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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 | * | |
8cdea7c0 BS |
17 | * This program is free software; you can redistribute it and/or modify |
18 | * it under the terms of the GNU General Public License as published by | |
19 | * the Free Software Foundation; either version 2 of the License, or | |
20 | * (at your option) any later version. | |
21 | * | |
22 | * This program is distributed in the hope that it will be useful, | |
23 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
24 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
25 | * GNU General Public License for more details. | |
26 | */ | |
27 | ||
28 | #include <linux/res_counter.h> | |
29 | #include <linux/memcontrol.h> | |
30 | #include <linux/cgroup.h> | |
78fb7466 | 31 | #include <linux/mm.h> |
4ffef5fe | 32 | #include <linux/hugetlb.h> |
d13d1443 | 33 | #include <linux/pagemap.h> |
d52aa412 | 34 | #include <linux/smp.h> |
8a9f3ccd | 35 | #include <linux/page-flags.h> |
66e1707b | 36 | #include <linux/backing-dev.h> |
8a9f3ccd BS |
37 | #include <linux/bit_spinlock.h> |
38 | #include <linux/rcupdate.h> | |
e222432b | 39 | #include <linux/limits.h> |
b9e15baf | 40 | #include <linux/export.h> |
8c7c6e34 | 41 | #include <linux/mutex.h> |
f64c3f54 | 42 | #include <linux/rbtree.h> |
b6ac57d5 | 43 | #include <linux/slab.h> |
66e1707b | 44 | #include <linux/swap.h> |
02491447 | 45 | #include <linux/swapops.h> |
66e1707b | 46 | #include <linux/spinlock.h> |
2e72b634 KS |
47 | #include <linux/eventfd.h> |
48 | #include <linux/sort.h> | |
66e1707b | 49 | #include <linux/fs.h> |
d2ceb9b7 | 50 | #include <linux/seq_file.h> |
33327948 | 51 | #include <linux/vmalloc.h> |
b69408e8 | 52 | #include <linux/mm_inline.h> |
52d4b9ac | 53 | #include <linux/page_cgroup.h> |
cdec2e42 | 54 | #include <linux/cpu.h> |
158e0a2d | 55 | #include <linux/oom.h> |
08e552c6 | 56 | #include "internal.h" |
d1a4c0b3 | 57 | #include <net/sock.h> |
4bd2c1ee | 58 | #include <net/ip.h> |
d1a4c0b3 | 59 | #include <net/tcp_memcontrol.h> |
8cdea7c0 | 60 | |
8697d331 BS |
61 | #include <asm/uaccess.h> |
62 | ||
cc8e970c KM |
63 | #include <trace/events/vmscan.h> |
64 | ||
a181b0e8 | 65 | struct cgroup_subsys mem_cgroup_subsys __read_mostly; |
68ae564b DR |
66 | EXPORT_SYMBOL(mem_cgroup_subsys); |
67 | ||
a181b0e8 | 68 | #define MEM_CGROUP_RECLAIM_RETRIES 5 |
6bbda35c | 69 | static struct mem_cgroup *root_mem_cgroup __read_mostly; |
8cdea7c0 | 70 | |
c255a458 | 71 | #ifdef CONFIG_MEMCG_SWAP |
338c8431 | 72 | /* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */ |
c077719b | 73 | int do_swap_account __read_mostly; |
a42c390c MH |
74 | |
75 | /* for remember boot option*/ | |
c255a458 | 76 | #ifdef CONFIG_MEMCG_SWAP_ENABLED |
a42c390c MH |
77 | static int really_do_swap_account __initdata = 1; |
78 | #else | |
79 | static int really_do_swap_account __initdata = 0; | |
80 | #endif | |
81 | ||
c077719b | 82 | #else |
a0db00fc | 83 | #define do_swap_account 0 |
c077719b KH |
84 | #endif |
85 | ||
86 | ||
d52aa412 KH |
87 | /* |
88 | * Statistics for memory cgroup. | |
89 | */ | |
90 | enum mem_cgroup_stat_index { | |
91 | /* | |
92 | * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss. | |
93 | */ | |
94 | MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */ | |
d69b042f | 95 | MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */ |
d8046582 | 96 | MEM_CGROUP_STAT_FILE_MAPPED, /* # of pages charged as file rss */ |
bff6bb83 | 97 | MEM_CGROUP_STAT_SWAP, /* # of pages, swapped out */ |
d52aa412 KH |
98 | MEM_CGROUP_STAT_NSTATS, |
99 | }; | |
100 | ||
af7c4b0e JW |
101 | static const char * const mem_cgroup_stat_names[] = { |
102 | "cache", | |
103 | "rss", | |
104 | "mapped_file", | |
105 | "swap", | |
106 | }; | |
107 | ||
e9f8974f JW |
108 | enum mem_cgroup_events_index { |
109 | MEM_CGROUP_EVENTS_PGPGIN, /* # of pages paged in */ | |
110 | MEM_CGROUP_EVENTS_PGPGOUT, /* # of pages paged out */ | |
456f998e YH |
111 | MEM_CGROUP_EVENTS_PGFAULT, /* # of page-faults */ |
112 | MEM_CGROUP_EVENTS_PGMAJFAULT, /* # of major page-faults */ | |
e9f8974f JW |
113 | MEM_CGROUP_EVENTS_NSTATS, |
114 | }; | |
af7c4b0e JW |
115 | |
116 | static const char * const mem_cgroup_events_names[] = { | |
117 | "pgpgin", | |
118 | "pgpgout", | |
119 | "pgfault", | |
120 | "pgmajfault", | |
121 | }; | |
122 | ||
7a159cc9 JW |
123 | /* |
124 | * Per memcg event counter is incremented at every pagein/pageout. With THP, | |
125 | * it will be incremated by the number of pages. This counter is used for | |
126 | * for trigger some periodic events. This is straightforward and better | |
127 | * than using jiffies etc. to handle periodic memcg event. | |
128 | */ | |
129 | enum mem_cgroup_events_target { | |
130 | MEM_CGROUP_TARGET_THRESH, | |
131 | MEM_CGROUP_TARGET_SOFTLIMIT, | |
453a9bf3 | 132 | MEM_CGROUP_TARGET_NUMAINFO, |
7a159cc9 JW |
133 | MEM_CGROUP_NTARGETS, |
134 | }; | |
a0db00fc KS |
135 | #define THRESHOLDS_EVENTS_TARGET 128 |
136 | #define SOFTLIMIT_EVENTS_TARGET 1024 | |
137 | #define NUMAINFO_EVENTS_TARGET 1024 | |
e9f8974f | 138 | |
d52aa412 | 139 | struct mem_cgroup_stat_cpu { |
7a159cc9 | 140 | long count[MEM_CGROUP_STAT_NSTATS]; |
e9f8974f | 141 | unsigned long events[MEM_CGROUP_EVENTS_NSTATS]; |
13114716 | 142 | unsigned long nr_page_events; |
7a159cc9 | 143 | unsigned long targets[MEM_CGROUP_NTARGETS]; |
d52aa412 KH |
144 | }; |
145 | ||
527a5ec9 JW |
146 | struct mem_cgroup_reclaim_iter { |
147 | /* css_id of the last scanned hierarchy member */ | |
148 | int position; | |
149 | /* scan generation, increased every round-trip */ | |
150 | unsigned int generation; | |
151 | }; | |
152 | ||
6d12e2d8 KH |
153 | /* |
154 | * per-zone information in memory controller. | |
155 | */ | |
6d12e2d8 | 156 | struct mem_cgroup_per_zone { |
6290df54 | 157 | struct lruvec lruvec; |
1eb49272 | 158 | unsigned long lru_size[NR_LRU_LISTS]; |
3e2f41f1 | 159 | |
527a5ec9 JW |
160 | struct mem_cgroup_reclaim_iter reclaim_iter[DEF_PRIORITY + 1]; |
161 | ||
f64c3f54 BS |
162 | struct rb_node tree_node; /* RB tree node */ |
163 | unsigned long long usage_in_excess;/* Set to the value by which */ | |
164 | /* the soft limit is exceeded*/ | |
165 | bool on_tree; | |
d79154bb | 166 | struct mem_cgroup *memcg; /* Back pointer, we cannot */ |
4e416953 | 167 | /* use container_of */ |
6d12e2d8 | 168 | }; |
6d12e2d8 KH |
169 | |
170 | struct mem_cgroup_per_node { | |
171 | struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES]; | |
172 | }; | |
173 | ||
174 | struct mem_cgroup_lru_info { | |
175 | struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES]; | |
176 | }; | |
177 | ||
f64c3f54 BS |
178 | /* |
179 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
180 | * their hierarchy representation | |
181 | */ | |
182 | ||
183 | struct mem_cgroup_tree_per_zone { | |
184 | struct rb_root rb_root; | |
185 | spinlock_t lock; | |
186 | }; | |
187 | ||
188 | struct mem_cgroup_tree_per_node { | |
189 | struct mem_cgroup_tree_per_zone rb_tree_per_zone[MAX_NR_ZONES]; | |
190 | }; | |
191 | ||
192 | struct mem_cgroup_tree { | |
193 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
194 | }; | |
195 | ||
196 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
197 | ||
2e72b634 KS |
198 | struct mem_cgroup_threshold { |
199 | struct eventfd_ctx *eventfd; | |
200 | u64 threshold; | |
201 | }; | |
202 | ||
9490ff27 | 203 | /* For threshold */ |
2e72b634 | 204 | struct mem_cgroup_threshold_ary { |
748dad36 | 205 | /* An array index points to threshold just below or equal to usage. */ |
5407a562 | 206 | int current_threshold; |
2e72b634 KS |
207 | /* Size of entries[] */ |
208 | unsigned int size; | |
209 | /* Array of thresholds */ | |
210 | struct mem_cgroup_threshold entries[0]; | |
211 | }; | |
2c488db2 KS |
212 | |
213 | struct mem_cgroup_thresholds { | |
214 | /* Primary thresholds array */ | |
215 | struct mem_cgroup_threshold_ary *primary; | |
216 | /* | |
217 | * Spare threshold array. | |
218 | * This is needed to make mem_cgroup_unregister_event() "never fail". | |
219 | * It must be able to store at least primary->size - 1 entries. | |
220 | */ | |
221 | struct mem_cgroup_threshold_ary *spare; | |
222 | }; | |
223 | ||
9490ff27 KH |
224 | /* for OOM */ |
225 | struct mem_cgroup_eventfd_list { | |
226 | struct list_head list; | |
227 | struct eventfd_ctx *eventfd; | |
228 | }; | |
2e72b634 | 229 | |
c0ff4b85 R |
230 | static void mem_cgroup_threshold(struct mem_cgroup *memcg); |
231 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); | |
2e72b634 | 232 | |
8cdea7c0 BS |
233 | /* |
234 | * The memory controller data structure. The memory controller controls both | |
235 | * page cache and RSS per cgroup. We would eventually like to provide | |
236 | * statistics based on the statistics developed by Rik Van Riel for clock-pro, | |
237 | * to help the administrator determine what knobs to tune. | |
238 | * | |
239 | * TODO: Add a water mark for the memory controller. Reclaim will begin when | |
8a9f3ccd BS |
240 | * we hit the water mark. May be even add a low water mark, such that |
241 | * no reclaim occurs from a cgroup at it's low water mark, this is | |
242 | * a feature that will be implemented much later in the future. | |
8cdea7c0 BS |
243 | */ |
244 | struct mem_cgroup { | |
245 | struct cgroup_subsys_state css; | |
246 | /* | |
247 | * the counter to account for memory usage | |
248 | */ | |
249 | struct res_counter res; | |
59927fb9 HD |
250 | |
251 | union { | |
252 | /* | |
253 | * the counter to account for mem+swap usage. | |
254 | */ | |
255 | struct res_counter memsw; | |
256 | ||
257 | /* | |
258 | * rcu_freeing is used only when freeing struct mem_cgroup, | |
259 | * so put it into a union to avoid wasting more memory. | |
260 | * It must be disjoint from the css field. It could be | |
261 | * in a union with the res field, but res plays a much | |
262 | * larger part in mem_cgroup life than memsw, and might | |
263 | * be of interest, even at time of free, when debugging. | |
264 | * So share rcu_head with the less interesting memsw. | |
265 | */ | |
266 | struct rcu_head rcu_freeing; | |
267 | /* | |
3afe36b1 GC |
268 | * We also need some space for a worker in deferred freeing. |
269 | * By the time we call it, rcu_freeing is no longer in use. | |
59927fb9 HD |
270 | */ |
271 | struct work_struct work_freeing; | |
272 | }; | |
273 | ||
510fc4e1 GC |
274 | /* |
275 | * the counter to account for kernel memory usage. | |
276 | */ | |
277 | struct res_counter kmem; | |
78fb7466 PE |
278 | /* |
279 | * Per cgroup active and inactive list, similar to the | |
280 | * per zone LRU lists. | |
78fb7466 | 281 | */ |
6d12e2d8 | 282 | struct mem_cgroup_lru_info info; |
889976db YH |
283 | int last_scanned_node; |
284 | #if MAX_NUMNODES > 1 | |
285 | nodemask_t scan_nodes; | |
453a9bf3 KH |
286 | atomic_t numainfo_events; |
287 | atomic_t numainfo_updating; | |
889976db | 288 | #endif |
18f59ea7 BS |
289 | /* |
290 | * Should the accounting and control be hierarchical, per subtree? | |
291 | */ | |
292 | bool use_hierarchy; | |
510fc4e1 | 293 | unsigned long kmem_account_flags; /* See KMEM_ACCOUNTED_*, below */ |
79dfdacc MH |
294 | |
295 | bool oom_lock; | |
296 | atomic_t under_oom; | |
297 | ||
8c7c6e34 | 298 | atomic_t refcnt; |
14797e23 | 299 | |
1f4c025b | 300 | int swappiness; |
3c11ecf4 KH |
301 | /* OOM-Killer disable */ |
302 | int oom_kill_disable; | |
a7885eb8 | 303 | |
22a668d7 KH |
304 | /* set when res.limit == memsw.limit */ |
305 | bool memsw_is_minimum; | |
306 | ||
2e72b634 KS |
307 | /* protect arrays of thresholds */ |
308 | struct mutex thresholds_lock; | |
309 | ||
310 | /* thresholds for memory usage. RCU-protected */ | |
2c488db2 | 311 | struct mem_cgroup_thresholds thresholds; |
907860ed | 312 | |
2e72b634 | 313 | /* thresholds for mem+swap usage. RCU-protected */ |
2c488db2 | 314 | struct mem_cgroup_thresholds memsw_thresholds; |
907860ed | 315 | |
9490ff27 KH |
316 | /* For oom notifier event fd */ |
317 | struct list_head oom_notify; | |
185efc0f | 318 | |
7dc74be0 DN |
319 | /* |
320 | * Should we move charges of a task when a task is moved into this | |
321 | * mem_cgroup ? And what type of charges should we move ? | |
322 | */ | |
323 | unsigned long move_charge_at_immigrate; | |
619d094b KH |
324 | /* |
325 | * set > 0 if pages under this cgroup are moving to other cgroup. | |
326 | */ | |
327 | atomic_t moving_account; | |
312734c0 KH |
328 | /* taken only while moving_account > 0 */ |
329 | spinlock_t move_lock; | |
d52aa412 | 330 | /* |
c62b1a3b | 331 | * percpu counter. |
d52aa412 | 332 | */ |
3a7951b4 | 333 | struct mem_cgroup_stat_cpu __percpu *stat; |
711d3d2c KH |
334 | /* |
335 | * used when a cpu is offlined or other synchronizations | |
336 | * See mem_cgroup_read_stat(). | |
337 | */ | |
338 | struct mem_cgroup_stat_cpu nocpu_base; | |
339 | spinlock_t pcp_counter_lock; | |
d1a4c0b3 | 340 | |
4bd2c1ee | 341 | #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_INET) |
d1a4c0b3 GC |
342 | struct tcp_memcontrol tcp_mem; |
343 | #endif | |
8cdea7c0 BS |
344 | }; |
345 | ||
510fc4e1 GC |
346 | /* internal only representation about the status of kmem accounting. */ |
347 | enum { | |
348 | KMEM_ACCOUNTED_ACTIVE = 0, /* accounted by this cgroup itself */ | |
a8964b9b | 349 | KMEM_ACCOUNTED_ACTIVATED, /* static key enabled. */ |
7de37682 | 350 | KMEM_ACCOUNTED_DEAD, /* dead memcg with pending kmem charges */ |
510fc4e1 GC |
351 | }; |
352 | ||
a8964b9b GC |
353 | /* We account when limit is on, but only after call sites are patched */ |
354 | #define KMEM_ACCOUNTED_MASK \ | |
355 | ((1 << KMEM_ACCOUNTED_ACTIVE) | (1 << KMEM_ACCOUNTED_ACTIVATED)) | |
510fc4e1 GC |
356 | |
357 | #ifdef CONFIG_MEMCG_KMEM | |
358 | static inline void memcg_kmem_set_active(struct mem_cgroup *memcg) | |
359 | { | |
360 | set_bit(KMEM_ACCOUNTED_ACTIVE, &memcg->kmem_account_flags); | |
361 | } | |
7de37682 GC |
362 | |
363 | static bool memcg_kmem_is_active(struct mem_cgroup *memcg) | |
364 | { | |
365 | return test_bit(KMEM_ACCOUNTED_ACTIVE, &memcg->kmem_account_flags); | |
366 | } | |
367 | ||
a8964b9b GC |
368 | static void memcg_kmem_set_activated(struct mem_cgroup *memcg) |
369 | { | |
370 | set_bit(KMEM_ACCOUNTED_ACTIVATED, &memcg->kmem_account_flags); | |
371 | } | |
372 | ||
7de37682 GC |
373 | static void memcg_kmem_mark_dead(struct mem_cgroup *memcg) |
374 | { | |
375 | if (test_bit(KMEM_ACCOUNTED_ACTIVE, &memcg->kmem_account_flags)) | |
376 | set_bit(KMEM_ACCOUNTED_DEAD, &memcg->kmem_account_flags); | |
377 | } | |
378 | ||
379 | static bool memcg_kmem_test_and_clear_dead(struct mem_cgroup *memcg) | |
380 | { | |
381 | return test_and_clear_bit(KMEM_ACCOUNTED_DEAD, | |
382 | &memcg->kmem_account_flags); | |
383 | } | |
510fc4e1 GC |
384 | #endif |
385 | ||
7dc74be0 DN |
386 | /* Stuffs for move charges at task migration. */ |
387 | /* | |
388 | * Types of charges to be moved. "move_charge_at_immitgrate" is treated as a | |
389 | * left-shifted bitmap of these types. | |
390 | */ | |
391 | enum move_type { | |
4ffef5fe | 392 | MOVE_CHARGE_TYPE_ANON, /* private anonymous page and swap of it */ |
87946a72 | 393 | MOVE_CHARGE_TYPE_FILE, /* file page(including tmpfs) and swap of it */ |
7dc74be0 DN |
394 | NR_MOVE_TYPE, |
395 | }; | |
396 | ||
4ffef5fe DN |
397 | /* "mc" and its members are protected by cgroup_mutex */ |
398 | static struct move_charge_struct { | |
b1dd693e | 399 | spinlock_t lock; /* for from, to */ |
4ffef5fe DN |
400 | struct mem_cgroup *from; |
401 | struct mem_cgroup *to; | |
402 | unsigned long precharge; | |
854ffa8d | 403 | unsigned long moved_charge; |
483c30b5 | 404 | unsigned long moved_swap; |
8033b97c DN |
405 | struct task_struct *moving_task; /* a task moving charges */ |
406 | wait_queue_head_t waitq; /* a waitq for other context */ | |
407 | } mc = { | |
2bd9bb20 | 408 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
409 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
410 | }; | |
4ffef5fe | 411 | |
90254a65 DN |
412 | static bool move_anon(void) |
413 | { | |
414 | return test_bit(MOVE_CHARGE_TYPE_ANON, | |
415 | &mc.to->move_charge_at_immigrate); | |
416 | } | |
417 | ||
87946a72 DN |
418 | static bool move_file(void) |
419 | { | |
420 | return test_bit(MOVE_CHARGE_TYPE_FILE, | |
421 | &mc.to->move_charge_at_immigrate); | |
422 | } | |
423 | ||
4e416953 BS |
424 | /* |
425 | * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft | |
426 | * limit reclaim to prevent infinite loops, if they ever occur. | |
427 | */ | |
a0db00fc KS |
428 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS 100 |
429 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS 2 | |
4e416953 | 430 | |
217bc319 KH |
431 | enum charge_type { |
432 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, | |
41326c17 | 433 | MEM_CGROUP_CHARGE_TYPE_ANON, |
d13d1443 | 434 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
8a9478ca | 435 | MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ |
c05555b5 KH |
436 | NR_CHARGE_TYPE, |
437 | }; | |
438 | ||
8c7c6e34 | 439 | /* for encoding cft->private value on file */ |
86ae53e1 GC |
440 | enum res_type { |
441 | _MEM, | |
442 | _MEMSWAP, | |
443 | _OOM_TYPE, | |
510fc4e1 | 444 | _KMEM, |
86ae53e1 GC |
445 | }; |
446 | ||
a0db00fc KS |
447 | #define MEMFILE_PRIVATE(x, val) ((x) << 16 | (val)) |
448 | #define MEMFILE_TYPE(val) ((val) >> 16 & 0xffff) | |
8c7c6e34 | 449 | #define MEMFILE_ATTR(val) ((val) & 0xffff) |
9490ff27 KH |
450 | /* Used for OOM nofiier */ |
451 | #define OOM_CONTROL (0) | |
8c7c6e34 | 452 | |
75822b44 BS |
453 | /* |
454 | * Reclaim flags for mem_cgroup_hierarchical_reclaim | |
455 | */ | |
456 | #define MEM_CGROUP_RECLAIM_NOSWAP_BIT 0x0 | |
457 | #define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT) | |
458 | #define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1 | |
459 | #define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT) | |
460 | ||
c0ff4b85 R |
461 | static void mem_cgroup_get(struct mem_cgroup *memcg); |
462 | static void mem_cgroup_put(struct mem_cgroup *memcg); | |
e1aab161 | 463 | |
b2145145 WL |
464 | static inline |
465 | struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *s) | |
466 | { | |
467 | return container_of(s, struct mem_cgroup, css); | |
468 | } | |
469 | ||
7ffc0edc MH |
470 | static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) |
471 | { | |
472 | return (memcg == root_mem_cgroup); | |
473 | } | |
474 | ||
e1aab161 | 475 | /* Writing them here to avoid exposing memcg's inner layout */ |
4bd2c1ee | 476 | #if defined(CONFIG_INET) && defined(CONFIG_MEMCG_KMEM) |
e1aab161 | 477 | |
e1aab161 GC |
478 | void sock_update_memcg(struct sock *sk) |
479 | { | |
376be5ff | 480 | if (mem_cgroup_sockets_enabled) { |
e1aab161 | 481 | struct mem_cgroup *memcg; |
3f134619 | 482 | struct cg_proto *cg_proto; |
e1aab161 GC |
483 | |
484 | BUG_ON(!sk->sk_prot->proto_cgroup); | |
485 | ||
f3f511e1 GC |
486 | /* Socket cloning can throw us here with sk_cgrp already |
487 | * filled. It won't however, necessarily happen from | |
488 | * process context. So the test for root memcg given | |
489 | * the current task's memcg won't help us in this case. | |
490 | * | |
491 | * Respecting the original socket's memcg is a better | |
492 | * decision in this case. | |
493 | */ | |
494 | if (sk->sk_cgrp) { | |
495 | BUG_ON(mem_cgroup_is_root(sk->sk_cgrp->memcg)); | |
496 | mem_cgroup_get(sk->sk_cgrp->memcg); | |
497 | return; | |
498 | } | |
499 | ||
e1aab161 GC |
500 | rcu_read_lock(); |
501 | memcg = mem_cgroup_from_task(current); | |
3f134619 GC |
502 | cg_proto = sk->sk_prot->proto_cgroup(memcg); |
503 | if (!mem_cgroup_is_root(memcg) && memcg_proto_active(cg_proto)) { | |
e1aab161 | 504 | mem_cgroup_get(memcg); |
3f134619 | 505 | sk->sk_cgrp = cg_proto; |
e1aab161 GC |
506 | } |
507 | rcu_read_unlock(); | |
508 | } | |
509 | } | |
510 | EXPORT_SYMBOL(sock_update_memcg); | |
511 | ||
512 | void sock_release_memcg(struct sock *sk) | |
513 | { | |
376be5ff | 514 | if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { |
e1aab161 GC |
515 | struct mem_cgroup *memcg; |
516 | WARN_ON(!sk->sk_cgrp->memcg); | |
517 | memcg = sk->sk_cgrp->memcg; | |
518 | mem_cgroup_put(memcg); | |
519 | } | |
520 | } | |
d1a4c0b3 GC |
521 | |
522 | struct cg_proto *tcp_proto_cgroup(struct mem_cgroup *memcg) | |
523 | { | |
524 | if (!memcg || mem_cgroup_is_root(memcg)) | |
525 | return NULL; | |
526 | ||
527 | return &memcg->tcp_mem.cg_proto; | |
528 | } | |
529 | EXPORT_SYMBOL(tcp_proto_cgroup); | |
e1aab161 | 530 | |
3f134619 GC |
531 | static void disarm_sock_keys(struct mem_cgroup *memcg) |
532 | { | |
533 | if (!memcg_proto_activated(&memcg->tcp_mem.cg_proto)) | |
534 | return; | |
535 | static_key_slow_dec(&memcg_socket_limit_enabled); | |
536 | } | |
537 | #else | |
538 | static void disarm_sock_keys(struct mem_cgroup *memcg) | |
539 | { | |
540 | } | |
541 | #endif | |
542 | ||
a8964b9b GC |
543 | #ifdef CONFIG_MEMCG_KMEM |
544 | struct static_key memcg_kmem_enabled_key; | |
545 | ||
546 | static void disarm_kmem_keys(struct mem_cgroup *memcg) | |
547 | { | |
548 | if (memcg_kmem_is_active(memcg)) | |
549 | static_key_slow_dec(&memcg_kmem_enabled_key); | |
550 | } | |
551 | #else | |
552 | static void disarm_kmem_keys(struct mem_cgroup *memcg) | |
553 | { | |
554 | } | |
555 | #endif /* CONFIG_MEMCG_KMEM */ | |
556 | ||
557 | static void disarm_static_keys(struct mem_cgroup *memcg) | |
558 | { | |
559 | disarm_sock_keys(memcg); | |
560 | disarm_kmem_keys(memcg); | |
561 | } | |
562 | ||
c0ff4b85 | 563 | static void drain_all_stock_async(struct mem_cgroup *memcg); |
8c7c6e34 | 564 | |
f64c3f54 | 565 | static struct mem_cgroup_per_zone * |
c0ff4b85 | 566 | mem_cgroup_zoneinfo(struct mem_cgroup *memcg, int nid, int zid) |
f64c3f54 | 567 | { |
c0ff4b85 | 568 | return &memcg->info.nodeinfo[nid]->zoneinfo[zid]; |
f64c3f54 BS |
569 | } |
570 | ||
c0ff4b85 | 571 | struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *memcg) |
d324236b | 572 | { |
c0ff4b85 | 573 | return &memcg->css; |
d324236b WF |
574 | } |
575 | ||
f64c3f54 | 576 | static struct mem_cgroup_per_zone * |
c0ff4b85 | 577 | page_cgroup_zoneinfo(struct mem_cgroup *memcg, struct page *page) |
f64c3f54 | 578 | { |
97a6c37b JW |
579 | int nid = page_to_nid(page); |
580 | int zid = page_zonenum(page); | |
f64c3f54 | 581 | |
c0ff4b85 | 582 | return mem_cgroup_zoneinfo(memcg, nid, zid); |
f64c3f54 BS |
583 | } |
584 | ||
585 | static struct mem_cgroup_tree_per_zone * | |
586 | soft_limit_tree_node_zone(int nid, int zid) | |
587 | { | |
588 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
589 | } | |
590 | ||
591 | static struct mem_cgroup_tree_per_zone * | |
592 | soft_limit_tree_from_page(struct page *page) | |
593 | { | |
594 | int nid = page_to_nid(page); | |
595 | int zid = page_zonenum(page); | |
596 | ||
597 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
598 | } | |
599 | ||
600 | static void | |
c0ff4b85 | 601 | __mem_cgroup_insert_exceeded(struct mem_cgroup *memcg, |
f64c3f54 | 602 | struct mem_cgroup_per_zone *mz, |
ef8745c1 KH |
603 | struct mem_cgroup_tree_per_zone *mctz, |
604 | unsigned long long new_usage_in_excess) | |
f64c3f54 BS |
605 | { |
606 | struct rb_node **p = &mctz->rb_root.rb_node; | |
607 | struct rb_node *parent = NULL; | |
608 | struct mem_cgroup_per_zone *mz_node; | |
609 | ||
610 | if (mz->on_tree) | |
611 | return; | |
612 | ||
ef8745c1 KH |
613 | mz->usage_in_excess = new_usage_in_excess; |
614 | if (!mz->usage_in_excess) | |
615 | return; | |
f64c3f54 BS |
616 | while (*p) { |
617 | parent = *p; | |
618 | mz_node = rb_entry(parent, struct mem_cgroup_per_zone, | |
619 | tree_node); | |
620 | if (mz->usage_in_excess < mz_node->usage_in_excess) | |
621 | p = &(*p)->rb_left; | |
622 | /* | |
623 | * We can't avoid mem cgroups that are over their soft | |
624 | * limit by the same amount | |
625 | */ | |
626 | else if (mz->usage_in_excess >= mz_node->usage_in_excess) | |
627 | p = &(*p)->rb_right; | |
628 | } | |
629 | rb_link_node(&mz->tree_node, parent, p); | |
630 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
631 | mz->on_tree = true; | |
4e416953 BS |
632 | } |
633 | ||
634 | static void | |
c0ff4b85 | 635 | __mem_cgroup_remove_exceeded(struct mem_cgroup *memcg, |
4e416953 BS |
636 | struct mem_cgroup_per_zone *mz, |
637 | struct mem_cgroup_tree_per_zone *mctz) | |
638 | { | |
639 | if (!mz->on_tree) | |
640 | return; | |
641 | rb_erase(&mz->tree_node, &mctz->rb_root); | |
642 | mz->on_tree = false; | |
643 | } | |
644 | ||
f64c3f54 | 645 | static void |
c0ff4b85 | 646 | mem_cgroup_remove_exceeded(struct mem_cgroup *memcg, |
f64c3f54 BS |
647 | struct mem_cgroup_per_zone *mz, |
648 | struct mem_cgroup_tree_per_zone *mctz) | |
649 | { | |
650 | spin_lock(&mctz->lock); | |
c0ff4b85 | 651 | __mem_cgroup_remove_exceeded(memcg, mz, mctz); |
f64c3f54 BS |
652 | spin_unlock(&mctz->lock); |
653 | } | |
654 | ||
f64c3f54 | 655 | |
c0ff4b85 | 656 | static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page) |
f64c3f54 | 657 | { |
ef8745c1 | 658 | unsigned long long excess; |
f64c3f54 BS |
659 | struct mem_cgroup_per_zone *mz; |
660 | struct mem_cgroup_tree_per_zone *mctz; | |
4e649152 KH |
661 | int nid = page_to_nid(page); |
662 | int zid = page_zonenum(page); | |
f64c3f54 BS |
663 | mctz = soft_limit_tree_from_page(page); |
664 | ||
665 | /* | |
4e649152 KH |
666 | * Necessary to update all ancestors when hierarchy is used. |
667 | * because their event counter is not touched. | |
f64c3f54 | 668 | */ |
c0ff4b85 R |
669 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { |
670 | mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
671 | excess = res_counter_soft_limit_excess(&memcg->res); | |
4e649152 KH |
672 | /* |
673 | * We have to update the tree if mz is on RB-tree or | |
674 | * mem is over its softlimit. | |
675 | */ | |
ef8745c1 | 676 | if (excess || mz->on_tree) { |
4e649152 KH |
677 | spin_lock(&mctz->lock); |
678 | /* if on-tree, remove it */ | |
679 | if (mz->on_tree) | |
c0ff4b85 | 680 | __mem_cgroup_remove_exceeded(memcg, mz, mctz); |
4e649152 | 681 | /* |
ef8745c1 KH |
682 | * Insert again. mz->usage_in_excess will be updated. |
683 | * If excess is 0, no tree ops. | |
4e649152 | 684 | */ |
c0ff4b85 | 685 | __mem_cgroup_insert_exceeded(memcg, mz, mctz, excess); |
4e649152 KH |
686 | spin_unlock(&mctz->lock); |
687 | } | |
f64c3f54 BS |
688 | } |
689 | } | |
690 | ||
c0ff4b85 | 691 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) |
f64c3f54 BS |
692 | { |
693 | int node, zone; | |
694 | struct mem_cgroup_per_zone *mz; | |
695 | struct mem_cgroup_tree_per_zone *mctz; | |
696 | ||
3ed28fa1 | 697 | for_each_node(node) { |
f64c3f54 | 698 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
c0ff4b85 | 699 | mz = mem_cgroup_zoneinfo(memcg, node, zone); |
f64c3f54 | 700 | mctz = soft_limit_tree_node_zone(node, zone); |
c0ff4b85 | 701 | mem_cgroup_remove_exceeded(memcg, mz, mctz); |
f64c3f54 BS |
702 | } |
703 | } | |
704 | } | |
705 | ||
4e416953 BS |
706 | static struct mem_cgroup_per_zone * |
707 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
708 | { | |
709 | struct rb_node *rightmost = NULL; | |
26251eaf | 710 | struct mem_cgroup_per_zone *mz; |
4e416953 BS |
711 | |
712 | retry: | |
26251eaf | 713 | mz = NULL; |
4e416953 BS |
714 | rightmost = rb_last(&mctz->rb_root); |
715 | if (!rightmost) | |
716 | goto done; /* Nothing to reclaim from */ | |
717 | ||
718 | mz = rb_entry(rightmost, struct mem_cgroup_per_zone, tree_node); | |
719 | /* | |
720 | * Remove the node now but someone else can add it back, | |
721 | * we will to add it back at the end of reclaim to its correct | |
722 | * position in the tree. | |
723 | */ | |
d79154bb HD |
724 | __mem_cgroup_remove_exceeded(mz->memcg, mz, mctz); |
725 | if (!res_counter_soft_limit_excess(&mz->memcg->res) || | |
726 | !css_tryget(&mz->memcg->css)) | |
4e416953 BS |
727 | goto retry; |
728 | done: | |
729 | return mz; | |
730 | } | |
731 | ||
732 | static struct mem_cgroup_per_zone * | |
733 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
734 | { | |
735 | struct mem_cgroup_per_zone *mz; | |
736 | ||
737 | spin_lock(&mctz->lock); | |
738 | mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
739 | spin_unlock(&mctz->lock); | |
740 | return mz; | |
741 | } | |
742 | ||
711d3d2c KH |
743 | /* |
744 | * Implementation Note: reading percpu statistics for memcg. | |
745 | * | |
746 | * Both of vmstat[] and percpu_counter has threshold and do periodic | |
747 | * synchronization to implement "quick" read. There are trade-off between | |
748 | * reading cost and precision of value. Then, we may have a chance to implement | |
749 | * a periodic synchronizion of counter in memcg's counter. | |
750 | * | |
751 | * But this _read() function is used for user interface now. The user accounts | |
752 | * memory usage by memory cgroup and he _always_ requires exact value because | |
753 | * he accounts memory. Even if we provide quick-and-fuzzy read, we always | |
754 | * have to visit all online cpus and make sum. So, for now, unnecessary | |
755 | * synchronization is not implemented. (just implemented for cpu hotplug) | |
756 | * | |
757 | * If there are kernel internal actions which can make use of some not-exact | |
758 | * value, and reading all cpu value can be performance bottleneck in some | |
759 | * common workload, threashold and synchonization as vmstat[] should be | |
760 | * implemented. | |
761 | */ | |
c0ff4b85 | 762 | static long mem_cgroup_read_stat(struct mem_cgroup *memcg, |
7a159cc9 | 763 | enum mem_cgroup_stat_index idx) |
c62b1a3b | 764 | { |
7a159cc9 | 765 | long val = 0; |
c62b1a3b | 766 | int cpu; |
c62b1a3b | 767 | |
711d3d2c KH |
768 | get_online_cpus(); |
769 | for_each_online_cpu(cpu) | |
c0ff4b85 | 770 | val += per_cpu(memcg->stat->count[idx], cpu); |
711d3d2c | 771 | #ifdef CONFIG_HOTPLUG_CPU |
c0ff4b85 R |
772 | spin_lock(&memcg->pcp_counter_lock); |
773 | val += memcg->nocpu_base.count[idx]; | |
774 | spin_unlock(&memcg->pcp_counter_lock); | |
711d3d2c KH |
775 | #endif |
776 | put_online_cpus(); | |
c62b1a3b KH |
