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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 { |
072c56c1 KH |
137 | /* |
138 | * spin_lock to protect the per cgroup LRU | |
139 | */ | |
b69408e8 CL |
140 | struct list_head lists[NR_LRU_LISTS]; |
141 | unsigned long count[NR_LRU_LISTS]; | |
3e2f41f1 | 142 | |
527a5ec9 JW |
143 | struct mem_cgroup_reclaim_iter reclaim_iter[DEF_PRIORITY + 1]; |
144 | ||
3e2f41f1 | 145 | struct zone_reclaim_stat reclaim_stat; |
f64c3f54 BS |
146 | struct rb_node tree_node; /* RB tree node */ |
147 | unsigned long long usage_in_excess;/* Set to the value by which */ | |
148 | /* the soft limit is exceeded*/ | |
149 | bool on_tree; | |
4e416953 BS |
150 | struct mem_cgroup *mem; /* Back pointer, we cannot */ |
151 | /* use container_of */ | |
6d12e2d8 KH |
152 | }; |
153 | /* Macro for accessing counter */ | |
154 | #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)]) | |
155 | ||
156 | struct mem_cgroup_per_node { | |
157 | struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES]; | |
158 | }; | |
159 | ||
160 | struct mem_cgroup_lru_info { | |
161 | struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES]; | |
162 | }; | |
163 | ||
f64c3f54 BS |
164 | /* |
165 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
166 | * their hierarchy representation | |
167 | */ | |
168 | ||
169 | struct mem_cgroup_tree_per_zone { | |
170 | struct rb_root rb_root; | |
171 | spinlock_t lock; | |
172 | }; | |
173 | ||
174 | struct mem_cgroup_tree_per_node { | |
175 | struct mem_cgroup_tree_per_zone rb_tree_per_zone[MAX_NR_ZONES]; | |
176 | }; | |
177 | ||
178 | struct mem_cgroup_tree { | |
179 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
180 | }; | |
181 | ||
182 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
183 | ||
2e72b634 KS |
184 | struct mem_cgroup_threshold { |
185 | struct eventfd_ctx *eventfd; | |
186 | u64 threshold; | |
187 | }; | |
188 | ||
9490ff27 | 189 | /* For threshold */ |
2e72b634 KS |
190 | struct mem_cgroup_threshold_ary { |
191 | /* An array index points to threshold just below usage. */ | |
5407a562 | 192 | int current_threshold; |
2e72b634 KS |
193 | /* Size of entries[] */ |
194 | unsigned int size; | |
195 | /* Array of thresholds */ | |
196 | struct mem_cgroup_threshold entries[0]; | |
197 | }; | |
2c488db2 KS |
198 | |
199 | struct mem_cgroup_thresholds { | |
200 | /* Primary thresholds array */ | |
201 | struct mem_cgroup_threshold_ary *primary; | |
202 | /* | |
203 | * Spare threshold array. | |
204 | * This is needed to make mem_cgroup_unregister_event() "never fail". | |
205 | * It must be able to store at least primary->size - 1 entries. | |
206 | */ | |
207 | struct mem_cgroup_threshold_ary *spare; | |
208 | }; | |
209 | ||
9490ff27 KH |
210 | /* for OOM */ |
211 | struct mem_cgroup_eventfd_list { | |
212 | struct list_head list; | |
213 | struct eventfd_ctx *eventfd; | |
214 | }; | |
2e72b634 | 215 | |
c0ff4b85 R |
216 | static void mem_cgroup_threshold(struct mem_cgroup *memcg); |
217 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); | |
2e72b634 | 218 | |
8cdea7c0 BS |
219 | /* |
220 | * The memory controller data structure. The memory controller controls both | |
221 | * page cache and RSS per cgroup. We would eventually like to provide | |
222 | * statistics based on the statistics developed by Rik Van Riel for clock-pro, | |
223 | * to help the administrator determine what knobs to tune. | |
224 | * | |
225 | * TODO: Add a water mark for the memory controller. Reclaim will begin when | |
8a9f3ccd BS |
226 | * we hit the water mark. May be even add a low water mark, such that |
227 | * no reclaim occurs from a cgroup at it's low water mark, this is | |
228 | * a feature that will be implemented much later in the future. | |
8cdea7c0 BS |
229 | */ |
230 | struct mem_cgroup { | |
231 | struct cgroup_subsys_state css; | |
232 | /* | |
233 | * the counter to account for memory usage | |
234 | */ | |
235 | struct res_counter res; | |
8c7c6e34 KH |
236 | /* |
237 | * the counter to account for mem+swap usage. | |
238 | */ | |
239 | struct res_counter memsw; | |
78fb7466 PE |
240 | /* |
241 | * Per cgroup active and inactive list, similar to the | |
242 | * per zone LRU lists. | |
78fb7466 | 243 | */ |
6d12e2d8 | 244 | struct mem_cgroup_lru_info info; |
889976db YH |
245 | int last_scanned_node; |
246 | #if MAX_NUMNODES > 1 | |
247 | nodemask_t scan_nodes; | |
453a9bf3 KH |
248 | atomic_t numainfo_events; |
249 | atomic_t numainfo_updating; | |
889976db | 250 | #endif |
18f59ea7 BS |
251 | /* |
252 | * Should the accounting and control be hierarchical, per subtree? | |
253 | */ | |
254 | bool use_hierarchy; | |
79dfdacc MH |
255 | |
256 | bool oom_lock; | |
257 | atomic_t under_oom; | |
258 | ||
8c7c6e34 | 259 | atomic_t refcnt; |
14797e23 | 260 | |
1f4c025b | 261 | int swappiness; |
3c11ecf4 KH |
262 | /* OOM-Killer disable */ |
263 | int oom_kill_disable; | |
a7885eb8 | 264 | |
22a668d7 KH |
265 | /* set when res.limit == memsw.limit */ |
266 | bool memsw_is_minimum; | |
267 | ||
2e72b634 KS |
268 | /* protect arrays of thresholds */ |
269 | struct mutex thresholds_lock; | |
270 | ||
271 | /* thresholds for memory usage. RCU-protected */ | |
2c488db2 | 272 | struct mem_cgroup_thresholds thresholds; |
907860ed | 273 | |
2e72b634 | 274 | /* thresholds for mem+swap usage. RCU-protected */ |
2c488db2 | 275 | struct mem_cgroup_thresholds memsw_thresholds; |
907860ed | 276 | |
9490ff27 KH |
277 | /* For oom notifier event fd */ |
278 | struct list_head oom_notify; | |
185efc0f | 279 | |
7dc74be0 DN |
280 | /* |
281 | * Should we move charges of a task when a task is moved into this | |
282 | * mem_cgroup ? And what type of charges should we move ? | |
283 | */ | |
284 | unsigned long move_charge_at_immigrate; | |
d52aa412 | 285 | /* |
c62b1a3b | 286 | * percpu counter. |
d52aa412 | 287 | */ |
c62b1a3b | 288 | struct mem_cgroup_stat_cpu *stat; |
711d3d2c KH |
289 | /* |
290 | * used when a cpu is offlined or other synchronizations | |
291 | * See mem_cgroup_read_stat(). | |
292 | */ | |
293 | struct mem_cgroup_stat_cpu nocpu_base; | |
294 | spinlock_t pcp_counter_lock; | |
d1a4c0b3 GC |
295 | |
296 | #ifdef CONFIG_INET | |
297 | struct tcp_memcontrol tcp_mem; | |
298 | #endif | |
8cdea7c0 BS |
299 | }; |
300 | ||
7dc74be0 DN |
301 | /* Stuffs for move charges at task migration. */ |
302 | /* | |
303 | * Types of charges to be moved. "move_charge_at_immitgrate" is treated as a | |
304 | * left-shifted bitmap of these types. | |
305 | */ | |
306 | enum move_type { | |
4ffef5fe | 307 | MOVE_CHARGE_TYPE_ANON, /* private anonymous page and swap of it */ |
87946a72 | 308 | MOVE_CHARGE_TYPE_FILE, /* file page(including tmpfs) and swap of it */ |
7dc74be0 DN |
309 | NR_MOVE_TYPE, |
310 | }; | |
311 | ||
4ffef5fe DN |
312 | /* "mc" and its members are protected by cgroup_mutex */ |
313 | static struct move_charge_struct { | |
b1dd693e | 314 | spinlock_t lock; /* for from, to */ |
4ffef5fe DN |
315 | struct mem_cgroup *from; |
316 | struct mem_cgroup *to; | |
317 | unsigned long precharge; | |
854ffa8d | 318 | unsigned long moved_charge; |
483c30b5 | 319 | unsigned long moved_swap; |
8033b97c DN |
320 | struct task_struct *moving_task; /* a task moving charges */ |
321 | wait_queue_head_t waitq; /* a waitq for other context */ | |
322 | } mc = { | |
2bd9bb20 | 323 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
324 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
325 | }; | |
4ffef5fe | 326 | |
90254a65 DN |
327 | static bool move_anon(void) |
328 | { | |
329 | return test_bit(MOVE_CHARGE_TYPE_ANON, | |
330 | &mc.to->move_charge_at_immigrate); | |
331 | } | |
332 | ||
87946a72 DN |
333 | static bool move_file(void) |
334 | { | |
335 | return test_bit(MOVE_CHARGE_TYPE_FILE, | |
336 | &mc.to->move_charge_at_immigrate); | |
337 | } | |
338 | ||
4e416953 BS |
339 | /* |
340 | * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft | |
341 | * limit reclaim to prevent infinite loops, if they ever occur. | |
342 | */ | |
343 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS (100) | |
344 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS (2) | |
345 | ||
217bc319 KH |
346 | enum charge_type { |
347 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, | |
348 | MEM_CGROUP_CHARGE_TYPE_MAPPED, | |
4f98a2fe | 349 | MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ |
c05555b5 | 350 | MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ |
d13d1443 | 351 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
8a9478ca | 352 | MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ |
c05555b5 KH |
353 | NR_CHARGE_TYPE, |
354 | }; | |
355 | ||
8c7c6e34 | 356 | /* for encoding cft->private value on file */ |
65c64ce8 GC |
357 | #define _MEM (0) |
358 | #define _MEMSWAP (1) | |
359 | #define _OOM_TYPE (2) | |
8c7c6e34 KH |
360 | #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val)) |
361 | #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff) | |
362 | #define MEMFILE_ATTR(val) ((val) & 0xffff) | |
9490ff27 KH |
363 | /* Used for OOM nofiier */ |
364 | #define OOM_CONTROL (0) | |
8c7c6e34 | 365 | |
75822b44 BS |
366 | /* |
367 | * Reclaim flags for mem_cgroup_hierarchical_reclaim | |
368 | */ | |
369 | #define MEM_CGROUP_RECLAIM_NOSWAP_BIT 0x0 | |
370 | #define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT) | |
371 | #define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1 | |
372 | #define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT) | |
4e416953 BS |
373 | #define MEM_CGROUP_RECLAIM_SOFT_BIT 0x2 |
374 | #define MEM_CGROUP_RECLAIM_SOFT (1 << MEM_CGROUP_RECLAIM_SOFT_BIT) | |
75822b44 | 375 | |
c0ff4b85 R |
376 | static void mem_cgroup_get(struct mem_cgroup *memcg); |
377 | static void mem_cgroup_put(struct mem_cgroup *memcg); | |
e1aab161 GC |
378 | |
379 | /* Writing them here to avoid exposing memcg's inner layout */ | |
380 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM | |
381 | #ifdef CONFIG_INET | |
382 | #include <net/sock.h> | |
d1a4c0b3 | 383 | #include <net/ip.h> |
e1aab161 GC |
384 | |
385 | static bool mem_cgroup_is_root(struct mem_cgroup *memcg); | |
386 | void sock_update_memcg(struct sock *sk) | |
387 | { | |
e1aab161 GC |
388 | if (static_branch(&memcg_socket_limit_enabled)) { |
389 | struct mem_cgroup *memcg; | |
390 | ||
391 | BUG_ON(!sk->sk_prot->proto_cgroup); | |
392 | ||
f3f511e1 GC |
393 | /* Socket cloning can throw us here with sk_cgrp already |
394 | * filled. It won't however, necessarily happen from | |
395 | * process context. So the test for root memcg given | |
396 | * the current task's memcg won't help us in this case. | |
397 | * | |
398 | * Respecting the original socket's memcg is a better | |
399 | * decision in this case. | |
400 | */ | |
401 | if (sk->sk_cgrp) { | |
402 | BUG_ON(mem_cgroup_is_root(sk->sk_cgrp->memcg)); | |
403 | mem_cgroup_get(sk->sk_cgrp->memcg); | |
404 | return; | |
405 | } | |
406 | ||
e1aab161 GC |
407 | rcu_read_lock(); |
408 | memcg = mem_cgroup_from_task(current); | |
409 | if (!mem_cgroup_is_root(memcg)) { | |
410 | mem_cgroup_get(memcg); | |
411 | sk->sk_cgrp = sk->sk_prot->proto_cgroup(memcg); | |
412 | } | |
413 | rcu_read_unlock(); | |
414 | } | |
415 | } | |
416 | EXPORT_SYMBOL(sock_update_memcg); | |
417 | ||
418 | void sock_release_memcg(struct sock *sk) | |
419 | { | |
420 | if (static_branch(&memcg_socket_limit_enabled) && sk->sk_cgrp) { | |
421 | struct mem_cgroup *memcg; | |
422 | WARN_ON(!sk->sk_cgrp->memcg); | |
423 | memcg = sk->sk_cgrp->memcg; | |
424 | mem_cgroup_put(memcg); | |
425 | } | |
426 | } | |
d1a4c0b3 GC |
427 | |
428 | struct cg_proto *tcp_proto_cgroup(struct mem_cgroup *memcg) | |
429 | { | |
430 | if (!memcg || mem_cgroup_is_root(memcg)) | |
431 | return NULL; | |
432 | ||
433 | return &memcg->tcp_mem.cg_proto; | |
434 | } | |
435 | EXPORT_SYMBOL(tcp_proto_cgroup); | |
e1aab161 GC |
436 | #endif /* CONFIG_INET */ |
437 | #endif /* CONFIG_CGROUP_MEM_RES_CTLR_KMEM */ | |
438 | ||
c0ff4b85 | 439 | static void drain_all_stock_async(struct mem_cgroup *memcg); |
8c7c6e34 | 440 | |
f64c3f54 | 441 | static struct mem_cgroup_per_zone * |
c0ff4b85 | 442 | mem_cgroup_zoneinfo(struct mem_cgroup *memcg, int nid, int zid) |
f64c3f54 | 443 | { |
c0ff4b85 | 444 | return &memcg->info.nodeinfo[nid]->zoneinfo[zid]; |
f64c3f54 BS |
445 | } |
446 | ||
c0ff4b85 | 447 | struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *memcg) |
d324236b | 448 | { |
c0ff4b85 | 449 | return &memcg->css; |
d324236b WF |
450 | } |
451 | ||
f64c3f54 | 452 | static struct mem_cgroup_per_zone * |
c0ff4b85 | 453 | page_cgroup_zoneinfo(struct mem_cgroup *memcg, struct page *page) |
f64c3f54 | 454 | { |
97a6c37b JW |
455 | int nid = page_to_nid(page); |
456 | int zid = page_zonenum(page); | |
f64c3f54 | 457 | |
c0ff4b85 | 458 | return mem_cgroup_zoneinfo(memcg, nid, zid); |
f64c3f54 BS |
459 | } |
460 | ||
461 | static struct mem_cgroup_tree_per_zone * | |
462 | soft_limit_tree_node_zone(int nid, int zid) | |
463 | { | |
464 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
465 | } | |
466 | ||
467 | static struct mem_cgroup_tree_per_zone * | |
468 | soft_limit_tree_from_page(struct page *page) | |
469 | { | |
470 | int nid = page_to_nid(page); | |
471 | int zid = page_zonenum(page); | |
472 | ||
473 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
474 | } | |
475 | ||
476 | static void | |
c0ff4b85 | 477 | __mem_cgroup_insert_exceeded(struct mem_cgroup *memcg, |
f64c3f54 | 478 | struct mem_cgroup_per_zone *mz, |
ef8745c1 KH |
479 | struct mem_cgroup_tree_per_zone *mctz, |
480 | unsigned long long new_usage_in_excess) | |
f64c3f54 BS |
481 | { |
482 | struct rb_node **p = &mctz->rb_root.rb_node; | |
483 | struct rb_node *parent = NULL; | |
484 | struct mem_cgroup_per_zone *mz_node; | |
485 | ||
486 | if (mz->on_tree) | |
487 | return; | |
488 | ||
ef8745c1 KH |
489 | mz->usage_in_excess = new_usage_in_excess; |
490 | if (!mz->usage_in_excess) | |
491 | return; | |
f64c3f54 BS |
492 | while (*p) { |
493 | parent = *p; | |
494 | mz_node = rb_entry(parent, struct mem_cgroup_per_zone, | |
495 | tree_node); | |
496 | if (mz->usage_in_excess < mz_node->usage_in_excess) | |
497 | p = &(*p)->rb_left; | |
498 | /* | |
499 | * We can't avoid mem cgroups that are over their soft | |
500 | * limit by the same amount | |
501 | */ | |
502 | else if (mz->usage_in_excess >= mz_node->usage_in_excess) | |
503 | p = &(*p)->rb_right; | |
504 | } | |
505 | rb_link_node(&mz->tree_node, parent, p); | |
506 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
507 | mz->on_tree = true; | |
4e416953 BS |
508 | } |
509 | ||
510 | static void | |
c0ff4b85 | 511 | __mem_cgroup_remove_exceeded(struct mem_cgroup *memcg, |
4e416953 BS |
512 | struct mem_cgroup_per_zone *mz, |
513 | struct mem_cgroup_tree_per_zone *mctz) | |
514 | { | |
515 | if (!mz->on_tree) | |
516 | return; | |
517 | rb_erase(&mz->tree_node, &mctz->rb_root); | |
518 | mz->on_tree = false; | |
519 | } | |
520 | ||
f64c3f54 | 521 | static void |
c0ff4b85 | 522 | mem_cgroup_remove_exceeded(struct mem_cgroup *memcg, |
f64c3f54 BS |
523 | struct mem_cgroup_per_zone *mz, |
524 | struct mem_cgroup_tree_per_zone *mctz) | |
525 | { | |
526 | spin_lock(&mctz->lock); | |
c0ff4b85 | 527 | __mem_cgroup_remove_exceeded(memcg, mz, mctz); |
f64c3f54 BS |
528 | spin_unlock(&mctz->lock); |
529 | } | |
530 | ||
f64c3f54 | 531 | |
c0ff4b85 | 532 | static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page) |
f64c3f54 | 533 | { |
ef8745c1 | 534 | unsigned long long excess; |
f64c3f54 BS |
535 | struct mem_cgroup_per_zone *mz; |
536 | struct mem_cgroup_tree_per_zone *mctz; | |
4e649152 KH |
537 | int nid = page_to_nid(page); |
538 | int zid = page_zonenum(page); | |
f64c3f54 BS |
539 | mctz = soft_limit_tree_from_page(page); |
540 | ||
541 | /* | |
4e649152 KH |
542 | * Necessary to update all ancestors when hierarchy is used. |
543 | * because their event counter is not touched. | |
f64c3f54 | 544 | */ |
c0ff4b85 R |
545 | for (; memcg; memcg = parent_mem_cgroup(memcg)) { |
546 | mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
547 | excess = res_counter_soft_limit_excess(&memcg->res); | |
4e649152 KH |
548 | /* |
549 | * We have to update the tree if mz is on RB-tree or | |
550 | * mem is over its softlimit. | |
551 | */ | |
ef8745c1 | 552 | if (excess || mz->on_tree) { |
4e649152 KH |
553 | spin_lock(&mctz->lock); |
554 | /* if on-tree, remove it */ | |
555 | if (mz->on_tree) | |
c0ff4b85 | 556 | __mem_cgroup_remove_exceeded(memcg, mz, mctz); |
4e649152 | 557 | /* |
ef8745c1 KH |
558 | * Insert again. mz->usage_in_excess will be updated. |
559 | * If excess is 0, no tree ops. | |
4e649152 | 560 | */ |
c0ff4b85 | 561 | __mem_cgroup_insert_exceeded(memcg, mz, mctz, excess); |
4e649152 KH |
562 | spin_unlock(&mctz->lock); |
563 | } | |
f64c3f54 BS |
564 | } |
565 | } | |
566 | ||
c0ff4b85 | 567 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) |
f64c3f54 BS |
568 | { |
569 | int node, zone; | |
570 | struct mem_cgroup_per_zone *mz; | |
571 | struct mem_cgroup_tree_per_zone *mctz; | |
572 | ||
573 | for_each_node_state(node, N_POSSIBLE) { | |
574 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
c0ff4b85 | 575 | mz = mem_cgroup_zoneinfo(memcg, node, zone); |
f64c3f54 | 576 | mctz = soft_limit_tree_node_zone(node, zone); |
c0ff4b85 | 577 | mem_cgroup_remove_exceeded(memcg, mz, mctz); |
f64c3f54 BS |
578 | } |
579 | } | |
580 | } | |
581 | ||
4e416953 BS |
582 | static struct mem_cgroup_per_zone * |
583 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
584 | { | |
585 | struct rb_node *rightmost = NULL; | |
26251eaf | 586 | struct mem_cgroup_per_zone *mz; |
4e416953 BS |
587 | |
588 | retry: | |
26251eaf | 589 | mz = NULL; |
4e416953 BS |
590 | rightmost = rb_last(&mctz->rb_root); |
591 | if (!rightmost) | |
592 | goto done; /* Nothing to reclaim from */ | |
593 | ||
594 | mz = rb_entry(rightmost, struct mem_cgroup_per_zone, tree_node); | |
595 | /* | |
