set_max(counter, max); |
3422 | mutex_unlock(&memcg_max_mutex); | |
8c7c6e34 KH |
3423 | |
3424 | if (!ret) | |
3425 | break; | |
3426 | ||
bb4a7ea2 SB |
3427 | if (!drained) { |
3428 | drain_all_stock(memcg); | |
3429 | drained = true; | |
3430 | continue; | |
3431 | } | |
3432 | ||
1ab5c056 AR |
3433 | if (!try_to_free_mem_cgroup_pages(memcg, 1, |
3434 | GFP_KERNEL, !memsw)) { | |
3435 | ret = -EBUSY; | |
3436 | break; | |
3437 | } | |
3438 | } while (true); | |
3e32cb2e | 3439 | |
3c11ecf4 KH |
3440 | if (!ret && enlarge) |
3441 | memcg_oom_recover(memcg); | |
3e32cb2e | 3442 | |
628f4235 KH |
3443 | return ret; |
3444 | } | |
3445 | ||
ef8f2327 | 3446 | unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, |
0608f43d AM |
3447 | gfp_t gfp_mask, |
3448 | unsigned long *total_scanned) | |
3449 | { | |
3450 | unsigned long nr_reclaimed = 0; | |
ef8f2327 | 3451 | struct mem_cgroup_per_node *mz, *next_mz = NULL; |
0608f43d AM |
3452 | unsigned long reclaimed; |
3453 | int loop = 0; | |
ef8f2327 | 3454 | struct mem_cgroup_tree_per_node *mctz; |
3e32cb2e | 3455 | unsigned long excess; |
0608f43d AM |
3456 | |
3457 | if (order > 0) | |
3458 | return 0; | |
3459 | ||
2ab082ba | 3460 | mctz = soft_limit_tree.rb_tree_per_node[pgdat->node_id]; |
d6507ff5 MH |
3461 | |
3462 | /* | |
3463 | * Do not even bother to check the largest node if the root | |
3464 | * is empty. Do it lockless to prevent lock bouncing. Races | |
3465 | * are acceptable as soft limit is best effort anyway. | |
3466 | */ | |
bfc7228b | 3467 | if (!mctz || RB_EMPTY_ROOT(&mctz->rb_root)) |
d6507ff5 MH |
3468 | return 0; |
3469 | ||
0608f43d AM |
3470 | /* |
3471 | * This loop can run a while, specially if mem_cgroup's continuously | |
3472 | * keep exceeding their soft limit and putting the system under | |
3473 | * pressure | |
3474 | */ | |
3475 | do { | |
3476 | if (next_mz) | |
3477 | mz = next_mz; | |
3478 | else | |
3479 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
3480 | if (!mz) | |
3481 | break; | |
3482 | ||
ef8f2327 | 3483 | reclaimed = mem_cgroup_soft_reclaim(mz->memcg, pgdat, |
d8f65338 | 3484 | gfp_mask, total_scanned); |
0608f43d | 3485 | nr_reclaimed += reclaimed; |
0a31bc97 | 3486 | spin_lock_irq(&mctz->lock); |
0608f43d AM |
3487 | |
3488 | /* | |
3489 | * If we failed to reclaim anything from this memory cgroup | |
3490 | * it is time to move on to the next cgroup | |
3491 | */ | |
3492 | next_mz = NULL; | |
bc2f2e7f VD |
3493 | if (!reclaimed) |
3494 | next_mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
3495 | ||
3e32cb2e | 3496 | excess = soft_limit_excess(mz->memcg); |
0608f43d AM |
3497 | /* |
3498 | * One school of thought says that we should not add | |
3499 | * back the node to the tree if reclaim returns 0. | |
3500 | * But our reclaim could return 0, simply because due | |
3501 | * to priority we are exposing a smaller subset of | |
3502 | * memory to reclaim from. Consider this as a longer | |
3503 | * term TODO. | |
3504 | */ | |
3505 | /* If excess == 0, no tree ops */ | |
cf2c8127 | 3506 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 3507 | spin_unlock_irq(&mctz->lock); |
0608f43d AM |
3508 | css_put(&mz->memcg->css); |
3509 | loop++; | |
3510 | /* | |
3511 | * Could not reclaim anything and there are no more | |
3512 | * mem cgroups to try or we seem to be looping without | |
3513 | * reclaiming anything. | |
3514 | */ | |
3515 | if (!nr_reclaimed && | |
3516 | (next_mz == NULL || | |
3517 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
3518 | break; | |
3519 | } while (!nr_reclaimed); | |
3520 | if (next_mz) | |
3521 | css_put(&next_mz->memcg->css); | |
3522 | return nr_reclaimed; | |
3523 | } | |
3524 | ||
c26251f9 | 3525 | /* |
51038171 | 3526 | * Reclaims as many pages from the given memcg as possible. |
c26251f9 MH |
3527 | * |
3528 | * Caller is responsible for holding css reference for memcg. | |
3529 | */ | |
3530 | static int mem_cgroup_force_empty(struct mem_cgroup *memcg) | |
3531 | { | |
d977aa93 | 3532 | int nr_retries = MAX_RECLAIM_RETRIES; |
c26251f9 | 3533 | |
c1e862c1 KH |
3534 | /* we call try-to-free pages for make this cgroup empty */ |
3535 | lru_add_drain_all(); | |
d12c60f6 JS |
3536 | |
3537 | drain_all_stock(memcg); | |
3538 | ||
f817ed48 | 3539 | /* try to free all pages in this cgroup */ |
3e32cb2e | 3540 | while (nr_retries && page_counter_read(&memcg->memory)) { |
c26251f9 MH |
3541 | if (signal_pending(current)) |
3542 | return -EINTR; | |
3543 | ||
69392a40 | 3544 | if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, true)) |
f817ed48 | 3545 | nr_retries--; |
f817ed48 | 3546 | } |
ab5196c2 MH |
3547 | |
3548 | return 0; | |
cc847582 KH |
3549 | } |
3550 | ||
6770c64e TH |
3551 | static ssize_t mem_cgroup_force_empty_write(struct kernfs_open_file *of, |
3552 | char *buf, size_t nbytes, | |
3553 | loff_t off) | |
c1e862c1 | 3554 | { |
6770c64e | 3555 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
c26251f9 | 3556 | |
d8423011 MH |
3557 | if (mem_cgroup_is_root(memcg)) |
3558 | return -EINVAL; | |
6770c64e | 3559 | return mem_cgroup_force_empty(memcg) ?: nbytes; |
c1e862c1 KH |
3560 | } |
3561 | ||
182446d0 TH |
3562 | static u64 mem_cgroup_hierarchy_read(struct cgroup_subsys_state *css, |
3563 | struct cftype *cft) | |
18f59ea7 | 3564 | { |
bef8620c | 3565 | return 1; |
18f59ea7 BS |
3566 | } |
3567 | ||
182446d0 TH |
3568 | static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css, |
3569 | struct cftype *cft, u64 val) | |
18f59ea7 | 3570 | { |
bef8620c | 3571 | if (val == 1) |
0b8f73e1 | 3572 | return 0; |
567fb435 | 3573 | |
bef8620c RG |
3574 | pr_warn_once("Non-hierarchical mode is deprecated. " |
3575 | "Please report your usecase to linux-mm@kvack.org if you " | |
3576 | "depend on this functionality.\n"); | |
567fb435 | 3577 | |
bef8620c | 3578 | return -EINVAL; |
18f59ea7 BS |
3579 | } |
3580 | ||
6f646156 | 3581 | static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) |
ce00a967 | 3582 | { |
42a30035 | 3583 | unsigned long val; |
ce00a967 | 3584 | |
3e32cb2e | 3585 | if (mem_cgroup_is_root(memcg)) { |
fd25a9e0 | 3586 | mem_cgroup_flush_stats(); |
0d1c2072 | 3587 | val = memcg_page_state(memcg, NR_FILE_PAGES) + |
be5d0a74 | 3588 | memcg_page_state(memcg, NR_ANON_MAPPED); |
42a30035 JW |
3589 | if (swap) |
3590 | val += memcg_page_state(memcg, MEMCG_SWAP); | |
3e32cb2e | 3591 | } else { |
ce00a967 | 3592 | if (!swap) |
3e32cb2e | 3593 | val = page_counter_read(&memcg->memory); |
ce00a967 | 3594 | else |
3e32cb2e | 3595 | val = page_counter_read(&memcg->memsw); |
ce00a967 | 3596 | } |
c12176d3 | 3597 | return val; |
ce00a967 JW |
3598 | } |
3599 | ||
3e32cb2e JW |
3600 | enum { |
3601 | RES_USAGE, | |
3602 | RES_LIMIT, | |
3603 | RES_MAX_USAGE, | |
3604 | RES_FAILCNT, | |
3605 | RES_SOFT_LIMIT, | |
3606 | }; | |
ce00a967 | 3607 | |
791badbd | 3608 | static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css, |
05b84301 | 3609 | struct cftype *cft) |
8cdea7c0 | 3610 | { |
182446d0 | 3611 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3e32cb2e | 3612 | struct page_counter *counter; |
af36f906 | 3613 | |
3e32cb2e | 3614 | switch (MEMFILE_TYPE(cft->private)) { |
8c7c6e34 | 3615 | case _MEM: |
3e32cb2e JW |
3616 | counter = &memcg->memory; |
3617 | break; | |
8c7c6e34 | 3618 | case _MEMSWAP: |
3e32cb2e JW |
3619 | counter = &memcg->memsw; |
3620 | break; | |
510fc4e1 | 3621 | case _KMEM: |
3e32cb2e | 3622 | counter = &memcg->kmem; |
510fc4e1 | 3623 | break; |
d55f90bf | 3624 | case _TCP: |
0db15298 | 3625 | counter = &memcg->tcpmem; |
d55f90bf | 3626 | break; |
8c7c6e34 KH |
3627 | default: |
3628 | BUG(); | |
8c7c6e34 | 3629 | } |
3e32cb2e JW |
3630 | |
3631 | switch (MEMFILE_ATTR(cft->private)) { | |
3632 | case RES_USAGE: | |
3633 | if (counter == &memcg->memory) | |
c12176d3 | 3634 | return (u64)mem_cgroup_usage(memcg, false) * PAGE_SIZE; |
3e32cb2e | 3635 | if (counter == &memcg->memsw) |
c12176d3 | 3636 | return (u64)mem_cgroup_usage(memcg, true) * PAGE_SIZE; |
3e32cb2e JW |
3637 | return (u64)page_counter_read(counter) * PAGE_SIZE; |
3638 | case RES_LIMIT: | |
bbec2e15 | 3639 | return (u64)counter->max * PAGE_SIZE; |
3e32cb2e JW |
3640 | case RES_MAX_USAGE: |
3641 | return (u64)counter->watermark * PAGE_SIZE; | |
3642 | case RES_FAILCNT: | |
3643 | return counter->failcnt; | |
3644 | case RES_SOFT_LIMIT: | |
3645 | return (u64)memcg->soft_limit * PAGE_SIZE; | |
3646 | default: | |
3647 | BUG(); | |
3648 | } | |
8cdea7c0 | 3649 | } |
510fc4e1 | 3650 | |
84c07d11 | 3651 | #ifdef CONFIG_MEMCG_KMEM |
567e9ab2 | 3652 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
d6441637 | 3653 | { |
bf4f0599 | 3654 | struct obj_cgroup *objcg; |
d6441637 | 3655 | |
9c94bef9 | 3656 | if (mem_cgroup_kmem_disabled()) |
b313aeee VD |
3657 | return 0; |
3658 | ||
da0efe30 MS |
3659 | if (unlikely(mem_cgroup_is_root(memcg))) |
3660 | return 0; | |
d6441637 | 3661 | |
bf4f0599 | 3662 | objcg = obj_cgroup_alloc(); |
f9c69d63 | 3663 | if (!objcg) |
bf4f0599 | 3664 | return -ENOMEM; |
f9c69d63 | 3665 | |
bf4f0599 RG |
3666 | objcg->memcg = memcg; |
3667 | rcu_assign_pointer(memcg->objcg, objcg); | |
3668 | ||
d648bcc7 RG |
3669 | static_branch_enable(&memcg_kmem_enabled_key); |
3670 | ||
f9c69d63 | 3671 | memcg->kmemcg_id = memcg->id.id; |
0b8f73e1 JW |
3672 | |
3673 | return 0; | |
d6441637 VD |
3674 | } |
3675 | ||
8e0a8912 JW |
3676 | static void memcg_offline_kmem(struct mem_cgroup *memcg) |
3677 | { | |
64268868 | 3678 | struct mem_cgroup *parent; |
8e0a8912 | 3679 | |
9c94bef9 | 3680 | if (mem_cgroup_kmem_disabled()) |
da0efe30 MS |
3681 | return; |
3682 | ||
3683 | if (unlikely(mem_cgroup_is_root(memcg))) | |
8e0a8912 | 3684 | return; |
9855609b | 3685 | |
8e0a8912 JW |
3686 | parent = parent_mem_cgroup(memcg); |
3687 | if (!parent) | |
3688 | parent = root_mem_cgroup; | |
3689 | ||
bf4f0599 | 3690 | memcg_reparent_objcgs(memcg, parent); |
fb2f2b0a | 3691 | |
8e0a8912 | 3692 | /* |
64268868 MS |
3693 | * After we have finished memcg_reparent_objcgs(), all list_lrus |
3694 | * corresponding to this cgroup are guaranteed to remain empty. | |
3695 | * The ordering is imposed by list_lru_node->lock taken by | |
1f391eb2 | 3696 | * memcg_reparent_list_lrus(). |
8e0a8912 | 3697 | */ |
1f391eb2 | 3698 | memcg_reparent_list_lrus(memcg, parent); |
8e0a8912 | 3699 | } |
d6441637 | 3700 | #else |
0b8f73e1 | 3701 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
127424c8 JW |
3702 | { |
3703 | return 0; | |
3704 | } | |
3705 | static void memcg_offline_kmem(struct mem_cgroup *memcg) | |
3706 | { | |
3707 | } | |
84c07d11 | 3708 | #endif /* CONFIG_MEMCG_KMEM */ |
127424c8 | 3709 | |
bbec2e15 | 3710 | static int memcg_update_tcp_max(struct mem_cgroup *memcg, unsigned long max) |
d55f90bf VD |
3711 | { |
3712 | int ret; | |
3713 | ||
bbec2e15 | 3714 | mutex_lock(&memcg_max_mutex); |
d55f90bf | 3715 | |
bbec2e15 | 3716 | ret = page_counter_set_max(&memcg->tcpmem, max); |
d55f90bf VD |
3717 | if (ret) |
3718 | goto out; | |
3719 | ||
0db15298 | 3720 | if (!memcg->tcpmem_active) { |
d55f90bf VD |
3721 | /* |
3722 | * The active flag needs to be written after the static_key | |
3723 | * update. This is what guarantees that the socket activation | |
2d758073 JW |
3724 | * function is the last one to run. See mem_cgroup_sk_alloc() |
3725 | * for details, and note that we don't mark any socket as | |
3726 | * belonging to this memcg until that flag is up. | |
d55f90bf VD |
3727 | * |
3728 | * We need to do this, because static_keys will span multiple | |
3729 | * sites, but we can't control their order. If we mark a socket | |
3730 | * as accounted, but the accounting functions are not patched in | |
3731 | * yet, we'll lose accounting. | |
3732 | * | |
2d758073 | 3733 | * We never race with the readers in mem_cgroup_sk_alloc(), |
d55f90bf VD |
3734 | * because when this value change, the code to process it is not |
3735 | * patched in yet. | |
3736 | */ | |
3737 | static_branch_inc(&memcg_sockets_enabled_key); | |
0db15298 | 3738 | memcg->tcpmem_active = true; |
d55f90bf VD |
3739 | } |
3740 | out: | |
bbec2e15 | 3741 | mutex_unlock(&memcg_max_mutex); |
d55f90bf VD |
3742 | return ret; |
3743 | } | |
d55f90bf | 3744 | |
628f4235 KH |
3745 | /* |
3746 | * The user of this function is... | |
3747 | * RES_LIMIT. | |
3748 | */ | |
451af504 TH |
3749 | static ssize_t mem_cgroup_write(struct kernfs_open_file *of, |
3750 | char *buf, size_t nbytes, loff_t off) | |
8cdea7c0 | 3751 | { |
451af504 | 3752 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 3753 | unsigned long nr_pages; |
628f4235 KH |
3754 | int ret; |
3755 | ||
451af504 | 3756 | buf = strstrip(buf); |
650c5e56 | 3757 | ret = page_counter_memparse(buf, "-1", &nr_pages); |
3e32cb2e JW |
3758 | if (ret) |
3759 | return ret; | |
af36f906 | 3760 | |
3e32cb2e | 3761 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
628f4235 | 3762 | case RES_LIMIT: |
4b3bde4c BS |
3763 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
3764 | ret = -EINVAL; | |
3765 | break; | |
3766 | } | |
3e32cb2e JW |
3767 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
3768 | case _MEM: | |
bbec2e15 | 3769 | ret = mem_cgroup_resize_max(memcg, nr_pages, false); |
8c7c6e34 | 3770 | break; |
3e32cb2e | 3771 | case _MEMSWAP: |
bbec2e15 | 3772 | ret = mem_cgroup_resize_max(memcg, nr_pages, true); |
296c81d8 | 3773 | break; |
3e32cb2e | 3774 | case _KMEM: |
58056f77 SB |
3775 | /* kmem.limit_in_bytes is deprecated. */ |
3776 | ret = -EOPNOTSUPP; | |
3e32cb2e | 3777 | break; |
d55f90bf | 3778 | case _TCP: |
bbec2e15 | 3779 | ret = memcg_update_tcp_max(memcg, nr_pages); |
d55f90bf | 3780 | break; |
3e32cb2e | 3781 | } |
296c81d8 | 3782 | break; |
3e32cb2e | 3783 | case RES_SOFT_LIMIT: |
2343e88d SAS |
3784 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) { |
3785 | ret = -EOPNOTSUPP; | |
3786 | } else { | |
3787 | memcg->soft_limit = nr_pages; | |
3788 | ret = 0; | |
3789 | } | |
628f4235 KH |
3790 | break; |
3791 | } | |
451af504 | 3792 | return ret ?: nbytes; |
8cdea7c0 BS |
3793 | } |
3794 | ||
6770c64e TH |
3795 | static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf, |
3796 | size_t nbytes, loff_t off) | |
c84872e1 | 3797 | { |
6770c64e | 3798 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 3799 | struct page_counter *counter; |
c84872e1 | 3800 | |
3e32cb2e JW |
3801 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
3802 | case _MEM: | |
3803 | counter = &memcg->memory; | |
3804 | break; | |
3805 | case _MEMSWAP: | |
3806 | counter = &memcg->memsw; | |
3807 | break; | |
3808 | case _KMEM: | |
3809 | counter = &memcg->kmem; | |
3810 | break; | |
d55f90bf | 3811 | case _TCP: |
0db15298 | 3812 | counter = &memcg->tcpmem; |
d55f90bf | 3813 | break; |
3e32cb2e JW |
3814 | default: |
3815 | BUG(); | |
3816 | } | |
af36f906 | 3817 | |
3e32cb2e | 3818 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
29f2a4da | 3819 | case RES_MAX_USAGE: |
3e32cb2e | 3820 | page_counter_reset_watermark(counter); |
29f2a4da PE |
3821 | break; |
3822 | case RES_FAILCNT: | |
3e32cb2e | 3823 | counter->failcnt = 0; |
29f2a4da | 3824 | break; |
3e32cb2e JW |
3825 | default: |
3826 | BUG(); | |
29f2a4da | 3827 | } |
f64c3f54 | 3828 | |
6770c64e | 3829 | return nbytes; |
c84872e1 PE |
3830 | } |
3831 | ||
182446d0 | 3832 | static u64 mem_cgroup_move_charge_read(struct cgroup_subsys_state *css, |
7dc74be0 DN |
3833 | struct cftype *cft) |
3834 | { | |
182446d0 | 3835 | return mem_cgroup_from_css(css)->move_charge_at_immigrate; |
7dc74be0 DN |
3836 | } |
3837 | ||
02491447 | 3838 | #ifdef CONFIG_MMU |
182446d0 | 3839 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
7dc74be0 DN |
3840 | struct cftype *cft, u64 val) |
3841 | { | |
182446d0 | 3842 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
7dc74be0 | 3843 | |
1dfab5ab | 3844 | if (val & ~MOVE_MASK) |
7dc74be0 | 3845 | return -EINVAL; |
ee5e8472 | 3846 | |
7dc74be0 | 3847 | /* |
ee5e8472 GC |
3848 | * No kind of locking is needed in here, because ->can_attach() will |
3849 | * check this value once in the beginning of the process, and then carry | |
3850 | * on with stale data. This means that changes to this value will only | |
3851 | * affect task migrations starting after the change. | |
7dc74be0 | 3852 | */ |
c0ff4b85 | 3853 | memcg->move_charge_at_immigrate = val; |
7dc74be0 DN |
3854 | return 0; |
3855 | } | |
02491447 | 3856 | #else |
182446d0 | 3857 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
02491447 DN |
3858 | struct cftype *cft, u64 val) |
3859 | { | |
3860 | return -ENOSYS; | |
3861 | } | |
3862 | #endif | |
7dc74be0 | 3863 | |
406eb0c9 | 3864 | #ifdef CONFIG_NUMA |
113b7dfd JW |
3865 | |
3866 | #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE)) | |
3867 | #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON)) | |
3868 | #define LRU_ALL ((1 << NR_LRU_LISTS) - 1) | |
3869 | ||
3870 | static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, | |
dd8657b6 | 3871 | int nid, unsigned int lru_mask, bool tree) |
113b7dfd | 3872 | { |
867e5e1d | 3873 | struct lruvec *lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); |
113b7dfd JW |
3874 | unsigned long nr = 0; |
3875 | enum lru_list lru; | |
3876 | ||
3877 | VM_BUG_ON((unsigned)nid >= nr_node_ids); | |
3878 | ||
3879 | for_each_lru(lru) { | |
3880 | if (!(BIT(lru) & lru_mask)) | |
3881 | continue; | |
dd8657b6 SB |
3882 | if (tree) |
3883 | nr += lruvec_page_state(lruvec, NR_LRU_BASE + lru); | |
3884 | else | |
3885 | nr += lruvec_page_state_local(lruvec, NR_LRU_BASE + lru); | |
113b7dfd JW |
3886 | } |
3887 | return nr; | |
3888 | } | |
3889 | ||
3890 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, | |
dd8657b6 SB |
3891 | unsigned int lru_mask, |
3892 | bool tree) | |
113b7dfd JW |
3893 | { |
3894 | unsigned long nr = 0; | |
3895 | enum lru_list lru; | |
3896 | ||
3897 | for_each_lru(lru) { | |
3898 | if (!(BIT(lru) & lru_mask)) | |
3899 | continue; | |
dd8657b6 SB |
3900 | if (tree) |
3901 | nr += memcg_page_state(memcg, NR_LRU_BASE + lru); | |
3902 | else | |
3903 | nr += memcg_page_state_local(memcg, NR_LRU_BASE + lru); | |
113b7dfd JW |
3904 | } |
3905 | return nr; | |
3906 | } | |
3907 | ||
2da8ca82 | 3908 | static int memcg_numa_stat_show(struct seq_file *m, void *v) |
406eb0c9 | 3909 | { |
25485de6 GT |
3910 | struct numa_stat { |
3911 | const char *name; | |
3912 | unsigned int lru_mask; | |
3913 | }; | |
3914 | ||
3915 | static const struct numa_stat stats[] = { | |
3916 | { "total", LRU_ALL }, | |
3917 | { "file", LRU_ALL_FILE }, | |
3918 | { "anon", LRU_ALL_ANON }, | |
3919 | { "unevictable", BIT(LRU_UNEVICTABLE) }, | |
3920 | }; | |
3921 | const struct numa_stat *stat; | |
406eb0c9 | 3922 | int nid; |
aa9694bb | 3923 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
406eb0c9 | 3924 | |
fd25a9e0 | 3925 | mem_cgroup_flush_stats(); |
2d146aa3 | 3926 | |
25485de6 | 3927 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
dd8657b6 SB |
3928 | seq_printf(m, "%s=%lu", stat->name, |
3929 | mem_cgroup_nr_lru_pages(memcg, stat->lru_mask, | |
3930 | false)); | |
3931 | for_each_node_state(nid, N_MEMORY) | |
3932 | seq_printf(m, " N%d=%lu", nid, | |
3933 | mem_cgroup_node_nr_lru_pages(memcg, nid, | |
3934 | stat->lru_mask, false)); | |
25485de6 | 3935 | seq_putc(m, '\n'); |
406eb0c9 | 3936 | } |
406eb0c9 | 3937 | |
071aee13 | 3938 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
dd8657b6 SB |
3939 | |
3940 | seq_printf(m, "hierarchical_%s=%lu", stat->name, | |
3941 | mem_cgroup_nr_lru_pages(memcg, stat->lru_mask, | |
3942 | true)); | |
3943 | for_each_node_state(nid, N_MEMORY) | |
3944 | seq_printf(m, " N%d=%lu", nid, | |
3945 | mem_cgroup_node_nr_lru_pages(memcg, nid, | |
3946 | stat->lru_mask, true)); | |
071aee13 | 3947 | seq_putc(m, '\n'); |
406eb0c9 | 3948 | } |
406eb0c9 | 3949 | |
406eb0c9 YH |
3950 | return 0; |
3951 | } | |
3952 | #endif /* CONFIG_NUMA */ | |
3953 | ||
c8713d0b | 3954 | static const unsigned int memcg1_stats[] = { |
0d1c2072 | 3955 | NR_FILE_PAGES, |
be5d0a74 | 3956 | NR_ANON_MAPPED, |
468c3982 JW |
3957 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
3958 | NR_ANON_THPS, | |
3959 | #endif | |
c8713d0b JW |
3960 | NR_SHMEM, |
3961 | NR_FILE_MAPPED, | |
3962 | NR_FILE_DIRTY, | |
3963 | NR_WRITEBACK, | |
3964 | MEMCG_SWAP, | |
3965 | }; | |
3966 | ||
3967 | static const char *const memcg1_stat_names[] = { | |
3968 | "cache", | |
3969 | "rss", | |
468c3982 | 3970 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
c8713d0b | 3971 | "rss_huge", |
468c3982 | 3972 | #endif |
c8713d0b JW |
3973 | "shmem", |
3974 | "mapped_file", | |
3975 | "dirty", | |
3976 | "writeback", | |
3977 | "swap", | |
3978 | }; | |
3979 | ||
df0e53d0 | 3980 | /* Universal VM events cgroup1 shows, original sort order */ |
8dd53fd3 | 3981 | static const unsigned int memcg1_events[] = { |
df0e53d0 JW |
3982 | PGPGIN, |
3983 | PGPGOUT, | |
3984 | PGFAULT, | |
3985 | PGMAJFAULT, | |
3986 | }; | |
3987 | ||