777 | return val; |
778 | } | |
779 | ||
c0ff4b85 | 780 | static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg, |
0c3e73e8 BS |
781 | bool charge) |
782 | { | |
783 | int val = (charge) ? 1 : -1; | |
bff6bb83 | 784 | this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_SWAP], val); |
0c3e73e8 BS |
785 | } |
786 | ||
c0ff4b85 | 787 | static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg, |
e9f8974f JW |
788 | enum mem_cgroup_events_index idx) |
789 | { | |
790 | unsigned long val = 0; | |
791 | int cpu; | |
792 | ||
793 | for_each_online_cpu(cpu) | |
c0ff4b85 | 794 | val += per_cpu(memcg->stat->events[idx], cpu); |
e9f8974f | 795 | #ifdef CONFIG_HOTPLUG_CPU |
c0ff4b85 R |
796 | spin_lock(&memcg->pcp_counter_lock); |
797 | val += memcg->nocpu_base.events[idx]; | |
798 | spin_unlock(&memcg->pcp_counter_lock); | |
e9f8974f JW |
799 | #endif |
800 | return val; | |
801 | } | |
802 | ||
c0ff4b85 | 803 | static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, |
b2402857 | 804 | bool anon, int nr_pages) |
d52aa412 | 805 | { |
c62b1a3b KH |
806 | preempt_disable(); |
807 | ||
b2402857 KH |
808 | /* |
809 | * Here, RSS means 'mapped anon' and anon's SwapCache. Shmem/tmpfs is | |
810 | * counted as CACHE even if it's on ANON LRU. | |
811 | */ | |
812 | if (anon) | |
813 | __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_RSS], | |
c0ff4b85 | 814 | nr_pages); |
d52aa412 | 815 | else |
b2402857 | 816 | __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_CACHE], |
c0ff4b85 | 817 | nr_pages); |
55e462b0 | 818 | |
e401f176 KH |
819 | /* pagein of a big page is an event. So, ignore page size */ |
820 | if (nr_pages > 0) | |
c0ff4b85 | 821 | __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGIN]); |
3751d604 | 822 | else { |
c0ff4b85 | 823 | __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT]); |
3751d604 KH |
824 | nr_pages = -nr_pages; /* for event */ |
825 | } | |
e401f176 | 826 | |
13114716 | 827 | __this_cpu_add(memcg->stat->nr_page_events, nr_pages); |
2e72b634 | 828 | |
c62b1a3b | 829 | preempt_enable(); |
6d12e2d8 KH |
830 | } |
831 | ||
bb2a0de9 | 832 | unsigned long |
4d7dcca2 | 833 | mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru) |
074291fe KK |
834 | { |
835 | struct mem_cgroup_per_zone *mz; | |
836 | ||
837 | mz = container_of(lruvec, struct mem_cgroup_per_zone, lruvec); | |
838 | return mz->lru_size[lru]; | |
839 | } | |
840 | ||
841 | static unsigned long | |
c0ff4b85 | 842 | mem_cgroup_zone_nr_lru_pages(struct mem_cgroup *memcg, int nid, int zid, |
bb2a0de9 | 843 | unsigned int lru_mask) |
889976db YH |
844 | { |
845 | struct mem_cgroup_per_zone *mz; | |
f156ab93 | 846 | enum lru_list lru; |
bb2a0de9 KH |
847 | unsigned long ret = 0; |
848 | ||
c0ff4b85 | 849 | mz = mem_cgroup_zoneinfo(memcg, nid, zid); |
bb2a0de9 | 850 | |
f156ab93 HD |
851 | for_each_lru(lru) { |
852 | if (BIT(lru) & lru_mask) | |
853 | ret += mz->lru_size[lru]; | |
bb2a0de9 KH |
854 | } |
855 | return ret; | |
856 | } | |
857 | ||
858 | static unsigned long | |
c0ff4b85 | 859 | mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, |
bb2a0de9 KH |
860 | int nid, unsigned int lru_mask) |
861 | { | |
889976db YH |
862 | u64 total = 0; |
863 | int zid; | |
864 | ||
bb2a0de9 | 865 | for (zid = 0; zid < MAX_NR_ZONES; zid++) |
c0ff4b85 R |
866 | total += mem_cgroup_zone_nr_lru_pages(memcg, |
867 | nid, zid, lru_mask); | |
bb2a0de9 | 868 | |
889976db YH |
869 | return total; |
870 | } | |
bb2a0de9 | 871 | |
c0ff4b85 | 872 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, |
bb2a0de9 | 873 | unsigned int lru_mask) |
6d12e2d8 | 874 | { |
889976db | 875 | int nid; |
6d12e2d8 KH |
876 | u64 total = 0; |
877 | ||
31aaea4a | 878 | for_each_node_state(nid, N_MEMORY) |
c0ff4b85 | 879 | total += mem_cgroup_node_nr_lru_pages(memcg, nid, lru_mask); |
6d12e2d8 | 880 | return total; |
d52aa412 KH |
881 | } |
882 | ||
f53d7ce3 JW |
883 | static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg, |
884 | enum mem_cgroup_events_target target) | |
7a159cc9 JW |
885 | { |
886 | unsigned long val, next; | |
887 | ||
13114716 | 888 | val = __this_cpu_read(memcg->stat->nr_page_events); |
4799401f | 889 | next = __this_cpu_read(memcg->stat->targets[target]); |
7a159cc9 | 890 | /* from time_after() in jiffies.h */ |
f53d7ce3 JW |
891 | if ((long)next - (long)val < 0) { |
892 | switch (target) { | |
893 | case MEM_CGROUP_TARGET_THRESH: | |
894 | next = val + THRESHOLDS_EVENTS_TARGET; | |
895 | break; | |
896 | case MEM_CGROUP_TARGET_SOFTLIMIT: | |
897 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
898 | break; | |
899 | case MEM_CGROUP_TARGET_NUMAINFO: | |
900 | next = val + NUMAINFO_EVENTS_TARGET; | |
901 | break; | |
902 | default: | |
903 | break; | |
904 | } | |
905 | __this_cpu_write(memcg->stat->targets[target], next); | |
906 | return true; | |
7a159cc9 | 907 | } |
f53d7ce3 | 908 | return false; |
d2265e6f KH |
909 | } |
910 | ||
911 | /* | |
912 | * Check events in order. | |
913 | * | |
914 | */ | |
c0ff4b85 | 915 | static void memcg_check_events(struct mem_cgroup *memcg, struct page *page) |
d2265e6f | 916 | { |
4799401f | 917 | preempt_disable(); |
d2265e6f | 918 | /* threshold event is triggered in finer grain than soft limit */ |
f53d7ce3 JW |
919 | if (unlikely(mem_cgroup_event_ratelimit(memcg, |
920 | MEM_CGROUP_TARGET_THRESH))) { | |
82b3f2a7 AM |
921 | bool do_softlimit; |
922 | bool do_numainfo __maybe_unused; | |
f53d7ce3 JW |
923 | |
924 | do_softlimit = mem_cgroup_event_ratelimit(memcg, | |
925 | MEM_CGROUP_TARGET_SOFTLIMIT); | |
926 | #if MAX_NUMNODES > 1 | |
927 | do_numainfo = mem_cgroup_event_ratelimit(memcg, | |
928 | MEM_CGROUP_TARGET_NUMAINFO); | |
929 | #endif | |
930 | preempt_enable(); | |
931 | ||
c0ff4b85 | 932 | mem_cgroup_threshold(memcg); |
f53d7ce3 | 933 | if (unlikely(do_softlimit)) |
c0ff4b85 | 934 | mem_cgroup_update_tree(memcg, page); |
453a9bf3 | 935 | #if MAX_NUMNODES > 1 |
f53d7ce3 | 936 | if (unlikely(do_numainfo)) |
c0ff4b85 | 937 | atomic_inc(&memcg->numainfo_events); |
453a9bf3 | 938 | #endif |
f53d7ce3 JW |
939 | } else |
940 | preempt_enable(); | |
d2265e6f KH |
941 | } |
942 | ||
d1a4c0b3 | 943 | struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) |
8cdea7c0 | 944 | { |
b2145145 WL |
945 | return mem_cgroup_from_css( |
946 | cgroup_subsys_state(cont, mem_cgroup_subsys_id)); | |
8cdea7c0 BS |
947 | } |
948 | ||
cf475ad2 | 949 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 950 | { |
31a78f23 BS |
951 | /* |
952 | * mm_update_next_owner() may clear mm->owner to NULL | |
953 | * if it races with swapoff, page migration, etc. | |
954 | * So this can be called with p == NULL. | |
955 | */ | |
956 | if (unlikely(!p)) | |
957 | return NULL; | |
958 | ||
b2145145 | 959 | return mem_cgroup_from_css(task_subsys_state(p, mem_cgroup_subsys_id)); |
78fb7466 PE |
960 | } |
961 | ||
a433658c | 962 | struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) |
54595fe2 | 963 | { |
c0ff4b85 | 964 | struct mem_cgroup *memcg = NULL; |
0b7f569e KH |
965 | |
966 | if (!mm) | |
967 | return NULL; | |
54595fe2 KH |
968 | /* |
969 | * Because we have no locks, mm->owner's may be being moved to other | |
970 | * cgroup. We use css_tryget() here even if this looks | |
971 | * pessimistic (rather than adding locks here). | |
972 | */ | |
973 | rcu_read_lock(); | |
974 | do { | |
c0ff4b85 R |
975 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); |
976 | if (unlikely(!memcg)) | |
54595fe2 | 977 | break; |
c0ff4b85 | 978 | } while (!css_tryget(&memcg->css)); |
54595fe2 | 979 | rcu_read_unlock(); |
c0ff4b85 | 980 | return memcg; |
54595fe2 KH |
981 | } |
982 | ||
5660048c JW |
983 | /** |
984 | * mem_cgroup_iter - iterate over memory cgroup hierarchy | |
985 | * @root: hierarchy root | |
986 | * @prev: previously returned memcg, NULL on first invocation | |
987 | * @reclaim: cookie for shared reclaim walks, NULL for full walks | |
988 | * | |
989 | * Returns references to children of the hierarchy below @root, or | |
990 | * @root itself, or %NULL after a full round-trip. | |
991 | * | |
992 | * Caller must pass the return value in @prev on subsequent | |
993 | * invocations for reference counting, or use mem_cgroup_iter_break() | |
994 | * to cancel a hierarchy walk before the round-trip is complete. | |
995 | * | |
996 | * Reclaimers can specify a zone and a priority level in @reclaim to | |
997 | * divide up the memcgs in the hierarchy among all concurrent | |
998 | * reclaimers operating on the same zone and priority. | |
999 | */ | |
1000 | struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, | |
1001 | struct mem_cgroup *prev, | |
1002 | struct mem_cgroup_reclaim_cookie *reclaim) | |
14067bb3 | 1003 | { |
9f3a0d09 JW |
1004 | struct mem_cgroup *memcg = NULL; |
1005 | int id = 0; | |
711d3d2c | 1006 | |
5660048c JW |
1007 | if (mem_cgroup_disabled()) |
1008 | return NULL; | |
1009 | ||
9f3a0d09 JW |
1010 | if (!root) |
1011 | root = root_mem_cgroup; | |
7d74b06f | 1012 | |
9f3a0d09 JW |
1013 | if (prev && !reclaim) |
1014 | id = css_id(&prev->css); | |
14067bb3 | 1015 | |
9f3a0d09 JW |
1016 | if (prev && prev != root) |
1017 | css_put(&prev->css); | |
14067bb3 | 1018 | |
9f3a0d09 JW |
1019 | if (!root->use_hierarchy && root != root_mem_cgroup) { |
1020 | if (prev) | |
1021 | return NULL; | |
1022 | return root; | |
1023 | } | |
14067bb3 | 1024 | |
9f3a0d09 | 1025 | while (!memcg) { |
527a5ec9 | 1026 | struct mem_cgroup_reclaim_iter *uninitialized_var(iter); |
9f3a0d09 | 1027 | struct cgroup_subsys_state *css; |
711d3d2c | 1028 | |
527a5ec9 JW |
1029 | if (reclaim) { |
1030 | int nid = zone_to_nid(reclaim->zone); | |
1031 | int zid = zone_idx(reclaim->zone); | |
1032 | struct mem_cgroup_per_zone *mz; | |
1033 | ||
1034 | mz = mem_cgroup_zoneinfo(root, nid, zid); | |
1035 | iter = &mz->reclaim_iter[reclaim->priority]; | |
1036 | if (prev && reclaim->generation != iter->generation) | |
1037 | return NULL; | |
1038 | id = iter->position; | |
1039 | } | |
7d74b06f | 1040 | |
9f3a0d09 JW |
1041 | rcu_read_lock(); |
1042 | css = css_get_next(&mem_cgroup_subsys, id + 1, &root->css, &id); | |
1043 | if (css) { | |
1044 | if (css == &root->css || css_tryget(css)) | |
b2145145 | 1045 | memcg = mem_cgroup_from_css(css); |
9f3a0d09 JW |
1046 | } else |
1047 | id = 0; | |
14067bb3 | 1048 | rcu_read_unlock(); |
14067bb3 | 1049 | |
527a5ec9 JW |
1050 | if (reclaim) { |
1051 | iter->position = id; | |
1052 | if (!css) | |
1053 | iter->generation++; | |
1054 | else if (!prev && memcg) | |
1055 | reclaim->generation = iter->generation; | |
1056 | } | |
9f3a0d09 JW |
1057 | |
1058 | if (prev && !css) | |
1059 | return NULL; | |
1060 | } | |
1061 | return memcg; | |
14067bb3 | 1062 | } |
7d74b06f | 1063 | |
5660048c JW |
1064 | /** |
1065 | * mem_cgroup_iter_break - abort a hierarchy walk prematurely | |
1066 | * @root: hierarchy root | |
1067 | * @prev: last visited hierarchy member as returned by mem_cgroup_iter() | |
1068 | */ | |
1069 | void mem_cgroup_iter_break(struct mem_cgroup *root, | |
1070 | struct mem_cgroup *prev) | |
9f3a0d09 JW |
1071 | { |
1072 | if (!root) | |
1073 | root = root_mem_cgroup; | |
1074 | if (prev && prev != root) | |
1075 | css_put(&prev->css); | |
1076 | } | |
7d74b06f | 1077 | |
9f3a0d09 JW |
1078 | /* |
1079 | * Iteration constructs for visiting all cgroups (under a tree). If | |
1080 | * loops are exited prematurely (break), mem_cgroup_iter_break() must | |
1081 | * be used for reference counting. | |
1082 | */ | |
1083 | #define for_each_mem_cgroup_tree(iter, root) \ | |
527a5ec9 | 1084 | for (iter = mem_cgroup_iter(root, NULL, NULL); \ |
9f3a0d09 | 1085 | iter != NULL; \ |
527a5ec9 | 1086 | iter = mem_cgroup_iter(root, iter, NULL)) |
711d3d2c | 1087 | |
9f3a0d09 | 1088 | #define for_each_mem_cgroup(iter) \ |
527a5ec9 | 1089 | for (iter = mem_cgroup_iter(NULL, NULL, NULL); \ |
9f3a0d09 | 1090 | iter != NULL; \ |
527a5ec9 | 1091 | iter = mem_cgroup_iter(NULL, iter, NULL)) |
14067bb3 | 1092 | |
68ae564b | 1093 | void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) |
456f998e | 1094 | { |
c0ff4b85 | 1095 | struct mem_cgroup *memcg; |
456f998e | 1096 | |
456f998e | 1097 | rcu_read_lock(); |
c0ff4b85 R |
1098 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); |
1099 | if (unlikely(!memcg)) | |
456f998e YH |
1100 | goto out; |
1101 | ||
1102 | switch (idx) { | |
456f998e | 1103 | case PGFAULT: |
0e574a93 JW |
1104 | this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT]); |
1105 | break; | |
1106 | case PGMAJFAULT: | |
1107 | this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT]); | |
456f998e YH |
1108 | break; |
1109 | default: | |
1110 | BUG(); | |
1111 | } | |
1112 | out: | |
1113 | rcu_read_unlock(); | |
1114 | } | |
68ae564b | 1115 | EXPORT_SYMBOL(__mem_cgroup_count_vm_event); |
456f998e | 1116 | |
925b7673 JW |
1117 | /** |
1118 | * mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg | |
1119 | * @zone: zone of the wanted lruvec | |
fa9add64 | 1120 | * @memcg: memcg of the wanted lruvec |
925b7673 JW |
1121 | * |
1122 | * Returns the lru list vector holding pages for the given @zone and | |
1123 | * @mem. This can be the global zone lruvec, if the memory controller | |
1124 | * is disabled. | |
1125 | */ | |
1126 | struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone, | |
1127 | struct mem_cgroup *memcg) | |
1128 | { | |
1129 | struct mem_cgroup_per_zone *mz; | |
bea8c150 | 1130 | struct lruvec *lruvec; |
925b7673 | 1131 | |
bea8c150 HD |
1132 | if (mem_cgroup_disabled()) { |
1133 | lruvec = &zone->lruvec; | |
1134 | goto out; | |
1135 | } | |
925b7673 JW |
1136 | |
1137 | mz = mem_cgroup_zoneinfo(memcg, zone_to_nid(zone), zone_idx(zone)); | |
bea8c150 HD |
1138 | lruvec = &mz->lruvec; |
1139 | out: | |
1140 | /* | |
1141 | * Since a node can be onlined after the mem_cgroup was created, | |
1142 | * we have to be prepared to initialize lruvec->zone here; | |
1143 | * and if offlined then reonlined, we need to reinitialize it. | |
1144 | */ | |
1145 | if (unlikely(lruvec->zone != zone)) | |
1146 | lruvec->zone = zone; | |
1147 | return lruvec; | |
925b7673 JW |
1148 | } |
1149 | ||
08e552c6 KH |
1150 | /* |
1151 | * Following LRU functions are allowed to be used without PCG_LOCK. | |
1152 | * Operations are called by routine of global LRU independently from memcg. | |
1153 | * What we have to take care of here is validness of pc->mem_cgroup. | |
1154 | * | |
1155 | * Changes to pc->mem_cgroup happens when | |
1156 | * 1. charge | |
1157 | * 2. moving account | |
1158 | * In typical case, "charge" is done before add-to-lru. Exception is SwapCache. | |
1159 | * It is added to LRU before charge. | |
1160 | * If PCG_USED bit is not set, page_cgroup is not added to this private LRU. | |
1161 | * When moving account, the page is not on LRU. It's isolated. | |
1162 | */ | |
4f98a2fe | 1163 | |
925b7673 | 1164 | /** |
fa9add64 | 1165 | * mem_cgroup_page_lruvec - return lruvec for adding an lru page |
925b7673 | 1166 | * @page: the page |
fa9add64 | 1167 | * @zone: zone of the page |
925b7673 | 1168 | */ |
fa9add64 | 1169 | struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct zone *zone) |
08e552c6 | 1170 | { |
08e552c6 | 1171 | struct mem_cgroup_per_zone *mz; |
925b7673 JW |
1172 | struct mem_cgroup *memcg; |
1173 | struct page_cgroup *pc; | |
bea8c150 | 1174 | struct lruvec *lruvec; |
6d12e2d8 | 1175 | |
bea8c150 HD |
1176 | if (mem_cgroup_disabled()) { |
1177 | lruvec = &zone->lruvec; | |
1178 | goto out; | |
1179 | } | |
925b7673 | 1180 | |
08e552c6 | 1181 | pc = lookup_page_cgroup(page); |
38c5d72f | 1182 | memcg = pc->mem_cgroup; |
7512102c HD |
1183 | |
1184 | /* | |
fa9add64 | 1185 | * Surreptitiously switch any uncharged offlist page to root: |
7512102c HD |
1186 | * an uncharged page off lru does nothing to secure |
1187 | * its former mem_cgroup from sudden removal. | |
1188 | * | |
1189 | * Our caller holds lru_lock, and PageCgroupUsed is updated | |
1190 | * under page_cgroup lock: between them, they make all uses | |
1191 | * of pc->mem_cgroup safe. | |
1192 | */ | |
fa9add64 | 1193 | if (!PageLRU(page) && !PageCgroupUsed(pc) && memcg != root_mem_cgroup) |
7512102c HD |
1194 | pc->mem_cgroup = memcg = root_mem_cgroup; |
1195 | ||
925b7673 | 1196 | mz = page_cgroup_zoneinfo(memcg, page); |
bea8c150 HD |
1197 | lruvec = &mz->lruvec; |
1198 | out: | |
1199 | /* | |
1200 | * Since a node can be onlined after the mem_cgroup was created, | |
1201 | * we have to be prepared to initialize lruvec->zone here; | |
1202 | * and if offlined then reonlined, we need to reinitialize it. | |
1203 | */ | |
1204 | if (unlikely(lruvec->zone != zone)) | |
1205 | lruvec->zone = zone; | |
1206 | return lruvec; | |
08e552c6 | 1207 | } |
b69408e8 | 1208 | |
925b7673 | 1209 | /** |
fa9add64 HD |
1210 | * mem_cgroup_update_lru_size - account for adding or removing an lru page |
1211 | * @lruvec: mem_cgroup per zone lru vector | |
1212 | * @lru: index of lru list the page is sitting on | |
1213 | * @nr_pages: positive when adding or negative when removing | |
925b7673 | 1214 | * |
fa9add64 HD |
1215 | * This function must be called when a page is added to or removed from an |
1216 | * lru list. | |
3f58a829 | 1217 | */ |
fa9add64 HD |
1218 | void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, |
1219 | int nr_pages) | |
3f58a829 MK |
1220 | { |
1221 | struct mem_cgroup_per_zone *mz; | |
fa9add64 | 1222 | unsigned long *lru_size; |
3f58a829 MK |
1223 | |
1224 | if (mem_cgroup_disabled()) | |
1225 | return; | |
1226 | ||
fa9add64 HD |
1227 | mz = container_of(lruvec, struct mem_cgroup_per_zone, lruvec); |
1228 | lru_size = mz->lru_size + lru; | |
1229 | *lru_size += nr_pages; | |
1230 | VM_BUG_ON((long)(*lru_size) < 0); | |
08e552c6 | 1231 | } |
544122e5 | 1232 | |
3e92041d | 1233 | /* |
c0ff4b85 | 1234 | * Checks whether given mem is same or in the root_mem_cgroup's |
3e92041d MH |
1235 | * hierarchy subtree |
1236 | */ | |
c3ac9a8a JW |
1237 | bool __mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg, |
1238 | struct mem_cgroup *memcg) | |
3e92041d | 1239 | { |
91c63734 JW |
1240 | if (root_memcg == memcg) |
1241 | return true; | |
3a981f48 | 1242 | if (!root_memcg->use_hierarchy || !memcg) |
91c63734 | 1243 | return false; |
c3ac9a8a JW |
1244 | return css_is_ancestor(&memcg->css, &root_memcg->css); |
1245 | } | |
1246 | ||
1247 | static bool mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg, | |
1248 | struct mem_cgroup *memcg) | |
1249 | { | |
1250 | bool ret; | |
1251 | ||
91c63734 | 1252 | rcu_read_lock(); |
c3ac9a8a | 1253 | ret = __mem_cgroup_same_or_subtree(root_memcg, memcg); |
91c63734 JW |
1254 | rcu_read_unlock(); |
1255 | return ret; | |
3e92041d MH |
1256 | } |
1257 | ||
c0ff4b85 | 1258 | int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *memcg) |
4c4a2214 DR |
1259 | { |
1260 | int ret; | |
0b7f569e | 1261 | struct mem_cgroup *curr = NULL; |
158e0a2d | 1262 | struct task_struct *p; |
4c4a2214 | 1263 | |
158e0a2d | 1264 | p = find_lock_task_mm(task); |
de077d22 DR |
1265 | if (p) { |
1266 | curr = try_get_mem_cgroup_from_mm(p->mm); | |
1267 | task_unlock(p); | |
1268 | } else { | |
1269 | /* | |
1270 | * All threads may have already detached their mm's, but the oom | |
1271 | * killer still needs to detect if they have already been oom | |
1272 | * killed to prevent needlessly killing additional tasks. | |
1273 | */ | |
1274 | task_lock(task); | |
1275 | curr = mem_cgroup_from_task(task); | |
1276 | if (curr) | |
1277 | css_get(&curr->css); | |
1278 | task_unlock(task); | |
1279 | } | |
0b7f569e KH |
1280 | if (!curr) |
1281 | return 0; | |
d31f56db | 1282 | /* |
c0ff4b85 | 1283 | * We should check use_hierarchy of "memcg" not "curr". Because checking |
d31f56db | 1284 | * use_hierarchy of "curr" here make this function true if hierarchy is |
c0ff4b85 R |
1285 | * enabled in "curr" and "curr" is a child of "memcg" in *cgroup* |
1286 | * hierarchy(even if use_hierarchy is disabled in "memcg"). | |
d31f56db | 1287 | */ |
c0ff4b85 | 1288 | ret = mem_cgroup_same_or_subtree(memcg, curr); |
0b7f569e | 1289 | css_put(&curr->css); |
4c4a2214 DR |
1290 | return ret; |
1291 | } | |
1292 | ||
c56d5c7d | 1293 | int mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec) |
14797e23 | 1294 | { |
9b272977 | 1295 | unsigned long inactive_ratio; |
14797e23 | 1296 | unsigned long inactive; |
9b272977 | 1297 | unsigned long active; |
c772be93 | 1298 | unsigned long gb; |
14797e23 | 1299 | |
4d7dcca2 HD |
1300 | inactive = mem_cgroup_get_lru_size(lruvec, LRU_INACTIVE_ANON); |
1301 | active = mem_cgroup_get_lru_size(lruvec, LRU_ACTIVE_ANON); | |
14797e23 | 1302 | |
c772be93 KM |
1303 | gb = (inactive + active) >> (30 - PAGE_SHIFT); |
1304 | if (gb) | |
1305 | inactive_ratio = int_sqrt(10 * gb); | |
1306 | else | |
1307 | inactive_ratio = 1; | |
1308 | ||
9b272977 | 1309 | return inactive * inactive_ratio < active; |
14797e23 KM |
1310 | } |
1311 | ||
c56d5c7d | 1312 | int mem_cgroup_inactive_file_is_low(struct lruvec *lruvec) |
56e49d21 RR |
1313 | { |
1314 | unsigned long active; | |
1315 | unsigned long inactive; | |
1316 | ||
4d7dcca2 HD |
1317 | inactive = mem_cgroup_get_lru_size(lruvec, LRU_INACTIVE_FILE); |
1318 | active = mem_cgroup_get_lru_size(lruvec, LRU_ACTIVE_FILE); | |
56e49d21 RR |
1319 | |
1320 | return (active > inactive); | |
1321 | } | |
1322 | ||
6d61ef40 BS |
1323 | #define mem_cgroup_from_res_counter(counter, member) \ |
1324 | container_of(counter, struct mem_cgroup, member) | |
1325 | ||
19942822 | 1326 | /** |
9d11ea9f | 1327 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
dad7557e | 1328 | * @memcg: the memory cgroup |
19942822 | 1329 | * |
9d11ea9f | 1330 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1331 | * pages. |
19942822 | 1332 | */ |
c0ff4b85 | 1333 | static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) |
19942822 | 1334 | { |
9d11ea9f JW |
1335 | unsigned long long margin; |
1336 | ||
c0ff4b85 | 1337 | margin = res_counter_margin(&memcg->res); |
9d11ea9f | 1338 | if (do_swap_account) |
c0ff4b85 | 1339 | margin = min(margin, res_counter_margin(&memcg->memsw)); |
7ec99d62 | 1340 | return margin >> PAGE_SHIFT; |
19942822 JW |
1341 | } |
1342 | ||
1f4c025b | 1343 | int mem_cgroup_swappiness(struct mem_cgroup *memcg) |
a7885eb8 KM |
1344 | { |
1345 | struct cgroup *cgrp = memcg->css.cgroup; | |
a7885eb8 KM |
1346 | |
1347 | /* root ? */ | |
1348 | if (cgrp->parent == NULL) | |
1349 | return vm_swappiness; | |
1350 | ||
bf1ff263 | 1351 | return memcg->swappiness; |
a7885eb8 KM |
1352 | } |
1353 | ||
619d094b KH |
1354 | /* |
1355 | * memcg->moving_account is used for checking possibility that some thread is | |
1356 | * calling move_account(). When a thread on CPU-A starts moving pages under | |
1357 | * a memcg, other threads should check memcg->moving_account under | |
1358 | * rcu_read_lock(), like this: | |
1359 | * | |
1360 | * CPU-A CPU-B | |
1361 | * rcu_read_lock() | |
1362 | * memcg->moving_account+1 if (memcg->mocing_account) | |
1363 | * take heavy locks. | |
1364 | * synchronize_rcu() update something. | |
1365 | * rcu_read_unlock() | |
1366 | * start move here. | |
1367 | */ | |
4331f7d3 KH |
1368 | |
1369 | /* for quick checking without looking up memcg */ | |
1370 | atomic_t memcg_moving __read_mostly; | |
1371 | ||
c0ff4b85 | 1372 | static void mem_cgroup_start_move(struct mem_cgroup *memcg) |
32047e2a | 1373 | { |
4331f7d3 | 1374 | atomic_inc(&memcg_moving); |
619d094b | 1375 | atomic_inc(&memcg->moving_account); |
32047e2a KH |
1376 | synchronize_rcu(); |
1377 | } | |
1378 | ||
c0ff4b85 | 1379 | static void mem_cgroup_end_move(struct mem_cgroup *memcg) |
32047e2a | 1380 | { |
619d094b KH |
1381 | /* |
1382 | * Now, mem_cgroup_clear_mc() may call this function with NULL. | |
1383 | * We check NULL in callee rather than caller. | |
1384 | */ | |
4331f7d3 KH |
1385 | if (memcg) { |
1386 | atomic_dec(&memcg_moving); | |
619d094b | 1387 | atomic_dec(&memcg->moving_account); |
4331f7d3 | 1388 | } |
32047e2a | 1389 | } |
619d094b | 1390 | |
32047e2a KH |
1391 | /* |
1392 | * 2 routines for checking "mem" is under move_account() or not. | |
1393 | * | |
13fd1dd9 AM |
1394 | * mem_cgroup_stolen() - checking whether a cgroup is mc.from or not. This |
1395 | * is used for avoiding races in accounting. If true, | |
32047e2a KH |
1396 | * pc->mem_cgroup may be overwritten. |
1397 | * | |
1398 | * mem_cgroup_under_move() - checking a cgroup is mc.from or mc.to or | |
1399 | * under hierarchy of moving cgroups. This is for | |
1400 | * waiting at hith-memory prressure caused by "move". | |
1401 | */ | |
1402 | ||
13fd1dd9 | 1403 | static bool mem_cgroup_stolen(struct mem_cgroup *memcg) |
32047e2a KH |
1404 | { |
1405 | VM_BUG_ON(!rcu_read_lock_held()); | |
619d094b | 1406 | return atomic_read(&memcg->moving_account) > 0; |
32047e2a | 1407 | } |
4b534334 | 1408 | |
c0ff4b85 | 1409 | static bool mem_cgroup_under_move(struct mem_cgroup *memcg) |
4b534334 | 1410 | { |
2bd9bb20 KH |
1411 | struct mem_cgroup *from; |
1412 | struct mem_cgroup *to; | |
4b534334 | 1413 | bool ret = false; |
2bd9bb20 KH |
1414 | /* |
1415 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1416 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1417 | */ | |
1418 | spin_lock(&mc.lock); | |
1419 | from = mc.from; | |
1420 | to = mc.to; | |
1421 | if (!from) | |
1422 | goto unlock; | |
3e92041d | 1423 | |
c0ff4b85 R |
1424 | ret = mem_cgroup_same_or_subtree(memcg, from) |
1425 | || mem_cgroup_same_or_subtree(memcg, to); | |
2bd9bb20 KH |
1426 | unlock: |
1427 | spin_unlock(&mc.lock); | |
4b534334 KH |
1428 | return ret; |
1429 | } | |
1430 | ||
c0ff4b85 | 1431 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) |
4b534334 KH |
1432 | { |
1433 | if (mc.moving_task && current != mc.moving_task) { | |
c0ff4b85 | 1434 | if (mem_cgroup_under_move(memcg)) { |
4b534334 KH |
1435 | DEFINE_WAIT(wait); |
1436 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1437 | /* moving charge context might have finished. */ | |
1438 | if (mc.moving_task) | |
1439 | schedule(); | |
1440 | finish_wait(&mc.waitq, &wait); | |
1441 | return true; | |
1442 | } | |
1443 | } | |
1444 | return false; | |
1445 | } | |
1446 | ||
312734c0 KH |
1447 | /* |
1448 | * Take this lock when | |
1449 | * - a code tries to modify page's memcg while it's USED. | |
1450 | * - a code tries to modify page state accounting in a memcg. | |
13fd1dd9 | 1451 | * see mem_cgroup_stolen(), too. |
312734c0 KH |
1452 | */ |
1453 | static void move_lock_mem_cgroup(struct mem_cgroup *memcg, | |
1454 | unsigned long *flags) | |
1455 | { | |
1456 | spin_lock_irqsave(&memcg->move_lock, *flags); | |
1457 | } | |
1458 | ||
1459 | static void move_unlock_mem_cgroup(struct mem_cgroup *memcg, | |
1460 | unsigned long *flags) | |
1461 | { | |
1462 | spin_unlock_irqrestore(&memcg->move_lock, *flags); | |
1463 | } | |
1464 | ||
e222432b | 1465 | /** |
6a6135b6 | 1466 | * mem_cgroup_print_oom_info: Called from OOM with tasklist_lock held in read mode. |
e222432b BS |
1467 | * @memcg: The memory cgroup that went over limit |
1468 | * @p: Task that is going to be killed | |
1469 | * | |
1470 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1471 | * enabled | |
1472 | */ | |
1473 | void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) | |
1474 | { | |
1475 | struct cgroup *task_cgrp; | |
1476 | struct cgroup *mem_cgrp; | |
1477 | /* | |
1478 | * Need a buffer in BSS, can't rely on allocations. The code relies | |
1479 | * on the assumption that OOM is serialized for memory controller. | |
1480 | * If this assumption is broken, revisit this code. | |
1481 | */ | |
1482 | static char memcg_name[PATH_MAX]; | |
1483 | int ret; | |
1484 | ||
d31f56db | 1485 | if (!memcg || !p) |
e222432b BS |
1486 | return; |
1487 | ||
e222432b BS |
1488 | rcu_read_lock(); |
1489 | ||
1490 | mem_cgrp = memcg->css.cgroup; | |
1491 | task_cgrp = task_cgroup(p, mem_cgroup_subsys_id); | |
1492 | ||
1493 | ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX); | |
1494 | if (ret < 0) { | |
1495 | /* | |
1496 | * Unfortunately, we are unable to convert to a useful name | |
1497 | * But we'll still print out the usage information | |
1498 | */ | |
1499 | rcu_read_unlock(); | |
1500 | goto done; | |
1501 | } | |
1502 | rcu_read_unlock(); | |
1503 | ||
1504 | printk(KERN_INFO "Task in %s killed", memcg_name); | |
1505 | ||
1506 | rcu_read_lock(); | |
1507 | ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX); | |
1508 | if (ret < 0) { | |
1509 | rcu_read_unlock(); | |
1510 | goto done; | |
1511 | } | |
1512 | rcu_read_unlock(); | |
1513 | ||
1514 | /* | |
1515 | * Continues from above, so we don't need an KERN_ level | |
1516 | */ | |
1517 | printk(KERN_CONT " as a result of limit of %s\n", memcg_name); | |
1518 | done: | |
1519 | ||
1520 | printk(KERN_INFO "memory: usage %llukB, limit %llukB, failcnt %llu\n", | |
1521 | res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, | |
1522 | res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, | |
1523 | res_counter_read_u64(&memcg->res, RES_FAILCNT)); | |
1524 | printk(KERN_INFO "memory+swap: usage %llukB, limit %llukB, " | |
1525 | "failcnt %llu\n", | |
1526 | res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, | |
1527 | res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, | |
1528 | res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); | |
510fc4e1 GC |
1529 | printk(KERN_INFO "kmem: usage %llukB, limit %llukB, failcnt %llu\n", |
1530 | res_counter_read_u64(&memcg->kmem, RES_USAGE) >> 10, | |
1531 | res_counter_read_u64(&memcg->kmem, RES_LIMIT) >> 10, | |
1532 | res_counter_read_u64(&memcg->kmem, RES_FAILCNT)); | |
e222432b BS |
1533 | } |
1534 | ||
81d39c20 KH |
1535 | /* |
1536 | * This function returns the number of memcg under hierarchy tree. Returns | |
1537 | * 1(self count) if no children. | |
1538 | */ | |
c0ff4b85 | 1539 | static int mem_cgroup_count_children(struct mem_cgroup *memcg) |
81d39c20 KH |
1540 | { |
1541 | int num = 0; | |
7d74b06f KH |
1542 | struct mem_cgroup *iter; |
1543 | ||
c0ff4b85 | 1544 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 1545 | num++; |
81d39c20 KH |
1546 | return num; |