596 | * Remove the node now but someone else can add it back, | |
597 | * we will to add it back at the end of reclaim to its correct | |
598 | * position in the tree. | |
599 | */ | |
600 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); | |
601 | if (!res_counter_soft_limit_excess(&mz->mem->res) || | |
602 | !css_tryget(&mz->mem->css)) | |
603 | goto retry; | |
604 | done: | |
605 | return mz; | |
606 | } | |
607 | ||
608 | static struct mem_cgroup_per_zone * | |
609 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
610 | { | |
611 | struct mem_cgroup_per_zone *mz; | |
612 | ||
613 | spin_lock(&mctz->lock); | |
614 | mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
615 | spin_unlock(&mctz->lock); | |
616 | return mz; | |
617 | } | |
618 | ||
711d3d2c KH |
619 | /* |
620 | * Implementation Note: reading percpu statistics for memcg. | |
621 | * | |
622 | * Both of vmstat[] and percpu_counter has threshold and do periodic | |
623 | * synchronization to implement "quick" read. There are trade-off between | |
624 | * reading cost and precision of value. Then, we may have a chance to implement | |
625 | * a periodic synchronizion of counter in memcg's counter. | |
626 | * | |
627 | * But this _read() function is used for user interface now. The user accounts | |
628 | * memory usage by memory cgroup and he _always_ requires exact value because | |
629 | * he accounts memory. Even if we provide quick-and-fuzzy read, we always | |
630 | * have to visit all online cpus and make sum. So, for now, unnecessary | |
631 | * synchronization is not implemented. (just implemented for cpu hotplug) | |
632 | * | |
633 | * If there are kernel internal actions which can make use of some not-exact | |
634 | * value, and reading all cpu value can be performance bottleneck in some | |
635 | * common workload, threashold and synchonization as vmstat[] should be | |
636 | * implemented. | |
637 | */ | |
c0ff4b85 | 638 | static long mem_cgroup_read_stat(struct mem_cgroup *memcg, |
7a159cc9 | 639 | enum mem_cgroup_stat_index idx) |
c62b1a3b | 640 | { |
7a159cc9 | 641 | long val = 0; |
c62b1a3b | 642 | int cpu; |
c62b1a3b | 643 | |
711d3d2c KH |
644 | get_online_cpus(); |
645 | for_each_online_cpu(cpu) | |
c0ff4b85 | 646 | val += per_cpu(memcg->stat->count[idx], cpu); |
711d3d2c | 647 | #ifdef CONFIG_HOTPLUG_CPU |
c0ff4b85 R |
648 | spin_lock(&memcg->pcp_counter_lock); |
649 | val += memcg->nocpu_base.count[idx]; | |
650 | spin_unlock(&memcg->pcp_counter_lock); | |
711d3d2c KH |
651 | #endif |
652 | put_online_cpus(); | |
c62b1a3b KH |
653 | return val; |
654 | } | |
655 | ||
c0ff4b85 | 656 | static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg, |
0c3e73e8 BS |
657 | bool charge) |
658 | { | |
659 | int val = (charge) ? 1 : -1; | |
c0ff4b85 | 660 | this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_SWAPOUT], val); |
0c3e73e8 BS |
661 | } |
662 | ||
c0ff4b85 | 663 | void mem_cgroup_pgfault(struct mem_cgroup *memcg, int val) |
456f998e | 664 | { |
c0ff4b85 | 665 | this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT], val); |
456f998e YH |
666 | } |
667 | ||
c0ff4b85 | 668 | void mem_cgroup_pgmajfault(struct mem_cgroup *memcg, int val) |
456f998e | 669 | { |
c0ff4b85 | 670 | this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT], val); |
456f998e YH |
671 | } |
672 | ||
c0ff4b85 | 673 | static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg, |
e9f8974f JW |
674 | enum mem_cgroup_events_index idx) |
675 | { | |
676 | unsigned long val = 0; | |
677 | int cpu; | |
678 | ||
679 | for_each_online_cpu(cpu) | |
c0ff4b85 | 680 | val += per_cpu(memcg->stat->events[idx], cpu); |
e9f8974f | 681 | #ifdef CONFIG_HOTPLUG_CPU |
c0ff4b85 R |
682 | spin_lock(&memcg->pcp_counter_lock); |
683 | val += memcg->nocpu_base.events[idx]; | |
684 | spin_unlock(&memcg->pcp_counter_lock); | |
e9f8974f JW |
685 | #endif |
686 | return val; | |
687 | } | |
688 | ||
c0ff4b85 | 689 | static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, |
e401f176 | 690 | bool file, int nr_pages) |
d52aa412 | 691 | { |
c62b1a3b KH |
692 | preempt_disable(); |
693 | ||
e401f176 | 694 | if (file) |
c0ff4b85 R |
695 | __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_CACHE], |
696 | nr_pages); | |
d52aa412 | 697 | else |
c0ff4b85 R |
698 | __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_RSS], |
699 | nr_pages); | |
55e462b0 | 700 | |
e401f176 KH |
701 | /* pagein of a big page is an event. So, ignore page size */ |
702 | if (nr_pages > 0) | |
c0ff4b85 | 703 | __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGIN]); |
3751d604 | 704 | else { |
c0ff4b85 | 705 | __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT]); |
3751d604 KH |
706 | nr_pages = -nr_pages; /* for event */ |
707 | } | |
e401f176 | 708 | |
c0ff4b85 | 709 | __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_COUNT], nr_pages); |
2e72b634 | 710 | |
c62b1a3b | 711 | preempt_enable(); |
6d12e2d8 KH |
712 | } |
713 | ||
bb2a0de9 | 714 | unsigned long |
c0ff4b85 | 715 | mem_cgroup_zone_nr_lru_pages(struct mem_cgroup *memcg, int nid, int zid, |
bb2a0de9 | 716 | unsigned int lru_mask) |
889976db YH |
717 | { |
718 | struct mem_cgroup_per_zone *mz; | |
bb2a0de9 KH |
719 | enum lru_list l; |
720 | unsigned long ret = 0; | |
721 | ||
c0ff4b85 | 722 | mz = mem_cgroup_zoneinfo(memcg, nid, zid); |
bb2a0de9 KH |
723 | |
724 | for_each_lru(l) { | |
725 | if (BIT(l) & lru_mask) | |
726 | ret += MEM_CGROUP_ZSTAT(mz, l); | |
727 | } | |
728 | return ret; | |
729 | } | |
730 | ||
731 | static unsigned long | |
c0ff4b85 | 732 | mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, |
bb2a0de9 KH |
733 | int nid, unsigned int lru_mask) |
734 | { | |
889976db YH |
735 | u64 total = 0; |
736 | int zid; | |
737 | ||
bb2a0de9 | 738 | for (zid = 0; zid < MAX_NR_ZONES; zid++) |
c0ff4b85 R |
739 | total += mem_cgroup_zone_nr_lru_pages(memcg, |
740 | nid, zid, lru_mask); | |
bb2a0de9 | 741 | |
889976db YH |
742 | return total; |
743 | } | |
bb2a0de9 | 744 | |
c0ff4b85 | 745 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, |
bb2a0de9 | 746 | unsigned int lru_mask) |
6d12e2d8 | 747 | { |
889976db | 748 | int nid; |
6d12e2d8 KH |
749 | u64 total = 0; |
750 | ||
bb2a0de9 | 751 | for_each_node_state(nid, N_HIGH_MEMORY) |
c0ff4b85 | 752 | total += mem_cgroup_node_nr_lru_pages(memcg, nid, lru_mask); |
6d12e2d8 | 753 | return total; |
d52aa412 KH |
754 | } |
755 | ||
c0ff4b85 | 756 | static bool __memcg_event_check(struct mem_cgroup *memcg, int target) |
7a159cc9 JW |
757 | { |
758 | unsigned long val, next; | |
759 | ||
4799401f SR |
760 | val = __this_cpu_read(memcg->stat->events[MEM_CGROUP_EVENTS_COUNT]); |
761 | next = __this_cpu_read(memcg->stat->targets[target]); | |
7a159cc9 JW |
762 | /* from time_after() in jiffies.h */ |
763 | return ((long)next - (long)val < 0); | |
764 | } | |
765 | ||
c0ff4b85 | 766 | static void __mem_cgroup_target_update(struct mem_cgroup *memcg, int target) |
d2265e6f | 767 | { |
7a159cc9 | 768 | unsigned long val, next; |
d2265e6f | 769 | |
4799401f | 770 | val = __this_cpu_read(memcg->stat->events[MEM_CGROUP_EVENTS_COUNT]); |
d2265e6f | 771 | |
7a159cc9 JW |
772 | switch (target) { |
773 | case MEM_CGROUP_TARGET_THRESH: | |
774 | next = val + THRESHOLDS_EVENTS_TARGET; | |
775 | break; | |
776 | case MEM_CGROUP_TARGET_SOFTLIMIT: | |
777 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
778 | break; | |
453a9bf3 KH |
779 | case MEM_CGROUP_TARGET_NUMAINFO: |
780 | next = val + NUMAINFO_EVENTS_TARGET; | |
781 | break; | |
7a159cc9 JW |
782 | default: |
783 | return; | |
784 | } | |
785 | ||
4799401f | 786 | __this_cpu_write(memcg->stat->targets[target], next); |
d2265e6f KH |
787 | } |
788 | ||
789 | /* | |
790 | * Check events in order. | |
791 | * | |
792 | */ | |
c0ff4b85 | 793 | static void memcg_check_events(struct mem_cgroup *memcg, struct page *page) |
d2265e6f | 794 | { |
4799401f | 795 | preempt_disable(); |
d2265e6f | 796 | /* threshold event is triggered in finer grain than soft limit */ |
c0ff4b85 R |
797 | if (unlikely(__memcg_event_check(memcg, MEM_CGROUP_TARGET_THRESH))) { |
798 | mem_cgroup_threshold(memcg); | |
799 | __mem_cgroup_target_update(memcg, MEM_CGROUP_TARGET_THRESH); | |
800 | if (unlikely(__memcg_event_check(memcg, | |
453a9bf3 | 801 | MEM_CGROUP_TARGET_SOFTLIMIT))) { |
c0ff4b85 R |
802 | mem_cgroup_update_tree(memcg, page); |
803 | __mem_cgroup_target_update(memcg, | |
453a9bf3 KH |
804 | MEM_CGROUP_TARGET_SOFTLIMIT); |
805 | } | |
806 | #if MAX_NUMNODES > 1 | |
c0ff4b85 | 807 | if (unlikely(__memcg_event_check(memcg, |
453a9bf3 | 808 | MEM_CGROUP_TARGET_NUMAINFO))) { |
c0ff4b85 R |
809 | atomic_inc(&memcg->numainfo_events); |
810 | __mem_cgroup_target_update(memcg, | |
453a9bf3 | 811 | MEM_CGROUP_TARGET_NUMAINFO); |
7a159cc9 | 812 | } |
453a9bf3 | 813 | #endif |
d2265e6f | 814 | } |
4799401f | 815 | preempt_enable(); |
d2265e6f KH |
816 | } |
817 | ||
d1a4c0b3 | 818 | struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) |
8cdea7c0 BS |
819 | { |
820 | return container_of(cgroup_subsys_state(cont, | |
821 | mem_cgroup_subsys_id), struct mem_cgroup, | |
822 | css); | |
823 | } | |
824 | ||
cf475ad2 | 825 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 826 | { |
31a78f23 BS |
827 | /* |
828 | * mm_update_next_owner() may clear mm->owner to NULL | |
829 | * if it races with swapoff, page migration, etc. | |
830 | * So this can be called with p == NULL. | |
831 | */ | |
832 | if (unlikely(!p)) | |
833 | return NULL; | |
834 | ||
78fb7466 PE |
835 | return container_of(task_subsys_state(p, mem_cgroup_subsys_id), |
836 | struct mem_cgroup, css); | |
837 | } | |
838 | ||
a433658c | 839 | struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) |
54595fe2 | 840 | { |
c0ff4b85 | 841 | struct mem_cgroup *memcg = NULL; |
0b7f569e KH |
842 | |
843 | if (!mm) | |
844 | return NULL; | |
54595fe2 KH |
845 | /* |
846 | * Because we have no locks, mm->owner's may be being moved to other | |
847 | * cgroup. We use css_tryget() here even if this looks | |
848 | * pessimistic (rather than adding locks here). | |
849 | */ | |
850 | rcu_read_lock(); | |
851 | do { | |
c0ff4b85 R |
852 | memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); |
853 | if (unlikely(!memcg)) | |
54595fe2 | 854 | break; |
c0ff4b85 | 855 | } while (!css_tryget(&memcg->css)); |
54595fe2 | 856 | rcu_read_unlock(); |
c0ff4b85 | 857 | return memcg; |
54595fe2 KH |
858 | } |
859 | ||
527a5ec9 JW |
860 | struct mem_cgroup_reclaim_cookie { |
861 | struct zone *zone; | |
862 | int priority; | |
863 | unsigned int generation; | |
864 | }; | |
865 | ||
866 | static struct mem_cgroup * | |
867 | mem_cgroup_iter(struct mem_cgroup *root, | |
868 | struct mem_cgroup *prev, | |
869 | struct mem_cgroup_reclaim_cookie *reclaim) | |
14067bb3 | 870 | { |
9f3a0d09 JW |
871 | struct mem_cgroup *memcg = NULL; |
872 | int id = 0; | |
711d3d2c | 873 | |
9f3a0d09 JW |
874 | if (!root) |
875 | root = root_mem_cgroup; | |
7d74b06f | 876 | |
9f3a0d09 JW |
877 | if (prev && !reclaim) |
878 | id = css_id(&prev->css); | |
14067bb3 | 879 | |
9f3a0d09 JW |
880 | if (prev && prev != root) |
881 | css_put(&prev->css); | |
14067bb3 | 882 | |
9f3a0d09 JW |
883 | if (!root->use_hierarchy && root != root_mem_cgroup) { |
884 | if (prev) | |
885 | return NULL; | |
886 | return root; | |
887 | } | |
14067bb3 | 888 | |
9f3a0d09 | 889 | while (!memcg) { |
527a5ec9 | 890 | struct mem_cgroup_reclaim_iter *uninitialized_var(iter); |
9f3a0d09 | 891 | struct cgroup_subsys_state *css; |
711d3d2c | 892 | |
527a5ec9 JW |
893 | if (reclaim) { |
894 | int nid = zone_to_nid(reclaim->zone); | |
895 | int zid = zone_idx(reclaim->zone); | |
896 | struct mem_cgroup_per_zone *mz; | |
897 | ||
898 | mz = mem_cgroup_zoneinfo(root, nid, zid); | |
899 | iter = &mz->reclaim_iter[reclaim->priority]; | |
900 | if (prev && reclaim->generation != iter->generation) | |
901 | return NULL; | |
902 | id = iter->position; | |
903 | } | |
7d74b06f | 904 | |
9f3a0d09 JW |
905 | rcu_read_lock(); |
906 | css = css_get_next(&mem_cgroup_subsys, id + 1, &root->css, &id); | |
907 | if (css) { | |
908 | if (css == &root->css || css_tryget(css)) | |
909 | memcg = container_of(css, | |
910 | struct mem_cgroup, css); | |
911 | } else | |
912 | id = 0; | |
14067bb3 | 913 | rcu_read_unlock(); |
14067bb3 | 914 | |
527a5ec9 JW |
915 | if (reclaim) { |
916 | iter->position = id; | |
917 | if (!css) | |
918 | iter->generation++; | |
919 | else if (!prev && memcg) | |
920 | reclaim->generation = iter->generation; | |
921 | } | |
9f3a0d09 JW |
922 | |
923 | if (prev && !css) | |
924 | return NULL; | |
925 | } | |
926 | return memcg; | |
14067bb3 | 927 | } |
7d74b06f | 928 | |
9f3a0d09 JW |
929 | static void mem_cgroup_iter_break(struct mem_cgroup *root, |
930 | struct mem_cgroup *prev) | |
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) { | |
971 | case PGMAJFAULT: | |
c0ff4b85 | 972 | mem_cgroup_pgmajfault(memcg, 1); |
456f998e YH |
973 | break; |
974 | case PGFAULT: | |
c0ff4b85 | 975 | mem_cgroup_pgfault(memcg, 1); |
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 | ||
08e552c6 KH |
985 | /* |
986 | * Following LRU functions are allowed to be used without PCG_LOCK. | |
987 | * Operations are called by routine of global LRU independently from memcg. | |
988 | * What we have to take care of here is validness of pc->mem_cgroup. | |
989 | * | |
990 | * Changes to pc->mem_cgroup happens when | |
991 | * 1. charge | |
992 | * 2. moving account | |
993 | * In typical case, "charge" is done before add-to-lru. Exception is SwapCache. | |
994 | * It is added to LRU before charge. | |
995 | * If PCG_USED bit is not set, page_cgroup is not added to this private LRU. | |
996 | * When moving account, the page is not on LRU. It's isolated. | |
997 | */ | |
4f98a2fe | 998 | |
08e552c6 KH |
999 | void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru) |
1000 | { | |
1001 | struct page_cgroup *pc; | |
08e552c6 | 1002 | struct mem_cgroup_per_zone *mz; |
6d12e2d8 | 1003 | |
f8d66542 | 1004 | if (mem_cgroup_disabled()) |
08e552c6 KH |
1005 | return; |
1006 | pc = lookup_page_cgroup(page); | |
1007 | /* can happen while we handle swapcache. */ | |
4b3bde4c | 1008 | if (!TestClearPageCgroupAcctLRU(pc)) |
08e552c6 | 1009 | return; |
4b3bde4c | 1010 | VM_BUG_ON(!pc->mem_cgroup); |
544122e5 KH |
1011 | /* |
1012 | * We don't check PCG_USED bit. It's cleared when the "page" is finally | |
1013 | * removed from global LRU. | |
1014 | */ | |
97a6c37b | 1015 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
ece35ca8 KH |
1016 | /* huge page split is done under lru_lock. so, we have no races. */ |
1017 | MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page); | |
4b3bde4c BS |
1018 | if (mem_cgroup_is_root(pc->mem_cgroup)) |
1019 | return; | |
1020 | VM_BUG_ON(list_empty(&pc->lru)); | |
08e552c6 | 1021 | list_del_init(&pc->lru); |
6d12e2d8 KH |
1022 | } |
1023 | ||
08e552c6 | 1024 | void mem_cgroup_del_lru(struct page *page) |
6d12e2d8 | 1025 | { |
08e552c6 KH |
1026 | mem_cgroup_del_lru_list(page, page_lru(page)); |
1027 | } | |
b69408e8 | 1028 | |
3f58a829 MK |
1029 | /* |
1030 | * Writeback is about to end against a page which has been marked for immediate | |
1031 | * reclaim. If it still appears to be reclaimable, move it to the tail of the | |
1032 | * inactive list. | |
1033 | */ | |
1034 | void mem_cgroup_rotate_reclaimable_page(struct page *page) | |
1035 | { | |
1036 | struct mem_cgroup_per_zone *mz; | |
1037 | struct page_cgroup *pc; | |
1038 | enum lru_list lru = page_lru(page); | |
1039 | ||
1040 | if (mem_cgroup_disabled()) | |
1041 | return; | |
1042 | ||
1043 | pc = lookup_page_cgroup(page); | |
1044 | /* unused or root page is not rotated. */ | |
1045 | if (!PageCgroupUsed(pc)) | |
1046 | return; | |
1047 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ | |
1048 | smp_rmb(); | |
1049 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
1050 | return; | |
97a6c37b | 1051 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
3f58a829 MK |
1052 | list_move_tail(&pc->lru, &mz->lists[lru]); |
1053 | } | |
1054 | ||
08e552c6 KH |
1055 | void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru) |
1056 | { | |
1057 | struct mem_cgroup_per_zone *mz; | |
1058 | struct page_cgroup *pc; | |
b69408e8 | 1059 | |
f8d66542 | 1060 | if (mem_cgroup_disabled()) |
08e552c6 | 1061 | return; |
6d12e2d8 | 1062 | |
08e552c6 | 1063 | pc = lookup_page_cgroup(page); |
4b3bde4c | 1064 | /* unused or root page is not rotated. */ |
713735b4 JW |
1065 | if (!PageCgroupUsed(pc)) |
1066 | return; | |
1067 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ | |
1068 | smp_rmb(); | |
1069 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
08e552c6 | 1070 | return; |
97a6c37b | 1071 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
08e552c6 | 1072 | list_move(&pc->lru, &mz->lists[lru]); |
6d12e2d8 KH |
1073 | } |
1074 | ||
08e552c6 | 1075 | void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru) |
66e1707b | 1076 | { |
08e552c6 KH |
1077 | struct page_cgroup *pc; |
1078 | struct mem_cgroup_per_zone *mz; | |
6d12e2d8 | 1079 | |
f8d66542 | 1080 | if (mem_cgroup_disabled()) |
08e552c6 KH |
1081 | return; |
1082 | pc = lookup_page_cgroup(page); | |
4b3bde4c | 1083 | VM_BUG_ON(PageCgroupAcctLRU(pc)); |
a61ed3ce JW |
1084 | /* |
1085 | * putback: charge: | |
1086 | * SetPageLRU SetPageCgroupUsed | |
1087 | * smp_mb smp_mb | |
1088 | * PageCgroupUsed && add to memcg LRU PageLRU && add to memcg LRU | |
1089 | * | |
1090 | * Ensure that one of the two sides adds the page to the memcg | |
1091 | * LRU during a race. | |
1092 | */ | |
1093 | smp_mb(); | |
08e552c6 | 1094 | if (!PageCgroupUsed(pc)) |
894bc310 | 1095 | return; |
713735b4 JW |
1096 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
1097 | smp_rmb(); | |
97a6c37b | 1098 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
ece35ca8 KH |
1099 | /* huge page split is done under lru_lock. so, we have no races. */ |