2da8ca82 | 3988 | static int memcg_stat_show(struct seq_file *m, void *v) |
d2ceb9b7 | 3989 | { |
aa9694bb | 3990 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
3e32cb2e | 3991 | unsigned long memory, memsw; |
af7c4b0e JW |
3992 | struct mem_cgroup *mi; |
3993 | unsigned int i; | |
406eb0c9 | 3994 | |
71cd3113 | 3995 | BUILD_BUG_ON(ARRAY_SIZE(memcg1_stat_names) != ARRAY_SIZE(memcg1_stats)); |
70bc068c | 3996 | |
fd25a9e0 | 3997 | mem_cgroup_flush_stats(); |
2d146aa3 | 3998 | |
71cd3113 | 3999 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
468c3982 JW |
4000 | unsigned long nr; |
4001 | ||
71cd3113 | 4002 | if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account()) |
1dd3a273 | 4003 | continue; |
468c3982 | 4004 | nr = memcg_page_state_local(memcg, memcg1_stats[i]); |
468c3982 | 4005 | seq_printf(m, "%s %lu\n", memcg1_stat_names[i], nr * PAGE_SIZE); |
1dd3a273 | 4006 | } |
7b854121 | 4007 | |
df0e53d0 | 4008 | for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) |
ebc5d83d | 4009 | seq_printf(m, "%s %lu\n", vm_event_name(memcg1_events[i]), |
205b20cc | 4010 | memcg_events_local(memcg, memcg1_events[i])); |
af7c4b0e JW |
4011 | |
4012 | for (i = 0; i < NR_LRU_LISTS; i++) | |
ebc5d83d | 4013 | seq_printf(m, "%s %lu\n", lru_list_name(i), |
205b20cc | 4014 | memcg_page_state_local(memcg, NR_LRU_BASE + i) * |
21d89d15 | 4015 | PAGE_SIZE); |
af7c4b0e | 4016 | |
14067bb3 | 4017 | /* Hierarchical information */ |
3e32cb2e JW |
4018 | memory = memsw = PAGE_COUNTER_MAX; |
4019 | for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) { | |
15b42562 CD |
4020 | memory = min(memory, READ_ONCE(mi->memory.max)); |
4021 | memsw = min(memsw, READ_ONCE(mi->memsw.max)); | |
fee7b548 | 4022 | } |
3e32cb2e JW |
4023 | seq_printf(m, "hierarchical_memory_limit %llu\n", |
4024 | (u64)memory * PAGE_SIZE); | |
7941d214 | 4025 | if (do_memsw_account()) |
3e32cb2e JW |
4026 | seq_printf(m, "hierarchical_memsw_limit %llu\n", |
4027 | (u64)memsw * PAGE_SIZE); | |
7f016ee8 | 4028 | |
8de7ecc6 | 4029 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
7de2e9f1 | 4030 | unsigned long nr; |
4031 | ||
71cd3113 | 4032 | if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account()) |
1dd3a273 | 4033 | continue; |
7de2e9f1 | 4034 | nr = memcg_page_state(memcg, memcg1_stats[i]); |
8de7ecc6 | 4035 | seq_printf(m, "total_%s %llu\n", memcg1_stat_names[i], |
7de2e9f1 | 4036 | (u64)nr * PAGE_SIZE); |
af7c4b0e JW |
4037 | } |
4038 | ||
8de7ecc6 | 4039 | for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) |
ebc5d83d KK |
4040 | seq_printf(m, "total_%s %llu\n", |
4041 | vm_event_name(memcg1_events[i]), | |
dd923990 | 4042 | (u64)memcg_events(memcg, memcg1_events[i])); |
af7c4b0e | 4043 | |
8de7ecc6 | 4044 | for (i = 0; i < NR_LRU_LISTS; i++) |
ebc5d83d | 4045 | seq_printf(m, "total_%s %llu\n", lru_list_name(i), |
42a30035 JW |
4046 | (u64)memcg_page_state(memcg, NR_LRU_BASE + i) * |
4047 | PAGE_SIZE); | |
14067bb3 | 4048 | |
7f016ee8 | 4049 | #ifdef CONFIG_DEBUG_VM |
7f016ee8 | 4050 | { |
ef8f2327 MG |
4051 | pg_data_t *pgdat; |
4052 | struct mem_cgroup_per_node *mz; | |
1431d4d1 JW |
4053 | unsigned long anon_cost = 0; |
4054 | unsigned long file_cost = 0; | |
7f016ee8 | 4055 | |
ef8f2327 | 4056 | for_each_online_pgdat(pgdat) { |
a3747b53 | 4057 | mz = memcg->nodeinfo[pgdat->node_id]; |
7f016ee8 | 4058 | |
1431d4d1 JW |
4059 | anon_cost += mz->lruvec.anon_cost; |
4060 | file_cost += mz->lruvec.file_cost; | |
ef8f2327 | 4061 | } |
1431d4d1 JW |
4062 | seq_printf(m, "anon_cost %lu\n", anon_cost); |
4063 | seq_printf(m, "file_cost %lu\n", file_cost); | |
7f016ee8 KM |
4064 | } |
4065 | #endif | |
4066 | ||
d2ceb9b7 KH |
4067 | return 0; |
4068 | } | |
4069 | ||
182446d0 TH |
4070 | static u64 mem_cgroup_swappiness_read(struct cgroup_subsys_state *css, |
4071 | struct cftype *cft) | |
a7885eb8 | 4072 | { |
182446d0 | 4073 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 4074 | |
1f4c025b | 4075 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
4076 | } |
4077 | ||
182446d0 TH |
4078 | static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, |
4079 | struct cftype *cft, u64 val) | |
a7885eb8 | 4080 | { |
182446d0 | 4081 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 4082 | |
37bc3cb9 | 4083 | if (val > 200) |
a7885eb8 KM |
4084 | return -EINVAL; |
4085 | ||
a4792030 | 4086 | if (!mem_cgroup_is_root(memcg)) |
3dae7fec JW |
4087 | memcg->swappiness = val; |
4088 | else | |
4089 | vm_swappiness = val; | |
068b38c1 | 4090 | |
a7885eb8 KM |
4091 | return 0; |
4092 | } | |
4093 | ||
2e72b634 KS |
4094 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
4095 | { | |
4096 | struct mem_cgroup_threshold_ary *t; | |
3e32cb2e | 4097 | unsigned long usage; |
2e72b634 KS |
4098 | int i; |
4099 | ||
4100 | rcu_read_lock(); | |
4101 | if (!swap) | |
2c488db2 | 4102 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 4103 | else |
2c488db2 | 4104 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
4105 | |
4106 | if (!t) | |
4107 | goto unlock; | |
4108 | ||
ce00a967 | 4109 | usage = mem_cgroup_usage(memcg, swap); |
2e72b634 KS |
4110 | |
4111 | /* | |
748dad36 | 4112 | * current_threshold points to threshold just below or equal to usage. |
2e72b634 KS |
4113 | * If it's not true, a threshold was crossed after last |
4114 | * call of __mem_cgroup_threshold(). | |
4115 | */ | |
5407a562 | 4116 | i = t->current_threshold; |
2e72b634 KS |
4117 | |
4118 | /* | |
4119 | * Iterate backward over array of thresholds starting from | |
4120 | * current_threshold and check if a threshold is crossed. | |
4121 | * If none of thresholds below usage is crossed, we read | |
4122 | * only one element of the array here. | |
4123 | */ | |
4124 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
4125 | eventfd_signal(t->entries[i].eventfd, 1); | |
4126 | ||
4127 | /* i = current_threshold + 1 */ | |
4128 | i++; | |
4129 | ||
4130 | /* | |
4131 | * Iterate forward over array of thresholds starting from | |
4132 | * current_threshold+1 and check if a threshold is crossed. | |
4133 | * If none of thresholds above usage is crossed, we read | |
4134 | * only one element of the array here. | |
4135 | */ | |
4136 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
4137 | eventfd_signal(t->entries[i].eventfd, 1); | |
4138 | ||
4139 | /* Update current_threshold */ | |
5407a562 | 4140 | t->current_threshold = i - 1; |
2e72b634 KS |
4141 | unlock: |
4142 | rcu_read_unlock(); | |
4143 | } | |
4144 | ||
4145 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
4146 | { | |
ad4ca5f4 KS |
4147 | while (memcg) { |
4148 | __mem_cgroup_threshold(memcg, false); | |
7941d214 | 4149 | if (do_memsw_account()) |
ad4ca5f4 KS |
4150 | __mem_cgroup_threshold(memcg, true); |
4151 | ||
4152 | memcg = parent_mem_cgroup(memcg); | |
4153 | } | |
2e72b634 KS |
4154 | } |
4155 | ||
4156 | static int compare_thresholds(const void *a, const void *b) | |
4157 | { | |
4158 | const struct mem_cgroup_threshold *_a = a; | |
4159 | const struct mem_cgroup_threshold *_b = b; | |
4160 | ||
2bff24a3 GT |
4161 | if (_a->threshold > _b->threshold) |
4162 | return 1; | |
4163 | ||
4164 | if (_a->threshold < _b->threshold) | |
4165 | return -1; | |
4166 | ||
4167 | return 0; | |
2e72b634 KS |
4168 | } |
4169 | ||
c0ff4b85 | 4170 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg) |
9490ff27 KH |
4171 | { |
4172 | struct mem_cgroup_eventfd_list *ev; | |
4173 | ||
2bcf2e92 MH |
4174 | spin_lock(&memcg_oom_lock); |
4175 | ||
c0ff4b85 | 4176 | list_for_each_entry(ev, &memcg->oom_notify, list) |
9490ff27 | 4177 | eventfd_signal(ev->eventfd, 1); |
2bcf2e92 MH |
4178 | |
4179 | spin_unlock(&memcg_oom_lock); | |
9490ff27 KH |
4180 | return 0; |
4181 | } | |
4182 | ||
c0ff4b85 | 4183 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) |
9490ff27 | 4184 | { |
7d74b06f KH |
4185 | struct mem_cgroup *iter; |
4186 | ||
c0ff4b85 | 4187 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 4188 | mem_cgroup_oom_notify_cb(iter); |
9490ff27 KH |
4189 | } |
4190 | ||
59b6f873 | 4191 | static int __mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 | 4192 | struct eventfd_ctx *eventfd, const char *args, enum res_type type) |
2e72b634 | 4193 | { |
2c488db2 KS |
4194 | struct mem_cgroup_thresholds *thresholds; |
4195 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e JW |
4196 | unsigned long threshold; |
4197 | unsigned long usage; | |
2c488db2 | 4198 | int i, size, ret; |
2e72b634 | 4199 | |
650c5e56 | 4200 | ret = page_counter_memparse(args, "-1", &threshold); |
2e72b634 KS |
4201 | if (ret) |
4202 | return ret; | |
4203 | ||
4204 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 4205 | |
05b84301 | 4206 | if (type == _MEM) { |
2c488db2 | 4207 | thresholds = &memcg->thresholds; |
ce00a967 | 4208 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 4209 | } else if (type == _MEMSWAP) { |
2c488db2 | 4210 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 4211 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 4212 | } else |
2e72b634 KS |
4213 | BUG(); |
4214 | ||
2e72b634 | 4215 | /* Check if a threshold crossed before adding a new one */ |
2c488db2 | 4216 | if (thresholds->primary) |
2e72b634 KS |
4217 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4218 | ||
2c488db2 | 4219 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
4220 | |
4221 | /* Allocate memory for new array of thresholds */ | |
67b8046f | 4222 | new = kmalloc(struct_size(new, entries, size), GFP_KERNEL); |
2c488db2 | 4223 | if (!new) { |
2e72b634 KS |
4224 | ret = -ENOMEM; |
4225 | goto unlock; | |
4226 | } | |
2c488db2 | 4227 | new->size = size; |
2e72b634 KS |
4228 | |
4229 | /* Copy thresholds (if any) to new array */ | |
e90342e6 GS |
4230 | if (thresholds->primary) |
4231 | memcpy(new->entries, thresholds->primary->entries, | |
4232 | flex_array_size(new, entries, size - 1)); | |
2c488db2 | 4233 | |
2e72b634 | 4234 | /* Add new threshold */ |
2c488db2 KS |
4235 | new->entries[size - 1].eventfd = eventfd; |
4236 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
4237 | |
4238 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
61e604e6 | 4239 | sort(new->entries, size, sizeof(*new->entries), |
2e72b634 KS |
4240 | compare_thresholds, NULL); |
4241 | ||
4242 | /* Find current threshold */ | |
2c488db2 | 4243 | new->current_threshold = -1; |
2e72b634 | 4244 | for (i = 0; i < size; i++) { |
748dad36 | 4245 | if (new->entries[i].threshold <= usage) { |
2e72b634 | 4246 | /* |
2c488db2 KS |
4247 | * new->current_threshold will not be used until |
4248 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
4249 | * it here. |
4250 | */ | |
2c488db2 | 4251 | ++new->current_threshold; |
748dad36 SZ |
4252 | } else |
4253 | break; | |
2e72b634 KS |
4254 | } |
4255 | ||
2c488db2 KS |
4256 | /* Free old spare buffer and save old primary buffer as spare */ |
4257 | kfree(thresholds->spare); | |
4258 | thresholds->spare = thresholds->primary; | |
4259 | ||
4260 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4261 | |
907860ed | 4262 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4263 | synchronize_rcu(); |
4264 | ||
2e72b634 KS |
4265 | unlock: |
4266 | mutex_unlock(&memcg->thresholds_lock); | |
4267 | ||
4268 | return ret; | |
4269 | } | |
4270 | ||
59b6f873 | 4271 | static int mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4272 | struct eventfd_ctx *eventfd, const char *args) |
4273 | { | |
59b6f873 | 4274 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEM); |
347c4a87 TH |
4275 | } |
4276 | ||
59b6f873 | 4277 | static int memsw_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4278 | struct eventfd_ctx *eventfd, const char *args) |
4279 | { | |
59b6f873 | 4280 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEMSWAP); |
347c4a87 TH |
4281 | } |
4282 | ||
59b6f873 | 4283 | static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 4284 | struct eventfd_ctx *eventfd, enum res_type type) |
2e72b634 | 4285 | { |
2c488db2 KS |
4286 | struct mem_cgroup_thresholds *thresholds; |
4287 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e | 4288 | unsigned long usage; |
7d36665a | 4289 | int i, j, size, entries; |
2e72b634 KS |
4290 | |
4291 | mutex_lock(&memcg->thresholds_lock); | |
05b84301 JW |
4292 | |
4293 | if (type == _MEM) { | |
2c488db2 | 4294 | thresholds = &memcg->thresholds; |
ce00a967 | 4295 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 4296 | } else if (type == _MEMSWAP) { |
2c488db2 | 4297 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 4298 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 4299 | } else |
2e72b634 KS |
4300 | BUG(); |
4301 | ||
371528ca AV |
4302 | if (!thresholds->primary) |
4303 | goto unlock; | |
4304 | ||
2e72b634 KS |
4305 | /* Check if a threshold crossed before removing */ |
4306 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
4307 | ||
4308 | /* Calculate new number of threshold */ | |
7d36665a | 4309 | size = entries = 0; |
2c488db2 KS |
4310 | for (i = 0; i < thresholds->primary->size; i++) { |
4311 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 | 4312 | size++; |
7d36665a CX |
4313 | else |
4314 | entries++; | |
2e72b634 KS |
4315 | } |
4316 | ||
2c488db2 | 4317 | new = thresholds->spare; |
907860ed | 4318 | |
7d36665a CX |
4319 | /* If no items related to eventfd have been cleared, nothing to do */ |
4320 | if (!entries) | |
4321 | goto unlock; | |
4322 | ||
2e72b634 KS |
4323 | /* Set thresholds array to NULL if we don't have thresholds */ |
4324 | if (!size) { | |
2c488db2 KS |
4325 | kfree(new); |
4326 | new = NULL; | |
907860ed | 4327 | goto swap_buffers; |
2e72b634 KS |
4328 | } |
4329 | ||
2c488db2 | 4330 | new->size = size; |
2e72b634 KS |
4331 | |
4332 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
4333 | new->current_threshold = -1; |
4334 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
4335 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
4336 | continue; |
4337 | ||
2c488db2 | 4338 | new->entries[j] = thresholds->primary->entries[i]; |
748dad36 | 4339 | if (new->entries[j].threshold <= usage) { |
2e72b634 | 4340 | /* |
2c488db2 | 4341 | * new->current_threshold will not be used |
2e72b634 KS |
4342 | * until rcu_assign_pointer(), so it's safe to increment |
4343 | * it here. | |
4344 | */ | |
2c488db2 | 4345 | ++new->current_threshold; |
2e72b634 KS |
4346 | } |
4347 | j++; | |
4348 | } | |
4349 | ||
907860ed | 4350 | swap_buffers: |
2c488db2 KS |
4351 | /* Swap primary and spare array */ |
4352 | thresholds->spare = thresholds->primary; | |
8c757763 | 4353 | |
2c488db2 | 4354 | rcu_assign_pointer(thresholds->primary, new); |
2e72b634 | 4355 | |
907860ed | 4356 | /* To be sure that nobody uses thresholds */ |
2e72b634 | 4357 | synchronize_rcu(); |
6611d8d7 MC |
4358 | |
4359 | /* If all events are unregistered, free the spare array */ | |
4360 | if (!new) { | |
4361 | kfree(thresholds->spare); | |
4362 | thresholds->spare = NULL; | |
4363 | } | |
371528ca | 4364 | unlock: |
2e72b634 | 4365 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 4366 | } |
c1e862c1 | 4367 | |
59b6f873 | 4368 | static void mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4369 | struct eventfd_ctx *eventfd) |
4370 | { | |
59b6f873 | 4371 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEM); |
347c4a87 TH |
4372 | } |
4373 | ||
59b6f873 | 4374 | static void memsw_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
4375 | struct eventfd_ctx *eventfd) |
4376 | { | |
59b6f873 | 4377 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEMSWAP); |
347c4a87 TH |
4378 | } |
4379 | ||
59b6f873 | 4380 | static int mem_cgroup_oom_register_event(struct mem_cgroup *memcg, |
347c4a87 | 4381 | struct eventfd_ctx *eventfd, const char *args) |
9490ff27 | 4382 | { |
9490ff27 | 4383 | struct mem_cgroup_eventfd_list *event; |
9490ff27 | 4384 | |
9490ff27 KH |
4385 | event = kmalloc(sizeof(*event), GFP_KERNEL); |
4386 | if (!event) | |
4387 | return -ENOMEM; | |
4388 | ||
1af8efe9 | 4389 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4390 | |
4391 | event->eventfd = eventfd; | |
4392 | list_add(&event->list, &memcg->oom_notify); | |
4393 | ||
4394 | /* already in OOM ? */ | |
c2b42d3c | 4395 | if (memcg->under_oom) |
9490ff27 | 4396 | eventfd_signal(eventfd, 1); |
1af8efe9 | 4397 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4398 | |
4399 | return 0; | |
4400 | } | |
4401 | ||
59b6f873 | 4402 | static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 4403 | struct eventfd_ctx *eventfd) |
9490ff27 | 4404 | { |
9490ff27 | 4405 | struct mem_cgroup_eventfd_list *ev, *tmp; |
9490ff27 | 4406 | |
1af8efe9 | 4407 | spin_lock(&memcg_oom_lock); |
9490ff27 | 4408 | |
c0ff4b85 | 4409 | list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) { |
9490ff27 KH |
4410 | if (ev->eventfd == eventfd) { |
4411 | list_del(&ev->list); | |
4412 | kfree(ev); | |
4413 | } | |
4414 | } | |
4415 | ||
1af8efe9 | 4416 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4417 | } |
4418 | ||
2da8ca82 | 4419 | static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v) |
3c11ecf4 | 4420 | { |
aa9694bb | 4421 | struct mem_cgroup *memcg = mem_cgroup_from_seq(sf); |
3c11ecf4 | 4422 | |
791badbd | 4423 | seq_printf(sf, "oom_kill_disable %d\n", memcg->oom_kill_disable); |
c2b42d3c | 4424 | seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom); |
fe6bdfc8 RG |
4425 | seq_printf(sf, "oom_kill %lu\n", |
4426 | atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL])); | |
3c11ecf4 KH |
4427 | return 0; |
4428 | } | |
4429 | ||
182446d0 | 4430 | static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css, |
3c11ecf4 KH |
4431 | struct cftype *cft, u64 val) |
4432 | { | |
182446d0 | 4433 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3c11ecf4 KH |
4434 | |
4435 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
a4792030 | 4436 | if (mem_cgroup_is_root(memcg) || !((val == 0) || (val == 1))) |
3c11ecf4 KH |
4437 | return -EINVAL; |
4438 | ||
c0ff4b85 | 4439 | memcg->oom_kill_disable = val; |
4d845ebf | 4440 | if (!val) |
c0ff4b85 | 4441 | memcg_oom_recover(memcg); |
3dae7fec | 4442 | |
3c11ecf4 KH |
4443 | return 0; |
4444 | } | |
4445 | ||
52ebea74 TH |
4446 | #ifdef CONFIG_CGROUP_WRITEBACK |
4447 | ||
3a8e9ac8 TH |
4448 | #include <trace/events/writeback.h> |
4449 | ||
841710aa TH |
4450 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) |
4451 | { | |
4452 | return wb_domain_init(&memcg->cgwb_domain, gfp); | |
4453 | } | |
4454 | ||
4455 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
4456 | { | |
4457 | wb_domain_exit(&memcg->cgwb_domain); | |
4458 | } | |
4459 | ||
2529bb3a TH |
4460 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
4461 | { | |
4462 | wb_domain_size_changed(&memcg->cgwb_domain); | |
4463 | } | |
4464 | ||
841710aa TH |
4465 | struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb) |
4466 | { | |
4467 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4468 | ||
4469 | if (!memcg->css.parent) | |
4470 | return NULL; | |
4471 | ||
4472 | return &memcg->cgwb_domain; | |
4473 | } | |
4474 | ||
c2aa723a TH |
4475 | /** |
4476 | * mem_cgroup_wb_stats - retrieve writeback related stats from its memcg | |
4477 | * @wb: bdi_writeback in question | |
c5edf9cd TH |
4478 | * @pfilepages: out parameter for number of file pages |
4479 | * @pheadroom: out parameter for number of allocatable pages according to memcg | |
c2aa723a TH |
4480 | * @pdirty: out parameter for number of dirty pages |
4481 | * @pwriteback: out parameter for number of pages under writeback | |
4482 | * | |
c5edf9cd TH |
4483 | * Determine the numbers of file, headroom, dirty, and writeback pages in |
4484 | * @wb's memcg. File, dirty and writeback are self-explanatory. Headroom | |
4485 | * is a bit more involved. | |
c2aa723a | 4486 | * |
c5edf9cd TH |
4487 | * A memcg's headroom is "min(max, high) - used". In the hierarchy, the |
4488 | * headroom is calculated as the lowest headroom of itself and the | |
4489 | * ancestors. Note that this doesn't consider the actual amount of | |
4490 | * available memory in the system. The caller should further cap | |
4491 | * *@pheadroom accordingly. | |
c2aa723a | 4492 | */ |
c5edf9cd TH |
4493 | void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, |
4494 | unsigned long *pheadroom, unsigned long *pdirty, | |
4495 | unsigned long *pwriteback) | |
c2aa723a TH |
4496 | { |
4497 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4498 | struct mem_cgroup *parent; | |
c2aa723a | 4499 | |
fd25a9e0 | 4500 | mem_cgroup_flush_stats(); |
c2aa723a | 4501 | |
2d146aa3 JW |
4502 | *pdirty = memcg_page_state(memcg, NR_FILE_DIRTY); |
4503 | *pwriteback = memcg_page_state(memcg, NR_WRITEBACK); | |
4504 | *pfilepages = memcg_page_state(memcg, NR_INACTIVE_FILE) + | |
4505 | memcg_page_state(memcg, NR_ACTIVE_FILE); | |
c2aa723a | 4506 | |
2d146aa3 | 4507 | *pheadroom = PAGE_COUNTER_MAX; |
c2aa723a | 4508 | while ((parent = parent_mem_cgroup(memcg))) { |
