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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 | * | |
8cdea7c0 BS |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License as published by | |
15 | * the Free Software Foundation; either version 2 of the License, or | |
16 | * (at your option) any later version. | |
17 | * | |
18 | * This program is distributed in the hope that it will be useful, | |
19 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
21 | * GNU General Public License for more details. | |
22 | */ | |
23 | ||
24 | #include <linux/res_counter.h> | |
25 | #include <linux/memcontrol.h> | |
26 | #include <linux/cgroup.h> | |
78fb7466 | 27 | #include <linux/mm.h> |
4ffef5fe | 28 | #include <linux/hugetlb.h> |
d13d1443 | 29 | #include <linux/pagemap.h> |
d52aa412 | 30 | #include <linux/smp.h> |
8a9f3ccd | 31 | #include <linux/page-flags.h> |
66e1707b | 32 | #include <linux/backing-dev.h> |
8a9f3ccd BS |
33 | #include <linux/bit_spinlock.h> |
34 | #include <linux/rcupdate.h> | |
e222432b | 35 | #include <linux/limits.h> |
b9e15baf | 36 | #include <linux/export.h> |
8c7c6e34 | 37 | #include <linux/mutex.h> |
f64c3f54 | 38 | #include <linux/rbtree.h> |
b6ac57d5 | 39 | #include <linux/slab.h> |
66e1707b | 40 | #include <linux/swap.h> |
02491447 | 41 | #include <linux/swapops.h> |
66e1707b | 42 | #include <linux/spinlock.h> |
2e72b634 KS |
43 | #include <linux/eventfd.h> |
44 | #include <linux/sort.h> | |
66e1707b | 45 | #include <linux/fs.h> |
d2ceb9b7 | 46 | #include <linux/seq_file.h> |
33327948 | 47 | #include <linux/vmalloc.h> |
b69408e8 | 48 | #include <linux/mm_inline.h> |
52d4b9ac | 49 | #include <linux/page_cgroup.h> |
cdec2e42 | 50 | #include <linux/cpu.h> |
158e0a2d | 51 | #include <linux/oom.h> |
08e552c6 | 52 | #include "internal.h" |
d1a4c0b3 GC |
53 | #include <net/sock.h> |
54 | #include <net/tcp_memcontrol.h> | |
8cdea7c0 | 55 | |
8697d331 BS |
56 | #include <asm/uaccess.h> |
57 | ||
cc8e970c KM |
58 | #include <trace/events/vmscan.h> |
59 | ||
a181b0e8 | 60 | struct cgroup_subsys mem_cgroup_subsys __read_mostly; |
a181b0e8 | 61 | #define MEM_CGROUP_RECLAIM_RETRIES 5 |
4b3bde4c | 62 | struct mem_cgroup *root_mem_cgroup __read_mostly; |
8cdea7c0 | 63 | |
c077719b | 64 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
338c8431 | 65 | /* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */ |
c077719b | 66 | int do_swap_account __read_mostly; |
a42c390c MH |
67 | |
68 | /* for remember boot option*/ | |
69 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED | |
70 | static int really_do_swap_account __initdata = 1; | |
71 | #else | |
72 | static int really_do_swap_account __initdata = 0; | |
73 | #endif | |
74 | ||
c077719b KH |
75 | #else |
76 | #define do_swap_account (0) | |
77 | #endif | |
78 | ||
79 | ||
d52aa412 KH |
80 | /* |
81 | * Statistics for memory cgroup. | |
82 | */ | |
83 | enum mem_cgroup_stat_index { | |
84 | /* | |
85 | * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss. | |
86 | */ | |
87 | MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */ | |
d69b042f | 88 | MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */ |
d8046582 | 89 | MEM_CGROUP_STAT_FILE_MAPPED, /* # of pages charged as file rss */ |
0c3e73e8 | 90 | MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */ |
711d3d2c | 91 | MEM_CGROUP_STAT_DATA, /* end of data requires synchronization */ |
32047e2a | 92 | MEM_CGROUP_ON_MOVE, /* someone is moving account between groups */ |
d52aa412 KH |
93 | MEM_CGROUP_STAT_NSTATS, |
94 | }; | |
95 | ||
e9f8974f JW |
96 | enum mem_cgroup_events_index { |
97 | MEM_CGROUP_EVENTS_PGPGIN, /* # of pages paged in */ | |
98 | MEM_CGROUP_EVENTS_PGPGOUT, /* # of pages paged out */ | |
99 | MEM_CGROUP_EVENTS_COUNT, /* # of pages paged in/out */ | |
456f998e YH |
100 | MEM_CGROUP_EVENTS_PGFAULT, /* # of page-faults */ |
101 | MEM_CGROUP_EVENTS_PGMAJFAULT, /* # of major page-faults */ | |
e9f8974f JW |
102 | MEM_CGROUP_EVENTS_NSTATS, |
103 | }; | |
7a159cc9 JW |
104 | /* |
105 | * Per memcg event counter is incremented at every pagein/pageout. With THP, | |
106 | * it will be incremated by the number of pages. This counter is used for | |
107 | * for trigger some periodic events. This is straightforward and better | |
108 | * than using jiffies etc. to handle periodic memcg event. | |
109 | */ | |
110 | enum mem_cgroup_events_target { | |
111 | MEM_CGROUP_TARGET_THRESH, | |
112 | MEM_CGROUP_TARGET_SOFTLIMIT, | |
453a9bf3 | 113 | MEM_CGROUP_TARGET_NUMAINFO, |
7a159cc9 JW |
114 | MEM_CGROUP_NTARGETS, |
115 | }; | |
116 | #define THRESHOLDS_EVENTS_TARGET (128) | |
117 | #define SOFTLIMIT_EVENTS_TARGET (1024) | |
453a9bf3 | 118 | #define NUMAINFO_EVENTS_TARGET (1024) |
e9f8974f | 119 | |
d52aa412 | 120 | struct mem_cgroup_stat_cpu { |
7a159cc9 | 121 | long count[MEM_CGROUP_STAT_NSTATS]; |
e9f8974f | 122 | unsigned long events[MEM_CGROUP_EVENTS_NSTATS]; |
7a159cc9 | 123 | unsigned long targets[MEM_CGROUP_NTARGETS]; |
d52aa412 KH |
124 | }; |
125 | ||
527a5ec9 JW |
126 | struct mem_cgroup_reclaim_iter { |
127 | /* css_id of the last scanned hierarchy member */ | |
128 | int position; | |
129 | /* scan generation, increased every round-trip */ | |
130 | unsigned int generation; | |
131 | }; | |
132 | ||
6d12e2d8 KH |
133 | /* |
134 | * per-zone information in memory controller. | |
135 | */ | |
6d12e2d8 | 136 | struct mem_cgroup_per_zone { |
6290df54 | 137 | struct lruvec lruvec; |
b69408e8 | 138 | unsigned long count[NR_LRU_LISTS]; |
3e2f41f1 | 139 | |
527a5ec9 JW |
140 | struct mem_cgroup_reclaim_iter reclaim_iter[DEF_PRIORITY + 1]; |
141 | ||
3e2f41f1 | 142 | struct zone_reclaim_stat reclaim_stat; |
f64c3f54 BS |
143 | struct rb_node tree_node; /* RB tree node */ |
144 | unsigned long long usage_in_excess;/* Set to the value by which */ | |
145 | /* the soft limit is exceeded*/ | |
146 | bool on_tree; | |
4e416953 BS |
147 | struct mem_cgroup *mem; /* Back pointer, we cannot */ |
148 | /* use container_of */ | |
6d12e2d8 KH |
149 | }; |
150 | /* Macro for accessing counter */ | |
151 | #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)]) | |
152 | ||
153 | struct mem_cgroup_per_node { | |
154 | struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES]; | |
155 | }; | |
156 | ||
157 | struct mem_cgroup_lru_info { | |
158 | struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES]; | |
159 | }; | |
160 | ||
f64c3f54 BS |
161 | /* |
162 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
163 | * their hierarchy representation | |
164 | */ | |
165 | ||
166 | struct mem_cgroup_tree_per_zone { | |
167 | struct rb_root rb_root; | |
168 | spinlock_t lock; | |
169 | }; | |
170 | ||
171 | struct mem_cgroup_tree_per_node { | |
172 | struct mem_cgroup_tree_per_zone rb_tree_per_zone[MAX_NR_ZONES]; | |
173 | }; | |
174 | ||
175 | struct mem_cgroup_tree { | |
176 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
177 | }; | |
178 | ||
179 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
180 | ||
2e72b634 KS |
181 | struct mem_cgroup_threshold { |
182 | struct eventfd_ctx *eventfd; | |
183 | u64 threshold; | |
184 | }; | |
185 | ||
9490ff27 | 186 | /* For threshold */ |
2e72b634 KS |
187 | struct mem_cgroup_threshold_ary { |
188 | /* An array index points to threshold just below usage. */ | |
5407a562 | 189 | int current_threshold; |
2e72b634 KS |
190 | /* Size of entries[] */ |
191 | unsigned int size; | |
192 | /* Array of thresholds */ | |
193 | struct mem_cgroup_threshold entries[0]; | |
194 | }; | |
2c488db2 KS |
195 | |
196 | struct mem_cgroup_thresholds { | |
197 | /* Primary thresholds array */ | |
198 | struct mem_cgroup_threshold_ary *primary; | |
199 | /* | |
200 | * Spare threshold array. | |
201 | * This is needed to make mem_cgroup_unregister_event() "never fail". | |
202 | * It must be able to store at least primary->size - 1 entries. | |
203 | */ | |
204 | struct mem_cgroup_threshold_ary *spare; | |
205 | }; | |
206 | ||
9490ff27 KH |
207 | /* for OOM */ |
208 | struct mem_cgroup_eventfd_list { | |
209 | struct list_head list; | |
210 | struct eventfd_ctx *eventfd; | |
211 | }; | |
2e72b634 | 212 | |
c0ff4b85 R |
213 | static void mem_cgroup_threshold(struct mem_cgroup *memcg); |
214 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); | |
2e72b634 | 215 | |
8cdea7c0 BS |
216 | /* |
217 | * The memory controller data structure. The memory controller controls both | |
218 | * page cache and RSS per cgroup. We would eventually like to provide | |
219 | * statistics based on the statistics developed by Rik Van Riel for clock-pro, | |
220 | * to help the administrator determine what knobs to tune. | |
221 | * | |
222 | * TODO: Add a water mark for the memory controller. Reclaim will begin when | |
8a9f3ccd BS |
223 | * we hit the water mark. May be even add a low water mark, such that |
224 | * no reclaim occurs from a cgroup at it's low water mark, this is | |
225 | * a feature that will be implemented much later in the future. | |
8cdea7c0 BS |
226 | */ |
227 | struct mem_cgroup { | |
228 | struct cgroup_subsys_state css; | |
229 | /* | |
230 | * the counter to account for memory usage | |
231 | */ | |
232 | struct res_counter res; | |
8c7c6e34 KH |
233 | /* |
234 | * the counter to account for mem+swap usage. | |
235 | */ | |
236 | struct res_counter memsw; | |
78fb7466 PE |
237 | /* |
238 | * Per cgroup active and inactive list, similar to the | |
239 | * per zone LRU lists. | |
78fb7466 | 240 | */ |
6d12e2d8 | 241 | struct mem_cgroup_lru_info info; |
889976db YH |
242 | int last_scanned_node; |
243 | #if MAX_NUMNODES > 1 | |
244 | nodemask_t scan_nodes; | |
453a9bf3 KH |
245 | atomic_t numainfo_events; |
246 | atomic_t numainfo_updating; | |
889976db | 247 | #endif |
18f59ea7 BS |
248 | /* |
249 | * Should the accounting and control be hierarchical, per subtree? | |
250 | */ | |
251 | bool use_hierarchy; | |
79dfdacc MH |
252 | |
253 | bool oom_lock; | |
254 | atomic_t under_oom; | |
255 | ||
8c7c6e34 | 256 | atomic_t refcnt; |
14797e23 | 257 | |
1f4c025b | 258 | int swappiness; |
3c11ecf4 KH |
259 | /* OOM-Killer disable */ |
260 | int oom_kill_disable; | |
a7885eb8 | 261 | |
22a668d7 KH |
262 | /* set when res.limit == memsw.limit */ |
263 | bool memsw_is_minimum; | |
264 | ||
2e72b634 KS |
265 | /* protect arrays of thresholds */ |
266 | struct mutex thresholds_lock; | |
267 | ||
268 | /* thresholds for memory usage. RCU-protected */ | |
2c488db2 | 269 | struct mem_cgroup_thresholds thresholds; |
907860ed | 270 | |
2e72b634 | 271 | /* thresholds for mem+swap usage. RCU-protected */ |
2c488db2 | 272 | struct mem_cgroup_thresholds memsw_thresholds; |
907860ed | 273 | |
9490ff27 KH |
274 | /* For oom notifier event fd */ |
275 | struct list_head oom_notify; | |
185efc0f | 276 | |
7dc74be0 DN |
277 | /* |
278 | * Should we move charges of a task when a task is moved into this | |
279 | * mem_cgroup ? And what type of charges should we move ? | |
280 | */ | |
281 | unsigned long move_charge_at_immigrate; | |
d52aa412 | 282 | /* |
c62b1a3b | 283 | * percpu counter. |
d52aa412 | 284 | */ |
c62b1a3b | 285 | struct mem_cgroup_stat_cpu *stat; |
711d3d2c KH |
286 | /* |
287 | * used when a cpu is offlined or other synchronizations | |
288 | * See mem_cgroup_read_stat(). | |
289 | */ | |
290 | struct mem_cgroup_stat_cpu nocpu_base; | |
291 | spinlock_t pcp_counter_lock; | |
d1a4c0b3 GC |
292 | |
293 | #ifdef CONFIG_INET | |
294 | struct tcp_memcontrol tcp_mem; | |
295 | #endif | |
8cdea7c0 BS |
296 | }; |
297 | ||
7dc74be0 DN |
298 | /* Stuffs for move charges at task migration. */ |
299 | /* | |
300 | * Types of charges to be moved. "move_charge_at_immitgrate" is treated as a | |
301 | * left-shifted bitmap of these types. | |
302 | */ | |
303 | enum move_type { | |
4ffef5fe | 304 | MOVE_CHARGE_TYPE_ANON, /* private anonymous page and swap of it */ |
87946a72 | 305 | MOVE_CHARGE_TYPE_FILE, /* file page(including tmpfs) and swap of it */ |
7dc74be0 DN |
306 | NR_MOVE_TYPE, |
307 | }; | |
308 | ||
4ffef5fe DN |
309 | /* "mc" and its members are protected by cgroup_mutex */ |
310 | static struct move_charge_struct { | |
b1dd693e | 311 | spinlock_t lock; /* for from, to */ |
4ffef5fe DN |
312 | struct mem_cgroup *from; |
313 | struct mem_cgroup *to; | |
314 | unsigned long precharge; | |
854ffa8d | 315 | unsigned long moved_charge; |
483c30b5 | 316 | unsigned long moved_swap; |
8033b97c DN |
317 | struct task_struct *moving_task; /* a task moving charges */ |
318 | wait_queue_head_t waitq; /* a waitq for other context */ | |
319 | } mc = { | |
2bd9bb20 | 320 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
321 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
322 | }; | |
4ffef5fe | 323 | |
90254a65 DN |
324 | static bool move_anon(void) |
325 | { | |
326 | return test_bit(MOVE_CHARGE_TYPE_ANON, | |
327 | &mc.to->move_charge_at_immigrate); | |
328 | } | |
329 | ||
87946a72 DN |
330 | static bool move_file(void) |
331 | { | |
332 | return test_bit(MOVE_CHARGE_TYPE_FILE, | |
333 | &mc.to->move_charge_at_immigrate); | |
334 | } | |
335 | ||
4e416953 BS |
336 | /* |
337 | * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft | |
338 | * limit reclaim to prevent infinite loops, if they ever occur. | |
339 | */ | |
340 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS (100) | |
341 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS (2) | |
342 | ||
217bc319 KH |
343 | enum charge_type { |
344 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, | |
345 | MEM_CGROUP_CHARGE_TYPE_MAPPED, | |
4f98a2fe | 346 | MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ |
c05555b5 | 347 | MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ |
d13d1443 | 348 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
8a9478ca | 349 | MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ |
c05555b5 KH |
350 | NR_CHARGE_TYPE, |
351 | }; | |
352 | ||
8c7c6e34 | 353 | /* for encoding cft->private value on file */ |
65c64ce8 GC |
354 | #define _MEM (0) |
355 | #define _MEMSWAP (1) | |
356 | #define _OOM_TYPE (2) | |
8c7c6e34 KH |
357 | #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val)) |
358 | #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff) | |
359 | #define MEMFILE_ATTR(val) ((val) & 0xffff) | |
9490ff27 KH |
360 | /* Used for OOM nofiier */ |
361 | #define OOM_CONTROL (0) | |
8c7c6e34 | 362 | |
75822b44 BS |
363 | /* |
364 | * Reclaim flags for mem_cgroup_hierarchical_reclaim | |
365 | */ | |
366 | #define MEM_CGROUP_RECLAIM_NOSWAP_BIT 0x0 | |
367 | #define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT) | |
368 | #define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1 | |
369 | #define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT) | |
370 | ||
c0ff4b85 R |
371 | static void mem_cgroup_get(struct mem_cgroup *memcg); |
372 | static void mem_cgroup_put(struct mem_cgroup *memcg); | |
e1aab161 GC |
373 | |
374 | /* Writing them here to avoid exposing memcg's inner layout */ | |
375 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM | |
376 | #ifdef CONFIG_INET | |
377 | #include <net/sock.h> | |
d1a4c0b3 | 378 | #include <net/ip.h> |
e1aab161 GC |
379 | |
380 | static bool mem_cgroup_is_root(struct mem_cgroup *memcg); | |
381 | void sock_update_memcg(struct sock *sk) | |
382 | { | |
e1aab161 GC |
383 | if (static_branch(&memcg_socket_limit_enabled)) { |
384 | struct mem_cgroup *memcg; | |
385 | ||
386 | BUG_ON(!sk->sk_prot->proto_cgroup); | |
387 | ||
f3f511e1 GC |
388 | /* Socket cloning can throw us here with sk_cgrp already |
389 | * filled. It won't however, necessarily happen from | |
390 | * process context. So the test for root memcg given | |
391 | * the current task's memcg won't help us in this case. | |
392 | * | |
393 | * Respecting the original socket's memcg is a better | |
394 | * decision in this case. | |
395 | */ | |
396 | if (sk->sk_cgrp) { | |
397 | BUG_ON(mem_cgroup_is_root(sk->sk_cgrp->memcg)); | |
398 | mem_cgroup_get(sk->sk_cgrp->memcg); | |
399 | return; | |
400 | } | |
401 | ||
e1aab161 GC |
402 | rcu_read_lock(); |
403 | memcg = mem_cgroup_from_task(current); | |
404 | if (!mem_cgroup_is_root(memcg)) { | |
405 | mem_cgroup_get(memcg); | |
406 | sk->sk_cgrp = sk->sk_prot->proto_cgroup(memcg); | |
407 | } | |
408 | rcu_read_unlock(); | |
409 | } | |
410 | } | |
411 | EXPORT_SYMBOL(sock_update_memcg); | |
412 | ||
413 | void sock_release_memcg(struct sock *sk) | |
414 | { | |
415 | if (static_branch(&memcg_socket_limit_enabled) && sk->sk_cgrp) { | |
416 | struct mem_cgroup *memcg; | |
417 | WARN_ON(!sk->sk_cgrp->memcg); | |
418 | memcg = sk->sk_cgrp->memcg; | |
419 | mem_cgroup_put(memcg); | |
420 | } | |
421 | } | |
d1a4c0b3 GC |
422 | |
423 | struct cg_proto *tcp_proto_cgroup(struct mem_cgroup *memcg) | |
424 | { | |
425 | if (!memcg || mem_cgroup_is_root(memcg)) | |
426 | return NULL; | |
427 | ||
428 | return &memcg->tcp_mem.cg_proto; | |
429 | } | |
430 | EXPORT_SYMBOL(tcp_proto_cgroup); | |
e1aab161 GC |
431 | #endif /* CONFIG_INET */ |
432 | #endif /* CONFIG_CGROUP_MEM_RES_CTLR_KMEM */ | |
433 | ||
c0ff4b85 | 434 | static void drain_all_stock_async(struct mem_cgroup *memcg); |
8c7c6e34 | 435 | |
f64c3f54 | 436 | static struct mem_cgroup_per_zone * |
c0ff4b85 | 437 | mem_cgroup_zoneinfo(struct mem_cgroup *memcg, int nid, int zid) |
f64c3f54 | 438 | { |
c0ff4b85 | 439 | return &memcg->info.nodeinfo[nid]->zoneinfo[zid]; |
f64c3f54 BS |
440 | } |
441 | ||
c0ff4b85 | 442 | struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *memcg) |
d324236b | 443 | { |
c0ff4b85 | 444 | return &memcg->css; |
d324236b WF |
445 | } |
446 | ||
f64c3f54 | 447 | static struct mem_cgroup_per_zone * |
c0ff4b85 | 448 | page_cgroup_zoneinfo(struct mem_cgroup *memcg, struct page *page) |
f64c3f54 | 449 | { |
97a6c37b JW |
450 | int nid = page_to_nid(page); |
451 | int zid = page_zonenum(page); | |
f64c3f54 | 452 | |
c0ff4b85 | 453 | return mem_cgroup_zoneinfo(memcg, nid, zid); |
f64c3f54 BS |
454 | } |
455 | ||
456 | static struct mem_cgroup_tree_per_zone * | |
457 | soft_limit_tree_node_zone(int nid, int zid) | |
458 | { | |
459 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
460 | } | |
461 | ||
462 | static struct mem_cgroup_tree_per_zone * | |
463 | soft_limit_tree_from_page(struct page *page) | |
464 | { | |
465 | int nid = page_to_nid(page); | |
466 | int zid = page_zonenum(page); | |
467 | ||
468 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
469 | } | |
470 | ||
471 | static void | |
c0ff4b85 | 472 | __mem_cgroup_insert_exceeded(struct mem_cgroup *memcg, |
f64c3f54 | 473 | struct mem_cgroup_per_zone *mz, |
ef8745c1 KH |
474 | struct mem_cgroup_tree_per_zone *mctz, |
475 | unsigned long long new_usage_in_excess) | |
f64c3f54 BS |
476 | { |
477 | struct rb_node **p = &mctz->rb_root.rb_node; | |
478 | struct rb_node *parent = NULL; | |
479 | struct mem_cgroup_per_zone *mz_node; | |
480 | ||
481 | if (mz->on_tree) | |
482 | return; | |
483 | ||
ef8745c1 KH |
484 | mz->usage_in_excess = new_usage_in_excess; |
485 | if (!mz->usage_in_excess) | |
486 | return; | |
f64c3f54 BS |
487 | while (*p) { |
488 | parent = *p; | |
489 | mz_node = rb_entry(parent, struct mem_cgroup_per_zone, | |
490 | tree_node); | |
491 | if (mz->usage_in_excess < mz_node->usage_in_excess) | |
492 | p = &(*p)->rb_left; | |
493 | /* | |
494 | * We can't avoid mem cgroups that are over their soft | |
495 | * limit by the same amount | |
496 | */ | |
497 | else if (mz->usage_in_excess >= mz_node->usage_in_excess) | |
498 | p = &(*p)->rb_right; | |
499 | } | |
500 | rb_link_node(&mz->tree_node, parent, p); | |
501 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
502 | mz->on_tree = true; | |
4e416953 BS |
503 | } |
504 | ||
505 | static void | |
c0ff4b85 | 506 | __mem_cgroup_remove_exceeded(struct mem_cgroup *memcg, |
4e416953 BS |
507 | struct mem_cgroup_per_zone *mz, |
508 | struct mem_cgroup_tree_per_zone *mctz) | |
509 | { | |
510 | if (!mz->on_tree) | |
511 | return; | |
512 | rb_erase(&mz->tree_node, &mctz->rb_root); | |
513 | mz->on_tree = false; | |
514 | } | |
515 | ||
f64c3f54 | 516 | static void |
c0ff4b85 | 517 | mem_cgroup_remove_exceeded(struct mem_cgroup *memcg, |
f64c3f54 BS |
518 | struct mem_cgroup_per_zone *mz, |
519 | struct mem_cgroup_tree_per_zone *mctz) | |
520 | { | |
521 | spin_lock(&mctz->lock); | |
c0ff4b85 | 522 | __mem_cgroup_remove_exceeded(memcg, mz, mctz); |
f64c3f54 BS |
523 | spin_unlock(&mctz->lock); |
524 | } | |
525 | ||
f64c3f54 | 526 | |
c0ff4b85 | 527 | static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page) |
f64c3f54 | 528 | { |
ef8745c1 | 529 | unsigned long long excess; |
f64c3f54 BS |
530 | struct mem_cgroup_per_zone *mz; |
531 | struct mem_cgroup_tree_per_zone *mctz; | |
4e649152 KH |
532 | int nid = page_to_nid(page); |
533 | int zid = page_zonenum(page); | |
f64c3f54 BS |
534 | mctz = soft_limit_tree_from_page(page); |
535 | ||
536 | /* | |
4e649152 KH |
537 | * Necessary to update all ancestors when hierarchy is used. |
538 | * because their event counter is not touched. | |
f64c3f54 | 539 | */ |
c0ff4b85 R |
540 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { |
541 | mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
542 | excess = res_counter_soft_limit_excess(&memcg->res); | |
4e649152 KH |
543 | /* |
544 | * We have to update the tree if mz is on RB-tree or | |
545 | * mem is over its softlimit. | |
546 | */ | |
ef8745c1 | 547 | if (excess || mz->on_tree) { |
4e649152 KH |
548 | spin_lock(&mctz->lock); |
549 | /* if on-tree, remove it */ | |
550 | if (mz->on_tree) | |
c0ff4b85 | 551 | __mem_cgroup_remove_exceeded(memcg, mz, mctz); |
4e649152 | 552 | /* |
ef8745c1 KH |
553 | * Insert again. mz->usage_in_excess will be updated. |
554 | * If excess is 0, no tree ops. | |
4e649152 | 555 | */ |
c0ff4b85 | 556 | __mem_cgroup_insert_exceeded(memcg, mz, mctz, excess); |
4e649152 KH |
557 | spin_unlock(&mctz->lock); |
558 | } | |
f64c3f54 BS |
559 | } |
560 | } | |
561 | ||
c0ff4b85 | 562 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) |
f64c3f54 BS |
563 | { |
564 | int node, zone; | |
565 | struct mem_cgroup_per_zone *mz; | |
566 | struct mem_cgroup_tree_per_zone *mctz; | |
567 | ||
568 | for_each_node_state(node, N_POSSIBLE) { | |
569 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
c0ff4b85 | 570 | mz = mem_cgroup_zoneinfo(memcg, node, zone); |
f64c3f54 | 571 | mctz = soft_limit_tree_node_zone(node, zone); |
c0ff4b85 | 572 | mem_cgroup_remove_exceeded(memcg, mz, mctz); |
f64c3f54 BS |
573 | } |
574 | } | |
575 | } | |
576 | ||
4e416953 BS |
577 | static struct mem_cgroup_per_zone * |
578 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
579 | { | |
580 | struct rb_node *rightmost = NULL; | |
26251eaf | 581 | struct mem_cgroup_per_zone *mz; |
4e416953 BS |
582 | |
583 | retry: | |
26251eaf | 584 | mz = NULL; |
4e416953 BS |
585 | rightmost = rb_last(&mctz->rb_root); |
586 | if (!rightmost) | |
587 | goto done; /* Nothing to reclaim from */ | |
588 | ||
589 | mz = rb_entry(rightmost, struct mem_cgroup_per_zone, tree_node); | |
590 | /* | |
591 | * Remove the node now but someone else can add it back, | |
592 | * we will to add it back at the end of reclaim to its correct | |
593 | * position in the tree. | |
594 | */ | |
595 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); | |
596 | if (!res_counter_soft_limit_excess(&mz->mem->res) || | |
597 | !css_tryget(&mz->mem->css)) | |
598 | goto retry; | |
599 | done: | |
600 | return mz; | |
601 | } | |
602 | ||
603 | static struct mem_cgroup_per_zone * | |
604 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
605 | { | |
606 | struct mem_cgroup_per_zone *mz; | |
607 | ||
608 | spin_lock(&mctz->lock); | |
609 | mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
610 | spin_unlock(&mctz->lock); | |
611 | return mz; | |
612 | } | |
613 | ||
711d3d2c KH |
614 | /* |
615 | * Implementation Note: reading percpu statistics for memcg. | |
616 | * | |
617 | * Both of vmstat[] and percpu_counter has threshold and do periodic | |
618 | * synchronization to implement "quick" read. There are trade-off between | |
619 | * reading cost and precision of value. Then, we may have a chance to implement | |
620 | * a periodic synchronizion of counter in memcg's counter. | |
621 | * | |
622 | * But this _read() function is used for user interface now. The user accounts | |
623 | * memory usage by memory cgroup and he _always_ requires exact value because | |
624 | * he accounts memory. Even if we provide quick-and-fuzzy read, we always | |
625 | * have to visit all online cpus and make sum. So, for now, unnecessary | |
626 | * synchronization is not implemented. (just implemented for cpu hotplug) | |
627 | * | |
628 | * If there are kernel internal actions which can make use of some not-exact | |
629 | * value, and reading all cpu value can be performance bottleneck in some | |
630 | * common workload, threashold and synchonization as vmstat[] should be | |
631 | * implemented. | |
632 | */ | |
c0ff4b85 | 633 | static long mem_cgroup_read_stat(struct mem_cgroup *memcg, |
7a159cc9 | 634 | enum mem_cgroup_stat_index idx) |
c62b1a3b | 635 | { |
7a159cc9 | 636 | long val = 0; |
c62b1a3b | 637 | int cpu; |
c62b1a3b | 638 | |
711d3d2c KH |
639 | get_online_cpus(); |
640 | for_each_online_cpu(cpu) | |
c0ff4b85 | 641 | val += per_cpu(memcg->stat->count[idx], cpu); |
711d3d2c | 642 | #ifdef CONFIG_HOTPLUG_CPU |
c0ff4b85 R |
643 | spin_lock(&memcg->pcp_counter_lock); |
644 | val += memcg->nocpu_base.count[idx]; | |
645 | spin_unlock(&memcg->pcp_counter_lock); | |
711d3d2c KH |
646 | #endif |
647 | put_online_cpus(); | |
c62b1a3b KH |
648 | return val; |
649 | } | |
650 | ||
c0ff4b85 | 651 | static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg, |
0c3e73e8 BS |
652 | bool charge) |
653 | { | |
654 | int val = (charge) ? 1 : -1; | |
c0ff4b85 | 655 | this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_SWAPOUT], val); |
0c3e73e8 BS |
656 | } |
657 | ||
c0ff4b85 | 658 | static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg, |
e9f8974f JW |
659 | enum mem_cgroup_events_index idx) |
660 | { | |
661 | unsigned long val = 0; | |
662 | int cpu; | |
663 | ||
664 | for_each_online_cpu(cpu) | |
c0ff4b85 | 665 | val += per_cpu(memcg->stat->events[idx], cpu); |
e9f8974f | 666 | #ifdef CONFIG_HOTPLUG_CPU |
c0ff4b85 R |
667 | spin_lock(&memcg->pcp_counter_lock); |
668 | val += memcg->nocpu_base.events[idx]; | |
669 | spin_unlock(&memcg->pcp_counter_lock); | |
e9f8974f JW |
670 | #endif |
671 | return val; | |
672 | } | |
673 | ||
c0ff4b85 | 674 | static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, |
e401f176 | 675 | bool file, int nr_pages) |
d52aa412 | 676 | { |
c62b1a3b KH |
677 | preempt_disable(); |
678 | ||
e401f176 | 679 | if (file) |
c0ff4b85 R |
680 | __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_CACHE], |
681 | nr_pages); | |
d52aa412 | 682 | else |
c0ff4b85 R |
683 | __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_RSS], |
684 | nr_pages); | |
55e462b0 | 685 | |
e401f176 KH |
686 | /* pagein of a big page is an event. So, ignore page size */ |
687 | if (nr_pages > 0) | |
c0ff4b85 | 688 | __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGIN]); |
3751d604 | 689 | else { |
c0ff4b85 | 690 | __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT]); |
3751d604 KH |
691 | nr_pages = -nr_pages; /* for event */ |
692 | } | |
e401f176 | 693 | |
c0ff4b85 | 694 | __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_COUNT], nr_pages); |
2e72b634 | 695 | |
c62b1a3b | 696 | preempt_enable(); |
6d12e2d8 KH |
697 | } |
698 | ||
bb2a0de9 | 699 | unsigned long |
c0ff4b85 | 700 | mem_cgroup_zone_nr_lru_pages(struct mem_cgroup *memcg, int nid, int zid, |
bb2a0de9 | 701 | unsigned int lru_mask) |
889976db YH |
702 | { |