1547 | } | |
1548 | ||
a63d83f4 DR |
1549 | /* |
1550 | * Return the memory (and swap, if configured) limit for a memcg. | |
1551 | */ | |
9cbb78bb | 1552 | static u64 mem_cgroup_get_limit(struct mem_cgroup *memcg) |
a63d83f4 DR |
1553 | { |
1554 | u64 limit; | |
a63d83f4 | 1555 | |
f3e8eb70 | 1556 | limit = res_counter_read_u64(&memcg->res, RES_LIMIT); |
f3e8eb70 | 1557 | |
a63d83f4 | 1558 | /* |
9a5a8f19 | 1559 | * Do not consider swap space if we cannot swap due to swappiness |
a63d83f4 | 1560 | */ |
9a5a8f19 MH |
1561 | if (mem_cgroup_swappiness(memcg)) { |
1562 | u64 memsw; | |
1563 | ||
1564 | limit += total_swap_pages << PAGE_SHIFT; | |
1565 | memsw = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
1566 | ||
1567 | /* | |
1568 | * If memsw is finite and limits the amount of swap space | |
1569 | * available to this memcg, return that limit. | |
1570 | */ | |
1571 | limit = min(limit, memsw); | |
1572 | } | |
1573 | ||
1574 | return limit; | |
a63d83f4 DR |
1575 | } |
1576 | ||
19965460 DR |
1577 | static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, |
1578 | int order) | |
9cbb78bb DR |
1579 | { |
1580 | struct mem_cgroup *iter; | |
1581 | unsigned long chosen_points = 0; | |
1582 | unsigned long totalpages; | |
1583 | unsigned int points = 0; | |
1584 | struct task_struct *chosen = NULL; | |
1585 | ||
876aafbf DR |
1586 | /* |
1587 | * If current has a pending SIGKILL, then automatically select it. The | |
1588 | * goal is to allow it to allocate so that it may quickly exit and free | |
1589 | * its memory. | |
1590 | */ | |
1591 | if (fatal_signal_pending(current)) { | |
1592 | set_thread_flag(TIF_MEMDIE); | |
1593 | return; | |
1594 | } | |
1595 | ||
1596 | check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, order, NULL); | |
9cbb78bb DR |
1597 | totalpages = mem_cgroup_get_limit(memcg) >> PAGE_SHIFT ? : 1; |
1598 | for_each_mem_cgroup_tree(iter, memcg) { | |
1599 | struct cgroup *cgroup = iter->css.cgroup; | |
1600 | struct cgroup_iter it; | |
1601 | struct task_struct *task; | |
1602 | ||
1603 | cgroup_iter_start(cgroup, &it); | |
1604 | while ((task = cgroup_iter_next(cgroup, &it))) { | |
1605 | switch (oom_scan_process_thread(task, totalpages, NULL, | |
1606 | false)) { | |
1607 | case OOM_SCAN_SELECT: | |
1608 | if (chosen) | |
1609 | put_task_struct(chosen); | |
1610 | chosen = task; | |
1611 | chosen_points = ULONG_MAX; | |
1612 | get_task_struct(chosen); | |
1613 | /* fall through */ | |
1614 | case OOM_SCAN_CONTINUE: | |
1615 | continue; | |
1616 | case OOM_SCAN_ABORT: | |
1617 | cgroup_iter_end(cgroup, &it); | |
1618 | mem_cgroup_iter_break(memcg, iter); | |
1619 | if (chosen) | |
1620 | put_task_struct(chosen); | |
1621 | return; | |
1622 | case OOM_SCAN_OK: | |
1623 | break; | |
1624 | }; | |
1625 | points = oom_badness(task, memcg, NULL, totalpages); | |
1626 | if (points > chosen_points) { | |
1627 | if (chosen) | |
1628 | put_task_struct(chosen); | |
1629 | chosen = task; | |
1630 | chosen_points = points; | |
1631 | get_task_struct(chosen); | |
1632 | } | |
1633 | } | |
1634 | cgroup_iter_end(cgroup, &it); | |
1635 | } | |
1636 | ||
1637 | if (!chosen) | |
1638 | return; | |
1639 | points = chosen_points * 1000 / totalpages; | |
9cbb78bb DR |
1640 | oom_kill_process(chosen, gfp_mask, order, points, totalpages, memcg, |
1641 | NULL, "Memory cgroup out of memory"); | |
9cbb78bb DR |
1642 | } |
1643 | ||
5660048c JW |
1644 | static unsigned long mem_cgroup_reclaim(struct mem_cgroup *memcg, |
1645 | gfp_t gfp_mask, | |
1646 | unsigned long flags) | |
1647 | { | |
1648 | unsigned long total = 0; | |
1649 | bool noswap = false; | |
1650 | int loop; | |
1651 | ||
1652 | if (flags & MEM_CGROUP_RECLAIM_NOSWAP) | |
1653 | noswap = true; | |
1654 | if (!(flags & MEM_CGROUP_RECLAIM_SHRINK) && memcg->memsw_is_minimum) | |
1655 | noswap = true; | |
1656 | ||
1657 | for (loop = 0; loop < MEM_CGROUP_MAX_RECLAIM_LOOPS; loop++) { | |
1658 | if (loop) | |
1659 | drain_all_stock_async(memcg); | |
1660 | total += try_to_free_mem_cgroup_pages(memcg, gfp_mask, noswap); | |
1661 | /* | |
1662 | * Allow limit shrinkers, which are triggered directly | |
1663 | * by userspace, to catch signals and stop reclaim | |
1664 | * after minimal progress, regardless of the margin. | |
1665 | */ | |
1666 | if (total && (flags & MEM_CGROUP_RECLAIM_SHRINK)) | |
1667 | break; | |
1668 | if (mem_cgroup_margin(memcg)) | |
1669 | break; | |
1670 | /* | |
1671 | * If nothing was reclaimed after two attempts, there | |
1672 | * may be no reclaimable pages in this hierarchy. | |
1673 | */ | |
1674 | if (loop && !total) | |
1675 | break; | |
1676 | } | |
1677 | return total; | |
1678 | } | |
1679 | ||
4d0c066d KH |
1680 | /** |
1681 | * test_mem_cgroup_node_reclaimable | |
dad7557e | 1682 | * @memcg: the target memcg |
4d0c066d KH |
1683 | * @nid: the node ID to be checked. |
1684 | * @noswap : specify true here if the user wants flle only information. | |
1685 | * | |
1686 | * This function returns whether the specified memcg contains any | |
1687 | * reclaimable pages on a node. Returns true if there are any reclaimable | |
1688 | * pages in the node. | |
1689 | */ | |
c0ff4b85 | 1690 | static bool test_mem_cgroup_node_reclaimable(struct mem_cgroup *memcg, |
4d0c066d KH |
1691 | int nid, bool noswap) |
1692 | { | |
c0ff4b85 | 1693 | if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_FILE)) |
4d0c066d KH |
1694 | return true; |
1695 | if (noswap || !total_swap_pages) | |
1696 | return false; | |
c0ff4b85 | 1697 | if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_ANON)) |
4d0c066d KH |
1698 | return true; |
1699 | return false; | |
1700 | ||
1701 | } | |
889976db YH |
1702 | #if MAX_NUMNODES > 1 |
1703 | ||
1704 | /* | |
1705 | * Always updating the nodemask is not very good - even if we have an empty | |
1706 | * list or the wrong list here, we can start from some node and traverse all | |
1707 | * nodes based on the zonelist. So update the list loosely once per 10 secs. | |
1708 | * | |
1709 | */ | |
c0ff4b85 | 1710 | static void mem_cgroup_may_update_nodemask(struct mem_cgroup *memcg) |
889976db YH |
1711 | { |
1712 | int nid; | |
453a9bf3 KH |
1713 | /* |
1714 | * numainfo_events > 0 means there was at least NUMAINFO_EVENTS_TARGET | |
1715 | * pagein/pageout changes since the last update. | |
1716 | */ | |
c0ff4b85 | 1717 | if (!atomic_read(&memcg->numainfo_events)) |
453a9bf3 | 1718 | return; |
c0ff4b85 | 1719 | if (atomic_inc_return(&memcg->numainfo_updating) > 1) |
889976db YH |
1720 | return; |
1721 | ||
889976db | 1722 | /* make a nodemask where this memcg uses memory from */ |
31aaea4a | 1723 | memcg->scan_nodes = node_states[N_MEMORY]; |
889976db | 1724 | |
31aaea4a | 1725 | for_each_node_mask(nid, node_states[N_MEMORY]) { |
889976db | 1726 | |
c0ff4b85 R |
1727 | if (!test_mem_cgroup_node_reclaimable(memcg, nid, false)) |
1728 | node_clear(nid, memcg->scan_nodes); | |
889976db | 1729 | } |
453a9bf3 | 1730 | |
c0ff4b85 R |
1731 | atomic_set(&memcg->numainfo_events, 0); |
1732 | atomic_set(&memcg->numainfo_updating, 0); | |
889976db YH |
1733 | } |
1734 | ||
1735 | /* | |
1736 | * Selecting a node where we start reclaim from. Because what we need is just | |
1737 | * reducing usage counter, start from anywhere is O,K. Considering | |
1738 | * memory reclaim from current node, there are pros. and cons. | |
1739 | * | |
1740 | * Freeing memory from current node means freeing memory from a node which | |
1741 | * we'll use or we've used. So, it may make LRU bad. And if several threads | |
1742 | * hit limits, it will see a contention on a node. But freeing from remote | |
1743 | * node means more costs for memory reclaim because of memory latency. | |
1744 | * | |
1745 | * Now, we use round-robin. Better algorithm is welcomed. | |
1746 | */ | |
c0ff4b85 | 1747 | int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) |
889976db YH |
1748 | { |
1749 | int node; | |
1750 | ||
c0ff4b85 R |
1751 | mem_cgroup_may_update_nodemask(memcg); |
1752 | node = memcg->last_scanned_node; | |
889976db | 1753 | |
c0ff4b85 | 1754 | node = next_node(node, memcg->scan_nodes); |
889976db | 1755 | if (node == MAX_NUMNODES) |
c0ff4b85 | 1756 | node = first_node(memcg->scan_nodes); |
889976db YH |
1757 | /* |
1758 | * We call this when we hit limit, not when pages are added to LRU. | |
1759 | * No LRU may hold pages because all pages are UNEVICTABLE or | |
1760 | * memcg is too small and all pages are not on LRU. In that case, | |
1761 | * we use curret node. | |
1762 | */ | |
1763 | if (unlikely(node == MAX_NUMNODES)) | |
1764 | node = numa_node_id(); | |
1765 | ||
c0ff4b85 | 1766 | memcg->last_scanned_node = node; |
889976db YH |
1767 | return node; |
1768 | } | |
1769 | ||
4d0c066d KH |
1770 | /* |
1771 | * Check all nodes whether it contains reclaimable pages or not. | |
1772 | * For quick scan, we make use of scan_nodes. This will allow us to skip | |
1773 | * unused nodes. But scan_nodes is lazily updated and may not cotain | |
1774 | * enough new information. We need to do double check. | |
1775 | */ | |
6bbda35c | 1776 | static bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) |
4d0c066d KH |
1777 | { |
1778 | int nid; | |
1779 | ||
1780 | /* | |
1781 | * quick check...making use of scan_node. | |
1782 | * We can skip unused nodes. | |
1783 | */ | |
c0ff4b85 R |
1784 | if (!nodes_empty(memcg->scan_nodes)) { |
1785 | for (nid = first_node(memcg->scan_nodes); | |
4d0c066d | 1786 | nid < MAX_NUMNODES; |
c0ff4b85 | 1787 | nid = next_node(nid, memcg->scan_nodes)) { |
4d0c066d | 1788 | |
c0ff4b85 | 1789 | if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap)) |
4d0c066d KH |
1790 | return true; |
1791 | } | |
1792 | } | |
1793 | /* | |
1794 | * Check rest of nodes. | |
1795 | */ | |
31aaea4a | 1796 | for_each_node_state(nid, N_MEMORY) { |
c0ff4b85 | 1797 | if (node_isset(nid, memcg->scan_nodes)) |
4d0c066d | 1798 | continue; |
c0ff4b85 | 1799 | if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap)) |
4d0c066d KH |
1800 | return true; |
1801 | } | |
1802 | return false; | |
1803 | } | |
1804 | ||
889976db | 1805 | #else |
c0ff4b85 | 1806 | int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) |
889976db YH |
1807 | { |
1808 | return 0; | |
1809 | } | |
4d0c066d | 1810 | |
6bbda35c | 1811 | static bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) |
4d0c066d | 1812 | { |
c0ff4b85 | 1813 | return test_mem_cgroup_node_reclaimable(memcg, 0, noswap); |
4d0c066d | 1814 | } |
889976db YH |
1815 | #endif |
1816 | ||
5660048c JW |
1817 | static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, |
1818 | struct zone *zone, | |
1819 | gfp_t gfp_mask, | |
1820 | unsigned long *total_scanned) | |
6d61ef40 | 1821 | { |
9f3a0d09 | 1822 | struct mem_cgroup *victim = NULL; |
5660048c | 1823 | int total = 0; |
04046e1a | 1824 | int loop = 0; |
9d11ea9f | 1825 | unsigned long excess; |
185efc0f | 1826 | unsigned long nr_scanned; |
527a5ec9 JW |
1827 | struct mem_cgroup_reclaim_cookie reclaim = { |
1828 | .zone = zone, | |
1829 | .priority = 0, | |
1830 | }; | |
9d11ea9f | 1831 | |
c0ff4b85 | 1832 | excess = res_counter_soft_limit_excess(&root_memcg->res) >> PAGE_SHIFT; |
04046e1a | 1833 | |
4e416953 | 1834 | while (1) { |
527a5ec9 | 1835 | victim = mem_cgroup_iter(root_memcg, victim, &reclaim); |
9f3a0d09 | 1836 | if (!victim) { |
04046e1a | 1837 | loop++; |
4e416953 BS |
1838 | if (loop >= 2) { |
1839 | /* | |
1840 | * If we have not been able to reclaim | |
1841 | * anything, it might because there are | |
1842 | * no reclaimable pages under this hierarchy | |
1843 | */ | |
5660048c | 1844 | if (!total) |
4e416953 | 1845 | break; |
4e416953 | 1846 | /* |
25985edc | 1847 | * We want to do more targeted reclaim. |
4e416953 BS |
1848 | * excess >> 2 is not to excessive so as to |
1849 | * reclaim too much, nor too less that we keep | |
1850 | * coming back to reclaim from this cgroup | |
1851 | */ | |
1852 | if (total >= (excess >> 2) || | |
9f3a0d09 | 1853 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) |
4e416953 | 1854 | break; |
4e416953 | 1855 | } |
9f3a0d09 | 1856 | continue; |
4e416953 | 1857 | } |
5660048c | 1858 | if (!mem_cgroup_reclaimable(victim, false)) |
6d61ef40 | 1859 | continue; |
5660048c JW |
1860 | total += mem_cgroup_shrink_node_zone(victim, gfp_mask, false, |
1861 | zone, &nr_scanned); | |
1862 | *total_scanned += nr_scanned; | |
1863 | if (!res_counter_soft_limit_excess(&root_memcg->res)) | |
9f3a0d09 | 1864 | break; |
6d61ef40 | 1865 | } |
9f3a0d09 | 1866 | mem_cgroup_iter_break(root_memcg, victim); |
04046e1a | 1867 | return total; |
6d61ef40 BS |
1868 | } |
1869 | ||
867578cb KH |
1870 | /* |
1871 | * Check OOM-Killer is already running under our hierarchy. | |
1872 | * If someone is running, return false. | |
1af8efe9 | 1873 | * Has to be called with memcg_oom_lock |
867578cb | 1874 | */ |
c0ff4b85 | 1875 | static bool mem_cgroup_oom_lock(struct mem_cgroup *memcg) |
867578cb | 1876 | { |
79dfdacc | 1877 | struct mem_cgroup *iter, *failed = NULL; |
a636b327 | 1878 | |
9f3a0d09 | 1879 | for_each_mem_cgroup_tree(iter, memcg) { |
23751be0 | 1880 | if (iter->oom_lock) { |
79dfdacc MH |
1881 | /* |
1882 | * this subtree of our hierarchy is already locked | |
1883 | * so we cannot give a lock. | |
1884 | */ | |
79dfdacc | 1885 | failed = iter; |
9f3a0d09 JW |
1886 | mem_cgroup_iter_break(memcg, iter); |
1887 | break; | |
23751be0 JW |
1888 | } else |
1889 | iter->oom_lock = true; | |
7d74b06f | 1890 | } |
867578cb | 1891 | |
79dfdacc | 1892 | if (!failed) |
23751be0 | 1893 | return true; |
79dfdacc MH |
1894 | |
1895 | /* | |
1896 | * OK, we failed to lock the whole subtree so we have to clean up | |
1897 | * what we set up to the failing subtree | |
1898 | */ | |
9f3a0d09 | 1899 | for_each_mem_cgroup_tree(iter, memcg) { |
79dfdacc | 1900 | if (iter == failed) { |
9f3a0d09 JW |
1901 | mem_cgroup_iter_break(memcg, iter); |
1902 | break; | |
79dfdacc MH |
1903 | } |
1904 | iter->oom_lock = false; | |
1905 | } | |
23751be0 | 1906 | return false; |
a636b327 | 1907 | } |
0b7f569e | 1908 | |
79dfdacc | 1909 | /* |
1af8efe9 | 1910 | * Has to be called with memcg_oom_lock |
79dfdacc | 1911 | */ |
c0ff4b85 | 1912 | static int mem_cgroup_oom_unlock(struct mem_cgroup *memcg) |
0b7f569e | 1913 | { |
7d74b06f KH |
1914 | struct mem_cgroup *iter; |
1915 | ||
c0ff4b85 | 1916 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc MH |
1917 | iter->oom_lock = false; |
1918 | return 0; | |
1919 | } | |
1920 | ||
c0ff4b85 | 1921 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1922 | { |
1923 | struct mem_cgroup *iter; | |
1924 | ||
c0ff4b85 | 1925 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc MH |
1926 | atomic_inc(&iter->under_oom); |
1927 | } | |
1928 | ||
c0ff4b85 | 1929 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1930 | { |
1931 | struct mem_cgroup *iter; | |
1932 | ||
867578cb KH |
1933 | /* |
1934 | * When a new child is created while the hierarchy is under oom, | |
1935 | * mem_cgroup_oom_lock() may not be called. We have to use | |
1936 | * atomic_add_unless() here. | |
1937 | */ | |
c0ff4b85 | 1938 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc | 1939 | atomic_add_unless(&iter->under_oom, -1, 0); |
0b7f569e KH |
1940 | } |
1941 | ||
1af8efe9 | 1942 | static DEFINE_SPINLOCK(memcg_oom_lock); |
867578cb KH |
1943 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1944 | ||
dc98df5a | 1945 | struct oom_wait_info { |
d79154bb | 1946 | struct mem_cgroup *memcg; |
dc98df5a KH |
1947 | wait_queue_t wait; |
1948 | }; | |
1949 | ||
1950 | static int memcg_oom_wake_function(wait_queue_t *wait, | |
1951 | unsigned mode, int sync, void *arg) | |
1952 | { | |
d79154bb HD |
1953 | struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg; |
1954 | struct mem_cgroup *oom_wait_memcg; | |
dc98df5a KH |
1955 | struct oom_wait_info *oom_wait_info; |
1956 | ||
1957 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
d79154bb | 1958 | oom_wait_memcg = oom_wait_info->memcg; |
dc98df5a | 1959 | |
dc98df5a | 1960 | /* |
d79154bb | 1961 | * Both of oom_wait_info->memcg and wake_memcg are stable under us. |
dc98df5a KH |
1962 | * Then we can use css_is_ancestor without taking care of RCU. |
1963 | */ | |
c0ff4b85 R |
1964 | if (!mem_cgroup_same_or_subtree(oom_wait_memcg, wake_memcg) |
1965 | && !mem_cgroup_same_or_subtree(wake_memcg, oom_wait_memcg)) | |
dc98df5a | 1966 | return 0; |
dc98df5a KH |
1967 | return autoremove_wake_function(wait, mode, sync, arg); |
1968 | } | |
1969 | ||
c0ff4b85 | 1970 | static void memcg_wakeup_oom(struct mem_cgroup *memcg) |
dc98df5a | 1971 | { |
c0ff4b85 R |
1972 | /* for filtering, pass "memcg" as argument. */ |
1973 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg); | |
dc98df5a KH |
1974 | } |
1975 | ||
c0ff4b85 | 1976 | static void memcg_oom_recover(struct mem_cgroup *memcg) |
3c11ecf4 | 1977 | { |
c0ff4b85 R |
1978 | if (memcg && atomic_read(&memcg->under_oom)) |
1979 | memcg_wakeup_oom(memcg); | |
3c11ecf4 KH |
1980 | } |
1981 | ||
867578cb KH |
1982 | /* |
1983 | * try to call OOM killer. returns false if we should exit memory-reclaim loop. | |
1984 | */ | |
6bbda35c KS |
1985 | static bool mem_cgroup_handle_oom(struct mem_cgroup *memcg, gfp_t mask, |
1986 | int order) | |
0b7f569e | 1987 | { |
dc98df5a | 1988 | struct oom_wait_info owait; |
3c11ecf4 | 1989 | bool locked, need_to_kill; |
867578cb | 1990 | |
d79154bb | 1991 | owait.memcg = memcg; |
dc98df5a KH |
1992 | owait.wait.flags = 0; |
1993 | owait.wait.func = memcg_oom_wake_function; | |
1994 | owait.wait.private = current; | |
1995 | INIT_LIST_HEAD(&owait.wait.task_list); | |
3c11ecf4 | 1996 | need_to_kill = true; |
c0ff4b85 | 1997 | mem_cgroup_mark_under_oom(memcg); |
79dfdacc | 1998 | |
c0ff4b85 | 1999 | /* At first, try to OOM lock hierarchy under memcg.*/ |
1af8efe9 | 2000 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 2001 | locked = mem_cgroup_oom_lock(memcg); |
867578cb KH |
2002 | /* |
2003 | * Even if signal_pending(), we can't quit charge() loop without | |
2004 | * accounting. So, UNINTERRUPTIBLE is appropriate. But SIGKILL | |
2005 | * under OOM is always welcomed, use TASK_KILLABLE here. | |
2006 | */ | |
3c11ecf4 | 2007 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
c0ff4b85 | 2008 | if (!locked || memcg->oom_kill_disable) |
3c11ecf4 KH |
2009 | need_to_kill = false; |
2010 | if (locked) | |
c0ff4b85 | 2011 | mem_cgroup_oom_notify(memcg); |
1af8efe9 | 2012 | spin_unlock(&memcg_oom_lock); |
867578cb | 2013 | |
3c11ecf4 KH |
2014 | if (need_to_kill) { |
2015 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
e845e199 | 2016 | mem_cgroup_out_of_memory(memcg, mask, order); |
3c11ecf4 | 2017 | } else { |
867578cb | 2018 | schedule(); |
dc98df5a | 2019 | finish_wait(&memcg_oom_waitq, &owait.wait); |
867578cb | 2020 | } |
1af8efe9 | 2021 | spin_lock(&memcg_oom_lock); |
79dfdacc | 2022 | if (locked) |
c0ff4b85 R |
2023 | mem_cgroup_oom_unlock(memcg); |
2024 | memcg_wakeup_oom(memcg); | |
1af8efe9 | 2025 | spin_unlock(&memcg_oom_lock); |
867578cb | 2026 | |
c0ff4b85 | 2027 | mem_cgroup_unmark_under_oom(memcg); |
79dfdacc | 2028 | |
867578cb KH |
2029 | if (test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current)) |
2030 | return false; | |
2031 | /* Give chance to dying process */ | |
715a5ee8 | 2032 | schedule_timeout_uninterruptible(1); |
867578cb | 2033 | return true; |
0b7f569e KH |
2034 | } |
2035 | ||
d69b042f BS |
2036 | /* |
2037 | * Currently used to update mapped file statistics, but the routine can be | |
2038 | * generalized to update other statistics as well. | |
32047e2a KH |
2039 | * |
2040 | * Notes: Race condition | |
2041 | * | |
2042 | * We usually use page_cgroup_lock() for accessing page_cgroup member but | |
2043 | * it tends to be costly. But considering some conditions, we doesn't need | |
2044 | * to do so _always_. | |
2045 | * | |
2046 | * Considering "charge", lock_page_cgroup() is not required because all | |
2047 | * file-stat operations happen after a page is attached to radix-tree. There | |
2048 | * are no race with "charge". | |
2049 | * | |
2050 | * Considering "uncharge", we know that memcg doesn't clear pc->mem_cgroup | |
2051 | * at "uncharge" intentionally. So, we always see valid pc->mem_cgroup even | |
2052 | * if there are race with "uncharge". Statistics itself is properly handled | |
2053 | * by flags. | |
2054 | * | |
2055 | * Considering "move", this is an only case we see a race. To make the race | |
619d094b KH |
2056 | * small, we check mm->moving_account and detect there are possibility of race |
2057 | * If there is, we take a lock. | |
d69b042f | 2058 | */ |
26174efd | 2059 | |
89c06bd5 KH |
2060 | void __mem_cgroup_begin_update_page_stat(struct page *page, |
2061 | bool *locked, unsigned long *flags) | |
2062 | { | |
2063 | struct mem_cgroup *memcg; | |
2064 | struct page_cgroup *pc; | |
2065 | ||
2066 | pc = lookup_page_cgroup(page); | |
2067 | again: | |
2068 | memcg = pc->mem_cgroup; | |
2069 | if (unlikely(!memcg || !PageCgroupUsed(pc))) | |
2070 | return; | |
2071 | /* | |
2072 | * If this memory cgroup is not under account moving, we don't | |
da92c47d | 2073 | * need to take move_lock_mem_cgroup(). Because we already hold |
89c06bd5 | 2074 | * rcu_read_lock(), any calls to move_account will be delayed until |
13fd1dd9 | 2075 | * rcu_read_unlock() if mem_cgroup_stolen() == true. |
89c06bd5 | 2076 | */ |
13fd1dd9 | 2077 | if (!mem_cgroup_stolen(memcg)) |
89c06bd5 KH |
2078 | return; |
2079 | ||
2080 | move_lock_mem_cgroup(memcg, flags); | |
2081 | if (memcg != pc->mem_cgroup || !PageCgroupUsed(pc)) { | |
2082 | move_unlock_mem_cgroup(memcg, flags); | |
2083 | goto again; | |
2084 | } | |
2085 | *locked = true; | |
2086 | } | |
2087 | ||
2088 | void __mem_cgroup_end_update_page_stat(struct page *page, unsigned long *flags) | |
2089 | { | |
2090 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
2091 | ||
2092 | /* | |
2093 | * It's guaranteed that pc->mem_cgroup never changes while | |
2094 | * lock is held because a routine modifies pc->mem_cgroup | |
da92c47d | 2095 | * should take move_lock_mem_cgroup(). |
89c06bd5 KH |
2096 | */ |
2097 | move_unlock_mem_cgroup(pc->mem_cgroup, flags); | |
2098 | } | |
2099 | ||
2a7106f2 GT |
2100 | void mem_cgroup_update_page_stat(struct page *page, |
2101 | enum mem_cgroup_page_stat_item idx, int val) | |
d69b042f | 2102 | { |
c0ff4b85 | 2103 | struct mem_cgroup *memcg; |
32047e2a | 2104 | struct page_cgroup *pc = lookup_page_cgroup(page); |
dbd4ea78 | 2105 | unsigned long uninitialized_var(flags); |
d69b042f | 2106 | |
cfa44946 | 2107 | if (mem_cgroup_disabled()) |
d69b042f | 2108 | return; |
89c06bd5 | 2109 | |
c0ff4b85 R |
2110 | memcg = pc->mem_cgroup; |
2111 | if (unlikely(!memcg || !PageCgroupUsed(pc))) | |
89c06bd5 | 2112 | return; |
26174efd | 2113 | |
26174efd | 2114 | switch (idx) { |
2a7106f2 | 2115 | case MEMCG_NR_FILE_MAPPED: |
2a7106f2 | 2116 | idx = MEM_CGROUP_STAT_FILE_MAPPED; |
26174efd KH |
2117 | break; |
2118 | default: | |
2119 | BUG(); | |
8725d541 | 2120 | } |
d69b042f | 2121 | |
c0ff4b85 | 2122 | this_cpu_add(memcg->stat->count[idx], val); |
d69b042f | 2123 | } |
26174efd | 2124 | |
cdec2e42 KH |
2125 | /* |
2126 | * size of first charge trial. "32" comes from vmscan.c's magic value. | |
2127 | * TODO: maybe necessary to use big numbers in big irons. | |
2128 | */ | |
7ec99d62 | 2129 | #define CHARGE_BATCH 32U |
cdec2e42 KH |
2130 | struct memcg_stock_pcp { |
2131 | struct mem_cgroup *cached; /* this never be root cgroup */ | |
11c9ea4e | 2132 | unsigned int nr_pages; |
cdec2e42 | 2133 | struct work_struct work; |
26fe6168 | 2134 | unsigned long flags; |
a0db00fc | 2135 | #define FLUSHING_CACHED_CHARGE 0 |
cdec2e42 KH |
2136 | }; |
2137 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); | |
9f50fad6 | 2138 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 | 2139 | |
a0956d54 SS |
2140 | /** |
2141 | * consume_stock: Try to consume stocked charge on this cpu. | |
2142 | * @memcg: memcg to consume from. | |
2143 | * @nr_pages: how many pages to charge. | |
2144 | * | |
2145 | * The charges will only happen if @memcg matches the current cpu's memcg | |
2146 | * stock, and at least @nr_pages are available in that stock. Failure to | |
2147 | * service an allocation will refill the stock. | |
2148 | * | |
2149 | * returns true if successful, false otherwise. | |
cdec2e42 | 2150 | */ |
a0956d54 | 2151 | static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
2152 | { |
2153 | struct memcg_stock_pcp *stock; | |
2154 | bool ret = true; | |
2155 | ||
a0956d54 SS |
2156 | if (nr_pages > CHARGE_BATCH) |
2157 | return false; | |
2158 | ||
cdec2e42 | 2159 | stock = &get_cpu_var(memcg_stock); |
a0956d54 SS |
2160 | if (memcg == stock->cached && stock->nr_pages >= nr_pages) |
2161 | stock->nr_pages -= nr_pages; | |
cdec2e42 KH |
2162 | else /* need to call res_counter_charge */ |
2163 | ret = false; | |
2164 | put_cpu_var(memcg_stock); | |
2165 | return ret; | |
2166 | } | |
2167 | ||
2168 | /* | |
2169 | * Returns stocks cached in percpu to res_counter and reset cached information. | |
2170 | */ | |
2171 | static void drain_stock(struct memcg_stock_pcp *stock) | |
2172 | { | |
2173 | struct mem_cgroup *old = stock->cached; | |
2174 | ||
11c9ea4e JW |
2175 | if (stock->nr_pages) { |
2176 | unsigned long bytes = stock->nr_pages * PAGE_SIZE; | |
2177 | ||
2178 | res_counter_uncharge(&old->res, bytes); | |
cdec2e42 | 2179 | if (do_swap_account) |
11c9ea4e JW |
2180 | res_counter_uncharge(&old->memsw, bytes); |
2181 | stock->nr_pages = 0; | |
cdec2e42 KH |
2182 | } |
2183 | stock->cached = NULL; | |
cdec2e42 KH |
2184 | } |
2185 | ||
2186 | /* | |
2187 | * This must be called under preempt disabled or must be called by | |
2188 | * a thread which is pinned to local cpu. | |
2189 | */ | |
2190 | static void drain_local_stock(struct work_struct *dummy) | |
2191 | { | |
2192 | struct memcg_stock_pcp *stock = &__get_cpu_var(memcg_stock); | |
2193 | drain_stock(stock); | |
26fe6168 | 2194 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
cdec2e42 KH |
2195 | } |
2196 | ||
2197 | /* | |
2198 | * Cache charges(val) which is from res_counter, to local per_cpu area. | |
320cc51d | 2199 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 2200 | */ |
c0ff4b85 | 2201 | static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
2202 | { |
2203 | struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock); | |
2204 | ||
c0ff4b85 | 2205 | if (stock->cached != memcg) { /* reset if necessary */ |
cdec2e42 | 2206 | drain_stock(stock); |
c0ff4b85 | 2207 | stock->cached = memcg; |
cdec2e42 | 2208 | } |
11c9ea4e | 2209 | stock->nr_pages += nr_pages; |
cdec2e42 KH |
2210 | put_cpu_var(memcg_stock); |
2211 | } | |
2212 | ||
2213 | /* | |
c0ff4b85 | 2214 | * Drains all per-CPU charge caches for given root_memcg resp. subtree |
d38144b7 MH |
2215 | * of the hierarchy under it. sync flag says whether we should block |
2216 | * until the work is done. | |
cdec2e42 | 2217 | */ |
c0ff4b85 | 2218 | static void drain_all_stock(struct mem_cgroup *root_memcg, bool sync) |
cdec2e42 | 2219 | { |
26fe6168 | 2220 | int cpu, curcpu; |
d38144b7 | 2221 | |
cdec2e42 | 2222 | /* Notify other cpus that system-wide "drain" is running */ |
cdec2e42 | 2223 | get_online_cpus(); |
5af12d0e | 2224 | curcpu = get_cpu(); |
cdec2e42 KH |
2225 | for_each_online_cpu(cpu) { |
2226 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
c0ff4b85 | 2227 | struct mem_cgroup *memcg; |
26fe6168 | 2228 | |
c0ff4b85 R |
2229 | memcg = stock->cached; |
2230 | if (!memcg || !stock->nr_pages) | |
26fe6168 | 2231 | continue; |
c0ff4b85 | 2232 | if (!mem_cgroup_same_or_subtree(root_memcg, memcg)) |
3e92041d | 2233 | continue; |
d1a05b69 MH |
2234 | if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { |
2235 | if (cpu == curcpu) | |
2236 | drain_local_stock(&stock->work); | |
2237 | else | |
2238 | schedule_work_on(cpu, &stock->work); | |
2239 | } | |
cdec2e42 | 2240 | } |
5af12d0e | 2241 | put_cpu(); |
d38144b7 MH |
2242 | |
2243 | if (!sync) | |
2244 | goto out; | |
2245 | ||
2246 | for_each_online_cpu(cpu) { | |
2247 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
9f50fad6 | 2248 | if (test_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) |
d38144b7 MH |
2249 | flush_work(&stock->work); |
2250 | } | |
2251 | out: | |
cdec2e42 | 2252 | put_online_cpus(); |
d38144b7 MH |
2253 | } |
2254 | ||
2255 | /* | |
2256 | * Tries to drain stocked charges in other cpus. This function is asynchronous | |
2257 | * and just put a work per cpu for draining localy on each cpu. Caller can | |
2258 | * expects some charges will be back to res_counter later but cannot wait for | |
2259 | * it. | |
2260 | */ | |
c0ff4b85 | 2261 | static void drain_all_stock_async(struct mem_cgroup *root_memcg) |
d38144b7 | 2262 | { |
9f50fad6 MH |
2263 | /* |
2264 | * If someone calls draining, avoid adding more kworker runs. | |
2265 | */ | |
2266 | if (!mutex_trylock(&percpu_charge_mutex)) | |
2267 | return; | |
c0ff4b85 | 2268 | drain_all_stock(root_memcg, false); |
9f50fad6 | 2269 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2270 | } |
2271 | ||
2272 | /* This is a synchronous drain interface. */ | |
c0ff4b85 | 2273 | static void drain_all_stock_sync(struct mem_cgroup *root_memcg) |
cdec2e42 KH |
2274 | { |
2275 | /* called when force_empty is called */ | |
9f50fad6 | 2276 | mutex_lock(&percpu_charge_mutex); |
c0ff4b85 | 2277 | drain_all_stock(root_memcg, true); |
9f50fad6 | 2278 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2279 | } |
2280 | ||
711d3d2c KH |
2281 | /* |
2282 | * This function drains percpu counter value from DEAD cpu and | |
2283 | * move it to local cpu. Note that this function can be preempted. | |
2284 | */ | |
c0ff4b85 | 2285 | static void mem_cgroup_drain_pcp_counter(struct mem_cgroup *memcg, int cpu) |
711d3d2c KH |
2286 | { |
2287 | int i; | |
2288 | ||
c0ff4b85 | 2289 | spin_lock(&memcg->pcp_counter_lock); |
6104621d | 2290 | for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) { |
c0ff4b85 | 2291 | long x = per_cpu(memcg->stat->count[i], cpu); |
711d3d2c | 2292 | |
c0ff4b85 R |