15b42562 | 4509 | unsigned long ceiling = min(READ_ONCE(memcg->memory.max), |
d1663a90 | 4510 | READ_ONCE(memcg->memory.high)); |
c2aa723a TH |
4511 | unsigned long used = page_counter_read(&memcg->memory); |
4512 | ||
c5edf9cd | 4513 | *pheadroom = min(*pheadroom, ceiling - min(ceiling, used)); |
c2aa723a TH |
4514 | memcg = parent; |
4515 | } | |
c2aa723a TH |
4516 | } |
4517 | ||
97b27821 TH |
4518 | /* |
4519 | * Foreign dirty flushing | |
4520 | * | |
4521 | * There's an inherent mismatch between memcg and writeback. The former | |
f0953a1b | 4522 | * tracks ownership per-page while the latter per-inode. This was a |
97b27821 TH |
4523 | * deliberate design decision because honoring per-page ownership in the |
4524 | * writeback path is complicated, may lead to higher CPU and IO overheads | |
4525 | * and deemed unnecessary given that write-sharing an inode across | |
4526 | * different cgroups isn't a common use-case. | |
4527 | * | |
4528 | * Combined with inode majority-writer ownership switching, this works well | |
4529 | * enough in most cases but there are some pathological cases. For | |
4530 | * example, let's say there are two cgroups A and B which keep writing to | |
4531 | * different but confined parts of the same inode. B owns the inode and | |
4532 | * A's memory is limited far below B's. A's dirty ratio can rise enough to | |
4533 | * trigger balance_dirty_pages() sleeps but B's can be low enough to avoid | |
4534 | * triggering background writeback. A will be slowed down without a way to | |
4535 | * make writeback of the dirty pages happen. | |
4536 | * | |
f0953a1b | 4537 | * Conditions like the above can lead to a cgroup getting repeatedly and |
97b27821 | 4538 | * severely throttled after making some progress after each |
f0953a1b | 4539 | * dirty_expire_interval while the underlying IO device is almost |
97b27821 TH |
4540 | * completely idle. |
4541 | * | |
4542 | * Solving this problem completely requires matching the ownership tracking | |
4543 | * granularities between memcg and writeback in either direction. However, | |
4544 | * the more egregious behaviors can be avoided by simply remembering the | |
4545 | * most recent foreign dirtying events and initiating remote flushes on | |
4546 | * them when local writeback isn't enough to keep the memory clean enough. | |
4547 | * | |
4548 | * The following two functions implement such mechanism. When a foreign | |
4549 | * page - a page whose memcg and writeback ownerships don't match - is | |
4550 | * dirtied, mem_cgroup_track_foreign_dirty() records the inode owning | |
4551 | * bdi_writeback on the page owning memcg. When balance_dirty_pages() | |
4552 | * decides that the memcg needs to sleep due to high dirty ratio, it calls | |
4553 | * mem_cgroup_flush_foreign() which queues writeback on the recorded | |
4554 | * foreign bdi_writebacks which haven't expired. Both the numbers of | |
4555 | * recorded bdi_writebacks and concurrent in-flight foreign writebacks are | |
4556 | * limited to MEMCG_CGWB_FRN_CNT. | |
4557 | * | |
4558 | * The mechanism only remembers IDs and doesn't hold any object references. | |
4559 | * As being wrong occasionally doesn't matter, updates and accesses to the | |
4560 | * records are lockless and racy. | |
4561 | */ | |
9d8053fc | 4562 | void mem_cgroup_track_foreign_dirty_slowpath(struct folio *folio, |
97b27821 TH |
4563 | struct bdi_writeback *wb) |
4564 | { | |
9d8053fc | 4565 | struct mem_cgroup *memcg = folio_memcg(folio); |
97b27821 TH |
4566 | struct memcg_cgwb_frn *frn; |
4567 | u64 now = get_jiffies_64(); | |
4568 | u64 oldest_at = now; | |
4569 | int oldest = -1; | |
4570 | int i; | |
4571 | ||
9d8053fc | 4572 | trace_track_foreign_dirty(folio, wb); |
3a8e9ac8 | 4573 | |
97b27821 TH |
4574 | /* |
4575 | * Pick the slot to use. If there is already a slot for @wb, keep | |
4576 | * using it. If not replace the oldest one which isn't being | |
4577 | * written out. | |
4578 | */ | |
4579 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) { | |
4580 | frn = &memcg->cgwb_frn[i]; | |
4581 | if (frn->bdi_id == wb->bdi->id && | |
4582 | frn->memcg_id == wb->memcg_css->id) | |
4583 | break; | |
4584 | if (time_before64(frn->at, oldest_at) && | |
4585 | atomic_read(&frn->done.cnt) == 1) { | |
4586 | oldest = i; | |
4587 | oldest_at = frn->at; | |
4588 | } | |
4589 | } | |
4590 | ||
4591 | if (i < MEMCG_CGWB_FRN_CNT) { | |
4592 | /* | |
4593 | * Re-using an existing one. Update timestamp lazily to | |
4594 | * avoid making the cacheline hot. We want them to be | |
4595 | * reasonably up-to-date and significantly shorter than | |
4596 | * dirty_expire_interval as that's what expires the record. | |
4597 | * Use the shorter of 1s and dirty_expire_interval / 8. | |
4598 | */ | |
4599 | unsigned long update_intv = | |
4600 | min_t(unsigned long, HZ, | |
4601 | msecs_to_jiffies(dirty_expire_interval * 10) / 8); | |
4602 | ||
4603 | if (time_before64(frn->at, now - update_intv)) | |
4604 | frn->at = now; | |
4605 | } else if (oldest >= 0) { | |
4606 | /* replace the oldest free one */ | |
4607 | frn = &memcg->cgwb_frn[oldest]; | |
4608 | frn->bdi_id = wb->bdi->id; | |
4609 | frn->memcg_id = wb->memcg_css->id; | |
4610 | frn->at = now; | |
4611 | } | |
4612 | } | |
4613 | ||
4614 | /* issue foreign writeback flushes for recorded foreign dirtying events */ | |
4615 | void mem_cgroup_flush_foreign(struct bdi_writeback *wb) | |
4616 | { | |
4617 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
4618 | unsigned long intv = msecs_to_jiffies(dirty_expire_interval * 10); | |
4619 | u64 now = jiffies_64; | |
4620 | int i; | |
4621 | ||
4622 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) { | |
4623 | struct memcg_cgwb_frn *frn = &memcg->cgwb_frn[i]; | |
4624 | ||
4625 | /* | |
4626 | * If the record is older than dirty_expire_interval, | |
4627 | * writeback on it has already started. No need to kick it | |
4628 | * off again. Also, don't start a new one if there's | |
4629 | * already one in flight. | |
4630 | */ | |
4631 | if (time_after64(frn->at, now - intv) && | |
4632 | atomic_read(&frn->done.cnt) == 1) { | |
4633 | frn->at = 0; | |
3a8e9ac8 | 4634 | trace_flush_foreign(wb, frn->bdi_id, frn->memcg_id); |
7490a2d2 | 4635 | cgroup_writeback_by_id(frn->bdi_id, frn->memcg_id, |
97b27821 TH |
4636 | WB_REASON_FOREIGN_FLUSH, |
4637 | &frn->done); | |
4638 | } | |
4639 | } | |
4640 | } | |
4641 | ||
841710aa TH |
4642 | #else /* CONFIG_CGROUP_WRITEBACK */ |
4643 | ||
4644 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) | |
4645 | { | |
4646 | return 0; | |
4647 | } | |
4648 | ||
4649 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
4650 | { | |
4651 | } | |
4652 | ||
2529bb3a TH |
4653 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
4654 | { | |
4655 | } | |
4656 | ||
52ebea74 TH |
4657 | #endif /* CONFIG_CGROUP_WRITEBACK */ |
4658 | ||
3bc942f3 TH |
4659 | /* |
4660 | * DO NOT USE IN NEW FILES. | |
4661 | * | |
4662 | * "cgroup.event_control" implementation. | |
4663 | * | |
4664 | * This is way over-engineered. It tries to support fully configurable | |
4665 | * events for each user. Such level of flexibility is completely | |
4666 | * unnecessary especially in the light of the planned unified hierarchy. | |
4667 | * | |
4668 | * Please deprecate this and replace with something simpler if at all | |
4669 | * possible. | |
4670 | */ | |
4671 | ||
79bd9814 TH |
4672 | /* |
4673 | * Unregister event and free resources. | |
4674 | * | |
4675 | * Gets called from workqueue. | |
4676 | */ | |
3bc942f3 | 4677 | static void memcg_event_remove(struct work_struct *work) |
79bd9814 | 4678 | { |
3bc942f3 TH |
4679 | struct mem_cgroup_event *event = |
4680 | container_of(work, struct mem_cgroup_event, remove); | |
59b6f873 | 4681 | struct mem_cgroup *memcg = event->memcg; |
79bd9814 TH |
4682 | |
4683 | remove_wait_queue(event->wqh, &event->wait); | |
4684 | ||
59b6f873 | 4685 | event->unregister_event(memcg, event->eventfd); |
79bd9814 TH |
4686 | |
4687 | /* Notify userspace the event is going away. */ | |
4688 | eventfd_signal(event->eventfd, 1); | |
4689 | ||
4690 | eventfd_ctx_put(event->eventfd); | |
4691 | kfree(event); | |
59b6f873 | 4692 | css_put(&memcg->css); |
79bd9814 TH |
4693 | } |
4694 | ||
4695 | /* | |
a9a08845 | 4696 | * Gets called on EPOLLHUP on eventfd when user closes it. |
79bd9814 TH |
4697 | * |
4698 | * Called with wqh->lock held and interrupts disabled. | |
4699 | */ | |
ac6424b9 | 4700 | static int memcg_event_wake(wait_queue_entry_t *wait, unsigned mode, |
3bc942f3 | 4701 | int sync, void *key) |
79bd9814 | 4702 | { |
3bc942f3 TH |
4703 | struct mem_cgroup_event *event = |
4704 | container_of(wait, struct mem_cgroup_event, wait); | |
59b6f873 | 4705 | struct mem_cgroup *memcg = event->memcg; |
3ad6f93e | 4706 | __poll_t flags = key_to_poll(key); |
79bd9814 | 4707 | |
a9a08845 | 4708 | if (flags & EPOLLHUP) { |
79bd9814 TH |
4709 | /* |
4710 | * If the event has been detached at cgroup removal, we | |
4711 | * can simply return knowing the other side will cleanup | |
4712 | * for us. | |
4713 | * | |
4714 | * We can't race against event freeing since the other | |
4715 | * side will require wqh->lock via remove_wait_queue(), | |
4716 | * which we hold. | |
4717 | */ | |
fba94807 | 4718 | spin_lock(&memcg->event_list_lock); |
79bd9814 TH |
4719 | if (!list_empty(&event->list)) { |
4720 | list_del_init(&event->list); | |
4721 | /* | |
4722 | * We are in atomic context, but cgroup_event_remove() | |
4723 | * may sleep, so we have to call it in workqueue. | |
4724 | */ | |
4725 | schedule_work(&event->remove); | |
4726 | } | |
fba94807 | 4727 | spin_unlock(&memcg->event_list_lock); |
79bd9814 TH |
4728 | } |
4729 | ||
4730 | return 0; | |
4731 | } | |
4732 | ||
3bc942f3 | 4733 | static void memcg_event_ptable_queue_proc(struct file *file, |
79bd9814 TH |
4734 | wait_queue_head_t *wqh, poll_table *pt) |
4735 | { | |
3bc942f3 TH |
4736 | struct mem_cgroup_event *event = |
4737 | container_of(pt, struct mem_cgroup_event, pt); | |
79bd9814 TH |
4738 | |
4739 | event->wqh = wqh; | |
4740 | add_wait_queue(wqh, &event->wait); | |
4741 | } | |
4742 | ||
4743 | /* | |
3bc942f3 TH |
4744 | * DO NOT USE IN NEW FILES. |
4745 | * | |
79bd9814 TH |
4746 | * Parse input and register new cgroup event handler. |
4747 | * | |
4748 | * Input must be in format '<event_fd> <control_fd> <args>'. | |
4749 | * Interpretation of args is defined by control file implementation. | |
4750 | */ | |
451af504 TH |
4751 | static ssize_t memcg_write_event_control(struct kernfs_open_file *of, |
4752 | char *buf, size_t nbytes, loff_t off) | |
79bd9814 | 4753 | { |
451af504 | 4754 | struct cgroup_subsys_state *css = of_css(of); |
fba94807 | 4755 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 4756 | struct mem_cgroup_event *event; |
79bd9814 TH |
4757 | struct cgroup_subsys_state *cfile_css; |
4758 | unsigned int efd, cfd; | |
4759 | struct fd efile; | |
4760 | struct fd cfile; | |
fba94807 | 4761 | const char *name; |
79bd9814 TH |
4762 | char *endp; |
4763 | int ret; | |
4764 | ||
2343e88d SAS |
4765 | if (IS_ENABLED(CONFIG_PREEMPT_RT)) |
4766 | return -EOPNOTSUPP; | |
4767 | ||
451af504 TH |
4768 | buf = strstrip(buf); |
4769 | ||
4770 | efd = simple_strtoul(buf, &endp, 10); | |
79bd9814 TH |
4771 | if (*endp != ' ') |
4772 | return -EINVAL; | |
451af504 | 4773 | buf = endp + 1; |
79bd9814 | 4774 | |
451af504 | 4775 | cfd = simple_strtoul(buf, &endp, 10); |
79bd9814 TH |
4776 | if ((*endp != ' ') && (*endp != '\0')) |
4777 | return -EINVAL; | |
451af504 | 4778 | buf = endp + 1; |
79bd9814 TH |
4779 | |
4780 | event = kzalloc(sizeof(*event), GFP_KERNEL); | |
4781 | if (!event) | |
4782 | return -ENOMEM; | |
4783 | ||
59b6f873 | 4784 | event->memcg = memcg; |
79bd9814 | 4785 | INIT_LIST_HEAD(&event->list); |
3bc942f3 TH |
4786 | init_poll_funcptr(&event->pt, memcg_event_ptable_queue_proc); |
4787 | init_waitqueue_func_entry(&event->wait, memcg_event_wake); | |
4788 | INIT_WORK(&event->remove, memcg_event_remove); | |
79bd9814 TH |
4789 | |
4790 | efile = fdget(efd); | |
4791 | if (!efile.file) { | |
4792 | ret = -EBADF; | |
4793 | goto out_kfree; | |
4794 | } | |
4795 | ||
4796 | event->eventfd = eventfd_ctx_fileget(efile.file); | |
4797 | if (IS_ERR(event->eventfd)) { | |
4798 | ret = PTR_ERR(event->eventfd); | |
4799 | goto out_put_efile; | |
4800 | } | |
4801 | ||
4802 | cfile = fdget(cfd); | |
4803 | if (!cfile.file) { | |
4804 | ret = -EBADF; | |
4805 | goto out_put_eventfd; | |
4806 | } | |
4807 | ||
4808 | /* the process need read permission on control file */ | |
4809 | /* AV: shouldn't we check that it's been opened for read instead? */ | |
02f92b38 | 4810 | ret = file_permission(cfile.file, MAY_READ); |
79bd9814 TH |
4811 | if (ret < 0) |
4812 | goto out_put_cfile; | |
4813 | ||
fba94807 TH |
4814 | /* |
4815 | * Determine the event callbacks and set them in @event. This used | |
4816 | * to be done via struct cftype but cgroup core no longer knows | |
4817 | * about these events. The following is crude but the whole thing | |
4818 | * is for compatibility anyway. | |
3bc942f3 TH |
4819 | * |
4820 | * DO NOT ADD NEW FILES. | |
fba94807 | 4821 | */ |
b583043e | 4822 | name = cfile.file->f_path.dentry->d_name.name; |
fba94807 TH |
4823 | |
4824 | if (!strcmp(name, "memory.usage_in_bytes")) { | |
4825 | event->register_event = mem_cgroup_usage_register_event; | |
4826 | event->unregister_event = mem_cgroup_usage_unregister_event; | |
4827 | } else if (!strcmp(name, "memory.oom_control")) { | |
4828 | event->register_event = mem_cgroup_oom_register_event; | |
4829 | event->unregister_event = mem_cgroup_oom_unregister_event; | |
4830 | } else if (!strcmp(name, "memory.pressure_level")) { | |
4831 | event->register_event = vmpressure_register_event; | |
4832 | event->unregister_event = vmpressure_unregister_event; | |
4833 | } else if (!strcmp(name, "memory.memsw.usage_in_bytes")) { | |
347c4a87 TH |
4834 | event->register_event = memsw_cgroup_usage_register_event; |
4835 | event->unregister_event = memsw_cgroup_usage_unregister_event; | |
fba94807 TH |
4836 | } else { |
4837 | ret = -EINVAL; | |
4838 | goto out_put_cfile; | |
4839 | } | |
4840 | ||
79bd9814 | 4841 | /* |
b5557c4c TH |
4842 | * Verify @cfile should belong to @css. Also, remaining events are |
4843 | * automatically removed on cgroup destruction but the removal is | |
4844 | * asynchronous, so take an extra ref on @css. | |
79bd9814 | 4845 | */ |
b583043e | 4846 | cfile_css = css_tryget_online_from_dir(cfile.file->f_path.dentry->d_parent, |
ec903c0c | 4847 | &memory_cgrp_subsys); |
79bd9814 | 4848 | ret = -EINVAL; |
5a17f543 | 4849 | if (IS_ERR(cfile_css)) |
79bd9814 | 4850 | goto out_put_cfile; |
5a17f543 TH |
4851 | if (cfile_css != css) { |
4852 | css_put(cfile_css); | |
79bd9814 | 4853 | goto out_put_cfile; |
5a17f543 | 4854 | } |
79bd9814 | 4855 | |
451af504 | 4856 | ret = event->register_event(memcg, event->eventfd, buf); |
79bd9814 TH |
4857 | if (ret) |
4858 | goto out_put_css; | |
4859 | ||
9965ed17 | 4860 | vfs_poll(efile.file, &event->pt); |
79bd9814 | 4861 | |
4ba9515d | 4862 | spin_lock_irq(&memcg->event_list_lock); |
fba94807 | 4863 | list_add(&event->list, &memcg->event_list); |
4ba9515d | 4864 | spin_unlock_irq(&memcg->event_list_lock); |
79bd9814 TH |
4865 | |
4866 | fdput(cfile); | |
4867 | fdput(efile); | |
4868 | ||
451af504 | 4869 | return nbytes; |
79bd9814 TH |
4870 | |
4871 | out_put_css: | |
b5557c4c | 4872 | css_put(css); |
79bd9814 TH |
4873 | out_put_cfile: |
4874 | fdput(cfile); | |
4875 | out_put_eventfd: | |
4876 | eventfd_ctx_put(event->eventfd); | |
4877 | out_put_efile: | |
4878 | fdput(efile); | |
4879 | out_kfree: | |
4880 | kfree(event); | |
4881 | ||
4882 | return ret; | |
4883 | } | |
4884 | ||
c29b5b3d MS |
4885 | #if defined(CONFIG_MEMCG_KMEM) && (defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)) |
4886 | static int mem_cgroup_slab_show(struct seq_file *m, void *p) | |
4887 | { | |
4888 | /* | |
4889 | * Deprecated. | |
df4ae285 | 4890 | * Please, take a look at tools/cgroup/memcg_slabinfo.py . |
c29b5b3d MS |
4891 | */ |
4892 | return 0; | |
4893 | } | |
4894 | #endif | |
4895 | ||
241994ed | 4896 | static struct cftype mem_cgroup_legacy_files[] = { |
8cdea7c0 | 4897 | { |
0eea1030 | 4898 | .name = "usage_in_bytes", |
8c7c6e34 | 4899 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
791badbd | 4900 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 4901 | }, |
c84872e1 PE |
4902 | { |
4903 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 4904 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
6770c64e | 4905 | .write = mem_cgroup_reset, |
791badbd | 4906 | .read_u64 = mem_cgroup_read_u64, |
c84872e1 | 4907 | }, |
8cdea7c0 | 4908 | { |
0eea1030 | 4909 | .name = "limit_in_bytes", |
8c7c6e34 | 4910 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
451af504 | 4911 | .write = mem_cgroup_write, |
791badbd | 4912 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 4913 | }, |
296c81d8 BS |
4914 | { |
4915 | .name = "soft_limit_in_bytes", | |
4916 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
451af504 | 4917 | .write = mem_cgroup_write, |
791badbd | 4918 | .read_u64 = mem_cgroup_read_u64, |
296c81d8 | 4919 | }, |
8cdea7c0 BS |
4920 | { |
4921 | .name = "failcnt", | |
8c7c6e34 | 4922 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
6770c64e | 4923 | .write = mem_cgroup_reset, |
791badbd | 4924 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 4925 | }, |
d2ceb9b7 KH |
4926 | { |
4927 | .name = "stat", | |
2da8ca82 | 4928 | .seq_show = memcg_stat_show, |
d2ceb9b7 | 4929 | }, |
c1e862c1 KH |
4930 | { |
4931 | .name = "force_empty", | |
6770c64e | 4932 | .write = mem_cgroup_force_empty_write, |
c1e862c1 | 4933 | }, |
18f59ea7 BS |
4934 | { |
4935 | .name = "use_hierarchy", | |
4936 | .write_u64 = mem_cgroup_hierarchy_write, | |
4937 | .read_u64 = mem_cgroup_hierarchy_read, | |
4938 | }, | |
79bd9814 | 4939 | { |
3bc942f3 | 4940 | .name = "cgroup.event_control", /* XXX: for compat */ |
451af504 | 4941 | .write = memcg_write_event_control, |
7dbdb199 | 4942 | .flags = CFTYPE_NO_PREFIX | CFTYPE_WORLD_WRITABLE, |
79bd9814 | 4943 | }, |
a7885eb8 KM |
4944 | { |
4945 | .name = "swappiness", | |
4946 | .read_u64 = mem_cgroup_swappiness_read, | |
4947 | .write_u64 = mem_cgroup_swappiness_write, | |
4948 | }, | |
7dc74be0 DN |
4949 | { |
4950 | .name = "move_charge_at_immigrate", | |
4951 | .read_u64 = mem_cgroup_move_charge_read, | |
4952 | .write_u64 = mem_cgroup_move_charge_write, | |
4953 | }, | |
9490ff27 KH |
4954 | { |
4955 | .name = "oom_control", | |
2da8ca82 | 4956 | .seq_show = mem_cgroup_oom_control_read, |
3c11ecf4 | 4957 | .write_u64 = mem_cgroup_oom_control_write, |
9490ff27 | 4958 | }, |
70ddf637 AV |
4959 | { |
4960 | .name = "pressure_level", | |
70ddf637 | 4961 | }, |
406eb0c9 YH |
4962 | #ifdef CONFIG_NUMA |
4963 | { | |
4964 | .name = "numa_stat", | |
2da8ca82 | 4965 | .seq_show = memcg_numa_stat_show, |
406eb0c9 YH |
4966 | }, |
4967 | #endif | |
510fc4e1 GC |
4968 | { |
4969 | .name = "kmem.limit_in_bytes", | |
4970 | .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT), | |
451af504 | 4971 | .write = mem_cgroup_write, |
791badbd | 4972 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
4973 | }, |
4974 | { | |
4975 | .name = "kmem.usage_in_bytes", | |
4976 | .private = MEMFILE_PRIVATE(_KMEM, RES_USAGE), | |
791badbd | 4977 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
4978 | }, |
4979 | { | |
4980 | .name = "kmem.failcnt", | |
4981 | .private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT), | |
6770c64e | 4982 | .write = mem_cgroup_reset, |
791badbd | 4983 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
4984 | }, |
4985 | { | |
4986 | .name = "kmem.max_usage_in_bytes", | |
4987 | .private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE), | |
6770c64e | 4988 | .write = mem_cgroup_reset, |
791badbd | 4989 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 | 4990 | }, |
a87425a3 YS |
4991 | #if defined(CONFIG_MEMCG_KMEM) && \ |
4992 | (defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)) | |
749c5415 GC |
4993 | { |
4994 | .name = "kmem.slabinfo", | |
c29b5b3d | 4995 | .seq_show = mem_cgroup_slab_show, |
749c5415 GC |
4996 | }, |
4997 | #endif | |
d55f90bf VD |
4998 | { |
4999 | .name = "kmem.tcp.limit_in_bytes", | |
5000 | .private = MEMFILE_PRIVATE(_TCP, RES_LIMIT), | |
5001 | .write = mem_cgroup_write, | |
5002 | .read_u64 = mem_cgroup_read_u64, | |
5003 | }, | |
5004 | { | |
5005 | .name = "kmem.tcp.usage_in_bytes", | |
5006 | .private = MEMFILE_PRIVATE(_TCP, RES_USAGE), | |
5007 | .read_u64 = mem_cgroup_read_u64, | |
5008 | }, | |
5009 | { | |
5010 | .name = "kmem.tcp.failcnt", | |
5011 | .private = MEMFILE_PRIVATE(_TCP, RES_FAILCNT), | |
5012 | .write = mem_cgroup_reset, | |
5013 | .read_u64 = mem_cgroup_read_u64, | |
5014 | }, | |
5015 | { | |
5016 | .name = "kmem.tcp.max_usage_in_bytes", | |
