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8cdea7c0 BS |
1 | /* memcontrol.c - Memory Controller |
2 | * | |
3 | * Copyright IBM Corporation, 2007 | |
4 | * Author Balbir Singh <balbir@linux.vnet.ibm.com> | |
5 | * | |
78fb7466 PE |
6 | * Copyright 2007 OpenVZ SWsoft Inc |
7 | * Author: Pavel Emelianov <xemul@openvz.org> | |
8 | * | |
2e72b634 KS |
9 | * Memory thresholds |
10 | * Copyright (C) 2009 Nokia Corporation | |
11 | * Author: Kirill A. Shutemov | |
12 | * | |
7ae1e1d0 GC |
13 | * Kernel Memory Controller |
14 | * Copyright (C) 2012 Parallels Inc. and Google Inc. | |
15 | * Authors: Glauber Costa and Suleiman Souhlal | |
16 | * | |
1575e68b JW |
17 | * Native page reclaim |
18 | * Charge lifetime sanitation | |
19 | * Lockless page tracking & accounting | |
20 | * Unified hierarchy configuration model | |
21 | * Copyright (C) 2015 Red Hat, Inc., Johannes Weiner | |
22 | * | |
8cdea7c0 BS |
23 | * This program is free software; you can redistribute it and/or modify |
24 | * it under the terms of the GNU General Public License as published by | |
25 | * the Free Software Foundation; either version 2 of the License, or | |
26 | * (at your option) any later version. | |
27 | * | |
28 | * This program is distributed in the hope that it will be useful, | |
29 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
30 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
31 | * GNU General Public License for more details. | |
32 | */ | |
33 | ||
3e32cb2e | 34 | #include <linux/page_counter.h> |
8cdea7c0 BS |
35 | #include <linux/memcontrol.h> |
36 | #include <linux/cgroup.h> | |
78fb7466 | 37 | #include <linux/mm.h> |
6e84f315 | 38 | #include <linux/sched/mm.h> |
3a4f8a0b | 39 | #include <linux/shmem_fs.h> |
4ffef5fe | 40 | #include <linux/hugetlb.h> |
d13d1443 | 41 | #include <linux/pagemap.h> |
d52aa412 | 42 | #include <linux/smp.h> |
8a9f3ccd | 43 | #include <linux/page-flags.h> |
66e1707b | 44 | #include <linux/backing-dev.h> |
8a9f3ccd BS |
45 | #include <linux/bit_spinlock.h> |
46 | #include <linux/rcupdate.h> | |
e222432b | 47 | #include <linux/limits.h> |
b9e15baf | 48 | #include <linux/export.h> |
8c7c6e34 | 49 | #include <linux/mutex.h> |
bb4cc1a8 | 50 | #include <linux/rbtree.h> |
b6ac57d5 | 51 | #include <linux/slab.h> |
66e1707b | 52 | #include <linux/swap.h> |
02491447 | 53 | #include <linux/swapops.h> |
66e1707b | 54 | #include <linux/spinlock.h> |
2e72b634 | 55 | #include <linux/eventfd.h> |
79bd9814 | 56 | #include <linux/poll.h> |
2e72b634 | 57 | #include <linux/sort.h> |
66e1707b | 58 | #include <linux/fs.h> |
d2ceb9b7 | 59 | #include <linux/seq_file.h> |
70ddf637 | 60 | #include <linux/vmpressure.h> |
b69408e8 | 61 | #include <linux/mm_inline.h> |
5d1ea48b | 62 | #include <linux/swap_cgroup.h> |
cdec2e42 | 63 | #include <linux/cpu.h> |
158e0a2d | 64 | #include <linux/oom.h> |
0056f4e6 | 65 | #include <linux/lockdep.h> |
79bd9814 | 66 | #include <linux/file.h> |
b23afb93 | 67 | #include <linux/tracehook.h> |
08e552c6 | 68 | #include "internal.h" |
d1a4c0b3 | 69 | #include <net/sock.h> |
4bd2c1ee | 70 | #include <net/ip.h> |
f35c3a8e | 71 | #include "slab.h" |
8cdea7c0 | 72 | |
7c0f6ba6 | 73 | #include <linux/uaccess.h> |
8697d331 | 74 | |
cc8e970c KM |
75 | #include <trace/events/vmscan.h> |
76 | ||
073219e9 TH |
77 | struct cgroup_subsys memory_cgrp_subsys __read_mostly; |
78 | EXPORT_SYMBOL(memory_cgrp_subsys); | |
68ae564b | 79 | |
7d828602 JW |
80 | struct mem_cgroup *root_mem_cgroup __read_mostly; |
81 | ||
a181b0e8 | 82 | #define MEM_CGROUP_RECLAIM_RETRIES 5 |
8cdea7c0 | 83 | |
f7e1cb6e JW |
84 | /* Socket memory accounting disabled? */ |
85 | static bool cgroup_memory_nosocket; | |
86 | ||
04823c83 VD |
87 | /* Kernel memory accounting disabled? */ |
88 | static bool cgroup_memory_nokmem; | |
89 | ||
21afa38e | 90 | /* Whether the swap controller is active */ |
c255a458 | 91 | #ifdef CONFIG_MEMCG_SWAP |
c077719b | 92 | int do_swap_account __read_mostly; |
c077719b | 93 | #else |
a0db00fc | 94 | #define do_swap_account 0 |
c077719b KH |
95 | #endif |
96 | ||
7941d214 JW |
97 | /* Whether legacy memory+swap accounting is active */ |
98 | static bool do_memsw_account(void) | |
99 | { | |
100 | return !cgroup_subsys_on_dfl(memory_cgrp_subsys) && do_swap_account; | |
101 | } | |
102 | ||
71cd3113 | 103 | static const char *const mem_cgroup_lru_names[] = { |
58cf188e SZ |
104 | "inactive_anon", |
105 | "active_anon", | |
106 | "inactive_file", | |
107 | "active_file", | |
108 | "unevictable", | |
109 | }; | |
110 | ||
a0db00fc KS |
111 | #define THRESHOLDS_EVENTS_TARGET 128 |
112 | #define SOFTLIMIT_EVENTS_TARGET 1024 | |
113 | #define NUMAINFO_EVENTS_TARGET 1024 | |
e9f8974f | 114 | |
bb4cc1a8 AM |
115 | /* |
116 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
117 | * their hierarchy representation | |
118 | */ | |
119 | ||
ef8f2327 | 120 | struct mem_cgroup_tree_per_node { |
bb4cc1a8 AM |
121 | struct rb_root rb_root; |
122 | spinlock_t lock; | |
123 | }; | |
124 | ||
bb4cc1a8 AM |
125 | struct mem_cgroup_tree { |
126 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
127 | }; | |
128 | ||
129 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
130 | ||
9490ff27 KH |
131 | /* for OOM */ |
132 | struct mem_cgroup_eventfd_list { | |
133 | struct list_head list; | |
134 | struct eventfd_ctx *eventfd; | |
135 | }; | |
2e72b634 | 136 | |
79bd9814 TH |
137 | /* |
138 | * cgroup_event represents events which userspace want to receive. | |
139 | */ | |
3bc942f3 | 140 | struct mem_cgroup_event { |
79bd9814 | 141 | /* |
59b6f873 | 142 | * memcg which the event belongs to. |
79bd9814 | 143 | */ |
59b6f873 | 144 | struct mem_cgroup *memcg; |
79bd9814 TH |
145 | /* |
146 | * eventfd to signal userspace about the event. | |
147 | */ | |
148 | struct eventfd_ctx *eventfd; | |
149 | /* | |
150 | * Each of these stored in a list by the cgroup. | |
151 | */ | |
152 | struct list_head list; | |
fba94807 TH |
153 | /* |
154 | * register_event() callback will be used to add new userspace | |
155 | * waiter for changes related to this event. Use eventfd_signal() | |
156 | * on eventfd to send notification to userspace. | |
157 | */ | |
59b6f873 | 158 | int (*register_event)(struct mem_cgroup *memcg, |
347c4a87 | 159 | struct eventfd_ctx *eventfd, const char *args); |
fba94807 TH |
160 | /* |
161 | * unregister_event() callback will be called when userspace closes | |
162 | * the eventfd or on cgroup removing. This callback must be set, | |
163 | * if you want provide notification functionality. | |
164 | */ | |
59b6f873 | 165 | void (*unregister_event)(struct mem_cgroup *memcg, |
fba94807 | 166 | struct eventfd_ctx *eventfd); |
79bd9814 TH |
167 | /* |
168 | * All fields below needed to unregister event when | |
169 | * userspace closes eventfd. | |
170 | */ | |
171 | poll_table pt; | |
172 | wait_queue_head_t *wqh; | |
ac6424b9 | 173 | wait_queue_entry_t wait; |
79bd9814 TH |
174 | struct work_struct remove; |
175 | }; | |
176 | ||
c0ff4b85 R |
177 | static void mem_cgroup_threshold(struct mem_cgroup *memcg); |
178 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); | |
2e72b634 | 179 | |
7dc74be0 DN |
180 | /* Stuffs for move charges at task migration. */ |
181 | /* | |
1dfab5ab | 182 | * Types of charges to be moved. |
7dc74be0 | 183 | */ |
1dfab5ab JW |
184 | #define MOVE_ANON 0x1U |
185 | #define MOVE_FILE 0x2U | |
186 | #define MOVE_MASK (MOVE_ANON | MOVE_FILE) | |
7dc74be0 | 187 | |
4ffef5fe DN |
188 | /* "mc" and its members are protected by cgroup_mutex */ |
189 | static struct move_charge_struct { | |
b1dd693e | 190 | spinlock_t lock; /* for from, to */ |
264a0ae1 | 191 | struct mm_struct *mm; |
4ffef5fe DN |
192 | struct mem_cgroup *from; |
193 | struct mem_cgroup *to; | |
1dfab5ab | 194 | unsigned long flags; |
4ffef5fe | 195 | unsigned long precharge; |
854ffa8d | 196 | unsigned long moved_charge; |
483c30b5 | 197 | unsigned long moved_swap; |
8033b97c DN |
198 | struct task_struct *moving_task; /* a task moving charges */ |
199 | wait_queue_head_t waitq; /* a waitq for other context */ | |
200 | } mc = { | |
2bd9bb20 | 201 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
202 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
203 | }; | |
4ffef5fe | 204 | |
4e416953 BS |
205 | /* |
206 | * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft | |
207 | * limit reclaim to prevent infinite loops, if they ever occur. | |
208 | */ | |
a0db00fc | 209 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS 100 |
bb4cc1a8 | 210 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS 2 |
4e416953 | 211 | |
217bc319 KH |
212 | enum charge_type { |
213 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, | |
41326c17 | 214 | MEM_CGROUP_CHARGE_TYPE_ANON, |
d13d1443 | 215 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
8a9478ca | 216 | MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ |
c05555b5 KH |
217 | NR_CHARGE_TYPE, |
218 | }; | |
219 | ||
8c7c6e34 | 220 | /* for encoding cft->private value on file */ |
86ae53e1 GC |
221 | enum res_type { |
222 | _MEM, | |
223 | _MEMSWAP, | |
224 | _OOM_TYPE, | |
510fc4e1 | 225 | _KMEM, |
d55f90bf | 226 | _TCP, |
86ae53e1 GC |
227 | }; |
228 | ||
a0db00fc KS |
229 | #define MEMFILE_PRIVATE(x, val) ((x) << 16 | (val)) |
230 | #define MEMFILE_TYPE(val) ((val) >> 16 & 0xffff) | |
8c7c6e34 | 231 | #define MEMFILE_ATTR(val) ((val) & 0xffff) |
9490ff27 KH |
232 | /* Used for OOM nofiier */ |
233 | #define OOM_CONTROL (0) | |
8c7c6e34 | 234 | |
70ddf637 AV |
235 | /* Some nice accessors for the vmpressure. */ |
236 | struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg) | |
237 | { | |
238 | if (!memcg) | |
239 | memcg = root_mem_cgroup; | |
240 | return &memcg->vmpressure; | |
241 | } | |
242 | ||
243 | struct cgroup_subsys_state *vmpressure_to_css(struct vmpressure *vmpr) | |
244 | { | |
245 | return &container_of(vmpr, struct mem_cgroup, vmpressure)->css; | |
246 | } | |
247 | ||
7ffc0edc MH |
248 | static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) |
249 | { | |
250 | return (memcg == root_mem_cgroup); | |
251 | } | |
252 | ||
127424c8 | 253 | #ifndef CONFIG_SLOB |
55007d84 | 254 | /* |
f7ce3190 | 255 | * This will be the memcg's index in each cache's ->memcg_params.memcg_caches. |
b8627835 LZ |
256 | * The main reason for not using cgroup id for this: |
257 | * this works better in sparse environments, where we have a lot of memcgs, | |
258 | * but only a few kmem-limited. Or also, if we have, for instance, 200 | |
259 | * memcgs, and none but the 200th is kmem-limited, we'd have to have a | |
260 | * 200 entry array for that. | |
55007d84 | 261 | * |
dbcf73e2 VD |
262 | * The current size of the caches array is stored in memcg_nr_cache_ids. It |
263 | * will double each time we have to increase it. | |
55007d84 | 264 | */ |
dbcf73e2 VD |
265 | static DEFINE_IDA(memcg_cache_ida); |
266 | int memcg_nr_cache_ids; | |
749c5415 | 267 | |
05257a1a VD |
268 | /* Protects memcg_nr_cache_ids */ |
269 | static DECLARE_RWSEM(memcg_cache_ids_sem); | |
270 | ||
271 | void memcg_get_cache_ids(void) | |
272 | { | |
273 | down_read(&memcg_cache_ids_sem); | |
274 | } | |
275 | ||
276 | void memcg_put_cache_ids(void) | |
277 | { | |
278 | up_read(&memcg_cache_ids_sem); | |
279 | } | |
280 | ||
55007d84 GC |
281 | /* |
282 | * MIN_SIZE is different than 1, because we would like to avoid going through | |
283 | * the alloc/free process all the time. In a small machine, 4 kmem-limited | |
284 | * cgroups is a reasonable guess. In the future, it could be a parameter or | |
285 | * tunable, but that is strictly not necessary. | |
286 | * | |
b8627835 | 287 | * MAX_SIZE should be as large as the number of cgrp_ids. Ideally, we could get |
55007d84 GC |
288 | * this constant directly from cgroup, but it is understandable that this is |
289 | * better kept as an internal representation in cgroup.c. In any case, the | |
b8627835 | 290 | * cgrp_id space is not getting any smaller, and we don't have to necessarily |
55007d84 GC |
291 | * increase ours as well if it increases. |
292 | */ | |
293 | #define MEMCG_CACHES_MIN_SIZE 4 | |
b8627835 | 294 | #define MEMCG_CACHES_MAX_SIZE MEM_CGROUP_ID_MAX |
55007d84 | 295 | |
d7f25f8a GC |
296 | /* |
297 | * A lot of the calls to the cache allocation functions are expected to be | |
298 | * inlined by the compiler. Since the calls to memcg_kmem_get_cache are | |
299 | * conditional to this static branch, we'll have to allow modules that does | |
300 | * kmem_cache_alloc and the such to see this symbol as well | |
301 | */ | |
ef12947c | 302 | DEFINE_STATIC_KEY_FALSE(memcg_kmem_enabled_key); |
d7f25f8a | 303 | EXPORT_SYMBOL(memcg_kmem_enabled_key); |
a8964b9b | 304 | |
17cc4dfe TH |
305 | struct workqueue_struct *memcg_kmem_cache_wq; |
306 | ||
127424c8 | 307 | #endif /* !CONFIG_SLOB */ |
a8964b9b | 308 | |
ad7fa852 TH |
309 | /** |
310 | * mem_cgroup_css_from_page - css of the memcg associated with a page | |
311 | * @page: page of interest | |
312 | * | |
313 | * If memcg is bound to the default hierarchy, css of the memcg associated | |
314 | * with @page is returned. The returned css remains associated with @page | |
315 | * until it is released. | |
316 | * | |
317 | * If memcg is bound to a traditional hierarchy, the css of root_mem_cgroup | |
318 | * is returned. | |
ad7fa852 TH |
319 | */ |
320 | struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page) | |
321 | { | |
322 | struct mem_cgroup *memcg; | |
323 | ||
ad7fa852 TH |
324 | memcg = page->mem_cgroup; |
325 | ||
9e10a130 | 326 | if (!memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
ad7fa852 TH |
327 | memcg = root_mem_cgroup; |
328 | ||
ad7fa852 TH |
329 | return &memcg->css; |
330 | } | |
331 | ||
2fc04524 VD |
332 | /** |
333 | * page_cgroup_ino - return inode number of the memcg a page is charged to | |
334 | * @page: the page | |
335 | * | |
336 | * Look up the closest online ancestor of the memory cgroup @page is charged to | |
337 | * and return its inode number or 0 if @page is not charged to any cgroup. It | |
338 | * is safe to call this function without holding a reference to @page. | |
339 | * | |
340 | * Note, this function is inherently racy, because there is nothing to prevent | |
341 | * the cgroup inode from getting torn down and potentially reallocated a moment | |
342 | * after page_cgroup_ino() returns, so it only should be used by callers that | |
343 | * do not care (such as procfs interfaces). | |
344 | */ | |
345 | ino_t page_cgroup_ino(struct page *page) | |
346 | { | |
347 | struct mem_cgroup *memcg; | |
348 | unsigned long ino = 0; | |
349 | ||
350 | rcu_read_lock(); | |
351 | memcg = READ_ONCE(page->mem_cgroup); | |
352 | while (memcg && !(memcg->css.flags & CSS_ONLINE)) | |
353 | memcg = parent_mem_cgroup(memcg); | |
354 | if (memcg) | |
355 | ino = cgroup_ino(memcg->css.cgroup); | |
356 | rcu_read_unlock(); | |
357 | return ino; | |
358 | } | |
359 | ||
ef8f2327 MG |
360 | static struct mem_cgroup_per_node * |
361 | mem_cgroup_page_nodeinfo(struct mem_cgroup *memcg, struct page *page) | |
f64c3f54 | 362 | { |
97a6c37b | 363 | int nid = page_to_nid(page); |
f64c3f54 | 364 | |
ef8f2327 | 365 | return memcg->nodeinfo[nid]; |
f64c3f54 BS |
366 | } |
367 | ||
ef8f2327 MG |
368 | static struct mem_cgroup_tree_per_node * |
369 | soft_limit_tree_node(int nid) | |
bb4cc1a8 | 370 | { |
ef8f2327 | 371 | return soft_limit_tree.rb_tree_per_node[nid]; |
bb4cc1a8 AM |
372 | } |
373 | ||
ef8f2327 | 374 | static struct mem_cgroup_tree_per_node * |
bb4cc1a8 AM |
375 | soft_limit_tree_from_page(struct page *page) |
376 | { | |
377 | int nid = page_to_nid(page); | |
bb4cc1a8 | 378 | |
ef8f2327 | 379 | return soft_limit_tree.rb_tree_per_node[nid]; |
bb4cc1a8 AM |
380 | } |
381 | ||
ef8f2327 MG |
382 | static void __mem_cgroup_insert_exceeded(struct mem_cgroup_per_node *mz, |
383 | struct mem_cgroup_tree_per_node *mctz, | |
3e32cb2e | 384 | unsigned long new_usage_in_excess) |
bb4cc1a8 AM |
385 | { |
386 | struct rb_node **p = &mctz->rb_root.rb_node; | |
387 | struct rb_node *parent = NULL; | |
ef8f2327 | 388 | struct mem_cgroup_per_node *mz_node; |
bb4cc1a8 AM |
389 | |
390 | if (mz->on_tree) | |
391 | return; | |
392 | ||
393 | mz->usage_in_excess = new_usage_in_excess; | |
394 | if (!mz->usage_in_excess) | |
395 | return; | |
396 | while (*p) { | |
397 | parent = *p; | |
ef8f2327 | 398 | mz_node = rb_entry(parent, struct mem_cgroup_per_node, |
bb4cc1a8 AM |
399 | tree_node); |
400 | if (mz->usage_in_excess < mz_node->usage_in_excess) | |
401 | p = &(*p)->rb_left; | |
402 | /* | |
403 | * We can't avoid mem cgroups that are over their soft | |
404 | * limit by the same amount | |
405 | */ | |
406 | else if (mz->usage_in_excess >= mz_node->usage_in_excess) | |
407 | p = &(*p)->rb_right; | |
408 | } | |
409 | rb_link_node(&mz->tree_node, parent, p); | |
410 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
411 | mz->on_tree = true; | |
412 | } | |
413 | ||
ef8f2327 MG |
414 | static void __mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz, |
415 | struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 AM |
416 | { |
417 | if (!mz->on_tree) | |
418 | return; | |
419 | rb_erase(&mz->tree_node, &mctz->rb_root); | |
420 | mz->on_tree = false; | |
421 | } | |
422 | ||
ef8f2327 MG |
423 | static void mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz, |
424 | struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 425 | { |
0a31bc97 JW |
426 | unsigned long flags; |
427 | ||
428 | spin_lock_irqsave(&mctz->lock, flags); | |
cf2c8127 | 429 | __mem_cgroup_remove_exceeded(mz, mctz); |
0a31bc97 | 430 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
431 | } |
432 | ||
3e32cb2e JW |
433 | static unsigned long soft_limit_excess(struct mem_cgroup *memcg) |
434 | { | |
435 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
4db0c3c2 | 436 | unsigned long soft_limit = READ_ONCE(memcg->soft_limit); |
3e32cb2e JW |
437 | unsigned long excess = 0; |
438 | ||
439 | if (nr_pages > soft_limit) | |
440 | excess = nr_pages - soft_limit; | |
441 | ||
442 | return excess; | |
443 | } | |
bb4cc1a8 AM |
444 | |
445 | static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page) | |
446 | { | |
3e32cb2e | 447 | unsigned long excess; |
ef8f2327 MG |
448 | struct mem_cgroup_per_node *mz; |
449 | struct mem_cgroup_tree_per_node *mctz; | |
bb4cc1a8 | 450 | |
e231875b | 451 | mctz = soft_limit_tree_from_page(page); |
bfc7228b LD |
452 | if (!mctz) |
453 | return; | |
bb4cc1a8 AM |
454 | /* |
455 | * Necessary to update all ancestors when hierarchy is used. | |
456 | * because their event counter is not touched. | |
457 | */ | |
458 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
ef8f2327 | 459 | mz = mem_cgroup_page_nodeinfo(memcg, page); |
3e32cb2e | 460 | excess = soft_limit_excess(memcg); |
bb4cc1a8 AM |
461 | /* |
462 | * We have to update the tree if mz is on RB-tree or | |
463 | * mem is over its softlimit. | |
464 | */ | |
465 | if (excess || mz->on_tree) { | |
0a31bc97 JW |
466 | unsigned long flags; |
467 | ||
468 | spin_lock_irqsave(&mctz->lock, flags); | |
bb4cc1a8 AM |
469 | /* if on-tree, remove it */ |
470 | if (mz->on_tree) | |
cf2c8127 | 471 | __mem_cgroup_remove_exceeded(mz, mctz); |
bb4cc1a8 AM |
472 | /* |
473 | * Insert again. mz->usage_in_excess will be updated. | |
474 | * If excess is 0, no tree ops. | |
475 | */ | |
cf2c8127 | 476 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 477 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
478 | } |
479 | } | |
480 | } | |
481 | ||
482 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) | |
483 | { | |
ef8f2327 MG |
484 | struct mem_cgroup_tree_per_node *mctz; |
485 | struct mem_cgroup_per_node *mz; | |
486 | int nid; | |
bb4cc1a8 | 487 | |
e231875b | 488 | for_each_node(nid) { |
ef8f2327 MG |
489 | mz = mem_cgroup_nodeinfo(memcg, nid); |
490 | mctz = soft_limit_tree_node(nid); | |
bfc7228b LD |
491 | if (mctz) |
492 | mem_cgroup_remove_exceeded(mz, mctz); | |
bb4cc1a8 AM |
493 | } |
494 | } | |
495 | ||
ef8f2327 MG |
496 | static struct mem_cgroup_per_node * |
497 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 AM |
498 | { |
499 | struct rb_node *rightmost = NULL; | |
ef8f2327 | 500 | struct mem_cgroup_per_node *mz; |
bb4cc1a8 AM |
501 | |
502 | retry: | |
503 | mz = NULL; | |
504 | rightmost = rb_last(&mctz->rb_root); | |
505 | if (!rightmost) | |
506 | goto done; /* Nothing to reclaim from */ | |
507 | ||
ef8f2327 | 508 | mz = rb_entry(rightmost, struct mem_cgroup_per_node, tree_node); |
bb4cc1a8 AM |
509 | /* |
510 | * Remove the node now but someone else can add it back, | |
511 | * we will to add it back at the end of reclaim to its correct | |
512 | * position in the tree. | |
513 | */ | |
cf2c8127 | 514 | __mem_cgroup_remove_exceeded(mz, mctz); |
3e32cb2e | 515 | if (!soft_limit_excess(mz->memcg) || |
ec903c0c | 516 | !css_tryget_online(&mz->memcg->css)) |
bb4cc1a8 AM |
517 | goto retry; |
518 | done: | |
519 | return mz; | |
520 | } | |
521 | ||
ef8f2327 MG |
522 | static struct mem_cgroup_per_node * |
523 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz) | |
bb4cc1a8 | 524 | { |
ef8f2327 | 525 | struct mem_cgroup_per_node *mz; |
bb4cc1a8 | 526 | |
0a31bc97 | 527 | spin_lock_irq(&mctz->lock); |
bb4cc1a8 | 528 | mz = __mem_cgroup_largest_soft_limit_node(mctz); |
0a31bc97 | 529 | spin_unlock_irq(&mctz->lock); |
bb4cc1a8 AM |
530 | return mz; |
531 | } | |
532 | ||
711d3d2c | 533 | /* |
484ebb3b GT |
534 | * Return page count for single (non recursive) @memcg. |
535 | * | |
711d3d2c KH |
536 | * Implementation Note: reading percpu statistics for memcg. |
537 | * | |
538 | * Both of vmstat[] and percpu_counter has threshold and do periodic | |
539 | * synchronization to implement "quick" read. There are trade-off between | |
540 | * reading cost and precision of value. Then, we may have a chance to implement | |
484ebb3b | 541 | * a periodic synchronization of counter in memcg's counter. |
711d3d2c KH |
542 | * |
543 | * But this _read() function is used for user interface now. The user accounts | |
544 | * memory usage by memory cgroup and he _always_ requires exact value because | |
545 | * he accounts memory. Even if we provide quick-and-fuzzy read, we always | |
546 | * have to visit all online cpus and make sum. So, for now, unnecessary | |
547 | * synchronization is not implemented. (just implemented for cpu hotplug) | |
548 | * | |
549 | * If there are kernel internal actions which can make use of some not-exact | |
550 | * value, and reading all cpu value can be performance bottleneck in some | |
484ebb3b | 551 | * common workload, threshold and synchronization as vmstat[] should be |
711d3d2c KH |
552 | * implemented. |
553 | */ | |
c62b1a3b | 554 | |
ccda7f43 JW |
555 | static unsigned long memcg_sum_events(struct mem_cgroup *memcg, |
556 | enum memcg_event_item event) | |
e9f8974f JW |
557 | { |
558 | unsigned long val = 0; | |
559 | int cpu; | |
560 | ||
733a572e | 561 | for_each_possible_cpu(cpu) |
df0e53d0 | 562 | val += per_cpu(memcg->stat->events[event], cpu); |
e9f8974f JW |
563 | return val; |
564 | } | |
565 | ||
c0ff4b85 | 566 | static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, |
b070e65c | 567 | struct page *page, |
f627c2f5 | 568 | bool compound, int nr_pages) |
d52aa412 | 569 | { |
b2402857 KH |
570 | /* |
571 | * Here, RSS means 'mapped anon' and anon's SwapCache. Shmem/tmpfs is | |
572 | * counted as CACHE even if it's on ANON LRU. | |
573 | */ | |
0a31bc97 | 574 | if (PageAnon(page)) |
71cd3113 | 575 | __this_cpu_add(memcg->stat->count[MEMCG_RSS], nr_pages); |
9a4caf1e | 576 | else { |
71cd3113 | 577 | __this_cpu_add(memcg->stat->count[MEMCG_CACHE], nr_pages); |
9a4caf1e | 578 | if (PageSwapBacked(page)) |
71cd3113 | 579 | __this_cpu_add(memcg->stat->count[NR_SHMEM], nr_pages); |
9a4caf1e | 580 | } |
55e462b0 | 581 | |
f627c2f5 KS |
582 | if (compound) { |
583 | VM_BUG_ON_PAGE(!PageTransHuge(page), page); | |
71cd3113 | 584 | __this_cpu_add(memcg->stat->count[MEMCG_RSS_HUGE], nr_pages); |
f627c2f5 | 585 | } |
b070e65c | 586 | |
e401f176 KH |
587 | /* pagein of a big page is an event. So, ignore page size */ |
588 | if (nr_pages > 0) | |
df0e53d0 | 589 | __this_cpu_inc(memcg->stat->events[PGPGIN]); |
3751d604 | 590 | else { |
df0e53d0 | 591 | __this_cpu_inc(memcg->stat->events[PGPGOUT]); |
3751d604 KH |
592 | nr_pages = -nr_pages; /* for event */ |
593 | } | |
e401f176 | 594 | |
13114716 | 595 | __this_cpu_add(memcg->stat->nr_page_events, nr_pages); |
6d12e2d8 KH |
596 | } |
597 | ||
0a6b76dd VD |
598 | unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, |
599 | int nid, unsigned int lru_mask) | |
bb2a0de9 | 600 | { |
b4536f0c | 601 | struct lruvec *lruvec = mem_cgroup_lruvec(NODE_DATA(nid), memcg); |
e231875b | 602 | unsigned long nr = 0; |
ef8f2327 | 603 | enum lru_list lru; |
889976db | 604 | |
e231875b | 605 | VM_BUG_ON((unsigned)nid >= nr_node_ids); |
bb2a0de9 | 606 | |
ef8f2327 MG |
607 | for_each_lru(lru) { |
608 | if (!(BIT(lru) & lru_mask)) | |
609 | continue; | |
b4536f0c | 610 | nr += mem_cgroup_get_lru_size(lruvec, lru); |
e231875b JZ |
611 | } |
612 | return nr; | |
889976db | 613 | } |
bb2a0de9 | 614 | |
c0ff4b85 | 615 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, |
bb2a0de9 | 616 | unsigned int lru_mask) |
6d12e2d8 | 617 | { |
e231875b | 618 | unsigned long nr = 0; |
889976db | 619 | int nid; |
6d12e2d8 | 620 | |
31aaea4a | 621 | for_each_node_state(nid, N_MEMORY) |
e231875b JZ |
622 | nr += mem_cgroup_node_nr_lru_pages(memcg, nid, lru_mask); |
623 | return nr; | |
d52aa412 KH |
624 | } |
625 | ||
f53d7ce3 JW |
626 | static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg, |
627 | enum mem_cgroup_events_target target) | |
7a159cc9 JW |
628 | { |
629 | unsigned long val, next; | |
630 | ||
13114716 | 631 | val = __this_cpu_read(memcg->stat->nr_page_events); |
4799401f | 632 | next = __this_cpu_read(memcg->stat->targets[target]); |
7a159cc9 | 633 | /* from time_after() in jiffies.h */ |
6a1a8b80 | 634 | if ((long)(next - val) < 0) { |
f53d7ce3 JW |
635 | switch (target) { |
636 | case MEM_CGROUP_TARGET_THRESH: | |
637 | next = val + THRESHOLDS_EVENTS_TARGET; | |
638 | break; | |
bb4cc1a8 AM |
639 | case MEM_CGROUP_TARGET_SOFTLIMIT: |
640 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
641 | break; | |
f53d7ce3 JW |
642 | case MEM_CGROUP_TARGET_NUMAINFO: |
643 | next = val + NUMAINFO_EVENTS_TARGET; | |
644 | break; | |
645 | default: | |
646 | break; | |
647 | } | |
648 | __this_cpu_write(memcg->stat->targets[target], next); | |
649 | return true; | |
7a159cc9 | 650 | } |
f53d7ce3 | 651 | return false; |
d2265e6f KH |
652 | } |
653 | ||
654 | /* | |
655 | * Check events in order. | |
656 | * | |
657 | */ | |
c0ff4b85 | 658 | static void memcg_check_events(struct mem_cgroup *memcg, struct page *page) |
d2265e6f KH |
659 | { |
660 | /* threshold event is triggered in finer grain than soft limit */ | |
f53d7ce3 JW |
661 | if (unlikely(mem_cgroup_event_ratelimit(memcg, |
662 | MEM_CGROUP_TARGET_THRESH))) { | |
bb4cc1a8 | 663 | bool do_softlimit; |
82b3f2a7 | 664 | bool do_numainfo __maybe_unused; |
f53d7ce3 | 665 | |
bb4cc1a8 AM |
666 | do_softlimit = mem_cgroup_event_ratelimit(memcg, |
667 | MEM_CGROUP_TARGET_SOFTLIMIT); | |
f53d7ce3 JW |
668 | #if MAX_NUMNODES > 1 |
669 | do_numainfo = mem_cgroup_event_ratelimit(memcg, | |
670 | MEM_CGROUP_TARGET_NUMAINFO); | |
671 | #endif | |
c0ff4b85 | 672 | mem_cgroup_threshold(memcg); |
bb4cc1a8 AM |
673 | if (unlikely(do_softlimit)) |
674 | mem_cgroup_update_tree(memcg, page); | |
453a9bf3 | 675 | #if MAX_NUMNODES > 1 |
f53d7ce3 | 676 | if (unlikely(do_numainfo)) |
c0ff4b85 | 677 | atomic_inc(&memcg->numainfo_events); |
453a9bf3 | 678 | #endif |
0a31bc97 | 679 | } |
d2265e6f KH |
680 | } |
681 | ||
cf475ad2 | 682 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 683 | { |
31a78f23 BS |
684 | /* |
685 | * mm_update_next_owner() may clear mm->owner to NULL | |
686 | * if it races with swapoff, page migration, etc. | |
687 | * So this can be called with p == NULL. | |
688 | */ | |
689 | if (unlikely(!p)) | |
690 | return NULL; | |
691 | ||
073219e9 | 692 | return mem_cgroup_from_css(task_css(p, memory_cgrp_id)); |
78fb7466 | 693 | } |
33398cf2 | 694 | EXPORT_SYMBOL(mem_cgroup_from_task); |
78fb7466 | 695 | |
df381975 | 696 | static struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm) |
54595fe2 | 697 | { |
c0ff4b85 | 698 | struct mem_cgroup *memcg = NULL; |
0b7f569e | 699 | |
54595fe2 KH |
700 | rcu_read_lock(); |
701 | do { | |
6f6acb00 MH |
702 | /* |
703 | * Page cache insertions can happen withou an | |
704 | * actual mm context, e.g. during disk probing | |
705 | * on boot, loopback IO, acct() writes etc. | |
706 | */ | |
707 | if (unlikely(!mm)) | |
df381975 | 708 | memcg = root_mem_cgroup; |
6f6acb00 MH |
709 | else { |
710 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
711 | if (unlikely(!memcg)) | |
712 | memcg = root_mem_cgroup; | |
713 | } | |
ec903c0c | 714 | } while (!css_tryget_online(&memcg->css)); |
54595fe2 | 715 | rcu_read_unlock(); |
c0ff4b85 | 716 | return memcg; |
54595fe2 KH |
717 | } |
718 | ||
5660048c JW |
719 | /** |
720 | * mem_cgroup_iter - iterate over memory cgroup hierarchy | |
721 | * @root: hierarchy root | |
722 | * @prev: previously returned memcg, NULL on first invocation | |
723 | * @reclaim: cookie for shared reclaim walks, NULL for full walks | |
724 | * | |
725 | * Returns references to children of the hierarchy below @root, or | |
726 | * @root itself, or %NULL after a full round-trip. | |
727 | * | |
728 | * Caller must pass the return value in @prev on subsequent | |
729 | * invocations for reference counting, or use mem_cgroup_iter_break() | |
730 | * to cancel a hierarchy walk before the round-trip is complete. | |
731 | * | |
732 | * Reclaimers can specify a zone and a priority level in @reclaim to | |
733 | * divide up the memcgs in the hierarchy among all concurrent | |
734 | * reclaimers operating on the same zone and priority. | |
735 | */ | |
694fbc0f | 736 | struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, |
5660048c | 737 | struct mem_cgroup *prev, |
694fbc0f | 738 | struct mem_cgroup_reclaim_cookie *reclaim) |
14067bb3 | 739 | { |
33398cf2 | 740 | struct mem_cgroup_reclaim_iter *uninitialized_var(iter); |
5ac8fb31 | 741 | struct cgroup_subsys_state *css = NULL; |
