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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> |
4ffef5fe | 38 | #include <linux/hugetlb.h> |
d13d1443 | 39 | #include <linux/pagemap.h> |
d52aa412 | 40 | #include <linux/smp.h> |
8a9f3ccd | 41 | #include <linux/page-flags.h> |
66e1707b | 42 | #include <linux/backing-dev.h> |
8a9f3ccd BS |
43 | #include <linux/bit_spinlock.h> |
44 | #include <linux/rcupdate.h> | |
e222432b | 45 | #include <linux/limits.h> |
b9e15baf | 46 | #include <linux/export.h> |
8c7c6e34 | 47 | #include <linux/mutex.h> |
bb4cc1a8 | 48 | #include <linux/rbtree.h> |
b6ac57d5 | 49 | #include <linux/slab.h> |
66e1707b | 50 | #include <linux/swap.h> |
02491447 | 51 | #include <linux/swapops.h> |
66e1707b | 52 | #include <linux/spinlock.h> |
2e72b634 | 53 | #include <linux/eventfd.h> |
79bd9814 | 54 | #include <linux/poll.h> |
2e72b634 | 55 | #include <linux/sort.h> |
66e1707b | 56 | #include <linux/fs.h> |
d2ceb9b7 | 57 | #include <linux/seq_file.h> |
70ddf637 | 58 | #include <linux/vmpressure.h> |
b69408e8 | 59 | #include <linux/mm_inline.h> |
5d1ea48b | 60 | #include <linux/swap_cgroup.h> |
cdec2e42 | 61 | #include <linux/cpu.h> |
158e0a2d | 62 | #include <linux/oom.h> |
0056f4e6 | 63 | #include <linux/lockdep.h> |
79bd9814 | 64 | #include <linux/file.h> |
b23afb93 | 65 | #include <linux/tracehook.h> |
08e552c6 | 66 | #include "internal.h" |
d1a4c0b3 | 67 | #include <net/sock.h> |
4bd2c1ee | 68 | #include <net/ip.h> |
f35c3a8e | 69 | #include "slab.h" |
8cdea7c0 | 70 | |
8697d331 BS |
71 | #include <asm/uaccess.h> |
72 | ||
cc8e970c KM |
73 | #include <trace/events/vmscan.h> |
74 | ||
073219e9 TH |
75 | struct cgroup_subsys memory_cgrp_subsys __read_mostly; |
76 | EXPORT_SYMBOL(memory_cgrp_subsys); | |
68ae564b | 77 | |
7d828602 JW |
78 | struct mem_cgroup *root_mem_cgroup __read_mostly; |
79 | ||
a181b0e8 | 80 | #define MEM_CGROUP_RECLAIM_RETRIES 5 |
8cdea7c0 | 81 | |
f7e1cb6e JW |
82 | /* Socket memory accounting disabled? */ |
83 | static bool cgroup_memory_nosocket; | |
84 | ||
04823c83 VD |
85 | /* Kernel memory accounting disabled? */ |
86 | static bool cgroup_memory_nokmem; | |
87 | ||
21afa38e | 88 | /* Whether the swap controller is active */ |
c255a458 | 89 | #ifdef CONFIG_MEMCG_SWAP |
c077719b | 90 | int do_swap_account __read_mostly; |
c077719b | 91 | #else |
a0db00fc | 92 | #define do_swap_account 0 |
c077719b KH |
93 | #endif |
94 | ||
7941d214 JW |
95 | /* Whether legacy memory+swap accounting is active */ |
96 | static bool do_memsw_account(void) | |
97 | { | |
98 | return !cgroup_subsys_on_dfl(memory_cgrp_subsys) && do_swap_account; | |
99 | } | |
100 | ||
af7c4b0e JW |
101 | static const char * const mem_cgroup_stat_names[] = { |
102 | "cache", | |
103 | "rss", | |
b070e65c | 104 | "rss_huge", |
af7c4b0e | 105 | "mapped_file", |
c4843a75 | 106 | "dirty", |
3ea67d06 | 107 | "writeback", |
af7c4b0e JW |
108 | "swap", |
109 | }; | |
110 | ||
af7c4b0e JW |
111 | static const char * const mem_cgroup_events_names[] = { |
112 | "pgpgin", | |
113 | "pgpgout", | |
114 | "pgfault", | |
115 | "pgmajfault", | |
116 | }; | |
117 | ||
58cf188e SZ |
118 | static const char * const mem_cgroup_lru_names[] = { |
119 | "inactive_anon", | |
120 | "active_anon", | |
121 | "inactive_file", | |
122 | "active_file", | |
123 | "unevictable", | |
124 | }; | |
125 | ||
a0db00fc KS |
126 | #define THRESHOLDS_EVENTS_TARGET 128 |
127 | #define SOFTLIMIT_EVENTS_TARGET 1024 | |
128 | #define NUMAINFO_EVENTS_TARGET 1024 | |
e9f8974f | 129 | |
bb4cc1a8 AM |
130 | /* |
131 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
132 | * their hierarchy representation | |
133 | */ | |
134 | ||
135 | struct mem_cgroup_tree_per_zone { | |
136 | struct rb_root rb_root; | |
137 | spinlock_t lock; | |
138 | }; | |
139 | ||
140 | struct mem_cgroup_tree_per_node { | |
141 | struct mem_cgroup_tree_per_zone rb_tree_per_zone[MAX_NR_ZONES]; | |
142 | }; | |
143 | ||
144 | struct mem_cgroup_tree { | |
145 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
146 | }; | |
147 | ||
148 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
149 | ||
9490ff27 KH |
150 | /* for OOM */ |
151 | struct mem_cgroup_eventfd_list { | |
152 | struct list_head list; | |
153 | struct eventfd_ctx *eventfd; | |
154 | }; | |
2e72b634 | 155 | |
79bd9814 TH |
156 | /* |
157 | * cgroup_event represents events which userspace want to receive. | |
158 | */ | |
3bc942f3 | 159 | struct mem_cgroup_event { |
79bd9814 | 160 | /* |
59b6f873 | 161 | * memcg which the event belongs to. |
79bd9814 | 162 | */ |
59b6f873 | 163 | struct mem_cgroup *memcg; |
79bd9814 TH |
164 | /* |
165 | * eventfd to signal userspace about the event. | |
166 | */ | |
167 | struct eventfd_ctx *eventfd; | |
168 | /* | |
169 | * Each of these stored in a list by the cgroup. | |
170 | */ | |
171 | struct list_head list; | |
fba94807 TH |
172 | /* |
173 | * register_event() callback will be used to add new userspace | |
174 | * waiter for changes related to this event. Use eventfd_signal() | |
175 | * on eventfd to send notification to userspace. | |
176 | */ | |
59b6f873 | 177 | int (*register_event)(struct mem_cgroup *memcg, |
347c4a87 | 178 | struct eventfd_ctx *eventfd, const char *args); |
fba94807 TH |
179 | /* |
180 | * unregister_event() callback will be called when userspace closes | |
181 | * the eventfd or on cgroup removing. This callback must be set, | |
182 | * if you want provide notification functionality. | |
183 | */ | |
59b6f873 | 184 | void (*unregister_event)(struct mem_cgroup *memcg, |
fba94807 | 185 | struct eventfd_ctx *eventfd); |
79bd9814 TH |
186 | /* |
187 | * All fields below needed to unregister event when | |
188 | * userspace closes eventfd. | |
189 | */ | |
190 | poll_table pt; | |
191 | wait_queue_head_t *wqh; | |
192 | wait_queue_t wait; | |
193 | struct work_struct remove; | |
194 | }; | |
195 | ||
c0ff4b85 R |
196 | static void mem_cgroup_threshold(struct mem_cgroup *memcg); |
197 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); | |
2e72b634 | 198 | |
7dc74be0 DN |
199 | /* Stuffs for move charges at task migration. */ |
200 | /* | |
1dfab5ab | 201 | * Types of charges to be moved. |
7dc74be0 | 202 | */ |
1dfab5ab JW |
203 | #define MOVE_ANON 0x1U |
204 | #define MOVE_FILE 0x2U | |
205 | #define MOVE_MASK (MOVE_ANON | MOVE_FILE) | |
7dc74be0 | 206 | |
4ffef5fe DN |
207 | /* "mc" and its members are protected by cgroup_mutex */ |
208 | static struct move_charge_struct { | |
b1dd693e | 209 | spinlock_t lock; /* for from, to */ |
4ffef5fe DN |
210 | struct mem_cgroup *from; |
211 | struct mem_cgroup *to; | |
1dfab5ab | 212 | unsigned long flags; |
4ffef5fe | 213 | unsigned long precharge; |
854ffa8d | 214 | unsigned long moved_charge; |
483c30b5 | 215 | unsigned long moved_swap; |
8033b97c DN |
216 | struct task_struct *moving_task; /* a task moving charges */ |
217 | wait_queue_head_t waitq; /* a waitq for other context */ | |
218 | } mc = { | |
2bd9bb20 | 219 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
220 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
221 | }; | |
4ffef5fe | 222 | |
4e416953 BS |
223 | /* |
224 | * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft | |
225 | * limit reclaim to prevent infinite loops, if they ever occur. | |
226 | */ | |
a0db00fc | 227 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS 100 |
bb4cc1a8 | 228 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS 2 |
4e416953 | 229 | |
217bc319 KH |
230 | enum charge_type { |
231 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, | |
41326c17 | 232 | MEM_CGROUP_CHARGE_TYPE_ANON, |
d13d1443 | 233 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
8a9478ca | 234 | MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ |
c05555b5 KH |
235 | NR_CHARGE_TYPE, |
236 | }; | |
237 | ||
8c7c6e34 | 238 | /* for encoding cft->private value on file */ |
86ae53e1 GC |
239 | enum res_type { |
240 | _MEM, | |
241 | _MEMSWAP, | |
242 | _OOM_TYPE, | |
510fc4e1 | 243 | _KMEM, |
d55f90bf | 244 | _TCP, |
86ae53e1 GC |
245 | }; |
246 | ||
a0db00fc KS |
247 | #define MEMFILE_PRIVATE(x, val) ((x) << 16 | (val)) |
248 | #define MEMFILE_TYPE(val) ((val) >> 16 & 0xffff) | |
8c7c6e34 | 249 | #define MEMFILE_ATTR(val) ((val) & 0xffff) |
9490ff27 KH |
250 | /* Used for OOM nofiier */ |
251 | #define OOM_CONTROL (0) | |
8c7c6e34 | 252 | |
70ddf637 AV |
253 | /* Some nice accessors for the vmpressure. */ |
254 | struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg) | |
255 | { | |
256 | if (!memcg) | |
257 | memcg = root_mem_cgroup; | |
258 | return &memcg->vmpressure; | |
259 | } | |
260 | ||
261 | struct cgroup_subsys_state *vmpressure_to_css(struct vmpressure *vmpr) | |
262 | { | |
263 | return &container_of(vmpr, struct mem_cgroup, vmpressure)->css; | |
264 | } | |
265 | ||
7ffc0edc MH |
266 | static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) |
267 | { | |
268 | return (memcg == root_mem_cgroup); | |
269 | } | |
270 | ||
4219b2da LZ |
271 | /* |
272 | * We restrict the id in the range of [1, 65535], so it can fit into | |
273 | * an unsigned short. | |
274 | */ | |
275 | #define MEM_CGROUP_ID_MAX USHRT_MAX | |
276 | ||
34c00c31 LZ |
277 | static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg) |
278 | { | |
15a4c835 | 279 | return memcg->css.id; |
34c00c31 LZ |
280 | } |
281 | ||
adbe427b VD |
282 | /* |
283 | * A helper function to get mem_cgroup from ID. must be called under | |
284 | * rcu_read_lock(). The caller is responsible for calling | |
285 | * css_tryget_online() if the mem_cgroup is used for charging. (dropping | |
286 | * refcnt from swap can be called against removed memcg.) | |
287 | */ | |
34c00c31 LZ |
288 | static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id) |
289 | { | |
290 | struct cgroup_subsys_state *css; | |
291 | ||
7d699ddb | 292 | css = css_from_id(id, &memory_cgrp_subsys); |
34c00c31 LZ |
293 | return mem_cgroup_from_css(css); |
294 | } | |
295 | ||
127424c8 | 296 | #ifndef CONFIG_SLOB |
55007d84 | 297 | /* |
f7ce3190 | 298 | * This will be the memcg's index in each cache's ->memcg_params.memcg_caches. |
b8627835 LZ |
299 | * The main reason for not using cgroup id for this: |
300 | * this works better in sparse environments, where we have a lot of memcgs, | |
301 | * but only a few kmem-limited. Or also, if we have, for instance, 200 | |
302 | * memcgs, and none but the 200th is kmem-limited, we'd have to have a | |
303 | * 200 entry array for that. | |
55007d84 | 304 | * |
dbcf73e2 VD |
305 | * The current size of the caches array is stored in memcg_nr_cache_ids. It |
306 | * will double each time we have to increase it. | |
55007d84 | 307 | */ |
dbcf73e2 VD |
308 | static DEFINE_IDA(memcg_cache_ida); |
309 | int memcg_nr_cache_ids; | |
749c5415 | 310 | |
05257a1a VD |
311 | /* Protects memcg_nr_cache_ids */ |
312 | static DECLARE_RWSEM(memcg_cache_ids_sem); | |
313 | ||
314 | void memcg_get_cache_ids(void) | |
315 | { | |
316 | down_read(&memcg_cache_ids_sem); | |
317 | } | |
318 | ||
319 | void memcg_put_cache_ids(void) | |
320 | { | |
321 | up_read(&memcg_cache_ids_sem); | |
322 | } | |
323 | ||
55007d84 GC |
324 | /* |
325 | * MIN_SIZE is different than 1, because we would like to avoid going through | |
326 | * the alloc/free process all the time. In a small machine, 4 kmem-limited | |
327 | * cgroups is a reasonable guess. In the future, it could be a parameter or | |
328 | * tunable, but that is strictly not necessary. | |
329 | * | |
b8627835 | 330 | * MAX_SIZE should be as large as the number of cgrp_ids. Ideally, we could get |
55007d84 GC |
331 | * this constant directly from cgroup, but it is understandable that this is |
332 | * better kept as an internal representation in cgroup.c. In any case, the | |
b8627835 | 333 | * cgrp_id space is not getting any smaller, and we don't have to necessarily |
55007d84 GC |
334 | * increase ours as well if it increases. |
335 | */ | |
336 | #define MEMCG_CACHES_MIN_SIZE 4 | |
b8627835 | 337 | #define MEMCG_CACHES_MAX_SIZE MEM_CGROUP_ID_MAX |
55007d84 | 338 | |
d7f25f8a GC |
339 | /* |
340 | * A lot of the calls to the cache allocation functions are expected to be | |
341 | * inlined by the compiler. Since the calls to memcg_kmem_get_cache are | |
342 | * conditional to this static branch, we'll have to allow modules that does | |
343 | * kmem_cache_alloc and the such to see this symbol as well | |
344 | */ | |
ef12947c | 345 | DEFINE_STATIC_KEY_FALSE(memcg_kmem_enabled_key); |
d7f25f8a | 346 | EXPORT_SYMBOL(memcg_kmem_enabled_key); |
a8964b9b | 347 | |
127424c8 | 348 | #endif /* !CONFIG_SLOB */ |
a8964b9b | 349 | |
f64c3f54 | 350 | static struct mem_cgroup_per_zone * |
e231875b | 351 | mem_cgroup_zone_zoneinfo(struct mem_cgroup *memcg, struct zone *zone) |
f64c3f54 | 352 | { |
e231875b JZ |
353 | int nid = zone_to_nid(zone); |
354 | int zid = zone_idx(zone); | |
355 | ||
54f72fe0 | 356 | return &memcg->nodeinfo[nid]->zoneinfo[zid]; |
f64c3f54 BS |
357 | } |
358 | ||
ad7fa852 TH |
359 | /** |
360 | * mem_cgroup_css_from_page - css of the memcg associated with a page | |
361 | * @page: page of interest | |
362 | * | |
363 | * If memcg is bound to the default hierarchy, css of the memcg associated | |
364 | * with @page is returned. The returned css remains associated with @page | |
365 | * until it is released. | |
366 | * | |
367 | * If memcg is bound to a traditional hierarchy, the css of root_mem_cgroup | |
368 | * is returned. | |
369 | * | |
370 | * XXX: The above description of behavior on the default hierarchy isn't | |
371 | * strictly true yet as replace_page_cache_page() can modify the | |
372 | * association before @page is released even on the default hierarchy; | |
373 | * however, the current and planned usages don't mix the the two functions | |
374 | * and replace_page_cache_page() will soon be updated to make the invariant | |
375 | * actually true. | |
376 | */ | |
377 | struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page) | |
378 | { | |
379 | struct mem_cgroup *memcg; | |
380 | ||
ad7fa852 TH |
381 | memcg = page->mem_cgroup; |
382 | ||
9e10a130 | 383 | if (!memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
ad7fa852 TH |
384 | memcg = root_mem_cgroup; |
385 | ||
ad7fa852 TH |
386 | return &memcg->css; |
387 | } | |
388 | ||
2fc04524 VD |
389 | /** |
390 | * page_cgroup_ino - return inode number of the memcg a page is charged to | |
391 | * @page: the page | |
392 | * | |
393 | * Look up the closest online ancestor of the memory cgroup @page is charged to | |
394 | * and return its inode number or 0 if @page is not charged to any cgroup. It | |
395 | * is safe to call this function without holding a reference to @page. | |
396 | * | |
397 | * Note, this function is inherently racy, because there is nothing to prevent | |
398 | * the cgroup inode from getting torn down and potentially reallocated a moment | |
399 | * after page_cgroup_ino() returns, so it only should be used by callers that | |
400 | * do not care (such as procfs interfaces). | |
401 | */ | |
402 | ino_t page_cgroup_ino(struct page *page) | |
403 | { | |
404 | struct mem_cgroup *memcg; | |
405 | unsigned long ino = 0; | |
406 | ||
407 | rcu_read_lock(); | |
408 | memcg = READ_ONCE(page->mem_cgroup); | |
409 | while (memcg && !(memcg->css.flags & CSS_ONLINE)) | |
410 | memcg = parent_mem_cgroup(memcg); | |
411 | if (memcg) | |
412 | ino = cgroup_ino(memcg->css.cgroup); | |
413 | rcu_read_unlock(); | |
414 | return ino; | |
415 | } | |
416 | ||
f64c3f54 | 417 | static struct mem_cgroup_per_zone * |
e231875b | 418 | mem_cgroup_page_zoneinfo(struct mem_cgroup *memcg, struct page *page) |
f64c3f54 | 419 | { |
97a6c37b JW |
420 | int nid = page_to_nid(page); |
421 | int zid = page_zonenum(page); | |
f64c3f54 | 422 | |
e231875b | 423 | return &memcg->nodeinfo[nid]->zoneinfo[zid]; |
f64c3f54 BS |
424 | } |
425 | ||
bb4cc1a8 AM |
426 | static struct mem_cgroup_tree_per_zone * |
427 | soft_limit_tree_node_zone(int nid, int zid) | |
428 | { | |
429 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
430 | } | |
431 | ||
432 | static struct mem_cgroup_tree_per_zone * | |
433 | soft_limit_tree_from_page(struct page *page) | |
434 | { | |
435 | int nid = page_to_nid(page); | |
436 | int zid = page_zonenum(page); | |
437 | ||
438 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
439 | } | |
440 | ||
cf2c8127 JW |
441 | static void __mem_cgroup_insert_exceeded(struct mem_cgroup_per_zone *mz, |
442 | struct mem_cgroup_tree_per_zone *mctz, | |
3e32cb2e | 443 | unsigned long new_usage_in_excess) |
bb4cc1a8 AM |
444 | { |
445 | struct rb_node **p = &mctz->rb_root.rb_node; | |
446 | struct rb_node *parent = NULL; | |
447 | struct mem_cgroup_per_zone *mz_node; | |
448 | ||
449 | if (mz->on_tree) | |
450 | return; | |
451 | ||
452 | mz->usage_in_excess = new_usage_in_excess; | |
453 | if (!mz->usage_in_excess) | |
454 | return; | |
455 | while (*p) { | |
456 | parent = *p; | |
457 | mz_node = rb_entry(parent, struct mem_cgroup_per_zone, | |
458 | tree_node); | |
459 | if (mz->usage_in_excess < mz_node->usage_in_excess) | |
460 | p = &(*p)->rb_left; | |
461 | /* | |
462 | * We can't avoid mem cgroups that are over their soft | |
463 | * limit by the same amount | |
464 | */ | |
465 | else if (mz->usage_in_excess >= mz_node->usage_in_excess) | |
466 | p = &(*p)->rb_right; | |
467 | } | |
468 | rb_link_node(&mz->tree_node, parent, p); | |
469 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
470 | mz->on_tree = true; | |
471 | } | |
472 | ||
cf2c8127 JW |
473 | static void __mem_cgroup_remove_exceeded(struct mem_cgroup_per_zone *mz, |
474 | struct mem_cgroup_tree_per_zone *mctz) | |
bb4cc1a8 AM |
475 | { |
476 | if (!mz->on_tree) | |
477 | return; | |
478 | rb_erase(&mz->tree_node, &mctz->rb_root); | |
479 | mz->on_tree = false; | |
480 | } | |
481 | ||
cf2c8127 JW |
482 | static void mem_cgroup_remove_exceeded(struct mem_cgroup_per_zone *mz, |
483 | struct mem_cgroup_tree_per_zone *mctz) | |
bb4cc1a8 | 484 | { |
0a31bc97 JW |
485 | unsigned long flags; |
486 | ||
487 | spin_lock_irqsave(&mctz->lock, flags); | |
cf2c8127 | 488 | __mem_cgroup_remove_exceeded(mz, mctz); |
0a31bc97 | 489 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
490 | } |
491 | ||
3e32cb2e JW |
492 | static unsigned long soft_limit_excess(struct mem_cgroup *memcg) |
493 | { | |
494 | unsigned long nr_pages = page_counter_read(&memcg->memory); | |
4db0c3c2 | 495 | unsigned long soft_limit = READ_ONCE(memcg->soft_limit); |
3e32cb2e JW |
496 | unsigned long excess = 0; |
497 | ||
498 | if (nr_pages > soft_limit) | |
499 | excess = nr_pages - soft_limit; | |
500 | ||
501 | return excess; | |
502 | } | |
bb4cc1a8 AM |
503 | |
504 | static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page) | |
505 | { | |
3e32cb2e | 506 | unsigned long excess; |
bb4cc1a8 AM |
507 | struct mem_cgroup_per_zone *mz; |
508 | struct mem_cgroup_tree_per_zone *mctz; | |
bb4cc1a8 | 509 | |
e231875b | 510 | mctz = soft_limit_tree_from_page(page); |
bb4cc1a8 AM |
511 | /* |
512 | * Necessary to update all ancestors when hierarchy is used. | |
513 | * because their event counter is not touched. | |
514 | */ | |
515 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { | |
e231875b | 516 | mz = mem_cgroup_page_zoneinfo(memcg, page); |
3e32cb2e | 517 | excess = soft_limit_excess(memcg); |
bb4cc1a8 AM |
518 | /* |
519 | * We have to update the tree if mz is on RB-tree or | |
520 | * mem is over its softlimit. | |
521 | */ | |
522 | if (excess || mz->on_tree) { | |
0a31bc97 JW |
523 | unsigned long flags; |
524 | ||
525 | spin_lock_irqsave(&mctz->lock, flags); | |
bb4cc1a8 AM |
526 | /* if on-tree, remove it */ |
527 | if (mz->on_tree) | |
cf2c8127 | 528 | __mem_cgroup_remove_exceeded(mz, mctz); |
bb4cc1a8 AM |
529 | /* |
530 | * Insert again. mz->usage_in_excess will be updated. | |
531 | * If excess is 0, no tree ops. | |
532 | */ | |
cf2c8127 | 533 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 534 | spin_unlock_irqrestore(&mctz->lock, flags); |
bb4cc1a8 AM |
535 | } |
536 | } | |
537 | } | |
538 | ||
539 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) | |
540 | { | |
bb4cc1a8 | 541 | struct mem_cgroup_tree_per_zone *mctz; |
e231875b JZ |
542 | struct mem_cgroup_per_zone *mz; |
543 | int nid, zid; | |
bb4cc1a8 | 544 | |
e231875b JZ |
545 | for_each_node(nid) { |
546 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
547 | mz = &memcg->nodeinfo[nid]->zoneinfo[zid]; | |
548 | mctz = soft_limit_tree_node_zone(nid, zid); | |
cf2c8127 | 549 | mem_cgroup_remove_exceeded(mz, mctz); |
bb4cc1a8 AM |
550 | } |
551 | } | |
552 | } | |
553 | ||
554 | static struct mem_cgroup_per_zone * | |
555 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
556 | { | |
557 | struct rb_node *rightmost = NULL; | |
558 | struct mem_cgroup_per_zone *mz; | |
559 | ||
560 | retry: | |
561 | mz = NULL; | |
562 | rightmost = rb_last(&mctz->rb_root); | |
563 | if (!rightmost) | |
564 | goto done; /* Nothing to reclaim from */ | |
565 | ||
566 | mz = rb_entry(rightmost, struct mem_cgroup_per_zone, tree_node); | |
567 | /* | |
568 | * Remove the node now but someone else can add it back, | |
569 | * we will to add it back at the end of reclaim to its correct | |
570 | * position in the tree. | |
571 | */ | |
cf2c8127 | 572 | __mem_cgroup_remove_exceeded(mz, mctz); |
3e32cb2e | 573 | if (!soft_limit_excess(mz->memcg) || |
ec903c0c | 574 | !css_tryget_online(&mz->memcg->css)) |
bb4cc1a8 AM |
575 | goto retry; |
576 | done: | |
577 | return mz; | |
578 | } | |
579 | ||
580 | static struct mem_cgroup_per_zone * | |
581 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
582 | { | |
583 | struct mem_cgroup_per_zone *mz; | |
584 | ||
0a31bc97 | 585 | spin_lock_irq(&mctz->lock); |
bb4cc1a8 | 586 | mz = __mem_cgroup_largest_soft_limit_node(mctz); |
0a31bc97 | 587 | spin_unlock_irq(&mctz->lock); |
bb4cc1a8 AM |
588 | return mz; |
589 | } | |
590 | ||
711d3d2c | 591 | /* |
484ebb3b GT |
592 | * Return page count for single (non recursive) @memcg. |
593 | * | |
711d3d2c KH |
594 | * Implementation Note: reading percpu statistics for memcg. |
595 | * | |
596 | * Both of vmstat[] and percpu_counter has threshold and do periodic | |
597 | * synchronization to implement "quick" read. There are trade-off between | |
598 | * reading cost and precision of value. Then, we may have a chance to implement | |
484ebb3b | 599 | * a periodic synchronization of counter in memcg's counter. |
711d3d2c KH |
600 | * |
601 | * But this _read() function is used for user interface now. The user accounts | |
602 | * memory usage by memory cgroup and he _always_ requires exact value because | |
603 | * he accounts memory. Even if we provide quick-and-fuzzy read, we always | |
604 | * have to visit all online cpus and make sum. So, for now, unnecessary | |
605 | * synchronization is not implemented. (just implemented for cpu hotplug) | |
606 | * | |
607 | * If there are kernel internal actions which can make use of some not-exact | |
608 | * value, and reading all cpu value can be performance bottleneck in some | |
484ebb3b | 609 | * common workload, threshold and synchronization as vmstat[] should be |
711d3d2c KH |
610 | * implemented. |
611 | */ | |
484ebb3b GT |
612 | static unsigned long |
613 | mem_cgroup_read_stat(struct mem_cgroup *memcg, enum mem_cgroup_stat_index idx) | |
c62b1a3b | 614 | { |
7a159cc9 | 615 | long val = 0; |
c62b1a3b | 616 | int cpu; |
c62b1a3b | 617 | |
484ebb3b | 618 | /* Per-cpu values can be negative, use a signed accumulator */ |
733a572e | 619 | for_each_possible_cpu(cpu) |
c0ff4b85 | 620 | val += per_cpu(memcg->stat->count[idx], cpu); |
484ebb3b GT |
621 | /* |
622 | * Summing races with updates, so val may be negative. Avoid exposing | |
623 | * transient negative values. | |
624 | */ | |
625 | if (val < 0) | |
626 | val = 0; | |
c62b1a3b KH |
627 | return val; |
628 | } | |
629 | ||
c0ff4b85 | 630 | static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg, |
e9f8974f JW |
631 | enum mem_cgroup_events_index idx) |
632 | { | |
633 | unsigned long val = 0; | |
634 | int cpu; | |
635 | ||
733a572e | 636 | for_each_possible_cpu(cpu) |
c0ff4b85 | 637 | val += per_cpu(memcg->stat->events[idx], cpu); |
e9f8974f JW |
638 | return val; |
639 | } | |
640 | ||
c0ff4b85 | 641 | static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, |
b070e65c | 642 | struct page *page, |
f627c2f5 | 643 | bool compound, int nr_pages) |
d52aa412 | 644 | { |
b2402857 KH |
645 | /* |
646 | * Here, RSS means 'mapped anon' and anon's SwapCache. Shmem/tmpfs is | |
647 | * counted as CACHE even if it's on ANON LRU. | |
648 | */ | |
0a31bc97 | 649 | if (PageAnon(page)) |
b2402857 | 650 | __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_RSS], |
c0ff4b85 | 651 | nr_pages); |
d52aa412 | 652 | else |
b2402857 | 653 | __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_CACHE], |
c0ff4b85 | 654 | nr_pages); |
55e462b0 | 655 | |
f627c2f5 KS |
656 | if (compound) { |
657 | VM_BUG_ON_PAGE(!PageTransHuge(page), page); | |
b070e65c DR |
658 | __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], |
659 | nr_pages); | |
f627c2f5 | 660 | } |
b070e65c | 661 | |
e401f176 KH |
662 | /* pagein of a big page is an event. So, ignore page size */ |
663 | if (nr_pages > 0) | |
c0ff4b85 | 664 | __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGIN]); |
3751d604 | 665 | else { |
c0ff4b85 | 666 | __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT]); |
3751d604 KH |
667 | nr_pages = -nr_pages; /* for event */ |
668 | } | |
e401f176 | 669 | |
13114716 | 670 | __this_cpu_add(memcg->stat->nr_page_events, nr_pages); |
6d12e2d8 KH |
671 | } |
672 | ||
e231875b JZ |
673 | static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, |
674 | int nid, | |
675 | unsigned int lru_mask) | |
bb2a0de9 | 676 | { |
e231875b | 677 | unsigned long nr = 0; |
889976db YH |
678 | int zid; |
679 | ||
e231875b | 680 | VM_BUG_ON((unsigned)nid >= nr_node_ids); |
bb2a0de9 | 681 | |
e231875b JZ |
682 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { |
683 | struct mem_cgroup_per_zone *mz; | |
684 | enum lru_list lru; | |
685 | ||
686 | for_each_lru(lru) { | |
687 | if (!(BIT(lru) & lru_mask)) | |
688 | continue; | |
689 | mz = &memcg->nodeinfo[nid]->zoneinfo[zid]; | |
690 | nr += mz->lru_size[lru]; | |
691 | } | |
692 | } | |
693 | return nr; | |
889976db | 694 | } |
bb2a0de9 | 695 | |
c0ff4b85 | 696 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, |
bb2a0de9 | 697 | unsigned int lru_mask) |
6d12e2d8 | 698 | { |
e231875b | 699 | unsigned long nr = 0; |
889976db | 700 | int nid; |
6d12e2d8 | 701 | |
31aaea4a | 702 | for_each_node_state(nid, N_MEMORY) |
e231875b JZ |
703 | nr += mem_cgroup_node_nr_lru_pages(memcg, nid, lru_mask); |
704 | return nr; | |
d52aa412 KH |
705 | } |
706 | ||
f53d7ce3 JW |
707 | static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg, |
708 | enum mem_cgroup_events_target target) | |
7a159cc9 JW |
709 | { |
710 | unsigned long val, next; | |
711 | ||
13114716 | 712 | val = __this_cpu_read(memcg->stat->nr_page_events); |
4799401f | 713 | next = __this_cpu_read(memcg->stat->targets[target]); |
7a159cc9 | 714 | /* from time_after() in jiffies.h */ |
f53d7ce3 JW |
715 | if ((long)next - (long)val < 0) { |
716 | switch (target) { | |
717 | case MEM_CGROUP_TARGET_THRESH: | |
718 | next = val + THRESHOLDS_EVENTS_TARGET; | |
719 | break; | |
bb4cc1a8 AM |
720 | case MEM_CGROUP_TARGET_SOFTLIMIT: |
721 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
722 | break; | |
f53d7ce3 JW |
723 | case MEM_CGROUP_TARGET_NUMAINFO: |
724 | next = val + NUMAINFO_EVENTS_TARGET; | |
725 | break; | |
726 | default: | |
727 | break; | |
728 | } | |
729 | __this_cpu_write(memcg->stat->targets[target], next); | |
730 | return true; | |
7a159cc9 | 731 | } |
f53d7ce3 | 732 | return false; |
d2265e6f KH |
733 | } |
734 | ||
735 | /* | |
736 | * Check events in order. | |
737 | * | |
738 | */ | |
c0ff4b85 | 739 | static void memcg_check_events(struct mem_cgroup *memcg, struct page *page) |
d2265e6f KH |
740 | { |