5017 | .private = MEMFILE_PRIVATE(_TCP, RES_MAX_USAGE), | |
5018 | .write = mem_cgroup_reset, | |
5019 | .read_u64 = mem_cgroup_read_u64, | |
5020 | }, | |
6bc10349 | 5021 | { }, /* terminate */ |
af36f906 | 5022 | }; |
8c7c6e34 | 5023 | |
73f576c0 JW |
5024 | /* |
5025 | * Private memory cgroup IDR | |
5026 | * | |
5027 | * Swap-out records and page cache shadow entries need to store memcg | |
5028 | * references in constrained space, so we maintain an ID space that is | |
5029 | * limited to 16 bit (MEM_CGROUP_ID_MAX), limiting the total number of | |
5030 | * memory-controlled cgroups to 64k. | |
5031 | * | |
b8f2935f | 5032 | * However, there usually are many references to the offline CSS after |
73f576c0 JW |
5033 | * the cgroup has been destroyed, such as page cache or reclaimable |
5034 | * slab objects, that don't need to hang on to the ID. We want to keep | |
5035 | * those dead CSS from occupying IDs, or we might quickly exhaust the | |
5036 | * relatively small ID space and prevent the creation of new cgroups | |
5037 | * even when there are much fewer than 64k cgroups - possibly none. | |
5038 | * | |
5039 | * Maintain a private 16-bit ID space for memcg, and allow the ID to | |
5040 | * be freed and recycled when it's no longer needed, which is usually | |
5041 | * when the CSS is offlined. | |
5042 | * | |
5043 | * The only exception to that are records of swapped out tmpfs/shmem | |
5044 | * pages that need to be attributed to live ancestors on swapin. But | |
5045 | * those references are manageable from userspace. | |
5046 | */ | |
5047 | ||
5048 | static DEFINE_IDR(mem_cgroup_idr); | |
5049 | ||
7e97de0b KT |
5050 | static void mem_cgroup_id_remove(struct mem_cgroup *memcg) |
5051 | { | |
5052 | if (memcg->id.id > 0) { | |
5053 | idr_remove(&mem_cgroup_idr, memcg->id.id); | |
5054 | memcg->id.id = 0; | |
5055 | } | |
5056 | } | |
5057 | ||
c1514c0a VF |
5058 | static void __maybe_unused mem_cgroup_id_get_many(struct mem_cgroup *memcg, |
5059 | unsigned int n) | |
73f576c0 | 5060 | { |
1c2d479a | 5061 | refcount_add(n, &memcg->id.ref); |
73f576c0 JW |
5062 | } |
5063 | ||
615d66c3 | 5064 | static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n) |
73f576c0 | 5065 | { |
1c2d479a | 5066 | if (refcount_sub_and_test(n, &memcg->id.ref)) { |
7e97de0b | 5067 | mem_cgroup_id_remove(memcg); |
73f576c0 JW |
5068 | |
5069 | /* Memcg ID pins CSS */ | |
5070 | css_put(&memcg->css); | |
5071 | } | |
5072 | } | |
5073 | ||
615d66c3 VD |
5074 | static inline void mem_cgroup_id_put(struct mem_cgroup *memcg) |
5075 | { | |
5076 | mem_cgroup_id_put_many(memcg, 1); | |
5077 | } | |
5078 | ||
73f576c0 JW |
5079 | /** |
5080 | * mem_cgroup_from_id - look up a memcg from a memcg id | |
5081 | * @id: the memcg id to look up | |
5082 | * | |
5083 | * Caller must hold rcu_read_lock(). | |
5084 | */ | |
5085 | struct mem_cgroup *mem_cgroup_from_id(unsigned short id) | |
5086 | { | |
5087 | WARN_ON_ONCE(!rcu_read_lock_held()); | |
5088 | return idr_find(&mem_cgroup_idr, id); | |
5089 | } | |
5090 | ||
c15187a4 RG |
5091 | #ifdef CONFIG_SHRINKER_DEBUG |
5092 | struct mem_cgroup *mem_cgroup_get_from_ino(unsigned long ino) | |
5093 | { | |
5094 | struct cgroup *cgrp; | |
5095 | struct cgroup_subsys_state *css; | |
5096 | struct mem_cgroup *memcg; | |
5097 | ||
5098 | cgrp = cgroup_get_from_id(ino); | |
5099 | if (!cgrp) | |
5100 | return ERR_PTR(-ENOENT); | |
5101 | ||
5102 | css = cgroup_get_e_css(cgrp, &memory_cgrp_subsys); | |
5103 | if (css) | |
5104 | memcg = container_of(css, struct mem_cgroup, css); | |
5105 | else | |
5106 | memcg = ERR_PTR(-ENOENT); | |
5107 | ||
5108 | cgroup_put(cgrp); | |
5109 | ||
5110 | return memcg; | |
5111 | } | |
5112 | #endif | |
5113 | ||
ef8f2327 | 5114 | static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) |
6d12e2d8 KH |
5115 | { |
5116 | struct mem_cgroup_per_node *pn; | |
8c9bb398 WY |
5117 | |
5118 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, node); | |
6d12e2d8 KH |
5119 | if (!pn) |
5120 | return 1; | |
1ecaab2b | 5121 | |
7e1c0d6f SB |
5122 | pn->lruvec_stats_percpu = alloc_percpu_gfp(struct lruvec_stats_percpu, |
5123 | GFP_KERNEL_ACCOUNT); | |
5124 | if (!pn->lruvec_stats_percpu) { | |
00f3ca2c JW |
5125 | kfree(pn); |
5126 | return 1; | |
5127 | } | |
5128 | ||
ef8f2327 | 5129 | lruvec_init(&pn->lruvec); |
ef8f2327 MG |
5130 | pn->memcg = memcg; |
5131 | ||
54f72fe0 | 5132 | memcg->nodeinfo[node] = pn; |
6d12e2d8 KH |
5133 | return 0; |
5134 | } | |
5135 | ||
ef8f2327 | 5136 | static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) |
1ecaab2b | 5137 | { |
00f3ca2c JW |
5138 | struct mem_cgroup_per_node *pn = memcg->nodeinfo[node]; |
5139 | ||
4eaf431f MH |
5140 | if (!pn) |
5141 | return; | |
5142 | ||
7e1c0d6f | 5143 | free_percpu(pn->lruvec_stats_percpu); |
00f3ca2c | 5144 | kfree(pn); |
1ecaab2b KH |
5145 | } |
5146 | ||
40e952f9 | 5147 | static void __mem_cgroup_free(struct mem_cgroup *memcg) |
59927fb9 | 5148 | { |
c8b2a36f | 5149 | int node; |
59927fb9 | 5150 | |
c8b2a36f | 5151 | for_each_node(node) |
ef8f2327 | 5152 | free_mem_cgroup_per_node_info(memcg, node); |
871789d4 | 5153 | free_percpu(memcg->vmstats_percpu); |
8ff69e2c | 5154 | kfree(memcg); |
59927fb9 | 5155 | } |
3afe36b1 | 5156 | |
40e952f9 TE |
5157 | static void mem_cgroup_free(struct mem_cgroup *memcg) |
5158 | { | |
5159 | memcg_wb_domain_exit(memcg); | |
5160 | __mem_cgroup_free(memcg); | |
5161 | } | |
5162 | ||
0b8f73e1 | 5163 | static struct mem_cgroup *mem_cgroup_alloc(void) |
8cdea7c0 | 5164 | { |
d142e3e6 | 5165 | struct mem_cgroup *memcg; |
6d12e2d8 | 5166 | int node; |
97b27821 | 5167 | int __maybe_unused i; |
11d67612 | 5168 | long error = -ENOMEM; |
8cdea7c0 | 5169 | |
06b2c3b0 | 5170 | memcg = kzalloc(struct_size(memcg, nodeinfo, nr_node_ids), GFP_KERNEL); |
c0ff4b85 | 5171 | if (!memcg) |
11d67612 | 5172 | return ERR_PTR(error); |
0b8f73e1 | 5173 | |
73f576c0 | 5174 | memcg->id.id = idr_alloc(&mem_cgroup_idr, NULL, |
be740503 | 5175 | 1, MEM_CGROUP_ID_MAX + 1, GFP_KERNEL); |
11d67612 YS |
5176 | if (memcg->id.id < 0) { |
5177 | error = memcg->id.id; | |
73f576c0 | 5178 | goto fail; |
11d67612 | 5179 | } |
73f576c0 | 5180 | |
3e38e0aa RG |
5181 | memcg->vmstats_percpu = alloc_percpu_gfp(struct memcg_vmstats_percpu, |
5182 | GFP_KERNEL_ACCOUNT); | |
871789d4 | 5183 | if (!memcg->vmstats_percpu) |
0b8f73e1 | 5184 | goto fail; |
78fb7466 | 5185 | |
3ed28fa1 | 5186 | for_each_node(node) |
ef8f2327 | 5187 | if (alloc_mem_cgroup_per_node_info(memcg, node)) |
0b8f73e1 | 5188 | goto fail; |
f64c3f54 | 5189 | |
0b8f73e1 JW |
5190 | if (memcg_wb_domain_init(memcg, GFP_KERNEL)) |
5191 | goto fail; | |
28dbc4b6 | 5192 | |
f7e1cb6e | 5193 | INIT_WORK(&memcg->high_work, high_work_func); |
d142e3e6 | 5194 | INIT_LIST_HEAD(&memcg->oom_notify); |
d142e3e6 GC |
5195 | mutex_init(&memcg->thresholds_lock); |
5196 | spin_lock_init(&memcg->move_lock); | |
70ddf637 | 5197 | vmpressure_init(&memcg->vmpressure); |
fba94807 TH |
5198 | INIT_LIST_HEAD(&memcg->event_list); |
5199 | spin_lock_init(&memcg->event_list_lock); | |
d886f4e4 | 5200 | memcg->socket_pressure = jiffies; |
84c07d11 | 5201 | #ifdef CONFIG_MEMCG_KMEM |
900a38f0 | 5202 | memcg->kmemcg_id = -1; |
bf4f0599 | 5203 | INIT_LIST_HEAD(&memcg->objcg_list); |
900a38f0 | 5204 | #endif |
52ebea74 TH |
5205 | #ifdef CONFIG_CGROUP_WRITEBACK |
5206 | INIT_LIST_HEAD(&memcg->cgwb_list); | |
97b27821 TH |
5207 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) |
5208 | memcg->cgwb_frn[i].done = | |
5209 | __WB_COMPLETION_INIT(&memcg_cgwb_frn_waitq); | |
87eaceb3 YS |
5210 | #endif |
5211 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
5212 | spin_lock_init(&memcg->deferred_split_queue.split_queue_lock); | |
5213 | INIT_LIST_HEAD(&memcg->deferred_split_queue.split_queue); | |
5214 | memcg->deferred_split_queue.split_queue_len = 0; | |
52ebea74 | 5215 | #endif |
73f576c0 | 5216 | idr_replace(&mem_cgroup_idr, memcg, memcg->id.id); |
0b8f73e1 JW |
5217 | return memcg; |
5218 | fail: | |
7e97de0b | 5219 | mem_cgroup_id_remove(memcg); |
40e952f9 | 5220 | __mem_cgroup_free(memcg); |
11d67612 | 5221 | return ERR_PTR(error); |
d142e3e6 GC |
5222 | } |
5223 | ||
0b8f73e1 JW |
5224 | static struct cgroup_subsys_state * __ref |
5225 | mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
d142e3e6 | 5226 | { |
0b8f73e1 | 5227 | struct mem_cgroup *parent = mem_cgroup_from_css(parent_css); |
b87d8cef | 5228 | struct mem_cgroup *memcg, *old_memcg; |
d142e3e6 | 5229 | |
b87d8cef | 5230 | old_memcg = set_active_memcg(parent); |
0b8f73e1 | 5231 | memcg = mem_cgroup_alloc(); |
b87d8cef | 5232 | set_active_memcg(old_memcg); |
11d67612 YS |
5233 | if (IS_ERR(memcg)) |
5234 | return ERR_CAST(memcg); | |
d142e3e6 | 5235 | |
d1663a90 | 5236 | page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX); |
0b8f73e1 | 5237 | memcg->soft_limit = PAGE_COUNTER_MAX; |
f4840ccf JW |
5238 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
5239 | memcg->zswap_max = PAGE_COUNTER_MAX; | |
5240 | #endif | |
4b82ab4f | 5241 | page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX); |
0b8f73e1 JW |
5242 | if (parent) { |
5243 | memcg->swappiness = mem_cgroup_swappiness(parent); | |
5244 | memcg->oom_kill_disable = parent->oom_kill_disable; | |
bef8620c | 5245 | |
3e32cb2e | 5246 | page_counter_init(&memcg->memory, &parent->memory); |
37e84351 | 5247 | page_counter_init(&memcg->swap, &parent->swap); |
3e32cb2e | 5248 | page_counter_init(&memcg->kmem, &parent->kmem); |
0db15298 | 5249 | page_counter_init(&memcg->tcpmem, &parent->tcpmem); |
18f59ea7 | 5250 | } else { |
bef8620c RG |
5251 | page_counter_init(&memcg->memory, NULL); |
5252 | page_counter_init(&memcg->swap, NULL); | |
5253 | page_counter_init(&memcg->kmem, NULL); | |
5254 | page_counter_init(&memcg->tcpmem, NULL); | |
d6441637 | 5255 | |
0b8f73e1 JW |
5256 | root_mem_cgroup = memcg; |
5257 | return &memcg->css; | |
5258 | } | |
5259 | ||
f7e1cb6e | 5260 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 5261 | static_branch_inc(&memcg_sockets_enabled_key); |
f7e1cb6e | 5262 | |
0b8f73e1 | 5263 | return &memcg->css; |
0b8f73e1 JW |
5264 | } |
5265 | ||
73f576c0 | 5266 | static int mem_cgroup_css_online(struct cgroup_subsys_state *css) |
0b8f73e1 | 5267 | { |
58fa2a55 VD |
5268 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
5269 | ||
da0efe30 MS |
5270 | if (memcg_online_kmem(memcg)) |
5271 | goto remove_id; | |
5272 | ||
0a4465d3 | 5273 | /* |
e4262c4f | 5274 | * A memcg must be visible for expand_shrinker_info() |
0a4465d3 KT |
5275 | * by the time the maps are allocated. So, we allocate maps |
5276 | * here, when for_each_mem_cgroup() can't skip it. | |
5277 | */ | |
da0efe30 MS |
5278 | if (alloc_shrinker_info(memcg)) |
5279 | goto offline_kmem; | |
0a4465d3 | 5280 | |
73f576c0 | 5281 | /* Online state pins memcg ID, memcg ID pins CSS */ |
1c2d479a | 5282 | refcount_set(&memcg->id.ref, 1); |
73f576c0 | 5283 | css_get(css); |
aa48e47e SB |
5284 | |
5285 | if (unlikely(mem_cgroup_is_root(memcg))) | |
5286 | queue_delayed_work(system_unbound_wq, &stats_flush_dwork, | |
5287 | 2UL*HZ); | |
2f7dd7a4 | 5288 | return 0; |
da0efe30 MS |
5289 | offline_kmem: |
5290 | memcg_offline_kmem(memcg); | |
5291 | remove_id: | |
5292 | mem_cgroup_id_remove(memcg); | |
5293 | return -ENOMEM; | |
8cdea7c0 BS |
5294 | } |
5295 | ||
eb95419b | 5296 | static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) |
df878fb0 | 5297 | { |
eb95419b | 5298 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 5299 | struct mem_cgroup_event *event, *tmp; |
79bd9814 TH |
5300 | |
5301 | /* | |
5302 | * Unregister events and notify userspace. | |
5303 | * Notify userspace about cgroup removing only after rmdir of cgroup | |
5304 | * directory to avoid race between userspace and kernelspace. | |
5305 | */ | |
4ba9515d | 5306 | spin_lock_irq(&memcg->event_list_lock); |
fba94807 | 5307 | list_for_each_entry_safe(event, tmp, &memcg->event_list, list) { |
79bd9814 TH |
5308 | list_del_init(&event->list); |
5309 | schedule_work(&event->remove); | |
5310 | } | |
4ba9515d | 5311 | spin_unlock_irq(&memcg->event_list_lock); |
ec64f515 | 5312 | |
bf8d5d52 | 5313 | page_counter_set_min(&memcg->memory, 0); |
23067153 | 5314 | page_counter_set_low(&memcg->memory, 0); |
63677c74 | 5315 | |
567e9ab2 | 5316 | memcg_offline_kmem(memcg); |
a178015c | 5317 | reparent_shrinker_deferred(memcg); |
52ebea74 | 5318 | wb_memcg_offline(memcg); |
73f576c0 | 5319 | |
591edfb1 RG |
5320 | drain_all_stock(memcg); |
5321 | ||
73f576c0 | 5322 | mem_cgroup_id_put(memcg); |
df878fb0 KH |
5323 | } |
5324 | ||
6df38689 VD |
5325 | static void mem_cgroup_css_released(struct cgroup_subsys_state *css) |
5326 | { | |
5327 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5328 | ||
5329 | invalidate_reclaim_iterators(memcg); | |
5330 | } | |
5331 | ||
eb95419b | 5332 | static void mem_cgroup_css_free(struct cgroup_subsys_state *css) |
8cdea7c0 | 5333 | { |
eb95419b | 5334 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
97b27821 | 5335 | int __maybe_unused i; |
c268e994 | 5336 | |
97b27821 TH |
5337 | #ifdef CONFIG_CGROUP_WRITEBACK |
5338 | for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) | |
5339 | wb_wait_for_completion(&memcg->cgwb_frn[i].done); | |
5340 | #endif | |
f7e1cb6e | 5341 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 5342 | static_branch_dec(&memcg_sockets_enabled_key); |
127424c8 | 5343 | |
0db15298 | 5344 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_active) |
d55f90bf | 5345 | static_branch_dec(&memcg_sockets_enabled_key); |
3893e302 | 5346 | |
0b8f73e1 JW |
5347 | vmpressure_cleanup(&memcg->vmpressure); |
5348 | cancel_work_sync(&memcg->high_work); | |
5349 | mem_cgroup_remove_from_trees(memcg); | |
e4262c4f | 5350 | free_shrinker_info(memcg); |
0b8f73e1 | 5351 | mem_cgroup_free(memcg); |
8cdea7c0 BS |
5352 | } |
5353 | ||
1ced953b TH |
5354 | /** |
5355 | * mem_cgroup_css_reset - reset the states of a mem_cgroup | |
5356 | * @css: the target css | |
5357 | * | |
5358 | * Reset the states of the mem_cgroup associated with @css. This is | |
5359 | * invoked when the userland requests disabling on the default hierarchy | |
5360 | * but the memcg is pinned through dependency. The memcg should stop | |
5361 | * applying policies and should revert to the vanilla state as it may be | |
5362 | * made visible again. | |
5363 | * | |
5364 | * The current implementation only resets the essential configurations. | |
5365 | * This needs to be expanded to cover all the visible parts. | |
5366 | */ | |
5367 | static void mem_cgroup_css_reset(struct cgroup_subsys_state *css) | |
5368 | { | |
5369 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5370 | ||
bbec2e15 RG |
5371 | page_counter_set_max(&memcg->memory, PAGE_COUNTER_MAX); |
5372 | page_counter_set_max(&memcg->swap, PAGE_COUNTER_MAX); | |
bbec2e15 RG |
5373 | page_counter_set_max(&memcg->kmem, PAGE_COUNTER_MAX); |
5374 | page_counter_set_max(&memcg->tcpmem, PAGE_COUNTER_MAX); | |
bf8d5d52 | 5375 | page_counter_set_min(&memcg->memory, 0); |
23067153 | 5376 | page_counter_set_low(&memcg->memory, 0); |
d1663a90 | 5377 | page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX); |
24d404dc | 5378 | memcg->soft_limit = PAGE_COUNTER_MAX; |
4b82ab4f | 5379 | page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX); |
2529bb3a | 5380 | memcg_wb_domain_size_changed(memcg); |
1ced953b TH |
5381 | } |
5382 | ||
2d146aa3 JW |
5383 | static void mem_cgroup_css_rstat_flush(struct cgroup_subsys_state *css, int cpu) |
5384 | { | |
5385 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
5386 | struct mem_cgroup *parent = parent_mem_cgroup(memcg); | |
5387 | struct memcg_vmstats_percpu *statc; | |
5388 | long delta, v; | |
7e1c0d6f | 5389 | int i, nid; |
2d146aa3 JW |
5390 | |
5391 | statc = per_cpu_ptr(memcg->vmstats_percpu, cpu); | |
5392 | ||
5393 | for (i = 0; i < MEMCG_NR_STAT; i++) { | |
5394 | /* | |
5395 | * Collect the aggregated propagation counts of groups | |
5396 | * below us. We're in a per-cpu loop here and this is | |
5397 | * a global counter, so the first cycle will get them. | |
5398 | */ | |
5399 | delta = memcg->vmstats.state_pending[i]; | |
5400 | if (delta) | |
5401 | memcg->vmstats.state_pending[i] = 0; | |
5402 | ||
5403 | /* Add CPU changes on this level since the last flush */ | |
5404 | v = READ_ONCE(statc->state[i]); | |
5405 | if (v != statc->state_prev[i]) { | |
5406 | delta += v - statc->state_prev[i]; | |
5407 | statc->state_prev[i] = v; | |
5408 | } | |
5409 | ||
5410 | if (!delta) | |
5411 | continue; | |
5412 | ||
5413 | /* Aggregate counts on this level and propagate upwards */ | |
5414 | memcg->vmstats.state[i] += delta; | |
5415 | if (parent) | |
5416 | parent->vmstats.state_pending[i] += delta; | |
5417 | } | |
5418 | ||
5419 | for (i = 0; i < NR_VM_EVENT_ITEMS; i++) { | |
5420 | delta = memcg->vmstats.events_pending[i]; | |
5421 | if (delta) | |
5422 | memcg->vmstats.events_pending[i] = 0; | |
5423 | ||
5424 | v = READ_ONCE(statc->events[i]); | |
5425 | if (v != statc->events_prev[i]) { | |
5426 | delta += v - statc->events_prev[i]; | |
5427 | statc->events_prev[i] = v; | |
5428 | } | |
5429 | ||
5430 | if (!delta) | |
5431 | continue; | |
5432 | ||
5433 | memcg->vmstats.events[i] += delta; | |
5434 | if (parent) | |
5435 | parent->vmstats.events_pending[i] += delta; | |
5436 | } | |
7e1c0d6f SB |
5437 | |
5438 | for_each_node_state(nid, N_MEMORY) { | |
5439 | struct mem_cgroup_per_node *pn = memcg->nodeinfo[nid]; | |
5440 | struct mem_cgroup_per_node *ppn = NULL; | |
5441 | struct lruvec_stats_percpu *lstatc; | |
5442 | ||
5443 | if (parent) | |
5444 | ppn = parent->nodeinfo[nid]; | |
5445 | ||
5446 | lstatc = per_cpu_ptr(pn->lruvec_stats_percpu, cpu); | |
5447 | ||
5448 | for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { | |
5449 | delta = pn->lruvec_stats.state_pending[i]; | |
5450 | if (delta) | |
5451 | pn->lruvec_stats.state_pending[i] = 0; | |
5452 | ||
5453 | v = READ_ONCE(lstatc->state[i]); | |
5454 | if (v != lstatc->state_prev[i]) { | |
5455 | delta += v - lstatc->state_prev[i]; | |
5456 | lstatc->state_prev[i] = v; | |
5457 | } | |
5458 | ||
5459 | if (!delta) | |
5460 | continue; | |
5461 | ||
5462 | pn->lruvec_stats.state[i] += delta; | |
5463 | if (ppn) | |
5464 | ppn->lruvec_stats.state_pending[i] += delta; | |
5465 | } | |
5466 | } | |
2d146aa3 JW |
5467 | } |
5468 | ||
02491447 | 5469 | #ifdef CONFIG_MMU |
7dc74be0 | 5470 | /* Handlers for move charge at task migration. */ |
854ffa8d | 5471 | static int mem_cgroup_do_precharge(unsigned long count) |
7dc74be0 | 5472 | { |
05b84301 | 5473 | int ret; |
9476db97 | 5474 | |
d0164adc MG |
5475 | /* Try a single bulk charge without reclaim first, kswapd may wake */ |
5476 | ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_DIRECT_RECLAIM, count); | |
9476db97 | 5477 | if (!ret) { |
854ffa8d | 5478 | mc.precharge += count; |
854ffa8d DN |
5479 | return ret; |
5480 | } | |
9476db97 | 5481 | |
3674534b | 5482 | /* Try charges one by one with reclaim, but do not retry */ |
854ffa8d | 5483 | while (count--) { |
3674534b | 5484 | ret = try_charge(mc.to, GFP_KERNEL | __GFP_NORETRY, 1); |
38c5d72f | 5485 | if (ret) |
38c5d72f | 5486 | return ret; |
854ffa8d | 5487 | mc.precharge++; |
9476db97 | 5488 | cond_resched(); |
854ffa8d | 5489 | } |
9476db97 | 5490 | return 0; |
4ffef5fe DN |
5491 | } |
5492 | ||
4ffef5fe DN |
5493 | union mc_target { |
5494 | struct page *page; | |
02491447 | 5495 | swp_entry_t ent; |
4ffef5fe DN |
5496 | }; |
5497 | ||
4ffef5fe | 5498 | enum mc_target_type { |
8d32ff84 | 5499 | MC_TARGET_NONE = 0, |
4ffef5fe | 5500 | MC_TARGET_PAGE, |
02491447 | 5501 | MC_TARGET_SWAP, |
c733a828 | 5502 | MC_TARGET_DEVICE, |
4ffef5fe DN |
5503 | }; |
5504 | ||
90254a65 DN |
5505 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
5506 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 5507 | { |
25b2995a | 5508 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 5509 | |
90254a65 DN |
5510 | if (!page || !page_mapped(page)) |
5511 | return NULL; | |
5512 | if (PageAnon(page)) { | |
1dfab5ab | 5513 | if (!(mc.flags & MOVE_ANON)) |
90254a65 | 5514 | return NULL; |
1dfab5ab JW |
5515 | } else { |
5516 | if (!(mc.flags & MOVE_FILE)) | |
5517 | return NULL; | |
5518 | } | |
90254a65 DN |
5519 | if (!get_page_unless_zero(page)) |
5520 | return NULL; | |
5521 | ||
5522 | return page; | |
5523 | } | |
5524 | ||
c733a828 | 5525 | #if defined(CONFIG_SWAP) || defined(CONFIG_DEVICE_PRIVATE) |
90254a65 | 5526 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, |
48406ef8 | 5527 | pte_t ptent, swp_entry_t *entry) |
90254a65 | 5528 | { |
90254a65 DN |
5529 | struct page *page = NULL; |
5530 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
5531 | ||
9a137153 | 5532 | if (!(mc.flags & MOVE_ANON)) |
90254a65 | 5533 | return NULL; |
c733a828 JG |
5534 | |
5535 | /* | |
27674ef6 CH |
5536 | * Handle device private pages that are not accessible by the CPU, but |