9f3a0d09 | 742 | struct mem_cgroup *memcg = NULL; |
5ac8fb31 | 743 | struct mem_cgroup *pos = NULL; |
711d3d2c | 744 | |
694fbc0f AM |
745 | if (mem_cgroup_disabled()) |
746 | return NULL; | |
5660048c | 747 | |
9f3a0d09 JW |
748 | if (!root) |
749 | root = root_mem_cgroup; | |
7d74b06f | 750 | |
9f3a0d09 | 751 | if (prev && !reclaim) |
5ac8fb31 | 752 | pos = prev; |
14067bb3 | 753 | |
9f3a0d09 JW |
754 | if (!root->use_hierarchy && root != root_mem_cgroup) { |
755 | if (prev) | |
5ac8fb31 | 756 | goto out; |
694fbc0f | 757 | return root; |
9f3a0d09 | 758 | } |
14067bb3 | 759 | |
542f85f9 | 760 | rcu_read_lock(); |
5f578161 | 761 | |
5ac8fb31 | 762 | if (reclaim) { |
ef8f2327 | 763 | struct mem_cgroup_per_node *mz; |
5ac8fb31 | 764 | |
ef8f2327 | 765 | mz = mem_cgroup_nodeinfo(root, reclaim->pgdat->node_id); |
5ac8fb31 JW |
766 | iter = &mz->iter[reclaim->priority]; |
767 | ||
768 | if (prev && reclaim->generation != iter->generation) | |
769 | goto out_unlock; | |
770 | ||
6df38689 | 771 | while (1) { |
4db0c3c2 | 772 | pos = READ_ONCE(iter->position); |
6df38689 VD |
773 | if (!pos || css_tryget(&pos->css)) |
774 | break; | |
5ac8fb31 | 775 | /* |
6df38689 VD |
776 | * css reference reached zero, so iter->position will |
777 | * be cleared by ->css_released. However, we should not | |
778 | * rely on this happening soon, because ->css_released | |
779 | * is called from a work queue, and by busy-waiting we | |
780 | * might block it. So we clear iter->position right | |
781 | * away. | |
5ac8fb31 | 782 | */ |
6df38689 VD |
783 | (void)cmpxchg(&iter->position, pos, NULL); |
784 | } | |
5ac8fb31 JW |
785 | } |
786 | ||
787 | if (pos) | |
788 | css = &pos->css; | |
789 | ||
790 | for (;;) { | |
791 | css = css_next_descendant_pre(css, &root->css); | |
792 | if (!css) { | |
793 | /* | |
794 | * Reclaimers share the hierarchy walk, and a | |
795 | * new one might jump in right at the end of | |
796 | * the hierarchy - make sure they see at least | |
797 | * one group and restart from the beginning. | |
798 | */ | |
799 | if (!prev) | |
800 | continue; | |
801 | break; | |
527a5ec9 | 802 | } |
7d74b06f | 803 | |
5ac8fb31 JW |
804 | /* |
805 | * Verify the css and acquire a reference. The root | |
806 | * is provided by the caller, so we know it's alive | |
807 | * and kicking, and don't take an extra reference. | |
808 | */ | |
809 | memcg = mem_cgroup_from_css(css); | |
14067bb3 | 810 | |
5ac8fb31 JW |
811 | if (css == &root->css) |
812 | break; | |
14067bb3 | 813 | |
0b8f73e1 JW |
814 | if (css_tryget(css)) |
815 | break; | |
9f3a0d09 | 816 | |
5ac8fb31 | 817 | memcg = NULL; |
9f3a0d09 | 818 | } |
5ac8fb31 JW |
819 | |
820 | if (reclaim) { | |
5ac8fb31 | 821 | /* |
6df38689 VD |
822 | * The position could have already been updated by a competing |
823 | * thread, so check that the value hasn't changed since we read | |
824 | * it to avoid reclaiming from the same cgroup twice. | |
5ac8fb31 | 825 | */ |
6df38689 VD |
826 | (void)cmpxchg(&iter->position, pos, memcg); |
827 | ||
5ac8fb31 JW |
828 | if (pos) |
829 | css_put(&pos->css); | |
830 | ||
831 | if (!memcg) | |
832 | iter->generation++; | |
833 | else if (!prev) | |
834 | reclaim->generation = iter->generation; | |
9f3a0d09 | 835 | } |
5ac8fb31 | 836 | |
542f85f9 MH |
837 | out_unlock: |
838 | rcu_read_unlock(); | |
5ac8fb31 | 839 | out: |
c40046f3 MH |
840 | if (prev && prev != root) |
841 | css_put(&prev->css); | |
842 | ||
9f3a0d09 | 843 | return memcg; |
14067bb3 | 844 | } |
7d74b06f | 845 | |
5660048c JW |
846 | /** |
847 | * mem_cgroup_iter_break - abort a hierarchy walk prematurely | |
848 | * @root: hierarchy root | |
849 | * @prev: last visited hierarchy member as returned by mem_cgroup_iter() | |
850 | */ | |
851 | void mem_cgroup_iter_break(struct mem_cgroup *root, | |
852 | struct mem_cgroup *prev) | |
9f3a0d09 JW |
853 | { |
854 | if (!root) | |
855 | root = root_mem_cgroup; | |
856 | if (prev && prev != root) | |
857 | css_put(&prev->css); | |
858 | } | |
7d74b06f | 859 | |
6df38689 VD |
860 | static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg) |
861 | { | |
862 | struct mem_cgroup *memcg = dead_memcg; | |
863 | struct mem_cgroup_reclaim_iter *iter; | |
ef8f2327 MG |
864 | struct mem_cgroup_per_node *mz; |
865 | int nid; | |
6df38689 VD |
866 | int i; |
867 | ||
868 | while ((memcg = parent_mem_cgroup(memcg))) { | |
869 | for_each_node(nid) { | |
ef8f2327 MG |
870 | mz = mem_cgroup_nodeinfo(memcg, nid); |
871 | for (i = 0; i <= DEF_PRIORITY; i++) { | |
872 | iter = &mz->iter[i]; | |
873 | cmpxchg(&iter->position, | |
874 | dead_memcg, NULL); | |
6df38689 VD |
875 | } |
876 | } | |
877 | } | |
878 | } | |
879 | ||
9f3a0d09 JW |
880 | /* |
881 | * Iteration constructs for visiting all cgroups (under a tree). If | |
882 | * loops are exited prematurely (break), mem_cgroup_iter_break() must | |
883 | * be used for reference counting. | |
884 | */ | |
885 | #define for_each_mem_cgroup_tree(iter, root) \ | |
527a5ec9 | 886 | for (iter = mem_cgroup_iter(root, NULL, NULL); \ |
9f3a0d09 | 887 | iter != NULL; \ |
527a5ec9 | 888 | iter = mem_cgroup_iter(root, iter, NULL)) |
711d3d2c | 889 | |
9f3a0d09 | 890 | #define for_each_mem_cgroup(iter) \ |
527a5ec9 | 891 | for (iter = mem_cgroup_iter(NULL, NULL, NULL); \ |
9f3a0d09 | 892 | iter != NULL; \ |
527a5ec9 | 893 | iter = mem_cgroup_iter(NULL, iter, NULL)) |
14067bb3 | 894 | |
7c5f64f8 VD |
895 | /** |
896 | * mem_cgroup_scan_tasks - iterate over tasks of a memory cgroup hierarchy | |
897 | * @memcg: hierarchy root | |
898 | * @fn: function to call for each task | |
899 | * @arg: argument passed to @fn | |
900 | * | |
901 | * This function iterates over tasks attached to @memcg or to any of its | |
902 | * descendants and calls @fn for each task. If @fn returns a non-zero | |
903 | * value, the function breaks the iteration loop and returns the value. | |
904 | * Otherwise, it will iterate over all tasks and return 0. | |
905 | * | |
906 | * This function must not be called for the root memory cgroup. | |
907 | */ | |
908 | int mem_cgroup_scan_tasks(struct mem_cgroup *memcg, | |
909 | int (*fn)(struct task_struct *, void *), void *arg) | |
910 | { | |
911 | struct mem_cgroup *iter; | |
912 | int ret = 0; | |
913 | ||
914 | BUG_ON(memcg == root_mem_cgroup); | |
915 | ||
916 | for_each_mem_cgroup_tree(iter, memcg) { | |
917 | struct css_task_iter it; | |
918 | struct task_struct *task; | |
919 | ||
920 | css_task_iter_start(&iter->css, &it); | |
921 | while (!ret && (task = css_task_iter_next(&it))) | |
922 | ret = fn(task, arg); | |
923 | css_task_iter_end(&it); | |
924 | if (ret) { | |
925 | mem_cgroup_iter_break(memcg, iter); | |
926 | break; | |
927 | } | |
928 | } | |
929 | return ret; | |
930 | } | |
931 | ||
925b7673 | 932 | /** |
dfe0e773 | 933 | * mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page |
925b7673 | 934 | * @page: the page |
fa9add64 | 935 | * @zone: zone of the page |
dfe0e773 JW |
936 | * |
937 | * This function is only safe when following the LRU page isolation | |
938 | * and putback protocol: the LRU lock must be held, and the page must | |
939 | * either be PageLRU() or the caller must have isolated/allocated it. | |
925b7673 | 940 | */ |
599d0c95 | 941 | struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgdat) |
08e552c6 | 942 | { |
ef8f2327 | 943 | struct mem_cgroup_per_node *mz; |
925b7673 | 944 | struct mem_cgroup *memcg; |
bea8c150 | 945 | struct lruvec *lruvec; |
6d12e2d8 | 946 | |
bea8c150 | 947 | if (mem_cgroup_disabled()) { |
599d0c95 | 948 | lruvec = &pgdat->lruvec; |
bea8c150 HD |
949 | goto out; |
950 | } | |
925b7673 | 951 | |
1306a85a | 952 | memcg = page->mem_cgroup; |
7512102c | 953 | /* |
dfe0e773 | 954 | * Swapcache readahead pages are added to the LRU - and |
29833315 | 955 | * possibly migrated - before they are charged. |
7512102c | 956 | */ |
29833315 JW |
957 | if (!memcg) |
958 | memcg = root_mem_cgroup; | |
7512102c | 959 | |
ef8f2327 | 960 | mz = mem_cgroup_page_nodeinfo(memcg, page); |
bea8c150 HD |
961 | lruvec = &mz->lruvec; |
962 | out: | |
963 | /* | |
964 | * Since a node can be onlined after the mem_cgroup was created, | |
965 | * we have to be prepared to initialize lruvec->zone here; | |
966 | * and if offlined then reonlined, we need to reinitialize it. | |
967 | */ | |
599d0c95 MG |
968 | if (unlikely(lruvec->pgdat != pgdat)) |
969 | lruvec->pgdat = pgdat; | |
bea8c150 | 970 | return lruvec; |
08e552c6 | 971 | } |
b69408e8 | 972 | |
925b7673 | 973 | /** |
fa9add64 HD |
974 | * mem_cgroup_update_lru_size - account for adding or removing an lru page |
975 | * @lruvec: mem_cgroup per zone lru vector | |
976 | * @lru: index of lru list the page is sitting on | |
b4536f0c | 977 | * @zid: zone id of the accounted pages |
fa9add64 | 978 | * @nr_pages: positive when adding or negative when removing |
925b7673 | 979 | * |
ca707239 HD |
980 | * This function must be called under lru_lock, just before a page is added |
981 | * to or just after a page is removed from an lru list (that ordering being | |
982 | * so as to allow it to check that lru_size 0 is consistent with list_empty). | |
3f58a829 | 983 | */ |
fa9add64 | 984 | void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, |
b4536f0c | 985 | int zid, int nr_pages) |
3f58a829 | 986 | { |
ef8f2327 | 987 | struct mem_cgroup_per_node *mz; |
fa9add64 | 988 | unsigned long *lru_size; |
ca707239 | 989 | long size; |
3f58a829 MK |
990 | |
991 | if (mem_cgroup_disabled()) | |
992 | return; | |
993 | ||
ef8f2327 | 994 | mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); |
b4536f0c | 995 | lru_size = &mz->lru_zone_size[zid][lru]; |
ca707239 HD |
996 | |
997 | if (nr_pages < 0) | |
998 | *lru_size += nr_pages; | |
999 | ||
1000 | size = *lru_size; | |
b4536f0c MH |
1001 | if (WARN_ONCE(size < 0, |
1002 | "%s(%p, %d, %d): lru_size %ld\n", | |
1003 | __func__, lruvec, lru, nr_pages, size)) { | |
ca707239 HD |
1004 | VM_BUG_ON(1); |
1005 | *lru_size = 0; | |
1006 | } | |
1007 | ||
1008 | if (nr_pages > 0) | |
1009 | *lru_size += nr_pages; | |
08e552c6 | 1010 | } |
544122e5 | 1011 | |
2314b42d | 1012 | bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg) |
c3ac9a8a | 1013 | { |
2314b42d | 1014 | struct mem_cgroup *task_memcg; |
158e0a2d | 1015 | struct task_struct *p; |
ffbdccf5 | 1016 | bool ret; |
4c4a2214 | 1017 | |
158e0a2d | 1018 | p = find_lock_task_mm(task); |
de077d22 | 1019 | if (p) { |
2314b42d | 1020 | task_memcg = get_mem_cgroup_from_mm(p->mm); |
de077d22 DR |
1021 | task_unlock(p); |
1022 | } else { | |
1023 | /* | |
1024 | * All threads may have already detached their mm's, but the oom | |
1025 | * killer still needs to detect if they have already been oom | |
1026 | * killed to prevent needlessly killing additional tasks. | |
1027 | */ | |
ffbdccf5 | 1028 | rcu_read_lock(); |
2314b42d JW |
1029 | task_memcg = mem_cgroup_from_task(task); |
1030 | css_get(&task_memcg->css); | |
ffbdccf5 | 1031 | rcu_read_unlock(); |
de077d22 | 1032 | } |
2314b42d JW |
1033 | ret = mem_cgroup_is_descendant(task_memcg, memcg); |
1034 | css_put(&task_memcg->css); | |
4c4a2214 DR |
1035 | return ret; |
1036 | } | |
1037 | ||
19942822 | 1038 | /** |
9d11ea9f | 1039 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
dad7557e | 1040 | * @memcg: the memory cgroup |
19942822 | 1041 | * |
9d11ea9f | 1042 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1043 | * pages. |
19942822 | 1044 | */ |
c0ff4b85 | 1045 | static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) |
19942822 | 1046 | { |
3e32cb2e JW |
1047 | unsigned long margin = 0; |
1048 | unsigned long count; | |
1049 | unsigned long limit; | |
9d11ea9f | 1050 | |
3e32cb2e | 1051 | count = page_counter_read(&memcg->memory); |
4db0c3c2 | 1052 | limit = READ_ONCE(memcg->memory.limit); |
3e32cb2e JW |
1053 | if (count < limit) |
1054 | margin = limit - count; | |
1055 | ||
7941d214 | 1056 | if (do_memsw_account()) { |
3e32cb2e | 1057 | count = page_counter_read(&memcg->memsw); |
4db0c3c2 | 1058 | limit = READ_ONCE(memcg->memsw.limit); |
3e32cb2e JW |
1059 | if (count <= limit) |
1060 | margin = min(margin, limit - count); | |
cbedbac3 LR |
1061 | else |
1062 | margin = 0; | |
3e32cb2e JW |
1063 | } |
1064 | ||
1065 | return margin; | |
19942822 JW |
1066 | } |
1067 | ||
32047e2a | 1068 | /* |
bdcbb659 | 1069 | * A routine for checking "mem" is under move_account() or not. |
32047e2a | 1070 | * |
bdcbb659 QH |
1071 | * Checking a cgroup is mc.from or mc.to or under hierarchy of |
1072 | * moving cgroups. This is for waiting at high-memory pressure | |
1073 | * caused by "move". | |
32047e2a | 1074 | */ |
c0ff4b85 | 1075 | static bool mem_cgroup_under_move(struct mem_cgroup *memcg) |
4b534334 | 1076 | { |
2bd9bb20 KH |
1077 | struct mem_cgroup *from; |
1078 | struct mem_cgroup *to; | |
4b534334 | 1079 | bool ret = false; |
2bd9bb20 KH |
1080 | /* |
1081 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1082 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1083 | */ | |
1084 | spin_lock(&mc.lock); | |
1085 | from = mc.from; | |
1086 | to = mc.to; | |
1087 | if (!from) | |
1088 | goto unlock; | |
3e92041d | 1089 | |
2314b42d JW |
1090 | ret = mem_cgroup_is_descendant(from, memcg) || |
1091 | mem_cgroup_is_descendant(to, memcg); | |
2bd9bb20 KH |
1092 | unlock: |
1093 | spin_unlock(&mc.lock); | |
4b534334 KH |
1094 | return ret; |
1095 | } | |
1096 | ||
c0ff4b85 | 1097 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) |
4b534334 KH |
1098 | { |
1099 | if (mc.moving_task && current != mc.moving_task) { | |
c0ff4b85 | 1100 | if (mem_cgroup_under_move(memcg)) { |
4b534334 KH |
1101 | DEFINE_WAIT(wait); |
1102 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1103 | /* moving charge context might have finished. */ | |
1104 | if (mc.moving_task) | |
1105 | schedule(); | |
1106 | finish_wait(&mc.waitq, &wait); | |
1107 | return true; | |
1108 | } | |
1109 | } | |
1110 | return false; | |
1111 | } | |
1112 | ||
71cd3113 JW |
1113 | unsigned int memcg1_stats[] = { |
1114 | MEMCG_CACHE, | |
1115 | MEMCG_RSS, | |
1116 | MEMCG_RSS_HUGE, | |
1117 | NR_SHMEM, | |
1118 | NR_FILE_MAPPED, | |
1119 | NR_FILE_DIRTY, | |
1120 | NR_WRITEBACK, | |
1121 | MEMCG_SWAP, | |
1122 | }; | |
1123 | ||
1124 | static const char *const memcg1_stat_names[] = { | |
1125 | "cache", | |
1126 | "rss", | |
1127 | "rss_huge", | |
1128 | "shmem", | |
1129 | "mapped_file", | |
1130 | "dirty", | |
1131 | "writeback", | |
1132 | "swap", | |
1133 | }; | |
1134 | ||
58cf188e | 1135 | #define K(x) ((x) << (PAGE_SHIFT-10)) |
e222432b | 1136 | /** |
58cf188e | 1137 | * mem_cgroup_print_oom_info: Print OOM information relevant to memory controller. |
e222432b BS |
1138 | * @memcg: The memory cgroup that went over limit |
1139 | * @p: Task that is going to be killed | |
1140 | * | |
1141 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1142 | * enabled | |
1143 | */ | |
1144 | void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) | |
1145 | { | |
58cf188e SZ |
1146 | struct mem_cgroup *iter; |
1147 | unsigned int i; | |
e222432b | 1148 | |
e222432b BS |
1149 | rcu_read_lock(); |
1150 | ||
2415b9f5 BV |
1151 | if (p) { |
1152 | pr_info("Task in "); | |
1153 | pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id)); | |
1154 | pr_cont(" killed as a result of limit of "); | |
1155 | } else { | |
1156 | pr_info("Memory limit reached of cgroup "); | |
1157 | } | |
1158 | ||
e61734c5 | 1159 | pr_cont_cgroup_path(memcg->css.cgroup); |
0346dadb | 1160 | pr_cont("\n"); |
e222432b | 1161 | |
e222432b BS |
1162 | rcu_read_unlock(); |
1163 | ||
3e32cb2e JW |
1164 | pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n", |
1165 | K((u64)page_counter_read(&memcg->memory)), | |
1166 | K((u64)memcg->memory.limit), memcg->memory.failcnt); | |
1167 | pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n", | |
1168 | K((u64)page_counter_read(&memcg->memsw)), | |
1169 | K((u64)memcg->memsw.limit), memcg->memsw.failcnt); | |
1170 | pr_info("kmem: usage %llukB, limit %llukB, failcnt %lu\n", | |
1171 | K((u64)page_counter_read(&memcg->kmem)), | |
1172 | K((u64)memcg->kmem.limit), memcg->kmem.failcnt); | |
58cf188e SZ |
1173 | |
1174 | for_each_mem_cgroup_tree(iter, memcg) { | |
e61734c5 TH |
1175 | pr_info("Memory cgroup stats for "); |
1176 | pr_cont_cgroup_path(iter->css.cgroup); | |
58cf188e SZ |
1177 | pr_cont(":"); |
1178 | ||
71cd3113 JW |
1179 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
1180 | if (memcg1_stats[i] == MEMCG_SWAP && !do_swap_account) | |
58cf188e | 1181 | continue; |
71cd3113 | 1182 | pr_cont(" %s:%luKB", memcg1_stat_names[i], |
ccda7f43 | 1183 | K(memcg_page_state(iter, memcg1_stats[i]))); |
58cf188e SZ |
1184 | } |
1185 | ||
1186 | for (i = 0; i < NR_LRU_LISTS; i++) | |
1187 | pr_cont(" %s:%luKB", mem_cgroup_lru_names[i], | |
1188 | K(mem_cgroup_nr_lru_pages(iter, BIT(i)))); | |
1189 | ||
1190 | pr_cont("\n"); | |
1191 | } | |
e222432b BS |
1192 | } |
1193 | ||
81d39c20 KH |
1194 | /* |
1195 | * This function returns the number of memcg under hierarchy tree. Returns | |
1196 | * 1(self count) if no children. | |
1197 | */ | |
c0ff4b85 | 1198 | static int mem_cgroup_count_children(struct mem_cgroup *memcg) |
81d39c20 KH |
1199 | { |
1200 | int num = 0; | |
7d74b06f KH |
1201 | struct mem_cgroup *iter; |
1202 | ||
c0ff4b85 | 1203 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 1204 | num++; |
81d39c20 KH |
1205 | return num; |
1206 | } | |
1207 | ||
a63d83f4 DR |
1208 | /* |
1209 | * Return the memory (and swap, if configured) limit for a memcg. | |
1210 | */ | |
7c5f64f8 | 1211 | unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg) |
a63d83f4 | 1212 | { |
3e32cb2e | 1213 | unsigned long limit; |
f3e8eb70 | 1214 | |
3e32cb2e | 1215 | limit = memcg->memory.limit; |
9a5a8f19 | 1216 | if (mem_cgroup_swappiness(memcg)) { |
3e32cb2e | 1217 | unsigned long memsw_limit; |
37e84351 | 1218 | unsigned long swap_limit; |
9a5a8f19 | 1219 | |
3e32cb2e | 1220 | memsw_limit = memcg->memsw.limit; |
37e84351 VD |
1221 | swap_limit = memcg->swap.limit; |
1222 | swap_limit = min(swap_limit, (unsigned long)total_swap_pages); | |
1223 | limit = min(limit + swap_limit, memsw_limit); | |
9a5a8f19 | 1224 | } |
9a5a8f19 | 1225 | return limit; |
a63d83f4 DR |
1226 | } |
1227 | ||
b6e6edcf | 1228 | static bool mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, |
19965460 | 1229 | int order) |
9cbb78bb | 1230 | { |
6e0fc46d DR |
1231 | struct oom_control oc = { |
1232 | .zonelist = NULL, | |
1233 | .nodemask = NULL, | |
2a966b77 | 1234 | .memcg = memcg, |
6e0fc46d DR |
1235 | .gfp_mask = gfp_mask, |
1236 | .order = order, | |
6e0fc46d | 1237 | }; |
7c5f64f8 | 1238 | bool ret; |
9cbb78bb | 1239 | |
dc56401f | 1240 | mutex_lock(&oom_lock); |
7c5f64f8 | 1241 | ret = out_of_memory(&oc); |
dc56401f | 1242 | mutex_unlock(&oom_lock); |
7c5f64f8 | 1243 | return ret; |
9cbb78bb DR |
1244 | } |
1245 | ||
ae6e71d3 MC |
1246 | #if MAX_NUMNODES > 1 |
1247 | ||
4d0c066d KH |
1248 | /** |
1249 | * test_mem_cgroup_node_reclaimable | |
dad7557e | 1250 | * @memcg: the target memcg |
4d0c066d KH |
1251 | * @nid: the node ID to be checked. |
1252 | * @noswap : specify true here if the user wants flle only information. | |
1253 | * | |
1254 | * This function returns whether the specified memcg contains any | |
1255 | * reclaimable pages on a node. Returns true if there are any reclaimable | |
1256 | * pages in the node. | |
1257 | */ | |
c0ff4b85 | 1258 | static bool test_mem_cgroup_node_reclaimable(struct mem_cgroup *memcg, |
4d0c066d KH |
1259 | int nid, bool noswap) |
1260 | { | |
c0ff4b85 | 1261 | if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_FILE)) |
4d0c066d KH |
1262 | return true; |
1263 | if (noswap || !total_swap_pages) | |
1264 | return false; | |
c0ff4b85 | 1265 | if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_ANON)) |
4d0c066d KH |
1266 | return true; |
1267 | return false; | |
1268 | ||
1269 | } | |
889976db YH |
1270 | |
1271 | /* | |
1272 | * Always updating the nodemask is not very good - even if we have an empty | |
1273 | * list or the wrong list here, we can start from some node and traverse all | |
1274 | * nodes based on the zonelist. So update the list loosely once per 10 secs. | |
1275 | * | |
1276 | */ | |
c0ff4b85 | 1277 | static void mem_cgroup_may_update_nodemask(struct mem_cgroup *memcg) |
889976db YH |
1278 | { |
1279 | int nid; | |
453a9bf3 KH |
1280 | /* |
1281 | * numainfo_events > 0 means there was at least NUMAINFO_EVENTS_TARGET | |
1282 | * pagein/pageout changes since the last update. | |
1283 | */ | |
c0ff4b85 | 1284 | if (!atomic_read(&memcg->numainfo_events)) |
453a9bf3 | 1285 | return; |
c0ff4b85 | 1286 | if (atomic_inc_return(&memcg->numainfo_updating) > 1) |
889976db YH |
1287 | return; |
1288 | ||
889976db | 1289 | /* make a nodemask where this memcg uses memory from */ |
31aaea4a | 1290 | memcg->scan_nodes = node_states[N_MEMORY]; |
889976db | 1291 | |
31aaea4a | 1292 | for_each_node_mask(nid, node_states[N_MEMORY]) { |
889976db | 1293 | |
c0ff4b85 R |
1294 | if (!test_mem_cgroup_node_reclaimable(memcg, nid, false)) |
1295 | node_clear(nid, memcg->scan_nodes); | |
889976db | 1296 | } |
453a9bf3 | 1297 | |
c0ff4b85 R |
1298 | atomic_set(&memcg->numainfo_events, 0); |
1299 | atomic_set(&memcg->numainfo_updating, 0); | |
889976db YH |
1300 | } |
1301 | ||
1302 | /* | |
1303 | * Selecting a node where we start reclaim from. Because what we need is just | |
1304 | * reducing usage counter, start from anywhere is O,K. Considering | |
1305 | * memory reclaim from current node, there are pros. and cons. | |
1306 | * | |
1307 | * Freeing memory from current node means freeing memory from a node which | |
1308 | * we'll use or we've used. So, it may make LRU bad. And if several threads | |
1309 | * hit limits, it will see a contention on a node. But freeing from remote | |
1310 | * node means more costs for memory reclaim because of memory latency. | |
1311 | * | |
1312 | * Now, we use round-robin. Better algorithm is welcomed. | |
1313 | */ | |
c0ff4b85 | 1314 | int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) |
889976db YH |
1315 | { |
1316 | int node; | |
1317 | ||
c0ff4b85 R |
1318 | mem_cgroup_may_update_nodemask(memcg); |
1319 | node = memcg->last_scanned_node; | |
889976db | 1320 | |
0edaf86c | 1321 | node = next_node_in(node, memcg->scan_nodes); |
889976db | 1322 | /* |
fda3d69b MH |
1323 | * mem_cgroup_may_update_nodemask might have seen no reclaimmable pages |
1324 | * last time it really checked all the LRUs due to rate limiting. | |
1325 | * Fallback to the current node in that case for simplicity. | |
889976db YH |
1326 | */ |
1327 | if (unlikely(node == MAX_NUMNODES)) | |
1328 | node = numa_node_id(); | |
1329 | ||
c0ff4b85 | 1330 | memcg->last_scanned_node = node; |
889976db YH |
1331 | return node; |
1332 | } | |
889976db | 1333 | #else |
c0ff4b85 | 1334 | int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) |
889976db YH |
1335 | { |
1336 | return 0; | |
1337 | } | |
1338 | #endif | |
1339 | ||
0608f43d | 1340 | static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, |
ef8f2327 | 1341 | pg_data_t *pgdat, |
0608f43d AM |
1342 | gfp_t gfp_mask, |
1343 | unsigned long *total_scanned) | |
1344 | { | |
1345 | struct mem_cgroup *victim = NULL; | |
1346 | int total = 0; | |
1347 | int loop = 0; | |
1348 | unsigned long excess; | |
1349 | unsigned long nr_scanned; | |
1350 | struct mem_cgroup_reclaim_cookie reclaim = { | |
ef8f2327 | 1351 | .pgdat = pgdat, |
0608f43d AM |
1352 | .priority = 0, |
1353 | }; | |
1354 | ||
3e32cb2e | 1355 | excess = soft_limit_excess(root_memcg); |
0608f43d AM |
1356 | |
1357 | while (1) { | |
1358 | victim = mem_cgroup_iter(root_memcg, victim, &reclaim); | |
1359 | if (!victim) { | |
1360 | loop++; | |
1361 | if (loop >= 2) { | |
1362 | /* | |
1363 | * If we have not been able to reclaim | |
1364 | * anything, it might because there are | |
1365 | * no reclaimable pages under this hierarchy | |
1366 | */ | |
1367 | if (!total) | |
1368 | break; | |
1369 | /* | |
1370 | * We want to do more targeted reclaim. | |
1371 | * excess >> 2 is not to excessive so as to | |
1372 | * reclaim too much, nor too less that we keep | |
1373 | * coming back to reclaim from this cgroup | |
1374 | */ | |
1375 | if (total >= (excess >> 2) || | |
1376 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) | |
1377 | break; | |
1378 | } | |
1379 | continue; | |
1380 | } | |
a9dd0a83 | 1381 | total += mem_cgroup_shrink_node(victim, gfp_mask, false, |
ef8f2327 | 1382 | pgdat, &nr_scanned); |
0608f43d | 1383 | *total_scanned += nr_scanned; |
3e32cb2e | 1384 | if (!soft_limit_excess(root_memcg)) |
0608f43d | 1385 | break; |
6d61ef40 | 1386 | } |
0608f43d AM |
1387 | mem_cgroup_iter_break(root_memcg, victim); |
1388 | return total; | |
6d61ef40 BS |
1389 | } |
1390 | ||
0056f4e6 JW |
1391 | #ifdef CONFIG_LOCKDEP |
1392 | static struct lockdep_map memcg_oom_lock_dep_map = { | |
1393 | .name = "memcg_oom_lock", | |
1394 | }; | |
1395 | #endif | |
1396 | ||
fb2a6fc5 JW |
1397 | static DEFINE_SPINLOCK(memcg_oom_lock); |
1398 | ||
867578cb KH |
1399 | /* |
1400 | * Check OOM-Killer is already running under our hierarchy. | |
1401 | * If someone is running, return false. | |
1402 | */ | |
fb2a6fc5 | 1403 | static bool mem_cgroup_oom_trylock(struct mem_cgroup *memcg) |
867578cb | 1404 | { |
79dfdacc | 1405 | struct mem_cgroup *iter, *failed = NULL; |
a636b327 | 1406 | |
fb2a6fc5 JW |
1407 | spin_lock(&memcg_oom_lock); |
1408 | ||
9f3a0d09 | 1409 | for_each_mem_cgroup_tree(iter, memcg) { |
23751be0 | 1410 | if (iter->oom_lock) { |
79dfdacc MH |
1411 | /* |
1412 | * this subtree of our hierarchy is already locked | |
1413 | * so we cannot give a lock. | |
1414 | */ | |
79dfdacc | 1415 | failed = iter; |
9f3a0d09 JW |
1416 | mem_cgroup_iter_break(memcg, iter); |
1417 | break; | |
23751be0 JW |
1418 | } else |
1419 | iter->oom_lock = true; | |
7d74b06f | 1420 | } |
867578cb | 1421 | |
fb2a6fc5 JW |
1422 | if (failed) { |
1423 | /* | |
1424 | * OK, we failed to lock the whole subtree so we have | |
1425 | * to clean up what we set up to the failing subtree | |
1426 | */ | |
1427 | for_each_mem_cgroup_tree(iter, memcg) { | |
1428 | if (iter == failed) { | |
1429 | mem_cgroup_iter_break(memcg, iter); | |
1430 | break; | |
1431 | } | |
1432 | iter->oom_lock = false; | |
79dfdacc | 1433 | } |
0056f4e6 JW |
1434 | } else |
1435 | mutex_acquire(&memcg_oom_lock_dep_map, 0, 1, _RET_IP_); | |
fb2a6fc5 JW |
1436 | |
1437 | spin_unlock(&memcg_oom_lock); | |
1438 | ||
1439 | return !failed; | |
a636b327 | 1440 | } |
0b7f569e | 1441 | |
fb2a6fc5 | 1442 | static void mem_cgroup_oom_unlock(struct mem_cgroup *memcg) |
0b7f569e | 1443 | { |
7d74b06f KH |
1444 | struct mem_cgroup *iter; |
1445 | ||
fb2a6fc5 | 1446 | spin_lock(&memcg_oom_lock); |
0056f4e6 | 1447 | mutex_release(&memcg_oom_lock_dep_map, 1, _RET_IP_); |
c0ff4b85 | 1448 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc | 1449 | iter->oom_lock = false; |
fb2a6fc5 | 1450 | spin_unlock(&memcg_oom_lock); |
79dfdacc MH |
1451 | } |
1452 | ||
c0ff4b85 | 1453 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1454 | { |
1455 | struct mem_cgroup *iter; | |
1456 | ||
c2b42d3c | 1457 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1458 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1459 | iter->under_oom++; |
1460 | spin_unlock(&memcg_oom_lock); | |
79dfdacc MH |
1461 | } |
1462 | ||
c0ff4b85 | 1463 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1464 | { |
1465 | struct mem_cgroup *iter; | |
1466 | ||
867578cb KH |
1467 | /* |
1468 | * When a new child is created while the hierarchy is under oom, | |
c2b42d3c | 1469 | * mem_cgroup_oom_lock() may not be called. Watch for underflow. |
867578cb | 1470 | */ |
c2b42d3c | 1471 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1472 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1473 | if (iter->under_oom > 0) |
1474 | iter->under_oom--; | |
1475 | spin_unlock(&memcg_oom_lock); | |
0b7f569e KH |
1476 | } |
1477 | ||
867578cb KH |
1478 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1479 | ||
dc98df5a | 1480 | struct oom_wait_info { |
d79154bb | 1481 | struct mem_cgroup *memcg; |
ac6424b9 | 1482 | wait_queue_entry_t wait; |
dc98df5a KH |
1483 | }; |
1484 | ||
ac6424b9 | 1485 | static int memcg_oom_wake_function(wait_queue_entry_t *wait, |
dc98df5a KH |
1486 | unsigned mode, int sync, void *arg) |
1487 | { | |
d79154bb HD |
1488 | struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg; |
1489 | struct mem_cgroup *oom_wait_memcg; | |
dc98df5a KH |
1490 | struct oom_wait_info *oom_wait_info; |
1491 | ||
1492 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
d79154bb | 1493 | oom_wait_memcg = oom_wait_info->memcg; |
dc98df5a | 1494 | |
2314b42d JW |
1495 | if (!mem_cgroup_is_descendant(wake_memcg, oom_wait_memcg) && |
1496 | !mem_cgroup_is_descendant(oom_wait_memcg, wake_memcg)) | |
dc98df5a | 1497 | return 0; |
dc98df5a KH |
1498 | return autoremove_wake_function(wait, mode, sync, arg); |
1499 | } | |
1500 | ||
c0ff4b85 | 1501 | static void memcg_oom_recover(struct mem_cgroup *memcg) |
3c11ecf4 | 1502 | { |
c2b42d3c TH |
1503 | /* |
1504 | * For the following lockless ->under_oom test, the only required | |
1505 | * guarantee is that it must see the state asserted by an OOM when | |
1506 | * this function is called as a result of userland actions | |
1507 | * triggered by the notification of the OOM. This is trivially | |
1508 | * achieved by invoking mem_cgroup_mark_under_oom() before | |
1509 | * triggering notification. | |
1510 | */ | |
1511 | if (memcg && memcg->under_oom) | |
f4b90b70 | 1512 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg); |
3c11ecf4 KH |
1513 | } |
1514 | ||
3812c8c8 | 1515 | static void mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order) |
0b7f569e | 1516 | { |
d0db7afa | 1517 | if (!current->memcg_may_oom) |
3812c8c8 | 1518 | return; |
867578cb | 1519 | /* |
49426420 JW |
1520 | * We are in the middle of the charge context here, so we |
1521 | * don't want to block when potentially sitting on a callstack | |
1522 | * that holds all kinds of filesystem and mm locks. | |
1523 | * | |
1524 | * Also, the caller may handle a failed allocation gracefully | |
1525 | * (like optional page cache readahead) and so an OOM killer | |
1526 | * invocation might not even be necessary. | |