703 | struct mem_cgroup_per_zone *mz; | |
bb2a0de9 KH |
704 | enum lru_list l; |
705 | unsigned long ret = 0; | |
706 | ||
c0ff4b85 | 707 | mz = mem_cgroup_zoneinfo(memcg, nid, zid); |
bb2a0de9 KH |
708 | |
709 | for_each_lru(l) { | |
710 | if (BIT(l) & lru_mask) | |
711 | ret += MEM_CGROUP_ZSTAT(mz, l); | |
712 | } | |
713 | return ret; | |
714 | } | |
715 | ||
716 | static unsigned long | |
c0ff4b85 | 717 | mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, |
bb2a0de9 KH |
718 | int nid, unsigned int lru_mask) |
719 | { | |
889976db YH |
720 | u64 total = 0; |
721 | int zid; | |
722 | ||
bb2a0de9 | 723 | for (zid = 0; zid < MAX_NR_ZONES; zid++) |
c0ff4b85 R |
724 | total += mem_cgroup_zone_nr_lru_pages(memcg, |
725 | nid, zid, lru_mask); | |
bb2a0de9 | 726 | |
889976db YH |
727 | return total; |
728 | } | |
bb2a0de9 | 729 | |
c0ff4b85 | 730 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, |
bb2a0de9 | 731 | unsigned int lru_mask) |
6d12e2d8 | 732 | { |
889976db | 733 | int nid; |
6d12e2d8 KH |
734 | u64 total = 0; |
735 | ||
bb2a0de9 | 736 | for_each_node_state(nid, N_HIGH_MEMORY) |
c0ff4b85 | 737 | total += mem_cgroup_node_nr_lru_pages(memcg, nid, lru_mask); |
6d12e2d8 | 738 | return total; |
d52aa412 KH |
739 | } |
740 | ||
f53d7ce3 JW |
741 | static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg, |
742 | enum mem_cgroup_events_target target) | |
7a159cc9 JW |
743 | { |
744 | unsigned long val, next; | |
745 | ||
4799401f SR |
746 | val = __this_cpu_read(memcg->stat->events[MEM_CGROUP_EVENTS_COUNT]); |
747 | next = __this_cpu_read(memcg->stat->targets[target]); | |
7a159cc9 | 748 | /* from time_after() in jiffies.h */ |
f53d7ce3 JW |
749 | if ((long)next - (long)val < 0) { |
750 | switch (target) { | |
751 | case MEM_CGROUP_TARGET_THRESH: | |
752 | next = val + THRESHOLDS_EVENTS_TARGET; | |
753 | break; | |
754 | case MEM_CGROUP_TARGET_SOFTLIMIT: | |
755 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
756 | break; | |
757 | case MEM_CGROUP_TARGET_NUMAINFO: | |
758 | next = val + NUMAINFO_EVENTS_TARGET; | |
759 | break; | |
760 | default: | |
761 | break; | |
762 | } | |
763 | __this_cpu_write(memcg->stat->targets[target], next); | |
764 | return true; | |
7a159cc9 | 765 | } |
f53d7ce3 | 766 | return false; |
d2265e6f KH |
767 | } |
768 | ||
769 | /* | |
770 | * Check events in order. | |
771 | * | |
772 | */ | |
c0ff4b85 | 773 | static void memcg_check_events(struct mem_cgroup *memcg, struct page *page) |
d2265e6f | 774 | { |
4799401f | 775 | preempt_disable(); |
d2265e6f | 776 | /* threshold event is triggered in finer grain than soft limit */ |
f53d7ce3 JW |
777 | if (unlikely(mem_cgroup_event_ratelimit(memcg, |
778 | MEM_CGROUP_TARGET_THRESH))) { | |
779 | bool do_softlimit, do_numainfo; | |
780 | ||
781 | do_softlimit = mem_cgroup_event_ratelimit(memcg, | |
782 | MEM_CGROUP_TARGET_SOFTLIMIT); | |
783 | #if MAX_NUMNODES > 1 | |
784 | do_numainfo = mem_cgroup_event_ratelimit(memcg, | |
785 | MEM_CGROUP_TARGET_NUMAINFO); | |
786 | #endif | |
787 | preempt_enable(); | |
788 | ||
c0ff4b85 | 789 | mem_cgroup_threshold(memcg); |
f53d7ce3 | 790 | if (unlikely(do_softlimit)) |
c0ff4b85 | 791 | mem_cgroup_update_tree(memcg, page); |
453a9bf3 | 792 | #if MAX_NUMNODES > 1 |
f53d7ce3 | 793 | if (unlikely(do_numainfo)) |
c0ff4b85 | 794 | atomic_inc(&memcg->numainfo_events); |
453a9bf3 | 795 | #endif |
f53d7ce3 JW |
796 | } else |
797 | preempt_enable(); | |
d2265e6f KH |
798 | } |
799 | ||
d1a4c0b3 | 800 | struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) |
8cdea7c0 BS |
801 | { |
802 | return container_of(cgroup_subsys_state(cont, | |
803 | mem_cgroup_subsys_id), struct mem_cgroup, | |
804 | css); | |
805 | } | |
806 | ||
cf475ad2 | 807 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 808 | { |
31a78f23 BS |
809 | /* |
810 | * mm_update_next_owner() may clear mm->owner to NULL | |
811 | * if it races with swapoff, page migration, etc. | |
812 | * So this can be called with p == NULL. | |
813 | */ | |
814 | if (unlikely(!p)) | |
815 | return NULL; | |
816 | ||
78fb7466 PE |
817 | return container_of(task_subsys_state(p, mem_cgroup_subsys_id), |
818 | struct mem_cgroup, css); | |
819 | } | |
820 | ||
a433658c | 821 | struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) |
54595fe2 | 822 | { |
c0ff4b85 | 823 | struct mem_cgroup *memcg = NULL; |
0b7f569e KH |
824 | |
825 | if (!mm) | |
826 | return NULL; | |
54595fe2 KH |
827 | /* |
828 | * Because we have no locks, mm->owner's may be being moved to other | |
829 | * cgroup. We use css_tryget() here even if this looks | |
830 | * pessimistic (rather than adding locks here). | |
831 | */ | |
832 | rcu_read_lock(); | |
833 | do { | |
c0ff4b85 R |
834 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); |
835 | if (unlikely(!memcg)) | |
54595fe2 | 836 | break; |
c0ff4b85 | 837 | } while (!css_tryget(&memcg->css)); |
54595fe2 | 838 | rcu_read_unlock(); |
c0ff4b85 | 839 | return memcg; |
54595fe2 KH |
840 | } |
841 | ||
5660048c JW |
842 | /** |
843 | * mem_cgroup_iter - iterate over memory cgroup hierarchy | |
844 | * @root: hierarchy root | |
845 | * @prev: previously returned memcg, NULL on first invocation | |
846 | * @reclaim: cookie for shared reclaim walks, NULL for full walks | |
847 | * | |
848 | * Returns references to children of the hierarchy below @root, or | |
849 | * @root itself, or %NULL after a full round-trip. | |
850 | * | |
851 | * Caller must pass the return value in @prev on subsequent | |
852 | * invocations for reference counting, or use mem_cgroup_iter_break() | |
853 | * to cancel a hierarchy walk before the round-trip is complete. | |
854 | * | |
855 | * Reclaimers can specify a zone and a priority level in @reclaim to | |
856 | * divide up the memcgs in the hierarchy among all concurrent | |
857 | * reclaimers operating on the same zone and priority. | |
858 | */ | |
859 | struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, | |
860 | struct mem_cgroup *prev, | |
861 | struct mem_cgroup_reclaim_cookie *reclaim) | |
14067bb3 | 862 | { |
9f3a0d09 JW |
863 | struct mem_cgroup *memcg = NULL; |
864 | int id = 0; | |
711d3d2c | 865 | |
5660048c JW |
866 | if (mem_cgroup_disabled()) |
867 | return NULL; | |
868 | ||
9f3a0d09 JW |
869 | if (!root) |
870 | root = root_mem_cgroup; | |
7d74b06f | 871 | |
9f3a0d09 JW |
872 | if (prev && !reclaim) |
873 | id = css_id(&prev->css); | |
14067bb3 | 874 | |
9f3a0d09 JW |
875 | if (prev && prev != root) |
876 | css_put(&prev->css); | |
14067bb3 | 877 | |
9f3a0d09 JW |
878 | if (!root->use_hierarchy && root != root_mem_cgroup) { |
879 | if (prev) | |
880 | return NULL; | |
881 | return root; | |
882 | } | |
14067bb3 | 883 | |
9f3a0d09 | 884 | while (!memcg) { |
527a5ec9 | 885 | struct mem_cgroup_reclaim_iter *uninitialized_var(iter); |
9f3a0d09 | 886 | struct cgroup_subsys_state *css; |
711d3d2c | 887 | |
527a5ec9 JW |
888 | if (reclaim) { |
889 | int nid = zone_to_nid(reclaim->zone); | |
890 | int zid = zone_idx(reclaim->zone); | |
891 | struct mem_cgroup_per_zone *mz; | |
892 | ||
893 | mz = mem_cgroup_zoneinfo(root, nid, zid); | |
894 | iter = &mz->reclaim_iter[reclaim->priority]; | |
895 | if (prev && reclaim->generation != iter->generation) | |
896 | return NULL; | |
897 | id = iter->position; | |
898 | } | |
7d74b06f | 899 | |
9f3a0d09 JW |
900 | rcu_read_lock(); |
901 | css = css_get_next(&mem_cgroup_subsys, id + 1, &root->css, &id); | |
902 | if (css) { | |
903 | if (css == &root->css || css_tryget(css)) | |
904 | memcg = container_of(css, | |
905 | struct mem_cgroup, css); | |
906 | } else | |
907 | id = 0; | |
14067bb3 | 908 | rcu_read_unlock(); |
14067bb3 | 909 | |
527a5ec9 JW |
910 | if (reclaim) { |
911 | iter->position = id; | |
912 | if (!css) | |
913 | iter->generation++; | |
914 | else if (!prev && memcg) | |
915 | reclaim->generation = iter->generation; | |
916 | } | |
9f3a0d09 JW |
917 | |
918 | if (prev && !css) | |
919 | return NULL; | |
920 | } | |
921 | return memcg; | |
14067bb3 | 922 | } |
7d74b06f | 923 | |
5660048c JW |
924 | /** |
925 | * mem_cgroup_iter_break - abort a hierarchy walk prematurely | |
926 | * @root: hierarchy root | |
927 | * @prev: last visited hierarchy member as returned by mem_cgroup_iter() | |
928 | */ | |
929 | void mem_cgroup_iter_break(struct mem_cgroup *root, | |
930 | struct mem_cgroup *prev) | |
9f3a0d09 JW |
931 | { |
932 | if (!root) | |
933 | root = root_mem_cgroup; | |
934 | if (prev && prev != root) | |
935 | css_put(&prev->css); | |
936 | } | |
7d74b06f | 937 | |
9f3a0d09 JW |
938 | /* |
939 | * Iteration constructs for visiting all cgroups (under a tree). If | |
940 | * loops are exited prematurely (break), mem_cgroup_iter_break() must | |
941 | * be used for reference counting. | |
942 | */ | |
943 | #define for_each_mem_cgroup_tree(iter, root) \ | |
527a5ec9 | 944 | for (iter = mem_cgroup_iter(root, NULL, NULL); \ |
9f3a0d09 | 945 | iter != NULL; \ |
527a5ec9 | 946 | iter = mem_cgroup_iter(root, iter, NULL)) |
711d3d2c | 947 | |
9f3a0d09 | 948 | #define for_each_mem_cgroup(iter) \ |
527a5ec9 | 949 | for (iter = mem_cgroup_iter(NULL, NULL, NULL); \ |
9f3a0d09 | 950 | iter != NULL; \ |
527a5ec9 | 951 | iter = mem_cgroup_iter(NULL, iter, NULL)) |
14067bb3 | 952 | |
c0ff4b85 | 953 | static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) |
4b3bde4c | 954 | { |
c0ff4b85 | 955 | return (memcg == root_mem_cgroup); |
4b3bde4c BS |
956 | } |
957 | ||
456f998e YH |
958 | void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) |
959 | { | |
c0ff4b85 | 960 | struct mem_cgroup *memcg; |
456f998e YH |
961 | |
962 | if (!mm) | |
963 | return; | |
964 | ||
965 | rcu_read_lock(); | |
c0ff4b85 R |
966 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); |
967 | if (unlikely(!memcg)) | |
456f998e YH |
968 | goto out; |
969 | ||
970 | switch (idx) { | |
456f998e | 971 | case PGFAULT: |
0e574a93 JW |
972 | this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT]); |
973 | break; | |
974 | case PGMAJFAULT: | |
975 | this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT]); | |
456f998e YH |
976 | break; |
977 | default: | |
978 | BUG(); | |
979 | } | |
980 | out: | |
981 | rcu_read_unlock(); | |
982 | } | |
983 | EXPORT_SYMBOL(mem_cgroup_count_vm_event); | |
984 | ||
925b7673 JW |
985 | /** |
986 | * mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg | |
987 | * @zone: zone of the wanted lruvec | |
988 | * @mem: memcg of the wanted lruvec | |
989 | * | |
990 | * Returns the lru list vector holding pages for the given @zone and | |
991 | * @mem. This can be the global zone lruvec, if the memory controller | |
992 | * is disabled. | |
993 | */ | |
994 | struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone, | |
995 | struct mem_cgroup *memcg) | |
996 | { | |
997 | struct mem_cgroup_per_zone *mz; | |
998 | ||
999 | if (mem_cgroup_disabled()) | |
1000 | return &zone->lruvec; | |
1001 | ||
1002 | mz = mem_cgroup_zoneinfo(memcg, zone_to_nid(zone), zone_idx(zone)); | |
1003 | return &mz->lruvec; | |
1004 | } | |
1005 | ||
08e552c6 KH |
1006 | /* |
1007 | * Following LRU functions are allowed to be used without PCG_LOCK. | |
1008 | * Operations are called by routine of global LRU independently from memcg. | |
1009 | * What we have to take care of here is validness of pc->mem_cgroup. | |
1010 | * | |
1011 | * Changes to pc->mem_cgroup happens when | |
1012 | * 1. charge | |
1013 | * 2. moving account | |
1014 | * In typical case, "charge" is done before add-to-lru. Exception is SwapCache. | |
1015 | * It is added to LRU before charge. | |
1016 | * If PCG_USED bit is not set, page_cgroup is not added to this private LRU. | |
1017 | * When moving account, the page is not on LRU. It's isolated. | |
1018 | */ | |
4f98a2fe | 1019 | |
925b7673 JW |
1020 | /** |
1021 | * mem_cgroup_lru_add_list - account for adding an lru page and return lruvec | |
1022 | * @zone: zone of the page | |
1023 | * @page: the page | |
1024 | * @lru: current lru | |
1025 | * | |
1026 | * This function accounts for @page being added to @lru, and returns | |
1027 | * the lruvec for the given @zone and the memcg @page is charged to. | |
1028 | * | |
1029 | * The callsite is then responsible for physically linking the page to | |
1030 | * the returned lruvec->lists[@lru]. | |
1031 | */ | |
1032 | struct lruvec *mem_cgroup_lru_add_list(struct zone *zone, struct page *page, | |
1033 | enum lru_list lru) | |
08e552c6 | 1034 | { |
08e552c6 | 1035 | struct mem_cgroup_per_zone *mz; |
925b7673 JW |
1036 | struct mem_cgroup *memcg; |
1037 | struct page_cgroup *pc; | |
6d12e2d8 | 1038 | |
f8d66542 | 1039 | if (mem_cgroup_disabled()) |
925b7673 JW |
1040 | return &zone->lruvec; |
1041 | ||
08e552c6 | 1042 | pc = lookup_page_cgroup(page); |
925b7673 | 1043 | VM_BUG_ON(PageCgroupAcctLRU(pc)); |
544122e5 | 1044 | /* |
925b7673 JW |
1045 | * putback: charge: |
1046 | * SetPageLRU SetPageCgroupUsed | |
1047 | * smp_mb smp_mb | |
1048 | * PageCgroupUsed && add to memcg LRU PageLRU && add to memcg LRU | |
1049 | * | |
1050 | * Ensure that one of the two sides adds the page to the memcg | |
1051 | * LRU during a race. | |
544122e5 | 1052 | */ |
925b7673 JW |
1053 | smp_mb(); |
1054 | /* | |
1055 | * If the page is uncharged, it may be freed soon, but it | |
1056 | * could also be swap cache (readahead, swapoff) that needs to | |
1057 | * be reclaimable in the future. root_mem_cgroup will babysit | |
1058 | * it for the time being. | |
1059 | */ | |
1060 | if (PageCgroupUsed(pc)) { | |
1061 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ | |
1062 | smp_rmb(); | |
1063 | memcg = pc->mem_cgroup; | |
1064 | SetPageCgroupAcctLRU(pc); | |
1065 | } else | |
1066 | memcg = root_mem_cgroup; | |
1067 | mz = page_cgroup_zoneinfo(memcg, page); | |
1068 | /* compound_order() is stabilized through lru_lock */ | |
1069 | MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page); | |
1070 | return &mz->lruvec; | |
08e552c6 | 1071 | } |
b69408e8 | 1072 | |
925b7673 JW |
1073 | /** |
1074 | * mem_cgroup_lru_del_list - account for removing an lru page | |
1075 | * @page: the page | |
1076 | * @lru: target lru | |
1077 | * | |
1078 | * This function accounts for @page being removed from @lru. | |
1079 | * | |
1080 | * The callsite is then responsible for physically unlinking | |
1081 | * @page->lru. | |
3f58a829 | 1082 | */ |
925b7673 | 1083 | void mem_cgroup_lru_del_list(struct page *page, enum lru_list lru) |
3f58a829 MK |
1084 | { |
1085 | struct mem_cgroup_per_zone *mz; | |
925b7673 | 1086 | struct mem_cgroup *memcg; |
3f58a829 | 1087 | struct page_cgroup *pc; |
3f58a829 MK |
1088 | |
1089 | if (mem_cgroup_disabled()) | |
1090 | return; | |
1091 | ||
1092 | pc = lookup_page_cgroup(page); | |
925b7673 JW |
1093 | /* |
1094 | * root_mem_cgroup babysits uncharged LRU pages, but | |
1095 | * PageCgroupUsed is cleared when the page is about to get | |
1096 | * freed. PageCgroupAcctLRU remembers whether the | |
1097 | * LRU-accounting happened against pc->mem_cgroup or | |
1098 | * root_mem_cgroup. | |
1099 | */ | |
1100 | if (TestClearPageCgroupAcctLRU(pc)) { | |
1101 | VM_BUG_ON(!pc->mem_cgroup); | |
1102 | memcg = pc->mem_cgroup; | |
1103 | } else | |
1104 | memcg = root_mem_cgroup; | |
1105 | mz = page_cgroup_zoneinfo(memcg, page); | |
1106 | /* huge page split is done under lru_lock. so, we have no races. */ | |
1107 | MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page); | |
3f58a829 MK |
1108 | } |
1109 | ||
925b7673 | 1110 | void mem_cgroup_lru_del(struct page *page) |
08e552c6 | 1111 | { |
925b7673 | 1112 | mem_cgroup_lru_del_list(page, page_lru(page)); |
6d12e2d8 KH |
1113 | } |
1114 | ||
925b7673 JW |
1115 | /** |
1116 | * mem_cgroup_lru_move_lists - account for moving a page between lrus | |
1117 | * @zone: zone of the page | |
1118 | * @page: the page | |
1119 | * @from: current lru | |
1120 | * @to: target lru | |
1121 | * | |
1122 | * This function accounts for @page being moved between the lrus @from | |
1123 | * and @to, and returns the lruvec for the given @zone and the memcg | |
1124 | * @page is charged to. | |
1125 | * | |
1126 | * The callsite is then responsible for physically relinking | |
1127 | * @page->lru to the returned lruvec->lists[@to]. | |
1128 | */ | |
1129 | struct lruvec *mem_cgroup_lru_move_lists(struct zone *zone, | |
1130 | struct page *page, | |
1131 | enum lru_list from, | |
1132 | enum lru_list to) | |
66e1707b | 1133 | { |
925b7673 JW |
1134 | /* XXX: Optimize this, especially for @from == @to */ |
1135 | mem_cgroup_lru_del_list(page, from); | |
1136 | return mem_cgroup_lru_add_list(zone, page, to); | |
08e552c6 | 1137 | } |
544122e5 | 1138 | |
08e552c6 | 1139 | /* |
5a6475a4 KH |
1140 | * At handling SwapCache and other FUSE stuff, pc->mem_cgroup may be changed |
1141 | * while it's linked to lru because the page may be reused after it's fully | |
1142 | * uncharged. To handle that, unlink page_cgroup from LRU when charge it again. | |
1143 | * It's done under lock_page and expected that zone->lru_lock isnever held. | |
08e552c6 | 1144 | */ |
5a6475a4 | 1145 | static void mem_cgroup_lru_del_before_commit(struct page *page) |
08e552c6 | 1146 | { |
925b7673 | 1147 | enum lru_list lru; |
544122e5 KH |
1148 | unsigned long flags; |
1149 | struct zone *zone = page_zone(page); | |
1150 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
1151 | ||
5a6475a4 KH |
1152 | /* |
1153 | * Doing this check without taking ->lru_lock seems wrong but this | |
1154 | * is safe. Because if page_cgroup's USED bit is unset, the page | |
1155 | * will not be added to any memcg's LRU. If page_cgroup's USED bit is | |
1156 | * set, the commit after this will fail, anyway. | |
1157 | * This all charge/uncharge is done under some mutual execustion. | |
1158 | * So, we don't need to taking care of changes in USED bit. | |
1159 | */ | |
1160 | if (likely(!PageLRU(page))) | |
1161 | return; | |
1162 | ||
544122e5 | 1163 | spin_lock_irqsave(&zone->lru_lock, flags); |
925b7673 | 1164 | lru = page_lru(page); |
544122e5 | 1165 | /* |
925b7673 JW |
1166 | * The uncharged page could still be registered to the LRU of |
1167 | * the stale pc->mem_cgroup. | |
1168 | * | |
1169 | * As pc->mem_cgroup is about to get overwritten, the old LRU | |
1170 | * accounting needs to be taken care of. Let root_mem_cgroup | |
1171 | * babysit the page until the new memcg is responsible for it. | |
1172 | * | |
1173 | * The PCG_USED bit is guarded by lock_page() as the page is | |
1174 | * swapcache/pagecache. | |
544122e5 | 1175 | */ |
925b7673 JW |
1176 | if (PageLRU(page) && PageCgroupAcctLRU(pc) && !PageCgroupUsed(pc)) { |
1177 | del_page_from_lru_list(zone, page, lru); | |
1178 | add_page_to_lru_list(zone, page, lru); | |
1179 | } | |
544122e5 | 1180 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
08e552c6 KH |
1181 | } |
1182 | ||
5a6475a4 | 1183 | static void mem_cgroup_lru_add_after_commit(struct page *page) |
544122e5 | 1184 | { |
925b7673 | 1185 | enum lru_list lru; |
544122e5 KH |
1186 | unsigned long flags; |
1187 | struct zone *zone = page_zone(page); | |
1188 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
a61ed3ce JW |
1189 | /* |
1190 | * putback: charge: | |
1191 | * SetPageLRU SetPageCgroupUsed | |
1192 | * smp_mb smp_mb | |
1193 | * PageCgroupUsed && add to memcg LRU PageLRU && add to memcg LRU | |
1194 | * | |
1195 | * Ensure that one of the two sides adds the page to the memcg | |
1196 | * LRU during a race. | |
1197 | */ | |
1198 | smp_mb(); | |
5a6475a4 KH |
1199 | /* taking care of that the page is added to LRU while we commit it */ |
1200 | if (likely(!PageLRU(page))) | |
1201 | return; | |
544122e5 | 1202 | spin_lock_irqsave(&zone->lru_lock, flags); |
925b7673 JW |
1203 | lru = page_lru(page); |
1204 | /* | |
1205 | * If the page is not on the LRU, someone will soon put it | |
1206 | * there. If it is, and also already accounted for on the | |
1207 | * memcg-side, it must be on the right lruvec as setting | |
1208 | * pc->mem_cgroup and PageCgroupUsed is properly ordered. | |
1209 | * Otherwise, root_mem_cgroup has been babysitting the page | |
1210 | * during the charge. Move it to the new memcg now. | |
1211 | */ | |
1212 | if (PageLRU(page) && !PageCgroupAcctLRU(pc)) { | |
1213 | del_page_from_lru_list(zone, page, lru); | |
1214 | add_page_to_lru_list(zone, page, lru); | |
1215 | } | |
544122e5 KH |
1216 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
1217 | } | |
1218 | ||
3e92041d | 1219 | /* |
c0ff4b85 | 1220 | * Checks whether given mem is same or in the root_mem_cgroup's |
3e92041d MH |
1221 | * hierarchy subtree |
1222 | */ | |
c0ff4b85 R |
1223 | static bool mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg, |
1224 | struct mem_cgroup *memcg) | |
3e92041d | 1225 | { |
c0ff4b85 R |
1226 | if (root_memcg != memcg) { |
1227 | return (root_memcg->use_hierarchy && | |
1228 | css_is_ancestor(&memcg->css, &root_memcg->css)); | |
3e92041d MH |
1229 | } |
1230 | ||
1231 | return true; | |
1232 | } | |
1233 | ||
c0ff4b85 | 1234 | int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *memcg) |
4c4a2214 DR |
1235 | { |
1236 | int ret; | |
0b7f569e | 1237 | struct mem_cgroup *curr = NULL; |
158e0a2d | 1238 | struct task_struct *p; |
4c4a2214 | 1239 | |
158e0a2d KH |
1240 | p = find_lock_task_mm(task); |
1241 | if (!p) | |
1242 | return 0; | |
1243 | curr = try_get_mem_cgroup_from_mm(p->mm); | |
1244 | task_unlock(p); | |
0b7f569e KH |
1245 | if (!curr) |
1246 | return 0; | |
d31f56db | 1247 | /* |
c0ff4b85 | 1248 | * We should check use_hierarchy of "memcg" not "curr". Because checking |
d31f56db | 1249 | * use_hierarchy of "curr" here make this function true if hierarchy is |
c0ff4b85 R |
1250 | * enabled in "curr" and "curr" is a child of "memcg" in *cgroup* |
1251 | * hierarchy(even if use_hierarchy is disabled in "memcg"). | |
d31f56db | 1252 | */ |
c0ff4b85 | 1253 | ret = mem_cgroup_same_or_subtree(memcg, curr); |
0b7f569e | 1254 | css_put(&curr->css); |
4c4a2214 DR |
1255 | return ret; |
1256 | } | |
1257 | ||
9b272977 | 1258 | int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg, struct zone *zone) |
14797e23 | 1259 | { |
9b272977 JW |
1260 | unsigned long inactive_ratio; |
1261 | int nid = zone_to_nid(zone); | |
1262 | int zid = zone_idx(zone); | |
14797e23 | 1263 | unsigned long inactive; |
9b272977 | 1264 | unsigned long active; |
c772be93 | 1265 | unsigned long gb; |
14797e23 | 1266 | |
9b272977 JW |
1267 | inactive = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, |
1268 | BIT(LRU_INACTIVE_ANON)); | |
1269 | active = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, | |
1270 | BIT(LRU_ACTIVE_ANON)); | |
14797e23 | 1271 | |
c772be93 KM |
1272 | gb = (inactive + active) >> (30 - PAGE_SHIFT); |
1273 | if (gb) | |
1274 | inactive_ratio = int_sqrt(10 * gb); | |
1275 | else | |
1276 | inactive_ratio = 1; | |
1277 | ||
9b272977 | 1278 | return inactive * inactive_ratio < active; |
14797e23 KM |
1279 | } |
1280 | ||
9b272977 | 1281 | int mem_cgroup_inactive_file_is_low(struct mem_cgroup *memcg, struct zone *zone) |
56e49d21 RR |
1282 | { |
1283 | unsigned long active; | |
1284 | unsigned long inactive; | |
9b272977 JW |
1285 | int zid = zone_idx(zone); |
1286 | int nid = zone_to_nid(zone); | |
56e49d21 | 1287 | |
9b272977 JW |
1288 | inactive = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, |
1289 | BIT(LRU_INACTIVE_FILE)); | |
1290 | active = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, | |
1291 | BIT(LRU_ACTIVE_FILE)); | |
56e49d21 RR |
1292 | |
1293 | return (active > inactive); | |
1294 | } | |
1295 | ||
3e2f41f1 KM |
1296 | struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg, |
1297 | struct zone *zone) | |
1298 | { | |
13d7e3a2 | 1299 | int nid = zone_to_nid(zone); |
3e2f41f1 KM |
1300 | int zid = zone_idx(zone); |
1301 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
1302 | ||
1303 | return &mz->reclaim_stat; | |
1304 | } | |
1305 | ||
1306 | struct zone_reclaim_stat * | |
1307 | mem_cgroup_get_reclaim_stat_from_page(struct page *page) | |
1308 | { | |
1309 | struct page_cgroup *pc; | |
1310 | struct mem_cgroup_per_zone *mz; | |
1311 | ||
1312 | if (mem_cgroup_disabled()) | |
1313 | return NULL; | |
1314 | ||
1315 | pc = lookup_page_cgroup(page); | |
bd112db8 DN |
1316 | if (!PageCgroupUsed(pc)) |
1317 | return NULL; | |
713735b4 JW |
1318 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
1319 | smp_rmb(); | |
97a6c37b | 1320 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
3e2f41f1 KM |
1321 | return &mz->reclaim_stat; |
1322 | } | |
1323 | ||
6d61ef40 BS |
1324 | #define mem_cgroup_from_res_counter(counter, member) \ |
1325 | container_of(counter, struct mem_cgroup, member) | |
1326 | ||
19942822 | 1327 | /** |
9d11ea9f JW |
1328 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
1329 | * @mem: the memory cgroup | |
19942822 | 1330 | * |
9d11ea9f | 1331 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1332 | * pages. |
19942822 | 1333 | */ |
c0ff4b85 | 1334 | static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) |
19942822 | 1335 | { |
9d11ea9f JW |
1336 | unsigned long long margin; |
1337 | ||
c0ff4b85 | 1338 | margin = res_counter_margin(&memcg->res); |
9d11ea9f | 1339 | if (do_swap_account) |
c0ff4b85 | 1340 | margin = min(margin, res_counter_margin(&memcg->memsw)); |
7ec99d62 | 1341 | return margin >> PAGE_SHIFT; |
19942822 JW |
1342 | } |
1343 | ||
1f4c025b | 1344 | int mem_cgroup_swappiness(struct mem_cgroup *memcg) |
a7885eb8 KM |
1345 | { |
1346 | struct cgroup *cgrp = memcg->css.cgroup; | |
a7885eb8 KM |
1347 | |
1348 | /* root ? */ | |
1349 | if (cgrp->parent == NULL) | |
1350 | return vm_swappiness; | |
1351 | ||
bf1ff263 | 1352 | return memcg->swappiness; |
a7885eb8 KM |
1353 | } |
1354 | ||
c0ff4b85 | 1355 | static void mem_cgroup_start_move(struct mem_cgroup *memcg) |
32047e2a KH |
1356 | { |
1357 | int cpu; | |
1489ebad KH |
1358 | |
1359 | get_online_cpus(); | |
c0ff4b85 | 1360 | spin_lock(&memcg->pcp_counter_lock); |
1489ebad | 1361 | for_each_online_cpu(cpu) |
c0ff4b85 R |
1362 | per_cpu(memcg->stat->count[MEM_CGROUP_ON_MOVE], cpu) += 1; |
1363 | memcg->nocpu_base.count[MEM_CGROUP_ON_MOVE] += 1; | |
1364 | spin_unlock(&memcg->pcp_counter_lock); | |
1489ebad | 1365 | put_online_cpus(); |
32047e2a KH |
1366 | |
1367 | synchronize_rcu(); | |
1368 | } | |
1369 | ||
c0ff4b85 | 1370 | static void mem_cgroup_end_move(struct mem_cgroup *memcg) |
32047e2a KH |
1371 | { |
1372 | int cpu; | |
1373 | ||
c0ff4b85 | 1374 | if (!memcg) |
32047e2a | 1375 | return; |
1489ebad | 1376 | get_online_cpus(); |
c0ff4b85 | 1377 | spin_lock(&memcg->pcp_counter_lock); |
1489ebad | 1378 | for_each_online_cpu(cpu) |
c0ff4b85 R |
1379 | per_cpu(memcg->stat->count[MEM_CGROUP_ON_MOVE], cpu) -= 1; |
1380 | memcg->nocpu_base.count[MEM_CGROUP_ON_MOVE] -= 1; | |
1381 | spin_unlock(&memcg->pcp_counter_lock); | |
1489ebad | 1382 | put_online_cpus(); |
32047e2a KH |
1383 | } |
1384 | /* | |
1385 | * 2 routines for checking "mem" is under move_account() or not. | |
1386 | * | |
1387 | * mem_cgroup_stealed() - checking a cgroup is mc.from or not. This is used | |
1388 | * for avoiding race in accounting. If true, | |
1389 | * pc->mem_cgroup may be overwritten. | |
1390 | * | |
1391 | * mem_cgroup_under_move() - checking a cgroup is mc.from or mc.to or | |
1392 | * under hierarchy of moving cgroups. This is for | |
1393 | * waiting at hith-memory prressure caused by "move". | |
1394 | */ | |
1395 | ||
c0ff4b85 | 1396 | static bool mem_cgroup_stealed(struct mem_cgroup *memcg) |
32047e2a KH |
1397 | { |
1398 | VM_BUG_ON(!rcu_read_lock_held()); | |
c0ff4b85 | 1399 | return this_cpu_read(memcg->stat->count[MEM_CGROUP_ON_MOVE]) > 0; |
32047e2a | 1400 | } |
4b534334 | 1401 | |
c0ff4b85 | 1402 | static bool mem_cgroup_under_move(struct mem_cgroup *memcg) |