5537 | * stored as special swap entries in the page table. | |
c733a828 JG |
5538 | */ |
5539 | if (is_device_private_entry(ent)) { | |
af5cdaf8 | 5540 | page = pfn_swap_entry_to_page(ent); |
27674ef6 | 5541 | if (!get_page_unless_zero(page)) |
c733a828 JG |
5542 | return NULL; |
5543 | return page; | |
5544 | } | |
5545 | ||
9a137153 RC |
5546 | if (non_swap_entry(ent)) |
5547 | return NULL; | |
5548 | ||
4b91355e KH |
5549 | /* |
5550 | * Because lookup_swap_cache() updates some statistics counter, | |
5551 | * we call find_get_page() with swapper_space directly. | |
5552 | */ | |
f6ab1f7f | 5553 | page = find_get_page(swap_address_space(ent), swp_offset(ent)); |
2d1c4980 | 5554 | entry->val = ent.val; |
90254a65 DN |
5555 | |
5556 | return page; | |
5557 | } | |
4b91355e KH |
5558 | #else |
5559 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
48406ef8 | 5560 | pte_t ptent, swp_entry_t *entry) |
4b91355e KH |
5561 | { |
5562 | return NULL; | |
5563 | } | |
5564 | #endif | |
90254a65 | 5565 | |
87946a72 | 5566 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
48384b0b | 5567 | unsigned long addr, pte_t ptent) |
87946a72 | 5568 | { |
87946a72 DN |
5569 | if (!vma->vm_file) /* anonymous vma */ |
5570 | return NULL; | |
1dfab5ab | 5571 | if (!(mc.flags & MOVE_FILE)) |
87946a72 DN |
5572 | return NULL; |
5573 | ||
87946a72 | 5574 | /* page is moved even if it's not RSS of this task(page-faulted). */ |
aa3b1895 | 5575 | /* shmem/tmpfs may report page out on swap: account for that too. */ |
f5df8635 MWO |
5576 | return find_get_incore_page(vma->vm_file->f_mapping, |
5577 | linear_page_index(vma, addr)); | |
87946a72 DN |
5578 | } |
5579 | ||
b1b0deab CG |
5580 | /** |
5581 | * mem_cgroup_move_account - move account of the page | |
5582 | * @page: the page | |
25843c2b | 5583 | * @compound: charge the page as compound or small page |
b1b0deab CG |
5584 | * @from: mem_cgroup which the page is moved from. |
5585 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
5586 | * | |
3ac808fd | 5587 | * The caller must make sure the page is not on LRU (isolate_page() is useful.) |
b1b0deab CG |
5588 | * |
5589 | * This function doesn't do "charge" to new cgroup and doesn't do "uncharge" | |
5590 | * from old cgroup. | |
5591 | */ | |
5592 | static int mem_cgroup_move_account(struct page *page, | |
f627c2f5 | 5593 | bool compound, |
b1b0deab CG |
5594 | struct mem_cgroup *from, |
5595 | struct mem_cgroup *to) | |
5596 | { | |
fcce4672 | 5597 | struct folio *folio = page_folio(page); |
ae8af438 KK |
5598 | struct lruvec *from_vec, *to_vec; |
5599 | struct pglist_data *pgdat; | |
fcce4672 | 5600 | unsigned int nr_pages = compound ? folio_nr_pages(folio) : 1; |
8e88bd2d | 5601 | int nid, ret; |
b1b0deab CG |
5602 | |
5603 | VM_BUG_ON(from == to); | |
fcce4672 | 5604 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
9c325215 | 5605 | VM_BUG_ON(compound && !folio_test_large(folio)); |
b1b0deab CG |
5606 | |
5607 | /* | |
6a93ca8f | 5608 | * Prevent mem_cgroup_migrate() from looking at |
bcfe06bf | 5609 | * page's memory cgroup of its source page while we change it. |
b1b0deab | 5610 | */ |
f627c2f5 | 5611 | ret = -EBUSY; |
fcce4672 | 5612 | if (!folio_trylock(folio)) |
b1b0deab CG |
5613 | goto out; |
5614 | ||
5615 | ret = -EINVAL; | |
fcce4672 | 5616 | if (folio_memcg(folio) != from) |
b1b0deab CG |
5617 | goto out_unlock; |
5618 | ||
fcce4672 | 5619 | pgdat = folio_pgdat(folio); |
867e5e1d JW |
5620 | from_vec = mem_cgroup_lruvec(from, pgdat); |
5621 | to_vec = mem_cgroup_lruvec(to, pgdat); | |
ae8af438 | 5622 | |
fcce4672 | 5623 | folio_memcg_lock(folio); |
b1b0deab | 5624 | |
fcce4672 MWO |
5625 | if (folio_test_anon(folio)) { |
5626 | if (folio_mapped(folio)) { | |
be5d0a74 JW |
5627 | __mod_lruvec_state(from_vec, NR_ANON_MAPPED, -nr_pages); |
5628 | __mod_lruvec_state(to_vec, NR_ANON_MAPPED, nr_pages); | |
fcce4672 | 5629 | if (folio_test_transhuge(folio)) { |
69473e5d MS |
5630 | __mod_lruvec_state(from_vec, NR_ANON_THPS, |
5631 | -nr_pages); | |
5632 | __mod_lruvec_state(to_vec, NR_ANON_THPS, | |
5633 | nr_pages); | |
468c3982 | 5634 | } |
be5d0a74 JW |
5635 | } |
5636 | } else { | |
0d1c2072 JW |
5637 | __mod_lruvec_state(from_vec, NR_FILE_PAGES, -nr_pages); |
5638 | __mod_lruvec_state(to_vec, NR_FILE_PAGES, nr_pages); | |
5639 | ||
fcce4672 | 5640 | if (folio_test_swapbacked(folio)) { |
0d1c2072 JW |
5641 | __mod_lruvec_state(from_vec, NR_SHMEM, -nr_pages); |
5642 | __mod_lruvec_state(to_vec, NR_SHMEM, nr_pages); | |
5643 | } | |
5644 | ||
fcce4672 | 5645 | if (folio_mapped(folio)) { |
49e50d27 JW |
5646 | __mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages); |
5647 | __mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages); | |
5648 | } | |
b1b0deab | 5649 | |
fcce4672 MWO |
5650 | if (folio_test_dirty(folio)) { |
5651 | struct address_space *mapping = folio_mapping(folio); | |
c4843a75 | 5652 | |
f56753ac | 5653 | if (mapping_can_writeback(mapping)) { |
49e50d27 JW |
5654 | __mod_lruvec_state(from_vec, NR_FILE_DIRTY, |
5655 | -nr_pages); | |
5656 | __mod_lruvec_state(to_vec, NR_FILE_DIRTY, | |
5657 | nr_pages); | |
5658 | } | |
c4843a75 GT |
5659 | } |
5660 | } | |
5661 | ||
fcce4672 | 5662 | if (folio_test_writeback(folio)) { |
ae8af438 KK |
5663 | __mod_lruvec_state(from_vec, NR_WRITEBACK, -nr_pages); |
5664 | __mod_lruvec_state(to_vec, NR_WRITEBACK, nr_pages); | |
b1b0deab CG |
5665 | } |
5666 | ||
5667 | /* | |
abb242f5 JW |
5668 | * All state has been migrated, let's switch to the new memcg. |
5669 | * | |
bcfe06bf | 5670 | * It is safe to change page's memcg here because the page |
abb242f5 JW |
5671 | * is referenced, charged, isolated, and locked: we can't race |
5672 | * with (un)charging, migration, LRU putback, or anything else | |
bcfe06bf | 5673 | * that would rely on a stable page's memory cgroup. |
abb242f5 JW |
5674 | * |
5675 | * Note that lock_page_memcg is a memcg lock, not a page lock, | |
bcfe06bf | 5676 | * to save space. As soon as we switch page's memory cgroup to a |
abb242f5 JW |
5677 | * new memcg that isn't locked, the above state can change |
5678 | * concurrently again. Make sure we're truly done with it. | |
b1b0deab | 5679 | */ |
abb242f5 | 5680 | smp_mb(); |
b1b0deab | 5681 | |
1a3e1f40 JW |
5682 | css_get(&to->css); |
5683 | css_put(&from->css); | |
5684 | ||
fcce4672 | 5685 | folio->memcg_data = (unsigned long)to; |
87eaceb3 | 5686 | |
f70ad448 | 5687 | __folio_memcg_unlock(from); |
b1b0deab CG |
5688 | |
5689 | ret = 0; | |
fcce4672 | 5690 | nid = folio_nid(folio); |
b1b0deab CG |
5691 | |
5692 | local_irq_disable(); | |
6e0110c2 | 5693 | mem_cgroup_charge_statistics(to, nr_pages); |
8e88bd2d | 5694 | memcg_check_events(to, nid); |
6e0110c2 | 5695 | mem_cgroup_charge_statistics(from, -nr_pages); |
8e88bd2d | 5696 | memcg_check_events(from, nid); |
b1b0deab CG |
5697 | local_irq_enable(); |
5698 | out_unlock: | |
fcce4672 | 5699 | folio_unlock(folio); |
b1b0deab CG |
5700 | out: |
5701 | return ret; | |
5702 | } | |
5703 | ||
7cf7806c LR |
5704 | /** |
5705 | * get_mctgt_type - get target type of moving charge | |
5706 | * @vma: the vma the pte to be checked belongs | |
5707 | * @addr: the address corresponding to the pte to be checked | |
5708 | * @ptent: the pte to be checked | |
5709 | * @target: the pointer the target page or swap ent will be stored(can be NULL) | |
5710 | * | |
5711 | * Returns | |
5712 | * 0(MC_TARGET_NONE): if the pte is not a target for move charge. | |
5713 | * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for | |
5714 | * move charge. if @target is not NULL, the page is stored in target->page | |
5715 | * with extra refcnt got(Callers should handle it). | |
5716 | * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a | |
5717 | * target for charge migration. if @target is not NULL, the entry is stored | |
5718 | * in target->ent. | |
f25cbb7a AS |
5719 | * 3(MC_TARGET_DEVICE): like MC_TARGET_PAGE but page is device memory and |
5720 | * thus not on the lru. | |
df6ad698 JG |
5721 | * For now we such page is charge like a regular page would be as for all |
5722 | * intent and purposes it is just special memory taking the place of a | |
5723 | * regular page. | |
c733a828 JG |
5724 | * |
5725 | * See Documentations/vm/hmm.txt and include/linux/hmm.h | |
7cf7806c LR |
5726 | * |
5727 | * Called with pte lock held. | |
5728 | */ | |
5729 | ||
8d32ff84 | 5730 | static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, |
90254a65 DN |
5731 | unsigned long addr, pte_t ptent, union mc_target *target) |
5732 | { | |
5733 | struct page *page = NULL; | |
8d32ff84 | 5734 | enum mc_target_type ret = MC_TARGET_NONE; |
90254a65 DN |
5735 | swp_entry_t ent = { .val = 0 }; |
5736 | ||
5737 | if (pte_present(ptent)) | |
5738 | page = mc_handle_present_pte(vma, addr, ptent); | |
5c041f5d PX |
5739 | else if (pte_none_mostly(ptent)) |
5740 | /* | |
5741 | * PTE markers should be treated as a none pte here, separated | |
5742 | * from other swap handling below. | |
5743 | */ | |
5744 | page = mc_handle_file_pte(vma, addr, ptent); | |
90254a65 | 5745 | else if (is_swap_pte(ptent)) |
48406ef8 | 5746 | page = mc_handle_swap_pte(vma, ptent, &ent); |
90254a65 DN |
5747 | |
5748 | if (!page && !ent.val) | |
8d32ff84 | 5749 | return ret; |
02491447 | 5750 | if (page) { |
02491447 | 5751 | /* |
0a31bc97 | 5752 | * Do only loose check w/o serialization. |
1306a85a | 5753 | * mem_cgroup_move_account() checks the page is valid or |
0a31bc97 | 5754 | * not under LRU exclusion. |
02491447 | 5755 | */ |
bcfe06bf | 5756 | if (page_memcg(page) == mc.from) { |
02491447 | 5757 | ret = MC_TARGET_PAGE; |
f25cbb7a AS |
5758 | if (is_device_private_page(page) || |
5759 | is_device_coherent_page(page)) | |
c733a828 | 5760 | ret = MC_TARGET_DEVICE; |
02491447 DN |
5761 | if (target) |
5762 | target->page = page; | |
5763 | } | |
5764 | if (!ret || !target) | |
5765 | put_page(page); | |
5766 | } | |
3e14a57b HY |
5767 | /* |
5768 | * There is a swap entry and a page doesn't exist or isn't charged. | |
5769 | * But we cannot move a tail-page in a THP. | |
5770 | */ | |
5771 | if (ent.val && !ret && (!page || !PageTransCompound(page)) && | |
34c00c31 | 5772 | mem_cgroup_id(mc.from) == lookup_swap_cgroup_id(ent)) { |
7f0f1546 KH |
5773 | ret = MC_TARGET_SWAP; |
5774 | if (target) | |
5775 | target->ent = ent; | |
4ffef5fe | 5776 | } |
4ffef5fe DN |
5777 | return ret; |
5778 | } | |
5779 | ||
12724850 NH |
5780 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
5781 | /* | |
d6810d73 HY |
5782 | * We don't consider PMD mapped swapping or file mapped pages because THP does |
5783 | * not support them for now. | |
12724850 NH |
5784 | * Caller should make sure that pmd_trans_huge(pmd) is true. |
5785 | */ | |
5786 | static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
5787 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
5788 | { | |
5789 | struct page *page = NULL; | |
12724850 NH |
5790 | enum mc_target_type ret = MC_TARGET_NONE; |
5791 | ||
84c3fc4e ZY |
5792 | if (unlikely(is_swap_pmd(pmd))) { |
5793 | VM_BUG_ON(thp_migration_supported() && | |
5794 | !is_pmd_migration_entry(pmd)); | |
5795 | return ret; | |
5796 | } | |
12724850 | 5797 | page = pmd_page(pmd); |
309381fe | 5798 | VM_BUG_ON_PAGE(!page || !PageHead(page), page); |
1dfab5ab | 5799 | if (!(mc.flags & MOVE_ANON)) |
12724850 | 5800 | return ret; |
bcfe06bf | 5801 | if (page_memcg(page) == mc.from) { |
12724850 NH |
5802 | ret = MC_TARGET_PAGE; |
5803 | if (target) { | |
5804 | get_page(page); | |
5805 | target->page = page; | |
5806 | } | |
5807 | } | |
5808 | return ret; | |
5809 | } | |
5810 | #else | |
5811 | static inline enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
5812 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
5813 | { | |
5814 | return MC_TARGET_NONE; | |
5815 | } | |
5816 | #endif | |
5817 | ||
4ffef5fe DN |
5818 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, |
5819 | unsigned long addr, unsigned long end, | |
5820 | struct mm_walk *walk) | |
5821 | { | |
26bcd64a | 5822 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
5823 | pte_t *pte; |
5824 | spinlock_t *ptl; | |
5825 | ||
b6ec57f4 KS |
5826 | ptl = pmd_trans_huge_lock(pmd, vma); |
5827 | if (ptl) { | |
c733a828 JG |
5828 | /* |
5829 | * Note their can not be MC_TARGET_DEVICE for now as we do not | |
25b2995a CH |
5830 | * support transparent huge page with MEMORY_DEVICE_PRIVATE but |
5831 | * this might change. | |
c733a828 | 5832 | */ |
12724850 NH |
5833 | if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE) |
5834 | mc.precharge += HPAGE_PMD_NR; | |
bf929152 | 5835 | spin_unlock(ptl); |
1a5a9906 | 5836 | return 0; |
12724850 | 5837 | } |
03319327 | 5838 | |
45f83cef AA |
5839 | if (pmd_trans_unstable(pmd)) |
5840 | return 0; | |
4ffef5fe DN |
5841 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
5842 | for (; addr != end; pte++, addr += PAGE_SIZE) | |
8d32ff84 | 5843 | if (get_mctgt_type(vma, addr, *pte, NULL)) |
4ffef5fe DN |
5844 | mc.precharge++; /* increment precharge temporarily */ |
5845 | pte_unmap_unlock(pte - 1, ptl); | |
5846 | cond_resched(); | |
5847 | ||
7dc74be0 DN |
5848 | return 0; |
5849 | } | |
5850 | ||
7b86ac33 CH |
5851 | static const struct mm_walk_ops precharge_walk_ops = { |
5852 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
5853 | }; | |
5854 | ||
4ffef5fe DN |
5855 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
5856 | { | |
5857 | unsigned long precharge; | |
4ffef5fe | 5858 | |
d8ed45c5 | 5859 | mmap_read_lock(mm); |
7b86ac33 | 5860 | walk_page_range(mm, 0, mm->highest_vm_end, &precharge_walk_ops, NULL); |
d8ed45c5 | 5861 | mmap_read_unlock(mm); |
4ffef5fe DN |
5862 | |
5863 | precharge = mc.precharge; | |
5864 | mc.precharge = 0; | |
5865 | ||
5866 | return precharge; | |
5867 | } | |
5868 | ||
4ffef5fe DN |
5869 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
5870 | { | |
dfe076b0 DN |
5871 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
5872 | ||
5873 | VM_BUG_ON(mc.moving_task); | |
5874 | mc.moving_task = current; | |
5875 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
5876 | } |
5877 | ||
dfe076b0 DN |
5878 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
5879 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 5880 | { |
2bd9bb20 KH |
5881 | struct mem_cgroup *from = mc.from; |
5882 | struct mem_cgroup *to = mc.to; | |
5883 | ||
4ffef5fe | 5884 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d | 5885 | if (mc.precharge) { |
00501b53 | 5886 | cancel_charge(mc.to, mc.precharge); |
854ffa8d DN |
5887 | mc.precharge = 0; |
5888 | } | |
5889 | /* | |
5890 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
5891 | * we must uncharge here. | |
5892 | */ | |
5893 | if (mc.moved_charge) { | |
00501b53 | 5894 | cancel_charge(mc.from, mc.moved_charge); |
854ffa8d | 5895 | mc.moved_charge = 0; |
4ffef5fe | 5896 | } |
483c30b5 DN |
5897 | /* we must fixup refcnts and charges */ |
5898 | if (mc.moved_swap) { | |
483c30b5 | 5899 | /* uncharge swap account from the old cgroup */ |
ce00a967 | 5900 | if (!mem_cgroup_is_root(mc.from)) |
3e32cb2e | 5901 | page_counter_uncharge(&mc.from->memsw, mc.moved_swap); |
483c30b5 | 5902 | |
615d66c3 VD |
5903 | mem_cgroup_id_put_many(mc.from, mc.moved_swap); |
5904 | ||
05b84301 | 5905 | /* |
3e32cb2e JW |
5906 | * we charged both to->memory and to->memsw, so we |
5907 | * should uncharge to->memory. | |
05b84301 | 5908 | */ |
ce00a967 | 5909 | if (!mem_cgroup_is_root(mc.to)) |
3e32cb2e JW |
5910 | page_counter_uncharge(&mc.to->memory, mc.moved_swap); |
5911 | ||
483c30b5 DN |
5912 | mc.moved_swap = 0; |
5913 | } | |
dfe076b0 DN |
5914 | memcg_oom_recover(from); |
5915 | memcg_oom_recover(to); | |
5916 | wake_up_all(&mc.waitq); | |
5917 | } | |
5918 | ||
5919 | static void mem_cgroup_clear_mc(void) | |
5920 | { | |
264a0ae1 TH |
5921 | struct mm_struct *mm = mc.mm; |
5922 | ||
dfe076b0 DN |
5923 | /* |
5924 | * we must clear moving_task before waking up waiters at the end of | |
5925 | * task migration. | |
5926 | */ | |
5927 | mc.moving_task = NULL; | |
5928 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 5929 | spin_lock(&mc.lock); |
4ffef5fe DN |
5930 | mc.from = NULL; |
5931 | mc.to = NULL; | |
264a0ae1 | 5932 | mc.mm = NULL; |
2bd9bb20 | 5933 | spin_unlock(&mc.lock); |
264a0ae1 TH |
5934 | |
5935 | mmput(mm); | |
4ffef5fe DN |
5936 | } |
5937 | ||
1f7dd3e5 | 5938 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
7dc74be0 | 5939 | { |
1f7dd3e5 | 5940 | struct cgroup_subsys_state *css; |
eed67d75 | 5941 | struct mem_cgroup *memcg = NULL; /* unneeded init to make gcc happy */ |
9f2115f9 | 5942 | struct mem_cgroup *from; |
4530eddb | 5943 | struct task_struct *leader, *p; |
9f2115f9 | 5944 | struct mm_struct *mm; |
1dfab5ab | 5945 | unsigned long move_flags; |
9f2115f9 | 5946 | int ret = 0; |
7dc74be0 | 5947 | |
1f7dd3e5 TH |
5948 | /* charge immigration isn't supported on the default hierarchy */ |
5949 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
9f2115f9 TH |
5950 | return 0; |
5951 | ||
4530eddb TH |
5952 | /* |
5953 | * Multi-process migrations only happen on the default hierarchy | |
5954 | * where charge immigration is not used. Perform charge | |
5955 | * immigration if @tset contains a leader and whine if there are | |
5956 | * multiple. | |
5957 | */ | |
5958 | p = NULL; | |
1f7dd3e5 | 5959 | cgroup_taskset_for_each_leader(leader, css, tset) { |
4530eddb TH |
5960 | WARN_ON_ONCE(p); |
5961 | p = leader; | |
1f7dd3e5 | 5962 | memcg = mem_cgroup_from_css(css); |
4530eddb TH |
5963 | } |
5964 | if (!p) | |
5965 | return 0; | |
5966 | ||
1f7dd3e5 | 5967 | /* |
f0953a1b | 5968 | * We are now committed to this value whatever it is. Changes in this |
1f7dd3e5 TH |
5969 | * tunable will only affect upcoming migrations, not the current one. |
5970 | * So we need to save it, and keep it going. | |
5971 | */ | |
5972 | move_flags = READ_ONCE(memcg->move_charge_at_immigrate); | |
5973 | if (!move_flags) | |
5974 | return 0; | |
5975 | ||
9f2115f9 TH |
5976 | from = mem_cgroup_from_task(p); |
5977 | ||
5978 | VM_BUG_ON(from == memcg); | |
5979 | ||
5980 | mm = get_task_mm(p); | |
5981 | if (!mm) | |
5982 | return 0; | |
5983 | /* We move charges only when we move a owner of the mm */ | |
5984 | if (mm->owner == p) { | |
5985 | VM_BUG_ON(mc.from); | |
5986 | VM_BUG_ON(mc.to); | |
5987 | VM_BUG_ON(mc.precharge); | |
5988 | VM_BUG_ON(mc.moved_charge); | |
5989 | VM_BUG_ON(mc.moved_swap); | |
5990 | ||
5991 | spin_lock(&mc.lock); | |
264a0ae1 | 5992 | mc.mm = mm; |
9f2115f9 TH |
5993 | mc.from = from; |
5994 | mc.to = memcg; | |
5995 | mc.flags = move_flags; | |
5996 | spin_unlock(&mc.lock); | |
5997 | /* We set mc.moving_task later */ | |
5998 | ||
5999 | ret = mem_cgroup_precharge_mc(mm); | |
6000 | if (ret) | |
6001 | mem_cgroup_clear_mc(); | |
264a0ae1 TH |
6002 | } else { |
6003 | mmput(mm); | |
7dc74be0 DN |
6004 | } |
6005 | return ret; | |
6006 | } | |
6007 | ||
1f7dd3e5 | 6008 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
7dc74be0 | 6009 | { |
4e2f245d JW |
6010 | if (mc.to) |
6011 | mem_cgroup_clear_mc(); | |
7dc74be0 DN |
6012 | } |
6013 | ||
4ffef5fe DN |
6014 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
6015 | unsigned long addr, unsigned long end, | |
6016 | struct mm_walk *walk) | |
7dc74be0 | 6017 | { |
4ffef5fe | 6018 | int ret = 0; |
26bcd64a | 6019 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
6020 | pte_t *pte; |
6021 | spinlock_t *ptl; | |
12724850 NH |
6022 | enum mc_target_type target_type; |
6023 | union mc_target target; | |
6024 | struct page *page; | |
4ffef5fe | 6025 | |
b6ec57f4 KS |
6026 | ptl = pmd_trans_huge_lock(pmd, vma); |
6027 | if (ptl) { | |
62ade86a | 6028 | if (mc.precharge < HPAGE_PMD_NR) { |
bf929152 | 6029 | spin_unlock(ptl); |
12724850 NH |
6030 | return 0; |
6031 | } | |
6032 | target_type = get_mctgt_type_thp(vma, addr, *pmd, &target); | |
6033 | if (target_type == MC_TARGET_PAGE) { | |
6034 | page = target.page; | |
6035 | if (!isolate_lru_page(page)) { | |
f627c2f5 | 6036 | if (!mem_cgroup_move_account(page, true, |
1306a85a | 6037 | mc.from, mc.to)) { |
12724850 NH |
6038 | mc.precharge -= HPAGE_PMD_NR; |
6039 | mc.moved_charge += HPAGE_PMD_NR; | |
6040 | } | |
6041 | putback_lru_page(page); | |
6042 | } | |
6043 | put_page(page); | |
c733a828 JG |
6044 | } else if (target_type == MC_TARGET_DEVICE) { |
6045 | page = target.page; | |
6046 | if (!mem_cgroup_move_account(page, true, | |
6047 | mc.from, mc.to)) { | |
6048 | mc.precharge -= HPAGE_PMD_NR; | |
6049 | mc.moved_charge += HPAGE_PMD_NR; | |
6050 | } | |
6051 | put_page(page); | |
12724850 | 6052 | } |
bf929152 | 6053 | spin_unlock(ptl); |
1a5a9906 | 6054 | return 0; |
12724850 NH |
6055 | } |
6056 | ||
45f83cef AA |
6057 | if (pmd_trans_unstable(pmd)) |
6058 | return 0; | |
4ffef5fe DN |
6059 | retry: |
6060 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
6061 | for (; addr != end; addr += PAGE_SIZE) { | |