1527 | * | |
1528 | * That's why we don't do anything here except remember the | |
1529 | * OOM context and then deal with it at the end of the page | |
1530 | * fault when the stack is unwound, the locks are released, | |
1531 | * and when we know whether the fault was overall successful. | |
867578cb | 1532 | */ |
49426420 | 1533 | css_get(&memcg->css); |
626ebc41 TH |
1534 | current->memcg_in_oom = memcg; |
1535 | current->memcg_oom_gfp_mask = mask; | |
1536 | current->memcg_oom_order = order; | |
3812c8c8 JW |
1537 | } |
1538 | ||
1539 | /** | |
1540 | * mem_cgroup_oom_synchronize - complete memcg OOM handling | |
49426420 | 1541 | * @handle: actually kill/wait or just clean up the OOM state |
3812c8c8 | 1542 | * |
49426420 JW |
1543 | * This has to be called at the end of a page fault if the memcg OOM |
1544 | * handler was enabled. | |
3812c8c8 | 1545 | * |
49426420 | 1546 | * Memcg supports userspace OOM handling where failed allocations must |
3812c8c8 JW |
1547 | * sleep on a waitqueue until the userspace task resolves the |
1548 | * situation. Sleeping directly in the charge context with all kinds | |
1549 | * of locks held is not a good idea, instead we remember an OOM state | |
1550 | * in the task and mem_cgroup_oom_synchronize() has to be called at | |
49426420 | 1551 | * the end of the page fault to complete the OOM handling. |
3812c8c8 JW |
1552 | * |
1553 | * Returns %true if an ongoing memcg OOM situation was detected and | |
49426420 | 1554 | * completed, %false otherwise. |
3812c8c8 | 1555 | */ |
49426420 | 1556 | bool mem_cgroup_oom_synchronize(bool handle) |
3812c8c8 | 1557 | { |
626ebc41 | 1558 | struct mem_cgroup *memcg = current->memcg_in_oom; |
3812c8c8 | 1559 | struct oom_wait_info owait; |
49426420 | 1560 | bool locked; |
3812c8c8 JW |
1561 | |
1562 | /* OOM is global, do not handle */ | |
3812c8c8 | 1563 | if (!memcg) |
49426420 | 1564 | return false; |
3812c8c8 | 1565 | |
7c5f64f8 | 1566 | if (!handle) |
49426420 | 1567 | goto cleanup; |
3812c8c8 JW |
1568 | |
1569 | owait.memcg = memcg; | |
1570 | owait.wait.flags = 0; | |
1571 | owait.wait.func = memcg_oom_wake_function; | |
1572 | owait.wait.private = current; | |
2055da97 | 1573 | INIT_LIST_HEAD(&owait.wait.entry); |
867578cb | 1574 | |
3812c8c8 | 1575 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
49426420 JW |
1576 | mem_cgroup_mark_under_oom(memcg); |
1577 | ||
1578 | locked = mem_cgroup_oom_trylock(memcg); | |
1579 | ||
1580 | if (locked) | |
1581 | mem_cgroup_oom_notify(memcg); | |
1582 | ||
1583 | if (locked && !memcg->oom_kill_disable) { | |
1584 | mem_cgroup_unmark_under_oom(memcg); | |
1585 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
626ebc41 TH |
1586 | mem_cgroup_out_of_memory(memcg, current->memcg_oom_gfp_mask, |
1587 | current->memcg_oom_order); | |
49426420 | 1588 | } else { |
3812c8c8 | 1589 | schedule(); |
49426420 JW |
1590 | mem_cgroup_unmark_under_oom(memcg); |
1591 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
1592 | } | |
1593 | ||
1594 | if (locked) { | |
fb2a6fc5 JW |
1595 | mem_cgroup_oom_unlock(memcg); |
1596 | /* | |
1597 | * There is no guarantee that an OOM-lock contender | |
1598 | * sees the wakeups triggered by the OOM kill | |
1599 | * uncharges. Wake any sleepers explicitely. | |
1600 | */ | |
1601 | memcg_oom_recover(memcg); | |
1602 | } | |
49426420 | 1603 | cleanup: |
626ebc41 | 1604 | current->memcg_in_oom = NULL; |
3812c8c8 | 1605 | css_put(&memcg->css); |
867578cb | 1606 | return true; |
0b7f569e KH |
1607 | } |
1608 | ||
d7365e78 | 1609 | /** |
81f8c3a4 JW |
1610 | * lock_page_memcg - lock a page->mem_cgroup binding |
1611 | * @page: the page | |
32047e2a | 1612 | * |
81f8c3a4 JW |
1613 | * This function protects unlocked LRU pages from being moved to |
1614 | * another cgroup and stabilizes their page->mem_cgroup binding. | |
d69b042f | 1615 | */ |
62cccb8c | 1616 | void lock_page_memcg(struct page *page) |
89c06bd5 KH |
1617 | { |
1618 | struct mem_cgroup *memcg; | |
6de22619 | 1619 | unsigned long flags; |
89c06bd5 | 1620 | |
6de22619 JW |
1621 | /* |
1622 | * The RCU lock is held throughout the transaction. The fast | |
1623 | * path can get away without acquiring the memcg->move_lock | |
1624 | * because page moving starts with an RCU grace period. | |
6de22619 | 1625 | */ |
d7365e78 JW |
1626 | rcu_read_lock(); |
1627 | ||
1628 | if (mem_cgroup_disabled()) | |
62cccb8c | 1629 | return; |
89c06bd5 | 1630 | again: |
1306a85a | 1631 | memcg = page->mem_cgroup; |
29833315 | 1632 | if (unlikely(!memcg)) |
62cccb8c | 1633 | return; |
d7365e78 | 1634 | |
bdcbb659 | 1635 | if (atomic_read(&memcg->moving_account) <= 0) |
62cccb8c | 1636 | return; |
89c06bd5 | 1637 | |
6de22619 | 1638 | spin_lock_irqsave(&memcg->move_lock, flags); |
1306a85a | 1639 | if (memcg != page->mem_cgroup) { |
6de22619 | 1640 | spin_unlock_irqrestore(&memcg->move_lock, flags); |
89c06bd5 KH |
1641 | goto again; |
1642 | } | |
6de22619 JW |
1643 | |
1644 | /* | |
1645 | * When charge migration first begins, we can have locked and | |
1646 | * unlocked page stat updates happening concurrently. Track | |
81f8c3a4 | 1647 | * the task who has the lock for unlock_page_memcg(). |
6de22619 JW |
1648 | */ |
1649 | memcg->move_lock_task = current; | |
1650 | memcg->move_lock_flags = flags; | |
d7365e78 | 1651 | |
62cccb8c | 1652 | return; |
89c06bd5 | 1653 | } |
81f8c3a4 | 1654 | EXPORT_SYMBOL(lock_page_memcg); |
89c06bd5 | 1655 | |
d7365e78 | 1656 | /** |
81f8c3a4 | 1657 | * unlock_page_memcg - unlock a page->mem_cgroup binding |
62cccb8c | 1658 | * @page: the page |
d7365e78 | 1659 | */ |
62cccb8c | 1660 | void unlock_page_memcg(struct page *page) |
89c06bd5 | 1661 | { |
62cccb8c JW |
1662 | struct mem_cgroup *memcg = page->mem_cgroup; |
1663 | ||
6de22619 JW |
1664 | if (memcg && memcg->move_lock_task == current) { |
1665 | unsigned long flags = memcg->move_lock_flags; | |
1666 | ||
1667 | memcg->move_lock_task = NULL; | |
1668 | memcg->move_lock_flags = 0; | |
1669 | ||
1670 | spin_unlock_irqrestore(&memcg->move_lock, flags); | |
1671 | } | |
89c06bd5 | 1672 | |
d7365e78 | 1673 | rcu_read_unlock(); |
89c06bd5 | 1674 | } |
81f8c3a4 | 1675 | EXPORT_SYMBOL(unlock_page_memcg); |
89c06bd5 | 1676 | |
cdec2e42 KH |
1677 | /* |
1678 | * size of first charge trial. "32" comes from vmscan.c's magic value. | |
1679 | * TODO: maybe necessary to use big numbers in big irons. | |
1680 | */ | |
7ec99d62 | 1681 | #define CHARGE_BATCH 32U |
cdec2e42 KH |
1682 | struct memcg_stock_pcp { |
1683 | struct mem_cgroup *cached; /* this never be root cgroup */ | |
11c9ea4e | 1684 | unsigned int nr_pages; |
cdec2e42 | 1685 | struct work_struct work; |
26fe6168 | 1686 | unsigned long flags; |
a0db00fc | 1687 | #define FLUSHING_CACHED_CHARGE 0 |
cdec2e42 KH |
1688 | }; |
1689 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); | |
9f50fad6 | 1690 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 | 1691 | |
a0956d54 SS |
1692 | /** |
1693 | * consume_stock: Try to consume stocked charge on this cpu. | |
1694 | * @memcg: memcg to consume from. | |
1695 | * @nr_pages: how many pages to charge. | |
1696 | * | |
1697 | * The charges will only happen if @memcg matches the current cpu's memcg | |
1698 | * stock, and at least @nr_pages are available in that stock. Failure to | |
1699 | * service an allocation will refill the stock. | |
1700 | * | |
1701 | * returns true if successful, false otherwise. | |
cdec2e42 | 1702 | */ |
a0956d54 | 1703 | static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
1704 | { |
1705 | struct memcg_stock_pcp *stock; | |
db2ba40c | 1706 | unsigned long flags; |
3e32cb2e | 1707 | bool ret = false; |
cdec2e42 | 1708 | |
a0956d54 | 1709 | if (nr_pages > CHARGE_BATCH) |
3e32cb2e | 1710 | return ret; |
a0956d54 | 1711 | |
db2ba40c JW |
1712 | local_irq_save(flags); |
1713 | ||
1714 | stock = this_cpu_ptr(&memcg_stock); | |
3e32cb2e | 1715 | if (memcg == stock->cached && stock->nr_pages >= nr_pages) { |
a0956d54 | 1716 | stock->nr_pages -= nr_pages; |
3e32cb2e JW |
1717 | ret = true; |
1718 | } | |
db2ba40c JW |
1719 | |
1720 | local_irq_restore(flags); | |
1721 | ||
cdec2e42 KH |
1722 | return ret; |
1723 | } | |
1724 | ||
1725 | /* | |
3e32cb2e | 1726 | * Returns stocks cached in percpu and reset cached information. |
cdec2e42 KH |
1727 | */ |
1728 | static void drain_stock(struct memcg_stock_pcp *stock) | |
1729 | { | |
1730 | struct mem_cgroup *old = stock->cached; | |
1731 | ||
11c9ea4e | 1732 | if (stock->nr_pages) { |
3e32cb2e | 1733 | page_counter_uncharge(&old->memory, stock->nr_pages); |
7941d214 | 1734 | if (do_memsw_account()) |
3e32cb2e | 1735 | page_counter_uncharge(&old->memsw, stock->nr_pages); |
e8ea14cc | 1736 | css_put_many(&old->css, stock->nr_pages); |
11c9ea4e | 1737 | stock->nr_pages = 0; |
cdec2e42 KH |
1738 | } |
1739 | stock->cached = NULL; | |
cdec2e42 KH |
1740 | } |
1741 | ||
cdec2e42 KH |
1742 | static void drain_local_stock(struct work_struct *dummy) |
1743 | { | |
db2ba40c JW |
1744 | struct memcg_stock_pcp *stock; |
1745 | unsigned long flags; | |
1746 | ||
1747 | local_irq_save(flags); | |
1748 | ||
1749 | stock = this_cpu_ptr(&memcg_stock); | |
cdec2e42 | 1750 | drain_stock(stock); |
26fe6168 | 1751 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
db2ba40c JW |
1752 | |
1753 | local_irq_restore(flags); | |
cdec2e42 KH |
1754 | } |
1755 | ||
1756 | /* | |
3e32cb2e | 1757 | * Cache charges(val) to local per_cpu area. |
320cc51d | 1758 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 1759 | */ |
c0ff4b85 | 1760 | static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 | 1761 | { |
db2ba40c JW |
1762 | struct memcg_stock_pcp *stock; |
1763 | unsigned long flags; | |
1764 | ||
1765 | local_irq_save(flags); | |
cdec2e42 | 1766 | |
db2ba40c | 1767 | stock = this_cpu_ptr(&memcg_stock); |
c0ff4b85 | 1768 | if (stock->cached != memcg) { /* reset if necessary */ |
cdec2e42 | 1769 | drain_stock(stock); |
c0ff4b85 | 1770 | stock->cached = memcg; |
cdec2e42 | 1771 | } |
11c9ea4e | 1772 | stock->nr_pages += nr_pages; |
db2ba40c JW |
1773 | |
1774 | local_irq_restore(flags); | |
cdec2e42 KH |
1775 | } |
1776 | ||
1777 | /* | |
c0ff4b85 | 1778 | * Drains all per-CPU charge caches for given root_memcg resp. subtree |
6d3d6aa2 | 1779 | * of the hierarchy under it. |
cdec2e42 | 1780 | */ |
6d3d6aa2 | 1781 | static void drain_all_stock(struct mem_cgroup *root_memcg) |
cdec2e42 | 1782 | { |
26fe6168 | 1783 | int cpu, curcpu; |
d38144b7 | 1784 | |
6d3d6aa2 JW |
1785 | /* If someone's already draining, avoid adding running more workers. */ |
1786 | if (!mutex_trylock(&percpu_charge_mutex)) | |
1787 | return; | |
cdec2e42 | 1788 | /* Notify other cpus that system-wide "drain" is running */ |
cdec2e42 | 1789 | get_online_cpus(); |
5af12d0e | 1790 | curcpu = get_cpu(); |
cdec2e42 KH |
1791 | for_each_online_cpu(cpu) { |
1792 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
c0ff4b85 | 1793 | struct mem_cgroup *memcg; |
26fe6168 | 1794 | |
c0ff4b85 R |
1795 | memcg = stock->cached; |
1796 | if (!memcg || !stock->nr_pages) | |
26fe6168 | 1797 | continue; |
2314b42d | 1798 | if (!mem_cgroup_is_descendant(memcg, root_memcg)) |
3e92041d | 1799 | continue; |
d1a05b69 MH |
1800 | if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { |
1801 | if (cpu == curcpu) | |
1802 | drain_local_stock(&stock->work); | |
1803 | else | |
1804 | schedule_work_on(cpu, &stock->work); | |
1805 | } | |
cdec2e42 | 1806 | } |
5af12d0e | 1807 | put_cpu(); |
f894ffa8 | 1808 | put_online_cpus(); |
9f50fad6 | 1809 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
1810 | } |
1811 | ||
308167fc | 1812 | static int memcg_hotplug_cpu_dead(unsigned int cpu) |
cdec2e42 | 1813 | { |
cdec2e42 KH |
1814 | struct memcg_stock_pcp *stock; |
1815 | ||
cdec2e42 KH |
1816 | stock = &per_cpu(memcg_stock, cpu); |
1817 | drain_stock(stock); | |
308167fc | 1818 | return 0; |
cdec2e42 KH |
1819 | } |
1820 | ||
f7e1cb6e JW |
1821 | static void reclaim_high(struct mem_cgroup *memcg, |
1822 | unsigned int nr_pages, | |
1823 | gfp_t gfp_mask) | |
1824 | { | |
1825 | do { | |
1826 | if (page_counter_read(&memcg->memory) <= memcg->high) | |
1827 | continue; | |
31176c78 | 1828 | mem_cgroup_event(memcg, MEMCG_HIGH); |
f7e1cb6e JW |
1829 | try_to_free_mem_cgroup_pages(memcg, nr_pages, gfp_mask, true); |
1830 | } while ((memcg = parent_mem_cgroup(memcg))); | |
1831 | } | |
1832 | ||
1833 | static void high_work_func(struct work_struct *work) | |
1834 | { | |
1835 | struct mem_cgroup *memcg; | |
1836 | ||
1837 | memcg = container_of(work, struct mem_cgroup, high_work); | |
1838 | reclaim_high(memcg, CHARGE_BATCH, GFP_KERNEL); | |
1839 | } | |
1840 | ||
b23afb93 TH |
1841 | /* |
1842 | * Scheduled by try_charge() to be executed from the userland return path | |
1843 | * and reclaims memory over the high limit. | |
1844 | */ | |
1845 | void mem_cgroup_handle_over_high(void) | |
1846 | { | |
1847 | unsigned int nr_pages = current->memcg_nr_pages_over_high; | |
f7e1cb6e | 1848 | struct mem_cgroup *memcg; |
b23afb93 TH |
1849 | |
1850 | if (likely(!nr_pages)) | |
1851 | return; | |
1852 | ||
f7e1cb6e JW |
1853 | memcg = get_mem_cgroup_from_mm(current->mm); |
1854 | reclaim_high(memcg, nr_pages, GFP_KERNEL); | |
b23afb93 TH |
1855 | css_put(&memcg->css); |
1856 | current->memcg_nr_pages_over_high = 0; | |
1857 | } | |
1858 | ||
00501b53 JW |
1859 | static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, |
1860 | unsigned int nr_pages) | |
8a9f3ccd | 1861 | { |
7ec99d62 | 1862 | unsigned int batch = max(CHARGE_BATCH, nr_pages); |
9b130619 | 1863 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; |
6539cc05 | 1864 | struct mem_cgroup *mem_over_limit; |
3e32cb2e | 1865 | struct page_counter *counter; |
6539cc05 | 1866 | unsigned long nr_reclaimed; |
b70a2a21 JW |
1867 | bool may_swap = true; |
1868 | bool drained = false; | |
a636b327 | 1869 | |
ce00a967 | 1870 | if (mem_cgroup_is_root(memcg)) |
10d53c74 | 1871 | return 0; |
6539cc05 | 1872 | retry: |
b6b6cc72 | 1873 | if (consume_stock(memcg, nr_pages)) |
10d53c74 | 1874 | return 0; |
8a9f3ccd | 1875 | |
7941d214 | 1876 | if (!do_memsw_account() || |
6071ca52 JW |
1877 | page_counter_try_charge(&memcg->memsw, batch, &counter)) { |
1878 | if (page_counter_try_charge(&memcg->memory, batch, &counter)) | |
6539cc05 | 1879 | goto done_restock; |
7941d214 | 1880 | if (do_memsw_account()) |
3e32cb2e JW |
1881 | page_counter_uncharge(&memcg->memsw, batch); |
1882 | mem_over_limit = mem_cgroup_from_counter(counter, memory); | |
3fbe7244 | 1883 | } else { |
3e32cb2e | 1884 | mem_over_limit = mem_cgroup_from_counter(counter, memsw); |
b70a2a21 | 1885 | may_swap = false; |
3fbe7244 | 1886 | } |
7a81b88c | 1887 | |
6539cc05 JW |
1888 | if (batch > nr_pages) { |
1889 | batch = nr_pages; | |
1890 | goto retry; | |
1891 | } | |
6d61ef40 | 1892 | |
06b078fc JW |
1893 | /* |
1894 | * Unlike in global OOM situations, memcg is not in a physical | |
1895 | * memory shortage. Allow dying and OOM-killed tasks to | |
1896 | * bypass the last charges so that they can exit quickly and | |
1897 | * free their memory. | |
1898 | */ | |
1899 | if (unlikely(test_thread_flag(TIF_MEMDIE) || | |
1900 | fatal_signal_pending(current) || | |
1901 | current->flags & PF_EXITING)) | |
10d53c74 | 1902 | goto force; |
06b078fc | 1903 | |
89a28483 JW |
1904 | /* |
1905 | * Prevent unbounded recursion when reclaim operations need to | |
1906 | * allocate memory. This might exceed the limits temporarily, | |
1907 | * but we prefer facilitating memory reclaim and getting back | |
1908 | * under the limit over triggering OOM kills in these cases. | |
1909 | */ | |
1910 | if (unlikely(current->flags & PF_MEMALLOC)) | |
1911 | goto force; | |
1912 | ||
06b078fc JW |
1913 | if (unlikely(task_in_memcg_oom(current))) |
1914 | goto nomem; | |
1915 | ||
d0164adc | 1916 | if (!gfpflags_allow_blocking(gfp_mask)) |
6539cc05 | 1917 | goto nomem; |
4b534334 | 1918 | |
31176c78 | 1919 | mem_cgroup_event(mem_over_limit, MEMCG_MAX); |
241994ed | 1920 | |
b70a2a21 JW |
1921 | nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages, |
1922 | gfp_mask, may_swap); | |
6539cc05 | 1923 | |
61e02c74 | 1924 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
6539cc05 | 1925 | goto retry; |
28c34c29 | 1926 | |
b70a2a21 | 1927 | if (!drained) { |
6d3d6aa2 | 1928 | drain_all_stock(mem_over_limit); |
b70a2a21 JW |
1929 | drained = true; |
1930 | goto retry; | |
1931 | } | |
1932 | ||
28c34c29 JW |
1933 | if (gfp_mask & __GFP_NORETRY) |
1934 | goto nomem; | |
6539cc05 JW |
1935 | /* |
1936 | * Even though the limit is exceeded at this point, reclaim | |
1937 | * may have been able to free some pages. Retry the charge | |
1938 | * before killing the task. | |
1939 | * | |
1940 | * Only for regular pages, though: huge pages are rather | |
1941 | * unlikely to succeed so close to the limit, and we fall back | |
1942 | * to regular pages anyway in case of failure. | |
1943 | */ | |
61e02c74 | 1944 | if (nr_reclaimed && nr_pages <= (1 << PAGE_ALLOC_COSTLY_ORDER)) |
6539cc05 JW |
1945 | goto retry; |
1946 | /* | |
1947 | * At task move, charge accounts can be doubly counted. So, it's | |
1948 | * better to wait until the end of task_move if something is going on. | |
1949 | */ | |
1950 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
1951 | goto retry; | |
1952 | ||
9b130619 JW |
1953 | if (nr_retries--) |
1954 | goto retry; | |
1955 | ||
06b078fc | 1956 | if (gfp_mask & __GFP_NOFAIL) |
10d53c74 | 1957 | goto force; |
06b078fc | 1958 | |
6539cc05 | 1959 | if (fatal_signal_pending(current)) |
10d53c74 | 1960 | goto force; |
6539cc05 | 1961 | |
31176c78 | 1962 | mem_cgroup_event(mem_over_limit, MEMCG_OOM); |
241994ed | 1963 | |
3608de07 JM |
1964 | mem_cgroup_oom(mem_over_limit, gfp_mask, |
1965 | get_order(nr_pages * PAGE_SIZE)); | |
7a81b88c | 1966 | nomem: |
6d1fdc48 | 1967 | if (!(gfp_mask & __GFP_NOFAIL)) |
3168ecbe | 1968 | return -ENOMEM; |
10d53c74 TH |
1969 | force: |
1970 | /* | |
1971 | * The allocation either can't fail or will lead to more memory | |
1972 | * being freed very soon. Allow memory usage go over the limit | |
1973 | * temporarily by force charging it. | |
1974 | */ | |
1975 | page_counter_charge(&memcg->memory, nr_pages); | |
7941d214 | 1976 | if (do_memsw_account()) |
10d53c74 TH |
1977 | page_counter_charge(&memcg->memsw, nr_pages); |
1978 | css_get_many(&memcg->css, nr_pages); | |
1979 | ||
1980 | return 0; | |
6539cc05 JW |
1981 | |
1982 | done_restock: | |
e8ea14cc | 1983 | css_get_many(&memcg->css, batch); |
6539cc05 JW |
1984 | if (batch > nr_pages) |
1985 | refill_stock(memcg, batch - nr_pages); | |
b23afb93 | 1986 | |
241994ed | 1987 | /* |
b23afb93 TH |
1988 | * If the hierarchy is above the normal consumption range, schedule |
1989 | * reclaim on returning to userland. We can perform reclaim here | |
71baba4b | 1990 | * if __GFP_RECLAIM but let's always punt for simplicity and so that |
b23afb93 TH |
1991 | * GFP_KERNEL can consistently be used during reclaim. @memcg is |
1992 | * not recorded as it most likely matches current's and won't | |
1993 | * change in the meantime. As high limit is checked again before | |
1994 | * reclaim, the cost of mismatch is negligible. | |
241994ed JW |
1995 | */ |
1996 | do { | |
b23afb93 | 1997 | if (page_counter_read(&memcg->memory) > memcg->high) { |
f7e1cb6e JW |
1998 | /* Don't bother a random interrupted task */ |
1999 | if (in_interrupt()) { | |
2000 | schedule_work(&memcg->high_work); | |
2001 | break; | |
2002 | } | |
9516a18a | 2003 | current->memcg_nr_pages_over_high += batch; |
b23afb93 TH |
2004 | set_notify_resume(current); |
2005 | break; | |
2006 | } | |
241994ed | 2007 | } while ((memcg = parent_mem_cgroup(memcg))); |
10d53c74 TH |
2008 | |
2009 | return 0; | |
7a81b88c | 2010 | } |
8a9f3ccd | 2011 | |
00501b53 | 2012 | static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) |
a3032a2c | 2013 | { |
ce00a967 JW |
2014 | if (mem_cgroup_is_root(memcg)) |
2015 | return; | |
2016 | ||
3e32cb2e | 2017 | page_counter_uncharge(&memcg->memory, nr_pages); |
7941d214 | 2018 | if (do_memsw_account()) |
3e32cb2e | 2019 | page_counter_uncharge(&memcg->memsw, nr_pages); |
ce00a967 | 2020 | |
e8ea14cc | 2021 | css_put_many(&memcg->css, nr_pages); |
d01dd17f KH |
2022 | } |
2023 | ||
0a31bc97 JW |
2024 | static void lock_page_lru(struct page *page, int *isolated) |
2025 | { | |
2026 | struct zone *zone = page_zone(page); | |
2027 | ||
a52633d8 | 2028 | spin_lock_irq(zone_lru_lock(zone)); |
0a31bc97 JW |
2029 | if (PageLRU(page)) { |
2030 | struct lruvec *lruvec; | |
2031 | ||
599d0c95 | 2032 | lruvec = mem_cgroup_page_lruvec(page, zone->zone_pgdat); |
0a31bc97 JW |
2033 | ClearPageLRU(page); |
2034 | del_page_from_lru_list(page, lruvec, page_lru(page)); | |
2035 | *isolated = 1; | |
2036 | } else | |
2037 | *isolated = 0; | |
2038 | } | |
2039 | ||
2040 | static void unlock_page_lru(struct page *page, int isolated) | |
2041 | { | |
2042 | struct zone *zone = page_zone(page); | |
2043 | ||
2044 | if (isolated) { | |
2045 | struct lruvec *lruvec; | |
2046 | ||
599d0c95 | 2047 | lruvec = mem_cgroup_page_lruvec(page, zone->zone_pgdat); |
0a31bc97 JW |
2048 | VM_BUG_ON_PAGE(PageLRU(page), page); |
2049 | SetPageLRU(page); | |
2050 | add_page_to_lru_list(page, lruvec, page_lru(page)); | |
2051 | } | |
a52633d8 | 2052 | spin_unlock_irq(zone_lru_lock(zone)); |
0a31bc97 JW |
2053 | } |
2054 | ||
00501b53 | 2055 | static void commit_charge(struct page *page, struct mem_cgroup *memcg, |
6abb5a86 | 2056 | bool lrucare) |
7a81b88c | 2057 | { |
0a31bc97 | 2058 | int isolated; |
9ce70c02 | 2059 | |
1306a85a | 2060 | VM_BUG_ON_PAGE(page->mem_cgroup, page); |
9ce70c02 HD |
2061 | |
2062 | /* | |
2063 | * In some cases, SwapCache and FUSE(splice_buf->radixtree), the page | |
2064 | * may already be on some other mem_cgroup's LRU. Take care of it. | |
2065 | */ | |
0a31bc97 JW |
2066 | if (lrucare) |
2067 | lock_page_lru(page, &isolated); | |
9ce70c02 | 2068 | |
0a31bc97 JW |
2069 | /* |
2070 | * Nobody should be changing or seriously looking at | |
1306a85a | 2071 | * page->mem_cgroup at this point: |
0a31bc97 JW |
2072 | * |
2073 | * - the page is uncharged | |
2074 | * | |
2075 | * - the page is off-LRU | |
2076 | * | |
2077 | * - an anonymous fault has exclusive page access, except for | |
2078 | * a locked page table | |
2079 | * | |
2080 | * - a page cache insertion, a swapin fault, or a migration | |
2081 | * have the page locked | |
2082 | */ | |
1306a85a | 2083 | page->mem_cgroup = memcg; |
9ce70c02 | 2084 | |
0a31bc97 JW |
2085 | if (lrucare) |
2086 | unlock_page_lru(page, isolated); | |
7a81b88c | 2087 | } |
66e1707b | 2088 | |
127424c8 | 2089 | #ifndef CONFIG_SLOB |
f3bb3043 | 2090 | static int memcg_alloc_cache_id(void) |
55007d84 | 2091 | { |
f3bb3043 VD |
2092 | int id, size; |
2093 | int err; | |
2094 | ||
dbcf73e2 | 2095 | id = ida_simple_get(&memcg_cache_ida, |
f3bb3043 VD |
2096 | 0, MEMCG_CACHES_MAX_SIZE, GFP_KERNEL); |
2097 | if (id < 0) | |
2098 | return id; | |
55007d84 | 2099 | |
dbcf73e2 | 2100 | if (id < memcg_nr_cache_ids) |
f3bb3043 VD |
2101 | return id; |
2102 | ||
2103 | /* | |
2104 | * There's no space for the new id in memcg_caches arrays, | |
2105 | * so we have to grow them. | |
2106 | */ | |
05257a1a | 2107 | down_write(&memcg_cache_ids_sem); |
f3bb3043 VD |
2108 | |
2109 | size = 2 * (id + 1); | |
55007d84 GC |
2110 | if (size < MEMCG_CACHES_MIN_SIZE) |
2111 | size = MEMCG_CACHES_MIN_SIZE; | |
2112 | else if (size > MEMCG_CACHES_MAX_SIZE) | |
2113 | size = MEMCG_CACHES_MAX_SIZE; | |
2114 | ||
f3bb3043 | 2115 | err = memcg_update_all_caches(size); |
60d3fd32 VD |
2116 | if (!err) |
2117 | err = memcg_update_all_list_lrus(size); | |
05257a1a VD |
2118 | if (!err) |
2119 | memcg_nr_cache_ids = size; | |
2120 | ||
2121 | up_write(&memcg_cache_ids_sem); | |
2122 | ||
f3bb3043 | 2123 | if (err) { |
dbcf73e2 | 2124 | ida_simple_remove(&memcg_cache_ida, id); |
f3bb3043 VD |
2125 | return err; |
2126 | } | |
2127 | return id; | |
2128 | } | |
2129 | ||
2130 | static void memcg_free_cache_id(int id) | |
2131 | { | |
dbcf73e2 | 2132 | ida_simple_remove(&memcg_cache_ida, id); |
55007d84 GC |
2133 | } |
2134 | ||
d5b3cf71 | 2135 | struct memcg_kmem_cache_create_work { |
5722d094 VD |
2136 | struct mem_cgroup *memcg; |
2137 | struct kmem_cache *cachep; | |
2138 | struct work_struct work; | |
2139 | }; | |
2140 | ||
d5b3cf71 | 2141 | static void memcg_kmem_cache_create_func(struct work_struct *w) |
d7f25f8a | 2142 | { |
d5b3cf71 VD |
2143 | struct memcg_kmem_cache_create_work *cw = |
2144 | container_of(w, struct memcg_kmem_cache_create_work, work); | |
5722d094 VD |
2145 | struct mem_cgroup *memcg = cw->memcg; |
2146 | struct kmem_cache *cachep = cw->cachep; | |
d7f25f8a | 2147 | |
d5b3cf71 | 2148 | memcg_create_kmem_cache(memcg, cachep); |
bd673145 | 2149 | |
5722d094 | 2150 | css_put(&memcg->css); |
d7f25f8a GC |
2151 | kfree(cw); |
2152 | } | |
2153 | ||
2154 | /* | |
2155 | * Enqueue the creation of a per-memcg kmem_cache. | |
d7f25f8a | 2156 | */ |
d5b3cf71 VD |
2157 | static void __memcg_schedule_kmem_cache_create(struct mem_cgroup *memcg, |
2158 | struct kmem_cache *cachep) | |
d7f25f8a | 2159 | { |
d5b3cf71 | 2160 | struct memcg_kmem_cache_create_work *cw; |
d7f25f8a | 2161 | |
776ed0f0 | 2162 | cw = kmalloc(sizeof(*cw), GFP_NOWAIT); |
8135be5a | 2163 | if (!cw) |
d7f25f8a | 2164 | return; |
8135be5a VD |
2165 | |
2166 | css_get(&memcg->css); | |
d7f25f8a GC |
2167 | |
2168 | cw->memcg = memcg; | |
2169 | cw->cachep = cachep; | |
d5b3cf71 | 2170 | INIT_WORK(&cw->work, memcg_kmem_cache_create_func); |
d7f25f8a | 2171 | |
17cc4dfe | 2172 | queue_work(memcg_kmem_cache_wq, &cw->work); |
d7f25f8a GC |
2173 | } |
2174 | ||
d5b3cf71 VD |
2175 | static void memcg_schedule_kmem_cache_create(struct mem_cgroup *memcg, |
2176 | struct kmem_cache *cachep) | |
0e9d92f2 GC |
2177 | { |
2178 | /* | |
2179 | * We need to stop accounting when we kmalloc, because if the | |
2180 | * corresponding kmalloc cache is not yet created, the first allocation | |
d5b3cf71 | 2181 | * in __memcg_schedule_kmem_cache_create will recurse. |
0e9d92f2 GC |
2182 | * |
2183 | * However, it is better to enclose the whole function. Depending on | |
2184 | * the debugging options enabled, INIT_WORK(), for instance, can | |
2185 | * trigger an allocation. This too, will make us recurse. Because at | |
2186 | * this point we can't allow ourselves back into memcg_kmem_get_cache, | |
2187 | * the safest choice is to do it like this, wrapping the whole function. | |
2188 | */ | |
6f185c29 | 2189 | current->memcg_kmem_skip_account = 1; |
d5b3cf71 | 2190 | __memcg_schedule_kmem_cache_create(memcg, cachep); |
6f185c29 | 2191 | current->memcg_kmem_skip_account = 0; |
0e9d92f2 | 2192 | } |
c67a8a68 | 2193 | |
45264778 VD |
2194 | static inline bool memcg_kmem_bypass(void) |
2195 | { | |
2196 | if (in_interrupt() || !current->mm || (current->flags & PF_KTHREAD)) | |
2197 | return true; | |
2198 | return false; | |
2199 | } | |
2200 | ||
2201 | /** | |
2202 | * memcg_kmem_get_cache: select the correct per-memcg cache for allocation | |
2203 | * @cachep: the original global kmem cache | |
2204 | * | |
d7f25f8a GC |
2205 | * Return the kmem_cache we're supposed to use for a slab allocation. |
2206 | * We try to use the current memcg's version of the cache. | |
2207 | * | |
45264778 VD |
2208 | * If the cache does not exist yet, if we are the first user of it, we |
2209 | * create it asynchronously in a workqueue and let the current allocation | |
2210 | * go through with the original cache. | |
d7f25f8a | 2211 | * |
45264778 VD |
2212 | * This function takes a reference to the cache it returns to assure it |
2213 | * won't get destroyed while we are working with it. Once the caller is | |
2214 | * done with it, memcg_kmem_put_cache() must be called to release the | |
2215 | * reference. | |
d7f25f8a | 2216 | */ |
45264778 | 2217 | struct kmem_cache *memcg_kmem_get_cache(struct kmem_cache *cachep) |
d7f25f8a GC |
2218 | { |
2219 | struct mem_cgroup *memcg; | |
959c8963 | 2220 | struct kmem_cache *memcg_cachep; |
2a4db7eb | 2221 | int kmemcg_id; |
d7f25f8a | 2222 | |
f7ce3190 | 2223 | VM_BUG_ON(!is_root_cache(cachep)); |
d7f25f8a | 2224 | |
45264778 | 2225 | if (memcg_kmem_bypass()) |
230e9fc2 VD |
2226 | return cachep; |
2227 | ||
9d100c5e | 2228 | if (current->memcg_kmem_skip_account) |
0e9d92f2 GC |
2229 | return cachep; |
2230 | ||
8135be5a | 2231 | memcg = get_mem_cgroup_from_mm(current->mm); |
4db0c3c2 | 2232 | kmemcg_id = READ_ONCE(memcg->kmemcg_id); |
2a4db7eb | 2233 | if (kmemcg_id < 0) |
ca0dde97 | 2234 | goto out; |
d7f25f8a | 2235 | |
2a4db7eb | 2236 | memcg_cachep = cache_from_memcg_idx(cachep, kmemcg_id); |
8135be5a VD |
2237 | if (likely(memcg_cachep)) |
2238 | return memcg_cachep; | |
ca0dde97 LZ |
2239 | |
2240 | /* | |
2241 | * If we are in a safe context (can wait, and not in interrupt | |
2242 | * context), we could be be predictable and return right away. | |
2243 | * This would guarantee that the allocation being performed | |
2244 | * already belongs in the new cache. | |
2245 | * | |
2246 | * However, there are some clashes that can arrive from locking. | |
2247 | * For instance, because we acquire the slab_mutex while doing | |
776ed0f0 VD |
2248 | * memcg_create_kmem_cache, this means no further allocation |
2249 | * could happen with the slab_mutex held. So it's better to | |
2250 | * defer everything. | |
ca0dde97 | 2251 | */ |
d5b3cf71 | 2252 | memcg_schedule_kmem_cache_create(memcg, cachep); |
ca0dde97 | 2253 | out: |
8135be5a | 2254 | css_put(&memcg->css); |
ca0dde97 | 2255 | return cachep; |
d7f25f8a | 2256 | } |
d7f25f8a | 2257 | |
45264778 VD |
2258 | /** |
2259 | * memcg_kmem_put_cache: drop reference taken by memcg_kmem_get_cache | |
2260 | * @cachep: the cache returned by memcg_kmem_get_cache | |
2261 | */ | |
2262 | void memcg_kmem_put_cache(struct kmem_cache *cachep) | |
8135be5a VD |
2263 | { |
2264 | if (!is_root_cache(cachep)) | |
f7ce3190 | 2265 | css_put(&cachep->memcg_params.memcg->css); |
8135be5a VD |
2266 | } |
2267 | ||
45264778 VD |
2268 | /** |
2269 | * memcg_kmem_charge: charge a kmem page | |
2270 | * @page: page to charge | |
2271 | * @gfp: reclaim mode | |
2272 | * @order: allocation order | |
2273 | * @memcg: memory cgroup to charge | |
2274 | * | |