2293 | per_cpu(memcg->stat->count[i], cpu) = 0; |
2294 | memcg->nocpu_base.count[i] += x; | |
711d3d2c | 2295 | } |
e9f8974f | 2296 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) { |
c0ff4b85 | 2297 | unsigned long x = per_cpu(memcg->stat->events[i], cpu); |
e9f8974f | 2298 | |
c0ff4b85 R |
2299 | per_cpu(memcg->stat->events[i], cpu) = 0; |
2300 | memcg->nocpu_base.events[i] += x; | |
e9f8974f | 2301 | } |
c0ff4b85 | 2302 | spin_unlock(&memcg->pcp_counter_lock); |
711d3d2c KH |
2303 | } |
2304 | ||
2305 | static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, | |
cdec2e42 KH |
2306 | unsigned long action, |
2307 | void *hcpu) | |
2308 | { | |
2309 | int cpu = (unsigned long)hcpu; | |
2310 | struct memcg_stock_pcp *stock; | |
711d3d2c | 2311 | struct mem_cgroup *iter; |
cdec2e42 | 2312 | |
619d094b | 2313 | if (action == CPU_ONLINE) |
1489ebad | 2314 | return NOTIFY_OK; |
1489ebad | 2315 | |
d833049b | 2316 | if (action != CPU_DEAD && action != CPU_DEAD_FROZEN) |
cdec2e42 | 2317 | return NOTIFY_OK; |
711d3d2c | 2318 | |
9f3a0d09 | 2319 | for_each_mem_cgroup(iter) |
711d3d2c KH |
2320 | mem_cgroup_drain_pcp_counter(iter, cpu); |
2321 | ||
cdec2e42 KH |
2322 | stock = &per_cpu(memcg_stock, cpu); |
2323 | drain_stock(stock); | |
2324 | return NOTIFY_OK; | |
2325 | } | |
2326 | ||
4b534334 KH |
2327 | |
2328 | /* See __mem_cgroup_try_charge() for details */ | |
2329 | enum { | |
2330 | CHARGE_OK, /* success */ | |
2331 | CHARGE_RETRY, /* need to retry but retry is not bad */ | |
2332 | CHARGE_NOMEM, /* we can't do more. return -ENOMEM */ | |
2333 | CHARGE_WOULDBLOCK, /* GFP_WAIT wasn't set and no enough res. */ | |
2334 | CHARGE_OOM_DIE, /* the current is killed because of OOM */ | |
2335 | }; | |
2336 | ||
c0ff4b85 | 2337 | static int mem_cgroup_do_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, |
4c9c5359 SS |
2338 | unsigned int nr_pages, unsigned int min_pages, |
2339 | bool oom_check) | |
4b534334 | 2340 | { |
7ec99d62 | 2341 | unsigned long csize = nr_pages * PAGE_SIZE; |
4b534334 KH |
2342 | struct mem_cgroup *mem_over_limit; |
2343 | struct res_counter *fail_res; | |
2344 | unsigned long flags = 0; | |
2345 | int ret; | |
2346 | ||
c0ff4b85 | 2347 | ret = res_counter_charge(&memcg->res, csize, &fail_res); |
4b534334 KH |
2348 | |
2349 | if (likely(!ret)) { | |
2350 | if (!do_swap_account) | |
2351 | return CHARGE_OK; | |
c0ff4b85 | 2352 | ret = res_counter_charge(&memcg->memsw, csize, &fail_res); |
4b534334 KH |
2353 | if (likely(!ret)) |
2354 | return CHARGE_OK; | |
2355 | ||
c0ff4b85 | 2356 | res_counter_uncharge(&memcg->res, csize); |
4b534334 KH |
2357 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw); |
2358 | flags |= MEM_CGROUP_RECLAIM_NOSWAP; | |
2359 | } else | |
2360 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, res); | |
9221edb7 | 2361 | /* |
9221edb7 JW |
2362 | * Never reclaim on behalf of optional batching, retry with a |
2363 | * single page instead. | |
2364 | */ | |
4c9c5359 | 2365 | if (nr_pages > min_pages) |
4b534334 KH |
2366 | return CHARGE_RETRY; |
2367 | ||
2368 | if (!(gfp_mask & __GFP_WAIT)) | |
2369 | return CHARGE_WOULDBLOCK; | |
2370 | ||
4c9c5359 SS |
2371 | if (gfp_mask & __GFP_NORETRY) |
2372 | return CHARGE_NOMEM; | |
2373 | ||
5660048c | 2374 | ret = mem_cgroup_reclaim(mem_over_limit, gfp_mask, flags); |
7ec99d62 | 2375 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
19942822 | 2376 | return CHARGE_RETRY; |
4b534334 | 2377 | /* |
19942822 JW |
2378 | * Even though the limit is exceeded at this point, reclaim |
2379 | * may have been able to free some pages. Retry the charge | |
2380 | * before killing the task. | |
2381 | * | |
2382 | * Only for regular pages, though: huge pages are rather | |
2383 | * unlikely to succeed so close to the limit, and we fall back | |
2384 | * to regular pages anyway in case of failure. | |
4b534334 | 2385 | */ |
4c9c5359 | 2386 | if (nr_pages <= (1 << PAGE_ALLOC_COSTLY_ORDER) && ret) |
4b534334 KH |
2387 | return CHARGE_RETRY; |
2388 | ||
2389 | /* | |
2390 | * At task move, charge accounts can be doubly counted. So, it's | |
2391 | * better to wait until the end of task_move if something is going on. | |
2392 | */ | |
2393 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2394 | return CHARGE_RETRY; | |
2395 | ||
2396 | /* If we don't need to call oom-killer at el, return immediately */ | |
2397 | if (!oom_check) | |
2398 | return CHARGE_NOMEM; | |
2399 | /* check OOM */ | |
e845e199 | 2400 | if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask, get_order(csize))) |
4b534334 KH |
2401 | return CHARGE_OOM_DIE; |
2402 | ||
2403 | return CHARGE_RETRY; | |
2404 | } | |
2405 | ||
f817ed48 | 2406 | /* |
38c5d72f KH |
2407 | * __mem_cgroup_try_charge() does |
2408 | * 1. detect memcg to be charged against from passed *mm and *ptr, | |
2409 | * 2. update res_counter | |
2410 | * 3. call memory reclaim if necessary. | |
2411 | * | |
2412 | * In some special case, if the task is fatal, fatal_signal_pending() or | |
2413 | * has TIF_MEMDIE, this function returns -EINTR while writing root_mem_cgroup | |
2414 | * to *ptr. There are two reasons for this. 1: fatal threads should quit as soon | |
2415 | * as possible without any hazards. 2: all pages should have a valid | |
2416 | * pc->mem_cgroup. If mm is NULL and the caller doesn't pass a valid memcg | |
2417 | * pointer, that is treated as a charge to root_mem_cgroup. | |
2418 | * | |
2419 | * So __mem_cgroup_try_charge() will return | |
2420 | * 0 ... on success, filling *ptr with a valid memcg pointer. | |
2421 | * -ENOMEM ... charge failure because of resource limits. | |
2422 | * -EINTR ... if thread is fatal. *ptr is filled with root_mem_cgroup. | |
2423 | * | |
2424 | * Unlike the exported interface, an "oom" parameter is added. if oom==true, | |
2425 | * the oom-killer can be invoked. | |
8a9f3ccd | 2426 | */ |
f817ed48 | 2427 | static int __mem_cgroup_try_charge(struct mm_struct *mm, |
ec168510 | 2428 | gfp_t gfp_mask, |
7ec99d62 | 2429 | unsigned int nr_pages, |
c0ff4b85 | 2430 | struct mem_cgroup **ptr, |
7ec99d62 | 2431 | bool oom) |
8a9f3ccd | 2432 | { |
7ec99d62 | 2433 | unsigned int batch = max(CHARGE_BATCH, nr_pages); |
4b534334 | 2434 | int nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; |
c0ff4b85 | 2435 | struct mem_cgroup *memcg = NULL; |
4b534334 | 2436 | int ret; |
a636b327 | 2437 | |
867578cb KH |
2438 | /* |
2439 | * Unlike gloval-vm's OOM-kill, we're not in memory shortage | |
2440 | * in system level. So, allow to go ahead dying process in addition to | |
2441 | * MEMDIE process. | |
2442 | */ | |
2443 | if (unlikely(test_thread_flag(TIF_MEMDIE) | |
2444 | || fatal_signal_pending(current))) | |
2445 | goto bypass; | |
a636b327 | 2446 | |
8a9f3ccd | 2447 | /* |
3be91277 HD |
2448 | * We always charge the cgroup the mm_struct belongs to. |
2449 | * The mm_struct's mem_cgroup changes on task migration if the | |
8a9f3ccd | 2450 | * thread group leader migrates. It's possible that mm is not |
24467cac | 2451 | * set, if so charge the root memcg (happens for pagecache usage). |
8a9f3ccd | 2452 | */ |
c0ff4b85 | 2453 | if (!*ptr && !mm) |
38c5d72f | 2454 | *ptr = root_mem_cgroup; |
f75ca962 | 2455 | again: |
c0ff4b85 R |
2456 | if (*ptr) { /* css should be a valid one */ |
2457 | memcg = *ptr; | |
c0ff4b85 | 2458 | if (mem_cgroup_is_root(memcg)) |
f75ca962 | 2459 | goto done; |
a0956d54 | 2460 | if (consume_stock(memcg, nr_pages)) |
f75ca962 | 2461 | goto done; |
c0ff4b85 | 2462 | css_get(&memcg->css); |
4b534334 | 2463 | } else { |
f75ca962 | 2464 | struct task_struct *p; |
54595fe2 | 2465 | |
f75ca962 KH |
2466 | rcu_read_lock(); |
2467 | p = rcu_dereference(mm->owner); | |
f75ca962 | 2468 | /* |
ebb76ce1 | 2469 | * Because we don't have task_lock(), "p" can exit. |
c0ff4b85 | 2470 | * In that case, "memcg" can point to root or p can be NULL with |
ebb76ce1 KH |
2471 | * race with swapoff. Then, we have small risk of mis-accouning. |
2472 | * But such kind of mis-account by race always happens because | |
2473 | * we don't have cgroup_mutex(). It's overkill and we allo that | |
2474 | * small race, here. | |
2475 | * (*) swapoff at el will charge against mm-struct not against | |
2476 | * task-struct. So, mm->owner can be NULL. | |
f75ca962 | 2477 | */ |
c0ff4b85 | 2478 | memcg = mem_cgroup_from_task(p); |
38c5d72f KH |
2479 | if (!memcg) |
2480 | memcg = root_mem_cgroup; | |
2481 | if (mem_cgroup_is_root(memcg)) { | |
f75ca962 KH |
2482 | rcu_read_unlock(); |
2483 | goto done; | |
2484 | } | |
a0956d54 | 2485 | if (consume_stock(memcg, nr_pages)) { |
f75ca962 KH |
2486 | /* |
2487 | * It seems dagerous to access memcg without css_get(). | |
2488 | * But considering how consume_stok works, it's not | |
2489 | * necessary. If consume_stock success, some charges | |
2490 | * from this memcg are cached on this cpu. So, we | |
2491 | * don't need to call css_get()/css_tryget() before | |
2492 | * calling consume_stock(). | |
2493 | */ | |
2494 | rcu_read_unlock(); | |
2495 | goto done; | |
2496 | } | |
2497 | /* after here, we may be blocked. we need to get refcnt */ | |
c0ff4b85 | 2498 | if (!css_tryget(&memcg->css)) { |
f75ca962 KH |
2499 | rcu_read_unlock(); |
2500 | goto again; | |
2501 | } | |
2502 | rcu_read_unlock(); | |
2503 | } | |
8a9f3ccd | 2504 | |
4b534334 KH |
2505 | do { |
2506 | bool oom_check; | |
7a81b88c | 2507 | |
4b534334 | 2508 | /* If killed, bypass charge */ |
f75ca962 | 2509 | if (fatal_signal_pending(current)) { |
c0ff4b85 | 2510 | css_put(&memcg->css); |
4b534334 | 2511 | goto bypass; |
f75ca962 | 2512 | } |
6d61ef40 | 2513 | |
4b534334 KH |
2514 | oom_check = false; |
2515 | if (oom && !nr_oom_retries) { | |
2516 | oom_check = true; | |
2517 | nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
cdec2e42 | 2518 | } |
66e1707b | 2519 | |
4c9c5359 SS |
2520 | ret = mem_cgroup_do_charge(memcg, gfp_mask, batch, nr_pages, |
2521 | oom_check); | |
4b534334 KH |
2522 | switch (ret) { |
2523 | case CHARGE_OK: | |
2524 | break; | |
2525 | case CHARGE_RETRY: /* not in OOM situation but retry */ | |
7ec99d62 | 2526 | batch = nr_pages; |
c0ff4b85 R |
2527 | css_put(&memcg->css); |
2528 | memcg = NULL; | |
f75ca962 | 2529 | goto again; |
4b534334 | 2530 | case CHARGE_WOULDBLOCK: /* !__GFP_WAIT */ |
c0ff4b85 | 2531 | css_put(&memcg->css); |
4b534334 KH |
2532 | goto nomem; |
2533 | case CHARGE_NOMEM: /* OOM routine works */ | |
f75ca962 | 2534 | if (!oom) { |
c0ff4b85 | 2535 | css_put(&memcg->css); |
867578cb | 2536 | goto nomem; |
f75ca962 | 2537 | } |
4b534334 KH |
2538 | /* If oom, we never return -ENOMEM */ |
2539 | nr_oom_retries--; | |
2540 | break; | |
2541 | case CHARGE_OOM_DIE: /* Killed by OOM Killer */ | |
c0ff4b85 | 2542 | css_put(&memcg->css); |
867578cb | 2543 | goto bypass; |
66e1707b | 2544 | } |
4b534334 KH |
2545 | } while (ret != CHARGE_OK); |
2546 | ||
7ec99d62 | 2547 | if (batch > nr_pages) |
c0ff4b85 R |
2548 | refill_stock(memcg, batch - nr_pages); |
2549 | css_put(&memcg->css); | |
0c3e73e8 | 2550 | done: |
c0ff4b85 | 2551 | *ptr = memcg; |
7a81b88c KH |
2552 | return 0; |
2553 | nomem: | |
c0ff4b85 | 2554 | *ptr = NULL; |
7a81b88c | 2555 | return -ENOMEM; |
867578cb | 2556 | bypass: |
38c5d72f KH |
2557 | *ptr = root_mem_cgroup; |
2558 | return -EINTR; | |
7a81b88c | 2559 | } |
8a9f3ccd | 2560 | |
a3032a2c DN |
2561 | /* |
2562 | * Somemtimes we have to undo a charge we got by try_charge(). | |
2563 | * This function is for that and do uncharge, put css's refcnt. | |
2564 | * gotten by try_charge(). | |
2565 | */ | |
c0ff4b85 | 2566 | static void __mem_cgroup_cancel_charge(struct mem_cgroup *memcg, |
e7018b8d | 2567 | unsigned int nr_pages) |
a3032a2c | 2568 | { |
c0ff4b85 | 2569 | if (!mem_cgroup_is_root(memcg)) { |
e7018b8d JW |
2570 | unsigned long bytes = nr_pages * PAGE_SIZE; |
2571 | ||
c0ff4b85 | 2572 | res_counter_uncharge(&memcg->res, bytes); |
a3032a2c | 2573 | if (do_swap_account) |
c0ff4b85 | 2574 | res_counter_uncharge(&memcg->memsw, bytes); |
a3032a2c | 2575 | } |
854ffa8d DN |
2576 | } |
2577 | ||
d01dd17f KH |
2578 | /* |
2579 | * Cancel chrages in this cgroup....doesn't propagate to parent cgroup. | |
2580 | * This is useful when moving usage to parent cgroup. | |
2581 | */ | |
2582 | static void __mem_cgroup_cancel_local_charge(struct mem_cgroup *memcg, | |
2583 | unsigned int nr_pages) | |
2584 | { | |
2585 | unsigned long bytes = nr_pages * PAGE_SIZE; | |
2586 | ||
2587 | if (mem_cgroup_is_root(memcg)) | |
2588 | return; | |
2589 | ||
2590 | res_counter_uncharge_until(&memcg->res, memcg->res.parent, bytes); | |
2591 | if (do_swap_account) | |
2592 | res_counter_uncharge_until(&memcg->memsw, | |
2593 | memcg->memsw.parent, bytes); | |
2594 | } | |
2595 | ||
a3b2d692 KH |
2596 | /* |
2597 | * A helper function to get mem_cgroup from ID. must be called under | |
e9316080 TH |
2598 | * rcu_read_lock(). The caller is responsible for calling css_tryget if |
2599 | * the mem_cgroup is used for charging. (dropping refcnt from swap can be | |
2600 | * called against removed memcg.) | |
a3b2d692 KH |
2601 | */ |
2602 | static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) | |
2603 | { | |
2604 | struct cgroup_subsys_state *css; | |
2605 | ||
2606 | /* ID 0 is unused ID */ | |
2607 | if (!id) | |
2608 | return NULL; | |
2609 | css = css_lookup(&mem_cgroup_subsys, id); | |
2610 | if (!css) | |
2611 | return NULL; | |
b2145145 | 2612 | return mem_cgroup_from_css(css); |
a3b2d692 KH |
2613 | } |
2614 | ||
e42d9d5d | 2615 | struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) |
b5a84319 | 2616 | { |
c0ff4b85 | 2617 | struct mem_cgroup *memcg = NULL; |
3c776e64 | 2618 | struct page_cgroup *pc; |
a3b2d692 | 2619 | unsigned short id; |
b5a84319 KH |
2620 | swp_entry_t ent; |
2621 | ||
3c776e64 DN |
2622 | VM_BUG_ON(!PageLocked(page)); |
2623 | ||
3c776e64 | 2624 | pc = lookup_page_cgroup(page); |
c0bd3f63 | 2625 | lock_page_cgroup(pc); |
a3b2d692 | 2626 | if (PageCgroupUsed(pc)) { |
c0ff4b85 R |
2627 | memcg = pc->mem_cgroup; |
2628 | if (memcg && !css_tryget(&memcg->css)) | |
2629 | memcg = NULL; | |
e42d9d5d | 2630 | } else if (PageSwapCache(page)) { |
3c776e64 | 2631 | ent.val = page_private(page); |
9fb4b7cc | 2632 | id = lookup_swap_cgroup_id(ent); |
a3b2d692 | 2633 | rcu_read_lock(); |
c0ff4b85 R |
2634 | memcg = mem_cgroup_lookup(id); |
2635 | if (memcg && !css_tryget(&memcg->css)) | |
2636 | memcg = NULL; | |
a3b2d692 | 2637 | rcu_read_unlock(); |
3c776e64 | 2638 | } |
c0bd3f63 | 2639 | unlock_page_cgroup(pc); |
c0ff4b85 | 2640 | return memcg; |
b5a84319 KH |
2641 | } |
2642 | ||
c0ff4b85 | 2643 | static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, |
5564e88b | 2644 | struct page *page, |
7ec99d62 | 2645 | unsigned int nr_pages, |
9ce70c02 HD |
2646 | enum charge_type ctype, |
2647 | bool lrucare) | |
7a81b88c | 2648 | { |
ce587e65 | 2649 | struct page_cgroup *pc = lookup_page_cgroup(page); |
9ce70c02 | 2650 | struct zone *uninitialized_var(zone); |
fa9add64 | 2651 | struct lruvec *lruvec; |
9ce70c02 | 2652 | bool was_on_lru = false; |
b2402857 | 2653 | bool anon; |
9ce70c02 | 2654 | |
ca3e0214 | 2655 | lock_page_cgroup(pc); |
90deb788 | 2656 | VM_BUG_ON(PageCgroupUsed(pc)); |
ca3e0214 KH |
2657 | /* |
2658 | * we don't need page_cgroup_lock about tail pages, becase they are not | |
2659 | * accessed by any other context at this point. | |
2660 | */ | |
9ce70c02 HD |
2661 | |
2662 | /* | |
2663 | * In some cases, SwapCache and FUSE(splice_buf->radixtree), the page | |
2664 | * may already be on some other mem_cgroup's LRU. Take care of it. | |
2665 | */ | |
2666 | if (lrucare) { | |
2667 | zone = page_zone(page); | |
2668 | spin_lock_irq(&zone->lru_lock); | |
2669 | if (PageLRU(page)) { | |
fa9add64 | 2670 | lruvec = mem_cgroup_zone_lruvec(zone, pc->mem_cgroup); |
9ce70c02 | 2671 | ClearPageLRU(page); |
fa9add64 | 2672 | del_page_from_lru_list(page, lruvec, page_lru(page)); |
9ce70c02 HD |
2673 | was_on_lru = true; |
2674 | } | |
2675 | } | |
2676 | ||
c0ff4b85 | 2677 | pc->mem_cgroup = memcg; |
261fb61a KH |
2678 | /* |
2679 | * We access a page_cgroup asynchronously without lock_page_cgroup(). | |
2680 | * Especially when a page_cgroup is taken from a page, pc->mem_cgroup | |
2681 | * is accessed after testing USED bit. To make pc->mem_cgroup visible | |
2682 | * before USED bit, we need memory barrier here. | |
2683 | * See mem_cgroup_add_lru_list(), etc. | |
2684 | */ | |
08e552c6 | 2685 | smp_wmb(); |
b2402857 | 2686 | SetPageCgroupUsed(pc); |
3be91277 | 2687 | |
9ce70c02 HD |
2688 | if (lrucare) { |
2689 | if (was_on_lru) { | |
fa9add64 | 2690 | lruvec = mem_cgroup_zone_lruvec(zone, pc->mem_cgroup); |
9ce70c02 HD |
2691 | VM_BUG_ON(PageLRU(page)); |
2692 | SetPageLRU(page); | |
fa9add64 | 2693 | add_page_to_lru_list(page, lruvec, page_lru(page)); |
9ce70c02 HD |
2694 | } |
2695 | spin_unlock_irq(&zone->lru_lock); | |
2696 | } | |
2697 | ||
41326c17 | 2698 | if (ctype == MEM_CGROUP_CHARGE_TYPE_ANON) |
b2402857 KH |
2699 | anon = true; |
2700 | else | |
2701 | anon = false; | |
2702 | ||
2703 | mem_cgroup_charge_statistics(memcg, anon, nr_pages); | |
52d4b9ac | 2704 | unlock_page_cgroup(pc); |
9ce70c02 | 2705 | |
430e4863 KH |
2706 | /* |
2707 | * "charge_statistics" updated event counter. Then, check it. | |
2708 | * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree. | |
2709 | * if they exceeds softlimit. | |
2710 | */ | |
c0ff4b85 | 2711 | memcg_check_events(memcg, page); |
7a81b88c | 2712 | } |
66e1707b | 2713 | |
7ae1e1d0 GC |
2714 | #ifdef CONFIG_MEMCG_KMEM |
2715 | static inline bool memcg_can_account_kmem(struct mem_cgroup *memcg) | |
2716 | { | |
2717 | return !mem_cgroup_disabled() && !mem_cgroup_is_root(memcg) && | |
2718 | (memcg->kmem_account_flags & KMEM_ACCOUNTED_MASK); | |
2719 | } | |
2720 | ||
2721 | static int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp, u64 size) | |
2722 | { | |
2723 | struct res_counter *fail_res; | |
2724 | struct mem_cgroup *_memcg; | |
2725 | int ret = 0; | |
2726 | bool may_oom; | |
2727 | ||
2728 | ret = res_counter_charge(&memcg->kmem, size, &fail_res); | |
2729 | if (ret) | |
2730 | return ret; | |
2731 | ||
2732 | /* | |
2733 | * Conditions under which we can wait for the oom_killer. Those are | |
2734 | * the same conditions tested by the core page allocator | |
2735 | */ | |
2736 | may_oom = (gfp & __GFP_FS) && !(gfp & __GFP_NORETRY); | |
2737 | ||
2738 | _memcg = memcg; | |
2739 | ret = __mem_cgroup_try_charge(NULL, gfp, size >> PAGE_SHIFT, | |
2740 | &_memcg, may_oom); | |
2741 | ||
2742 | if (ret == -EINTR) { | |
2743 | /* | |
2744 | * __mem_cgroup_try_charge() chosed to bypass to root due to | |
2745 | * OOM kill or fatal signal. Since our only options are to | |
2746 | * either fail the allocation or charge it to this cgroup, do | |
2747 | * it as a temporary condition. But we can't fail. From a | |
2748 | * kmem/slab perspective, the cache has already been selected, | |
2749 | * by mem_cgroup_kmem_get_cache(), so it is too late to change | |
2750 | * our minds. | |
2751 | * | |
2752 | * This condition will only trigger if the task entered | |
2753 | * memcg_charge_kmem in a sane state, but was OOM-killed during | |
2754 | * __mem_cgroup_try_charge() above. Tasks that were already | |
2755 | * dying when the allocation triggers should have been already | |
2756 | * directed to the root cgroup in memcontrol.h | |
2757 | */ | |
2758 | res_counter_charge_nofail(&memcg->res, size, &fail_res); | |
2759 | if (do_swap_account) | |
2760 | res_counter_charge_nofail(&memcg->memsw, size, | |
2761 | &fail_res); | |
2762 | ret = 0; | |
2763 | } else if (ret) | |
2764 | res_counter_uncharge(&memcg->kmem, size); | |
2765 | ||
2766 | return ret; | |
2767 | } | |
2768 | ||
2769 | static void memcg_uncharge_kmem(struct mem_cgroup *memcg, u64 size) | |
2770 | { | |
7ae1e1d0 GC |
2771 | res_counter_uncharge(&memcg->res, size); |
2772 | if (do_swap_account) | |
2773 | res_counter_uncharge(&memcg->memsw, size); | |
7de37682 GC |
2774 | |
2775 | /* Not down to 0 */ | |
2776 | if (res_counter_uncharge(&memcg->kmem, size)) | |
2777 | return; | |
2778 | ||
2779 | if (memcg_kmem_test_and_clear_dead(memcg)) | |
2780 | mem_cgroup_put(memcg); | |
7ae1e1d0 GC |
2781 | } |
2782 | ||
2783 | /* | |
2784 | * We need to verify if the allocation against current->mm->owner's memcg is | |
2785 | * possible for the given order. But the page is not allocated yet, so we'll | |
2786 | * need a further commit step to do the final arrangements. | |
2787 | * | |
2788 | * It is possible for the task to switch cgroups in this mean time, so at | |
2789 | * commit time, we can't rely on task conversion any longer. We'll then use | |
2790 | * the handle argument to return to the caller which cgroup we should commit | |
2791 | * against. We could also return the memcg directly and avoid the pointer | |
2792 | * passing, but a boolean return value gives better semantics considering | |
2793 | * the compiled-out case as well. | |
2794 | * | |
2795 | * Returning true means the allocation is possible. | |
2796 | */ | |
2797 | bool | |
2798 | __memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **_memcg, int order) | |
2799 | { | |
2800 | struct mem_cgroup *memcg; | |
2801 | int ret; | |
2802 | ||
2803 | *_memcg = NULL; | |
2804 | memcg = try_get_mem_cgroup_from_mm(current->mm); | |
2805 | ||
2806 | /* | |
2807 | * very rare case described in mem_cgroup_from_task. Unfortunately there | |
2808 | * isn't much we can do without complicating this too much, and it would | |
2809 | * be gfp-dependent anyway. Just let it go | |
2810 | */ | |
2811 | if (unlikely(!memcg)) | |
2812 | return true; | |
2813 | ||
2814 | if (!memcg_can_account_kmem(memcg)) { | |
2815 | css_put(&memcg->css); | |
2816 | return true; | |
2817 | } | |
2818 | ||
7ae1e1d0 GC |
2819 | ret = memcg_charge_kmem(memcg, gfp, PAGE_SIZE << order); |
2820 | if (!ret) | |
2821 | *_memcg = memcg; | |
7ae1e1d0 GC |
2822 | |
2823 | css_put(&memcg->css); | |
2824 | return (ret == 0); | |
2825 | } | |
2826 | ||
2827 | void __memcg_kmem_commit_charge(struct page *page, struct mem_cgroup *memcg, | |
2828 | int order) | |
2829 | { | |
2830 | struct page_cgroup *pc; | |
2831 | ||
2832 | VM_BUG_ON(mem_cgroup_is_root(memcg)); | |
2833 | ||
2834 | /* The page allocation failed. Revert */ | |
2835 | if (!page) { | |
2836 | memcg_uncharge_kmem(memcg, PAGE_SIZE << order); | |
7ae1e1d0 GC |
2837 | return; |
2838 | } | |
2839 | ||
2840 | pc = lookup_page_cgroup(page); | |
2841 | lock_page_cgroup(pc); | |
2842 | pc->mem_cgroup = memcg; | |
2843 | SetPageCgroupUsed(pc); | |
2844 | unlock_page_cgroup(pc); | |
2845 | } | |
2846 | ||
2847 | void __memcg_kmem_uncharge_pages(struct page *page, int order) | |
2848 | { | |
2849 | struct mem_cgroup *memcg = NULL; | |
2850 | struct page_cgroup *pc; | |
2851 | ||
2852 | ||
2853 | pc = lookup_page_cgroup(page); | |
2854 | /* | |
2855 | * Fast unlocked return. Theoretically might have changed, have to | |
2856 | * check again after locking. | |
2857 | */ | |
2858 | if (!PageCgroupUsed(pc)) | |
2859 | return; | |
2860 | ||
2861 | lock_page_cgroup(pc); | |
2862 | if (PageCgroupUsed(pc)) { | |
2863 | memcg = pc->mem_cgroup; | |
2864 | ClearPageCgroupUsed(pc); | |
2865 | } | |
2866 | unlock_page_cgroup(pc); | |
2867 | ||
2868 | /* | |
2869 | * We trust that only if there is a memcg associated with the page, it | |
2870 | * is a valid allocation | |
2871 | */ | |
2872 | if (!memcg) | |
2873 | return; | |
2874 | ||
2875 | VM_BUG_ON(mem_cgroup_is_root(memcg)); | |
2876 | memcg_uncharge_kmem(memcg, PAGE_SIZE << order); | |
7ae1e1d0 GC |
2877 | } |
2878 | #endif /* CONFIG_MEMCG_KMEM */ | |
2879 | ||
ca3e0214 KH |
2880 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
2881 | ||
a0db00fc | 2882 | #define PCGF_NOCOPY_AT_SPLIT (1 << PCG_LOCK | 1 << PCG_MIGRATION) |
ca3e0214 KH |
2883 | /* |
2884 | * Because tail pages are not marked as "used", set it. We're under | |
e94c8a9c KH |
2885 | * zone->lru_lock, 'splitting on pmd' and compound_lock. |
2886 | * charge/uncharge will be never happen and move_account() is done under | |
2887 | * compound_lock(), so we don't have to take care of races. | |
ca3e0214 | 2888 | */ |
e94c8a9c | 2889 | void mem_cgroup_split_huge_fixup(struct page *head) |
ca3e0214 KH |
2890 | { |
2891 | struct page_cgroup *head_pc = lookup_page_cgroup(head); | |
e94c8a9c KH |
2892 | struct page_cgroup *pc; |
2893 | int i; | |
ca3e0214 | 2894 | |
3d37c4a9 KH |
2895 | if (mem_cgroup_disabled()) |
2896 | return; | |
e94c8a9c KH |
2897 | for (i = 1; i < HPAGE_PMD_NR; i++) { |
2898 | pc = head_pc + i; | |
2899 | pc->mem_cgroup = head_pc->mem_cgroup; | |
2900 | smp_wmb();/* see __commit_charge() */ | |
e94c8a9c KH |
2901 | pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT; |
2902 | } | |
ca3e0214 | 2903 | } |
12d27107 | 2904 | #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
ca3e0214 | 2905 | |
f817ed48 | 2906 | /** |
de3638d9 | 2907 | * mem_cgroup_move_account - move account of the page |
5564e88b | 2908 | * @page: the page |
7ec99d62 | 2909 | * @nr_pages: number of regular pages (>1 for huge pages) |
f817ed48 KH |
2910 | * @pc: page_cgroup of the page. |
2911 | * @from: mem_cgroup which the page is moved from. | |
2912 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
2913 | * | |
2914 | * The caller must confirm following. | |
08e552c6 | 2915 | * - page is not on LRU (isolate_page() is useful.) |
7ec99d62 | 2916 | * - compound_lock is held when nr_pages > 1 |
f817ed48 | 2917 | * |
2f3479b1 KH |
2918 | * This function doesn't do "charge" to new cgroup and doesn't do "uncharge" |
2919 | * from old cgroup. | |
f817ed48 | 2920 | */ |
7ec99d62 JW |
2921 | static int mem_cgroup_move_account(struct page *page, |
2922 | unsigned int nr_pages, | |
2923 | struct page_cgroup *pc, | |
2924 | struct mem_cgroup *from, | |
2f3479b1 | 2925 | struct mem_cgroup *to) |
f817ed48 | 2926 | { |
de3638d9 JW |
2927 | unsigned long flags; |
2928 | int ret; | |
b2402857 | 2929 | bool anon = PageAnon(page); |
987eba66 | 2930 | |
f817ed48 | 2931 | VM_BUG_ON(from == to); |
5564e88b | 2932 | VM_BUG_ON(PageLRU(page)); |
de3638d9 JW |
2933 | /* |
2934 | * The page is isolated from LRU. So, collapse function | |
2935 | * will not handle this page. But page splitting can happen. | |
2936 | * Do this check under compound_page_lock(). The caller should | |
2937 | * hold it. | |
2938 | */ | |
2939 | ret = -EBUSY; | |
7ec99d62 | 2940 | if (nr_pages > 1 && !PageTransHuge(page)) |
de3638d9 JW |
2941 | goto out; |
2942 | ||
2943 | lock_page_cgroup(pc); | |
2944 | ||
2945 | ret = -EINVAL; | |
2946 | if (!PageCgroupUsed(pc) || pc->mem_cgroup != from) | |
2947 | goto unlock; | |
2948 | ||
312734c0 | 2949 | move_lock_mem_cgroup(from, &flags); |
f817ed48 | 2950 | |
2ff76f11 | 2951 | if (!anon && page_mapped(page)) { |
c62b1a3b KH |
2952 | /* Update mapped_file data for mem_cgroup */ |
2953 | preempt_disable(); | |
2954 | __this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2955 | __this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2956 | preempt_enable(); | |
d69b042f | 2957 | } |
b2402857 | 2958 | mem_cgroup_charge_statistics(from, anon, -nr_pages); |
d69b042f | 2959 | |
854ffa8d | 2960 | /* caller should have done css_get */ |
08e552c6 | 2961 | pc->mem_cgroup = to; |
b2402857 | 2962 | mem_cgroup_charge_statistics(to, anon, nr_pages); |
312734c0 | 2963 | move_unlock_mem_cgroup(from, &flags); |
de3638d9 JW |
2964 | ret = 0; |
2965 | unlock: | |
57f9fd7d | 2966 | unlock_page_cgroup(pc); |
d2265e6f KH |
2967 | /* |
2968 | * check events | |
2969 | */ | |
5564e88b JW |
2970 | memcg_check_events(to, page); |
2971 | memcg_check_events(from, page); | |
de3638d9 | 2972 | out: |
f817ed48 KH |
2973 | return ret; |
2974 | } | |
2975 | ||
2ef37d3f MH |
2976 | /** |
2977 | * mem_cgroup_move_parent - moves page to the parent group | |
2978 | * @page: the page to move | |
2979 | * @pc: page_cgroup of the page | |
2980 | * @child: page's cgroup | |
2981 | * | |
2982 | * move charges to its parent or the root cgroup if the group has no | |
2983 | * parent (aka use_hierarchy==0). | |
2984 | * Although this might fail (get_page_unless_zero, isolate_lru_page or | |
2985 | * mem_cgroup_move_account fails) the failure is always temporary and | |
2986 | * it signals a race with a page removal/uncharge or migration. In the | |
2987 | * first case the page is on the way out and it will vanish from the LRU | |
2988 | * on the next attempt and the call should be retried later. | |
2989 | * Isolation from the LRU fails only if page has been isolated from | |
2990 | * the LRU since we looked at it and that usually means either global | |
2991 | * reclaim or migration going on. The page will either get back to the | |
2992 | * LRU or vanish. | |
2993 | * Finaly mem_cgroup_move_account fails only if the page got uncharged | |
2994 | * (!PageCgroupUsed) or moved to a different group. The page will | |
2995 | * disappear in the next attempt. | |
f817ed48 | 2996 | */ |
5564e88b JW |
2997 | static int mem_cgroup_move_parent(struct page *page, |
2998 | struct page_cgroup *pc, | |
6068bf01 | 2999 | struct mem_cgroup *child) |
f817ed48 | 3000 | { |
f817ed48 | 3001 | struct mem_cgroup *parent; |
7ec99d62 | 3002 | unsigned int nr_pages; |
4be4489f | 3003 | unsigned long uninitialized_var(flags); |
f817ed48 KH |
3004 | int ret; |
3005 | ||
d8423011 | 3006 | VM_BUG_ON(mem_cgroup_is_root(child)); |
f817ed48 | 3007 | |
57f9fd7d DN |
3008 | ret = -EBUSY; |
3009 | if (!get_page_unless_zero(page)) | |
3010 | goto out; | |
3011 | if (isolate_lru_page(page)) | |
3012 | goto put; | |
52dbb905 | 3013 | |
7ec99d62 | 3014 | nr_pages = hpage_nr_pages(page); |
08e552c6 | 3015 | |
cc926f78 KH |
3016 | parent = parent_mem_cgroup(child); |
3017 | /* | |
3018 | * If no parent, move charges to root cgroup. | |
3019 | */ | |
3020 | if (!parent) | |
3021 | parent = root_mem_cgroup; | |
f817ed48 | 3022 | |
2ef37d3f MH |
3023 | if (nr_pages > 1) { |
3024 | VM_BUG_ON(!PageTransHuge(page)); | |
987eba66 | 3025 | flags = compound_lock_irqsave(page); |
2ef37d3f | 3026 | } |
987eba66 | 3027 | |
cc926f78 | 3028 | ret = mem_cgroup_move_account(page, nr_pages, |