1100 | MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page); | |
4b3bde4c BS |
1101 | SetPageCgroupAcctLRU(pc); |
1102 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
1103 | return; | |
08e552c6 KH |
1104 | list_add(&pc->lru, &mz->lists[lru]); |
1105 | } | |
544122e5 | 1106 | |
08e552c6 | 1107 | /* |
5a6475a4 KH |
1108 | * At handling SwapCache and other FUSE stuff, pc->mem_cgroup may be changed |
1109 | * while it's linked to lru because the page may be reused after it's fully | |
1110 | * uncharged. To handle that, unlink page_cgroup from LRU when charge it again. | |
1111 | * It's done under lock_page and expected that zone->lru_lock isnever held. | |
08e552c6 | 1112 | */ |
5a6475a4 | 1113 | static void mem_cgroup_lru_del_before_commit(struct page *page) |
08e552c6 | 1114 | { |
544122e5 KH |
1115 | unsigned long flags; |
1116 | struct zone *zone = page_zone(page); | |
1117 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
1118 | ||
5a6475a4 KH |
1119 | /* |
1120 | * Doing this check without taking ->lru_lock seems wrong but this | |
1121 | * is safe. Because if page_cgroup's USED bit is unset, the page | |
1122 | * will not be added to any memcg's LRU. If page_cgroup's USED bit is | |
1123 | * set, the commit after this will fail, anyway. | |
1124 | * This all charge/uncharge is done under some mutual execustion. | |
1125 | * So, we don't need to taking care of changes in USED bit. | |
1126 | */ | |
1127 | if (likely(!PageLRU(page))) | |
1128 | return; | |
1129 | ||
544122e5 KH |
1130 | spin_lock_irqsave(&zone->lru_lock, flags); |
1131 | /* | |
1132 | * Forget old LRU when this page_cgroup is *not* used. This Used bit | |
1133 | * is guarded by lock_page() because the page is SwapCache. | |
1134 | */ | |
1135 | if (!PageCgroupUsed(pc)) | |
1136 | mem_cgroup_del_lru_list(page, page_lru(page)); | |
1137 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
08e552c6 KH |
1138 | } |
1139 | ||
5a6475a4 | 1140 | static void mem_cgroup_lru_add_after_commit(struct page *page) |
544122e5 KH |
1141 | { |
1142 | unsigned long flags; | |
1143 | struct zone *zone = page_zone(page); | |
1144 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
a61ed3ce JW |
1145 | /* |
1146 | * putback: charge: | |
1147 | * SetPageLRU SetPageCgroupUsed | |
1148 | * smp_mb smp_mb | |
1149 | * PageCgroupUsed && add to memcg LRU PageLRU && add to memcg LRU | |
1150 | * | |
1151 | * Ensure that one of the two sides adds the page to the memcg | |
1152 | * LRU during a race. | |
1153 | */ | |
1154 | smp_mb(); | |
5a6475a4 KH |
1155 | /* taking care of that the page is added to LRU while we commit it */ |
1156 | if (likely(!PageLRU(page))) | |
1157 | return; | |
544122e5 KH |
1158 | spin_lock_irqsave(&zone->lru_lock, flags); |
1159 | /* link when the page is linked to LRU but page_cgroup isn't */ | |
4b3bde4c | 1160 | if (PageLRU(page) && !PageCgroupAcctLRU(pc)) |
544122e5 KH |
1161 | mem_cgroup_add_lru_list(page, page_lru(page)); |
1162 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
1163 | } | |
1164 | ||
1165 | ||
08e552c6 KH |
1166 | void mem_cgroup_move_lists(struct page *page, |
1167 | enum lru_list from, enum lru_list to) | |
1168 | { | |
f8d66542 | 1169 | if (mem_cgroup_disabled()) |
08e552c6 KH |
1170 | return; |
1171 | mem_cgroup_del_lru_list(page, from); | |
1172 | mem_cgroup_add_lru_list(page, to); | |
66e1707b BS |
1173 | } |
1174 | ||
3e92041d | 1175 | /* |
c0ff4b85 | 1176 | * Checks whether given mem is same or in the root_mem_cgroup's |
3e92041d MH |
1177 | * hierarchy subtree |
1178 | */ | |
c0ff4b85 R |
1179 | static bool mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg, |
1180 | struct mem_cgroup *memcg) | |
3e92041d | 1181 | { |
c0ff4b85 R |
1182 | if (root_memcg != memcg) { |
1183 | return (root_memcg->use_hierarchy && | |
1184 | css_is_ancestor(&memcg->css, &root_memcg->css)); | |
3e92041d MH |
1185 | } |
1186 | ||
1187 | return true; | |
1188 | } | |
1189 | ||
c0ff4b85 | 1190 | int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *memcg) |
4c4a2214 DR |
1191 | { |
1192 | int ret; | |
0b7f569e | 1193 | struct mem_cgroup *curr = NULL; |
158e0a2d | 1194 | struct task_struct *p; |
4c4a2214 | 1195 | |
158e0a2d KH |
1196 | p = find_lock_task_mm(task); |
1197 | if (!p) | |
1198 | return 0; | |
1199 | curr = try_get_mem_cgroup_from_mm(p->mm); | |
1200 | task_unlock(p); | |
0b7f569e KH |
1201 | if (!curr) |
1202 | return 0; | |
d31f56db | 1203 | /* |
c0ff4b85 | 1204 | * We should check use_hierarchy of "memcg" not "curr". Because checking |
d31f56db | 1205 | * use_hierarchy of "curr" here make this function true if hierarchy is |
c0ff4b85 R |
1206 | * enabled in "curr" and "curr" is a child of "memcg" in *cgroup* |
1207 | * hierarchy(even if use_hierarchy is disabled in "memcg"). | |
d31f56db | 1208 | */ |
c0ff4b85 | 1209 | ret = mem_cgroup_same_or_subtree(memcg, curr); |
0b7f569e | 1210 | css_put(&curr->css); |
4c4a2214 DR |
1211 | return ret; |
1212 | } | |
1213 | ||
9b272977 | 1214 | int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg, struct zone *zone) |
14797e23 | 1215 | { |
9b272977 JW |
1216 | unsigned long inactive_ratio; |
1217 | int nid = zone_to_nid(zone); | |
1218 | int zid = zone_idx(zone); | |
14797e23 | 1219 | unsigned long inactive; |
9b272977 | 1220 | unsigned long active; |
c772be93 | 1221 | unsigned long gb; |
14797e23 | 1222 | |
9b272977 JW |
1223 | inactive = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, |
1224 | BIT(LRU_INACTIVE_ANON)); | |
1225 | active = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, | |
1226 | BIT(LRU_ACTIVE_ANON)); | |
14797e23 | 1227 | |
c772be93 KM |
1228 | gb = (inactive + active) >> (30 - PAGE_SHIFT); |
1229 | if (gb) | |
1230 | inactive_ratio = int_sqrt(10 * gb); | |
1231 | else | |
1232 | inactive_ratio = 1; | |
1233 | ||
9b272977 | 1234 | return inactive * inactive_ratio < active; |
14797e23 KM |
1235 | } |
1236 | ||
9b272977 | 1237 | int mem_cgroup_inactive_file_is_low(struct mem_cgroup *memcg, struct zone *zone) |
56e49d21 RR |
1238 | { |
1239 | unsigned long active; | |
1240 | unsigned long inactive; | |
9b272977 JW |
1241 | int zid = zone_idx(zone); |
1242 | int nid = zone_to_nid(zone); | |
56e49d21 | 1243 | |
9b272977 JW |
1244 | inactive = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, |
1245 | BIT(LRU_INACTIVE_FILE)); | |
1246 | active = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, | |
1247 | BIT(LRU_ACTIVE_FILE)); | |
56e49d21 RR |
1248 | |
1249 | return (active > inactive); | |
1250 | } | |
1251 | ||
3e2f41f1 KM |
1252 | struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg, |
1253 | struct zone *zone) | |
1254 | { | |
13d7e3a2 | 1255 | int nid = zone_to_nid(zone); |
3e2f41f1 KM |
1256 | int zid = zone_idx(zone); |
1257 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
1258 | ||
1259 | return &mz->reclaim_stat; | |
1260 | } | |
1261 | ||
1262 | struct zone_reclaim_stat * | |
1263 | mem_cgroup_get_reclaim_stat_from_page(struct page *page) | |
1264 | { | |
1265 | struct page_cgroup *pc; | |
1266 | struct mem_cgroup_per_zone *mz; | |
1267 | ||
1268 | if (mem_cgroup_disabled()) | |
1269 | return NULL; | |
1270 | ||
1271 | pc = lookup_page_cgroup(page); | |
bd112db8 DN |
1272 | if (!PageCgroupUsed(pc)) |
1273 | return NULL; | |
713735b4 JW |
1274 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
1275 | smp_rmb(); | |
97a6c37b | 1276 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
3e2f41f1 KM |
1277 | return &mz->reclaim_stat; |
1278 | } | |
1279 | ||
66e1707b BS |
1280 | unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, |
1281 | struct list_head *dst, | |
1282 | unsigned long *scanned, int order, | |
4356f21d MK |
1283 | isolate_mode_t mode, |
1284 | struct zone *z, | |
66e1707b | 1285 | struct mem_cgroup *mem_cont, |
4f98a2fe | 1286 | int active, int file) |
66e1707b BS |
1287 | { |
1288 | unsigned long nr_taken = 0; | |
1289 | struct page *page; | |
1290 | unsigned long scan; | |
1291 | LIST_HEAD(pc_list); | |
1292 | struct list_head *src; | |
ff7283fa | 1293 | struct page_cgroup *pc, *tmp; |
13d7e3a2 | 1294 | int nid = zone_to_nid(z); |
1ecaab2b KH |
1295 | int zid = zone_idx(z); |
1296 | struct mem_cgroup_per_zone *mz; | |
b7c46d15 | 1297 | int lru = LRU_FILE * file + active; |
2ffebca6 | 1298 | int ret; |
66e1707b | 1299 | |
cf475ad2 | 1300 | BUG_ON(!mem_cont); |
1ecaab2b | 1301 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); |
b69408e8 | 1302 | src = &mz->lists[lru]; |
66e1707b | 1303 | |
ff7283fa KH |
1304 | scan = 0; |
1305 | list_for_each_entry_safe_reverse(pc, tmp, src, lru) { | |
436c6541 | 1306 | if (scan >= nr_to_scan) |
ff7283fa | 1307 | break; |
08e552c6 | 1308 | |
52d4b9ac KH |
1309 | if (unlikely(!PageCgroupUsed(pc))) |
1310 | continue; | |
5564e88b | 1311 | |
6b3ae58e | 1312 | page = lookup_cgroup_page(pc); |
5564e88b | 1313 | |
436c6541 | 1314 | if (unlikely(!PageLRU(page))) |
ff7283fa | 1315 | continue; |
ff7283fa | 1316 | |
436c6541 | 1317 | scan++; |
2ffebca6 KH |
1318 | ret = __isolate_lru_page(page, mode, file); |
1319 | switch (ret) { | |
1320 | case 0: | |
66e1707b | 1321 | list_move(&page->lru, dst); |
2ffebca6 | 1322 | mem_cgroup_del_lru(page); |
2c888cfb | 1323 | nr_taken += hpage_nr_pages(page); |
2ffebca6 KH |
1324 | break; |
1325 | case -EBUSY: | |
1326 | /* we don't affect global LRU but rotate in our LRU */ | |
1327 | mem_cgroup_rotate_lru_list(page, page_lru(page)); | |
1328 | break; | |
1329 | default: | |
1330 | break; | |
66e1707b BS |
1331 | } |
1332 | } | |
1333 | ||
66e1707b | 1334 | *scanned = scan; |
cc8e970c KM |
1335 | |
1336 | trace_mm_vmscan_memcg_isolate(0, nr_to_scan, scan, nr_taken, | |
1337 | 0, 0, 0, mode); | |
1338 | ||
66e1707b BS |
1339 | return nr_taken; |
1340 | } | |
1341 | ||
6d61ef40 BS |
1342 | #define mem_cgroup_from_res_counter(counter, member) \ |
1343 | container_of(counter, struct mem_cgroup, member) | |
1344 | ||
19942822 | 1345 | /** |
9d11ea9f JW |
1346 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
1347 | * @mem: the memory cgroup | |
19942822 | 1348 | * |
9d11ea9f | 1349 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1350 | * pages. |
19942822 | 1351 | */ |
c0ff4b85 | 1352 | static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) |
19942822 | 1353 | { |
9d11ea9f JW |
1354 | unsigned long long margin; |
1355 | ||
c0ff4b85 | 1356 | margin = res_counter_margin(&memcg->res); |
9d11ea9f | 1357 | if (do_swap_account) |
c0ff4b85 | 1358 | margin = min(margin, res_counter_margin(&memcg->memsw)); |
7ec99d62 | 1359 | return margin >> PAGE_SHIFT; |
19942822 JW |
1360 | } |
1361 | ||
1f4c025b | 1362 | int mem_cgroup_swappiness(struct mem_cgroup *memcg) |
a7885eb8 KM |
1363 | { |
1364 | struct cgroup *cgrp = memcg->css.cgroup; | |
a7885eb8 KM |
1365 | |
1366 | /* root ? */ | |
1367 | if (cgrp->parent == NULL) | |
1368 | return vm_swappiness; | |
1369 | ||
bf1ff263 | 1370 | return memcg->swappiness; |
a7885eb8 KM |
1371 | } |
1372 | ||
c0ff4b85 | 1373 | static void mem_cgroup_start_move(struct mem_cgroup *memcg) |
32047e2a KH |
1374 | { |
1375 | int cpu; | |
1489ebad KH |
1376 | |
1377 | get_online_cpus(); | |
c0ff4b85 | 1378 | spin_lock(&memcg->pcp_counter_lock); |
1489ebad | 1379 | for_each_online_cpu(cpu) |
c0ff4b85 R |
1380 | per_cpu(memcg->stat->count[MEM_CGROUP_ON_MOVE], cpu) += 1; |
1381 | memcg->nocpu_base.count[MEM_CGROUP_ON_MOVE] += 1; | |
1382 | spin_unlock(&memcg->pcp_counter_lock); | |
1489ebad | 1383 | put_online_cpus(); |
32047e2a KH |
1384 | |
1385 | synchronize_rcu(); | |
1386 | } | |
1387 | ||
c0ff4b85 | 1388 | static void mem_cgroup_end_move(struct mem_cgroup *memcg) |
32047e2a KH |
1389 | { |
1390 | int cpu; | |
1391 | ||
c0ff4b85 | 1392 | if (!memcg) |
32047e2a | 1393 | return; |
1489ebad | 1394 | get_online_cpus(); |
c0ff4b85 | 1395 | spin_lock(&memcg->pcp_counter_lock); |
1489ebad | 1396 | for_each_online_cpu(cpu) |
c0ff4b85 R |
1397 | per_cpu(memcg->stat->count[MEM_CGROUP_ON_MOVE], cpu) -= 1; |
1398 | memcg->nocpu_base.count[MEM_CGROUP_ON_MOVE] -= 1; | |
1399 | spin_unlock(&memcg->pcp_counter_lock); | |
1489ebad | 1400 | put_online_cpus(); |
32047e2a KH |
1401 | } |
1402 | /* | |
1403 | * 2 routines for checking "mem" is under move_account() or not. | |
1404 | * | |
1405 | * mem_cgroup_stealed() - checking a cgroup is mc.from or not. This is used | |
1406 | * for avoiding race in accounting. If true, | |
1407 | * pc->mem_cgroup may be overwritten. | |
1408 | * | |
1409 | * mem_cgroup_under_move() - checking a cgroup is mc.from or mc.to or | |
1410 | * under hierarchy of moving cgroups. This is for | |
1411 | * waiting at hith-memory prressure caused by "move". | |
1412 | */ | |
1413 | ||
c0ff4b85 | 1414 | static bool mem_cgroup_stealed(struct mem_cgroup *memcg) |
32047e2a KH |
1415 | { |
1416 | VM_BUG_ON(!rcu_read_lock_held()); | |
c0ff4b85 | 1417 | return this_cpu_read(memcg->stat->count[MEM_CGROUP_ON_MOVE]) > 0; |
32047e2a | 1418 | } |
4b534334 | 1419 | |
c0ff4b85 | 1420 | static bool mem_cgroup_under_move(struct mem_cgroup *memcg) |
4b534334 | 1421 | { |
2bd9bb20 KH |
1422 | struct mem_cgroup *from; |
1423 | struct mem_cgroup *to; | |
4b534334 | 1424 | bool ret = false; |
2bd9bb20 KH |
1425 | /* |
1426 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1427 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1428 | */ | |
1429 | spin_lock(&mc.lock); | |
1430 | from = mc.from; | |
1431 | to = mc.to; | |
1432 | if (!from) | |
1433 | goto unlock; | |
3e92041d | 1434 | |
c0ff4b85 R |
1435 | ret = mem_cgroup_same_or_subtree(memcg, from) |
1436 | || mem_cgroup_same_or_subtree(memcg, to); | |
2bd9bb20 KH |
1437 | unlock: |
1438 | spin_unlock(&mc.lock); | |
4b534334 KH |
1439 | return ret; |
1440 | } | |
1441 | ||
c0ff4b85 | 1442 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) |
4b534334 KH |
1443 | { |
1444 | if (mc.moving_task && current != mc.moving_task) { | |
c0ff4b85 | 1445 | if (mem_cgroup_under_move(memcg)) { |
4b534334 KH |
1446 | DEFINE_WAIT(wait); |
1447 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1448 | /* moving charge context might have finished. */ | |
1449 | if (mc.moving_task) | |
1450 | schedule(); | |
1451 | finish_wait(&mc.waitq, &wait); | |
1452 | return true; | |
1453 | } | |
1454 | } | |
1455 | return false; | |
1456 | } | |
1457 | ||
e222432b | 1458 | /** |
6a6135b6 | 1459 | * mem_cgroup_print_oom_info: Called from OOM with tasklist_lock held in read mode. |
e222432b BS |
1460 | * @memcg: The memory cgroup that went over limit |
1461 | * @p: Task that is going to be killed | |
1462 | * | |
1463 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1464 | * enabled | |
1465 | */ | |
1466 | void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) | |
1467 | { | |
1468 | struct cgroup *task_cgrp; | |
1469 | struct cgroup *mem_cgrp; | |
1470 | /* | |
1471 | * Need a buffer in BSS, can't rely on allocations. The code relies | |
1472 | * on the assumption that OOM is serialized for memory controller. | |
1473 | * If this assumption is broken, revisit this code. | |
1474 | */ | |
1475 | static char memcg_name[PATH_MAX]; | |
1476 | int ret; | |
1477 | ||
d31f56db | 1478 | if (!memcg || !p) |
e222432b BS |
1479 | return; |
1480 | ||
1481 | ||
1482 | rcu_read_lock(); | |
1483 | ||
1484 | mem_cgrp = memcg->css.cgroup; | |
1485 | task_cgrp = task_cgroup(p, mem_cgroup_subsys_id); | |
1486 | ||
1487 | ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX); | |
1488 | if (ret < 0) { | |
1489 | /* | |
1490 | * Unfortunately, we are unable to convert to a useful name | |
1491 | * But we'll still print out the usage information | |
1492 | */ | |
1493 | rcu_read_unlock(); | |
1494 | goto done; | |
1495 | } | |
1496 | rcu_read_unlock(); | |
1497 | ||
1498 | printk(KERN_INFO "Task in %s killed", memcg_name); | |
1499 | ||
1500 | rcu_read_lock(); | |
1501 | ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX); | |
1502 | if (ret < 0) { | |
1503 | rcu_read_unlock(); | |
1504 | goto done; | |
1505 | } | |
1506 | rcu_read_unlock(); | |
1507 | ||
1508 | /* | |
1509 | * Continues from above, so we don't need an KERN_ level | |
1510 | */ | |
1511 | printk(KERN_CONT " as a result of limit of %s\n", memcg_name); | |
1512 | done: | |
1513 | ||
1514 | printk(KERN_INFO "memory: usage %llukB, limit %llukB, failcnt %llu\n", | |
1515 | res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, | |
1516 | res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, | |
1517 | res_counter_read_u64(&memcg->res, RES_FAILCNT)); | |
1518 | printk(KERN_INFO "memory+swap: usage %llukB, limit %llukB, " | |
1519 | "failcnt %llu\n", | |
1520 | res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, | |
1521 | res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, | |
1522 | res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); | |
1523 | } | |
1524 | ||
81d39c20 KH |
1525 | /* |
1526 | * This function returns the number of memcg under hierarchy tree. Returns | |
1527 | * 1(self count) if no children. | |
1528 | */ | |
c0ff4b85 | 1529 | static int mem_cgroup_count_children(struct mem_cgroup *memcg) |
81d39c20 KH |
1530 | { |
1531 | int num = 0; | |
7d74b06f KH |
1532 | struct mem_cgroup *iter; |
1533 | ||
c0ff4b85 | 1534 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 1535 | num++; |
81d39c20 KH |
1536 | return num; |
1537 | } | |
1538 | ||
a63d83f4 DR |
1539 | /* |
1540 | * Return the memory (and swap, if configured) limit for a memcg. | |
1541 | */ | |
1542 | u64 mem_cgroup_get_limit(struct mem_cgroup *memcg) | |
1543 | { | |
1544 | u64 limit; | |
1545 | u64 memsw; | |
1546 | ||
f3e8eb70 JW |
1547 | limit = res_counter_read_u64(&memcg->res, RES_LIMIT); |
1548 | limit += total_swap_pages << PAGE_SHIFT; | |
1549 | ||
a63d83f4 DR |
1550 | memsw = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
1551 | /* | |
1552 | * If memsw is finite and limits the amount of swap space available | |
1553 | * to this memcg, return that limit. | |
1554 | */ | |
1555 | return min(limit, memsw); | |
1556 | } | |
1557 | ||
4d0c066d KH |
1558 | /** |
1559 | * test_mem_cgroup_node_reclaimable | |