2275 | * Returns 0 on success, an error code on failure. | |
2276 | */ | |
2277 | int memcg_kmem_charge_memcg(struct page *page, gfp_t gfp, int order, | |
2278 | struct mem_cgroup *memcg) | |
7ae1e1d0 | 2279 | { |
f3ccb2c4 VD |
2280 | unsigned int nr_pages = 1 << order; |
2281 | struct page_counter *counter; | |
7ae1e1d0 GC |
2282 | int ret; |
2283 | ||
f3ccb2c4 | 2284 | ret = try_charge(memcg, gfp, nr_pages); |
52c29b04 | 2285 | if (ret) |
f3ccb2c4 | 2286 | return ret; |
52c29b04 JW |
2287 | |
2288 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && | |
2289 | !page_counter_try_charge(&memcg->kmem, nr_pages, &counter)) { | |
2290 | cancel_charge(memcg, nr_pages); | |
2291 | return -ENOMEM; | |
7ae1e1d0 GC |
2292 | } |
2293 | ||
f3ccb2c4 | 2294 | page->mem_cgroup = memcg; |
7ae1e1d0 | 2295 | |
f3ccb2c4 | 2296 | return 0; |
7ae1e1d0 GC |
2297 | } |
2298 | ||
45264778 VD |
2299 | /** |
2300 | * memcg_kmem_charge: charge a kmem page to the current memory cgroup | |
2301 | * @page: page to charge | |
2302 | * @gfp: reclaim mode | |
2303 | * @order: allocation order | |
2304 | * | |
2305 | * Returns 0 on success, an error code on failure. | |
2306 | */ | |
2307 | int memcg_kmem_charge(struct page *page, gfp_t gfp, int order) | |
7ae1e1d0 | 2308 | { |
f3ccb2c4 | 2309 | struct mem_cgroup *memcg; |
fcff7d7e | 2310 | int ret = 0; |
7ae1e1d0 | 2311 | |
45264778 VD |
2312 | if (memcg_kmem_bypass()) |
2313 | return 0; | |
2314 | ||
f3ccb2c4 | 2315 | memcg = get_mem_cgroup_from_mm(current->mm); |
c4159a75 | 2316 | if (!mem_cgroup_is_root(memcg)) { |
45264778 | 2317 | ret = memcg_kmem_charge_memcg(page, gfp, order, memcg); |
c4159a75 VD |
2318 | if (!ret) |
2319 | __SetPageKmemcg(page); | |
2320 | } | |
7ae1e1d0 | 2321 | css_put(&memcg->css); |
d05e83a6 | 2322 | return ret; |
7ae1e1d0 | 2323 | } |
45264778 VD |
2324 | /** |
2325 | * memcg_kmem_uncharge: uncharge a kmem page | |
2326 | * @page: page to uncharge | |
2327 | * @order: allocation order | |
2328 | */ | |
2329 | void memcg_kmem_uncharge(struct page *page, int order) | |
7ae1e1d0 | 2330 | { |
1306a85a | 2331 | struct mem_cgroup *memcg = page->mem_cgroup; |
f3ccb2c4 | 2332 | unsigned int nr_pages = 1 << order; |
7ae1e1d0 | 2333 | |
7ae1e1d0 GC |
2334 | if (!memcg) |
2335 | return; | |
2336 | ||
309381fe | 2337 | VM_BUG_ON_PAGE(mem_cgroup_is_root(memcg), page); |
29833315 | 2338 | |
52c29b04 JW |
2339 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
2340 | page_counter_uncharge(&memcg->kmem, nr_pages); | |
2341 | ||
f3ccb2c4 | 2342 | page_counter_uncharge(&memcg->memory, nr_pages); |
7941d214 | 2343 | if (do_memsw_account()) |
f3ccb2c4 | 2344 | page_counter_uncharge(&memcg->memsw, nr_pages); |
60d3fd32 | 2345 | |
1306a85a | 2346 | page->mem_cgroup = NULL; |
c4159a75 VD |
2347 | |
2348 | /* slab pages do not have PageKmemcg flag set */ | |
2349 | if (PageKmemcg(page)) | |
2350 | __ClearPageKmemcg(page); | |
2351 | ||
f3ccb2c4 | 2352 | css_put_many(&memcg->css, nr_pages); |
60d3fd32 | 2353 | } |
127424c8 | 2354 | #endif /* !CONFIG_SLOB */ |
7ae1e1d0 | 2355 | |
ca3e0214 KH |
2356 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
2357 | ||
ca3e0214 KH |
2358 | /* |
2359 | * Because tail pages are not marked as "used", set it. We're under | |
a52633d8 | 2360 | * zone_lru_lock and migration entries setup in all page mappings. |
ca3e0214 | 2361 | */ |
e94c8a9c | 2362 | void mem_cgroup_split_huge_fixup(struct page *head) |
ca3e0214 | 2363 | { |
e94c8a9c | 2364 | int i; |
ca3e0214 | 2365 | |
3d37c4a9 KH |
2366 | if (mem_cgroup_disabled()) |
2367 | return; | |
b070e65c | 2368 | |
29833315 | 2369 | for (i = 1; i < HPAGE_PMD_NR; i++) |
1306a85a | 2370 | head[i].mem_cgroup = head->mem_cgroup; |
b9982f8d | 2371 | |
71cd3113 | 2372 | __this_cpu_sub(head->mem_cgroup->stat->count[MEMCG_RSS_HUGE], |
b070e65c | 2373 | HPAGE_PMD_NR); |
ca3e0214 | 2374 | } |
12d27107 | 2375 | #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
ca3e0214 | 2376 | |
c255a458 | 2377 | #ifdef CONFIG_MEMCG_SWAP |
0a31bc97 | 2378 | static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg, |
38d8b4e6 | 2379 | int nr_entries) |
d13d1443 | 2380 | { |
38d8b4e6 | 2381 | this_cpu_add(memcg->stat->count[MEMCG_SWAP], nr_entries); |
d13d1443 | 2382 | } |
02491447 DN |
2383 | |
2384 | /** | |
2385 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
2386 | * @entry: swap entry to be moved | |
2387 | * @from: mem_cgroup which the entry is moved from | |
2388 | * @to: mem_cgroup which the entry is moved to | |
2389 | * | |
2390 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
2391 | * as the mem_cgroup's id of @from. | |
2392 | * | |
2393 | * Returns 0 on success, -EINVAL on failure. | |
2394 | * | |
3e32cb2e | 2395 | * The caller must have charged to @to, IOW, called page_counter_charge() about |
02491447 DN |
2396 | * both res and memsw, and called css_get(). |
2397 | */ | |
2398 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 2399 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
2400 | { |
2401 | unsigned short old_id, new_id; | |
2402 | ||
34c00c31 LZ |
2403 | old_id = mem_cgroup_id(from); |
2404 | new_id = mem_cgroup_id(to); | |
02491447 DN |
2405 | |
2406 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
38d8b4e6 HY |
2407 | mem_cgroup_swap_statistics(from, -1); |
2408 | mem_cgroup_swap_statistics(to, 1); | |
02491447 DN |
2409 | return 0; |
2410 | } | |
2411 | return -EINVAL; | |
2412 | } | |
2413 | #else | |
2414 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 2415 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
2416 | { |
2417 | return -EINVAL; | |
2418 | } | |
8c7c6e34 | 2419 | #endif |
d13d1443 | 2420 | |
3e32cb2e | 2421 | static DEFINE_MUTEX(memcg_limit_mutex); |
f212ad7c | 2422 | |
d38d2a75 | 2423 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
3e32cb2e | 2424 | unsigned long limit) |
628f4235 | 2425 | { |
3e32cb2e JW |
2426 | unsigned long curusage; |
2427 | unsigned long oldusage; | |
2428 | bool enlarge = false; | |
81d39c20 | 2429 | int retry_count; |
3e32cb2e | 2430 | int ret; |
81d39c20 KH |
2431 | |
2432 | /* | |
2433 | * For keeping hierarchical_reclaim simple, how long we should retry | |
2434 | * is depends on callers. We set our retry-count to be function | |
2435 | * of # of children which we should visit in this loop. | |
2436 | */ | |
3e32cb2e JW |
2437 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * |
2438 | mem_cgroup_count_children(memcg); | |
81d39c20 | 2439 | |
3e32cb2e | 2440 | oldusage = page_counter_read(&memcg->memory); |
628f4235 | 2441 | |
3e32cb2e | 2442 | do { |
628f4235 KH |
2443 | if (signal_pending(current)) { |
2444 | ret = -EINTR; | |
2445 | break; | |
2446 | } | |
3e32cb2e JW |
2447 | |
2448 | mutex_lock(&memcg_limit_mutex); | |
2449 | if (limit > memcg->memsw.limit) { | |
2450 | mutex_unlock(&memcg_limit_mutex); | |
8c7c6e34 | 2451 | ret = -EINVAL; |
628f4235 KH |
2452 | break; |
2453 | } | |
3e32cb2e JW |
2454 | if (limit > memcg->memory.limit) |
2455 | enlarge = true; | |
2456 | ret = page_counter_limit(&memcg->memory, limit); | |
2457 | mutex_unlock(&memcg_limit_mutex); | |
8c7c6e34 KH |
2458 | |
2459 | if (!ret) | |
2460 | break; | |
2461 | ||
b70a2a21 JW |
2462 | try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, true); |
2463 | ||
3e32cb2e | 2464 | curusage = page_counter_read(&memcg->memory); |
81d39c20 | 2465 | /* Usage is reduced ? */ |
f894ffa8 | 2466 | if (curusage >= oldusage) |
81d39c20 KH |
2467 | retry_count--; |
2468 | else | |
2469 | oldusage = curusage; | |
3e32cb2e JW |
2470 | } while (retry_count); |
2471 | ||
3c11ecf4 KH |
2472 | if (!ret && enlarge) |
2473 | memcg_oom_recover(memcg); | |
14797e23 | 2474 | |
8c7c6e34 KH |
2475 | return ret; |
2476 | } | |
2477 | ||
338c8431 | 2478 | static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, |
3e32cb2e | 2479 | unsigned long limit) |
8c7c6e34 | 2480 | { |
3e32cb2e JW |
2481 | unsigned long curusage; |
2482 | unsigned long oldusage; | |
2483 | bool enlarge = false; | |
81d39c20 | 2484 | int retry_count; |
3e32cb2e | 2485 | int ret; |
8c7c6e34 | 2486 | |
81d39c20 | 2487 | /* see mem_cgroup_resize_res_limit */ |
3e32cb2e JW |
2488 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * |
2489 | mem_cgroup_count_children(memcg); | |
2490 | ||
2491 | oldusage = page_counter_read(&memcg->memsw); | |
2492 | ||
2493 | do { | |
8c7c6e34 KH |
2494 | if (signal_pending(current)) { |
2495 | ret = -EINTR; | |
2496 | break; | |
2497 | } | |
3e32cb2e JW |
2498 | |
2499 | mutex_lock(&memcg_limit_mutex); | |
2500 | if (limit < memcg->memory.limit) { | |
2501 | mutex_unlock(&memcg_limit_mutex); | |
8c7c6e34 | 2502 | ret = -EINVAL; |
8c7c6e34 KH |
2503 | break; |
2504 | } | |
3e32cb2e JW |
2505 | if (limit > memcg->memsw.limit) |
2506 | enlarge = true; | |
2507 | ret = page_counter_limit(&memcg->memsw, limit); | |
2508 | mutex_unlock(&memcg_limit_mutex); | |
8c7c6e34 KH |
2509 | |
2510 | if (!ret) | |
2511 | break; | |
2512 | ||
b70a2a21 JW |
2513 | try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, false); |
2514 | ||
3e32cb2e | 2515 | curusage = page_counter_read(&memcg->memsw); |
81d39c20 | 2516 | /* Usage is reduced ? */ |
8c7c6e34 | 2517 | if (curusage >= oldusage) |
628f4235 | 2518 | retry_count--; |
81d39c20 KH |
2519 | else |
2520 | oldusage = curusage; | |
3e32cb2e JW |
2521 | } while (retry_count); |
2522 | ||
3c11ecf4 KH |
2523 | if (!ret && enlarge) |
2524 | memcg_oom_recover(memcg); | |
3e32cb2e | 2525 | |
628f4235 KH |
2526 | return ret; |
2527 | } | |
2528 | ||
ef8f2327 | 2529 | unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, |
0608f43d AM |
2530 | gfp_t gfp_mask, |
2531 | unsigned long *total_scanned) | |
2532 | { | |
2533 | unsigned long nr_reclaimed = 0; | |
ef8f2327 | 2534 | struct mem_cgroup_per_node *mz, *next_mz = NULL; |
0608f43d AM |
2535 | unsigned long reclaimed; |
2536 | int loop = 0; | |
ef8f2327 | 2537 | struct mem_cgroup_tree_per_node *mctz; |
3e32cb2e | 2538 | unsigned long excess; |
0608f43d AM |
2539 | unsigned long nr_scanned; |
2540 | ||
2541 | if (order > 0) | |
2542 | return 0; | |
2543 | ||
ef8f2327 | 2544 | mctz = soft_limit_tree_node(pgdat->node_id); |
d6507ff5 MH |
2545 | |
2546 | /* | |
2547 | * Do not even bother to check the largest node if the root | |
2548 | * is empty. Do it lockless to prevent lock bouncing. Races | |
2549 | * are acceptable as soft limit is best effort anyway. | |
2550 | */ | |
bfc7228b | 2551 | if (!mctz || RB_EMPTY_ROOT(&mctz->rb_root)) |
d6507ff5 MH |
2552 | return 0; |
2553 | ||
0608f43d AM |
2554 | /* |
2555 | * This loop can run a while, specially if mem_cgroup's continuously | |
2556 | * keep exceeding their soft limit and putting the system under | |
2557 | * pressure | |
2558 | */ | |
2559 | do { | |
2560 | if (next_mz) | |
2561 | mz = next_mz; | |
2562 | else | |
2563 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
2564 | if (!mz) | |
2565 | break; | |
2566 | ||
2567 | nr_scanned = 0; | |
ef8f2327 | 2568 | reclaimed = mem_cgroup_soft_reclaim(mz->memcg, pgdat, |
0608f43d AM |
2569 | gfp_mask, &nr_scanned); |
2570 | nr_reclaimed += reclaimed; | |
2571 | *total_scanned += nr_scanned; | |
0a31bc97 | 2572 | spin_lock_irq(&mctz->lock); |
bc2f2e7f | 2573 | __mem_cgroup_remove_exceeded(mz, mctz); |
0608f43d AM |
2574 | |
2575 | /* | |
2576 | * If we failed to reclaim anything from this memory cgroup | |
2577 | * it is time to move on to the next cgroup | |
2578 | */ | |
2579 | next_mz = NULL; | |
bc2f2e7f VD |
2580 | if (!reclaimed) |
2581 | next_mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
2582 | ||
3e32cb2e | 2583 | excess = soft_limit_excess(mz->memcg); |
0608f43d AM |
2584 | /* |
2585 | * One school of thought says that we should not add | |
2586 | * back the node to the tree if reclaim returns 0. | |
2587 | * But our reclaim could return 0, simply because due | |
2588 | * to priority we are exposing a smaller subset of | |
2589 | * memory to reclaim from. Consider this as a longer | |
2590 | * term TODO. | |
2591 | */ | |
2592 | /* If excess == 0, no tree ops */ | |
cf2c8127 | 2593 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 2594 | spin_unlock_irq(&mctz->lock); |
0608f43d AM |
2595 | css_put(&mz->memcg->css); |
2596 | loop++; | |
2597 | /* | |
2598 | * Could not reclaim anything and there are no more | |
2599 | * mem cgroups to try or we seem to be looping without | |
2600 | * reclaiming anything. | |
2601 | */ | |
2602 | if (!nr_reclaimed && | |
2603 | (next_mz == NULL || | |
2604 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
2605 | break; | |
2606 | } while (!nr_reclaimed); | |
2607 | if (next_mz) | |
2608 | css_put(&next_mz->memcg->css); | |
2609 | return nr_reclaimed; | |
2610 | } | |
2611 | ||
ea280e7b TH |
2612 | /* |
2613 | * Test whether @memcg has children, dead or alive. Note that this | |
2614 | * function doesn't care whether @memcg has use_hierarchy enabled and | |
2615 | * returns %true if there are child csses according to the cgroup | |
2616 | * hierarchy. Testing use_hierarchy is the caller's responsiblity. | |
2617 | */ | |
b5f99b53 GC |
2618 | static inline bool memcg_has_children(struct mem_cgroup *memcg) |
2619 | { | |
ea280e7b TH |
2620 | bool ret; |
2621 | ||
ea280e7b TH |
2622 | rcu_read_lock(); |
2623 | ret = css_next_child(NULL, &memcg->css); | |
2624 | rcu_read_unlock(); | |
2625 | return ret; | |
b5f99b53 GC |
2626 | } |
2627 | ||
c26251f9 | 2628 | /* |
51038171 | 2629 | * Reclaims as many pages from the given memcg as possible. |
c26251f9 MH |
2630 | * |
2631 | * Caller is responsible for holding css reference for memcg. | |
2632 | */ | |
2633 | static int mem_cgroup_force_empty(struct mem_cgroup *memcg) | |
2634 | { | |
2635 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
c26251f9 | 2636 | |
c1e862c1 KH |
2637 | /* we call try-to-free pages for make this cgroup empty */ |
2638 | lru_add_drain_all(); | |
f817ed48 | 2639 | /* try to free all pages in this cgroup */ |
3e32cb2e | 2640 | while (nr_retries && page_counter_read(&memcg->memory)) { |
f817ed48 | 2641 | int progress; |
c1e862c1 | 2642 | |
c26251f9 MH |
2643 | if (signal_pending(current)) |
2644 | return -EINTR; | |
2645 | ||
b70a2a21 JW |
2646 | progress = try_to_free_mem_cgroup_pages(memcg, 1, |
2647 | GFP_KERNEL, true); | |
c1e862c1 | 2648 | if (!progress) { |
f817ed48 | 2649 | nr_retries--; |
c1e862c1 | 2650 | /* maybe some writeback is necessary */ |
8aa7e847 | 2651 | congestion_wait(BLK_RW_ASYNC, HZ/10); |
c1e862c1 | 2652 | } |
f817ed48 KH |
2653 | |
2654 | } | |
ab5196c2 MH |
2655 | |
2656 | return 0; | |
cc847582 KH |
2657 | } |
2658 | ||
6770c64e TH |
2659 | static ssize_t mem_cgroup_force_empty_write(struct kernfs_open_file *of, |
2660 | char *buf, size_t nbytes, | |
2661 | loff_t off) | |
c1e862c1 | 2662 | { |
6770c64e | 2663 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
c26251f9 | 2664 | |
d8423011 MH |
2665 | if (mem_cgroup_is_root(memcg)) |
2666 | return -EINVAL; | |
6770c64e | 2667 | return mem_cgroup_force_empty(memcg) ?: nbytes; |
c1e862c1 KH |
2668 | } |
2669 | ||
182446d0 TH |
2670 | static u64 mem_cgroup_hierarchy_read(struct cgroup_subsys_state *css, |
2671 | struct cftype *cft) | |
18f59ea7 | 2672 | { |
182446d0 | 2673 | return mem_cgroup_from_css(css)->use_hierarchy; |
18f59ea7 BS |
2674 | } |
2675 | ||
182446d0 TH |
2676 | static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css, |
2677 | struct cftype *cft, u64 val) | |
18f59ea7 BS |
2678 | { |
2679 | int retval = 0; | |
182446d0 | 2680 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
5c9d535b | 2681 | struct mem_cgroup *parent_memcg = mem_cgroup_from_css(memcg->css.parent); |
18f59ea7 | 2682 | |
567fb435 | 2683 | if (memcg->use_hierarchy == val) |
0b8f73e1 | 2684 | return 0; |
567fb435 | 2685 | |
18f59ea7 | 2686 | /* |
af901ca1 | 2687 | * If parent's use_hierarchy is set, we can't make any modifications |
18f59ea7 BS |
2688 | * in the child subtrees. If it is unset, then the change can |
2689 | * occur, provided the current cgroup has no children. | |
2690 | * | |
2691 | * For the root cgroup, parent_mem is NULL, we allow value to be | |
2692 | * set if there are no children. | |
2693 | */ | |
c0ff4b85 | 2694 | if ((!parent_memcg || !parent_memcg->use_hierarchy) && |
18f59ea7 | 2695 | (val == 1 || val == 0)) { |
ea280e7b | 2696 | if (!memcg_has_children(memcg)) |
c0ff4b85 | 2697 | memcg->use_hierarchy = val; |
18f59ea7 BS |
2698 | else |
2699 | retval = -EBUSY; | |
2700 | } else | |
2701 | retval = -EINVAL; | |
567fb435 | 2702 | |
18f59ea7 BS |
2703 | return retval; |
2704 | } | |
2705 | ||
72b54e73 | 2706 | static void tree_stat(struct mem_cgroup *memcg, unsigned long *stat) |
ce00a967 JW |
2707 | { |
2708 | struct mem_cgroup *iter; | |
72b54e73 | 2709 | int i; |
ce00a967 | 2710 | |
72b54e73 | 2711 | memset(stat, 0, sizeof(*stat) * MEMCG_NR_STAT); |
ce00a967 | 2712 | |
72b54e73 VD |
2713 | for_each_mem_cgroup_tree(iter, memcg) { |
2714 | for (i = 0; i < MEMCG_NR_STAT; i++) | |
ccda7f43 | 2715 | stat[i] += memcg_page_state(iter, i); |
72b54e73 | 2716 | } |
ce00a967 JW |
2717 | } |
2718 | ||
72b54e73 | 2719 | static void tree_events(struct mem_cgroup *memcg, unsigned long *events) |
587d9f72 JW |
2720 | { |
2721 | struct mem_cgroup *iter; | |
72b54e73 | 2722 | int i; |
587d9f72 | 2723 | |
72b54e73 | 2724 | memset(events, 0, sizeof(*events) * MEMCG_NR_EVENTS); |
587d9f72 | 2725 | |
72b54e73 VD |
2726 | for_each_mem_cgroup_tree(iter, memcg) { |
2727 | for (i = 0; i < MEMCG_NR_EVENTS; i++) | |
ccda7f43 | 2728 | events[i] += memcg_sum_events(iter, i); |
72b54e73 | 2729 | } |
587d9f72 JW |
2730 | } |
2731 | ||
6f646156 | 2732 | static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) |
ce00a967 | 2733 | { |
72b54e73 | 2734 | unsigned long val = 0; |
ce00a967 | 2735 | |
3e32cb2e | 2736 | if (mem_cgroup_is_root(memcg)) { |
72b54e73 VD |
2737 | struct mem_cgroup *iter; |
2738 | ||
2739 | for_each_mem_cgroup_tree(iter, memcg) { | |
ccda7f43 JW |
2740 | val += memcg_page_state(iter, MEMCG_CACHE); |
2741 | val += memcg_page_state(iter, MEMCG_RSS); | |
72b54e73 | 2742 | if (swap) |
ccda7f43 | 2743 | val += memcg_page_state(iter, MEMCG_SWAP); |
72b54e73 | 2744 | } |
3e32cb2e | 2745 | } else { |
ce00a967 | 2746 | if (!swap) |
3e32cb2e | 2747 | val = page_counter_read(&memcg->memory); |
ce00a967 | 2748 | else |
3e32cb2e | 2749 | val = page_counter_read(&memcg->memsw); |
ce00a967 | 2750 | } |
c12176d3 | 2751 | return val; |
ce00a967 JW |
2752 | } |
2753 | ||
3e32cb2e JW |
2754 | enum { |
2755 | RES_USAGE, | |
2756 | RES_LIMIT, | |
2757 | RES_MAX_USAGE, | |
2758 | RES_FAILCNT, | |
2759 | RES_SOFT_LIMIT, | |
2760 | }; | |
ce00a967 | 2761 | |
791badbd | 2762 | static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css, |
05b84301 | 2763 | struct cftype *cft) |
8cdea7c0 | 2764 | { |
182446d0 | 2765 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3e32cb2e | 2766 | struct page_counter *counter; |
af36f906 | 2767 | |
3e32cb2e | 2768 | switch (MEMFILE_TYPE(cft->private)) { |
8c7c6e34 | 2769 | case _MEM: |
3e32cb2e JW |
2770 | counter = &memcg->memory; |
2771 | break; | |
8c7c6e34 | 2772 | case _MEMSWAP: |
3e32cb2e JW |
2773 | counter = &memcg->memsw; |
2774 | break; | |
510fc4e1 | 2775 | case _KMEM: |
3e32cb2e | 2776 | counter = &memcg->kmem; |
510fc4e1 | 2777 | break; |
d55f90bf | 2778 | case _TCP: |
0db15298 | 2779 | counter = &memcg->tcpmem; |
d55f90bf | 2780 | break; |
8c7c6e34 KH |
2781 | default: |
2782 | BUG(); | |
8c7c6e34 | 2783 | } |
3e32cb2e JW |
2784 | |
2785 | switch (MEMFILE_ATTR(cft->private)) { | |
2786 | case RES_USAGE: | |
2787 | if (counter == &memcg->memory) | |
c12176d3 | 2788 | return (u64)mem_cgroup_usage(memcg, false) * PAGE_SIZE; |
3e32cb2e | 2789 | if (counter == &memcg->memsw) |
c12176d3 | 2790 | return (u64)mem_cgroup_usage(memcg, true) * PAGE_SIZE; |
3e32cb2e JW |
2791 | return (u64)page_counter_read(counter) * PAGE_SIZE; |
2792 | case RES_LIMIT: | |
2793 | return (u64)counter->limit * PAGE_SIZE; | |
2794 | case RES_MAX_USAGE: | |
2795 | return (u64)counter->watermark * PAGE_SIZE; | |
2796 | case RES_FAILCNT: | |
2797 | return counter->failcnt; | |
2798 | case RES_SOFT_LIMIT: | |
2799 | return (u64)memcg->soft_limit * PAGE_SIZE; | |
2800 | default: | |
2801 | BUG(); | |
2802 | } | |
8cdea7c0 | 2803 | } |
510fc4e1 | 2804 | |
127424c8 | 2805 | #ifndef CONFIG_SLOB |
567e9ab2 | 2806 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
d6441637 | 2807 | { |
d6441637 VD |
2808 | int memcg_id; |
2809 | ||
b313aeee VD |
2810 | if (cgroup_memory_nokmem) |
2811 | return 0; | |
2812 | ||
2a4db7eb | 2813 | BUG_ON(memcg->kmemcg_id >= 0); |
567e9ab2 | 2814 | BUG_ON(memcg->kmem_state); |
d6441637 | 2815 | |
f3bb3043 | 2816 | memcg_id = memcg_alloc_cache_id(); |
0b8f73e1 JW |
2817 | if (memcg_id < 0) |
2818 | return memcg_id; | |
d6441637 | 2819 | |
ef12947c | 2820 | static_branch_inc(&memcg_kmem_enabled_key); |
d6441637 | 2821 | /* |
567e9ab2 | 2822 | * A memory cgroup is considered kmem-online as soon as it gets |
900a38f0 | 2823 | * kmemcg_id. Setting the id after enabling static branching will |
d6441637 VD |
2824 | * guarantee no one starts accounting before all call sites are |
2825 | * patched. | |
2826 | */ | |
900a38f0 | 2827 | memcg->kmemcg_id = memcg_id; |
567e9ab2 | 2828 | memcg->kmem_state = KMEM_ONLINE; |
bc2791f8 | 2829 | INIT_LIST_HEAD(&memcg->kmem_caches); |
0b8f73e1 JW |
2830 | |
2831 | return 0; | |
d6441637 VD |
2832 | } |
2833 | ||
8e0a8912 JW |
2834 | static void memcg_offline_kmem(struct mem_cgroup *memcg) |
2835 | { | |
2836 | struct cgroup_subsys_state *css; | |
2837 | struct mem_cgroup *parent, *child; | |
2838 | int kmemcg_id; | |
2839 | ||
2840 | if (memcg->kmem_state != KMEM_ONLINE) | |
2841 | return; | |
2842 | /* | |
2843 | * Clear the online state before clearing memcg_caches array | |
2844 | * entries. The slab_mutex in memcg_deactivate_kmem_caches() | |
2845 | * guarantees that no cache will be created for this cgroup | |
2846 | * after we are done (see memcg_create_kmem_cache()). | |
2847 | */ | |
2848 | memcg->kmem_state = KMEM_ALLOCATED; | |
2849 | ||
2850 | memcg_deactivate_kmem_caches(memcg); | |
2851 | ||
2852 | kmemcg_id = memcg->kmemcg_id; | |
2853 | BUG_ON(kmemcg_id < 0); | |
2854 | ||
2855 | parent = parent_mem_cgroup(memcg); | |
2856 | if (!parent) | |
2857 | parent = root_mem_cgroup; | |
2858 | ||
2859 | /* | |
2860 | * Change kmemcg_id of this cgroup and all its descendants to the | |
2861 | * parent's id, and then move all entries from this cgroup's list_lrus | |
2862 | * to ones of the parent. After we have finished, all list_lrus | |
2863 | * corresponding to this cgroup are guaranteed to remain empty. The | |
2864 | * ordering is imposed by list_lru_node->lock taken by | |
2865 | * memcg_drain_all_list_lrus(). | |
2866 | */ | |
3a06bb78 | 2867 | rcu_read_lock(); /* can be called from css_free w/o cgroup_mutex */ |
8e0a8912 JW |
2868 | css_for_each_descendant_pre(css, &memcg->css) { |
2869 | child = mem_cgroup_from_css(css); | |
2870 | BUG_ON(child->kmemcg_id != kmemcg_id); | |
2871 | child->kmemcg_id = parent->kmemcg_id; | |
2872 | if (!memcg->use_hierarchy) | |
2873 | break; | |
2874 | } | |
3a06bb78 TH |
2875 | rcu_read_unlock(); |
2876 | ||
8e0a8912 JW |
2877 | memcg_drain_all_list_lrus(kmemcg_id, parent->kmemcg_id); |
2878 | ||
2879 | memcg_free_cache_id(kmemcg_id); | |
2880 | } | |
2881 | ||
2882 | static void memcg_free_kmem(struct mem_cgroup *memcg) | |
2883 | { | |
0b8f73e1 JW |
2884 | /* css_alloc() failed, offlining didn't happen */ |
2885 | if (unlikely(memcg->kmem_state == KMEM_ONLINE)) | |
2886 | memcg_offline_kmem(memcg); | |
2887 | ||
8e0a8912 JW |
2888 | if (memcg->kmem_state == KMEM_ALLOCATED) { |
2889 | memcg_destroy_kmem_caches(memcg); | |
2890 | static_branch_dec(&memcg_kmem_enabled_key); | |
2891 | WARN_ON(page_counter_read(&memcg->kmem)); | |
2892 | } | |
8e0a8912 | 2893 | } |
d6441637 | 2894 | #else |
0b8f73e1 | 2895 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
127424c8 JW |
2896 | { |
2897 | return 0; | |
2898 | } | |
2899 | static void memcg_offline_kmem(struct mem_cgroup *memcg) | |
2900 | { | |
2901 | } | |
2902 | static void memcg_free_kmem(struct mem_cgroup *memcg) | |
2903 | { | |
2904 | } | |
2905 | #endif /* !CONFIG_SLOB */ | |
2906 | ||
d6441637 | 2907 | static int memcg_update_kmem_limit(struct mem_cgroup *memcg, |
3e32cb2e | 2908 | unsigned long limit) |
d6441637 | 2909 | { |
b313aeee | 2910 | int ret; |
127424c8 JW |
2911 | |
2912 | mutex_lock(&memcg_limit_mutex); | |
127424c8 | 2913 | ret = page_counter_limit(&memcg->kmem, limit); |
127424c8 JW |
2914 | mutex_unlock(&memcg_limit_mutex); |
2915 | return ret; | |
d6441637 | 2916 | } |
510fc4e1 | 2917 | |
d55f90bf VD |
2918 | static int memcg_update_tcp_limit(struct mem_cgroup *memcg, unsigned long limit) |
2919 | { | |
2920 | int ret; | |
2921 | ||
2922 | mutex_lock(&memcg_limit_mutex); | |
2923 | ||
0db15298 | 2924 | ret = page_counter_limit(&memcg->tcpmem, limit); |
d55f90bf VD |
2925 | if (ret) |
2926 | goto out; | |
2927 | ||
0db15298 | 2928 | if (!memcg->tcpmem_active) { |
d55f90bf VD |
2929 | /* |
2930 | * The active flag needs to be written after the static_key | |
2931 | * update. This is what guarantees that the socket activation | |
2d758073 JW |
2932 | * function is the last one to run. See mem_cgroup_sk_alloc() |
2933 | * for details, and note that we don't mark any socket as | |
2934 | * belonging to this memcg until that flag is up. | |
d55f90bf VD |
2935 | * |
2936 | * We need to do this, because static_keys will span multiple | |
2937 | * sites, but we can't control their order. If we mark a socket | |
2938 | * as accounted, but the accounting functions are not patched in | |
2939 | * yet, we'll lose accounting. | |
2940 | * | |
2d758073 | 2941 | * We never race with the readers in mem_cgroup_sk_alloc(), |
d55f90bf VD |
2942 | * because when this value change, the code to process it is not |
2943 | * patched in yet. | |
2944 | */ | |
2945 | static_branch_inc(&memcg_sockets_enabled_key); | |
0db15298 | 2946 | memcg->tcpmem_active = true; |
d55f90bf VD |
2947 | } |
2948 | out: | |
2949 | mutex_unlock(&memcg_limit_mutex); | |
2950 | return ret; | |
2951 | } | |
d55f90bf | 2952 | |
628f4235 KH |
2953 | /* |
2954 | * The user of this function is... | |
2955 | * RES_LIMIT. | |
2956 | */ | |
451af504 TH |
2957 | static ssize_t mem_cgroup_write(struct kernfs_open_file *of, |
2958 | char *buf, size_t nbytes, loff_t off) | |
8cdea7c0 | 2959 | { |
451af504 | 2960 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 2961 | unsigned long nr_pages; |
628f4235 KH |
2962 | int ret; |
2963 | ||
451af504 | 2964 | buf = strstrip(buf); |
650c5e56 | 2965 | ret = page_counter_memparse(buf, "-1", &nr_pages); |
3e32cb2e JW |
2966 | if (ret) |
2967 | return ret; | |
af36f906 | 2968 | |
3e32cb2e | 2969 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
628f4235 | 2970 | case RES_LIMIT: |
4b3bde4c BS |
2971 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
2972 | ret = -EINVAL; | |
2973 | break; | |
2974 | } | |
3e32cb2e JW |
2975 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
2976 | case _MEM: | |
2977 | ret = mem_cgroup_resize_limit(memcg, nr_pages); | |
8c7c6e34 | 2978 | break; |
3e32cb2e JW |
2979 | case _MEMSWAP: |
2980 | ret = mem_cgroup_resize_memsw_limit(memcg, nr_pages); | |
296c81d8 | 2981 | break; |
3e32cb2e JW |
2982 | case _KMEM: |
2983 | ret = memcg_update_kmem_limit(memcg, nr_pages); | |
2984 | break; | |
d55f90bf VD |
2985 | case _TCP: |
2986 | ret = memcg_update_tcp_limit(memcg, nr_pages); | |
2987 | break; | |
3e32cb2e | 2988 | } |
296c81d8 | 2989 | break; |
3e32cb2e JW |
2990 | case RES_SOFT_LIMIT: |
2991 | memcg->soft_limit = nr_pages; | |
2992 | ret = 0; | |
628f4235 KH |
2993 | break; |
2994 | } | |
451af504 | 2995 | return ret ?: nbytes; |
8cdea7c0 BS |
2996 | } |
2997 | ||
6770c64e TH |
2998 | static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf, |
2999 | size_t nbytes, loff_t off) | |
c84872e1 | 3000 | { |
6770c64e | 3001 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 3002 | struct page_counter *counter; |
c84872e1 | 3003 | |
3e32cb2e JW |
3004 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
3005 | case _MEM: | |
3006 | counter = &memcg->memory; | |
3007 | break; | |
3008 | case _MEMSWAP: | |
3009 | counter = &memcg->memsw; | |
3010 | break; | |
3011 | case _KMEM: | |
3012 | counter = &memcg->kmem; | |
3013 | break; | |
d55f90bf | 3014 | case _TCP: |
0db15298 | 3015 | counter = &memcg->tcpmem; |
d55f90bf | 3016 | break; |
3e32cb2e JW |
3017 | default: |
3018 | BUG(); | |
3019 | } | |
af36f906 | 3020 | |
3e32cb2e | 3021 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
29f2a4da | 3022 | case RES_MAX_USAGE: |
3e32cb2e | 3023 | page_counter_reset_watermark(counter); |
29f2a4da PE |
3024 | break; |
3025 | case RES_FAILCNT: | |
3e32cb2e | 3026 | counter->failcnt = 0; |
29f2a4da | 3027 | break; |
3e32cb2e JW |
3028 | default: |
3029 | BUG(); | |
29f2a4da | 3030 | } |
f64c3f54 | 3031 | |
6770c64e | 3032 | return nbytes; |
c84872e1 PE |
3033 | } |
3034 | ||
182446d0 | 3035 | static u64 mem_cgroup_move_charge_read(struct cgroup_subsys_state *css, |
7dc74be0 DN |
3036 | struct cftype *cft) |
3037 | { | |
182446d0 | 3038 | return mem_cgroup_from_css(css)->move_charge_at_immigrate; |
7dc74be0 DN |
3039 | } |
3040 | ||
02491447 | 3041 | #ifdef CONFIG_MMU |
182446d0 | 3042 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
7dc74be0 DN |
3043 | struct cftype *cft, u64 val) |
3044 | { | |
182446d0 | 3045 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
7dc74be0 | 3046 | |
1dfab5ab | 3047 | if (val & ~MOVE_MASK) |
7dc74be0 | 3048 | return -EINVAL; |
ee5e8472 | 3049 | |
7dc74be0 | 3050 | /* |
ee5e8472 GC |
3051 | * No kind of locking is needed in here, because ->can_attach() will |
3052 | * check this value once in the beginning of the process, and then carry | |
3053 | * on with stale data. This means that changes to this value will only | |
3054 | * affect task migrations starting after the change. | |
7dc74be0 | 3055 | */ |
c0ff4b85 | 3056 | memcg->move_charge_at_immigrate = val; |
7dc74be0 DN |
3057 | return 0; |
3058 | } | |
02491447 | 3059 | #else |
182446d0 | 3060 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
02491447 DN |
3061 | struct cftype *cft, u64 val) |
3062 | { | |
3063 | return -ENOSYS; | |
3064 | } | |
3065 | #endif | |
7dc74be0 | 3066 | |
406eb0c9 | 3067 | #ifdef CONFIG_NUMA |