2f3479b1 | 3029 | pc, child, parent); |
cc926f78 KH |
3030 | if (!ret) |
3031 | __mem_cgroup_cancel_local_charge(child, nr_pages); | |
8dba474f | 3032 | |
7ec99d62 | 3033 | if (nr_pages > 1) |
987eba66 | 3034 | compound_unlock_irqrestore(page, flags); |
08e552c6 | 3035 | putback_lru_page(page); |
57f9fd7d | 3036 | put: |
40d58138 | 3037 | put_page(page); |
57f9fd7d | 3038 | out: |
f817ed48 KH |
3039 | return ret; |
3040 | } | |
3041 | ||
7a81b88c KH |
3042 | /* |
3043 | * Charge the memory controller for page usage. | |
3044 | * Return | |
3045 | * 0 if the charge was successful | |
3046 | * < 0 if the cgroup is over its limit | |
3047 | */ | |
3048 | static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, | |
73045c47 | 3049 | gfp_t gfp_mask, enum charge_type ctype) |
7a81b88c | 3050 | { |
c0ff4b85 | 3051 | struct mem_cgroup *memcg = NULL; |
7ec99d62 | 3052 | unsigned int nr_pages = 1; |
8493ae43 | 3053 | bool oom = true; |
7a81b88c | 3054 | int ret; |
ec168510 | 3055 | |
37c2ac78 | 3056 | if (PageTransHuge(page)) { |
7ec99d62 | 3057 | nr_pages <<= compound_order(page); |
37c2ac78 | 3058 | VM_BUG_ON(!PageTransHuge(page)); |
8493ae43 JW |
3059 | /* |
3060 | * Never OOM-kill a process for a huge page. The | |
3061 | * fault handler will fall back to regular pages. | |
3062 | */ | |
3063 | oom = false; | |
37c2ac78 | 3064 | } |
7a81b88c | 3065 | |
c0ff4b85 | 3066 | ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &memcg, oom); |
38c5d72f | 3067 | if (ret == -ENOMEM) |
7a81b88c | 3068 | return ret; |
ce587e65 | 3069 | __mem_cgroup_commit_charge(memcg, page, nr_pages, ctype, false); |
8a9f3ccd | 3070 | return 0; |
8a9f3ccd BS |
3071 | } |
3072 | ||
7a81b88c KH |
3073 | int mem_cgroup_newpage_charge(struct page *page, |
3074 | struct mm_struct *mm, gfp_t gfp_mask) | |
217bc319 | 3075 | { |
f8d66542 | 3076 | if (mem_cgroup_disabled()) |
cede86ac | 3077 | return 0; |
7a0524cf JW |
3078 | VM_BUG_ON(page_mapped(page)); |
3079 | VM_BUG_ON(page->mapping && !PageAnon(page)); | |
3080 | VM_BUG_ON(!mm); | |
217bc319 | 3081 | return mem_cgroup_charge_common(page, mm, gfp_mask, |
41326c17 | 3082 | MEM_CGROUP_CHARGE_TYPE_ANON); |
217bc319 KH |
3083 | } |
3084 | ||
54595fe2 KH |
3085 | /* |
3086 | * While swap-in, try_charge -> commit or cancel, the page is locked. | |
3087 | * And when try_charge() successfully returns, one refcnt to memcg without | |
21ae2956 | 3088 | * struct page_cgroup is acquired. This refcnt will be consumed by |
54595fe2 KH |
3089 | * "commit()" or removed by "cancel()" |
3090 | */ | |
0435a2fd JW |
3091 | static int __mem_cgroup_try_charge_swapin(struct mm_struct *mm, |
3092 | struct page *page, | |
3093 | gfp_t mask, | |
3094 | struct mem_cgroup **memcgp) | |
8c7c6e34 | 3095 | { |
c0ff4b85 | 3096 | struct mem_cgroup *memcg; |
90deb788 | 3097 | struct page_cgroup *pc; |
54595fe2 | 3098 | int ret; |
8c7c6e34 | 3099 | |
90deb788 JW |
3100 | pc = lookup_page_cgroup(page); |
3101 | /* | |
3102 | * Every swap fault against a single page tries to charge the | |
3103 | * page, bail as early as possible. shmem_unuse() encounters | |
3104 | * already charged pages, too. The USED bit is protected by | |
3105 | * the page lock, which serializes swap cache removal, which | |
3106 | * in turn serializes uncharging. | |
3107 | */ | |
3108 | if (PageCgroupUsed(pc)) | |
3109 | return 0; | |
8c7c6e34 KH |
3110 | if (!do_swap_account) |
3111 | goto charge_cur_mm; | |
c0ff4b85 R |
3112 | memcg = try_get_mem_cgroup_from_page(page); |
3113 | if (!memcg) | |
54595fe2 | 3114 | goto charge_cur_mm; |
72835c86 JW |
3115 | *memcgp = memcg; |
3116 | ret = __mem_cgroup_try_charge(NULL, mask, 1, memcgp, true); | |
c0ff4b85 | 3117 | css_put(&memcg->css); |
38c5d72f KH |
3118 | if (ret == -EINTR) |
3119 | ret = 0; | |
54595fe2 | 3120 | return ret; |
8c7c6e34 | 3121 | charge_cur_mm: |
38c5d72f KH |
3122 | ret = __mem_cgroup_try_charge(mm, mask, 1, memcgp, true); |
3123 | if (ret == -EINTR) | |
3124 | ret = 0; | |
3125 | return ret; | |
8c7c6e34 KH |
3126 | } |
3127 | ||
0435a2fd JW |
3128 | int mem_cgroup_try_charge_swapin(struct mm_struct *mm, struct page *page, |
3129 | gfp_t gfp_mask, struct mem_cgroup **memcgp) | |
3130 | { | |
3131 | *memcgp = NULL; | |
3132 | if (mem_cgroup_disabled()) | |
3133 | return 0; | |
bdf4f4d2 JW |
3134 | /* |
3135 | * A racing thread's fault, or swapoff, may have already | |
3136 | * updated the pte, and even removed page from swap cache: in | |
3137 | * those cases unuse_pte()'s pte_same() test will fail; but | |
3138 | * there's also a KSM case which does need to charge the page. | |
3139 | */ | |
3140 | if (!PageSwapCache(page)) { | |
3141 | int ret; | |
3142 | ||
3143 | ret = __mem_cgroup_try_charge(mm, gfp_mask, 1, memcgp, true); | |
3144 | if (ret == -EINTR) | |
3145 | ret = 0; | |
3146 | return ret; | |
3147 | } | |
0435a2fd JW |
3148 | return __mem_cgroup_try_charge_swapin(mm, page, gfp_mask, memcgp); |
3149 | } | |
3150 | ||
827a03d2 JW |
3151 | void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg) |
3152 | { | |
3153 | if (mem_cgroup_disabled()) | |
3154 | return; | |
3155 | if (!memcg) | |
3156 | return; | |
3157 | __mem_cgroup_cancel_charge(memcg, 1); | |
3158 | } | |
3159 | ||
83aae4c7 | 3160 | static void |
72835c86 | 3161 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg, |
83aae4c7 | 3162 | enum charge_type ctype) |
7a81b88c | 3163 | { |
f8d66542 | 3164 | if (mem_cgroup_disabled()) |
7a81b88c | 3165 | return; |
72835c86 | 3166 | if (!memcg) |
7a81b88c | 3167 | return; |
5a6475a4 | 3168 | |
ce587e65 | 3169 | __mem_cgroup_commit_charge(memcg, page, 1, ctype, true); |
8c7c6e34 KH |
3170 | /* |
3171 | * Now swap is on-memory. This means this page may be | |
3172 | * counted both as mem and swap....double count. | |
03f3c433 KH |
3173 | * Fix it by uncharging from memsw. Basically, this SwapCache is stable |
3174 | * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page() | |
3175 | * may call delete_from_swap_cache() before reach here. | |
8c7c6e34 | 3176 | */ |
03f3c433 | 3177 | if (do_swap_account && PageSwapCache(page)) { |
8c7c6e34 | 3178 | swp_entry_t ent = {.val = page_private(page)}; |
86493009 | 3179 | mem_cgroup_uncharge_swap(ent); |
8c7c6e34 | 3180 | } |
7a81b88c KH |
3181 | } |
3182 | ||
72835c86 JW |
3183 | void mem_cgroup_commit_charge_swapin(struct page *page, |
3184 | struct mem_cgroup *memcg) | |
83aae4c7 | 3185 | { |
72835c86 | 3186 | __mem_cgroup_commit_charge_swapin(page, memcg, |
41326c17 | 3187 | MEM_CGROUP_CHARGE_TYPE_ANON); |
83aae4c7 DN |
3188 | } |
3189 | ||
827a03d2 JW |
3190 | int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, |
3191 | gfp_t gfp_mask) | |
7a81b88c | 3192 | { |
827a03d2 JW |
3193 | struct mem_cgroup *memcg = NULL; |
3194 | enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE; | |
3195 | int ret; | |
3196 | ||
f8d66542 | 3197 | if (mem_cgroup_disabled()) |
827a03d2 JW |
3198 | return 0; |
3199 | if (PageCompound(page)) | |
3200 | return 0; | |
3201 | ||
827a03d2 JW |
3202 | if (!PageSwapCache(page)) |
3203 | ret = mem_cgroup_charge_common(page, mm, gfp_mask, type); | |
3204 | else { /* page is swapcache/shmem */ | |
0435a2fd JW |
3205 | ret = __mem_cgroup_try_charge_swapin(mm, page, |
3206 | gfp_mask, &memcg); | |
827a03d2 JW |
3207 | if (!ret) |
3208 | __mem_cgroup_commit_charge_swapin(page, memcg, type); | |
3209 | } | |
3210 | return ret; | |
7a81b88c KH |
3211 | } |
3212 | ||
c0ff4b85 | 3213 | static void mem_cgroup_do_uncharge(struct mem_cgroup *memcg, |
7ec99d62 JW |
3214 | unsigned int nr_pages, |
3215 | const enum charge_type ctype) | |
569b846d KH |
3216 | { |
3217 | struct memcg_batch_info *batch = NULL; | |
3218 | bool uncharge_memsw = true; | |
7ec99d62 | 3219 | |
569b846d KH |
3220 | /* If swapout, usage of swap doesn't decrease */ |
3221 | if (!do_swap_account || ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) | |
3222 | uncharge_memsw = false; | |
569b846d KH |
3223 | |
3224 | batch = ¤t->memcg_batch; | |
3225 | /* | |
3226 | * In usual, we do css_get() when we remember memcg pointer. | |
3227 | * But in this case, we keep res->usage until end of a series of | |
3228 | * uncharges. Then, it's ok to ignore memcg's refcnt. | |
3229 | */ | |
3230 | if (!batch->memcg) | |
c0ff4b85 | 3231 | batch->memcg = memcg; |
3c11ecf4 KH |
3232 | /* |
3233 | * do_batch > 0 when unmapping pages or inode invalidate/truncate. | |
25985edc | 3234 | * In those cases, all pages freed continuously can be expected to be in |
3c11ecf4 KH |
3235 | * the same cgroup and we have chance to coalesce uncharges. |
3236 | * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE) | |
3237 | * because we want to do uncharge as soon as possible. | |
3238 | */ | |
3239 | ||
3240 | if (!batch->do_batch || test_thread_flag(TIF_MEMDIE)) | |
3241 | goto direct_uncharge; | |
3242 | ||
7ec99d62 | 3243 | if (nr_pages > 1) |
ec168510 AA |
3244 | goto direct_uncharge; |
3245 | ||
569b846d KH |
3246 | /* |
3247 | * In typical case, batch->memcg == mem. This means we can | |
3248 | * merge a series of uncharges to an uncharge of res_counter. | |
3249 | * If not, we uncharge res_counter ony by one. | |
3250 | */ | |
c0ff4b85 | 3251 | if (batch->memcg != memcg) |
569b846d KH |
3252 | goto direct_uncharge; |
3253 | /* remember freed charge and uncharge it later */ | |
7ffd4ca7 | 3254 | batch->nr_pages++; |
569b846d | 3255 | if (uncharge_memsw) |
7ffd4ca7 | 3256 | batch->memsw_nr_pages++; |
569b846d KH |
3257 | return; |
3258 | direct_uncharge: | |
c0ff4b85 | 3259 | res_counter_uncharge(&memcg->res, nr_pages * PAGE_SIZE); |
569b846d | 3260 | if (uncharge_memsw) |
c0ff4b85 R |
3261 | res_counter_uncharge(&memcg->memsw, nr_pages * PAGE_SIZE); |
3262 | if (unlikely(batch->memcg != memcg)) | |
3263 | memcg_oom_recover(memcg); | |
569b846d | 3264 | } |
7a81b88c | 3265 | |
8a9f3ccd | 3266 | /* |
69029cd5 | 3267 | * uncharge if !page_mapped(page) |
8a9f3ccd | 3268 | */ |
8c7c6e34 | 3269 | static struct mem_cgroup * |
0030f535 JW |
3270 | __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype, |
3271 | bool end_migration) | |
8a9f3ccd | 3272 | { |
c0ff4b85 | 3273 | struct mem_cgroup *memcg = NULL; |
7ec99d62 JW |
3274 | unsigned int nr_pages = 1; |
3275 | struct page_cgroup *pc; | |
b2402857 | 3276 | bool anon; |
8a9f3ccd | 3277 | |
f8d66542 | 3278 | if (mem_cgroup_disabled()) |
8c7c6e34 | 3279 | return NULL; |
4077960e | 3280 | |
0c59b89c | 3281 | VM_BUG_ON(PageSwapCache(page)); |
d13d1443 | 3282 | |
37c2ac78 | 3283 | if (PageTransHuge(page)) { |
7ec99d62 | 3284 | nr_pages <<= compound_order(page); |
37c2ac78 AA |
3285 | VM_BUG_ON(!PageTransHuge(page)); |
3286 | } | |
8697d331 | 3287 | /* |
3c541e14 | 3288 | * Check if our page_cgroup is valid |
8697d331 | 3289 | */ |
52d4b9ac | 3290 | pc = lookup_page_cgroup(page); |
cfa44946 | 3291 | if (unlikely(!PageCgroupUsed(pc))) |
8c7c6e34 | 3292 | return NULL; |
b9c565d5 | 3293 | |
52d4b9ac | 3294 | lock_page_cgroup(pc); |
d13d1443 | 3295 | |
c0ff4b85 | 3296 | memcg = pc->mem_cgroup; |
8c7c6e34 | 3297 | |
d13d1443 KH |
3298 | if (!PageCgroupUsed(pc)) |
3299 | goto unlock_out; | |
3300 | ||
b2402857 KH |
3301 | anon = PageAnon(page); |
3302 | ||
d13d1443 | 3303 | switch (ctype) { |
41326c17 | 3304 | case MEM_CGROUP_CHARGE_TYPE_ANON: |
2ff76f11 KH |
3305 | /* |
3306 | * Generally PageAnon tells if it's the anon statistics to be | |
3307 | * updated; but sometimes e.g. mem_cgroup_uncharge_page() is | |
3308 | * used before page reached the stage of being marked PageAnon. | |
3309 | */ | |
b2402857 KH |
3310 | anon = true; |
3311 | /* fallthrough */ | |
8a9478ca | 3312 | case MEM_CGROUP_CHARGE_TYPE_DROP: |
ac39cf8c | 3313 | /* See mem_cgroup_prepare_migration() */ |
0030f535 JW |
3314 | if (page_mapped(page)) |
3315 | goto unlock_out; | |
3316 | /* | |
3317 | * Pages under migration may not be uncharged. But | |
3318 | * end_migration() /must/ be the one uncharging the | |
3319 | * unused post-migration page and so it has to call | |
3320 | * here with the migration bit still set. See the | |
3321 | * res_counter handling below. | |
3322 | */ | |
3323 | if (!end_migration && PageCgroupMigration(pc)) | |
d13d1443 KH |
3324 | goto unlock_out; |
3325 | break; | |
3326 | case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: | |
3327 | if (!PageAnon(page)) { /* Shared memory */ | |
3328 | if (page->mapping && !page_is_file_cache(page)) | |
3329 | goto unlock_out; | |
3330 | } else if (page_mapped(page)) /* Anon */ | |
3331 | goto unlock_out; | |
3332 | break; | |
3333 | default: | |
3334 | break; | |
52d4b9ac | 3335 | } |
d13d1443 | 3336 | |
b2402857 | 3337 | mem_cgroup_charge_statistics(memcg, anon, -nr_pages); |
04046e1a | 3338 | |
52d4b9ac | 3339 | ClearPageCgroupUsed(pc); |
544122e5 KH |
3340 | /* |
3341 | * pc->mem_cgroup is not cleared here. It will be accessed when it's | |
3342 | * freed from LRU. This is safe because uncharged page is expected not | |
3343 | * to be reused (freed soon). Exception is SwapCache, it's handled by | |
3344 | * special functions. | |
3345 | */ | |
b9c565d5 | 3346 | |
52d4b9ac | 3347 | unlock_page_cgroup(pc); |
f75ca962 | 3348 | /* |
c0ff4b85 | 3349 | * even after unlock, we have memcg->res.usage here and this memcg |
f75ca962 KH |
3350 | * will never be freed. |
3351 | */ | |
c0ff4b85 | 3352 | memcg_check_events(memcg, page); |
f75ca962 | 3353 | if (do_swap_account && ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) { |
c0ff4b85 R |
3354 | mem_cgroup_swap_statistics(memcg, true); |
3355 | mem_cgroup_get(memcg); | |
f75ca962 | 3356 | } |
0030f535 JW |
3357 | /* |
3358 | * Migration does not charge the res_counter for the | |
3359 | * replacement page, so leave it alone when phasing out the | |
3360 | * page that is unused after the migration. | |
3361 | */ | |
3362 | if (!end_migration && !mem_cgroup_is_root(memcg)) | |
c0ff4b85 | 3363 | mem_cgroup_do_uncharge(memcg, nr_pages, ctype); |
6d12e2d8 | 3364 | |
c0ff4b85 | 3365 | return memcg; |
d13d1443 KH |
3366 | |
3367 | unlock_out: | |
3368 | unlock_page_cgroup(pc); | |
8c7c6e34 | 3369 | return NULL; |
3c541e14 BS |
3370 | } |
3371 | ||
69029cd5 KH |
3372 | void mem_cgroup_uncharge_page(struct page *page) |
3373 | { | |
52d4b9ac KH |
3374 | /* early check. */ |
3375 | if (page_mapped(page)) | |
3376 | return; | |
40f23a21 | 3377 | VM_BUG_ON(page->mapping && !PageAnon(page)); |
0c59b89c JW |
3378 | if (PageSwapCache(page)) |
3379 | return; | |
0030f535 | 3380 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_ANON, false); |
69029cd5 KH |
3381 | } |
3382 | ||
3383 | void mem_cgroup_uncharge_cache_page(struct page *page) | |
3384 | { | |
3385 | VM_BUG_ON(page_mapped(page)); | |
b7abea96 | 3386 | VM_BUG_ON(page->mapping); |
0030f535 | 3387 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE, false); |
69029cd5 KH |
3388 | } |
3389 | ||
569b846d KH |
3390 | /* |
3391 | * Batch_start/batch_end is called in unmap_page_range/invlidate/trucate. | |
3392 | * In that cases, pages are freed continuously and we can expect pages | |
3393 | * are in the same memcg. All these calls itself limits the number of | |
3394 | * pages freed at once, then uncharge_start/end() is called properly. | |
3395 | * This may be called prural(2) times in a context, | |
3396 | */ | |
3397 | ||
3398 | void mem_cgroup_uncharge_start(void) | |
3399 | { | |
3400 | current->memcg_batch.do_batch++; | |
3401 | /* We can do nest. */ | |
3402 | if (current->memcg_batch.do_batch == 1) { | |
3403 | current->memcg_batch.memcg = NULL; | |
7ffd4ca7 JW |
3404 | current->memcg_batch.nr_pages = 0; |
3405 | current->memcg_batch.memsw_nr_pages = 0; | |
569b846d KH |
3406 | } |
3407 | } | |
3408 | ||
3409 | void mem_cgroup_uncharge_end(void) | |
3410 | { | |
3411 | struct memcg_batch_info *batch = ¤t->memcg_batch; | |
3412 | ||
3413 | if (!batch->do_batch) | |
3414 | return; | |
3415 | ||
3416 | batch->do_batch--; | |
3417 | if (batch->do_batch) /* If stacked, do nothing. */ | |
3418 | return; | |
3419 | ||
3420 | if (!batch->memcg) | |
3421 | return; | |
3422 | /* | |
3423 | * This "batch->memcg" is valid without any css_get/put etc... | |
3424 | * bacause we hide charges behind us. | |
3425 | */ | |
7ffd4ca7 JW |
3426 | if (batch->nr_pages) |
3427 | res_counter_uncharge(&batch->memcg->res, | |
3428 | batch->nr_pages * PAGE_SIZE); | |
3429 | if (batch->memsw_nr_pages) | |
3430 | res_counter_uncharge(&batch->memcg->memsw, | |
3431 | batch->memsw_nr_pages * PAGE_SIZE); | |
3c11ecf4 | 3432 | memcg_oom_recover(batch->memcg); |
569b846d KH |
3433 | /* forget this pointer (for sanity check) */ |
3434 | batch->memcg = NULL; | |
3435 | } | |
3436 | ||
e767e056 | 3437 | #ifdef CONFIG_SWAP |
8c7c6e34 | 3438 | /* |
e767e056 | 3439 | * called after __delete_from_swap_cache() and drop "page" account. |
8c7c6e34 KH |
3440 | * memcg information is recorded to swap_cgroup of "ent" |
3441 | */ | |
8a9478ca KH |
3442 | void |
3443 | mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout) | |
8c7c6e34 KH |
3444 | { |
3445 | struct mem_cgroup *memcg; | |
8a9478ca KH |
3446 | int ctype = MEM_CGROUP_CHARGE_TYPE_SWAPOUT; |
3447 | ||
3448 | if (!swapout) /* this was a swap cache but the swap is unused ! */ | |
3449 | ctype = MEM_CGROUP_CHARGE_TYPE_DROP; | |
3450 | ||
0030f535 | 3451 | memcg = __mem_cgroup_uncharge_common(page, ctype, false); |
8c7c6e34 | 3452 | |
f75ca962 KH |
3453 | /* |
3454 | * record memcg information, if swapout && memcg != NULL, | |
3455 | * mem_cgroup_get() was called in uncharge(). | |
3456 | */ | |
3457 | if (do_swap_account && swapout && memcg) | |
a3b2d692 | 3458 | swap_cgroup_record(ent, css_id(&memcg->css)); |
8c7c6e34 | 3459 | } |
e767e056 | 3460 | #endif |
8c7c6e34 | 3461 | |
c255a458 | 3462 | #ifdef CONFIG_MEMCG_SWAP |
8c7c6e34 KH |
3463 | /* |
3464 | * called from swap_entry_free(). remove record in swap_cgroup and | |
3465 | * uncharge "memsw" account. | |
3466 | */ | |
3467 | void mem_cgroup_uncharge_swap(swp_entry_t ent) | |
d13d1443 | 3468 | { |
8c7c6e34 | 3469 | struct mem_cgroup *memcg; |
a3b2d692 | 3470 | unsigned short id; |
8c7c6e34 KH |
3471 | |
3472 | if (!do_swap_account) | |
3473 | return; | |
3474 | ||
a3b2d692 KH |
3475 | id = swap_cgroup_record(ent, 0); |
3476 | rcu_read_lock(); | |
3477 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 3478 | if (memcg) { |
a3b2d692 KH |
3479 | /* |
3480 | * We uncharge this because swap is freed. | |
3481 | * This memcg can be obsolete one. We avoid calling css_tryget | |
3482 | */ | |
0c3e73e8 | 3483 | if (!mem_cgroup_is_root(memcg)) |
4e649152 | 3484 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
0c3e73e8 | 3485 | mem_cgroup_swap_statistics(memcg, false); |
8c7c6e34 KH |
3486 | mem_cgroup_put(memcg); |
3487 | } | |
a3b2d692 | 3488 | rcu_read_unlock(); |
d13d1443 | 3489 | } |
02491447 DN |
3490 | |
3491 | /** | |
3492 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
3493 | * @entry: swap entry to be moved | |
3494 | * @from: mem_cgroup which the entry is moved from | |
3495 | * @to: mem_cgroup which the entry is moved to | |
3496 | * | |
3497 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
3498 | * as the mem_cgroup's id of @from. | |
3499 | * | |
3500 | * Returns 0 on success, -EINVAL on failure. | |
3501 | * | |
3502 | * The caller must have charged to @to, IOW, called res_counter_charge() about | |
3503 | * both res and memsw, and called css_get(). | |
3504 | */ | |
3505 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 3506 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
3507 | { |
3508 | unsigned short old_id, new_id; | |
3509 | ||
3510 | old_id = css_id(&from->css); | |
3511 | new_id = css_id(&to->css); | |
3512 | ||
3513 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
02491447 | 3514 | mem_cgroup_swap_statistics(from, false); |
483c30b5 | 3515 | mem_cgroup_swap_statistics(to, true); |
02491447 | 3516 | /* |
483c30b5 DN |
3517 | * This function is only called from task migration context now. |
3518 | * It postpones res_counter and refcount handling till the end | |
3519 | * of task migration(mem_cgroup_clear_mc()) for performance | |
3520 | * improvement. But we cannot postpone mem_cgroup_get(to) | |
3521 | * because if the process that has been moved to @to does | |
3522 | * swap-in, the refcount of @to might be decreased to 0. | |
02491447 | 3523 | */ |
02491447 | 3524 | mem_cgroup_get(to); |
02491447 DN |
3525 | return 0; |
3526 | } | |
3527 | return -EINVAL; | |
3528 | } | |
3529 | #else | |
3530 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
e91cbb42 | 3531 | struct mem_cgroup *from, struct mem_cgroup *to) |
02491447 DN |
3532 | { |
3533 | return -EINVAL; | |
3534 | } | |
8c7c6e34 | 3535 | #endif |
d13d1443 | 3536 | |
ae41be37 | 3537 | /* |
01b1ae63 KH |
3538 | * Before starting migration, account PAGE_SIZE to mem_cgroup that the old |
3539 | * page belongs to. | |
ae41be37 | 3540 | */ |
0030f535 JW |
3541 | void mem_cgroup_prepare_migration(struct page *page, struct page *newpage, |
3542 | struct mem_cgroup **memcgp) | |
ae41be37 | 3543 | { |
c0ff4b85 | 3544 | struct mem_cgroup *memcg = NULL; |
b32967ff | 3545 | unsigned int nr_pages = 1; |
7ec99d62 | 3546 | struct page_cgroup *pc; |
ac39cf8c | 3547 | enum charge_type ctype; |
8869b8f6 | 3548 | |
72835c86 | 3549 | *memcgp = NULL; |
56039efa | 3550 | |
f8d66542 | 3551 | if (mem_cgroup_disabled()) |
0030f535 | 3552 | return; |
4077960e | 3553 | |
b32967ff MG |
3554 | if (PageTransHuge(page)) |
3555 | nr_pages <<= compound_order(page); | |
3556 | ||
52d4b9ac KH |
3557 | pc = lookup_page_cgroup(page); |
3558 | lock_page_cgroup(pc); | |
3559 | if (PageCgroupUsed(pc)) { | |
c0ff4b85 R |
3560 | memcg = pc->mem_cgroup; |
3561 | css_get(&memcg->css); | |
ac39cf8c AM |
3562 | /* |
3563 | * At migrating an anonymous page, its mapcount goes down | |
3564 | * to 0 and uncharge() will be called. But, even if it's fully | |
3565 | * unmapped, migration may fail and this page has to be | |
3566 | * charged again. We set MIGRATION flag here and delay uncharge | |
3567 | * until end_migration() is called | |
3568 | * | |
3569 | * Corner Case Thinking | |
3570 | * A) | |
3571 | * When the old page was mapped as Anon and it's unmap-and-freed | |
3572 | * while migration was ongoing. | |
3573 | * If unmap finds the old page, uncharge() of it will be delayed | |
3574 | * until end_migration(). If unmap finds a new page, it's | |
3575 | * uncharged when it make mapcount to be 1->0. If unmap code | |
3576 | * finds swap_migration_entry, the new page will not be mapped | |
3577 | * and end_migration() will find it(mapcount==0). | |
3578 | * | |
3579 | * B) | |
3580 | * When the old page was mapped but migraion fails, the kernel | |
3581 | * remaps it. A charge for it is kept by MIGRATION flag even | |
3582 | * if mapcount goes down to 0. We can do remap successfully | |
3583 | * without charging it again. | |
3584 | * | |
3585 | * C) | |
3586 | * The "old" page is under lock_page() until the end of | |
3587 | * migration, so, the old page itself will not be swapped-out. | |
3588 | * If the new page is swapped out before end_migraton, our | |
3589 | * hook to usual swap-out path will catch the event. | |
3590 | */ | |
3591 | if (PageAnon(page)) | |
3592 | SetPageCgroupMigration(pc); | |
e8589cc1 | 3593 | } |
52d4b9ac | 3594 | unlock_page_cgroup(pc); |
ac39cf8c AM |
3595 | /* |
3596 | * If the page is not charged at this point, | |
3597 | * we return here. | |
3598 | */ | |
c0ff4b85 | 3599 | if (!memcg) |
0030f535 | 3600 | return; |
01b1ae63 | 3601 | |
72835c86 | 3602 | *memcgp = memcg; |
ac39cf8c AM |
3603 | /* |
3604 | * We charge new page before it's used/mapped. So, even if unlock_page() | |
3605 | * is called before end_migration, we can catch all events on this new | |
3606 | * page. In the case new page is migrated but not remapped, new page's | |
3607 | * mapcount will be finally 0 and we call uncharge in end_migration(). | |
3608 | */ | |
ac39cf8c | 3609 | if (PageAnon(page)) |
41326c17 | 3610 | ctype = MEM_CGROUP_CHARGE_TYPE_ANON; |
ac39cf8c | 3611 | else |
62ba7442 | 3612 | ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; |
0030f535 JW |
3613 | /* |
3614 | * The page is committed to the memcg, but it's not actually | |
3615 | * charged to the res_counter since we plan on replacing the | |
3616 | * old one and only one page is going to be left afterwards. | |
3617 | */ | |
b32967ff | 3618 | __mem_cgroup_commit_charge(memcg, newpage, nr_pages, ctype, false); |
ae41be37 | 3619 | } |
8869b8f6 | 3620 | |
69029cd5 | 3621 | /* remove redundant charge if migration failed*/ |
c0ff4b85 | 3622 | void mem_cgroup_end_migration(struct mem_cgroup *memcg, |
50de1dd9 | 3623 | struct page *oldpage, struct page *newpage, bool migration_ok) |
ae41be37 | 3624 | { |
ac39cf8c | 3625 | struct page *used, *unused; |
01b1ae63 | 3626 | struct page_cgroup *pc; |
b2402857 | 3627 | bool anon; |
01b1ae63 | 3628 | |
c0ff4b85 | 3629 | if (!memcg) |
01b1ae63 | 3630 | return; |
b25ed609 | 3631 | |
50de1dd9 | 3632 | if (!migration_ok) { |
ac39cf8c AM |
3633 | used = oldpage; |
3634 | unused = newpage; | |
01b1ae63 | 3635 | } else { |
ac39cf8c | 3636 | used = newpage; |
01b1ae63 KH |
3637 | unused = oldpage; |
3638 | } | |
0030f535 | 3639 | anon = PageAnon(used); |
7d188958 JW |
3640 | __mem_cgroup_uncharge_common(unused, |
3641 | anon ? MEM_CGROUP_CHARGE_TYPE_ANON | |
3642 | : MEM_CGROUP_CHARGE_TYPE_CACHE, | |
3643 | true); | |
0030f535 | 3644 | css_put(&memcg->css); |
69029cd5 | 3645 | /* |
ac39cf8c AM |
3646 | * We disallowed uncharge of pages under migration because mapcount |
3647 | * of the page goes down to zero, temporarly. | |
3648 | * Clear the flag and check the page should be charged. | |
01b1ae63 | 3649 | */ |
ac39cf8c AM |
3650 | pc = lookup_page_cgroup(oldpage); |
3651 | lock_page_cgroup(pc); | |
3652 | ClearPageCgroupMigration(pc); | |
3653 | unlock_page_cgroup(pc); | |
ac39cf8c | 3654 | |
01b1ae63 | 3655 | /* |
ac39cf8c AM |
3656 | * If a page is a file cache, radix-tree replacement is very atomic |
3657 | * and we can skip this check. When it was an Anon page, its mapcount | |
3658 | * goes down to 0. But because we added MIGRATION flage, it's not | |
3659 | * uncharged yet. There are several case but page->mapcount check | |
3660 | * and USED bit check in mem_cgroup_uncharge_page() will do enough | |
3661 | * check. (see prepare_charge() also) | |
69029cd5 | 3662 | */ |
b2402857 | 3663 | if (anon) |
ac39cf8c | 3664 | mem_cgroup_uncharge_page(used); |
ae41be37 | 3665 | } |
78fb7466 | 3666 | |
ab936cbc KH |
3667 | /* |
3668 | * At replace page cache, newpage is not under any memcg but it's on | |
3669 | * LRU. So, this function doesn't touch res_counter but handles LRU | |
3670 | * in correct way. Both pages are locked so we cannot race with uncharge. | |
3671 | */ | |
3672 | void mem_cgroup_replace_page_cache(struct page *oldpage, | |
3673 | struct page *newpage) | |
3674 | { | |
bde05d1c | 3675 | struct mem_cgroup *memcg = NULL; |
ab936cbc | 3676 | struct page_cgroup *pc; |
ab936cbc | 3677 | enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE; |
ab936cbc KH |
3678 | |
3679 | if (mem_cgroup_disabled()) | |
3680 | return; | |
3681 | ||
3682 | pc = lookup_page_cgroup(oldpage); | |
3683 | /* fix accounting on old pages */ | |
3684 | lock_page_cgroup(pc); | |
bde05d1c HD |
3685 | if (PageCgroupUsed(pc)) { |
3686 | memcg = pc->mem_cgroup; | |
3687 | mem_cgroup_charge_statistics(memcg, false, -1); | |
3688 | ClearPageCgroupUsed(pc); | |
3689 | } | |
ab936cbc KH |
3690 | unlock_page_cgroup(pc); |
3691 | ||
bde05d1c HD |
3692 | /* |
3693 | * When called from shmem_replace_page(), in some cases the | |
3694 | * oldpage has already been charged, and in some cases not. | |
3695 | */ | |
3696 | if (!memcg) | |
3697 | return; | |
ab936cbc KH |
3698 | /* |
3699 | * Even if newpage->mapping was NULL before starting replacement, | |
3700 | * the newpage may be on LRU(or pagevec for LRU) already. We lock | |
3701 | * LRU while we overwrite pc->mem_cgroup. | |
3702 | */ | |
ce587e65 | 3703 | __mem_cgroup_commit_charge(memcg, newpage, 1, type, true); |
ab936cbc KH |
3704 | } |
3705 | ||
f212ad7c DN |
3706 | #ifdef CONFIG_DEBUG_VM |
3707 | static struct page_cgroup *lookup_page_cgroup_used(struct page *page) | |
3708 | { | |
3709 | struct page_cgroup *pc; | |
3710 | ||
3711 | pc = lookup_page_cgroup(page); | |
cfa44946 JW |
3712 | /* |
3713 | * Can be NULL while feeding pages into the page allocator for | |
3714 | * the first time, i.e. during boot or memory hotplug; | |
3715 | * or when mem_cgroup_disabled(). | |
3716 | */ | |
f212ad7c DN |
3717 | if (likely(pc) && PageCgroupUsed(pc)) |
3718 | return pc; | |
3719 | return NULL; | |
3720 | } | |
3721 | ||
3722 | bool mem_cgroup_bad_page_check(struct page *page) | |
3723 | { | |
3724 | if (mem_cgroup_disabled()) | |
3725 | return false; | |
3726 | ||
3727 | return lookup_page_cgroup_used(page) != NULL; | |
3728 | } | |
3729 | ||
3730 | void mem_cgroup_print_bad_page(struct page *page) | |
3731 | { | |
3732 | struct page_cgroup *pc; | |
3733 | ||
3734 | pc = lookup_page_cgroup_used(page); | |
3735 | if (pc) { | |
90b3feae | 3736 | printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p\n", |
f212ad7c | 3737 | pc, pc->flags, pc->mem_cgroup); |
f212ad7c DN |
3738 | } |
3739 | } | |
3740 | #endif | |
3741 | ||
8c7c6e34 KH |
3742 | static DEFINE_MUTEX(set_limit_mutex); |
3743 | ||
d38d2a75 | 3744 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
8c7c6e34 | 3745 | unsigned long long val) |
628f4235 | 3746 | { |
81d39c20 | 3747 | int retry_count; |
3c11ecf4 | 3748 | u64 memswlimit, memlimit; |
628f4235 | 3749 | int ret = 0; |
81d39c20 KH |
3750 | int children = mem_cgroup_count_children(memcg); |
3751 | u64 curusage, oldusage; | |
3c11ecf4 | 3752 | int enlarge; |
81d39c20 KH |
3753 | |
3754 | /* | |
3755 | * For keeping hierarchical_reclaim simple, how long we should retry | |
3756 | * is depends on callers. We set our retry-count to be function | |
3757 | * of # of children which we should visit in this loop. | |
3758 | */ | |
3759 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; | |
3760 | ||
3761 | oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); | |
628f4235 | 3762 | |
3c11ecf4 | 3763 | enlarge = 0; |