1560 | * @mem: the target memcg | |
1561 | * @nid: the node ID to be checked. | |
1562 | * @noswap : specify true here if the user wants flle only information. | |
1563 | * | |
1564 | * This function returns whether the specified memcg contains any | |
1565 | * reclaimable pages on a node. Returns true if there are any reclaimable | |
1566 | * pages in the node. | |
1567 | */ | |
c0ff4b85 | 1568 | static bool test_mem_cgroup_node_reclaimable(struct mem_cgroup *memcg, |
4d0c066d KH |
1569 | int nid, bool noswap) |
1570 | { | |
c0ff4b85 | 1571 | if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_FILE)) |
4d0c066d KH |
1572 | return true; |
1573 | if (noswap || !total_swap_pages) | |
1574 | return false; | |
c0ff4b85 | 1575 | if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_ANON)) |
4d0c066d KH |
1576 | return true; |
1577 | return false; | |
1578 | ||
1579 | } | |
889976db YH |
1580 | #if MAX_NUMNODES > 1 |
1581 | ||
1582 | /* | |
1583 | * Always updating the nodemask is not very good - even if we have an empty | |
1584 | * list or the wrong list here, we can start from some node and traverse all | |
1585 | * nodes based on the zonelist. So update the list loosely once per 10 secs. | |
1586 | * | |
1587 | */ | |
c0ff4b85 | 1588 | static void mem_cgroup_may_update_nodemask(struct mem_cgroup *memcg) |
889976db YH |
1589 | { |
1590 | int nid; | |
453a9bf3 KH |
1591 | /* |
1592 | * numainfo_events > 0 means there was at least NUMAINFO_EVENTS_TARGET | |
1593 | * pagein/pageout changes since the last update. | |
1594 | */ | |
c0ff4b85 | 1595 | if (!atomic_read(&memcg->numainfo_events)) |
453a9bf3 | 1596 | return; |
c0ff4b85 | 1597 | if (atomic_inc_return(&memcg->numainfo_updating) > 1) |
889976db YH |
1598 | return; |
1599 | ||
889976db | 1600 | /* make a nodemask where this memcg uses memory from */ |
c0ff4b85 | 1601 | memcg->scan_nodes = node_states[N_HIGH_MEMORY]; |
889976db YH |
1602 | |
1603 | for_each_node_mask(nid, node_states[N_HIGH_MEMORY]) { | |
1604 | ||
c0ff4b85 R |
1605 | if (!test_mem_cgroup_node_reclaimable(memcg, nid, false)) |
1606 | node_clear(nid, memcg->scan_nodes); | |
889976db | 1607 | } |
453a9bf3 | 1608 | |
c0ff4b85 R |
1609 | atomic_set(&memcg->numainfo_events, 0); |
1610 | atomic_set(&memcg->numainfo_updating, 0); | |
889976db YH |
1611 | } |
1612 | ||
1613 | /* | |
1614 | * Selecting a node where we start reclaim from. Because what we need is just | |
1615 | * reducing usage counter, start from anywhere is O,K. Considering | |
1616 | * memory reclaim from current node, there are pros. and cons. | |
1617 | * | |
1618 | * Freeing memory from current node means freeing memory from a node which | |
1619 | * we'll use or we've used. So, it may make LRU bad. And if several threads | |
1620 | * hit limits, it will see a contention on a node. But freeing from remote | |
1621 | * node means more costs for memory reclaim because of memory latency. | |
1622 | * | |
1623 | * Now, we use round-robin. Better algorithm is welcomed. | |
1624 | */ | |
c0ff4b85 | 1625 | int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) |
889976db YH |
1626 | { |
1627 | int node; | |
1628 | ||
c0ff4b85 R |
1629 | mem_cgroup_may_update_nodemask(memcg); |
1630 | node = memcg->last_scanned_node; | |
889976db | 1631 | |
c0ff4b85 | 1632 | node = next_node(node, memcg->scan_nodes); |
889976db | 1633 | if (node == MAX_NUMNODES) |
c0ff4b85 | 1634 | node = first_node(memcg->scan_nodes); |
889976db YH |
1635 | /* |
1636 | * We call this when we hit limit, not when pages are added to LRU. | |
1637 | * No LRU may hold pages because all pages are UNEVICTABLE or | |
1638 | * memcg is too small and all pages are not on LRU. In that case, | |
1639 | * we use curret node. | |
1640 | */ | |
1641 | if (unlikely(node == MAX_NUMNODES)) | |
1642 | node = numa_node_id(); | |
1643 | ||
c0ff4b85 | 1644 | memcg->last_scanned_node = node; |
889976db YH |
1645 | return node; |
1646 | } | |
1647 | ||
4d0c066d KH |
1648 | /* |
1649 | * Check all nodes whether it contains reclaimable pages or not. | |
1650 | * For quick scan, we make use of scan_nodes. This will allow us to skip | |
1651 | * unused nodes. But scan_nodes is lazily updated and may not cotain | |
1652 | * enough new information. We need to do double check. | |
1653 | */ | |
c0ff4b85 | 1654 | bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) |
4d0c066d KH |
1655 | { |
1656 | int nid; | |
1657 | ||
1658 | /* | |
1659 | * quick check...making use of scan_node. | |
1660 | * We can skip unused nodes. | |
1661 | */ | |
c0ff4b85 R |
1662 | if (!nodes_empty(memcg->scan_nodes)) { |
1663 | for (nid = first_node(memcg->scan_nodes); | |
4d0c066d | 1664 | nid < MAX_NUMNODES; |
c0ff4b85 | 1665 | nid = next_node(nid, memcg->scan_nodes)) { |
4d0c066d | 1666 | |
c0ff4b85 | 1667 | if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap)) |
4d0c066d KH |
1668 | return true; |
1669 | } | |
1670 | } | |
1671 | /* | |
1672 | * Check rest of nodes. | |
1673 | */ | |
1674 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
c0ff4b85 | 1675 | if (node_isset(nid, memcg->scan_nodes)) |
4d0c066d | 1676 | continue; |
c0ff4b85 | 1677 | if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap)) |
4d0c066d KH |
1678 | return true; |
1679 | } | |
1680 | return false; | |
1681 | } | |
1682 | ||
889976db | 1683 | #else |
c0ff4b85 | 1684 | int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) |
889976db YH |
1685 | { |
1686 | return 0; | |
1687 | } | |
4d0c066d | 1688 | |
c0ff4b85 | 1689 | bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) |
4d0c066d | 1690 | { |
c0ff4b85 | 1691 | return test_mem_cgroup_node_reclaimable(memcg, 0, noswap); |
4d0c066d | 1692 | } |
889976db YH |
1693 | #endif |
1694 | ||
04046e1a KH |
1695 | /* |
1696 | * Scan the hierarchy if needed to reclaim memory. We remember the last child | |
1697 | * we reclaimed from, so that we don't end up penalizing one child extensively | |
1698 | * based on its position in the children list. | |
6d61ef40 | 1699 | * |
c0ff4b85 | 1700 | * root_memcg is the original ancestor that we've been reclaim from. |
04046e1a | 1701 | * |
c0ff4b85 | 1702 | * We give up and return to the caller when we visit root_memcg twice. |
04046e1a | 1703 | * (other groups can be removed while we're walking....) |
81d39c20 KH |
1704 | * |
1705 | * If shrink==true, for avoiding to free too much, this returns immedieately. | |
6d61ef40 | 1706 | */ |
c0ff4b85 | 1707 | static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_memcg, |
4e416953 | 1708 | struct zone *zone, |
75822b44 | 1709 | gfp_t gfp_mask, |
0ae5e89c YH |
1710 | unsigned long reclaim_options, |
1711 | unsigned long *total_scanned) | |
6d61ef40 | 1712 | { |
9f3a0d09 | 1713 | struct mem_cgroup *victim = NULL; |
04046e1a KH |
1714 | int ret, total = 0; |
1715 | int loop = 0; | |
75822b44 BS |
1716 | bool noswap = reclaim_options & MEM_CGROUP_RECLAIM_NOSWAP; |
1717 | bool shrink = reclaim_options & MEM_CGROUP_RECLAIM_SHRINK; | |
4e416953 | 1718 | bool check_soft = reclaim_options & MEM_CGROUP_RECLAIM_SOFT; |
9d11ea9f | 1719 | unsigned long excess; |
185efc0f | 1720 | unsigned long nr_scanned; |
527a5ec9 JW |
1721 | struct mem_cgroup_reclaim_cookie reclaim = { |
1722 | .zone = zone, | |
1723 | .priority = 0, | |
1724 | }; | |
9d11ea9f | 1725 | |
c0ff4b85 | 1726 | excess = res_counter_soft_limit_excess(&root_memcg->res) >> PAGE_SHIFT; |
04046e1a | 1727 | |
22a668d7 | 1728 | /* If memsw_is_minimum==1, swap-out is of-no-use. */ |
c0ff4b85 | 1729 | if (!check_soft && !shrink && root_memcg->memsw_is_minimum) |
22a668d7 KH |
1730 | noswap = true; |
1731 | ||
4e416953 | 1732 | while (1) { |
527a5ec9 | 1733 | victim = mem_cgroup_iter(root_memcg, victim, &reclaim); |
9f3a0d09 | 1734 | if (!victim) { |
04046e1a | 1735 | loop++; |
fbc29a25 KH |
1736 | /* |
1737 | * We are not draining per cpu cached charges during | |
1738 | * soft limit reclaim because global reclaim doesn't | |
1739 | * care about charges. It tries to free some memory and | |
1740 | * charges will not give any. | |
1741 | */ | |
1742 | if (!check_soft && loop >= 1) | |
c0ff4b85 | 1743 | drain_all_stock_async(root_memcg); |
4e416953 BS |
1744 | if (loop >= 2) { |
1745 | /* | |
1746 | * If we have not been able to reclaim | |
1747 | * anything, it might because there are | |
1748 | * no reclaimable pages under this hierarchy | |
1749 | */ | |
9f3a0d09 | 1750 | if (!check_soft || !total) |
4e416953 | 1751 | break; |
4e416953 | 1752 | /* |
25985edc | 1753 | * We want to do more targeted reclaim. |
4e416953 BS |
1754 | * excess >> 2 is not to excessive so as to |
1755 | * reclaim too much, nor too less that we keep | |
1756 | * coming back to reclaim from this cgroup | |
1757 | */ | |
1758 | if (total >= (excess >> 2) || | |
9f3a0d09 | 1759 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) |
4e416953 | 1760 | break; |
4e416953 | 1761 | } |
9f3a0d09 | 1762 | continue; |
4e416953 | 1763 | } |
4d0c066d | 1764 | if (!mem_cgroup_reclaimable(victim, noswap)) { |
04046e1a | 1765 | /* this cgroup's local usage == 0 */ |
6d61ef40 BS |
1766 | continue; |
1767 | } | |
04046e1a | 1768 | /* we use swappiness of local cgroup */ |
0ae5e89c | 1769 | if (check_soft) { |
4e416953 | 1770 | ret = mem_cgroup_shrink_node_zone(victim, gfp_mask, |
185efc0f JW |
1771 | noswap, zone, &nr_scanned); |
1772 | *total_scanned += nr_scanned; | |
0ae5e89c | 1773 | } else |
4e416953 | 1774 | ret = try_to_free_mem_cgroup_pages(victim, gfp_mask, |
185efc0f | 1775 | noswap); |
9f3a0d09 | 1776 | total += ret; |
81d39c20 KH |
1777 | /* |
1778 | * At shrinking usage, we can't check we should stop here or | |
1779 | * reclaim more. It's depends on callers. last_scanned_child | |
1780 | * will work enough for keeping fairness under tree. | |
1781 | */ | |
1782 | if (shrink) | |
9f3a0d09 | 1783 | break; |
4e416953 | 1784 | if (check_soft) { |
c0ff4b85 | 1785 | if (!res_counter_soft_limit_excess(&root_memcg->res)) |
9f3a0d09 | 1786 | break; |
c0ff4b85 | 1787 | } else if (mem_cgroup_margin(root_memcg)) |
9f3a0d09 | 1788 | break; |
6d61ef40 | 1789 | } |
9f3a0d09 | 1790 | mem_cgroup_iter_break(root_memcg, victim); |
04046e1a | 1791 | return total; |
6d61ef40 BS |
1792 | } |
1793 | ||
867578cb KH |
1794 | /* |
1795 | * Check OOM-Killer is already running under our hierarchy. | |
1796 | * If someone is running, return false. | |
1af8efe9 | 1797 | * Has to be called with memcg_oom_lock |
867578cb | 1798 | */ |
c0ff4b85 | 1799 | static bool mem_cgroup_oom_lock(struct mem_cgroup *memcg) |
867578cb | 1800 | { |
79dfdacc | 1801 | struct mem_cgroup *iter, *failed = NULL; |
a636b327 | 1802 | |
9f3a0d09 | 1803 | for_each_mem_cgroup_tree(iter, memcg) { |
23751be0 | 1804 | if (iter->oom_lock) { |
79dfdacc MH |
1805 | /* |
1806 | * this subtree of our hierarchy is already locked | |
1807 | * so we cannot give a lock. | |
1808 | */ | |
79dfdacc | 1809 | failed = iter; |
9f3a0d09 JW |
1810 | mem_cgroup_iter_break(memcg, iter); |
1811 | break; | |
23751be0 JW |
1812 | } else |
1813 | iter->oom_lock = true; | |
7d74b06f | 1814 | } |
867578cb | 1815 | |
79dfdacc | 1816 | if (!failed) |
23751be0 | 1817 | return true; |
79dfdacc MH |
1818 | |
1819 | /* | |
1820 | * OK, we failed to lock the whole subtree so we have to clean up | |
1821 | * what we set up to the failing subtree | |
1822 | */ | |
9f3a0d09 | 1823 | for_each_mem_cgroup_tree(iter, memcg) { |
79dfdacc | 1824 | if (iter == failed) { |
9f3a0d09 JW |
1825 | mem_cgroup_iter_break(memcg, iter); |
1826 | break; | |
79dfdacc MH |
1827 | } |
1828 | iter->oom_lock = false; | |
1829 | } | |
23751be0 | 1830 | return false; |
a636b327 | 1831 | } |
0b7f569e | 1832 | |
79dfdacc | 1833 | /* |
1af8efe9 | 1834 | * Has to be called with memcg_oom_lock |
79dfdacc | 1835 | */ |
c0ff4b85 | 1836 | static int mem_cgroup_oom_unlock(struct mem_cgroup *memcg) |
0b7f569e | 1837 | { |
7d74b06f KH |
1838 | struct mem_cgroup *iter; |
1839 | ||
c0ff4b85 | 1840 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc MH |
1841 | iter->oom_lock = false; |
1842 | return 0; | |
1843 | } | |
1844 | ||
c0ff4b85 | 1845 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1846 | { |
1847 | struct mem_cgroup *iter; | |
1848 | ||
c0ff4b85 | 1849 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc MH |
1850 | atomic_inc(&iter->under_oom); |
1851 | } | |
1852 | ||
c0ff4b85 | 1853 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg) |
79dfdacc MH |
1854 | { |
1855 | struct mem_cgroup *iter; | |
1856 | ||
867578cb KH |
1857 | /* |
1858 | * When a new child is created while the hierarchy is under oom, | |
1859 | * mem_cgroup_oom_lock() may not be called. We have to use | |
1860 | * atomic_add_unless() here. | |
1861 | */ | |
c0ff4b85 | 1862 | for_each_mem_cgroup_tree(iter, memcg) |
79dfdacc | 1863 | atomic_add_unless(&iter->under_oom, -1, 0); |
0b7f569e KH |
1864 | } |
1865 | ||
1af8efe9 | 1866 | static DEFINE_SPINLOCK(memcg_oom_lock); |
867578cb KH |
1867 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1868 | ||
dc98df5a KH |
1869 | struct oom_wait_info { |
1870 | struct mem_cgroup *mem; | |
1871 | wait_queue_t wait; | |
1872 | }; | |
1873 | ||
1874 | static int memcg_oom_wake_function(wait_queue_t *wait, | |
1875 | unsigned mode, int sync, void *arg) | |
1876 | { | |
c0ff4b85 R |
1877 | struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg, |
1878 | *oom_wait_memcg; | |
dc98df5a KH |
1879 | struct oom_wait_info *oom_wait_info; |
1880 | ||
1881 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
c0ff4b85 | 1882 | oom_wait_memcg = oom_wait_info->mem; |
dc98df5a | 1883 | |
dc98df5a KH |
1884 | /* |
1885 | * Both of oom_wait_info->mem and wake_mem are stable under us. | |
1886 | * Then we can use css_is_ancestor without taking care of RCU. | |
1887 | */ | |
c0ff4b85 R |
1888 | if (!mem_cgroup_same_or_subtree(oom_wait_memcg, wake_memcg) |
1889 | && !mem_cgroup_same_or_subtree(wake_memcg, oom_wait_memcg)) | |
dc98df5a | 1890 | return 0; |
dc98df5a KH |
1891 | return autoremove_wake_function(wait, mode, sync, arg); |
1892 | } | |
1893 | ||
c0ff4b85 | 1894 | static void memcg_wakeup_oom(struct mem_cgroup *memcg) |
dc98df5a | 1895 | { |
c0ff4b85 R |
1896 | /* for filtering, pass "memcg" as argument. */ |
1897 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg); | |
dc98df5a KH |
1898 | } |
1899 | ||
c0ff4b85 | 1900 | static void memcg_oom_recover(struct mem_cgroup *memcg) |
3c11ecf4 | 1901 | { |
c0ff4b85 R |
1902 | if (memcg && atomic_read(&memcg->under_oom)) |
1903 | memcg_wakeup_oom(memcg); | |
3c11ecf4 KH |
1904 | } |
1905 | ||
867578cb KH |
1906 | /* |
1907 | * try to call OOM killer. returns false if we should exit memory-reclaim loop. | |
1908 | */ | |
c0ff4b85 | 1909 | bool mem_cgroup_handle_oom(struct mem_cgroup *memcg, gfp_t mask) |
0b7f569e | 1910 | { |
dc98df5a | 1911 | struct oom_wait_info owait; |
3c11ecf4 | 1912 | bool locked, need_to_kill; |
867578cb | 1913 | |
c0ff4b85 | 1914 | owait.mem = memcg; |
dc98df5a KH |
1915 | owait.wait.flags = 0; |
1916 | owait.wait.func = memcg_oom_wake_function; | |
1917 | owait.wait.private = current; | |
1918 | INIT_LIST_HEAD(&owait.wait.task_list); | |
3c11ecf4 | 1919 | need_to_kill = true; |
c0ff4b85 | 1920 | mem_cgroup_mark_under_oom(memcg); |
79dfdacc | 1921 | |
c0ff4b85 | 1922 | /* At first, try to OOM lock hierarchy under memcg.*/ |
1af8efe9 | 1923 | spin_lock(&memcg_oom_lock); |
c0ff4b85 | 1924 | locked = mem_cgroup_oom_lock(memcg); |
867578cb KH |
1925 | /* |
1926 | * Even if signal_pending(), we can't quit charge() loop without | |
1927 | * accounting. So, UNINTERRUPTIBLE is appropriate. But SIGKILL | |
1928 | * under OOM is always welcomed, use TASK_KILLABLE here. | |
1929 | */ | |
3c11ecf4 | 1930 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
c0ff4b85 | 1931 | if (!locked || memcg->oom_kill_disable) |
3c11ecf4 KH |
1932 | need_to_kill = false; |
1933 | if (locked) | |
c0ff4b85 | 1934 | mem_cgroup_oom_notify(memcg); |
1af8efe9 | 1935 | spin_unlock(&memcg_oom_lock); |
867578cb | 1936 | |
3c11ecf4 KH |
1937 | if (need_to_kill) { |
1938 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
c0ff4b85 | 1939 | mem_cgroup_out_of_memory(memcg, mask); |
3c11ecf4 | 1940 | } else { |
867578cb | 1941 | schedule(); |
dc98df5a | 1942 | finish_wait(&memcg_oom_waitq, &owait.wait); |
867578cb | 1943 | } |
1af8efe9 | 1944 | spin_lock(&memcg_oom_lock); |
79dfdacc | 1945 | if (locked) |
c0ff4b85 R |
1946 | mem_cgroup_oom_unlock(memcg); |
1947 | memcg_wakeup_oom(memcg); | |
1af8efe9 | 1948 | spin_unlock(&memcg_oom_lock); |
867578cb | 1949 | |
c0ff4b85 | 1950 | mem_cgroup_unmark_under_oom(memcg); |
79dfdacc | 1951 | |
867578cb KH |
1952 | if (test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current)) |
1953 | return false; | |
1954 | /* Give chance to dying process */ | |
715a5ee8 | 1955 | schedule_timeout_uninterruptible(1); |
867578cb | 1956 | return true; |
0b7f569e KH |
1957 | } |
1958 | ||
d69b042f BS |
1959 | /* |
1960 | * Currently used to update mapped file statistics, but the routine can be | |
1961 | * generalized to update other statistics as well. | |
32047e2a KH |
1962 | * |
1963 | * Notes: Race condition | |
1964 | * | |
1965 | * We usually use page_cgroup_lock() for accessing page_cgroup member but | |
1966 | * it tends to be costly. But considering some conditions, we doesn't need | |
1967 | * to do so _always_. | |
1968 | * | |
1969 | * Considering "charge", lock_page_cgroup() is not required because all | |
1970 | * file-stat operations happen after a page is attached to radix-tree. There | |
1971 | * are no race with "charge". | |
1972 | * | |
1973 | * Considering "uncharge", we know that memcg doesn't clear pc->mem_cgroup | |
1974 | * at "uncharge" intentionally. So, we always see valid pc->mem_cgroup even | |
1975 | * if there are race with "uncharge". Statistics itself is properly handled | |
1976 | * by flags. | |
1977 | * | |
1978 | * Considering "move", this is an only case we see a race. To make the race | |
1979 | * small, we check MEM_CGROUP_ON_MOVE percpu value and detect there are | |