2da8ca82 | 3068 | static int memcg_numa_stat_show(struct seq_file *m, void *v) |
406eb0c9 | 3069 | { |
25485de6 GT |
3070 | struct numa_stat { |
3071 | const char *name; | |
3072 | unsigned int lru_mask; | |
3073 | }; | |
3074 | ||
3075 | static const struct numa_stat stats[] = { | |
3076 | { "total", LRU_ALL }, | |
3077 | { "file", LRU_ALL_FILE }, | |
3078 | { "anon", LRU_ALL_ANON }, | |
3079 | { "unevictable", BIT(LRU_UNEVICTABLE) }, | |
3080 | }; | |
3081 | const struct numa_stat *stat; | |
406eb0c9 | 3082 | int nid; |
25485de6 | 3083 | unsigned long nr; |
2da8ca82 | 3084 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); |
406eb0c9 | 3085 | |
25485de6 GT |
3086 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
3087 | nr = mem_cgroup_nr_lru_pages(memcg, stat->lru_mask); | |
3088 | seq_printf(m, "%s=%lu", stat->name, nr); | |
3089 | for_each_node_state(nid, N_MEMORY) { | |
3090 | nr = mem_cgroup_node_nr_lru_pages(memcg, nid, | |
3091 | stat->lru_mask); | |
3092 | seq_printf(m, " N%d=%lu", nid, nr); | |
3093 | } | |
3094 | seq_putc(m, '\n'); | |
406eb0c9 | 3095 | } |
406eb0c9 | 3096 | |
071aee13 YH |
3097 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
3098 | struct mem_cgroup *iter; | |
3099 | ||
3100 | nr = 0; | |
3101 | for_each_mem_cgroup_tree(iter, memcg) | |
3102 | nr += mem_cgroup_nr_lru_pages(iter, stat->lru_mask); | |
3103 | seq_printf(m, "hierarchical_%s=%lu", stat->name, nr); | |
3104 | for_each_node_state(nid, N_MEMORY) { | |
3105 | nr = 0; | |
3106 | for_each_mem_cgroup_tree(iter, memcg) | |
3107 | nr += mem_cgroup_node_nr_lru_pages( | |
3108 | iter, nid, stat->lru_mask); | |
3109 | seq_printf(m, " N%d=%lu", nid, nr); | |
3110 | } | |
3111 | seq_putc(m, '\n'); | |
406eb0c9 | 3112 | } |
406eb0c9 | 3113 | |
406eb0c9 YH |
3114 | return 0; |
3115 | } | |
3116 | #endif /* CONFIG_NUMA */ | |
3117 | ||
df0e53d0 JW |
3118 | /* Universal VM events cgroup1 shows, original sort order */ |
3119 | unsigned int memcg1_events[] = { | |
3120 | PGPGIN, | |
3121 | PGPGOUT, | |
3122 | PGFAULT, | |
3123 | PGMAJFAULT, | |
3124 | }; | |
3125 | ||
3126 | static const char *const memcg1_event_names[] = { | |
3127 | "pgpgin", | |
3128 | "pgpgout", | |
3129 | "pgfault", | |
3130 | "pgmajfault", | |
3131 | }; | |
3132 | ||
2da8ca82 | 3133 | static int memcg_stat_show(struct seq_file *m, void *v) |
d2ceb9b7 | 3134 | { |
2da8ca82 | 3135 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); |
3e32cb2e | 3136 | unsigned long memory, memsw; |
af7c4b0e JW |
3137 | struct mem_cgroup *mi; |
3138 | unsigned int i; | |
406eb0c9 | 3139 | |
71cd3113 | 3140 | BUILD_BUG_ON(ARRAY_SIZE(memcg1_stat_names) != ARRAY_SIZE(memcg1_stats)); |
70bc068c RS |
3141 | BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_lru_names) != NR_LRU_LISTS); |
3142 | ||
71cd3113 JW |
3143 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
3144 | if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account()) | |
1dd3a273 | 3145 | continue; |
71cd3113 | 3146 | seq_printf(m, "%s %lu\n", memcg1_stat_names[i], |
ccda7f43 | 3147 | memcg_page_state(memcg, memcg1_stats[i]) * |
71cd3113 | 3148 | PAGE_SIZE); |
1dd3a273 | 3149 | } |
7b854121 | 3150 | |
df0e53d0 JW |
3151 | for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) |
3152 | seq_printf(m, "%s %lu\n", memcg1_event_names[i], | |
ccda7f43 | 3153 | memcg_sum_events(memcg, memcg1_events[i])); |
af7c4b0e JW |
3154 | |
3155 | for (i = 0; i < NR_LRU_LISTS; i++) | |
3156 | seq_printf(m, "%s %lu\n", mem_cgroup_lru_names[i], | |
3157 | mem_cgroup_nr_lru_pages(memcg, BIT(i)) * PAGE_SIZE); | |
3158 | ||
14067bb3 | 3159 | /* Hierarchical information */ |
3e32cb2e JW |
3160 | memory = memsw = PAGE_COUNTER_MAX; |
3161 | for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) { | |
3162 | memory = min(memory, mi->memory.limit); | |
3163 | memsw = min(memsw, mi->memsw.limit); | |
fee7b548 | 3164 | } |
3e32cb2e JW |
3165 | seq_printf(m, "hierarchical_memory_limit %llu\n", |
3166 | (u64)memory * PAGE_SIZE); | |
7941d214 | 3167 | if (do_memsw_account()) |
3e32cb2e JW |
3168 | seq_printf(m, "hierarchical_memsw_limit %llu\n", |
3169 | (u64)memsw * PAGE_SIZE); | |
7f016ee8 | 3170 | |
71cd3113 | 3171 | for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) { |
484ebb3b | 3172 | unsigned long long val = 0; |
af7c4b0e | 3173 | |
71cd3113 | 3174 | if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account()) |
1dd3a273 | 3175 | continue; |
af7c4b0e | 3176 | for_each_mem_cgroup_tree(mi, memcg) |
ccda7f43 | 3177 | val += memcg_page_state(mi, memcg1_stats[i]) * |
71cd3113 JW |
3178 | PAGE_SIZE; |
3179 | seq_printf(m, "total_%s %llu\n", memcg1_stat_names[i], val); | |
af7c4b0e JW |
3180 | } |
3181 | ||
df0e53d0 | 3182 | for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) { |
af7c4b0e JW |
3183 | unsigned long long val = 0; |
3184 | ||
3185 | for_each_mem_cgroup_tree(mi, memcg) | |
ccda7f43 | 3186 | val += memcg_sum_events(mi, memcg1_events[i]); |
df0e53d0 | 3187 | seq_printf(m, "total_%s %llu\n", memcg1_event_names[i], val); |
af7c4b0e JW |
3188 | } |
3189 | ||
3190 | for (i = 0; i < NR_LRU_LISTS; i++) { | |
3191 | unsigned long long val = 0; | |
3192 | ||
3193 | for_each_mem_cgroup_tree(mi, memcg) | |
3194 | val += mem_cgroup_nr_lru_pages(mi, BIT(i)) * PAGE_SIZE; | |
3195 | seq_printf(m, "total_%s %llu\n", mem_cgroup_lru_names[i], val); | |
1dd3a273 | 3196 | } |
14067bb3 | 3197 | |
7f016ee8 | 3198 | #ifdef CONFIG_DEBUG_VM |
7f016ee8 | 3199 | { |
ef8f2327 MG |
3200 | pg_data_t *pgdat; |
3201 | struct mem_cgroup_per_node *mz; | |
89abfab1 | 3202 | struct zone_reclaim_stat *rstat; |
7f016ee8 KM |
3203 | unsigned long recent_rotated[2] = {0, 0}; |
3204 | unsigned long recent_scanned[2] = {0, 0}; | |
3205 | ||
ef8f2327 MG |
3206 | for_each_online_pgdat(pgdat) { |
3207 | mz = mem_cgroup_nodeinfo(memcg, pgdat->node_id); | |
3208 | rstat = &mz->lruvec.reclaim_stat; | |
7f016ee8 | 3209 | |
ef8f2327 MG |
3210 | recent_rotated[0] += rstat->recent_rotated[0]; |
3211 | recent_rotated[1] += rstat->recent_rotated[1]; | |
3212 | recent_scanned[0] += rstat->recent_scanned[0]; | |
3213 | recent_scanned[1] += rstat->recent_scanned[1]; | |
3214 | } | |
78ccf5b5 JW |
3215 | seq_printf(m, "recent_rotated_anon %lu\n", recent_rotated[0]); |
3216 | seq_printf(m, "recent_rotated_file %lu\n", recent_rotated[1]); | |
3217 | seq_printf(m, "recent_scanned_anon %lu\n", recent_scanned[0]); | |
3218 | seq_printf(m, "recent_scanned_file %lu\n", recent_scanned[1]); | |
7f016ee8 KM |
3219 | } |
3220 | #endif | |
3221 | ||
d2ceb9b7 KH |
3222 | return 0; |
3223 | } | |
3224 | ||
182446d0 TH |
3225 | static u64 mem_cgroup_swappiness_read(struct cgroup_subsys_state *css, |
3226 | struct cftype *cft) | |
a7885eb8 | 3227 | { |
182446d0 | 3228 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 3229 | |
1f4c025b | 3230 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
3231 | } |
3232 | ||
182446d0 TH |
3233 | static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, |
3234 | struct cftype *cft, u64 val) | |
a7885eb8 | 3235 | { |
182446d0 | 3236 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 3237 | |
3dae7fec | 3238 | if (val > 100) |
a7885eb8 KM |
3239 | return -EINVAL; |
3240 | ||
14208b0e | 3241 | if (css->parent) |
3dae7fec JW |
3242 | memcg->swappiness = val; |
3243 | else | |
3244 | vm_swappiness = val; | |
068b38c1 | 3245 | |
a7885eb8 KM |
3246 | return 0; |
3247 | } | |
3248 | ||
2e72b634 KS |
3249 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
3250 | { | |
3251 | struct mem_cgroup_threshold_ary *t; | |
3e32cb2e | 3252 | unsigned long usage; |
2e72b634 KS |
3253 | int i; |
3254 | ||
3255 | rcu_read_lock(); | |
3256 | if (!swap) | |
2c488db2 | 3257 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 3258 | else |
2c488db2 | 3259 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
3260 | |
3261 | if (!t) | |
3262 | goto unlock; | |
3263 | ||
ce00a967 | 3264 | usage = mem_cgroup_usage(memcg, swap); |
2e72b634 KS |
3265 | |
3266 | /* | |
748dad36 | 3267 | * current_threshold points to threshold just below or equal to usage. |
2e72b634 KS |
3268 | * If it's not true, a threshold was crossed after last |
3269 | * call of __mem_cgroup_threshold(). | |
3270 | */ | |
5407a562 | 3271 | i = t->current_threshold; |
2e72b634 KS |
3272 | |
3273 | /* | |
3274 | * Iterate backward over array of thresholds starting from | |
3275 | * current_threshold and check if a threshold is crossed. | |
3276 | * If none of thresholds below usage is crossed, we read | |
3277 | * only one element of the array here. | |
3278 | */ | |
3279 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
3280 | eventfd_signal(t->entries[i].eventfd, 1); | |
3281 | ||
3282 | /* i = current_threshold + 1 */ | |
3283 | i++; | |
3284 | ||
3285 | /* | |
3286 | * Iterate forward over array of thresholds starting from | |
3287 | * current_threshold+1 and check if a threshold is crossed. | |
3288 | * If none of thresholds above usage is crossed, we read | |
3289 | * only one element of the array here. | |
3290 | */ | |
3291 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
3292 | eventfd_signal(t->entries[i].eventfd, 1); | |
3293 | ||
3294 | /* Update current_threshold */ | |
5407a562 | 3295 | t->current_threshold = i - 1; |
2e72b634 KS |
3296 | unlock: |
3297 | rcu_read_unlock(); | |
3298 | } | |
3299 | ||
3300 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
3301 | { | |
ad4ca5f4 KS |
3302 | while (memcg) { |
3303 | __mem_cgroup_threshold(memcg, false); | |
7941d214 | 3304 | if (do_memsw_account()) |
ad4ca5f4 KS |
3305 | __mem_cgroup_threshold(memcg, true); |
3306 | ||
3307 | memcg = parent_mem_cgroup(memcg); | |
3308 | } | |
2e72b634 KS |
3309 | } |
3310 | ||
3311 | static int compare_thresholds(const void *a, const void *b) | |
3312 | { | |
3313 | const struct mem_cgroup_threshold *_a = a; | |
3314 | const struct mem_cgroup_threshold *_b = b; | |
3315 | ||
2bff24a3 GT |
3316 | if (_a->threshold > _b->threshold) |
3317 | return 1; | |
3318 | ||
3319 | if (_a->threshold < _b->threshold) | |
3320 | return -1; | |
3321 | ||
3322 | return 0; | |
2e72b634 KS |
3323 | } |
3324 | ||
c0ff4b85 | 3325 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg) |
9490ff27 KH |
3326 | { |
3327 | struct mem_cgroup_eventfd_list *ev; | |
3328 | ||
2bcf2e92 MH |
3329 | spin_lock(&memcg_oom_lock); |
3330 | ||
c0ff4b85 | 3331 | list_for_each_entry(ev, &memcg->oom_notify, list) |
9490ff27 | 3332 | eventfd_signal(ev->eventfd, 1); |
2bcf2e92 MH |
3333 | |
3334 | spin_unlock(&memcg_oom_lock); | |
9490ff27 KH |
3335 | return 0; |
3336 | } | |
3337 | ||
c0ff4b85 | 3338 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) |
9490ff27 | 3339 | { |
7d74b06f KH |
3340 | struct mem_cgroup *iter; |
3341 | ||
c0ff4b85 | 3342 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 3343 | mem_cgroup_oom_notify_cb(iter); |
9490ff27 KH |
3344 | } |
3345 | ||
59b6f873 | 3346 | static int __mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 | 3347 | struct eventfd_ctx *eventfd, const char *args, enum res_type type) |
2e72b634 | 3348 | { |
2c488db2 KS |
3349 | struct mem_cgroup_thresholds *thresholds; |
3350 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e JW |
3351 | unsigned long threshold; |
3352 | unsigned long usage; | |
2c488db2 | 3353 | int i, size, ret; |
2e72b634 | 3354 | |
650c5e56 | 3355 | ret = page_counter_memparse(args, "-1", &threshold); |
2e72b634 KS |
3356 | if (ret) |
3357 | return ret; | |
3358 | ||
3359 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 3360 | |
05b84301 | 3361 | if (type == _MEM) { |
2c488db2 | 3362 | thresholds = &memcg->thresholds; |
ce00a967 | 3363 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 3364 | } else if (type == _MEMSWAP) { |
2c488db2 | 3365 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 3366 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 3367 | } else |
2e72b634 KS |
3368 | BUG(); |
3369 | ||
2e72b634 | 3370 | /* Check if a threshold crossed before adding a new one */ |
2c488db2 | 3371 | if (thresholds->primary) |
2e72b634 KS |
3372 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
3373 | ||
2c488db2 | 3374 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
3375 | |
3376 | /* Allocate memory for new array of thresholds */ | |
2c488db2 | 3377 | new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold), |
2e72b634 | 3378 | GFP_KERNEL); |
2c488db2 | 3379 | if (!new) { |
2e72b634 KS |
3380 | ret = -ENOMEM; |
3381 | goto unlock; | |
3382 | } | |
2c488db2 | 3383 | new->size = size; |
2e72b634 KS |
3384 | |
3385 | /* Copy thresholds (if any) to new array */ | |
2c488db2 KS |
3386 | if (thresholds->primary) { |
3387 | memcpy(new->entries, thresholds->primary->entries, (size - 1) * | |
2e72b634 | 3388 | sizeof(struct mem_cgroup_threshold)); |
2c488db2 KS |
3389 | } |
3390 | ||
2e72b634 | 3391 | /* Add new threshold */ |
2c488db2 KS |
3392 | new->entries[size - 1].eventfd = eventfd; |
3393 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
3394 | |
3395 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
2c488db2 | 3396 | sort(new->entries, size, sizeof(struct mem_cgroup_threshold), |
2e72b634 KS |
3397 | compare_thresholds, NULL); |
3398 | ||
3399 | /* Find current threshold */ | |
2c488db2 | 3400 | new->current_threshold = -1; |
2e72b634 | 3401 | for (i = 0; i < size; i++) { |
748dad36 | 3402 | if (new->entries[i].threshold <= usage) { |
2e72b634 | 3403 | /* |
2c488db2 KS |
3404 | * new->current_threshold will not be used until |
3405 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
3406 | * it here. |
3407 | */ | |
2c488db2 | 3408 | ++new->current_threshold; |
748dad36 SZ |
3409 | } else |
3410 | break; | |
2e72b634 KS |
3411 | } |
3412 | ||
2c488db2 KS |
3413 | /* Free old spare buffer and save old primary buffer as spare */ |
3414 | kfree(thresholds->spare); | |
3415 | thresholds->spare = thresholds->primary; | |
3416 | ||
3417 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 3418 | |
907860ed | 3419 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
3420 | synchronize_rcu(); |
3421 | ||
2e72b634 KS |
3422 | unlock: |
3423 | mutex_unlock(&memcg->thresholds_lock); | |
3424 | ||
3425 | return ret; | |
3426 | } | |
3427 | ||
59b6f873 | 3428 | static int mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
3429 | struct eventfd_ctx *eventfd, const char *args) |
3430 | { | |
59b6f873 | 3431 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEM); |
347c4a87 TH |
3432 | } |
3433 | ||
59b6f873 | 3434 | static int memsw_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
3435 | struct eventfd_ctx *eventfd, const char *args) |
3436 | { | |
59b6f873 | 3437 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEMSWAP); |
347c4a87 TH |
3438 | } |
3439 | ||
59b6f873 | 3440 | static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 3441 | struct eventfd_ctx *eventfd, enum res_type type) |
2e72b634 | 3442 | { |
2c488db2 KS |
3443 | struct mem_cgroup_thresholds *thresholds; |
3444 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e | 3445 | unsigned long usage; |
2c488db2 | 3446 | int i, j, size; |
2e72b634 KS |
3447 | |
3448 | mutex_lock(&memcg->thresholds_lock); | |
05b84301 JW |
3449 | |
3450 | if (type == _MEM) { | |
2c488db2 | 3451 | thresholds = &memcg->thresholds; |
ce00a967 | 3452 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 3453 | } else if (type == _MEMSWAP) { |
2c488db2 | 3454 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 3455 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 3456 | } else |
2e72b634 KS |
3457 | BUG(); |
3458 | ||
371528ca AV |
3459 | if (!thresholds->primary) |
3460 | goto unlock; | |
3461 | ||
2e72b634 KS |
3462 | /* Check if a threshold crossed before removing */ |
3463 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
3464 | ||
3465 | /* Calculate new number of threshold */ | |
2c488db2 KS |
3466 | size = 0; |
3467 | for (i = 0; i < thresholds->primary->size; i++) { | |
3468 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 KS |
3469 | size++; |
3470 | } | |
3471 | ||
2c488db2 | 3472 | new = thresholds->spare; |
907860ed | 3473 | |
2e72b634 KS |
3474 | /* Set thresholds array to NULL if we don't have thresholds */ |
3475 | if (!size) { | |
2c488db2 KS |
3476 | kfree(new); |
3477 | new = NULL; | |
907860ed | 3478 | goto swap_buffers; |
2e72b634 KS |
3479 | } |
3480 | ||
2c488db2 | 3481 | new->size = size; |
2e72b634 KS |
3482 | |
3483 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
3484 | new->current_threshold = -1; |
3485 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
3486 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
3487 | continue; |
3488 | ||
2c488db2 | 3489 | new->entries[j] = thresholds->primary->entries[i]; |
748dad36 | 3490 | if (new->entries[j].threshold <= usage) { |
2e72b634 | 3491 | /* |
2c488db2 | 3492 | * new->current_threshold will not be used |
2e72b634 KS |
3493 | * until rcu_assign_pointer(), so it's safe to increment |
3494 | * it here. | |
3495 | */ | |
2c488db2 | 3496 | ++new->current_threshold; |
2e72b634 KS |
3497 | } |
3498 | j++; | |
3499 | } | |
3500 | ||
907860ed | 3501 | swap_buffers: |
2c488db2 KS |
3502 | /* Swap primary and spare array */ |
3503 | thresholds->spare = thresholds->primary; | |
8c757763 | 3504 | |
2c488db2 | 3505 | rcu_assign_pointer(thresholds->primary, new); |
2e72b634 | 3506 | |
907860ed | 3507 | /* To be sure that nobody uses thresholds */ |
2e72b634 | 3508 | synchronize_rcu(); |
6611d8d7 MC |
3509 | |
3510 | /* If all events are unregistered, free the spare array */ | |
3511 | if (!new) { | |
3512 | kfree(thresholds->spare); | |
3513 | thresholds->spare = NULL; | |
3514 | } | |
371528ca | 3515 | unlock: |
2e72b634 | 3516 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 3517 | } |
c1e862c1 | 3518 | |
59b6f873 | 3519 | static void mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
3520 | struct eventfd_ctx *eventfd) |
3521 | { | |
59b6f873 | 3522 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEM); |
347c4a87 TH |
3523 | } |
3524 | ||
59b6f873 | 3525 | static void memsw_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
3526 | struct eventfd_ctx *eventfd) |
3527 | { | |
59b6f873 | 3528 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEMSWAP); |
347c4a87 TH |
3529 | } |
3530 | ||
59b6f873 | 3531 | static int mem_cgroup_oom_register_event(struct mem_cgroup *memcg, |
347c4a87 | 3532 | struct eventfd_ctx *eventfd, const char *args) |
9490ff27 | 3533 | { |
9490ff27 | 3534 | struct mem_cgroup_eventfd_list *event; |
9490ff27 | 3535 | |
9490ff27 KH |
3536 | event = kmalloc(sizeof(*event), GFP_KERNEL); |
3537 | if (!event) | |
3538 | return -ENOMEM; | |
3539 | ||
1af8efe9 | 3540 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
3541 | |
3542 | event->eventfd = eventfd; | |
3543 | list_add(&event->list, &memcg->oom_notify); | |
3544 | ||
3545 | /* already in OOM ? */ | |
c2b42d3c | 3546 | if (memcg->under_oom) |
9490ff27 | 3547 | eventfd_signal(eventfd, 1); |
1af8efe9 | 3548 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
3549 | |
3550 | return 0; | |
3551 | } | |
3552 | ||
59b6f873 | 3553 | static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 3554 | struct eventfd_ctx *eventfd) |
9490ff27 | 3555 | { |
9490ff27 | 3556 | struct mem_cgroup_eventfd_list *ev, *tmp; |
9490ff27 | 3557 | |
1af8efe9 | 3558 | spin_lock(&memcg_oom_lock); |
9490ff27 | 3559 | |
c0ff4b85 | 3560 | list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) { |
9490ff27 KH |
3561 | if (ev->eventfd == eventfd) { |
3562 | list_del(&ev->list); | |
3563 | kfree(ev); | |
3564 | } | |
3565 | } | |
3566 | ||
1af8efe9 | 3567 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
3568 | } |
3569 | ||
2da8ca82 | 3570 | static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v) |
3c11ecf4 | 3571 | { |
2da8ca82 | 3572 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(sf)); |
3c11ecf4 | 3573 | |
791badbd | 3574 | seq_printf(sf, "oom_kill_disable %d\n", memcg->oom_kill_disable); |
c2b42d3c | 3575 | seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom); |
8e675f7a | 3576 | seq_printf(sf, "oom_kill %lu\n", memcg_sum_events(memcg, OOM_KILL)); |
3c11ecf4 KH |
3577 | return 0; |
3578 | } | |
3579 | ||
182446d0 | 3580 | static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css, |
3c11ecf4 KH |
3581 | struct cftype *cft, u64 val) |
3582 | { | |
182446d0 | 3583 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3c11ecf4 KH |
3584 | |
3585 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
14208b0e | 3586 | if (!css->parent || !((val == 0) || (val == 1))) |
3c11ecf4 KH |
3587 | return -EINVAL; |
3588 | ||
c0ff4b85 | 3589 | memcg->oom_kill_disable = val; |
4d845ebf | 3590 | if (!val) |
c0ff4b85 | 3591 | memcg_oom_recover(memcg); |
3dae7fec | 3592 | |
3c11ecf4 KH |
3593 | return 0; |
3594 | } | |
3595 | ||
52ebea74 TH |
3596 | #ifdef CONFIG_CGROUP_WRITEBACK |
3597 | ||
3598 | struct list_head *mem_cgroup_cgwb_list(struct mem_cgroup *memcg) | |
3599 | { | |
3600 | return &memcg->cgwb_list; | |
3601 | } | |
3602 | ||
841710aa TH |
3603 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) |
3604 | { | |
3605 | return wb_domain_init(&memcg->cgwb_domain, gfp); | |
3606 | } | |
3607 | ||
3608 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
3609 | { | |
3610 | wb_domain_exit(&memcg->cgwb_domain); | |
3611 | } | |
3612 | ||
2529bb3a TH |
3613 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
3614 | { | |
3615 | wb_domain_size_changed(&memcg->cgwb_domain); | |
3616 | } | |
3617 | ||
841710aa TH |
3618 | struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb) |
3619 | { | |
3620 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
3621 | ||
3622 | if (!memcg->css.parent) | |
3623 | return NULL; | |
3624 | ||
3625 | return &memcg->cgwb_domain; | |
3626 | } | |
3627 | ||
c2aa723a TH |
3628 | /** |
3629 | * mem_cgroup_wb_stats - retrieve writeback related stats from its memcg | |
3630 | * @wb: bdi_writeback in question | |
c5edf9cd TH |
3631 | * @pfilepages: out parameter for number of file pages |
3632 | * @pheadroom: out parameter for number of allocatable pages according to memcg | |
c2aa723a TH |
3633 | * @pdirty: out parameter for number of dirty pages |
3634 | * @pwriteback: out parameter for number of pages under writeback | |
3635 | * | |
c5edf9cd TH |
3636 | * Determine the numbers of file, headroom, dirty, and writeback pages in |
3637 | * @wb's memcg. File, dirty and writeback are self-explanatory. Headroom | |
3638 | * is a bit more involved. | |
c2aa723a | 3639 | * |
c5edf9cd TH |
3640 | * A memcg's headroom is "min(max, high) - used". In the hierarchy, the |
3641 | * headroom is calculated as the lowest headroom of itself and the | |
3642 | * ancestors. Note that this doesn't consider the actual amount of | |
3643 | * available memory in the system. The caller should further cap | |
3644 | * *@pheadroom accordingly. | |
c2aa723a | 3645 | */ |
c5edf9cd TH |
3646 | void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, |
3647 | unsigned long *pheadroom, unsigned long *pdirty, | |
3648 | unsigned long *pwriteback) | |
c2aa723a TH |
3649 | { |
3650 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
3651 | struct mem_cgroup *parent; | |
c2aa723a | 3652 | |
ccda7f43 | 3653 | *pdirty = memcg_page_state(memcg, NR_FILE_DIRTY); |
c2aa723a TH |
3654 | |
3655 | /* this should eventually include NR_UNSTABLE_NFS */ | |
ccda7f43 | 3656 | *pwriteback = memcg_page_state(memcg, NR_WRITEBACK); |
c5edf9cd TH |
3657 | *pfilepages = mem_cgroup_nr_lru_pages(memcg, (1 << LRU_INACTIVE_FILE) | |
3658 | (1 << LRU_ACTIVE_FILE)); | |
3659 | *pheadroom = PAGE_COUNTER_MAX; | |
c2aa723a | 3660 | |
c2aa723a TH |
3661 | while ((parent = parent_mem_cgroup(memcg))) { |
3662 | unsigned long ceiling = min(memcg->memory.limit, memcg->high); | |
3663 | unsigned long used = page_counter_read(&memcg->memory); | |
3664 | ||
c5edf9cd | 3665 | *pheadroom = min(*pheadroom, ceiling - min(ceiling, used)); |
c2aa723a TH |
3666 | memcg = parent; |
3667 | } | |
c2aa723a TH |
3668 | } |
3669 | ||
841710aa TH |
3670 | #else /* CONFIG_CGROUP_WRITEBACK */ |
3671 | ||
3672 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) | |
3673 | { | |
3674 | return 0; | |
3675 | } | |
3676 | ||
3677 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
3678 | { | |
3679 | } | |
3680 | ||
2529bb3a TH |
3681 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
3682 | { | |
3683 | } | |
3684 | ||
52ebea74 TH |
3685 | #endif /* CONFIG_CGROUP_WRITEBACK */ |
3686 | ||
3bc942f3 TH |
3687 | /* |
3688 | * DO NOT USE IN NEW FILES. | |
3689 | * | |
3690 | * "cgroup.event_control" implementation. | |
3691 | * | |
3692 | * This is way over-engineered. It tries to support fully configurable | |
3693 | * events for each user. Such level of flexibility is completely | |
3694 | * unnecessary especially in the light of the planned unified hierarchy. | |
3695 | * | |
3696 | * Please deprecate this and replace with something simpler if at all | |
3697 | * possible. | |
3698 | */ | |
3699 | ||
79bd9814 TH |
3700 | /* |
3701 | * Unregister event and free resources. | |
3702 | * | |
3703 | * Gets called from workqueue. | |
3704 | */ | |
3bc942f3 | 3705 | static void memcg_event_remove(struct work_struct *work) |
79bd9814 | 3706 | { |
3bc942f3 TH |
3707 | struct mem_cgroup_event *event = |
3708 | container_of(work, struct mem_cgroup_event, remove); | |
59b6f873 | 3709 | struct mem_cgroup *memcg = event->memcg; |
79bd9814 TH |
3710 | |
3711 | remove_wait_queue(event->wqh, &event->wait); | |
3712 | ||
59b6f873 | 3713 | event->unregister_event(memcg, event->eventfd); |
79bd9814 TH |
3714 | |
3715 | /* Notify userspace the event is going away. */ | |
3716 | eventfd_signal(event->eventfd, 1); | |
3717 | ||
3718 | eventfd_ctx_put(event->eventfd); | |
3719 | kfree(event); | |
59b6f873 | 3720 | css_put(&memcg->css); |
79bd9814 TH |
3721 | } |
3722 | ||
3723 | /* | |
3724 | * Gets called on POLLHUP on eventfd when user closes it. | |
3725 | * | |
3726 | * Called with wqh->lock held and interrupts disabled. | |
3727 | */ | |
ac6424b9 | 3728 | static int memcg_event_wake(wait_queue_entry_t *wait, unsigned mode, |
3bc942f3 | 3729 | int sync, void *key) |
79bd9814 | 3730 | { |
3bc942f3 TH |
3731 | struct mem_cgroup_event *event = |
3732 | container_of(wait, struct mem_cgroup_event, wait); | |
59b6f873 | 3733 | struct mem_cgroup *memcg = event->memcg; |
79bd9814 TH |
3734 | unsigned long flags = (unsigned long)key; |
3735 | ||
3736 | if (flags & POLLHUP) { | |
3737 | /* | |
3738 | * If the event has been detached at cgroup removal, we | |
3739 | * can simply return knowing the other side will cleanup | |
3740 | * for us. | |
3741 | * | |
3742 | * We can't race against event freeing since the other | |
3743 | * side will require wqh->lock via remove_wait_queue(), | |
3744 | * which we hold. | |
3745 | */ | |
fba94807 | 3746 | spin_lock(&memcg->event_list_lock); |
79bd9814 TH |
3747 | if (!list_empty(&event->list)) { |
3748 | list_del_init(&event->list); | |
3749 | /* | |
3750 | * We are in atomic context, but cgroup_event_remove() | |
3751 | * may sleep, so we have to call it in workqueue. | |
3752 | */ | |
3753 | schedule_work(&event->remove); | |
3754 | } | |
fba94807 | 3755 | spin_unlock(&memcg->event_list_lock); |
79bd9814 TH |
3756 | } |
3757 | ||
3758 | return 0; | |
3759 | } | |
3760 | ||
3bc942f3 | 3761 | static void memcg_event_ptable_queue_proc(struct file *file, |
79bd9814 TH |
3762 | wait_queue_head_t *wqh, poll_table *pt) |
3763 | { | |
3bc942f3 TH |
3764 | struct mem_cgroup_event *event = |
3765 | container_of(pt, struct mem_cgroup_event, pt); | |
79bd9814 TH |
3766 | |
3767 | event->wqh = wqh; | |
3768 | add_wait_queue(wqh, &event->wait); | |
3769 | } | |
3770 | ||
3771 | /* | |
3bc942f3 TH |
3772 | * DO NOT USE IN NEW FILES. |
3773 | * | |
79bd9814 TH |
3774 | * Parse input and register new cgroup event handler. |
3775 | * | |
3776 | * Input must be in format '<event_fd> <control_fd> <args>'. | |
3777 | * Interpretation of args is defined by control file implementation. | |
3778 | */ | |
451af504 TH |
3779 | static ssize_t memcg_write_event_control(struct kernfs_open_file *of, |
3780 | char *buf, size_t nbytes, loff_t off) | |
79bd9814 | 3781 | { |
451af504 | 3782 | struct cgroup_subsys_state *css = of_css(of); |
fba94807 | 3783 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 3784 | struct mem_cgroup_event *event; |
79bd9814 TH |
3785 | struct cgroup_subsys_state *cfile_css; |
3786 | unsigned int efd, cfd; | |
3787 | struct fd efile; | |
3788 | struct fd cfile; | |
fba94807 | 3789 | const char *name; |
79bd9814 TH |
3790 | char *endp; |
3791 | int ret; | |
3792 | ||
451af504 TH |
3793 | buf = strstrip(buf); |
3794 | ||
3795 | efd = simple_strtoul(buf, &endp, 10); | |
79bd9814 TH |
3796 | if (*endp != ' ') |
3797 | return -EINVAL; | |
451af504 | 3798 | buf = endp + 1; |
79bd9814 | 3799 | |
451af504 | 3800 | cfd = simple_strtoul(buf, &endp, 10); |
79bd9814 TH |
3801 | if ((*endp != ' ') && (*endp != '\0')) |
3802 | return -EINVAL; | |
451af504 | 3803 | buf = endp + 1; |
79bd9814 TH |
3804 | |
3805 | event = kzalloc(sizeof(*event), GFP_KERNEL); | |
3806 | if (!event) | |
3807 | return -ENOMEM; | |
3808 | ||
59b6f873 | 3809 | event->memcg = memcg; |
79bd9814 | 3810 | INIT_LIST_HEAD(&event->list); |
3bc942f3 TH |
3811 | init_poll_funcptr(&event->pt, memcg_event_ptable_queue_proc); |
3812 | init_waitqueue_func_entry(&event->wait, memcg_event_wake); | |
3813 | INIT_WORK(&event->remove, memcg_event_remove); | |
79bd9814 TH |
3814 | |
3815 | efile = fdget(efd); | |
3816 | if (!efile.file) { | |
3817 | ret = -EBADF; | |
3818 | goto out_kfree; | |
3819 | } | |
3820 | ||
3821 | event->eventfd = eventfd_ctx_fileget(efile.file); | |
3822 | if (IS_ERR(event->eventfd)) { | |
3823 | ret = PTR_ERR(event->eventfd); | |
3824 | goto out_put_efile; | |
3825 | } | |
3826 | ||
3827 | cfile = fdget(cfd); | |
3828 | if (!cfile.file) { | |
3829 | ret = -EBADF; | |
3830 | goto out_put_eventfd; | |
3831 | } | |
3832 | ||
3833 | /* the process need read permission on control file */ | |
3834 | /* AV: shouldn't we check that it's been opened for read instead? */ | |
3835 | ret = inode_permission(file_inode(cfile.file), MAY_READ); | |
3836 | if (ret < 0) | |
3837 | goto out_put_cfile; | |
3838 | ||
fba94807 TH |
3839 | /* |
3840 | * Determine the event callbacks and set them in @event. This used | |