6062 | pte_t ptent = *(pte++); | |
c733a828 | 6063 | bool device = false; |
02491447 | 6064 | swp_entry_t ent; |
4ffef5fe DN |
6065 | |
6066 | if (!mc.precharge) | |
6067 | break; | |
6068 | ||
8d32ff84 | 6069 | switch (get_mctgt_type(vma, addr, ptent, &target)) { |
c733a828 JG |
6070 | case MC_TARGET_DEVICE: |
6071 | device = true; | |
e4a9bc58 | 6072 | fallthrough; |
4ffef5fe DN |
6073 | case MC_TARGET_PAGE: |
6074 | page = target.page; | |
53f9263b KS |
6075 | /* |
6076 | * We can have a part of the split pmd here. Moving it | |
6077 | * can be done but it would be too convoluted so simply | |
6078 | * ignore such a partial THP and keep it in original | |
6079 | * memcg. There should be somebody mapping the head. | |
6080 | */ | |
6081 | if (PageTransCompound(page)) | |
6082 | goto put; | |
c733a828 | 6083 | if (!device && isolate_lru_page(page)) |
4ffef5fe | 6084 | goto put; |
f627c2f5 KS |
6085 | if (!mem_cgroup_move_account(page, false, |
6086 | mc.from, mc.to)) { | |
4ffef5fe | 6087 | mc.precharge--; |
854ffa8d DN |
6088 | /* we uncharge from mc.from later. */ |
6089 | mc.moved_charge++; | |
4ffef5fe | 6090 | } |
c733a828 JG |
6091 | if (!device) |
6092 | putback_lru_page(page); | |
8d32ff84 | 6093 | put: /* get_mctgt_type() gets the page */ |
4ffef5fe DN |
6094 | put_page(page); |
6095 | break; | |
02491447 DN |
6096 | case MC_TARGET_SWAP: |
6097 | ent = target.ent; | |
e91cbb42 | 6098 | if (!mem_cgroup_move_swap_account(ent, mc.from, mc.to)) { |
02491447 | 6099 | mc.precharge--; |
8d22a935 HD |
6100 | mem_cgroup_id_get_many(mc.to, 1); |
6101 | /* we fixup other refcnts and charges later. */ | |
483c30b5 DN |
6102 | mc.moved_swap++; |
6103 | } | |
02491447 | 6104 | break; |
4ffef5fe DN |
6105 | default: |
6106 | break; | |
6107 | } | |
6108 | } | |
6109 | pte_unmap_unlock(pte - 1, ptl); | |
6110 | cond_resched(); | |
6111 | ||
6112 | if (addr != end) { | |
6113 | /* | |
6114 | * We have consumed all precharges we got in can_attach(). | |
6115 | * We try charge one by one, but don't do any additional | |
6116 | * charges to mc.to if we have failed in charge once in attach() | |
6117 | * phase. | |
6118 | */ | |
854ffa8d | 6119 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
6120 | if (!ret) |
6121 | goto retry; | |
6122 | } | |
6123 | ||
6124 | return ret; | |
6125 | } | |
6126 | ||
7b86ac33 CH |
6127 | static const struct mm_walk_ops charge_walk_ops = { |
6128 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
6129 | }; | |
6130 | ||
264a0ae1 | 6131 | static void mem_cgroup_move_charge(void) |
4ffef5fe | 6132 | { |
4ffef5fe | 6133 | lru_add_drain_all(); |
312722cb | 6134 | /* |
81f8c3a4 JW |
6135 | * Signal lock_page_memcg() to take the memcg's move_lock |
6136 | * while we're moving its pages to another memcg. Then wait | |
6137 | * for already started RCU-only updates to finish. | |
312722cb JW |
6138 | */ |
6139 | atomic_inc(&mc.from->moving_account); | |
6140 | synchronize_rcu(); | |
dfe076b0 | 6141 | retry: |
d8ed45c5 | 6142 | if (unlikely(!mmap_read_trylock(mc.mm))) { |
dfe076b0 | 6143 | /* |
c1e8d7c6 | 6144 | * Someone who are holding the mmap_lock might be waiting in |
dfe076b0 DN |
6145 | * waitq. So we cancel all extra charges, wake up all waiters, |
6146 | * and retry. Because we cancel precharges, we might not be able | |
6147 | * to move enough charges, but moving charge is a best-effort | |
6148 | * feature anyway, so it wouldn't be a big problem. | |
6149 | */ | |
6150 | __mem_cgroup_clear_mc(); | |
6151 | cond_resched(); | |
6152 | goto retry; | |
6153 | } | |
26bcd64a NH |
6154 | /* |
6155 | * When we have consumed all precharges and failed in doing | |
6156 | * additional charge, the page walk just aborts. | |
6157 | */ | |
7b86ac33 CH |
6158 | walk_page_range(mc.mm, 0, mc.mm->highest_vm_end, &charge_walk_ops, |
6159 | NULL); | |
0247f3f4 | 6160 | |
d8ed45c5 | 6161 | mmap_read_unlock(mc.mm); |
312722cb | 6162 | atomic_dec(&mc.from->moving_account); |
7dc74be0 DN |
6163 | } |
6164 | ||
264a0ae1 | 6165 | static void mem_cgroup_move_task(void) |
67e465a7 | 6166 | { |
264a0ae1 TH |
6167 | if (mc.to) { |
6168 | mem_cgroup_move_charge(); | |
a433658c | 6169 | mem_cgroup_clear_mc(); |
264a0ae1 | 6170 | } |
67e465a7 | 6171 | } |
5cfb80a7 | 6172 | #else /* !CONFIG_MMU */ |
1f7dd3e5 | 6173 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
6174 | { |
6175 | return 0; | |
6176 | } | |
1f7dd3e5 | 6177 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
6178 | { |
6179 | } | |
264a0ae1 | 6180 | static void mem_cgroup_move_task(void) |
5cfb80a7 DN |
6181 | { |
6182 | } | |
6183 | #endif | |
67e465a7 | 6184 | |
677dc973 CD |
6185 | static int seq_puts_memcg_tunable(struct seq_file *m, unsigned long value) |
6186 | { | |
6187 | if (value == PAGE_COUNTER_MAX) | |
6188 | seq_puts(m, "max\n"); | |
6189 | else | |
6190 | seq_printf(m, "%llu\n", (u64)value * PAGE_SIZE); | |
6191 | ||
6192 | return 0; | |
6193 | } | |
6194 | ||
241994ed JW |
6195 | static u64 memory_current_read(struct cgroup_subsys_state *css, |
6196 | struct cftype *cft) | |
6197 | { | |
f5fc3c5d JW |
6198 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
6199 | ||
6200 | return (u64)page_counter_read(&memcg->memory) * PAGE_SIZE; | |
241994ed JW |
6201 | } |
6202 | ||
8e20d4b3 GR |
6203 | static u64 memory_peak_read(struct cgroup_subsys_state *css, |
6204 | struct cftype *cft) | |
6205 | { | |
6206 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
6207 | ||
6208 | return (u64)memcg->memory.watermark * PAGE_SIZE; | |
6209 | } | |
6210 | ||
bf8d5d52 RG |
6211 | static int memory_min_show(struct seq_file *m, void *v) |
6212 | { | |
677dc973 CD |
6213 | return seq_puts_memcg_tunable(m, |
6214 | READ_ONCE(mem_cgroup_from_seq(m)->memory.min)); | |
bf8d5d52 RG |
6215 | } |
6216 | ||
6217 | static ssize_t memory_min_write(struct kernfs_open_file *of, | |
6218 | char *buf, size_t nbytes, loff_t off) | |
6219 | { | |
6220 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6221 | unsigned long min; | |
6222 | int err; | |
6223 | ||
6224 | buf = strstrip(buf); | |
6225 | err = page_counter_memparse(buf, "max", &min); | |
6226 | if (err) | |
6227 | return err; | |
6228 | ||
6229 | page_counter_set_min(&memcg->memory, min); | |
6230 | ||
6231 | return nbytes; | |
6232 | } | |
6233 | ||
241994ed JW |
6234 | static int memory_low_show(struct seq_file *m, void *v) |
6235 | { | |
677dc973 CD |
6236 | return seq_puts_memcg_tunable(m, |
6237 | READ_ONCE(mem_cgroup_from_seq(m)->memory.low)); | |
241994ed JW |
6238 | } |
6239 | ||
6240 | static ssize_t memory_low_write(struct kernfs_open_file *of, | |
6241 | char *buf, size_t nbytes, loff_t off) | |
6242 | { | |
6243 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6244 | unsigned long low; | |
6245 | int err; | |
6246 | ||
6247 | buf = strstrip(buf); | |
d2973697 | 6248 | err = page_counter_memparse(buf, "max", &low); |
241994ed JW |
6249 | if (err) |
6250 | return err; | |
6251 | ||
23067153 | 6252 | page_counter_set_low(&memcg->memory, low); |
241994ed JW |
6253 | |
6254 | return nbytes; | |
6255 | } | |
6256 | ||
6257 | static int memory_high_show(struct seq_file *m, void *v) | |
6258 | { | |
d1663a90 JK |
6259 | return seq_puts_memcg_tunable(m, |
6260 | READ_ONCE(mem_cgroup_from_seq(m)->memory.high)); | |
241994ed JW |
6261 | } |
6262 | ||
6263 | static ssize_t memory_high_write(struct kernfs_open_file *of, | |
6264 | char *buf, size_t nbytes, loff_t off) | |
6265 | { | |
6266 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
d977aa93 | 6267 | unsigned int nr_retries = MAX_RECLAIM_RETRIES; |
8c8c383c | 6268 | bool drained = false; |
241994ed JW |
6269 | unsigned long high; |
6270 | int err; | |
6271 | ||
6272 | buf = strstrip(buf); | |
d2973697 | 6273 | err = page_counter_memparse(buf, "max", &high); |
241994ed JW |
6274 | if (err) |
6275 | return err; | |
6276 | ||
e82553c1 JW |
6277 | page_counter_set_high(&memcg->memory, high); |
6278 | ||
8c8c383c JW |
6279 | for (;;) { |
6280 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
6281 | unsigned long reclaimed; | |
6282 | ||
6283 | if (nr_pages <= high) | |
6284 | break; | |
6285 | ||
6286 | if (signal_pending(current)) | |
6287 | break; | |
6288 | ||
6289 | if (!drained) { | |
6290 | drain_all_stock(memcg); | |
6291 | drained = true; | |
6292 | continue; | |
6293 | } | |
6294 | ||
6295 | reclaimed = try_to_free_mem_cgroup_pages(memcg, nr_pages - high, | |
6296 | GFP_KERNEL, true); | |
6297 | ||
6298 | if (!reclaimed && !nr_retries--) | |
6299 | break; | |
6300 | } | |
588083bb | 6301 | |
19ce33ac | 6302 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
6303 | return nbytes; |
6304 | } | |
6305 | ||
6306 | static int memory_max_show(struct seq_file *m, void *v) | |
6307 | { | |
677dc973 CD |
6308 | return seq_puts_memcg_tunable(m, |
6309 | READ_ONCE(mem_cgroup_from_seq(m)->memory.max)); | |
241994ed JW |
6310 | } |
6311 | ||
6312 | static ssize_t memory_max_write(struct kernfs_open_file *of, | |
6313 | char *buf, size_t nbytes, loff_t off) | |
6314 | { | |
6315 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
d977aa93 | 6316 | unsigned int nr_reclaims = MAX_RECLAIM_RETRIES; |
b6e6edcf | 6317 | bool drained = false; |
241994ed JW |
6318 | unsigned long max; |
6319 | int err; | |
6320 | ||
6321 | buf = strstrip(buf); | |
d2973697 | 6322 | err = page_counter_memparse(buf, "max", &max); |
241994ed JW |
6323 | if (err) |
6324 | return err; | |
6325 | ||
bbec2e15 | 6326 | xchg(&memcg->memory.max, max); |
b6e6edcf JW |
6327 | |
6328 | for (;;) { | |
6329 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
6330 | ||
6331 | if (nr_pages <= max) | |
6332 | break; | |
6333 | ||
7249c9f0 | 6334 | if (signal_pending(current)) |
b6e6edcf | 6335 | break; |
b6e6edcf JW |
6336 | |
6337 | if (!drained) { | |
6338 | drain_all_stock(memcg); | |
6339 | drained = true; | |
6340 | continue; | |
6341 | } | |
6342 | ||
6343 | if (nr_reclaims) { | |
6344 | if (!try_to_free_mem_cgroup_pages(memcg, nr_pages - max, | |
6345 | GFP_KERNEL, true)) | |
6346 | nr_reclaims--; | |
6347 | continue; | |
6348 | } | |
6349 | ||
e27be240 | 6350 | memcg_memory_event(memcg, MEMCG_OOM); |
b6e6edcf JW |
6351 | if (!mem_cgroup_out_of_memory(memcg, GFP_KERNEL, 0)) |
6352 | break; | |
6353 | } | |
241994ed | 6354 | |
2529bb3a | 6355 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
6356 | return nbytes; |
6357 | } | |
6358 | ||
1e577f97 SB |
6359 | static void __memory_events_show(struct seq_file *m, atomic_long_t *events) |
6360 | { | |
6361 | seq_printf(m, "low %lu\n", atomic_long_read(&events[MEMCG_LOW])); | |
6362 | seq_printf(m, "high %lu\n", atomic_long_read(&events[MEMCG_HIGH])); | |
6363 | seq_printf(m, "max %lu\n", atomic_long_read(&events[MEMCG_MAX])); | |
6364 | seq_printf(m, "oom %lu\n", atomic_long_read(&events[MEMCG_OOM])); | |
6365 | seq_printf(m, "oom_kill %lu\n", | |
6366 | atomic_long_read(&events[MEMCG_OOM_KILL])); | |
b6bf9abb DS |
6367 | seq_printf(m, "oom_group_kill %lu\n", |
6368 | atomic_long_read(&events[MEMCG_OOM_GROUP_KILL])); | |
1e577f97 SB |
6369 | } |
6370 | ||
241994ed JW |
6371 | static int memory_events_show(struct seq_file *m, void *v) |
6372 | { | |
aa9694bb | 6373 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
241994ed | 6374 | |
1e577f97 SB |
6375 | __memory_events_show(m, memcg->memory_events); |
6376 | return 0; | |
6377 | } | |
6378 | ||
6379 | static int memory_events_local_show(struct seq_file *m, void *v) | |
6380 | { | |
6381 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); | |
241994ed | 6382 | |
1e577f97 | 6383 | __memory_events_show(m, memcg->memory_events_local); |
241994ed JW |
6384 | return 0; |
6385 | } | |
6386 | ||
587d9f72 JW |
6387 | static int memory_stat_show(struct seq_file *m, void *v) |
6388 | { | |
aa9694bb | 6389 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
c8713d0b | 6390 | char *buf; |
1ff9e6e1 | 6391 | |
c8713d0b JW |
6392 | buf = memory_stat_format(memcg); |
6393 | if (!buf) | |
6394 | return -ENOMEM; | |
6395 | seq_puts(m, buf); | |
6396 | kfree(buf); | |
587d9f72 JW |
6397 | return 0; |
6398 | } | |
6399 | ||
5f9a4f4a | 6400 | #ifdef CONFIG_NUMA |
fff66b79 MS |
6401 | static inline unsigned long lruvec_page_state_output(struct lruvec *lruvec, |
6402 | int item) | |
6403 | { | |
6404 | return lruvec_page_state(lruvec, item) * memcg_page_state_unit(item); | |
6405 | } | |
6406 | ||
5f9a4f4a MS |
6407 | static int memory_numa_stat_show(struct seq_file *m, void *v) |
6408 | { | |
6409 | int i; | |
6410 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); | |
6411 | ||
fd25a9e0 | 6412 | mem_cgroup_flush_stats(); |
7e1c0d6f | 6413 | |
5f9a4f4a MS |
6414 | for (i = 0; i < ARRAY_SIZE(memory_stats); i++) { |
6415 | int nid; | |
6416 | ||
6417 | if (memory_stats[i].idx >= NR_VM_NODE_STAT_ITEMS) | |
6418 | continue; | |
6419 | ||
6420 | seq_printf(m, "%s", memory_stats[i].name); | |
6421 | for_each_node_state(nid, N_MEMORY) { | |
6422 | u64 size; | |
6423 | struct lruvec *lruvec; | |
6424 | ||
6425 | lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); | |
fff66b79 MS |
6426 | size = lruvec_page_state_output(lruvec, |
6427 | memory_stats[i].idx); | |
5f9a4f4a MS |
6428 | seq_printf(m, " N%d=%llu", nid, size); |
6429 | } | |
6430 | seq_putc(m, '\n'); | |
6431 | } | |
6432 | ||
6433 | return 0; | |
6434 | } | |
6435 | #endif | |
6436 | ||
3d8b38eb RG |
6437 | static int memory_oom_group_show(struct seq_file *m, void *v) |
6438 | { | |
aa9694bb | 6439 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
3d8b38eb RG |
6440 | |
6441 | seq_printf(m, "%d\n", memcg->oom_group); | |
6442 | ||
6443 | return 0; | |
6444 | } | |
6445 | ||
6446 | static ssize_t memory_oom_group_write(struct kernfs_open_file *of, | |
6447 | char *buf, size_t nbytes, loff_t off) | |
6448 | { | |
6449 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6450 | int ret, oom_group; | |
6451 | ||
6452 | buf = strstrip(buf); | |
6453 | if (!buf) | |
6454 | return -EINVAL; | |
6455 | ||
6456 | ret = kstrtoint(buf, 0, &oom_group); | |
6457 | if (ret) | |
6458 | return ret; | |
6459 | ||
6460 | if (oom_group != 0 && oom_group != 1) | |
6461 | return -EINVAL; | |
6462 | ||
6463 | memcg->oom_group = oom_group; | |
6464 | ||
6465 | return nbytes; | |
6466 | } | |
6467 | ||
94968384 SB |
6468 | static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf, |
6469 | size_t nbytes, loff_t off) | |
6470 | { | |
6471 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6472 | unsigned int nr_retries = MAX_RECLAIM_RETRIES; | |
6473 | unsigned long nr_to_reclaim, nr_reclaimed = 0; | |
6474 | int err; | |
6475 | ||
6476 | buf = strstrip(buf); | |
6477 | err = page_counter_memparse(buf, "", &nr_to_reclaim); | |
6478 | if (err) | |
6479 | return err; | |
6480 | ||
6481 | while (nr_reclaimed < nr_to_reclaim) { | |
6482 | unsigned long reclaimed; | |
6483 | ||
6484 | if (signal_pending(current)) | |
6485 | return -EINTR; | |
6486 | ||
6487 | /* | |
6488 | * This is the final attempt, drain percpu lru caches in the | |
6489 | * hope of introducing more evictable pages for | |
6490 | * try_to_free_mem_cgroup_pages(). | |
6491 | */ | |
6492 | if (!nr_retries) | |
6493 | lru_add_drain_all(); | |
6494 | ||
6495 | reclaimed = try_to_free_mem_cgroup_pages(memcg, | |
6496 | nr_to_reclaim - nr_reclaimed, | |
6497 | GFP_KERNEL, true); | |
6498 | ||
6499 | if (!reclaimed && !nr_retries--) | |
6500 | return -EAGAIN; | |
6501 | ||
6502 | nr_reclaimed += reclaimed; | |
6503 | } | |
6504 | ||
6505 | return nbytes; | |
6506 | } | |
6507 | ||
241994ed JW |
6508 | static struct cftype memory_files[] = { |
6509 | { | |
6510 | .name = "current", | |
f5fc3c5d | 6511 | .flags = CFTYPE_NOT_ON_ROOT, |
241994ed JW |
6512 | .read_u64 = memory_current_read, |
6513 | }, | |
8e20d4b3 GR |
6514 | { |
6515 | .name = "peak", | |
6516 | .flags = CFTYPE_NOT_ON_ROOT, | |
6517 | .read_u64 = memory_peak_read, | |
6518 | }, | |
bf8d5d52 RG |
6519 | { |
6520 | .name = "min", | |
6521 | .flags = CFTYPE_NOT_ON_ROOT, | |
6522 | .seq_show = memory_min_show, | |
6523 | .write = memory_min_write, | |
6524 | }, | |
241994ed JW |
6525 | { |
6526 | .name = "low", | |
6527 | .flags = CFTYPE_NOT_ON_ROOT, | |
6528 | .seq_show = memory_low_show, | |
6529 | .write = memory_low_write, | |
6530 | }, | |
6531 | { | |
6532 | .name = "high", | |
6533 | .flags = CFTYPE_NOT_ON_ROOT, | |
6534 | .seq_show = memory_high_show, | |
6535 | .write = memory_high_write, | |
6536 | }, | |
6537 | { | |
6538 | .name = "max", | |
6539 | .flags = CFTYPE_NOT_ON_ROOT, | |
6540 | .seq_show = memory_max_show, | |
6541 | .write = memory_max_write, | |
6542 | }, | |
6543 | { | |
6544 | .name = "events", | |
6545 | .flags = CFTYPE_NOT_ON_ROOT, | |
472912a2 | 6546 | .file_offset = offsetof(struct mem_cgroup, events_file), |
241994ed JW |
6547 | .seq_show = memory_events_show, |
6548 | }, | |
1e577f97 SB |
6549 | { |
6550 | .name = "events.local", | |
6551 | .flags = CFTYPE_NOT_ON_ROOT, | |
6552 | .file_offset = offsetof(struct mem_cgroup, events_local_file), | |
6553 | .seq_show = memory_events_local_show, | |
6554 | }, | |
587d9f72 JW |
6555 | { |
6556 | .name = "stat", | |
587d9f72 JW |
6557 | .seq_show = memory_stat_show, |
6558 | }, | |
5f9a4f4a MS |
6559 | #ifdef CONFIG_NUMA |
6560 | { | |
6561 | .name = "numa_stat", | |
6562 | .seq_show = memory_numa_stat_show, | |
6563 | }, | |
6564 | #endif | |
3d8b38eb RG |
6565 | { |
6566 | .name = "oom.group", | |
6567 | .flags = CFTYPE_NOT_ON_ROOT | CFTYPE_NS_DELEGATABLE, | |
6568 | .seq_show = memory_oom_group_show, | |
6569 | .write = memory_oom_group_write, | |
6570 | }, | |
94968384 SB |
6571 | { |
6572 | .name = "reclaim", | |
6573 | .flags = CFTYPE_NS_DELEGATABLE, | |
6574 | .write = memory_reclaim, | |
6575 | }, | |
241994ed JW |
6576 | { } /* terminate */ |
6577 | }; | |
6578 | ||
073219e9 | 6579 | struct cgroup_subsys memory_cgrp_subsys = { |
92fb9748 | 6580 | .css_alloc = mem_cgroup_css_alloc, |
d142e3e6 | 6581 | .css_online = mem_cgroup_css_online, |
92fb9748 | 6582 | .css_offline = mem_cgroup_css_offline, |
6df38689 | 6583 | .css_released = mem_cgroup_css_released, |
92fb9748 | 6584 | .css_free = mem_cgroup_css_free, |
1ced953b | 6585 | .css_reset = mem_cgroup_css_reset, |
2d146aa3 | 6586 | .css_rstat_flush = mem_cgroup_css_rstat_flush, |
7dc74be0 DN |
6587 | .can_attach = mem_cgroup_can_attach, |
6588 | .cancel_attach = mem_cgroup_cancel_attach, | |
264a0ae1 | 6589 | .post_attach = mem_cgroup_move_task, |
241994ed JW |
6590 | .dfl_cftypes = memory_files, |
6591 | .legacy_cftypes = mem_cgroup_legacy_files, | |
6d12e2d8 | 6592 | .early_init = 0, |
8cdea7c0 | 6593 | }; |
c077719b | 6594 | |
bc50bcc6 JW |
6595 | /* |
6596 | * This function calculates an individual cgroup's effective | |
6597 | * protection which is derived from its own memory.min/low, its | |
6598 | * parent's and siblings' settings, as well as the actual memory | |
6599 | * distribution in the tree. | |
6600 | * | |
6601 | * The following rules apply to the effective protection values: | |
6602 | * | |
6603 | * 1. At the first level of reclaim, effective protection is equal to | |
6604 | * the declared protection in memory.min and memory.low. | |
6605 | * | |
6606 | * 2. To enable safe delegation of the protection configuration, at | |
6607 | * subsequent levels the effective protection is capped to the | |
6608 | * parent's effective protection. | |
6609 | * | |
6610 | * 3. To make complex and dynamic subtrees easier to configure, the | |
6611 | * user is allowed to overcommit the declared protection at a given | |
6612 | * level. If that is the case, the parent's effective protection is | |
6613 | * distributed to the children in proportion to how much protection | |
6614 | * they have declared and how much of it they are utilizing. | |
6615 | * | |
6616 | * This makes distribution proportional, but also work-conserving: | |
6617 | * if one cgroup claims much more protection than it uses memory, | |
6618 | * the unused remainder is available to its siblings. | |
6619 | * | |
6620 | * 4. Conversely, when the declared protection is undercommitted at a | |
6621 | * given level, the distribution of the larger parental protection | |
6622 | * budget is NOT proportional. A cgroup's protection from a sibling | |
6623 | * is capped to its own memory.min/low setting. | |
6624 | * | |
8a931f80 JW |
6625 | * 5. However, to allow protecting recursive subtrees from each other |
6626 | * without having to declare each individual cgroup's fixed share | |
6627 | * of the ancestor's claim to protection, any unutilized - | |
6628 | * "floating" - protection from up the tree is distributed in | |
6629 | * proportion to each cgroup's *usage*. This makes the protection | |
6630 | * neutral wrt sibling cgroups and lets them compete freely over | |
6631 | * the shared parental protection budget, but it protects the | |
6632 | * subtree as a whole from neighboring subtrees. | |
6633 | * | |
6634 | * Note that 4. and 5. are not in conflict: 4. is about protecting | |