4b534334 | 1403 | { |
2bd9bb20 KH |
1404 | struct mem_cgroup *from; |
1405 | struct mem_cgroup *to; | |
4b534334 | 1406 | bool ret = false; |
2bd9bb20 KH |
1407 | /* |
1408 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1409 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1410 | */ | |
1411 | spin_lock(&mc.lock); | |
1412 | from = mc.from; | |
1413 | to = mc.to; | |
1414 | if (!from) | |
1415 | goto unlock; | |
3e92041d | 1416 | |
c0ff4b85 R |
1417 | ret = mem_cgroup_same_or_subtree(memcg, from) |
1418 | || mem_cgroup_same_or_subtree(memcg, to); | |
2bd9bb20 KH |
1419 | unlock: |
1420 | spin_unlock(&mc.lock); | |
4b534334 KH |
1421 | return ret; |
1422 | } | |
1423 | ||
c0ff4b85 | 1424 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) |
4b534334 KH |
1425 | { |
1426 | if (mc.moving_task && current != mc.moving_task) { | |
c0ff4b85 | 1427 | if (mem_cgroup_under_move(memcg)) { |
4b534334 KH |
1428 | DEFINE_WAIT(wait); |
1429 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1430 | /* moving charge context might have finished. */ | |
1431 | if (mc.moving_task) | |
1432 | schedule(); | |
1433 | finish_wait(&mc.waitq, &wait); | |
1434 | return true; | |
1435 | } | |
1436 | } | |
1437 | return false; | |
1438 | } | |
1439 | ||
e222432b | 1440 | /** |
6a6135b6 | 1441 | * mem_cgroup_print_oom_info: Called from OOM with tasklist_lock held in read mode. |
e222432b BS |
1442 | * @memcg: The memory cgroup that went over limit |
1443 | * @p: Task that is going to be killed | |
1444 | * | |
1445 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1446 | * enabled | |
1447 | */ | |
1448 | void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) | |
1449 | { | |
1450 | struct cgroup *task_cgrp; | |
1451 | struct cgroup *mem_cgrp; | |
1452 | /* | |
1453 | * Need a buffer in BSS, can't rely on allocations. The code relies | |
1454 | * on the assumption that OOM is serialized for memory controller. | |
1455 | * If this assumption is broken, revisit this code. | |
1456 | */ | |
1457 | static char memcg_name[PATH_MAX]; | |
1458 | int ret; | |
1459 | ||
d31f56db | 1460 | if (!memcg || !p) |
e222432b BS |
1461 | return; |
1462 | ||
1463 | ||
1464 | rcu_read_lock(); | |
1465 | ||
1466 | mem_cgrp = memcg->css.cgroup; | |
1467 | task_cgrp = task_cgroup(p, mem_cgroup_subsys_id); | |
1468 | ||
1469 | ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX); | |
1470 | if (ret < 0) { | |
1471 | /* | |
1472 | * Unfortunately, we are unable to convert to a useful name | |
1473 | * But we'll still print out the usage information | |
1474 | */ | |
1475 | rcu_read_unlock(); | |
1476 | goto done; | |
1477 | } | |
1478 | rcu_read_unlock(); | |
1479 | ||
1480 | printk(KERN_INFO "Task in %s killed", memcg_name); | |
1481 | ||
1482 | rcu_read_lock(); | |
1483 | ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX); | |
1484 | if (ret < 0) { | |
1485 | rcu_read_unlock(); | |
1486 | goto done; | |
1487 | } | |
1488 | rcu_read_unlock(); | |
1489 | ||
1490 | /* | |
1491 | * Continues from above, so we don't need an KERN_ level | |
1492 | */ | |
1493 | printk(KERN_CONT " as a result of limit of %s\n", memcg_name); | |
1494 | done: | |
1495 | ||
1496 | printk(KERN_INFO "memory: usage %llukB, limit %llukB, failcnt %llu\n", | |
1497 | res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, | |
1498 | res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, | |
1499 | res_counter_read_u64(&memcg->res, RES_FAILCNT)); | |
1500 | printk(KERN_INFO "memory+swap: usage %llukB, limit %llukB, " | |
1501 | "failcnt %llu\n", | |
1502 | res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, | |
1503 | res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, | |
1504 | res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); | |
1505 | } | |
1506 | ||
81d39c20 KH |
1507 | /* |
1508 | * This function returns the number of memcg under hierarchy tree. Returns | |
1509 | * 1(self count) if no children. | |
1510 | */ | |
c0ff4b85 | 1511 | static int mem_cgroup_count_children(struct mem_cgroup *memcg) |
81d39c20 KH |
1512 | { |
1513 | int num = 0; | |
7d74b06f KH |
1514 | struct mem_cgroup *iter; |
1515 | ||
c0ff4b85 | 1516 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 1517 | num++; |
81d39c20 KH |
1518 | return num; |
1519 | } | |
1520 | ||
a63d83f4 DR |
1521 | /* |
1522 | * Return the memory (and swap, if configured) limit for a memcg. | |
1523 | */ | |
1524 | u64 mem_cgroup_get_limit(struct mem_cgroup *memcg) | |
1525 | { | |
1526 | u64 limit; | |
1527 | u64 memsw; | |
1528 | ||
f3e8eb70 JW |
1529 | limit = res_counter_read_u64(&memcg->res, RES_LIMIT); |
1530 | limit += total_swap_pages << PAGE_SHIFT; | |
1531 | ||
a63d83f4 DR |
1532 | memsw = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
1533 | /* | |
1534 | * If memsw is finite and limits the amount of swap space available | |
1535 | * to this memcg, return that limit. | |
1536 | */ | |
1537 | return min(limit, memsw); | |
1538 | } | |
1539 | ||
5660048c JW |
1540 | static unsigned long mem_cgroup_reclaim(struct mem_cgroup *memcg, |
1541 | gfp_t gfp_mask, | |
1542 | unsigned long flags) | |
1543 | { | |
1544 | unsigned long total = 0; | |
1545 | bool noswap = false; | |
1546 | int loop; | |
1547 | ||
1548 | if (flags & MEM_CGROUP_RECLAIM_NOSWAP) | |
1549 | noswap = true; | |
1550 | if (!(flags & MEM_CGROUP_RECLAIM_SHRINK) && memcg->memsw_is_minimum) | |
1551 | noswap = true; | |
1552 | ||
1553 | for (loop = 0; loop < MEM_CGROUP_MAX_RECLAIM_LOOPS; loop++) { | |
1554 | if (loop) | |
1555 | drain_all_stock_async(memcg); | |
1556 | total += try_to_free_mem_cgroup_pages(memcg, gfp_mask, noswap); | |
1557 | /* | |
1558 | * Allow limit shrinkers, which are triggered directly | |
1559 | * by userspace, to catch signals and stop reclaim | |
1560 | * after minimal progress, regardless of the margin. | |
1561 | */ | |
1562 | if (total && (flags & MEM_CGROUP_RECLAIM_SHRINK)) | |
1563 | break; | |
1564 | if (mem_cgroup_margin(memcg)) | |
1565 | break; | |
1566 | /* | |
1567 | * If nothing was reclaimed after two attempts, there | |
1568 | * may be no reclaimable pages in this hierarchy. | |
1569 | */ | |
1570 | if (loop && !total) | |
1571 | break; | |
1572 | } | |
1573 | return total; | |
1574 | } | |
1575 | ||
4d0c066d KH |
1576 | /** |
1577 | * test_mem_cgroup_node_reclaimable | |
1578 | * @mem: the target memcg | |
1579 | * @nid: the node ID to be checked. | |
1580 | * @noswap : specify true here if the user wants flle only information. | |
1581 | * | |
1582 | * This function returns whether the specified memcg contains any | |
1583 | * reclaimable pages on a node. Returns true if there are any reclaimable | |
1584 | * pages in the node. | |
1585 | */ | |
c0ff4b85 | 1586 | static bool test_mem_cgroup_node_reclaimable(struct mem_cgroup *memcg, |
4d0c066d KH |
1587 | int nid, bool noswap) |
1588 | { | |
c0ff4b85 | 1589 | if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_FILE)) |
4d0c066d KH |
1590 | return true; |
1591 | if (noswap || !total_swap_pages) | |
1592 | return false; | |
c0ff4b85 | 1593 | if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_ANON)) |
4d0c066d KH |
1594 | return true; |
1595 | return false; | |
1596 | ||
1597 | } | |
889976db YH |
1598 | #if MAX_NUMNODES > 1 |
1599 | ||
1600 | /* | |
1601 | * Always updating the nodemask is not very good - even if we have an empty | |
1602 | * list or the wrong list here, we can start from some node and traverse all | |
1603 | * nodes based on the zonelist. So update the list loosely once per 10 secs. | |
1604 | * | |
1605 | */ | |
c0ff4b85 | 1606 | static void mem_cgroup_may_update_nodemask(struct mem_cgroup *memcg) |
889976db YH |
1607 | { |
1608 | int nid; | |
453a9bf3 KH |
1609 | /* |
1610 | * numainfo_events > 0 means there was at least NUMAINFO_EVENTS_TARGET | |
1611 | * pagein/pageout changes since the last update. | |
1612 | */ | |
c0ff4b85 | 1613 | if (!atomic_read(&memcg->numainfo_events)) |
453a9bf3 | 1614 | return; |
c0ff4b85 | 1615 | if (atomic_inc_return(&memcg->numainfo_updating) > 1) |
889976db YH |
1616 | return; |
1617 | ||
889976db | 1618 | /* make a nodemask where this memcg uses memory from */ |
c0ff4b85 | 1619 | memcg->scan_nodes = node_states[N_HIGH_MEMORY]; |
889976db YH |
1620 | |
1621 | for_each_node_mask(nid, node_states[N_HIGH_MEMORY]) { | |
1622 | ||
c0ff4b85 R |
1623 | if (!test_mem_cgroup_node_reclaimable(memcg, nid, false)) |
1624 | node_clear(nid, memcg->scan_nodes); | |
889976db | 1625 | } |
453a9bf3 | 1626 | |
c0ff4b85 R |
1627 | atomic_set(&memcg->numainfo_events, 0); |
1628 | atomic_set(&memcg->numainfo_updating, 0); | |
889976db YH |
1629 | } |
1630 | ||
1631 | /* | |
1632 | * Selecting a node where we start reclaim from. Because what we need is just | |
1633 | * reducing usage counter, start from anywhere is O,K. Considering | |
1634 | * memory reclaim from current node, there are pros. and cons. | |
1635 | * | |
1636 | * Freeing memory from current node means freeing memory from a node which | |
1637 | * we'll use or we've used. So, it may make LRU bad. And if several threads | |
1638 | * hit limits, it will see a contention on a node. But freeing from remote | |
1639 | * node means more costs for memory reclaim because of memory latency. | |
1640 | * | |
1641 | * Now, we use round-robin. Better algorithm is welcomed. | |
1642 | */ | |
c0ff4b85 | 1643 | int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) |
889976db YH |
1644 | { |
1645 | int node; | |
1646 | ||
c0ff4b85 R |
1647 | mem_cgroup_may_update_nodemask(memcg); |
1648 | node = memcg->last_scanned_node; | |
889976db | 1649 | |
c0ff4b85 | 1650 | node = next_node(node, memcg->scan_nodes); |
889976db | 1651 | if (node == MAX_NUMNODES) |
c0ff4b85 | 1652 | node = first_node(memcg->scan_nodes); |
889976db YH |
1653 | /* |
1654 | * We call this when we hit limit, not when pages are added to LRU. | |
1655 | * No LRU may hold pages because all pages are UNEVICTABLE or | |
1656 | * memcg is too small and all pages are not on LRU. In that case, | |
1657 | * we use curret node. | |
1658 | */ | |
1659 | if (unlikely(node == MAX_NUMNODES)) | |
1660 | node = numa_node_id(); | |
1661 | ||
c0ff4b85 | 1662 | memcg->last_scanned_node = node; |
889976db YH |
1663 | return node; |
1664 | } | |
1665 | ||
4d0c066d KH |
1666 | /* |
1667 | * Check all nodes whether it contains reclaimable pages or not. | |
1668 | * For quick scan, we make use of scan_nodes. This will allow us to skip | |
1669 | * unused nodes. But scan_nodes is lazily updated and may not cotain | |
1670 | * enough new information. We need to do double check. | |
1671 | */ | |
c0ff4b85 | 1672 | bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) |
4d0c066d KH |
1673 | { |
1674 | int nid; | |
1675 | ||
1676 | /* | |
1677 | * quick check...making use of scan_node. | |
1678 | * We can skip unused nodes. | |
1679 | */ | |
c0ff4b85 R |
1680 | if (!nodes_empty(memcg->scan_nodes)) { |
1681 | for (nid = first_node(memcg->scan_nodes); | |
4d0c066d | 1682 | nid < MAX_NUMNODES; |
c0ff4b85 | 1683 | nid = next_node(nid, memcg->scan_nodes)) { |
4d0c066d | 1684 | |
c0ff4b85 | 1685 | if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap)) |
4d0c066d KH |
1686 | return true; |
1687 | } | |
1688 | } | |
1689 | /* | |
1690 | * Check rest of nodes. | |
1691 | */ | |
1692 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
c0ff4b85 | 1693 | if (node_isset(nid, memcg->scan_nodes)) |
4d0c066d | 1694 | continue; |
c0ff4b85 | 1695 | if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap)) |
4d0c066d KH |
1696 | return true; |
1697 | } | |
1698 | return false; | |
1699 | } | |
1700 | ||
889976db | 1701 | #else |
c0ff4b85 | 1702 | int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) |
889976db YH |
1703 | { |
1704 | return 0; | |
1705 | } | |
4d0c066d | 1706 | |
c0ff4b85 | 1707 | bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) |
4d0c066d | 1708 | { |
c0ff4b85 | 1709 | return test_mem_cgroup_node_reclaimable(memcg, 0, noswap); |
4d0c066d | 1710 | } |
889976db YH |
1711 | #endif |
1712 | ||
5660048c JW |
1713 | static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, |
1714 | struct zone *zone, | |
1715 | gfp_t gfp_mask, | |
1716 | unsigned long *total_scanned) | |
6d61ef40 | 1717 | { |
9f3a0d09 | 1718 | struct mem_cgroup *victim = NULL; |
5660048c | 1719 | int total = 0; |
04046e1a | 1720 | int loop = 0; |
9d11ea9f | 1721 | unsigned long excess; |
185efc0f | 1722 | unsigned long nr_scanned; |
527a5ec9 JW |
1723 | struct mem_cgroup_reclaim_cookie reclaim = { |
1724 | .zone = zone, | |
1725 | .priority = 0, | |
1726 | }; | |
9d11ea9f | 1727 | |
c0ff4b85 | 1728 | excess = res_counter_soft_limit_excess(&root_memcg->res) >> PAGE_SHIFT; |
04046e1a | 1729 | |
4e416953 | 1730 | while (1) { |
527a5ec9 | 1731 | victim = mem_cgroup_iter(root_memcg, victim, &reclaim); |
9f3a0d09 | 1732 | if (!victim) { |
04046e1a | 1733 | loop++; |
4e416953 BS |
1734 | if (loop >= 2) { |
1735 | /* | |
1736 | * If we have not been able to reclaim | |
1737 | * anything, it might because there are | |
1738 | * no reclaimable pages under this hierarchy | |
1739 | */ | |
5660048c | 1740 | if (!total) |
4e416953 | 1741 | break; |
4e416953 | 1742 | /* |
25985edc | 1743 | * We want to do more targeted reclaim. |
4e416953 BS |
1744 | * excess >> 2 is not to excessive so as to |
1745 | * reclaim too much, nor too less that we keep | |
1746 | * coming back to reclaim from this cgroup | |
1747 | */ | |
1748 | if (total >= (excess >> 2) || | |
9f3a0d09 | 1749 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) |
4e416953 | 1750 | break; |
4e416953 | 1751 | } |
9f3a0d09 | 1752 | continue; |
4e416953 | 1753 | } |
5660048c | 1754 | if (!mem_cgroup_reclaimable(victim, false)) |
6d61ef40 | 1755 | continue; |
5660048c JW |
1756 | total += mem_cgroup_shrink_node_zone(victim, gfp_mask, false, |
1757 | zone, &nr_scanned); | |
1758 | *total_scanned += nr_scanned; | |
1759 | if (!res_counter_soft_limit_excess(&root_memcg->res)) | |
9f3a0d09 | 1760 | break; |
6d61ef40 | 1761 | } |
9f3a0d09 | 1762 | mem_cgroup_iter_break(root_memcg, victim); |
04046e1a | 1763 | return total; |
6d61ef40 BS |
1764 | } |
1765 | ||
867578cb KH |
1766 | /* |
1767 | * Check OOM-Killer is already running under our hierarchy. | |
1768 | * If someone is running, return false. | |
1af8efe9 | 1769 | * Has to be called with memcg_oom_lock |
867578cb | 1770 | */ |
c0ff4b85 | 1771 | static bool mem_cgroup_oom_lock(struct mem_cgroup *memcg) |
867578cb | 1772 | { |
79dfdacc | 1773 | struct mem_cgroup *iter, *failed = NULL; |
a636b327 | 1774 | |
9f3a0d09 | 1775 | for_each_mem_cgroup_tree(iter, memcg) { |
23751be0 | 1776 | if (iter->oom_lock) { |
79dfdacc MH |
1777 | /* |
1778 | * this subtree of our hierarchy is already locked | |
1779 | * so we cannot give a lock. | |
1780 | */ | |
79dfdacc | 1781 | failed = iter; |
9f3a0d09 JW |
1782 | mem_cgroup_iter_break(memcg, iter); |
1783 | break; | |
23751be0 JW |
1784 | } else |
1785 | iter->oom_lock = true; | |
7d74b06f | 1786 | } |
867578cb | 1787 | |
79dfdacc | 1788 | if (!failed) |
23751be0 | 1789 | return true; |
79dfdacc MH |
1790 | |
1791 | /* | |
1792 | * OK, we failed to lock the whole subtree so we have to clean up | |
1793 | * what we set up to the failing subtree | |
1794 | */ | |
9f3a0d09 | 1795 | for_each_mem_cgroup_tree(iter, memcg) { |
79dfdacc | 1796 | if (iter == failed) { |
9f3a0d09 JW |
1797 | mem_cgroup_iter_break(memcg, iter); |
1798 | break; | |
79dfdacc MH |
1799 | } |
1800 | iter->oom_lock = false; | |
1801 | } | |
23751be0 | 1802 | return false; |
a636b327 | 1803 | } |
0b7f569e | 1804 | |
79dfdacc | 1805 | /* |
1af8efe9 | 1806 | * Has to be called with memcg_oom_lock |
79dfdacc | 1807 | */ |
c0ff4b85 | 1808 | static int mem_cgroup_oom_unlock(struct mem_cgroup *memcg) |
0b7f569e | 1809 | { |
7d74b06f KH |
1810 | struct mem_cgroup *iter; |
1811 | ||
c0ff4b85 | 1812 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc MH |
1813 | iter->oom_lock = false; |
1814 | return 0; | |
1815 | } | |
1816 | ||
c0ff4b85 | 1817 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1818 | { |
1819 | struct mem_cgroup *iter; | |
1820 | ||
c0ff4b85 | 1821 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc MH |
1822 | atomic_inc(&iter->under_oom); |
1823 | } | |
1824 | ||
c0ff4b85 | 1825 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1826 | { |
1827 | struct mem_cgroup *iter; | |
1828 | ||
867578cb KH |
1829 | /* |
1830 | * When a new child is created while the hierarchy is under oom, | |
1831 | * mem_cgroup_oom_lock() may not be called. We have to use | |
1832 | * atomic_add_unless() here. | |
1833 | */ | |
c0ff4b85 | 1834 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc | 1835 | atomic_add_unless(&iter->under_oom, -1, 0); |
0b7f569e KH |
1836 | } |
1837 | ||
1af8efe9 | 1838 | static DEFINE_SPINLOCK(memcg_oom_lock); |
867578cb KH |
1839 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1840 | ||
dc98df5a KH |
1841 | struct oom_wait_info { |
1842 | struct mem_cgroup *mem; | |
1843 | wait_queue_t wait; | |
1844 | }; | |
1845 | ||
1846 | static int memcg_oom_wake_function(wait_queue_t *wait, | |
1847 | unsigned mode, int sync, void *arg) | |
1848 | { | |
c0ff4b85 R |
1849 | struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg, |
1850 | *oom_wait_memcg; | |
dc98df5a KH |
1851 | struct oom_wait_info *oom_wait_info; |
1852 | ||
1853 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
c0ff4b85 | 1854 | oom_wait_memcg = oom_wait_info->mem; |
dc98df5a | 1855 | |
dc98df5a KH |
1856 | /* |
1857 | * Both of oom_wait_info->mem and wake_mem are stable under us. | |
1858 | * Then we can use css_is_ancestor without taking care of RCU. | |
1859 | */ | |
c0ff4b85 R |
1860 | if (!mem_cgroup_same_or_subtree(oom_wait_memcg, wake_memcg) |
1861 | && !mem_cgroup_same_or_subtree(wake_memcg, oom_wait_memcg)) | |
dc98df5a | 1862 | return 0; |
dc98df5a KH |
1863 | return autoremove_wake_function(wait, mode, sync, arg); |
1864 | } | |
1865 | ||
c0ff4b85 | 1866 | static void memcg_wakeup_oom(struct mem_cgroup *memcg) |
dc98df5a | 1867 | { |
c0ff4b85 R |
1868 | /* for filtering, pass "memcg" as argument. */ |
1869 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg); | |
dc98df5a KH |
1870 | } |
1871 | ||
c0ff4b85 | 1872 | static void memcg_oom_recover(struct mem_cgroup *memcg) |
3c11ecf4 | 1873 | { |
c0ff4b85 R |
1874 | if (memcg && atomic_read(&memcg->under_oom)) |
1875 | memcg_wakeup_oom(memcg); | |
3c11ecf4 KH |
1876 | } |
1877 | ||
867578cb KH |
1878 | /* |
1879 | * try to call OOM killer. returns false if we should exit memory-reclaim loop. | |
1880 | */ | |
c0ff4b85 | 1881 | bool mem_cgroup_handle_oom(struct mem_cgroup *memcg, gfp_t mask) |
0b7f569e | 1882 | { |
dc98df5a | 1883 | struct oom_wait_info owait; |
3c11ecf4 | 1884 | bool locked, need_to_kill; |
867578cb | 1885 | |
c0ff4b85 | 1886 | owait.mem = memcg; |
dc98df5a KH |
1887 | owait.wait.flags = 0; |
1888 | owait.wait.func = memcg_oom_wake_function; | |
1889 | owait.wait.private = current; | |
1890 | INIT_LIST_HEAD(&owait.wait.task_list); | |
3c11ecf4 | 1891 | need_to_kill = true; |
c0ff4b85 | 1892 | mem_cgroup_mark_under_oom(memcg); |
79dfdacc | 1893 | |
c0ff4b85 | 1894 | /* At first, try to OOM lock hierarchy under memcg.*/ |
1af8efe9 | 1895 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1896 | locked = mem_cgroup_oom_lock(memcg); |
867578cb KH |
1897 | /* |
1898 | * Even if signal_pending(), we can't quit charge() loop without | |
1899 | * accounting. So, UNINTERRUPTIBLE is appropriate. But SIGKILL | |
1900 | * under OOM is always welcomed, use TASK_KILLABLE here. | |
1901 | */ | |
3c11ecf4 | 1902 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
c0ff4b85 | 1903 | if (!locked || memcg->oom_kill_disable) |
3c11ecf4 KH |
1904 | need_to_kill = false; |
1905 | if (locked) | |
c0ff4b85 | 1906 | mem_cgroup_oom_notify(memcg); |
1af8efe9 | 1907 | spin_unlock(&memcg_oom_lock); |
867578cb | 1908 | |
3c11ecf4 KH |
1909 | if (need_to_kill) { |
1910 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
c0ff4b85 | 1911 | mem_cgroup_out_of_memory(memcg, mask); |
3c11ecf4 | 1912 | } else { |
867578cb | 1913 | schedule(); |
dc98df5a | 1914 | finish_wait(&memcg_oom_waitq, &owait.wait); |
867578cb | 1915 | } |
1af8efe9 | 1916 | spin_lock(&memcg_oom_lock); |
79dfdacc | 1917 | if (locked) |
c0ff4b85 R |
1918 | mem_cgroup_oom_unlock(memcg); |
1919 | memcg_wakeup_oom(memcg); | |
1af8efe9 | 1920 | spin_unlock(&memcg_oom_lock); |
867578cb | 1921 | |
c0ff4b85 | 1922 | mem_cgroup_unmark_under_oom(memcg); |
79dfdacc | 1923 | |
867578cb KH |
1924 | if (test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current)) |
1925 | return false; | |
1926 | /* Give chance to dying process */ | |
715a5ee8 | 1927 | schedule_timeout_uninterruptible(1); |
867578cb | 1928 | return true; |
0b7f569e KH |
1929 | } |
1930 | ||
d69b042f BS |
1931 | /* |
1932 | * Currently used to update mapped file statistics, but the routine can be | |
1933 | * generalized to update other statistics as well. | |
32047e2a KH |
1934 | * |
1935 | * Notes: Race condition | |
1936 | * | |
1937 | * We usually use page_cgroup_lock() for accessing page_cgroup member but | |
1938 | * it tends to be costly. But considering some conditions, we doesn't need | |
1939 | * to do so _always_. | |
1940 | * | |
1941 | * Considering "charge", lock_page_cgroup() is not required because all | |
1942 | * file-stat operations happen after a page is attached to radix-tree. There | |
1943 | * are no race with "charge". | |
1944 | * | |
1945 | * Considering "uncharge", we know that memcg doesn't clear pc->mem_cgroup | |
1946 | * at "uncharge" intentionally. So, we always see valid pc->mem_cgroup even | |
1947 | * if there are race with "uncharge". Statistics itself is properly handled | |
1948 | * by flags. | |
1949 | * | |
1950 | * Considering "move", this is an only case we see a race. To make the race | |
1951 | * small, we check MEM_CGROUP_ON_MOVE percpu value and detect there are | |
1952 | * possibility of race condition. If there is, we take a lock. | |
d69b042f | 1953 | */ |
26174efd | 1954 | |
2a7106f2 GT |
1955 | void mem_cgroup_update_page_stat(struct page *page, |
1956 | enum mem_cgroup_page_stat_item idx, int val) | |
d69b042f | 1957 | { |
c0ff4b85 | 1958 | struct mem_cgroup *memcg; |
32047e2a KH |
1959 | struct page_cgroup *pc = lookup_page_cgroup(page); |
1960 | bool need_unlock = false; | |
dbd4ea78 | 1961 | unsigned long uninitialized_var(flags); |
d69b042f | 1962 | |
d69b042f BS |
1963 | if (unlikely(!pc)) |
1964 | return; | |
1965 | ||
32047e2a | 1966 | rcu_read_lock(); |
c0ff4b85 R |
1967 | memcg = pc->mem_cgroup; |
1968 | if (unlikely(!memcg || !PageCgroupUsed(pc))) | |
32047e2a KH |
1969 | goto out; |
1970 | /* pc->mem_cgroup is unstable ? */ | |
c0ff4b85 | 1971 | if (unlikely(mem_cgroup_stealed(memcg)) || PageTransHuge(page)) { |
32047e2a | 1972 | /* take a lock against to access pc->mem_cgroup */ |
dbd4ea78 | 1973 | move_lock_page_cgroup(pc, &flags); |
32047e2a | 1974 | need_unlock = true; |
c0ff4b85 R |
1975 | memcg = pc->mem_cgroup; |
1976 | if (!memcg || !PageCgroupUsed(pc)) | |
32047e2a KH |
1977 | goto out; |
1978 | } | |
26174efd | 1979 | |
26174efd | 1980 | switch (idx) { |
2a7106f2 | 1981 | case MEMCG_NR_FILE_MAPPED: |
26174efd KH |
1982 | if (val > 0) |
1983 | SetPageCgroupFileMapped(pc); | |
1984 | else if (!page_mapped(page)) | |
0c270f8f | 1985 | ClearPageCgroupFileMapped(pc); |
2a7106f2 | 1986 | idx = MEM_CGROUP_STAT_FILE_MAPPED; |
26174efd KH |
1987 | break; |
1988 | default: | |
1989 | BUG(); | |
8725d541 | 1990 | } |
d69b042f | 1991 | |
c0ff4b85 | 1992 | this_cpu_add(memcg->stat->count[idx], val); |
2a7106f2 | 1993 | |
32047e2a KH |
1994 | out: |
1995 | if (unlikely(need_unlock)) | |
dbd4ea78 | 1996 | move_unlock_page_cgroup(pc, &flags); |
32047e2a KH |
1997 | rcu_read_unlock(); |
1998 | return; | |
d69b042f | 1999 | } |
2a7106f2 | 2000 | EXPORT_SYMBOL(mem_cgroup_update_page_stat); |
26174efd | 2001 | |
cdec2e42 KH |
2002 | /* |
2003 | * size of first charge trial. "32" comes from vmscan.c's magic value. | |
2004 | * TODO: maybe necessary to use big numbers in big irons. | |
2005 | */ | |
7ec99d62 | 2006 | #define CHARGE_BATCH 32U |
cdec2e42 KH |
2007 | struct memcg_stock_pcp { |
2008 | struct mem_cgroup *cached; /* this never be root cgroup */ | |
11c9ea4e | 2009 | unsigned int nr_pages; |
cdec2e42 | 2010 | struct work_struct work; |
26fe6168 KH |
2011 | unsigned long flags; |
2012 | #define FLUSHING_CACHED_CHARGE (0) | |
cdec2e42 KH |
2013 | }; |
2014 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); | |
9f50fad6 | 2015 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 KH |
2016 | |
2017 | /* | |
11c9ea4e | 2018 | * Try to consume stocked charge on this cpu. If success, one page is consumed |
cdec2e42 KH |
2019 | * from local stock and true is returned. If the stock is 0 or charges from a |
2020 | * cgroup which is not current target, returns false. This stock will be | |
2021 | * refilled. | |
2022 | */ | |
c0ff4b85 | 2023 | static bool consume_stock(struct mem_cgroup *memcg) |
cdec2e42 KH |
2024 | { |
2025 | struct memcg_stock_pcp *stock; | |
2026 | bool ret = true; | |
2027 | ||
2028 | stock = &get_cpu_var(memcg_stock); | |
c0ff4b85 | 2029 | if (memcg == stock->cached && stock->nr_pages) |
11c9ea4e | 2030 | stock->nr_pages--; |
cdec2e42 KH |
2031 | else /* need to call res_counter_charge */ |
2032 | ret = false; | |
2033 | put_cpu_var(memcg_stock); | |
2034 | return ret; | |
2035 | } | |
2036 | ||
2037 | /* | |
2038 | * Returns stocks cached in percpu to res_counter and reset cached information. | |
2039 | */ | |
2040 | static void drain_stock(struct memcg_stock_pcp *stock) | |
2041 | { | |
2042 | struct mem_cgroup *old = stock->cached; | |
2043 | ||
11c9ea4e JW |
2044 | if (stock->nr_pages) { |
2045 | unsigned long bytes = stock->nr_pages * PAGE_SIZE; | |
2046 | ||
2047 | res_counter_uncharge(&old->res, bytes); | |
cdec2e42 | 2048 | if (do_swap_account) |
11c9ea4e JW |
2049 | res_counter_uncharge(&old->memsw, bytes); |
2050 | stock->nr_pages = 0; | |
cdec2e42 KH |
2051 | } |
2052 | stock->cached = NULL; | |
cdec2e42 KH |
2053 | } |
2054 | ||
2055 | /* | |
2056 | * This must be called under preempt disabled or must be called by | |
2057 | * a thread which is pinned to local cpu. | |
2058 | */ | |
2059 | static void drain_local_stock(struct work_struct *dummy) | |
2060 | { | |
2061 | struct memcg_stock_pcp *stock = &__get_cpu_var(memcg_stock); | |
2062 | drain_stock(stock); | |
26fe6168 | 2063 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
cdec2e42 KH |
2064 | } |
2065 | ||
2066 | /* | |
2067 | * Cache charges(val) which is from res_counter, to local per_cpu area. | |
320cc51d | 2068 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 2069 | */ |
c0ff4b85 | 2070 | static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
2071 | { |
2072 | struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock); | |
2073 | ||
c0ff4b85 | 2074 | if (stock->cached != memcg) { /* reset if necessary */ |
cdec2e42 | 2075 | drain_stock(stock); |
c0ff4b85 | 2076 | stock->cached = memcg; |
cdec2e42 | 2077 | } |
11c9ea4e | 2078 | stock->nr_pages += nr_pages; |
cdec2e42 KH |
2079 | put_cpu_var(memcg_stock); |
2080 | } | |
2081 | ||
2082 | /* | |
c0ff4b85 | 2083 | * Drains all per-CPU charge caches for given root_memcg resp. subtree |
d38144b7 MH |
2084 | * of the hierarchy under it. sync flag says whether we should block |
2085 | * until the work is done. | |
cdec2e42 | 2086 | */ |
c0ff4b85 | 2087 | static void drain_all_stock(struct mem_cgroup *root_memcg, bool sync) |
cdec2e42 | 2088 | { |
26fe6168 | 2089 | int cpu, curcpu; |
d38144b7 | 2090 | |
cdec2e42 | 2091 | /* Notify other cpus that system-wide "drain" is running */ |