8c7c6e34 | 3764 | while (retry_count) { |
628f4235 KH |
3765 | if (signal_pending(current)) { |
3766 | ret = -EINTR; | |
3767 | break; | |
3768 | } | |
8c7c6e34 KH |
3769 | /* |
3770 | * Rather than hide all in some function, I do this in | |
3771 | * open coded manner. You see what this really does. | |
aaad153e | 3772 | * We have to guarantee memcg->res.limit <= memcg->memsw.limit. |
8c7c6e34 KH |
3773 | */ |
3774 | mutex_lock(&set_limit_mutex); | |
3775 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
3776 | if (memswlimit < val) { | |
3777 | ret = -EINVAL; | |
3778 | mutex_unlock(&set_limit_mutex); | |
628f4235 KH |
3779 | break; |
3780 | } | |
3c11ecf4 KH |
3781 | |
3782 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3783 | if (memlimit < val) | |
3784 | enlarge = 1; | |
3785 | ||
8c7c6e34 | 3786 | ret = res_counter_set_limit(&memcg->res, val); |
22a668d7 KH |
3787 | if (!ret) { |
3788 | if (memswlimit == val) | |
3789 | memcg->memsw_is_minimum = true; | |
3790 | else | |
3791 | memcg->memsw_is_minimum = false; | |
3792 | } | |
8c7c6e34 KH |
3793 | mutex_unlock(&set_limit_mutex); |
3794 | ||
3795 | if (!ret) | |
3796 | break; | |
3797 | ||
5660048c JW |
3798 | mem_cgroup_reclaim(memcg, GFP_KERNEL, |
3799 | MEM_CGROUP_RECLAIM_SHRINK); | |
81d39c20 KH |
3800 | curusage = res_counter_read_u64(&memcg->res, RES_USAGE); |
3801 | /* Usage is reduced ? */ | |
3802 | if (curusage >= oldusage) | |
3803 | retry_count--; | |
3804 | else | |
3805 | oldusage = curusage; | |
8c7c6e34 | 3806 | } |
3c11ecf4 KH |
3807 | if (!ret && enlarge) |
3808 | memcg_oom_recover(memcg); | |
14797e23 | 3809 | |
8c7c6e34 KH |
3810 | return ret; |
3811 | } | |
3812 | ||
338c8431 LZ |
3813 | static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, |
3814 | unsigned long long val) | |
8c7c6e34 | 3815 | { |
81d39c20 | 3816 | int retry_count; |
3c11ecf4 | 3817 | u64 memlimit, memswlimit, oldusage, curusage; |
81d39c20 KH |
3818 | int children = mem_cgroup_count_children(memcg); |
3819 | int ret = -EBUSY; | |
3c11ecf4 | 3820 | int enlarge = 0; |
8c7c6e34 | 3821 | |
81d39c20 KH |
3822 | /* see mem_cgroup_resize_res_limit */ |
3823 | retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; | |
3824 | oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); | |
8c7c6e34 KH |
3825 | while (retry_count) { |
3826 | if (signal_pending(current)) { | |
3827 | ret = -EINTR; | |
3828 | break; | |
3829 | } | |
3830 | /* | |
3831 | * Rather than hide all in some function, I do this in | |
3832 | * open coded manner. You see what this really does. | |
aaad153e | 3833 | * We have to guarantee memcg->res.limit <= memcg->memsw.limit. |
8c7c6e34 KH |
3834 | */ |
3835 | mutex_lock(&set_limit_mutex); | |
3836 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3837 | if (memlimit > val) { | |
3838 | ret = -EINVAL; | |
3839 | mutex_unlock(&set_limit_mutex); | |
3840 | break; | |
3841 | } | |
3c11ecf4 KH |
3842 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
3843 | if (memswlimit < val) | |
3844 | enlarge = 1; | |
8c7c6e34 | 3845 | ret = res_counter_set_limit(&memcg->memsw, val); |
22a668d7 KH |
3846 | if (!ret) { |
3847 | if (memlimit == val) | |
3848 | memcg->memsw_is_minimum = true; | |
3849 | else | |
3850 | memcg->memsw_is_minimum = false; | |
3851 | } | |
8c7c6e34 KH |
3852 | mutex_unlock(&set_limit_mutex); |
3853 | ||
3854 | if (!ret) | |
3855 | break; | |
3856 | ||
5660048c JW |
3857 | mem_cgroup_reclaim(memcg, GFP_KERNEL, |
3858 | MEM_CGROUP_RECLAIM_NOSWAP | | |
3859 | MEM_CGROUP_RECLAIM_SHRINK); | |
8c7c6e34 | 3860 | curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); |
81d39c20 | 3861 | /* Usage is reduced ? */ |
8c7c6e34 | 3862 | if (curusage >= oldusage) |
628f4235 | 3863 | retry_count--; |
81d39c20 KH |
3864 | else |
3865 | oldusage = curusage; | |
628f4235 | 3866 | } |
3c11ecf4 KH |
3867 | if (!ret && enlarge) |
3868 | memcg_oom_recover(memcg); | |
628f4235 KH |
3869 | return ret; |
3870 | } | |
3871 | ||
4e416953 | 3872 | unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, |
0ae5e89c YH |
3873 | gfp_t gfp_mask, |
3874 | unsigned long *total_scanned) | |
4e416953 BS |
3875 | { |
3876 | unsigned long nr_reclaimed = 0; | |
3877 | struct mem_cgroup_per_zone *mz, *next_mz = NULL; | |
3878 | unsigned long reclaimed; | |
3879 | int loop = 0; | |
3880 | struct mem_cgroup_tree_per_zone *mctz; | |
ef8745c1 | 3881 | unsigned long long excess; |
0ae5e89c | 3882 | unsigned long nr_scanned; |
4e416953 BS |
3883 | |
3884 | if (order > 0) | |
3885 | return 0; | |
3886 | ||
00918b6a | 3887 | mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone)); |
4e416953 BS |
3888 | /* |
3889 | * This loop can run a while, specially if mem_cgroup's continuously | |
3890 | * keep exceeding their soft limit and putting the system under | |
3891 | * pressure | |
3892 | */ | |
3893 | do { | |
3894 | if (next_mz) | |
3895 | mz = next_mz; | |
3896 | else | |
3897 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
3898 | if (!mz) | |
3899 | break; | |
3900 | ||
0ae5e89c | 3901 | nr_scanned = 0; |
d79154bb | 3902 | reclaimed = mem_cgroup_soft_reclaim(mz->memcg, zone, |
5660048c | 3903 | gfp_mask, &nr_scanned); |
4e416953 | 3904 | nr_reclaimed += reclaimed; |
0ae5e89c | 3905 | *total_scanned += nr_scanned; |
4e416953 BS |
3906 | spin_lock(&mctz->lock); |
3907 | ||
3908 | /* | |
3909 | * If we failed to reclaim anything from this memory cgroup | |
3910 | * it is time to move on to the next cgroup | |
3911 | */ | |
3912 | next_mz = NULL; | |
3913 | if (!reclaimed) { | |
3914 | do { | |
3915 | /* | |
3916 | * Loop until we find yet another one. | |
3917 | * | |
3918 | * By the time we get the soft_limit lock | |
3919 | * again, someone might have aded the | |
3920 | * group back on the RB tree. Iterate to | |
3921 | * make sure we get a different mem. | |
3922 | * mem_cgroup_largest_soft_limit_node returns | |
3923 | * NULL if no other cgroup is present on | |
3924 | * the tree | |
3925 | */ | |
3926 | next_mz = | |
3927 | __mem_cgroup_largest_soft_limit_node(mctz); | |
39cc98f1 | 3928 | if (next_mz == mz) |
d79154bb | 3929 | css_put(&next_mz->memcg->css); |
39cc98f1 | 3930 | else /* next_mz == NULL or other memcg */ |
4e416953 BS |
3931 | break; |
3932 | } while (1); | |
3933 | } | |
d79154bb HD |
3934 | __mem_cgroup_remove_exceeded(mz->memcg, mz, mctz); |
3935 | excess = res_counter_soft_limit_excess(&mz->memcg->res); | |
4e416953 BS |
3936 | /* |
3937 | * One school of thought says that we should not add | |
3938 | * back the node to the tree if reclaim returns 0. | |
3939 | * But our reclaim could return 0, simply because due | |
3940 | * to priority we are exposing a smaller subset of | |
3941 | * memory to reclaim from. Consider this as a longer | |
3942 | * term TODO. | |
3943 | */ | |
ef8745c1 | 3944 | /* If excess == 0, no tree ops */ |
d79154bb | 3945 | __mem_cgroup_insert_exceeded(mz->memcg, mz, mctz, excess); |
4e416953 | 3946 | spin_unlock(&mctz->lock); |
d79154bb | 3947 | css_put(&mz->memcg->css); |
4e416953 BS |
3948 | loop++; |
3949 | /* | |
3950 | * Could not reclaim anything and there are no more | |
3951 | * mem cgroups to try or we seem to be looping without | |
3952 | * reclaiming anything. | |
3953 | */ | |
3954 | if (!nr_reclaimed && | |
3955 | (next_mz == NULL || | |
3956 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
3957 | break; | |
3958 | } while (!nr_reclaimed); | |
3959 | if (next_mz) | |
d79154bb | 3960 | css_put(&next_mz->memcg->css); |
4e416953 BS |
3961 | return nr_reclaimed; |
3962 | } | |
3963 | ||
2ef37d3f MH |
3964 | /** |
3965 | * mem_cgroup_force_empty_list - clears LRU of a group | |
3966 | * @memcg: group to clear | |
3967 | * @node: NUMA node | |
3968 | * @zid: zone id | |
3969 | * @lru: lru to to clear | |
3970 | * | |
3c935d18 | 3971 | * Traverse a specified page_cgroup list and try to drop them all. This doesn't |
2ef37d3f MH |
3972 | * reclaim the pages page themselves - pages are moved to the parent (or root) |
3973 | * group. | |
cc847582 | 3974 | */ |
2ef37d3f | 3975 | static void mem_cgroup_force_empty_list(struct mem_cgroup *memcg, |
08e552c6 | 3976 | int node, int zid, enum lru_list lru) |
cc847582 | 3977 | { |
bea8c150 | 3978 | struct lruvec *lruvec; |
2ef37d3f | 3979 | unsigned long flags; |
072c56c1 | 3980 | struct list_head *list; |
925b7673 JW |
3981 | struct page *busy; |
3982 | struct zone *zone; | |
072c56c1 | 3983 | |
08e552c6 | 3984 | zone = &NODE_DATA(node)->node_zones[zid]; |
bea8c150 HD |
3985 | lruvec = mem_cgroup_zone_lruvec(zone, memcg); |
3986 | list = &lruvec->lists[lru]; | |
cc847582 | 3987 | |
f817ed48 | 3988 | busy = NULL; |
2ef37d3f | 3989 | do { |
925b7673 | 3990 | struct page_cgroup *pc; |
5564e88b JW |
3991 | struct page *page; |
3992 | ||
08e552c6 | 3993 | spin_lock_irqsave(&zone->lru_lock, flags); |
f817ed48 | 3994 | if (list_empty(list)) { |
08e552c6 | 3995 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
52d4b9ac | 3996 | break; |
f817ed48 | 3997 | } |
925b7673 JW |
3998 | page = list_entry(list->prev, struct page, lru); |
3999 | if (busy == page) { | |
4000 | list_move(&page->lru, list); | |
648bcc77 | 4001 | busy = NULL; |
08e552c6 | 4002 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 KH |
4003 | continue; |
4004 | } | |
08e552c6 | 4005 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 | 4006 | |
925b7673 | 4007 | pc = lookup_page_cgroup(page); |
5564e88b | 4008 | |
3c935d18 | 4009 | if (mem_cgroup_move_parent(page, pc, memcg)) { |
f817ed48 | 4010 | /* found lock contention or "pc" is obsolete. */ |
925b7673 | 4011 | busy = page; |
f817ed48 KH |
4012 | cond_resched(); |
4013 | } else | |
4014 | busy = NULL; | |
2ef37d3f | 4015 | } while (!list_empty(list)); |
cc847582 KH |
4016 | } |
4017 | ||
4018 | /* | |
c26251f9 MH |
4019 | * make mem_cgroup's charge to be 0 if there is no task by moving |
4020 | * all the charges and pages to the parent. | |
cc847582 | 4021 | * This enables deleting this mem_cgroup. |
c26251f9 MH |
4022 | * |
4023 | * Caller is responsible for holding css reference on the memcg. | |
cc847582 | 4024 | */ |
ab5196c2 | 4025 | static void mem_cgroup_reparent_charges(struct mem_cgroup *memcg) |
cc847582 | 4026 | { |
c26251f9 | 4027 | int node, zid; |
f817ed48 | 4028 | |
fce66477 | 4029 | do { |
52d4b9ac KH |
4030 | /* This is for making all *used* pages to be on LRU. */ |
4031 | lru_add_drain_all(); | |
c0ff4b85 | 4032 | drain_all_stock_sync(memcg); |
c0ff4b85 | 4033 | mem_cgroup_start_move(memcg); |
31aaea4a | 4034 | for_each_node_state(node, N_MEMORY) { |
2ef37d3f | 4035 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { |
f156ab93 HD |
4036 | enum lru_list lru; |
4037 | for_each_lru(lru) { | |
2ef37d3f | 4038 | mem_cgroup_force_empty_list(memcg, |
f156ab93 | 4039 | node, zid, lru); |
f817ed48 | 4040 | } |
1ecaab2b | 4041 | } |
f817ed48 | 4042 | } |
c0ff4b85 R |
4043 | mem_cgroup_end_move(memcg); |
4044 | memcg_oom_recover(memcg); | |
52d4b9ac | 4045 | cond_resched(); |
f817ed48 | 4046 | |
2ef37d3f MH |
4047 | /* |
4048 | * This is a safety check because mem_cgroup_force_empty_list | |
4049 | * could have raced with mem_cgroup_replace_page_cache callers | |
4050 | * so the lru seemed empty but the page could have been added | |
4051 | * right after the check. RES_USAGE should be safe as we always | |
4052 | * charge before adding to the LRU. | |
4053 | */ | |
4054 | } while (res_counter_read_u64(&memcg->res, RES_USAGE) > 0); | |
c26251f9 MH |
4055 | } |
4056 | ||
4057 | /* | |
4058 | * Reclaims as many pages from the given memcg as possible and moves | |
4059 | * the rest to the parent. | |
4060 | * | |
4061 | * Caller is responsible for holding css reference for memcg. | |
4062 | */ | |
4063 | static int mem_cgroup_force_empty(struct mem_cgroup *memcg) | |
4064 | { | |
4065 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
4066 | struct cgroup *cgrp = memcg->css.cgroup; | |
f817ed48 | 4067 | |
c1e862c1 | 4068 | /* returns EBUSY if there is a task or if we come here twice. */ |
c26251f9 MH |
4069 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children)) |
4070 | return -EBUSY; | |
4071 | ||
c1e862c1 KH |
4072 | /* we call try-to-free pages for make this cgroup empty */ |
4073 | lru_add_drain_all(); | |
f817ed48 | 4074 | /* try to free all pages in this cgroup */ |
569530fb | 4075 | while (nr_retries && res_counter_read_u64(&memcg->res, RES_USAGE) > 0) { |
f817ed48 | 4076 | int progress; |
c1e862c1 | 4077 | |
c26251f9 MH |
4078 | if (signal_pending(current)) |
4079 | return -EINTR; | |
4080 | ||
c0ff4b85 | 4081 | progress = try_to_free_mem_cgroup_pages(memcg, GFP_KERNEL, |
185efc0f | 4082 | false); |
c1e862c1 | 4083 | if (!progress) { |
f817ed48 | 4084 | nr_retries--; |
c1e862c1 | 4085 | /* maybe some writeback is necessary */ |
8aa7e847 | 4086 | congestion_wait(BLK_RW_ASYNC, HZ/10); |
c1e862c1 | 4087 | } |
f817ed48 KH |
4088 | |
4089 | } | |
08e552c6 | 4090 | lru_add_drain(); |
ab5196c2 MH |
4091 | mem_cgroup_reparent_charges(memcg); |
4092 | ||
4093 | return 0; | |
cc847582 KH |
4094 | } |
4095 | ||
6bbda35c | 4096 | static int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event) |
c1e862c1 | 4097 | { |
c26251f9 MH |
4098 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
4099 | int ret; | |
4100 | ||
d8423011 MH |
4101 | if (mem_cgroup_is_root(memcg)) |
4102 | return -EINVAL; | |
c26251f9 MH |
4103 | css_get(&memcg->css); |
4104 | ret = mem_cgroup_force_empty(memcg); | |
4105 | css_put(&memcg->css); | |
4106 | ||
4107 | return ret; | |
c1e862c1 KH |
4108 | } |
4109 | ||
4110 | ||
18f59ea7 BS |
4111 | static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft) |
4112 | { | |
4113 | return mem_cgroup_from_cont(cont)->use_hierarchy; | |
4114 | } | |
4115 | ||
4116 | static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft, | |
4117 | u64 val) | |
4118 | { | |
4119 | int retval = 0; | |
c0ff4b85 | 4120 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
18f59ea7 | 4121 | struct cgroup *parent = cont->parent; |
c0ff4b85 | 4122 | struct mem_cgroup *parent_memcg = NULL; |
18f59ea7 BS |
4123 | |
4124 | if (parent) | |
c0ff4b85 | 4125 | parent_memcg = mem_cgroup_from_cont(parent); |
18f59ea7 BS |
4126 | |
4127 | cgroup_lock(); | |
567fb435 GC |
4128 | |
4129 | if (memcg->use_hierarchy == val) | |
4130 | goto out; | |
4131 | ||
18f59ea7 | 4132 | /* |
af901ca1 | 4133 | * If parent's use_hierarchy is set, we can't make any modifications |
18f59ea7 BS |
4134 | * in the child subtrees. If it is unset, then the change can |
4135 | * occur, provided the current cgroup has no children. | |
4136 | * | |
4137 | * For the root cgroup, parent_mem is NULL, we allow value to be | |
4138 | * set if there are no children. | |
4139 | */ | |
c0ff4b85 | 4140 | if ((!parent_memcg || !parent_memcg->use_hierarchy) && |
18f59ea7 BS |
4141 | (val == 1 || val == 0)) { |
4142 | if (list_empty(&cont->children)) | |
c0ff4b85 | 4143 | memcg->use_hierarchy = val; |
18f59ea7 BS |
4144 | else |
4145 | retval = -EBUSY; | |
4146 | } else | |
4147 | retval = -EINVAL; | |
567fb435 GC |
4148 | |
4149 | out: | |
18f59ea7 BS |
4150 | cgroup_unlock(); |
4151 | ||
4152 | return retval; | |
4153 | } | |
4154 | ||
0c3e73e8 | 4155 | |
c0ff4b85 | 4156 | static unsigned long mem_cgroup_recursive_stat(struct mem_cgroup *memcg, |
7a159cc9 | 4157 | enum mem_cgroup_stat_index idx) |
0c3e73e8 | 4158 | { |
7d74b06f | 4159 | struct mem_cgroup *iter; |
7a159cc9 | 4160 | long val = 0; |
0c3e73e8 | 4161 | |
7a159cc9 | 4162 | /* Per-cpu values can be negative, use a signed accumulator */ |
c0ff4b85 | 4163 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f KH |
4164 | val += mem_cgroup_read_stat(iter, idx); |
4165 | ||
4166 | if (val < 0) /* race ? */ | |
4167 | val = 0; | |
4168 | return val; | |
0c3e73e8 BS |
4169 | } |
4170 | ||
c0ff4b85 | 4171 | static inline u64 mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) |
104f3928 | 4172 | { |
7d74b06f | 4173 | u64 val; |
104f3928 | 4174 | |
c0ff4b85 | 4175 | if (!mem_cgroup_is_root(memcg)) { |
104f3928 | 4176 | if (!swap) |
65c64ce8 | 4177 | return res_counter_read_u64(&memcg->res, RES_USAGE); |
104f3928 | 4178 | else |
65c64ce8 | 4179 | return res_counter_read_u64(&memcg->memsw, RES_USAGE); |
104f3928 KS |
4180 | } |
4181 | ||
c0ff4b85 R |
4182 | val = mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_CACHE); |
4183 | val += mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_RSS); | |
104f3928 | 4184 | |
7d74b06f | 4185 | if (swap) |
bff6bb83 | 4186 | val += mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_SWAP); |
104f3928 KS |
4187 | |
4188 | return val << PAGE_SHIFT; | |
4189 | } | |
4190 | ||
af36f906 TH |
4191 | static ssize_t mem_cgroup_read(struct cgroup *cont, struct cftype *cft, |
4192 | struct file *file, char __user *buf, | |
4193 | size_t nbytes, loff_t *ppos) | |
8cdea7c0 | 4194 | { |
c0ff4b85 | 4195 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
af36f906 | 4196 | char str[64]; |
104f3928 | 4197 | u64 val; |
86ae53e1 GC |
4198 | int name, len; |
4199 | enum res_type type; | |
8c7c6e34 KH |
4200 | |
4201 | type = MEMFILE_TYPE(cft->private); | |
4202 | name = MEMFILE_ATTR(cft->private); | |
af36f906 TH |
4203 | |
4204 | if (!do_swap_account && type == _MEMSWAP) | |
4205 | return -EOPNOTSUPP; | |
4206 | ||
8c7c6e34 KH |
4207 | switch (type) { |
4208 | case _MEM: | |
104f3928 | 4209 | if (name == RES_USAGE) |
c0ff4b85 | 4210 | val = mem_cgroup_usage(memcg, false); |
104f3928 | 4211 | else |
c0ff4b85 | 4212 | val = res_counter_read_u64(&memcg->res, name); |
8c7c6e34 KH |
4213 | break; |
4214 | case _MEMSWAP: | |
104f3928 | 4215 | if (name == RES_USAGE) |
c0ff4b85 | 4216 | val = mem_cgroup_usage(memcg, true); |
104f3928 | 4217 | else |
c0ff4b85 | 4218 | val = res_counter_read_u64(&memcg->memsw, name); |
8c7c6e34 | 4219 | break; |
510fc4e1 GC |
4220 | case _KMEM: |
4221 | val = res_counter_read_u64(&memcg->kmem, name); | |
4222 | break; | |
8c7c6e34 KH |
4223 | default: |
4224 | BUG(); | |
8c7c6e34 | 4225 | } |
af36f906 TH |
4226 | |
4227 | len = scnprintf(str, sizeof(str), "%llu\n", (unsigned long long)val); | |
4228 | return simple_read_from_buffer(buf, nbytes, ppos, str, len); | |
8cdea7c0 | 4229 | } |
510fc4e1 GC |
4230 | |
4231 | static int memcg_update_kmem_limit(struct cgroup *cont, u64 val) | |
4232 | { | |
4233 | int ret = -EINVAL; | |
4234 | #ifdef CONFIG_MEMCG_KMEM | |
a8964b9b GC |
4235 | bool must_inc_static_branch = false; |
4236 | ||
510fc4e1 GC |
4237 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
4238 | /* | |
4239 | * For simplicity, we won't allow this to be disabled. It also can't | |
4240 | * be changed if the cgroup has children already, or if tasks had | |
4241 | * already joined. | |
4242 | * | |
4243 | * If tasks join before we set the limit, a person looking at | |
4244 | * kmem.usage_in_bytes will have no way to determine when it took | |
4245 | * place, which makes the value quite meaningless. | |
4246 | * | |
4247 | * After it first became limited, changes in the value of the limit are | |
4248 | * of course permitted. | |
4249 | * | |
4250 | * Taking the cgroup_lock is really offensive, but it is so far the only | |
4251 | * way to guarantee that no children will appear. There are plenty of | |
4252 | * other offenders, and they should all go away. Fine grained locking | |
4253 | * is probably the way to go here. When we are fully hierarchical, we | |
4254 | * can also get rid of the use_hierarchy check. | |
4255 | */ | |
4256 | cgroup_lock(); | |
4257 | mutex_lock(&set_limit_mutex); | |
4258 | if (!memcg->kmem_account_flags && val != RESOURCE_MAX) { | |
4259 | if (cgroup_task_count(cont) || (memcg->use_hierarchy && | |
4260 | !list_empty(&cont->children))) { | |
4261 | ret = -EBUSY; | |
4262 | goto out; | |
4263 | } | |
4264 | ret = res_counter_set_limit(&memcg->kmem, val); | |
4265 | VM_BUG_ON(ret); | |
4266 | ||
a8964b9b GC |
4267 | /* |
4268 | * After this point, kmem_accounted (that we test atomically in | |
4269 | * the beginning of this conditional), is no longer 0. This | |
4270 | * guarantees only one process will set the following boolean | |
4271 | * to true. We don't need test_and_set because we're protected | |
4272 | * by the set_limit_mutex anyway. | |
4273 | */ | |
4274 | memcg_kmem_set_activated(memcg); | |
4275 | must_inc_static_branch = true; | |
7de37682 GC |
4276 | /* |
4277 | * kmem charges can outlive the cgroup. In the case of slab | |
4278 | * pages, for instance, a page contain objects from various | |
4279 | * processes, so it is unfeasible to migrate them away. We | |
4280 | * need to reference count the memcg because of that. | |
4281 | */ | |
4282 | mem_cgroup_get(memcg); | |
510fc4e1 GC |
4283 | } else |
4284 | ret = res_counter_set_limit(&memcg->kmem, val); | |
4285 | out: | |
4286 | mutex_unlock(&set_limit_mutex); | |
4287 | cgroup_unlock(); | |
a8964b9b GC |
4288 | |
4289 | /* | |
4290 | * We are by now familiar with the fact that we can't inc the static | |
4291 | * branch inside cgroup_lock. See disarm functions for details. A | |
4292 | * worker here is overkill, but also wrong: After the limit is set, we | |
4293 | * must start accounting right away. Since this operation can't fail, | |
4294 | * we can safely defer it to here - no rollback will be needed. | |
4295 | * | |
4296 | * The boolean used to control this is also safe, because | |
4297 | * KMEM_ACCOUNTED_ACTIVATED guarantees that only one process will be | |
4298 | * able to set it to true; | |
4299 | */ | |
4300 | if (must_inc_static_branch) { | |
4301 | static_key_slow_inc(&memcg_kmem_enabled_key); | |
4302 | /* | |
4303 | * setting the active bit after the inc will guarantee no one | |
4304 | * starts accounting before all call sites are patched | |
4305 | */ | |
4306 | memcg_kmem_set_active(memcg); | |
4307 | } | |
4308 | ||
510fc4e1 GC |
4309 | #endif |
4310 | return ret; | |
4311 | } | |
4312 | ||
4313 | static void memcg_propagate_kmem(struct mem_cgroup *memcg) | |
4314 | { | |
4315 | struct mem_cgroup *parent = parent_mem_cgroup(memcg); | |
4316 | if (!parent) | |
4317 | return; | |
4318 | memcg->kmem_account_flags = parent->kmem_account_flags; | |
7de37682 | 4319 | #ifdef CONFIG_MEMCG_KMEM |
a8964b9b GC |
4320 | /* |
4321 | * When that happen, we need to disable the static branch only on those | |
4322 | * memcgs that enabled it. To achieve this, we would be forced to | |
4323 | * complicate the code by keeping track of which memcgs were the ones | |
4324 | * that actually enabled limits, and which ones got it from its | |
4325 | * parents. | |
4326 | * | |
4327 | * It is a lot simpler just to do static_key_slow_inc() on every child | |
4328 | * that is accounted. | |
4329 | */ | |
4330 | if (memcg_kmem_is_active(memcg)) { | |
7de37682 | 4331 | mem_cgroup_get(memcg); |
a8964b9b GC |
4332 | static_key_slow_inc(&memcg_kmem_enabled_key); |
4333 | } | |
7de37682 | 4334 | #endif |
510fc4e1 GC |
4335 | } |
4336 | ||
628f4235 KH |
4337 | /* |
4338 | * The user of this function is... | |
4339 | * RES_LIMIT. | |
4340 | */ | |
856c13aa PM |
4341 | static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, |
4342 | const char *buffer) | |
8cdea7c0 | 4343 | { |
628f4235 | 4344 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
86ae53e1 GC |
4345 | enum res_type type; |
4346 | int name; | |
628f4235 KH |
4347 | unsigned long long val; |
4348 | int ret; | |
4349 | ||
8c7c6e34 KH |
4350 | type = MEMFILE_TYPE(cft->private); |
4351 | name = MEMFILE_ATTR(cft->private); | |
af36f906 TH |
4352 | |
4353 | if (!do_swap_account && type == _MEMSWAP) | |
4354 | return -EOPNOTSUPP; | |
4355 | ||
8c7c6e34 | 4356 | switch (name) { |
628f4235 | 4357 | case RES_LIMIT: |
4b3bde4c BS |
4358 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
4359 | ret = -EINVAL; | |
4360 | break; | |
4361 | } | |
628f4235 KH |
4362 | /* This function does all necessary parse...reuse it */ |
4363 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
8c7c6e34 KH |
4364 | if (ret) |
4365 | break; | |
4366 | if (type == _MEM) | |
628f4235 | 4367 | ret = mem_cgroup_resize_limit(memcg, val); |
510fc4e1 | 4368 | else if (type == _MEMSWAP) |
8c7c6e34 | 4369 | ret = mem_cgroup_resize_memsw_limit(memcg, val); |
510fc4e1 GC |
4370 | else if (type == _KMEM) |
4371 | ret = memcg_update_kmem_limit(cont, val); | |
4372 | else | |
4373 | return -EINVAL; | |
628f4235 | 4374 | break; |
296c81d8 BS |
4375 | case RES_SOFT_LIMIT: |
4376 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
4377 | if (ret) | |
4378 | break; | |
4379 | /* | |
4380 | * For memsw, soft limits are hard to implement in terms | |
4381 | * of semantics, for now, we support soft limits for | |
4382 | * control without swap | |
4383 | */ | |
4384 | if (type == _MEM) | |
4385 | ret = res_counter_set_soft_limit(&memcg->res, val); | |
4386 | else | |
4387 | ret = -EINVAL; | |
4388 | break; | |
628f4235 KH |
4389 | default: |
4390 | ret = -EINVAL; /* should be BUG() ? */ | |
4391 | break; | |
4392 | } | |
4393 | return ret; | |
8cdea7c0 BS |
4394 | } |
4395 | ||
fee7b548 KH |
4396 | static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, |
4397 | unsigned long long *mem_limit, unsigned long long *memsw_limit) | |
4398 | { | |
4399 | struct cgroup *cgroup; | |
4400 | unsigned long long min_limit, min_memsw_limit, tmp; | |
4401 | ||
4402 | min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
4403 | min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
4404 | cgroup = memcg->css.cgroup; | |
4405 | if (!memcg->use_hierarchy) | |
4406 | goto out; | |
4407 | ||
4408 | while (cgroup->parent) { | |
4409 | cgroup = cgroup->parent; | |
4410 | memcg = mem_cgroup_from_cont(cgroup); | |
4411 | if (!memcg->use_hierarchy) | |
4412 | break; | |
4413 | tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
4414 | min_limit = min(min_limit, tmp); | |
4415 | tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
4416 | min_memsw_limit = min(min_memsw_limit, tmp); | |
4417 | } | |
4418 | out: | |
4419 | *mem_limit = min_limit; | |
4420 | *memsw_limit = min_memsw_limit; | |
fee7b548 KH |
4421 | } |
4422 | ||
29f2a4da | 4423 | static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) |
c84872e1 | 4424 | { |
af36f906 | 4425 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
86ae53e1 GC |
4426 | int name; |
4427 | enum res_type type; | |
c84872e1 | 4428 | |
8c7c6e34 KH |
4429 | type = MEMFILE_TYPE(event); |
4430 | name = MEMFILE_ATTR(event); | |
af36f906 TH |
4431 | |
4432 | if (!do_swap_account && type == _MEMSWAP) | |
4433 | return -EOPNOTSUPP; | |
4434 | ||
8c7c6e34 | 4435 | switch (name) { |
29f2a4da | 4436 | case RES_MAX_USAGE: |
8c7c6e34 | 4437 | if (type == _MEM) |
c0ff4b85 | 4438 | res_counter_reset_max(&memcg->res); |
510fc4e1 | 4439 | else if (type == _MEMSWAP) |
c0ff4b85 | 4440 | res_counter_reset_max(&memcg->memsw); |
510fc4e1 GC |
4441 | else if (type == _KMEM) |
4442 | res_counter_reset_max(&memcg->kmem); | |
4443 | else | |
4444 | return -EINVAL; | |
29f2a4da PE |
4445 | break; |
4446 | case RES_FAILCNT: | |
8c7c6e34 | 4447 | if (type == _MEM) |
c0ff4b85 | 4448 | res_counter_reset_failcnt(&memcg->res); |
510fc4e1 | 4449 | else if (type == _MEMSWAP) |
c0ff4b85 | 4450 | res_counter_reset_failcnt(&memcg->memsw); |
510fc4e1 GC |
4451 | else if (type == _KMEM) |
4452 | res_counter_reset_failcnt(&memcg->kmem); | |
4453 | else | |
4454 | return -EINVAL; | |
29f2a4da PE |
4455 | break; |
4456 | } | |
f64c3f54 | 4457 | |
85cc59db | 4458 | return 0; |
c84872e1 PE |
4459 | } |
4460 | ||
7dc74be0 DN |
4461 | static u64 mem_cgroup_move_charge_read(struct cgroup *cgrp, |
4462 | struct cftype *cft) | |
4463 | { | |
4464 | return mem_cgroup_from_cont(cgrp)->move_charge_at_immigrate; | |
4465 | } | |
4466 | ||
02491447 | 4467 | #ifdef CONFIG_MMU |
7dc74be0 DN |
4468 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, |
4469 | struct cftype *cft, u64 val) | |
4470 | { | |
c0ff4b85 | 4471 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
7dc74be0 DN |
4472 | |
4473 | if (val >= (1 << NR_MOVE_TYPE)) | |
4474 | return -EINVAL; | |
4475 | /* | |
4476 | * We check this value several times in both in can_attach() and | |
4477 | * attach(), so we need cgroup lock to prevent this value from being | |
4478 | * inconsistent. | |
4479 | */ | |
4480 | cgroup_lock(); | |
c0ff4b85 | 4481 | memcg->move_charge_at_immigrate = val; |
7dc74be0 DN |
4482 | cgroup_unlock(); |
4483 | ||
4484 | return 0; | |
4485 | } | |
02491447 DN |
4486 | #else |
4487 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, | |
4488 | struct cftype *cft, u64 val) | |
4489 | { | |
4490 | return -ENOSYS; | |
4491 | } | |
4492 | #endif | |
7dc74be0 | 4493 | |
406eb0c9 | 4494 | #ifdef CONFIG_NUMA |
ab215884 | 4495 | static int memcg_numa_stat_show(struct cgroup *cont, struct cftype *cft, |
fada52ca | 4496 | struct seq_file *m) |
406eb0c9 YH |
4497 | { |
4498 | int nid; | |
4499 | unsigned long total_nr, file_nr, anon_nr, unevictable_nr; | |
4500 | unsigned long node_nr; | |
d79154bb | 4501 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
406eb0c9 | 4502 | |
d79154bb | 4503 | total_nr = mem_cgroup_nr_lru_pages(memcg, LRU_ALL); |
406eb0c9 | 4504 | seq_printf(m, "total=%lu", total_nr); |
31aaea4a | 4505 | for_each_node_state(nid, N_MEMORY) { |
d79154bb | 4506 | node_nr = mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL); |
406eb0c9 YH |
4507 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4508 | } | |
4509 | seq_putc(m, '\n'); | |
4510 | ||
d79154bb | 4511 | file_nr = mem_cgroup_nr_lru_pages(memcg, LRU_ALL_FILE); |
406eb0c9 | 4512 | seq_printf(m, "file=%lu", file_nr); |
31aaea4a | 4513 | for_each_node_state(nid, N_MEMORY) { |
d79154bb | 4514 | node_nr = mem_cgroup_node_nr_lru_pages(memcg, nid, |
bb2a0de9 | 4515 | LRU_ALL_FILE); |
406eb0c9 YH |
4516 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4517 | } | |
4518 | seq_putc(m, '\n'); | |
4519 | ||
d79154bb | 4520 | anon_nr = mem_cgroup_nr_lru_pages(memcg, LRU_ALL_ANON); |
406eb0c9 | 4521 | seq_printf(m, "anon=%lu", anon_nr); |
31aaea4a | 4522 | for_each_node_state(nid, N_MEMORY) { |
d79154bb | 4523 | node_nr = mem_cgroup_node_nr_lru_pages(memcg, nid, |
bb2a0de9 | 4524 | LRU_ALL_ANON); |
406eb0c9 YH |