3841 | * to be done via struct cftype but cgroup core no longer knows | |
3842 | * about these events. The following is crude but the whole thing | |
3843 | * is for compatibility anyway. | |
3bc942f3 TH |
3844 | * |
3845 | * DO NOT ADD NEW FILES. | |
fba94807 | 3846 | */ |
b583043e | 3847 | name = cfile.file->f_path.dentry->d_name.name; |
fba94807 TH |
3848 | |
3849 | if (!strcmp(name, "memory.usage_in_bytes")) { | |
3850 | event->register_event = mem_cgroup_usage_register_event; | |
3851 | event->unregister_event = mem_cgroup_usage_unregister_event; | |
3852 | } else if (!strcmp(name, "memory.oom_control")) { | |
3853 | event->register_event = mem_cgroup_oom_register_event; | |
3854 | event->unregister_event = mem_cgroup_oom_unregister_event; | |
3855 | } else if (!strcmp(name, "memory.pressure_level")) { | |
3856 | event->register_event = vmpressure_register_event; | |
3857 | event->unregister_event = vmpressure_unregister_event; | |
3858 | } else if (!strcmp(name, "memory.memsw.usage_in_bytes")) { | |
347c4a87 TH |
3859 | event->register_event = memsw_cgroup_usage_register_event; |
3860 | event->unregister_event = memsw_cgroup_usage_unregister_event; | |
fba94807 TH |
3861 | } else { |
3862 | ret = -EINVAL; | |
3863 | goto out_put_cfile; | |
3864 | } | |
3865 | ||
79bd9814 | 3866 | /* |
b5557c4c TH |
3867 | * Verify @cfile should belong to @css. Also, remaining events are |
3868 | * automatically removed on cgroup destruction but the removal is | |
3869 | * asynchronous, so take an extra ref on @css. | |
79bd9814 | 3870 | */ |
b583043e | 3871 | cfile_css = css_tryget_online_from_dir(cfile.file->f_path.dentry->d_parent, |
ec903c0c | 3872 | &memory_cgrp_subsys); |
79bd9814 | 3873 | ret = -EINVAL; |
5a17f543 | 3874 | if (IS_ERR(cfile_css)) |
79bd9814 | 3875 | goto out_put_cfile; |
5a17f543 TH |
3876 | if (cfile_css != css) { |
3877 | css_put(cfile_css); | |
79bd9814 | 3878 | goto out_put_cfile; |
5a17f543 | 3879 | } |
79bd9814 | 3880 | |
451af504 | 3881 | ret = event->register_event(memcg, event->eventfd, buf); |
79bd9814 TH |
3882 | if (ret) |
3883 | goto out_put_css; | |
3884 | ||
3885 | efile.file->f_op->poll(efile.file, &event->pt); | |
3886 | ||
fba94807 TH |
3887 | spin_lock(&memcg->event_list_lock); |
3888 | list_add(&event->list, &memcg->event_list); | |
3889 | spin_unlock(&memcg->event_list_lock); | |
79bd9814 TH |
3890 | |
3891 | fdput(cfile); | |
3892 | fdput(efile); | |
3893 | ||
451af504 | 3894 | return nbytes; |
79bd9814 TH |
3895 | |
3896 | out_put_css: | |
b5557c4c | 3897 | css_put(css); |
79bd9814 TH |
3898 | out_put_cfile: |
3899 | fdput(cfile); | |
3900 | out_put_eventfd: | |
3901 | eventfd_ctx_put(event->eventfd); | |
3902 | out_put_efile: | |
3903 | fdput(efile); | |
3904 | out_kfree: | |
3905 | kfree(event); | |
3906 | ||
3907 | return ret; | |
3908 | } | |
3909 | ||
241994ed | 3910 | static struct cftype mem_cgroup_legacy_files[] = { |
8cdea7c0 | 3911 | { |
0eea1030 | 3912 | .name = "usage_in_bytes", |
8c7c6e34 | 3913 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
791badbd | 3914 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 3915 | }, |
c84872e1 PE |
3916 | { |
3917 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 3918 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
6770c64e | 3919 | .write = mem_cgroup_reset, |
791badbd | 3920 | .read_u64 = mem_cgroup_read_u64, |
c84872e1 | 3921 | }, |
8cdea7c0 | 3922 | { |
0eea1030 | 3923 | .name = "limit_in_bytes", |
8c7c6e34 | 3924 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
451af504 | 3925 | .write = mem_cgroup_write, |
791badbd | 3926 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 3927 | }, |
296c81d8 BS |
3928 | { |
3929 | .name = "soft_limit_in_bytes", | |
3930 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
451af504 | 3931 | .write = mem_cgroup_write, |
791badbd | 3932 | .read_u64 = mem_cgroup_read_u64, |
296c81d8 | 3933 | }, |
8cdea7c0 BS |
3934 | { |
3935 | .name = "failcnt", | |
8c7c6e34 | 3936 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
6770c64e | 3937 | .write = mem_cgroup_reset, |
791badbd | 3938 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 3939 | }, |
d2ceb9b7 KH |
3940 | { |
3941 | .name = "stat", | |
2da8ca82 | 3942 | .seq_show = memcg_stat_show, |
d2ceb9b7 | 3943 | }, |
c1e862c1 KH |
3944 | { |
3945 | .name = "force_empty", | |
6770c64e | 3946 | .write = mem_cgroup_force_empty_write, |
c1e862c1 | 3947 | }, |
18f59ea7 BS |
3948 | { |
3949 | .name = "use_hierarchy", | |
3950 | .write_u64 = mem_cgroup_hierarchy_write, | |
3951 | .read_u64 = mem_cgroup_hierarchy_read, | |
3952 | }, | |
79bd9814 | 3953 | { |
3bc942f3 | 3954 | .name = "cgroup.event_control", /* XXX: for compat */ |
451af504 | 3955 | .write = memcg_write_event_control, |
7dbdb199 | 3956 | .flags = CFTYPE_NO_PREFIX | CFTYPE_WORLD_WRITABLE, |
79bd9814 | 3957 | }, |
a7885eb8 KM |
3958 | { |
3959 | .name = "swappiness", | |
3960 | .read_u64 = mem_cgroup_swappiness_read, | |
3961 | .write_u64 = mem_cgroup_swappiness_write, | |
3962 | }, | |
7dc74be0 DN |
3963 | { |
3964 | .name = "move_charge_at_immigrate", | |
3965 | .read_u64 = mem_cgroup_move_charge_read, | |
3966 | .write_u64 = mem_cgroup_move_charge_write, | |
3967 | }, | |
9490ff27 KH |
3968 | { |
3969 | .name = "oom_control", | |
2da8ca82 | 3970 | .seq_show = mem_cgroup_oom_control_read, |
3c11ecf4 | 3971 | .write_u64 = mem_cgroup_oom_control_write, |
9490ff27 KH |
3972 | .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), |
3973 | }, | |
70ddf637 AV |
3974 | { |
3975 | .name = "pressure_level", | |
70ddf637 | 3976 | }, |
406eb0c9 YH |
3977 | #ifdef CONFIG_NUMA |
3978 | { | |
3979 | .name = "numa_stat", | |
2da8ca82 | 3980 | .seq_show = memcg_numa_stat_show, |
406eb0c9 YH |
3981 | }, |
3982 | #endif | |
510fc4e1 GC |
3983 | { |
3984 | .name = "kmem.limit_in_bytes", | |
3985 | .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT), | |
451af504 | 3986 | .write = mem_cgroup_write, |
791badbd | 3987 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
3988 | }, |
3989 | { | |
3990 | .name = "kmem.usage_in_bytes", | |
3991 | .private = MEMFILE_PRIVATE(_KMEM, RES_USAGE), | |
791badbd | 3992 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
3993 | }, |
3994 | { | |
3995 | .name = "kmem.failcnt", | |
3996 | .private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT), | |
6770c64e | 3997 | .write = mem_cgroup_reset, |
791badbd | 3998 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
3999 | }, |
4000 | { | |
4001 | .name = "kmem.max_usage_in_bytes", | |
4002 | .private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE), | |
6770c64e | 4003 | .write = mem_cgroup_reset, |
791badbd | 4004 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 | 4005 | }, |
749c5415 GC |
4006 | #ifdef CONFIG_SLABINFO |
4007 | { | |
4008 | .name = "kmem.slabinfo", | |
bc2791f8 TH |
4009 | .seq_start = memcg_slab_start, |
4010 | .seq_next = memcg_slab_next, | |
4011 | .seq_stop = memcg_slab_stop, | |
b047501c | 4012 | .seq_show = memcg_slab_show, |
749c5415 GC |
4013 | }, |
4014 | #endif | |
d55f90bf VD |
4015 | { |
4016 | .name = "kmem.tcp.limit_in_bytes", | |
4017 | .private = MEMFILE_PRIVATE(_TCP, RES_LIMIT), | |
4018 | .write = mem_cgroup_write, | |
4019 | .read_u64 = mem_cgroup_read_u64, | |
4020 | }, | |
4021 | { | |
4022 | .name = "kmem.tcp.usage_in_bytes", | |
4023 | .private = MEMFILE_PRIVATE(_TCP, RES_USAGE), | |
4024 | .read_u64 = mem_cgroup_read_u64, | |
4025 | }, | |
4026 | { | |
4027 | .name = "kmem.tcp.failcnt", | |
4028 | .private = MEMFILE_PRIVATE(_TCP, RES_FAILCNT), | |
4029 | .write = mem_cgroup_reset, | |
4030 | .read_u64 = mem_cgroup_read_u64, | |
4031 | }, | |
4032 | { | |
4033 | .name = "kmem.tcp.max_usage_in_bytes", | |
4034 | .private = MEMFILE_PRIVATE(_TCP, RES_MAX_USAGE), | |
4035 | .write = mem_cgroup_reset, | |
4036 | .read_u64 = mem_cgroup_read_u64, | |
4037 | }, | |
6bc10349 | 4038 | { }, /* terminate */ |
af36f906 | 4039 | }; |
8c7c6e34 | 4040 | |
73f576c0 JW |
4041 | /* |
4042 | * Private memory cgroup IDR | |
4043 | * | |
4044 | * Swap-out records and page cache shadow entries need to store memcg | |
4045 | * references in constrained space, so we maintain an ID space that is | |
4046 | * limited to 16 bit (MEM_CGROUP_ID_MAX), limiting the total number of | |
4047 | * memory-controlled cgroups to 64k. | |
4048 | * | |
4049 | * However, there usually are many references to the oflline CSS after | |
4050 | * the cgroup has been destroyed, such as page cache or reclaimable | |
4051 | * slab objects, that don't need to hang on to the ID. We want to keep | |
4052 | * those dead CSS from occupying IDs, or we might quickly exhaust the | |
4053 | * relatively small ID space and prevent the creation of new cgroups | |
4054 | * even when there are much fewer than 64k cgroups - possibly none. | |
4055 | * | |
4056 | * Maintain a private 16-bit ID space for memcg, and allow the ID to | |
4057 | * be freed and recycled when it's no longer needed, which is usually | |
4058 | * when the CSS is offlined. | |
4059 | * | |
4060 | * The only exception to that are records of swapped out tmpfs/shmem | |
4061 | * pages that need to be attributed to live ancestors on swapin. But | |
4062 | * those references are manageable from userspace. | |
4063 | */ | |
4064 | ||
4065 | static DEFINE_IDR(mem_cgroup_idr); | |
4066 | ||
615d66c3 | 4067 | static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned int n) |
73f576c0 | 4068 | { |
58fa2a55 | 4069 | VM_BUG_ON(atomic_read(&memcg->id.ref) <= 0); |
615d66c3 | 4070 | atomic_add(n, &memcg->id.ref); |
73f576c0 JW |
4071 | } |
4072 | ||
615d66c3 | 4073 | static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n) |
73f576c0 | 4074 | { |
58fa2a55 | 4075 | VM_BUG_ON(atomic_read(&memcg->id.ref) < n); |
615d66c3 | 4076 | if (atomic_sub_and_test(n, &memcg->id.ref)) { |
73f576c0 JW |
4077 | idr_remove(&mem_cgroup_idr, memcg->id.id); |
4078 | memcg->id.id = 0; | |
4079 | ||
4080 | /* Memcg ID pins CSS */ | |
4081 | css_put(&memcg->css); | |
4082 | } | |
4083 | } | |
4084 | ||
615d66c3 VD |
4085 | static inline void mem_cgroup_id_get(struct mem_cgroup *memcg) |
4086 | { | |
4087 | mem_cgroup_id_get_many(memcg, 1); | |
4088 | } | |
4089 | ||
4090 | static inline void mem_cgroup_id_put(struct mem_cgroup *memcg) | |
4091 | { | |
4092 | mem_cgroup_id_put_many(memcg, 1); | |
4093 | } | |
4094 | ||
73f576c0 JW |
4095 | /** |
4096 | * mem_cgroup_from_id - look up a memcg from a memcg id | |
4097 | * @id: the memcg id to look up | |
4098 | * | |
4099 | * Caller must hold rcu_read_lock(). | |
4100 | */ | |
4101 | struct mem_cgroup *mem_cgroup_from_id(unsigned short id) | |
4102 | { | |
4103 | WARN_ON_ONCE(!rcu_read_lock_held()); | |
4104 | return idr_find(&mem_cgroup_idr, id); | |
4105 | } | |
4106 | ||
ef8f2327 | 4107 | static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) |
6d12e2d8 KH |
4108 | { |
4109 | struct mem_cgroup_per_node *pn; | |
ef8f2327 | 4110 | int tmp = node; |
1ecaab2b KH |
4111 | /* |
4112 | * This routine is called against possible nodes. | |
4113 | * But it's BUG to call kmalloc() against offline node. | |
4114 | * | |
4115 | * TODO: this routine can waste much memory for nodes which will | |
4116 | * never be onlined. It's better to use memory hotplug callback | |
4117 | * function. | |
4118 | */ | |
41e3355d KH |
4119 | if (!node_state(node, N_NORMAL_MEMORY)) |
4120 | tmp = -1; | |
17295c88 | 4121 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); |
6d12e2d8 KH |
4122 | if (!pn) |
4123 | return 1; | |
1ecaab2b | 4124 | |
00f3ca2c JW |
4125 | pn->lruvec_stat = alloc_percpu(struct lruvec_stat); |
4126 | if (!pn->lruvec_stat) { | |
4127 | kfree(pn); | |
4128 | return 1; | |
4129 | } | |
4130 | ||
ef8f2327 MG |
4131 | lruvec_init(&pn->lruvec); |
4132 | pn->usage_in_excess = 0; | |
4133 | pn->on_tree = false; | |
4134 | pn->memcg = memcg; | |
4135 | ||
54f72fe0 | 4136 | memcg->nodeinfo[node] = pn; |
6d12e2d8 KH |
4137 | return 0; |
4138 | } | |
4139 | ||
ef8f2327 | 4140 | static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) |
1ecaab2b | 4141 | { |
00f3ca2c JW |
4142 | struct mem_cgroup_per_node *pn = memcg->nodeinfo[node]; |
4143 | ||
4144 | free_percpu(pn->lruvec_stat); | |
4145 | kfree(pn); | |
1ecaab2b KH |
4146 | } |
4147 | ||
40e952f9 | 4148 | static void __mem_cgroup_free(struct mem_cgroup *memcg) |
59927fb9 | 4149 | { |
c8b2a36f | 4150 | int node; |
59927fb9 | 4151 | |
c8b2a36f | 4152 | for_each_node(node) |
ef8f2327 | 4153 | free_mem_cgroup_per_node_info(memcg, node); |
c8b2a36f | 4154 | free_percpu(memcg->stat); |
8ff69e2c | 4155 | kfree(memcg); |
59927fb9 | 4156 | } |
3afe36b1 | 4157 | |
40e952f9 TE |
4158 | static void mem_cgroup_free(struct mem_cgroup *memcg) |
4159 | { | |
4160 | memcg_wb_domain_exit(memcg); | |
4161 | __mem_cgroup_free(memcg); | |
4162 | } | |
4163 | ||
0b8f73e1 | 4164 | static struct mem_cgroup *mem_cgroup_alloc(void) |
8cdea7c0 | 4165 | { |
d142e3e6 | 4166 | struct mem_cgroup *memcg; |
0b8f73e1 | 4167 | size_t size; |
6d12e2d8 | 4168 | int node; |
8cdea7c0 | 4169 | |
0b8f73e1 JW |
4170 | size = sizeof(struct mem_cgroup); |
4171 | size += nr_node_ids * sizeof(struct mem_cgroup_per_node *); | |
4172 | ||
4173 | memcg = kzalloc(size, GFP_KERNEL); | |
c0ff4b85 | 4174 | if (!memcg) |
0b8f73e1 JW |
4175 | return NULL; |
4176 | ||
73f576c0 JW |
4177 | memcg->id.id = idr_alloc(&mem_cgroup_idr, NULL, |
4178 | 1, MEM_CGROUP_ID_MAX, | |
4179 | GFP_KERNEL); | |
4180 | if (memcg->id.id < 0) | |
4181 | goto fail; | |
4182 | ||
0b8f73e1 JW |
4183 | memcg->stat = alloc_percpu(struct mem_cgroup_stat_cpu); |
4184 | if (!memcg->stat) | |
4185 | goto fail; | |
78fb7466 | 4186 | |
3ed28fa1 | 4187 | for_each_node(node) |
ef8f2327 | 4188 | if (alloc_mem_cgroup_per_node_info(memcg, node)) |
0b8f73e1 | 4189 | goto fail; |
f64c3f54 | 4190 | |
0b8f73e1 JW |
4191 | if (memcg_wb_domain_init(memcg, GFP_KERNEL)) |
4192 | goto fail; | |
28dbc4b6 | 4193 | |
f7e1cb6e | 4194 | INIT_WORK(&memcg->high_work, high_work_func); |
d142e3e6 GC |
4195 | memcg->last_scanned_node = MAX_NUMNODES; |
4196 | INIT_LIST_HEAD(&memcg->oom_notify); | |
d142e3e6 GC |
4197 | mutex_init(&memcg->thresholds_lock); |
4198 | spin_lock_init(&memcg->move_lock); | |
70ddf637 | 4199 | vmpressure_init(&memcg->vmpressure); |
fba94807 TH |
4200 | INIT_LIST_HEAD(&memcg->event_list); |
4201 | spin_lock_init(&memcg->event_list_lock); | |
d886f4e4 | 4202 | memcg->socket_pressure = jiffies; |
127424c8 | 4203 | #ifndef CONFIG_SLOB |
900a38f0 | 4204 | memcg->kmemcg_id = -1; |
900a38f0 | 4205 | #endif |
52ebea74 TH |
4206 | #ifdef CONFIG_CGROUP_WRITEBACK |
4207 | INIT_LIST_HEAD(&memcg->cgwb_list); | |
4208 | #endif | |
73f576c0 | 4209 | idr_replace(&mem_cgroup_idr, memcg, memcg->id.id); |
0b8f73e1 JW |
4210 | return memcg; |
4211 | fail: | |
73f576c0 JW |
4212 | if (memcg->id.id > 0) |
4213 | idr_remove(&mem_cgroup_idr, memcg->id.id); | |
40e952f9 | 4214 | __mem_cgroup_free(memcg); |
0b8f73e1 | 4215 | return NULL; |
d142e3e6 GC |
4216 | } |
4217 | ||
0b8f73e1 JW |
4218 | static struct cgroup_subsys_state * __ref |
4219 | mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
d142e3e6 | 4220 | { |
0b8f73e1 JW |
4221 | struct mem_cgroup *parent = mem_cgroup_from_css(parent_css); |
4222 | struct mem_cgroup *memcg; | |
4223 | long error = -ENOMEM; | |
d142e3e6 | 4224 | |
0b8f73e1 JW |
4225 | memcg = mem_cgroup_alloc(); |
4226 | if (!memcg) | |
4227 | return ERR_PTR(error); | |
d142e3e6 | 4228 | |
0b8f73e1 JW |
4229 | memcg->high = PAGE_COUNTER_MAX; |
4230 | memcg->soft_limit = PAGE_COUNTER_MAX; | |
4231 | if (parent) { | |
4232 | memcg->swappiness = mem_cgroup_swappiness(parent); | |
4233 | memcg->oom_kill_disable = parent->oom_kill_disable; | |
4234 | } | |
4235 | if (parent && parent->use_hierarchy) { | |
4236 | memcg->use_hierarchy = true; | |
3e32cb2e | 4237 | page_counter_init(&memcg->memory, &parent->memory); |
37e84351 | 4238 | page_counter_init(&memcg->swap, &parent->swap); |
3e32cb2e JW |
4239 | page_counter_init(&memcg->memsw, &parent->memsw); |
4240 | page_counter_init(&memcg->kmem, &parent->kmem); | |
0db15298 | 4241 | page_counter_init(&memcg->tcpmem, &parent->tcpmem); |
18f59ea7 | 4242 | } else { |
3e32cb2e | 4243 | page_counter_init(&memcg->memory, NULL); |
37e84351 | 4244 | page_counter_init(&memcg->swap, NULL); |
3e32cb2e JW |
4245 | page_counter_init(&memcg->memsw, NULL); |
4246 | page_counter_init(&memcg->kmem, NULL); | |
0db15298 | 4247 | page_counter_init(&memcg->tcpmem, NULL); |
8c7f6edb TH |
4248 | /* |
4249 | * Deeper hierachy with use_hierarchy == false doesn't make | |
4250 | * much sense so let cgroup subsystem know about this | |
4251 | * unfortunate state in our controller. | |
4252 | */ | |
d142e3e6 | 4253 | if (parent != root_mem_cgroup) |
073219e9 | 4254 | memory_cgrp_subsys.broken_hierarchy = true; |
18f59ea7 | 4255 | } |
d6441637 | 4256 | |
0b8f73e1 JW |
4257 | /* The following stuff does not apply to the root */ |
4258 | if (!parent) { | |
4259 | root_mem_cgroup = memcg; | |
4260 | return &memcg->css; | |
4261 | } | |
4262 | ||
b313aeee | 4263 | error = memcg_online_kmem(memcg); |
0b8f73e1 JW |
4264 | if (error) |
4265 | goto fail; | |
127424c8 | 4266 | |
f7e1cb6e | 4267 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 4268 | static_branch_inc(&memcg_sockets_enabled_key); |
f7e1cb6e | 4269 | |
0b8f73e1 JW |
4270 | return &memcg->css; |
4271 | fail: | |
4272 | mem_cgroup_free(memcg); | |
ea3a9645 | 4273 | return ERR_PTR(-ENOMEM); |
0b8f73e1 JW |
4274 | } |
4275 | ||
73f576c0 | 4276 | static int mem_cgroup_css_online(struct cgroup_subsys_state *css) |
0b8f73e1 | 4277 | { |
58fa2a55 VD |
4278 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
4279 | ||
73f576c0 | 4280 | /* Online state pins memcg ID, memcg ID pins CSS */ |
58fa2a55 | 4281 | atomic_set(&memcg->id.ref, 1); |
73f576c0 | 4282 | css_get(css); |
2f7dd7a4 | 4283 | return 0; |
8cdea7c0 BS |
4284 | } |
4285 | ||
eb95419b | 4286 | static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) |
df878fb0 | 4287 | { |
eb95419b | 4288 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 4289 | struct mem_cgroup_event *event, *tmp; |
79bd9814 TH |
4290 | |
4291 | /* | |
4292 | * Unregister events and notify userspace. | |
4293 | * Notify userspace about cgroup removing only after rmdir of cgroup | |
4294 | * directory to avoid race between userspace and kernelspace. | |
4295 | */ | |
fba94807 TH |
4296 | spin_lock(&memcg->event_list_lock); |
4297 | list_for_each_entry_safe(event, tmp, &memcg->event_list, list) { | |
79bd9814 TH |
4298 | list_del_init(&event->list); |
4299 | schedule_work(&event->remove); | |
4300 | } | |
fba94807 | 4301 | spin_unlock(&memcg->event_list_lock); |
ec64f515 | 4302 | |
567e9ab2 | 4303 | memcg_offline_kmem(memcg); |
52ebea74 | 4304 | wb_memcg_offline(memcg); |
73f576c0 JW |
4305 | |
4306 | mem_cgroup_id_put(memcg); | |
df878fb0 KH |
4307 | } |
4308 | ||
6df38689 VD |
4309 | static void mem_cgroup_css_released(struct cgroup_subsys_state *css) |
4310 | { | |
4311 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
4312 | ||
4313 | invalidate_reclaim_iterators(memcg); | |
4314 | } | |
4315 | ||
eb95419b | 4316 | static void mem_cgroup_css_free(struct cgroup_subsys_state *css) |
8cdea7c0 | 4317 | { |
eb95419b | 4318 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
c268e994 | 4319 | |
f7e1cb6e | 4320 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 4321 | static_branch_dec(&memcg_sockets_enabled_key); |
127424c8 | 4322 | |
0db15298 | 4323 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_active) |
d55f90bf | 4324 | static_branch_dec(&memcg_sockets_enabled_key); |
3893e302 | 4325 | |
0b8f73e1 JW |
4326 | vmpressure_cleanup(&memcg->vmpressure); |
4327 | cancel_work_sync(&memcg->high_work); | |
4328 | mem_cgroup_remove_from_trees(memcg); | |
d886f4e4 | 4329 | memcg_free_kmem(memcg); |
0b8f73e1 | 4330 | mem_cgroup_free(memcg); |
8cdea7c0 BS |
4331 | } |
4332 | ||
1ced953b TH |
4333 | /** |
4334 | * mem_cgroup_css_reset - reset the states of a mem_cgroup | |
4335 | * @css: the target css | |
4336 | * | |
4337 | * Reset the states of the mem_cgroup associated with @css. This is | |
4338 | * invoked when the userland requests disabling on the default hierarchy | |
4339 | * but the memcg is pinned through dependency. The memcg should stop | |
4340 | * applying policies and should revert to the vanilla state as it may be | |
4341 | * made visible again. | |
4342 | * | |
4343 | * The current implementation only resets the essential configurations. | |
4344 | * This needs to be expanded to cover all the visible parts. | |
4345 | */ | |
4346 | static void mem_cgroup_css_reset(struct cgroup_subsys_state *css) | |
4347 | { | |
4348 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
4349 | ||
d334c9bc VD |
4350 | page_counter_limit(&memcg->memory, PAGE_COUNTER_MAX); |
4351 | page_counter_limit(&memcg->swap, PAGE_COUNTER_MAX); | |
4352 | page_counter_limit(&memcg->memsw, PAGE_COUNTER_MAX); | |
4353 | page_counter_limit(&memcg->kmem, PAGE_COUNTER_MAX); | |
4354 | page_counter_limit(&memcg->tcpmem, PAGE_COUNTER_MAX); | |
241994ed JW |
4355 | memcg->low = 0; |
4356 | memcg->high = PAGE_COUNTER_MAX; | |
24d404dc | 4357 | memcg->soft_limit = PAGE_COUNTER_MAX; |
2529bb3a | 4358 | memcg_wb_domain_size_changed(memcg); |
1ced953b TH |
4359 | } |
4360 | ||
02491447 | 4361 | #ifdef CONFIG_MMU |
7dc74be0 | 4362 | /* Handlers for move charge at task migration. */ |
854ffa8d | 4363 | static int mem_cgroup_do_precharge(unsigned long count) |
7dc74be0 | 4364 | { |
05b84301 | 4365 | int ret; |
9476db97 | 4366 | |
d0164adc MG |
4367 | /* Try a single bulk charge without reclaim first, kswapd may wake */ |
4368 | ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_DIRECT_RECLAIM, count); | |
9476db97 | 4369 | if (!ret) { |
854ffa8d | 4370 | mc.precharge += count; |
854ffa8d DN |
4371 | return ret; |
4372 | } | |
9476db97 | 4373 | |
3674534b | 4374 | /* Try charges one by one with reclaim, but do not retry */ |
854ffa8d | 4375 | while (count--) { |
3674534b | 4376 | ret = try_charge(mc.to, GFP_KERNEL | __GFP_NORETRY, 1); |
38c5d72f | 4377 | if (ret) |
38c5d72f | 4378 | return ret; |
854ffa8d | 4379 | mc.precharge++; |
9476db97 | 4380 | cond_resched(); |
854ffa8d | 4381 | } |
9476db97 | 4382 | return 0; |
4ffef5fe DN |
4383 | } |
4384 | ||
4ffef5fe DN |
4385 | union mc_target { |
4386 | struct page *page; | |
02491447 | 4387 | swp_entry_t ent; |
4ffef5fe DN |
4388 | }; |
4389 | ||
4ffef5fe | 4390 | enum mc_target_type { |
8d32ff84 | 4391 | MC_TARGET_NONE = 0, |
4ffef5fe | 4392 | MC_TARGET_PAGE, |
02491447 | 4393 | MC_TARGET_SWAP, |
4ffef5fe DN |
4394 | }; |
4395 | ||
90254a65 DN |
4396 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
4397 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 4398 | { |
90254a65 | 4399 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 4400 | |
90254a65 DN |
4401 | if (!page || !page_mapped(page)) |
4402 | return NULL; | |
4403 | if (PageAnon(page)) { | |
1dfab5ab | 4404 | if (!(mc.flags & MOVE_ANON)) |
90254a65 | 4405 | return NULL; |
1dfab5ab JW |
4406 | } else { |
4407 | if (!(mc.flags & MOVE_FILE)) | |
4408 | return NULL; | |
4409 | } | |
90254a65 DN |
4410 | if (!get_page_unless_zero(page)) |
4411 | return NULL; | |
4412 | ||
4413 | return page; | |
4414 | } | |
4415 | ||
4b91355e | 4416 | #ifdef CONFIG_SWAP |
90254a65 | 4417 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, |
48406ef8 | 4418 | pte_t ptent, swp_entry_t *entry) |
90254a65 | 4419 | { |
90254a65 DN |
4420 | struct page *page = NULL; |
4421 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
4422 | ||
1dfab5ab | 4423 | if (!(mc.flags & MOVE_ANON) || non_swap_entry(ent)) |
90254a65 | 4424 | return NULL; |
4b91355e KH |
4425 | /* |
4426 | * Because lookup_swap_cache() updates some statistics counter, | |
4427 | * we call find_get_page() with swapper_space directly. | |
4428 | */ | |
f6ab1f7f | 4429 | page = find_get_page(swap_address_space(ent), swp_offset(ent)); |
7941d214 | 4430 | if (do_memsw_account()) |
90254a65 DN |
4431 | entry->val = ent.val; |
4432 | ||
4433 | return page; | |
4434 | } | |
4b91355e KH |
4435 | #else |
4436 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
48406ef8 | 4437 | pte_t ptent, swp_entry_t *entry) |
4b91355e KH |
4438 | { |
4439 | return NULL; | |
4440 | } | |
4441 | #endif | |
90254a65 | 4442 | |
87946a72 DN |
4443 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
4444 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
4445 | { | |
4446 | struct page *page = NULL; | |
87946a72 DN |
4447 | struct address_space *mapping; |
4448 | pgoff_t pgoff; | |
4449 | ||
4450 | if (!vma->vm_file) /* anonymous vma */ | |
4451 | return NULL; | |
1dfab5ab | 4452 | if (!(mc.flags & MOVE_FILE)) |
87946a72 DN |
4453 | return NULL; |
4454 | ||
87946a72 | 4455 | mapping = vma->vm_file->f_mapping; |
0661a336 | 4456 | pgoff = linear_page_index(vma, addr); |
87946a72 DN |
4457 | |
4458 | /* page is moved even if it's not RSS of this task(page-faulted). */ | |
aa3b1895 HD |
4459 | #ifdef CONFIG_SWAP |
4460 | /* shmem/tmpfs may report page out on swap: account for that too. */ | |
139b6a6f JW |
4461 | if (shmem_mapping(mapping)) { |
4462 | page = find_get_entry(mapping, pgoff); | |
4463 | if (radix_tree_exceptional_entry(page)) { | |
4464 | swp_entry_t swp = radix_to_swp_entry(page); | |
7941d214 | 4465 | if (do_memsw_account()) |
139b6a6f | 4466 | *entry = swp; |
f6ab1f7f HY |
4467 | page = find_get_page(swap_address_space(swp), |
4468 | swp_offset(swp)); | |
139b6a6f JW |
4469 | } |
4470 | } else | |
4471 | page = find_get_page(mapping, pgoff); | |
4472 | #else | |
4473 | page = find_get_page(mapping, pgoff); | |
aa3b1895 | 4474 | #endif |
87946a72 DN |
4475 | return page; |
4476 | } | |
4477 | ||
b1b0deab CG |
4478 | /** |
4479 | * mem_cgroup_move_account - move account of the page | |
4480 | * @page: the page | |
25843c2b | 4481 | * @compound: charge the page as compound or small page |
b1b0deab CG |
4482 | * @from: mem_cgroup which the page is moved from. |
4483 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
4484 | * | |
3ac808fd | 4485 | * The caller must make sure the page is not on LRU (isolate_page() is useful.) |
b1b0deab CG |
4486 | * |
4487 | * This function doesn't do "charge" to new cgroup and doesn't do "uncharge" | |
4488 | * from old cgroup. | |
4489 | */ | |
4490 | static int mem_cgroup_move_account(struct page *page, | |
f627c2f5 | 4491 | bool compound, |
b1b0deab CG |
4492 | struct mem_cgroup *from, |
4493 | struct mem_cgroup *to) | |
4494 | { | |
4495 | unsigned long flags; | |
f627c2f5 | 4496 | unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1; |
b1b0deab | 4497 | int ret; |
c4843a75 | 4498 | bool anon; |
b1b0deab CG |
4499 | |
4500 | VM_BUG_ON(from == to); | |
4501 | VM_BUG_ON_PAGE(PageLRU(page), page); | |
f627c2f5 | 4502 | VM_BUG_ON(compound && !PageTransHuge(page)); |
b1b0deab CG |
4503 | |
4504 | /* | |
6a93ca8f | 4505 | * Prevent mem_cgroup_migrate() from looking at |
45637bab | 4506 | * page->mem_cgroup of its source page while we change it. |
b1b0deab | 4507 | */ |
f627c2f5 | 4508 | ret = -EBUSY; |
b1b0deab CG |
4509 | if (!trylock_page(page)) |
4510 | goto out; | |
4511 | ||
4512 | ret = -EINVAL; | |
4513 | if (page->mem_cgroup != from) | |
4514 | goto out_unlock; | |
4515 | ||
c4843a75 GT |
4516 | anon = PageAnon(page); |
4517 | ||
b1b0deab CG |
4518 | spin_lock_irqsave(&from->move_lock, flags); |
4519 | ||
c4843a75 | 4520 | if (!anon && page_mapped(page)) { |
71cd3113 JW |
4521 | __this_cpu_sub(from->stat->count[NR_FILE_MAPPED], nr_pages); |
4522 | __this_cpu_add(to->stat->count[NR_FILE_MAPPED], nr_pages); | |
b1b0deab CG |
4523 | } |
4524 | ||
c4843a75 GT |
4525 | /* |
4526 | * move_lock grabbed above and caller set from->moving_account, so | |
ccda7f43 | 4527 | * mod_memcg_page_state will serialize updates to PageDirty. |
c4843a75 GT |
4528 | * So mapping should be stable for dirty pages. |
4529 | */ | |
4530 | if (!anon && PageDirty(page)) { | |
4531 | struct address_space *mapping = page_mapping(page); | |
4532 | ||
4533 | if (mapping_cap_account_dirty(mapping)) { | |
71cd3113 | 4534 | __this_cpu_sub(from->stat->count[NR_FILE_DIRTY], |
c4843a75 | 4535 | nr_pages); |
71cd3113 | 4536 | __this_cpu_add(to->stat->count[NR_FILE_DIRTY], |
c4843a75 GT |
4537 | nr_pages); |
4538 | } | |
4539 | } | |
4540 | ||
b1b0deab | 4541 | if (PageWriteback(page)) { |
71cd3113 JW |
4542 | __this_cpu_sub(from->stat->count[NR_WRITEBACK], nr_pages); |
4543 | __this_cpu_add(to->stat->count[NR_WRITEBACK], nr_pages); | |
b1b0deab CG |
4544 | } |
4545 | ||
4546 | /* | |
4547 | * It is safe to change page->mem_cgroup here because the page | |
4548 | * is referenced, charged, and isolated - we can't race with | |
4549 | * uncharging, charging, migration, or LRU putback. | |
4550 | */ | |
4551 | ||
4552 | /* caller should have done css_get */ | |
4553 | page->mem_cgroup = to; | |
4554 | spin_unlock_irqrestore(&from->move_lock, flags); | |
4555 | ||
4556 | ret = 0; | |
4557 | ||
4558 | local_irq_disable(); | |
f627c2f5 | 4559 | mem_cgroup_charge_statistics(to, page, compound, nr_pages); |
b1b0deab | 4560 | memcg_check_events(to, page); |
f627c2f5 | 4561 | mem_cgroup_charge_statistics(from, page, compound, -nr_pages); |
b1b0deab CG |
4562 | memcg_check_events(from, page); |
4563 | local_irq_enable(); | |
4564 | out_unlock: | |
4565 | unlock_page(page); | |
4566 | out: | |
4567 | return ret; | |
4568 | } | |
4569 | ||
7cf7806c LR |
4570 | /** |
4571 | * get_mctgt_type - get target type of moving charge | |
4572 | * @vma: the vma the pte to be checked belongs | |
4573 | * @addr: the address corresponding to the pte to be checked | |
4574 | * @ptent: the pte to be checked | |
4575 | * @target: the pointer the target page or swap ent will be stored(can be NULL) | |
4576 | * | |
4577 | * Returns | |
4578 | * 0(MC_TARGET_NONE): if the pte is not a target for move charge. | |
4579 | * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for | |
4580 | * move charge. if @target is not NULL, the page is stored in target->page | |
4581 | * with extra refcnt got(Callers should handle it). | |
4582 | * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a | |
4583 | * target for charge migration. if @target is not NULL, the entry is stored | |
4584 | * in target->ent. | |
4585 | * | |
4586 | * Called with pte lock held. | |