cdec2e42 | 2092 | get_online_cpus(); |
5af12d0e | 2093 | curcpu = get_cpu(); |
cdec2e42 KH |
2094 | for_each_online_cpu(cpu) { |
2095 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
c0ff4b85 | 2096 | struct mem_cgroup *memcg; |
26fe6168 | 2097 | |
c0ff4b85 R |
2098 | memcg = stock->cached; |
2099 | if (!memcg || !stock->nr_pages) | |
26fe6168 | 2100 | continue; |
c0ff4b85 | 2101 | if (!mem_cgroup_same_or_subtree(root_memcg, memcg)) |
3e92041d | 2102 | continue; |
d1a05b69 MH |
2103 | if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { |
2104 | if (cpu == curcpu) | |
2105 | drain_local_stock(&stock->work); | |
2106 | else | |
2107 | schedule_work_on(cpu, &stock->work); | |
2108 | } | |
cdec2e42 | 2109 | } |
5af12d0e | 2110 | put_cpu(); |
d38144b7 MH |
2111 | |
2112 | if (!sync) | |
2113 | goto out; | |
2114 | ||
2115 | for_each_online_cpu(cpu) { | |
2116 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
9f50fad6 | 2117 | if (test_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) |
d38144b7 MH |
2118 | flush_work(&stock->work); |
2119 | } | |
2120 | out: | |
cdec2e42 | 2121 | put_online_cpus(); |
d38144b7 MH |
2122 | } |
2123 | ||
2124 | /* | |
2125 | * Tries to drain stocked charges in other cpus. This function is asynchronous | |
2126 | * and just put a work per cpu for draining localy on each cpu. Caller can | |
2127 | * expects some charges will be back to res_counter later but cannot wait for | |
2128 | * it. | |
2129 | */ | |
c0ff4b85 | 2130 | static void drain_all_stock_async(struct mem_cgroup *root_memcg) |
d38144b7 | 2131 | { |
9f50fad6 MH |
2132 | /* |
2133 | * If someone calls draining, avoid adding more kworker runs. | |
2134 | */ | |
2135 | if (!mutex_trylock(&percpu_charge_mutex)) | |
2136 | return; | |
c0ff4b85 | 2137 | drain_all_stock(root_memcg, false); |
9f50fad6 | 2138 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2139 | } |
2140 | ||
2141 | /* This is a synchronous drain interface. */ | |
c0ff4b85 | 2142 | static void drain_all_stock_sync(struct mem_cgroup *root_memcg) |
cdec2e42 KH |
2143 | { |
2144 | /* called when force_empty is called */ | |
9f50fad6 | 2145 | mutex_lock(&percpu_charge_mutex); |
c0ff4b85 | 2146 | drain_all_stock(root_memcg, true); |
9f50fad6 | 2147 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2148 | } |
2149 | ||
711d3d2c KH |
2150 | /* |
2151 | * This function drains percpu counter value from DEAD cpu and | |
2152 | * move it to local cpu. Note that this function can be preempted. | |
2153 | */ | |
c0ff4b85 | 2154 | static void mem_cgroup_drain_pcp_counter(struct mem_cgroup *memcg, int cpu) |
711d3d2c KH |
2155 | { |
2156 | int i; | |
2157 | ||
c0ff4b85 | 2158 | spin_lock(&memcg->pcp_counter_lock); |
711d3d2c | 2159 | for (i = 0; i < MEM_CGROUP_STAT_DATA; i++) { |
c0ff4b85 | 2160 | long x = per_cpu(memcg->stat->count[i], cpu); |
711d3d2c | 2161 | |
c0ff4b85 R |
2162 | per_cpu(memcg->stat->count[i], cpu) = 0; |
2163 | memcg->nocpu_base.count[i] += x; | |
711d3d2c | 2164 | } |
e9f8974f | 2165 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) { |
c0ff4b85 | 2166 | unsigned long x = per_cpu(memcg->stat->events[i], cpu); |
e9f8974f | 2167 | |
c0ff4b85 R |
2168 | per_cpu(memcg->stat->events[i], cpu) = 0; |
2169 | memcg->nocpu_base.events[i] += x; | |
e9f8974f | 2170 | } |
1489ebad | 2171 | /* need to clear ON_MOVE value, works as a kind of lock. */ |
c0ff4b85 R |
2172 | per_cpu(memcg->stat->count[MEM_CGROUP_ON_MOVE], cpu) = 0; |
2173 | spin_unlock(&memcg->pcp_counter_lock); | |
1489ebad KH |
2174 | } |
2175 | ||
c0ff4b85 | 2176 | static void synchronize_mem_cgroup_on_move(struct mem_cgroup *memcg, int cpu) |
1489ebad KH |
2177 | { |
2178 | int idx = MEM_CGROUP_ON_MOVE; | |
2179 | ||
c0ff4b85 R |
2180 | spin_lock(&memcg->pcp_counter_lock); |
2181 | per_cpu(memcg->stat->count[idx], cpu) = memcg->nocpu_base.count[idx]; | |
2182 | spin_unlock(&memcg->pcp_counter_lock); | |
711d3d2c KH |
2183 | } |
2184 | ||
2185 | static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, | |
cdec2e42 KH |
2186 | unsigned long action, |
2187 | void *hcpu) | |
2188 | { | |
2189 | int cpu = (unsigned long)hcpu; | |
2190 | struct memcg_stock_pcp *stock; | |
711d3d2c | 2191 | struct mem_cgroup *iter; |
cdec2e42 | 2192 | |
1489ebad | 2193 | if ((action == CPU_ONLINE)) { |
9f3a0d09 | 2194 | for_each_mem_cgroup(iter) |
1489ebad KH |
2195 | synchronize_mem_cgroup_on_move(iter, cpu); |
2196 | return NOTIFY_OK; | |
2197 | } | |
2198 | ||
711d3d2c | 2199 | if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN) |
cdec2e42 | 2200 | return NOTIFY_OK; |
711d3d2c | 2201 | |
9f3a0d09 | 2202 | for_each_mem_cgroup(iter) |
711d3d2c KH |
2203 | mem_cgroup_drain_pcp_counter(iter, cpu); |
2204 | ||
cdec2e42 KH |
2205 | stock = &per_cpu(memcg_stock, cpu); |
2206 | drain_stock(stock); | |
2207 | return NOTIFY_OK; | |
2208 | } | |
2209 | ||
4b534334 KH |
2210 | |
2211 | /* See __mem_cgroup_try_charge() for details */ | |
2212 | enum { | |
2213 | CHARGE_OK, /* success */ | |
2214 | CHARGE_RETRY, /* need to retry but retry is not bad */ | |
2215 | CHARGE_NOMEM, /* we can't do more. return -ENOMEM */ | |
2216 | CHARGE_WOULDBLOCK, /* GFP_WAIT wasn't set and no enough res. */ | |
2217 | CHARGE_OOM_DIE, /* the current is killed because of OOM */ | |
2218 | }; | |
2219 | ||
c0ff4b85 | 2220 | static int mem_cgroup_do_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, |
7ec99d62 | 2221 | unsigned int nr_pages, bool oom_check) |
4b534334 | 2222 | { |
7ec99d62 | 2223 | unsigned long csize = nr_pages * PAGE_SIZE; |
4b534334 KH |
2224 | struct mem_cgroup *mem_over_limit; |
2225 | struct res_counter *fail_res; | |
2226 | unsigned long flags = 0; | |
2227 | int ret; | |
2228 | ||
c0ff4b85 | 2229 | ret = res_counter_charge(&memcg->res, csize, &fail_res); |
4b534334 KH |
2230 | |
2231 | if (likely(!ret)) { | |
2232 | if (!do_swap_account) | |
2233 | return CHARGE_OK; | |
c0ff4b85 | 2234 | ret = res_counter_charge(&memcg->memsw, csize, &fail_res); |
4b534334 KH |
2235 | if (likely(!ret)) |
2236 | return CHARGE_OK; | |
2237 | ||
c0ff4b85 | 2238 | res_counter_uncharge(&memcg->res, csize); |
4b534334 KH |
2239 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw); |
2240 | flags |= MEM_CGROUP_RECLAIM_NOSWAP; | |
2241 | } else | |
2242 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, res); | |
9221edb7 | 2243 | /* |
7ec99d62 JW |
2244 | * nr_pages can be either a huge page (HPAGE_PMD_NR), a batch |
2245 | * of regular pages (CHARGE_BATCH), or a single regular page (1). | |
9221edb7 JW |
2246 | * |
2247 | * Never reclaim on behalf of optional batching, retry with a | |
2248 | * single page instead. | |
2249 | */ | |
7ec99d62 | 2250 | if (nr_pages == CHARGE_BATCH) |
4b534334 KH |
2251 | return CHARGE_RETRY; |
2252 | ||
2253 | if (!(gfp_mask & __GFP_WAIT)) | |
2254 | return CHARGE_WOULDBLOCK; | |
2255 | ||
5660048c | 2256 | ret = mem_cgroup_reclaim(mem_over_limit, gfp_mask, flags); |
7ec99d62 | 2257 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
19942822 | 2258 | return CHARGE_RETRY; |
4b534334 | 2259 | /* |
19942822 JW |
2260 | * Even though the limit is exceeded at this point, reclaim |
2261 | * may have been able to free some pages. Retry the charge | |
2262 | * before killing the task. | |
2263 | * | |
2264 | * Only for regular pages, though: huge pages are rather | |
2265 | * unlikely to succeed so close to the limit, and we fall back | |
2266 | * to regular pages anyway in case of failure. | |
4b534334 | 2267 | */ |
7ec99d62 | 2268 | if (nr_pages == 1 && ret) |
4b534334 KH |
2269 | return CHARGE_RETRY; |
2270 | ||
2271 | /* | |
2272 | * At task move, charge accounts can be doubly counted. So, it's | |
2273 | * better to wait until the end of task_move if something is going on. | |
2274 | */ | |
2275 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2276 | return CHARGE_RETRY; | |
2277 | ||
2278 | /* If we don't need to call oom-killer at el, return immediately */ | |
2279 | if (!oom_check) | |
2280 | return CHARGE_NOMEM; | |
2281 | /* check OOM */ | |
2282 | if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask)) | |
2283 | return CHARGE_OOM_DIE; | |
2284 | ||
2285 | return CHARGE_RETRY; | |
2286 | } | |
2287 | ||
f817ed48 KH |
2288 | /* |
2289 | * Unlike exported interface, "oom" parameter is added. if oom==true, | |
2290 | * oom-killer can be invoked. | |
8a9f3ccd | 2291 | */ |
f817ed48 | 2292 | static int __mem_cgroup_try_charge(struct mm_struct *mm, |
ec168510 | 2293 | gfp_t gfp_mask, |
7ec99d62 | 2294 | unsigned int nr_pages, |
c0ff4b85 | 2295 | struct mem_cgroup **ptr, |
7ec99d62 | 2296 | bool oom) |
8a9f3ccd | 2297 | { |
7ec99d62 | 2298 | unsigned int batch = max(CHARGE_BATCH, nr_pages); |
4b534334 | 2299 | int nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; |
c0ff4b85 | 2300 | struct mem_cgroup *memcg = NULL; |
4b534334 | 2301 | int ret; |
a636b327 | 2302 | |
867578cb KH |
2303 | /* |
2304 | * Unlike gloval-vm's OOM-kill, we're not in memory shortage | |
2305 | * in system level. So, allow to go ahead dying process in addition to | |
2306 | * MEMDIE process. | |
2307 | */ | |
2308 | if (unlikely(test_thread_flag(TIF_MEMDIE) | |
2309 | || fatal_signal_pending(current))) | |
2310 | goto bypass; | |
a636b327 | 2311 | |
8a9f3ccd | 2312 | /* |
3be91277 HD |
2313 | * We always charge the cgroup the mm_struct belongs to. |
2314 | * The mm_struct's mem_cgroup changes on task migration if the | |
8a9f3ccd BS |
2315 | * thread group leader migrates. It's possible that mm is not |
2316 | * set, if so charge the init_mm (happens for pagecache usage). | |
2317 | */ | |
c0ff4b85 | 2318 | if (!*ptr && !mm) |
f75ca962 KH |
2319 | goto bypass; |
2320 | again: | |
c0ff4b85 R |
2321 | if (*ptr) { /* css should be a valid one */ |
2322 | memcg = *ptr; | |
2323 | VM_BUG_ON(css_is_removed(&memcg->css)); | |
2324 | if (mem_cgroup_is_root(memcg)) | |
f75ca962 | 2325 | goto done; |
c0ff4b85 | 2326 | if (nr_pages == 1 && consume_stock(memcg)) |
f75ca962 | 2327 | goto done; |
c0ff4b85 | 2328 | css_get(&memcg->css); |
4b534334 | 2329 | } else { |
f75ca962 | 2330 | struct task_struct *p; |
54595fe2 | 2331 | |
f75ca962 KH |
2332 | rcu_read_lock(); |
2333 | p = rcu_dereference(mm->owner); | |
f75ca962 | 2334 | /* |
ebb76ce1 | 2335 | * Because we don't have task_lock(), "p" can exit. |
c0ff4b85 | 2336 | * In that case, "memcg" can point to root or p can be NULL with |
ebb76ce1 KH |
2337 | * race with swapoff. Then, we have small risk of mis-accouning. |
2338 | * But such kind of mis-account by race always happens because | |
2339 | * we don't have cgroup_mutex(). It's overkill and we allo that | |
2340 | * small race, here. | |
2341 | * (*) swapoff at el will charge against mm-struct not against | |
2342 | * task-struct. So, mm->owner can be NULL. | |
f75ca962 | 2343 | */ |
c0ff4b85 R |
2344 | memcg = mem_cgroup_from_task(p); |
2345 | if (!memcg || mem_cgroup_is_root(memcg)) { | |
f75ca962 KH |
2346 | rcu_read_unlock(); |
2347 | goto done; | |
2348 | } | |
c0ff4b85 | 2349 | if (nr_pages == 1 && consume_stock(memcg)) { |
f75ca962 KH |
2350 | /* |
2351 | * It seems dagerous to access memcg without css_get(). | |
2352 | * But considering how consume_stok works, it's not | |
2353 | * necessary. If consume_stock success, some charges | |
2354 | * from this memcg are cached on this cpu. So, we | |
2355 | * don't need to call css_get()/css_tryget() before | |
2356 | * calling consume_stock(). | |
2357 | */ | |
2358 | rcu_read_unlock(); | |
2359 | goto done; | |
2360 | } | |
2361 | /* after here, we may be blocked. we need to get refcnt */ | |
c0ff4b85 | 2362 | if (!css_tryget(&memcg->css)) { |
f75ca962 KH |
2363 | rcu_read_unlock(); |
2364 | goto again; | |
2365 | } | |
2366 | rcu_read_unlock(); | |
2367 | } | |
8a9f3ccd | 2368 | |
4b534334 KH |
2369 | do { |
2370 | bool oom_check; | |
7a81b88c | 2371 | |
4b534334 | 2372 | /* If killed, bypass charge */ |
f75ca962 | 2373 | if (fatal_signal_pending(current)) { |
c0ff4b85 | 2374 | css_put(&memcg->css); |
4b534334 | 2375 | goto bypass; |
f75ca962 | 2376 | } |
6d61ef40 | 2377 | |
4b534334 KH |
2378 | oom_check = false; |
2379 | if (oom && !nr_oom_retries) { | |
2380 | oom_check = true; | |
2381 | nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
cdec2e42 | 2382 | } |
66e1707b | 2383 | |
c0ff4b85 | 2384 | ret = mem_cgroup_do_charge(memcg, gfp_mask, batch, oom_check); |
4b534334 KH |
2385 | switch (ret) { |
2386 | case CHARGE_OK: | |
2387 | break; | |
2388 | case CHARGE_RETRY: /* not in OOM situation but retry */ | |
7ec99d62 | 2389 | batch = nr_pages; |
c0ff4b85 R |
2390 | css_put(&memcg->css); |
2391 | memcg = NULL; | |
f75ca962 | 2392 | goto again; |
4b534334 | 2393 | case CHARGE_WOULDBLOCK: /* !__GFP_WAIT */ |
c0ff4b85 | 2394 | css_put(&memcg->css); |
4b534334 KH |
2395 | goto nomem; |
2396 | case CHARGE_NOMEM: /* OOM routine works */ | |
f75ca962 | 2397 | if (!oom) { |
c0ff4b85 | 2398 | css_put(&memcg->css); |
867578cb | 2399 | goto nomem; |
f75ca962 | 2400 | } |
4b534334 KH |
2401 | /* If oom, we never return -ENOMEM */ |
2402 | nr_oom_retries--; | |
2403 | break; | |
2404 | case CHARGE_OOM_DIE: /* Killed by OOM Killer */ | |
c0ff4b85 | 2405 | css_put(&memcg->css); |
867578cb | 2406 | goto bypass; |
66e1707b | 2407 | } |
4b534334 KH |
2408 | } while (ret != CHARGE_OK); |
2409 | ||
7ec99d62 | 2410 | if (batch > nr_pages) |
c0ff4b85 R |
2411 | refill_stock(memcg, batch - nr_pages); |
2412 | css_put(&memcg->css); | |
0c3e73e8 | 2413 | done: |
c0ff4b85 | 2414 | *ptr = memcg; |
7a81b88c KH |
2415 | return 0; |
2416 | nomem: | |
c0ff4b85 | 2417 | *ptr = NULL; |
7a81b88c | 2418 | return -ENOMEM; |
867578cb | 2419 | bypass: |
c0ff4b85 | 2420 | *ptr = NULL; |
867578cb | 2421 | return 0; |
7a81b88c | 2422 | } |
8a9f3ccd | 2423 | |
a3032a2c DN |
2424 | /* |
2425 | * Somemtimes we have to undo a charge we got by try_charge(). | |
2426 | * This function is for that and do uncharge, put css's refcnt. | |
2427 | * gotten by try_charge(). | |
2428 | */ | |
c0ff4b85 | 2429 | static void __mem_cgroup_cancel_charge(struct mem_cgroup *memcg, |
e7018b8d | 2430 | unsigned int nr_pages) |
a3032a2c | 2431 | { |
c0ff4b85 | 2432 | if (!mem_cgroup_is_root(memcg)) { |
e7018b8d JW |
2433 | unsigned long bytes = nr_pages * PAGE_SIZE; |
2434 | ||
c0ff4b85 | 2435 | res_counter_uncharge(&memcg->res, bytes); |
a3032a2c | 2436 | if (do_swap_account) |
c0ff4b85 | 2437 | res_counter_uncharge(&memcg->memsw, bytes); |
a3032a2c | 2438 | } |
854ffa8d DN |
2439 | } |
2440 | ||
a3b2d692 KH |
2441 | /* |
2442 | * A helper function to get mem_cgroup from ID. must be called under | |
2443 | * rcu_read_lock(). The caller must check css_is_removed() or some if | |
2444 | * it's concern. (dropping refcnt from swap can be called against removed | |
2445 | * memcg.) | |
2446 | */ | |
2447 | static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) | |
2448 | { | |
2449 | struct cgroup_subsys_state *css; | |
2450 | ||
2451 | /* ID 0 is unused ID */ | |
2452 | if (!id) | |
2453 | return NULL; | |
2454 | css = css_lookup(&mem_cgroup_subsys, id); | |
2455 | if (!css) | |
2456 | return NULL; | |
2457 | return container_of(css, struct mem_cgroup, css); | |
2458 | } | |
2459 | ||
e42d9d5d | 2460 | struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) |
b5a84319 | 2461 | { |
c0ff4b85 | 2462 | struct mem_cgroup *memcg = NULL; |
3c776e64 | 2463 | struct page_cgroup *pc; |
a3b2d692 | 2464 | unsigned short id; |
b5a84319 KH |
2465 | swp_entry_t ent; |
2466 | ||
3c776e64 DN |
2467 | VM_BUG_ON(!PageLocked(page)); |
2468 | ||
3c776e64 | 2469 | pc = lookup_page_cgroup(page); |
c0bd3f63 | 2470 | lock_page_cgroup(pc); |
a3b2d692 | 2471 | if (PageCgroupUsed(pc)) { |
c0ff4b85 R |
2472 | memcg = pc->mem_cgroup; |
2473 | if (memcg && !css_tryget(&memcg->css)) | |
2474 | memcg = NULL; | |
e42d9d5d | 2475 | } else if (PageSwapCache(page)) { |
3c776e64 | 2476 | ent.val = page_private(page); |
a3b2d692 KH |
2477 | id = lookup_swap_cgroup(ent); |
2478 | rcu_read_lock(); | |
c0ff4b85 R |
2479 | memcg = mem_cgroup_lookup(id); |
2480 | if (memcg && !css_tryget(&memcg->css)) | |
2481 | memcg = NULL; | |
a3b2d692 | 2482 | rcu_read_unlock(); |
3c776e64 | 2483 | } |
c0bd3f63 | 2484 | unlock_page_cgroup(pc); |
c0ff4b85 | 2485 | return memcg; |
b5a84319 KH |
2486 | } |
2487 | ||
c0ff4b85 | 2488 | static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, |
5564e88b | 2489 | struct page *page, |
7ec99d62 | 2490 | unsigned int nr_pages, |
ca3e0214 | 2491 | struct page_cgroup *pc, |
7ec99d62 | 2492 | enum charge_type ctype) |
7a81b88c | 2493 | { |
ca3e0214 KH |
2494 | lock_page_cgroup(pc); |
2495 | if (unlikely(PageCgroupUsed(pc))) { | |
2496 | unlock_page_cgroup(pc); | |
c0ff4b85 | 2497 | __mem_cgroup_cancel_charge(memcg, nr_pages); |
ca3e0214 KH |
2498 | return; |
2499 | } | |
2500 | /* | |
2501 | * we don't need page_cgroup_lock about tail pages, becase they are not | |
2502 | * accessed by any other context at this point. | |
2503 | */ | |
c0ff4b85 | 2504 | pc->mem_cgroup = memcg; |
261fb61a KH |
2505 | /* |
2506 | * We access a page_cgroup asynchronously without lock_page_cgroup(). | |
2507 | * Especially when a page_cgroup is taken from a page, pc->mem_cgroup | |
2508 | * is accessed after testing USED bit. To make pc->mem_cgroup visible | |
2509 | * before USED bit, we need memory barrier here. | |
2510 | * See mem_cgroup_add_lru_list(), etc. | |
2511 | */ | |
08e552c6 | 2512 | smp_wmb(); |
4b3bde4c BS |
2513 | switch (ctype) { |
2514 | case MEM_CGROUP_CHARGE_TYPE_CACHE: | |
2515 | case MEM_CGROUP_CHARGE_TYPE_SHMEM: | |
2516 | SetPageCgroupCache(pc); | |
2517 | SetPageCgroupUsed(pc); | |
2518 | break; | |
2519 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
2520 | ClearPageCgroupCache(pc); | |
2521 | SetPageCgroupUsed(pc); | |
2522 | break; | |
2523 | default: | |
2524 | break; | |
2525 | } | |
3be91277 | 2526 | |
c0ff4b85 | 2527 | mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), nr_pages); |
52d4b9ac | 2528 | unlock_page_cgroup(pc); |
430e4863 KH |
2529 | /* |
2530 | * "charge_statistics" updated event counter. Then, check it. | |
2531 | * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree. | |
2532 | * if they exceeds softlimit. | |
2533 | */ | |
c0ff4b85 | 2534 | memcg_check_events(memcg, page); |
7a81b88c | 2535 | } |
66e1707b | 2536 | |
ca3e0214 KH |
2537 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
2538 | ||
2539 | #define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) | (1 << PCG_MOVE_LOCK) |\ | |
2540 | (1 << PCG_ACCT_LRU) | (1 << PCG_MIGRATION)) | |
2541 | /* | |
2542 | * Because tail pages are not marked as "used", set it. We're under | |
e94c8a9c KH |
2543 | * zone->lru_lock, 'splitting on pmd' and compound_lock. |
2544 | * charge/uncharge will be never happen and move_account() is done under | |
2545 | * compound_lock(), so we don't have to take care of races. | |
ca3e0214 | 2546 | */ |
e94c8a9c | 2547 | void mem_cgroup_split_huge_fixup(struct page *head) |
ca3e0214 KH |
2548 | { |
2549 | struct page_cgroup *head_pc = lookup_page_cgroup(head); | |
e94c8a9c KH |
2550 | struct page_cgroup *pc; |
2551 | int i; | |
ca3e0214 | 2552 | |
3d37c4a9 KH |
2553 | if (mem_cgroup_disabled()) |
2554 | return; | |
e94c8a9c KH |
2555 | for (i = 1; i < HPAGE_PMD_NR; i++) { |
2556 | pc = head_pc + i; | |
2557 | pc->mem_cgroup = head_pc->mem_cgroup; | |
2558 | smp_wmb();/* see __commit_charge() */ | |
2559 | /* | |
2560 | * LRU flags cannot be copied because we need to add tail | |
2561 | * page to LRU by generic call and our hooks will be called. | |
2562 | */ | |
2563 | pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT; | |
2564 | } | |
ca3e0214 | 2565 | |
ece35ca8 KH |
2566 | if (PageCgroupAcctLRU(head_pc)) { |
2567 | enum lru_list lru; | |
2568 | struct mem_cgroup_per_zone *mz; | |
ece35ca8 | 2569 | /* |
ece35ca8 KH |
2570 | * We hold lru_lock, then, reduce counter directly. |
2571 | */ | |
2572 | lru = page_lru(head); | |
97a6c37b | 2573 | mz = page_cgroup_zoneinfo(head_pc->mem_cgroup, head); |
e94c8a9c | 2574 | MEM_CGROUP_ZSTAT(mz, lru) -= HPAGE_PMD_NR - 1; |
ece35ca8 | 2575 | } |
ca3e0214 KH |
2576 | } |
2577 | #endif | |
2578 | ||
f817ed48 | 2579 | /** |
de3638d9 | 2580 | * mem_cgroup_move_account - move account of the page |
5564e88b | 2581 | * @page: the page |
7ec99d62 | 2582 | * @nr_pages: number of regular pages (>1 for huge pages) |
f817ed48 KH |
2583 | * @pc: page_cgroup of the page. |
2584 | * @from: mem_cgroup which the page is moved from. | |
2585 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
854ffa8d | 2586 | * @uncharge: whether we should call uncharge and css_put against @from. |
f817ed48 KH |
2587 | * |
2588 | * The caller must confirm following. | |
08e552c6 | 2589 | * - page is not on LRU (isolate_page() is useful.) |
7ec99d62 | 2590 | * - compound_lock is held when nr_pages > 1 |
f817ed48 | 2591 | * |
854ffa8d | 2592 | * This function doesn't do "charge" nor css_get to new cgroup. It should be |
25985edc | 2593 | * done by a caller(__mem_cgroup_try_charge would be useful). If @uncharge is |
854ffa8d DN |
2594 | * true, this function does "uncharge" from old cgroup, but it doesn't if |
2595 | * @uncharge is false, so a caller should do "uncharge". | |
f817ed48 | 2596 | */ |
7ec99d62 JW |
2597 | static int mem_cgroup_move_account(struct page *page, |
2598 | unsigned int nr_pages, | |
2599 | struct page_cgroup *pc, | |
2600 | struct mem_cgroup *from, | |
2601 | struct mem_cgroup *to, | |
2602 | bool uncharge) | |
f817ed48 | 2603 | { |
de3638d9 JW |
2604 | unsigned long flags; |
2605 | int ret; | |
987eba66 | 2606 | |
f817ed48 | 2607 | VM_BUG_ON(from == to); |
5564e88b | 2608 | VM_BUG_ON(PageLRU(page)); |
de3638d9 JW |
2609 | /* |
2610 | * The page is isolated from LRU. So, collapse function | |
2611 | * will not handle this page. But page splitting can happen. | |
2612 | * Do this check under compound_page_lock(). The caller should | |
2613 | * hold it. | |
2614 | */ | |
2615 | ret = -EBUSY; | |
7ec99d62 | 2616 | if (nr_pages > 1 && !PageTransHuge(page)) |
de3638d9 JW |
2617 | goto out; |
2618 | ||
2619 | lock_page_cgroup(pc); | |
2620 | ||
2621 | ret = -EINVAL; | |
2622 | if (!PageCgroupUsed(pc) || pc->mem_cgroup != from) | |
2623 | goto unlock; | |
2624 | ||
2625 | move_lock_page_cgroup(pc, &flags); | |
f817ed48 | 2626 | |
8725d541 | 2627 | if (PageCgroupFileMapped(pc)) { |
c62b1a3b KH |
2628 | /* Update mapped_file data for mem_cgroup */ |
2629 | preempt_disable(); | |
2630 | __this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2631 | __this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2632 | preempt_enable(); | |
d69b042f | 2633 | } |
987eba66 | 2634 | mem_cgroup_charge_statistics(from, PageCgroupCache(pc), -nr_pages); |
854ffa8d DN |
2635 | if (uncharge) |
2636 | /* This is not "cancel", but cancel_charge does all we need. */ | |
e7018b8d | 2637 | __mem_cgroup_cancel_charge(from, nr_pages); |
d69b042f | 2638 | |
854ffa8d | 2639 | /* caller should have done css_get */ |
08e552c6 | 2640 | pc->mem_cgroup = to; |
987eba66 | 2641 | mem_cgroup_charge_statistics(to, PageCgroupCache(pc), nr_pages); |
88703267 KH |
2642 | /* |
2643 | * We charges against "to" which may not have any tasks. Then, "to" | |
2644 | * can be under rmdir(). But in current implementation, caller of | |
4ffef5fe | 2645 | * this function is just force_empty() and move charge, so it's |
25985edc | 2646 | * guaranteed that "to" is never removed. So, we don't check rmdir |
4ffef5fe | 2647 | * status here. |
88703267 | 2648 | */ |
de3638d9 JW |
2649 | move_unlock_page_cgroup(pc, &flags); |
2650 | ret = 0; | |
2651 | unlock: | |
57f9fd7d | 2652 | unlock_page_cgroup(pc); |
d2265e6f KH |
2653 | /* |
2654 | * check events | |
2655 | */ | |
5564e88b JW |
2656 | memcg_check_events(to, page); |
2657 | memcg_check_events(from, page); | |
de3638d9 | 2658 | out: |
f817ed48 KH |
2659 | return ret; |
2660 | } | |
2661 | ||
2662 | /* | |
2663 | * move charges to its parent. | |
2664 | */ | |
2665 | ||
5564e88b JW |
2666 | static int mem_cgroup_move_parent(struct page *page, |
2667 | struct page_cgroup *pc, | |
f817ed48 KH |
2668 | struct mem_cgroup *child, |
2669 | gfp_t gfp_mask) | |
2670 | { | |
2671 | struct cgroup *cg = child->css.cgroup; | |
2672 | struct cgroup *pcg = cg->parent; | |
2673 | struct mem_cgroup *parent; | |
7ec99d62 | 2674 | unsigned int nr_pages; |
4be4489f | 2675 | unsigned long uninitialized_var(flags); |
f817ed48 KH |
2676 | int ret; |
2677 | ||
2678 | /* Is ROOT ? */ | |
2679 | if (!pcg) | |
2680 | return -EINVAL; | |
2681 | ||
57f9fd7d DN |
2682 | ret = -EBUSY; |
2683 | if (!get_page_unless_zero(page)) | |
2684 | goto out; | |
2685 | if (isolate_lru_page(page)) | |
2686 | goto put; | |
52dbb905 | 2687 | |
7ec99d62 | 2688 | nr_pages = hpage_nr_pages(page); |
08e552c6 | 2689 | |
f817ed48 | 2690 | parent = mem_cgroup_from_cont(pcg); |
7ec99d62 | 2691 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, nr_pages, &parent, false); |
a636b327 | 2692 | if (ret || !parent) |
57f9fd7d | 2693 | goto put_back; |
f817ed48 | 2694 | |
7ec99d62 | 2695 | if (nr_pages > 1) |
987eba66 KH |
2696 | flags = compound_lock_irqsave(page); |
2697 | ||
7ec99d62 | 2698 | ret = mem_cgroup_move_account(page, nr_pages, pc, child, parent, true); |
854ffa8d | 2699 | if (ret) |
7ec99d62 | 2700 | __mem_cgroup_cancel_charge(parent, nr_pages); |
8dba474f | 2701 | |
7ec99d62 | 2702 | if (nr_pages > 1) |
987eba66 | 2703 | compound_unlock_irqrestore(page, flags); |
8dba474f | 2704 | put_back: |
08e552c6 | 2705 | putback_lru_page(page); |
57f9fd7d | 2706 | put: |
40d58138 | 2707 | put_page(page); |
57f9fd7d | 2708 | out: |
f817ed48 KH |
2709 | return ret; |
2710 | } | |
2711 | ||
7a81b88c KH |
2712 | /* |
2713 | * Charge the memory controller for page usage. | |
2714 | * Return | |
2715 | * 0 if the charge was successful | |
2716 | * < 0 if the cgroup is over its limit | |
2717 | */ | |
2718 | static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, | |
73045c47 | 2719 | gfp_t gfp_mask, enum charge_type ctype) |
7a81b88c | 2720 | { |
c0ff4b85 | 2721 | struct mem_cgroup *memcg = NULL; |
7ec99d62 | 2722 | unsigned int nr_pages = 1; |
7a81b88c | 2723 | struct page_cgroup *pc; |
8493ae43 | 2724 | bool oom = true; |
7a81b88c | 2725 | int ret; |
ec168510 | 2726 | |
37c2ac78 | 2727 | if (PageTransHuge(page)) { |
7ec99d62 | 2728 | nr_pages <<= compound_order(page); |
37c2ac78 | 2729 | VM_BUG_ON(!PageTransHuge(page)); |
8493ae43 JW |
2730 | /* |
2731 | * Never OOM-kill a process for a huge page. The | |
2732 | * fault handler will fall back to regular pages. | |
2733 | */ | |
2734 | oom = false; | |
37c2ac78 | 2735 | } |
7a81b88c KH |
2736 | |
2737 | pc = lookup_page_cgroup(page); | |
af4a6621 | 2738 | BUG_ON(!pc); /* XXX: remove this and move pc lookup into commit */ |
7a81b88c | 2739 | |
c0ff4b85 R |
2740 | ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &memcg, oom); |
2741 | if (ret || !memcg) | |
7a81b88c KH |
2742 | return ret; |
2743 | ||
c0ff4b85 | 2744 | __mem_cgroup_commit_charge(memcg, page, nr_pages, pc, ctype); |
8a9f3ccd | 2745 | return 0; |
8a9f3ccd BS |
2746 | } |
2747 | ||
7a81b88c KH |
2748 | int mem_cgroup_newpage_charge(struct page *page, |
2749 | struct mm_struct *mm, gfp_t gfp_mask) | |
217bc319 | 2750 | { |
f8d66542 | 2751 | if (mem_cgroup_disabled()) |
cede86ac | 2752 | return 0; |
69029cd5 KH |
2753 | /* |
2754 | * If already mapped, we don't have to account. | |
2755 | * If page cache, page->mapping has address_space. | |
2756 | * But page->mapping may have out-of-use anon_vma pointer, | |
2757 | * detecit it by PageAnon() check. newly-mapped-anon's page->mapping | |
2758 | * is NULL. | |
2759 | */ | |
2760 | if (page_mapped(page) || (page->mapping && !PageAnon(page))) | |
2761 | return 0; | |
2762 | if (unlikely(!mm)) | |
2763 | mm = &init_mm; | |