4525 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4526 | } | |
4527 | seq_putc(m, '\n'); | |
4528 | ||
d79154bb | 4529 | unevictable_nr = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_UNEVICTABLE)); |
406eb0c9 | 4530 | seq_printf(m, "unevictable=%lu", unevictable_nr); |
31aaea4a | 4531 | for_each_node_state(nid, N_MEMORY) { |
d79154bb | 4532 | node_nr = mem_cgroup_node_nr_lru_pages(memcg, nid, |
bb2a0de9 | 4533 | BIT(LRU_UNEVICTABLE)); |
406eb0c9 YH |
4534 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4535 | } | |
4536 | seq_putc(m, '\n'); | |
4537 | return 0; | |
4538 | } | |
4539 | #endif /* CONFIG_NUMA */ | |
4540 | ||
af7c4b0e JW |
4541 | static const char * const mem_cgroup_lru_names[] = { |
4542 | "inactive_anon", | |
4543 | "active_anon", | |
4544 | "inactive_file", | |
4545 | "active_file", | |
4546 | "unevictable", | |
4547 | }; | |
4548 | ||
4549 | static inline void mem_cgroup_lru_names_not_uptodate(void) | |
4550 | { | |
4551 | BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_lru_names) != NR_LRU_LISTS); | |
4552 | } | |
4553 | ||
ab215884 | 4554 | static int memcg_stat_show(struct cgroup *cont, struct cftype *cft, |
78ccf5b5 | 4555 | struct seq_file *m) |
d2ceb9b7 | 4556 | { |
d79154bb | 4557 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
af7c4b0e JW |
4558 | struct mem_cgroup *mi; |
4559 | unsigned int i; | |
406eb0c9 | 4560 | |
af7c4b0e | 4561 | for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) { |
bff6bb83 | 4562 | if (i == MEM_CGROUP_STAT_SWAP && !do_swap_account) |
1dd3a273 | 4563 | continue; |
af7c4b0e JW |
4564 | seq_printf(m, "%s %ld\n", mem_cgroup_stat_names[i], |
4565 | mem_cgroup_read_stat(memcg, i) * PAGE_SIZE); | |
1dd3a273 | 4566 | } |
7b854121 | 4567 | |
af7c4b0e JW |
4568 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) |
4569 | seq_printf(m, "%s %lu\n", mem_cgroup_events_names[i], | |
4570 | mem_cgroup_read_events(memcg, i)); | |
4571 | ||
4572 | for (i = 0; i < NR_LRU_LISTS; i++) | |
4573 | seq_printf(m, "%s %lu\n", mem_cgroup_lru_names[i], | |
4574 | mem_cgroup_nr_lru_pages(memcg, BIT(i)) * PAGE_SIZE); | |
4575 | ||
14067bb3 | 4576 | /* Hierarchical information */ |
fee7b548 KH |
4577 | { |
4578 | unsigned long long limit, memsw_limit; | |
d79154bb | 4579 | memcg_get_hierarchical_limit(memcg, &limit, &memsw_limit); |
78ccf5b5 | 4580 | seq_printf(m, "hierarchical_memory_limit %llu\n", limit); |
fee7b548 | 4581 | if (do_swap_account) |
78ccf5b5 JW |
4582 | seq_printf(m, "hierarchical_memsw_limit %llu\n", |
4583 | memsw_limit); | |
fee7b548 | 4584 | } |
7f016ee8 | 4585 | |
af7c4b0e JW |
4586 | for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) { |
4587 | long long val = 0; | |
4588 | ||
bff6bb83 | 4589 | if (i == MEM_CGROUP_STAT_SWAP && !do_swap_account) |
1dd3a273 | 4590 | continue; |
af7c4b0e JW |
4591 | for_each_mem_cgroup_tree(mi, memcg) |
4592 | val += mem_cgroup_read_stat(mi, i) * PAGE_SIZE; | |
4593 | seq_printf(m, "total_%s %lld\n", mem_cgroup_stat_names[i], val); | |
4594 | } | |
4595 | ||
4596 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) { | |
4597 | unsigned long long val = 0; | |
4598 | ||
4599 | for_each_mem_cgroup_tree(mi, memcg) | |
4600 | val += mem_cgroup_read_events(mi, i); | |
4601 | seq_printf(m, "total_%s %llu\n", | |
4602 | mem_cgroup_events_names[i], val); | |
4603 | } | |
4604 | ||
4605 | for (i = 0; i < NR_LRU_LISTS; i++) { | |
4606 | unsigned long long val = 0; | |
4607 | ||
4608 | for_each_mem_cgroup_tree(mi, memcg) | |
4609 | val += mem_cgroup_nr_lru_pages(mi, BIT(i)) * PAGE_SIZE; | |
4610 | seq_printf(m, "total_%s %llu\n", mem_cgroup_lru_names[i], val); | |
1dd3a273 | 4611 | } |
14067bb3 | 4612 | |
7f016ee8 | 4613 | #ifdef CONFIG_DEBUG_VM |
7f016ee8 KM |
4614 | { |
4615 | int nid, zid; | |
4616 | struct mem_cgroup_per_zone *mz; | |
89abfab1 | 4617 | struct zone_reclaim_stat *rstat; |
7f016ee8 KM |
4618 | unsigned long recent_rotated[2] = {0, 0}; |
4619 | unsigned long recent_scanned[2] = {0, 0}; | |
4620 | ||
4621 | for_each_online_node(nid) | |
4622 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
d79154bb | 4623 | mz = mem_cgroup_zoneinfo(memcg, nid, zid); |
89abfab1 | 4624 | rstat = &mz->lruvec.reclaim_stat; |
7f016ee8 | 4625 | |
89abfab1 HD |
4626 | recent_rotated[0] += rstat->recent_rotated[0]; |
4627 | recent_rotated[1] += rstat->recent_rotated[1]; | |
4628 | recent_scanned[0] += rstat->recent_scanned[0]; | |
4629 | recent_scanned[1] += rstat->recent_scanned[1]; | |
7f016ee8 | 4630 | } |
78ccf5b5 JW |
4631 | seq_printf(m, "recent_rotated_anon %lu\n", recent_rotated[0]); |
4632 | seq_printf(m, "recent_rotated_file %lu\n", recent_rotated[1]); | |
4633 | seq_printf(m, "recent_scanned_anon %lu\n", recent_scanned[0]); | |
4634 | seq_printf(m, "recent_scanned_file %lu\n", recent_scanned[1]); | |
7f016ee8 KM |
4635 | } |
4636 | #endif | |
4637 | ||
d2ceb9b7 KH |
4638 | return 0; |
4639 | } | |
4640 | ||
a7885eb8 KM |
4641 | static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft) |
4642 | { | |
4643 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4644 | ||
1f4c025b | 4645 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
4646 | } |
4647 | ||
4648 | static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, | |
4649 | u64 val) | |
4650 | { | |
4651 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4652 | struct mem_cgroup *parent; | |
068b38c1 | 4653 | |
a7885eb8 KM |
4654 | if (val > 100) |
4655 | return -EINVAL; | |
4656 | ||
4657 | if (cgrp->parent == NULL) | |
4658 | return -EINVAL; | |
4659 | ||
4660 | parent = mem_cgroup_from_cont(cgrp->parent); | |
068b38c1 LZ |
4661 | |
4662 | cgroup_lock(); | |
4663 | ||
a7885eb8 KM |
4664 | /* If under hierarchy, only empty-root can set this value */ |
4665 | if ((parent->use_hierarchy) || | |
068b38c1 LZ |
4666 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
4667 | cgroup_unlock(); | |
a7885eb8 | 4668 | return -EINVAL; |
068b38c1 | 4669 | } |
a7885eb8 | 4670 | |
a7885eb8 | 4671 | memcg->swappiness = val; |
a7885eb8 | 4672 | |
068b38c1 LZ |
4673 | cgroup_unlock(); |
4674 | ||
a7885eb8 KM |
4675 | return 0; |
4676 | } | |
4677 | ||
2e72b634 KS |
4678 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
4679 | { | |
4680 | struct mem_cgroup_threshold_ary *t; | |
4681 | u64 usage; | |
4682 | int i; | |
4683 | ||
4684 | rcu_read_lock(); | |
4685 | if (!swap) | |
2c488db2 | 4686 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 4687 | else |
2c488db2 | 4688 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
4689 | |
4690 | if (!t) | |
4691 | goto unlock; | |
4692 | ||
4693 | usage = mem_cgroup_usage(memcg, swap); | |
4694 | ||
4695 | /* | |
748dad36 | 4696 | * current_threshold points to threshold just below or equal to usage. |
2e72b634 KS |
4697 | * If it's not true, a threshold was crossed after last |
4698 | * call of __mem_cgroup_threshold(). | |
4699 | */ | |
5407a562 | 4700 | i = t->current_threshold; |
2e72b634 KS |
4701 | |
4702 | /* | |
4703 | * Iterate backward over array of thresholds starting from | |
4704 | * current_threshold and check if a threshold is crossed. | |
4705 | * If none of thresholds below usage is crossed, we read | |
4706 | * only one element of the array here. | |
4707 | */ | |
4708 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
4709 | eventfd_signal(t->entries[i].eventfd, 1); | |
4710 | ||
4711 | /* i = current_threshold + 1 */ | |
4712 | i++; | |
4713 | ||
4714 | /* | |
4715 | * Iterate forward over array of thresholds starting from | |
4716 | * current_threshold+1 and check if a threshold is crossed. | |
4717 | * If none of thresholds above usage is crossed, we read | |
4718 | * only one element of the array here. | |
4719 | */ | |
4720 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
4721 | eventfd_signal(t->entries[i].eventfd, 1); | |
4722 | ||
4723 | /* Update current_threshold */ | |
5407a562 | 4724 | t->current_threshold = i - 1; |
2e72b634 KS |
4725 | unlock: |
4726 | rcu_read_unlock(); | |
4727 | } | |
4728 | ||
4729 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
4730 | { | |
ad4ca5f4 KS |
4731 | while (memcg) { |
4732 | __mem_cgroup_threshold(memcg, false); | |
4733 | if (do_swap_account) | |
4734 | __mem_cgroup_threshold(memcg, true); | |
4735 | ||
4736 | memcg = parent_mem_cgroup(memcg); | |
4737 | } | |
2e72b634 KS |
4738 | } |
4739 | ||
4740 | static int compare_thresholds(const void *a, const void *b) | |
4741 | { | |
4742 | const struct mem_cgroup_threshold *_a = a; | |
4743 | const struct mem_cgroup_threshold *_b = b; | |
4744 | ||
4745 | return _a->threshold - _b->threshold; | |
4746 | } | |
4747 | ||
c0ff4b85 | 4748 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg) |
9490ff27 KH |
4749 | { |
4750 | struct mem_cgroup_eventfd_list *ev; | |
4751 | ||
c0ff4b85 | 4752 | list_for_each_entry(ev, &memcg->oom_notify, list) |
9490ff27 KH |
4753 | eventfd_signal(ev->eventfd, 1); |
4754 | return 0; | |
4755 | } | |
4756 | ||
c0ff4b85 | 4757 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) |
9490ff27 | 4758 | { |
7d74b06f KH |
4759 | struct mem_cgroup *iter; |
4760 | ||
c0ff4b85 | 4761 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 4762 | mem_cgroup_oom_notify_cb(iter); |
9490ff27 KH |
4763 | } |
4764 | ||
4765 | static int mem_cgroup_usage_register_event(struct cgroup *cgrp, | |
4766 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
2e72b634 KS |
4767 | { |
4768 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4769 | struct mem_cgroup_thresholds *thresholds; |
4770 | struct mem_cgroup_threshold_ary *new; | |
86ae53e1 | 4771 | enum res_type type = MEMFILE_TYPE(cft->private); |
2e72b634 | 4772 | u64 threshold, usage; |
2c488db2 | 4773 | int i, size, ret; |
2e72b634 KS |
4774 | |
4775 | ret = res_counter_memparse_write_strategy(args, &threshold); | |
4776 | if (ret) | |
4777 | return ret; | |
4778 | ||
4779 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 4780 | |
2e72b634 | 4781 | if (type == _MEM) |
2c488db2 | 4782 | thresholds = &memcg->thresholds; |
2e72b634 | 4783 | else if (type == _MEMSWAP) |
2c488db2 | 4784 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4785 | else |
4786 | BUG(); | |
4787 | ||
4788 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4789 | ||
4790 | /* Check if a threshold crossed before adding a new one */ | |
2c488db2 | 4791 | if (thresholds->primary) |
2e72b634 KS |
4792 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4793 | ||
2c488db2 | 4794 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
4795 | |
4796 | /* Allocate memory for new array of thresholds */ | |
2c488db2 | 4797 | new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold), |
2e72b634 | 4798 | GFP_KERNEL); |
2c488db2 | 4799 | if (!new) { |
2e72b634 KS |
4800 | ret = -ENOMEM; |
4801 | goto unlock; | |
4802 | } | |
2c488db2 | 4803 | new->size = size; |
2e72b634 KS |
4804 | |
4805 | /* Copy thresholds (if any) to new array */ | |
2c488db2 KS |
4806 | if (thresholds->primary) { |
4807 | memcpy(new->entries, thresholds->primary->entries, (size - 1) * | |
2e72b634 | 4808 | sizeof(struct mem_cgroup_threshold)); |
2c488db2 KS |
4809 | } |
4810 | ||
2e72b634 | 4811 | /* Add new threshold */ |
2c488db2 KS |
4812 | new->entries[size - 1].eventfd = eventfd; |
4813 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
4814 | |
4815 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
2c488db2 | 4816 | sort(new->entries, size, sizeof(struct mem_cgroup_threshold), |
2e72b634 KS |
4817 | compare_thresholds, NULL); |
4818 | ||
4819 | /* Find current threshold */ | |
2c488db2 | 4820 | new->current_threshold = -1; |
2e72b634 | 4821 | for (i = 0; i < size; i++) { |
748dad36 | 4822 | if (new->entries[i].threshold <= usage) { |
2e72b634 | 4823 | /* |
2c488db2 KS |
4824 | * new->current_threshold will not be used until |
4825 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
4826 | * it here. |
4827 | */ | |
2c488db2 | 4828 | ++new->current_threshold; |
748dad36 SZ |
4829 | } else |
4830 | break; | |
2e72b634 KS |
4831 | } |
4832 | ||
2c488db2 KS |
4833 | /* Free old spare buffer and save old primary buffer as spare */ |
4834 | kfree(thresholds->spare); | |
4835 | thresholds->spare = thresholds->primary; | |
4836 | ||
4837 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4838 | |
907860ed | 4839 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4840 | synchronize_rcu(); |
4841 | ||
2e72b634 KS |
4842 | unlock: |
4843 | mutex_unlock(&memcg->thresholds_lock); | |
4844 | ||
4845 | return ret; | |
4846 | } | |
4847 | ||
907860ed | 4848 | static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp, |
9490ff27 | 4849 | struct cftype *cft, struct eventfd_ctx *eventfd) |
2e72b634 KS |
4850 | { |
4851 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4852 | struct mem_cgroup_thresholds *thresholds; |
4853 | struct mem_cgroup_threshold_ary *new; | |
86ae53e1 | 4854 | enum res_type type = MEMFILE_TYPE(cft->private); |
2e72b634 | 4855 | u64 usage; |
2c488db2 | 4856 | int i, j, size; |
2e72b634 KS |
4857 | |
4858 | mutex_lock(&memcg->thresholds_lock); | |
4859 | if (type == _MEM) | |
2c488db2 | 4860 | thresholds = &memcg->thresholds; |
2e72b634 | 4861 | else if (type == _MEMSWAP) |
2c488db2 | 4862 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4863 | else |
4864 | BUG(); | |
4865 | ||
371528ca AV |
4866 | if (!thresholds->primary) |
4867 | goto unlock; | |
4868 | ||
2e72b634 KS |
4869 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); |
4870 | ||
4871 | /* Check if a threshold crossed before removing */ | |
4872 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
4873 | ||
4874 | /* Calculate new number of threshold */ | |
2c488db2 KS |
4875 | size = 0; |
4876 | for (i = 0; i < thresholds->primary->size; i++) { | |
4877 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 KS |
4878 | size++; |
4879 | } | |
4880 | ||
2c488db2 | 4881 | new = thresholds->spare; |
907860ed | 4882 | |
2e72b634 KS |
4883 | /* Set thresholds array to NULL if we don't have thresholds */ |
4884 | if (!size) { | |
2c488db2 KS |
4885 | kfree(new); |
4886 | new = NULL; | |
907860ed | 4887 | goto swap_buffers; |
2e72b634 KS |
4888 | } |
4889 | ||
2c488db2 | 4890 | new->size = size; |
2e72b634 KS |
4891 | |
4892 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
4893 | new->current_threshold = -1; |
4894 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
4895 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
4896 | continue; |
4897 | ||
2c488db2 | 4898 | new->entries[j] = thresholds->primary->entries[i]; |
748dad36 | 4899 | if (new->entries[j].threshold <= usage) { |
2e72b634 | 4900 | /* |
2c488db2 | 4901 | * new->current_threshold will not be used |
2e72b634 KS |
4902 | * until rcu_assign_pointer(), so it's safe to increment |
4903 | * it here. | |
4904 | */ | |
2c488db2 | 4905 | ++new->current_threshold; |
2e72b634 KS |
4906 | } |
4907 | j++; | |
4908 | } | |
4909 | ||
907860ed | 4910 | swap_buffers: |
2c488db2 KS |
4911 | /* Swap primary and spare array */ |
4912 | thresholds->spare = thresholds->primary; | |
8c757763 SZ |
4913 | /* If all events are unregistered, free the spare array */ |
4914 | if (!new) { | |
4915 | kfree(thresholds->spare); | |
4916 | thresholds->spare = NULL; | |
4917 | } | |
4918 | ||
2c488db2 | 4919 | rcu_assign_pointer(thresholds->primary, new); |
2e72b634 | 4920 | |
907860ed | 4921 | /* To be sure that nobody uses thresholds */ |
2e72b634 | 4922 | synchronize_rcu(); |
371528ca | 4923 | unlock: |
2e72b634 | 4924 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 4925 | } |
c1e862c1 | 4926 | |
9490ff27 KH |
4927 | static int mem_cgroup_oom_register_event(struct cgroup *cgrp, |
4928 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
4929 | { | |
4930 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4931 | struct mem_cgroup_eventfd_list *event; | |
86ae53e1 | 4932 | enum res_type type = MEMFILE_TYPE(cft->private); |
9490ff27 KH |
4933 | |
4934 | BUG_ON(type != _OOM_TYPE); | |
4935 | event = kmalloc(sizeof(*event), GFP_KERNEL); | |
4936 | if (!event) | |
4937 | return -ENOMEM; | |
4938 | ||
1af8efe9 | 4939 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4940 | |
4941 | event->eventfd = eventfd; | |
4942 | list_add(&event->list, &memcg->oom_notify); | |
4943 | ||
4944 | /* already in OOM ? */ | |
79dfdacc | 4945 | if (atomic_read(&memcg->under_oom)) |
9490ff27 | 4946 | eventfd_signal(eventfd, 1); |
1af8efe9 | 4947 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4948 | |
4949 | return 0; | |
4950 | } | |
4951 | ||
907860ed | 4952 | static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp, |
9490ff27 KH |
4953 | struct cftype *cft, struct eventfd_ctx *eventfd) |
4954 | { | |
c0ff4b85 | 4955 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
9490ff27 | 4956 | struct mem_cgroup_eventfd_list *ev, *tmp; |
86ae53e1 | 4957 | enum res_type type = MEMFILE_TYPE(cft->private); |
9490ff27 KH |
4958 | |
4959 | BUG_ON(type != _OOM_TYPE); | |
4960 | ||
1af8efe9 | 4961 | spin_lock(&memcg_oom_lock); |
9490ff27 | 4962 | |
c0ff4b85 | 4963 | list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) { |
9490ff27 KH |
4964 | if (ev->eventfd == eventfd) { |
4965 | list_del(&ev->list); | |
4966 | kfree(ev); | |
4967 | } | |
4968 | } | |
4969 | ||
1af8efe9 | 4970 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4971 | } |
4972 | ||
3c11ecf4 KH |
4973 | static int mem_cgroup_oom_control_read(struct cgroup *cgrp, |
4974 | struct cftype *cft, struct cgroup_map_cb *cb) | |
4975 | { | |
c0ff4b85 | 4976 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
3c11ecf4 | 4977 | |
c0ff4b85 | 4978 | cb->fill(cb, "oom_kill_disable", memcg->oom_kill_disable); |
3c11ecf4 | 4979 | |
c0ff4b85 | 4980 | if (atomic_read(&memcg->under_oom)) |
3c11ecf4 KH |
4981 | cb->fill(cb, "under_oom", 1); |
4982 | else | |
4983 | cb->fill(cb, "under_oom", 0); | |
4984 | return 0; | |
4985 | } | |
4986 | ||
3c11ecf4 KH |
4987 | static int mem_cgroup_oom_control_write(struct cgroup *cgrp, |
4988 | struct cftype *cft, u64 val) | |
4989 | { | |
c0ff4b85 | 4990 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
3c11ecf4 KH |
4991 | struct mem_cgroup *parent; |
4992 | ||
4993 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
4994 | if (!cgrp->parent || !((val == 0) || (val == 1))) | |
4995 | return -EINVAL; | |
4996 | ||
4997 | parent = mem_cgroup_from_cont(cgrp->parent); | |
4998 | ||
4999 | cgroup_lock(); | |
5000 | /* oom-kill-disable is a flag for subhierarchy. */ | |
5001 | if ((parent->use_hierarchy) || | |
c0ff4b85 | 5002 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
3c11ecf4 KH |
5003 | cgroup_unlock(); |
5004 | return -EINVAL; | |
5005 | } | |
c0ff4b85 | 5006 | memcg->oom_kill_disable = val; |
4d845ebf | 5007 | if (!val) |
c0ff4b85 | 5008 | memcg_oom_recover(memcg); |
3c11ecf4 KH |
5009 | cgroup_unlock(); |
5010 | return 0; | |
5011 | } | |
5012 | ||
c255a458 | 5013 | #ifdef CONFIG_MEMCG_KMEM |
cbe128e3 | 5014 | static int memcg_init_kmem(struct mem_cgroup *memcg, struct cgroup_subsys *ss) |
e5671dfa | 5015 | { |
510fc4e1 | 5016 | memcg_propagate_kmem(memcg); |
1d62e436 | 5017 | return mem_cgroup_sockets_init(memcg, ss); |
e5671dfa GC |
5018 | }; |
5019 | ||
1d62e436 | 5020 | static void kmem_cgroup_destroy(struct mem_cgroup *memcg) |
d1a4c0b3 | 5021 | { |
1d62e436 | 5022 | mem_cgroup_sockets_destroy(memcg); |
7de37682 GC |
5023 | |
5024 | memcg_kmem_mark_dead(memcg); | |
5025 | ||
5026 | if (res_counter_read_u64(&memcg->kmem, RES_USAGE) != 0) | |
5027 | return; | |
5028 | ||
5029 | /* | |
5030 | * Charges already down to 0, undo mem_cgroup_get() done in the charge | |
5031 | * path here, being careful not to race with memcg_uncharge_kmem: it is | |
5032 | * possible that the charges went down to 0 between mark_dead and the | |
5033 | * res_counter read, so in that case, we don't need the put | |
5034 | */ | |
5035 | if (memcg_kmem_test_and_clear_dead(memcg)) | |
5036 | mem_cgroup_put(memcg); | |
d1a4c0b3 | 5037 | } |
e5671dfa | 5038 | #else |
cbe128e3 | 5039 | static int memcg_init_kmem(struct mem_cgroup *memcg, struct cgroup_subsys *ss) |
e5671dfa GC |
5040 | { |
5041 | return 0; | |
5042 | } | |
d1a4c0b3 | 5043 | |
1d62e436 | 5044 | static void kmem_cgroup_destroy(struct mem_cgroup *memcg) |
d1a4c0b3 GC |
5045 | { |
5046 | } | |
e5671dfa GC |
5047 | #endif |
5048 | ||
8cdea7c0 BS |
5049 | static struct cftype mem_cgroup_files[] = { |
5050 | { | |
0eea1030 | 5051 | .name = "usage_in_bytes", |
8c7c6e34 | 5052 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
af36f906 | 5053 | .read = mem_cgroup_read, |
9490ff27 KH |
5054 | .register_event = mem_cgroup_usage_register_event, |
5055 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8cdea7c0 | 5056 | }, |
c84872e1 PE |
5057 | { |
5058 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 5059 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
29f2a4da | 5060 | .trigger = mem_cgroup_reset, |
af36f906 | 5061 | .read = mem_cgroup_read, |
c84872e1 | 5062 | }, |
8cdea7c0 | 5063 | { |
0eea1030 | 5064 | .name = "limit_in_bytes", |
8c7c6e34 | 5065 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
856c13aa | 5066 | .write_string = mem_cgroup_write, |
af36f906 | 5067 | .read = mem_cgroup_read, |
8cdea7c0 | 5068 | }, |
296c81d8 BS |
5069 | { |
5070 | .name = "soft_limit_in_bytes", | |
5071 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
5072 | .write_string = mem_cgroup_write, | |
af36f906 | 5073 | .read = mem_cgroup_read, |
296c81d8 | 5074 | }, |
8cdea7c0 BS |
5075 | { |
5076 | .name = "failcnt", | |
8c7c6e34 | 5077 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
29f2a4da | 5078 | .trigger = mem_cgroup_reset, |
af36f906 | 5079 | .read = mem_cgroup_read, |
8cdea7c0 | 5080 | }, |
d2ceb9b7 KH |
5081 | { |
5082 | .name = "stat", | |
ab215884 | 5083 | .read_seq_string = memcg_stat_show, |
d2ceb9b7 | 5084 | }, |
c1e862c1 KH |
5085 | { |
5086 | .name = "force_empty", | |
5087 | .trigger = mem_cgroup_force_empty_write, | |
5088 | }, | |
18f59ea7 BS |
5089 | { |
5090 | .name = "use_hierarchy", | |
5091 | .write_u64 = mem_cgroup_hierarchy_write, | |
5092 | .read_u64 = mem_cgroup_hierarchy_read, | |
5093 | }, | |
a7885eb8 KM |
5094 | { |
5095 | .name = "swappiness", | |
5096 | .read_u64 = mem_cgroup_swappiness_read, | |
5097 | .write_u64 = mem_cgroup_swappiness_write, | |
5098 | }, | |
7dc74be0 DN |
5099 | { |
5100 | .name = "move_charge_at_immigrate", | |
5101 | .read_u64 = mem_cgroup_move_charge_read, | |
5102 | .write_u64 = mem_cgroup_move_charge_write, | |
5103 | }, | |
9490ff27 KH |
5104 | { |
5105 | .name = "oom_control", | |
3c11ecf4 KH |
5106 | .read_map = mem_cgroup_oom_control_read, |
5107 | .write_u64 = mem_cgroup_oom_control_write, | |
9490ff27 KH |
5108 | .register_event = mem_cgroup_oom_register_event, |
5109 | .unregister_event = mem_cgroup_oom_unregister_event, | |
5110 | .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), | |
5111 | }, | |
406eb0c9 YH |
5112 | #ifdef CONFIG_NUMA |
5113 | { | |
5114 | .name = "numa_stat", | |
ab215884 | 5115 | .read_seq_string = memcg_numa_stat_show, |
406eb0c9 YH |
5116 | }, |
5117 | #endif | |
c255a458 | 5118 | #ifdef CONFIG_MEMCG_SWAP |
8c7c6e34 KH |
5119 | { |
5120 | .name = "memsw.usage_in_bytes", | |
5121 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
af36f906 | 5122 | .read = mem_cgroup_read, |
9490ff27 KH |
5123 | .register_event = mem_cgroup_usage_register_event, |
5124 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8c7c6e34 KH |
5125 | }, |
5126 | { | |
5127 | .name = "memsw.max_usage_in_bytes", | |
5128 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
5129 | .trigger = mem_cgroup_reset, | |
af36f906 | 5130 | .read = mem_cgroup_read, |
8c7c6e34 KH |
5131 | }, |
5132 | { | |
5133 | .name = "memsw.limit_in_bytes", | |
5134 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
5135 | .write_string = mem_cgroup_write, | |
af36f906 | 5136 | .read = mem_cgroup_read, |
8c7c6e34 KH |
5137 | }, |
5138 | { | |
5139 | .name = "memsw.failcnt", | |
5140 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
5141 | .trigger = mem_cgroup_reset, | |
af36f906 | 5142 | .read = mem_cgroup_read, |
8c7c6e34 | 5143 | }, |
510fc4e1 GC |
5144 | #endif |
5145 | #ifdef CONFIG_MEMCG_KMEM | |
5146 | { | |
5147 | .name = "kmem.limit_in_bytes", | |
5148 | .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT), | |
5149 | .write_string = mem_cgroup_write, | |
5150 | .read = mem_cgroup_read, | |
5151 | }, | |
5152 | { | |
5153 | .name = "kmem.usage_in_bytes", | |
5154 | .private = MEMFILE_PRIVATE(_KMEM, RES_USAGE), | |
5155 | .read = mem_cgroup_read, | |
5156 | }, | |
5157 | { | |
5158 | .name = "kmem.failcnt", | |
5159 | .private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT), | |
5160 | .trigger = mem_cgroup_reset, | |
5161 | .read = mem_cgroup_read, | |
5162 | }, | |
5163 | { | |
5164 | .name = "kmem.max_usage_in_bytes", | |
5165 | .private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE), | |
5166 | .trigger = mem_cgroup_reset, | |
5167 | .read = mem_cgroup_read, | |
5168 | }, | |
8c7c6e34 | 5169 | #endif |
6bc10349 | 5170 | { }, /* terminate */ |
af36f906 | 5171 | }; |
8c7c6e34 | 5172 | |
c0ff4b85 | 5173 | static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) |
6d12e2d8 KH |
5174 | { |
5175 | struct mem_cgroup_per_node *pn; | |
1ecaab2b | 5176 | struct mem_cgroup_per_zone *mz; |
41e3355d | 5177 | int zone, tmp = node; |
1ecaab2b KH |
5178 | /* |
5179 | * This routine is called against possible nodes. | |
5180 | * But it's BUG to call kmalloc() against offline node. | |
5181 | * | |
5182 | * TODO: this routine can waste much memory for nodes which will | |
5183 | * never be onlined. It's better to use memory hotplug callback | |
5184 | * function. | |
5185 | */ | |
41e3355d KH |
5186 | if (!node_state(node, N_NORMAL_MEMORY)) |
5187 | tmp = -1; | |
17295c88 | 5188 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); |
6d12e2d8 KH |
5189 | if (!pn) |
5190 | return 1; | |
1ecaab2b | 5191 | |
1ecaab2b KH |
5192 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
5193 | mz = &pn->zoneinfo[zone]; | |
bea8c150 | 5194 | lruvec_init(&mz->lruvec); |
f64c3f54 | 5195 | mz->usage_in_excess = 0; |
4e416953 | 5196 | mz->on_tree = false; |
d79154bb | 5197 | mz->memcg = memcg; |
1ecaab2b | 5198 | } |
0a619e58 | 5199 | memcg->info.nodeinfo[node] = pn; |
6d12e2d8 KH |
5200 | return 0; |
5201 | } | |
5202 | ||
c0ff4b85 | 5203 | static void free_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) |
1ecaab2b | 5204 | { |
c0ff4b85 | 5205 | kfree(memcg->info.nodeinfo[node]); |
1ecaab2b KH |
5206 | } |
5207 | ||
33327948 KH |
5208 | static struct mem_cgroup *mem_cgroup_alloc(void) |
5209 | { | |
d79154bb | 5210 | struct mem_cgroup *memcg; |
c62b1a3b | 5211 | int size = sizeof(struct mem_cgroup); |
33327948 | 5212 | |
c62b1a3b | 5213 | /* Can be very big if MAX_NUMNODES is very big */ |
c8dad2bb | 5214 | if (size < PAGE_SIZE) |
d79154bb | 5215 | memcg = kzalloc(size, GFP_KERNEL); |
33327948 | 5216 | else |
d79154bb | 5217 | memcg = vzalloc(size); |
33327948 | 5218 | |
d79154bb | 5219 | if (!memcg) |
e7bbcdf3 DC |
5220 | return NULL; |
5221 | ||
d79154bb HD |
5222 | memcg->stat = alloc_percpu(struct mem_cgroup_stat_cpu); |
5223 | if (!memcg->stat) | |
d2e61b8d | 5224 | goto out_free; |
d79154bb HD |
5225 | spin_lock_init(&memcg->pcp_counter_lock); |
5226 | return memcg; | |
d2e61b8d DC |
5227 | |
5228 | out_free: | |
5229 | if (size < PAGE_SIZE) | |
d79154bb | 5230 | kfree(memcg); |
d2e61b8d | 5231 | else |
d79154bb | 5232 | vfree(memcg); |
d2e61b8d | 5233 | return NULL; |
33327948 KH |
5234 | } |
5235 | ||
59927fb9 | 5236 | /* |
3afe36b1 | 5237 | * Helpers for freeing a kmalloc()ed/vzalloc()ed mem_cgroup by RCU, |
59927fb9 HD |
5238 | * but in process context. The work_freeing structure is overlaid |
5239 | * on the rcu_freeing structure, which itself is overlaid on memsw. | |
5240 | */ | |
3afe36b1 | 5241 | static void free_work(struct work_struct *work) |
59927fb9 HD |
5242 | { |
5243 | struct mem_cgroup *memcg; | |
3afe36b1 | 5244 | int size = sizeof(struct mem_cgroup); |
59927fb9 HD |
5245 | |
5246 | memcg = container_of(work, struct mem_cgroup, work_freeing); | |
3f134619 GC |
5247 | /* |
5248 | * We need to make sure that (at least for now), the jump label | |
5249 | * destruction code runs outside of the cgroup lock. This is because | |
5250 | * get_online_cpus(), which is called from the static_branch update, | |
5251 | * can't be called inside the cgroup_lock. cpusets are the ones | |
5252 | * enforcing this dependency, so if they ever change, we might as well. | |
5253 | * | |
5254 | * schedule_work() will guarantee this happens. Be careful if you need | |
5255 | * to move this code around, and make sure it is outside | |
5256 | * the cgroup_lock. | |
5257 | */ | |
a8964b9b | 5258 | disarm_static_keys(memcg); |
3afe36b1 GC |
5259 | if (size < PAGE_SIZE) |
5260 | kfree(memcg); | |
5261 | else | |
5262 | vfree(memcg); | |
59927fb9 | 5263 | } |
3afe36b1 GC |
5264 | |
5265 | static void free_rcu(struct rcu_head *rcu_head) | |
59927fb9 HD |
5266 | { |
5267 | struct mem_cgroup *memcg; | |
5268 | ||
5269 | memcg = container_of(rcu_head, struct mem_cgroup, rcu_freeing); | |
3afe36b1 | 5270 | INIT_WORK(&memcg->work_freeing, free_work); |
59927fb9 HD |
5271 | schedule_work(&memcg->work_freeing); |
5272 | } | |
5273 | ||
8c7c6e34 KH |
5274 | /* |
5275 | * At destroying mem_cgroup, references from swap_cgroup can remain. | |
5276 | * (scanning all at force_empty is too costly...) | |
5277 | * | |
5278 | * Instead of clearing all references at force_empty, we remember | |
5279 | * the number of reference from swap_cgroup and free mem_cgroup when | |
5280 | * it goes down to 0. | |
5281 | * | |
8c7c6e34 KH |
5282 | * Removal of cgroup itself succeeds regardless of refs from swap. |
5283 | */ | |
5284 | ||
c0ff4b85 | 5285 | static void __mem_cgroup_free(struct mem_cgroup *memcg) |
33327948 | 5286 | { |
08e552c6 KH |
5287 | int node; |
5288 | ||
c0ff4b85 R |
5289 | mem_cgroup_remove_from_trees(memcg); |
5290 | free_css_id(&mem_cgroup_subsys, &memcg->css); | |
04046e1a | 5291 | |
3ed28fa1 | 5292 | for_each_node(node) |
c0ff4b85 | 5293 | free_mem_cgroup_per_zone_info(memcg, node); |