741 | /* threshold event is triggered in finer grain than soft limit */ | |
f53d7ce3 JW |
742 | if (unlikely(mem_cgroup_event_ratelimit(memcg, |
743 | MEM_CGROUP_TARGET_THRESH))) { | |
bb4cc1a8 | 744 | bool do_softlimit; |
82b3f2a7 | 745 | bool do_numainfo __maybe_unused; |
f53d7ce3 | 746 | |
bb4cc1a8 AM |
747 | do_softlimit = mem_cgroup_event_ratelimit(memcg, |
748 | MEM_CGROUP_TARGET_SOFTLIMIT); | |
f53d7ce3 JW |
749 | #if MAX_NUMNODES > 1 |
750 | do_numainfo = mem_cgroup_event_ratelimit(memcg, | |
751 | MEM_CGROUP_TARGET_NUMAINFO); | |
752 | #endif | |
c0ff4b85 | 753 | mem_cgroup_threshold(memcg); |
bb4cc1a8 AM |
754 | if (unlikely(do_softlimit)) |
755 | mem_cgroup_update_tree(memcg, page); | |
453a9bf3 | 756 | #if MAX_NUMNODES > 1 |
f53d7ce3 | 757 | if (unlikely(do_numainfo)) |
c0ff4b85 | 758 | atomic_inc(&memcg->numainfo_events); |
453a9bf3 | 759 | #endif |
0a31bc97 | 760 | } |
d2265e6f KH |
761 | } |
762 | ||
cf475ad2 | 763 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 764 | { |
31a78f23 BS |
765 | /* |
766 | * mm_update_next_owner() may clear mm->owner to NULL | |
767 | * if it races with swapoff, page migration, etc. | |
768 | * So this can be called with p == NULL. | |
769 | */ | |
770 | if (unlikely(!p)) | |
771 | return NULL; | |
772 | ||
073219e9 | 773 | return mem_cgroup_from_css(task_css(p, memory_cgrp_id)); |
78fb7466 | 774 | } |
33398cf2 | 775 | EXPORT_SYMBOL(mem_cgroup_from_task); |
78fb7466 | 776 | |
df381975 | 777 | static struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm) |
54595fe2 | 778 | { |
c0ff4b85 | 779 | struct mem_cgroup *memcg = NULL; |
0b7f569e | 780 | |
54595fe2 KH |
781 | rcu_read_lock(); |
782 | do { | |
6f6acb00 MH |
783 | /* |
784 | * Page cache insertions can happen withou an | |
785 | * actual mm context, e.g. during disk probing | |
786 | * on boot, loopback IO, acct() writes etc. | |
787 | */ | |
788 | if (unlikely(!mm)) | |
df381975 | 789 | memcg = root_mem_cgroup; |
6f6acb00 MH |
790 | else { |
791 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
792 | if (unlikely(!memcg)) | |
793 | memcg = root_mem_cgroup; | |
794 | } | |
ec903c0c | 795 | } while (!css_tryget_online(&memcg->css)); |
54595fe2 | 796 | rcu_read_unlock(); |
c0ff4b85 | 797 | return memcg; |
54595fe2 KH |
798 | } |
799 | ||
5660048c JW |
800 | /** |
801 | * mem_cgroup_iter - iterate over memory cgroup hierarchy | |
802 | * @root: hierarchy root | |
803 | * @prev: previously returned memcg, NULL on first invocation | |
804 | * @reclaim: cookie for shared reclaim walks, NULL for full walks | |
805 | * | |
806 | * Returns references to children of the hierarchy below @root, or | |
807 | * @root itself, or %NULL after a full round-trip. | |
808 | * | |
809 | * Caller must pass the return value in @prev on subsequent | |
810 | * invocations for reference counting, or use mem_cgroup_iter_break() | |
811 | * to cancel a hierarchy walk before the round-trip is complete. | |
812 | * | |
813 | * Reclaimers can specify a zone and a priority level in @reclaim to | |
814 | * divide up the memcgs in the hierarchy among all concurrent | |
815 | * reclaimers operating on the same zone and priority. | |
816 | */ | |
694fbc0f | 817 | struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, |
5660048c | 818 | struct mem_cgroup *prev, |
694fbc0f | 819 | struct mem_cgroup_reclaim_cookie *reclaim) |
14067bb3 | 820 | { |
33398cf2 | 821 | struct mem_cgroup_reclaim_iter *uninitialized_var(iter); |
5ac8fb31 | 822 | struct cgroup_subsys_state *css = NULL; |
9f3a0d09 | 823 | struct mem_cgroup *memcg = NULL; |
5ac8fb31 | 824 | struct mem_cgroup *pos = NULL; |
711d3d2c | 825 | |
694fbc0f AM |
826 | if (mem_cgroup_disabled()) |
827 | return NULL; | |
5660048c | 828 | |
9f3a0d09 JW |
829 | if (!root) |
830 | root = root_mem_cgroup; | |
7d74b06f | 831 | |
9f3a0d09 | 832 | if (prev && !reclaim) |
5ac8fb31 | 833 | pos = prev; |
14067bb3 | 834 | |
9f3a0d09 JW |
835 | if (!root->use_hierarchy && root != root_mem_cgroup) { |
836 | if (prev) | |
5ac8fb31 | 837 | goto out; |
694fbc0f | 838 | return root; |
9f3a0d09 | 839 | } |
14067bb3 | 840 | |
542f85f9 | 841 | rcu_read_lock(); |
5f578161 | 842 | |
5ac8fb31 JW |
843 | if (reclaim) { |
844 | struct mem_cgroup_per_zone *mz; | |
845 | ||
846 | mz = mem_cgroup_zone_zoneinfo(root, reclaim->zone); | |
847 | iter = &mz->iter[reclaim->priority]; | |
848 | ||
849 | if (prev && reclaim->generation != iter->generation) | |
850 | goto out_unlock; | |
851 | ||
6df38689 | 852 | while (1) { |
4db0c3c2 | 853 | pos = READ_ONCE(iter->position); |
6df38689 VD |
854 | if (!pos || css_tryget(&pos->css)) |
855 | break; | |
5ac8fb31 | 856 | /* |
6df38689 VD |
857 | * css reference reached zero, so iter->position will |
858 | * be cleared by ->css_released. However, we should not | |
859 | * rely on this happening soon, because ->css_released | |
860 | * is called from a work queue, and by busy-waiting we | |
861 | * might block it. So we clear iter->position right | |
862 | * away. | |
5ac8fb31 | 863 | */ |
6df38689 VD |
864 | (void)cmpxchg(&iter->position, pos, NULL); |
865 | } | |
5ac8fb31 JW |
866 | } |
867 | ||
868 | if (pos) | |
869 | css = &pos->css; | |
870 | ||
871 | for (;;) { | |
872 | css = css_next_descendant_pre(css, &root->css); | |
873 | if (!css) { | |
874 | /* | |
875 | * Reclaimers share the hierarchy walk, and a | |
876 | * new one might jump in right at the end of | |
877 | * the hierarchy - make sure they see at least | |
878 | * one group and restart from the beginning. | |
879 | */ | |
880 | if (!prev) | |
881 | continue; | |
882 | break; | |
527a5ec9 | 883 | } |
7d74b06f | 884 | |
5ac8fb31 JW |
885 | /* |
886 | * Verify the css and acquire a reference. The root | |
887 | * is provided by the caller, so we know it's alive | |
888 | * and kicking, and don't take an extra reference. | |
889 | */ | |
890 | memcg = mem_cgroup_from_css(css); | |
14067bb3 | 891 | |
5ac8fb31 JW |
892 | if (css == &root->css) |
893 | break; | |
14067bb3 | 894 | |
0b8f73e1 JW |
895 | if (css_tryget(css)) |
896 | break; | |
9f3a0d09 | 897 | |
5ac8fb31 | 898 | memcg = NULL; |
9f3a0d09 | 899 | } |
5ac8fb31 JW |
900 | |
901 | if (reclaim) { | |
5ac8fb31 | 902 | /* |
6df38689 VD |
903 | * The position could have already been updated by a competing |
904 | * thread, so check that the value hasn't changed since we read | |
905 | * it to avoid reclaiming from the same cgroup twice. | |
5ac8fb31 | 906 | */ |
6df38689 VD |
907 | (void)cmpxchg(&iter->position, pos, memcg); |
908 | ||
5ac8fb31 JW |
909 | if (pos) |
910 | css_put(&pos->css); | |
911 | ||
912 | if (!memcg) | |
913 | iter->generation++; | |
914 | else if (!prev) | |
915 | reclaim->generation = iter->generation; | |
9f3a0d09 | 916 | } |
5ac8fb31 | 917 | |
542f85f9 MH |
918 | out_unlock: |
919 | rcu_read_unlock(); | |
5ac8fb31 | 920 | out: |
c40046f3 MH |
921 | if (prev && prev != root) |
922 | css_put(&prev->css); | |
923 | ||
9f3a0d09 | 924 | return memcg; |
14067bb3 | 925 | } |
7d74b06f | 926 | |
5660048c JW |
927 | /** |
928 | * mem_cgroup_iter_break - abort a hierarchy walk prematurely | |
929 | * @root: hierarchy root | |
930 | * @prev: last visited hierarchy member as returned by mem_cgroup_iter() | |
931 | */ | |
932 | void mem_cgroup_iter_break(struct mem_cgroup *root, | |
933 | struct mem_cgroup *prev) | |
9f3a0d09 JW |
934 | { |
935 | if (!root) | |
936 | root = root_mem_cgroup; | |
937 | if (prev && prev != root) | |
938 | css_put(&prev->css); | |
939 | } | |
7d74b06f | 940 | |
6df38689 VD |
941 | static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg) |
942 | { | |
943 | struct mem_cgroup *memcg = dead_memcg; | |
944 | struct mem_cgroup_reclaim_iter *iter; | |
945 | struct mem_cgroup_per_zone *mz; | |
946 | int nid, zid; | |
947 | int i; | |
948 | ||
949 | while ((memcg = parent_mem_cgroup(memcg))) { | |
950 | for_each_node(nid) { | |
951 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
952 | mz = &memcg->nodeinfo[nid]->zoneinfo[zid]; | |
953 | for (i = 0; i <= DEF_PRIORITY; i++) { | |
954 | iter = &mz->iter[i]; | |
955 | cmpxchg(&iter->position, | |
956 | dead_memcg, NULL); | |
957 | } | |
958 | } | |
959 | } | |
960 | } | |
961 | } | |
962 | ||
9f3a0d09 JW |
963 | /* |
964 | * Iteration constructs for visiting all cgroups (under a tree). If | |
965 | * loops are exited prematurely (break), mem_cgroup_iter_break() must | |
966 | * be used for reference counting. | |
967 | */ | |
968 | #define for_each_mem_cgroup_tree(iter, root) \ | |
527a5ec9 | 969 | for (iter = mem_cgroup_iter(root, NULL, NULL); \ |
9f3a0d09 | 970 | iter != NULL; \ |
527a5ec9 | 971 | iter = mem_cgroup_iter(root, iter, NULL)) |
711d3d2c | 972 | |
9f3a0d09 | 973 | #define for_each_mem_cgroup(iter) \ |
527a5ec9 | 974 | for (iter = mem_cgroup_iter(NULL, NULL, NULL); \ |
9f3a0d09 | 975 | iter != NULL; \ |
527a5ec9 | 976 | iter = mem_cgroup_iter(NULL, iter, NULL)) |
14067bb3 | 977 | |
925b7673 JW |
978 | /** |
979 | * mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg | |
980 | * @zone: zone of the wanted lruvec | |
fa9add64 | 981 | * @memcg: memcg of the wanted lruvec |
925b7673 JW |
982 | * |
983 | * Returns the lru list vector holding pages for the given @zone and | |
984 | * @mem. This can be the global zone lruvec, if the memory controller | |
985 | * is disabled. | |
986 | */ | |
987 | struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone, | |
988 | struct mem_cgroup *memcg) | |
989 | { | |
990 | struct mem_cgroup_per_zone *mz; | |
bea8c150 | 991 | struct lruvec *lruvec; |
925b7673 | 992 | |
bea8c150 HD |
993 | if (mem_cgroup_disabled()) { |
994 | lruvec = &zone->lruvec; | |
995 | goto out; | |
996 | } | |
925b7673 | 997 | |
e231875b | 998 | mz = mem_cgroup_zone_zoneinfo(memcg, zone); |
bea8c150 HD |
999 | lruvec = &mz->lruvec; |
1000 | out: | |
1001 | /* | |
1002 | * Since a node can be onlined after the mem_cgroup was created, | |
1003 | * we have to be prepared to initialize lruvec->zone here; | |
1004 | * and if offlined then reonlined, we need to reinitialize it. | |
1005 | */ | |
1006 | if (unlikely(lruvec->zone != zone)) | |
1007 | lruvec->zone = zone; | |
1008 | return lruvec; | |
925b7673 JW |
1009 | } |
1010 | ||
925b7673 | 1011 | /** |
dfe0e773 | 1012 | * mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page |
925b7673 | 1013 | * @page: the page |
fa9add64 | 1014 | * @zone: zone of the page |
dfe0e773 JW |
1015 | * |
1016 | * This function is only safe when following the LRU page isolation | |
1017 | * and putback protocol: the LRU lock must be held, and the page must | |
1018 | * either be PageLRU() or the caller must have isolated/allocated it. | |
925b7673 | 1019 | */ |
fa9add64 | 1020 | struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct zone *zone) |
08e552c6 | 1021 | { |
08e552c6 | 1022 | struct mem_cgroup_per_zone *mz; |
925b7673 | 1023 | struct mem_cgroup *memcg; |
bea8c150 | 1024 | struct lruvec *lruvec; |
6d12e2d8 | 1025 | |
bea8c150 HD |
1026 | if (mem_cgroup_disabled()) { |
1027 | lruvec = &zone->lruvec; | |
1028 | goto out; | |
1029 | } | |
925b7673 | 1030 | |
1306a85a | 1031 | memcg = page->mem_cgroup; |
7512102c | 1032 | /* |
dfe0e773 | 1033 | * Swapcache readahead pages are added to the LRU - and |
29833315 | 1034 | * possibly migrated - before they are charged. |
7512102c | 1035 | */ |
29833315 JW |
1036 | if (!memcg) |
1037 | memcg = root_mem_cgroup; | |
7512102c | 1038 | |
e231875b | 1039 | mz = mem_cgroup_page_zoneinfo(memcg, page); |
bea8c150 HD |
1040 | lruvec = &mz->lruvec; |
1041 | out: | |
1042 | /* | |
1043 | * Since a node can be onlined after the mem_cgroup was created, | |
1044 | * we have to be prepared to initialize lruvec->zone here; | |
1045 | * and if offlined then reonlined, we need to reinitialize it. | |
1046 | */ | |
1047 | if (unlikely(lruvec->zone != zone)) | |
1048 | lruvec->zone = zone; | |
1049 | return lruvec; | |
08e552c6 | 1050 | } |
b69408e8 | 1051 | |
925b7673 | 1052 | /** |
fa9add64 HD |
1053 | * mem_cgroup_update_lru_size - account for adding or removing an lru page |
1054 | * @lruvec: mem_cgroup per zone lru vector | |
1055 | * @lru: index of lru list the page is sitting on | |
1056 | * @nr_pages: positive when adding or negative when removing | |
925b7673 | 1057 | * |
fa9add64 HD |
1058 | * This function must be called when a page is added to or removed from an |
1059 | * lru list. | |
3f58a829 | 1060 | */ |
fa9add64 HD |
1061 | void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, |
1062 | int nr_pages) | |
3f58a829 MK |
1063 | { |
1064 | struct mem_cgroup_per_zone *mz; | |
fa9add64 | 1065 | unsigned long *lru_size; |
3f58a829 MK |
1066 | |
1067 | if (mem_cgroup_disabled()) | |
1068 | return; | |
1069 | ||
fa9add64 HD |
1070 | mz = container_of(lruvec, struct mem_cgroup_per_zone, lruvec); |
1071 | lru_size = mz->lru_size + lru; | |
1072 | *lru_size += nr_pages; | |
1073 | VM_BUG_ON((long)(*lru_size) < 0); | |
08e552c6 | 1074 | } |
544122e5 | 1075 | |
2314b42d | 1076 | bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg) |
c3ac9a8a | 1077 | { |
2314b42d | 1078 | struct mem_cgroup *task_memcg; |
158e0a2d | 1079 | struct task_struct *p; |
ffbdccf5 | 1080 | bool ret; |
4c4a2214 | 1081 | |
158e0a2d | 1082 | p = find_lock_task_mm(task); |
de077d22 | 1083 | if (p) { |
2314b42d | 1084 | task_memcg = get_mem_cgroup_from_mm(p->mm); |
de077d22 DR |
1085 | task_unlock(p); |
1086 | } else { | |
1087 | /* | |
1088 | * All threads may have already detached their mm's, but the oom | |
1089 | * killer still needs to detect if they have already been oom | |
1090 | * killed to prevent needlessly killing additional tasks. | |
1091 | */ | |
ffbdccf5 | 1092 | rcu_read_lock(); |
2314b42d JW |
1093 | task_memcg = mem_cgroup_from_task(task); |
1094 | css_get(&task_memcg->css); | |
ffbdccf5 | 1095 | rcu_read_unlock(); |
de077d22 | 1096 | } |
2314b42d JW |
1097 | ret = mem_cgroup_is_descendant(task_memcg, memcg); |
1098 | css_put(&task_memcg->css); | |
4c4a2214 DR |
1099 | return ret; |
1100 | } | |
1101 | ||
19942822 | 1102 | /** |
9d11ea9f | 1103 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
dad7557e | 1104 | * @memcg: the memory cgroup |
19942822 | 1105 | * |
9d11ea9f | 1106 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1107 | * pages. |
19942822 | 1108 | */ |
c0ff4b85 | 1109 | static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) |
19942822 | 1110 | { |
3e32cb2e JW |
1111 | unsigned long margin = 0; |
1112 | unsigned long count; | |
1113 | unsigned long limit; | |
9d11ea9f | 1114 | |
3e32cb2e | 1115 | count = page_counter_read(&memcg->memory); |
4db0c3c2 | 1116 | limit = READ_ONCE(memcg->memory.limit); |
3e32cb2e JW |
1117 | if (count < limit) |
1118 | margin = limit - count; | |
1119 | ||
7941d214 | 1120 | if (do_memsw_account()) { |
3e32cb2e | 1121 | count = page_counter_read(&memcg->memsw); |
4db0c3c2 | 1122 | limit = READ_ONCE(memcg->memsw.limit); |
3e32cb2e JW |
1123 | if (count <= limit) |
1124 | margin = min(margin, limit - count); | |
1125 | } | |
1126 | ||
1127 | return margin; | |
19942822 JW |
1128 | } |
1129 | ||
32047e2a | 1130 | /* |
bdcbb659 | 1131 | * A routine for checking "mem" is under move_account() or not. |
32047e2a | 1132 | * |
bdcbb659 QH |
1133 | * Checking a cgroup is mc.from or mc.to or under hierarchy of |
1134 | * moving cgroups. This is for waiting at high-memory pressure | |
1135 | * caused by "move". | |
32047e2a | 1136 | */ |
c0ff4b85 | 1137 | static bool mem_cgroup_under_move(struct mem_cgroup *memcg) |
4b534334 | 1138 | { |
2bd9bb20 KH |
1139 | struct mem_cgroup *from; |
1140 | struct mem_cgroup *to; | |
4b534334 | 1141 | bool ret = false; |
2bd9bb20 KH |
1142 | /* |
1143 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1144 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1145 | */ | |
1146 | spin_lock(&mc.lock); | |
1147 | from = mc.from; | |
1148 | to = mc.to; | |
1149 | if (!from) | |
1150 | goto unlock; | |
3e92041d | 1151 | |
2314b42d JW |
1152 | ret = mem_cgroup_is_descendant(from, memcg) || |
1153 | mem_cgroup_is_descendant(to, memcg); | |
2bd9bb20 KH |
1154 | unlock: |
1155 | spin_unlock(&mc.lock); | |
4b534334 KH |
1156 | return ret; |
1157 | } | |
1158 | ||
c0ff4b85 | 1159 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) |
4b534334 KH |
1160 | { |
1161 | if (mc.moving_task && current != mc.moving_task) { | |
c0ff4b85 | 1162 | if (mem_cgroup_under_move(memcg)) { |
4b534334 KH |
1163 | DEFINE_WAIT(wait); |
1164 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1165 | /* moving charge context might have finished. */ | |
1166 | if (mc.moving_task) | |
1167 | schedule(); | |
1168 | finish_wait(&mc.waitq, &wait); | |
1169 | return true; | |
1170 | } | |
1171 | } | |
1172 | return false; | |
1173 | } | |
1174 | ||
58cf188e | 1175 | #define K(x) ((x) << (PAGE_SHIFT-10)) |
e222432b | 1176 | /** |
58cf188e | 1177 | * mem_cgroup_print_oom_info: Print OOM information relevant to memory controller. |
e222432b BS |
1178 | * @memcg: The memory cgroup that went over limit |
1179 | * @p: Task that is going to be killed | |
1180 | * | |
1181 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1182 | * enabled | |
1183 | */ | |
1184 | void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) | |
1185 | { | |
e61734c5 | 1186 | /* oom_info_lock ensures that parallel ooms do not interleave */ |
08088cb9 | 1187 | static DEFINE_MUTEX(oom_info_lock); |
58cf188e SZ |
1188 | struct mem_cgroup *iter; |
1189 | unsigned int i; | |
e222432b | 1190 | |
08088cb9 | 1191 | mutex_lock(&oom_info_lock); |
e222432b BS |
1192 | rcu_read_lock(); |
1193 | ||
2415b9f5 BV |
1194 | if (p) { |
1195 | pr_info("Task in "); | |
1196 | pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id)); | |
1197 | pr_cont(" killed as a result of limit of "); | |
1198 | } else { | |
1199 | pr_info("Memory limit reached of cgroup "); | |
1200 | } | |
1201 | ||
e61734c5 | 1202 | pr_cont_cgroup_path(memcg->css.cgroup); |
0346dadb | 1203 | pr_cont("\n"); |
e222432b | 1204 | |
e222432b BS |
1205 | rcu_read_unlock(); |
1206 | ||
3e32cb2e JW |
1207 | pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n", |
1208 | K((u64)page_counter_read(&memcg->memory)), | |
1209 | K((u64)memcg->memory.limit), memcg->memory.failcnt); | |
1210 | pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n", | |
1211 | K((u64)page_counter_read(&memcg->memsw)), | |
1212 | K((u64)memcg->memsw.limit), memcg->memsw.failcnt); | |
1213 | pr_info("kmem: usage %llukB, limit %llukB, failcnt %lu\n", | |
1214 | K((u64)page_counter_read(&memcg->kmem)), | |
1215 | K((u64)memcg->kmem.limit), memcg->kmem.failcnt); | |
58cf188e SZ |
1216 | |
1217 | for_each_mem_cgroup_tree(iter, memcg) { | |
e61734c5 TH |
1218 | pr_info("Memory cgroup stats for "); |
1219 | pr_cont_cgroup_path(iter->css.cgroup); | |
58cf188e SZ |
1220 | pr_cont(":"); |
1221 | ||
1222 | for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) { | |
7941d214 | 1223 | if (i == MEM_CGROUP_STAT_SWAP && !do_memsw_account()) |
58cf188e | 1224 | continue; |
484ebb3b | 1225 | pr_cont(" %s:%luKB", mem_cgroup_stat_names[i], |
58cf188e SZ |
1226 | K(mem_cgroup_read_stat(iter, i))); |
1227 | } | |
1228 | ||
1229 | for (i = 0; i < NR_LRU_LISTS; i++) | |
1230 | pr_cont(" %s:%luKB", mem_cgroup_lru_names[i], | |
1231 | K(mem_cgroup_nr_lru_pages(iter, BIT(i)))); | |
1232 | ||
1233 | pr_cont("\n"); | |
1234 | } | |
08088cb9 | 1235 | mutex_unlock(&oom_info_lock); |
e222432b BS |
1236 | } |
1237 | ||
81d39c20 KH |
1238 | /* |
1239 | * This function returns the number of memcg under hierarchy tree. Returns | |
1240 | * 1(self count) if no children. | |
1241 | */ | |
c0ff4b85 | 1242 | static int mem_cgroup_count_children(struct mem_cgroup *memcg) |
81d39c20 KH |
1243 | { |
1244 | int num = 0; | |
7d74b06f KH |
1245 | struct mem_cgroup *iter; |
1246 | ||
c0ff4b85 | 1247 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 1248 | num++; |
81d39c20 KH |
1249 | return num; |
1250 | } | |
1251 | ||
a63d83f4 DR |
1252 | /* |
1253 | * Return the memory (and swap, if configured) limit for a memcg. | |
1254 | */ | |
3e32cb2e | 1255 | static unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg) |
a63d83f4 | 1256 | { |
3e32cb2e | 1257 | unsigned long limit; |
f3e8eb70 | 1258 | |
3e32cb2e | 1259 | limit = memcg->memory.limit; |
9a5a8f19 | 1260 | if (mem_cgroup_swappiness(memcg)) { |
3e32cb2e | 1261 | unsigned long memsw_limit; |
9a5a8f19 | 1262 | |
3e32cb2e JW |
1263 | memsw_limit = memcg->memsw.limit; |
1264 | limit = min(limit + total_swap_pages, memsw_limit); | |
9a5a8f19 | 1265 | } |
9a5a8f19 | 1266 | return limit; |
a63d83f4 DR |
1267 | } |
1268 | ||
19965460 DR |
1269 | static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, |
1270 | int order) | |
9cbb78bb | 1271 | { |
6e0fc46d DR |
1272 | struct oom_control oc = { |
1273 | .zonelist = NULL, | |
1274 | .nodemask = NULL, | |
1275 | .gfp_mask = gfp_mask, | |
1276 | .order = order, | |
6e0fc46d | 1277 | }; |
9cbb78bb DR |
1278 | struct mem_cgroup *iter; |
1279 | unsigned long chosen_points = 0; | |
1280 | unsigned long totalpages; | |
1281 | unsigned int points = 0; | |
1282 | struct task_struct *chosen = NULL; | |
1283 | ||
dc56401f JW |
1284 | mutex_lock(&oom_lock); |
1285 | ||
876aafbf | 1286 | /* |
465adcf1 DR |
1287 | * If current has a pending SIGKILL or is exiting, then automatically |
1288 | * select it. The goal is to allow it to allocate so that it may | |
1289 | * quickly exit and free its memory. | |
876aafbf | 1290 | */ |
d003f371 | 1291 | if (fatal_signal_pending(current) || task_will_free_mem(current)) { |
16e95196 | 1292 | mark_oom_victim(current); |
dc56401f | 1293 | goto unlock; |
876aafbf DR |
1294 | } |
1295 | ||
6e0fc46d | 1296 | check_panic_on_oom(&oc, CONSTRAINT_MEMCG, memcg); |
3e32cb2e | 1297 | totalpages = mem_cgroup_get_limit(memcg) ? : 1; |
9cbb78bb | 1298 | for_each_mem_cgroup_tree(iter, memcg) { |
72ec7029 | 1299 | struct css_task_iter it; |
9cbb78bb DR |
1300 | struct task_struct *task; |
1301 | ||
72ec7029 TH |
1302 | css_task_iter_start(&iter->css, &it); |
1303 | while ((task = css_task_iter_next(&it))) { | |
6e0fc46d | 1304 | switch (oom_scan_process_thread(&oc, task, totalpages)) { |
9cbb78bb DR |
1305 | case OOM_SCAN_SELECT: |
1306 | if (chosen) | |
1307 | put_task_struct(chosen); | |
1308 | chosen = task; | |
1309 | chosen_points = ULONG_MAX; | |
1310 | get_task_struct(chosen); | |
1311 | /* fall through */ | |
1312 | case OOM_SCAN_CONTINUE: | |
1313 | continue; | |
1314 | case OOM_SCAN_ABORT: | |
72ec7029 | 1315 | css_task_iter_end(&it); |
9cbb78bb DR |
1316 | mem_cgroup_iter_break(memcg, iter); |
1317 | if (chosen) | |
1318 | put_task_struct(chosen); | |
dc56401f | 1319 | goto unlock; |
9cbb78bb DR |
1320 | case OOM_SCAN_OK: |
1321 | break; | |
1322 | }; | |
1323 | points = oom_badness(task, memcg, NULL, totalpages); | |
d49ad935 DR |
1324 | if (!points || points < chosen_points) |
1325 | continue; | |
1326 | /* Prefer thread group leaders for display purposes */ | |
1327 | if (points == chosen_points && | |
1328 | thread_group_leader(chosen)) | |
1329 | continue; | |
1330 | ||
1331 | if (chosen) | |
1332 | put_task_struct(chosen); | |
1333 | chosen = task; | |
1334 | chosen_points = points; | |
1335 | get_task_struct(chosen); | |
9cbb78bb | 1336 | } |
72ec7029 | 1337 | css_task_iter_end(&it); |
9cbb78bb DR |
1338 | } |
1339 | ||
dc56401f JW |
1340 | if (chosen) { |
1341 | points = chosen_points * 1000 / totalpages; | |
6e0fc46d DR |
1342 | oom_kill_process(&oc, chosen, points, totalpages, memcg, |
1343 | "Memory cgroup out of memory"); | |
dc56401f JW |
1344 | } |
1345 | unlock: | |
1346 | mutex_unlock(&oom_lock); | |
9cbb78bb DR |
1347 | } |
1348 | ||
ae6e71d3 MC |
1349 | #if MAX_NUMNODES > 1 |
1350 | ||
4d0c066d KH |
1351 | /** |
1352 | * test_mem_cgroup_node_reclaimable | |
dad7557e | 1353 | * @memcg: the target memcg |
4d0c066d KH |
1354 | * @nid: the node ID to be checked. |
1355 | * @noswap : specify true here if the user wants flle only information. | |
1356 | * | |
1357 | * This function returns whether the specified memcg contains any | |
1358 | * reclaimable pages on a node. Returns true if there are any reclaimable | |
1359 | * pages in the node. | |
1360 | */ | |
c0ff4b85 | 1361 | static bool test_mem_cgroup_node_reclaimable(struct mem_cgroup *memcg, |
4d0c066d KH |
1362 | int nid, bool noswap) |
1363 | { | |
c0ff4b85 | 1364 | if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_FILE)) |
4d0c066d KH |
1365 | return true; |
1366 | if (noswap || !total_swap_pages) | |
1367 | return false; | |
c0ff4b85 | 1368 | if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_ANON)) |
4d0c066d KH |
1369 | return true; |
1370 | return false; | |
1371 | ||
1372 | } | |
889976db YH |
1373 | |
1374 | /* | |
1375 | * Always updating the nodemask is not very good - even if we have an empty | |
1376 | * list or the wrong list here, we can start from some node and traverse all | |
1377 | * nodes based on the zonelist. So update the list loosely once per 10 secs. | |
1378 | * | |
1379 | */ | |
c0ff4b85 | 1380 | static void mem_cgroup_may_update_nodemask(struct mem_cgroup *memcg) |
889976db YH |
1381 | { |
1382 | int nid; | |
453a9bf3 KH |
1383 | /* |
1384 | * numainfo_events > 0 means there was at least NUMAINFO_EVENTS_TARGET | |
1385 | * pagein/pageout changes since the last update. | |
1386 | */ | |
c0ff4b85 | 1387 | if (!atomic_read(&memcg->numainfo_events)) |
453a9bf3 | 1388 | return; |
c0ff4b85 | 1389 | if (atomic_inc_return(&memcg->numainfo_updating) > 1) |
889976db YH |
1390 | return; |
1391 | ||
889976db | 1392 | /* make a nodemask where this memcg uses memory from */ |
31aaea4a | 1393 | memcg->scan_nodes = node_states[N_MEMORY]; |
889976db | 1394 | |
31aaea4a | 1395 | for_each_node_mask(nid, node_states[N_MEMORY]) { |
889976db | 1396 | |
c0ff4b85 R |
1397 | if (!test_mem_cgroup_node_reclaimable(memcg, nid, false)) |
1398 | node_clear(nid, memcg->scan_nodes); | |
889976db | 1399 | } |
453a9bf3 | 1400 | |
c0ff4b85 R |
1401 | atomic_set(&memcg->numainfo_events, 0); |
1402 | atomic_set(&memcg->numainfo_updating, 0); | |
889976db YH |
1403 | } |
1404 | ||
1405 | /* | |
1406 | * Selecting a node where we start reclaim from. Because what we need is just | |
1407 | * reducing usage counter, start from anywhere is O,K. Considering | |
1408 | * memory reclaim from current node, there are pros. and cons. | |
1409 | * | |
1410 | * Freeing memory from current node means freeing memory from a node which | |
1411 | * we'll use or we've used. So, it may make LRU bad. And if several threads | |
1412 | * hit limits, it will see a contention on a node. But freeing from remote | |
1413 | * node means more costs for memory reclaim because of memory latency. | |
1414 | * | |
1415 | * Now, we use round-robin. Better algorithm is welcomed. | |
1416 | */ | |
c0ff4b85 | 1417 | int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) |
889976db YH |
1418 | { |
1419 | int node; | |
1420 | ||
c0ff4b85 R |
1421 | mem_cgroup_may_update_nodemask(memcg); |
1422 | node = memcg->last_scanned_node; | |
889976db | 1423 | |
c0ff4b85 | 1424 | node = next_node(node, memcg->scan_nodes); |
889976db | 1425 | if (node == MAX_NUMNODES) |
c0ff4b85 | 1426 | node = first_node(memcg->scan_nodes); |
889976db YH |
1427 | /* |
1428 | * We call this when we hit limit, not when pages are added to LRU. | |
1429 | * No LRU may hold pages because all pages are UNEVICTABLE or | |
1430 | * memcg is too small and all pages are not on LRU. In that case, | |
1431 | * we use curret node. | |
1432 | */ | |
1433 | if (unlikely(node == MAX_NUMNODES)) | |
1434 | node = numa_node_id(); | |
1435 | ||
c0ff4b85 | 1436 | memcg->last_scanned_node = node; |
889976db YH |
1437 | return node; |
1438 | } | |
889976db | 1439 | #else |
c0ff4b85 | 1440 | int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) |
889976db YH |
1441 | { |
1442 | return 0; | |
1443 | } | |
1444 | #endif | |
1445 | ||
0608f43d AM |
1446 | static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, |
1447 | struct zone *zone, | |
1448 | gfp_t gfp_mask, | |
1449 | unsigned long *total_scanned) | |
1450 | { | |
1451 | struct mem_cgroup *victim = NULL; | |