4587 | */ | |
4588 | ||
8d32ff84 | 4589 | static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, |
90254a65 DN |
4590 | unsigned long addr, pte_t ptent, union mc_target *target) |
4591 | { | |
4592 | struct page *page = NULL; | |
8d32ff84 | 4593 | enum mc_target_type ret = MC_TARGET_NONE; |
90254a65 DN |
4594 | swp_entry_t ent = { .val = 0 }; |
4595 | ||
4596 | if (pte_present(ptent)) | |
4597 | page = mc_handle_present_pte(vma, addr, ptent); | |
4598 | else if (is_swap_pte(ptent)) | |
48406ef8 | 4599 | page = mc_handle_swap_pte(vma, ptent, &ent); |
0661a336 | 4600 | else if (pte_none(ptent)) |
87946a72 | 4601 | page = mc_handle_file_pte(vma, addr, ptent, &ent); |
90254a65 DN |
4602 | |
4603 | if (!page && !ent.val) | |
8d32ff84 | 4604 | return ret; |
02491447 | 4605 | if (page) { |
02491447 | 4606 | /* |
0a31bc97 | 4607 | * Do only loose check w/o serialization. |
1306a85a | 4608 | * mem_cgroup_move_account() checks the page is valid or |
0a31bc97 | 4609 | * not under LRU exclusion. |
02491447 | 4610 | */ |
1306a85a | 4611 | if (page->mem_cgroup == mc.from) { |
02491447 DN |
4612 | ret = MC_TARGET_PAGE; |
4613 | if (target) | |
4614 | target->page = page; | |
4615 | } | |
4616 | if (!ret || !target) | |
4617 | put_page(page); | |
4618 | } | |
90254a65 DN |
4619 | /* There is a swap entry and a page doesn't exist or isn't charged */ |
4620 | if (ent.val && !ret && | |
34c00c31 | 4621 | mem_cgroup_id(mc.from) == lookup_swap_cgroup_id(ent)) { |
7f0f1546 KH |
4622 | ret = MC_TARGET_SWAP; |
4623 | if (target) | |
4624 | target->ent = ent; | |
4ffef5fe | 4625 | } |
4ffef5fe DN |
4626 | return ret; |
4627 | } | |
4628 | ||
12724850 NH |
4629 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
4630 | /* | |
4631 | * We don't consider swapping or file mapped pages because THP does not | |
4632 | * support them for now. | |
4633 | * Caller should make sure that pmd_trans_huge(pmd) is true. | |
4634 | */ | |
4635 | static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
4636 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
4637 | { | |
4638 | struct page *page = NULL; | |
12724850 NH |
4639 | enum mc_target_type ret = MC_TARGET_NONE; |
4640 | ||
4641 | page = pmd_page(pmd); | |
309381fe | 4642 | VM_BUG_ON_PAGE(!page || !PageHead(page), page); |
1dfab5ab | 4643 | if (!(mc.flags & MOVE_ANON)) |
12724850 | 4644 | return ret; |
1306a85a | 4645 | if (page->mem_cgroup == mc.from) { |
12724850 NH |
4646 | ret = MC_TARGET_PAGE; |
4647 | if (target) { | |
4648 | get_page(page); | |
4649 | target->page = page; | |
4650 | } | |
4651 | } | |
4652 | return ret; | |
4653 | } | |
4654 | #else | |
4655 | static inline enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
4656 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
4657 | { | |
4658 | return MC_TARGET_NONE; | |
4659 | } | |
4660 | #endif | |
4661 | ||
4ffef5fe DN |
4662 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, |
4663 | unsigned long addr, unsigned long end, | |
4664 | struct mm_walk *walk) | |
4665 | { | |
26bcd64a | 4666 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
4667 | pte_t *pte; |
4668 | spinlock_t *ptl; | |
4669 | ||
b6ec57f4 KS |
4670 | ptl = pmd_trans_huge_lock(pmd, vma); |
4671 | if (ptl) { | |
12724850 NH |
4672 | if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE) |
4673 | mc.precharge += HPAGE_PMD_NR; | |
bf929152 | 4674 | spin_unlock(ptl); |
1a5a9906 | 4675 | return 0; |
12724850 | 4676 | } |
03319327 | 4677 | |
45f83cef AA |
4678 | if (pmd_trans_unstable(pmd)) |
4679 | return 0; | |
4ffef5fe DN |
4680 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
4681 | for (; addr != end; pte++, addr += PAGE_SIZE) | |
8d32ff84 | 4682 | if (get_mctgt_type(vma, addr, *pte, NULL)) |
4ffef5fe DN |
4683 | mc.precharge++; /* increment precharge temporarily */ |
4684 | pte_unmap_unlock(pte - 1, ptl); | |
4685 | cond_resched(); | |
4686 | ||
7dc74be0 DN |
4687 | return 0; |
4688 | } | |
4689 | ||
4ffef5fe DN |
4690 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
4691 | { | |
4692 | unsigned long precharge; | |
4ffef5fe | 4693 | |
26bcd64a NH |
4694 | struct mm_walk mem_cgroup_count_precharge_walk = { |
4695 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
4696 | .mm = mm, | |
4697 | }; | |
dfe076b0 | 4698 | down_read(&mm->mmap_sem); |
0247f3f4 JM |
4699 | walk_page_range(0, mm->highest_vm_end, |
4700 | &mem_cgroup_count_precharge_walk); | |
dfe076b0 | 4701 | up_read(&mm->mmap_sem); |
4ffef5fe DN |
4702 | |
4703 | precharge = mc.precharge; | |
4704 | mc.precharge = 0; | |
4705 | ||
4706 | return precharge; | |
4707 | } | |
4708 | ||
4ffef5fe DN |
4709 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
4710 | { | |
dfe076b0 DN |
4711 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
4712 | ||
4713 | VM_BUG_ON(mc.moving_task); | |
4714 | mc.moving_task = current; | |
4715 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
4716 | } |
4717 | ||
dfe076b0 DN |
4718 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
4719 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 4720 | { |
2bd9bb20 KH |
4721 | struct mem_cgroup *from = mc.from; |
4722 | struct mem_cgroup *to = mc.to; | |
4723 | ||
4ffef5fe | 4724 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d | 4725 | if (mc.precharge) { |
00501b53 | 4726 | cancel_charge(mc.to, mc.precharge); |
854ffa8d DN |
4727 | mc.precharge = 0; |
4728 | } | |
4729 | /* | |
4730 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
4731 | * we must uncharge here. | |
4732 | */ | |
4733 | if (mc.moved_charge) { | |
00501b53 | 4734 | cancel_charge(mc.from, mc.moved_charge); |
854ffa8d | 4735 | mc.moved_charge = 0; |
4ffef5fe | 4736 | } |
483c30b5 DN |
4737 | /* we must fixup refcnts and charges */ |
4738 | if (mc.moved_swap) { | |
483c30b5 | 4739 | /* uncharge swap account from the old cgroup */ |
ce00a967 | 4740 | if (!mem_cgroup_is_root(mc.from)) |
3e32cb2e | 4741 | page_counter_uncharge(&mc.from->memsw, mc.moved_swap); |
483c30b5 | 4742 | |
615d66c3 VD |
4743 | mem_cgroup_id_put_many(mc.from, mc.moved_swap); |
4744 | ||
05b84301 | 4745 | /* |
3e32cb2e JW |
4746 | * we charged both to->memory and to->memsw, so we |
4747 | * should uncharge to->memory. | |
05b84301 | 4748 | */ |
ce00a967 | 4749 | if (!mem_cgroup_is_root(mc.to)) |
3e32cb2e JW |
4750 | page_counter_uncharge(&mc.to->memory, mc.moved_swap); |
4751 | ||
615d66c3 VD |
4752 | mem_cgroup_id_get_many(mc.to, mc.moved_swap); |
4753 | css_put_many(&mc.to->css, mc.moved_swap); | |
3e32cb2e | 4754 | |
483c30b5 DN |
4755 | mc.moved_swap = 0; |
4756 | } | |
dfe076b0 DN |
4757 | memcg_oom_recover(from); |
4758 | memcg_oom_recover(to); | |
4759 | wake_up_all(&mc.waitq); | |
4760 | } | |
4761 | ||
4762 | static void mem_cgroup_clear_mc(void) | |
4763 | { | |
264a0ae1 TH |
4764 | struct mm_struct *mm = mc.mm; |
4765 | ||
dfe076b0 DN |
4766 | /* |
4767 | * we must clear moving_task before waking up waiters at the end of | |
4768 | * task migration. | |
4769 | */ | |
4770 | mc.moving_task = NULL; | |
4771 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 4772 | spin_lock(&mc.lock); |
4ffef5fe DN |
4773 | mc.from = NULL; |
4774 | mc.to = NULL; | |
264a0ae1 | 4775 | mc.mm = NULL; |
2bd9bb20 | 4776 | spin_unlock(&mc.lock); |
264a0ae1 TH |
4777 | |
4778 | mmput(mm); | |
4ffef5fe DN |
4779 | } |
4780 | ||
1f7dd3e5 | 4781 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
7dc74be0 | 4782 | { |
1f7dd3e5 | 4783 | struct cgroup_subsys_state *css; |
eed67d75 | 4784 | struct mem_cgroup *memcg = NULL; /* unneeded init to make gcc happy */ |
9f2115f9 | 4785 | struct mem_cgroup *from; |
4530eddb | 4786 | struct task_struct *leader, *p; |
9f2115f9 | 4787 | struct mm_struct *mm; |
1dfab5ab | 4788 | unsigned long move_flags; |
9f2115f9 | 4789 | int ret = 0; |
7dc74be0 | 4790 | |
1f7dd3e5 TH |
4791 | /* charge immigration isn't supported on the default hierarchy */ |
4792 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
9f2115f9 TH |
4793 | return 0; |
4794 | ||
4530eddb TH |
4795 | /* |
4796 | * Multi-process migrations only happen on the default hierarchy | |
4797 | * where charge immigration is not used. Perform charge | |
4798 | * immigration if @tset contains a leader and whine if there are | |
4799 | * multiple. | |
4800 | */ | |
4801 | p = NULL; | |
1f7dd3e5 | 4802 | cgroup_taskset_for_each_leader(leader, css, tset) { |
4530eddb TH |
4803 | WARN_ON_ONCE(p); |
4804 | p = leader; | |
1f7dd3e5 | 4805 | memcg = mem_cgroup_from_css(css); |
4530eddb TH |
4806 | } |
4807 | if (!p) | |
4808 | return 0; | |
4809 | ||
1f7dd3e5 TH |
4810 | /* |
4811 | * We are now commited to this value whatever it is. Changes in this | |
4812 | * tunable will only affect upcoming migrations, not the current one. | |
4813 | * So we need to save it, and keep it going. | |
4814 | */ | |
4815 | move_flags = READ_ONCE(memcg->move_charge_at_immigrate); | |
4816 | if (!move_flags) | |
4817 | return 0; | |
4818 | ||
9f2115f9 TH |
4819 | from = mem_cgroup_from_task(p); |
4820 | ||
4821 | VM_BUG_ON(from == memcg); | |
4822 | ||
4823 | mm = get_task_mm(p); | |
4824 | if (!mm) | |
4825 | return 0; | |
4826 | /* We move charges only when we move a owner of the mm */ | |
4827 | if (mm->owner == p) { | |
4828 | VM_BUG_ON(mc.from); | |
4829 | VM_BUG_ON(mc.to); | |
4830 | VM_BUG_ON(mc.precharge); | |
4831 | VM_BUG_ON(mc.moved_charge); | |
4832 | VM_BUG_ON(mc.moved_swap); | |
4833 | ||
4834 | spin_lock(&mc.lock); | |
264a0ae1 | 4835 | mc.mm = mm; |
9f2115f9 TH |
4836 | mc.from = from; |
4837 | mc.to = memcg; | |
4838 | mc.flags = move_flags; | |
4839 | spin_unlock(&mc.lock); | |
4840 | /* We set mc.moving_task later */ | |
4841 | ||
4842 | ret = mem_cgroup_precharge_mc(mm); | |
4843 | if (ret) | |
4844 | mem_cgroup_clear_mc(); | |
264a0ae1 TH |
4845 | } else { |
4846 | mmput(mm); | |
7dc74be0 DN |
4847 | } |
4848 | return ret; | |
4849 | } | |
4850 | ||
1f7dd3e5 | 4851 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
7dc74be0 | 4852 | { |
4e2f245d JW |
4853 | if (mc.to) |
4854 | mem_cgroup_clear_mc(); | |
7dc74be0 DN |
4855 | } |
4856 | ||
4ffef5fe DN |
4857 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
4858 | unsigned long addr, unsigned long end, | |
4859 | struct mm_walk *walk) | |
7dc74be0 | 4860 | { |
4ffef5fe | 4861 | int ret = 0; |
26bcd64a | 4862 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
4863 | pte_t *pte; |
4864 | spinlock_t *ptl; | |
12724850 NH |
4865 | enum mc_target_type target_type; |
4866 | union mc_target target; | |
4867 | struct page *page; | |
4ffef5fe | 4868 | |
b6ec57f4 KS |
4869 | ptl = pmd_trans_huge_lock(pmd, vma); |
4870 | if (ptl) { | |
62ade86a | 4871 | if (mc.precharge < HPAGE_PMD_NR) { |
bf929152 | 4872 | spin_unlock(ptl); |
12724850 NH |
4873 | return 0; |
4874 | } | |
4875 | target_type = get_mctgt_type_thp(vma, addr, *pmd, &target); | |
4876 | if (target_type == MC_TARGET_PAGE) { | |
4877 | page = target.page; | |
4878 | if (!isolate_lru_page(page)) { | |
f627c2f5 | 4879 | if (!mem_cgroup_move_account(page, true, |
1306a85a | 4880 | mc.from, mc.to)) { |
12724850 NH |
4881 | mc.precharge -= HPAGE_PMD_NR; |
4882 | mc.moved_charge += HPAGE_PMD_NR; | |
4883 | } | |
4884 | putback_lru_page(page); | |
4885 | } | |
4886 | put_page(page); | |
4887 | } | |
bf929152 | 4888 | spin_unlock(ptl); |
1a5a9906 | 4889 | return 0; |
12724850 NH |
4890 | } |
4891 | ||
45f83cef AA |
4892 | if (pmd_trans_unstable(pmd)) |
4893 | return 0; | |
4ffef5fe DN |
4894 | retry: |
4895 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
4896 | for (; addr != end; addr += PAGE_SIZE) { | |
4897 | pte_t ptent = *(pte++); | |
02491447 | 4898 | swp_entry_t ent; |
4ffef5fe DN |
4899 | |
4900 | if (!mc.precharge) | |
4901 | break; | |
4902 | ||
8d32ff84 | 4903 | switch (get_mctgt_type(vma, addr, ptent, &target)) { |
4ffef5fe DN |
4904 | case MC_TARGET_PAGE: |
4905 | page = target.page; | |
53f9263b KS |
4906 | /* |
4907 | * We can have a part of the split pmd here. Moving it | |
4908 | * can be done but it would be too convoluted so simply | |
4909 | * ignore such a partial THP and keep it in original | |
4910 | * memcg. There should be somebody mapping the head. | |
4911 | */ | |
4912 | if (PageTransCompound(page)) | |
4913 | goto put; | |
4ffef5fe DN |
4914 | if (isolate_lru_page(page)) |
4915 | goto put; | |
f627c2f5 KS |
4916 | if (!mem_cgroup_move_account(page, false, |
4917 | mc.from, mc.to)) { | |
4ffef5fe | 4918 | mc.precharge--; |
854ffa8d DN |
4919 | /* we uncharge from mc.from later. */ |
4920 | mc.moved_charge++; | |
4ffef5fe DN |
4921 | } |
4922 | putback_lru_page(page); | |
8d32ff84 | 4923 | put: /* get_mctgt_type() gets the page */ |
4ffef5fe DN |
4924 | put_page(page); |
4925 | break; | |
02491447 DN |
4926 | case MC_TARGET_SWAP: |
4927 | ent = target.ent; | |
e91cbb42 | 4928 | if (!mem_cgroup_move_swap_account(ent, mc.from, mc.to)) { |
02491447 | 4929 | mc.precharge--; |
483c30b5 DN |
4930 | /* we fixup refcnts and charges later. */ |
4931 | mc.moved_swap++; | |
4932 | } | |
02491447 | 4933 | break; |
4ffef5fe DN |
4934 | default: |
4935 | break; | |
4936 | } | |
4937 | } | |
4938 | pte_unmap_unlock(pte - 1, ptl); | |
4939 | cond_resched(); | |
4940 | ||
4941 | if (addr != end) { | |
4942 | /* | |
4943 | * We have consumed all precharges we got in can_attach(). | |
4944 | * We try charge one by one, but don't do any additional | |
4945 | * charges to mc.to if we have failed in charge once in attach() | |
4946 | * phase. | |
4947 | */ | |
854ffa8d | 4948 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
4949 | if (!ret) |
4950 | goto retry; | |
4951 | } | |
4952 | ||
4953 | return ret; | |
4954 | } | |
4955 | ||
264a0ae1 | 4956 | static void mem_cgroup_move_charge(void) |
4ffef5fe | 4957 | { |
26bcd64a NH |
4958 | struct mm_walk mem_cgroup_move_charge_walk = { |
4959 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
264a0ae1 | 4960 | .mm = mc.mm, |
26bcd64a | 4961 | }; |
4ffef5fe DN |
4962 | |
4963 | lru_add_drain_all(); | |
312722cb | 4964 | /* |
81f8c3a4 JW |
4965 | * Signal lock_page_memcg() to take the memcg's move_lock |
4966 | * while we're moving its pages to another memcg. Then wait | |
4967 | * for already started RCU-only updates to finish. | |
312722cb JW |
4968 | */ |
4969 | atomic_inc(&mc.from->moving_account); | |
4970 | synchronize_rcu(); | |
dfe076b0 | 4971 | retry: |
264a0ae1 | 4972 | if (unlikely(!down_read_trylock(&mc.mm->mmap_sem))) { |
dfe076b0 DN |
4973 | /* |
4974 | * Someone who are holding the mmap_sem might be waiting in | |
4975 | * waitq. So we cancel all extra charges, wake up all waiters, | |
4976 | * and retry. Because we cancel precharges, we might not be able | |
4977 | * to move enough charges, but moving charge is a best-effort | |
4978 | * feature anyway, so it wouldn't be a big problem. | |
4979 | */ | |
4980 | __mem_cgroup_clear_mc(); | |
4981 | cond_resched(); | |
4982 | goto retry; | |
4983 | } | |
26bcd64a NH |
4984 | /* |
4985 | * When we have consumed all precharges and failed in doing | |
4986 | * additional charge, the page walk just aborts. | |
4987 | */ | |
0247f3f4 JM |
4988 | walk_page_range(0, mc.mm->highest_vm_end, &mem_cgroup_move_charge_walk); |
4989 | ||
264a0ae1 | 4990 | up_read(&mc.mm->mmap_sem); |
312722cb | 4991 | atomic_dec(&mc.from->moving_account); |
7dc74be0 DN |
4992 | } |
4993 | ||
264a0ae1 | 4994 | static void mem_cgroup_move_task(void) |
67e465a7 | 4995 | { |
264a0ae1 TH |
4996 | if (mc.to) { |
4997 | mem_cgroup_move_charge(); | |
a433658c | 4998 | mem_cgroup_clear_mc(); |
264a0ae1 | 4999 | } |
67e465a7 | 5000 | } |
5cfb80a7 | 5001 | #else /* !CONFIG_MMU */ |
1f7dd3e5 | 5002 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
5003 | { |
5004 | return 0; | |
5005 | } | |
1f7dd3e5 | 5006 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
5007 | { |
5008 | } | |
264a0ae1 | 5009 | static void mem_cgroup_move_task(void) |
5cfb80a7 DN |
5010 | { |
5011 | } | |
5012 | #endif | |
67e465a7 | 5013 | |
f00baae7 TH |
5014 | /* |
5015 | * Cgroup retains root cgroups across [un]mount cycles making it necessary | |
aa6ec29b TH |
5016 | * to verify whether we're attached to the default hierarchy on each mount |
5017 | * attempt. | |
f00baae7 | 5018 | */ |
eb95419b | 5019 | static void mem_cgroup_bind(struct cgroup_subsys_state *root_css) |
f00baae7 TH |
5020 | { |
5021 | /* | |
aa6ec29b | 5022 | * use_hierarchy is forced on the default hierarchy. cgroup core |
f00baae7 TH |
5023 | * guarantees that @root doesn't have any children, so turning it |
5024 | * on for the root memcg is enough. | |
5025 | */ | |
9e10a130 | 5026 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
7feee590 VD |
5027 | root_mem_cgroup->use_hierarchy = true; |
5028 | else | |
5029 | root_mem_cgroup->use_hierarchy = false; | |
f00baae7 TH |
5030 | } |
5031 | ||
241994ed JW |
5032 | static u64 memory_current_read(struct cgroup_subsys_state *css, |
5033 | struct cftype *cft) | |
5034 | { | |
f5fc3c5d JW |
5035 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
5036 | ||
5037 | return (u64)page_counter_read(&memcg->memory) * PAGE_SIZE; | |
241994ed JW |
5038 | } |
5039 | ||
5040 | static int memory_low_show(struct seq_file *m, void *v) | |
5041 | { | |
5042 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); | |
4db0c3c2 | 5043 | unsigned long low = READ_ONCE(memcg->low); |
241994ed JW |
5044 | |
5045 | if (low == PAGE_COUNTER_MAX) | |
d2973697 | 5046 | seq_puts(m, "max\n"); |
241994ed JW |
5047 | else |
5048 | seq_printf(m, "%llu\n", (u64)low * PAGE_SIZE); | |
5049 | ||
5050 | return 0; | |
5051 | } | |
5052 | ||
5053 | static ssize_t memory_low_write(struct kernfs_open_file *of, | |
5054 | char *buf, size_t nbytes, loff_t off) | |
5055 | { | |
5056 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
5057 | unsigned long low; | |
5058 | int err; | |
5059 | ||
5060 | buf = strstrip(buf); | |
d2973697 | 5061 | err = page_counter_memparse(buf, "max", &low); |
241994ed JW |
5062 | if (err) |
5063 | return err; | |
5064 | ||
5065 | memcg->low = low; | |
5066 | ||
5067 | return nbytes; | |
5068 | } | |
5069 | ||
5070 | static int memory_high_show(struct seq_file *m, void *v) | |
5071 | { | |
5072 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); | |
4db0c3c2 | 5073 | unsigned long high = READ_ONCE(memcg->high); |
241994ed JW |
5074 | |
5075 | if (high == PAGE_COUNTER_MAX) | |
d2973697 | 5076 | seq_puts(m, "max\n"); |
241994ed JW |
5077 | else |
5078 | seq_printf(m, "%llu\n", (u64)high * PAGE_SIZE); | |
5079 | ||
5080 | return 0; | |
5081 | } | |
5082 | ||
5083 | static ssize_t memory_high_write(struct kernfs_open_file *of, | |
5084 | char *buf, size_t nbytes, loff_t off) | |
5085 | { | |
5086 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
588083bb | 5087 | unsigned long nr_pages; |
241994ed JW |
5088 | unsigned long high; |
5089 | int err; | |
5090 | ||
5091 | buf = strstrip(buf); | |
d2973697 | 5092 | err = page_counter_memparse(buf, "max", &high); |
241994ed JW |
5093 | if (err) |
5094 | return err; | |
5095 | ||
5096 | memcg->high = high; | |
5097 | ||
588083bb JW |
5098 | nr_pages = page_counter_read(&memcg->memory); |
5099 | if (nr_pages > high) | |
5100 | try_to_free_mem_cgroup_pages(memcg, nr_pages - high, | |
5101 | GFP_KERNEL, true); | |
5102 | ||
2529bb3a | 5103 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
5104 | return nbytes; |
5105 | } | |
5106 | ||
5107 | static int memory_max_show(struct seq_file *m, void *v) | |
5108 | { | |
5109 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); | |
4db0c3c2 | 5110 | unsigned long max = READ_ONCE(memcg->memory.limit); |
241994ed JW |
5111 | |
5112 | if (max == PAGE_COUNTER_MAX) | |
d2973697 | 5113 | seq_puts(m, "max\n"); |
241994ed JW |
5114 | else |
5115 | seq_printf(m, "%llu\n", (u64)max * PAGE_SIZE); | |
5116 | ||
5117 | return 0; | |
5118 | } | |
5119 | ||
5120 | static ssize_t memory_max_write(struct kernfs_open_file *of, | |
5121 | char *buf, size_t nbytes, loff_t off) | |
5122 | { | |
5123 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
b6e6edcf JW |
5124 | unsigned int nr_reclaims = MEM_CGROUP_RECLAIM_RETRIES; |
5125 | bool drained = false; | |
241994ed JW |
5126 | unsigned long max; |
5127 | int err; | |
5128 | ||
5129 | buf = strstrip(buf); | |
d2973697 | 5130 | err = page_counter_memparse(buf, "max", &max); |
241994ed JW |
5131 | if (err) |
5132 | return err; | |
5133 | ||
b6e6edcf JW |
5134 | xchg(&memcg->memory.limit, max); |
5135 | ||
5136 | for (;;) { | |
5137 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
5138 | ||
5139 | if (nr_pages <= max) | |
5140 | break; | |
5141 | ||
5142 | if (signal_pending(current)) { | |
5143 | err = -EINTR; | |
5144 | break; | |
5145 | } | |
5146 | ||
5147 | if (!drained) { | |
5148 | drain_all_stock(memcg); | |
5149 | drained = true; | |
5150 | continue; | |
5151 | } | |
5152 | ||
5153 | if (nr_reclaims) { | |
5154 | if (!try_to_free_mem_cgroup_pages(memcg, nr_pages - max, | |
5155 | GFP_KERNEL, true)) | |
5156 | nr_reclaims--; | |
5157 | continue; | |
5158 | } | |
5159 | ||
31176c78 | 5160 | mem_cgroup_event(memcg, MEMCG_OOM); |
b6e6edcf JW |
5161 | if (!mem_cgroup_out_of_memory(memcg, GFP_KERNEL, 0)) |
5162 | break; | |
5163 | } | |
241994ed | 5164 | |
2529bb3a | 5165 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
5166 | return nbytes; |
5167 | } | |
5168 | ||
5169 | static int memory_events_show(struct seq_file *m, void *v) | |
5170 | { | |
5171 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); | |
5172 | ||
ccda7f43 JW |
5173 | seq_printf(m, "low %lu\n", memcg_sum_events(memcg, MEMCG_LOW)); |
5174 | seq_printf(m, "high %lu\n", memcg_sum_events(memcg, MEMCG_HIGH)); | |
5175 | seq_printf(m, "max %lu\n", memcg_sum_events(memcg, MEMCG_MAX)); | |
5176 | seq_printf(m, "oom %lu\n", memcg_sum_events(memcg, MEMCG_OOM)); | |
8e675f7a | 5177 | seq_printf(m, "oom_kill %lu\n", memcg_sum_events(memcg, OOM_KILL)); |
241994ed JW |
5178 | |
5179 | return 0; | |
5180 | } | |
5181 | ||
587d9f72 JW |
5182 | static int memory_stat_show(struct seq_file *m, void *v) |
5183 | { | |
5184 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); | |
72b54e73 VD |
5185 | unsigned long stat[MEMCG_NR_STAT]; |
5186 | unsigned long events[MEMCG_NR_EVENTS]; | |
587d9f72 JW |
5187 | int i; |
5188 | ||
5189 | /* | |
5190 | * Provide statistics on the state of the memory subsystem as | |
5191 | * well as cumulative event counters that show past behavior. | |
5192 | * | |
5193 | * This list is ordered following a combination of these gradients: | |
5194 | * 1) generic big picture -> specifics and details | |
5195 | * 2) reflecting userspace activity -> reflecting kernel heuristics | |
5196 | * | |
5197 | * Current memory state: | |
5198 | */ | |
5199 | ||
72b54e73 VD |
5200 | tree_stat(memcg, stat); |
5201 | tree_events(memcg, events); | |
5202 | ||
587d9f72 | 5203 | seq_printf(m, "anon %llu\n", |
71cd3113 | 5204 | (u64)stat[MEMCG_RSS] * PAGE_SIZE); |
587d9f72 | 5205 | seq_printf(m, "file %llu\n", |
71cd3113 | 5206 | (u64)stat[MEMCG_CACHE] * PAGE_SIZE); |
12580e4b | 5207 | seq_printf(m, "kernel_stack %llu\n", |
efdc9490 | 5208 | (u64)stat[MEMCG_KERNEL_STACK_KB] * 1024); |
27ee57c9 | 5209 | seq_printf(m, "slab %llu\n", |
32049296 JW |
5210 | (u64)(stat[NR_SLAB_RECLAIMABLE] + |
5211 | stat[NR_SLAB_UNRECLAIMABLE]) * PAGE_SIZE); | |
b2807f07 | 5212 | seq_printf(m, "sock %llu\n", |
72b54e73 | 5213 | (u64)stat[MEMCG_SOCK] * PAGE_SIZE); |
587d9f72 | 5214 | |
9a4caf1e | 5215 | seq_printf(m, "shmem %llu\n", |
71cd3113 | 5216 | (u64)stat[NR_SHMEM] * PAGE_SIZE); |
587d9f72 | 5217 | seq_printf(m, "file_mapped %llu\n", |
71cd3113 | 5218 | (u64)stat[NR_FILE_MAPPED] * PAGE_SIZE); |
587d9f72 | 5219 | seq_printf(m, "file_dirty %llu\n", |
71cd3113 | 5220 | (u64)stat[NR_FILE_DIRTY] * PAGE_SIZE); |
587d9f72 | 5221 | seq_printf(m, "file_writeback %llu\n", |
71cd3113 | 5222 | (u64)stat[NR_WRITEBACK] * PAGE_SIZE); |
587d9f72 JW |
5223 | |
5224 | for (i = 0; i < NR_LRU_LISTS; i++) { | |
5225 | struct mem_cgroup *mi; | |
5226 | unsigned long val = 0; | |
5227 | ||
5228 | for_each_mem_cgroup_tree(mi, memcg) | |
5229 | val += mem_cgroup_nr_lru_pages(mi, BIT(i)); | |
5230 | seq_printf(m, "%s %llu\n", | |
5231 | mem_cgroup_lru_names[i], (u64)val * PAGE_SIZE); | |
5232 | } | |
5233 | ||
27ee57c9 | 5234 | seq_printf(m, "slab_reclaimable %llu\n", |
32049296 | 5235 | (u64)stat[NR_SLAB_RECLAIMABLE] * PAGE_SIZE); |
27ee57c9 | 5236 | seq_printf(m, "slab_unreclaimable %llu\n", |
32049296 | 5237 | (u64)stat[NR_SLAB_UNRECLAIMABLE] * PAGE_SIZE); |
27ee57c9 | 5238 | |
587d9f72 JW |
5239 | /* Accumulated memory events */ |
5240 | ||
df0e53d0 JW |
5241 | seq_printf(m, "pgfault %lu\n", events[PGFAULT]); |
5242 | seq_printf(m, "pgmajfault %lu\n", events[PGMAJFAULT]); | |
587d9f72 | 5243 | |
2262185c RG |
5244 | seq_printf(m, "pgrefill %lu\n", events[PGREFILL]); |
5245 | seq_printf(m, "pgscan %lu\n", events[PGSCAN_KSWAPD] + | |
5246 | events[PGSCAN_DIRECT]); | |
5247 | seq_printf(m, "pgsteal %lu\n", events[PGSTEAL_KSWAPD] + | |
5248 | events[PGSTEAL_DIRECT]); | |
5249 | seq_printf(m, "pgactivate %lu\n", events[PGACTIVATE]); | |
5250 | seq_printf(m, "pgdeactivate %lu\n", events[PGDEACTIVATE]); | |
5251 | seq_printf(m, "pglazyfree %lu\n", events[PGLAZYFREE]); | |
5252 | seq_printf(m, "pglazyfreed %lu\n", events[PGLAZYFREED]); | |
5253 | ||
2a2e4885 | 5254 | seq_printf(m, "workingset_refault %lu\n", |
71cd3113 | 5255 | stat[WORKINGSET_REFAULT]); |
2a2e4885 | 5256 | seq_printf(m, "workingset_activate %lu\n", |
71cd3113 | 5257 | stat[WORKINGSET_ACTIVATE]); |
2a2e4885 | 5258 | seq_printf(m, "workingset_nodereclaim %lu\n", |
71cd3113 | 5259 | stat[WORKINGSET_NODERECLAIM]); |
2a2e4885 | 5260 | |
587d9f72 JW |
5261 | return 0; |
5262 | } | |
5263 | ||
241994ed JW |
5264 | static struct cftype memory_files[] = { |
5265 | { | |
5266 | .name = "current", | |
f5fc3c5d | 5267 | .flags = CFTYPE_NOT_ON_ROOT, |
241994ed JW |
5268 | .read_u64 = memory_current_read, |
5269 | }, | |
5270 | { | |
5271 | .name = "low", | |
5272 | .flags = CFTYPE_NOT_ON_ROOT, | |
5273 | .seq_show = memory_low_show, | |
5274 | .write = memory_low_write, | |
5275 | }, | |
5276 | { | |
5277 | .name = "high", | |
5278 | .flags = CFTYPE_NOT_ON_ROOT, | |
5279 | .seq_show = memory_high_show, | |
5280 | .write = memory_high_write, | |
5281 | }, | |
5282 | { | |
5283 | .name = "max", | |
5284 | .flags = CFTYPE_NOT_ON_ROOT, | |
5285 | .seq_show = memory_max_show, | |
5286 | .write = memory_max_write, | |
5287 | }, | |
5288 | { | |
5289 | .name = "events", | |
5290 | .flags = CFTYPE_NOT_ON_ROOT, | |
472912a2 | 5291 | .file_offset = offsetof(struct mem_cgroup, events_file), |
241994ed JW |
5292 | .seq_show = memory_events_show, |
5293 | }, | |
587d9f72 JW |
5294 | { |
5295 | .name = "stat", | |
5296 | .flags = CFTYPE_NOT_ON_ROOT, | |
5297 | .seq_show = memory_stat_show, | |
5298 | }, | |
241994ed JW |
5299 | { } /* terminate */ |
5300 | }; | |
5301 | ||
073219e9 | 5302 | struct cgroup_subsys memory_cgrp_subsys = { |
92fb9748 | 5303 | .css_alloc = mem_cgroup_css_alloc, |
d142e3e6 | 5304 | .css_online = mem_cgroup_css_online, |
92fb9748 | 5305 | .css_offline = mem_cgroup_css_offline, |
6df38689 | 5306 | .css_released = mem_cgroup_css_released, |
92fb9748 | 5307 | .css_free = mem_cgroup_css_free, |
1ced953b | 5308 | .css_reset = mem_cgroup_css_reset, |
7dc74be0 DN |
5309 | .can_attach = mem_cgroup_can_attach, |
5310 | .cancel_attach = mem_cgroup_cancel_attach, | |
264a0ae1 | 5311 | .post_attach = mem_cgroup_move_task, |
f00baae7 | 5312 | .bind = mem_cgroup_bind, |
241994ed JW |
5313 | .dfl_cftypes = memory_files, |
5314 | .legacy_cftypes = mem_cgroup_legacy_files, | |
6d12e2d8 | 5315 | .early_init = 0, |
8cdea7c0 | 5316 | }; |
c077719b | 5317 | |
241994ed JW |
5318 | /** |
5319 | * mem_cgroup_low - check if memory consumption is below the normal range | |
34c81057 | 5320 | * @root: the top ancestor of the sub-tree being checked |
241994ed JW |
5321 | * @memcg: the memory cgroup to check |
5322 | * | |
5323 | * Returns %true if memory consumption of @memcg, and that of all | |
34c81057 SC |
5324 | * ancestors up to (but not including) @root, is below the normal range. |
5325 | * | |
5326 | * @root is exclusive; it is never low when looked at directly and isn't | |
5327 | * checked when traversing the hierarchy. | |
5328 | * | |
5329 | * Excluding @root enables using memory.low to prioritize memory usage | |
5330 | * between cgroups within a subtree of the hierarchy that is limited by | |
5331 | * memory.high or memory.max. | |
5332 | * | |
5333 | * For example, given cgroup A with children B and C: | |
5334 | * | |
5335 | * A | |
5336 | * / \ | |
5337 | * B C | |
5338 | * | |
5339 | * and | |
5340 | * | |
5341 | * 1. A/memory.current > A/memory.high | |
5342 | * 2. A/B/memory.current < A/B/memory.low | |
5343 | * 3. A/C/memory.current >= A/C/memory.low | |
5344 | * | |
5345 | * As 'A' is high, i.e. triggers reclaim from 'A', and 'B' is low, we | |
5346 | * should reclaim from 'C' until 'A' is no longer high or until we can | |
5347 | * no longer reclaim from 'C'. If 'A', i.e. @root, isn't excluded by | |
5348 | * mem_cgroup_low when reclaming from 'A', then 'B' won't be considered | |
5349 | * low and we will reclaim indiscriminately from both 'B' and 'C'. | |
241994ed JW |
5350 | */ |
5351 | bool mem_cgroup_low(struct mem_cgroup *root, struct mem_cgroup *memcg) | |
5352 | { | |
5353 | if (mem_cgroup_disabled()) | |
5354 | return false; | |
5355 | ||
34c81057 SC |
5356 | if (!root) |
5357 | root = root_mem_cgroup; | |
5358 | if (memcg == root) | |
241994ed JW |
5359 | return false; |
5360 | ||
34c81057 | 5361 | for (; memcg != root; memcg = parent_mem_cgroup(memcg)) { |
4e54dede | 5362 | if (page_counter_read(&memcg->memory) >= memcg->low) |
241994ed JW |
5363 | return false; |
5364 | } | |
34c81057 | 5365 | |
241994ed JW |
5366 | return true; |
5367 | } | |
5368 | ||
00501b53 JW |
5369 | /** |
5370 | * mem_cgroup_try_charge - try charging a page | |
5371 | * @page: page to charge | |
5372 | * @mm: mm context of the victim | |
5373 | * @gfp_mask: reclaim mode | |
5374 | * @memcgp: charged memcg return | |
25843c2b | 5375 | * @compound: charge the page as compound or small page |
00501b53 JW |
5376 | * |
5377 | * Try to charge @page to the memcg that @mm belongs to, reclaiming | |
5378 | * pages according to @gfp_mask if necessary. | |
5379 | * | |
5380 | * Returns 0 on success, with *@memcgp pointing to the charged memcg. | |