6635 | * against immediate siblings whereas 5. is about protecting against | |
6636 | * neighboring subtrees. | |
bc50bcc6 JW |
6637 | */ |
6638 | static unsigned long effective_protection(unsigned long usage, | |
8a931f80 | 6639 | unsigned long parent_usage, |
bc50bcc6 JW |
6640 | unsigned long setting, |
6641 | unsigned long parent_effective, | |
6642 | unsigned long siblings_protected) | |
6643 | { | |
6644 | unsigned long protected; | |
8a931f80 | 6645 | unsigned long ep; |
bc50bcc6 JW |
6646 | |
6647 | protected = min(usage, setting); | |
6648 | /* | |
6649 | * If all cgroups at this level combined claim and use more | |
6650 | * protection then what the parent affords them, distribute | |
6651 | * shares in proportion to utilization. | |
6652 | * | |
6653 | * We are using actual utilization rather than the statically | |
6654 | * claimed protection in order to be work-conserving: claimed | |
6655 | * but unused protection is available to siblings that would | |
6656 | * otherwise get a smaller chunk than what they claimed. | |
6657 | */ | |
6658 | if (siblings_protected > parent_effective) | |
6659 | return protected * parent_effective / siblings_protected; | |
6660 | ||
6661 | /* | |
6662 | * Ok, utilized protection of all children is within what the | |
6663 | * parent affords them, so we know whatever this child claims | |
6664 | * and utilizes is effectively protected. | |
6665 | * | |
6666 | * If there is unprotected usage beyond this value, reclaim | |
6667 | * will apply pressure in proportion to that amount. | |
6668 | * | |
6669 | * If there is unutilized protection, the cgroup will be fully | |
6670 | * shielded from reclaim, but we do return a smaller value for | |
6671 | * protection than what the group could enjoy in theory. This | |
6672 | * is okay. With the overcommit distribution above, effective | |
6673 | * protection is always dependent on how memory is actually | |
6674 | * consumed among the siblings anyway. | |
6675 | */ | |
8a931f80 JW |
6676 | ep = protected; |
6677 | ||
6678 | /* | |
6679 | * If the children aren't claiming (all of) the protection | |
6680 | * afforded to them by the parent, distribute the remainder in | |
6681 | * proportion to the (unprotected) memory of each cgroup. That | |
6682 | * way, cgroups that aren't explicitly prioritized wrt each | |
6683 | * other compete freely over the allowance, but they are | |
6684 | * collectively protected from neighboring trees. | |
6685 | * | |
6686 | * We're using unprotected memory for the weight so that if | |
6687 | * some cgroups DO claim explicit protection, we don't protect | |
6688 | * the same bytes twice. | |
cd324edc JW |
6689 | * |
6690 | * Check both usage and parent_usage against the respective | |
6691 | * protected values. One should imply the other, but they | |
6692 | * aren't read atomically - make sure the division is sane. | |
8a931f80 JW |
6693 | */ |
6694 | if (!(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_RECURSIVE_PROT)) | |
6695 | return ep; | |
cd324edc JW |
6696 | if (parent_effective > siblings_protected && |
6697 | parent_usage > siblings_protected && | |
6698 | usage > protected) { | |
8a931f80 JW |
6699 | unsigned long unclaimed; |
6700 | ||
6701 | unclaimed = parent_effective - siblings_protected; | |
6702 | unclaimed *= usage - protected; | |
6703 | unclaimed /= parent_usage - siblings_protected; | |
6704 | ||
6705 | ep += unclaimed; | |
6706 | } | |
6707 | ||
6708 | return ep; | |
bc50bcc6 JW |
6709 | } |
6710 | ||
241994ed | 6711 | /** |
05395718 | 6712 | * mem_cgroup_calculate_protection - check if memory consumption is in the normal range |
34c81057 | 6713 | * @root: the top ancestor of the sub-tree being checked |
241994ed JW |
6714 | * @memcg: the memory cgroup to check |
6715 | * | |
23067153 RG |
6716 | * WARNING: This function is not stateless! It can only be used as part |
6717 | * of a top-down tree iteration, not for isolated queries. | |
241994ed | 6718 | */ |
45c7f7e1 CD |
6719 | void mem_cgroup_calculate_protection(struct mem_cgroup *root, |
6720 | struct mem_cgroup *memcg) | |
241994ed | 6721 | { |
8a931f80 | 6722 | unsigned long usage, parent_usage; |
23067153 RG |
6723 | struct mem_cgroup *parent; |
6724 | ||
241994ed | 6725 | if (mem_cgroup_disabled()) |
45c7f7e1 | 6726 | return; |
241994ed | 6727 | |
34c81057 SC |
6728 | if (!root) |
6729 | root = root_mem_cgroup; | |
22f7496f YS |
6730 | |
6731 | /* | |
6732 | * Effective values of the reclaim targets are ignored so they | |
6733 | * can be stale. Have a look at mem_cgroup_protection for more | |
6734 | * details. | |
6735 | * TODO: calculation should be more robust so that we do not need | |
6736 | * that special casing. | |
6737 | */ | |
34c81057 | 6738 | if (memcg == root) |
45c7f7e1 | 6739 | return; |
241994ed | 6740 | |
23067153 | 6741 | usage = page_counter_read(&memcg->memory); |
bf8d5d52 | 6742 | if (!usage) |
45c7f7e1 | 6743 | return; |
bf8d5d52 | 6744 | |
bf8d5d52 | 6745 | parent = parent_mem_cgroup(memcg); |
df2a4196 | 6746 | |
bc50bcc6 | 6747 | if (parent == root) { |
c3d53200 | 6748 | memcg->memory.emin = READ_ONCE(memcg->memory.min); |
03960e33 | 6749 | memcg->memory.elow = READ_ONCE(memcg->memory.low); |
45c7f7e1 | 6750 | return; |
bf8d5d52 RG |
6751 | } |
6752 | ||
8a931f80 JW |
6753 | parent_usage = page_counter_read(&parent->memory); |
6754 | ||
b3a7822e | 6755 | WRITE_ONCE(memcg->memory.emin, effective_protection(usage, parent_usage, |
c3d53200 CD |
6756 | READ_ONCE(memcg->memory.min), |
6757 | READ_ONCE(parent->memory.emin), | |
b3a7822e | 6758 | atomic_long_read(&parent->memory.children_min_usage))); |
23067153 | 6759 | |
b3a7822e | 6760 | WRITE_ONCE(memcg->memory.elow, effective_protection(usage, parent_usage, |
03960e33 CD |
6761 | READ_ONCE(memcg->memory.low), |
6762 | READ_ONCE(parent->memory.elow), | |
b3a7822e | 6763 | atomic_long_read(&parent->memory.children_low_usage))); |
241994ed JW |
6764 | } |
6765 | ||
8f425e4e MWO |
6766 | static int charge_memcg(struct folio *folio, struct mem_cgroup *memcg, |
6767 | gfp_t gfp) | |
0add0c77 | 6768 | { |
118f2875 | 6769 | long nr_pages = folio_nr_pages(folio); |
0add0c77 SB |
6770 | int ret; |
6771 | ||
6772 | ret = try_charge(memcg, gfp, nr_pages); | |
6773 | if (ret) | |
6774 | goto out; | |
6775 | ||
6776 | css_get(&memcg->css); | |
118f2875 | 6777 | commit_charge(folio, memcg); |
0add0c77 SB |
6778 | |
6779 | local_irq_disable(); | |
6e0110c2 | 6780 | mem_cgroup_charge_statistics(memcg, nr_pages); |
8f425e4e | 6781 | memcg_check_events(memcg, folio_nid(folio)); |
0add0c77 SB |
6782 | local_irq_enable(); |
6783 | out: | |
6784 | return ret; | |
6785 | } | |
6786 | ||
8f425e4e | 6787 | int __mem_cgroup_charge(struct folio *folio, struct mm_struct *mm, gfp_t gfp) |
00501b53 | 6788 | { |
0add0c77 SB |
6789 | struct mem_cgroup *memcg; |
6790 | int ret; | |
00501b53 | 6791 | |
0add0c77 | 6792 | memcg = get_mem_cgroup_from_mm(mm); |
8f425e4e | 6793 | ret = charge_memcg(folio, memcg, gfp); |
0add0c77 | 6794 | css_put(&memcg->css); |
2d1c4980 | 6795 | |
0add0c77 SB |
6796 | return ret; |
6797 | } | |
e993d905 | 6798 | |
0add0c77 SB |
6799 | /** |
6800 | * mem_cgroup_swapin_charge_page - charge a newly allocated page for swapin | |
6801 | * @page: page to charge | |
6802 | * @mm: mm context of the victim | |
6803 | * @gfp: reclaim mode | |
6804 | * @entry: swap entry for which the page is allocated | |
6805 | * | |
6806 | * This function charges a page allocated for swapin. Please call this before | |
6807 | * adding the page to the swapcache. | |
6808 | * | |
6809 | * Returns 0 on success. Otherwise, an error code is returned. | |
6810 | */ | |
6811 | int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm, | |
6812 | gfp_t gfp, swp_entry_t entry) | |
6813 | { | |
8f425e4e | 6814 | struct folio *folio = page_folio(page); |
0add0c77 SB |
6815 | struct mem_cgroup *memcg; |
6816 | unsigned short id; | |
6817 | int ret; | |
00501b53 | 6818 | |
0add0c77 SB |
6819 | if (mem_cgroup_disabled()) |
6820 | return 0; | |
00501b53 | 6821 | |
0add0c77 SB |
6822 | id = lookup_swap_cgroup_id(entry); |
6823 | rcu_read_lock(); | |
6824 | memcg = mem_cgroup_from_id(id); | |
6825 | if (!memcg || !css_tryget_online(&memcg->css)) | |
6826 | memcg = get_mem_cgroup_from_mm(mm); | |
6827 | rcu_read_unlock(); | |
00501b53 | 6828 | |
8f425e4e | 6829 | ret = charge_memcg(folio, memcg, gfp); |
6abb5a86 | 6830 | |
0add0c77 SB |
6831 | css_put(&memcg->css); |
6832 | return ret; | |
6833 | } | |
00501b53 | 6834 | |
0add0c77 SB |
6835 | /* |
6836 | * mem_cgroup_swapin_uncharge_swap - uncharge swap slot | |
6837 | * @entry: swap entry for which the page is charged | |
6838 | * | |
6839 | * Call this function after successfully adding the charged page to swapcache. | |
6840 | * | |
6841 | * Note: This function assumes the page for which swap slot is being uncharged | |
6842 | * is order 0 page. | |
6843 | */ | |
6844 | void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry) | |
6845 | { | |
cae3af62 MS |
6846 | /* |
6847 | * Cgroup1's unified memory+swap counter has been charged with the | |
6848 | * new swapcache page, finish the transfer by uncharging the swap | |
6849 | * slot. The swap slot would also get uncharged when it dies, but | |
6850 | * it can stick around indefinitely and we'd count the page twice | |
6851 | * the entire time. | |
6852 | * | |
6853 | * Cgroup2 has separate resource counters for memory and swap, | |
6854 | * so this is a non-issue here. Memory and swap charge lifetimes | |
6855 | * correspond 1:1 to page and swap slot lifetimes: we charge the | |
6856 | * page to memory here, and uncharge swap when the slot is freed. | |
6857 | */ | |
0add0c77 | 6858 | if (!mem_cgroup_disabled() && do_memsw_account()) { |
00501b53 JW |
6859 | /* |
6860 | * The swap entry might not get freed for a long time, | |
6861 | * let's not wait for it. The page already received a | |
6862 | * memory+swap charge, drop the swap entry duplicate. | |
6863 | */ | |
0add0c77 | 6864 | mem_cgroup_uncharge_swap(entry, 1); |
00501b53 | 6865 | } |
3fea5a49 JW |
6866 | } |
6867 | ||
a9d5adee JG |
6868 | struct uncharge_gather { |
6869 | struct mem_cgroup *memcg; | |
b4e0b68f | 6870 | unsigned long nr_memory; |
a9d5adee | 6871 | unsigned long pgpgout; |
a9d5adee | 6872 | unsigned long nr_kmem; |
8e88bd2d | 6873 | int nid; |
a9d5adee JG |
6874 | }; |
6875 | ||
6876 | static inline void uncharge_gather_clear(struct uncharge_gather *ug) | |
747db954 | 6877 | { |
a9d5adee JG |
6878 | memset(ug, 0, sizeof(*ug)); |
6879 | } | |
6880 | ||
6881 | static void uncharge_batch(const struct uncharge_gather *ug) | |
6882 | { | |
747db954 JW |
6883 | unsigned long flags; |
6884 | ||
b4e0b68f MS |
6885 | if (ug->nr_memory) { |
6886 | page_counter_uncharge(&ug->memcg->memory, ug->nr_memory); | |
7941d214 | 6887 | if (do_memsw_account()) |
b4e0b68f | 6888 | page_counter_uncharge(&ug->memcg->memsw, ug->nr_memory); |
a8c49af3 YA |
6889 | if (ug->nr_kmem) |
6890 | memcg_account_kmem(ug->memcg, -ug->nr_kmem); | |
a9d5adee | 6891 | memcg_oom_recover(ug->memcg); |
ce00a967 | 6892 | } |
747db954 JW |
6893 | |
6894 | local_irq_save(flags); | |
c9019e9b | 6895 | __count_memcg_events(ug->memcg, PGPGOUT, ug->pgpgout); |
b4e0b68f | 6896 | __this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, ug->nr_memory); |
8e88bd2d | 6897 | memcg_check_events(ug->memcg, ug->nid); |
747db954 | 6898 | local_irq_restore(flags); |
f1796544 | 6899 | |
c4ed6ebf | 6900 | /* drop reference from uncharge_folio */ |
f1796544 | 6901 | css_put(&ug->memcg->css); |
a9d5adee JG |
6902 | } |
6903 | ||
c4ed6ebf | 6904 | static void uncharge_folio(struct folio *folio, struct uncharge_gather *ug) |
a9d5adee | 6905 | { |
c4ed6ebf | 6906 | long nr_pages; |
b4e0b68f MS |
6907 | struct mem_cgroup *memcg; |
6908 | struct obj_cgroup *objcg; | |
9f762dbe | 6909 | |
c4ed6ebf | 6910 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
a9d5adee | 6911 | |
a9d5adee JG |
6912 | /* |
6913 | * Nobody should be changing or seriously looking at | |
c4ed6ebf MWO |
6914 | * folio memcg or objcg at this point, we have fully |
6915 | * exclusive access to the folio. | |
a9d5adee | 6916 | */ |
fead2b86 | 6917 | if (folio_memcg_kmem(folio)) { |
1b7e4464 | 6918 | objcg = __folio_objcg(folio); |
b4e0b68f MS |
6919 | /* |
6920 | * This get matches the put at the end of the function and | |
6921 | * kmem pages do not hold memcg references anymore. | |
6922 | */ | |
6923 | memcg = get_mem_cgroup_from_objcg(objcg); | |
6924 | } else { | |
1b7e4464 | 6925 | memcg = __folio_memcg(folio); |
b4e0b68f | 6926 | } |
a9d5adee | 6927 | |
b4e0b68f MS |
6928 | if (!memcg) |
6929 | return; | |
6930 | ||
6931 | if (ug->memcg != memcg) { | |
a9d5adee JG |
6932 | if (ug->memcg) { |
6933 | uncharge_batch(ug); | |
6934 | uncharge_gather_clear(ug); | |
6935 | } | |
b4e0b68f | 6936 | ug->memcg = memcg; |
c4ed6ebf | 6937 | ug->nid = folio_nid(folio); |
f1796544 MH |
6938 | |
6939 | /* pairs with css_put in uncharge_batch */ | |
b4e0b68f | 6940 | css_get(&memcg->css); |
a9d5adee JG |
6941 | } |
6942 | ||
c4ed6ebf | 6943 | nr_pages = folio_nr_pages(folio); |
a9d5adee | 6944 | |
fead2b86 | 6945 | if (folio_memcg_kmem(folio)) { |
b4e0b68f | 6946 | ug->nr_memory += nr_pages; |
9f762dbe | 6947 | ug->nr_kmem += nr_pages; |
b4e0b68f | 6948 | |
c4ed6ebf | 6949 | folio->memcg_data = 0; |
b4e0b68f MS |
6950 | obj_cgroup_put(objcg); |
6951 | } else { | |
6952 | /* LRU pages aren't accounted at the root level */ | |
6953 | if (!mem_cgroup_is_root(memcg)) | |
6954 | ug->nr_memory += nr_pages; | |
18b2db3b | 6955 | ug->pgpgout++; |
a9d5adee | 6956 | |
c4ed6ebf | 6957 | folio->memcg_data = 0; |
b4e0b68f MS |
6958 | } |
6959 | ||
6960 | css_put(&memcg->css); | |
747db954 JW |
6961 | } |
6962 | ||
bbc6b703 | 6963 | void __mem_cgroup_uncharge(struct folio *folio) |
0a31bc97 | 6964 | { |
a9d5adee JG |
6965 | struct uncharge_gather ug; |
6966 | ||
bbc6b703 MWO |
6967 | /* Don't touch folio->lru of any random page, pre-check: */ |
6968 | if (!folio_memcg(folio)) | |
0a31bc97 JW |
6969 | return; |
6970 | ||
a9d5adee | 6971 | uncharge_gather_clear(&ug); |
bbc6b703 | 6972 | uncharge_folio(folio, &ug); |
a9d5adee | 6973 | uncharge_batch(&ug); |
747db954 | 6974 | } |
0a31bc97 | 6975 | |
747db954 | 6976 | /** |
2c8d8f97 | 6977 | * __mem_cgroup_uncharge_list - uncharge a list of page |
747db954 JW |
6978 | * @page_list: list of pages to uncharge |
6979 | * | |
6980 | * Uncharge a list of pages previously charged with | |
2c8d8f97 | 6981 | * __mem_cgroup_charge(). |
747db954 | 6982 | */ |
2c8d8f97 | 6983 | void __mem_cgroup_uncharge_list(struct list_head *page_list) |
747db954 | 6984 | { |
c41a40b6 | 6985 | struct uncharge_gather ug; |
c4ed6ebf | 6986 | struct folio *folio; |
c41a40b6 | 6987 | |
c41a40b6 | 6988 | uncharge_gather_clear(&ug); |
c4ed6ebf MWO |
6989 | list_for_each_entry(folio, page_list, lru) |
6990 | uncharge_folio(folio, &ug); | |
c41a40b6 MS |
6991 | if (ug.memcg) |
6992 | uncharge_batch(&ug); | |
0a31bc97 JW |
6993 | } |
6994 | ||
6995 | /** | |
d21bba2b MWO |
6996 | * mem_cgroup_migrate - Charge a folio's replacement. |
6997 | * @old: Currently circulating folio. | |
6998 | * @new: Replacement folio. | |
0a31bc97 | 6999 | * |
d21bba2b | 7000 | * Charge @new as a replacement folio for @old. @old will |
6a93ca8f | 7001 | * be uncharged upon free. |
0a31bc97 | 7002 | * |
d21bba2b | 7003 | * Both folios must be locked, @new->mapping must be set up. |
0a31bc97 | 7004 | */ |
d21bba2b | 7005 | void mem_cgroup_migrate(struct folio *old, struct folio *new) |
0a31bc97 | 7006 | { |
29833315 | 7007 | struct mem_cgroup *memcg; |
d21bba2b | 7008 | long nr_pages = folio_nr_pages(new); |
d93c4130 | 7009 | unsigned long flags; |
0a31bc97 | 7010 | |
d21bba2b MWO |
7011 | VM_BUG_ON_FOLIO(!folio_test_locked(old), old); |
7012 | VM_BUG_ON_FOLIO(!folio_test_locked(new), new); | |
7013 | VM_BUG_ON_FOLIO(folio_test_anon(old) != folio_test_anon(new), new); | |
7014 | VM_BUG_ON_FOLIO(folio_nr_pages(old) != nr_pages, new); | |
0a31bc97 JW |
7015 | |
7016 | if (mem_cgroup_disabled()) | |
7017 | return; | |
7018 | ||
d21bba2b MWO |
7019 | /* Page cache replacement: new folio already charged? */ |
7020 | if (folio_memcg(new)) | |
0a31bc97 JW |
7021 | return; |
7022 | ||
d21bba2b MWO |
7023 | memcg = folio_memcg(old); |
7024 | VM_WARN_ON_ONCE_FOLIO(!memcg, old); | |
29833315 | 7025 | if (!memcg) |
0a31bc97 JW |
7026 | return; |
7027 | ||
44b7a8d3 | 7028 | /* Force-charge the new page. The old one will be freed soon */ |
8dc87c7d MS |
7029 | if (!mem_cgroup_is_root(memcg)) { |
7030 | page_counter_charge(&memcg->memory, nr_pages); | |
7031 | if (do_memsw_account()) | |
7032 | page_counter_charge(&memcg->memsw, nr_pages); | |
7033 | } | |
0a31bc97 | 7034 | |
1a3e1f40 | 7035 | css_get(&memcg->css); |
d21bba2b | 7036 | commit_charge(new, memcg); |
44b7a8d3 | 7037 | |
d93c4130 | 7038 | local_irq_save(flags); |
6e0110c2 | 7039 | mem_cgroup_charge_statistics(memcg, nr_pages); |
d21bba2b | 7040 | memcg_check_events(memcg, folio_nid(new)); |
d93c4130 | 7041 | local_irq_restore(flags); |
0a31bc97 JW |
7042 | } |
7043 | ||
ef12947c | 7044 | DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key); |
11092087 JW |
7045 | EXPORT_SYMBOL(memcg_sockets_enabled_key); |
7046 | ||
2d758073 | 7047 | void mem_cgroup_sk_alloc(struct sock *sk) |
11092087 JW |
7048 | { |
7049 | struct mem_cgroup *memcg; | |
7050 | ||
2d758073 JW |
7051 | if (!mem_cgroup_sockets_enabled) |
7052 | return; | |
7053 | ||
e876ecc6 | 7054 | /* Do not associate the sock with unrelated interrupted task's memcg. */ |
086f694a | 7055 | if (!in_task()) |
e876ecc6 SB |
7056 | return; |
7057 | ||
11092087 JW |
7058 | rcu_read_lock(); |
7059 | memcg = mem_cgroup_from_task(current); | |
f7e1cb6e JW |
7060 | if (memcg == root_mem_cgroup) |
7061 | goto out; | |
0db15298 | 7062 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcpmem_active) |
f7e1cb6e | 7063 | goto out; |
8965aa28 | 7064 | if (css_tryget(&memcg->css)) |
11092087 | 7065 | sk->sk_memcg = memcg; |
f7e1cb6e | 7066 | out: |
11092087 JW |
7067 | rcu_read_unlock(); |
7068 | } | |
11092087 | 7069 | |
2d758073 | 7070 | void mem_cgroup_sk_free(struct sock *sk) |
11092087 | 7071 | { |
2d758073 JW |
7072 | if (sk->sk_memcg) |
7073 | css_put(&sk->sk_memcg->css); | |
11092087 JW |
7074 | } |
7075 | ||
7076 | /** | |
7077 | * mem_cgroup_charge_skmem - charge socket memory | |
7078 | * @memcg: memcg to charge | |
7079 | * @nr_pages: number of pages to charge | |
4b1327be | 7080 | * @gfp_mask: reclaim mode |
11092087 JW |
7081 | * |
7082 | * Charges @nr_pages to @memcg. Returns %true if the charge fit within | |
4b1327be | 7083 | * @memcg's configured limit, %false if it doesn't. |
11092087 | 7084 | */ |
4b1327be WW |
7085 | bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages, |
7086 | gfp_t gfp_mask) | |
11092087 | 7087 | { |
f7e1cb6e | 7088 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 7089 | struct page_counter *fail; |
f7e1cb6e | 7090 | |
0db15298 JW |
7091 | if (page_counter_try_charge(&memcg->tcpmem, nr_pages, &fail)) { |
7092 | memcg->tcpmem_pressure = 0; | |
f7e1cb6e JW |
7093 | return true; |
7094 | } | |
0db15298 | 7095 | memcg->tcpmem_pressure = 1; |
4b1327be WW |
7096 | if (gfp_mask & __GFP_NOFAIL) { |
7097 | page_counter_charge(&memcg->tcpmem, nr_pages); | |
7098 | return true; | |
7099 | } | |
f7e1cb6e | 7100 | return false; |
11092087 | 7101 | } |
d886f4e4 | 7102 | |
4b1327be WW |
7103 | if (try_charge(memcg, gfp_mask, nr_pages) == 0) { |
7104 | mod_memcg_state(memcg, MEMCG_SOCK, nr_pages); | |
f7e1cb6e | 7105 | return true; |
4b1327be | 7106 | } |
f7e1cb6e | 7107 | |
11092087 JW |
7108 | return false; |
7109 | } | |
7110 | ||
7111 | /** | |
7112 | * mem_cgroup_uncharge_skmem - uncharge socket memory | |
b7701a5f MR |
7113 | * @memcg: memcg to uncharge |
7114 | * @nr_pages: number of pages to uncharge | |
11092087 JW |
7115 | */ |
7116 | void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) | |
7117 | { | |
f7e1cb6e | 7118 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 7119 | page_counter_uncharge(&memcg->tcpmem, nr_pages); |
f7e1cb6e JW |
7120 | return; |
7121 | } | |
d886f4e4 | 7122 | |
c9019e9b | 7123 | mod_memcg_state(memcg, MEMCG_SOCK, -nr_pages); |
b2807f07 | 7124 | |
475d0487 | 7125 | refill_stock(memcg, nr_pages); |
11092087 JW |
7126 | } |
7127 | ||
f7e1cb6e JW |
7128 | static int __init cgroup_memory(char *s) |
7129 | { | |
7130 | char *token; | |
7131 | ||
7132 | while ((token = strsep(&s, ",")) != NULL) { | |
7133 | if (!*token) | |
7134 | continue; | |
7135 | if (!strcmp(token, "nosocket")) | |
7136 | cgroup_memory_nosocket = true; | |
04823c83 VD |
7137 | if (!strcmp(token, "nokmem")) |
7138 | cgroup_memory_nokmem = true; | |
f7e1cb6e | 7139 | } |
460a79e1 | 7140 | return 1; |
f7e1cb6e JW |
7141 | } |
7142 | __setup("cgroup.memory=", cgroup_memory); | |
11092087 | 7143 | |
2d11085e | 7144 | /* |
1081312f MH |
7145 | * subsys_initcall() for memory controller. |
7146 | * | |