1452 | int total = 0; | |
1453 | int loop = 0; | |
1454 | unsigned long excess; | |
1455 | unsigned long nr_scanned; | |
1456 | struct mem_cgroup_reclaim_cookie reclaim = { | |
1457 | .zone = zone, | |
1458 | .priority = 0, | |
1459 | }; | |
1460 | ||
3e32cb2e | 1461 | excess = soft_limit_excess(root_memcg); |
0608f43d AM |
1462 | |
1463 | while (1) { | |
1464 | victim = mem_cgroup_iter(root_memcg, victim, &reclaim); | |
1465 | if (!victim) { | |
1466 | loop++; | |
1467 | if (loop >= 2) { | |
1468 | /* | |
1469 | * If we have not been able to reclaim | |
1470 | * anything, it might because there are | |
1471 | * no reclaimable pages under this hierarchy | |
1472 | */ | |
1473 | if (!total) | |
1474 | break; | |
1475 | /* | |
1476 | * We want to do more targeted reclaim. | |
1477 | * excess >> 2 is not to excessive so as to | |
1478 | * reclaim too much, nor too less that we keep | |
1479 | * coming back to reclaim from this cgroup | |
1480 | */ | |
1481 | if (total >= (excess >> 2) || | |
1482 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) | |
1483 | break; | |
1484 | } | |
1485 | continue; | |
1486 | } | |
0608f43d AM |
1487 | total += mem_cgroup_shrink_node_zone(victim, gfp_mask, false, |
1488 | zone, &nr_scanned); | |
1489 | *total_scanned += nr_scanned; | |
3e32cb2e | 1490 | if (!soft_limit_excess(root_memcg)) |
0608f43d | 1491 | break; |
6d61ef40 | 1492 | } |
0608f43d AM |
1493 | mem_cgroup_iter_break(root_memcg, victim); |
1494 | return total; | |
6d61ef40 BS |
1495 | } |
1496 | ||
0056f4e6 JW |
1497 | #ifdef CONFIG_LOCKDEP |
1498 | static struct lockdep_map memcg_oom_lock_dep_map = { | |
1499 | .name = "memcg_oom_lock", | |
1500 | }; | |
1501 | #endif | |
1502 | ||
fb2a6fc5 JW |
1503 | static DEFINE_SPINLOCK(memcg_oom_lock); |
1504 | ||
867578cb KH |
1505 | /* |
1506 | * Check OOM-Killer is already running under our hierarchy. | |
1507 | * If someone is running, return false. | |
1508 | */ | |
fb2a6fc5 | 1509 | static bool mem_cgroup_oom_trylock(struct mem_cgroup *memcg) |
867578cb | 1510 | { |
79dfdacc | 1511 | struct mem_cgroup *iter, *failed = NULL; |
a636b327 | 1512 | |
fb2a6fc5 JW |
1513 | spin_lock(&memcg_oom_lock); |
1514 | ||
9f3a0d09 | 1515 | for_each_mem_cgroup_tree(iter, memcg) { |
23751be0 | 1516 | if (iter->oom_lock) { |
79dfdacc MH |
1517 | /* |
1518 | * this subtree of our hierarchy is already locked | |
1519 | * so we cannot give a lock. | |
1520 | */ | |
79dfdacc | 1521 | failed = iter; |
9f3a0d09 JW |
1522 | mem_cgroup_iter_break(memcg, iter); |
1523 | break; | |
23751be0 JW |
1524 | } else |
1525 | iter->oom_lock = true; | |
7d74b06f | 1526 | } |
867578cb | 1527 | |
fb2a6fc5 JW |
1528 | if (failed) { |
1529 | /* | |
1530 | * OK, we failed to lock the whole subtree so we have | |
1531 | * to clean up what we set up to the failing subtree | |
1532 | */ | |
1533 | for_each_mem_cgroup_tree(iter, memcg) { | |
1534 | if (iter == failed) { | |
1535 | mem_cgroup_iter_break(memcg, iter); | |
1536 | break; | |
1537 | } | |
1538 | iter->oom_lock = false; | |
79dfdacc | 1539 | } |
0056f4e6 JW |
1540 | } else |
1541 | mutex_acquire(&memcg_oom_lock_dep_map, 0, 1, _RET_IP_); | |
fb2a6fc5 JW |
1542 | |
1543 | spin_unlock(&memcg_oom_lock); | |
1544 | ||
1545 | return !failed; | |
a636b327 | 1546 | } |
0b7f569e | 1547 | |
fb2a6fc5 | 1548 | static void mem_cgroup_oom_unlock(struct mem_cgroup *memcg) |
0b7f569e | 1549 | { |
7d74b06f KH |
1550 | struct mem_cgroup *iter; |
1551 | ||
fb2a6fc5 | 1552 | spin_lock(&memcg_oom_lock); |
0056f4e6 | 1553 | mutex_release(&memcg_oom_lock_dep_map, 1, _RET_IP_); |
c0ff4b85 | 1554 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc | 1555 | iter->oom_lock = false; |
fb2a6fc5 | 1556 | spin_unlock(&memcg_oom_lock); |
79dfdacc MH |
1557 | } |
1558 | ||
c0ff4b85 | 1559 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1560 | { |
1561 | struct mem_cgroup *iter; | |
1562 | ||
c2b42d3c | 1563 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1564 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1565 | iter->under_oom++; |
1566 | spin_unlock(&memcg_oom_lock); | |
79dfdacc MH |
1567 | } |
1568 | ||
c0ff4b85 | 1569 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1570 | { |
1571 | struct mem_cgroup *iter; | |
1572 | ||
867578cb KH |
1573 | /* |
1574 | * When a new child is created while the hierarchy is under oom, | |
c2b42d3c | 1575 | * mem_cgroup_oom_lock() may not be called. Watch for underflow. |
867578cb | 1576 | */ |
c2b42d3c | 1577 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1578 | for_each_mem_cgroup_tree(iter, memcg) |
c2b42d3c TH |
1579 | if (iter->under_oom > 0) |
1580 | iter->under_oom--; | |
1581 | spin_unlock(&memcg_oom_lock); | |
0b7f569e KH |
1582 | } |
1583 | ||
867578cb KH |
1584 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1585 | ||
dc98df5a | 1586 | struct oom_wait_info { |
d79154bb | 1587 | struct mem_cgroup *memcg; |
dc98df5a KH |
1588 | wait_queue_t wait; |
1589 | }; | |
1590 | ||
1591 | static int memcg_oom_wake_function(wait_queue_t *wait, | |
1592 | unsigned mode, int sync, void *arg) | |
1593 | { | |
d79154bb HD |
1594 | struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg; |
1595 | struct mem_cgroup *oom_wait_memcg; | |
dc98df5a KH |
1596 | struct oom_wait_info *oom_wait_info; |
1597 | ||
1598 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
d79154bb | 1599 | oom_wait_memcg = oom_wait_info->memcg; |
dc98df5a | 1600 | |
2314b42d JW |
1601 | if (!mem_cgroup_is_descendant(wake_memcg, oom_wait_memcg) && |
1602 | !mem_cgroup_is_descendant(oom_wait_memcg, wake_memcg)) | |
dc98df5a | 1603 | return 0; |
dc98df5a KH |
1604 | return autoremove_wake_function(wait, mode, sync, arg); |
1605 | } | |
1606 | ||
c0ff4b85 | 1607 | static void memcg_oom_recover(struct mem_cgroup *memcg) |
3c11ecf4 | 1608 | { |
c2b42d3c TH |
1609 | /* |
1610 | * For the following lockless ->under_oom test, the only required | |
1611 | * guarantee is that it must see the state asserted by an OOM when | |
1612 | * this function is called as a result of userland actions | |
1613 | * triggered by the notification of the OOM. This is trivially | |
1614 | * achieved by invoking mem_cgroup_mark_under_oom() before | |
1615 | * triggering notification. | |
1616 | */ | |
1617 | if (memcg && memcg->under_oom) | |
f4b90b70 | 1618 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg); |
3c11ecf4 KH |
1619 | } |
1620 | ||
3812c8c8 | 1621 | static void mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order) |
0b7f569e | 1622 | { |
626ebc41 | 1623 | if (!current->memcg_may_oom) |
3812c8c8 | 1624 | return; |
867578cb | 1625 | /* |
49426420 JW |
1626 | * We are in the middle of the charge context here, so we |
1627 | * don't want to block when potentially sitting on a callstack | |
1628 | * that holds all kinds of filesystem and mm locks. | |
1629 | * | |
1630 | * Also, the caller may handle a failed allocation gracefully | |
1631 | * (like optional page cache readahead) and so an OOM killer | |
1632 | * invocation might not even be necessary. | |
1633 | * | |
1634 | * That's why we don't do anything here except remember the | |
1635 | * OOM context and then deal with it at the end of the page | |
1636 | * fault when the stack is unwound, the locks are released, | |
1637 | * and when we know whether the fault was overall successful. | |
867578cb | 1638 | */ |
49426420 | 1639 | css_get(&memcg->css); |
626ebc41 TH |
1640 | current->memcg_in_oom = memcg; |
1641 | current->memcg_oom_gfp_mask = mask; | |
1642 | current->memcg_oom_order = order; | |
3812c8c8 JW |
1643 | } |
1644 | ||
1645 | /** | |
1646 | * mem_cgroup_oom_synchronize - complete memcg OOM handling | |
49426420 | 1647 | * @handle: actually kill/wait or just clean up the OOM state |
3812c8c8 | 1648 | * |
49426420 JW |
1649 | * This has to be called at the end of a page fault if the memcg OOM |
1650 | * handler was enabled. | |
3812c8c8 | 1651 | * |
49426420 | 1652 | * Memcg supports userspace OOM handling where failed allocations must |
3812c8c8 JW |
1653 | * sleep on a waitqueue until the userspace task resolves the |
1654 | * situation. Sleeping directly in the charge context with all kinds | |
1655 | * of locks held is not a good idea, instead we remember an OOM state | |
1656 | * in the task and mem_cgroup_oom_synchronize() has to be called at | |
49426420 | 1657 | * the end of the page fault to complete the OOM handling. |
3812c8c8 JW |
1658 | * |
1659 | * Returns %true if an ongoing memcg OOM situation was detected and | |
49426420 | 1660 | * completed, %false otherwise. |
3812c8c8 | 1661 | */ |
49426420 | 1662 | bool mem_cgroup_oom_synchronize(bool handle) |
3812c8c8 | 1663 | { |
626ebc41 | 1664 | struct mem_cgroup *memcg = current->memcg_in_oom; |
3812c8c8 | 1665 | struct oom_wait_info owait; |
49426420 | 1666 | bool locked; |
3812c8c8 JW |
1667 | |
1668 | /* OOM is global, do not handle */ | |
3812c8c8 | 1669 | if (!memcg) |
49426420 | 1670 | return false; |
3812c8c8 | 1671 | |
c32b3cbe | 1672 | if (!handle || oom_killer_disabled) |
49426420 | 1673 | goto cleanup; |
3812c8c8 JW |
1674 | |
1675 | owait.memcg = memcg; | |
1676 | owait.wait.flags = 0; | |
1677 | owait.wait.func = memcg_oom_wake_function; | |
1678 | owait.wait.private = current; | |
1679 | INIT_LIST_HEAD(&owait.wait.task_list); | |
867578cb | 1680 | |
3812c8c8 | 1681 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
49426420 JW |
1682 | mem_cgroup_mark_under_oom(memcg); |
1683 | ||
1684 | locked = mem_cgroup_oom_trylock(memcg); | |
1685 | ||
1686 | if (locked) | |
1687 | mem_cgroup_oom_notify(memcg); | |
1688 | ||
1689 | if (locked && !memcg->oom_kill_disable) { | |
1690 | mem_cgroup_unmark_under_oom(memcg); | |
1691 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
626ebc41 TH |
1692 | mem_cgroup_out_of_memory(memcg, current->memcg_oom_gfp_mask, |
1693 | current->memcg_oom_order); | |
49426420 | 1694 | } else { |
3812c8c8 | 1695 | schedule(); |
49426420 JW |
1696 | mem_cgroup_unmark_under_oom(memcg); |
1697 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
1698 | } | |
1699 | ||
1700 | if (locked) { | |
fb2a6fc5 JW |
1701 | mem_cgroup_oom_unlock(memcg); |
1702 | /* | |
1703 | * There is no guarantee that an OOM-lock contender | |
1704 | * sees the wakeups triggered by the OOM kill | |
1705 | * uncharges. Wake any sleepers explicitely. | |
1706 | */ | |
1707 | memcg_oom_recover(memcg); | |
1708 | } | |
49426420 | 1709 | cleanup: |
626ebc41 | 1710 | current->memcg_in_oom = NULL; |
3812c8c8 | 1711 | css_put(&memcg->css); |
867578cb | 1712 | return true; |
0b7f569e KH |
1713 | } |
1714 | ||
d7365e78 JW |
1715 | /** |
1716 | * mem_cgroup_begin_page_stat - begin a page state statistics transaction | |
1717 | * @page: page that is going to change accounted state | |
32047e2a | 1718 | * |
d7365e78 JW |
1719 | * This function must mark the beginning of an accounted page state |
1720 | * change to prevent double accounting when the page is concurrently | |
1721 | * being moved to another memcg: | |
32047e2a | 1722 | * |
6de22619 | 1723 | * memcg = mem_cgroup_begin_page_stat(page); |
d7365e78 JW |
1724 | * if (TestClearPageState(page)) |
1725 | * mem_cgroup_update_page_stat(memcg, state, -1); | |
6de22619 | 1726 | * mem_cgroup_end_page_stat(memcg); |
d69b042f | 1727 | */ |
6de22619 | 1728 | struct mem_cgroup *mem_cgroup_begin_page_stat(struct page *page) |
89c06bd5 KH |
1729 | { |
1730 | struct mem_cgroup *memcg; | |
6de22619 | 1731 | unsigned long flags; |
89c06bd5 | 1732 | |
6de22619 JW |
1733 | /* |
1734 | * The RCU lock is held throughout the transaction. The fast | |
1735 | * path can get away without acquiring the memcg->move_lock | |
1736 | * because page moving starts with an RCU grace period. | |
1737 | * | |
1738 | * The RCU lock also protects the memcg from being freed when | |
1739 | * the page state that is going to change is the only thing | |
1740 | * preventing the page from being uncharged. | |
1741 | * E.g. end-writeback clearing PageWriteback(), which allows | |
1742 | * migration to go ahead and uncharge the page before the | |
1743 | * account transaction might be complete. | |
1744 | */ | |
d7365e78 JW |
1745 | rcu_read_lock(); |
1746 | ||
1747 | if (mem_cgroup_disabled()) | |
1748 | return NULL; | |
89c06bd5 | 1749 | again: |
1306a85a | 1750 | memcg = page->mem_cgroup; |
29833315 | 1751 | if (unlikely(!memcg)) |
d7365e78 JW |
1752 | return NULL; |
1753 | ||
bdcbb659 | 1754 | if (atomic_read(&memcg->moving_account) <= 0) |
d7365e78 | 1755 | return memcg; |
89c06bd5 | 1756 | |
6de22619 | 1757 | spin_lock_irqsave(&memcg->move_lock, flags); |
1306a85a | 1758 | if (memcg != page->mem_cgroup) { |
6de22619 | 1759 | spin_unlock_irqrestore(&memcg->move_lock, flags); |
89c06bd5 KH |
1760 | goto again; |
1761 | } | |
6de22619 JW |
1762 | |
1763 | /* | |
1764 | * When charge migration first begins, we can have locked and | |
1765 | * unlocked page stat updates happening concurrently. Track | |
1766 | * the task who has the lock for mem_cgroup_end_page_stat(). | |
1767 | */ | |
1768 | memcg->move_lock_task = current; | |
1769 | memcg->move_lock_flags = flags; | |
d7365e78 JW |
1770 | |
1771 | return memcg; | |
89c06bd5 | 1772 | } |
c4843a75 | 1773 | EXPORT_SYMBOL(mem_cgroup_begin_page_stat); |
89c06bd5 | 1774 | |
d7365e78 JW |
1775 | /** |
1776 | * mem_cgroup_end_page_stat - finish a page state statistics transaction | |
1777 | * @memcg: the memcg that was accounted against | |
d7365e78 | 1778 | */ |
6de22619 | 1779 | void mem_cgroup_end_page_stat(struct mem_cgroup *memcg) |
89c06bd5 | 1780 | { |
6de22619 JW |
1781 | if (memcg && memcg->move_lock_task == current) { |
1782 | unsigned long flags = memcg->move_lock_flags; | |
1783 | ||
1784 | memcg->move_lock_task = NULL; | |
1785 | memcg->move_lock_flags = 0; | |
1786 | ||
1787 | spin_unlock_irqrestore(&memcg->move_lock, flags); | |
1788 | } | |
89c06bd5 | 1789 | |
d7365e78 | 1790 | rcu_read_unlock(); |
89c06bd5 | 1791 | } |
c4843a75 | 1792 | EXPORT_SYMBOL(mem_cgroup_end_page_stat); |
89c06bd5 | 1793 | |
cdec2e42 KH |
1794 | /* |
1795 | * size of first charge trial. "32" comes from vmscan.c's magic value. | |
1796 | * TODO: maybe necessary to use big numbers in big irons. | |
1797 | */ | |
7ec99d62 | 1798 | #define CHARGE_BATCH 32U |
cdec2e42 KH |
1799 | struct memcg_stock_pcp { |
1800 | struct mem_cgroup *cached; /* this never be root cgroup */ | |
11c9ea4e | 1801 | unsigned int nr_pages; |
cdec2e42 | 1802 | struct work_struct work; |
26fe6168 | 1803 | unsigned long flags; |
a0db00fc | 1804 | #define FLUSHING_CACHED_CHARGE 0 |
cdec2e42 KH |
1805 | }; |
1806 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); | |
9f50fad6 | 1807 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 | 1808 | |
a0956d54 SS |
1809 | /** |
1810 | * consume_stock: Try to consume stocked charge on this cpu. | |
1811 | * @memcg: memcg to consume from. | |
1812 | * @nr_pages: how many pages to charge. | |
1813 | * | |
1814 | * The charges will only happen if @memcg matches the current cpu's memcg | |
1815 | * stock, and at least @nr_pages are available in that stock. Failure to | |
1816 | * service an allocation will refill the stock. | |
1817 | * | |
1818 | * returns true if successful, false otherwise. | |
cdec2e42 | 1819 | */ |
a0956d54 | 1820 | static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
1821 | { |
1822 | struct memcg_stock_pcp *stock; | |
3e32cb2e | 1823 | bool ret = false; |
cdec2e42 | 1824 | |
a0956d54 | 1825 | if (nr_pages > CHARGE_BATCH) |
3e32cb2e | 1826 | return ret; |
a0956d54 | 1827 | |
cdec2e42 | 1828 | stock = &get_cpu_var(memcg_stock); |
3e32cb2e | 1829 | if (memcg == stock->cached && stock->nr_pages >= nr_pages) { |
a0956d54 | 1830 | stock->nr_pages -= nr_pages; |
3e32cb2e JW |
1831 | ret = true; |
1832 | } | |
cdec2e42 KH |
1833 | put_cpu_var(memcg_stock); |
1834 | return ret; | |
1835 | } | |
1836 | ||
1837 | /* | |
3e32cb2e | 1838 | * Returns stocks cached in percpu and reset cached information. |
cdec2e42 KH |
1839 | */ |
1840 | static void drain_stock(struct memcg_stock_pcp *stock) | |
1841 | { | |
1842 | struct mem_cgroup *old = stock->cached; | |
1843 | ||
11c9ea4e | 1844 | if (stock->nr_pages) { |
3e32cb2e | 1845 | page_counter_uncharge(&old->memory, stock->nr_pages); |
7941d214 | 1846 | if (do_memsw_account()) |
3e32cb2e | 1847 | page_counter_uncharge(&old->memsw, stock->nr_pages); |
e8ea14cc | 1848 | css_put_many(&old->css, stock->nr_pages); |
11c9ea4e | 1849 | stock->nr_pages = 0; |
cdec2e42 KH |
1850 | } |
1851 | stock->cached = NULL; | |
cdec2e42 KH |
1852 | } |
1853 | ||
1854 | /* | |
1855 | * This must be called under preempt disabled or must be called by | |
1856 | * a thread which is pinned to local cpu. | |
1857 | */ | |
1858 | static void drain_local_stock(struct work_struct *dummy) | |
1859 | { | |
7c8e0181 | 1860 | struct memcg_stock_pcp *stock = this_cpu_ptr(&memcg_stock); |
cdec2e42 | 1861 | drain_stock(stock); |
26fe6168 | 1862 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
cdec2e42 KH |
1863 | } |
1864 | ||
1865 | /* | |
3e32cb2e | 1866 | * Cache charges(val) to local per_cpu area. |
320cc51d | 1867 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 1868 | */ |
c0ff4b85 | 1869 | static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
1870 | { |
1871 | struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock); | |
1872 | ||
c0ff4b85 | 1873 | if (stock->cached != memcg) { /* reset if necessary */ |
cdec2e42 | 1874 | drain_stock(stock); |
c0ff4b85 | 1875 | stock->cached = memcg; |
cdec2e42 | 1876 | } |
11c9ea4e | 1877 | stock->nr_pages += nr_pages; |
cdec2e42 KH |
1878 | put_cpu_var(memcg_stock); |
1879 | } | |
1880 | ||
1881 | /* | |
c0ff4b85 | 1882 | * Drains all per-CPU charge caches for given root_memcg resp. subtree |
6d3d6aa2 | 1883 | * of the hierarchy under it. |
cdec2e42 | 1884 | */ |
6d3d6aa2 | 1885 | static void drain_all_stock(struct mem_cgroup *root_memcg) |
cdec2e42 | 1886 | { |
26fe6168 | 1887 | int cpu, curcpu; |
d38144b7 | 1888 | |
6d3d6aa2 JW |
1889 | /* If someone's already draining, avoid adding running more workers. */ |
1890 | if (!mutex_trylock(&percpu_charge_mutex)) | |
1891 | return; | |
cdec2e42 | 1892 | /* Notify other cpus that system-wide "drain" is running */ |
cdec2e42 | 1893 | get_online_cpus(); |
5af12d0e | 1894 | curcpu = get_cpu(); |
cdec2e42 KH |
1895 | for_each_online_cpu(cpu) { |
1896 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
c0ff4b85 | 1897 | struct mem_cgroup *memcg; |
26fe6168 | 1898 | |
c0ff4b85 R |
1899 | memcg = stock->cached; |
1900 | if (!memcg || !stock->nr_pages) | |
26fe6168 | 1901 | continue; |
2314b42d | 1902 | if (!mem_cgroup_is_descendant(memcg, root_memcg)) |
3e92041d | 1903 | continue; |
d1a05b69 MH |
1904 | if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { |
1905 | if (cpu == curcpu) | |
1906 | drain_local_stock(&stock->work); | |
1907 | else | |
1908 | schedule_work_on(cpu, &stock->work); | |
1909 | } | |
cdec2e42 | 1910 | } |
5af12d0e | 1911 | put_cpu(); |
f894ffa8 | 1912 | put_online_cpus(); |
9f50fad6 | 1913 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
1914 | } |
1915 | ||
0db0628d | 1916 | static int memcg_cpu_hotplug_callback(struct notifier_block *nb, |
cdec2e42 KH |
1917 | unsigned long action, |
1918 | void *hcpu) | |
1919 | { | |
1920 | int cpu = (unsigned long)hcpu; | |
1921 | struct memcg_stock_pcp *stock; | |
1922 | ||
619d094b | 1923 | if (action == CPU_ONLINE) |
1489ebad | 1924 | return NOTIFY_OK; |
1489ebad | 1925 | |
d833049b | 1926 | if (action != CPU_DEAD && action != CPU_DEAD_FROZEN) |
cdec2e42 | 1927 | return NOTIFY_OK; |
711d3d2c | 1928 | |
cdec2e42 KH |
1929 | stock = &per_cpu(memcg_stock, cpu); |
1930 | drain_stock(stock); | |
1931 | return NOTIFY_OK; | |
1932 | } | |
1933 | ||
f7e1cb6e JW |
1934 | static void reclaim_high(struct mem_cgroup *memcg, |
1935 | unsigned int nr_pages, | |
1936 | gfp_t gfp_mask) | |
1937 | { | |
1938 | do { | |
1939 | if (page_counter_read(&memcg->memory) <= memcg->high) | |
1940 | continue; | |
1941 | mem_cgroup_events(memcg, MEMCG_HIGH, 1); | |
1942 | try_to_free_mem_cgroup_pages(memcg, nr_pages, gfp_mask, true); | |
1943 | } while ((memcg = parent_mem_cgroup(memcg))); | |
1944 | } | |
1945 | ||
1946 | static void high_work_func(struct work_struct *work) | |
1947 | { | |
1948 | struct mem_cgroup *memcg; | |
1949 | ||
1950 | memcg = container_of(work, struct mem_cgroup, high_work); | |
1951 | reclaim_high(memcg, CHARGE_BATCH, GFP_KERNEL); | |
1952 | } | |
1953 | ||
b23afb93 TH |
1954 | /* |
1955 | * Scheduled by try_charge() to be executed from the userland return path | |
1956 | * and reclaims memory over the high limit. | |
1957 | */ | |
1958 | void mem_cgroup_handle_over_high(void) | |
1959 | { | |
1960 | unsigned int nr_pages = current->memcg_nr_pages_over_high; | |
f7e1cb6e | 1961 | struct mem_cgroup *memcg; |
b23afb93 TH |
1962 | |
1963 | if (likely(!nr_pages)) | |
1964 | return; | |
1965 | ||
f7e1cb6e JW |
1966 | memcg = get_mem_cgroup_from_mm(current->mm); |
1967 | reclaim_high(memcg, nr_pages, GFP_KERNEL); | |
b23afb93 TH |
1968 | css_put(&memcg->css); |
1969 | current->memcg_nr_pages_over_high = 0; | |
1970 | } | |
1971 | ||
00501b53 JW |
1972 | static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, |
1973 | unsigned int nr_pages) | |
8a9f3ccd | 1974 | { |
7ec99d62 | 1975 | unsigned int batch = max(CHARGE_BATCH, nr_pages); |
9b130619 | 1976 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; |
6539cc05 | 1977 | struct mem_cgroup *mem_over_limit; |
3e32cb2e | 1978 | struct page_counter *counter; |
6539cc05 | 1979 | unsigned long nr_reclaimed; |
b70a2a21 JW |
1980 | bool may_swap = true; |
1981 | bool drained = false; | |
a636b327 | 1982 | |
ce00a967 | 1983 | if (mem_cgroup_is_root(memcg)) |
10d53c74 | 1984 | return 0; |
6539cc05 | 1985 | retry: |
b6b6cc72 | 1986 | if (consume_stock(memcg, nr_pages)) |
10d53c74 | 1987 | return 0; |
8a9f3ccd | 1988 | |
7941d214 | 1989 | if (!do_memsw_account() || |
6071ca52 JW |
1990 | page_counter_try_charge(&memcg->memsw, batch, &counter)) { |
1991 | if (page_counter_try_charge(&memcg->memory, batch, &counter)) | |
6539cc05 | 1992 | goto done_restock; |
7941d214 | 1993 | if (do_memsw_account()) |
3e32cb2e JW |
1994 | page_counter_uncharge(&memcg->memsw, batch); |
1995 | mem_over_limit = mem_cgroup_from_counter(counter, memory); | |
3fbe7244 | 1996 | } else { |
3e32cb2e | 1997 | mem_over_limit = mem_cgroup_from_counter(counter, memsw); |
b70a2a21 | 1998 | may_swap = false; |
3fbe7244 | 1999 | } |
7a81b88c | 2000 | |
6539cc05 JW |
2001 | if (batch > nr_pages) { |
2002 | batch = nr_pages; | |
2003 | goto retry; | |
2004 | } | |
6d61ef40 | 2005 | |
06b078fc JW |
2006 | /* |
2007 | * Unlike in global OOM situations, memcg is not in a physical | |
2008 | * memory shortage. Allow dying and OOM-killed tasks to | |
2009 | * bypass the last charges so that they can exit quickly and | |
2010 | * free their memory. | |
2011 | */ | |
2012 | if (unlikely(test_thread_flag(TIF_MEMDIE) || | |
2013 | fatal_signal_pending(current) || | |
2014 | current->flags & PF_EXITING)) | |
10d53c74 | 2015 | goto force; |
06b078fc JW |
2016 | |
2017 | if (unlikely(task_in_memcg_oom(current))) | |
2018 | goto nomem; | |
2019 | ||
d0164adc | 2020 | if (!gfpflags_allow_blocking(gfp_mask)) |
6539cc05 | 2021 | goto nomem; |
4b534334 | 2022 | |
241994ed JW |
2023 | mem_cgroup_events(mem_over_limit, MEMCG_MAX, 1); |
2024 | ||
b70a2a21 JW |
2025 | nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages, |
2026 | gfp_mask, may_swap); | |
6539cc05 | 2027 | |
61e02c74 | 2028 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
6539cc05 | 2029 | goto retry; |
28c34c29 | 2030 | |
b70a2a21 | 2031 | if (!drained) { |
6d3d6aa2 | 2032 | drain_all_stock(mem_over_limit); |
b70a2a21 JW |
2033 | drained = true; |
2034 | goto retry; | |
2035 | } | |
2036 | ||
28c34c29 JW |
2037 | if (gfp_mask & __GFP_NORETRY) |
2038 | goto nomem; | |
6539cc05 JW |
2039 | /* |
2040 | * Even though the limit is exceeded at this point, reclaim | |
2041 | * may have been able to free some pages. Retry the charge | |
2042 | * before killing the task. | |
2043 | * | |
2044 | * Only for regular pages, though: huge pages are rather | |
2045 | * unlikely to succeed so close to the limit, and we fall back | |
2046 | * to regular pages anyway in case of failure. | |
2047 | */ | |
61e02c74 | 2048 | if (nr_reclaimed && nr_pages <= (1 << PAGE_ALLOC_COSTLY_ORDER)) |
6539cc05 JW |
2049 | goto retry; |
2050 | /* | |
2051 | * At task move, charge accounts can be doubly counted. So, it's | |
2052 | * better to wait until the end of task_move if something is going on. | |
2053 | */ | |
2054 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2055 | goto retry; | |
2056 | ||
9b130619 JW |
2057 | if (nr_retries--) |
2058 | goto retry; | |
2059 | ||
06b078fc | 2060 | if (gfp_mask & __GFP_NOFAIL) |
10d53c74 | 2061 | goto force; |
06b078fc | 2062 | |
6539cc05 | 2063 | if (fatal_signal_pending(current)) |
10d53c74 | 2064 | goto force; |
6539cc05 | 2065 | |
241994ed JW |
2066 | mem_cgroup_events(mem_over_limit, MEMCG_OOM, 1); |
2067 | ||
3608de07 JM |
2068 | mem_cgroup_oom(mem_over_limit, gfp_mask, |
2069 | get_order(nr_pages * PAGE_SIZE)); | |
7a81b88c | 2070 | nomem: |
6d1fdc48 | 2071 | if (!(gfp_mask & __GFP_NOFAIL)) |
3168ecbe | 2072 | return -ENOMEM; |
10d53c74 TH |
2073 | force: |
2074 | /* | |
2075 | * The allocation either can't fail or will lead to more memory | |
2076 | * being freed very soon. Allow memory usage go over the limit | |
2077 | * temporarily by force charging it. | |
2078 | */ | |
2079 | page_counter_charge(&memcg->memory, nr_pages); | |
7941d214 | 2080 | if (do_memsw_account()) |
10d53c74 TH |
2081 | page_counter_charge(&memcg->memsw, nr_pages); |
2082 | css_get_many(&memcg->css, nr_pages); | |
2083 | ||
2084 | return 0; | |
6539cc05 JW |
2085 | |
2086 | done_restock: | |
e8ea14cc | 2087 | css_get_many(&memcg->css, batch); |
6539cc05 JW |
2088 | if (batch > nr_pages) |
2089 | refill_stock(memcg, batch - nr_pages); | |
b23afb93 | 2090 | |
241994ed | 2091 | /* |
b23afb93 TH |
2092 | * If the hierarchy is above the normal consumption range, schedule |
2093 | * reclaim on returning to userland. We can perform reclaim here | |
71baba4b | 2094 | * if __GFP_RECLAIM but let's always punt for simplicity and so that |
b23afb93 TH |
2095 | * GFP_KERNEL can consistently be used during reclaim. @memcg is |
2096 | * not recorded as it most likely matches current's and won't | |
2097 | * change in the meantime. As high limit is checked again before | |
2098 | * reclaim, the cost of mismatch is negligible. | |
241994ed JW |
2099 | */ |
2100 | do { | |
b23afb93 | 2101 | if (page_counter_read(&memcg->memory) > memcg->high) { |
f7e1cb6e JW |
2102 | /* Don't bother a random interrupted task */ |
2103 | if (in_interrupt()) { | |
2104 | schedule_work(&memcg->high_work); | |
2105 | break; | |
2106 | } | |
9516a18a | 2107 | current->memcg_nr_pages_over_high += batch; |
b23afb93 TH |
2108 | set_notify_resume(current); |
2109 | break; | |
2110 | } | |
241994ed | 2111 | } while ((memcg = parent_mem_cgroup(memcg))); |
10d53c74 TH |
2112 | |
2113 | return 0; | |
7a81b88c | 2114 | } |
8a9f3ccd | 2115 | |
00501b53 | 2116 | static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) |
a3032a2c | 2117 | { |
ce00a967 JW |
2118 | if (mem_cgroup_is_root(memcg)) |
2119 | return; | |
2120 | ||
3e32cb2e | 2121 | page_counter_uncharge(&memcg->memory, nr_pages); |
7941d214 | 2122 | if (do_memsw_account()) |
3e32cb2e | 2123 | page_counter_uncharge(&memcg->memsw, nr_pages); |
ce00a967 | 2124 | |
e8ea14cc | 2125 | css_put_many(&memcg->css, nr_pages); |
d01dd17f KH |
2126 | } |
2127 | ||
0a31bc97 JW |
2128 | static void lock_page_lru(struct page *page, int *isolated) |
2129 | { | |
2130 | struct zone *zone = page_zone(page); | |
2131 | ||
2132 | spin_lock_irq(&zone->lru_lock); | |
2133 | if (PageLRU(page)) { | |
2134 | struct lruvec *lruvec; | |
2135 | ||
2136 | lruvec = mem_cgroup_page_lruvec(page, zone); | |
2137 | ClearPageLRU(page); | |
2138 | del_page_from_lru_list(page, lruvec, page_lru(page)); | |