5381 | * Otherwise, an error code is returned. | |
5382 | * | |
5383 | * After page->mapping has been set up, the caller must finalize the | |
5384 | * charge with mem_cgroup_commit_charge(). Or abort the transaction | |
5385 | * with mem_cgroup_cancel_charge() in case page instantiation fails. | |
5386 | */ | |
5387 | int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm, | |
f627c2f5 KS |
5388 | gfp_t gfp_mask, struct mem_cgroup **memcgp, |
5389 | bool compound) | |
00501b53 JW |
5390 | { |
5391 | struct mem_cgroup *memcg = NULL; | |
f627c2f5 | 5392 | unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1; |
00501b53 JW |
5393 | int ret = 0; |
5394 | ||
5395 | if (mem_cgroup_disabled()) | |
5396 | goto out; | |
5397 | ||
5398 | if (PageSwapCache(page)) { | |
00501b53 JW |
5399 | /* |
5400 | * Every swap fault against a single page tries to charge the | |
5401 | * page, bail as early as possible. shmem_unuse() encounters | |
5402 | * already charged pages, too. The USED bit is protected by | |
5403 | * the page lock, which serializes swap cache removal, which | |
5404 | * in turn serializes uncharging. | |
5405 | */ | |
e993d905 | 5406 | VM_BUG_ON_PAGE(!PageLocked(page), page); |
1306a85a | 5407 | if (page->mem_cgroup) |
00501b53 | 5408 | goto out; |
e993d905 | 5409 | |
37e84351 | 5410 | if (do_swap_account) { |
e993d905 VD |
5411 | swp_entry_t ent = { .val = page_private(page), }; |
5412 | unsigned short id = lookup_swap_cgroup_id(ent); | |
5413 | ||
5414 | rcu_read_lock(); | |
5415 | memcg = mem_cgroup_from_id(id); | |
5416 | if (memcg && !css_tryget_online(&memcg->css)) | |
5417 | memcg = NULL; | |
5418 | rcu_read_unlock(); | |
5419 | } | |
00501b53 JW |
5420 | } |
5421 | ||
00501b53 JW |
5422 | if (!memcg) |
5423 | memcg = get_mem_cgroup_from_mm(mm); | |
5424 | ||
5425 | ret = try_charge(memcg, gfp_mask, nr_pages); | |
5426 | ||
5427 | css_put(&memcg->css); | |
00501b53 JW |
5428 | out: |
5429 | *memcgp = memcg; | |
5430 | return ret; | |
5431 | } | |
5432 | ||
5433 | /** | |
5434 | * mem_cgroup_commit_charge - commit a page charge | |
5435 | * @page: page to charge | |
5436 | * @memcg: memcg to charge the page to | |
5437 | * @lrucare: page might be on LRU already | |
25843c2b | 5438 | * @compound: charge the page as compound or small page |
00501b53 JW |
5439 | * |
5440 | * Finalize a charge transaction started by mem_cgroup_try_charge(), | |
5441 | * after page->mapping has been set up. This must happen atomically | |
5442 | * as part of the page instantiation, i.e. under the page table lock | |
5443 | * for anonymous pages, under the page lock for page and swap cache. | |
5444 | * | |
5445 | * In addition, the page must not be on the LRU during the commit, to | |
5446 | * prevent racing with task migration. If it might be, use @lrucare. | |
5447 | * | |
5448 | * Use mem_cgroup_cancel_charge() to cancel the transaction instead. | |
5449 | */ | |
5450 | void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg, | |
f627c2f5 | 5451 | bool lrucare, bool compound) |
00501b53 | 5452 | { |
f627c2f5 | 5453 | unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1; |
00501b53 JW |
5454 | |
5455 | VM_BUG_ON_PAGE(!page->mapping, page); | |
5456 | VM_BUG_ON_PAGE(PageLRU(page) && !lrucare, page); | |
5457 | ||
5458 | if (mem_cgroup_disabled()) | |
5459 | return; | |
5460 | /* | |
5461 | * Swap faults will attempt to charge the same page multiple | |
5462 | * times. But reuse_swap_page() might have removed the page | |
5463 | * from swapcache already, so we can't check PageSwapCache(). | |
5464 | */ | |
5465 | if (!memcg) | |
5466 | return; | |
5467 | ||
6abb5a86 JW |
5468 | commit_charge(page, memcg, lrucare); |
5469 | ||
6abb5a86 | 5470 | local_irq_disable(); |
f627c2f5 | 5471 | mem_cgroup_charge_statistics(memcg, page, compound, nr_pages); |
6abb5a86 JW |
5472 | memcg_check_events(memcg, page); |
5473 | local_irq_enable(); | |
00501b53 | 5474 | |
7941d214 | 5475 | if (do_memsw_account() && PageSwapCache(page)) { |
00501b53 JW |
5476 | swp_entry_t entry = { .val = page_private(page) }; |
5477 | /* | |
5478 | * The swap entry might not get freed for a long time, | |
5479 | * let's not wait for it. The page already received a | |
5480 | * memory+swap charge, drop the swap entry duplicate. | |
5481 | */ | |
38d8b4e6 | 5482 | mem_cgroup_uncharge_swap(entry, nr_pages); |
00501b53 JW |
5483 | } |
5484 | } | |
5485 | ||
5486 | /** | |
5487 | * mem_cgroup_cancel_charge - cancel a page charge | |
5488 | * @page: page to charge | |
5489 | * @memcg: memcg to charge the page to | |
25843c2b | 5490 | * @compound: charge the page as compound or small page |
00501b53 JW |
5491 | * |
5492 | * Cancel a charge transaction started by mem_cgroup_try_charge(). | |
5493 | */ | |
f627c2f5 KS |
5494 | void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg, |
5495 | bool compound) | |
00501b53 | 5496 | { |
f627c2f5 | 5497 | unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1; |
00501b53 JW |
5498 | |
5499 | if (mem_cgroup_disabled()) | |
5500 | return; | |
5501 | /* | |
5502 | * Swap faults will attempt to charge the same page multiple | |
5503 | * times. But reuse_swap_page() might have removed the page | |
5504 | * from swapcache already, so we can't check PageSwapCache(). | |
5505 | */ | |
5506 | if (!memcg) | |
5507 | return; | |
5508 | ||
00501b53 JW |
5509 | cancel_charge(memcg, nr_pages); |
5510 | } | |
5511 | ||
747db954 | 5512 | static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout, |
747db954 | 5513 | unsigned long nr_anon, unsigned long nr_file, |
9a4caf1e JW |
5514 | unsigned long nr_kmem, unsigned long nr_huge, |
5515 | unsigned long nr_shmem, struct page *dummy_page) | |
747db954 | 5516 | { |
5e8d35f8 | 5517 | unsigned long nr_pages = nr_anon + nr_file + nr_kmem; |
747db954 JW |
5518 | unsigned long flags; |
5519 | ||
ce00a967 | 5520 | if (!mem_cgroup_is_root(memcg)) { |
18eca2e6 | 5521 | page_counter_uncharge(&memcg->memory, nr_pages); |
7941d214 | 5522 | if (do_memsw_account()) |
18eca2e6 | 5523 | page_counter_uncharge(&memcg->memsw, nr_pages); |
5e8d35f8 VD |
5524 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && nr_kmem) |
5525 | page_counter_uncharge(&memcg->kmem, nr_kmem); | |
ce00a967 JW |
5526 | memcg_oom_recover(memcg); |
5527 | } | |
747db954 JW |
5528 | |
5529 | local_irq_save(flags); | |
71cd3113 JW |
5530 | __this_cpu_sub(memcg->stat->count[MEMCG_RSS], nr_anon); |
5531 | __this_cpu_sub(memcg->stat->count[MEMCG_CACHE], nr_file); | |
5532 | __this_cpu_sub(memcg->stat->count[MEMCG_RSS_HUGE], nr_huge); | |
5533 | __this_cpu_sub(memcg->stat->count[NR_SHMEM], nr_shmem); | |
df0e53d0 | 5534 | __this_cpu_add(memcg->stat->events[PGPGOUT], pgpgout); |
18eca2e6 | 5535 | __this_cpu_add(memcg->stat->nr_page_events, nr_pages); |
747db954 JW |
5536 | memcg_check_events(memcg, dummy_page); |
5537 | local_irq_restore(flags); | |
e8ea14cc JW |
5538 | |
5539 | if (!mem_cgroup_is_root(memcg)) | |
18eca2e6 | 5540 | css_put_many(&memcg->css, nr_pages); |
747db954 JW |
5541 | } |
5542 | ||
5543 | static void uncharge_list(struct list_head *page_list) | |
5544 | { | |
5545 | struct mem_cgroup *memcg = NULL; | |
9a4caf1e | 5546 | unsigned long nr_shmem = 0; |
747db954 JW |
5547 | unsigned long nr_anon = 0; |
5548 | unsigned long nr_file = 0; | |
5549 | unsigned long nr_huge = 0; | |
5e8d35f8 | 5550 | unsigned long nr_kmem = 0; |
747db954 | 5551 | unsigned long pgpgout = 0; |
747db954 JW |
5552 | struct list_head *next; |
5553 | struct page *page; | |
5554 | ||
8b592656 JW |
5555 | /* |
5556 | * Note that the list can be a single page->lru; hence the | |
5557 | * do-while loop instead of a simple list_for_each_entry(). | |
5558 | */ | |
747db954 JW |
5559 | next = page_list->next; |
5560 | do { | |
747db954 JW |
5561 | page = list_entry(next, struct page, lru); |
5562 | next = page->lru.next; | |
5563 | ||
5564 | VM_BUG_ON_PAGE(PageLRU(page), page); | |
18365225 | 5565 | VM_BUG_ON_PAGE(!PageHWPoison(page) && page_count(page), page); |
747db954 | 5566 | |
1306a85a | 5567 | if (!page->mem_cgroup) |
747db954 JW |
5568 | continue; |
5569 | ||
5570 | /* | |
5571 | * Nobody should be changing or seriously looking at | |
1306a85a | 5572 | * page->mem_cgroup at this point, we have fully |
29833315 | 5573 | * exclusive access to the page. |
747db954 JW |
5574 | */ |
5575 | ||
1306a85a | 5576 | if (memcg != page->mem_cgroup) { |
747db954 | 5577 | if (memcg) { |
18eca2e6 | 5578 | uncharge_batch(memcg, pgpgout, nr_anon, nr_file, |
9a4caf1e JW |
5579 | nr_kmem, nr_huge, nr_shmem, page); |
5580 | pgpgout = nr_anon = nr_file = nr_kmem = 0; | |
5581 | nr_huge = nr_shmem = 0; | |
747db954 | 5582 | } |
1306a85a | 5583 | memcg = page->mem_cgroup; |
747db954 JW |
5584 | } |
5585 | ||
5e8d35f8 VD |
5586 | if (!PageKmemcg(page)) { |
5587 | unsigned int nr_pages = 1; | |
747db954 | 5588 | |
5e8d35f8 VD |
5589 | if (PageTransHuge(page)) { |
5590 | nr_pages <<= compound_order(page); | |
5e8d35f8 VD |
5591 | nr_huge += nr_pages; |
5592 | } | |
5593 | if (PageAnon(page)) | |
5594 | nr_anon += nr_pages; | |
9a4caf1e | 5595 | else { |
5e8d35f8 | 5596 | nr_file += nr_pages; |
9a4caf1e JW |
5597 | if (PageSwapBacked(page)) |
5598 | nr_shmem += nr_pages; | |
5599 | } | |
5e8d35f8 | 5600 | pgpgout++; |
c4159a75 | 5601 | } else { |
5e8d35f8 | 5602 | nr_kmem += 1 << compound_order(page); |
c4159a75 VD |
5603 | __ClearPageKmemcg(page); |
5604 | } | |
747db954 | 5605 | |
1306a85a | 5606 | page->mem_cgroup = NULL; |
747db954 JW |
5607 | } while (next != page_list); |
5608 | ||
5609 | if (memcg) | |
18eca2e6 | 5610 | uncharge_batch(memcg, pgpgout, nr_anon, nr_file, |
9a4caf1e | 5611 | nr_kmem, nr_huge, nr_shmem, page); |
747db954 JW |
5612 | } |
5613 | ||
0a31bc97 JW |
5614 | /** |
5615 | * mem_cgroup_uncharge - uncharge a page | |
5616 | * @page: page to uncharge | |
5617 | * | |
5618 | * Uncharge a page previously charged with mem_cgroup_try_charge() and | |
5619 | * mem_cgroup_commit_charge(). | |
5620 | */ | |
5621 | void mem_cgroup_uncharge(struct page *page) | |
5622 | { | |
0a31bc97 JW |
5623 | if (mem_cgroup_disabled()) |
5624 | return; | |
5625 | ||
747db954 | 5626 | /* Don't touch page->lru of any random page, pre-check: */ |
1306a85a | 5627 | if (!page->mem_cgroup) |
0a31bc97 JW |
5628 | return; |
5629 | ||
747db954 JW |
5630 | INIT_LIST_HEAD(&page->lru); |
5631 | uncharge_list(&page->lru); | |
5632 | } | |
0a31bc97 | 5633 | |
747db954 JW |
5634 | /** |
5635 | * mem_cgroup_uncharge_list - uncharge a list of page | |
5636 | * @page_list: list of pages to uncharge | |
5637 | * | |
5638 | * Uncharge a list of pages previously charged with | |
5639 | * mem_cgroup_try_charge() and mem_cgroup_commit_charge(). | |
5640 | */ | |
5641 | void mem_cgroup_uncharge_list(struct list_head *page_list) | |
5642 | { | |
5643 | if (mem_cgroup_disabled()) | |
5644 | return; | |
0a31bc97 | 5645 | |
747db954 JW |
5646 | if (!list_empty(page_list)) |
5647 | uncharge_list(page_list); | |
0a31bc97 JW |
5648 | } |
5649 | ||
5650 | /** | |
6a93ca8f JW |
5651 | * mem_cgroup_migrate - charge a page's replacement |
5652 | * @oldpage: currently circulating page | |
5653 | * @newpage: replacement page | |
0a31bc97 | 5654 | * |
6a93ca8f JW |
5655 | * Charge @newpage as a replacement page for @oldpage. @oldpage will |
5656 | * be uncharged upon free. | |
0a31bc97 JW |
5657 | * |
5658 | * Both pages must be locked, @newpage->mapping must be set up. | |
5659 | */ | |
6a93ca8f | 5660 | void mem_cgroup_migrate(struct page *oldpage, struct page *newpage) |
0a31bc97 | 5661 | { |
29833315 | 5662 | struct mem_cgroup *memcg; |
44b7a8d3 JW |
5663 | unsigned int nr_pages; |
5664 | bool compound; | |
d93c4130 | 5665 | unsigned long flags; |
0a31bc97 JW |
5666 | |
5667 | VM_BUG_ON_PAGE(!PageLocked(oldpage), oldpage); | |
5668 | VM_BUG_ON_PAGE(!PageLocked(newpage), newpage); | |
0a31bc97 | 5669 | VM_BUG_ON_PAGE(PageAnon(oldpage) != PageAnon(newpage), newpage); |
6abb5a86 JW |
5670 | VM_BUG_ON_PAGE(PageTransHuge(oldpage) != PageTransHuge(newpage), |
5671 | newpage); | |
0a31bc97 JW |
5672 | |
5673 | if (mem_cgroup_disabled()) | |
5674 | return; | |
5675 | ||
5676 | /* Page cache replacement: new page already charged? */ | |
1306a85a | 5677 | if (newpage->mem_cgroup) |
0a31bc97 JW |
5678 | return; |
5679 | ||
45637bab | 5680 | /* Swapcache readahead pages can get replaced before being charged */ |
1306a85a | 5681 | memcg = oldpage->mem_cgroup; |
29833315 | 5682 | if (!memcg) |
0a31bc97 JW |
5683 | return; |
5684 | ||
44b7a8d3 JW |
5685 | /* Force-charge the new page. The old one will be freed soon */ |
5686 | compound = PageTransHuge(newpage); | |
5687 | nr_pages = compound ? hpage_nr_pages(newpage) : 1; | |
5688 | ||
5689 | page_counter_charge(&memcg->memory, nr_pages); | |
5690 | if (do_memsw_account()) | |
5691 | page_counter_charge(&memcg->memsw, nr_pages); | |
5692 | css_get_many(&memcg->css, nr_pages); | |
0a31bc97 | 5693 | |
9cf7666a | 5694 | commit_charge(newpage, memcg, false); |
44b7a8d3 | 5695 | |
d93c4130 | 5696 | local_irq_save(flags); |
44b7a8d3 JW |
5697 | mem_cgroup_charge_statistics(memcg, newpage, compound, nr_pages); |
5698 | memcg_check_events(memcg, newpage); | |
d93c4130 | 5699 | local_irq_restore(flags); |
0a31bc97 JW |
5700 | } |
5701 | ||
ef12947c | 5702 | DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key); |
11092087 JW |
5703 | EXPORT_SYMBOL(memcg_sockets_enabled_key); |
5704 | ||
2d758073 | 5705 | void mem_cgroup_sk_alloc(struct sock *sk) |
11092087 JW |
5706 | { |
5707 | struct mem_cgroup *memcg; | |
5708 | ||
2d758073 JW |
5709 | if (!mem_cgroup_sockets_enabled) |
5710 | return; | |
5711 | ||
5712 | /* | |
5713 | * Socket cloning can throw us here with sk_memcg already | |
11092087 JW |
5714 | * filled. It won't however, necessarily happen from |
5715 | * process context. So the test for root memcg given | |
5716 | * the current task's memcg won't help us in this case. | |
5717 | * | |
5718 | * Respecting the original socket's memcg is a better | |
5719 | * decision in this case. | |
5720 | */ | |
5721 | if (sk->sk_memcg) { | |
5722 | BUG_ON(mem_cgroup_is_root(sk->sk_memcg)); | |
5723 | css_get(&sk->sk_memcg->css); | |
5724 | return; | |
5725 | } | |
5726 | ||
5727 | rcu_read_lock(); | |
5728 | memcg = mem_cgroup_from_task(current); | |
f7e1cb6e JW |
5729 | if (memcg == root_mem_cgroup) |
5730 | goto out; | |
0db15298 | 5731 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcpmem_active) |
f7e1cb6e | 5732 | goto out; |
f7e1cb6e | 5733 | if (css_tryget_online(&memcg->css)) |
11092087 | 5734 | sk->sk_memcg = memcg; |
f7e1cb6e | 5735 | out: |
11092087 JW |
5736 | rcu_read_unlock(); |
5737 | } | |
11092087 | 5738 | |
2d758073 | 5739 | void mem_cgroup_sk_free(struct sock *sk) |
11092087 | 5740 | { |
2d758073 JW |
5741 | if (sk->sk_memcg) |
5742 | css_put(&sk->sk_memcg->css); | |
11092087 JW |
5743 | } |
5744 | ||
5745 | /** | |
5746 | * mem_cgroup_charge_skmem - charge socket memory | |
5747 | * @memcg: memcg to charge | |
5748 | * @nr_pages: number of pages to charge | |
5749 | * | |
5750 | * Charges @nr_pages to @memcg. Returns %true if the charge fit within | |
5751 | * @memcg's configured limit, %false if the charge had to be forced. | |
5752 | */ | |
5753 | bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) | |
5754 | { | |
f7e1cb6e | 5755 | gfp_t gfp_mask = GFP_KERNEL; |
11092087 | 5756 | |
f7e1cb6e | 5757 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 5758 | struct page_counter *fail; |
f7e1cb6e | 5759 | |
0db15298 JW |
5760 | if (page_counter_try_charge(&memcg->tcpmem, nr_pages, &fail)) { |
5761 | memcg->tcpmem_pressure = 0; | |
f7e1cb6e JW |
5762 | return true; |
5763 | } | |
0db15298 JW |
5764 | page_counter_charge(&memcg->tcpmem, nr_pages); |
5765 | memcg->tcpmem_pressure = 1; | |
f7e1cb6e | 5766 | return false; |
11092087 | 5767 | } |
d886f4e4 | 5768 | |
f7e1cb6e JW |
5769 | /* Don't block in the packet receive path */ |
5770 | if (in_softirq()) | |
5771 | gfp_mask = GFP_NOWAIT; | |
5772 | ||
b2807f07 JW |
5773 | this_cpu_add(memcg->stat->count[MEMCG_SOCK], nr_pages); |
5774 | ||
f7e1cb6e JW |
5775 | if (try_charge(memcg, gfp_mask, nr_pages) == 0) |
5776 | return true; | |
5777 | ||
5778 | try_charge(memcg, gfp_mask|__GFP_NOFAIL, nr_pages); | |
11092087 JW |
5779 | return false; |
5780 | } | |
5781 | ||
5782 | /** | |
5783 | * mem_cgroup_uncharge_skmem - uncharge socket memory | |
5784 | * @memcg - memcg to uncharge | |
5785 | * @nr_pages - number of pages to uncharge | |
5786 | */ | |
5787 | void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) | |
5788 | { | |
f7e1cb6e | 5789 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 5790 | page_counter_uncharge(&memcg->tcpmem, nr_pages); |
f7e1cb6e JW |
5791 | return; |
5792 | } | |
d886f4e4 | 5793 | |
b2807f07 JW |
5794 | this_cpu_sub(memcg->stat->count[MEMCG_SOCK], nr_pages); |
5795 | ||
f7e1cb6e JW |
5796 | page_counter_uncharge(&memcg->memory, nr_pages); |
5797 | css_put_many(&memcg->css, nr_pages); | |
11092087 JW |
5798 | } |
5799 | ||
f7e1cb6e JW |
5800 | static int __init cgroup_memory(char *s) |
5801 | { | |
5802 | char *token; | |
5803 | ||
5804 | while ((token = strsep(&s, ",")) != NULL) { | |
5805 | if (!*token) | |
5806 | continue; | |
5807 | if (!strcmp(token, "nosocket")) | |
5808 | cgroup_memory_nosocket = true; | |
04823c83 VD |
5809 | if (!strcmp(token, "nokmem")) |
5810 | cgroup_memory_nokmem = true; | |
f7e1cb6e JW |
5811 | } |
5812 | return 0; | |
5813 | } | |
5814 | __setup("cgroup.memory=", cgroup_memory); | |
11092087 | 5815 | |
2d11085e | 5816 | /* |
1081312f MH |
5817 | * subsys_initcall() for memory controller. |
5818 | * | |
308167fc SAS |
5819 | * Some parts like memcg_hotplug_cpu_dead() have to be initialized from this |
5820 | * context because of lock dependencies (cgroup_lock -> cpu hotplug) but | |
5821 | * basically everything that doesn't depend on a specific mem_cgroup structure | |
5822 | * should be initialized from here. | |
2d11085e MH |
5823 | */ |
5824 | static int __init mem_cgroup_init(void) | |
5825 | { | |
95a045f6 JW |
5826 | int cpu, node; |
5827 | ||
13583c3d VD |
5828 | #ifndef CONFIG_SLOB |
5829 | /* | |
5830 | * Kmem cache creation is mostly done with the slab_mutex held, | |
17cc4dfe TH |
5831 | * so use a workqueue with limited concurrency to avoid stalling |
5832 | * all worker threads in case lots of cgroups are created and | |
5833 | * destroyed simultaneously. | |
13583c3d | 5834 | */ |
17cc4dfe TH |
5835 | memcg_kmem_cache_wq = alloc_workqueue("memcg_kmem_cache", 0, 1); |
5836 | BUG_ON(!memcg_kmem_cache_wq); | |
13583c3d VD |
5837 | #endif |
5838 | ||
308167fc SAS |
5839 | cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL, |
5840 | memcg_hotplug_cpu_dead); | |
95a045f6 JW |
5841 | |
5842 | for_each_possible_cpu(cpu) | |
5843 | INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work, | |
5844 | drain_local_stock); | |
5845 | ||
5846 | for_each_node(node) { | |
5847 | struct mem_cgroup_tree_per_node *rtpn; | |
95a045f6 JW |
5848 | |
5849 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, | |
5850 | node_online(node) ? node : NUMA_NO_NODE); | |
5851 | ||
ef8f2327 MG |
5852 | rtpn->rb_root = RB_ROOT; |
5853 | spin_lock_init(&rtpn->lock); | |
95a045f6 JW |
5854 | soft_limit_tree.rb_tree_per_node[node] = rtpn; |
5855 | } | |
5856 | ||
2d11085e MH |
5857 | return 0; |
5858 | } | |
5859 | subsys_initcall(mem_cgroup_init); | |
21afa38e JW |
5860 | |
5861 | #ifdef CONFIG_MEMCG_SWAP | |
358c07fc AB |
5862 | static struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg) |
5863 | { | |
5864 | while (!atomic_inc_not_zero(&memcg->id.ref)) { | |
5865 | /* | |
5866 | * The root cgroup cannot be destroyed, so it's refcount must | |
5867 | * always be >= 1. | |
5868 | */ | |
5869 | if (WARN_ON_ONCE(memcg == root_mem_cgroup)) { | |
5870 | VM_BUG_ON(1); | |
5871 | break; | |
5872 | } | |
5873 | memcg = parent_mem_cgroup(memcg); | |
5874 | if (!memcg) | |
5875 | memcg = root_mem_cgroup; | |
5876 | } | |
5877 | return memcg; | |
5878 | } | |
5879 | ||
21afa38e JW |
5880 | /** |
5881 | * mem_cgroup_swapout - transfer a memsw charge to swap | |
5882 | * @page: page whose memsw charge to transfer | |
5883 | * @entry: swap entry to move the charge to | |
5884 | * | |
5885 | * Transfer the memsw charge of @page to @entry. | |
5886 | */ | |
5887 | void mem_cgroup_swapout(struct page *page, swp_entry_t entry) | |
5888 | { | |
1f47b61f | 5889 | struct mem_cgroup *memcg, *swap_memcg; |
21afa38e JW |
5890 | unsigned short oldid; |
5891 | ||
5892 | VM_BUG_ON_PAGE(PageLRU(page), page); | |
5893 | VM_BUG_ON_PAGE(page_count(page), page); | |
5894 | ||
7941d214 | 5895 | if (!do_memsw_account()) |
21afa38e JW |
5896 | return; |
5897 | ||
5898 | memcg = page->mem_cgroup; | |
5899 | ||
5900 | /* Readahead page, never charged */ | |
5901 | if (!memcg) | |
5902 | return; | |
5903 | ||
1f47b61f VD |
5904 | /* |
5905 | * In case the memcg owning these pages has been offlined and doesn't | |
5906 | * have an ID allocated to it anymore, charge the closest online | |
5907 | * ancestor for the swap instead and transfer the memory+swap charge. | |
5908 | */ | |
5909 | swap_memcg = mem_cgroup_id_get_online(memcg); | |
38d8b4e6 | 5910 | oldid = swap_cgroup_record(entry, mem_cgroup_id(swap_memcg), 1); |
21afa38e | 5911 | VM_BUG_ON_PAGE(oldid, page); |
38d8b4e6 | 5912 | mem_cgroup_swap_statistics(swap_memcg, 1); |
21afa38e JW |
5913 | |
5914 | page->mem_cgroup = NULL; | |
5915 | ||
5916 | if (!mem_cgroup_is_root(memcg)) | |
5917 | page_counter_uncharge(&memcg->memory, 1); | |
5918 | ||
1f47b61f VD |
5919 | if (memcg != swap_memcg) { |
5920 | if (!mem_cgroup_is_root(swap_memcg)) | |
5921 | page_counter_charge(&swap_memcg->memsw, 1); | |
5922 | page_counter_uncharge(&memcg->memsw, 1); | |
5923 | } | |
5924 | ||
ce9ce665 SAS |
5925 | /* |
5926 | * Interrupts should be disabled here because the caller holds the | |
5927 | * mapping->tree_lock lock which is taken with interrupts-off. It is | |
5928 | * important here to have the interrupts disabled because it is the | |
5929 | * only synchronisation we have for udpating the per-CPU variables. | |
5930 | */ | |
5931 | VM_BUG_ON(!irqs_disabled()); | |
f627c2f5 | 5932 | mem_cgroup_charge_statistics(memcg, page, false, -1); |
21afa38e | 5933 | memcg_check_events(memcg, page); |
73f576c0 JW |
5934 | |
5935 | if (!mem_cgroup_is_root(memcg)) | |
5936 | css_put(&memcg->css); | |
21afa38e JW |
5937 | } |
5938 | ||
38d8b4e6 HY |
5939 | /** |
5940 | * mem_cgroup_try_charge_swap - try charging swap space for a page | |
37e84351 VD |
5941 | * @page: page being added to swap |
5942 | * @entry: swap entry to charge | |
5943 | * | |
38d8b4e6 | 5944 | * Try to charge @page's memcg for the swap space at @entry. |
37e84351 VD |
5945 | * |
5946 | * Returns 0 on success, -ENOMEM on failure. | |
5947 | */ | |
5948 | int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry) | |
5949 | { | |
38d8b4e6 | 5950 | unsigned int nr_pages = hpage_nr_pages(page); |
37e84351 | 5951 | struct page_counter *counter; |
38d8b4e6 | 5952 | struct mem_cgroup *memcg; |
37e84351 VD |
5953 | unsigned short oldid; |
5954 | ||
5955 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) || !do_swap_account) | |
5956 | return 0; | |
5957 | ||
5958 | memcg = page->mem_cgroup; | |
5959 | ||
5960 | /* Readahead page, never charged */ | |
5961 | if (!memcg) | |
5962 | return 0; | |
5963 | ||
1f47b61f VD |
5964 | memcg = mem_cgroup_id_get_online(memcg); |
5965 | ||
37e84351 | 5966 | if (!mem_cgroup_is_root(memcg) && |
38d8b4e6 | 5967 | !page_counter_try_charge(&memcg->swap, nr_pages, &counter)) { |
1f47b61f | 5968 | mem_cgroup_id_put(memcg); |
37e84351 | 5969 | return -ENOMEM; |
1f47b61f | 5970 | } |
37e84351 | 5971 | |
38d8b4e6 HY |
5972 | /* Get references for the tail pages, too */ |
5973 | if (nr_pages > 1) | |
5974 | mem_cgroup_id_get_many(memcg, nr_pages - 1); | |
5975 | oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg), nr_pages); | |
37e84351 | 5976 | VM_BUG_ON_PAGE(oldid, page); |
38d8b4e6 | 5977 | mem_cgroup_swap_statistics(memcg, nr_pages); |
37e84351 | 5978 | |
37e84351 VD |
5979 | return 0; |
5980 | } | |
5981 | ||
21afa38e | 5982 | /** |
38d8b4e6 | 5983 | * mem_cgroup_uncharge_swap - uncharge swap space |
21afa38e | 5984 | * @entry: swap entry to uncharge |
38d8b4e6 | 5985 | * @nr_pages: the amount of swap space to uncharge |
21afa38e | 5986 | */ |
38d8b4e6 | 5987 | void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages) |
21afa38e JW |
5988 | { |
5989 | struct mem_cgroup *memcg; | |
5990 | unsigned short id; | |
5991 | ||
37e84351 | 5992 | if (!do_swap_account) |
21afa38e JW |
5993 | return; |
5994 | ||
38d8b4e6 | 5995 | id = swap_cgroup_record(entry, 0, nr_pages); |
21afa38e | 5996 | rcu_read_lock(); |
adbe427b | 5997 | memcg = mem_cgroup_from_id(id); |
21afa38e | 5998 | if (memcg) { |
37e84351 VD |
5999 | if (!mem_cgroup_is_root(memcg)) { |
6000 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
38d8b4e6 | 6001 | page_counter_uncharge(&memcg->swap, nr_pages); |
37e84351 | 6002 | else |
38d8b4e6 | 6003 | page_counter_uncharge(&memcg->memsw, nr_pages); |
37e84351 | 6004 | } |
38d8b4e6 HY |
6005 | mem_cgroup_swap_statistics(memcg, -nr_pages); |
6006 | mem_cgroup_id_put_many(memcg, nr_pages); | |
21afa38e JW |
6007 | } |
6008 | rcu_read_unlock(); | |
6009 | } | |
6010 | ||
d8b38438 VD |
6011 | long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg) |
6012 | { | |
6013 | long nr_swap_pages = get_nr_swap_pages(); | |
6014 | ||
6015 | if (!do_swap_account || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
6016 | return nr_swap_pages; | |
6017 | for (; memcg != root_mem_cgroup; memcg = parent_mem_cgroup(memcg)) | |
6018 | nr_swap_pages = min_t(long, nr_swap_pages, | |
6019 | READ_ONCE(memcg->swap.limit) - | |
6020 | page_counter_read(&memcg->swap)); | |
6021 | return nr_swap_pages; | |
6022 | } | |
6023 | ||
5ccc5aba VD |
6024 | bool mem_cgroup_swap_full(struct page *page) |
6025 | { | |
6026 | struct mem_cgroup *memcg; | |
6027 | ||
6028 | VM_BUG_ON_PAGE(!PageLocked(page), page); | |
6029 | ||
6030 | if (vm_swap_full()) | |
6031 | return true; | |
6032 | if (!do_swap_account || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
6033 | return false; | |
6034 | ||
6035 | memcg = page->mem_cgroup; | |
6036 | if (!memcg) | |
6037 | return false; | |
6038 | ||
6039 | for (; memcg != root_mem_cgroup; memcg = parent_mem_cgroup(memcg)) | |
6040 | if (page_counter_read(&memcg->swap) * 2 >= memcg->swap.limit) | |
6041 | return true; | |
6042 | ||
6043 | return false; | |
6044 | } | |
6045 | ||
21afa38e JW |
6046 | /* for remember boot option*/ |
6047 | #ifdef CONFIG_MEMCG_SWAP_ENABLED | |
6048 | static int really_do_swap_account __initdata = 1; | |
6049 | #else | |
6050 | static int really_do_swap_account __initdata; | |
6051 | #endif | |
6052 | ||
6053 | static int __init enable_swap_account(char *s) | |
6054 | { | |
6055 | if (!strcmp(s, "1")) | |
6056 | really_do_swap_account = 1; | |
6057 | else if (!strcmp(s, "0")) | |
6058 | really_do_swap_account = 0; | |
6059 | return 1; | |
6060 | } | |
6061 | __setup("swapaccount=", enable_swap_account); | |
6062 | ||
37e84351 VD |
6063 | static u64 swap_current_read(struct cgroup_subsys_state *css, |
6064 | struct cftype *cft) | |
6065 | { | |
6066 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
6067 | ||
6068 | return (u64)page_counter_read(&memcg->swap) * PAGE_SIZE; | |
6069 | } | |
6070 | ||
6071 | static int swap_max_show(struct seq_file *m, void *v) | |
6072 | { | |
6073 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); | |
6074 | unsigned long max = READ_ONCE(memcg->swap.limit); | |
6075 | ||
6076 | if (max == PAGE_COUNTER_MAX) | |
6077 | seq_puts(m, "max\n"); | |
6078 | else | |
6079 | seq_printf(m, "%llu\n", (u64)max * PAGE_SIZE); | |
6080 | ||
6081 | return 0; | |
6082 | } | |
6083 | ||
6084 | static ssize_t swap_max_write(struct kernfs_open_file *of, | |
6085 | char *buf, size_t nbytes, loff_t off) | |
6086 | { | |
6087 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
6088 | unsigned long max; | |
6089 | int err; | |
6090 | ||
6091 | buf = strstrip(buf); | |
6092 | err = page_counter_memparse(buf, "max", &max); | |
6093 | if (err) | |
6094 | return err; | |
6095 | ||
6096 | mutex_lock(&memcg_limit_mutex); | |
6097 | err = page_counter_limit(&memcg->swap, max); | |
6098 | mutex_unlock(&memcg_limit_mutex); | |
6099 | if (err) | |
6100 | return err; | |
6101 | ||
6102 | return nbytes; | |
6103 | } | |
6104 | ||
6105 | static struct cftype swap_files[] = { | |
6106 | { | |
6107 | .name = "swap.current", | |
6108 | .flags = CFTYPE_NOT_ON_ROOT, | |
6109 | .read_u64 = swap_current_read, | |
6110 | }, | |
6111 | { | |
6112 | .name = "swap.max", | |
6113 | .flags = CFTYPE_NOT_ON_ROOT, | |
6114 | .seq_show = swap_max_show, | |
6115 | .write = swap_max_write, | |
6116 | }, | |
6117 | { } /* terminate */ | |
6118 | }; | |
6119 | ||
21afa38e JW |
6120 | static struct cftype memsw_cgroup_files[] = { |
6121 | { | |
6122 | .name = "memsw.usage_in_bytes", | |
6123 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
6124 | .read_u64 = mem_cgroup_read_u64, | |
6125 | }, | |
6126 | { | |
6127 | .name = "memsw.max_usage_in_bytes", | |
6128 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
6129 | .write = mem_cgroup_reset, | |
6130 | .read_u64 = mem_cgroup_read_u64, | |
6131 | }, | |
6132 | { | |
6133 | .name = "memsw.limit_in_bytes", | |
6134 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
6135 | .write = mem_cgroup_write, | |
6136 | .read_u64 = mem_cgroup_read_u64, | |
6137 | }, | |
6138 | { | |
6139 | .name = "memsw.failcnt", | |
6140 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
6141 | .write = mem_cgroup_reset, | |
6142 | .read_u64 = mem_cgroup_read_u64, | |
6143 | }, | |
6144 | { }, /* terminate */ | |
6145 | }; | |
6146 | ||
6147 | static int __init mem_cgroup_swap_init(void) | |
6148 | { | |
6149 | if (!mem_cgroup_disabled() && really_do_swap_account) { | |
6150 | do_swap_account = 1; | |
37e84351 VD |
6151 | WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, |
6152 | swap_files)); | |
21afa38e JW |
6153 | WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, |
6154 | memsw_cgroup_files)); | |
6155 | } | |
6156 | return 0; | |
6157 | } | |
6158 | subsys_initcall(mem_cgroup_swap_init); | |
6159 | ||
6160 | #endif /* CONFIG_MEMCG_SWAP */ |