1980 | * possibility of race condition. If there is, we take a lock. | |
d69b042f | 1981 | */ |
26174efd | 1982 | |
2a7106f2 GT |
1983 | void mem_cgroup_update_page_stat(struct page *page, |
1984 | enum mem_cgroup_page_stat_item idx, int val) | |
d69b042f | 1985 | { |
c0ff4b85 | 1986 | struct mem_cgroup *memcg; |
32047e2a KH |
1987 | struct page_cgroup *pc = lookup_page_cgroup(page); |
1988 | bool need_unlock = false; | |
dbd4ea78 | 1989 | unsigned long uninitialized_var(flags); |
d69b042f | 1990 | |
d69b042f BS |
1991 | if (unlikely(!pc)) |
1992 | return; | |
1993 | ||
32047e2a | 1994 | rcu_read_lock(); |
c0ff4b85 R |
1995 | memcg = pc->mem_cgroup; |
1996 | if (unlikely(!memcg || !PageCgroupUsed(pc))) | |
32047e2a KH |
1997 | goto out; |
1998 | /* pc->mem_cgroup is unstable ? */ | |
c0ff4b85 | 1999 | if (unlikely(mem_cgroup_stealed(memcg)) || PageTransHuge(page)) { |
32047e2a | 2000 | /* take a lock against to access pc->mem_cgroup */ |
dbd4ea78 | 2001 | move_lock_page_cgroup(pc, &flags); |
32047e2a | 2002 | need_unlock = true; |
c0ff4b85 R |
2003 | memcg = pc->mem_cgroup; |
2004 | if (!memcg || !PageCgroupUsed(pc)) | |
32047e2a KH |
2005 | goto out; |
2006 | } | |
26174efd | 2007 | |
26174efd | 2008 | switch (idx) { |
2a7106f2 | 2009 | case MEMCG_NR_FILE_MAPPED: |
26174efd KH |
2010 | if (val > 0) |
2011 | SetPageCgroupFileMapped(pc); | |
2012 | else if (!page_mapped(page)) | |
0c270f8f | 2013 | ClearPageCgroupFileMapped(pc); |
2a7106f2 | 2014 | idx = MEM_CGROUP_STAT_FILE_MAPPED; |
26174efd KH |
2015 | break; |
2016 | default: | |
2017 | BUG(); | |
8725d541 | 2018 | } |
d69b042f | 2019 | |
c0ff4b85 | 2020 | this_cpu_add(memcg->stat->count[idx], val); |
2a7106f2 | 2021 | |
32047e2a KH |
2022 | out: |
2023 | if (unlikely(need_unlock)) | |
dbd4ea78 | 2024 | move_unlock_page_cgroup(pc, &flags); |
32047e2a KH |
2025 | rcu_read_unlock(); |
2026 | return; | |
d69b042f | 2027 | } |
2a7106f2 | 2028 | EXPORT_SYMBOL(mem_cgroup_update_page_stat); |
26174efd | 2029 | |
cdec2e42 KH |
2030 | /* |
2031 | * size of first charge trial. "32" comes from vmscan.c's magic value. | |
2032 | * TODO: maybe necessary to use big numbers in big irons. | |
2033 | */ | |
7ec99d62 | 2034 | #define CHARGE_BATCH 32U |
cdec2e42 KH |
2035 | struct memcg_stock_pcp { |
2036 | struct mem_cgroup *cached; /* this never be root cgroup */ | |
11c9ea4e | 2037 | unsigned int nr_pages; |
cdec2e42 | 2038 | struct work_struct work; |
26fe6168 KH |
2039 | unsigned long flags; |
2040 | #define FLUSHING_CACHED_CHARGE (0) | |
cdec2e42 KH |
2041 | }; |
2042 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); | |
9f50fad6 | 2043 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 KH |
2044 | |
2045 | /* | |
11c9ea4e | 2046 | * Try to consume stocked charge on this cpu. If success, one page is consumed |
cdec2e42 KH |
2047 | * from local stock and true is returned. If the stock is 0 or charges from a |
2048 | * cgroup which is not current target, returns false. This stock will be | |
2049 | * refilled. | |
2050 | */ | |
c0ff4b85 | 2051 | static bool consume_stock(struct mem_cgroup *memcg) |
cdec2e42 KH |
2052 | { |
2053 | struct memcg_stock_pcp *stock; | |
2054 | bool ret = true; | |
2055 | ||
2056 | stock = &get_cpu_var(memcg_stock); | |
c0ff4b85 | 2057 | if (memcg == stock->cached && stock->nr_pages) |
11c9ea4e | 2058 | stock->nr_pages--; |
cdec2e42 KH |
2059 | else /* need to call res_counter_charge */ |
2060 | ret = false; | |
2061 | put_cpu_var(memcg_stock); | |
2062 | return ret; | |
2063 | } | |
2064 | ||
2065 | /* | |
2066 | * Returns stocks cached in percpu to res_counter and reset cached information. | |
2067 | */ | |
2068 | static void drain_stock(struct memcg_stock_pcp *stock) | |
2069 | { | |
2070 | struct mem_cgroup *old = stock->cached; | |
2071 | ||
11c9ea4e JW |
2072 | if (stock->nr_pages) { |
2073 | unsigned long bytes = stock->nr_pages * PAGE_SIZE; | |
2074 | ||
2075 | res_counter_uncharge(&old->res, bytes); | |
cdec2e42 | 2076 | if (do_swap_account) |
11c9ea4e JW |
2077 | res_counter_uncharge(&old->memsw, bytes); |
2078 | stock->nr_pages = 0; | |
cdec2e42 KH |
2079 | } |
2080 | stock->cached = NULL; | |
cdec2e42 KH |
2081 | } |
2082 | ||
2083 | /* | |
2084 | * This must be called under preempt disabled or must be called by | |
2085 | * a thread which is pinned to local cpu. | |
2086 | */ | |
2087 | static void drain_local_stock(struct work_struct *dummy) | |
2088 | { | |
2089 | struct memcg_stock_pcp *stock = &__get_cpu_var(memcg_stock); | |
2090 | drain_stock(stock); | |
26fe6168 | 2091 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
cdec2e42 KH |
2092 | } |
2093 | ||
2094 | /* | |
2095 | * Cache charges(val) which is from res_counter, to local per_cpu area. | |
320cc51d | 2096 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 2097 | */ |
c0ff4b85 | 2098 | static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) |
cdec2e42 KH |
2099 | { |
2100 | struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock); | |
2101 | ||
c0ff4b85 | 2102 | if (stock->cached != memcg) { /* reset if necessary */ |
cdec2e42 | 2103 | drain_stock(stock); |
c0ff4b85 | 2104 | stock->cached = memcg; |
cdec2e42 | 2105 | } |
11c9ea4e | 2106 | stock->nr_pages += nr_pages; |
cdec2e42 KH |
2107 | put_cpu_var(memcg_stock); |
2108 | } | |
2109 | ||
2110 | /* | |
c0ff4b85 | 2111 | * Drains all per-CPU charge caches for given root_memcg resp. subtree |
d38144b7 MH |
2112 | * of the hierarchy under it. sync flag says whether we should block |
2113 | * until the work is done. | |
cdec2e42 | 2114 | */ |
c0ff4b85 | 2115 | static void drain_all_stock(struct mem_cgroup *root_memcg, bool sync) |
cdec2e42 | 2116 | { |
26fe6168 | 2117 | int cpu, curcpu; |
d38144b7 | 2118 | |
cdec2e42 | 2119 | /* Notify other cpus that system-wide "drain" is running */ |
cdec2e42 | 2120 | get_online_cpus(); |
5af12d0e | 2121 | curcpu = get_cpu(); |
cdec2e42 KH |
2122 | for_each_online_cpu(cpu) { |
2123 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
c0ff4b85 | 2124 | struct mem_cgroup *memcg; |
26fe6168 | 2125 | |
c0ff4b85 R |
2126 | memcg = stock->cached; |
2127 | if (!memcg || !stock->nr_pages) | |
26fe6168 | 2128 | continue; |
c0ff4b85 | 2129 | if (!mem_cgroup_same_or_subtree(root_memcg, memcg)) |
3e92041d | 2130 | continue; |
d1a05b69 MH |
2131 | if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { |
2132 | if (cpu == curcpu) | |
2133 | drain_local_stock(&stock->work); | |
2134 | else | |
2135 | schedule_work_on(cpu, &stock->work); | |
2136 | } | |
cdec2e42 | 2137 | } |
5af12d0e | 2138 | put_cpu(); |
d38144b7 MH |
2139 | |
2140 | if (!sync) | |
2141 | goto out; | |
2142 | ||
2143 | for_each_online_cpu(cpu) { | |
2144 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
9f50fad6 | 2145 | if (test_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) |
d38144b7 MH |
2146 | flush_work(&stock->work); |
2147 | } | |
2148 | out: | |
cdec2e42 | 2149 | put_online_cpus(); |
d38144b7 MH |
2150 | } |
2151 | ||
2152 | /* | |
2153 | * Tries to drain stocked charges in other cpus. This function is asynchronous | |
2154 | * and just put a work per cpu for draining localy on each cpu. Caller can | |
2155 | * expects some charges will be back to res_counter later but cannot wait for | |
2156 | * it. | |
2157 | */ | |
c0ff4b85 | 2158 | static void drain_all_stock_async(struct mem_cgroup *root_memcg) |
d38144b7 | 2159 | { |
9f50fad6 MH |
2160 | /* |
2161 | * If someone calls draining, avoid adding more kworker runs. | |
2162 | */ | |
2163 | if (!mutex_trylock(&percpu_charge_mutex)) | |
2164 | return; | |
c0ff4b85 | 2165 | drain_all_stock(root_memcg, false); |
9f50fad6 | 2166 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2167 | } |
2168 | ||
2169 | /* This is a synchronous drain interface. */ | |
c0ff4b85 | 2170 | static void drain_all_stock_sync(struct mem_cgroup *root_memcg) |
cdec2e42 KH |
2171 | { |
2172 | /* called when force_empty is called */ | |
9f50fad6 | 2173 | mutex_lock(&percpu_charge_mutex); |
c0ff4b85 | 2174 | drain_all_stock(root_memcg, true); |
9f50fad6 | 2175 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2176 | } |
2177 | ||
711d3d2c KH |
2178 | /* |
2179 | * This function drains percpu counter value from DEAD cpu and | |
2180 | * move it to local cpu. Note that this function can be preempted. | |
2181 | */ | |
c0ff4b85 | 2182 | static void mem_cgroup_drain_pcp_counter(struct mem_cgroup *memcg, int cpu) |
711d3d2c KH |
2183 | { |
2184 | int i; | |
2185 | ||
c0ff4b85 | 2186 | spin_lock(&memcg->pcp_counter_lock); |
711d3d2c | 2187 | for (i = 0; i < MEM_CGROUP_STAT_DATA; i++) { |
c0ff4b85 | 2188 | long x = per_cpu(memcg->stat->count[i], cpu); |
711d3d2c | 2189 | |
c0ff4b85 R |
2190 | per_cpu(memcg->stat->count[i], cpu) = 0; |
2191 | memcg->nocpu_base.count[i] += x; | |
711d3d2c | 2192 | } |
e9f8974f | 2193 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) { |
c0ff4b85 | 2194 | unsigned long x = per_cpu(memcg->stat->events[i], cpu); |
e9f8974f | 2195 | |
c0ff4b85 R |
2196 | per_cpu(memcg->stat->events[i], cpu) = 0; |
2197 | memcg->nocpu_base.events[i] += x; | |
e9f8974f | 2198 | } |
1489ebad | 2199 | /* need to clear ON_MOVE value, works as a kind of lock. */ |
c0ff4b85 R |
2200 | per_cpu(memcg->stat->count[MEM_CGROUP_ON_MOVE], cpu) = 0; |
2201 | spin_unlock(&memcg->pcp_counter_lock); | |
1489ebad KH |
2202 | } |
2203 | ||
c0ff4b85 | 2204 | static void synchronize_mem_cgroup_on_move(struct mem_cgroup *memcg, int cpu) |
1489ebad KH |
2205 | { |
2206 | int idx = MEM_CGROUP_ON_MOVE; | |
2207 | ||
c0ff4b85 R |
2208 | spin_lock(&memcg->pcp_counter_lock); |
2209 | per_cpu(memcg->stat->count[idx], cpu) = memcg->nocpu_base.count[idx]; | |
2210 | spin_unlock(&memcg->pcp_counter_lock); | |
711d3d2c KH |
2211 | } |
2212 | ||
2213 | static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, | |
cdec2e42 KH |
2214 | unsigned long action, |
2215 | void *hcpu) | |
2216 | { | |
2217 | int cpu = (unsigned long)hcpu; | |
2218 | struct memcg_stock_pcp *stock; | |
711d3d2c | 2219 | struct mem_cgroup *iter; |
cdec2e42 | 2220 | |
1489ebad | 2221 | if ((action == CPU_ONLINE)) { |
9f3a0d09 | 2222 | for_each_mem_cgroup(iter) |
1489ebad KH |
2223 | synchronize_mem_cgroup_on_move(iter, cpu); |
2224 | return NOTIFY_OK; | |
2225 | } | |
2226 | ||
711d3d2c | 2227 | if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN) |
cdec2e42 | 2228 | return NOTIFY_OK; |
711d3d2c | 2229 | |
9f3a0d09 | 2230 | for_each_mem_cgroup(iter) |
711d3d2c KH |
2231 | mem_cgroup_drain_pcp_counter(iter, cpu); |
2232 | ||
cdec2e42 KH |
2233 | stock = &per_cpu(memcg_stock, cpu); |
2234 | drain_stock(stock); | |
2235 | return NOTIFY_OK; | |
2236 | } | |
2237 | ||
4b534334 KH |
2238 | |
2239 | /* See __mem_cgroup_try_charge() for details */ | |
2240 | enum { | |
2241 | CHARGE_OK, /* success */ | |
2242 | CHARGE_RETRY, /* need to retry but retry is not bad */ | |
2243 | CHARGE_NOMEM, /* we can't do more. return -ENOMEM */ | |
2244 | CHARGE_WOULDBLOCK, /* GFP_WAIT wasn't set and no enough res. */ | |
2245 | CHARGE_OOM_DIE, /* the current is killed because of OOM */ | |
2246 | }; | |
2247 | ||
c0ff4b85 | 2248 | static int mem_cgroup_do_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, |
7ec99d62 | 2249 | unsigned int nr_pages, bool oom_check) |
4b534334 | 2250 | { |
7ec99d62 | 2251 | unsigned long csize = nr_pages * PAGE_SIZE; |
4b534334 KH |
2252 | struct mem_cgroup *mem_over_limit; |
2253 | struct res_counter *fail_res; | |
2254 | unsigned long flags = 0; | |
2255 | int ret; | |
2256 | ||
c0ff4b85 | 2257 | ret = res_counter_charge(&memcg->res, csize, &fail_res); |
4b534334 KH |
2258 | |
2259 | if (likely(!ret)) { | |
2260 | if (!do_swap_account) | |
2261 | return CHARGE_OK; | |
c0ff4b85 | 2262 | ret = res_counter_charge(&memcg->memsw, csize, &fail_res); |
4b534334 KH |
2263 | if (likely(!ret)) |
2264 | return CHARGE_OK; | |
2265 | ||
c0ff4b85 | 2266 | res_counter_uncharge(&memcg->res, csize); |
4b534334 KH |
2267 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw); |
2268 | flags |= MEM_CGROUP_RECLAIM_NOSWAP; | |
2269 | } else | |
2270 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, res); | |
9221edb7 | 2271 | /* |
7ec99d62 JW |
2272 | * nr_pages can be either a huge page (HPAGE_PMD_NR), a batch |
2273 | * of regular pages (CHARGE_BATCH), or a single regular page (1). | |
9221edb7 JW |
2274 | * |
2275 | * Never reclaim on behalf of optional batching, retry with a | |
2276 | * single page instead. | |
2277 | */ | |
7ec99d62 | 2278 | if (nr_pages == CHARGE_BATCH) |
4b534334 KH |
2279 | return CHARGE_RETRY; |
2280 | ||
2281 | if (!(gfp_mask & __GFP_WAIT)) | |
2282 | return CHARGE_WOULDBLOCK; | |
2283 | ||
2284 | ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, NULL, | |
0ae5e89c | 2285 | gfp_mask, flags, NULL); |
7ec99d62 | 2286 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
19942822 | 2287 | return CHARGE_RETRY; |
4b534334 | 2288 | /* |
19942822 JW |
2289 | * Even though the limit is exceeded at this point, reclaim |
2290 | * may have been able to free some pages. Retry the charge | |
2291 | * before killing the task. | |
2292 | * | |
2293 | * Only for regular pages, though: huge pages are rather | |
2294 | * unlikely to succeed so close to the limit, and we fall back | |
2295 | * to regular pages anyway in case of failure. | |
4b534334 | 2296 | */ |
7ec99d62 | 2297 | if (nr_pages == 1 && ret) |
4b534334 KH |
2298 | return CHARGE_RETRY; |
2299 | ||
2300 | /* | |
2301 | * At task move, charge accounts can be doubly counted. So, it's | |
2302 | * better to wait until the end of task_move if something is going on. | |
2303 | */ | |
2304 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2305 | return CHARGE_RETRY; | |
2306 | ||
2307 | /* If we don't need to call oom-killer at el, return immediately */ | |
2308 | if (!oom_check) | |
2309 | return CHARGE_NOMEM; | |
2310 | /* check OOM */ | |
2311 | if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask)) | |
2312 | return CHARGE_OOM_DIE; | |
2313 | ||
2314 | return CHARGE_RETRY; | |
2315 | } | |
2316 | ||
f817ed48 KH |
2317 | /* |
2318 | * Unlike exported interface, "oom" parameter is added. if oom==true, | |
2319 | * oom-killer can be invoked. | |
8a9f3ccd | 2320 | */ |
f817ed48 | 2321 | static int __mem_cgroup_try_charge(struct mm_struct *mm, |
ec168510 | 2322 | gfp_t gfp_mask, |
7ec99d62 | 2323 | unsigned int nr_pages, |
c0ff4b85 | 2324 | struct mem_cgroup **ptr, |
7ec99d62 | 2325 | bool oom) |
8a9f3ccd | 2326 | { |
7ec99d62 | 2327 | unsigned int batch = max(CHARGE_BATCH, nr_pages); |
4b534334 | 2328 | int nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; |
c0ff4b85 | 2329 | struct mem_cgroup *memcg = NULL; |
4b534334 | 2330 | int ret; |
a636b327 | 2331 | |
867578cb KH |
2332 | /* |
2333 | * Unlike gloval-vm's OOM-kill, we're not in memory shortage | |
2334 | * in system level. So, allow to go ahead dying process in addition to | |
2335 | * MEMDIE process. | |
2336 | */ | |
2337 | if (unlikely(test_thread_flag(TIF_MEMDIE) | |
2338 | || fatal_signal_pending(current))) | |
2339 | goto bypass; | |
a636b327 | 2340 | |
8a9f3ccd | 2341 | /* |
3be91277 HD |
2342 | * We always charge the cgroup the mm_struct belongs to. |
2343 | * The mm_struct's mem_cgroup changes on task migration if the | |
8a9f3ccd BS |
2344 | * thread group leader migrates. It's possible that mm is not |
2345 | * set, if so charge the init_mm (happens for pagecache usage). | |
2346 | */ | |
c0ff4b85 | 2347 | if (!*ptr && !mm) |
f75ca962 KH |
2348 | goto bypass; |
2349 | again: | |
c0ff4b85 R |
2350 | if (*ptr) { /* css should be a valid one */ |
2351 | memcg = *ptr; | |
2352 | VM_BUG_ON(css_is_removed(&memcg->css)); | |
2353 | if (mem_cgroup_is_root(memcg)) | |
f75ca962 | 2354 | goto done; |
c0ff4b85 | 2355 | if (nr_pages == 1 && consume_stock(memcg)) |
f75ca962 | 2356 | goto done; |
c0ff4b85 | 2357 | css_get(&memcg->css); |
4b534334 | 2358 | } else { |
f75ca962 | 2359 | struct task_struct *p; |
54595fe2 | 2360 | |
f75ca962 KH |
2361 | rcu_read_lock(); |
2362 | p = rcu_dereference(mm->owner); | |
f75ca962 | 2363 | /* |
ebb76ce1 | 2364 | * Because we don't have task_lock(), "p" can exit. |
c0ff4b85 | 2365 | * In that case, "memcg" can point to root or p can be NULL with |
ebb76ce1 KH |
2366 | * race with swapoff. Then, we have small risk of mis-accouning. |
2367 | * But such kind of mis-account by race always happens because | |
2368 | * we don't have cgroup_mutex(). It's overkill and we allo that | |
2369 | * small race, here. | |
2370 | * (*) swapoff at el will charge against mm-struct not against | |
2371 | * task-struct. So, mm->owner can be NULL. | |
f75ca962 | 2372 | */ |
c0ff4b85 R |
2373 | memcg = mem_cgroup_from_task(p); |
2374 | if (!memcg || mem_cgroup_is_root(memcg)) { | |
f75ca962 KH |
2375 | rcu_read_unlock(); |
2376 | goto done; | |
2377 | } | |
c0ff4b85 | 2378 | if (nr_pages == 1 && consume_stock(memcg)) { |
f75ca962 KH |
2379 | /* |
2380 | * It seems dagerous to access memcg without css_get(). | |
2381 | * But considering how consume_stok works, it's not | |
2382 | * necessary. If consume_stock success, some charges | |
2383 | * from this memcg are cached on this cpu. So, we | |
2384 | * don't need to call css_get()/css_tryget() before | |
2385 | * calling consume_stock(). | |
2386 | */ | |
2387 | rcu_read_unlock(); | |
2388 | goto done; | |
2389 | } | |
2390 | /* after here, we may be blocked. we need to get refcnt */ | |
c0ff4b85 | 2391 | if (!css_tryget(&memcg->css)) { |
f75ca962 KH |
2392 | rcu_read_unlock(); |
2393 | goto again; | |
2394 | } | |
2395 | rcu_read_unlock(); | |
2396 | } | |
8a9f3ccd | 2397 | |
4b534334 KH |
2398 | do { |
2399 | bool oom_check; | |
7a81b88c | 2400 | |
4b534334 | 2401 | /* If killed, bypass charge */ |
f75ca962 | 2402 | if (fatal_signal_pending(current)) { |
c0ff4b85 | 2403 | css_put(&memcg->css); |
4b534334 | 2404 | goto bypass; |
f75ca962 | 2405 | } |
6d61ef40 | 2406 | |
4b534334 KH |
2407 | oom_check = false; |
2408 | if (oom && !nr_oom_retries) { | |