2139 | *isolated = 1; | |
2140 | } else | |
2141 | *isolated = 0; | |
2142 | } | |
2143 | ||
2144 | static void unlock_page_lru(struct page *page, int isolated) | |
2145 | { | |
2146 | struct zone *zone = page_zone(page); | |
2147 | ||
2148 | if (isolated) { | |
2149 | struct lruvec *lruvec; | |
2150 | ||
2151 | lruvec = mem_cgroup_page_lruvec(page, zone); | |
2152 | VM_BUG_ON_PAGE(PageLRU(page), page); | |
2153 | SetPageLRU(page); | |
2154 | add_page_to_lru_list(page, lruvec, page_lru(page)); | |
2155 | } | |
2156 | spin_unlock_irq(&zone->lru_lock); | |
2157 | } | |
2158 | ||
00501b53 | 2159 | static void commit_charge(struct page *page, struct mem_cgroup *memcg, |
6abb5a86 | 2160 | bool lrucare) |
7a81b88c | 2161 | { |
0a31bc97 | 2162 | int isolated; |
9ce70c02 | 2163 | |
1306a85a | 2164 | VM_BUG_ON_PAGE(page->mem_cgroup, page); |
9ce70c02 HD |
2165 | |
2166 | /* | |
2167 | * In some cases, SwapCache and FUSE(splice_buf->radixtree), the page | |
2168 | * may already be on some other mem_cgroup's LRU. Take care of it. | |
2169 | */ | |
0a31bc97 JW |
2170 | if (lrucare) |
2171 | lock_page_lru(page, &isolated); | |
9ce70c02 | 2172 | |
0a31bc97 JW |
2173 | /* |
2174 | * Nobody should be changing or seriously looking at | |
1306a85a | 2175 | * page->mem_cgroup at this point: |
0a31bc97 JW |
2176 | * |
2177 | * - the page is uncharged | |
2178 | * | |
2179 | * - the page is off-LRU | |
2180 | * | |
2181 | * - an anonymous fault has exclusive page access, except for | |
2182 | * a locked page table | |
2183 | * | |
2184 | * - a page cache insertion, a swapin fault, or a migration | |
2185 | * have the page locked | |
2186 | */ | |
1306a85a | 2187 | page->mem_cgroup = memcg; |
9ce70c02 | 2188 | |
0a31bc97 JW |
2189 | if (lrucare) |
2190 | unlock_page_lru(page, isolated); | |
7a81b88c | 2191 | } |
66e1707b | 2192 | |
127424c8 | 2193 | #ifndef CONFIG_SLOB |
f3bb3043 | 2194 | static int memcg_alloc_cache_id(void) |
55007d84 | 2195 | { |
f3bb3043 VD |
2196 | int id, size; |
2197 | int err; | |
2198 | ||
dbcf73e2 | 2199 | id = ida_simple_get(&memcg_cache_ida, |
f3bb3043 VD |
2200 | 0, MEMCG_CACHES_MAX_SIZE, GFP_KERNEL); |
2201 | if (id < 0) | |
2202 | return id; | |
55007d84 | 2203 | |
dbcf73e2 | 2204 | if (id < memcg_nr_cache_ids) |
f3bb3043 VD |
2205 | return id; |
2206 | ||
2207 | /* | |
2208 | * There's no space for the new id in memcg_caches arrays, | |
2209 | * so we have to grow them. | |
2210 | */ | |
05257a1a | 2211 | down_write(&memcg_cache_ids_sem); |
f3bb3043 VD |
2212 | |
2213 | size = 2 * (id + 1); | |
55007d84 GC |
2214 | if (size < MEMCG_CACHES_MIN_SIZE) |
2215 | size = MEMCG_CACHES_MIN_SIZE; | |
2216 | else if (size > MEMCG_CACHES_MAX_SIZE) | |
2217 | size = MEMCG_CACHES_MAX_SIZE; | |
2218 | ||
f3bb3043 | 2219 | err = memcg_update_all_caches(size); |
60d3fd32 VD |
2220 | if (!err) |
2221 | err = memcg_update_all_list_lrus(size); | |
05257a1a VD |
2222 | if (!err) |
2223 | memcg_nr_cache_ids = size; | |
2224 | ||
2225 | up_write(&memcg_cache_ids_sem); | |
2226 | ||
f3bb3043 | 2227 | if (err) { |
dbcf73e2 | 2228 | ida_simple_remove(&memcg_cache_ida, id); |
f3bb3043 VD |
2229 | return err; |
2230 | } | |
2231 | return id; | |
2232 | } | |
2233 | ||
2234 | static void memcg_free_cache_id(int id) | |
2235 | { | |
dbcf73e2 | 2236 | ida_simple_remove(&memcg_cache_ida, id); |
55007d84 GC |
2237 | } |
2238 | ||
d5b3cf71 | 2239 | struct memcg_kmem_cache_create_work { |
5722d094 VD |
2240 | struct mem_cgroup *memcg; |
2241 | struct kmem_cache *cachep; | |
2242 | struct work_struct work; | |
2243 | }; | |
2244 | ||
d5b3cf71 | 2245 | static void memcg_kmem_cache_create_func(struct work_struct *w) |
d7f25f8a | 2246 | { |
d5b3cf71 VD |
2247 | struct memcg_kmem_cache_create_work *cw = |
2248 | container_of(w, struct memcg_kmem_cache_create_work, work); | |
5722d094 VD |
2249 | struct mem_cgroup *memcg = cw->memcg; |
2250 | struct kmem_cache *cachep = cw->cachep; | |
d7f25f8a | 2251 | |
d5b3cf71 | 2252 | memcg_create_kmem_cache(memcg, cachep); |
bd673145 | 2253 | |
5722d094 | 2254 | css_put(&memcg->css); |
d7f25f8a GC |
2255 | kfree(cw); |
2256 | } | |
2257 | ||
2258 | /* | |
2259 | * Enqueue the creation of a per-memcg kmem_cache. | |
d7f25f8a | 2260 | */ |
d5b3cf71 VD |
2261 | static void __memcg_schedule_kmem_cache_create(struct mem_cgroup *memcg, |
2262 | struct kmem_cache *cachep) | |
d7f25f8a | 2263 | { |
d5b3cf71 | 2264 | struct memcg_kmem_cache_create_work *cw; |
d7f25f8a | 2265 | |
776ed0f0 | 2266 | cw = kmalloc(sizeof(*cw), GFP_NOWAIT); |
8135be5a | 2267 | if (!cw) |
d7f25f8a | 2268 | return; |
8135be5a VD |
2269 | |
2270 | css_get(&memcg->css); | |
d7f25f8a GC |
2271 | |
2272 | cw->memcg = memcg; | |
2273 | cw->cachep = cachep; | |
d5b3cf71 | 2274 | INIT_WORK(&cw->work, memcg_kmem_cache_create_func); |
d7f25f8a | 2275 | |
d7f25f8a GC |
2276 | schedule_work(&cw->work); |
2277 | } | |
2278 | ||
d5b3cf71 VD |
2279 | static void memcg_schedule_kmem_cache_create(struct mem_cgroup *memcg, |
2280 | struct kmem_cache *cachep) | |
0e9d92f2 GC |
2281 | { |
2282 | /* | |
2283 | * We need to stop accounting when we kmalloc, because if the | |
2284 | * corresponding kmalloc cache is not yet created, the first allocation | |
d5b3cf71 | 2285 | * in __memcg_schedule_kmem_cache_create will recurse. |
0e9d92f2 GC |
2286 | * |
2287 | * However, it is better to enclose the whole function. Depending on | |
2288 | * the debugging options enabled, INIT_WORK(), for instance, can | |
2289 | * trigger an allocation. This too, will make us recurse. Because at | |
2290 | * this point we can't allow ourselves back into memcg_kmem_get_cache, | |
2291 | * the safest choice is to do it like this, wrapping the whole function. | |
2292 | */ | |
6f185c29 | 2293 | current->memcg_kmem_skip_account = 1; |
d5b3cf71 | 2294 | __memcg_schedule_kmem_cache_create(memcg, cachep); |
6f185c29 | 2295 | current->memcg_kmem_skip_account = 0; |
0e9d92f2 | 2296 | } |
c67a8a68 | 2297 | |
d7f25f8a GC |
2298 | /* |
2299 | * Return the kmem_cache we're supposed to use for a slab allocation. | |
2300 | * We try to use the current memcg's version of the cache. | |
2301 | * | |
2302 | * If the cache does not exist yet, if we are the first user of it, | |
2303 | * we either create it immediately, if possible, or create it asynchronously | |
2304 | * in a workqueue. | |
2305 | * In the latter case, we will let the current allocation go through with | |
2306 | * the original cache. | |
2307 | * | |
2308 | * Can't be called in interrupt context or from kernel threads. | |
2309 | * This function needs to be called with rcu_read_lock() held. | |
2310 | */ | |
230e9fc2 | 2311 | struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp) |
d7f25f8a GC |
2312 | { |
2313 | struct mem_cgroup *memcg; | |
959c8963 | 2314 | struct kmem_cache *memcg_cachep; |
2a4db7eb | 2315 | int kmemcg_id; |
d7f25f8a | 2316 | |
f7ce3190 | 2317 | VM_BUG_ON(!is_root_cache(cachep)); |
d7f25f8a | 2318 | |
230e9fc2 VD |
2319 | if (cachep->flags & SLAB_ACCOUNT) |
2320 | gfp |= __GFP_ACCOUNT; | |
2321 | ||
2322 | if (!(gfp & __GFP_ACCOUNT)) | |
2323 | return cachep; | |
2324 | ||
9d100c5e | 2325 | if (current->memcg_kmem_skip_account) |
0e9d92f2 GC |
2326 | return cachep; |
2327 | ||
8135be5a | 2328 | memcg = get_mem_cgroup_from_mm(current->mm); |
4db0c3c2 | 2329 | kmemcg_id = READ_ONCE(memcg->kmemcg_id); |
2a4db7eb | 2330 | if (kmemcg_id < 0) |
ca0dde97 | 2331 | goto out; |
d7f25f8a | 2332 | |
2a4db7eb | 2333 | memcg_cachep = cache_from_memcg_idx(cachep, kmemcg_id); |
8135be5a VD |
2334 | if (likely(memcg_cachep)) |
2335 | return memcg_cachep; | |
ca0dde97 LZ |
2336 | |
2337 | /* | |
2338 | * If we are in a safe context (can wait, and not in interrupt | |
2339 | * context), we could be be predictable and return right away. | |
2340 | * This would guarantee that the allocation being performed | |
2341 | * already belongs in the new cache. | |
2342 | * | |
2343 | * However, there are some clashes that can arrive from locking. | |
2344 | * For instance, because we acquire the slab_mutex while doing | |
776ed0f0 VD |
2345 | * memcg_create_kmem_cache, this means no further allocation |
2346 | * could happen with the slab_mutex held. So it's better to | |
2347 | * defer everything. | |
ca0dde97 | 2348 | */ |
d5b3cf71 | 2349 | memcg_schedule_kmem_cache_create(memcg, cachep); |
ca0dde97 | 2350 | out: |
8135be5a | 2351 | css_put(&memcg->css); |
ca0dde97 | 2352 | return cachep; |
d7f25f8a | 2353 | } |
d7f25f8a | 2354 | |
8135be5a VD |
2355 | void __memcg_kmem_put_cache(struct kmem_cache *cachep) |
2356 | { | |
2357 | if (!is_root_cache(cachep)) | |
f7ce3190 | 2358 | css_put(&cachep->memcg_params.memcg->css); |
8135be5a VD |
2359 | } |
2360 | ||
f3ccb2c4 VD |
2361 | int __memcg_kmem_charge_memcg(struct page *page, gfp_t gfp, int order, |
2362 | struct mem_cgroup *memcg) | |
7ae1e1d0 | 2363 | { |
f3ccb2c4 VD |
2364 | unsigned int nr_pages = 1 << order; |
2365 | struct page_counter *counter; | |
7ae1e1d0 GC |
2366 | int ret; |
2367 | ||
567e9ab2 | 2368 | if (!memcg_kmem_online(memcg)) |
d05e83a6 | 2369 | return 0; |
6d42c232 | 2370 | |
f3ccb2c4 | 2371 | ret = try_charge(memcg, gfp, nr_pages); |
52c29b04 | 2372 | if (ret) |
f3ccb2c4 | 2373 | return ret; |
52c29b04 JW |
2374 | |
2375 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && | |
2376 | !page_counter_try_charge(&memcg->kmem, nr_pages, &counter)) { | |
2377 | cancel_charge(memcg, nr_pages); | |
2378 | return -ENOMEM; | |
7ae1e1d0 GC |
2379 | } |
2380 | ||
f3ccb2c4 | 2381 | page->mem_cgroup = memcg; |
7ae1e1d0 | 2382 | |
f3ccb2c4 | 2383 | return 0; |
7ae1e1d0 GC |
2384 | } |
2385 | ||
f3ccb2c4 | 2386 | int __memcg_kmem_charge(struct page *page, gfp_t gfp, int order) |
7ae1e1d0 | 2387 | { |
f3ccb2c4 VD |
2388 | struct mem_cgroup *memcg; |
2389 | int ret; | |
7ae1e1d0 | 2390 | |
f3ccb2c4 VD |
2391 | memcg = get_mem_cgroup_from_mm(current->mm); |
2392 | ret = __memcg_kmem_charge_memcg(page, gfp, order, memcg); | |
7ae1e1d0 | 2393 | css_put(&memcg->css); |
d05e83a6 | 2394 | return ret; |
7ae1e1d0 GC |
2395 | } |
2396 | ||
d05e83a6 | 2397 | void __memcg_kmem_uncharge(struct page *page, int order) |
7ae1e1d0 | 2398 | { |
1306a85a | 2399 | struct mem_cgroup *memcg = page->mem_cgroup; |
f3ccb2c4 | 2400 | unsigned int nr_pages = 1 << order; |
7ae1e1d0 | 2401 | |
7ae1e1d0 GC |
2402 | if (!memcg) |
2403 | return; | |
2404 | ||
309381fe | 2405 | VM_BUG_ON_PAGE(mem_cgroup_is_root(memcg), page); |
29833315 | 2406 | |
52c29b04 JW |
2407 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
2408 | page_counter_uncharge(&memcg->kmem, nr_pages); | |
2409 | ||
f3ccb2c4 | 2410 | page_counter_uncharge(&memcg->memory, nr_pages); |
7941d214 | 2411 | if (do_memsw_account()) |
f3ccb2c4 | 2412 | page_counter_uncharge(&memcg->memsw, nr_pages); |
60d3fd32 | 2413 | |
1306a85a | 2414 | page->mem_cgroup = NULL; |
f3ccb2c4 | 2415 | css_put_many(&memcg->css, nr_pages); |
60d3fd32 | 2416 | } |
127424c8 | 2417 | #endif /* !CONFIG_SLOB */ |
7ae1e1d0 | 2418 | |
ca3e0214 KH |
2419 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
2420 | ||
ca3e0214 KH |
2421 | /* |
2422 | * Because tail pages are not marked as "used", set it. We're under | |
3ac808fd | 2423 | * zone->lru_lock and migration entries setup in all page mappings. |
ca3e0214 | 2424 | */ |
e94c8a9c | 2425 | void mem_cgroup_split_huge_fixup(struct page *head) |
ca3e0214 | 2426 | { |
e94c8a9c | 2427 | int i; |
ca3e0214 | 2428 | |
3d37c4a9 KH |
2429 | if (mem_cgroup_disabled()) |
2430 | return; | |
b070e65c | 2431 | |
29833315 | 2432 | for (i = 1; i < HPAGE_PMD_NR; i++) |
1306a85a | 2433 | head[i].mem_cgroup = head->mem_cgroup; |
b9982f8d | 2434 | |
1306a85a | 2435 | __this_cpu_sub(head->mem_cgroup->stat->count[MEM_CGROUP_STAT_RSS_HUGE], |
b070e65c | 2436 | HPAGE_PMD_NR); |
ca3e0214 | 2437 | } |
12d27107 | 2438 | #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
ca3e0214 | 2439 | |
c255a458 | 2440 | #ifdef CONFIG_MEMCG_SWAP |
0a31bc97 JW |
2441 | static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg, |
2442 | bool charge) | |
d13d1443 | 2443 | { |
0a31bc97 JW |
2444 | int val = (charge) ? 1 : -1; |
2445 | this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_SWAP], val); | |
d13d1443 | 2446 | } |
02491447 DN |
2447 | |
2448 | /** | |
2449 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
2450 | * @entry: swap entry to be moved | |
2451 | * @from: mem_cgroup which the entry is moved from | |
2452 | * @to: mem_cgroup which the entry is moved to | |
2453 | * | |
2454 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
2455 | * as the mem_cgroup's id of @from. | |
2456 | * | |
2457 | * Returns 0 on success, -EINVAL on failure. | |
2458 | * | |
3e32cb2e | 2459 | * The caller must have charged to @to, IOW, called page_counter_charge() about |
02491447 DN |
2460 | * both res and memsw, and called css_get(). |
2461 | */ | |
2462 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 2463 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
2464 | { |
2465 | unsigned short old_id, new_id; | |
2466 | ||
34c00c31 LZ |
2467 | old_id = mem_cgroup_id(from); |
2468 | new_id = mem_cgroup_id(to); | |
02491447 DN |
2469 | |
2470 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
02491447 | 2471 | mem_cgroup_swap_statistics(from, false); |
483c30b5 | 2472 | mem_cgroup_swap_statistics(to, true); |
02491447 DN |
2473 | return 0; |
2474 | } | |
2475 | return -EINVAL; | |
2476 | } | |
2477 | #else | |
2478 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 2479 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
2480 | { |
2481 | return -EINVAL; | |
2482 | } | |
8c7c6e34 | 2483 | #endif |
d13d1443 | 2484 | |
3e32cb2e | 2485 | static DEFINE_MUTEX(memcg_limit_mutex); |
f212ad7c | 2486 | |
d38d2a75 | 2487 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
3e32cb2e | 2488 | unsigned long limit) |
628f4235 | 2489 | { |
3e32cb2e JW |
2490 | unsigned long curusage; |
2491 | unsigned long oldusage; | |
2492 | bool enlarge = false; | |
81d39c20 | 2493 | int retry_count; |
3e32cb2e | 2494 | int ret; |
81d39c20 KH |
2495 | |
2496 | /* | |
2497 | * For keeping hierarchical_reclaim simple, how long we should retry | |
2498 | * is depends on callers. We set our retry-count to be function | |
2499 | * of # of children which we should visit in this loop. | |
2500 | */ | |
3e32cb2e JW |
2501 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * |
2502 | mem_cgroup_count_children(memcg); | |
81d39c20 | 2503 | |
3e32cb2e | 2504 | oldusage = page_counter_read(&memcg->memory); |
628f4235 | 2505 | |
3e32cb2e | 2506 | do { |
628f4235 KH |
2507 | if (signal_pending(current)) { |
2508 | ret = -EINTR; | |
2509 | break; | |
2510 | } | |
3e32cb2e JW |
2511 | |
2512 | mutex_lock(&memcg_limit_mutex); | |
2513 | if (limit > memcg->memsw.limit) { | |
2514 | mutex_unlock(&memcg_limit_mutex); | |
8c7c6e34 | 2515 | ret = -EINVAL; |
628f4235 KH |
2516 | break; |
2517 | } | |
3e32cb2e JW |
2518 | if (limit > memcg->memory.limit) |
2519 | enlarge = true; | |
2520 | ret = page_counter_limit(&memcg->memory, limit); | |
2521 | mutex_unlock(&memcg_limit_mutex); | |
8c7c6e34 KH |
2522 | |
2523 | if (!ret) | |
2524 | break; | |
2525 | ||
b70a2a21 JW |
2526 | try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, true); |
2527 | ||
3e32cb2e | 2528 | curusage = page_counter_read(&memcg->memory); |
81d39c20 | 2529 | /* Usage is reduced ? */ |
f894ffa8 | 2530 | if (curusage >= oldusage) |
81d39c20 KH |
2531 | retry_count--; |
2532 | else | |
2533 | oldusage = curusage; | |
3e32cb2e JW |
2534 | } while (retry_count); |
2535 | ||
3c11ecf4 KH |
2536 | if (!ret && enlarge) |
2537 | memcg_oom_recover(memcg); | |
14797e23 | 2538 | |
8c7c6e34 KH |
2539 | return ret; |
2540 | } | |
2541 | ||
338c8431 | 2542 | static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, |
3e32cb2e | 2543 | unsigned long limit) |
8c7c6e34 | 2544 | { |
3e32cb2e JW |
2545 | unsigned long curusage; |
2546 | unsigned long oldusage; | |
2547 | bool enlarge = false; | |
81d39c20 | 2548 | int retry_count; |
3e32cb2e | 2549 | int ret; |
8c7c6e34 | 2550 | |
81d39c20 | 2551 | /* see mem_cgroup_resize_res_limit */ |
3e32cb2e JW |
2552 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * |
2553 | mem_cgroup_count_children(memcg); | |
2554 | ||
2555 | oldusage = page_counter_read(&memcg->memsw); | |
2556 | ||
2557 | do { | |
8c7c6e34 KH |
2558 | if (signal_pending(current)) { |
2559 | ret = -EINTR; | |
2560 | break; | |
2561 | } | |
3e32cb2e JW |
2562 | |
2563 | mutex_lock(&memcg_limit_mutex); | |
2564 | if (limit < memcg->memory.limit) { | |
2565 | mutex_unlock(&memcg_limit_mutex); | |
8c7c6e34 | 2566 | ret = -EINVAL; |
8c7c6e34 KH |
2567 | break; |
2568 | } | |
3e32cb2e JW |
2569 | if (limit > memcg->memsw.limit) |
2570 | enlarge = true; | |
2571 | ret = page_counter_limit(&memcg->memsw, limit); | |
2572 | mutex_unlock(&memcg_limit_mutex); | |
8c7c6e34 KH |
2573 | |
2574 | if (!ret) | |
2575 | break; | |
2576 | ||
b70a2a21 JW |
2577 | try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, false); |
2578 | ||
3e32cb2e | 2579 | curusage = page_counter_read(&memcg->memsw); |
81d39c20 | 2580 | /* Usage is reduced ? */ |
8c7c6e34 | 2581 | if (curusage >= oldusage) |
628f4235 | 2582 | retry_count--; |
81d39c20 KH |
2583 | else |
2584 | oldusage = curusage; | |
3e32cb2e JW |
2585 | } while (retry_count); |
2586 | ||
3c11ecf4 KH |
2587 | if (!ret && enlarge) |
2588 | memcg_oom_recover(memcg); | |
3e32cb2e | 2589 | |
628f4235 KH |
2590 | return ret; |
2591 | } | |
2592 | ||
0608f43d AM |
2593 | unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, |
2594 | gfp_t gfp_mask, | |
2595 | unsigned long *total_scanned) | |
2596 | { | |
2597 | unsigned long nr_reclaimed = 0; | |
2598 | struct mem_cgroup_per_zone *mz, *next_mz = NULL; | |
2599 | unsigned long reclaimed; | |
2600 | int loop = 0; | |
2601 | struct mem_cgroup_tree_per_zone *mctz; | |
3e32cb2e | 2602 | unsigned long excess; |
0608f43d AM |
2603 | unsigned long nr_scanned; |
2604 | ||
2605 | if (order > 0) | |
2606 | return 0; | |
2607 | ||
2608 | mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone)); | |
2609 | /* | |
2610 | * This loop can run a while, specially if mem_cgroup's continuously | |
2611 | * keep exceeding their soft limit and putting the system under | |
2612 | * pressure | |
2613 | */ | |
2614 | do { | |
2615 | if (next_mz) | |
2616 | mz = next_mz; | |
2617 | else | |
2618 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
2619 | if (!mz) | |
2620 | break; | |
2621 | ||
2622 | nr_scanned = 0; | |
2623 | reclaimed = mem_cgroup_soft_reclaim(mz->memcg, zone, | |
2624 | gfp_mask, &nr_scanned); | |
2625 | nr_reclaimed += reclaimed; | |
2626 | *total_scanned += nr_scanned; | |
0a31bc97 | 2627 | spin_lock_irq(&mctz->lock); |
bc2f2e7f | 2628 | __mem_cgroup_remove_exceeded(mz, mctz); |
0608f43d AM |
2629 | |
2630 | /* | |
2631 | * If we failed to reclaim anything from this memory cgroup | |
2632 | * it is time to move on to the next cgroup | |
2633 | */ | |
2634 | next_mz = NULL; | |
bc2f2e7f VD |
2635 | if (!reclaimed) |
2636 | next_mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
2637 | ||
3e32cb2e | 2638 | excess = soft_limit_excess(mz->memcg); |
0608f43d AM |
2639 | /* |
2640 | * One school of thought says that we should not add | |
2641 | * back the node to the tree if reclaim returns 0. | |
2642 | * But our reclaim could return 0, simply because due | |
2643 | * to priority we are exposing a smaller subset of | |
2644 | * memory to reclaim from. Consider this as a longer | |
2645 | * term TODO. | |
2646 | */ | |
2647 | /* If excess == 0, no tree ops */ | |
cf2c8127 | 2648 | __mem_cgroup_insert_exceeded(mz, mctz, excess); |
0a31bc97 | 2649 | spin_unlock_irq(&mctz->lock); |
0608f43d AM |
2650 | css_put(&mz->memcg->css); |
2651 | loop++; | |
2652 | /* | |
2653 | * Could not reclaim anything and there are no more | |
2654 | * mem cgroups to try or we seem to be looping without | |
2655 | * reclaiming anything. | |
2656 | */ | |
2657 | if (!nr_reclaimed && | |
2658 | (next_mz == NULL || | |
2659 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
2660 | break; | |
2661 | } while (!nr_reclaimed); | |
2662 | if (next_mz) | |
2663 | css_put(&next_mz->memcg->css); | |
2664 | return nr_reclaimed; | |
2665 | } | |
2666 | ||
ea280e7b TH |
2667 | /* |
2668 | * Test whether @memcg has children, dead or alive. Note that this | |
2669 | * function doesn't care whether @memcg has use_hierarchy enabled and | |
2670 | * returns %true if there are child csses according to the cgroup | |
2671 | * hierarchy. Testing use_hierarchy is the caller's responsiblity. | |
2672 | */ | |
b5f99b53 GC |
2673 | static inline bool memcg_has_children(struct mem_cgroup *memcg) |
2674 | { | |
ea280e7b TH |
2675 | bool ret; |
2676 | ||
ea280e7b TH |
2677 | rcu_read_lock(); |
2678 | ret = css_next_child(NULL, &memcg->css); | |
2679 | rcu_read_unlock(); | |
2680 | return ret; | |
b5f99b53 GC |
2681 | } |
2682 | ||
c26251f9 MH |
2683 | /* |
2684 | * Reclaims as many pages from the given memcg as possible and moves | |
2685 | * the rest to the parent. | |
2686 | * | |
2687 | * Caller is responsible for holding css reference for memcg. | |
2688 | */ | |
2689 | static int mem_cgroup_force_empty(struct mem_cgroup *memcg) | |
2690 | { | |
2691 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
c26251f9 | 2692 | |
c1e862c1 KH |
2693 | /* we call try-to-free pages for make this cgroup empty */ |
2694 | lru_add_drain_all(); | |
f817ed48 | 2695 | /* try to free all pages in this cgroup */ |
3e32cb2e | 2696 | while (nr_retries && page_counter_read(&memcg->memory)) { |
f817ed48 | 2697 | int progress; |
c1e862c1 | 2698 | |
c26251f9 MH |
2699 | if (signal_pending(current)) |
2700 | return -EINTR; | |
2701 | ||
b70a2a21 JW |
2702 | progress = try_to_free_mem_cgroup_pages(memcg, 1, |
2703 | GFP_KERNEL, true); | |
c1e862c1 | 2704 | if (!progress) { |
f817ed48 | 2705 | nr_retries--; |
c1e862c1 | 2706 | /* maybe some writeback is necessary */ |
8aa7e847 | 2707 | congestion_wait(BLK_RW_ASYNC, HZ/10); |
c1e862c1 | 2708 | } |
f817ed48 KH |
2709 | |
2710 | } | |
ab5196c2 MH |
2711 | |
2712 | return 0; | |
cc847582 KH |
2713 | } |
2714 | ||
6770c64e TH |
2715 | static ssize_t mem_cgroup_force_empty_write(struct kernfs_open_file *of, |
2716 | char *buf, size_t nbytes, | |
2717 | loff_t off) | |
c1e862c1 | 2718 | { |
6770c64e | 2719 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
c26251f9 | 2720 | |
d8423011 MH |
2721 | if (mem_cgroup_is_root(memcg)) |
2722 | return -EINVAL; | |
6770c64e | 2723 | return mem_cgroup_force_empty(memcg) ?: nbytes; |
c1e862c1 KH |
2724 | } |
2725 | ||
182446d0 TH |
2726 | static u64 mem_cgroup_hierarchy_read(struct cgroup_subsys_state *css, |
2727 | struct cftype *cft) | |
18f59ea7 | 2728 | { |
182446d0 | 2729 | return mem_cgroup_from_css(css)->use_hierarchy; |
18f59ea7 BS |
2730 | } |
2731 | ||
182446d0 TH |
2732 | static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css, |
2733 | struct cftype *cft, u64 val) | |
18f59ea7 BS |
2734 | { |
2735 | int retval = 0; | |
182446d0 | 2736 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
5c9d535b | 2737 | struct mem_cgroup *parent_memcg = mem_cgroup_from_css(memcg->css.parent); |
18f59ea7 | 2738 | |
567fb435 | 2739 | if (memcg->use_hierarchy == val) |
0b8f73e1 | 2740 | return 0; |
567fb435 | 2741 | |
18f59ea7 | 2742 | /* |
af901ca1 | 2743 | * If parent's use_hierarchy is set, we can't make any modifications |
18f59ea7 BS |
2744 | * in the child subtrees. If it is unset, then the change can |
2745 | * occur, provided the current cgroup has no children. | |
2746 | * | |
2747 | * For the root cgroup, parent_mem is NULL, we allow value to be | |
2748 | * set if there are no children. | |
2749 | */ | |
c0ff4b85 | 2750 | if ((!parent_memcg || !parent_memcg->use_hierarchy) && |
18f59ea7 | 2751 | (val == 1 || val == 0)) { |
ea280e7b | 2752 | if (!memcg_has_children(memcg)) |
c0ff4b85 | 2753 | memcg->use_hierarchy = val; |
18f59ea7 BS |
2754 | else |
2755 | retval = -EBUSY; | |
2756 | } else | |
2757 | retval = -EINVAL; | |
567fb435 | 2758 | |
18f59ea7 BS |
2759 | return retval; |
2760 | } | |
2761 | ||
3e32cb2e JW |
2762 | static unsigned long tree_stat(struct mem_cgroup *memcg, |
2763 | enum mem_cgroup_stat_index idx) | |
ce00a967 JW |
2764 | { |
2765 | struct mem_cgroup *iter; | |
484ebb3b | 2766 | unsigned long val = 0; |
ce00a967 | 2767 | |
ce00a967 JW |
2768 | for_each_mem_cgroup_tree(iter, memcg) |
2769 | val += mem_cgroup_read_stat(iter, idx); | |
2770 | ||
ce00a967 JW |
2771 | return val; |
2772 | } | |
2773 | ||
6f646156 | 2774 | static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) |
ce00a967 | 2775 | { |
c12176d3 | 2776 | unsigned long val; |
ce00a967 | 2777 | |
3e32cb2e JW |
2778 | if (mem_cgroup_is_root(memcg)) { |
2779 | val = tree_stat(memcg, MEM_CGROUP_STAT_CACHE); | |
2780 | val += tree_stat(memcg, MEM_CGROUP_STAT_RSS); | |
2781 | if (swap) | |
2782 | val += tree_stat(memcg, MEM_CGROUP_STAT_SWAP); | |
2783 | } else { | |
ce00a967 | 2784 | if (!swap) |
3e32cb2e | 2785 | val = page_counter_read(&memcg->memory); |
ce00a967 | 2786 | else |
3e32cb2e | 2787 | val = page_counter_read(&memcg->memsw); |
ce00a967 | 2788 | } |
c12176d3 | 2789 | return val; |
ce00a967 JW |
2790 | } |
2791 | ||
3e32cb2e JW |
2792 | enum { |
2793 | RES_USAGE, | |
2794 | RES_LIMIT, | |
2795 | RES_MAX_USAGE, | |
2796 | RES_FAILCNT, | |
2797 | RES_SOFT_LIMIT, | |
2798 | }; | |
ce00a967 | 2799 | |
791badbd | 2800 | static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css, |
05b84301 | 2801 | struct cftype *cft) |
8cdea7c0 | 2802 | { |
182446d0 | 2803 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3e32cb2e | 2804 | struct page_counter *counter; |
af36f906 | 2805 | |
3e32cb2e | 2806 | switch (MEMFILE_TYPE(cft->private)) { |
8c7c6e34 | 2807 | case _MEM: |
3e32cb2e JW |
2808 | counter = &memcg->memory; |
2809 | break; | |
8c7c6e34 | 2810 | case _MEMSWAP: |
3e32cb2e JW |
2811 | counter = &memcg->memsw; |
2812 | break; | |
510fc4e1 | 2813 | case _KMEM: |
3e32cb2e | 2814 | counter = &memcg->kmem; |
510fc4e1 | 2815 | break; |
d55f90bf | 2816 | case _TCP: |
0db15298 | 2817 | counter = &memcg->tcpmem; |
d55f90bf | 2818 | break; |
8c7c6e34 KH |
2819 | default: |
2820 | BUG(); | |
8c7c6e34 | 2821 | } |
3e32cb2e JW |
2822 | |
2823 | switch (MEMFILE_ATTR(cft->private)) { | |
2824 | case RES_USAGE: | |
2825 | if (counter == &memcg->memory) | |
c12176d3 | 2826 | return (u64)mem_cgroup_usage(memcg, false) * PAGE_SIZE; |
3e32cb2e | 2827 | if (counter == &memcg->memsw) |
c12176d3 | 2828 | return (u64)mem_cgroup_usage(memcg, true) * PAGE_SIZE; |
3e32cb2e JW |
2829 | return (u64)page_counter_read(counter) * PAGE_SIZE; |
2830 | case RES_LIMIT: | |
2831 | return (u64)counter->limit * PAGE_SIZE; | |
2832 | case RES_MAX_USAGE: | |
2833 | return (u64)counter->watermark * PAGE_SIZE; | |
2834 | case RES_FAILCNT: | |
2835 | return counter->failcnt; | |
2836 | case RES_SOFT_LIMIT: | |
2837 | return (u64)memcg->soft_limit * PAGE_SIZE; | |
2838 | default: | |
2839 | BUG(); | |
2840 | } | |
8cdea7c0 | 2841 | } |
510fc4e1 | 2842 | |
127424c8 | 2843 | #ifndef CONFIG_SLOB |
567e9ab2 | 2844 | static int memcg_online_kmem(struct mem_cgroup *memcg) |
d6441637 | 2845 | { |
d6441637 VD |
2846 | int memcg_id; |
2847 | ||
2a4db7eb | 2848 | BUG_ON(memcg->kmemcg_id >= 0); |
567e9ab2 | 2849 | BUG_ON(memcg->kmem_state); |
d6441637 | 2850 | |
f3bb3043 | 2851 | memcg_id = memcg_alloc_cache_id(); |
0b8f73e1 JW |
2852 | if (memcg_id < 0) |
2853 | return memcg_id; | |
d6441637 | 2854 | |
ef12947c | 2855 | static_branch_inc(&memcg_kmem_enabled_key); |
d6441637 | 2856 | /* |
567e9ab2 | 2857 | * A memory cgroup is considered kmem-online as soon as it gets |
900a38f0 | 2858 | * kmemcg_id. Setting the id after enabling static branching will |
d6441637 VD |
2859 | * guarantee no one starts accounting before all call sites are |
2860 | * patched. | |
2861 | */ | |
900a38f0 | 2862 | memcg->kmemcg_id = memcg_id; |
567e9ab2 | 2863 | memcg->kmem_state = KMEM_ONLINE; |
0b8f73e1 JW |
2864 | |
2865 | return 0; | |
d6441637 VD |
2866 | } |