308167fc SAS |
7147 | * Some parts like memcg_hotplug_cpu_dead() have to be initialized from this |
7148 | * context because of lock dependencies (cgroup_lock -> cpu hotplug) but | |
7149 | * basically everything that doesn't depend on a specific mem_cgroup structure | |
7150 | * should be initialized from here. | |
2d11085e MH |
7151 | */ |
7152 | static int __init mem_cgroup_init(void) | |
7153 | { | |
95a045f6 JW |
7154 | int cpu, node; |
7155 | ||
f3344adf MS |
7156 | /* |
7157 | * Currently s32 type (can refer to struct batched_lruvec_stat) is | |
7158 | * used for per-memcg-per-cpu caching of per-node statistics. In order | |
7159 | * to work fine, we should make sure that the overfill threshold can't | |
7160 | * exceed S32_MAX / PAGE_SIZE. | |
7161 | */ | |
7162 | BUILD_BUG_ON(MEMCG_CHARGE_BATCH > S32_MAX / PAGE_SIZE); | |
7163 | ||
308167fc SAS |
7164 | cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL, |
7165 | memcg_hotplug_cpu_dead); | |
95a045f6 JW |
7166 | |
7167 | for_each_possible_cpu(cpu) | |
7168 | INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work, | |
7169 | drain_local_stock); | |
7170 | ||
7171 | for_each_node(node) { | |
7172 | struct mem_cgroup_tree_per_node *rtpn; | |
95a045f6 JW |
7173 | |
7174 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, | |
7175 | node_online(node) ? node : NUMA_NO_NODE); | |
7176 | ||
ef8f2327 | 7177 | rtpn->rb_root = RB_ROOT; |
fa90b2fd | 7178 | rtpn->rb_rightmost = NULL; |
ef8f2327 | 7179 | spin_lock_init(&rtpn->lock); |
95a045f6 JW |
7180 | soft_limit_tree.rb_tree_per_node[node] = rtpn; |
7181 | } | |
7182 | ||
2d11085e MH |
7183 | return 0; |
7184 | } | |
7185 | subsys_initcall(mem_cgroup_init); | |
21afa38e JW |
7186 | |
7187 | #ifdef CONFIG_MEMCG_SWAP | |
358c07fc AB |
7188 | static struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg) |
7189 | { | |
1c2d479a | 7190 | while (!refcount_inc_not_zero(&memcg->id.ref)) { |
358c07fc AB |
7191 | /* |
7192 | * The root cgroup cannot be destroyed, so it's refcount must | |
7193 | * always be >= 1. | |
7194 | */ | |
7195 | if (WARN_ON_ONCE(memcg == root_mem_cgroup)) { | |
7196 | VM_BUG_ON(1); | |
7197 | break; | |
7198 | } | |
7199 | memcg = parent_mem_cgroup(memcg); | |
7200 | if (!memcg) | |
7201 | memcg = root_mem_cgroup; | |
7202 | } | |
7203 | return memcg; | |
7204 | } | |
7205 | ||
21afa38e JW |
7206 | /** |
7207 | * mem_cgroup_swapout - transfer a memsw charge to swap | |
3ecb0087 | 7208 | * @folio: folio whose memsw charge to transfer |
21afa38e JW |
7209 | * @entry: swap entry to move the charge to |
7210 | * | |
3ecb0087 | 7211 | * Transfer the memsw charge of @folio to @entry. |
21afa38e | 7212 | */ |
3ecb0087 | 7213 | void mem_cgroup_swapout(struct folio *folio, swp_entry_t entry) |
21afa38e | 7214 | { |
1f47b61f | 7215 | struct mem_cgroup *memcg, *swap_memcg; |
d6810d73 | 7216 | unsigned int nr_entries; |
21afa38e JW |
7217 | unsigned short oldid; |
7218 | ||
3ecb0087 MWO |
7219 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
7220 | VM_BUG_ON_FOLIO(folio_ref_count(folio), folio); | |
21afa38e | 7221 | |
76358ab5 AS |
7222 | if (mem_cgroup_disabled()) |
7223 | return; | |
7224 | ||
2d1c4980 | 7225 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
21afa38e JW |
7226 | return; |
7227 | ||
3ecb0087 | 7228 | memcg = folio_memcg(folio); |
21afa38e | 7229 | |
3ecb0087 | 7230 | VM_WARN_ON_ONCE_FOLIO(!memcg, folio); |
21afa38e JW |
7231 | if (!memcg) |
7232 | return; | |
7233 | ||
1f47b61f VD |
7234 | /* |
7235 | * In case the memcg owning these pages has been offlined and doesn't | |
7236 | * have an ID allocated to it anymore, charge the closest online | |
7237 | * ancestor for the swap instead and transfer the memory+swap charge. | |
7238 | */ | |
7239 | swap_memcg = mem_cgroup_id_get_online(memcg); | |
3ecb0087 | 7240 | nr_entries = folio_nr_pages(folio); |
d6810d73 HY |
7241 | /* Get references for the tail pages, too */ |
7242 | if (nr_entries > 1) | |
7243 | mem_cgroup_id_get_many(swap_memcg, nr_entries - 1); | |
7244 | oldid = swap_cgroup_record(entry, mem_cgroup_id(swap_memcg), | |
7245 | nr_entries); | |
3ecb0087 | 7246 | VM_BUG_ON_FOLIO(oldid, folio); |
c9019e9b | 7247 | mod_memcg_state(swap_memcg, MEMCG_SWAP, nr_entries); |
21afa38e | 7248 | |
3ecb0087 | 7249 | folio->memcg_data = 0; |
21afa38e JW |
7250 | |
7251 | if (!mem_cgroup_is_root(memcg)) | |
d6810d73 | 7252 | page_counter_uncharge(&memcg->memory, nr_entries); |
21afa38e | 7253 | |
2d1c4980 | 7254 | if (!cgroup_memory_noswap && memcg != swap_memcg) { |
1f47b61f | 7255 | if (!mem_cgroup_is_root(swap_memcg)) |
d6810d73 HY |
7256 | page_counter_charge(&swap_memcg->memsw, nr_entries); |
7257 | page_counter_uncharge(&memcg->memsw, nr_entries); | |
1f47b61f VD |
7258 | } |
7259 | ||
ce9ce665 SAS |
7260 | /* |
7261 | * Interrupts should be disabled here because the caller holds the | |
b93b0163 | 7262 | * i_pages lock which is taken with interrupts-off. It is |
ce9ce665 | 7263 | * important here to have the interrupts disabled because it is the |
b93b0163 | 7264 | * only synchronisation we have for updating the per-CPU variables. |
ce9ce665 | 7265 | */ |
be3e67b5 | 7266 | memcg_stats_lock(); |
6e0110c2 | 7267 | mem_cgroup_charge_statistics(memcg, -nr_entries); |
be3e67b5 | 7268 | memcg_stats_unlock(); |
3ecb0087 | 7269 | memcg_check_events(memcg, folio_nid(folio)); |
73f576c0 | 7270 | |
1a3e1f40 | 7271 | css_put(&memcg->css); |
21afa38e JW |
7272 | } |
7273 | ||
38d8b4e6 | 7274 | /** |
e2e3fdc7 MWO |
7275 | * __mem_cgroup_try_charge_swap - try charging swap space for a folio |
7276 | * @folio: folio being added to swap | |
37e84351 VD |
7277 | * @entry: swap entry to charge |
7278 | * | |
e2e3fdc7 | 7279 | * Try to charge @folio's memcg for the swap space at @entry. |
37e84351 VD |
7280 | * |
7281 | * Returns 0 on success, -ENOMEM on failure. | |
7282 | */ | |
e2e3fdc7 | 7283 | int __mem_cgroup_try_charge_swap(struct folio *folio, swp_entry_t entry) |
37e84351 | 7284 | { |
e2e3fdc7 | 7285 | unsigned int nr_pages = folio_nr_pages(folio); |
37e84351 | 7286 | struct page_counter *counter; |
38d8b4e6 | 7287 | struct mem_cgroup *memcg; |
37e84351 VD |
7288 | unsigned short oldid; |
7289 | ||
2d1c4980 | 7290 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
37e84351 VD |
7291 | return 0; |
7292 | ||
e2e3fdc7 | 7293 | memcg = folio_memcg(folio); |
37e84351 | 7294 | |
e2e3fdc7 | 7295 | VM_WARN_ON_ONCE_FOLIO(!memcg, folio); |
37e84351 VD |
7296 | if (!memcg) |
7297 | return 0; | |
7298 | ||
f3a53a3a TH |
7299 | if (!entry.val) { |
7300 | memcg_memory_event(memcg, MEMCG_SWAP_FAIL); | |
bb98f2c5 | 7301 | return 0; |
f3a53a3a | 7302 | } |
bb98f2c5 | 7303 | |
1f47b61f VD |
7304 | memcg = mem_cgroup_id_get_online(memcg); |
7305 | ||
2d1c4980 | 7306 | if (!cgroup_memory_noswap && !mem_cgroup_is_root(memcg) && |
38d8b4e6 | 7307 | !page_counter_try_charge(&memcg->swap, nr_pages, &counter)) { |
f3a53a3a TH |
7308 | memcg_memory_event(memcg, MEMCG_SWAP_MAX); |
7309 | memcg_memory_event(memcg, MEMCG_SWAP_FAIL); | |
1f47b61f | 7310 | mem_cgroup_id_put(memcg); |
37e84351 | 7311 | return -ENOMEM; |
1f47b61f | 7312 | } |
37e84351 | 7313 | |
38d8b4e6 HY |
7314 | /* Get references for the tail pages, too */ |
7315 | if (nr_pages > 1) | |
7316 | mem_cgroup_id_get_many(memcg, nr_pages - 1); | |
7317 | oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg), nr_pages); | |
e2e3fdc7 | 7318 | VM_BUG_ON_FOLIO(oldid, folio); |
c9019e9b | 7319 | mod_memcg_state(memcg, MEMCG_SWAP, nr_pages); |
37e84351 | 7320 | |
37e84351 VD |
7321 | return 0; |
7322 | } | |
7323 | ||
21afa38e | 7324 | /** |
01c4b28c | 7325 | * __mem_cgroup_uncharge_swap - uncharge swap space |
21afa38e | 7326 | * @entry: swap entry to uncharge |
38d8b4e6 | 7327 | * @nr_pages: the amount of swap space to uncharge |
21afa38e | 7328 | */ |
01c4b28c | 7329 | void __mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages) |
21afa38e JW |
7330 | { |
7331 | struct mem_cgroup *memcg; | |
7332 | unsigned short id; | |
7333 | ||
38d8b4e6 | 7334 | id = swap_cgroup_record(entry, 0, nr_pages); |
21afa38e | 7335 | rcu_read_lock(); |
adbe427b | 7336 | memcg = mem_cgroup_from_id(id); |
21afa38e | 7337 | if (memcg) { |
2d1c4980 | 7338 | if (!cgroup_memory_noswap && !mem_cgroup_is_root(memcg)) { |
37e84351 | 7339 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
38d8b4e6 | 7340 | page_counter_uncharge(&memcg->swap, nr_pages); |
37e84351 | 7341 | else |
38d8b4e6 | 7342 | page_counter_uncharge(&memcg->memsw, nr_pages); |
37e84351 | 7343 | } |
c9019e9b | 7344 | mod_memcg_state(memcg, MEMCG_SWAP, -nr_pages); |
38d8b4e6 | 7345 | mem_cgroup_id_put_many(memcg, nr_pages); |
21afa38e JW |
7346 | } |
7347 | rcu_read_unlock(); | |
7348 | } | |
7349 | ||
d8b38438 VD |
7350 | long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg) |
7351 | { | |
7352 | long nr_swap_pages = get_nr_swap_pages(); | |
7353 | ||
eccb52e7 | 7354 | if (cgroup_memory_noswap || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
d8b38438 VD |
7355 | return nr_swap_pages; |
7356 | for (; memcg != root_mem_cgroup; memcg = parent_mem_cgroup(memcg)) | |
7357 | nr_swap_pages = min_t(long, nr_swap_pages, | |
bbec2e15 | 7358 | READ_ONCE(memcg->swap.max) - |
d8b38438 VD |
7359 | page_counter_read(&memcg->swap)); |
7360 | return nr_swap_pages; | |
7361 | } | |
7362 | ||
5ccc5aba VD |
7363 | bool mem_cgroup_swap_full(struct page *page) |
7364 | { | |
7365 | struct mem_cgroup *memcg; | |
7366 | ||
7367 | VM_BUG_ON_PAGE(!PageLocked(page), page); | |
7368 | ||
7369 | if (vm_swap_full()) | |
7370 | return true; | |
eccb52e7 | 7371 | if (cgroup_memory_noswap || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
5ccc5aba VD |
7372 | return false; |
7373 | ||
bcfe06bf | 7374 | memcg = page_memcg(page); |
5ccc5aba VD |
7375 | if (!memcg) |
7376 | return false; | |
7377 | ||
4b82ab4f JK |
7378 | for (; memcg != root_mem_cgroup; memcg = parent_mem_cgroup(memcg)) { |
7379 | unsigned long usage = page_counter_read(&memcg->swap); | |
7380 | ||
7381 | if (usage * 2 >= READ_ONCE(memcg->swap.high) || | |
7382 | usage * 2 >= READ_ONCE(memcg->swap.max)) | |
5ccc5aba | 7383 | return true; |
4b82ab4f | 7384 | } |
5ccc5aba VD |
7385 | |
7386 | return false; | |
7387 | } | |
7388 | ||
eccb52e7 | 7389 | static int __init setup_swap_account(char *s) |
21afa38e JW |
7390 | { |
7391 | if (!strcmp(s, "1")) | |
5ab92901 | 7392 | cgroup_memory_noswap = false; |
21afa38e | 7393 | else if (!strcmp(s, "0")) |
5ab92901 | 7394 | cgroup_memory_noswap = true; |
21afa38e JW |
7395 | return 1; |
7396 | } | |
eccb52e7 | 7397 | __setup("swapaccount=", setup_swap_account); |
21afa38e | 7398 | |
37e84351 VD |
7399 | static u64 swap_current_read(struct cgroup_subsys_state *css, |
7400 | struct cftype *cft) | |
7401 | { | |
7402 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
7403 | ||
7404 | return (u64)page_counter_read(&memcg->swap) * PAGE_SIZE; | |
7405 | } | |
7406 | ||
4b82ab4f JK |
7407 | static int swap_high_show(struct seq_file *m, void *v) |
7408 | { | |
7409 | return seq_puts_memcg_tunable(m, | |
7410 | READ_ONCE(mem_cgroup_from_seq(m)->swap.high)); | |
7411 | } | |
7412 | ||
7413 | static ssize_t swap_high_write(struct kernfs_open_file *of, | |
7414 | char *buf, size_t nbytes, loff_t off) | |
7415 | { | |
7416 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
7417 | unsigned long high; | |
7418 | int err; | |
7419 | ||
7420 | buf = strstrip(buf); | |
7421 | err = page_counter_memparse(buf, "max", &high); | |
7422 | if (err) | |
7423 | return err; | |
7424 | ||
7425 | page_counter_set_high(&memcg->swap, high); | |
7426 | ||
7427 | return nbytes; | |
7428 | } | |
7429 | ||
37e84351 VD |
7430 | static int swap_max_show(struct seq_file *m, void *v) |
7431 | { | |
677dc973 CD |
7432 | return seq_puts_memcg_tunable(m, |
7433 | READ_ONCE(mem_cgroup_from_seq(m)->swap.max)); | |
37e84351 VD |
7434 | } |
7435 | ||
7436 | static ssize_t swap_max_write(struct kernfs_open_file *of, | |
7437 | char *buf, size_t nbytes, loff_t off) | |
7438 | { | |
7439 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
7440 | unsigned long max; | |
7441 | int err; | |
7442 | ||
7443 | buf = strstrip(buf); | |
7444 | err = page_counter_memparse(buf, "max", &max); | |
7445 | if (err) | |
7446 | return err; | |
7447 | ||
be09102b | 7448 | xchg(&memcg->swap.max, max); |
37e84351 VD |
7449 | |
7450 | return nbytes; | |
7451 | } | |
7452 | ||
f3a53a3a TH |
7453 | static int swap_events_show(struct seq_file *m, void *v) |
7454 | { | |
aa9694bb | 7455 | struct mem_cgroup *memcg = mem_cgroup_from_seq(m); |
f3a53a3a | 7456 | |
4b82ab4f JK |
7457 | seq_printf(m, "high %lu\n", |
7458 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_HIGH])); | |
f3a53a3a TH |
7459 | seq_printf(m, "max %lu\n", |
7460 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_MAX])); | |
7461 | seq_printf(m, "fail %lu\n", | |
7462 | atomic_long_read(&memcg->memory_events[MEMCG_SWAP_FAIL])); | |
7463 | ||
7464 | return 0; | |
7465 | } | |
7466 | ||
37e84351 VD |
7467 | static struct cftype swap_files[] = { |
7468 | { | |
7469 | .name = "swap.current", | |
7470 | .flags = CFTYPE_NOT_ON_ROOT, | |
7471 | .read_u64 = swap_current_read, | |
7472 | }, | |
4b82ab4f JK |
7473 | { |
7474 | .name = "swap.high", | |
7475 | .flags = CFTYPE_NOT_ON_ROOT, | |
7476 | .seq_show = swap_high_show, | |
7477 | .write = swap_high_write, | |
7478 | }, | |
37e84351 VD |
7479 | { |
7480 | .name = "swap.max", | |
7481 | .flags = CFTYPE_NOT_ON_ROOT, | |
7482 | .seq_show = swap_max_show, | |
7483 | .write = swap_max_write, | |
7484 | }, | |
f3a53a3a TH |
7485 | { |
7486 | .name = "swap.events", | |
7487 | .flags = CFTYPE_NOT_ON_ROOT, | |
7488 | .file_offset = offsetof(struct mem_cgroup, swap_events_file), | |
7489 | .seq_show = swap_events_show, | |
7490 | }, | |
37e84351 VD |
7491 | { } /* terminate */ |
7492 | }; | |
7493 | ||
eccb52e7 | 7494 | static struct cftype memsw_files[] = { |
21afa38e JW |
7495 | { |
7496 | .name = "memsw.usage_in_bytes", | |
7497 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
7498 | .read_u64 = mem_cgroup_read_u64, | |
7499 | }, | |
7500 | { | |
7501 | .name = "memsw.max_usage_in_bytes", | |
7502 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
7503 | .write = mem_cgroup_reset, | |
7504 | .read_u64 = mem_cgroup_read_u64, | |
7505 | }, | |
7506 | { | |
7507 | .name = "memsw.limit_in_bytes", | |
7508 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
7509 | .write = mem_cgroup_write, | |
7510 | .read_u64 = mem_cgroup_read_u64, | |
7511 | }, | |
7512 | { | |
7513 | .name = "memsw.failcnt", | |
7514 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
7515 | .write = mem_cgroup_reset, | |
7516 | .read_u64 = mem_cgroup_read_u64, | |
7517 | }, | |
7518 | { }, /* terminate */ | |
7519 | }; | |
7520 | ||
f4840ccf JW |
7521 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
7522 | /** | |
7523 | * obj_cgroup_may_zswap - check if this cgroup can zswap | |
7524 | * @objcg: the object cgroup | |
7525 | * | |
7526 | * Check if the hierarchical zswap limit has been reached. | |
7527 | * | |
7528 | * This doesn't check for specific headroom, and it is not atomic | |
7529 | * either. But with zswap, the size of the allocation is only known | |
7530 | * once compression has occured, and this optimistic pre-check avoids | |
7531 | * spending cycles on compression when there is already no room left | |
7532 | * or zswap is disabled altogether somewhere in the hierarchy. | |
7533 | */ | |
7534 | bool obj_cgroup_may_zswap(struct obj_cgroup *objcg) | |
7535 | { | |
7536 | struct mem_cgroup *memcg, *original_memcg; | |
7537 | bool ret = true; | |
7538 | ||
7539 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
7540 | return true; | |
7541 | ||
7542 | original_memcg = get_mem_cgroup_from_objcg(objcg); | |
7543 | for (memcg = original_memcg; memcg != root_mem_cgroup; | |
7544 | memcg = parent_mem_cgroup(memcg)) { | |
7545 | unsigned long max = READ_ONCE(memcg->zswap_max); | |
7546 | unsigned long pages; | |
7547 | ||
7548 | if (max == PAGE_COUNTER_MAX) | |
7549 | continue; | |
7550 | if (max == 0) { | |
7551 | ret = false; | |
7552 | break; | |
7553 | } | |
7554 | ||
7555 | cgroup_rstat_flush(memcg->css.cgroup); | |
7556 | pages = memcg_page_state(memcg, MEMCG_ZSWAP_B) / PAGE_SIZE; | |
7557 | if (pages < max) | |
7558 | continue; | |
7559 | ret = false; | |
7560 | break; | |
7561 | } | |
7562 | mem_cgroup_put(original_memcg); | |
7563 | return ret; | |
7564 | } | |
7565 | ||
7566 | /** | |
7567 | * obj_cgroup_charge_zswap - charge compression backend memory | |
7568 | * @objcg: the object cgroup | |
7569 | * @size: size of compressed object | |
7570 | * | |
7571 | * This forces the charge after obj_cgroup_may_swap() allowed | |
7572 | * compression and storage in zwap for this cgroup to go ahead. | |
7573 | */ | |
7574 | void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size) | |
7575 | { | |
7576 | struct mem_cgroup *memcg; | |
7577 | ||
7578 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
7579 | return; | |
7580 | ||
7581 | VM_WARN_ON_ONCE(!(current->flags & PF_MEMALLOC)); | |
7582 | ||
7583 | /* PF_MEMALLOC context, charging must succeed */ | |
7584 | if (obj_cgroup_charge(objcg, GFP_KERNEL, size)) | |
7585 | VM_WARN_ON_ONCE(1); | |
7586 | ||
7587 | rcu_read_lock(); | |
7588 | memcg = obj_cgroup_memcg(objcg); | |
7589 | mod_memcg_state(memcg, MEMCG_ZSWAP_B, size); | |
7590 | mod_memcg_state(memcg, MEMCG_ZSWAPPED, 1); | |
7591 | rcu_read_unlock(); | |
7592 | } | |
7593 | ||
7594 | /** | |
7595 | * obj_cgroup_uncharge_zswap - uncharge compression backend memory | |
7596 | * @objcg: the object cgroup | |
7597 | * @size: size of compressed object | |
7598 | * | |
7599 | * Uncharges zswap memory on page in. | |
7600 | */ | |
7601 | void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size) | |
7602 | { | |
7603 | struct mem_cgroup *memcg; | |
7604 | ||
7605 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
7606 | return; | |
7607 | ||
7608 | obj_cgroup_uncharge(objcg, size); | |
7609 | ||
7610 | rcu_read_lock(); | |
7611 | memcg = obj_cgroup_memcg(objcg); | |
7612 | mod_memcg_state(memcg, MEMCG_ZSWAP_B, -size); | |
7613 | mod_memcg_state(memcg, MEMCG_ZSWAPPED, -1); | |
7614 | rcu_read_unlock(); | |
7615 | } | |
7616 | ||
7617 | static u64 zswap_current_read(struct cgroup_subsys_state *css, | |
7618 | struct cftype *cft) | |
7619 | { | |
7620 | cgroup_rstat_flush(css->cgroup); | |
7621 | return memcg_page_state(mem_cgroup_from_css(css), MEMCG_ZSWAP_B); | |
7622 | } | |
7623 | ||
7624 | static int zswap_max_show(struct seq_file *m, void *v) | |
7625 | { | |
7626 | return seq_puts_memcg_tunable(m, | |
7627 | READ_ONCE(mem_cgroup_from_seq(m)->zswap_max)); | |
7628 | } | |
7629 | ||
7630 | static ssize_t zswap_max_write(struct kernfs_open_file *of, | |
7631 | char *buf, size_t nbytes, loff_t off) | |
7632 | { | |
7633 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
7634 | unsigned long max; | |
7635 | int err; | |
7636 | ||
7637 | buf = strstrip(buf); | |
7638 | err = page_counter_memparse(buf, "max", &max); | |
7639 | if (err) | |
7640 | return err; | |
7641 | ||
7642 | xchg(&memcg->zswap_max, max); | |
7643 | ||
7644 | return nbytes; | |
7645 | } | |
7646 | ||
7647 | static struct cftype zswap_files[] = { | |
7648 | { | |
7649 | .name = "zswap.current", | |
7650 | .flags = CFTYPE_NOT_ON_ROOT, | |
7651 | .read_u64 = zswap_current_read, | |
7652 | }, | |
7653 | { | |
7654 | .name = "zswap.max", | |
7655 | .flags = CFTYPE_NOT_ON_ROOT, | |
7656 | .seq_show = zswap_max_show, | |
7657 | .write = zswap_max_write, | |
7658 | }, | |
7659 | { } /* terminate */ | |
7660 | }; | |
7661 | #endif /* CONFIG_MEMCG_KMEM && CONFIG_ZSWAP */ | |
7662 | ||
82ff165c BS |
7663 | /* |
7664 | * If mem_cgroup_swap_init() is implemented as a subsys_initcall() | |
7665 | * instead of a core_initcall(), this could mean cgroup_memory_noswap still | |
7666 | * remains set to false even when memcg is disabled via "cgroup_disable=memory" | |
7667 | * boot parameter. This may result in premature OOPS inside | |
7668 | * mem_cgroup_get_nr_swap_pages() function in corner cases. | |
7669 | */ | |
21afa38e JW |
7670 | static int __init mem_cgroup_swap_init(void) |
7671 | { | |
2d1c4980 JW |
7672 | /* No memory control -> no swap control */ |
7673 | if (mem_cgroup_disabled()) | |
7674 | cgroup_memory_noswap = true; | |
7675 | ||
7676 | if (cgroup_memory_noswap) | |
eccb52e7 JW |
7677 | return 0; |
7678 | ||
7679 | WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, swap_files)); | |
7680 | WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, memsw_files)); | |
f4840ccf JW |
7681 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) |
7682 | WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, zswap_files)); | |
7683 | #endif | |
21afa38e JW |
7684 | return 0; |
7685 | } | |
82ff165c | 7686 | core_initcall(mem_cgroup_swap_init); |
21afa38e JW |
7687 | |
7688 | #endif /* CONFIG_MEMCG_SWAP */ |