217bc319 | 2764 | return mem_cgroup_charge_common(page, mm, gfp_mask, |
73045c47 | 2765 | MEM_CGROUP_CHARGE_TYPE_MAPPED); |
217bc319 KH |
2766 | } |
2767 | ||
83aae4c7 DN |
2768 | static void |
2769 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
2770 | enum charge_type ctype); | |
2771 | ||
5a6475a4 | 2772 | static void |
c0ff4b85 | 2773 | __mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *memcg, |
5a6475a4 KH |
2774 | enum charge_type ctype) |
2775 | { | |
2776 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
2777 | /* | |
2778 | * In some case, SwapCache, FUSE(splice_buf->radixtree), the page | |
2779 | * is already on LRU. It means the page may on some other page_cgroup's | |
2780 | * LRU. Take care of it. | |
2781 | */ | |
2782 | mem_cgroup_lru_del_before_commit(page); | |
c0ff4b85 | 2783 | __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype); |
5a6475a4 KH |
2784 | mem_cgroup_lru_add_after_commit(page); |
2785 | return; | |
2786 | } | |
2787 | ||
e1a1cd59 BS |
2788 | int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, |
2789 | gfp_t gfp_mask) | |
8697d331 | 2790 | { |
c0ff4b85 | 2791 | struct mem_cgroup *memcg = NULL; |
b5a84319 KH |
2792 | int ret; |
2793 | ||
f8d66542 | 2794 | if (mem_cgroup_disabled()) |
cede86ac | 2795 | return 0; |
52d4b9ac KH |
2796 | if (PageCompound(page)) |
2797 | return 0; | |
accf163e | 2798 | |
73045c47 | 2799 | if (unlikely(!mm)) |
8697d331 | 2800 | mm = &init_mm; |
accf163e | 2801 | |
5a6475a4 | 2802 | if (page_is_file_cache(page)) { |
c0ff4b85 R |
2803 | ret = __mem_cgroup_try_charge(mm, gfp_mask, 1, &memcg, true); |
2804 | if (ret || !memcg) | |
5a6475a4 | 2805 | return ret; |
b5a84319 | 2806 | |
5a6475a4 KH |
2807 | /* |
2808 | * FUSE reuses pages without going through the final | |
2809 | * put that would remove them from the LRU list, make | |
2810 | * sure that they get relinked properly. | |
2811 | */ | |
c0ff4b85 | 2812 | __mem_cgroup_commit_charge_lrucare(page, memcg, |
5a6475a4 KH |
2813 | MEM_CGROUP_CHARGE_TYPE_CACHE); |
2814 | return ret; | |
2815 | } | |
83aae4c7 DN |
2816 | /* shmem */ |
2817 | if (PageSwapCache(page)) { | |
c0ff4b85 | 2818 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &memcg); |
83aae4c7 | 2819 | if (!ret) |
c0ff4b85 | 2820 | __mem_cgroup_commit_charge_swapin(page, memcg, |
83aae4c7 DN |
2821 | MEM_CGROUP_CHARGE_TYPE_SHMEM); |
2822 | } else | |
2823 | ret = mem_cgroup_charge_common(page, mm, gfp_mask, | |
73045c47 | 2824 | MEM_CGROUP_CHARGE_TYPE_SHMEM); |
b5a84319 | 2825 | |
b5a84319 | 2826 | return ret; |
e8589cc1 KH |
2827 | } |
2828 | ||
54595fe2 KH |
2829 | /* |
2830 | * While swap-in, try_charge -> commit or cancel, the page is locked. | |
2831 | * And when try_charge() successfully returns, one refcnt to memcg without | |
21ae2956 | 2832 | * struct page_cgroup is acquired. This refcnt will be consumed by |
54595fe2 KH |
2833 | * "commit()" or removed by "cancel()" |
2834 | */ | |
8c7c6e34 KH |
2835 | int mem_cgroup_try_charge_swapin(struct mm_struct *mm, |
2836 | struct page *page, | |
72835c86 | 2837 | gfp_t mask, struct mem_cgroup **memcgp) |
8c7c6e34 | 2838 | { |
c0ff4b85 | 2839 | struct mem_cgroup *memcg; |
54595fe2 | 2840 | int ret; |
8c7c6e34 | 2841 | |
72835c86 | 2842 | *memcgp = NULL; |
56039efa | 2843 | |
f8d66542 | 2844 | if (mem_cgroup_disabled()) |
8c7c6e34 KH |
2845 | return 0; |
2846 | ||
2847 | if (!do_swap_account) | |
2848 | goto charge_cur_mm; | |
8c7c6e34 KH |
2849 | /* |
2850 | * A racing thread's fault, or swapoff, may have already updated | |
407f9c8b HD |
2851 | * the pte, and even removed page from swap cache: in those cases |
2852 | * do_swap_page()'s pte_same() test will fail; but there's also a | |
2853 | * KSM case which does need to charge the page. | |
8c7c6e34 KH |
2854 | */ |
2855 | if (!PageSwapCache(page)) | |
407f9c8b | 2856 | goto charge_cur_mm; |
c0ff4b85 R |
2857 | memcg = try_get_mem_cgroup_from_page(page); |
2858 | if (!memcg) | |
54595fe2 | 2859 | goto charge_cur_mm; |
72835c86 JW |
2860 | *memcgp = memcg; |
2861 | ret = __mem_cgroup_try_charge(NULL, mask, 1, memcgp, true); | |
c0ff4b85 | 2862 | css_put(&memcg->css); |
54595fe2 | 2863 | return ret; |
8c7c6e34 KH |
2864 | charge_cur_mm: |
2865 | if (unlikely(!mm)) | |
2866 | mm = &init_mm; | |
72835c86 | 2867 | return __mem_cgroup_try_charge(mm, mask, 1, memcgp, true); |
8c7c6e34 KH |
2868 | } |
2869 | ||
83aae4c7 | 2870 | static void |
72835c86 | 2871 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg, |
83aae4c7 | 2872 | enum charge_type ctype) |
7a81b88c | 2873 | { |
f8d66542 | 2874 | if (mem_cgroup_disabled()) |
7a81b88c | 2875 | return; |
72835c86 | 2876 | if (!memcg) |
7a81b88c | 2877 | return; |
72835c86 | 2878 | cgroup_exclude_rmdir(&memcg->css); |
5a6475a4 | 2879 | |
72835c86 | 2880 | __mem_cgroup_commit_charge_lrucare(page, memcg, ctype); |
8c7c6e34 KH |
2881 | /* |
2882 | * Now swap is on-memory. This means this page may be | |
2883 | * counted both as mem and swap....double count. | |
03f3c433 KH |
2884 | * Fix it by uncharging from memsw. Basically, this SwapCache is stable |
2885 | * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page() | |
2886 | * may call delete_from_swap_cache() before reach here. | |
8c7c6e34 | 2887 | */ |
03f3c433 | 2888 | if (do_swap_account && PageSwapCache(page)) { |
8c7c6e34 | 2889 | swp_entry_t ent = {.val = page_private(page)}; |
72835c86 | 2890 | struct mem_cgroup *swap_memcg; |
a3b2d692 | 2891 | unsigned short id; |
a3b2d692 KH |
2892 | |
2893 | id = swap_cgroup_record(ent, 0); | |
2894 | rcu_read_lock(); | |
72835c86 JW |
2895 | swap_memcg = mem_cgroup_lookup(id); |
2896 | if (swap_memcg) { | |
a3b2d692 KH |
2897 | /* |
2898 | * This recorded memcg can be obsolete one. So, avoid | |
2899 | * calling css_tryget | |
2900 | */ | |
72835c86 JW |
2901 | if (!mem_cgroup_is_root(swap_memcg)) |
2902 | res_counter_uncharge(&swap_memcg->memsw, | |
2903 | PAGE_SIZE); | |
2904 | mem_cgroup_swap_statistics(swap_memcg, false); | |
2905 | mem_cgroup_put(swap_memcg); | |
8c7c6e34 | 2906 | } |
a3b2d692 | 2907 | rcu_read_unlock(); |
8c7c6e34 | 2908 | } |
88703267 KH |
2909 | /* |
2910 | * At swapin, we may charge account against cgroup which has no tasks. | |
2911 | * So, rmdir()->pre_destroy() can be called while we do this charge. | |
2912 | * In that case, we need to call pre_destroy() again. check it here. | |
2913 | */ | |
72835c86 | 2914 | cgroup_release_and_wakeup_rmdir(&memcg->css); |
7a81b88c KH |
2915 | } |
2916 | ||
72835c86 JW |
2917 | void mem_cgroup_commit_charge_swapin(struct page *page, |
2918 | struct mem_cgroup *memcg) | |
83aae4c7 | 2919 | { |
72835c86 JW |
2920 | __mem_cgroup_commit_charge_swapin(page, memcg, |
2921 | MEM_CGROUP_CHARGE_TYPE_MAPPED); | |
83aae4c7 DN |
2922 | } |
2923 | ||
c0ff4b85 | 2924 | void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg) |
7a81b88c | 2925 | { |
f8d66542 | 2926 | if (mem_cgroup_disabled()) |
7a81b88c | 2927 | return; |
c0ff4b85 | 2928 | if (!memcg) |
7a81b88c | 2929 | return; |
c0ff4b85 | 2930 | __mem_cgroup_cancel_charge(memcg, 1); |
7a81b88c KH |
2931 | } |
2932 | ||
c0ff4b85 | 2933 | static void mem_cgroup_do_uncharge(struct mem_cgroup *memcg, |
7ec99d62 JW |
2934 | unsigned int nr_pages, |
2935 | const enum charge_type ctype) | |
569b846d KH |
2936 | { |
2937 | struct memcg_batch_info *batch = NULL; | |
2938 | bool uncharge_memsw = true; | |
7ec99d62 | 2939 | |
569b846d KH |
2940 | /* If swapout, usage of swap doesn't decrease */ |
2941 | if (!do_swap_account || ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) | |
2942 | uncharge_memsw = false; | |
569b846d KH |
2943 | |
2944 | batch = ¤t->memcg_batch; | |
2945 | /* | |
2946 | * In usual, we do css_get() when we remember memcg pointer. | |
2947 | * But in this case, we keep res->usage until end of a series of | |
2948 | * uncharges. Then, it's ok to ignore memcg's refcnt. | |
2949 | */ | |
2950 | if (!batch->memcg) | |
c0ff4b85 | 2951 | batch->memcg = memcg; |
3c11ecf4 KH |
2952 | /* |
2953 | * do_batch > 0 when unmapping pages or inode invalidate/truncate. | |
25985edc | 2954 | * In those cases, all pages freed continuously can be expected to be in |
3c11ecf4 KH |
2955 | * the same cgroup and we have chance to coalesce uncharges. |
2956 | * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE) | |
2957 | * because we want to do uncharge as soon as possible. | |
2958 | */ | |
2959 | ||
2960 | if (!batch->do_batch || test_thread_flag(TIF_MEMDIE)) | |
2961 | goto direct_uncharge; | |
2962 | ||
7ec99d62 | 2963 | if (nr_pages > 1) |
ec168510 AA |
2964 | goto direct_uncharge; |
2965 | ||
569b846d KH |
2966 | /* |
2967 | * In typical case, batch->memcg == mem. This means we can | |
2968 | * merge a series of uncharges to an uncharge of res_counter. | |
2969 | * If not, we uncharge res_counter ony by one. | |
2970 | */ | |
c0ff4b85 | 2971 | if (batch->memcg != memcg) |
569b846d KH |
2972 | goto direct_uncharge; |
2973 | /* remember freed charge and uncharge it later */ | |
7ffd4ca7 | 2974 | batch->nr_pages++; |
569b846d | 2975 | if (uncharge_memsw) |
7ffd4ca7 | 2976 | batch->memsw_nr_pages++; |
569b846d KH |
2977 | return; |
2978 | direct_uncharge: | |
c0ff4b85 | 2979 | res_counter_uncharge(&memcg->res, nr_pages * PAGE_SIZE); |
569b846d | 2980 | if (uncharge_memsw) |
c0ff4b85 R |
2981 | res_counter_uncharge(&memcg->memsw, nr_pages * PAGE_SIZE); |
2982 | if (unlikely(batch->memcg != memcg)) | |
2983 | memcg_oom_recover(memcg); | |
569b846d KH |
2984 | return; |
2985 | } | |
7a81b88c | 2986 | |
8a9f3ccd | 2987 | /* |
69029cd5 | 2988 | * uncharge if !page_mapped(page) |
8a9f3ccd | 2989 | */ |
8c7c6e34 | 2990 | static struct mem_cgroup * |
69029cd5 | 2991 | __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) |
8a9f3ccd | 2992 | { |
c0ff4b85 | 2993 | struct mem_cgroup *memcg = NULL; |
7ec99d62 JW |
2994 | unsigned int nr_pages = 1; |
2995 | struct page_cgroup *pc; | |
8a9f3ccd | 2996 | |
f8d66542 | 2997 | if (mem_cgroup_disabled()) |
8c7c6e34 | 2998 | return NULL; |
4077960e | 2999 | |
d13d1443 | 3000 | if (PageSwapCache(page)) |
8c7c6e34 | 3001 | return NULL; |
d13d1443 | 3002 | |
37c2ac78 | 3003 | if (PageTransHuge(page)) { |
7ec99d62 | 3004 | nr_pages <<= compound_order(page); |
37c2ac78 AA |
3005 | VM_BUG_ON(!PageTransHuge(page)); |
3006 | } | |
8697d331 | 3007 | /* |
3c541e14 | 3008 | * Check if our page_cgroup is valid |
8697d331 | 3009 | */ |
52d4b9ac KH |
3010 | pc = lookup_page_cgroup(page); |
3011 | if (unlikely(!pc || !PageCgroupUsed(pc))) | |
8c7c6e34 | 3012 | return NULL; |
b9c565d5 | 3013 | |
52d4b9ac | 3014 | lock_page_cgroup(pc); |
d13d1443 | 3015 | |
c0ff4b85 | 3016 | memcg = pc->mem_cgroup; |
8c7c6e34 | 3017 | |
d13d1443 KH |
3018 | if (!PageCgroupUsed(pc)) |
3019 | goto unlock_out; | |
3020 | ||
3021 | switch (ctype) { | |
3022 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
8a9478ca | 3023 | case MEM_CGROUP_CHARGE_TYPE_DROP: |
ac39cf8c AM |
3024 | /* See mem_cgroup_prepare_migration() */ |
3025 | if (page_mapped(page) || PageCgroupMigration(pc)) | |
d13d1443 KH |
3026 | goto unlock_out; |
3027 | break; | |
3028 | case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: | |
3029 | if (!PageAnon(page)) { /* Shared memory */ | |
3030 | if (page->mapping && !page_is_file_cache(page)) | |
3031 | goto unlock_out; | |
3032 | } else if (page_mapped(page)) /* Anon */ | |
3033 | goto unlock_out; | |
3034 | break; | |
3035 | default: | |
3036 | break; | |
52d4b9ac | 3037 | } |
d13d1443 | 3038 | |
c0ff4b85 | 3039 | mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), -nr_pages); |
04046e1a | 3040 | |
52d4b9ac | 3041 | ClearPageCgroupUsed(pc); |
544122e5 KH |
3042 | /* |
3043 | * pc->mem_cgroup is not cleared here. It will be accessed when it's | |
3044 | * freed from LRU. This is safe because uncharged page is expected not | |
3045 | * to be reused (freed soon). Exception is SwapCache, it's handled by | |
3046 | * special functions. | |
3047 | */ | |
b9c565d5 | 3048 | |
52d4b9ac | 3049 | unlock_page_cgroup(pc); |
f75ca962 | 3050 | /* |
c0ff4b85 | 3051 | * even after unlock, we have memcg->res.usage here and this memcg |
f75ca962 KH |
3052 | * will never be freed. |
3053 | */ | |
c0ff4b85 | 3054 | memcg_check_events(memcg, page); |
f75ca962 | 3055 | if (do_swap_account && ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) { |
c0ff4b85 R |
3056 | mem_cgroup_swap_statistics(memcg, true); |
3057 | mem_cgroup_get(memcg); | |
f75ca962 | 3058 | } |
c0ff4b85 R |
3059 | if (!mem_cgroup_is_root(memcg)) |
3060 | mem_cgroup_do_uncharge(memcg, nr_pages, ctype); | |
6d12e2d8 | 3061 | |
c0ff4b85 | 3062 | return memcg; |
d13d1443 KH |
3063 | |
3064 | unlock_out: | |
3065 | unlock_page_cgroup(pc); | |
8c7c6e34 | 3066 | return NULL; |
3c541e14 BS |
3067 | } |
3068 | ||
69029cd5 KH |
3069 | void mem_cgroup_uncharge_page(struct page *page) |
3070 | { | |
52d4b9ac KH |
3071 | /* early check. */ |
3072 | if (page_mapped(page)) | |
3073 | return; | |
3074 | if (page->mapping && !PageAnon(page)) | |
3075 | return; | |
69029cd5 KH |
3076 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED); |
3077 | } | |
3078 | ||
3079 | void mem_cgroup_uncharge_cache_page(struct page *page) | |
3080 | { | |
3081 | VM_BUG_ON(page_mapped(page)); | |
b7abea96 | 3082 | VM_BUG_ON(page->mapping); |
69029cd5 KH |
3083 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); |
3084 | } | |
3085 | ||
569b846d KH |
3086 | /* |
3087 | * Batch_start/batch_end is called in unmap_page_range/invlidate/trucate. | |
3088 | * In that cases, pages are freed continuously and we can expect pages | |
3089 | * are in the same memcg. All these calls itself limits the number of | |
3090 | * pages freed at once, then uncharge_start/end() is called properly. | |
3091 | * This may be called prural(2) times in a context, | |
3092 | */ | |
3093 | ||
3094 | void mem_cgroup_uncharge_start(void) | |
3095 | { | |
3096 | current->memcg_batch.do_batch++; | |
3097 | /* We can do nest. */ | |
3098 | if (current->memcg_batch.do_batch == 1) { | |
3099 | current->memcg_batch.memcg = NULL; | |
7ffd4ca7 JW |
3100 | current->memcg_batch.nr_pages = 0; |
3101 | current->memcg_batch.memsw_nr_pages = 0; | |
569b846d KH |
3102 | } |
3103 | } | |
3104 | ||
3105 | void mem_cgroup_uncharge_end(void) | |
3106 | { | |
3107 | struct memcg_batch_info *batch = ¤t->memcg_batch; | |
3108 | ||
3109 | if (!batch->do_batch) | |
3110 | return; | |
3111 | ||
3112 | batch->do_batch--; | |
3113 | if (batch->do_batch) /* If stacked, do nothing. */ | |
3114 | return; | |
3115 | ||
3116 | if (!batch->memcg) | |
3117 | return; | |
3118 | /* | |
3119 | * This "batch->memcg" is valid without any css_get/put etc... | |
3120 | * bacause we hide charges behind us. | |
3121 | */ | |
7ffd4ca7 JW |
3122 | if (batch->nr_pages) |
3123 | res_counter_uncharge(&batch->memcg->res, | |
3124 | batch->nr_pages * PAGE_SIZE); | |
3125 | if (batch->memsw_nr_pages) | |
3126 | res_counter_uncharge(&batch->memcg->memsw, | |
3127 | batch->memsw_nr_pages * PAGE_SIZE); | |
3c11ecf4 | 3128 | memcg_oom_recover(batch->memcg); |
569b846d KH |
3129 | /* forget this pointer (for sanity check) */ |
3130 | batch->memcg = NULL; | |
3131 | } | |
3132 | ||
e767e056 | 3133 | #ifdef CONFIG_SWAP |
8c7c6e34 | 3134 | /* |
e767e056 | 3135 | * called after __delete_from_swap_cache() and drop "page" account. |
8c7c6e34 KH |
3136 | * memcg information is recorded to swap_cgroup of "ent" |
3137 | */ | |
8a9478ca KH |
3138 | void |
3139 | mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout) | |
8c7c6e34 KH |
3140 | { |
3141 | struct mem_cgroup *memcg; | |
8a9478ca KH |
3142 | int ctype = MEM_CGROUP_CHARGE_TYPE_SWAPOUT; |
3143 | ||
3144 | if (!swapout) /* this was a swap cache but the swap is unused ! */ | |
3145 | ctype = MEM_CGROUP_CHARGE_TYPE_DROP; | |
3146 | ||
3147 | memcg = __mem_cgroup_uncharge_common(page, ctype); | |
8c7c6e34 | 3148 | |
f75ca962 KH |
3149 | /* |
3150 | * record memcg information, if swapout && memcg != NULL, | |
3151 | * mem_cgroup_get() was called in uncharge(). | |
3152 | */ | |
3153 | if (do_swap_account && swapout && memcg) | |
a3b2d692 | 3154 | swap_cgroup_record(ent, css_id(&memcg->css)); |
8c7c6e34 | 3155 | } |
e767e056 | 3156 | #endif |
8c7c6e34 KH |
3157 | |
3158 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
3159 | /* | |
3160 | * called from swap_entry_free(). remove record in swap_cgroup and | |
3161 | * uncharge "memsw" account. | |
3162 | */ | |
3163 | void mem_cgroup_uncharge_swap(swp_entry_t ent) | |
d13d1443 | 3164 | { |
8c7c6e34 | 3165 | struct mem_cgroup *memcg; |
a3b2d692 | 3166 | unsigned short id; |
8c7c6e34 KH |
3167 | |
3168 | if (!do_swap_account) | |
3169 | return; | |
3170 | ||
a3b2d692 KH |
3171 | id = swap_cgroup_record(ent, 0); |
3172 | rcu_read_lock(); | |
3173 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 3174 | if (memcg) { |
a3b2d692 KH |
3175 | /* |
3176 | * We uncharge this because swap is freed. | |
3177 | * This memcg can be obsolete one. We avoid calling css_tryget | |
3178 | */ | |
0c3e73e8 | 3179 | if (!mem_cgroup_is_root(memcg)) |
4e649152 | 3180 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
0c3e73e8 | 3181 | mem_cgroup_swap_statistics(memcg, false); |
8c7c6e34 KH |
3182 | mem_cgroup_put(memcg); |
3183 | } | |
a3b2d692 | 3184 | rcu_read_unlock(); |
d13d1443 | 3185 | } |
02491447 DN |
3186 | |
3187 | /** | |
3188 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
3189 | * @entry: swap entry to be moved | |
3190 | * @from: mem_cgroup which the entry is moved from | |
3191 | * @to: mem_cgroup which the entry is moved to | |
483c30b5 | 3192 | * @need_fixup: whether we should fixup res_counters and refcounts. |
02491447 DN |
3193 | * |
3194 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
3195 | * as the mem_cgroup's id of @from. | |
3196 | * | |
3197 | * Returns 0 on success, -EINVAL on failure. | |
3198 | * | |
3199 | * The caller must have charged to @to, IOW, called res_counter_charge() about | |
3200 | * both res and memsw, and called css_get(). | |
3201 | */ | |
3202 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
483c30b5 | 3203 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
02491447 DN |
3204 | { |
3205 | unsigned short old_id, new_id; | |
3206 | ||
3207 | old_id = css_id(&from->css); | |
3208 | new_id = css_id(&to->css); | |
3209 | ||
3210 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
02491447 | 3211 | mem_cgroup_swap_statistics(from, false); |
483c30b5 | 3212 | mem_cgroup_swap_statistics(to, true); |
02491447 | 3213 | /* |
483c30b5 DN |
3214 | * This function is only called from task migration context now. |
3215 | * It postpones res_counter and refcount handling till the end | |
3216 | * of task migration(mem_cgroup_clear_mc()) for performance | |
3217 | * improvement. But we cannot postpone mem_cgroup_get(to) | |
3218 | * because if the process that has been moved to @to does | |
3219 | * swap-in, the refcount of @to might be decreased to 0. | |
02491447 | 3220 | */ |
02491447 | 3221 | mem_cgroup_get(to); |
483c30b5 DN |
3222 | if (need_fixup) { |
3223 | if (!mem_cgroup_is_root(from)) | |
3224 | res_counter_uncharge(&from->memsw, PAGE_SIZE); | |
3225 | mem_cgroup_put(from); | |
3226 | /* | |
3227 | * we charged both to->res and to->memsw, so we should | |
3228 | * uncharge to->res. | |
3229 | */ | |
3230 | if (!mem_cgroup_is_root(to)) | |
3231 | res_counter_uncharge(&to->res, PAGE_SIZE); | |
483c30b5 | 3232 | } |
02491447 DN |
3233 | return 0; |
3234 | } | |
3235 | return -EINVAL; | |
3236 | } | |
3237 | #else | |
3238 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
483c30b5 | 3239 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
02491447 DN |
3240 | { |
3241 | return -EINVAL; | |
3242 | } | |
8c7c6e34 | 3243 | #endif |
d13d1443 | 3244 | |
ae41be37 | 3245 | /* |
01b1ae63 KH |
3246 | * Before starting migration, account PAGE_SIZE to mem_cgroup that the old |
3247 | * page belongs to. | |
ae41be37 | 3248 | */ |
ac39cf8c | 3249 | int mem_cgroup_prepare_migration(struct page *page, |
72835c86 | 3250 | struct page *newpage, struct mem_cgroup **memcgp, gfp_t gfp_mask) |
ae41be37 | 3251 | { |
c0ff4b85 | 3252 | struct mem_cgroup *memcg = NULL; |
7ec99d62 | 3253 | struct page_cgroup *pc; |
ac39cf8c | 3254 | enum charge_type ctype; |
e8589cc1 | 3255 | int ret = 0; |
8869b8f6 | 3256 | |
72835c86 | 3257 | *memcgp = NULL; |
56039efa | 3258 | |
ec168510 | 3259 | VM_BUG_ON(PageTransHuge(page)); |
f8d66542 | 3260 | if (mem_cgroup_disabled()) |
4077960e BS |
3261 | return 0; |
3262 | ||
52d4b9ac KH |
3263 | pc = lookup_page_cgroup(page); |
3264 | lock_page_cgroup(pc); | |
3265 | if (PageCgroupUsed(pc)) { | |
c0ff4b85 R |
3266 | memcg = pc->mem_cgroup; |
3267 | css_get(&memcg->css); | |
ac39cf8c AM |
3268 | /* |
3269 | * At migrating an anonymous page, its mapcount goes down | |
3270 | * to 0 and uncharge() will be called. But, even if it's fully | |
3271 | * unmapped, migration may fail and this page has to be | |
3272 | * charged again. We set MIGRATION flag here and delay uncharge | |
3273 | * until end_migration() is called | |
3274 | * | |
3275 | * Corner Case Thinking | |
3276 | * A) | |
3277 | * When the old page was mapped as Anon and it's unmap-and-freed | |
3278 | * while migration was ongoing. | |
3279 | * If unmap finds the old page, uncharge() of it will be delayed | |
3280 | * until end_migration(). If unmap finds a new page, it's | |
3281 | * uncharged when it make mapcount to be 1->0. If unmap code | |
3282 | * finds swap_migration_entry, the new page will not be mapped | |
3283 | * and end_migration() will find it(mapcount==0). | |
3284 | * | |
3285 | * B) | |
3286 | * When the old page was mapped but migraion fails, the kernel | |
3287 | * remaps it. A charge for it is kept by MIGRATION flag even | |
3288 | * if mapcount goes down to 0. We can do remap successfully | |
3289 | * without charging it again. | |
3290 | * | |
3291 | * C) | |
3292 | * The "old" page is under lock_page() until the end of | |
3293 | * migration, so, the old page itself will not be swapped-out. | |
3294 | * If the new page is swapped out before end_migraton, our | |
3295 | * hook to usual swap-out path will catch the event. | |
3296 | */ | |
3297 | if (PageAnon(page)) | |
3298 | SetPageCgroupMigration(pc); | |
e8589cc1 | 3299 | } |
52d4b9ac | 3300 | unlock_page_cgroup(pc); |
ac39cf8c AM |
3301 | /* |
3302 | * If the page is not charged at this point, | |
3303 | * we return here. | |
3304 | */ | |
c0ff4b85 | 3305 | if (!memcg) |
ac39cf8c | 3306 | return 0; |
01b1ae63 | 3307 | |
72835c86 JW |
3308 | *memcgp = memcg; |
3309 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, 1, memcgp, false); | |
c0ff4b85 | 3310 | css_put(&memcg->css);/* drop extra refcnt */ |
72835c86 | 3311 | if (ret || *memcgp == NULL) { |
ac39cf8c AM |
3312 | if (PageAnon(page)) { |
3313 | lock_page_cgroup(pc); | |
3314 | ClearPageCgroupMigration(pc); | |
3315 | unlock_page_cgroup(pc); | |
3316 | /* | |
3317 | * The old page may be fully unmapped while we kept it. | |
3318 | */ | |
3319 | mem_cgroup_uncharge_page(page); | |
3320 | } | |
3321 | return -ENOMEM; | |
e8589cc1 | 3322 | } |
ac39cf8c AM |
3323 | /* |
3324 | * We charge new page before it's used/mapped. So, even if unlock_page() | |
3325 | * is called before end_migration, we can catch all events on this new | |
3326 | * page. In the case new page is migrated but not remapped, new page's | |
3327 | * mapcount will be finally 0 and we call uncharge in end_migration(). | |
3328 | */ | |
3329 | pc = lookup_page_cgroup(newpage); | |
3330 | if (PageAnon(page)) | |
3331 | ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED; | |
3332 | else if (page_is_file_cache(page)) | |
3333 | ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; | |
3334 | else | |
3335 | ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; | |
c0ff4b85 | 3336 | __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype); |
e8589cc1 | 3337 | return ret; |
ae41be37 | 3338 | } |
8869b8f6 | 3339 | |
69029cd5 | 3340 | /* remove redundant charge if migration failed*/ |
c0ff4b85 | 3341 | void mem_cgroup_end_migration(struct mem_cgroup *memcg, |
50de1dd9 | 3342 | struct page *oldpage, struct page *newpage, bool migration_ok) |
ae41be37 | 3343 | { |
ac39cf8c | 3344 | struct page *used, *unused; |
01b1ae63 | 3345 | struct page_cgroup *pc; |
01b1ae63 | 3346 | |
c0ff4b85 | 3347 | if (!memcg) |
01b1ae63 | 3348 | return; |
ac39cf8c | 3349 | /* blocks rmdir() */ |
c0ff4b85 | 3350 | cgroup_exclude_rmdir(&memcg->css); |
50de1dd9 | 3351 | if (!migration_ok) { |
ac39cf8c AM |
3352 | used = oldpage; |
3353 | unused = newpage; | |
01b1ae63 | 3354 | } else { |
ac39cf8c | 3355 | used = newpage; |
01b1ae63 KH |
3356 | unused = oldpage; |
3357 | } | |
69029cd5 | 3358 | /* |
ac39cf8c AM |
3359 | * We disallowed uncharge of pages under migration because mapcount |
3360 | * of the page goes down to zero, temporarly. | |
3361 | * Clear the flag and check the page should be charged. | |
01b1ae63 | 3362 | */ |
ac39cf8c AM |
3363 | pc = lookup_page_cgroup(oldpage); |
3364 | lock_page_cgroup(pc); | |
3365 | ClearPageCgroupMigration(pc); | |
3366 | unlock_page_cgroup(pc); | |
01b1ae63 | 3367 | |
ac39cf8c AM |
3368 | __mem_cgroup_uncharge_common(unused, MEM_CGROUP_CHARGE_TYPE_FORCE); |
3369 | ||
01b1ae63 | 3370 | /* |
ac39cf8c AM |
3371 | * If a page is a file cache, radix-tree replacement is very atomic |
3372 | * and we can skip this check. When it was an Anon page, its mapcount | |
3373 | * goes down to 0. But because we added MIGRATION flage, it's not | |
3374 | * uncharged yet. There are several case but page->mapcount check | |
3375 | * and USED bit check in mem_cgroup_uncharge_page() will do enough | |
3376 | * check. (see prepare_charge() also) | |
69029cd5 | 3377 | */ |
ac39cf8c AM |
3378 | if (PageAnon(used)) |
3379 | mem_cgroup_uncharge_page(used); | |
88703267 | 3380 | /* |
ac39cf8c AM |
3381 | * At migration, we may charge account against cgroup which has no |
3382 | * tasks. | |
88703267 KH |
3383 | * So, rmdir()->pre_destroy() can be called while we do this charge. |
3384 | * In that case, we need to call pre_destroy() again. check it here. | |
3385 | */ | |
c0ff4b85 | 3386 | cgroup_release_and_wakeup_rmdir(&memcg->css); |
ae41be37 | 3387 | } |
78fb7466 | 3388 | |
ab936cbc KH |
3389 | /* |
3390 | * At replace page cache, newpage is not under any memcg but it's on | |
3391 | * LRU. So, this function doesn't touch res_counter but handles LRU | |
3392 | * in correct way. Both pages are locked so we cannot race with uncharge. | |
3393 | */ | |
3394 | void mem_cgroup_replace_page_cache(struct page *oldpage, | |
3395 | struct page *newpage) | |
3396 | { | |
3397 | struct mem_cgroup *memcg; | |
3398 | struct page_cgroup *pc; | |
3399 | struct zone *zone; | |
3400 | enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE; | |
3401 | unsigned long flags; | |
3402 | ||
3403 | if (mem_cgroup_disabled()) | |
3404 | return; | |
3405 | ||
3406 | pc = lookup_page_cgroup(oldpage); | |
3407 | /* fix accounting on old pages */ | |
3408 | lock_page_cgroup(pc); | |
3409 | memcg = pc->mem_cgroup; | |
3410 | mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), -1); | |
3411 | ClearPageCgroupUsed(pc); | |
3412 | unlock_page_cgroup(pc); | |
3413 | ||
3414 | if (PageSwapBacked(oldpage)) | |
3415 | type = MEM_CGROUP_CHARGE_TYPE_SHMEM; | |
3416 | ||
3417 | zone = page_zone(newpage); | |
3418 | pc = lookup_page_cgroup(newpage); | |
3419 | /* | |
3420 | * Even if newpage->mapping was NULL before starting replacement, | |
3421 | * the newpage may be on LRU(or pagevec for LRU) already. We lock | |
3422 | * LRU while we overwrite pc->mem_cgroup. | |
3423 | */ | |
3424 | spin_lock_irqsave(&zone->lru_lock, flags); | |
3425 | if (PageLRU(newpage)) | |