2867 | ||
0b8f73e1 JW |
2868 | static int memcg_propagate_kmem(struct mem_cgroup *parent, |
2869 | struct mem_cgroup *memcg) | |
510fc4e1 | 2870 | { |
55007d84 | 2871 | int ret = 0; |
55007d84 | 2872 | |
8c0145b6 | 2873 | mutex_lock(&memcg_limit_mutex); |
55007d84 | 2874 | /* |
567e9ab2 JW |
2875 | * If the parent cgroup is not kmem-online now, it cannot be |
2876 | * onlined after this point, because it has at least one child | |
2877 | * already. | |
55007d84 | 2878 | */ |
04823c83 VD |
2879 | if (memcg_kmem_online(parent) || |
2880 | (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nokmem)) | |
567e9ab2 | 2881 | ret = memcg_online_kmem(memcg); |
8c0145b6 | 2882 | mutex_unlock(&memcg_limit_mutex); |
55007d84 | 2883 | return ret; |
510fc4e1 | 2884 | } |
8e0a8912 | 2885 | |
8e0a8912 JW |
2886 | static void memcg_offline_kmem(struct mem_cgroup *memcg) |
2887 | { | |
2888 | struct cgroup_subsys_state *css; | |
2889 | struct mem_cgroup *parent, *child; | |
2890 | int kmemcg_id; | |
2891 | ||
2892 | if (memcg->kmem_state != KMEM_ONLINE) | |
2893 | return; | |
2894 | /* | |
2895 | * Clear the online state before clearing memcg_caches array | |
2896 | * entries. The slab_mutex in memcg_deactivate_kmem_caches() | |
2897 | * guarantees that no cache will be created for this cgroup | |
2898 | * after we are done (see memcg_create_kmem_cache()). | |
2899 | */ | |
2900 | memcg->kmem_state = KMEM_ALLOCATED; | |
2901 | ||
2902 | memcg_deactivate_kmem_caches(memcg); | |
2903 | ||
2904 | kmemcg_id = memcg->kmemcg_id; | |
2905 | BUG_ON(kmemcg_id < 0); | |
2906 | ||
2907 | parent = parent_mem_cgroup(memcg); | |
2908 | if (!parent) | |
2909 | parent = root_mem_cgroup; | |
2910 | ||
2911 | /* | |
2912 | * Change kmemcg_id of this cgroup and all its descendants to the | |
2913 | * parent's id, and then move all entries from this cgroup's list_lrus | |
2914 | * to ones of the parent. After we have finished, all list_lrus | |
2915 | * corresponding to this cgroup are guaranteed to remain empty. The | |
2916 | * ordering is imposed by list_lru_node->lock taken by | |
2917 | * memcg_drain_all_list_lrus(). | |
2918 | */ | |
2919 | css_for_each_descendant_pre(css, &memcg->css) { | |
2920 | child = mem_cgroup_from_css(css); | |
2921 | BUG_ON(child->kmemcg_id != kmemcg_id); | |
2922 | child->kmemcg_id = parent->kmemcg_id; | |
2923 | if (!memcg->use_hierarchy) | |
2924 | break; | |
2925 | } | |
2926 | memcg_drain_all_list_lrus(kmemcg_id, parent->kmemcg_id); | |
2927 | ||
2928 | memcg_free_cache_id(kmemcg_id); | |
2929 | } | |
2930 | ||
2931 | static void memcg_free_kmem(struct mem_cgroup *memcg) | |
2932 | { | |
0b8f73e1 JW |
2933 | /* css_alloc() failed, offlining didn't happen */ |
2934 | if (unlikely(memcg->kmem_state == KMEM_ONLINE)) | |
2935 | memcg_offline_kmem(memcg); | |
2936 | ||
8e0a8912 JW |
2937 | if (memcg->kmem_state == KMEM_ALLOCATED) { |
2938 | memcg_destroy_kmem_caches(memcg); | |
2939 | static_branch_dec(&memcg_kmem_enabled_key); | |
2940 | WARN_ON(page_counter_read(&memcg->kmem)); | |
2941 | } | |
8e0a8912 | 2942 | } |
d6441637 | 2943 | #else |
0b8f73e1 JW |
2944 | static int memcg_propagate_kmem(struct mem_cgroup *parent, struct mem_cgroup *memcg) |
2945 | { | |
2946 | return 0; | |
2947 | } | |
2948 | static int memcg_online_kmem(struct mem_cgroup *memcg) | |
127424c8 JW |
2949 | { |
2950 | return 0; | |
2951 | } | |
2952 | static void memcg_offline_kmem(struct mem_cgroup *memcg) | |
2953 | { | |
2954 | } | |
2955 | static void memcg_free_kmem(struct mem_cgroup *memcg) | |
2956 | { | |
2957 | } | |
2958 | #endif /* !CONFIG_SLOB */ | |
2959 | ||
d6441637 | 2960 | static int memcg_update_kmem_limit(struct mem_cgroup *memcg, |
3e32cb2e | 2961 | unsigned long limit) |
d6441637 | 2962 | { |
0b8f73e1 | 2963 | int ret = 0; |
127424c8 JW |
2964 | |
2965 | mutex_lock(&memcg_limit_mutex); | |
2966 | /* Top-level cgroup doesn't propagate from root */ | |
2967 | if (!memcg_kmem_online(memcg)) { | |
0b8f73e1 JW |
2968 | if (cgroup_is_populated(memcg->css.cgroup) || |
2969 | (memcg->use_hierarchy && memcg_has_children(memcg))) | |
2970 | ret = -EBUSY; | |
2971 | if (ret) | |
2972 | goto out; | |
127424c8 JW |
2973 | ret = memcg_online_kmem(memcg); |
2974 | if (ret) | |
2975 | goto out; | |
2976 | } | |
2977 | ret = page_counter_limit(&memcg->kmem, limit); | |
2978 | out: | |
2979 | mutex_unlock(&memcg_limit_mutex); | |
2980 | return ret; | |
d6441637 | 2981 | } |
510fc4e1 | 2982 | |
d55f90bf VD |
2983 | static int memcg_update_tcp_limit(struct mem_cgroup *memcg, unsigned long limit) |
2984 | { | |
2985 | int ret; | |
2986 | ||
2987 | mutex_lock(&memcg_limit_mutex); | |
2988 | ||
0db15298 | 2989 | ret = page_counter_limit(&memcg->tcpmem, limit); |
d55f90bf VD |
2990 | if (ret) |
2991 | goto out; | |
2992 | ||
0db15298 | 2993 | if (!memcg->tcpmem_active) { |
d55f90bf VD |
2994 | /* |
2995 | * The active flag needs to be written after the static_key | |
2996 | * update. This is what guarantees that the socket activation | |
2997 | * function is the last one to run. See sock_update_memcg() for | |
2998 | * details, and note that we don't mark any socket as belonging | |
2999 | * to this memcg until that flag is up. | |
3000 | * | |
3001 | * We need to do this, because static_keys will span multiple | |
3002 | * sites, but we can't control their order. If we mark a socket | |
3003 | * as accounted, but the accounting functions are not patched in | |
3004 | * yet, we'll lose accounting. | |
3005 | * | |
3006 | * We never race with the readers in sock_update_memcg(), | |
3007 | * because when this value change, the code to process it is not | |
3008 | * patched in yet. | |
3009 | */ | |
3010 | static_branch_inc(&memcg_sockets_enabled_key); | |
0db15298 | 3011 | memcg->tcpmem_active = true; |
d55f90bf VD |
3012 | } |
3013 | out: | |
3014 | mutex_unlock(&memcg_limit_mutex); | |
3015 | return ret; | |
3016 | } | |
d55f90bf | 3017 | |
628f4235 KH |
3018 | /* |
3019 | * The user of this function is... | |
3020 | * RES_LIMIT. | |
3021 | */ | |
451af504 TH |
3022 | static ssize_t mem_cgroup_write(struct kernfs_open_file *of, |
3023 | char *buf, size_t nbytes, loff_t off) | |
8cdea7c0 | 3024 | { |
451af504 | 3025 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 3026 | unsigned long nr_pages; |
628f4235 KH |
3027 | int ret; |
3028 | ||
451af504 | 3029 | buf = strstrip(buf); |
650c5e56 | 3030 | ret = page_counter_memparse(buf, "-1", &nr_pages); |
3e32cb2e JW |
3031 | if (ret) |
3032 | return ret; | |
af36f906 | 3033 | |
3e32cb2e | 3034 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
628f4235 | 3035 | case RES_LIMIT: |
4b3bde4c BS |
3036 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
3037 | ret = -EINVAL; | |
3038 | break; | |
3039 | } | |
3e32cb2e JW |
3040 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
3041 | case _MEM: | |
3042 | ret = mem_cgroup_resize_limit(memcg, nr_pages); | |
8c7c6e34 | 3043 | break; |
3e32cb2e JW |
3044 | case _MEMSWAP: |
3045 | ret = mem_cgroup_resize_memsw_limit(memcg, nr_pages); | |
296c81d8 | 3046 | break; |
3e32cb2e JW |
3047 | case _KMEM: |
3048 | ret = memcg_update_kmem_limit(memcg, nr_pages); | |
3049 | break; | |
d55f90bf VD |
3050 | case _TCP: |
3051 | ret = memcg_update_tcp_limit(memcg, nr_pages); | |
3052 | break; | |
3e32cb2e | 3053 | } |
296c81d8 | 3054 | break; |
3e32cb2e JW |
3055 | case RES_SOFT_LIMIT: |
3056 | memcg->soft_limit = nr_pages; | |
3057 | ret = 0; | |
628f4235 KH |
3058 | break; |
3059 | } | |
451af504 | 3060 | return ret ?: nbytes; |
8cdea7c0 BS |
3061 | } |
3062 | ||
6770c64e TH |
3063 | static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf, |
3064 | size_t nbytes, loff_t off) | |
c84872e1 | 3065 | { |
6770c64e | 3066 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); |
3e32cb2e | 3067 | struct page_counter *counter; |
c84872e1 | 3068 | |
3e32cb2e JW |
3069 | switch (MEMFILE_TYPE(of_cft(of)->private)) { |
3070 | case _MEM: | |
3071 | counter = &memcg->memory; | |
3072 | break; | |
3073 | case _MEMSWAP: | |
3074 | counter = &memcg->memsw; | |
3075 | break; | |
3076 | case _KMEM: | |
3077 | counter = &memcg->kmem; | |
3078 | break; | |
d55f90bf | 3079 | case _TCP: |
0db15298 | 3080 | counter = &memcg->tcpmem; |
d55f90bf | 3081 | break; |
3e32cb2e JW |
3082 | default: |
3083 | BUG(); | |
3084 | } | |
af36f906 | 3085 | |
3e32cb2e | 3086 | switch (MEMFILE_ATTR(of_cft(of)->private)) { |
29f2a4da | 3087 | case RES_MAX_USAGE: |
3e32cb2e | 3088 | page_counter_reset_watermark(counter); |
29f2a4da PE |
3089 | break; |
3090 | case RES_FAILCNT: | |
3e32cb2e | 3091 | counter->failcnt = 0; |
29f2a4da | 3092 | break; |
3e32cb2e JW |
3093 | default: |
3094 | BUG(); | |
29f2a4da | 3095 | } |
f64c3f54 | 3096 | |
6770c64e | 3097 | return nbytes; |
c84872e1 PE |
3098 | } |
3099 | ||
182446d0 | 3100 | static u64 mem_cgroup_move_charge_read(struct cgroup_subsys_state *css, |
7dc74be0 DN |
3101 | struct cftype *cft) |
3102 | { | |
182446d0 | 3103 | return mem_cgroup_from_css(css)->move_charge_at_immigrate; |
7dc74be0 DN |
3104 | } |
3105 | ||
02491447 | 3106 | #ifdef CONFIG_MMU |
182446d0 | 3107 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
7dc74be0 DN |
3108 | struct cftype *cft, u64 val) |
3109 | { | |
182446d0 | 3110 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
7dc74be0 | 3111 | |
1dfab5ab | 3112 | if (val & ~MOVE_MASK) |
7dc74be0 | 3113 | return -EINVAL; |
ee5e8472 | 3114 | |
7dc74be0 | 3115 | /* |
ee5e8472 GC |
3116 | * No kind of locking is needed in here, because ->can_attach() will |
3117 | * check this value once in the beginning of the process, and then carry | |
3118 | * on with stale data. This means that changes to this value will only | |
3119 | * affect task migrations starting after the change. | |
7dc74be0 | 3120 | */ |
c0ff4b85 | 3121 | memcg->move_charge_at_immigrate = val; |
7dc74be0 DN |
3122 | return 0; |
3123 | } | |
02491447 | 3124 | #else |
182446d0 | 3125 | static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, |
02491447 DN |
3126 | struct cftype *cft, u64 val) |
3127 | { | |
3128 | return -ENOSYS; | |
3129 | } | |
3130 | #endif | |
7dc74be0 | 3131 | |
406eb0c9 | 3132 | #ifdef CONFIG_NUMA |
2da8ca82 | 3133 | static int memcg_numa_stat_show(struct seq_file *m, void *v) |
406eb0c9 | 3134 | { |
25485de6 GT |
3135 | struct numa_stat { |
3136 | const char *name; | |
3137 | unsigned int lru_mask; | |
3138 | }; | |
3139 | ||
3140 | static const struct numa_stat stats[] = { | |
3141 | { "total", LRU_ALL }, | |
3142 | { "file", LRU_ALL_FILE }, | |
3143 | { "anon", LRU_ALL_ANON }, | |
3144 | { "unevictable", BIT(LRU_UNEVICTABLE) }, | |
3145 | }; | |
3146 | const struct numa_stat *stat; | |
406eb0c9 | 3147 | int nid; |
25485de6 | 3148 | unsigned long nr; |
2da8ca82 | 3149 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); |
406eb0c9 | 3150 | |
25485de6 GT |
3151 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
3152 | nr = mem_cgroup_nr_lru_pages(memcg, stat->lru_mask); | |
3153 | seq_printf(m, "%s=%lu", stat->name, nr); | |
3154 | for_each_node_state(nid, N_MEMORY) { | |
3155 | nr = mem_cgroup_node_nr_lru_pages(memcg, nid, | |
3156 | stat->lru_mask); | |
3157 | seq_printf(m, " N%d=%lu", nid, nr); | |
3158 | } | |
3159 | seq_putc(m, '\n'); | |
406eb0c9 | 3160 | } |
406eb0c9 | 3161 | |
071aee13 YH |
3162 | for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { |
3163 | struct mem_cgroup *iter; | |
3164 | ||
3165 | nr = 0; | |
3166 | for_each_mem_cgroup_tree(iter, memcg) | |
3167 | nr += mem_cgroup_nr_lru_pages(iter, stat->lru_mask); | |
3168 | seq_printf(m, "hierarchical_%s=%lu", stat->name, nr); | |
3169 | for_each_node_state(nid, N_MEMORY) { | |
3170 | nr = 0; | |
3171 | for_each_mem_cgroup_tree(iter, memcg) | |
3172 | nr += mem_cgroup_node_nr_lru_pages( | |
3173 | iter, nid, stat->lru_mask); | |
3174 | seq_printf(m, " N%d=%lu", nid, nr); | |
3175 | } | |
3176 | seq_putc(m, '\n'); | |
406eb0c9 | 3177 | } |
406eb0c9 | 3178 | |
406eb0c9 YH |
3179 | return 0; |
3180 | } | |
3181 | #endif /* CONFIG_NUMA */ | |
3182 | ||
2da8ca82 | 3183 | static int memcg_stat_show(struct seq_file *m, void *v) |
d2ceb9b7 | 3184 | { |
2da8ca82 | 3185 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); |
3e32cb2e | 3186 | unsigned long memory, memsw; |
af7c4b0e JW |
3187 | struct mem_cgroup *mi; |
3188 | unsigned int i; | |
406eb0c9 | 3189 | |
0ca44b14 GT |
3190 | BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_stat_names) != |
3191 | MEM_CGROUP_STAT_NSTATS); | |
3192 | BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_events_names) != | |
3193 | MEM_CGROUP_EVENTS_NSTATS); | |
70bc068c RS |
3194 | BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_lru_names) != NR_LRU_LISTS); |
3195 | ||
af7c4b0e | 3196 | for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) { |
7941d214 | 3197 | if (i == MEM_CGROUP_STAT_SWAP && !do_memsw_account()) |
1dd3a273 | 3198 | continue; |
484ebb3b | 3199 | seq_printf(m, "%s %lu\n", mem_cgroup_stat_names[i], |
af7c4b0e | 3200 | mem_cgroup_read_stat(memcg, i) * PAGE_SIZE); |
1dd3a273 | 3201 | } |
7b854121 | 3202 | |
af7c4b0e JW |
3203 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) |
3204 | seq_printf(m, "%s %lu\n", mem_cgroup_events_names[i], | |
3205 | mem_cgroup_read_events(memcg, i)); | |
3206 | ||
3207 | for (i = 0; i < NR_LRU_LISTS; i++) | |
3208 | seq_printf(m, "%s %lu\n", mem_cgroup_lru_names[i], | |
3209 | mem_cgroup_nr_lru_pages(memcg, BIT(i)) * PAGE_SIZE); | |
3210 | ||
14067bb3 | 3211 | /* Hierarchical information */ |
3e32cb2e JW |
3212 | memory = memsw = PAGE_COUNTER_MAX; |
3213 | for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) { | |
3214 | memory = min(memory, mi->memory.limit); | |
3215 | memsw = min(memsw, mi->memsw.limit); | |
fee7b548 | 3216 | } |
3e32cb2e JW |
3217 | seq_printf(m, "hierarchical_memory_limit %llu\n", |
3218 | (u64)memory * PAGE_SIZE); | |
7941d214 | 3219 | if (do_memsw_account()) |
3e32cb2e JW |
3220 | seq_printf(m, "hierarchical_memsw_limit %llu\n", |
3221 | (u64)memsw * PAGE_SIZE); | |
7f016ee8 | 3222 | |
af7c4b0e | 3223 | for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) { |
484ebb3b | 3224 | unsigned long long val = 0; |
af7c4b0e | 3225 | |
7941d214 | 3226 | if (i == MEM_CGROUP_STAT_SWAP && !do_memsw_account()) |
1dd3a273 | 3227 | continue; |
af7c4b0e JW |
3228 | for_each_mem_cgroup_tree(mi, memcg) |
3229 | val += mem_cgroup_read_stat(mi, i) * PAGE_SIZE; | |
484ebb3b | 3230 | seq_printf(m, "total_%s %llu\n", mem_cgroup_stat_names[i], val); |
af7c4b0e JW |
3231 | } |
3232 | ||
3233 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) { | |
3234 | unsigned long long val = 0; | |
3235 | ||
3236 | for_each_mem_cgroup_tree(mi, memcg) | |
3237 | val += mem_cgroup_read_events(mi, i); | |
3238 | seq_printf(m, "total_%s %llu\n", | |
3239 | mem_cgroup_events_names[i], val); | |
3240 | } | |
3241 | ||
3242 | for (i = 0; i < NR_LRU_LISTS; i++) { | |
3243 | unsigned long long val = 0; | |
3244 | ||
3245 | for_each_mem_cgroup_tree(mi, memcg) | |
3246 | val += mem_cgroup_nr_lru_pages(mi, BIT(i)) * PAGE_SIZE; | |
3247 | seq_printf(m, "total_%s %llu\n", mem_cgroup_lru_names[i], val); | |
1dd3a273 | 3248 | } |
14067bb3 | 3249 | |
7f016ee8 | 3250 | #ifdef CONFIG_DEBUG_VM |
7f016ee8 KM |
3251 | { |
3252 | int nid, zid; | |
3253 | struct mem_cgroup_per_zone *mz; | |
89abfab1 | 3254 | struct zone_reclaim_stat *rstat; |
7f016ee8 KM |
3255 | unsigned long recent_rotated[2] = {0, 0}; |
3256 | unsigned long recent_scanned[2] = {0, 0}; | |
3257 | ||
3258 | for_each_online_node(nid) | |
3259 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
e231875b | 3260 | mz = &memcg->nodeinfo[nid]->zoneinfo[zid]; |
89abfab1 | 3261 | rstat = &mz->lruvec.reclaim_stat; |
7f016ee8 | 3262 | |
89abfab1 HD |
3263 | recent_rotated[0] += rstat->recent_rotated[0]; |
3264 | recent_rotated[1] += rstat->recent_rotated[1]; | |
3265 | recent_scanned[0] += rstat->recent_scanned[0]; | |
3266 | recent_scanned[1] += rstat->recent_scanned[1]; | |
7f016ee8 | 3267 | } |
78ccf5b5 JW |
3268 | seq_printf(m, "recent_rotated_anon %lu\n", recent_rotated[0]); |
3269 | seq_printf(m, "recent_rotated_file %lu\n", recent_rotated[1]); | |
3270 | seq_printf(m, "recent_scanned_anon %lu\n", recent_scanned[0]); | |
3271 | seq_printf(m, "recent_scanned_file %lu\n", recent_scanned[1]); | |
7f016ee8 KM |
3272 | } |
3273 | #endif | |
3274 | ||
d2ceb9b7 KH |
3275 | return 0; |
3276 | } | |
3277 | ||
182446d0 TH |
3278 | static u64 mem_cgroup_swappiness_read(struct cgroup_subsys_state *css, |
3279 | struct cftype *cft) | |
a7885eb8 | 3280 | { |
182446d0 | 3281 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 3282 | |
1f4c025b | 3283 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
3284 | } |
3285 | ||
182446d0 TH |
3286 | static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, |
3287 | struct cftype *cft, u64 val) | |
a7885eb8 | 3288 | { |
182446d0 | 3289 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
a7885eb8 | 3290 | |
3dae7fec | 3291 | if (val > 100) |
a7885eb8 KM |
3292 | return -EINVAL; |
3293 | ||
14208b0e | 3294 | if (css->parent) |
3dae7fec JW |
3295 | memcg->swappiness = val; |
3296 | else | |
3297 | vm_swappiness = val; | |
068b38c1 | 3298 | |
a7885eb8 KM |
3299 | return 0; |
3300 | } | |
3301 | ||
2e72b634 KS |
3302 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
3303 | { | |
3304 | struct mem_cgroup_threshold_ary *t; | |
3e32cb2e | 3305 | unsigned long usage; |
2e72b634 KS |
3306 | int i; |
3307 | ||
3308 | rcu_read_lock(); | |
3309 | if (!swap) | |
2c488db2 | 3310 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 3311 | else |
2c488db2 | 3312 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
3313 | |
3314 | if (!t) | |
3315 | goto unlock; | |
3316 | ||
ce00a967 | 3317 | usage = mem_cgroup_usage(memcg, swap); |
2e72b634 KS |
3318 | |
3319 | /* | |
748dad36 | 3320 | * current_threshold points to threshold just below or equal to usage. |
2e72b634 KS |
3321 | * If it's not true, a threshold was crossed after last |
3322 | * call of __mem_cgroup_threshold(). | |
3323 | */ | |
5407a562 | 3324 | i = t->current_threshold; |
2e72b634 KS |
3325 | |
3326 | /* | |
3327 | * Iterate backward over array of thresholds starting from | |
3328 | * current_threshold and check if a threshold is crossed. | |
3329 | * If none of thresholds below usage is crossed, we read | |
3330 | * only one element of the array here. | |
3331 | */ | |
3332 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
3333 | eventfd_signal(t->entries[i].eventfd, 1); | |
3334 | ||
3335 | /* i = current_threshold + 1 */ | |
3336 | i++; | |
3337 | ||
3338 | /* | |
3339 | * Iterate forward over array of thresholds starting from | |
3340 | * current_threshold+1 and check if a threshold is crossed. | |
3341 | * If none of thresholds above usage is crossed, we read | |
3342 | * only one element of the array here. | |
3343 | */ | |
3344 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
3345 | eventfd_signal(t->entries[i].eventfd, 1); | |
3346 | ||
3347 | /* Update current_threshold */ | |
5407a562 | 3348 | t->current_threshold = i - 1; |
2e72b634 KS |
3349 | unlock: |
3350 | rcu_read_unlock(); | |
3351 | } | |
3352 | ||
3353 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
3354 | { | |
ad4ca5f4 KS |
3355 | while (memcg) { |
3356 | __mem_cgroup_threshold(memcg, false); | |
7941d214 | 3357 | if (do_memsw_account()) |
ad4ca5f4 KS |
3358 | __mem_cgroup_threshold(memcg, true); |
3359 | ||
3360 | memcg = parent_mem_cgroup(memcg); | |
3361 | } | |
2e72b634 KS |
3362 | } |
3363 | ||
3364 | static int compare_thresholds(const void *a, const void *b) | |
3365 | { | |
3366 | const struct mem_cgroup_threshold *_a = a; | |
3367 | const struct mem_cgroup_threshold *_b = b; | |
3368 | ||
2bff24a3 GT |
3369 | if (_a->threshold > _b->threshold) |
3370 | return 1; | |
3371 | ||
3372 | if (_a->threshold < _b->threshold) | |
3373 | return -1; | |
3374 | ||
3375 | return 0; | |
2e72b634 KS |
3376 | } |
3377 | ||
c0ff4b85 | 3378 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg) |
9490ff27 KH |
3379 | { |
3380 | struct mem_cgroup_eventfd_list *ev; | |
3381 | ||
2bcf2e92 MH |
3382 | spin_lock(&memcg_oom_lock); |
3383 | ||
c0ff4b85 | 3384 | list_for_each_entry(ev, &memcg->oom_notify, list) |
9490ff27 | 3385 | eventfd_signal(ev->eventfd, 1); |
2bcf2e92 MH |
3386 | |
3387 | spin_unlock(&memcg_oom_lock); | |
9490ff27 KH |
3388 | return 0; |
3389 | } | |
3390 | ||
c0ff4b85 | 3391 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) |
9490ff27 | 3392 | { |
7d74b06f KH |
3393 | struct mem_cgroup *iter; |
3394 | ||
c0ff4b85 | 3395 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 3396 | mem_cgroup_oom_notify_cb(iter); |
9490ff27 KH |
3397 | } |
3398 | ||
59b6f873 | 3399 | static int __mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 | 3400 | struct eventfd_ctx *eventfd, const char *args, enum res_type type) |
2e72b634 | 3401 | { |
2c488db2 KS |
3402 | struct mem_cgroup_thresholds *thresholds; |
3403 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e JW |
3404 | unsigned long threshold; |
3405 | unsigned long usage; | |
2c488db2 | 3406 | int i, size, ret; |
2e72b634 | 3407 | |
650c5e56 | 3408 | ret = page_counter_memparse(args, "-1", &threshold); |
2e72b634 KS |
3409 | if (ret) |
3410 | return ret; | |
3411 | ||
3412 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 3413 | |
05b84301 | 3414 | if (type == _MEM) { |
2c488db2 | 3415 | thresholds = &memcg->thresholds; |
ce00a967 | 3416 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 3417 | } else if (type == _MEMSWAP) { |
2c488db2 | 3418 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 3419 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 3420 | } else |
2e72b634 KS |
3421 | BUG(); |
3422 | ||
2e72b634 | 3423 | /* Check if a threshold crossed before adding a new one */ |
2c488db2 | 3424 | if (thresholds->primary) |
2e72b634 KS |
3425 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
3426 | ||
2c488db2 | 3427 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
3428 | |
3429 | /* Allocate memory for new array of thresholds */ | |
2c488db2 | 3430 | new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold), |
2e72b634 | 3431 | GFP_KERNEL); |
2c488db2 | 3432 | if (!new) { |
2e72b634 KS |
3433 | ret = -ENOMEM; |
3434 | goto unlock; | |
3435 | } | |
2c488db2 | 3436 | new->size = size; |
2e72b634 KS |
3437 | |
3438 | /* Copy thresholds (if any) to new array */ | |
2c488db2 KS |
3439 | if (thresholds->primary) { |
3440 | memcpy(new->entries, thresholds->primary->entries, (size - 1) * | |
2e72b634 | 3441 | sizeof(struct mem_cgroup_threshold)); |
2c488db2 KS |
3442 | } |
3443 | ||
2e72b634 | 3444 | /* Add new threshold */ |
2c488db2 KS |
3445 | new->entries[size - 1].eventfd = eventfd; |
3446 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
3447 | |
3448 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
2c488db2 | 3449 | sort(new->entries, size, sizeof(struct mem_cgroup_threshold), |
2e72b634 KS |
3450 | compare_thresholds, NULL); |
3451 | ||
3452 | /* Find current threshold */ | |
2c488db2 | 3453 | new->current_threshold = -1; |
2e72b634 | 3454 | for (i = 0; i < size; i++) { |
748dad36 | 3455 | if (new->entries[i].threshold <= usage) { |
2e72b634 | 3456 | /* |
2c488db2 KS |
3457 | * new->current_threshold will not be used until |
3458 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
3459 | * it here. |
3460 | */ | |
2c488db2 | 3461 | ++new->current_threshold; |
748dad36 SZ |
3462 | } else |
3463 | break; | |
2e72b634 KS |
3464 | } |
3465 | ||
2c488db2 KS |
3466 | /* Free old spare buffer and save old primary buffer as spare */ |
3467 | kfree(thresholds->spare); | |
3468 | thresholds->spare = thresholds->primary; | |
3469 | ||
3470 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 3471 | |
907860ed | 3472 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
3473 | synchronize_rcu(); |
3474 | ||
2e72b634 KS |
3475 | unlock: |
3476 | mutex_unlock(&memcg->thresholds_lock); | |
3477 | ||
3478 | return ret; | |
3479 | } | |
3480 | ||
59b6f873 | 3481 | static int mem_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
3482 | struct eventfd_ctx *eventfd, const char *args) |
3483 | { | |
59b6f873 | 3484 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEM); |
347c4a87 TH |
3485 | } |
3486 | ||
59b6f873 | 3487 | static int memsw_cgroup_usage_register_event(struct mem_cgroup *memcg, |
347c4a87 TH |
3488 | struct eventfd_ctx *eventfd, const char *args) |
3489 | { | |
59b6f873 | 3490 | return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEMSWAP); |
347c4a87 TH |
3491 | } |
3492 | ||
59b6f873 | 3493 | static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 3494 | struct eventfd_ctx *eventfd, enum res_type type) |
2e72b634 | 3495 | { |
2c488db2 KS |
3496 | struct mem_cgroup_thresholds *thresholds; |
3497 | struct mem_cgroup_threshold_ary *new; | |
3e32cb2e | 3498 | unsigned long usage; |
2c488db2 | 3499 | int i, j, size; |
2e72b634 KS |
3500 | |
3501 | mutex_lock(&memcg->thresholds_lock); | |
05b84301 JW |
3502 | |
3503 | if (type == _MEM) { | |
2c488db2 | 3504 | thresholds = &memcg->thresholds; |
ce00a967 | 3505 | usage = mem_cgroup_usage(memcg, false); |
05b84301 | 3506 | } else if (type == _MEMSWAP) { |
2c488db2 | 3507 | thresholds = &memcg->memsw_thresholds; |
ce00a967 | 3508 | usage = mem_cgroup_usage(memcg, true); |
05b84301 | 3509 | } else |
2e72b634 KS |
3510 | BUG(); |
3511 | ||
371528ca AV |
3512 | if (!thresholds->primary) |
3513 | goto unlock; | |
3514 | ||
2e72b634 KS |
3515 | /* Check if a threshold crossed before removing */ |
3516 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
3517 | ||
3518 | /* Calculate new number of threshold */ | |
2c488db2 KS |
3519 | size = 0; |
3520 | for (i = 0; i < thresholds->primary->size; i++) { | |
3521 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 KS |
3522 | size++; |
3523 | } | |
3524 | ||
2c488db2 | 3525 | new = thresholds->spare; |
907860ed | 3526 | |
2e72b634 KS |
3527 | /* Set thresholds array to NULL if we don't have thresholds */ |
3528 | if (!size) { | |
2c488db2 KS |
3529 | kfree(new); |
3530 | new = NULL; | |
907860ed | 3531 | goto swap_buffers; |
2e72b634 KS |
3532 | } |
3533 | ||
2c488db2 | 3534 | new->size = size; |
2e72b634 KS |
3535 | |
3536 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
3537 | new->current_threshold = -1; |
3538 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
3539 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
3540 | continue; |
3541 | ||
2c488db2 | 3542 | new->entries[j] = thresholds->primary->entries[i]; |
748dad36 | 3543 | if (new->entries[j].threshold <= usage) { |
2e72b634 | 3544 | /* |
2c488db2 | 3545 | * new->current_threshold will not be used |
2e72b634 KS |
3546 | * until rcu_assign_pointer(), so it's safe to increment |
3547 | * it here. | |
3548 | */ | |
2c488db2 | 3549 | ++new->current_threshold; |
2e72b634 KS |
3550 | } |
3551 | j++; | |
3552 | } | |
3553 | ||
907860ed | 3554 | swap_buffers: |
2c488db2 KS |
3555 | /* Swap primary and spare array */ |
3556 | thresholds->spare = thresholds->primary; | |
8c757763 | 3557 | |
2c488db2 | 3558 | rcu_assign_pointer(thresholds->primary, new); |
2e72b634 | 3559 | |
907860ed | 3560 | /* To be sure that nobody uses thresholds */ |
2e72b634 | 3561 | synchronize_rcu(); |
6611d8d7 MC |
3562 | |
3563 | /* If all events are unregistered, free the spare array */ | |
3564 | if (!new) { | |
3565 | kfree(thresholds->spare); | |
3566 | thresholds->spare = NULL; | |
3567 | } | |
371528ca | 3568 | unlock: |
2e72b634 | 3569 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 3570 | } |
c1e862c1 | 3571 | |
59b6f873 | 3572 | static void mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
3573 | struct eventfd_ctx *eventfd) |
3574 | { | |
59b6f873 | 3575 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEM); |
347c4a87 TH |
3576 | } |
3577 | ||
59b6f873 | 3578 | static void memsw_cgroup_usage_unregister_event(struct mem_cgroup *memcg, |
347c4a87 TH |
3579 | struct eventfd_ctx *eventfd) |
3580 | { | |
59b6f873 | 3581 | return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEMSWAP); |