2409 | oom_check = true; | |
2410 | nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
cdec2e42 | 2411 | } |
66e1707b | 2412 | |
c0ff4b85 | 2413 | ret = mem_cgroup_do_charge(memcg, gfp_mask, batch, oom_check); |
4b534334 KH |
2414 | switch (ret) { |
2415 | case CHARGE_OK: | |
2416 | break; | |
2417 | case CHARGE_RETRY: /* not in OOM situation but retry */ | |
7ec99d62 | 2418 | batch = nr_pages; |
c0ff4b85 R |
2419 | css_put(&memcg->css); |
2420 | memcg = NULL; | |
f75ca962 | 2421 | goto again; |
4b534334 | 2422 | case CHARGE_WOULDBLOCK: /* !__GFP_WAIT */ |
c0ff4b85 | 2423 | css_put(&memcg->css); |
4b534334 KH |
2424 | goto nomem; |
2425 | case CHARGE_NOMEM: /* OOM routine works */ | |
f75ca962 | 2426 | if (!oom) { |
c0ff4b85 | 2427 | css_put(&memcg->css); |
867578cb | 2428 | goto nomem; |
f75ca962 | 2429 | } |
4b534334 KH |
2430 | /* If oom, we never return -ENOMEM */ |
2431 | nr_oom_retries--; | |
2432 | break; | |
2433 | case CHARGE_OOM_DIE: /* Killed by OOM Killer */ | |
c0ff4b85 | 2434 | css_put(&memcg->css); |
867578cb | 2435 | goto bypass; |
66e1707b | 2436 | } |
4b534334 KH |
2437 | } while (ret != CHARGE_OK); |
2438 | ||
7ec99d62 | 2439 | if (batch > nr_pages) |
c0ff4b85 R |
2440 | refill_stock(memcg, batch - nr_pages); |
2441 | css_put(&memcg->css); | |
0c3e73e8 | 2442 | done: |
c0ff4b85 | 2443 | *ptr = memcg; |
7a81b88c KH |
2444 | return 0; |
2445 | nomem: | |
c0ff4b85 | 2446 | *ptr = NULL; |
7a81b88c | 2447 | return -ENOMEM; |
867578cb | 2448 | bypass: |
c0ff4b85 | 2449 | *ptr = NULL; |
867578cb | 2450 | return 0; |
7a81b88c | 2451 | } |
8a9f3ccd | 2452 | |
a3032a2c DN |
2453 | /* |
2454 | * Somemtimes we have to undo a charge we got by try_charge(). | |
2455 | * This function is for that and do uncharge, put css's refcnt. | |
2456 | * gotten by try_charge(). | |
2457 | */ | |
c0ff4b85 | 2458 | static void __mem_cgroup_cancel_charge(struct mem_cgroup *memcg, |
e7018b8d | 2459 | unsigned int nr_pages) |
a3032a2c | 2460 | { |
c0ff4b85 | 2461 | if (!mem_cgroup_is_root(memcg)) { |
e7018b8d JW |
2462 | unsigned long bytes = nr_pages * PAGE_SIZE; |
2463 | ||
c0ff4b85 | 2464 | res_counter_uncharge(&memcg->res, bytes); |
a3032a2c | 2465 | if (do_swap_account) |
c0ff4b85 | 2466 | res_counter_uncharge(&memcg->memsw, bytes); |
a3032a2c | 2467 | } |
854ffa8d DN |
2468 | } |
2469 | ||
a3b2d692 KH |
2470 | /* |
2471 | * A helper function to get mem_cgroup from ID. must be called under | |
2472 | * rcu_read_lock(). The caller must check css_is_removed() or some if | |
2473 | * it's concern. (dropping refcnt from swap can be called against removed | |
2474 | * memcg.) | |
2475 | */ | |
2476 | static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) | |
2477 | { | |
2478 | struct cgroup_subsys_state *css; | |
2479 | ||
2480 | /* ID 0 is unused ID */ | |
2481 | if (!id) | |
2482 | return NULL; | |
2483 | css = css_lookup(&mem_cgroup_subsys, id); | |
2484 | if (!css) | |
2485 | return NULL; | |
2486 | return container_of(css, struct mem_cgroup, css); | |
2487 | } | |
2488 | ||
e42d9d5d | 2489 | struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) |
b5a84319 | 2490 | { |
c0ff4b85 | 2491 | struct mem_cgroup *memcg = NULL; |
3c776e64 | 2492 | struct page_cgroup *pc; |
a3b2d692 | 2493 | unsigned short id; |
b5a84319 KH |
2494 | swp_entry_t ent; |
2495 | ||
3c776e64 DN |
2496 | VM_BUG_ON(!PageLocked(page)); |
2497 | ||
3c776e64 | 2498 | pc = lookup_page_cgroup(page); |
c0bd3f63 | 2499 | lock_page_cgroup(pc); |
a3b2d692 | 2500 | if (PageCgroupUsed(pc)) { |
c0ff4b85 R |
2501 | memcg = pc->mem_cgroup; |
2502 | if (memcg && !css_tryget(&memcg->css)) | |
2503 | memcg = NULL; | |
e42d9d5d | 2504 | } else if (PageSwapCache(page)) { |
3c776e64 | 2505 | ent.val = page_private(page); |
a3b2d692 KH |
2506 | id = lookup_swap_cgroup(ent); |
2507 | rcu_read_lock(); | |
c0ff4b85 R |
2508 | memcg = mem_cgroup_lookup(id); |
2509 | if (memcg && !css_tryget(&memcg->css)) | |
2510 | memcg = NULL; | |
a3b2d692 | 2511 | rcu_read_unlock(); |
3c776e64 | 2512 | } |
c0bd3f63 | 2513 | unlock_page_cgroup(pc); |
c0ff4b85 | 2514 | return memcg; |
b5a84319 KH |
2515 | } |
2516 | ||
c0ff4b85 | 2517 | static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, |
5564e88b | 2518 | struct page *page, |
7ec99d62 | 2519 | unsigned int nr_pages, |
ca3e0214 | 2520 | struct page_cgroup *pc, |
7ec99d62 | 2521 | enum charge_type ctype) |
7a81b88c | 2522 | { |
ca3e0214 KH |
2523 | lock_page_cgroup(pc); |
2524 | if (unlikely(PageCgroupUsed(pc))) { | |
2525 | unlock_page_cgroup(pc); | |
c0ff4b85 | 2526 | __mem_cgroup_cancel_charge(memcg, nr_pages); |
ca3e0214 KH |
2527 | return; |
2528 | } | |
2529 | /* | |
2530 | * we don't need page_cgroup_lock about tail pages, becase they are not | |
2531 | * accessed by any other context at this point. | |
2532 | */ | |
c0ff4b85 | 2533 | pc->mem_cgroup = memcg; |
261fb61a KH |
2534 | /* |
2535 | * We access a page_cgroup asynchronously without lock_page_cgroup(). | |
2536 | * Especially when a page_cgroup is taken from a page, pc->mem_cgroup | |
2537 | * is accessed after testing USED bit. To make pc->mem_cgroup visible | |
2538 | * before USED bit, we need memory barrier here. | |
2539 | * See mem_cgroup_add_lru_list(), etc. | |
2540 | */ | |
08e552c6 | 2541 | smp_wmb(); |
4b3bde4c BS |
2542 | switch (ctype) { |
2543 | case MEM_CGROUP_CHARGE_TYPE_CACHE: | |
2544 | case MEM_CGROUP_CHARGE_TYPE_SHMEM: | |
2545 | SetPageCgroupCache(pc); | |
2546 | SetPageCgroupUsed(pc); | |
2547 | break; | |
2548 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
2549 | ClearPageCgroupCache(pc); | |
2550 | SetPageCgroupUsed(pc); | |
2551 | break; | |
2552 | default: | |
2553 | break; | |
2554 | } | |
3be91277 | 2555 | |
c0ff4b85 | 2556 | mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), nr_pages); |
52d4b9ac | 2557 | unlock_page_cgroup(pc); |
430e4863 KH |
2558 | /* |
2559 | * "charge_statistics" updated event counter. Then, check it. | |
2560 | * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree. | |
2561 | * if they exceeds softlimit. | |
2562 | */ | |
c0ff4b85 | 2563 | memcg_check_events(memcg, page); |
7a81b88c | 2564 | } |
66e1707b | 2565 | |
ca3e0214 KH |
2566 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
2567 | ||
2568 | #define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) | (1 << PCG_MOVE_LOCK) |\ | |
2569 | (1 << PCG_ACCT_LRU) | (1 << PCG_MIGRATION)) | |
2570 | /* | |
2571 | * Because tail pages are not marked as "used", set it. We're under | |
2572 | * zone->lru_lock, 'splitting on pmd' and compund_lock. | |
2573 | */ | |
2574 | void mem_cgroup_split_huge_fixup(struct page *head, struct page *tail) | |
2575 | { | |
2576 | struct page_cgroup *head_pc = lookup_page_cgroup(head); | |
2577 | struct page_cgroup *tail_pc = lookup_page_cgroup(tail); | |
2578 | unsigned long flags; | |
2579 | ||
3d37c4a9 KH |
2580 | if (mem_cgroup_disabled()) |
2581 | return; | |
ca3e0214 | 2582 | /* |
ece35ca8 | 2583 | * We have no races with charge/uncharge but will have races with |
ca3e0214 KH |
2584 | * page state accounting. |
2585 | */ | |
2586 | move_lock_page_cgroup(head_pc, &flags); | |
2587 | ||
2588 | tail_pc->mem_cgroup = head_pc->mem_cgroup; | |
2589 | smp_wmb(); /* see __commit_charge() */ | |
ece35ca8 KH |
2590 | if (PageCgroupAcctLRU(head_pc)) { |
2591 | enum lru_list lru; | |
2592 | struct mem_cgroup_per_zone *mz; | |
2593 | ||
2594 | /* | |
2595 | * LRU flags cannot be copied because we need to add tail | |
2596 | *.page to LRU by generic call and our hook will be called. | |
2597 | * We hold lru_lock, then, reduce counter directly. | |
2598 | */ | |
2599 | lru = page_lru(head); | |
97a6c37b | 2600 | mz = page_cgroup_zoneinfo(head_pc->mem_cgroup, head); |
ece35ca8 KH |
2601 | MEM_CGROUP_ZSTAT(mz, lru) -= 1; |
2602 | } | |
ca3e0214 KH |
2603 | tail_pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT; |
2604 | move_unlock_page_cgroup(head_pc, &flags); | |
2605 | } | |
2606 | #endif | |
2607 | ||
f817ed48 | 2608 | /** |
de3638d9 | 2609 | * mem_cgroup_move_account - move account of the page |
5564e88b | 2610 | * @page: the page |
7ec99d62 | 2611 | * @nr_pages: number of regular pages (>1 for huge pages) |
f817ed48 KH |
2612 | * @pc: page_cgroup of the page. |
2613 | * @from: mem_cgroup which the page is moved from. | |
2614 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
854ffa8d | 2615 | * @uncharge: whether we should call uncharge and css_put against @from. |
f817ed48 KH |
2616 | * |
2617 | * The caller must confirm following. | |
08e552c6 | 2618 | * - page is not on LRU (isolate_page() is useful.) |
7ec99d62 | 2619 | * - compound_lock is held when nr_pages > 1 |
f817ed48 | 2620 | * |
854ffa8d | 2621 | * This function doesn't do "charge" nor css_get to new cgroup. It should be |
25985edc | 2622 | * done by a caller(__mem_cgroup_try_charge would be useful). If @uncharge is |
854ffa8d DN |
2623 | * true, this function does "uncharge" from old cgroup, but it doesn't if |
2624 | * @uncharge is false, so a caller should do "uncharge". | |
f817ed48 | 2625 | */ |
7ec99d62 JW |
2626 | static int mem_cgroup_move_account(struct page *page, |
2627 | unsigned int nr_pages, | |
2628 | struct page_cgroup *pc, | |
2629 | struct mem_cgroup *from, | |
2630 | struct mem_cgroup *to, | |
2631 | bool uncharge) | |
f817ed48 | 2632 | { |
de3638d9 JW |
2633 | unsigned long flags; |
2634 | int ret; | |
987eba66 | 2635 | |
f817ed48 | 2636 | VM_BUG_ON(from == to); |
5564e88b | 2637 | VM_BUG_ON(PageLRU(page)); |
de3638d9 JW |
2638 | /* |
2639 | * The page is isolated from LRU. So, collapse function | |
2640 | * will not handle this page. But page splitting can happen. | |
2641 | * Do this check under compound_page_lock(). The caller should | |
2642 | * hold it. | |
2643 | */ | |
2644 | ret = -EBUSY; | |
7ec99d62 | 2645 | if (nr_pages > 1 && !PageTransHuge(page)) |
de3638d9 JW |
2646 | goto out; |
2647 | ||
2648 | lock_page_cgroup(pc); | |
2649 | ||
2650 | ret = -EINVAL; | |
2651 | if (!PageCgroupUsed(pc) || pc->mem_cgroup != from) | |
2652 | goto unlock; | |
2653 | ||
2654 | move_lock_page_cgroup(pc, &flags); | |
f817ed48 | 2655 | |
8725d541 | 2656 | if (PageCgroupFileMapped(pc)) { |
c62b1a3b KH |
2657 | /* Update mapped_file data for mem_cgroup */ |
2658 | preempt_disable(); | |
2659 | __this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2660 | __this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2661 | preempt_enable(); | |
d69b042f | 2662 | } |
987eba66 | 2663 | mem_cgroup_charge_statistics(from, PageCgroupCache(pc), -nr_pages); |
854ffa8d DN |
2664 | if (uncharge) |
2665 | /* This is not "cancel", but cancel_charge does all we need. */ | |
e7018b8d | 2666 | __mem_cgroup_cancel_charge(from, nr_pages); |
d69b042f | 2667 | |
854ffa8d | 2668 | /* caller should have done css_get */ |
08e552c6 | 2669 | pc->mem_cgroup = to; |
987eba66 | 2670 | mem_cgroup_charge_statistics(to, PageCgroupCache(pc), nr_pages); |
88703267 KH |
2671 | /* |
2672 | * We charges against "to" which may not have any tasks. Then, "to" | |
2673 | * can be under rmdir(). But in current implementation, caller of | |
4ffef5fe | 2674 | * this function is just force_empty() and move charge, so it's |
25985edc | 2675 | * guaranteed that "to" is never removed. So, we don't check rmdir |
4ffef5fe | 2676 | * status here. |
88703267 | 2677 | */ |
de3638d9 JW |
2678 | move_unlock_page_cgroup(pc, &flags); |
2679 | ret = 0; | |
2680 | unlock: | |
57f9fd7d | 2681 | unlock_page_cgroup(pc); |
d2265e6f KH |
2682 | /* |
2683 | * check events | |
2684 | */ | |
5564e88b JW |
2685 | memcg_check_events(to, page); |
2686 | memcg_check_events(from, page); | |
de3638d9 | 2687 | out: |
f817ed48 KH |
2688 | return ret; |
2689 | } | |
2690 | ||
2691 | /* | |
2692 | * move charges to its parent. | |
2693 | */ | |
2694 | ||
5564e88b JW |
2695 | static int mem_cgroup_move_parent(struct page *page, |
2696 | struct page_cgroup *pc, | |
f817ed48 KH |
2697 | struct mem_cgroup *child, |
2698 | gfp_t gfp_mask) | |
2699 | { | |
2700 | struct cgroup *cg = child->css.cgroup; | |
2701 | struct cgroup *pcg = cg->parent; | |
2702 | struct mem_cgroup *parent; | |
7ec99d62 | 2703 | unsigned int nr_pages; |
4be4489f | 2704 | unsigned long uninitialized_var(flags); |
f817ed48 KH |
2705 | int ret; |
2706 | ||
2707 | /* Is ROOT ? */ | |
2708 | if (!pcg) | |
2709 | return -EINVAL; | |
2710 | ||
57f9fd7d DN |
2711 | ret = -EBUSY; |
2712 | if (!get_page_unless_zero(page)) | |
2713 | goto out; | |
2714 | if (isolate_lru_page(page)) | |
2715 | goto put; | |
52dbb905 | 2716 | |
7ec99d62 | 2717 | nr_pages = hpage_nr_pages(page); |
08e552c6 | 2718 | |
f817ed48 | 2719 | parent = mem_cgroup_from_cont(pcg); |
7ec99d62 | 2720 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, nr_pages, &parent, false); |
a636b327 | 2721 | if (ret || !parent) |
57f9fd7d | 2722 | goto put_back; |
f817ed48 | 2723 | |
7ec99d62 | 2724 | if (nr_pages > 1) |
987eba66 KH |
2725 | flags = compound_lock_irqsave(page); |
2726 | ||
7ec99d62 | 2727 | ret = mem_cgroup_move_account(page, nr_pages, pc, child, parent, true); |
854ffa8d | 2728 | if (ret) |
7ec99d62 | 2729 | __mem_cgroup_cancel_charge(parent, nr_pages); |
8dba474f | 2730 | |
7ec99d62 | 2731 | if (nr_pages > 1) |
987eba66 | 2732 | compound_unlock_irqrestore(page, flags); |
8dba474f | 2733 | put_back: |
08e552c6 | 2734 | putback_lru_page(page); |
57f9fd7d | 2735 | put: |
40d58138 | 2736 | put_page(page); |
57f9fd7d | 2737 | out: |
f817ed48 KH |
2738 | return ret; |
2739 | } | |
2740 | ||
7a81b88c KH |
2741 | /* |
2742 | * Charge the memory controller for page usage. | |
2743 | * Return | |
2744 | * 0 if the charge was successful | |
2745 | * < 0 if the cgroup is over its limit | |
2746 | */ | |
2747 | static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, | |
73045c47 | 2748 | gfp_t gfp_mask, enum charge_type ctype) |
7a81b88c | 2749 | { |
c0ff4b85 | 2750 | struct mem_cgroup *memcg = NULL; |
7ec99d62 | 2751 | unsigned int nr_pages = 1; |
7a81b88c | 2752 | struct page_cgroup *pc; |
8493ae43 | 2753 | bool oom = true; |
7a81b88c | 2754 | int ret; |
ec168510 | 2755 | |
37c2ac78 | 2756 | if (PageTransHuge(page)) { |
7ec99d62 | 2757 | nr_pages <<= compound_order(page); |
37c2ac78 | 2758 | VM_BUG_ON(!PageTransHuge(page)); |
8493ae43 JW |
2759 | /* |
2760 | * Never OOM-kill a process for a huge page. The | |
2761 | * fault handler will fall back to regular pages. | |
2762 | */ | |
2763 | oom = false; | |
37c2ac78 | 2764 | } |
7a81b88c KH |
2765 | |
2766 | pc = lookup_page_cgroup(page); | |
af4a6621 | 2767 | BUG_ON(!pc); /* XXX: remove this and move pc lookup into commit */ |
7a81b88c | 2768 | |
c0ff4b85 R |
2769 | ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &memcg, oom); |
2770 | if (ret || !memcg) | |
7a81b88c KH |
2771 | return ret; |
2772 | ||
c0ff4b85 | 2773 | __mem_cgroup_commit_charge(memcg, page, nr_pages, pc, ctype); |
8a9f3ccd | 2774 | return 0; |
8a9f3ccd BS |
2775 | } |
2776 | ||
7a81b88c KH |
2777 | int mem_cgroup_newpage_charge(struct page *page, |
2778 | struct mm_struct *mm, gfp_t gfp_mask) | |
217bc319 | 2779 | { |
f8d66542 | 2780 | if (mem_cgroup_disabled()) |
cede86ac | 2781 | return 0; |
69029cd5 KH |
2782 | /* |
2783 | * If already mapped, we don't have to account. | |
2784 | * If page cache, page->mapping has address_space. | |
2785 | * But page->mapping may have out-of-use anon_vma pointer, | |
2786 | * detecit it by PageAnon() check. newly-mapped-anon's page->mapping | |
2787 | * is NULL. | |
2788 | */ | |
2789 | if (page_mapped(page) || (page->mapping && !PageAnon(page))) | |
2790 | return 0; | |
2791 | if (unlikely(!mm)) | |
2792 | mm = &init_mm; | |
217bc319 | 2793 | return mem_cgroup_charge_common(page, mm, gfp_mask, |
73045c47 | 2794 | MEM_CGROUP_CHARGE_TYPE_MAPPED); |
217bc319 KH |
2795 | } |
2796 | ||
83aae4c7 DN |
2797 | static void |
2798 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
2799 | enum charge_type ctype); | |
2800 | ||
5a6475a4 | 2801 | static void |
c0ff4b85 | 2802 | __mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *memcg, |
5a6475a4 KH |
2803 | enum charge_type ctype) |
2804 | { | |
2805 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
2806 | /* | |
2807 | * In some case, SwapCache, FUSE(splice_buf->radixtree), the page | |
2808 | * is already on LRU. It means the page may on some other page_cgroup's | |
2809 | * LRU. Take care of it. | |
2810 | */ | |
2811 | mem_cgroup_lru_del_before_commit(page); | |
c0ff4b85 | 2812 | __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype); |
5a6475a4 KH |
2813 | mem_cgroup_lru_add_after_commit(page); |
2814 | return; | |
2815 | } | |
2816 | ||
e1a1cd59 BS |
2817 | int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, |
2818 | gfp_t gfp_mask) | |
8697d331 | 2819 | { |
c0ff4b85 | 2820 | struct mem_cgroup *memcg = NULL; |
b5a84319 KH |
2821 | int ret; |
2822 | ||
f8d66542 | 2823 | if (mem_cgroup_disabled()) |
cede86ac | 2824 | return 0; |
52d4b9ac KH |
2825 | if (PageCompound(page)) |
2826 | return 0; | |
accf163e | 2827 | |
73045c47 | 2828 | if (unlikely(!mm)) |
8697d331 | 2829 | mm = &init_mm; |
accf163e | 2830 | |
5a6475a4 | 2831 | if (page_is_file_cache(page)) { |
c0ff4b85 R |
2832 | ret = __mem_cgroup_try_charge(mm, gfp_mask, 1, &memcg, true); |
2833 | if (ret || !memcg) | |
5a6475a4 | 2834 | return ret; |
b5a84319 | 2835 | |
5a6475a4 KH |
2836 | /* |
2837 | * FUSE reuses pages without going through the final | |
2838 | * put that would remove them from the LRU list, make | |
2839 | * sure that they get relinked properly. | |
2840 | */ | |
c0ff4b85 | 2841 | __mem_cgroup_commit_charge_lrucare(page, memcg, |
5a6475a4 KH |
2842 | MEM_CGROUP_CHARGE_TYPE_CACHE); |
2843 | return ret; | |
2844 | } | |
83aae4c7 DN |
2845 | /* shmem */ |
2846 | if (PageSwapCache(page)) { | |
c0ff4b85 | 2847 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &memcg); |
83aae4c7 | 2848 | if (!ret) |
c0ff4b85 | 2849 | __mem_cgroup_commit_charge_swapin(page, memcg, |
83aae4c7 DN |
2850 | MEM_CGROUP_CHARGE_TYPE_SHMEM); |
2851 | } else | |