08e552c6 | 5294 | |
c0ff4b85 | 5295 | free_percpu(memcg->stat); |
3afe36b1 | 5296 | call_rcu(&memcg->rcu_freeing, free_rcu); |
33327948 KH |
5297 | } |
5298 | ||
c0ff4b85 | 5299 | static void mem_cgroup_get(struct mem_cgroup *memcg) |
8c7c6e34 | 5300 | { |
c0ff4b85 | 5301 | atomic_inc(&memcg->refcnt); |
8c7c6e34 KH |
5302 | } |
5303 | ||
c0ff4b85 | 5304 | static void __mem_cgroup_put(struct mem_cgroup *memcg, int count) |
8c7c6e34 | 5305 | { |
c0ff4b85 R |
5306 | if (atomic_sub_and_test(count, &memcg->refcnt)) { |
5307 | struct mem_cgroup *parent = parent_mem_cgroup(memcg); | |
5308 | __mem_cgroup_free(memcg); | |
7bcc1bb1 DN |
5309 | if (parent) |
5310 | mem_cgroup_put(parent); | |
5311 | } | |
8c7c6e34 KH |
5312 | } |
5313 | ||
c0ff4b85 | 5314 | static void mem_cgroup_put(struct mem_cgroup *memcg) |
483c30b5 | 5315 | { |
c0ff4b85 | 5316 | __mem_cgroup_put(memcg, 1); |
483c30b5 DN |
5317 | } |
5318 | ||
7bcc1bb1 DN |
5319 | /* |
5320 | * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. | |
5321 | */ | |
e1aab161 | 5322 | struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) |
7bcc1bb1 | 5323 | { |
c0ff4b85 | 5324 | if (!memcg->res.parent) |
7bcc1bb1 | 5325 | return NULL; |
c0ff4b85 | 5326 | return mem_cgroup_from_res_counter(memcg->res.parent, res); |
7bcc1bb1 | 5327 | } |
e1aab161 | 5328 | EXPORT_SYMBOL(parent_mem_cgroup); |
33327948 | 5329 | |
c255a458 | 5330 | #ifdef CONFIG_MEMCG_SWAP |
c077719b KH |
5331 | static void __init enable_swap_cgroup(void) |
5332 | { | |
f8d66542 | 5333 | if (!mem_cgroup_disabled() && really_do_swap_account) |
c077719b KH |
5334 | do_swap_account = 1; |
5335 | } | |
5336 | #else | |
5337 | static void __init enable_swap_cgroup(void) | |
5338 | { | |
5339 | } | |
5340 | #endif | |
5341 | ||
f64c3f54 BS |
5342 | static int mem_cgroup_soft_limit_tree_init(void) |
5343 | { | |
5344 | struct mem_cgroup_tree_per_node *rtpn; | |
5345 | struct mem_cgroup_tree_per_zone *rtpz; | |
5346 | int tmp, node, zone; | |
5347 | ||
3ed28fa1 | 5348 | for_each_node(node) { |
f64c3f54 BS |
5349 | tmp = node; |
5350 | if (!node_state(node, N_NORMAL_MEMORY)) | |
5351 | tmp = -1; | |
5352 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, tmp); | |
5353 | if (!rtpn) | |
c3cecc68 | 5354 | goto err_cleanup; |
f64c3f54 BS |
5355 | |
5356 | soft_limit_tree.rb_tree_per_node[node] = rtpn; | |
5357 | ||
5358 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
5359 | rtpz = &rtpn->rb_tree_per_zone[zone]; | |
5360 | rtpz->rb_root = RB_ROOT; | |
5361 | spin_lock_init(&rtpz->lock); | |
5362 | } | |
5363 | } | |
5364 | return 0; | |
c3cecc68 MH |
5365 | |
5366 | err_cleanup: | |
3ed28fa1 | 5367 | for_each_node(node) { |
c3cecc68 MH |
5368 | if (!soft_limit_tree.rb_tree_per_node[node]) |
5369 | break; | |
5370 | kfree(soft_limit_tree.rb_tree_per_node[node]); | |
5371 | soft_limit_tree.rb_tree_per_node[node] = NULL; | |
5372 | } | |
5373 | return 1; | |
5374 | ||
f64c3f54 BS |
5375 | } |
5376 | ||
0eb253e2 | 5377 | static struct cgroup_subsys_state * __ref |
92fb9748 | 5378 | mem_cgroup_css_alloc(struct cgroup *cont) |
8cdea7c0 | 5379 | { |
c0ff4b85 | 5380 | struct mem_cgroup *memcg, *parent; |
04046e1a | 5381 | long error = -ENOMEM; |
6d12e2d8 | 5382 | int node; |
8cdea7c0 | 5383 | |
c0ff4b85 R |
5384 | memcg = mem_cgroup_alloc(); |
5385 | if (!memcg) | |
04046e1a | 5386 | return ERR_PTR(error); |
78fb7466 | 5387 | |
3ed28fa1 | 5388 | for_each_node(node) |
c0ff4b85 | 5389 | if (alloc_mem_cgroup_per_zone_info(memcg, node)) |
6d12e2d8 | 5390 | goto free_out; |
f64c3f54 | 5391 | |
c077719b | 5392 | /* root ? */ |
28dbc4b6 | 5393 | if (cont->parent == NULL) { |
cdec2e42 | 5394 | int cpu; |
c077719b | 5395 | enable_swap_cgroup(); |
28dbc4b6 | 5396 | parent = NULL; |
f64c3f54 BS |
5397 | if (mem_cgroup_soft_limit_tree_init()) |
5398 | goto free_out; | |
a41c58a6 | 5399 | root_mem_cgroup = memcg; |
cdec2e42 KH |
5400 | for_each_possible_cpu(cpu) { |
5401 | struct memcg_stock_pcp *stock = | |
5402 | &per_cpu(memcg_stock, cpu); | |
5403 | INIT_WORK(&stock->work, drain_local_stock); | |
5404 | } | |
711d3d2c | 5405 | hotcpu_notifier(memcg_cpu_hotplug_callback, 0); |
18f59ea7 | 5406 | } else { |
28dbc4b6 | 5407 | parent = mem_cgroup_from_cont(cont->parent); |
c0ff4b85 R |
5408 | memcg->use_hierarchy = parent->use_hierarchy; |
5409 | memcg->oom_kill_disable = parent->oom_kill_disable; | |
18f59ea7 | 5410 | } |
28dbc4b6 | 5411 | |
18f59ea7 | 5412 | if (parent && parent->use_hierarchy) { |
c0ff4b85 R |
5413 | res_counter_init(&memcg->res, &parent->res); |
5414 | res_counter_init(&memcg->memsw, &parent->memsw); | |
510fc4e1 | 5415 | res_counter_init(&memcg->kmem, &parent->kmem); |
7bcc1bb1 DN |
5416 | /* |
5417 | * We increment refcnt of the parent to ensure that we can | |
5418 | * safely access it on res_counter_charge/uncharge. | |
5419 | * This refcnt will be decremented when freeing this | |
5420 | * mem_cgroup(see mem_cgroup_put). | |
5421 | */ | |
5422 | mem_cgroup_get(parent); | |
18f59ea7 | 5423 | } else { |
c0ff4b85 R |
5424 | res_counter_init(&memcg->res, NULL); |
5425 | res_counter_init(&memcg->memsw, NULL); | |
510fc4e1 | 5426 | res_counter_init(&memcg->kmem, NULL); |
8c7f6edb TH |
5427 | /* |
5428 | * Deeper hierachy with use_hierarchy == false doesn't make | |
5429 | * much sense so let cgroup subsystem know about this | |
5430 | * unfortunate state in our controller. | |
5431 | */ | |
5432 | if (parent && parent != root_mem_cgroup) | |
5433 | mem_cgroup_subsys.broken_hierarchy = true; | |
18f59ea7 | 5434 | } |
c0ff4b85 R |
5435 | memcg->last_scanned_node = MAX_NUMNODES; |
5436 | INIT_LIST_HEAD(&memcg->oom_notify); | |
6d61ef40 | 5437 | |
a7885eb8 | 5438 | if (parent) |
c0ff4b85 R |
5439 | memcg->swappiness = mem_cgroup_swappiness(parent); |
5440 | atomic_set(&memcg->refcnt, 1); | |
5441 | memcg->move_charge_at_immigrate = 0; | |
5442 | mutex_init(&memcg->thresholds_lock); | |
312734c0 | 5443 | spin_lock_init(&memcg->move_lock); |
cbe128e3 GC |
5444 | |
5445 | error = memcg_init_kmem(memcg, &mem_cgroup_subsys); | |
5446 | if (error) { | |
5447 | /* | |
5448 | * We call put now because our (and parent's) refcnts | |
5449 | * are already in place. mem_cgroup_put() will internally | |
5450 | * call __mem_cgroup_free, so return directly | |
5451 | */ | |
5452 | mem_cgroup_put(memcg); | |
5453 | return ERR_PTR(error); | |
5454 | } | |
c0ff4b85 | 5455 | return &memcg->css; |
6d12e2d8 | 5456 | free_out: |
c0ff4b85 | 5457 | __mem_cgroup_free(memcg); |
04046e1a | 5458 | return ERR_PTR(error); |
8cdea7c0 BS |
5459 | } |
5460 | ||
92fb9748 | 5461 | static void mem_cgroup_css_offline(struct cgroup *cont) |
df878fb0 | 5462 | { |
c0ff4b85 | 5463 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
ec64f515 | 5464 | |
ab5196c2 | 5465 | mem_cgroup_reparent_charges(memcg); |
df878fb0 KH |
5466 | } |
5467 | ||
92fb9748 | 5468 | static void mem_cgroup_css_free(struct cgroup *cont) |
8cdea7c0 | 5469 | { |
c0ff4b85 | 5470 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
c268e994 | 5471 | |
1d62e436 | 5472 | kmem_cgroup_destroy(memcg); |
d1a4c0b3 | 5473 | |
c0ff4b85 | 5474 | mem_cgroup_put(memcg); |
8cdea7c0 BS |
5475 | } |
5476 | ||
02491447 | 5477 | #ifdef CONFIG_MMU |
7dc74be0 | 5478 | /* Handlers for move charge at task migration. */ |
854ffa8d DN |
5479 | #define PRECHARGE_COUNT_AT_ONCE 256 |
5480 | static int mem_cgroup_do_precharge(unsigned long count) | |
7dc74be0 | 5481 | { |
854ffa8d DN |
5482 | int ret = 0; |
5483 | int batch_count = PRECHARGE_COUNT_AT_ONCE; | |
c0ff4b85 | 5484 | struct mem_cgroup *memcg = mc.to; |
4ffef5fe | 5485 | |
c0ff4b85 | 5486 | if (mem_cgroup_is_root(memcg)) { |
854ffa8d DN |
5487 | mc.precharge += count; |
5488 | /* we don't need css_get for root */ | |
5489 | return ret; | |
5490 | } | |
5491 | /* try to charge at once */ | |
5492 | if (count > 1) { | |
5493 | struct res_counter *dummy; | |
5494 | /* | |
c0ff4b85 | 5495 | * "memcg" cannot be under rmdir() because we've already checked |
854ffa8d DN |
5496 | * by cgroup_lock_live_cgroup() that it is not removed and we |
5497 | * are still under the same cgroup_mutex. So we can postpone | |
5498 | * css_get(). | |
5499 | */ | |
c0ff4b85 | 5500 | if (res_counter_charge(&memcg->res, PAGE_SIZE * count, &dummy)) |
854ffa8d | 5501 | goto one_by_one; |
c0ff4b85 | 5502 | if (do_swap_account && res_counter_charge(&memcg->memsw, |
854ffa8d | 5503 | PAGE_SIZE * count, &dummy)) { |
c0ff4b85 | 5504 | res_counter_uncharge(&memcg->res, PAGE_SIZE * count); |
854ffa8d DN |
5505 | goto one_by_one; |
5506 | } | |
5507 | mc.precharge += count; | |
854ffa8d DN |
5508 | return ret; |
5509 | } | |
5510 | one_by_one: | |
5511 | /* fall back to one by one charge */ | |
5512 | while (count--) { | |
5513 | if (signal_pending(current)) { | |
5514 | ret = -EINTR; | |
5515 | break; | |
5516 | } | |
5517 | if (!batch_count--) { | |
5518 | batch_count = PRECHARGE_COUNT_AT_ONCE; | |
5519 | cond_resched(); | |
5520 | } | |
c0ff4b85 R |
5521 | ret = __mem_cgroup_try_charge(NULL, |
5522 | GFP_KERNEL, 1, &memcg, false); | |
38c5d72f | 5523 | if (ret) |
854ffa8d | 5524 | /* mem_cgroup_clear_mc() will do uncharge later */ |
38c5d72f | 5525 | return ret; |
854ffa8d DN |
5526 | mc.precharge++; |
5527 | } | |
4ffef5fe DN |
5528 | return ret; |
5529 | } | |
5530 | ||
5531 | /** | |
8d32ff84 | 5532 | * get_mctgt_type - get target type of moving charge |
4ffef5fe DN |
5533 | * @vma: the vma the pte to be checked belongs |
5534 | * @addr: the address corresponding to the pte to be checked | |
5535 | * @ptent: the pte to be checked | |
02491447 | 5536 | * @target: the pointer the target page or swap ent will be stored(can be NULL) |
4ffef5fe DN |
5537 | * |
5538 | * Returns | |
5539 | * 0(MC_TARGET_NONE): if the pte is not a target for move charge. | |
5540 | * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for | |
5541 | * move charge. if @target is not NULL, the page is stored in target->page | |
5542 | * with extra refcnt got(Callers should handle it). | |
02491447 DN |
5543 | * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a |
5544 | * target for charge migration. if @target is not NULL, the entry is stored | |
5545 | * in target->ent. | |
4ffef5fe DN |
5546 | * |
5547 | * Called with pte lock held. | |
5548 | */ | |
4ffef5fe DN |
5549 | union mc_target { |
5550 | struct page *page; | |
02491447 | 5551 | swp_entry_t ent; |
4ffef5fe DN |
5552 | }; |
5553 | ||
4ffef5fe | 5554 | enum mc_target_type { |
8d32ff84 | 5555 | MC_TARGET_NONE = 0, |
4ffef5fe | 5556 | MC_TARGET_PAGE, |
02491447 | 5557 | MC_TARGET_SWAP, |
4ffef5fe DN |
5558 | }; |
5559 | ||
90254a65 DN |
5560 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
5561 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 5562 | { |
90254a65 | 5563 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 5564 | |
90254a65 DN |
5565 | if (!page || !page_mapped(page)) |
5566 | return NULL; | |
5567 | if (PageAnon(page)) { | |
5568 | /* we don't move shared anon */ | |
4b91355e | 5569 | if (!move_anon()) |
90254a65 | 5570 | return NULL; |
87946a72 DN |
5571 | } else if (!move_file()) |
5572 | /* we ignore mapcount for file pages */ | |
90254a65 DN |
5573 | return NULL; |
5574 | if (!get_page_unless_zero(page)) | |
5575 | return NULL; | |
5576 | ||
5577 | return page; | |
5578 | } | |
5579 | ||
4b91355e | 5580 | #ifdef CONFIG_SWAP |
90254a65 DN |
5581 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, |
5582 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5583 | { | |
90254a65 DN |
5584 | struct page *page = NULL; |
5585 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
5586 | ||
5587 | if (!move_anon() || non_swap_entry(ent)) | |
5588 | return NULL; | |
4b91355e KH |
5589 | /* |
5590 | * Because lookup_swap_cache() updates some statistics counter, | |
5591 | * we call find_get_page() with swapper_space directly. | |
5592 | */ | |
5593 | page = find_get_page(&swapper_space, ent.val); | |
90254a65 DN |
5594 | if (do_swap_account) |
5595 | entry->val = ent.val; | |
5596 | ||
5597 | return page; | |
5598 | } | |
4b91355e KH |
5599 | #else |
5600 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
5601 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5602 | { | |
5603 | return NULL; | |
5604 | } | |
5605 | #endif | |
90254a65 | 5606 | |
87946a72 DN |
5607 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
5608 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5609 | { | |
5610 | struct page *page = NULL; | |
87946a72 DN |
5611 | struct address_space *mapping; |
5612 | pgoff_t pgoff; | |
5613 | ||
5614 | if (!vma->vm_file) /* anonymous vma */ | |
5615 | return NULL; | |
5616 | if (!move_file()) | |
5617 | return NULL; | |
5618 | ||
87946a72 DN |
5619 | mapping = vma->vm_file->f_mapping; |
5620 | if (pte_none(ptent)) | |
5621 | pgoff = linear_page_index(vma, addr); | |
5622 | else /* pte_file(ptent) is true */ | |
5623 | pgoff = pte_to_pgoff(ptent); | |
5624 | ||
5625 | /* page is moved even if it's not RSS of this task(page-faulted). */ | |
aa3b1895 HD |
5626 | page = find_get_page(mapping, pgoff); |
5627 | ||
5628 | #ifdef CONFIG_SWAP | |
5629 | /* shmem/tmpfs may report page out on swap: account for that too. */ | |
5630 | if (radix_tree_exceptional_entry(page)) { | |
5631 | swp_entry_t swap = radix_to_swp_entry(page); | |
87946a72 | 5632 | if (do_swap_account) |
aa3b1895 HD |
5633 | *entry = swap; |
5634 | page = find_get_page(&swapper_space, swap.val); | |
87946a72 | 5635 | } |
aa3b1895 | 5636 | #endif |
87946a72 DN |
5637 | return page; |
5638 | } | |
5639 | ||
8d32ff84 | 5640 | static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, |
90254a65 DN |
5641 | unsigned long addr, pte_t ptent, union mc_target *target) |
5642 | { | |
5643 | struct page *page = NULL; | |
5644 | struct page_cgroup *pc; | |
8d32ff84 | 5645 | enum mc_target_type ret = MC_TARGET_NONE; |
90254a65 DN |
5646 | swp_entry_t ent = { .val = 0 }; |
5647 | ||
5648 | if (pte_present(ptent)) | |
5649 | page = mc_handle_present_pte(vma, addr, ptent); | |
5650 | else if (is_swap_pte(ptent)) | |
5651 | page = mc_handle_swap_pte(vma, addr, ptent, &ent); | |
87946a72 DN |
5652 | else if (pte_none(ptent) || pte_file(ptent)) |
5653 | page = mc_handle_file_pte(vma, addr, ptent, &ent); | |
90254a65 DN |
5654 | |
5655 | if (!page && !ent.val) | |
8d32ff84 | 5656 | return ret; |
02491447 DN |
5657 | if (page) { |
5658 | pc = lookup_page_cgroup(page); | |
5659 | /* | |
5660 | * Do only loose check w/o page_cgroup lock. | |
5661 | * mem_cgroup_move_account() checks the pc is valid or not under | |
5662 | * the lock. | |
5663 | */ | |
5664 | if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { | |
5665 | ret = MC_TARGET_PAGE; | |
5666 | if (target) | |
5667 | target->page = page; | |
5668 | } | |
5669 | if (!ret || !target) | |
5670 | put_page(page); | |
5671 | } | |
90254a65 DN |
5672 | /* There is a swap entry and a page doesn't exist or isn't charged */ |
5673 | if (ent.val && !ret && | |
9fb4b7cc | 5674 | css_id(&mc.from->css) == lookup_swap_cgroup_id(ent)) { |
7f0f1546 KH |
5675 | ret = MC_TARGET_SWAP; |
5676 | if (target) | |
5677 | target->ent = ent; | |
4ffef5fe | 5678 | } |
4ffef5fe DN |
5679 | return ret; |
5680 | } | |
5681 | ||
12724850 NH |
5682 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
5683 | /* | |
5684 | * We don't consider swapping or file mapped pages because THP does not | |
5685 | * support them for now. | |
5686 | * Caller should make sure that pmd_trans_huge(pmd) is true. | |
5687 | */ | |
5688 | static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
5689 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
5690 | { | |
5691 | struct page *page = NULL; | |
5692 | struct page_cgroup *pc; | |
5693 | enum mc_target_type ret = MC_TARGET_NONE; | |
5694 | ||
5695 | page = pmd_page(pmd); | |
5696 | VM_BUG_ON(!page || !PageHead(page)); | |
5697 | if (!move_anon()) | |
5698 | return ret; | |
5699 | pc = lookup_page_cgroup(page); | |
5700 | if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { | |
5701 | ret = MC_TARGET_PAGE; | |
5702 | if (target) { | |
5703 | get_page(page); | |
5704 | target->page = page; | |
5705 | } | |
5706 | } | |
5707 | return ret; | |
5708 | } | |
5709 | #else | |
5710 | static inline enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, | |
5711 | unsigned long addr, pmd_t pmd, union mc_target *target) | |
5712 | { | |
5713 | return MC_TARGET_NONE; | |
5714 | } | |
5715 | #endif | |
5716 | ||
4ffef5fe DN |
5717 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, |
5718 | unsigned long addr, unsigned long end, | |
5719 | struct mm_walk *walk) | |
5720 | { | |
5721 | struct vm_area_struct *vma = walk->private; | |
5722 | pte_t *pte; | |
5723 | spinlock_t *ptl; | |
5724 | ||
12724850 NH |
5725 | if (pmd_trans_huge_lock(pmd, vma) == 1) { |
5726 | if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE) | |
5727 | mc.precharge += HPAGE_PMD_NR; | |
5728 | spin_unlock(&vma->vm_mm->page_table_lock); | |
1a5a9906 | 5729 | return 0; |
12724850 | 5730 | } |
03319327 | 5731 | |
45f83cef AA |
5732 | if (pmd_trans_unstable(pmd)) |
5733 | return 0; | |
4ffef5fe DN |
5734 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
5735 | for (; addr != end; pte++, addr += PAGE_SIZE) | |
8d32ff84 | 5736 | if (get_mctgt_type(vma, addr, *pte, NULL)) |
4ffef5fe DN |
5737 | mc.precharge++; /* increment precharge temporarily */ |
5738 | pte_unmap_unlock(pte - 1, ptl); | |
5739 | cond_resched(); | |
5740 | ||
7dc74be0 DN |
5741 | return 0; |
5742 | } | |
5743 | ||
4ffef5fe DN |
5744 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
5745 | { | |
5746 | unsigned long precharge; | |
5747 | struct vm_area_struct *vma; | |
5748 | ||
dfe076b0 | 5749 | down_read(&mm->mmap_sem); |
4ffef5fe DN |
5750 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5751 | struct mm_walk mem_cgroup_count_precharge_walk = { | |
5752 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
5753 | .mm = mm, | |
5754 | .private = vma, | |
5755 | }; | |
5756 | if (is_vm_hugetlb_page(vma)) | |
5757 | continue; | |
4ffef5fe DN |
5758 | walk_page_range(vma->vm_start, vma->vm_end, |
5759 | &mem_cgroup_count_precharge_walk); | |
5760 | } | |
dfe076b0 | 5761 | up_read(&mm->mmap_sem); |
4ffef5fe DN |
5762 | |
5763 | precharge = mc.precharge; | |
5764 | mc.precharge = 0; | |
5765 | ||
5766 | return precharge; | |
5767 | } | |
5768 | ||
4ffef5fe DN |
5769 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
5770 | { | |
dfe076b0 DN |
5771 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
5772 | ||
5773 | VM_BUG_ON(mc.moving_task); | |
5774 | mc.moving_task = current; | |
5775 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
5776 | } |
5777 | ||
dfe076b0 DN |
5778 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
5779 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 5780 | { |
2bd9bb20 KH |
5781 | struct mem_cgroup *from = mc.from; |
5782 | struct mem_cgroup *to = mc.to; | |
5783 | ||
4ffef5fe | 5784 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d DN |
5785 | if (mc.precharge) { |
5786 | __mem_cgroup_cancel_charge(mc.to, mc.precharge); | |
5787 | mc.precharge = 0; | |
5788 | } | |
5789 | /* | |
5790 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
5791 | * we must uncharge here. | |
5792 | */ | |
5793 | if (mc.moved_charge) { | |
5794 | __mem_cgroup_cancel_charge(mc.from, mc.moved_charge); | |
5795 | mc.moved_charge = 0; | |
4ffef5fe | 5796 | } |
483c30b5 DN |
5797 | /* we must fixup refcnts and charges */ |
5798 | if (mc.moved_swap) { | |
483c30b5 DN |
5799 | /* uncharge swap account from the old cgroup */ |
5800 | if (!mem_cgroup_is_root(mc.from)) | |
5801 | res_counter_uncharge(&mc.from->memsw, | |
5802 | PAGE_SIZE * mc.moved_swap); | |
5803 | __mem_cgroup_put(mc.from, mc.moved_swap); | |
5804 | ||
5805 | if (!mem_cgroup_is_root(mc.to)) { | |
5806 | /* | |
5807 | * we charged both to->res and to->memsw, so we should | |
5808 | * uncharge to->res. | |
5809 | */ | |
5810 | res_counter_uncharge(&mc.to->res, | |
5811 | PAGE_SIZE * mc.moved_swap); | |
483c30b5 DN |
5812 | } |
5813 | /* we've already done mem_cgroup_get(mc.to) */ | |
483c30b5 DN |
5814 | mc.moved_swap = 0; |
5815 | } | |
dfe076b0 DN |
5816 | memcg_oom_recover(from); |
5817 | memcg_oom_recover(to); | |
5818 | wake_up_all(&mc.waitq); | |
5819 | } | |
5820 | ||
5821 | static void mem_cgroup_clear_mc(void) | |
5822 | { | |
5823 | struct mem_cgroup *from = mc.from; | |
5824 | ||
5825 | /* | |
5826 | * we must clear moving_task before waking up waiters at the end of | |
5827 | * task migration. | |
5828 | */ | |
5829 | mc.moving_task = NULL; | |
5830 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 5831 | spin_lock(&mc.lock); |
4ffef5fe DN |
5832 | mc.from = NULL; |
5833 | mc.to = NULL; | |
2bd9bb20 | 5834 | spin_unlock(&mc.lock); |
32047e2a | 5835 | mem_cgroup_end_move(from); |
4ffef5fe DN |
5836 | } |
5837 | ||
761b3ef5 LZ |
5838 | static int mem_cgroup_can_attach(struct cgroup *cgroup, |
5839 | struct cgroup_taskset *tset) | |
7dc74be0 | 5840 | { |
2f7ee569 | 5841 | struct task_struct *p = cgroup_taskset_first(tset); |
7dc74be0 | 5842 | int ret = 0; |
c0ff4b85 | 5843 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgroup); |
7dc74be0 | 5844 | |
c0ff4b85 | 5845 | if (memcg->move_charge_at_immigrate) { |
7dc74be0 DN |
5846 | struct mm_struct *mm; |
5847 | struct mem_cgroup *from = mem_cgroup_from_task(p); | |
5848 | ||
c0ff4b85 | 5849 | VM_BUG_ON(from == memcg); |
7dc74be0 DN |
5850 | |
5851 | mm = get_task_mm(p); | |
5852 | if (!mm) | |
5853 | return 0; | |
7dc74be0 | 5854 | /* We move charges only when we move a owner of the mm */ |
4ffef5fe DN |
5855 | if (mm->owner == p) { |
5856 | VM_BUG_ON(mc.from); | |
5857 | VM_BUG_ON(mc.to); | |
5858 | VM_BUG_ON(mc.precharge); | |
854ffa8d | 5859 | VM_BUG_ON(mc.moved_charge); |
483c30b5 | 5860 | VM_BUG_ON(mc.moved_swap); |
32047e2a | 5861 | mem_cgroup_start_move(from); |
2bd9bb20 | 5862 | spin_lock(&mc.lock); |
4ffef5fe | 5863 | mc.from = from; |
c0ff4b85 | 5864 | mc.to = memcg; |
2bd9bb20 | 5865 | spin_unlock(&mc.lock); |
dfe076b0 | 5866 | /* We set mc.moving_task later */ |
4ffef5fe DN |
5867 | |
5868 | ret = mem_cgroup_precharge_mc(mm); | |
5869 | if (ret) | |
5870 | mem_cgroup_clear_mc(); | |
dfe076b0 DN |
5871 | } |
5872 | mmput(mm); | |
7dc74be0 DN |
5873 | } |
5874 | return ret; | |
5875 | } | |
5876 | ||
761b3ef5 LZ |
5877 | static void mem_cgroup_cancel_attach(struct cgroup *cgroup, |
5878 | struct cgroup_taskset *tset) | |
7dc74be0 | 5879 | { |
4ffef5fe | 5880 | mem_cgroup_clear_mc(); |
7dc74be0 DN |
5881 | } |
5882 | ||
4ffef5fe DN |
5883 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
5884 | unsigned long addr, unsigned long end, | |
5885 | struct mm_walk *walk) | |
7dc74be0 | 5886 | { |
4ffef5fe DN |
5887 | int ret = 0; |
5888 | struct vm_area_struct *vma = walk->private; | |
5889 | pte_t *pte; | |
5890 | spinlock_t *ptl; | |
12724850 NH |
5891 | enum mc_target_type target_type; |
5892 | union mc_target target; | |
5893 | struct page *page; | |
5894 | struct page_cgroup *pc; | |
4ffef5fe | 5895 | |
12724850 NH |
5896 | /* |
5897 | * We don't take compound_lock() here but no race with splitting thp | |
5898 | * happens because: | |
5899 | * - if pmd_trans_huge_lock() returns 1, the relevant thp is not | |
5900 | * under splitting, which means there's no concurrent thp split, | |
5901 | * - if another thread runs into split_huge_page() just after we | |
5902 | * entered this if-block, the thread must wait for page table lock | |
5903 | * to be unlocked in __split_huge_page_splitting(), where the main | |
5904 | * part of thp split is not executed yet. | |
5905 | */ | |
5906 | if (pmd_trans_huge_lock(pmd, vma) == 1) { | |
62ade86a | 5907 | if (mc.precharge < HPAGE_PMD_NR) { |
12724850 NH |
5908 | spin_unlock(&vma->vm_mm->page_table_lock); |
5909 | return 0; | |
5910 | } | |
5911 | target_type = get_mctgt_type_thp(vma, addr, *pmd, &target); | |
5912 | if (target_type == MC_TARGET_PAGE) { | |
5913 | page = target.page; | |
5914 | if (!isolate_lru_page(page)) { | |
5915 | pc = lookup_page_cgroup(page); | |
5916 | if (!mem_cgroup_move_account(page, HPAGE_PMD_NR, | |
2f3479b1 | 5917 | pc, mc.from, mc.to)) { |
12724850 NH |
5918 | mc.precharge -= HPAGE_PMD_NR; |
5919 | mc.moved_charge += HPAGE_PMD_NR; | |
5920 | } | |
5921 | putback_lru_page(page); | |
5922 | } | |
5923 | put_page(page); | |
5924 | } | |
5925 | spin_unlock(&vma->vm_mm->page_table_lock); | |
1a5a9906 | 5926 | return 0; |
12724850 NH |
5927 | } |
5928 | ||
45f83cef AA |
5929 | if (pmd_trans_unstable(pmd)) |
5930 | return 0; | |
4ffef5fe DN |
5931 | retry: |
5932 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
5933 | for (; addr != end; addr += PAGE_SIZE) { | |
5934 | pte_t ptent = *(pte++); | |
02491447 | 5935 | swp_entry_t ent; |
4ffef5fe DN |
5936 | |
5937 | if (!mc.precharge) | |
5938 | break; | |
5939 | ||
8d32ff84 | 5940 | switch (get_mctgt_type(vma, addr, ptent, &target)) { |
4ffef5fe DN |
5941 | case MC_TARGET_PAGE: |
5942 | page = target.page; | |
5943 | if (isolate_lru_page(page)) | |
5944 | goto put; | |
5945 | pc = lookup_page_cgroup(page); | |
7ec99d62 | 5946 | if (!mem_cgroup_move_account(page, 1, pc, |
2f3479b1 | 5947 | mc.from, mc.to)) { |
4ffef5fe | 5948 | mc.precharge--; |
854ffa8d DN |
5949 | /* we uncharge from mc.from later. */ |
5950 | mc.moved_charge++; | |
4ffef5fe DN |
5951 | } |
5952 | putback_lru_page(page); | |
8d32ff84 | 5953 | put: /* get_mctgt_type() gets the page */ |
4ffef5fe DN |
5954 | put_page(page); |
5955 | break; | |
02491447 DN |
5956 | case MC_TARGET_SWAP: |
5957 | ent = target.ent; | |
e91cbb42 | 5958 | if (!mem_cgroup_move_swap_account(ent, mc.from, mc.to)) { |
02491447 | 5959 | mc.precharge--; |
483c30b5 DN |
5960 | /* we fixup refcnts and charges later. */ |
5961 | mc.moved_swap++; | |
5962 | } | |
02491447 | 5963 | break; |
4ffef5fe DN |
5964 | default: |
5965 | break; | |
5966 | } | |
5967 | } | |
5968 | pte_unmap_unlock(pte - 1, ptl); | |
5969 | cond_resched(); | |
5970 | ||
5971 | if (addr != end) { | |
5972 | /* | |
5973 | * We have consumed all precharges we got in can_attach(). | |
5974 | * We try charge one by one, but don't do any additional | |
5975 | * charges to mc.to if we have failed in charge once in attach() | |
5976 | * phase. | |
5977 | */ | |
854ffa8d | 5978 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
5979 | if (!ret) |
5980 | goto retry; | |
5981 | } | |
5982 | ||
5983 | return ret; | |
5984 | } | |
5985 | ||
5986 | static void mem_cgroup_move_charge(struct mm_struct *mm) | |
5987 | { | |
5988 | struct vm_area_struct *vma; | |
5989 | ||
5990 | lru_add_drain_all(); | |
dfe076b0 DN |
5991 | retry: |
5992 | if (unlikely(!down_read_trylock(&mm->mmap_sem))) { | |
5993 | /* | |
5994 | * Someone who are holding the mmap_sem might be waiting in | |
5995 | * waitq. So we cancel all extra charges, wake up all waiters, | |
5996 | * and retry. Because we cancel precharges, we might not be able | |
5997 | * to move enough charges, but moving charge is a best-effort | |
5998 | * feature anyway, so it wouldn't be a big problem. | |
5999 | */ | |
6000 | __mem_cgroup_clear_mc(); | |
6001 | cond_resched(); | |
6002 | goto retry; | |
6003 | } | |
4ffef5fe DN |
6004 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
6005 | int ret; | |
6006 | struct mm_walk mem_cgroup_move_charge_walk = { | |
6007 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
6008 | .mm = mm, | |
6009 | .private = vma, | |
6010 | }; | |
6011 | if (is_vm_hugetlb_page(vma)) | |
6012 | continue; | |
4ffef5fe DN |
6013 | ret = walk_page_range(vma->vm_start, vma->vm_end, |
6014 | &mem_cgroup_move_charge_walk); | |
6015 | if (ret) | |
6016 | /* | |
6017 | * means we have consumed all precharges and failed in | |
6018 | * doing additional charge. Just abandon here. | |
6019 | */ | |
6020 | break; | |
6021 | } | |
dfe076b0 | 6022 | up_read(&mm->mmap_sem); |
7dc74be0 DN |
6023 | } |
6024 | ||
761b3ef5 LZ |
6025 | static void mem_cgroup_move_task(struct cgroup *cont, |
6026 | struct cgroup_taskset *tset) | |
67e465a7 | 6027 | { |
2f7ee569 | 6028 | struct task_struct *p = cgroup_taskset_first(tset); |
a433658c | 6029 | struct mm_struct *mm = get_task_mm(p); |
dfe076b0 | 6030 | |
dfe076b0 | 6031 | if (mm) { |
a433658c KM |
6032 | if (mc.to) |
6033 | mem_cgroup_move_charge(mm); | |
dfe076b0 DN |
6034 | mmput(mm); |
6035 | } | |
a433658c KM |
6036 | if (mc.to) |
6037 | mem_cgroup_clear_mc(); | |
67e465a7 | 6038 | } |
5cfb80a7 | 6039 | #else /* !CONFIG_MMU */ |
761b3ef5 LZ |
6040 | static int mem_cgroup_can_attach(struct cgroup *cgroup, |
6041 | struct cgroup_taskset *tset) | |
5cfb80a7 DN |
6042 | { |
6043 | return 0; | |
6044 | } | |
761b3ef5 LZ |
6045 | static void mem_cgroup_cancel_attach(struct cgroup *cgroup, |
6046 | struct cgroup_taskset *tset) | |
5cfb80a7 DN |
6047 | { |
6048 | } | |
761b3ef5 LZ |
6049 | static void mem_cgroup_move_task(struct cgroup *cont, |
6050 | struct cgroup_taskset *tset) | |
5cfb80a7 DN |
6051 | { |
6052 | } | |
6053 | #endif | |
67e465a7 | 6054 | |
8cdea7c0 BS |
6055 | struct cgroup_subsys mem_cgroup_subsys = { |
6056 | .name = "memory", | |
6057 | .subsys_id = mem_cgroup_subsys_id, | |
92fb9748 TH |
6058 | .css_alloc = mem_cgroup_css_alloc, |
6059 | .css_offline = mem_cgroup_css_offline, | |
6060 | .css_free = mem_cgroup_css_free, | |
7dc74be0 DN |
6061 | .can_attach = mem_cgroup_can_attach, |
6062 | .cancel_attach = mem_cgroup_cancel_attach, | |
67e465a7 | 6063 | .attach = mem_cgroup_move_task, |
6bc10349 | 6064 | .base_cftypes = mem_cgroup_files, |
6d12e2d8 | 6065 | .early_init = 0, |
04046e1a | 6066 | .use_id = 1, |
8cdea7c0 | 6067 | }; |
c077719b | 6068 | |
c255a458 | 6069 | #ifdef CONFIG_MEMCG_SWAP |
a42c390c MH |
6070 | static int __init enable_swap_account(char *s) |
6071 | { | |
6072 | /* consider enabled if no parameter or 1 is given */ | |
a2c8990a | 6073 | if (!strcmp(s, "1")) |
a42c390c | 6074 | really_do_swap_account = 1; |
a2c8990a | 6075 | else if (!strcmp(s, "0")) |
a42c390c MH |
6076 | really_do_swap_account = 0; |
6077 | return 1; | |
6078 | } | |
a2c8990a | 6079 | __setup("swapaccount=", enable_swap_account); |
c077719b | 6080 | |
c077719b | 6081 | #endif |