347c4a87 TH |
3582 | } |
3583 | ||
59b6f873 | 3584 | static int mem_cgroup_oom_register_event(struct mem_cgroup *memcg, |
347c4a87 | 3585 | struct eventfd_ctx *eventfd, const char *args) |
9490ff27 | 3586 | { |
9490ff27 | 3587 | struct mem_cgroup_eventfd_list *event; |
9490ff27 | 3588 | |
9490ff27 KH |
3589 | event = kmalloc(sizeof(*event), GFP_KERNEL); |
3590 | if (!event) | |
3591 | return -ENOMEM; | |
3592 | ||
1af8efe9 | 3593 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
3594 | |
3595 | event->eventfd = eventfd; | |
3596 | list_add(&event->list, &memcg->oom_notify); | |
3597 | ||
3598 | /* already in OOM ? */ | |
c2b42d3c | 3599 | if (memcg->under_oom) |
9490ff27 | 3600 | eventfd_signal(eventfd, 1); |
1af8efe9 | 3601 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
3602 | |
3603 | return 0; | |
3604 | } | |
3605 | ||
59b6f873 | 3606 | static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg, |
347c4a87 | 3607 | struct eventfd_ctx *eventfd) |
9490ff27 | 3608 | { |
9490ff27 | 3609 | struct mem_cgroup_eventfd_list *ev, *tmp; |
9490ff27 | 3610 | |
1af8efe9 | 3611 | spin_lock(&memcg_oom_lock); |
9490ff27 | 3612 | |
c0ff4b85 | 3613 | list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) { |
9490ff27 KH |
3614 | if (ev->eventfd == eventfd) { |
3615 | list_del(&ev->list); | |
3616 | kfree(ev); | |
3617 | } | |
3618 | } | |
3619 | ||
1af8efe9 | 3620 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
3621 | } |
3622 | ||
2da8ca82 | 3623 | static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v) |
3c11ecf4 | 3624 | { |
2da8ca82 | 3625 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(sf)); |
3c11ecf4 | 3626 | |
791badbd | 3627 | seq_printf(sf, "oom_kill_disable %d\n", memcg->oom_kill_disable); |
c2b42d3c | 3628 | seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom); |
3c11ecf4 KH |
3629 | return 0; |
3630 | } | |
3631 | ||
182446d0 | 3632 | static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css, |
3c11ecf4 KH |
3633 | struct cftype *cft, u64 val) |
3634 | { | |
182446d0 | 3635 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3c11ecf4 KH |
3636 | |
3637 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
14208b0e | 3638 | if (!css->parent || !((val == 0) || (val == 1))) |
3c11ecf4 KH |
3639 | return -EINVAL; |
3640 | ||
c0ff4b85 | 3641 | memcg->oom_kill_disable = val; |
4d845ebf | 3642 | if (!val) |
c0ff4b85 | 3643 | memcg_oom_recover(memcg); |
3dae7fec | 3644 | |
3c11ecf4 KH |
3645 | return 0; |
3646 | } | |
3647 | ||
52ebea74 TH |
3648 | #ifdef CONFIG_CGROUP_WRITEBACK |
3649 | ||
3650 | struct list_head *mem_cgroup_cgwb_list(struct mem_cgroup *memcg) | |
3651 | { | |
3652 | return &memcg->cgwb_list; | |
3653 | } | |
3654 | ||
841710aa TH |
3655 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) |
3656 | { | |
3657 | return wb_domain_init(&memcg->cgwb_domain, gfp); | |
3658 | } | |
3659 | ||
3660 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
3661 | { | |
3662 | wb_domain_exit(&memcg->cgwb_domain); | |
3663 | } | |
3664 | ||
2529bb3a TH |
3665 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
3666 | { | |
3667 | wb_domain_size_changed(&memcg->cgwb_domain); | |
3668 | } | |
3669 | ||
841710aa TH |
3670 | struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb) |
3671 | { | |
3672 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
3673 | ||
3674 | if (!memcg->css.parent) | |
3675 | return NULL; | |
3676 | ||
3677 | return &memcg->cgwb_domain; | |
3678 | } | |
3679 | ||
c2aa723a TH |
3680 | /** |
3681 | * mem_cgroup_wb_stats - retrieve writeback related stats from its memcg | |
3682 | * @wb: bdi_writeback in question | |
c5edf9cd TH |
3683 | * @pfilepages: out parameter for number of file pages |
3684 | * @pheadroom: out parameter for number of allocatable pages according to memcg | |
c2aa723a TH |
3685 | * @pdirty: out parameter for number of dirty pages |
3686 | * @pwriteback: out parameter for number of pages under writeback | |
3687 | * | |
c5edf9cd TH |
3688 | * Determine the numbers of file, headroom, dirty, and writeback pages in |
3689 | * @wb's memcg. File, dirty and writeback are self-explanatory. Headroom | |
3690 | * is a bit more involved. | |
c2aa723a | 3691 | * |
c5edf9cd TH |
3692 | * A memcg's headroom is "min(max, high) - used". In the hierarchy, the |
3693 | * headroom is calculated as the lowest headroom of itself and the | |
3694 | * ancestors. Note that this doesn't consider the actual amount of | |
3695 | * available memory in the system. The caller should further cap | |
3696 | * *@pheadroom accordingly. | |
c2aa723a | 3697 | */ |
c5edf9cd TH |
3698 | void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, |
3699 | unsigned long *pheadroom, unsigned long *pdirty, | |
3700 | unsigned long *pwriteback) | |
c2aa723a TH |
3701 | { |
3702 | struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); | |
3703 | struct mem_cgroup *parent; | |
c2aa723a TH |
3704 | |
3705 | *pdirty = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_DIRTY); | |
3706 | ||
3707 | /* this should eventually include NR_UNSTABLE_NFS */ | |
3708 | *pwriteback = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_WRITEBACK); | |
c5edf9cd TH |
3709 | *pfilepages = mem_cgroup_nr_lru_pages(memcg, (1 << LRU_INACTIVE_FILE) | |
3710 | (1 << LRU_ACTIVE_FILE)); | |
3711 | *pheadroom = PAGE_COUNTER_MAX; | |
c2aa723a | 3712 | |
c2aa723a TH |
3713 | while ((parent = parent_mem_cgroup(memcg))) { |
3714 | unsigned long ceiling = min(memcg->memory.limit, memcg->high); | |
3715 | unsigned long used = page_counter_read(&memcg->memory); | |
3716 | ||
c5edf9cd | 3717 | *pheadroom = min(*pheadroom, ceiling - min(ceiling, used)); |
c2aa723a TH |
3718 | memcg = parent; |
3719 | } | |
c2aa723a TH |
3720 | } |
3721 | ||
841710aa TH |
3722 | #else /* CONFIG_CGROUP_WRITEBACK */ |
3723 | ||
3724 | static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp) | |
3725 | { | |
3726 | return 0; | |
3727 | } | |
3728 | ||
3729 | static void memcg_wb_domain_exit(struct mem_cgroup *memcg) | |
3730 | { | |
3731 | } | |
3732 | ||
2529bb3a TH |
3733 | static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg) |
3734 | { | |
3735 | } | |
3736 | ||
52ebea74 TH |
3737 | #endif /* CONFIG_CGROUP_WRITEBACK */ |
3738 | ||
3bc942f3 TH |
3739 | /* |
3740 | * DO NOT USE IN NEW FILES. | |
3741 | * | |
3742 | * "cgroup.event_control" implementation. | |
3743 | * | |
3744 | * This is way over-engineered. It tries to support fully configurable | |
3745 | * events for each user. Such level of flexibility is completely | |
3746 | * unnecessary especially in the light of the planned unified hierarchy. | |
3747 | * | |
3748 | * Please deprecate this and replace with something simpler if at all | |
3749 | * possible. | |
3750 | */ | |
3751 | ||
79bd9814 TH |
3752 | /* |
3753 | * Unregister event and free resources. | |
3754 | * | |
3755 | * Gets called from workqueue. | |
3756 | */ | |
3bc942f3 | 3757 | static void memcg_event_remove(struct work_struct *work) |
79bd9814 | 3758 | { |
3bc942f3 TH |
3759 | struct mem_cgroup_event *event = |
3760 | container_of(work, struct mem_cgroup_event, remove); | |
59b6f873 | 3761 | struct mem_cgroup *memcg = event->memcg; |
79bd9814 TH |
3762 | |
3763 | remove_wait_queue(event->wqh, &event->wait); | |
3764 | ||
59b6f873 | 3765 | event->unregister_event(memcg, event->eventfd); |
79bd9814 TH |
3766 | |
3767 | /* Notify userspace the event is going away. */ | |
3768 | eventfd_signal(event->eventfd, 1); | |
3769 | ||
3770 | eventfd_ctx_put(event->eventfd); | |
3771 | kfree(event); | |
59b6f873 | 3772 | css_put(&memcg->css); |
79bd9814 TH |
3773 | } |
3774 | ||
3775 | /* | |
3776 | * Gets called on POLLHUP on eventfd when user closes it. | |
3777 | * | |
3778 | * Called with wqh->lock held and interrupts disabled. | |
3779 | */ | |
3bc942f3 TH |
3780 | static int memcg_event_wake(wait_queue_t *wait, unsigned mode, |
3781 | int sync, void *key) | |
79bd9814 | 3782 | { |
3bc942f3 TH |
3783 | struct mem_cgroup_event *event = |
3784 | container_of(wait, struct mem_cgroup_event, wait); | |
59b6f873 | 3785 | struct mem_cgroup *memcg = event->memcg; |
79bd9814 TH |
3786 | unsigned long flags = (unsigned long)key; |
3787 | ||
3788 | if (flags & POLLHUP) { | |
3789 | /* | |
3790 | * If the event has been detached at cgroup removal, we | |
3791 | * can simply return knowing the other side will cleanup | |
3792 | * for us. | |
3793 | * | |
3794 | * We can't race against event freeing since the other | |
3795 | * side will require wqh->lock via remove_wait_queue(), | |
3796 | * which we hold. | |
3797 | */ | |
fba94807 | 3798 | spin_lock(&memcg->event_list_lock); |
79bd9814 TH |
3799 | if (!list_empty(&event->list)) { |
3800 | list_del_init(&event->list); | |
3801 | /* | |
3802 | * We are in atomic context, but cgroup_event_remove() | |
3803 | * may sleep, so we have to call it in workqueue. | |
3804 | */ | |
3805 | schedule_work(&event->remove); | |
3806 | } | |
fba94807 | 3807 | spin_unlock(&memcg->event_list_lock); |
79bd9814 TH |
3808 | } |
3809 | ||
3810 | return 0; | |
3811 | } | |
3812 | ||
3bc942f3 | 3813 | static void memcg_event_ptable_queue_proc(struct file *file, |
79bd9814 TH |
3814 | wait_queue_head_t *wqh, poll_table *pt) |
3815 | { | |
3bc942f3 TH |
3816 | struct mem_cgroup_event *event = |
3817 | container_of(pt, struct mem_cgroup_event, pt); | |
79bd9814 TH |
3818 | |
3819 | event->wqh = wqh; | |
3820 | add_wait_queue(wqh, &event->wait); | |
3821 | } | |
3822 | ||
3823 | /* | |
3bc942f3 TH |
3824 | * DO NOT USE IN NEW FILES. |
3825 | * | |
79bd9814 TH |
3826 | * Parse input and register new cgroup event handler. |
3827 | * | |
3828 | * Input must be in format '<event_fd> <control_fd> <args>'. | |
3829 | * Interpretation of args is defined by control file implementation. | |
3830 | */ | |
451af504 TH |
3831 | static ssize_t memcg_write_event_control(struct kernfs_open_file *of, |
3832 | char *buf, size_t nbytes, loff_t off) | |
79bd9814 | 3833 | { |
451af504 | 3834 | struct cgroup_subsys_state *css = of_css(of); |
fba94807 | 3835 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 3836 | struct mem_cgroup_event *event; |
79bd9814 TH |
3837 | struct cgroup_subsys_state *cfile_css; |
3838 | unsigned int efd, cfd; | |
3839 | struct fd efile; | |
3840 | struct fd cfile; | |
fba94807 | 3841 | const char *name; |
79bd9814 TH |
3842 | char *endp; |
3843 | int ret; | |
3844 | ||
451af504 TH |
3845 | buf = strstrip(buf); |
3846 | ||
3847 | efd = simple_strtoul(buf, &endp, 10); | |
79bd9814 TH |
3848 | if (*endp != ' ') |
3849 | return -EINVAL; | |
451af504 | 3850 | buf = endp + 1; |
79bd9814 | 3851 | |
451af504 | 3852 | cfd = simple_strtoul(buf, &endp, 10); |
79bd9814 TH |
3853 | if ((*endp != ' ') && (*endp != '\0')) |
3854 | return -EINVAL; | |
451af504 | 3855 | buf = endp + 1; |
79bd9814 TH |
3856 | |
3857 | event = kzalloc(sizeof(*event), GFP_KERNEL); | |
3858 | if (!event) | |
3859 | return -ENOMEM; | |
3860 | ||
59b6f873 | 3861 | event->memcg = memcg; |
79bd9814 | 3862 | INIT_LIST_HEAD(&event->list); |
3bc942f3 TH |
3863 | init_poll_funcptr(&event->pt, memcg_event_ptable_queue_proc); |
3864 | init_waitqueue_func_entry(&event->wait, memcg_event_wake); | |
3865 | INIT_WORK(&event->remove, memcg_event_remove); | |
79bd9814 TH |
3866 | |
3867 | efile = fdget(efd); | |
3868 | if (!efile.file) { | |
3869 | ret = -EBADF; | |
3870 | goto out_kfree; | |
3871 | } | |
3872 | ||
3873 | event->eventfd = eventfd_ctx_fileget(efile.file); | |
3874 | if (IS_ERR(event->eventfd)) { | |
3875 | ret = PTR_ERR(event->eventfd); | |
3876 | goto out_put_efile; | |
3877 | } | |
3878 | ||
3879 | cfile = fdget(cfd); | |
3880 | if (!cfile.file) { | |
3881 | ret = -EBADF; | |
3882 | goto out_put_eventfd; | |
3883 | } | |
3884 | ||
3885 | /* the process need read permission on control file */ | |
3886 | /* AV: shouldn't we check that it's been opened for read instead? */ | |
3887 | ret = inode_permission(file_inode(cfile.file), MAY_READ); | |
3888 | if (ret < 0) | |
3889 | goto out_put_cfile; | |
3890 | ||
fba94807 TH |
3891 | /* |
3892 | * Determine the event callbacks and set them in @event. This used | |
3893 | * to be done via struct cftype but cgroup core no longer knows | |
3894 | * about these events. The following is crude but the whole thing | |
3895 | * is for compatibility anyway. | |
3bc942f3 TH |
3896 | * |
3897 | * DO NOT ADD NEW FILES. | |
fba94807 | 3898 | */ |
b583043e | 3899 | name = cfile.file->f_path.dentry->d_name.name; |
fba94807 TH |
3900 | |
3901 | if (!strcmp(name, "memory.usage_in_bytes")) { | |
3902 | event->register_event = mem_cgroup_usage_register_event; | |
3903 | event->unregister_event = mem_cgroup_usage_unregister_event; | |
3904 | } else if (!strcmp(name, "memory.oom_control")) { | |
3905 | event->register_event = mem_cgroup_oom_register_event; | |
3906 | event->unregister_event = mem_cgroup_oom_unregister_event; | |
3907 | } else if (!strcmp(name, "memory.pressure_level")) { | |
3908 | event->register_event = vmpressure_register_event; | |
3909 | event->unregister_event = vmpressure_unregister_event; | |
3910 | } else if (!strcmp(name, "memory.memsw.usage_in_bytes")) { | |
347c4a87 TH |
3911 | event->register_event = memsw_cgroup_usage_register_event; |
3912 | event->unregister_event = memsw_cgroup_usage_unregister_event; | |
fba94807 TH |
3913 | } else { |
3914 | ret = -EINVAL; | |
3915 | goto out_put_cfile; | |
3916 | } | |
3917 | ||
79bd9814 | 3918 | /* |
b5557c4c TH |
3919 | * Verify @cfile should belong to @css. Also, remaining events are |
3920 | * automatically removed on cgroup destruction but the removal is | |
3921 | * asynchronous, so take an extra ref on @css. | |
79bd9814 | 3922 | */ |
b583043e | 3923 | cfile_css = css_tryget_online_from_dir(cfile.file->f_path.dentry->d_parent, |
ec903c0c | 3924 | &memory_cgrp_subsys); |
79bd9814 | 3925 | ret = -EINVAL; |
5a17f543 | 3926 | if (IS_ERR(cfile_css)) |
79bd9814 | 3927 | goto out_put_cfile; |
5a17f543 TH |
3928 | if (cfile_css != css) { |
3929 | css_put(cfile_css); | |
79bd9814 | 3930 | goto out_put_cfile; |
5a17f543 | 3931 | } |
79bd9814 | 3932 | |
451af504 | 3933 | ret = event->register_event(memcg, event->eventfd, buf); |
79bd9814 TH |
3934 | if (ret) |
3935 | goto out_put_css; | |
3936 | ||
3937 | efile.file->f_op->poll(efile.file, &event->pt); | |
3938 | ||
fba94807 TH |
3939 | spin_lock(&memcg->event_list_lock); |
3940 | list_add(&event->list, &memcg->event_list); | |
3941 | spin_unlock(&memcg->event_list_lock); | |
79bd9814 TH |
3942 | |
3943 | fdput(cfile); | |
3944 | fdput(efile); | |
3945 | ||
451af504 | 3946 | return nbytes; |
79bd9814 TH |
3947 | |
3948 | out_put_css: | |
b5557c4c | 3949 | css_put(css); |
79bd9814 TH |
3950 | out_put_cfile: |
3951 | fdput(cfile); | |
3952 | out_put_eventfd: | |
3953 | eventfd_ctx_put(event->eventfd); | |
3954 | out_put_efile: | |
3955 | fdput(efile); | |
3956 | out_kfree: | |
3957 | kfree(event); | |
3958 | ||
3959 | return ret; | |
3960 | } | |
3961 | ||
241994ed | 3962 | static struct cftype mem_cgroup_legacy_files[] = { |
8cdea7c0 | 3963 | { |
0eea1030 | 3964 | .name = "usage_in_bytes", |
8c7c6e34 | 3965 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
791badbd | 3966 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 3967 | }, |
c84872e1 PE |
3968 | { |
3969 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 3970 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
6770c64e | 3971 | .write = mem_cgroup_reset, |
791badbd | 3972 | .read_u64 = mem_cgroup_read_u64, |
c84872e1 | 3973 | }, |
8cdea7c0 | 3974 | { |
0eea1030 | 3975 | .name = "limit_in_bytes", |
8c7c6e34 | 3976 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
451af504 | 3977 | .write = mem_cgroup_write, |
791badbd | 3978 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 3979 | }, |
296c81d8 BS |
3980 | { |
3981 | .name = "soft_limit_in_bytes", | |
3982 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
451af504 | 3983 | .write = mem_cgroup_write, |
791badbd | 3984 | .read_u64 = mem_cgroup_read_u64, |
296c81d8 | 3985 | }, |
8cdea7c0 BS |
3986 | { |
3987 | .name = "failcnt", | |
8c7c6e34 | 3988 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
6770c64e | 3989 | .write = mem_cgroup_reset, |
791badbd | 3990 | .read_u64 = mem_cgroup_read_u64, |
8cdea7c0 | 3991 | }, |
d2ceb9b7 KH |
3992 | { |
3993 | .name = "stat", | |
2da8ca82 | 3994 | .seq_show = memcg_stat_show, |
d2ceb9b7 | 3995 | }, |
c1e862c1 KH |
3996 | { |
3997 | .name = "force_empty", | |
6770c64e | 3998 | .write = mem_cgroup_force_empty_write, |
c1e862c1 | 3999 | }, |
18f59ea7 BS |
4000 | { |
4001 | .name = "use_hierarchy", | |
4002 | .write_u64 = mem_cgroup_hierarchy_write, | |
4003 | .read_u64 = mem_cgroup_hierarchy_read, | |
4004 | }, | |
79bd9814 | 4005 | { |
3bc942f3 | 4006 | .name = "cgroup.event_control", /* XXX: for compat */ |
451af504 | 4007 | .write = memcg_write_event_control, |
7dbdb199 | 4008 | .flags = CFTYPE_NO_PREFIX | CFTYPE_WORLD_WRITABLE, |
79bd9814 | 4009 | }, |
a7885eb8 KM |
4010 | { |
4011 | .name = "swappiness", | |
4012 | .read_u64 = mem_cgroup_swappiness_read, | |
4013 | .write_u64 = mem_cgroup_swappiness_write, | |
4014 | }, | |
7dc74be0 DN |
4015 | { |
4016 | .name = "move_charge_at_immigrate", | |
4017 | .read_u64 = mem_cgroup_move_charge_read, | |
4018 | .write_u64 = mem_cgroup_move_charge_write, | |
4019 | }, | |
9490ff27 KH |
4020 | { |
4021 | .name = "oom_control", | |
2da8ca82 | 4022 | .seq_show = mem_cgroup_oom_control_read, |
3c11ecf4 | 4023 | .write_u64 = mem_cgroup_oom_control_write, |
9490ff27 KH |
4024 | .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), |
4025 | }, | |
70ddf637 AV |
4026 | { |
4027 | .name = "pressure_level", | |
70ddf637 | 4028 | }, |
406eb0c9 YH |
4029 | #ifdef CONFIG_NUMA |
4030 | { | |
4031 | .name = "numa_stat", | |
2da8ca82 | 4032 | .seq_show = memcg_numa_stat_show, |
406eb0c9 YH |
4033 | }, |
4034 | #endif | |
510fc4e1 GC |
4035 | { |
4036 | .name = "kmem.limit_in_bytes", | |
4037 | .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT), | |
451af504 | 4038 | .write = mem_cgroup_write, |
791badbd | 4039 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
4040 | }, |
4041 | { | |
4042 | .name = "kmem.usage_in_bytes", | |
4043 | .private = MEMFILE_PRIVATE(_KMEM, RES_USAGE), | |
791badbd | 4044 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
4045 | }, |
4046 | { | |
4047 | .name = "kmem.failcnt", | |
4048 | .private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT), | |
6770c64e | 4049 | .write = mem_cgroup_reset, |
791badbd | 4050 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 GC |
4051 | }, |
4052 | { | |
4053 | .name = "kmem.max_usage_in_bytes", | |
4054 | .private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE), | |
6770c64e | 4055 | .write = mem_cgroup_reset, |
791badbd | 4056 | .read_u64 = mem_cgroup_read_u64, |
510fc4e1 | 4057 | }, |
749c5415 GC |
4058 | #ifdef CONFIG_SLABINFO |
4059 | { | |
4060 | .name = "kmem.slabinfo", | |
b047501c VD |
4061 | .seq_start = slab_start, |
4062 | .seq_next = slab_next, | |
4063 | .seq_stop = slab_stop, | |
4064 | .seq_show = memcg_slab_show, | |
749c5415 GC |
4065 | }, |
4066 | #endif | |
d55f90bf VD |
4067 | { |
4068 | .name = "kmem.tcp.limit_in_bytes", | |
4069 | .private = MEMFILE_PRIVATE(_TCP, RES_LIMIT), | |
4070 | .write = mem_cgroup_write, | |
4071 | .read_u64 = mem_cgroup_read_u64, | |
4072 | }, | |
4073 | { | |
4074 | .name = "kmem.tcp.usage_in_bytes", | |
4075 | .private = MEMFILE_PRIVATE(_TCP, RES_USAGE), | |
4076 | .read_u64 = mem_cgroup_read_u64, | |
4077 | }, | |
4078 | { | |
4079 | .name = "kmem.tcp.failcnt", | |
4080 | .private = MEMFILE_PRIVATE(_TCP, RES_FAILCNT), | |
4081 | .write = mem_cgroup_reset, | |
4082 | .read_u64 = mem_cgroup_read_u64, | |
4083 | }, | |
4084 | { | |
4085 | .name = "kmem.tcp.max_usage_in_bytes", | |
4086 | .private = MEMFILE_PRIVATE(_TCP, RES_MAX_USAGE), | |
4087 | .write = mem_cgroup_reset, | |
4088 | .read_u64 = mem_cgroup_read_u64, | |
4089 | }, | |
6bc10349 | 4090 | { }, /* terminate */ |
af36f906 | 4091 | }; |
8c7c6e34 | 4092 | |
c0ff4b85 | 4093 | static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) |
6d12e2d8 KH |
4094 | { |
4095 | struct mem_cgroup_per_node *pn; | |
1ecaab2b | 4096 | struct mem_cgroup_per_zone *mz; |
41e3355d | 4097 | int zone, tmp = node; |
1ecaab2b KH |
4098 | /* |
4099 | * This routine is called against possible nodes. | |
4100 | * But it's BUG to call kmalloc() against offline node. | |
4101 | * | |
4102 | * TODO: this routine can waste much memory for nodes which will | |
4103 | * never be onlined. It's better to use memory hotplug callback | |
4104 | * function. | |
4105 | */ | |
41e3355d KH |
4106 | if (!node_state(node, N_NORMAL_MEMORY)) |
4107 | tmp = -1; | |
17295c88 | 4108 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); |
6d12e2d8 KH |
4109 | if (!pn) |
4110 | return 1; | |
1ecaab2b | 4111 | |
1ecaab2b KH |
4112 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
4113 | mz = &pn->zoneinfo[zone]; | |
bea8c150 | 4114 | lruvec_init(&mz->lruvec); |
bb4cc1a8 AM |
4115 | mz->usage_in_excess = 0; |
4116 | mz->on_tree = false; | |
d79154bb | 4117 | mz->memcg = memcg; |
1ecaab2b | 4118 | } |
54f72fe0 | 4119 | memcg->nodeinfo[node] = pn; |
6d12e2d8 KH |
4120 | return 0; |
4121 | } | |
4122 | ||
c0ff4b85 | 4123 | static void free_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) |
1ecaab2b | 4124 | { |
54f72fe0 | 4125 | kfree(memcg->nodeinfo[node]); |
1ecaab2b KH |
4126 | } |
4127 | ||
0b8f73e1 | 4128 | static void mem_cgroup_free(struct mem_cgroup *memcg) |
59927fb9 | 4129 | { |
c8b2a36f | 4130 | int node; |
59927fb9 | 4131 | |
0b8f73e1 | 4132 | memcg_wb_domain_exit(memcg); |
c8b2a36f GC |
4133 | for_each_node(node) |
4134 | free_mem_cgroup_per_zone_info(memcg, node); | |
c8b2a36f | 4135 | free_percpu(memcg->stat); |
8ff69e2c | 4136 | kfree(memcg); |
59927fb9 | 4137 | } |
3afe36b1 | 4138 | |
0b8f73e1 | 4139 | static struct mem_cgroup *mem_cgroup_alloc(void) |
8cdea7c0 | 4140 | { |
d142e3e6 | 4141 | struct mem_cgroup *memcg; |
0b8f73e1 | 4142 | size_t size; |
6d12e2d8 | 4143 | int node; |
8cdea7c0 | 4144 | |
0b8f73e1 JW |
4145 | size = sizeof(struct mem_cgroup); |
4146 | size += nr_node_ids * sizeof(struct mem_cgroup_per_node *); | |
4147 | ||
4148 | memcg = kzalloc(size, GFP_KERNEL); | |
c0ff4b85 | 4149 | if (!memcg) |
0b8f73e1 JW |
4150 | return NULL; |
4151 | ||
4152 | memcg->stat = alloc_percpu(struct mem_cgroup_stat_cpu); | |
4153 | if (!memcg->stat) | |
4154 | goto fail; | |
78fb7466 | 4155 | |
3ed28fa1 | 4156 | for_each_node(node) |
c0ff4b85 | 4157 | if (alloc_mem_cgroup_per_zone_info(memcg, node)) |
0b8f73e1 | 4158 | goto fail; |
f64c3f54 | 4159 | |
0b8f73e1 JW |
4160 | if (memcg_wb_domain_init(memcg, GFP_KERNEL)) |
4161 | goto fail; | |
28dbc4b6 | 4162 | |
f7e1cb6e | 4163 | INIT_WORK(&memcg->high_work, high_work_func); |
d142e3e6 GC |
4164 | memcg->last_scanned_node = MAX_NUMNODES; |
4165 | INIT_LIST_HEAD(&memcg->oom_notify); | |
d142e3e6 GC |
4166 | mutex_init(&memcg->thresholds_lock); |
4167 | spin_lock_init(&memcg->move_lock); | |
70ddf637 | 4168 | vmpressure_init(&memcg->vmpressure); |
fba94807 TH |
4169 | INIT_LIST_HEAD(&memcg->event_list); |
4170 | spin_lock_init(&memcg->event_list_lock); | |
d886f4e4 | 4171 | memcg->socket_pressure = jiffies; |
127424c8 | 4172 | #ifndef CONFIG_SLOB |
900a38f0 | 4173 | memcg->kmemcg_id = -1; |
900a38f0 | 4174 | #endif |
52ebea74 TH |
4175 | #ifdef CONFIG_CGROUP_WRITEBACK |
4176 | INIT_LIST_HEAD(&memcg->cgwb_list); | |
4177 | #endif | |
0b8f73e1 JW |
4178 | return memcg; |
4179 | fail: | |
4180 | mem_cgroup_free(memcg); | |
4181 | return NULL; | |
d142e3e6 GC |
4182 | } |
4183 | ||
0b8f73e1 JW |
4184 | static struct cgroup_subsys_state * __ref |
4185 | mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
d142e3e6 | 4186 | { |
0b8f73e1 JW |
4187 | struct mem_cgroup *parent = mem_cgroup_from_css(parent_css); |
4188 | struct mem_cgroup *memcg; | |
4189 | long error = -ENOMEM; | |
d142e3e6 | 4190 | |
0b8f73e1 JW |
4191 | memcg = mem_cgroup_alloc(); |
4192 | if (!memcg) | |
4193 | return ERR_PTR(error); | |
d142e3e6 | 4194 | |
0b8f73e1 JW |
4195 | memcg->high = PAGE_COUNTER_MAX; |
4196 | memcg->soft_limit = PAGE_COUNTER_MAX; | |
4197 | if (parent) { | |
4198 | memcg->swappiness = mem_cgroup_swappiness(parent); | |
4199 | memcg->oom_kill_disable = parent->oom_kill_disable; | |
4200 | } | |
4201 | if (parent && parent->use_hierarchy) { | |
4202 | memcg->use_hierarchy = true; | |
3e32cb2e JW |
4203 | page_counter_init(&memcg->memory, &parent->memory); |
4204 | page_counter_init(&memcg->memsw, &parent->memsw); | |
4205 | page_counter_init(&memcg->kmem, &parent->kmem); | |
0db15298 | 4206 | page_counter_init(&memcg->tcpmem, &parent->tcpmem); |
18f59ea7 | 4207 | } else { |
3e32cb2e JW |
4208 | page_counter_init(&memcg->memory, NULL); |
4209 | page_counter_init(&memcg->memsw, NULL); | |
4210 | page_counter_init(&memcg->kmem, NULL); | |
0db15298 | 4211 | page_counter_init(&memcg->tcpmem, NULL); |
8c7f6edb TH |
4212 | /* |
4213 | * Deeper hierachy with use_hierarchy == false doesn't make | |
4214 | * much sense so let cgroup subsystem know about this | |
4215 | * unfortunate state in our controller. | |
4216 | */ | |
d142e3e6 | 4217 | if (parent != root_mem_cgroup) |
073219e9 | 4218 | memory_cgrp_subsys.broken_hierarchy = true; |
18f59ea7 | 4219 | } |
d6441637 | 4220 | |
0b8f73e1 JW |
4221 | /* The following stuff does not apply to the root */ |
4222 | if (!parent) { | |
4223 | root_mem_cgroup = memcg; | |
4224 | return &memcg->css; | |
4225 | } | |
4226 | ||
4227 | error = memcg_propagate_kmem(parent, memcg); | |
4228 | if (error) | |
4229 | goto fail; | |
127424c8 | 4230 | |
f7e1cb6e | 4231 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 4232 | static_branch_inc(&memcg_sockets_enabled_key); |
f7e1cb6e | 4233 | |
0b8f73e1 JW |
4234 | return &memcg->css; |
4235 | fail: | |
4236 | mem_cgroup_free(memcg); | |
4237 | return NULL; | |
4238 | } | |
4239 | ||
4240 | static int | |
4241 | mem_cgroup_css_online(struct cgroup_subsys_state *css) | |
4242 | { | |
4243 | if (css->id > MEM_CGROUP_ID_MAX) | |
4244 | return -ENOSPC; | |
2f7dd7a4 JW |
4245 | |
4246 | return 0; | |
8cdea7c0 BS |
4247 | } |
4248 | ||
eb95419b | 4249 | static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) |
df878fb0 | 4250 | { |
eb95419b | 4251 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
3bc942f3 | 4252 | struct mem_cgroup_event *event, *tmp; |
79bd9814 TH |
4253 | |
4254 | /* | |
4255 | * Unregister events and notify userspace. | |
4256 | * Notify userspace about cgroup removing only after rmdir of cgroup | |
4257 | * directory to avoid race between userspace and kernelspace. | |
4258 | */ | |
fba94807 TH |
4259 | spin_lock(&memcg->event_list_lock); |
4260 | list_for_each_entry_safe(event, tmp, &memcg->event_list, list) { | |
79bd9814 TH |
4261 | list_del_init(&event->list); |
4262 | schedule_work(&event->remove); | |
4263 | } | |
fba94807 | 4264 | spin_unlock(&memcg->event_list_lock); |
ec64f515 | 4265 | |
567e9ab2 | 4266 | memcg_offline_kmem(memcg); |
52ebea74 | 4267 | wb_memcg_offline(memcg); |
df878fb0 KH |
4268 | } |
4269 | ||
6df38689 VD |
4270 | static void mem_cgroup_css_released(struct cgroup_subsys_state *css) |
4271 | { | |
4272 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
4273 | ||
4274 | invalidate_reclaim_iterators(memcg); | |
4275 | } | |
4276 | ||
eb95419b | 4277 | static void mem_cgroup_css_free(struct cgroup_subsys_state *css) |
8cdea7c0 | 4278 | { |
eb95419b | 4279 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
c268e994 | 4280 | |
f7e1cb6e | 4281 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) |
ef12947c | 4282 | static_branch_dec(&memcg_sockets_enabled_key); |
127424c8 | 4283 | |
0db15298 | 4284 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_active) |
d55f90bf | 4285 | static_branch_dec(&memcg_sockets_enabled_key); |
3893e302 | 4286 | |
0b8f73e1 JW |
4287 | vmpressure_cleanup(&memcg->vmpressure); |
4288 | cancel_work_sync(&memcg->high_work); | |