3426 | del_page_from_lru_list(zone, newpage, page_lru(newpage)); | |
3427 | __mem_cgroup_commit_charge(memcg, newpage, 1, pc, type); | |
3428 | if (PageLRU(newpage)) | |
3429 | add_page_to_lru_list(zone, newpage, page_lru(newpage)); | |
3430 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
3431 | } | |
3432 | ||
f212ad7c DN |
3433 | #ifdef CONFIG_DEBUG_VM |
3434 | static struct page_cgroup *lookup_page_cgroup_used(struct page *page) | |
3435 | { | |
3436 | struct page_cgroup *pc; | |
3437 | ||
3438 | pc = lookup_page_cgroup(page); | |
3439 | if (likely(pc) && PageCgroupUsed(pc)) | |
3440 | return pc; | |
3441 | return NULL; | |
3442 | } | |
3443 | ||
3444 | bool mem_cgroup_bad_page_check(struct page *page) | |
3445 | { | |
3446 | if (mem_cgroup_disabled()) | |
3447 | return false; | |
3448 | ||
3449 | return lookup_page_cgroup_used(page) != NULL; | |
3450 | } | |
3451 | ||
3452 | void mem_cgroup_print_bad_page(struct page *page) | |
3453 | { | |
3454 | struct page_cgroup *pc; | |
3455 | ||
3456 | pc = lookup_page_cgroup_used(page); | |
3457 | if (pc) { | |
3458 | int ret = -1; | |
3459 | char *path; | |
3460 | ||
3461 | printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p", | |
3462 | pc, pc->flags, pc->mem_cgroup); | |
3463 | ||
3464 | path = kmalloc(PATH_MAX, GFP_KERNEL); | |
3465 | if (path) { | |
3466 | rcu_read_lock(); | |
3467 | ret = cgroup_path(pc->mem_cgroup->css.cgroup, | |
3468 | path, PATH_MAX); | |
3469 | rcu_read_unlock(); | |
3470 | } | |
3471 | ||
3472 | printk(KERN_CONT "(%s)\n", | |
3473 | (ret < 0) ? "cannot get the path" : path); | |
3474 | kfree(path); | |
3475 | } | |
3476 | } | |
3477 | #endif | |
3478 | ||
8c7c6e34 KH |
3479 | static DEFINE_MUTEX(set_limit_mutex); |
3480 | ||
d38d2a75 | 3481 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
8c7c6e34 | 3482 | unsigned long long val) |
628f4235 | 3483 | { |
81d39c20 | 3484 | int retry_count; |
3c11ecf4 | 3485 | u64 memswlimit, memlimit; |
628f4235 | 3486 | int ret = 0; |
81d39c20 KH |
3487 | int children = mem_cgroup_count_children(memcg); |
3488 | u64 curusage, oldusage; | |
3c11ecf4 | 3489 | int enlarge; |
81d39c20 KH |
3490 | |
3491 | /* | |
3492 | * For keeping hierarchical_reclaim simple, how long we should retry | |
3493 | * is depends on callers. We set our retry-count to be function | |
3494 | * of # of children which we should visit in this loop. | |
3495 | */ | |
3496 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; | |
3497 | ||
3498 | oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); | |
628f4235 | 3499 | |
3c11ecf4 | 3500 | enlarge = 0; |
8c7c6e34 | 3501 | while (retry_count) { |
628f4235 KH |
3502 | if (signal_pending(current)) { |
3503 | ret = -EINTR; | |
3504 | break; | |
3505 | } | |
8c7c6e34 KH |
3506 | /* |
3507 | * Rather than hide all in some function, I do this in | |
3508 | * open coded manner. You see what this really does. | |
c0ff4b85 | 3509 | * We have to guarantee memcg->res.limit < memcg->memsw.limit. |
8c7c6e34 KH |
3510 | */ |
3511 | mutex_lock(&set_limit_mutex); | |
3512 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
3513 | if (memswlimit < val) { | |
3514 | ret = -EINVAL; | |
3515 | mutex_unlock(&set_limit_mutex); | |
628f4235 KH |
3516 | break; |
3517 | } | |
3c11ecf4 KH |
3518 | |
3519 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3520 | if (memlimit < val) | |
3521 | enlarge = 1; | |
3522 | ||
8c7c6e34 | 3523 | ret = res_counter_set_limit(&memcg->res, val); |
22a668d7 KH |
3524 | if (!ret) { |
3525 | if (memswlimit == val) | |
3526 | memcg->memsw_is_minimum = true; | |
3527 | else | |
3528 | memcg->memsw_is_minimum = false; | |
3529 | } | |
8c7c6e34 KH |
3530 | mutex_unlock(&set_limit_mutex); |
3531 | ||
3532 | if (!ret) | |
3533 | break; | |
3534 | ||
5660048c JW |
3535 | mem_cgroup_reclaim(memcg, GFP_KERNEL, |
3536 | MEM_CGROUP_RECLAIM_SHRINK); | |
81d39c20 KH |
3537 | curusage = res_counter_read_u64(&memcg->res, RES_USAGE); |
3538 | /* Usage is reduced ? */ | |
3539 | if (curusage >= oldusage) | |
3540 | retry_count--; | |
3541 | else | |
3542 | oldusage = curusage; | |
8c7c6e34 | 3543 | } |
3c11ecf4 KH |
3544 | if (!ret && enlarge) |
3545 | memcg_oom_recover(memcg); | |
14797e23 | 3546 | |
8c7c6e34 KH |
3547 | return ret; |
3548 | } | |
3549 | ||
338c8431 LZ |
3550 | static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, |
3551 | unsigned long long val) | |
8c7c6e34 | 3552 | { |
81d39c20 | 3553 | int retry_count; |
3c11ecf4 | 3554 | u64 memlimit, memswlimit, oldusage, curusage; |
81d39c20 KH |
3555 | int children = mem_cgroup_count_children(memcg); |
3556 | int ret = -EBUSY; | |
3c11ecf4 | 3557 | int enlarge = 0; |
8c7c6e34 | 3558 | |
81d39c20 KH |
3559 | /* see mem_cgroup_resize_res_limit */ |
3560 | retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; | |
3561 | oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); | |
8c7c6e34 KH |
3562 | while (retry_count) { |
3563 | if (signal_pending(current)) { | |
3564 | ret = -EINTR; | |
3565 | break; | |
3566 | } | |
3567 | /* | |
3568 | * Rather than hide all in some function, I do this in | |
3569 | * open coded manner. You see what this really does. | |
c0ff4b85 | 3570 | * We have to guarantee memcg->res.limit < memcg->memsw.limit. |
8c7c6e34 KH |
3571 | */ |
3572 | mutex_lock(&set_limit_mutex); | |
3573 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3574 | if (memlimit > val) { | |
3575 | ret = -EINVAL; | |
3576 | mutex_unlock(&set_limit_mutex); | |
3577 | break; | |
3578 | } | |
3c11ecf4 KH |
3579 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
3580 | if (memswlimit < val) | |
3581 | enlarge = 1; | |
8c7c6e34 | 3582 | ret = res_counter_set_limit(&memcg->memsw, val); |
22a668d7 KH |
3583 | if (!ret) { |
3584 | if (memlimit == val) | |
3585 | memcg->memsw_is_minimum = true; | |
3586 | else | |
3587 | memcg->memsw_is_minimum = false; | |
3588 | } | |
8c7c6e34 KH |
3589 | mutex_unlock(&set_limit_mutex); |
3590 | ||
3591 | if (!ret) | |
3592 | break; | |
3593 | ||
5660048c JW |
3594 | mem_cgroup_reclaim(memcg, GFP_KERNEL, |
3595 | MEM_CGROUP_RECLAIM_NOSWAP | | |
3596 | MEM_CGROUP_RECLAIM_SHRINK); | |
8c7c6e34 | 3597 | curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); |
81d39c20 | 3598 | /* Usage is reduced ? */ |
8c7c6e34 | 3599 | if (curusage >= oldusage) |
628f4235 | 3600 | retry_count--; |
81d39c20 KH |
3601 | else |
3602 | oldusage = curusage; | |
628f4235 | 3603 | } |
3c11ecf4 KH |
3604 | if (!ret && enlarge) |
3605 | memcg_oom_recover(memcg); | |
628f4235 KH |
3606 | return ret; |
3607 | } | |
3608 | ||
4e416953 | 3609 | unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, |
0ae5e89c YH |
3610 | gfp_t gfp_mask, |
3611 | unsigned long *total_scanned) | |
4e416953 BS |
3612 | { |
3613 | unsigned long nr_reclaimed = 0; | |
3614 | struct mem_cgroup_per_zone *mz, *next_mz = NULL; | |
3615 | unsigned long reclaimed; | |
3616 | int loop = 0; | |
3617 | struct mem_cgroup_tree_per_zone *mctz; | |
ef8745c1 | 3618 | unsigned long long excess; |
0ae5e89c | 3619 | unsigned long nr_scanned; |
4e416953 BS |
3620 | |
3621 | if (order > 0) | |
3622 | return 0; | |
3623 | ||
00918b6a | 3624 | mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone)); |
4e416953 BS |
3625 | /* |
3626 | * This loop can run a while, specially if mem_cgroup's continuously | |
3627 | * keep exceeding their soft limit and putting the system under | |
3628 | * pressure | |
3629 | */ | |
3630 | do { | |
3631 | if (next_mz) | |
3632 | mz = next_mz; | |
3633 | else | |
3634 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
3635 | if (!mz) | |
3636 | break; | |
3637 | ||
0ae5e89c | 3638 | nr_scanned = 0; |
5660048c JW |
3639 | reclaimed = mem_cgroup_soft_reclaim(mz->mem, zone, |
3640 | gfp_mask, &nr_scanned); | |
4e416953 | 3641 | nr_reclaimed += reclaimed; |
0ae5e89c | 3642 | *total_scanned += nr_scanned; |
4e416953 BS |
3643 | spin_lock(&mctz->lock); |
3644 | ||
3645 | /* | |
3646 | * If we failed to reclaim anything from this memory cgroup | |
3647 | * it is time to move on to the next cgroup | |
3648 | */ | |
3649 | next_mz = NULL; | |
3650 | if (!reclaimed) { | |
3651 | do { | |
3652 | /* | |
3653 | * Loop until we find yet another one. | |
3654 | * | |
3655 | * By the time we get the soft_limit lock | |
3656 | * again, someone might have aded the | |
3657 | * group back on the RB tree. Iterate to | |
3658 | * make sure we get a different mem. | |
3659 | * mem_cgroup_largest_soft_limit_node returns | |
3660 | * NULL if no other cgroup is present on | |
3661 | * the tree | |
3662 | */ | |
3663 | next_mz = | |
3664 | __mem_cgroup_largest_soft_limit_node(mctz); | |
39cc98f1 | 3665 | if (next_mz == mz) |
4e416953 | 3666 | css_put(&next_mz->mem->css); |
39cc98f1 | 3667 | else /* next_mz == NULL or other memcg */ |
4e416953 BS |
3668 | break; |
3669 | } while (1); | |
3670 | } | |
4e416953 | 3671 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); |
ef8745c1 | 3672 | excess = res_counter_soft_limit_excess(&mz->mem->res); |
4e416953 BS |
3673 | /* |
3674 | * One school of thought says that we should not add | |
3675 | * back the node to the tree if reclaim returns 0. | |
3676 | * But our reclaim could return 0, simply because due | |
3677 | * to priority we are exposing a smaller subset of | |
3678 | * memory to reclaim from. Consider this as a longer | |
3679 | * term TODO. | |
3680 | */ | |
ef8745c1 KH |
3681 | /* If excess == 0, no tree ops */ |
3682 | __mem_cgroup_insert_exceeded(mz->mem, mz, mctz, excess); | |
4e416953 BS |
3683 | spin_unlock(&mctz->lock); |
3684 | css_put(&mz->mem->css); | |
3685 | loop++; | |
3686 | /* | |
3687 | * Could not reclaim anything and there are no more | |
3688 | * mem cgroups to try or we seem to be looping without | |
3689 | * reclaiming anything. | |
3690 | */ | |
3691 | if (!nr_reclaimed && | |
3692 | (next_mz == NULL || | |
3693 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
3694 | break; | |
3695 | } while (!nr_reclaimed); | |
3696 | if (next_mz) | |
3697 | css_put(&next_mz->mem->css); | |
3698 | return nr_reclaimed; | |
3699 | } | |
3700 | ||
cc847582 KH |
3701 | /* |
3702 | * This routine traverse page_cgroup in given list and drop them all. | |
cc847582 KH |
3703 | * *And* this routine doesn't reclaim page itself, just removes page_cgroup. |
3704 | */ | |
c0ff4b85 | 3705 | static int mem_cgroup_force_empty_list(struct mem_cgroup *memcg, |
08e552c6 | 3706 | int node, int zid, enum lru_list lru) |
cc847582 | 3707 | { |
08e552c6 | 3708 | struct mem_cgroup_per_zone *mz; |
08e552c6 | 3709 | unsigned long flags, loop; |
072c56c1 | 3710 | struct list_head *list; |
925b7673 JW |
3711 | struct page *busy; |
3712 | struct zone *zone; | |
f817ed48 | 3713 | int ret = 0; |
072c56c1 | 3714 | |
08e552c6 | 3715 | zone = &NODE_DATA(node)->node_zones[zid]; |
c0ff4b85 | 3716 | mz = mem_cgroup_zoneinfo(memcg, node, zid); |
6290df54 | 3717 | list = &mz->lruvec.lists[lru]; |
cc847582 | 3718 | |
f817ed48 KH |
3719 | loop = MEM_CGROUP_ZSTAT(mz, lru); |
3720 | /* give some margin against EBUSY etc...*/ | |
3721 | loop += 256; | |
3722 | busy = NULL; | |
3723 | while (loop--) { | |
925b7673 | 3724 | struct page_cgroup *pc; |
5564e88b JW |
3725 | struct page *page; |
3726 | ||
f817ed48 | 3727 | ret = 0; |
08e552c6 | 3728 | spin_lock_irqsave(&zone->lru_lock, flags); |
f817ed48 | 3729 | if (list_empty(list)) { |
08e552c6 | 3730 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
52d4b9ac | 3731 | break; |
f817ed48 | 3732 | } |
925b7673 JW |
3733 | page = list_entry(list->prev, struct page, lru); |
3734 | if (busy == page) { | |
3735 | list_move(&page->lru, list); | |
648bcc77 | 3736 | busy = NULL; |
08e552c6 | 3737 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 KH |
3738 | continue; |
3739 | } | |
08e552c6 | 3740 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 | 3741 | |
925b7673 | 3742 | pc = lookup_page_cgroup(page); |
5564e88b | 3743 | |
c0ff4b85 | 3744 | ret = mem_cgroup_move_parent(page, pc, memcg, GFP_KERNEL); |
f817ed48 | 3745 | if (ret == -ENOMEM) |
52d4b9ac | 3746 | break; |
f817ed48 KH |
3747 | |
3748 | if (ret == -EBUSY || ret == -EINVAL) { | |
3749 | /* found lock contention or "pc" is obsolete. */ | |
925b7673 | 3750 | busy = page; |
f817ed48 KH |
3751 | cond_resched(); |
3752 | } else | |
3753 | busy = NULL; | |
cc847582 | 3754 | } |
08e552c6 | 3755 | |
f817ed48 KH |
3756 | if (!ret && !list_empty(list)) |
3757 | return -EBUSY; | |
3758 | return ret; | |
cc847582 KH |
3759 | } |
3760 | ||
3761 | /* | |
3762 | * make mem_cgroup's charge to be 0 if there is no task. | |
3763 | * This enables deleting this mem_cgroup. | |
3764 | */ | |
c0ff4b85 | 3765 | static int mem_cgroup_force_empty(struct mem_cgroup *memcg, bool free_all) |
cc847582 | 3766 | { |
f817ed48 KH |
3767 | int ret; |
3768 | int node, zid, shrink; | |
3769 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
c0ff4b85 | 3770 | struct cgroup *cgrp = memcg->css.cgroup; |
8869b8f6 | 3771 | |
c0ff4b85 | 3772 | css_get(&memcg->css); |
f817ed48 KH |
3773 | |
3774 | shrink = 0; | |
c1e862c1 KH |
3775 | /* should free all ? */ |
3776 | if (free_all) | |
3777 | goto try_to_free; | |
f817ed48 | 3778 | move_account: |
fce66477 | 3779 | do { |
f817ed48 | 3780 | ret = -EBUSY; |
c1e862c1 KH |
3781 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children)) |
3782 | goto out; | |
3783 | ret = -EINTR; | |
3784 | if (signal_pending(current)) | |
cc847582 | 3785 | goto out; |
52d4b9ac KH |
3786 | /* This is for making all *used* pages to be on LRU. */ |
3787 | lru_add_drain_all(); | |
c0ff4b85 | 3788 | drain_all_stock_sync(memcg); |
f817ed48 | 3789 | ret = 0; |
c0ff4b85 | 3790 | mem_cgroup_start_move(memcg); |
299b4eaa | 3791 | for_each_node_state(node, N_HIGH_MEMORY) { |
f817ed48 | 3792 | for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { |
b69408e8 | 3793 | enum lru_list l; |
f817ed48 | 3794 | for_each_lru(l) { |
c0ff4b85 | 3795 | ret = mem_cgroup_force_empty_list(memcg, |
08e552c6 | 3796 | node, zid, l); |
f817ed48 KH |
3797 | if (ret) |
3798 | break; | |
3799 | } | |
1ecaab2b | 3800 | } |
f817ed48 KH |
3801 | if (ret) |
3802 | break; | |
3803 | } | |
c0ff4b85 R |
3804 | mem_cgroup_end_move(memcg); |
3805 | memcg_oom_recover(memcg); | |
f817ed48 KH |
3806 | /* it seems parent cgroup doesn't have enough mem */ |
3807 | if (ret == -ENOMEM) | |
3808 | goto try_to_free; | |
52d4b9ac | 3809 | cond_resched(); |
fce66477 | 3810 | /* "ret" should also be checked to ensure all lists are empty. */ |
c0ff4b85 | 3811 | } while (memcg->res.usage > 0 || ret); |
cc847582 | 3812 | out: |
c0ff4b85 | 3813 | css_put(&memcg->css); |
cc847582 | 3814 | return ret; |
f817ed48 KH |
3815 | |
3816 | try_to_free: | |
c1e862c1 KH |
3817 | /* returns EBUSY if there is a task or if we come here twice. */ |
3818 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) { | |
f817ed48 KH |
3819 | ret = -EBUSY; |
3820 | goto out; | |
3821 | } | |
c1e862c1 KH |
3822 | /* we call try-to-free pages for make this cgroup empty */ |
3823 | lru_add_drain_all(); | |
f817ed48 KH |
3824 | /* try to free all pages in this cgroup */ |
3825 | shrink = 1; | |
c0ff4b85 | 3826 | while (nr_retries && memcg->res.usage > 0) { |
f817ed48 | 3827 | int progress; |
c1e862c1 KH |
3828 | |
3829 | if (signal_pending(current)) { | |
3830 | ret = -EINTR; | |
3831 | goto out; | |
3832 | } | |
c0ff4b85 | 3833 | progress = try_to_free_mem_cgroup_pages(memcg, GFP_KERNEL, |
185efc0f | 3834 | false); |
c1e862c1 | 3835 | if (!progress) { |
f817ed48 | 3836 | nr_retries--; |
c1e862c1 | 3837 | /* maybe some writeback is necessary */ |
8aa7e847 | 3838 | congestion_wait(BLK_RW_ASYNC, HZ/10); |
c1e862c1 | 3839 | } |
f817ed48 KH |
3840 | |
3841 | } | |
08e552c6 | 3842 | lru_add_drain(); |
f817ed48 | 3843 | /* try move_account...there may be some *locked* pages. */ |
fce66477 | 3844 | goto move_account; |
cc847582 KH |
3845 | } |
3846 | ||
c1e862c1 KH |
3847 | int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event) |
3848 | { | |
3849 | return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true); | |
3850 | } | |
3851 | ||
3852 | ||
18f59ea7 BS |
3853 | static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft) |
3854 | { | |
3855 | return mem_cgroup_from_cont(cont)->use_hierarchy; | |
3856 | } | |
3857 | ||
3858 | static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft, | |
3859 | u64 val) | |
3860 | { | |
3861 | int retval = 0; | |
c0ff4b85 | 3862 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
18f59ea7 | 3863 | struct cgroup *parent = cont->parent; |
c0ff4b85 | 3864 | struct mem_cgroup *parent_memcg = NULL; |
18f59ea7 BS |
3865 | |
3866 | if (parent) | |
c0ff4b85 | 3867 | parent_memcg = mem_cgroup_from_cont(parent); |
18f59ea7 BS |
3868 | |
3869 | cgroup_lock(); | |
3870 | /* | |
af901ca1 | 3871 | * If parent's use_hierarchy is set, we can't make any modifications |
18f59ea7 BS |
3872 | * in the child subtrees. If it is unset, then the change can |
3873 | * occur, provided the current cgroup has no children. | |
3874 | * | |
3875 | * For the root cgroup, parent_mem is NULL, we allow value to be | |
3876 | * set if there are no children. | |
3877 | */ | |
c0ff4b85 | 3878 | if ((!parent_memcg || !parent_memcg->use_hierarchy) && |
18f59ea7 BS |
3879 | (val == 1 || val == 0)) { |
3880 | if (list_empty(&cont->children)) | |
c0ff4b85 | 3881 | memcg->use_hierarchy = val; |
18f59ea7 BS |
3882 | else |
3883 | retval = -EBUSY; | |
3884 | } else | |
3885 | retval = -EINVAL; | |
3886 | cgroup_unlock(); | |
3887 | ||
3888 | return retval; | |
3889 | } | |
3890 | ||
0c3e73e8 | 3891 | |
c0ff4b85 | 3892 | static unsigned long mem_cgroup_recursive_stat(struct mem_cgroup *memcg, |
7a159cc9 | 3893 | enum mem_cgroup_stat_index idx) |
0c3e73e8 | 3894 | { |
7d74b06f | 3895 | struct mem_cgroup *iter; |
7a159cc9 | 3896 | long val = 0; |
0c3e73e8 | 3897 | |
7a159cc9 | 3898 | /* Per-cpu values can be negative, use a signed accumulator */ |
c0ff4b85 | 3899 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f KH |
3900 | val += mem_cgroup_read_stat(iter, idx); |
3901 | ||
3902 | if (val < 0) /* race ? */ | |
3903 | val = 0; | |
3904 | return val; | |
0c3e73e8 BS |
3905 | } |
3906 | ||
c0ff4b85 | 3907 | static inline u64 mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) |
104f3928 | 3908 | { |
7d74b06f | 3909 | u64 val; |
104f3928 | 3910 | |
c0ff4b85 | 3911 | if (!mem_cgroup_is_root(memcg)) { |
104f3928 | 3912 | if (!swap) |
65c64ce8 | 3913 | return res_counter_read_u64(&memcg->res, RES_USAGE); |
104f3928 | 3914 | else |
65c64ce8 | 3915 | return res_counter_read_u64(&memcg->memsw, RES_USAGE); |
104f3928 KS |
3916 | } |
3917 | ||
c0ff4b85 R |
3918 | val = mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_CACHE); |
3919 | val += mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_RSS); | |
104f3928 | 3920 | |
7d74b06f | 3921 | if (swap) |
c0ff4b85 | 3922 | val += mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_SWAPOUT); |
104f3928 KS |
3923 | |
3924 | return val << PAGE_SHIFT; | |
3925 | } | |
3926 | ||
2c3daa72 | 3927 | static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) |
8cdea7c0 | 3928 | { |
c0ff4b85 | 3929 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
104f3928 | 3930 | u64 val; |
8c7c6e34 KH |
3931 | int type, name; |
3932 | ||
3933 | type = MEMFILE_TYPE(cft->private); | |
3934 | name = MEMFILE_ATTR(cft->private); | |
3935 | switch (type) { | |
3936 | case _MEM: | |
104f3928 | 3937 | if (name == RES_USAGE) |
c0ff4b85 | 3938 | val = mem_cgroup_usage(memcg, false); |
104f3928 | 3939 | else |
c0ff4b85 | 3940 | val = res_counter_read_u64(&memcg->res, name); |
8c7c6e34 KH |
3941 | break; |
3942 | case _MEMSWAP: | |
104f3928 | 3943 | if (name == RES_USAGE) |
c0ff4b85 | 3944 | val = mem_cgroup_usage(memcg, true); |
104f3928 | 3945 | else |
c0ff4b85 | 3946 | val = res_counter_read_u64(&memcg->memsw, name); |
8c7c6e34 KH |
3947 | break; |
3948 | default: | |
3949 | BUG(); | |
3950 | break; | |
3951 | } | |
3952 | return val; | |
8cdea7c0 | 3953 | } |
628f4235 KH |
3954 | /* |
3955 | * The user of this function is... | |
3956 | * RES_LIMIT. | |
3957 | */ | |
856c13aa PM |
3958 | static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, |
3959 | const char *buffer) | |
8cdea7c0 | 3960 | { |
628f4235 | 3961 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
8c7c6e34 | 3962 | int type, name; |
628f4235 KH |
3963 | unsigned long long val; |
3964 | int ret; | |
3965 | ||
8c7c6e34 KH |
3966 | type = MEMFILE_TYPE(cft->private); |
3967 | name = MEMFILE_ATTR(cft->private); | |
3968 | switch (name) { | |
628f4235 | 3969 | case RES_LIMIT: |
4b3bde4c BS |
3970 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
3971 | ret = -EINVAL; | |
3972 | break; | |
3973 | } | |
628f4235 KH |
3974 | /* This function does all necessary parse...reuse it */ |
3975 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
8c7c6e34 KH |
3976 | if (ret) |
3977 | break; | |
3978 | if (type == _MEM) | |
628f4235 | 3979 | ret = mem_cgroup_resize_limit(memcg, val); |
8c7c6e34 KH |
3980 | else |
3981 | ret = mem_cgroup_resize_memsw_limit(memcg, val); | |
628f4235 | 3982 | break; |
296c81d8 BS |
3983 | case RES_SOFT_LIMIT: |
3984 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
3985 | if (ret) | |
3986 | break; | |
3987 | /* | |
3988 | * For memsw, soft limits are hard to implement in terms | |
3989 | * of semantics, for now, we support soft limits for | |
3990 | * control without swap | |
3991 | */ | |
3992 | if (type == _MEM) | |
3993 | ret = res_counter_set_soft_limit(&memcg->res, val); | |
3994 | else | |
3995 | ret = -EINVAL; | |
3996 | break; | |
628f4235 KH |
3997 | default: |
3998 | ret = -EINVAL; /* should be BUG() ? */ | |
3999 | break; | |
4000 | } | |
4001 | return ret; | |
8cdea7c0 BS |
4002 | } |
4003 | ||
fee7b548 KH |
4004 | static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, |
4005 | unsigned long long *mem_limit, unsigned long long *memsw_limit) | |
4006 | { | |
4007 | struct cgroup *cgroup; | |
4008 | unsigned long long min_limit, min_memsw_limit, tmp; | |
4009 | ||
4010 | min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
4011 | min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
4012 | cgroup = memcg->css.cgroup; | |
4013 | if (!memcg->use_hierarchy) | |
4014 | goto out; | |
4015 | ||
4016 | while (cgroup->parent) { | |
4017 | cgroup = cgroup->parent; | |
4018 | memcg = mem_cgroup_from_cont(cgroup); | |
4019 | if (!memcg->use_hierarchy) | |
4020 | break; | |
4021 | tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
4022 | min_limit = min(min_limit, tmp); | |
4023 | tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
4024 | min_memsw_limit = min(min_memsw_limit, tmp); | |
4025 | } | |
4026 | out: | |
4027 | *mem_limit = min_limit; | |
4028 | *memsw_limit = min_memsw_limit; | |
4029 | return; | |
4030 | } | |
4031 | ||
29f2a4da | 4032 | static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) |
c84872e1 | 4033 | { |
c0ff4b85 | 4034 | struct mem_cgroup *memcg; |
8c7c6e34 | 4035 | int type, name; |
c84872e1 | 4036 | |
c0ff4b85 | 4037 | memcg = mem_cgroup_from_cont(cont); |
8c7c6e34 KH |
4038 | type = MEMFILE_TYPE(event); |
4039 | name = MEMFILE_ATTR(event); | |
4040 | switch (name) { | |
29f2a4da | 4041 | case RES_MAX_USAGE: |
8c7c6e34 | 4042 | if (type == _MEM) |
c0ff4b85 | 4043 | res_counter_reset_max(&memcg->res); |
8c7c6e34 | 4044 | else |
c0ff4b85 | 4045 | res_counter_reset_max(&memcg->memsw); |
29f2a4da PE |
4046 | break; |
4047 | case RES_FAILCNT: | |
8c7c6e34 | 4048 | if (type == _MEM) |
c0ff4b85 | 4049 | res_counter_reset_failcnt(&memcg->res); |
8c7c6e34 | 4050 | else |
c0ff4b85 | 4051 | res_counter_reset_failcnt(&memcg->memsw); |
29f2a4da PE |
4052 | break; |
4053 | } | |
f64c3f54 | 4054 | |
85cc59db | 4055 | return 0; |
c84872e1 PE |
4056 | } |
4057 | ||
7dc74be0 DN |
4058 | static u64 mem_cgroup_move_charge_read(struct cgroup *cgrp, |
4059 | struct cftype *cft) | |
4060 | { | |
4061 | return mem_cgroup_from_cont(cgrp)->move_charge_at_immigrate; | |
4062 | } | |
4063 | ||
02491447 | 4064 | #ifdef CONFIG_MMU |
7dc74be0 DN |
4065 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, |
4066 | struct cftype *cft, u64 val) | |
4067 | { | |
c0ff4b85 | 4068 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
7dc74be0 DN |
4069 | |
4070 | if (val >= (1 << NR_MOVE_TYPE)) | |
4071 | return -EINVAL; | |
4072 | /* | |
4073 | * We check this value several times in both in can_attach() and | |
4074 | * attach(), so we need cgroup lock to prevent this value from being | |
4075 | * inconsistent. | |
4076 | */ | |
4077 | cgroup_lock(); | |
c0ff4b85 | 4078 | memcg->move_charge_at_immigrate = val; |
7dc74be0 DN |
4079 | cgroup_unlock(); |
4080 | ||
4081 | return 0; | |
4082 | } | |
02491447 DN |
4083 | #else |
4084 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, | |
4085 | struct cftype *cft, u64 val) | |
4086 | { | |
4087 | return -ENOSYS; | |
4088 | } | |
4089 | #endif | |
7dc74be0 | 4090 | |
14067bb3 KH |
4091 | |
4092 | /* For read statistics */ | |
4093 | enum { | |
4094 | MCS_CACHE, | |
4095 | MCS_RSS, | |
d8046582 | 4096 | MCS_FILE_MAPPED, |
14067bb3 KH |
4097 | MCS_PGPGIN, |
4098 | MCS_PGPGOUT, | |
1dd3a273 | 4099 | MCS_SWAP, |
456f998e YH |
4100 | MCS_PGFAULT, |
4101 | MCS_PGMAJFAULT, | |
14067bb3 KH |
4102 | MCS_INACTIVE_ANON, |
4103 | MCS_ACTIVE_ANON, | |
4104 | MCS_INACTIVE_FILE, | |
4105 | MCS_ACTIVE_FILE, | |
4106 | MCS_UNEVICTABLE, | |
4107 | NR_MCS_STAT, | |
4108 | }; | |
4109 | ||
4110 | struct mcs_total_stat { | |
4111 | s64 stat[NR_MCS_STAT]; | |
d2ceb9b7 KH |
4112 | }; |
4113 | ||
14067bb3 KH |
4114 | struct { |
4115 | char *local_name; | |
4116 | char *total_name; | |
4117 | } memcg_stat_strings[NR_MCS_STAT] = { | |
4118 | {"cache", "total_cache"}, | |
4119 | {"rss", "total_rss"}, | |
d69b042f | 4120 | {"mapped_file", "total_mapped_file"}, |
14067bb3 KH |
4121 | {"pgpgin", "total_pgpgin"}, |
4122 | {"pgpgout", "total_pgpgout"}, | |
1dd3a273 | 4123 | {"swap", "total_swap"}, |
456f998e YH |
4124 | {"pgfault", "total_pgfault"}, |
4125 | {"pgmajfault", "total_pgmajfault"}, | |
14067bb3 KH |
4126 | {"inactive_anon", "total_inactive_anon"}, |
4127 | {"active_anon", "total_active_anon"}, | |
4128 | {"inactive_file", "total_inactive_file"}, | |
4129 | {"active_file", "total_active_file"}, | |
4130 | {"unevictable", "total_unevictable"} | |
4131 | }; | |
4132 | ||
4133 | ||
7d74b06f | 4134 | static void |
c0ff4b85 | 4135 | mem_cgroup_get_local_stat(struct mem_cgroup *memcg, struct mcs_total_stat *s) |
14067bb3 | 4136 | { |
14067bb3 KH |
4137 | s64 val; |
4138 | ||
4139 | /* per cpu stat */ | |
c0ff4b85 | 4140 | val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_CACHE); |
14067bb3 | 4141 | s->stat[MCS_CACHE] += val * PAGE_SIZE; |
c0ff4b85 | 4142 | val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_RSS); |
14067bb3 | 4143 | s->stat[MCS_RSS] += val * PAGE_SIZE; |
c0ff4b85 | 4144 | val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_FILE_MAPPED); |
d8046582 | 4145 | s->stat[MCS_FILE_MAPPED] += val * PAGE_SIZE; |
c0ff4b85 | 4146 | val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGPGIN); |
14067bb3 | 4147 | s->stat[MCS_PGPGIN] += val; |
c0ff4b85 | 4148 | val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGPGOUT); |
14067bb3 | 4149 | s->stat[MCS_PGPGOUT] += val; |
1dd3a273 | 4150 | if (do_swap_account) { |
c0ff4b85 | 4151 | val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_SWAPOUT); |
1dd3a273 DN |
4152 | s->stat[MCS_SWAP] += val * PAGE_SIZE; |
4153 | } | |
c0ff4b85 | 4154 | val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGFAULT); |
456f998e | 4155 | s->stat[MCS_PGFAULT] += val; |
c0ff4b85 | 4156 | val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGMAJFAULT); |
456f998e | 4157 | s->stat[MCS_PGMAJFAULT] += val; |
14067bb3 KH |
4158 | |
4159 | /* per zone stat */ | |