2852 | ret = mem_cgroup_charge_common(page, mm, gfp_mask, | |
73045c47 | 2853 | MEM_CGROUP_CHARGE_TYPE_SHMEM); |
b5a84319 | 2854 | |
b5a84319 | 2855 | return ret; |
e8589cc1 KH |
2856 | } |
2857 | ||
54595fe2 KH |
2858 | /* |
2859 | * While swap-in, try_charge -> commit or cancel, the page is locked. | |
2860 | * And when try_charge() successfully returns, one refcnt to memcg without | |
21ae2956 | 2861 | * struct page_cgroup is acquired. This refcnt will be consumed by |
54595fe2 KH |
2862 | * "commit()" or removed by "cancel()" |
2863 | */ | |
8c7c6e34 KH |
2864 | int mem_cgroup_try_charge_swapin(struct mm_struct *mm, |
2865 | struct page *page, | |
2866 | gfp_t mask, struct mem_cgroup **ptr) | |
2867 | { | |
c0ff4b85 | 2868 | struct mem_cgroup *memcg; |
54595fe2 | 2869 | int ret; |
8c7c6e34 | 2870 | |
56039efa KH |
2871 | *ptr = NULL; |
2872 | ||
f8d66542 | 2873 | if (mem_cgroup_disabled()) |
8c7c6e34 KH |
2874 | return 0; |
2875 | ||
2876 | if (!do_swap_account) | |
2877 | goto charge_cur_mm; | |
8c7c6e34 KH |
2878 | /* |
2879 | * A racing thread's fault, or swapoff, may have already updated | |
407f9c8b HD |
2880 | * the pte, and even removed page from swap cache: in those cases |
2881 | * do_swap_page()'s pte_same() test will fail; but there's also a | |
2882 | * KSM case which does need to charge the page. | |
8c7c6e34 KH |
2883 | */ |
2884 | if (!PageSwapCache(page)) | |
407f9c8b | 2885 | goto charge_cur_mm; |
c0ff4b85 R |
2886 | memcg = try_get_mem_cgroup_from_page(page); |
2887 | if (!memcg) | |
54595fe2 | 2888 | goto charge_cur_mm; |
c0ff4b85 | 2889 | *ptr = memcg; |
7ec99d62 | 2890 | ret = __mem_cgroup_try_charge(NULL, mask, 1, ptr, true); |
c0ff4b85 | 2891 | css_put(&memcg->css); |
54595fe2 | 2892 | return ret; |
8c7c6e34 KH |
2893 | charge_cur_mm: |
2894 | if (unlikely(!mm)) | |
2895 | mm = &init_mm; | |
7ec99d62 | 2896 | return __mem_cgroup_try_charge(mm, mask, 1, ptr, true); |
8c7c6e34 KH |
2897 | } |
2898 | ||
83aae4c7 DN |
2899 | static void |
2900 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
2901 | enum charge_type ctype) | |
7a81b88c | 2902 | { |
f8d66542 | 2903 | if (mem_cgroup_disabled()) |
7a81b88c KH |
2904 | return; |
2905 | if (!ptr) | |
2906 | return; | |
88703267 | 2907 | cgroup_exclude_rmdir(&ptr->css); |
5a6475a4 KH |
2908 | |
2909 | __mem_cgroup_commit_charge_lrucare(page, ptr, ctype); | |
8c7c6e34 KH |
2910 | /* |
2911 | * Now swap is on-memory. This means this page may be | |
2912 | * counted both as mem and swap....double count. | |
03f3c433 KH |
2913 | * Fix it by uncharging from memsw. Basically, this SwapCache is stable |
2914 | * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page() | |
2915 | * may call delete_from_swap_cache() before reach here. | |
8c7c6e34 | 2916 | */ |
03f3c433 | 2917 | if (do_swap_account && PageSwapCache(page)) { |
8c7c6e34 | 2918 | swp_entry_t ent = {.val = page_private(page)}; |
a3b2d692 | 2919 | unsigned short id; |
8c7c6e34 | 2920 | struct mem_cgroup *memcg; |
a3b2d692 KH |
2921 | |
2922 | id = swap_cgroup_record(ent, 0); | |
2923 | rcu_read_lock(); | |
2924 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 2925 | if (memcg) { |
a3b2d692 KH |
2926 | /* |
2927 | * This recorded memcg can be obsolete one. So, avoid | |
2928 | * calling css_tryget | |
2929 | */ | |
0c3e73e8 | 2930 | if (!mem_cgroup_is_root(memcg)) |
4e649152 | 2931 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
0c3e73e8 | 2932 | mem_cgroup_swap_statistics(memcg, false); |
8c7c6e34 KH |
2933 | mem_cgroup_put(memcg); |
2934 | } | |
a3b2d692 | 2935 | rcu_read_unlock(); |
8c7c6e34 | 2936 | } |
88703267 KH |
2937 | /* |
2938 | * At swapin, we may charge account against cgroup which has no tasks. | |
2939 | * So, rmdir()->pre_destroy() can be called while we do this charge. | |
2940 | * In that case, we need to call pre_destroy() again. check it here. | |
2941 | */ | |
2942 | cgroup_release_and_wakeup_rmdir(&ptr->css); | |
7a81b88c KH |
2943 | } |
2944 | ||
83aae4c7 DN |
2945 | void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) |
2946 | { | |
2947 | __mem_cgroup_commit_charge_swapin(page, ptr, | |
2948 | MEM_CGROUP_CHARGE_TYPE_MAPPED); | |
2949 | } | |
2950 | ||
c0ff4b85 | 2951 | void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg) |
7a81b88c | 2952 | { |
f8d66542 | 2953 | if (mem_cgroup_disabled()) |
7a81b88c | 2954 | return; |
c0ff4b85 | 2955 | if (!memcg) |
7a81b88c | 2956 | return; |
c0ff4b85 | 2957 | __mem_cgroup_cancel_charge(memcg, 1); |
7a81b88c KH |
2958 | } |
2959 | ||
c0ff4b85 | 2960 | static void mem_cgroup_do_uncharge(struct mem_cgroup *memcg, |
7ec99d62 JW |
2961 | unsigned int nr_pages, |
2962 | const enum charge_type ctype) | |
569b846d KH |
2963 | { |
2964 | struct memcg_batch_info *batch = NULL; | |
2965 | bool uncharge_memsw = true; | |
7ec99d62 | 2966 | |
569b846d KH |
2967 | /* If swapout, usage of swap doesn't decrease */ |
2968 | if (!do_swap_account || ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) | |
2969 | uncharge_memsw = false; | |
569b846d KH |
2970 | |
2971 | batch = ¤t->memcg_batch; | |
2972 | /* | |
2973 | * In usual, we do css_get() when we remember memcg pointer. | |
2974 | * But in this case, we keep res->usage until end of a series of | |
2975 | * uncharges. Then, it's ok to ignore memcg's refcnt. | |
2976 | */ | |
2977 | if (!batch->memcg) | |
c0ff4b85 | 2978 | batch->memcg = memcg; |
3c11ecf4 KH |
2979 | /* |
2980 | * do_batch > 0 when unmapping pages or inode invalidate/truncate. | |
25985edc | 2981 | * In those cases, all pages freed continuously can be expected to be in |
3c11ecf4 KH |
2982 | * the same cgroup and we have chance to coalesce uncharges. |
2983 | * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE) | |
2984 | * because we want to do uncharge as soon as possible. | |
2985 | */ | |
2986 | ||
2987 | if (!batch->do_batch || test_thread_flag(TIF_MEMDIE)) | |
2988 | goto direct_uncharge; | |
2989 | ||
7ec99d62 | 2990 | if (nr_pages > 1) |
ec168510 AA |
2991 | goto direct_uncharge; |
2992 | ||
569b846d KH |
2993 | /* |
2994 | * In typical case, batch->memcg == mem. This means we can | |
2995 | * merge a series of uncharges to an uncharge of res_counter. | |
2996 | * If not, we uncharge res_counter ony by one. | |
2997 | */ | |
c0ff4b85 | 2998 | if (batch->memcg != memcg) |
569b846d KH |
2999 | goto direct_uncharge; |
3000 | /* remember freed charge and uncharge it later */ | |
7ffd4ca7 | 3001 | batch->nr_pages++; |
569b846d | 3002 | if (uncharge_memsw) |
7ffd4ca7 | 3003 | batch->memsw_nr_pages++; |
569b846d KH |
3004 | return; |
3005 | direct_uncharge: | |
c0ff4b85 | 3006 | res_counter_uncharge(&memcg->res, nr_pages * PAGE_SIZE); |
569b846d | 3007 | if (uncharge_memsw) |
c0ff4b85 R |
3008 | res_counter_uncharge(&memcg->memsw, nr_pages * PAGE_SIZE); |
3009 | if (unlikely(batch->memcg != memcg)) | |
3010 | memcg_oom_recover(memcg); | |
569b846d KH |
3011 | return; |
3012 | } | |
7a81b88c | 3013 | |
8a9f3ccd | 3014 | /* |
69029cd5 | 3015 | * uncharge if !page_mapped(page) |
8a9f3ccd | 3016 | */ |
8c7c6e34 | 3017 | static struct mem_cgroup * |
69029cd5 | 3018 | __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) |
8a9f3ccd | 3019 | { |
c0ff4b85 | 3020 | struct mem_cgroup *memcg = NULL; |
7ec99d62 JW |
3021 | unsigned int nr_pages = 1; |
3022 | struct page_cgroup *pc; | |
8a9f3ccd | 3023 | |
f8d66542 | 3024 | if (mem_cgroup_disabled()) |
8c7c6e34 | 3025 | return NULL; |
4077960e | 3026 | |
d13d1443 | 3027 | if (PageSwapCache(page)) |
8c7c6e34 | 3028 | return NULL; |
d13d1443 | 3029 | |
37c2ac78 | 3030 | if (PageTransHuge(page)) { |
7ec99d62 | 3031 | nr_pages <<= compound_order(page); |
37c2ac78 AA |
3032 | VM_BUG_ON(!PageTransHuge(page)); |
3033 | } | |
8697d331 | 3034 | /* |
3c541e14 | 3035 | * Check if our page_cgroup is valid |
8697d331 | 3036 | */ |
52d4b9ac KH |
3037 | pc = lookup_page_cgroup(page); |
3038 | if (unlikely(!pc || !PageCgroupUsed(pc))) | |
8c7c6e34 | 3039 | return NULL; |
b9c565d5 | 3040 | |
52d4b9ac | 3041 | lock_page_cgroup(pc); |
d13d1443 | 3042 | |
c0ff4b85 | 3043 | memcg = pc->mem_cgroup; |
8c7c6e34 | 3044 | |
d13d1443 KH |
3045 | if (!PageCgroupUsed(pc)) |
3046 | goto unlock_out; | |
3047 | ||
3048 | switch (ctype) { | |
3049 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
8a9478ca | 3050 | case MEM_CGROUP_CHARGE_TYPE_DROP: |
ac39cf8c | 3051 | /* See mem_cgroup_prepare_migration() */ |
3052 | if (page_mapped(page) || PageCgroupMigration(pc)) | |
d13d1443 KH |
3053 | goto unlock_out; |
3054 | break; | |
3055 | case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: | |
3056 | if (!PageAnon(page)) { /* Shared memory */ | |
3057 | if (page->mapping && !page_is_file_cache(page)) | |
3058 | goto unlock_out; | |
3059 | } else if (page_mapped(page)) /* Anon */ | |
3060 | goto unlock_out; | |
3061 | break; | |
3062 | default: | |
3063 | break; | |
52d4b9ac | 3064 | } |
d13d1443 | 3065 | |
c0ff4b85 | 3066 | mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), -nr_pages); |
04046e1a | 3067 | |
52d4b9ac | 3068 | ClearPageCgroupUsed(pc); |
544122e5 KH |
3069 | /* |
3070 | * pc->mem_cgroup is not cleared here. It will be accessed when it's | |
3071 | * freed from LRU. This is safe because uncharged page is expected not | |
3072 | * to be reused (freed soon). Exception is SwapCache, it's handled by | |
3073 | * special functions. | |
3074 | */ | |
b9c565d5 | 3075 | |
52d4b9ac | 3076 | unlock_page_cgroup(pc); |
f75ca962 | 3077 | /* |
c0ff4b85 | 3078 | * even after unlock, we have memcg->res.usage here and this memcg |
f75ca962 KH |
3079 | * will never be freed. |
3080 | */ | |
c0ff4b85 | 3081 | memcg_check_events(memcg, page); |
f75ca962 | 3082 | if (do_swap_account && ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) { |
c0ff4b85 R |
3083 | mem_cgroup_swap_statistics(memcg, true); |
3084 | mem_cgroup_get(memcg); | |
f75ca962 | 3085 | } |
c0ff4b85 R |
3086 | if (!mem_cgroup_is_root(memcg)) |
3087 | mem_cgroup_do_uncharge(memcg, nr_pages, ctype); | |
6d12e2d8 | 3088 | |
c0ff4b85 | 3089 | return memcg; |
d13d1443 KH |
3090 | |
3091 | unlock_out: | |
3092 | unlock_page_cgroup(pc); | |
8c7c6e34 | 3093 | return NULL; |
3c541e14 BS |
3094 | } |
3095 | ||
69029cd5 KH |
3096 | void mem_cgroup_uncharge_page(struct page *page) |
3097 | { | |
52d4b9ac KH |
3098 | /* early check. */ |
3099 | if (page_mapped(page)) | |
3100 | return; | |
3101 | if (page->mapping && !PageAnon(page)) | |
3102 | return; | |
69029cd5 KH |
3103 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED); |
3104 | } | |
3105 | ||
3106 | void mem_cgroup_uncharge_cache_page(struct page *page) | |
3107 | { | |
3108 | VM_BUG_ON(page_mapped(page)); | |
b7abea96 | 3109 | VM_BUG_ON(page->mapping); |
69029cd5 KH |
3110 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); |
3111 | } | |
3112 | ||
569b846d KH |
3113 | /* |
3114 | * Batch_start/batch_end is called in unmap_page_range/invlidate/trucate. | |
3115 | * In that cases, pages are freed continuously and we can expect pages | |
3116 | * are in the same memcg. All these calls itself limits the number of | |
3117 | * pages freed at once, then uncharge_start/end() is called properly. | |
3118 | * This may be called prural(2) times in a context, | |
3119 | */ | |
3120 | ||
3121 | void mem_cgroup_uncharge_start(void) | |
3122 | { | |
3123 | current->memcg_batch.do_batch++; | |
3124 | /* We can do nest. */ | |
3125 | if (current->memcg_batch.do_batch == 1) { | |
3126 | current->memcg_batch.memcg = NULL; | |
7ffd4ca7 JW |
3127 | current->memcg_batch.nr_pages = 0; |
3128 | current->memcg_batch.memsw_nr_pages = 0; | |
569b846d KH |
3129 | } |
3130 | } | |
3131 | ||
3132 | void mem_cgroup_uncharge_end(void) | |
3133 | { | |
3134 | struct memcg_batch_info *batch = ¤t->memcg_batch; | |
3135 | ||
3136 | if (!batch->do_batch) | |
3137 | return; | |
3138 | ||
3139 | batch->do_batch--; | |
3140 | if (batch->do_batch) /* If stacked, do nothing. */ | |
3141 | return; | |
3142 | ||
3143 | if (!batch->memcg) | |
3144 | return; | |
3145 | /* | |
3146 | * This "batch->memcg" is valid without any css_get/put etc... | |
3147 | * bacause we hide charges behind us. | |
3148 | */ | |
7ffd4ca7 JW |
3149 | if (batch->nr_pages) |
3150 | res_counter_uncharge(&batch->memcg->res, | |
3151 | batch->nr_pages * PAGE_SIZE); | |
3152 | if (batch->memsw_nr_pages) | |
3153 | res_counter_uncharge(&batch->memcg->memsw, | |
3154 | batch->memsw_nr_pages * PAGE_SIZE); | |
3c11ecf4 | 3155 | memcg_oom_recover(batch->memcg); |
569b846d KH |
3156 | /* forget this pointer (for sanity check) */ |
3157 | batch->memcg = NULL; | |
3158 | } | |
3159 | ||
e767e056 | 3160 | #ifdef CONFIG_SWAP |
8c7c6e34 | 3161 | /* |
e767e056 | 3162 | * called after __delete_from_swap_cache() and drop "page" account. |
8c7c6e34 KH |
3163 | * memcg information is recorded to swap_cgroup of "ent" |
3164 | */ | |
8a9478ca KH |
3165 | void |
3166 | mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout) | |
8c7c6e34 KH |
3167 | { |
3168 | struct mem_cgroup *memcg; | |
8a9478ca KH |
3169 | int ctype = MEM_CGROUP_CHARGE_TYPE_SWAPOUT; |
3170 | ||
3171 | if (!swapout) /* this was a swap cache but the swap is unused ! */ | |
3172 | ctype = MEM_CGROUP_CHARGE_TYPE_DROP; | |
3173 | ||
3174 | memcg = __mem_cgroup_uncharge_common(page, ctype); | |
8c7c6e34 | 3175 | |
f75ca962 KH |
3176 | /* |
3177 | * record memcg information, if swapout && memcg != NULL, | |
3178 | * mem_cgroup_get() was called in uncharge(). | |
3179 | */ | |
3180 | if (do_swap_account && swapout && memcg) | |
a3b2d692 | 3181 | swap_cgroup_record(ent, css_id(&memcg->css)); |
8c7c6e34 | 3182 | } |
e767e056 | 3183 | #endif |
8c7c6e34 KH |
3184 | |
3185 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
3186 | /* | |
3187 | * called from swap_entry_free(). remove record in swap_cgroup and | |
3188 | * uncharge "memsw" account. | |
3189 | */ | |
3190 | void mem_cgroup_uncharge_swap(swp_entry_t ent) | |
d13d1443 | 3191 | { |
8c7c6e34 | 3192 | struct mem_cgroup *memcg; |
a3b2d692 | 3193 | unsigned short id; |
8c7c6e34 KH |
3194 | |
3195 | if (!do_swap_account) | |
3196 | return; | |
3197 | ||
a3b2d692 KH |
3198 | id = swap_cgroup_record(ent, 0); |
3199 | rcu_read_lock(); | |
3200 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 3201 | if (memcg) { |
a3b2d692 KH |
3202 | /* |
3203 | * We uncharge this because swap is freed. | |
3204 | * This memcg can be obsolete one. We avoid calling css_tryget | |
3205 | */ | |
0c3e73e8 | 3206 | if (!mem_cgroup_is_root(memcg)) |
4e649152 | 3207 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
0c3e73e8 | 3208 | mem_cgroup_swap_statistics(memcg, false); |
8c7c6e34 KH |
3209 | mem_cgroup_put(memcg); |
3210 | } | |
a3b2d692 | 3211 | rcu_read_unlock(); |
d13d1443 | 3212 | } |
02491447 DN |
3213 | |
3214 | /** | |
3215 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
3216 | * @entry: swap entry to be moved | |
3217 | * @from: mem_cgroup which the entry is moved from | |
3218 | * @to: mem_cgroup which the entry is moved to | |
483c30b5 | 3219 | * @need_fixup: whether we should fixup res_counters and refcounts. |
02491447 DN |
3220 | * |
3221 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
3222 | * as the mem_cgroup's id of @from. | |
3223 | * | |
3224 | * Returns 0 on success, -EINVAL on failure. | |
3225 | * | |
3226 | * The caller must have charged to @to, IOW, called res_counter_charge() about | |
3227 | * both res and memsw, and called css_get(). | |
3228 | */ | |
3229 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
483c30b5 | 3230 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
02491447 DN |
3231 | { |
3232 | unsigned short old_id, new_id; | |
3233 | ||
3234 | old_id = css_id(&from->css); | |
3235 | new_id = css_id(&to->css); | |
3236 | ||
3237 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
02491447 | 3238 | mem_cgroup_swap_statistics(from, false); |
483c30b5 | 3239 | mem_cgroup_swap_statistics(to, true); |
02491447 | 3240 | /* |
483c30b5 DN |
3241 | * This function is only called from task migration context now. |
3242 | * It postpones res_counter and refcount handling till the end | |
3243 | * of task migration(mem_cgroup_clear_mc()) for performance | |
3244 | * improvement. But we cannot postpone mem_cgroup_get(to) | |
3245 | * because if the process that has been moved to @to does | |
3246 | * swap-in, the refcount of @to might be decreased to 0. | |
02491447 | 3247 | */ |
02491447 | 3248 | mem_cgroup_get(to); |
483c30b5 DN |
3249 | if (need_fixup) { |
3250 | if (!mem_cgroup_is_root(from)) | |
3251 | res_counter_uncharge(&from->memsw, PAGE_SIZE); | |
3252 | mem_cgroup_put(from); | |
3253 | /* | |
3254 | * we charged both to->res and to->memsw, so we should | |
3255 | * uncharge to->res. | |
3256 | */ | |
3257 | if (!mem_cgroup_is_root(to)) | |
3258 | res_counter_uncharge(&to->res, PAGE_SIZE); | |
483c30b5 | 3259 | } |
02491447 DN |
3260 | return 0; |
3261 | } | |
3262 | return -EINVAL; | |
3263 | } | |
3264 | #else | |
3265 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
483c30b5 | 3266 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
02491447 DN |
3267 | { |
3268 | return -EINVAL; | |
3269 | } | |
8c7c6e34 | 3270 | #endif |
d13d1443 | 3271 | |
ae41be37 | 3272 | /* |
01b1ae63 KH |
3273 | * Before starting migration, account PAGE_SIZE to mem_cgroup that the old |
3274 | * page belongs to. | |
ae41be37 | 3275 | */ |
ac39cf8c | 3276 | int mem_cgroup_prepare_migration(struct page *page, |
ef6a3c63 | 3277 | struct page *newpage, struct mem_cgroup **ptr, gfp_t gfp_mask) |
ae41be37 | 3278 | { |
c0ff4b85 | 3279 | struct mem_cgroup *memcg = NULL; |
7ec99d62 | 3280 | struct page_cgroup *pc; |
ac39cf8c | 3281 | enum charge_type ctype; |
e8589cc1 | 3282 | int ret = 0; |
8869b8f6 | 3283 | |
56039efa KH |
3284 | *ptr = NULL; |
3285 | ||
ec168510 | 3286 | VM_BUG_ON(PageTransHuge(page)); |
f8d66542 | 3287 | if (mem_cgroup_disabled()) |
4077960e BS |
3288 | return 0; |
3289 | ||
52d4b9ac KH |
3290 | pc = lookup_page_cgroup(page); |
3291 | lock_page_cgroup(pc); | |