4289 | mem_cgroup_remove_from_trees(memcg); | |
d886f4e4 | 4290 | memcg_free_kmem(memcg); |
0b8f73e1 | 4291 | mem_cgroup_free(memcg); |
8cdea7c0 BS |
4292 | } |
4293 | ||
1ced953b TH |
4294 | /** |
4295 | * mem_cgroup_css_reset - reset the states of a mem_cgroup | |
4296 | * @css: the target css | |
4297 | * | |
4298 | * Reset the states of the mem_cgroup associated with @css. This is | |
4299 | * invoked when the userland requests disabling on the default hierarchy | |
4300 | * but the memcg is pinned through dependency. The memcg should stop | |
4301 | * applying policies and should revert to the vanilla state as it may be | |
4302 | * made visible again. | |
4303 | * | |
4304 | * The current implementation only resets the essential configurations. | |
4305 | * This needs to be expanded to cover all the visible parts. | |
4306 | */ | |
4307 | static void mem_cgroup_css_reset(struct cgroup_subsys_state *css) | |
4308 | { | |
4309 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); | |
4310 | ||
3e32cb2e JW |
4311 | mem_cgroup_resize_limit(memcg, PAGE_COUNTER_MAX); |
4312 | mem_cgroup_resize_memsw_limit(memcg, PAGE_COUNTER_MAX); | |
4313 | memcg_update_kmem_limit(memcg, PAGE_COUNTER_MAX); | |
241994ed JW |
4314 | memcg->low = 0; |
4315 | memcg->high = PAGE_COUNTER_MAX; | |
24d404dc | 4316 | memcg->soft_limit = PAGE_COUNTER_MAX; |
2529bb3a | 4317 | memcg_wb_domain_size_changed(memcg); |
1ced953b TH |
4318 | } |
4319 | ||
02491447 | 4320 | #ifdef CONFIG_MMU |
7dc74be0 | 4321 | /* Handlers for move charge at task migration. */ |
854ffa8d | 4322 | static int mem_cgroup_do_precharge(unsigned long count) |
7dc74be0 | 4323 | { |
05b84301 | 4324 | int ret; |
9476db97 | 4325 | |
d0164adc MG |
4326 | /* Try a single bulk charge without reclaim first, kswapd may wake */ |
4327 | ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_DIRECT_RECLAIM, count); | |
9476db97 | 4328 | if (!ret) { |
854ffa8d | 4329 | mc.precharge += count; |
854ffa8d DN |
4330 | return ret; |
4331 | } | |
9476db97 JW |
4332 | |
4333 | /* Try charges one by one with reclaim */ | |
854ffa8d | 4334 | while (count--) { |
00501b53 | 4335 | ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_NORETRY, 1); |
38c5d72f | 4336 | if (ret) |
38c5d72f | 4337 | return ret; |
854ffa8d | 4338 | mc.precharge++; |
9476db97 | 4339 | cond_resched(); |
854ffa8d | 4340 | } |
9476db97 | 4341 | return 0; |
4ffef5fe DN |
4342 | } |
4343 | ||
4344 | /** | |
8d32ff84 | 4345 | * get_mctgt_type - get target type of moving charge |
4ffef5fe DN |
4346 | * @vma: the vma the pte to be checked belongs |
4347 | * @addr: the address corresponding to the pte to be checked | |
4348 | * @ptent: the pte to be checked | |
02491447 | 4349 | * @target: the pointer the target page or swap ent will be stored(can be NULL) |
4ffef5fe DN |
4350 | * |
4351 | * Returns | |
4352 | * 0(MC_TARGET_NONE): if the pte is not a target for move charge. | |
4353 | * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for | |
4354 | * move charge. if @target is not NULL, the page is stored in target->page | |
4355 | * with extra refcnt got(Callers should handle it). | |
02491447 DN |
4356 | * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a |
4357 | * target for charge migration. if @target is not NULL, the entry is stored | |
4358 | * in target->ent. | |
4ffef5fe DN |
4359 | * |
4360 | * Called with pte lock held. | |
4361 | */ | |
4ffef5fe DN |
4362 | union mc_target { |
4363 | struct page *page; | |
02491447 | 4364 | swp_entry_t ent; |
4ffef5fe DN |
4365 | }; |
4366 | ||
4ffef5fe | 4367 | enum mc_target_type { |
8d32ff84 | 4368 | MC_TARGET_NONE = 0, |
4ffef5fe | 4369 | MC_TARGET_PAGE, |
02491447 | 4370 | MC_TARGET_SWAP, |
4ffef5fe DN |
4371 | }; |
4372 | ||
90254a65 DN |
4373 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
4374 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 4375 | { |
90254a65 | 4376 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 4377 | |
90254a65 DN |
4378 | if (!page || !page_mapped(page)) |
4379 | return NULL; | |
4380 | if (PageAnon(page)) { | |
1dfab5ab | 4381 | if (!(mc.flags & MOVE_ANON)) |
90254a65 | 4382 | return NULL; |
1dfab5ab JW |
4383 | } else { |
4384 | if (!(mc.flags & MOVE_FILE)) | |
4385 | return NULL; | |
4386 | } | |
90254a65 DN |
4387 | if (!get_page_unless_zero(page)) |
4388 | return NULL; | |
4389 | ||
4390 | return page; | |
4391 | } | |
4392 | ||
4b91355e | 4393 | #ifdef CONFIG_SWAP |
90254a65 DN |
4394 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, |
4395 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
4396 | { | |
90254a65 DN |
4397 | struct page *page = NULL; |
4398 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
4399 | ||
1dfab5ab | 4400 | if (!(mc.flags & MOVE_ANON) || non_swap_entry(ent)) |
90254a65 | 4401 | return NULL; |
4b91355e KH |
4402 | /* |
4403 | * Because lookup_swap_cache() updates some statistics counter, | |
4404 | * we call find_get_page() with swapper_space directly. | |
4405 | */ | |
33806f06 | 4406 | page = find_get_page(swap_address_space(ent), ent.val); |
7941d214 | 4407 | if (do_memsw_account()) |
90254a65 DN |
4408 | entry->val = ent.val; |
4409 | ||
4410 | return page; | |
4411 | } | |
4b91355e KH |
4412 | #else |
4413 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
4414 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
4415 | { | |
4416 | return NULL; | |
4417 | } | |
4418 | #endif | |
90254a65 | 4419 | |
87946a72 DN |
4420 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
4421 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
4422 | { | |
4423 | struct page *page = NULL; | |
87946a72 DN |
4424 | struct address_space *mapping; |
4425 | pgoff_t pgoff; | |
4426 | ||
4427 | if (!vma->vm_file) /* anonymous vma */ | |
4428 | return NULL; | |
1dfab5ab | 4429 | if (!(mc.flags & MOVE_FILE)) |
87946a72 DN |
4430 | return NULL; |
4431 | ||
87946a72 | 4432 | mapping = vma->vm_file->f_mapping; |
0661a336 | 4433 | pgoff = linear_page_index(vma, addr); |
87946a72 DN |
4434 | |
4435 | /* page is moved even if it's not RSS of this task(page-faulted). */ | |
aa3b1895 HD |
4436 | #ifdef CONFIG_SWAP |
4437 | /* shmem/tmpfs may report page out on swap: account for that too. */ | |
139b6a6f JW |
4438 | if (shmem_mapping(mapping)) { |
4439 | page = find_get_entry(mapping, pgoff); | |
4440 | if (radix_tree_exceptional_entry(page)) { | |
4441 | swp_entry_t swp = radix_to_swp_entry(page); | |
7941d214 | 4442 | if (do_memsw_account()) |
139b6a6f JW |
4443 | *entry = swp; |
4444 | page = find_get_page(swap_address_space(swp), swp.val); | |
4445 | } | |
4446 | } else | |
4447 | page = find_get_page(mapping, pgoff); | |
4448 | #else | |
4449 | page = find_get_page(mapping, pgoff); | |
aa3b1895 | 4450 | #endif |
87946a72 DN |
4451 | return page; |
4452 | } | |
4453 | ||
b1b0deab CG |
4454 | /** |
4455 | * mem_cgroup_move_account - move account of the page | |
4456 | * @page: the page | |
4457 | * @nr_pages: number of regular pages (>1 for huge pages) | |
4458 | * @from: mem_cgroup which the page is moved from. | |
4459 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
4460 | * | |
3ac808fd | 4461 | * The caller must make sure the page is not on LRU (isolate_page() is useful.) |
b1b0deab CG |
4462 | * |
4463 | * This function doesn't do "charge" to new cgroup and doesn't do "uncharge" | |
4464 | * from old cgroup. | |
4465 | */ | |
4466 | static int mem_cgroup_move_account(struct page *page, | |
f627c2f5 | 4467 | bool compound, |
b1b0deab CG |
4468 | struct mem_cgroup *from, |
4469 | struct mem_cgroup *to) | |
4470 | { | |
4471 | unsigned long flags; | |
f627c2f5 | 4472 | unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1; |
b1b0deab | 4473 | int ret; |
c4843a75 | 4474 | bool anon; |
b1b0deab CG |
4475 | |
4476 | VM_BUG_ON(from == to); | |
4477 | VM_BUG_ON_PAGE(PageLRU(page), page); | |
f627c2f5 | 4478 | VM_BUG_ON(compound && !PageTransHuge(page)); |
b1b0deab CG |
4479 | |
4480 | /* | |
45637bab HD |
4481 | * Prevent mem_cgroup_replace_page() from looking at |
4482 | * page->mem_cgroup of its source page while we change it. | |
b1b0deab | 4483 | */ |
f627c2f5 | 4484 | ret = -EBUSY; |
b1b0deab CG |
4485 | if (!trylock_page(page)) |
4486 | goto out; | |
4487 | ||
4488 | ret = -EINVAL; | |
4489 | if (page->mem_cgroup != from) | |
4490 | goto out_unlock; | |
4491 | ||
c4843a75 GT |
4492 | anon = PageAnon(page); |
4493 | ||
b1b0deab CG |
4494 | spin_lock_irqsave(&from->move_lock, flags); |
4495 | ||
c4843a75 | 4496 | if (!anon && page_mapped(page)) { |
b1b0deab CG |
4497 | __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED], |
4498 | nr_pages); | |
4499 | __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED], | |
4500 | nr_pages); | |
4501 | } | |
4502 | ||
c4843a75 GT |
4503 | /* |
4504 | * move_lock grabbed above and caller set from->moving_account, so | |
4505 | * mem_cgroup_update_page_stat() will serialize updates to PageDirty. | |
4506 | * So mapping should be stable for dirty pages. | |
4507 | */ | |
4508 | if (!anon && PageDirty(page)) { | |
4509 | struct address_space *mapping = page_mapping(page); | |
4510 | ||
4511 | if (mapping_cap_account_dirty(mapping)) { | |
4512 | __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_DIRTY], | |
4513 | nr_pages); | |
4514 | __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_DIRTY], | |
4515 | nr_pages); | |
4516 | } | |
4517 | } | |
4518 | ||
b1b0deab CG |
4519 | if (PageWriteback(page)) { |
4520 | __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_WRITEBACK], | |
4521 | nr_pages); | |
4522 | __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_WRITEBACK], | |
4523 | nr_pages); | |
4524 | } | |
4525 | ||
4526 | /* | |
4527 | * It is safe to change page->mem_cgroup here because the page | |
4528 | * is referenced, charged, and isolated - we can't race with | |
4529 | * uncharging, charging, migration, or LRU putback. | |
4530 | */ | |
4531 | ||
4532 | /* caller should have done css_get */ | |
4533 | page->mem_cgroup = to; | |
4534 | spin_unlock_irqrestore(&from->move_lock, flags); | |
4535 | ||
4536 | ret = 0; | |
4537 | ||
4538 | local_irq_disable(); | |
f627c2f5 | 4539 | mem_cgroup_charge_statistics(to, page, compound, nr_pages); |
b1b0deab | 4540 | memcg_check_events(to, page); |
f627c2f5 | 4541 | mem_cgroup_charge_statistics(from, page, compound, -nr_pages); |
b1b0deab CG |
4542 | memcg_check_events(from, page); |
4543 | local_irq_enable(); | |
4544 | out_unlock: | |
4545 | unlock_page(page); | |
4546 | out: | |
4547 | return ret; | |
4548 | } | |
4549 | ||
8d32ff84 | 4550 | static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, |
90254a65 DN |
4551 | unsigned long addr, pte_t ptent, union mc_target *target) |
4552 | { | |
4553 | struct page *page = NULL; | |
8d32ff84 | 4554 | enum mc_target_type ret = MC_TARGET_NONE; |
90254a65 DN |
4555 | swp_entry_t ent = { .val = 0 }; |
4556 | ||
4557 | if (pte_present(ptent)) | |
4558 | page = mc_handle_present_pte(vma, addr, ptent); | |
4559 | else if (is_swap_pte(ptent)) | |
4560 | page = mc_handle_swap_pte(vma, addr, ptent, &ent); | |
0661a336 | 4561 | else if (pte_none(ptent)) |
87946a72 | 4562 | page = mc_handle_file_pte(vma, addr, ptent, &ent); |
90254a65 DN |
4563 | |
4564 | if (!page && !ent.val) | |
8d32ff84 | 4565 | return ret; |
02491447 | 4566 | if (page) { |
02491447 | 4567 | /* |
0a31bc97 | 4568 | * Do only loose check w/o serialization. |
1306a85a | 4569 | * mem_cgroup_move_account() checks the page is valid or |
0a31bc97 | 4570 | * not under LRU exclusion. |
02491447 | 4571 | */ |
1306a85a | 4572 | if (page->mem_cgroup == mc.from) { |
02491447 DN |
4573 | ret = MC_TARGET_PAGE; |
4574 | if (target) | |
4575 | target->page = page; | |
4576 | } | |
4577 | if (!ret || !target) | |
4578 | put_page(page); | |
4579 | } | |
90254a65 DN |
4580 | /* There is a swap entry and a page doesn't exist or isn't charged */ |
4581 | if (ent.val && !ret && | |
34c00c31 | 4582 | mem_cgroup_id(mc.from) == lookup_swap_cgroup_id(ent)) { |
7f0f1546 KH |
4583 | ret = MC_TARGET_SWAP; |
4584 | if (target) | |
4585 | target->ent = ent; | |
4ffef5fe | 4586 | } |
4ffef5fe DN |
4587 | return ret; |
4588 | } | |
4589 | ||
12724850 NH |
4590 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
4591 | /* | |
4592 | * We don't consider swapping or file mapped pages because THP does not | |
4593 | * support them for now. | |
4594 | * Caller should make sure that pmd_trans_huge(pmd) is true. | |
4595 | */ | |
4596 | static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
4597 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
4598 | { | |
4599 | struct page *page = NULL; | |
12724850 NH |
4600 | enum mc_target_type ret = MC_TARGET_NONE; |
4601 | ||
4602 | page = pmd_page(pmd); | |
309381fe | 4603 | VM_BUG_ON_PAGE(!page || !PageHead(page), page); |
1dfab5ab | 4604 | if (!(mc.flags & MOVE_ANON)) |
12724850 | 4605 | return ret; |
1306a85a | 4606 | if (page->mem_cgroup == mc.from) { |
12724850 NH |
4607 | ret = MC_TARGET_PAGE; |
4608 | if (target) { | |
4609 | get_page(page); | |
4610 | target->page = page; | |
4611 | } | |
4612 | } | |
4613 | return ret; | |
4614 | } | |
4615 | #else | |
4616 | static inline enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
4617 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
4618 | { | |
4619 | return MC_TARGET_NONE; | |
4620 | } | |
4621 | #endif | |
4622 | ||
4ffef5fe DN |
4623 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, |
4624 | unsigned long addr, unsigned long end, | |
4625 | struct mm_walk *walk) | |
4626 | { | |
26bcd64a | 4627 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
4628 | pte_t *pte; |
4629 | spinlock_t *ptl; | |
4630 | ||
4b471e88 | 4631 | if (pmd_trans_huge_lock(pmd, vma, &ptl)) { |
12724850 NH |
4632 | if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE) |
4633 | mc.precharge += HPAGE_PMD_NR; | |
bf929152 | 4634 | spin_unlock(ptl); |
1a5a9906 | 4635 | return 0; |
12724850 | 4636 | } |
03319327 | 4637 | |
45f83cef AA |
4638 | if (pmd_trans_unstable(pmd)) |
4639 | return 0; | |
4ffef5fe DN |
4640 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
4641 | for (; addr != end; pte++, addr += PAGE_SIZE) | |
8d32ff84 | 4642 | if (get_mctgt_type(vma, addr, *pte, NULL)) |
4ffef5fe DN |
4643 | mc.precharge++; /* increment precharge temporarily */ |
4644 | pte_unmap_unlock(pte - 1, ptl); | |
4645 | cond_resched(); | |
4646 | ||
7dc74be0 DN |
4647 | return 0; |
4648 | } | |
4649 | ||
4ffef5fe DN |
4650 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
4651 | { | |
4652 | unsigned long precharge; | |
4ffef5fe | 4653 | |
26bcd64a NH |
4654 | struct mm_walk mem_cgroup_count_precharge_walk = { |
4655 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
4656 | .mm = mm, | |
4657 | }; | |
dfe076b0 | 4658 | down_read(&mm->mmap_sem); |
26bcd64a | 4659 | walk_page_range(0, ~0UL, &mem_cgroup_count_precharge_walk); |
dfe076b0 | 4660 | up_read(&mm->mmap_sem); |
4ffef5fe DN |
4661 | |
4662 | precharge = mc.precharge; | |
4663 | mc.precharge = 0; | |
4664 | ||
4665 | return precharge; | |
4666 | } | |
4667 | ||
4ffef5fe DN |
4668 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
4669 | { | |
dfe076b0 DN |
4670 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
4671 | ||
4672 | VM_BUG_ON(mc.moving_task); | |
4673 | mc.moving_task = current; | |
4674 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
4675 | } |
4676 | ||
dfe076b0 DN |
4677 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
4678 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 4679 | { |
2bd9bb20 KH |
4680 | struct mem_cgroup *from = mc.from; |
4681 | struct mem_cgroup *to = mc.to; | |
4682 | ||
4ffef5fe | 4683 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d | 4684 | if (mc.precharge) { |
00501b53 | 4685 | cancel_charge(mc.to, mc.precharge); |
854ffa8d DN |
4686 | mc.precharge = 0; |
4687 | } | |
4688 | /* | |
4689 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
4690 | * we must uncharge here. | |
4691 | */ | |
4692 | if (mc.moved_charge) { | |
00501b53 | 4693 | cancel_charge(mc.from, mc.moved_charge); |
854ffa8d | 4694 | mc.moved_charge = 0; |
4ffef5fe | 4695 | } |
483c30b5 DN |
4696 | /* we must fixup refcnts and charges */ |
4697 | if (mc.moved_swap) { | |
483c30b5 | 4698 | /* uncharge swap account from the old cgroup */ |
ce00a967 | 4699 | if (!mem_cgroup_is_root(mc.from)) |
3e32cb2e | 4700 | page_counter_uncharge(&mc.from->memsw, mc.moved_swap); |
483c30b5 | 4701 | |
05b84301 | 4702 | /* |
3e32cb2e JW |
4703 | * we charged both to->memory and to->memsw, so we |
4704 | * should uncharge to->memory. | |
05b84301 | 4705 | */ |
ce00a967 | 4706 | if (!mem_cgroup_is_root(mc.to)) |
3e32cb2e JW |
4707 | page_counter_uncharge(&mc.to->memory, mc.moved_swap); |
4708 | ||
e8ea14cc | 4709 | css_put_many(&mc.from->css, mc.moved_swap); |
3e32cb2e | 4710 | |
4050377b | 4711 | /* we've already done css_get(mc.to) */ |
483c30b5 DN |
4712 | mc.moved_swap = 0; |
4713 | } | |
dfe076b0 DN |
4714 | memcg_oom_recover(from); |
4715 | memcg_oom_recover(to); | |
4716 | wake_up_all(&mc.waitq); | |
4717 | } | |
4718 | ||
4719 | static void mem_cgroup_clear_mc(void) | |
4720 | { | |
dfe076b0 DN |
4721 | /* |
4722 | * we must clear moving_task before waking up waiters at the end of | |
4723 | * task migration. | |
4724 | */ | |
4725 | mc.moving_task = NULL; | |
4726 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 4727 | spin_lock(&mc.lock); |
4ffef5fe DN |
4728 | mc.from = NULL; |
4729 | mc.to = NULL; | |
2bd9bb20 | 4730 | spin_unlock(&mc.lock); |
4ffef5fe DN |
4731 | } |
4732 | ||
1f7dd3e5 | 4733 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
7dc74be0 | 4734 | { |
1f7dd3e5 | 4735 | struct cgroup_subsys_state *css; |
eed67d75 | 4736 | struct mem_cgroup *memcg = NULL; /* unneeded init to make gcc happy */ |
9f2115f9 | 4737 | struct mem_cgroup *from; |
4530eddb | 4738 | struct task_struct *leader, *p; |
9f2115f9 | 4739 | struct mm_struct *mm; |
1dfab5ab | 4740 | unsigned long move_flags; |
9f2115f9 | 4741 | int ret = 0; |
7dc74be0 | 4742 | |
1f7dd3e5 TH |
4743 | /* charge immigration isn't supported on the default hierarchy */ |
4744 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
9f2115f9 TH |
4745 | return 0; |
4746 | ||
4530eddb TH |
4747 | /* |
4748 | * Multi-process migrations only happen on the default hierarchy | |
4749 | * where charge immigration is not used. Perform charge | |
4750 | * immigration if @tset contains a leader and whine if there are | |
4751 | * multiple. | |
4752 | */ | |
4753 | p = NULL; | |
1f7dd3e5 | 4754 | cgroup_taskset_for_each_leader(leader, css, tset) { |
4530eddb TH |
4755 | WARN_ON_ONCE(p); |
4756 | p = leader; | |
1f7dd3e5 | 4757 | memcg = mem_cgroup_from_css(css); |
4530eddb TH |
4758 | } |
4759 | if (!p) | |
4760 | return 0; | |
4761 | ||
1f7dd3e5 TH |
4762 | /* |
4763 | * We are now commited to this value whatever it is. Changes in this | |
4764 | * tunable will only affect upcoming migrations, not the current one. | |
4765 | * So we need to save it, and keep it going. | |
4766 | */ | |
4767 | move_flags = READ_ONCE(memcg->move_charge_at_immigrate); | |
4768 | if (!move_flags) | |
4769 | return 0; | |
4770 | ||
9f2115f9 TH |
4771 | from = mem_cgroup_from_task(p); |
4772 | ||
4773 | VM_BUG_ON(from == memcg); | |
4774 | ||
4775 | mm = get_task_mm(p); | |
4776 | if (!mm) | |
4777 | return 0; | |
4778 | /* We move charges only when we move a owner of the mm */ | |
4779 | if (mm->owner == p) { | |
4780 | VM_BUG_ON(mc.from); | |
4781 | VM_BUG_ON(mc.to); | |
4782 | VM_BUG_ON(mc.precharge); | |
4783 | VM_BUG_ON(mc.moved_charge); | |
4784 | VM_BUG_ON(mc.moved_swap); | |
4785 | ||
4786 | spin_lock(&mc.lock); | |
4787 | mc.from = from; | |
4788 | mc.to = memcg; | |
4789 | mc.flags = move_flags; | |
4790 | spin_unlock(&mc.lock); | |
4791 | /* We set mc.moving_task later */ | |
4792 | ||
4793 | ret = mem_cgroup_precharge_mc(mm); | |
4794 | if (ret) | |
4795 | mem_cgroup_clear_mc(); | |
7dc74be0 | 4796 | } |
9f2115f9 | 4797 | mmput(mm); |
7dc74be0 DN |
4798 | return ret; |
4799 | } | |
4800 | ||
1f7dd3e5 | 4801 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
7dc74be0 | 4802 | { |
4e2f245d JW |
4803 | if (mc.to) |
4804 | mem_cgroup_clear_mc(); | |
7dc74be0 DN |
4805 | } |
4806 | ||
4ffef5fe DN |
4807 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
4808 | unsigned long addr, unsigned long end, | |
4809 | struct mm_walk *walk) | |
7dc74be0 | 4810 | { |
4ffef5fe | 4811 | int ret = 0; |
26bcd64a | 4812 | struct vm_area_struct *vma = walk->vma; |
4ffef5fe DN |
4813 | pte_t *pte; |
4814 | spinlock_t *ptl; | |
12724850 NH |
4815 | enum mc_target_type target_type; |
4816 | union mc_target target; | |
4817 | struct page *page; | |
4ffef5fe | 4818 | |
4b471e88 | 4819 | if (pmd_trans_huge_lock(pmd, vma, &ptl)) { |
62ade86a | 4820 | if (mc.precharge < HPAGE_PMD_NR) { |
bf929152 | 4821 | spin_unlock(ptl); |
12724850 NH |
4822 | return 0; |
4823 | } | |
4824 | target_type = get_mctgt_type_thp(vma, addr, *pmd, &target); | |
4825 | if (target_type == MC_TARGET_PAGE) { | |
4826 | page = target.page; | |
4827 | if (!isolate_lru_page(page)) { | |
f627c2f5 | 4828 | if (!mem_cgroup_move_account(page, true, |
1306a85a | 4829 | mc.from, mc.to)) { |
12724850 NH |
4830 | mc.precharge -= HPAGE_PMD_NR; |
4831 | mc.moved_charge += HPAGE_PMD_NR; | |
4832 | } | |
4833 | putback_lru_page(page); | |
4834 | } | |
4835 | put_page(page); | |
4836 | } | |
bf929152 | 4837 | spin_unlock(ptl); |
1a5a9906 | 4838 | return 0; |
12724850 NH |
4839 | } |
4840 | ||
45f83cef AA |
4841 | if (pmd_trans_unstable(pmd)) |
4842 | return 0; | |
4ffef5fe DN |
4843 | retry: |
4844 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
4845 | for (; addr != end; addr += PAGE_SIZE) { | |
4846 | pte_t ptent = *(pte++); | |
02491447 | 4847 | swp_entry_t ent; |
4ffef5fe DN |
4848 | |
4849 | if (!mc.precharge) | |
4850 | break; | |
4851 | ||
8d32ff84 | 4852 | switch (get_mctgt_type(vma, addr, ptent, &target)) { |
4ffef5fe DN |
4853 | case MC_TARGET_PAGE: |
4854 | page = target.page; | |
53f9263b KS |
4855 | /* |
4856 | * We can have a part of the split pmd here. Moving it | |
4857 | * can be done but it would be too convoluted so simply | |
4858 | * ignore such a partial THP and keep it in original | |
4859 | * memcg. There should be somebody mapping the head. | |
4860 | */ | |
4861 | if (PageTransCompound(page)) | |
4862 | goto put; | |
4ffef5fe DN |
4863 | if (isolate_lru_page(page)) |
4864 | goto put; | |
f627c2f5 KS |
4865 | if (!mem_cgroup_move_account(page, false, |
4866 | mc.from, mc.to)) { | |
4ffef5fe | 4867 | mc.precharge--; |
854ffa8d DN |
4868 | /* we uncharge from mc.from later. */ |
4869 | mc.moved_charge++; | |
4ffef5fe DN |
4870 | } |
4871 | putback_lru_page(page); | |
8d32ff84 | 4872 | put: /* get_mctgt_type() gets the page */ |
4ffef5fe DN |
4873 | put_page(page); |
4874 | break; | |
02491447 DN |
4875 | case MC_TARGET_SWAP: |
4876 | ent = target.ent; | |
e91cbb42 | 4877 | if (!mem_cgroup_move_swap_account(ent, mc.from, mc.to)) { |
02491447 | 4878 | mc.precharge--; |
483c30b5 DN |
4879 | /* we fixup refcnts and charges later. */ |
4880 | mc.moved_swap++; | |
4881 | } | |
02491447 | 4882 | break; |
4ffef5fe DN |
4883 | default: |
4884 | break; | |
4885 | } | |
4886 | } | |
4887 | pte_unmap_unlock(pte - 1, ptl); | |
4888 | cond_resched(); | |
4889 | ||
4890 | if (addr != end) { | |
4891 | /* | |
4892 | * We have consumed all precharges we got in can_attach(). | |
4893 | * We try charge one by one, but don't do any additional | |
4894 | * charges to mc.to if we have failed in charge once in attach() | |
4895 | * phase. | |
4896 | */ | |
854ffa8d | 4897 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
4898 | if (!ret) |
4899 | goto retry; | |
4900 | } | |
4901 | ||
4902 | return ret; | |
4903 | } | |
4904 | ||
4905 | static void mem_cgroup_move_charge(struct mm_struct *mm) | |
4906 | { | |
26bcd64a NH |
4907 | struct mm_walk mem_cgroup_move_charge_walk = { |
4908 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
4909 | .mm = mm, | |
4910 | }; | |
4ffef5fe DN |
4911 | |
4912 | lru_add_drain_all(); | |
312722cb JW |
4913 | /* |
4914 | * Signal mem_cgroup_begin_page_stat() to take the memcg's | |
4915 | * move_lock while we're moving its pages to another memcg. | |
4916 | * Then wait for already started RCU-only updates to finish. | |
4917 | */ | |
4918 | atomic_inc(&mc.from->moving_account); | |
4919 | synchronize_rcu(); | |
dfe076b0 DN |
4920 | retry: |
4921 | if (unlikely(!down_read_trylock(&mm->mmap_sem))) { | |
4922 | /* | |
4923 | * Someone who are holding the mmap_sem might be waiting in | |
4924 | * waitq. So we cancel all extra charges, wake up all waiters, | |
4925 | * and retry. Because we cancel precharges, we might not be able | |
4926 | * to move enough charges, but moving charge is a best-effort | |
4927 | * feature anyway, so it wouldn't be a big problem. | |
4928 | */ | |
4929 | __mem_cgroup_clear_mc(); | |
4930 | cond_resched(); | |
4931 | goto retry; | |
4932 | } | |
26bcd64a NH |
4933 | /* |
4934 | * When we have consumed all precharges and failed in doing | |
4935 | * additional charge, the page walk just aborts. | |
4936 | */ | |
4937 | walk_page_range(0, ~0UL, &mem_cgroup_move_charge_walk); | |
dfe076b0 | 4938 | up_read(&mm->mmap_sem); |
312722cb | 4939 | atomic_dec(&mc.from->moving_account); |
7dc74be0 DN |
4940 | } |
4941 | ||
1f7dd3e5 | 4942 | static void mem_cgroup_move_task(struct cgroup_taskset *tset) |
67e465a7 | 4943 | { |
1f7dd3e5 TH |
4944 | struct cgroup_subsys_state *css; |
4945 | struct task_struct *p = cgroup_taskset_first(tset, &css); | |
a433658c | 4946 | struct mm_struct *mm = get_task_mm(p); |
dfe076b0 | 4947 | |
dfe076b0 | 4948 | if (mm) { |
a433658c KM |
4949 | if (mc.to) |
4950 | mem_cgroup_move_charge(mm); | |
dfe076b0 DN |
4951 | mmput(mm); |
4952 | } | |
a433658c KM |
4953 | if (mc.to) |
4954 | mem_cgroup_clear_mc(); | |
67e465a7 | 4955 | } |
5cfb80a7 | 4956 | #else /* !CONFIG_MMU */ |
1f7dd3e5 | 4957 | static int mem_cgroup_can_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
4958 | { |
4959 | return 0; | |
4960 | } | |
1f7dd3e5 | 4961 | static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset) |
5cfb80a7 DN |
4962 | { |
4963 | } | |
1f7dd3e5 | 4964 | static void mem_cgroup_move_task(struct cgroup_taskset *tset) |
5cfb80a7 DN |
4965 | { |
4966 | } | |
4967 | #endif | |
67e465a7 | 4968 | |
f00baae7 TH |
4969 | /* |
4970 | * Cgroup retains root cgroups across [un]mount cycles making it necessary | |
aa6ec29b TH |
4971 | * to verify whether we're attached to the default hierarchy on each mount |
4972 | * attempt. | |
f00baae7 | 4973 | */ |
eb95419b | 4974 | static void mem_cgroup_bind(struct cgroup_subsys_state *root_css) |
f00baae7 TH |
4975 | { |
4976 | /* | |
aa6ec29b | 4977 | * use_hierarchy is forced on the default hierarchy. cgroup core |
f00baae7 TH |
4978 | * guarantees that @root doesn't have any children, so turning it |
4979 | * on for the root memcg is enough. | |
4980 | */ | |
9e10a130 | 4981 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) |
7feee590 VD |
4982 | root_mem_cgroup->use_hierarchy = true; |
4983 | else | |
4984 | root_mem_cgroup->use_hierarchy = false; | |
f00baae7 TH |
4985 | } |
4986 | ||
241994ed JW |
4987 | static u64 memory_current_read(struct cgroup_subsys_state *css, |
4988 | struct cftype *cft) | |
4989 | { | |
f5fc3c5d JW |
4990 | struct mem_cgroup *memcg = mem_cgroup_from_css(css); |
4991 | ||
4992 | return (u64)page_counter_read(&memcg->memory) * PAGE_SIZE; | |
241994ed JW |
4993 | } |
4994 | ||
4995 | static int memory_low_show(struct seq_file *m, void *v) | |
4996 | { | |
4997 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); | |
4db0c3c2 | 4998 | unsigned long low = READ_ONCE(memcg->low); |
241994ed JW |
4999 | |
5000 | if (low == PAGE_COUNTER_MAX) | |
d2973697 | 5001 | seq_puts(m, "max\n"); |
241994ed JW |
5002 | else |
5003 | seq_printf(m, "%llu\n", (u64)low * PAGE_SIZE); | |
5004 | ||
5005 | return 0; | |
5006 | } | |
5007 | ||
5008 | static ssize_t memory_low_write(struct kernfs_open_file *of, | |