c0ff4b85 | 4160 | val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_INACTIVE_ANON)); |
14067bb3 | 4161 | s->stat[MCS_INACTIVE_ANON] += val * PAGE_SIZE; |
c0ff4b85 | 4162 | val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_ACTIVE_ANON)); |
14067bb3 | 4163 | s->stat[MCS_ACTIVE_ANON] += val * PAGE_SIZE; |
c0ff4b85 | 4164 | val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_INACTIVE_FILE)); |
14067bb3 | 4165 | s->stat[MCS_INACTIVE_FILE] += val * PAGE_SIZE; |
c0ff4b85 | 4166 | val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_ACTIVE_FILE)); |
14067bb3 | 4167 | s->stat[MCS_ACTIVE_FILE] += val * PAGE_SIZE; |
c0ff4b85 | 4168 | val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_UNEVICTABLE)); |
14067bb3 | 4169 | s->stat[MCS_UNEVICTABLE] += val * PAGE_SIZE; |
14067bb3 KH |
4170 | } |
4171 | ||
4172 | static void | |
c0ff4b85 | 4173 | mem_cgroup_get_total_stat(struct mem_cgroup *memcg, struct mcs_total_stat *s) |
14067bb3 | 4174 | { |
7d74b06f KH |
4175 | struct mem_cgroup *iter; |
4176 | ||
c0ff4b85 | 4177 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 4178 | mem_cgroup_get_local_stat(iter, s); |
14067bb3 KH |
4179 | } |
4180 | ||
406eb0c9 YH |
4181 | #ifdef CONFIG_NUMA |
4182 | static int mem_control_numa_stat_show(struct seq_file *m, void *arg) | |
4183 | { | |
4184 | int nid; | |
4185 | unsigned long total_nr, file_nr, anon_nr, unevictable_nr; | |
4186 | unsigned long node_nr; | |
4187 | struct cgroup *cont = m->private; | |
4188 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); | |
4189 | ||
bb2a0de9 | 4190 | total_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL); |
406eb0c9 YH |
4191 | seq_printf(m, "total=%lu", total_nr); |
4192 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 | 4193 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, LRU_ALL); |
406eb0c9 YH |
4194 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4195 | } | |
4196 | seq_putc(m, '\n'); | |
4197 | ||
bb2a0de9 | 4198 | file_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL_FILE); |
406eb0c9 YH |
4199 | seq_printf(m, "file=%lu", file_nr); |
4200 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4201 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4202 | LRU_ALL_FILE); | |
406eb0c9 YH |
4203 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4204 | } | |
4205 | seq_putc(m, '\n'); | |
4206 | ||
bb2a0de9 | 4207 | anon_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL_ANON); |
406eb0c9 YH |
4208 | seq_printf(m, "anon=%lu", anon_nr); |
4209 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4210 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4211 | LRU_ALL_ANON); | |
406eb0c9 YH |
4212 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4213 | } | |
4214 | seq_putc(m, '\n'); | |
4215 | ||
bb2a0de9 | 4216 | unevictable_nr = mem_cgroup_nr_lru_pages(mem_cont, BIT(LRU_UNEVICTABLE)); |
406eb0c9 YH |
4217 | seq_printf(m, "unevictable=%lu", unevictable_nr); |
4218 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4219 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4220 | BIT(LRU_UNEVICTABLE)); | |
406eb0c9 YH |
4221 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4222 | } | |
4223 | seq_putc(m, '\n'); | |
4224 | return 0; | |
4225 | } | |
4226 | #endif /* CONFIG_NUMA */ | |
4227 | ||
c64745cf PM |
4228 | static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, |
4229 | struct cgroup_map_cb *cb) | |
d2ceb9b7 | 4230 | { |
d2ceb9b7 | 4231 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); |
14067bb3 | 4232 | struct mcs_total_stat mystat; |
d2ceb9b7 KH |
4233 | int i; |
4234 | ||
14067bb3 KH |
4235 | memset(&mystat, 0, sizeof(mystat)); |
4236 | mem_cgroup_get_local_stat(mem_cont, &mystat); | |
d2ceb9b7 | 4237 | |
406eb0c9 | 4238 | |
1dd3a273 DN |
4239 | for (i = 0; i < NR_MCS_STAT; i++) { |
4240 | if (i == MCS_SWAP && !do_swap_account) | |
4241 | continue; | |
14067bb3 | 4242 | cb->fill(cb, memcg_stat_strings[i].local_name, mystat.stat[i]); |
1dd3a273 | 4243 | } |
7b854121 | 4244 | |
14067bb3 | 4245 | /* Hierarchical information */ |
fee7b548 KH |
4246 | { |
4247 | unsigned long long limit, memsw_limit; | |
4248 | memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit); | |
4249 | cb->fill(cb, "hierarchical_memory_limit", limit); | |
4250 | if (do_swap_account) | |
4251 | cb->fill(cb, "hierarchical_memsw_limit", memsw_limit); | |
4252 | } | |
7f016ee8 | 4253 | |
14067bb3 KH |
4254 | memset(&mystat, 0, sizeof(mystat)); |
4255 | mem_cgroup_get_total_stat(mem_cont, &mystat); | |
1dd3a273 DN |
4256 | for (i = 0; i < NR_MCS_STAT; i++) { |
4257 | if (i == MCS_SWAP && !do_swap_account) | |
4258 | continue; | |
14067bb3 | 4259 | cb->fill(cb, memcg_stat_strings[i].total_name, mystat.stat[i]); |
1dd3a273 | 4260 | } |
14067bb3 | 4261 | |
7f016ee8 | 4262 | #ifdef CONFIG_DEBUG_VM |
7f016ee8 KM |
4263 | { |
4264 | int nid, zid; | |
4265 | struct mem_cgroup_per_zone *mz; | |
4266 | unsigned long recent_rotated[2] = {0, 0}; | |
4267 | unsigned long recent_scanned[2] = {0, 0}; | |
4268 | ||
4269 | for_each_online_node(nid) | |
4270 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
4271 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); | |
4272 | ||
4273 | recent_rotated[0] += | |
4274 | mz->reclaim_stat.recent_rotated[0]; | |
4275 | recent_rotated[1] += | |
4276 | mz->reclaim_stat.recent_rotated[1]; | |
4277 | recent_scanned[0] += | |
4278 | mz->reclaim_stat.recent_scanned[0]; | |
4279 | recent_scanned[1] += | |
4280 | mz->reclaim_stat.recent_scanned[1]; | |
4281 | } | |
4282 | cb->fill(cb, "recent_rotated_anon", recent_rotated[0]); | |
4283 | cb->fill(cb, "recent_rotated_file", recent_rotated[1]); | |
4284 | cb->fill(cb, "recent_scanned_anon", recent_scanned[0]); | |
4285 | cb->fill(cb, "recent_scanned_file", recent_scanned[1]); | |
4286 | } | |
4287 | #endif | |
4288 | ||
d2ceb9b7 KH |
4289 | return 0; |
4290 | } | |
4291 | ||
a7885eb8 KM |
4292 | static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft) |
4293 | { | |
4294 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4295 | ||
1f4c025b | 4296 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
4297 | } |
4298 | ||
4299 | static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, | |
4300 | u64 val) | |
4301 | { | |
4302 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4303 | struct mem_cgroup *parent; | |
068b38c1 | 4304 | |
a7885eb8 KM |
4305 | if (val > 100) |
4306 | return -EINVAL; | |
4307 | ||
4308 | if (cgrp->parent == NULL) | |
4309 | return -EINVAL; | |
4310 | ||
4311 | parent = mem_cgroup_from_cont(cgrp->parent); | |
068b38c1 LZ |
4312 | |
4313 | cgroup_lock(); | |
4314 | ||
a7885eb8 KM |
4315 | /* If under hierarchy, only empty-root can set this value */ |
4316 | if ((parent->use_hierarchy) || | |
068b38c1 LZ |
4317 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
4318 | cgroup_unlock(); | |
a7885eb8 | 4319 | return -EINVAL; |
068b38c1 | 4320 | } |
a7885eb8 | 4321 | |
a7885eb8 | 4322 | memcg->swappiness = val; |
a7885eb8 | 4323 | |
068b38c1 LZ |
4324 | cgroup_unlock(); |
4325 | ||
a7885eb8 KM |
4326 | return 0; |
4327 | } | |
4328 | ||
2e72b634 KS |
4329 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
4330 | { | |
4331 | struct mem_cgroup_threshold_ary *t; | |
4332 | u64 usage; | |
4333 | int i; | |
4334 | ||
4335 | rcu_read_lock(); | |
4336 | if (!swap) | |
2c488db2 | 4337 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 4338 | else |
2c488db2 | 4339 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
4340 | |
4341 | if (!t) | |
4342 | goto unlock; | |
4343 | ||
4344 | usage = mem_cgroup_usage(memcg, swap); | |
4345 | ||
4346 | /* | |
4347 | * current_threshold points to threshold just below usage. | |
4348 | * If it's not true, a threshold was crossed after last | |
4349 | * call of __mem_cgroup_threshold(). | |
4350 | */ | |
5407a562 | 4351 | i = t->current_threshold; |
2e72b634 KS |
4352 | |
4353 | /* | |
4354 | * Iterate backward over array of thresholds starting from | |
4355 | * current_threshold and check if a threshold is crossed. | |
4356 | * If none of thresholds below usage is crossed, we read | |
4357 | * only one element of the array here. | |
4358 | */ | |
4359 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
4360 | eventfd_signal(t->entries[i].eventfd, 1); | |
4361 | ||
4362 | /* i = current_threshold + 1 */ | |
4363 | i++; | |
4364 | ||
4365 | /* | |
4366 | * Iterate forward over array of thresholds starting from | |
4367 | * current_threshold+1 and check if a threshold is crossed. | |
4368 | * If none of thresholds above usage is crossed, we read | |
4369 | * only one element of the array here. | |
4370 | */ | |
4371 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
4372 | eventfd_signal(t->entries[i].eventfd, 1); | |
4373 | ||
4374 | /* Update current_threshold */ | |
5407a562 | 4375 | t->current_threshold = i - 1; |
2e72b634 KS |
4376 | unlock: |
4377 | rcu_read_unlock(); | |
4378 | } | |
4379 | ||
4380 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
4381 | { | |
ad4ca5f4 KS |
4382 | while (memcg) { |
4383 | __mem_cgroup_threshold(memcg, false); | |
4384 | if (do_swap_account) | |
4385 | __mem_cgroup_threshold(memcg, true); | |
4386 | ||
4387 | memcg = parent_mem_cgroup(memcg); | |
4388 | } | |
2e72b634 KS |
4389 | } |
4390 | ||
4391 | static int compare_thresholds(const void *a, const void *b) | |
4392 | { | |
4393 | const struct mem_cgroup_threshold *_a = a; | |
4394 | const struct mem_cgroup_threshold *_b = b; | |
4395 | ||
4396 | return _a->threshold - _b->threshold; | |
4397 | } | |
4398 | ||
c0ff4b85 | 4399 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg) |
9490ff27 KH |
4400 | { |
4401 | struct mem_cgroup_eventfd_list *ev; | |
4402 | ||
c0ff4b85 | 4403 | list_for_each_entry(ev, &memcg->oom_notify, list) |
9490ff27 KH |
4404 | eventfd_signal(ev->eventfd, 1); |
4405 | return 0; | |
4406 | } | |
4407 | ||
c0ff4b85 | 4408 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) |
9490ff27 | 4409 | { |
7d74b06f KH |
4410 | struct mem_cgroup *iter; |
4411 | ||
c0ff4b85 | 4412 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 4413 | mem_cgroup_oom_notify_cb(iter); |
9490ff27 KH |
4414 | } |
4415 | ||
4416 | static int mem_cgroup_usage_register_event(struct cgroup *cgrp, | |
4417 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
2e72b634 KS |
4418 | { |
4419 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4420 | struct mem_cgroup_thresholds *thresholds; |
4421 | struct mem_cgroup_threshold_ary *new; | |
2e72b634 KS |
4422 | int type = MEMFILE_TYPE(cft->private); |
4423 | u64 threshold, usage; | |
2c488db2 | 4424 | int i, size, ret; |
2e72b634 KS |
4425 | |
4426 | ret = res_counter_memparse_write_strategy(args, &threshold); | |
4427 | if (ret) | |
4428 | return ret; | |
4429 | ||
4430 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 4431 | |
2e72b634 | 4432 | if (type == _MEM) |
2c488db2 | 4433 | thresholds = &memcg->thresholds; |
2e72b634 | 4434 | else if (type == _MEMSWAP) |
2c488db2 | 4435 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4436 | else |
4437 | BUG(); | |
4438 | ||
4439 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4440 | ||
4441 | /* Check if a threshold crossed before adding a new one */ | |
2c488db2 | 4442 | if (thresholds->primary) |
2e72b634 KS |
4443 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4444 | ||
2c488db2 | 4445 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
4446 | |
4447 | /* Allocate memory for new array of thresholds */ | |
2c488db2 | 4448 | new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold), |
2e72b634 | 4449 | GFP_KERNEL); |
2c488db2 | 4450 | if (!new) { |
2e72b634 KS |
4451 | ret = -ENOMEM; |
4452 | goto unlock; | |
4453 | } | |
2c488db2 | 4454 | new->size = size; |
2e72b634 KS |
4455 | |
4456 | /* Copy thresholds (if any) to new array */ | |
2c488db2 KS |
4457 | if (thresholds->primary) { |
4458 | memcpy(new->entries, thresholds->primary->entries, (size - 1) * | |
2e72b634 | 4459 | sizeof(struct mem_cgroup_threshold)); |
2c488db2 KS |
4460 | } |
4461 | ||
2e72b634 | 4462 | /* Add new threshold */ |
2c488db2 KS |
4463 | new->entries[size - 1].eventfd = eventfd; |
4464 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
4465 | |
4466 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
2c488db2 | 4467 | sort(new->entries, size, sizeof(struct mem_cgroup_threshold), |
2e72b634 KS |
4468 | compare_thresholds, NULL); |
4469 | ||
4470 | /* Find current threshold */ | |
2c488db2 | 4471 | new->current_threshold = -1; |
2e72b634 | 4472 | for (i = 0; i < size; i++) { |
2c488db2 | 4473 | if (new->entries[i].threshold < usage) { |
2e72b634 | 4474 | /* |
2c488db2 KS |
4475 | * new->current_threshold will not be used until |
4476 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
4477 | * it here. |
4478 | */ | |
2c488db2 | 4479 | ++new->current_threshold; |
2e72b634 KS |
4480 | } |
4481 | } | |
4482 | ||
2c488db2 KS |
4483 | /* Free old spare buffer and save old primary buffer as spare */ |
4484 | kfree(thresholds->spare); | |
4485 | thresholds->spare = thresholds->primary; | |
4486 | ||
4487 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4488 | |
907860ed | 4489 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4490 | synchronize_rcu(); |
4491 | ||
2e72b634 KS |
4492 | unlock: |
4493 | mutex_unlock(&memcg->thresholds_lock); | |
4494 | ||
4495 | return ret; | |
4496 | } | |
4497 | ||
907860ed | 4498 | static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp, |
9490ff27 | 4499 | struct cftype *cft, struct eventfd_ctx *eventfd) |
2e72b634 KS |
4500 | { |
4501 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4502 | struct mem_cgroup_thresholds *thresholds; |
4503 | struct mem_cgroup_threshold_ary *new; | |
2e72b634 KS |
4504 | int type = MEMFILE_TYPE(cft->private); |
4505 | u64 usage; | |
2c488db2 | 4506 | int i, j, size; |
2e72b634 KS |
4507 | |
4508 | mutex_lock(&memcg->thresholds_lock); | |
4509 | if (type == _MEM) | |
2c488db2 | 4510 | thresholds = &memcg->thresholds; |
2e72b634 | 4511 | else if (type == _MEMSWAP) |
2c488db2 | 4512 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4513 | else |
4514 | BUG(); | |
4515 | ||
4516 | /* | |
4517 | * Something went wrong if we trying to unregister a threshold | |
4518 | * if we don't have thresholds | |
4519 | */ | |
4520 | BUG_ON(!thresholds); | |
4521 | ||
4522 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4523 | ||
4524 | /* Check if a threshold crossed before removing */ | |
4525 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
4526 | ||
4527 | /* Calculate new number of threshold */ | |
2c488db2 KS |
4528 | size = 0; |
4529 | for (i = 0; i < thresholds->primary->size; i++) { | |
4530 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 KS |
4531 | size++; |
4532 | } | |
4533 | ||
2c488db2 | 4534 | new = thresholds->spare; |
907860ed | 4535 | |
2e72b634 KS |
4536 | /* Set thresholds array to NULL if we don't have thresholds */ |
4537 | if (!size) { | |
2c488db2 KS |
4538 | kfree(new); |
4539 | new = NULL; | |
907860ed | 4540 | goto swap_buffers; |
2e72b634 KS |
4541 | } |
4542 | ||
2c488db2 | 4543 | new->size = size; |
2e72b634 KS |
4544 | |
4545 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
4546 | new->current_threshold = -1; |
4547 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
4548 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
4549 | continue; |
4550 | ||
2c488db2 KS |
4551 | new->entries[j] = thresholds->primary->entries[i]; |
4552 | if (new->entries[j].threshold < usage) { | |
2e72b634 | 4553 | /* |
2c488db2 | 4554 | * new->current_threshold will not be used |
2e72b634 KS |
4555 | * until rcu_assign_pointer(), so it's safe to increment |
4556 | * it here. | |
4557 | */ | |
2c488db2 | 4558 | ++new->current_threshold; |
2e72b634 KS |
4559 | } |
4560 | j++; | |
4561 | } | |
4562 | ||
907860ed | 4563 | swap_buffers: |
2c488db2 KS |
4564 | /* Swap primary and spare array */ |
4565 | thresholds->spare = thresholds->primary; | |
4566 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4567 | |
907860ed | 4568 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4569 | synchronize_rcu(); |
4570 | ||
2e72b634 | 4571 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 4572 | } |
c1e862c1 | 4573 | |
9490ff27 KH |
4574 | static int mem_cgroup_oom_register_event(struct cgroup *cgrp, |
4575 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
4576 | { | |
4577 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4578 | struct mem_cgroup_eventfd_list *event; | |
4579 | int type = MEMFILE_TYPE(cft->private); | |
4580 | ||
4581 | BUG_ON(type != _OOM_TYPE); | |
4582 | event = kmalloc(sizeof(*event), GFP_KERNEL); | |
4583 | if (!event) | |
4584 | return -ENOMEM; | |
4585 | ||
1af8efe9 | 4586 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4587 | |
4588 | event->eventfd = eventfd; | |
4589 | list_add(&event->list, &memcg->oom_notify); | |
4590 | ||
4591 | /* already in OOM ? */ | |
79dfdacc | 4592 | if (atomic_read(&memcg->under_oom)) |
9490ff27 | 4593 | eventfd_signal(eventfd, 1); |
1af8efe9 | 4594 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4595 | |
4596 | return 0; | |
4597 | } | |
4598 | ||
907860ed | 4599 | static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp, |
9490ff27 KH |
4600 | struct cftype *cft, struct eventfd_ctx *eventfd) |
4601 | { | |
c0ff4b85 | 4602 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
9490ff27 KH |
4603 | struct mem_cgroup_eventfd_list *ev, *tmp; |
4604 | int type = MEMFILE_TYPE(cft->private); | |
4605 | ||
4606 | BUG_ON(type != _OOM_TYPE); | |
4607 | ||
1af8efe9 | 4608 | spin_lock(&memcg_oom_lock); |
9490ff27 | 4609 | |
c0ff4b85 | 4610 | list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) { |
9490ff27 KH |
4611 | if (ev->eventfd == eventfd) { |
4612 | list_del(&ev->list); | |
4613 | kfree(ev); | |
4614 | } | |
4615 | } | |
4616 | ||
1af8efe9 | 4617 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4618 | } |
4619 | ||
3c11ecf4 KH |
4620 | static int mem_cgroup_oom_control_read(struct cgroup *cgrp, |
4621 | struct cftype *cft, struct cgroup_map_cb *cb) | |
4622 | { | |
c0ff4b85 | 4623 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
3c11ecf4 | 4624 | |
c0ff4b85 | 4625 | cb->fill(cb, "oom_kill_disable", memcg->oom_kill_disable); |
3c11ecf4 | 4626 | |
c0ff4b85 | 4627 | if (atomic_read(&memcg->under_oom)) |
3c11ecf4 KH |
4628 | cb->fill(cb, "under_oom", 1); |
4629 | else | |
4630 | cb->fill(cb, "under_oom", 0); | |
4631 | return 0; | |
4632 | } | |
4633 | ||
3c11ecf4 KH |
4634 | static int mem_cgroup_oom_control_write(struct cgroup *cgrp, |
4635 | struct cftype *cft, u64 val) | |
4636 | { | |
c0ff4b85 | 4637 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
3c11ecf4 KH |
4638 | struct mem_cgroup *parent; |
4639 | ||
4640 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
4641 | if (!cgrp->parent || !((val == 0) || (val == 1))) | |
4642 | return -EINVAL; | |
4643 | ||
4644 | parent = mem_cgroup_from_cont(cgrp->parent); | |
4645 | ||
4646 | cgroup_lock(); | |
4647 | /* oom-kill-disable is a flag for subhierarchy. */ | |
4648 | if ((parent->use_hierarchy) || | |
c0ff4b85 | 4649 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
3c11ecf4 KH |
4650 | cgroup_unlock(); |
4651 | return -EINVAL; | |
4652 | } | |
c0ff4b85 | 4653 | memcg->oom_kill_disable = val; |
4d845ebf | 4654 | if (!val) |
c0ff4b85 | 4655 | memcg_oom_recover(memcg); |
3c11ecf4 KH |
4656 | cgroup_unlock(); |
4657 | return 0; | |
4658 | } | |
4659 | ||
406eb0c9 YH |
4660 | #ifdef CONFIG_NUMA |
4661 | static const struct file_operations mem_control_numa_stat_file_operations = { | |
4662 | .read = seq_read, | |
4663 | .llseek = seq_lseek, | |
4664 | .release = single_release, | |
4665 | }; | |
4666 | ||
4667 | static int mem_control_numa_stat_open(struct inode *unused, struct file *file) | |
4668 | { | |
4669 | struct cgroup *cont = file->f_dentry->d_parent->d_fsdata; | |
4670 | ||
4671 | file->f_op = &mem_control_numa_stat_file_operations; | |
4672 | return single_open(file, mem_control_numa_stat_show, cont); | |
4673 | } | |
4674 | #endif /* CONFIG_NUMA */ | |
4675 | ||
e5671dfa | 4676 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM |
e5671dfa GC |
4677 | static int register_kmem_files(struct cgroup *cont, struct cgroup_subsys *ss) |
4678 | { | |
d1a4c0b3 GC |
4679 | /* |
4680 | * Part of this would be better living in a separate allocation | |
4681 | * function, leaving us with just the cgroup tree population work. | |
4682 | * We, however, depend on state such as network's proto_list that | |
4683 | * is only initialized after cgroup creation. I found the less | |
4684 | * cumbersome way to deal with it to defer it all to populate time | |
4685 | */ | |
65c64ce8 | 4686 | return mem_cgroup_sockets_init(cont, ss); |
e5671dfa GC |
4687 | }; |
4688 | ||
d1a4c0b3 GC |
4689 | static void kmem_cgroup_destroy(struct cgroup_subsys *ss, |
4690 | struct cgroup *cont) | |
4691 | { | |
4692 | mem_cgroup_sockets_destroy(cont, ss); | |
4693 | } | |
e5671dfa GC |
4694 | #else |
4695 | static int register_kmem_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4696 | { | |
4697 | return 0; | |
4698 | } | |
d1a4c0b3 GC |
4699 | |
4700 | static void kmem_cgroup_destroy(struct cgroup_subsys *ss, | |
4701 | struct cgroup *cont) | |
4702 | { | |
4703 | } | |
e5671dfa GC |
4704 | #endif |
4705 | ||
8cdea7c0 BS |
4706 | static struct cftype mem_cgroup_files[] = { |
4707 | { | |
0eea1030 | 4708 | .name = "usage_in_bytes", |
8c7c6e34 | 4709 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
2c3daa72 | 4710 | .read_u64 = mem_cgroup_read, |
9490ff27 KH |
4711 | .register_event = mem_cgroup_usage_register_event, |
4712 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8cdea7c0 | 4713 | }, |
c84872e1 PE |
4714 | { |
4715 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 4716 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
29f2a4da | 4717 | .trigger = mem_cgroup_reset, |
c84872e1 PE |
4718 | .read_u64 = mem_cgroup_read, |
4719 | }, | |
8cdea7c0 | 4720 | { |
0eea1030 | 4721 | .name = "limit_in_bytes", |
8c7c6e34 | 4722 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
856c13aa | 4723 | .write_string = mem_cgroup_write, |
2c3daa72 | 4724 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 4725 | }, |
296c81d8 BS |
4726 | { |
4727 | .name = "soft_limit_in_bytes", | |
4728 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
4729 | .write_string = mem_cgroup_write, | |
4730 | .read_u64 = mem_cgroup_read, | |
4731 | }, | |
8cdea7c0 BS |
4732 | { |
4733 | .name = "failcnt", | |
8c7c6e34 | 4734 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
29f2a4da | 4735 | .trigger = mem_cgroup_reset, |
2c3daa72 | 4736 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 4737 | }, |
d2ceb9b7 KH |
4738 | { |
4739 | .name = "stat", | |
c64745cf | 4740 | .read_map = mem_control_stat_show, |
d2ceb9b7 | 4741 | }, |
c1e862c1 KH |
4742 | { |
4743 | .name = "force_empty", | |
4744 | .trigger = mem_cgroup_force_empty_write, | |
4745 | }, | |
18f59ea7 BS |
4746 | { |
4747 | .name = "use_hierarchy", | |
4748 | .write_u64 = mem_cgroup_hierarchy_write, | |
4749 | .read_u64 = mem_cgroup_hierarchy_read, | |
4750 | }, | |
a7885eb8 KM |
4751 | { |
4752 | .name = "swappiness", | |
4753 | .read_u64 = mem_cgroup_swappiness_read, | |
4754 | .write_u64 = mem_cgroup_swappiness_write, | |
4755 | }, | |
7dc74be0 DN |
4756 | { |
4757 | .name = "move_charge_at_immigrate", | |
4758 | .read_u64 = mem_cgroup_move_charge_read, | |
4759 | .write_u64 = mem_cgroup_move_charge_write, | |
4760 | }, | |
9490ff27 KH |
4761 | { |
4762 | .name = "oom_control", | |
3c11ecf4 KH |
4763 | .read_map = mem_cgroup_oom_control_read, |
4764 | .write_u64 = mem_cgroup_oom_control_write, | |
9490ff27 KH |
4765 | .register_event = mem_cgroup_oom_register_event, |
4766 | .unregister_event = mem_cgroup_oom_unregister_event, | |
4767 | .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), | |
4768 | }, | |
406eb0c9 YH |
4769 | #ifdef CONFIG_NUMA |
4770 | { | |
4771 | .name = "numa_stat", | |
4772 | .open = mem_control_numa_stat_open, | |
89577127 | 4773 | .mode = S_IRUGO, |
406eb0c9 YH |
4774 | }, |
4775 | #endif | |
8cdea7c0 BS |
4776 | }; |
4777 | ||
8c7c6e34 KH |
4778 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4779 | static struct cftype memsw_cgroup_files[] = { | |
4780 | { | |
4781 | .name = "memsw.usage_in_bytes", | |
4782 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
4783 | .read_u64 = mem_cgroup_read, | |
9490ff27 KH |
4784 | .register_event = mem_cgroup_usage_register_event, |
4785 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8c7c6e34 KH |
4786 | }, |
4787 | { | |
4788 | .name = "memsw.max_usage_in_bytes", | |
4789 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
4790 | .trigger = mem_cgroup_reset, | |
4791 | .read_u64 = mem_cgroup_read, | |
4792 | }, | |
4793 | { | |
4794 | .name = "memsw.limit_in_bytes", | |
4795 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
4796 | .write_string = mem_cgroup_write, | |
4797 | .read_u64 = mem_cgroup_read, | |
4798 | }, | |
4799 | { | |
4800 | .name = "memsw.failcnt", | |
4801 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
4802 | .trigger = mem_cgroup_reset, | |
4803 | .read_u64 = mem_cgroup_read, | |
4804 | }, | |
4805 | }; | |
4806 | ||
4807 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4808 | { | |
4809 | if (!do_swap_account) | |
4810 | return 0; | |
4811 | return cgroup_add_files(cont, ss, memsw_cgroup_files, | |
4812 | ARRAY_SIZE(memsw_cgroup_files)); | |
4813 | }; | |
4814 | #else | |
4815 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4816 | { | |
4817 | return 0; | |
4818 | } | |
4819 | #endif | |
4820 | ||
c0ff4b85 | 4821 | static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) |
6d12e2d8 KH |
4822 | { |
4823 | struct mem_cgroup_per_node *pn; | |
1ecaab2b | 4824 | struct mem_cgroup_per_zone *mz; |
b69408e8 | 4825 | enum lru_list l; |
41e3355d | 4826 | int zone, tmp = node; |
1ecaab2b KH |
4827 | /* |
4828 | * This routine is called against possible nodes. | |
4829 | * But it's BUG to call kmalloc() against offline node. | |
4830 | * | |
4831 | * TODO: this routine can waste much memory for nodes which will | |
4832 | * never be onlined. It's better to use memory hotplug callback | |
4833 | * function. | |
4834 | */ | |
41e3355d KH |
4835 | if (!node_state(node, N_NORMAL_MEMORY)) |
4836 | tmp = -1; | |
17295c88 | 4837 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); |
6d12e2d8 KH |
4838 | if (!pn) |
4839 | return 1; | |
1ecaab2b | 4840 | |
1ecaab2b KH |
4841 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
4842 | mz = &pn->zoneinfo[zone]; | |
b69408e8 | 4843 | for_each_lru(l) |
6290df54 | 4844 | INIT_LIST_HEAD(&mz->lruvec.lists[l]); |
f64c3f54 | 4845 | mz->usage_in_excess = 0; |
4e416953 | 4846 | mz->on_tree = false; |
c0ff4b85 | 4847 | mz->mem = memcg; |
1ecaab2b | 4848 | } |
0a619e58 | 4849 | memcg->info.nodeinfo[node] = pn; |
6d12e2d8 KH |
4850 | return 0; |
4851 | } | |
4852 | ||
c0ff4b85 | 4853 | static void free_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) |
1ecaab2b | 4854 | { |
c0ff4b85 | 4855 | kfree(memcg->info.nodeinfo[node]); |
1ecaab2b KH |
4856 | } |
4857 | ||
33327948 KH |
4858 | static struct mem_cgroup *mem_cgroup_alloc(void) |
4859 | { | |
4860 | struct mem_cgroup *mem; | |
c62b1a3b | 4861 | int size = sizeof(struct mem_cgroup); |
33327948 | 4862 | |
c62b1a3b | 4863 | /* Can be very big if MAX_NUMNODES is very big */ |
c8dad2bb | 4864 | if (size < PAGE_SIZE) |
17295c88 | 4865 | mem = kzalloc(size, GFP_KERNEL); |
33327948 | 4866 | else |
17295c88 | 4867 | mem = vzalloc(size); |
33327948 | 4868 | |
e7bbcdf3 DC |
4869 | if (!mem) |
4870 | return NULL; | |
4871 | ||
c62b1a3b | 4872 | mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu); |
d2e61b8d DC |
4873 | if (!mem->stat) |
4874 | goto out_free; | |
711d3d2c | 4875 | spin_lock_init(&mem->pcp_counter_lock); |
33327948 | 4876 | return mem; |
d2e61b8d DC |
4877 | |
4878 | out_free: | |
4879 | if (size < PAGE_SIZE) | |
4880 | kfree(mem); | |
4881 | else | |
4882 | vfree(mem); | |
4883 | return NULL; | |
33327948 KH |
4884 | } |
4885 | ||
8c7c6e34 KH |
4886 | /* |
4887 | * At destroying mem_cgroup, references from swap_cgroup can remain. | |
4888 | * (scanning all at force_empty is too costly...) | |
4889 | * | |
4890 | * Instead of clearing all references at force_empty, we remember | |
4891 | * the number of reference from swap_cgroup and free mem_cgroup when | |
4892 | * it goes down to 0. | |
4893 | * | |
8c7c6e34 KH |
4894 | * Removal of cgroup itself succeeds regardless of refs from swap. |
4895 | */ | |
4896 | ||
c0ff4b85 | 4897 | static void __mem_cgroup_free(struct mem_cgroup *memcg) |
33327948 | 4898 | { |
08e552c6 KH |
4899 | int node; |
4900 | ||
c0ff4b85 R |
4901 | mem_cgroup_remove_from_trees(memcg); |
4902 | free_css_id(&mem_cgroup_subsys, &memcg->css); | |
04046e1a | 4903 | |
08e552c6 | 4904 | for_each_node_state(node, N_POSSIBLE) |
c0ff4b85 | 4905 | free_mem_cgroup_per_zone_info(memcg, node); |
08e552c6 | 4906 | |
c0ff4b85 | 4907 | free_percpu(memcg->stat); |
c62b1a3b | 4908 | if (sizeof(struct mem_cgroup) < PAGE_SIZE) |
c0ff4b85 | 4909 | kfree(memcg); |
33327948 | 4910 | else |
c0ff4b85 | 4911 | vfree(memcg); |
33327948 KH |
4912 | } |
4913 | ||
c0ff4b85 | 4914 | static void mem_cgroup_get(struct mem_cgroup *memcg) |
8c7c6e34 | 4915 | { |
c0ff4b85 | 4916 | atomic_inc(&memcg->refcnt); |
8c7c6e34 KH |
4917 | } |
4918 | ||
c0ff4b85 | 4919 | static void __mem_cgroup_put(struct mem_cgroup *memcg, int count) |
8c7c6e34 | 4920 | { |
c0ff4b85 R |
4921 | if (atomic_sub_and_test(count, &memcg->refcnt)) { |
4922 | struct mem_cgroup *parent = parent_mem_cgroup(memcg); | |
4923 | __mem_cgroup_free(memcg); | |
7bcc1bb1 DN |
4924 | if (parent) |
4925 | mem_cgroup_put(parent); | |
4926 | } | |
8c7c6e34 KH |
4927 | } |
4928 | ||
c0ff4b85 | 4929 | static void mem_cgroup_put(struct mem_cgroup *memcg) |
483c30b5 | 4930 | { |
c0ff4b85 | 4931 | __mem_cgroup_put(memcg, 1); |
483c30b5 DN |
4932 | } |
4933 | ||
7bcc1bb1 DN |
4934 | /* |
4935 | * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. | |
4936 | */ | |
e1aab161 | 4937 | struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) |
7bcc1bb1 | 4938 | { |
c0ff4b85 | 4939 | if (!memcg->res.parent) |
7bcc1bb1 | 4940 | return NULL; |
c0ff4b85 | 4941 | return mem_cgroup_from_res_counter(memcg->res.parent, res); |
7bcc1bb1 | 4942 | } |
e1aab161 | 4943 | EXPORT_SYMBOL(parent_mem_cgroup); |
33327948 | 4944 | |
c077719b KH |
4945 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4946 | static void __init enable_swap_cgroup(void) | |
4947 | { | |
f8d66542 | 4948 | if (!mem_cgroup_disabled() && really_do_swap_account) |
c077719b KH |
4949 | do_swap_account = 1; |
4950 | } | |
4951 | #else | |
4952 | static void __init enable_swap_cgroup(void) | |
4953 | { | |
4954 | } | |
4955 | #endif | |
4956 | ||
f64c3f54 BS |
4957 | static int mem_cgroup_soft_limit_tree_init(void) |
4958 | { | |
4959 | struct mem_cgroup_tree_per_node *rtpn; | |
4960 | struct mem_cgroup_tree_per_zone *rtpz; | |
4961 | int tmp, node, zone; | |
4962 | ||
4963 | for_each_node_state(node, N_POSSIBLE) { | |
4964 | tmp = node; | |
4965 | if (!node_state(node, N_NORMAL_MEMORY)) | |
4966 | tmp = -1; | |
4967 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, tmp); | |
4968 | if (!rtpn) | |
4969 | return 1; | |
4970 | ||
4971 | soft_limit_tree.rb_tree_per_node[node] = rtpn; | |
4972 | ||
4973 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
4974 | rtpz = &rtpn->rb_tree_per_zone[zone]; | |
4975 | rtpz->rb_root = RB_ROOT; | |
4976 | spin_lock_init(&rtpz->lock); | |
4977 | } | |
4978 | } | |
4979 | return 0; | |
4980 | } | |
4981 | ||
0eb253e2 | 4982 | static struct cgroup_subsys_state * __ref |
8cdea7c0 BS |
4983 | mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) |
4984 | { | |
c0ff4b85 | 4985 | struct mem_cgroup *memcg, *parent; |
04046e1a | 4986 | long error = -ENOMEM; |
6d12e2d8 | 4987 | int node; |
8cdea7c0 | 4988 | |
c0ff4b85 R |
4989 | memcg = mem_cgroup_alloc(); |
4990 | if (!memcg) | |
04046e1a | 4991 | return ERR_PTR(error); |
78fb7466 | 4992 | |
6d12e2d8 | 4993 | for_each_node_state(node, N_POSSIBLE) |
c0ff4b85 | 4994 | if (alloc_mem_cgroup_per_zone_info(memcg, node)) |
6d12e2d8 | 4995 | goto free_out; |
f64c3f54 | 4996 | |
c077719b | 4997 | /* root ? */ |
28dbc4b6 | 4998 | if (cont->parent == NULL) { |
cdec2e42 | 4999 | int cpu; |
c077719b | 5000 | enable_swap_cgroup(); |
28dbc4b6 | 5001 | parent = NULL; |
f64c3f54 BS |
5002 | if (mem_cgroup_soft_limit_tree_init()) |
5003 | goto free_out; | |
a41c58a6 | 5004 | root_mem_cgroup = memcg; |
cdec2e42 KH |
5005 | for_each_possible_cpu(cpu) { |
5006 | struct memcg_stock_pcp *stock = | |
5007 | &per_cpu(memcg_stock, cpu); | |
5008 | INIT_WORK(&stock->work, drain_local_stock); | |
5009 | } | |
711d3d2c | 5010 | hotcpu_notifier(memcg_cpu_hotplug_callback, 0); |
18f59ea7 | 5011 | } else { |
28dbc4b6 | 5012 | parent = mem_cgroup_from_cont(cont->parent); |
c0ff4b85 R |
5013 | memcg->use_hierarchy = parent->use_hierarchy; |
5014 | memcg->oom_kill_disable = parent->oom_kill_disable; | |
18f59ea7 | 5015 | } |
28dbc4b6 | 5016 | |
18f59ea7 | 5017 | if (parent && parent->use_hierarchy) { |
c0ff4b85 R |
5018 | res_counter_init(&memcg->res, &parent->res); |
5019 | res_counter_init(&memcg->memsw, &parent->memsw); | |
7bcc1bb1 DN |
5020 | /* |
5021 | * We increment refcnt of the parent to ensure that we can | |
5022 | * safely access it on res_counter_charge/uncharge. | |
5023 | * This refcnt will be decremented when freeing this | |
5024 | * mem_cgroup(see mem_cgroup_put). | |
5025 | */ | |
5026 | mem_cgroup_get(parent); | |
18f59ea7 | 5027 | } else { |
c0ff4b85 R |
5028 | res_counter_init(&memcg->res, NULL); |
5029 | res_counter_init(&memcg->memsw, NULL); | |
18f59ea7 | 5030 | } |
c0ff4b85 R |
5031 | memcg->last_scanned_node = MAX_NUMNODES; |
5032 | INIT_LIST_HEAD(&memcg->oom_notify); | |
6d61ef40 | 5033 | |
a7885eb8 | 5034 | if (parent) |
c0ff4b85 R |
5035 | memcg->swappiness = mem_cgroup_swappiness(parent); |
5036 | atomic_set(&memcg->refcnt, 1); | |
5037 | memcg->move_charge_at_immigrate = 0; | |
5038 | mutex_init(&memcg->thresholds_lock); | |
5039 | return &memcg->css; | |
6d12e2d8 | 5040 | free_out: |
c0ff4b85 | 5041 | __mem_cgroup_free(memcg); |
04046e1a | 5042 | return ERR_PTR(error); |
8cdea7c0 BS |
5043 | } |
5044 | ||
ec64f515 | 5045 | static int mem_cgroup_pre_destroy(struct cgroup_subsys *ss, |
df878fb0 KH |
5046 | struct cgroup *cont) |
5047 | { | |
c0ff4b85 | 5048 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
ec64f515 | 5049 | |
c0ff4b85 | 5050 | return mem_cgroup_force_empty(memcg, false); |
df878fb0 KH |
5051 | } |
5052 | ||
8cdea7c0 BS |
5053 | static void mem_cgroup_destroy(struct cgroup_subsys *ss, |
5054 | struct cgroup *cont) | |
5055 | { | |
c0ff4b85 | 5056 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
c268e994 | 5057 | |
d1a4c0b3 GC |
5058 | kmem_cgroup_destroy(ss, cont); |
5059 | ||
c0ff4b85 | 5060 | mem_cgroup_put(memcg); |
8cdea7c0 BS |
5061 | } |
5062 | ||
5063 | static int mem_cgroup_populate(struct cgroup_subsys *ss, | |
5064 | struct cgroup *cont) | |
5065 | { | |
8c7c6e34 KH |
5066 | int ret; |
5067 | ||
5068 | ret = cgroup_add_files(cont, ss, mem_cgroup_files, | |
5069 | ARRAY_SIZE(mem_cgroup_files)); | |
5070 | ||
5071 | if (!ret) | |
5072 | ret = register_memsw_files(cont, ss); | |
e5671dfa GC |
5073 | |
5074 | if (!ret) | |
5075 | ret = register_kmem_files(cont, ss); | |
5076 | ||
8c7c6e34 | 5077 | return ret; |
8cdea7c0 BS |
5078 | } |
5079 | ||
02491447 | 5080 | #ifdef CONFIG_MMU |
7dc74be0 | 5081 | /* Handlers for move charge at task migration. */ |
854ffa8d DN |
5082 | #define PRECHARGE_COUNT_AT_ONCE 256 |
5083 | static int mem_cgroup_do_precharge(unsigned long count) | |
7dc74be0 | 5084 | { |
854ffa8d DN |
5085 | int ret = 0; |
5086 | int batch_count = PRECHARGE_COUNT_AT_ONCE; | |
c0ff4b85 | 5087 | struct mem_cgroup *memcg = mc.to; |
4ffef5fe | 5088 | |
c0ff4b85 | 5089 | if (mem_cgroup_is_root(memcg)) { |
854ffa8d DN |
5090 | mc.precharge += count; |
5091 | /* we don't need css_get for root */ | |
5092 | return ret; | |
5093 | } | |
5094 | /* try to charge at once */ | |
5095 | if (count > 1) { | |
5096 | struct res_counter *dummy; | |
5097 | /* | |
c0ff4b85 | 5098 | * "memcg" cannot be under rmdir() because we've already checked |
854ffa8d DN |
5099 | * by cgroup_lock_live_cgroup() that it is not removed and we |
5100 | * are still under the same cgroup_mutex. So we can postpone | |
5101 | * css_get(). | |
5102 | */ | |
c0ff4b85 | 5103 | if (res_counter_charge(&memcg->res, PAGE_SIZE * count, &dummy)) |
854ffa8d | 5104 | goto one_by_one; |
c0ff4b85 | 5105 | if (do_swap_account && res_counter_charge(&memcg->memsw, |
854ffa8d | 5106 | PAGE_SIZE * count, &dummy)) { |
c0ff4b85 | 5107 | res_counter_uncharge(&memcg->res, PAGE_SIZE * count); |
854ffa8d DN |
5108 | goto one_by_one; |
5109 | } | |
5110 | mc.precharge += count; | |
854ffa8d DN |
5111 | return ret; |
5112 | } | |
5113 | one_by_one: | |
5114 | /* fall back to one by one charge */ | |
5115 | while (count--) { | |
5116 | if (signal_pending(current)) { | |
5117 | ret = -EINTR; | |
5118 | break; | |
5119 | } | |
5120 | if (!batch_count--) { | |
5121 | batch_count = PRECHARGE_COUNT_AT_ONCE; | |
5122 | cond_resched(); | |
5123 | } | |
c0ff4b85 R |
5124 | ret = __mem_cgroup_try_charge(NULL, |
5125 | GFP_KERNEL, 1, &memcg, false); | |
5126 | if (ret || !memcg) | |
854ffa8d DN |
5127 | /* mem_cgroup_clear_mc() will do uncharge later */ |
5128 | return -ENOMEM; | |
5129 | mc.precharge++; | |
5130 | } | |
4ffef5fe DN |
5131 | return ret; |
5132 | } | |
5133 | ||
5134 | /** | |
5135 | * is_target_pte_for_mc - check a pte whether it is valid for move charge | |
5136 | * @vma: the vma the pte to be checked belongs | |
5137 | * @addr: the address corresponding to the pte to be checked | |
5138 | * @ptent: the pte to be checked | |
02491447 | 5139 | * @target: the pointer the target page or swap ent will be stored(can be NULL) |
4ffef5fe DN |
5140 | * |
5141 | * Returns | |
5142 | * 0(MC_TARGET_NONE): if the pte is not a target for move charge. | |
5143 | * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for | |
5144 | * move charge. if @target is not NULL, the page is stored in target->page | |
5145 | * with extra refcnt got(Callers should handle it). | |
02491447 DN |
5146 | * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a |
5147 | * target for charge migration. if @target is not NULL, the entry is stored | |
5148 | * in target->ent. | |
4ffef5fe DN |
5149 | * |
5150 | * Called with pte lock held. | |
5151 | */ | |
4ffef5fe DN |
5152 | union mc_target { |
5153 | struct page *page; | |
02491447 | 5154 | swp_entry_t ent; |
4ffef5fe DN |
5155 | }; |
5156 | ||
4ffef5fe DN |
5157 | enum mc_target_type { |
5158 | MC_TARGET_NONE, /* not used */ | |
5159 | MC_TARGET_PAGE, | |
02491447 | 5160 | MC_TARGET_SWAP, |
4ffef5fe DN |
5161 | }; |
5162 | ||
90254a65 DN |
5163 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
5164 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 5165 | { |
90254a65 | 5166 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 5167 | |
90254a65 DN |
5168 | if (!page || !page_mapped(page)) |
5169 | return NULL; | |
5170 | if (PageAnon(page)) { | |
5171 | /* we don't move shared anon */ | |
5172 | if (!move_anon() || page_mapcount(page) > 2) | |
5173 | return NULL; | |
87946a72 DN |
5174 | } else if (!move_file()) |
5175 | /* we ignore mapcount for file pages */ | |
90254a65 DN |
5176 | return NULL; |
5177 | if (!get_page_unless_zero(page)) | |
5178 | return NULL; | |
5179 | ||
5180 | return page; | |
5181 | } | |
5182 | ||
5183 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
5184 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5185 | { | |
5186 | int usage_count; | |
5187 | struct page *page = NULL; | |
5188 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
5189 | ||
5190 | if (!move_anon() || non_swap_entry(ent)) | |
5191 | return NULL; | |
5192 | usage_count = mem_cgroup_count_swap_user(ent, &page); | |
5193 | if (usage_count > 1) { /* we don't move shared anon */ | |
02491447 DN |
5194 | if (page) |
5195 | put_page(page); | |
90254a65 | 5196 | return NULL; |
02491447 | 5197 | } |
90254a65 DN |
5198 | if (do_swap_account) |
5199 | entry->val = ent.val; | |
5200 | ||
5201 | return page; | |
5202 | } | |
5203 | ||
87946a72 DN |
5204 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
5205 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5206 | { | |
5207 | struct page *page = NULL; | |
5208 | struct inode *inode; | |
5209 | struct address_space *mapping; | |
5210 | pgoff_t pgoff; | |
5211 | ||
5212 | if (!vma->vm_file) /* anonymous vma */ | |
5213 | return NULL; | |
5214 | if (!move_file()) | |
5215 | return NULL; | |
5216 | ||
5217 | inode = vma->vm_file->f_path.dentry->d_inode; | |
5218 | mapping = vma->vm_file->f_mapping; | |
5219 | if (pte_none(ptent)) | |
5220 | pgoff = linear_page_index(vma, addr); | |
5221 | else /* pte_file(ptent) is true */ | |
5222 | pgoff = pte_to_pgoff(ptent); | |
5223 | ||
5224 | /* page is moved even if it's not RSS of this task(page-faulted). */ | |
aa3b1895 HD |
5225 | page = find_get_page(mapping, pgoff); |
5226 | ||
5227 | #ifdef CONFIG_SWAP | |
5228 | /* shmem/tmpfs may report page out on swap: account for that too. */ | |
5229 | if (radix_tree_exceptional_entry(page)) { | |
5230 | swp_entry_t swap = radix_to_swp_entry(page); | |
87946a72 | 5231 | if (do_swap_account) |
aa3b1895 HD |
5232 | *entry = swap; |
5233 | page = find_get_page(&swapper_space, swap.val); | |
87946a72 | 5234 | } |
aa3b1895 | 5235 | #endif |
87946a72 DN |
5236 | return page; |
5237 | } | |
5238 | ||
90254a65 DN |
5239 | static int is_target_pte_for_mc(struct vm_area_struct *vma, |
5240 | unsigned long addr, pte_t ptent, union mc_target *target) | |
5241 | { | |
5242 | struct page *page = NULL; | |
5243 | struct page_cgroup *pc; | |
5244 | int ret = 0; | |
5245 | swp_entry_t ent = { .val = 0 }; | |
5246 | ||
5247 | if (pte_present(ptent)) | |
5248 | page = mc_handle_present_pte(vma, addr, ptent); | |
5249 | else if (is_swap_pte(ptent)) | |
5250 | page = mc_handle_swap_pte(vma, addr, ptent, &ent); | |
87946a72 DN |
5251 | else if (pte_none(ptent) || pte_file(ptent)) |
5252 | page = mc_handle_file_pte(vma, addr, ptent, &ent); | |
90254a65 DN |
5253 | |
5254 | if (!page && !ent.val) | |
5255 | return 0; | |
02491447 DN |
5256 | if (page) { |
5257 | pc = lookup_page_cgroup(page); | |
5258 | /* | |
5259 | * Do only loose check w/o page_cgroup lock. | |
5260 | * mem_cgroup_move_account() checks the pc is valid or not under | |
5261 | * the lock. | |
5262 | */ | |
5263 | if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { | |
5264 | ret = MC_TARGET_PAGE; | |
5265 | if (target) | |
5266 | target->page = page; | |
5267 | } | |
5268 | if (!ret || !target) | |
5269 | put_page(page); | |
5270 | } | |
90254a65 DN |
5271 | /* There is a swap entry and a page doesn't exist or isn't charged */ |
5272 | if (ent.val && !ret && | |
7f0f1546 KH |
5273 | css_id(&mc.from->css) == lookup_swap_cgroup(ent)) { |
5274 | ret = MC_TARGET_SWAP; | |
5275 | if (target) | |
5276 | target->ent = ent; | |
4ffef5fe | 5277 | } |
4ffef5fe DN |
5278 | return ret; |
5279 | } | |
5280 | ||
5281 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, | |
5282 | unsigned long addr, unsigned long end, | |
5283 | struct mm_walk *walk) | |
5284 | { | |
5285 | struct vm_area_struct *vma = walk->private; | |
5286 | pte_t *pte; | |
5287 | spinlock_t *ptl; | |
5288 | ||
03319327 DH |
5289 | split_huge_page_pmd(walk->mm, pmd); |
5290 | ||
4ffef5fe DN |
5291 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
5292 | for (; addr != end; pte++, addr += PAGE_SIZE) | |
5293 | if (is_target_pte_for_mc(vma, addr, *pte, NULL)) | |
5294 | mc.precharge++; /* increment precharge temporarily */ | |
5295 | pte_unmap_unlock(pte - 1, ptl); | |
5296 | cond_resched(); | |
5297 | ||
7dc74be0 DN |
5298 | return 0; |
5299 | } | |
5300 | ||
4ffef5fe DN |
5301 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
5302 | { | |
5303 | unsigned long precharge; | |
5304 | struct vm_area_struct *vma; | |
5305 | ||
dfe076b0 | 5306 | down_read(&mm->mmap_sem); |
4ffef5fe DN |
5307 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5308 | struct mm_walk mem_cgroup_count_precharge_walk = { | |
5309 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
5310 | .mm = mm, | |
5311 | .private = vma, | |
5312 | }; | |
5313 | if (is_vm_hugetlb_page(vma)) | |
5314 | continue; | |
4ffef5fe DN |
5315 | walk_page_range(vma->vm_start, vma->vm_end, |
5316 | &mem_cgroup_count_precharge_walk); | |
5317 | } | |
dfe076b0 | 5318 | up_read(&mm->mmap_sem); |
4ffef5fe DN |
5319 | |
5320 | precharge = mc.precharge; | |
5321 | mc.precharge = 0; | |
5322 | ||
5323 | return precharge; | |
5324 | } | |
5325 | ||
4ffef5fe DN |
5326 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
5327 | { | |
dfe076b0 DN |
5328 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
5329 | ||
5330 | VM_BUG_ON(mc.moving_task); | |
5331 | mc.moving_task = current; | |
5332 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
5333 | } |
5334 | ||
dfe076b0 DN |
5335 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
5336 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 5337 | { |
2bd9bb20 KH |
5338 | struct mem_cgroup *from = mc.from; |
5339 | struct mem_cgroup *to = mc.to; | |
5340 | ||
4ffef5fe | 5341 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d DN |
5342 | if (mc.precharge) { |
5343 | __mem_cgroup_cancel_charge(mc.to, mc.precharge); | |
5344 | mc.precharge = 0; | |
5345 | } | |
5346 | /* | |
5347 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
5348 | * we must uncharge here. | |
5349 | */ | |
5350 | if (mc.moved_charge) { | |
5351 | __mem_cgroup_cancel_charge(mc.from, mc.moved_charge); | |
5352 | mc.moved_charge = 0; | |
4ffef5fe | 5353 | } |
483c30b5 DN |
5354 | /* we must fixup refcnts and charges */ |
5355 | if (mc.moved_swap) { | |
483c30b5 DN |
5356 | /* uncharge swap account from the old cgroup */ |
5357 | if (!mem_cgroup_is_root(mc.from)) | |
5358 | res_counter_uncharge(&mc.from->memsw, | |
5359 | PAGE_SIZE * mc.moved_swap); | |
5360 | __mem_cgroup_put(mc.from, mc.moved_swap); | |
5361 | ||
5362 | if (!mem_cgroup_is_root(mc.to)) { | |
5363 | /* | |
5364 | * we charged both to->res and to->memsw, so we should | |
5365 | * uncharge to->res. | |
5366 | */ | |
5367 | res_counter_uncharge(&mc.to->res, | |
5368 | PAGE_SIZE * mc.moved_swap); | |
483c30b5 DN |
5369 | } |
5370 | /* we've already done mem_cgroup_get(mc.to) */ | |
483c30b5 DN |
5371 | mc.moved_swap = 0; |
5372 | } | |
dfe076b0 DN |
5373 | memcg_oom_recover(from); |
5374 | memcg_oom_recover(to); | |
5375 | wake_up_all(&mc.waitq); | |
5376 | } | |
5377 | ||
5378 | static void mem_cgroup_clear_mc(void) | |
5379 | { | |
5380 | struct mem_cgroup *from = mc.from; | |
5381 | ||
5382 | /* | |
5383 | * we must clear moving_task before waking up waiters at the end of | |
5384 | * task migration. | |
5385 | */ | |
5386 | mc.moving_task = NULL; | |
5387 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 5388 | spin_lock(&mc.lock); |
4ffef5fe DN |
5389 | mc.from = NULL; |
5390 | mc.to = NULL; | |
2bd9bb20 | 5391 | spin_unlock(&mc.lock); |
32047e2a | 5392 | mem_cgroup_end_move(from); |
4ffef5fe DN |
5393 | } |
5394 | ||
7dc74be0 DN |
5395 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, |
5396 | struct cgroup *cgroup, | |
2f7ee569 | 5397 | struct cgroup_taskset *tset) |
7dc74be0 | 5398 | { |
2f7ee569 | 5399 | struct task_struct *p = cgroup_taskset_first(tset); |
7dc74be0 | 5400 | int ret = 0; |
c0ff4b85 | 5401 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgroup); |
7dc74be0 | 5402 | |
c0ff4b85 | 5403 | if (memcg->move_charge_at_immigrate) { |
7dc74be0 DN |
5404 | struct mm_struct *mm; |
5405 | struct mem_cgroup *from = mem_cgroup_from_task(p); | |
5406 | ||
c0ff4b85 | 5407 | VM_BUG_ON(from == memcg); |
7dc74be0 DN |
5408 | |
5409 | mm = get_task_mm(p); | |
5410 | if (!mm) | |
5411 | return 0; | |
7dc74be0 | 5412 | /* We move charges only when we move a owner of the mm */ |
4ffef5fe DN |
5413 | if (mm->owner == p) { |
5414 | VM_BUG_ON(mc.from); | |
5415 | VM_BUG_ON(mc.to); | |
5416 | VM_BUG_ON(mc.precharge); | |
854ffa8d | 5417 | VM_BUG_ON(mc.moved_charge); |
483c30b5 | 5418 | VM_BUG_ON(mc.moved_swap); |
32047e2a | 5419 | mem_cgroup_start_move(from); |
2bd9bb20 | 5420 | spin_lock(&mc.lock); |
4ffef5fe | 5421 | mc.from = from; |
c0ff4b85 | 5422 | mc.to = memcg; |
2bd9bb20 | 5423 | spin_unlock(&mc.lock); |
dfe076b0 | 5424 | /* We set mc.moving_task later */ |
4ffef5fe DN |
5425 | |
5426 | ret = mem_cgroup_precharge_mc(mm); | |
5427 | if (ret) | |
5428 | mem_cgroup_clear_mc(); | |
dfe076b0 DN |
5429 | } |
5430 | mmput(mm); | |
7dc74be0 DN |
5431 | } |
5432 | return ret; | |
5433 | } | |
5434 | ||
5435 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, | |
5436 | struct cgroup *cgroup, | |
2f7ee569 | 5437 | struct cgroup_taskset *tset) |
7dc74be0 | 5438 | { |
4ffef5fe | 5439 | mem_cgroup_clear_mc(); |
7dc74be0 DN |
5440 | } |
5441 | ||
4ffef5fe DN |
5442 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
5443 | unsigned long addr, unsigned long end, | |
5444 | struct mm_walk *walk) | |
7dc74be0 | 5445 | { |
4ffef5fe DN |
5446 | int ret = 0; |
5447 | struct vm_area_struct *vma = walk->private; | |
5448 | pte_t *pte; | |
5449 | spinlock_t *ptl; | |
5450 | ||
03319327 | 5451 | split_huge_page_pmd(walk->mm, pmd); |
4ffef5fe DN |
5452 | retry: |
5453 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
5454 | for (; addr != end; addr += PAGE_SIZE) { | |
5455 | pte_t ptent = *(pte++); | |
5456 | union mc_target target; | |
5457 | int type; | |
5458 | struct page *page; | |
5459 | struct page_cgroup *pc; | |
02491447 | 5460 | swp_entry_t ent; |
4ffef5fe DN |
5461 | |
5462 | if (!mc.precharge) | |
5463 | break; | |
5464 | ||
5465 | type = is_target_pte_for_mc(vma, addr, ptent, &target); | |
5466 | switch (type) { | |
5467 | case MC_TARGET_PAGE: | |
5468 | page = target.page; | |
5469 | if (isolate_lru_page(page)) | |
5470 | goto put; | |
5471 | pc = lookup_page_cgroup(page); | |
7ec99d62 JW |
5472 | if (!mem_cgroup_move_account(page, 1, pc, |
5473 | mc.from, mc.to, false)) { | |
4ffef5fe | 5474 | mc.precharge--; |
854ffa8d DN |
5475 | /* we uncharge from mc.from later. */ |
5476 | mc.moved_charge++; | |
4ffef5fe DN |
5477 | } |
5478 | putback_lru_page(page); | |
5479 | put: /* is_target_pte_for_mc() gets the page */ | |
5480 | put_page(page); | |
5481 | break; | |
02491447 DN |
5482 | case MC_TARGET_SWAP: |
5483 | ent = target.ent; | |
483c30b5 DN |
5484 | if (!mem_cgroup_move_swap_account(ent, |
5485 | mc.from, mc.to, false)) { | |
02491447 | 5486 | mc.precharge--; |
483c30b5 DN |
5487 | /* we fixup refcnts and charges later. */ |
5488 | mc.moved_swap++; | |
5489 | } | |
02491447 | 5490 | break; |
4ffef5fe DN |
5491 | default: |
5492 | break; | |
5493 | } | |
5494 | } | |
5495 | pte_unmap_unlock(pte - 1, ptl); | |
5496 | cond_resched(); | |
5497 | ||
5498 | if (addr != end) { | |
5499 | /* | |
5500 | * We have consumed all precharges we got in can_attach(). | |
5501 | * We try charge one by one, but don't do any additional | |
5502 | * charges to mc.to if we have failed in charge once in attach() | |
5503 | * phase. | |
5504 | */ | |
854ffa8d | 5505 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
5506 | if (!ret) |
5507 | goto retry; | |
5508 | } | |
5509 | ||
5510 | return ret; | |
5511 | } | |
5512 | ||
5513 | static void mem_cgroup_move_charge(struct mm_struct *mm) | |
5514 | { | |
5515 | struct vm_area_struct *vma; | |
5516 | ||
5517 | lru_add_drain_all(); | |
dfe076b0 DN |
5518 | retry: |
5519 | if (unlikely(!down_read_trylock(&mm->mmap_sem))) { | |
5520 | /* | |
5521 | * Someone who are holding the mmap_sem might be waiting in | |
5522 | * waitq. So we cancel all extra charges, wake up all waiters, | |
5523 | * and retry. Because we cancel precharges, we might not be able | |
5524 | * to move enough charges, but moving charge is a best-effort | |
5525 | * feature anyway, so it wouldn't be a big problem. | |
5526 | */ | |
5527 | __mem_cgroup_clear_mc(); | |
5528 | cond_resched(); | |
5529 | goto retry; | |
5530 | } | |
4ffef5fe DN |
5531 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5532 | int ret; | |
5533 | struct mm_walk mem_cgroup_move_charge_walk = { | |
5534 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
5535 | .mm = mm, | |
5536 | .private = vma, | |
5537 | }; | |
5538 | if (is_vm_hugetlb_page(vma)) | |
5539 | continue; | |
4ffef5fe DN |
5540 | ret = walk_page_range(vma->vm_start, vma->vm_end, |
5541 | &mem_cgroup_move_charge_walk); | |
5542 | if (ret) | |
5543 | /* | |
5544 | * means we have consumed all precharges and failed in | |
5545 | * doing additional charge. Just abandon here. | |
5546 | */ | |
5547 | break; | |
5548 | } | |
dfe076b0 | 5549 | up_read(&mm->mmap_sem); |
7dc74be0 DN |
5550 | } |
5551 | ||
67e465a7 BS |
5552 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, |
5553 | struct cgroup *cont, | |
2f7ee569 | 5554 | struct cgroup_taskset *tset) |
67e465a7 | 5555 | { |
2f7ee569 | 5556 | struct task_struct *p = cgroup_taskset_first(tset); |
a433658c | 5557 | struct mm_struct *mm = get_task_mm(p); |
dfe076b0 | 5558 | |
dfe076b0 | 5559 | if (mm) { |
a433658c KM |
5560 | if (mc.to) |
5561 | mem_cgroup_move_charge(mm); | |
5562 | put_swap_token(mm); | |
dfe076b0 DN |
5563 | mmput(mm); |
5564 | } | |
a433658c KM |
5565 | if (mc.to) |
5566 | mem_cgroup_clear_mc(); | |
67e465a7 | 5567 | } |
5cfb80a7 DN |
5568 | #else /* !CONFIG_MMU */ |
5569 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, | |
5570 | struct cgroup *cgroup, | |
2f7ee569 | 5571 | struct cgroup_taskset *tset) |
5cfb80a7 DN |
5572 | { |
5573 | return 0; | |
5574 | } | |
5575 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, | |
5576 | struct cgroup *cgroup, | |
2f7ee569 | 5577 | struct cgroup_taskset *tset) |
5cfb80a7 DN |
5578 | { |
5579 | } | |
5580 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, | |
5581 | struct cgroup *cont, | |
2f7ee569 | 5582 | struct cgroup_taskset *tset) |
5cfb80a7 DN |
5583 | { |
5584 | } | |
5585 | #endif | |
67e465a7 | 5586 | |
8cdea7c0 BS |
5587 | struct cgroup_subsys mem_cgroup_subsys = { |
5588 | .name = "memory", | |
5589 | .subsys_id = mem_cgroup_subsys_id, | |
5590 | .create = mem_cgroup_create, | |
df878fb0 | 5591 | .pre_destroy = mem_cgroup_pre_destroy, |
8cdea7c0 BS |
5592 | .destroy = mem_cgroup_destroy, |
5593 | .populate = mem_cgroup_populate, | |
7dc74be0 DN |
5594 | .can_attach = mem_cgroup_can_attach, |
5595 | .cancel_attach = mem_cgroup_cancel_attach, | |
67e465a7 | 5596 | .attach = mem_cgroup_move_task, |
6d12e2d8 | 5597 | .early_init = 0, |
04046e1a | 5598 | .use_id = 1, |
8cdea7c0 | 5599 | }; |
c077719b KH |
5600 | |
5601 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
a42c390c MH |
5602 | static int __init enable_swap_account(char *s) |
5603 | { | |
5604 | /* consider enabled if no parameter or 1 is given */ | |
a2c8990a | 5605 | if (!strcmp(s, "1")) |
a42c390c | 5606 | really_do_swap_account = 1; |
a2c8990a | 5607 | else if (!strcmp(s, "0")) |
a42c390c MH |
5608 | really_do_swap_account = 0; |
5609 | return 1; | |
5610 | } | |
a2c8990a | 5611 | __setup("swapaccount=", enable_swap_account); |
c077719b | 5612 | |
c077719b | 5613 | #endif |