5009 | char *buf, size_t nbytes, loff_t off) | |
5010 | { | |
5011 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
5012 | unsigned long low; | |
5013 | int err; | |
5014 | ||
5015 | buf = strstrip(buf); | |
d2973697 | 5016 | err = page_counter_memparse(buf, "max", &low); |
241994ed JW |
5017 | if (err) |
5018 | return err; | |
5019 | ||
5020 | memcg->low = low; | |
5021 | ||
5022 | return nbytes; | |
5023 | } | |
5024 | ||
5025 | static int memory_high_show(struct seq_file *m, void *v) | |
5026 | { | |
5027 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); | |
4db0c3c2 | 5028 | unsigned long high = READ_ONCE(memcg->high); |
241994ed JW |
5029 | |
5030 | if (high == PAGE_COUNTER_MAX) | |
d2973697 | 5031 | seq_puts(m, "max\n"); |
241994ed JW |
5032 | else |
5033 | seq_printf(m, "%llu\n", (u64)high * PAGE_SIZE); | |
5034 | ||
5035 | return 0; | |
5036 | } | |
5037 | ||
5038 | static ssize_t memory_high_write(struct kernfs_open_file *of, | |
5039 | char *buf, size_t nbytes, loff_t off) | |
5040 | { | |
5041 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
5042 | unsigned long high; | |
5043 | int err; | |
5044 | ||
5045 | buf = strstrip(buf); | |
d2973697 | 5046 | err = page_counter_memparse(buf, "max", &high); |
241994ed JW |
5047 | if (err) |
5048 | return err; | |
5049 | ||
5050 | memcg->high = high; | |
5051 | ||
2529bb3a | 5052 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
5053 | return nbytes; |
5054 | } | |
5055 | ||
5056 | static int memory_max_show(struct seq_file *m, void *v) | |
5057 | { | |
5058 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); | |
4db0c3c2 | 5059 | unsigned long max = READ_ONCE(memcg->memory.limit); |
241994ed JW |
5060 | |
5061 | if (max == PAGE_COUNTER_MAX) | |
d2973697 | 5062 | seq_puts(m, "max\n"); |
241994ed JW |
5063 | else |
5064 | seq_printf(m, "%llu\n", (u64)max * PAGE_SIZE); | |
5065 | ||
5066 | return 0; | |
5067 | } | |
5068 | ||
5069 | static ssize_t memory_max_write(struct kernfs_open_file *of, | |
5070 | char *buf, size_t nbytes, loff_t off) | |
5071 | { | |
5072 | struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); | |
5073 | unsigned long max; | |
5074 | int err; | |
5075 | ||
5076 | buf = strstrip(buf); | |
d2973697 | 5077 | err = page_counter_memparse(buf, "max", &max); |
241994ed JW |
5078 | if (err) |
5079 | return err; | |
5080 | ||
5081 | err = mem_cgroup_resize_limit(memcg, max); | |
5082 | if (err) | |
5083 | return err; | |
5084 | ||
2529bb3a | 5085 | memcg_wb_domain_size_changed(memcg); |
241994ed JW |
5086 | return nbytes; |
5087 | } | |
5088 | ||
5089 | static int memory_events_show(struct seq_file *m, void *v) | |
5090 | { | |
5091 | struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); | |
5092 | ||
5093 | seq_printf(m, "low %lu\n", mem_cgroup_read_events(memcg, MEMCG_LOW)); | |
5094 | seq_printf(m, "high %lu\n", mem_cgroup_read_events(memcg, MEMCG_HIGH)); | |
5095 | seq_printf(m, "max %lu\n", mem_cgroup_read_events(memcg, MEMCG_MAX)); | |
5096 | seq_printf(m, "oom %lu\n", mem_cgroup_read_events(memcg, MEMCG_OOM)); | |
5097 | ||
5098 | return 0; | |
5099 | } | |
5100 | ||
5101 | static struct cftype memory_files[] = { | |
5102 | { | |
5103 | .name = "current", | |
f5fc3c5d | 5104 | .flags = CFTYPE_NOT_ON_ROOT, |
241994ed JW |
5105 | .read_u64 = memory_current_read, |
5106 | }, | |
5107 | { | |
5108 | .name = "low", | |
5109 | .flags = CFTYPE_NOT_ON_ROOT, | |
5110 | .seq_show = memory_low_show, | |
5111 | .write = memory_low_write, | |
5112 | }, | |
5113 | { | |
5114 | .name = "high", | |
5115 | .flags = CFTYPE_NOT_ON_ROOT, | |
5116 | .seq_show = memory_high_show, | |
5117 | .write = memory_high_write, | |
5118 | }, | |
5119 | { | |
5120 | .name = "max", | |
5121 | .flags = CFTYPE_NOT_ON_ROOT, | |
5122 | .seq_show = memory_max_show, | |
5123 | .write = memory_max_write, | |
5124 | }, | |
5125 | { | |
5126 | .name = "events", | |
5127 | .flags = CFTYPE_NOT_ON_ROOT, | |
472912a2 | 5128 | .file_offset = offsetof(struct mem_cgroup, events_file), |
241994ed JW |
5129 | .seq_show = memory_events_show, |
5130 | }, | |
5131 | { } /* terminate */ | |
5132 | }; | |
5133 | ||
073219e9 | 5134 | struct cgroup_subsys memory_cgrp_subsys = { |
92fb9748 | 5135 | .css_alloc = mem_cgroup_css_alloc, |
d142e3e6 | 5136 | .css_online = mem_cgroup_css_online, |
92fb9748 | 5137 | .css_offline = mem_cgroup_css_offline, |
6df38689 | 5138 | .css_released = mem_cgroup_css_released, |
92fb9748 | 5139 | .css_free = mem_cgroup_css_free, |
1ced953b | 5140 | .css_reset = mem_cgroup_css_reset, |
7dc74be0 DN |
5141 | .can_attach = mem_cgroup_can_attach, |
5142 | .cancel_attach = mem_cgroup_cancel_attach, | |
67e465a7 | 5143 | .attach = mem_cgroup_move_task, |
f00baae7 | 5144 | .bind = mem_cgroup_bind, |
241994ed JW |
5145 | .dfl_cftypes = memory_files, |
5146 | .legacy_cftypes = mem_cgroup_legacy_files, | |
6d12e2d8 | 5147 | .early_init = 0, |
8cdea7c0 | 5148 | }; |
c077719b | 5149 | |
241994ed JW |
5150 | /** |
5151 | * mem_cgroup_low - check if memory consumption is below the normal range | |
5152 | * @root: the highest ancestor to consider | |
5153 | * @memcg: the memory cgroup to check | |
5154 | * | |
5155 | * Returns %true if memory consumption of @memcg, and that of all | |
5156 | * configurable ancestors up to @root, is below the normal range. | |
5157 | */ | |
5158 | bool mem_cgroup_low(struct mem_cgroup *root, struct mem_cgroup *memcg) | |
5159 | { | |
5160 | if (mem_cgroup_disabled()) | |
5161 | return false; | |
5162 | ||
5163 | /* | |
5164 | * The toplevel group doesn't have a configurable range, so | |
5165 | * it's never low when looked at directly, and it is not | |
5166 | * considered an ancestor when assessing the hierarchy. | |
5167 | */ | |
5168 | ||
5169 | if (memcg == root_mem_cgroup) | |
5170 | return false; | |
5171 | ||
4e54dede | 5172 | if (page_counter_read(&memcg->memory) >= memcg->low) |
241994ed JW |
5173 | return false; |
5174 | ||
5175 | while (memcg != root) { | |
5176 | memcg = parent_mem_cgroup(memcg); | |
5177 | ||
5178 | if (memcg == root_mem_cgroup) | |
5179 | break; | |
5180 | ||
4e54dede | 5181 | if (page_counter_read(&memcg->memory) >= memcg->low) |
241994ed JW |
5182 | return false; |
5183 | } | |
5184 | return true; | |
5185 | } | |
5186 | ||
00501b53 JW |
5187 | /** |
5188 | * mem_cgroup_try_charge - try charging a page | |
5189 | * @page: page to charge | |
5190 | * @mm: mm context of the victim | |
5191 | * @gfp_mask: reclaim mode | |
5192 | * @memcgp: charged memcg return | |
5193 | * | |
5194 | * Try to charge @page to the memcg that @mm belongs to, reclaiming | |
5195 | * pages according to @gfp_mask if necessary. | |
5196 | * | |
5197 | * Returns 0 on success, with *@memcgp pointing to the charged memcg. | |
5198 | * Otherwise, an error code is returned. | |
5199 | * | |
5200 | * After page->mapping has been set up, the caller must finalize the | |
5201 | * charge with mem_cgroup_commit_charge(). Or abort the transaction | |
5202 | * with mem_cgroup_cancel_charge() in case page instantiation fails. | |
5203 | */ | |
5204 | int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm, | |
f627c2f5 KS |
5205 | gfp_t gfp_mask, struct mem_cgroup **memcgp, |
5206 | bool compound) | |
00501b53 JW |
5207 | { |
5208 | struct mem_cgroup *memcg = NULL; | |
f627c2f5 | 5209 | unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1; |
00501b53 JW |
5210 | int ret = 0; |
5211 | ||
5212 | if (mem_cgroup_disabled()) | |
5213 | goto out; | |
5214 | ||
5215 | if (PageSwapCache(page)) { | |
00501b53 JW |
5216 | /* |
5217 | * Every swap fault against a single page tries to charge the | |
5218 | * page, bail as early as possible. shmem_unuse() encounters | |
5219 | * already charged pages, too. The USED bit is protected by | |
5220 | * the page lock, which serializes swap cache removal, which | |
5221 | * in turn serializes uncharging. | |
5222 | */ | |
e993d905 | 5223 | VM_BUG_ON_PAGE(!PageLocked(page), page); |
1306a85a | 5224 | if (page->mem_cgroup) |
00501b53 | 5225 | goto out; |
e993d905 | 5226 | |
7941d214 | 5227 | if (do_memsw_account()) { |
e993d905 VD |
5228 | swp_entry_t ent = { .val = page_private(page), }; |
5229 | unsigned short id = lookup_swap_cgroup_id(ent); | |
5230 | ||
5231 | rcu_read_lock(); | |
5232 | memcg = mem_cgroup_from_id(id); | |
5233 | if (memcg && !css_tryget_online(&memcg->css)) | |
5234 | memcg = NULL; | |
5235 | rcu_read_unlock(); | |
5236 | } | |
00501b53 JW |
5237 | } |
5238 | ||
00501b53 JW |
5239 | if (!memcg) |
5240 | memcg = get_mem_cgroup_from_mm(mm); | |
5241 | ||
5242 | ret = try_charge(memcg, gfp_mask, nr_pages); | |
5243 | ||
5244 | css_put(&memcg->css); | |
00501b53 JW |
5245 | out: |
5246 | *memcgp = memcg; | |
5247 | return ret; | |
5248 | } | |
5249 | ||
5250 | /** | |
5251 | * mem_cgroup_commit_charge - commit a page charge | |
5252 | * @page: page to charge | |
5253 | * @memcg: memcg to charge the page to | |
5254 | * @lrucare: page might be on LRU already | |
5255 | * | |
5256 | * Finalize a charge transaction started by mem_cgroup_try_charge(), | |
5257 | * after page->mapping has been set up. This must happen atomically | |
5258 | * as part of the page instantiation, i.e. under the page table lock | |
5259 | * for anonymous pages, under the page lock for page and swap cache. | |
5260 | * | |
5261 | * In addition, the page must not be on the LRU during the commit, to | |
5262 | * prevent racing with task migration. If it might be, use @lrucare. | |
5263 | * | |
5264 | * Use mem_cgroup_cancel_charge() to cancel the transaction instead. | |
5265 | */ | |
5266 | void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg, | |
f627c2f5 | 5267 | bool lrucare, bool compound) |
00501b53 | 5268 | { |
f627c2f5 | 5269 | unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1; |
00501b53 JW |
5270 | |
5271 | VM_BUG_ON_PAGE(!page->mapping, page); | |
5272 | VM_BUG_ON_PAGE(PageLRU(page) && !lrucare, page); | |
5273 | ||
5274 | if (mem_cgroup_disabled()) | |
5275 | return; | |
5276 | /* | |
5277 | * Swap faults will attempt to charge the same page multiple | |
5278 | * times. But reuse_swap_page() might have removed the page | |
5279 | * from swapcache already, so we can't check PageSwapCache(). | |
5280 | */ | |
5281 | if (!memcg) | |
5282 | return; | |
5283 | ||
6abb5a86 JW |
5284 | commit_charge(page, memcg, lrucare); |
5285 | ||
6abb5a86 | 5286 | local_irq_disable(); |
f627c2f5 | 5287 | mem_cgroup_charge_statistics(memcg, page, compound, nr_pages); |
6abb5a86 JW |
5288 | memcg_check_events(memcg, page); |
5289 | local_irq_enable(); | |
00501b53 | 5290 | |
7941d214 | 5291 | if (do_memsw_account() && PageSwapCache(page)) { |
00501b53 JW |
5292 | swp_entry_t entry = { .val = page_private(page) }; |
5293 | /* | |
5294 | * The swap entry might not get freed for a long time, | |
5295 | * let's not wait for it. The page already received a | |
5296 | * memory+swap charge, drop the swap entry duplicate. | |
5297 | */ | |
5298 | mem_cgroup_uncharge_swap(entry); | |
5299 | } | |
5300 | } | |
5301 | ||
5302 | /** | |
5303 | * mem_cgroup_cancel_charge - cancel a page charge | |
5304 | * @page: page to charge | |
5305 | * @memcg: memcg to charge the page to | |
5306 | * | |
5307 | * Cancel a charge transaction started by mem_cgroup_try_charge(). | |
5308 | */ | |
f627c2f5 KS |
5309 | void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg, |
5310 | bool compound) | |
00501b53 | 5311 | { |
f627c2f5 | 5312 | unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1; |
00501b53 JW |
5313 | |
5314 | if (mem_cgroup_disabled()) | |
5315 | return; | |
5316 | /* | |
5317 | * Swap faults will attempt to charge the same page multiple | |
5318 | * times. But reuse_swap_page() might have removed the page | |
5319 | * from swapcache already, so we can't check PageSwapCache(). | |
5320 | */ | |
5321 | if (!memcg) | |
5322 | return; | |
5323 | ||
00501b53 JW |
5324 | cancel_charge(memcg, nr_pages); |
5325 | } | |
5326 | ||
747db954 | 5327 | static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout, |
747db954 JW |
5328 | unsigned long nr_anon, unsigned long nr_file, |
5329 | unsigned long nr_huge, struct page *dummy_page) | |
5330 | { | |
18eca2e6 | 5331 | unsigned long nr_pages = nr_anon + nr_file; |
747db954 JW |
5332 | unsigned long flags; |
5333 | ||
ce00a967 | 5334 | if (!mem_cgroup_is_root(memcg)) { |
18eca2e6 | 5335 | page_counter_uncharge(&memcg->memory, nr_pages); |
7941d214 | 5336 | if (do_memsw_account()) |
18eca2e6 | 5337 | page_counter_uncharge(&memcg->memsw, nr_pages); |
ce00a967 JW |
5338 | memcg_oom_recover(memcg); |
5339 | } | |
747db954 JW |
5340 | |
5341 | local_irq_save(flags); | |
5342 | __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS], nr_anon); | |
5343 | __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_file); | |
5344 | __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], nr_huge); | |
5345 | __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT], pgpgout); | |
18eca2e6 | 5346 | __this_cpu_add(memcg->stat->nr_page_events, nr_pages); |
747db954 JW |
5347 | memcg_check_events(memcg, dummy_page); |
5348 | local_irq_restore(flags); | |
e8ea14cc JW |
5349 | |
5350 | if (!mem_cgroup_is_root(memcg)) | |
18eca2e6 | 5351 | css_put_many(&memcg->css, nr_pages); |
747db954 JW |
5352 | } |
5353 | ||
5354 | static void uncharge_list(struct list_head *page_list) | |
5355 | { | |
5356 | struct mem_cgroup *memcg = NULL; | |
747db954 JW |
5357 | unsigned long nr_anon = 0; |
5358 | unsigned long nr_file = 0; | |
5359 | unsigned long nr_huge = 0; | |
5360 | unsigned long pgpgout = 0; | |
747db954 JW |
5361 | struct list_head *next; |
5362 | struct page *page; | |
5363 | ||
5364 | next = page_list->next; | |
5365 | do { | |
5366 | unsigned int nr_pages = 1; | |
747db954 JW |
5367 | |
5368 | page = list_entry(next, struct page, lru); | |
5369 | next = page->lru.next; | |
5370 | ||
5371 | VM_BUG_ON_PAGE(PageLRU(page), page); | |
5372 | VM_BUG_ON_PAGE(page_count(page), page); | |
5373 | ||
1306a85a | 5374 | if (!page->mem_cgroup) |
747db954 JW |
5375 | continue; |
5376 | ||
5377 | /* | |
5378 | * Nobody should be changing or seriously looking at | |
1306a85a | 5379 | * page->mem_cgroup at this point, we have fully |
29833315 | 5380 | * exclusive access to the page. |
747db954 JW |
5381 | */ |
5382 | ||
1306a85a | 5383 | if (memcg != page->mem_cgroup) { |
747db954 | 5384 | if (memcg) { |
18eca2e6 JW |
5385 | uncharge_batch(memcg, pgpgout, nr_anon, nr_file, |
5386 | nr_huge, page); | |
5387 | pgpgout = nr_anon = nr_file = nr_huge = 0; | |
747db954 | 5388 | } |
1306a85a | 5389 | memcg = page->mem_cgroup; |
747db954 JW |
5390 | } |
5391 | ||
5392 | if (PageTransHuge(page)) { | |
5393 | nr_pages <<= compound_order(page); | |
5394 | VM_BUG_ON_PAGE(!PageTransHuge(page), page); | |
5395 | nr_huge += nr_pages; | |
5396 | } | |
5397 | ||
5398 | if (PageAnon(page)) | |
5399 | nr_anon += nr_pages; | |
5400 | else | |
5401 | nr_file += nr_pages; | |
5402 | ||
1306a85a | 5403 | page->mem_cgroup = NULL; |
747db954 JW |
5404 | |
5405 | pgpgout++; | |
5406 | } while (next != page_list); | |
5407 | ||
5408 | if (memcg) | |
18eca2e6 JW |
5409 | uncharge_batch(memcg, pgpgout, nr_anon, nr_file, |
5410 | nr_huge, page); | |
747db954 JW |
5411 | } |
5412 | ||
0a31bc97 JW |
5413 | /** |
5414 | * mem_cgroup_uncharge - uncharge a page | |
5415 | * @page: page to uncharge | |
5416 | * | |
5417 | * Uncharge a page previously charged with mem_cgroup_try_charge() and | |
5418 | * mem_cgroup_commit_charge(). | |
5419 | */ | |
5420 | void mem_cgroup_uncharge(struct page *page) | |
5421 | { | |
0a31bc97 JW |
5422 | if (mem_cgroup_disabled()) |
5423 | return; | |
5424 | ||
747db954 | 5425 | /* Don't touch page->lru of any random page, pre-check: */ |
1306a85a | 5426 | if (!page->mem_cgroup) |
0a31bc97 JW |
5427 | return; |
5428 | ||
747db954 JW |
5429 | INIT_LIST_HEAD(&page->lru); |
5430 | uncharge_list(&page->lru); | |
5431 | } | |
0a31bc97 | 5432 | |
747db954 JW |
5433 | /** |
5434 | * mem_cgroup_uncharge_list - uncharge a list of page | |
5435 | * @page_list: list of pages to uncharge | |
5436 | * | |
5437 | * Uncharge a list of pages previously charged with | |
5438 | * mem_cgroup_try_charge() and mem_cgroup_commit_charge(). | |
5439 | */ | |
5440 | void mem_cgroup_uncharge_list(struct list_head *page_list) | |
5441 | { | |
5442 | if (mem_cgroup_disabled()) | |
5443 | return; | |
0a31bc97 | 5444 | |
747db954 JW |
5445 | if (!list_empty(page_list)) |
5446 | uncharge_list(page_list); | |
0a31bc97 JW |
5447 | } |
5448 | ||
5449 | /** | |
45637bab | 5450 | * mem_cgroup_replace_page - migrate a charge to another page |
0a31bc97 JW |
5451 | * @oldpage: currently charged page |
5452 | * @newpage: page to transfer the charge to | |
0a31bc97 JW |
5453 | * |
5454 | * Migrate the charge from @oldpage to @newpage. | |
5455 | * | |
5456 | * Both pages must be locked, @newpage->mapping must be set up. | |
25be6a65 | 5457 | * Either or both pages might be on the LRU already. |
0a31bc97 | 5458 | */ |
45637bab | 5459 | void mem_cgroup_replace_page(struct page *oldpage, struct page *newpage) |
0a31bc97 | 5460 | { |
29833315 | 5461 | struct mem_cgroup *memcg; |
0a31bc97 JW |
5462 | int isolated; |
5463 | ||
5464 | VM_BUG_ON_PAGE(!PageLocked(oldpage), oldpage); | |
5465 | VM_BUG_ON_PAGE(!PageLocked(newpage), newpage); | |
0a31bc97 | 5466 | VM_BUG_ON_PAGE(PageAnon(oldpage) != PageAnon(newpage), newpage); |
6abb5a86 JW |
5467 | VM_BUG_ON_PAGE(PageTransHuge(oldpage) != PageTransHuge(newpage), |
5468 | newpage); | |
0a31bc97 JW |
5469 | |
5470 | if (mem_cgroup_disabled()) | |
5471 | return; | |
5472 | ||
5473 | /* Page cache replacement: new page already charged? */ | |
1306a85a | 5474 | if (newpage->mem_cgroup) |
0a31bc97 JW |
5475 | return; |
5476 | ||
45637bab | 5477 | /* Swapcache readahead pages can get replaced before being charged */ |
1306a85a | 5478 | memcg = oldpage->mem_cgroup; |
29833315 | 5479 | if (!memcg) |
0a31bc97 JW |
5480 | return; |
5481 | ||
45637bab | 5482 | lock_page_lru(oldpage, &isolated); |
1306a85a | 5483 | oldpage->mem_cgroup = NULL; |
45637bab | 5484 | unlock_page_lru(oldpage, isolated); |
0a31bc97 | 5485 | |
45637bab | 5486 | commit_charge(newpage, memcg, true); |
0a31bc97 JW |
5487 | } |
5488 | ||
ef12947c | 5489 | DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key); |
11092087 JW |
5490 | EXPORT_SYMBOL(memcg_sockets_enabled_key); |
5491 | ||
5492 | void sock_update_memcg(struct sock *sk) | |
5493 | { | |
5494 | struct mem_cgroup *memcg; | |
5495 | ||
5496 | /* Socket cloning can throw us here with sk_cgrp already | |
5497 | * filled. It won't however, necessarily happen from | |
5498 | * process context. So the test for root memcg given | |
5499 | * the current task's memcg won't help us in this case. | |
5500 | * | |
5501 | * Respecting the original socket's memcg is a better | |
5502 | * decision in this case. | |
5503 | */ | |
5504 | if (sk->sk_memcg) { | |
5505 | BUG_ON(mem_cgroup_is_root(sk->sk_memcg)); | |
5506 | css_get(&sk->sk_memcg->css); | |
5507 | return; | |
5508 | } | |
5509 | ||
5510 | rcu_read_lock(); | |
5511 | memcg = mem_cgroup_from_task(current); | |
f7e1cb6e JW |
5512 | if (memcg == root_mem_cgroup) |
5513 | goto out; | |
0db15298 | 5514 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcpmem_active) |
f7e1cb6e | 5515 | goto out; |
f7e1cb6e | 5516 | if (css_tryget_online(&memcg->css)) |
11092087 | 5517 | sk->sk_memcg = memcg; |
f7e1cb6e | 5518 | out: |
11092087 JW |
5519 | rcu_read_unlock(); |
5520 | } | |
5521 | EXPORT_SYMBOL(sock_update_memcg); | |
5522 | ||
5523 | void sock_release_memcg(struct sock *sk) | |
5524 | { | |
5525 | WARN_ON(!sk->sk_memcg); | |
5526 | css_put(&sk->sk_memcg->css); | |
5527 | } | |
5528 | ||
5529 | /** | |
5530 | * mem_cgroup_charge_skmem - charge socket memory | |
5531 | * @memcg: memcg to charge | |
5532 | * @nr_pages: number of pages to charge | |
5533 | * | |
5534 | * Charges @nr_pages to @memcg. Returns %true if the charge fit within | |
5535 | * @memcg's configured limit, %false if the charge had to be forced. | |
5536 | */ | |
5537 | bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) | |
5538 | { | |
f7e1cb6e | 5539 | gfp_t gfp_mask = GFP_KERNEL; |
11092087 | 5540 | |
f7e1cb6e | 5541 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 5542 | struct page_counter *fail; |
f7e1cb6e | 5543 | |
0db15298 JW |
5544 | if (page_counter_try_charge(&memcg->tcpmem, nr_pages, &fail)) { |
5545 | memcg->tcpmem_pressure = 0; | |
f7e1cb6e JW |
5546 | return true; |
5547 | } | |
0db15298 JW |
5548 | page_counter_charge(&memcg->tcpmem, nr_pages); |
5549 | memcg->tcpmem_pressure = 1; | |
f7e1cb6e | 5550 | return false; |
11092087 | 5551 | } |
d886f4e4 | 5552 | |
f7e1cb6e JW |
5553 | /* Don't block in the packet receive path */ |
5554 | if (in_softirq()) | |
5555 | gfp_mask = GFP_NOWAIT; | |
5556 | ||
5557 | if (try_charge(memcg, gfp_mask, nr_pages) == 0) | |
5558 | return true; | |
5559 | ||
5560 | try_charge(memcg, gfp_mask|__GFP_NOFAIL, nr_pages); | |
11092087 JW |
5561 | return false; |
5562 | } | |
5563 | ||
5564 | /** | |
5565 | * mem_cgroup_uncharge_skmem - uncharge socket memory | |
5566 | * @memcg - memcg to uncharge | |
5567 | * @nr_pages - number of pages to uncharge | |
5568 | */ | |
5569 | void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) | |
5570 | { | |
f7e1cb6e | 5571 | if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { |
0db15298 | 5572 | page_counter_uncharge(&memcg->tcpmem, nr_pages); |
f7e1cb6e JW |
5573 | return; |
5574 | } | |
d886f4e4 | 5575 | |
f7e1cb6e JW |
5576 | page_counter_uncharge(&memcg->memory, nr_pages); |
5577 | css_put_many(&memcg->css, nr_pages); | |
11092087 JW |
5578 | } |
5579 | ||
f7e1cb6e JW |
5580 | static int __init cgroup_memory(char *s) |
5581 | { | |
5582 | char *token; | |
5583 | ||
5584 | while ((token = strsep(&s, ",")) != NULL) { | |
5585 | if (!*token) | |
5586 | continue; | |
5587 | if (!strcmp(token, "nosocket")) | |
5588 | cgroup_memory_nosocket = true; | |
04823c83 VD |
5589 | if (!strcmp(token, "nokmem")) |
5590 | cgroup_memory_nokmem = true; | |
f7e1cb6e JW |
5591 | } |
5592 | return 0; | |
5593 | } | |
5594 | __setup("cgroup.memory=", cgroup_memory); | |
11092087 | 5595 | |
2d11085e | 5596 | /* |
1081312f MH |
5597 | * subsys_initcall() for memory controller. |
5598 | * | |
5599 | * Some parts like hotcpu_notifier() have to be initialized from this context | |
5600 | * because of lock dependencies (cgroup_lock -> cpu hotplug) but basically | |
5601 | * everything that doesn't depend on a specific mem_cgroup structure should | |
5602 | * be initialized from here. | |
2d11085e MH |
5603 | */ |
5604 | static int __init mem_cgroup_init(void) | |
5605 | { | |
95a045f6 JW |
5606 | int cpu, node; |
5607 | ||
2d11085e | 5608 | hotcpu_notifier(memcg_cpu_hotplug_callback, 0); |
95a045f6 JW |
5609 | |
5610 | for_each_possible_cpu(cpu) | |
5611 | INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work, | |
5612 | drain_local_stock); | |
5613 | ||
5614 | for_each_node(node) { | |
5615 | struct mem_cgroup_tree_per_node *rtpn; | |
5616 | int zone; | |
5617 | ||
5618 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, | |
5619 | node_online(node) ? node : NUMA_NO_NODE); | |
5620 | ||
5621 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
5622 | struct mem_cgroup_tree_per_zone *rtpz; | |
5623 | ||
5624 | rtpz = &rtpn->rb_tree_per_zone[zone]; | |
5625 | rtpz->rb_root = RB_ROOT; | |
5626 | spin_lock_init(&rtpz->lock); | |
5627 | } | |
5628 | soft_limit_tree.rb_tree_per_node[node] = rtpn; | |
5629 | } | |
5630 | ||
2d11085e MH |
5631 | return 0; |
5632 | } | |
5633 | subsys_initcall(mem_cgroup_init); | |
21afa38e JW |
5634 | |
5635 | #ifdef CONFIG_MEMCG_SWAP | |
5636 | /** | |
5637 | * mem_cgroup_swapout - transfer a memsw charge to swap | |
5638 | * @page: page whose memsw charge to transfer | |
5639 | * @entry: swap entry to move the charge to | |
5640 | * | |
5641 | * Transfer the memsw charge of @page to @entry. | |
5642 | */ | |
5643 | void mem_cgroup_swapout(struct page *page, swp_entry_t entry) | |
5644 | { | |
5645 | struct mem_cgroup *memcg; | |
5646 | unsigned short oldid; | |
5647 | ||
5648 | VM_BUG_ON_PAGE(PageLRU(page), page); | |
5649 | VM_BUG_ON_PAGE(page_count(page), page); | |
5650 | ||
7941d214 | 5651 | if (!do_memsw_account()) |
21afa38e JW |
5652 | return; |
5653 | ||
5654 | memcg = page->mem_cgroup; | |
5655 | ||
5656 | /* Readahead page, never charged */ | |
5657 | if (!memcg) | |
5658 | return; | |
5659 | ||
5660 | oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg)); | |
5661 | VM_BUG_ON_PAGE(oldid, page); | |
5662 | mem_cgroup_swap_statistics(memcg, true); | |
5663 | ||
5664 | page->mem_cgroup = NULL; | |
5665 | ||
5666 | if (!mem_cgroup_is_root(memcg)) | |
5667 | page_counter_uncharge(&memcg->memory, 1); | |
5668 | ||
ce9ce665 SAS |
5669 | /* |
5670 | * Interrupts should be disabled here because the caller holds the | |
5671 | * mapping->tree_lock lock which is taken with interrupts-off. It is | |
5672 | * important here to have the interrupts disabled because it is the | |
5673 | * only synchronisation we have for udpating the per-CPU variables. | |
5674 | */ | |
5675 | VM_BUG_ON(!irqs_disabled()); | |
f627c2f5 | 5676 | mem_cgroup_charge_statistics(memcg, page, false, -1); |
21afa38e JW |
5677 | memcg_check_events(memcg, page); |
5678 | } | |
5679 | ||
5680 | /** | |
5681 | * mem_cgroup_uncharge_swap - uncharge a swap entry | |
5682 | * @entry: swap entry to uncharge | |
5683 | * | |
5684 | * Drop the memsw charge associated with @entry. | |
5685 | */ | |
5686 | void mem_cgroup_uncharge_swap(swp_entry_t entry) | |
5687 | { | |
5688 | struct mem_cgroup *memcg; | |
5689 | unsigned short id; | |
5690 | ||
7941d214 | 5691 | if (!do_memsw_account()) |
21afa38e JW |
5692 | return; |
5693 | ||
5694 | id = swap_cgroup_record(entry, 0); | |
5695 | rcu_read_lock(); | |
adbe427b | 5696 | memcg = mem_cgroup_from_id(id); |
21afa38e JW |
5697 | if (memcg) { |
5698 | if (!mem_cgroup_is_root(memcg)) | |
5699 | page_counter_uncharge(&memcg->memsw, 1); | |
5700 | mem_cgroup_swap_statistics(memcg, false); | |
5701 | css_put(&memcg->css); | |
5702 | } | |
5703 | rcu_read_unlock(); | |
5704 | } | |
5705 | ||
5706 | /* for remember boot option*/ | |
5707 | #ifdef CONFIG_MEMCG_SWAP_ENABLED | |
5708 | static int really_do_swap_account __initdata = 1; | |
5709 | #else | |
5710 | static int really_do_swap_account __initdata; | |
5711 | #endif | |
5712 | ||
5713 | static int __init enable_swap_account(char *s) | |
5714 | { | |
5715 | if (!strcmp(s, "1")) | |
5716 | really_do_swap_account = 1; | |
5717 | else if (!strcmp(s, "0")) | |
5718 | really_do_swap_account = 0; | |
5719 | return 1; | |
5720 | } | |
5721 | __setup("swapaccount=", enable_swap_account); | |
5722 | ||
5723 | static struct cftype memsw_cgroup_files[] = { | |
5724 | { | |
5725 | .name = "memsw.usage_in_bytes", | |
5726 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
5727 | .read_u64 = mem_cgroup_read_u64, | |
5728 | }, | |
5729 | { | |
5730 | .name = "memsw.max_usage_in_bytes", | |
5731 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
5732 | .write = mem_cgroup_reset, | |
5733 | .read_u64 = mem_cgroup_read_u64, | |
5734 | }, | |
5735 | { | |
5736 | .name = "memsw.limit_in_bytes", | |
5737 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
5738 | .write = mem_cgroup_write, | |
5739 | .read_u64 = mem_cgroup_read_u64, | |
5740 | }, | |
5741 | { | |
5742 | .name = "memsw.failcnt", | |
5743 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
5744 | .write = mem_cgroup_reset, | |
5745 | .read_u64 = mem_cgroup_read_u64, | |
5746 | }, | |
5747 | { }, /* terminate */ | |
5748 | }; | |
5749 | ||
5750 | static int __init mem_cgroup_swap_init(void) | |
5751 | { | |
5752 | if (!mem_cgroup_disabled() && really_do_swap_account) { | |
5753 | do_swap_account = 1; | |
5754 | WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, | |
5755 | memsw_cgroup_files)); | |
5756 | } | |
5757 | return 0; | |
5758 | } | |
5759 | subsys_initcall(mem_cgroup_swap_init); | |
5760 | ||
5761 | #endif /* CONFIG_MEMCG_SWAP */ |