3292 | if (PageCgroupUsed(pc)) { | |
c0ff4b85 R |
3293 | memcg = pc->mem_cgroup; |
3294 | css_get(&memcg->css); | |
ac39cf8c | 3295 | /* |
3296 | * At migrating an anonymous page, its mapcount goes down | |
3297 | * to 0 and uncharge() will be called. But, even if it's fully | |
3298 | * unmapped, migration may fail and this page has to be | |
3299 | * charged again. We set MIGRATION flag here and delay uncharge | |
3300 | * until end_migration() is called | |
3301 | * | |
3302 | * Corner Case Thinking | |
3303 | * A) | |
3304 | * When the old page was mapped as Anon and it's unmap-and-freed | |
3305 | * while migration was ongoing. | |
3306 | * If unmap finds the old page, uncharge() of it will be delayed | |
3307 | * until end_migration(). If unmap finds a new page, it's | |
3308 | * uncharged when it make mapcount to be 1->0. If unmap code | |
3309 | * finds swap_migration_entry, the new page will not be mapped | |
3310 | * and end_migration() will find it(mapcount==0). | |
3311 | * | |
3312 | * B) | |
3313 | * When the old page was mapped but migraion fails, the kernel | |
3314 | * remaps it. A charge for it is kept by MIGRATION flag even | |
3315 | * if mapcount goes down to 0. We can do remap successfully | |
3316 | * without charging it again. | |
3317 | * | |
3318 | * C) | |
3319 | * The "old" page is under lock_page() until the end of | |
3320 | * migration, so, the old page itself will not be swapped-out. | |
3321 | * If the new page is swapped out before end_migraton, our | |
3322 | * hook to usual swap-out path will catch the event. | |
3323 | */ | |
3324 | if (PageAnon(page)) | |
3325 | SetPageCgroupMigration(pc); | |
e8589cc1 | 3326 | } |
52d4b9ac | 3327 | unlock_page_cgroup(pc); |
ac39cf8c | 3328 | /* |
3329 | * If the page is not charged at this point, | |
3330 | * we return here. | |
3331 | */ | |
c0ff4b85 | 3332 | if (!memcg) |
ac39cf8c | 3333 | return 0; |
01b1ae63 | 3334 | |
c0ff4b85 | 3335 | *ptr = memcg; |
7ec99d62 | 3336 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, 1, ptr, false); |
c0ff4b85 | 3337 | css_put(&memcg->css);/* drop extra refcnt */ |
ac39cf8c | 3338 | if (ret || *ptr == NULL) { |
3339 | if (PageAnon(page)) { | |
3340 | lock_page_cgroup(pc); | |
3341 | ClearPageCgroupMigration(pc); | |
3342 | unlock_page_cgroup(pc); | |
3343 | /* | |
3344 | * The old page may be fully unmapped while we kept it. | |
3345 | */ | |
3346 | mem_cgroup_uncharge_page(page); | |
3347 | } | |
3348 | return -ENOMEM; | |
e8589cc1 | 3349 | } |
ac39cf8c | 3350 | /* |
3351 | * We charge new page before it's used/mapped. So, even if unlock_page() | |
3352 | * is called before end_migration, we can catch all events on this new | |
3353 | * page. In the case new page is migrated but not remapped, new page's | |
3354 | * mapcount will be finally 0 and we call uncharge in end_migration(). | |
3355 | */ | |
3356 | pc = lookup_page_cgroup(newpage); | |
3357 | if (PageAnon(page)) | |
3358 | ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED; | |
3359 | else if (page_is_file_cache(page)) | |
3360 | ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; | |
3361 | else | |
3362 | ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; | |
c0ff4b85 | 3363 | __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype); |
e8589cc1 | 3364 | return ret; |
ae41be37 | 3365 | } |
8869b8f6 | 3366 | |
69029cd5 | 3367 | /* remove redundant charge if migration failed*/ |
c0ff4b85 | 3368 | void mem_cgroup_end_migration(struct mem_cgroup *memcg, |
50de1dd9 | 3369 | struct page *oldpage, struct page *newpage, bool migration_ok) |
ae41be37 | 3370 | { |
ac39cf8c | 3371 | struct page *used, *unused; |
01b1ae63 | 3372 | struct page_cgroup *pc; |
01b1ae63 | 3373 | |
c0ff4b85 | 3374 | if (!memcg) |
01b1ae63 | 3375 | return; |
ac39cf8c | 3376 | /* blocks rmdir() */ |
c0ff4b85 | 3377 | cgroup_exclude_rmdir(&memcg->css); |
50de1dd9 | 3378 | if (!migration_ok) { |
ac39cf8c | 3379 | used = oldpage; |
3380 | unused = newpage; | |
01b1ae63 | 3381 | } else { |
ac39cf8c | 3382 | used = newpage; |
01b1ae63 KH |
3383 | unused = oldpage; |
3384 | } | |
69029cd5 | 3385 | /* |
ac39cf8c | 3386 | * We disallowed uncharge of pages under migration because mapcount |
3387 | * of the page goes down to zero, temporarly. | |
3388 | * Clear the flag and check the page should be charged. | |
01b1ae63 | 3389 | */ |
ac39cf8c | 3390 | pc = lookup_page_cgroup(oldpage); |
3391 | lock_page_cgroup(pc); | |
3392 | ClearPageCgroupMigration(pc); | |
3393 | unlock_page_cgroup(pc); | |
01b1ae63 | 3394 | |
ac39cf8c | 3395 | __mem_cgroup_uncharge_common(unused, MEM_CGROUP_CHARGE_TYPE_FORCE); |
3396 | ||
01b1ae63 | 3397 | /* |
ac39cf8c | 3398 | * If a page is a file cache, radix-tree replacement is very atomic |
3399 | * and we can skip this check. When it was an Anon page, its mapcount | |
3400 | * goes down to 0. But because we added MIGRATION flage, it's not | |
3401 | * uncharged yet. There are several case but page->mapcount check | |
3402 | * and USED bit check in mem_cgroup_uncharge_page() will do enough | |
3403 | * check. (see prepare_charge() also) | |
69029cd5 | 3404 | */ |
ac39cf8c | 3405 | if (PageAnon(used)) |
3406 | mem_cgroup_uncharge_page(used); | |
88703267 | 3407 | /* |
ac39cf8c | 3408 | * At migration, we may charge account against cgroup which has no |
3409 | * tasks. | |
88703267 KH |
3410 | * So, rmdir()->pre_destroy() can be called while we do this charge. |
3411 | * In that case, we need to call pre_destroy() again. check it here. | |
3412 | */ | |
c0ff4b85 | 3413 | cgroup_release_and_wakeup_rmdir(&memcg->css); |
ae41be37 | 3414 | } |
78fb7466 | 3415 | |
ab936cbc KH |
3416 | /* |
3417 | * At replace page cache, newpage is not under any memcg but it's on | |
3418 | * LRU. So, this function doesn't touch res_counter but handles LRU | |
3419 | * in correct way. Both pages are locked so we cannot race with uncharge. | |
3420 | */ | |
3421 | void mem_cgroup_replace_page_cache(struct page *oldpage, | |
3422 | struct page *newpage) | |
3423 | { | |
3424 | struct mem_cgroup *memcg; | |
3425 | struct page_cgroup *pc; | |
3426 | struct zone *zone; | |
3427 | enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE; | |
3428 | unsigned long flags; | |
3429 | ||
3430 | if (mem_cgroup_disabled()) | |
3431 | return; | |
3432 | ||
3433 | pc = lookup_page_cgroup(oldpage); | |
3434 | /* fix accounting on old pages */ | |
3435 | lock_page_cgroup(pc); | |
3436 | memcg = pc->mem_cgroup; | |
3437 | mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), -1); | |
3438 | ClearPageCgroupUsed(pc); | |
3439 | unlock_page_cgroup(pc); | |
3440 | ||
3441 | if (PageSwapBacked(oldpage)) | |
3442 | type = MEM_CGROUP_CHARGE_TYPE_SHMEM; | |
3443 | ||
3444 | zone = page_zone(newpage); | |
3445 | pc = lookup_page_cgroup(newpage); | |
3446 | /* | |
3447 | * Even if newpage->mapping was NULL before starting replacement, | |
3448 | * the newpage may be on LRU(or pagevec for LRU) already. We lock | |
3449 | * LRU while we overwrite pc->mem_cgroup. | |
3450 | */ | |
3451 | spin_lock_irqsave(&zone->lru_lock, flags); | |
3452 | if (PageLRU(newpage)) | |
3453 | del_page_from_lru_list(zone, newpage, page_lru(newpage)); | |
3454 | __mem_cgroup_commit_charge(memcg, newpage, 1, pc, type); | |
3455 | if (PageLRU(newpage)) | |
3456 | add_page_to_lru_list(zone, newpage, page_lru(newpage)); | |
3457 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
3458 | } | |
3459 | ||
f212ad7c DN |
3460 | #ifdef CONFIG_DEBUG_VM |
3461 | static struct page_cgroup *lookup_page_cgroup_used(struct page *page) | |
3462 | { | |
3463 | struct page_cgroup *pc; | |
3464 | ||
3465 | pc = lookup_page_cgroup(page); | |
3466 | if (likely(pc) && PageCgroupUsed(pc)) | |
3467 | return pc; | |
3468 | return NULL; | |
3469 | } | |
3470 | ||
3471 | bool mem_cgroup_bad_page_check(struct page *page) | |
3472 | { | |
3473 | if (mem_cgroup_disabled()) | |
3474 | return false; | |
3475 | ||
3476 | return lookup_page_cgroup_used(page) != NULL; | |
3477 | } | |
3478 | ||
3479 | void mem_cgroup_print_bad_page(struct page *page) | |
3480 | { | |
3481 | struct page_cgroup *pc; | |
3482 | ||
3483 | pc = lookup_page_cgroup_used(page); | |
3484 | if (pc) { | |
3485 | int ret = -1; | |
3486 | char *path; | |
3487 | ||
3488 | printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p", | |
3489 | pc, pc->flags, pc->mem_cgroup); | |
3490 | ||
3491 | path = kmalloc(PATH_MAX, GFP_KERNEL); | |
3492 | if (path) { | |
3493 | rcu_read_lock(); | |
3494 | ret = cgroup_path(pc->mem_cgroup->css.cgroup, | |
3495 | path, PATH_MAX); | |
3496 | rcu_read_unlock(); | |
3497 | } | |
3498 | ||
3499 | printk(KERN_CONT "(%s)\n", | |
3500 | (ret < 0) ? "cannot get the path" : path); | |
3501 | kfree(path); | |
3502 | } | |
3503 | } | |
3504 | #endif | |
3505 | ||
8c7c6e34 KH |
3506 | static DEFINE_MUTEX(set_limit_mutex); |
3507 | ||
d38d2a75 | 3508 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
8c7c6e34 | 3509 | unsigned long long val) |
628f4235 | 3510 | { |
81d39c20 | 3511 | int retry_count; |
3c11ecf4 | 3512 | u64 memswlimit, memlimit; |
628f4235 | 3513 | int ret = 0; |
81d39c20 KH |
3514 | int children = mem_cgroup_count_children(memcg); |
3515 | u64 curusage, oldusage; | |
3c11ecf4 | 3516 | int enlarge; |
81d39c20 KH |
3517 | |
3518 | /* | |
3519 | * For keeping hierarchical_reclaim simple, how long we should retry | |
3520 | * is depends on callers. We set our retry-count to be function | |
3521 | * of # of children which we should visit in this loop. | |
3522 | */ | |
3523 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; | |
3524 | ||
3525 | oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); | |
628f4235 | 3526 | |
3c11ecf4 | 3527 | enlarge = 0; |
8c7c6e34 | 3528 | while (retry_count) { |
628f4235 KH |
3529 | if (signal_pending(current)) { |
3530 | ret = -EINTR; | |
3531 | break; | |
3532 | } | |
8c7c6e34 KH |
3533 | /* |
3534 | * Rather than hide all in some function, I do this in | |
3535 | * open coded manner. You see what this really does. | |
c0ff4b85 | 3536 | * We have to guarantee memcg->res.limit < memcg->memsw.limit. |
8c7c6e34 KH |
3537 | */ |
3538 | mutex_lock(&set_limit_mutex); | |
3539 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
3540 | if (memswlimit < val) { | |
3541 | ret = -EINVAL; | |
3542 | mutex_unlock(&set_limit_mutex); | |
628f4235 KH |
3543 | break; |
3544 | } | |
3c11ecf4 KH |
3545 | |
3546 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3547 | if (memlimit < val) | |
3548 | enlarge = 1; | |
3549 | ||
8c7c6e34 | 3550 | ret = res_counter_set_limit(&memcg->res, val); |
22a668d7 KH |
3551 | if (!ret) { |
3552 | if (memswlimit == val) | |
3553 | memcg->memsw_is_minimum = true; | |
3554 | else | |
3555 | memcg->memsw_is_minimum = false; | |
3556 | } | |
8c7c6e34 KH |
3557 | mutex_unlock(&set_limit_mutex); |
3558 | ||
3559 | if (!ret) | |
3560 | break; | |
3561 | ||
aa20d489 | 3562 | mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, |
0ae5e89c YH |
3563 | MEM_CGROUP_RECLAIM_SHRINK, |
3564 | NULL); | |
81d39c20 KH |
3565 | curusage = res_counter_read_u64(&memcg->res, RES_USAGE); |
3566 | /* Usage is reduced ? */ | |
3567 | if (curusage >= oldusage) | |
3568 | retry_count--; | |
3569 | else | |
3570 | oldusage = curusage; | |
8c7c6e34 | 3571 | } |
3c11ecf4 KH |
3572 | if (!ret && enlarge) |
3573 | memcg_oom_recover(memcg); | |
14797e23 | 3574 | |
8c7c6e34 KH |
3575 | return ret; |
3576 | } | |
3577 | ||
338c8431 LZ |
3578 | static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, |
3579 | unsigned long long val) | |
8c7c6e34 | 3580 | { |
81d39c20 | 3581 | int retry_count; |
3c11ecf4 | 3582 | u64 memlimit, memswlimit, oldusage, curusage; |
81d39c20 KH |
3583 | int children = mem_cgroup_count_children(memcg); |
3584 | int ret = -EBUSY; | |
3c11ecf4 | 3585 | int enlarge = 0; |
8c7c6e34 | 3586 | |
81d39c20 KH |
3587 | /* see mem_cgroup_resize_res_limit */ |
3588 | retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; | |
3589 | oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); | |
8c7c6e34 KH |
3590 | while (retry_count) { |
3591 | if (signal_pending(current)) { | |
3592 | ret = -EINTR; | |
3593 | break; | |
3594 | } | |
3595 | /* | |
3596 | * Rather than hide all in some function, I do this in | |
3597 | * open coded manner. You see what this really does. | |
c0ff4b85 | 3598 | * We have to guarantee memcg->res.limit < memcg->memsw.limit. |
8c7c6e34 KH |
3599 | */ |
3600 | mutex_lock(&set_limit_mutex); | |
3601 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3602 | if (memlimit > val) { | |
3603 | ret = -EINVAL; | |
3604 | mutex_unlock(&set_limit_mutex); | |
3605 | break; | |
3606 | } | |
3c11ecf4 KH |
3607 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
3608 | if (memswlimit < val) | |
3609 | enlarge = 1; | |
8c7c6e34 | 3610 | ret = res_counter_set_limit(&memcg->memsw, val); |
22a668d7 KH |
3611 | if (!ret) { |
3612 | if (memlimit == val) | |
3613 | memcg->memsw_is_minimum = true; | |
3614 | else | |
3615 | memcg->memsw_is_minimum = false; | |
3616 | } | |
8c7c6e34 KH |
3617 | mutex_unlock(&set_limit_mutex); |
3618 | ||
3619 | if (!ret) | |
3620 | break; | |
3621 | ||
4e416953 | 3622 | mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, |
75822b44 | 3623 | MEM_CGROUP_RECLAIM_NOSWAP | |
0ae5e89c YH |
3624 | MEM_CGROUP_RECLAIM_SHRINK, |
3625 | NULL); | |
8c7c6e34 | 3626 | curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); |
81d39c20 | 3627 | /* Usage is reduced ? */ |
8c7c6e34 | 3628 | if (curusage >= oldusage) |
628f4235 | 3629 | retry_count--; |
81d39c20 KH |
3630 | else |
3631 | oldusage = curusage; | |
628f4235 | 3632 | } |
3c11ecf4 KH |
3633 | if (!ret && enlarge) |
3634 | memcg_oom_recover(memcg); | |
628f4235 KH |
3635 | return ret; |
3636 | } | |
3637 | ||
4e416953 | 3638 | unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, |
0ae5e89c YH |
3639 | gfp_t gfp_mask, |
3640 | unsigned long *total_scanned) | |
4e416953 BS |
3641 | { |
3642 | unsigned long nr_reclaimed = 0; | |
3643 | struct mem_cgroup_per_zone *mz, *next_mz = NULL; | |
3644 | unsigned long reclaimed; | |
3645 | int loop = 0; | |
3646 | struct mem_cgroup_tree_per_zone *mctz; | |
ef8745c1 | 3647 | unsigned long long excess; |
0ae5e89c | 3648 | unsigned long nr_scanned; |
4e416953 BS |
3649 | |
3650 | if (order > 0) | |
3651 | return 0; | |
3652 | ||
00918b6a | 3653 | mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone)); |
4e416953 BS |
3654 | /* |
3655 | * This loop can run a while, specially if mem_cgroup's continuously | |
3656 | * keep exceeding their soft limit and putting the system under | |
3657 | * pressure | |
3658 | */ | |
3659 | do { | |
3660 | if (next_mz) | |
3661 | mz = next_mz; | |
3662 | else | |
3663 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
3664 | if (!mz) | |
3665 | break; | |
3666 | ||
0ae5e89c | 3667 | nr_scanned = 0; |
4e416953 BS |
3668 | reclaimed = mem_cgroup_hierarchical_reclaim(mz->mem, zone, |
3669 | gfp_mask, | |
0ae5e89c YH |
3670 | MEM_CGROUP_RECLAIM_SOFT, |
3671 | &nr_scanned); | |
4e416953 | 3672 | nr_reclaimed += reclaimed; |
0ae5e89c | 3673 | *total_scanned += nr_scanned; |
4e416953 BS |
3674 | spin_lock(&mctz->lock); |
3675 | ||
3676 | /* | |
3677 | * If we failed to reclaim anything from this memory cgroup | |
3678 | * it is time to move on to the next cgroup | |
3679 | */ | |
3680 | next_mz = NULL; | |
3681 | if (!reclaimed) { | |
3682 | do { | |
3683 | /* | |
3684 | * Loop until we find yet another one. | |
3685 | * | |
3686 | * By the time we get the soft_limit lock | |
3687 | * again, someone might have aded the | |
3688 | * group back on the RB tree. Iterate to | |
3689 | * make sure we get a different mem. | |
3690 | * mem_cgroup_largest_soft_limit_node returns | |
3691 | * NULL if no other cgroup is present on | |
3692 | * the tree | |
3693 | */ | |
3694 | next_mz = | |
3695 | __mem_cgroup_largest_soft_limit_node(mctz); | |
39cc98f1 | 3696 | if (next_mz == mz) |
4e416953 | 3697 | css_put(&next_mz->mem->css); |
39cc98f1 | 3698 | else /* next_mz == NULL or other memcg */ |
4e416953 BS |
3699 | break; |
3700 | } while (1); | |
3701 | } | |
4e416953 | 3702 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); |
ef8745c1 | 3703 | excess = res_counter_soft_limit_excess(&mz->mem->res); |
4e416953 BS |
3704 | /* |
3705 | * One school of thought says that we should not add | |
3706 | * back the node to the tree if reclaim returns 0. | |
3707 | * But our reclaim could return 0, simply because due | |
3708 | * to priority we are exposing a smaller subset of | |
3709 | * memory to reclaim from. Consider this as a longer | |
3710 | * term TODO. | |
3711 | */ | |
ef8745c1 KH |
3712 | /* If excess == 0, no tree ops */ |
3713 | __mem_cgroup_insert_exceeded(mz->mem, mz, mctz, excess); | |
4e416953 BS |
3714 | spin_unlock(&mctz->lock); |
3715 | css_put(&mz->mem->css); | |
3716 | loop++; | |
3717 | /* | |
3718 | * Could not reclaim anything and there are no more | |
3719 | * mem cgroups to try or we seem to be looping without | |
3720 | * reclaiming anything. | |
3721 | */ | |
3722 | if (!nr_reclaimed && | |
3723 | (next_mz == NULL || | |
3724 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
3725 | break; | |
3726 | } while (!nr_reclaimed); | |
3727 | if (next_mz) | |
3728 | css_put(&next_mz->mem->css); | |
3729 | return nr_reclaimed; | |
3730 | } | |
3731 | ||
cc847582 KH |
3732 | /* |
3733 | * This routine traverse page_cgroup in given list and drop them all. | |
cc847582 KH |
3734 | * *And* this routine doesn't reclaim page itself, just removes page_cgroup. |
3735 | */ | |
c0ff4b85 | 3736 | static int mem_cgroup_force_empty_list(struct mem_cgroup *memcg, |
08e552c6 | 3737 | int node, int zid, enum lru_list lru) |
cc847582 | 3738 | { |
08e552c6 KH |
3739 | struct zone *zone; |
3740 | struct mem_cgroup_per_zone *mz; | |
f817ed48 | 3741 | struct page_cgroup *pc, *busy; |
08e552c6 | 3742 | unsigned long flags, loop; |
072c56c1 | 3743 | struct list_head *list; |
f817ed48 | 3744 | int ret = 0; |
072c56c1 | 3745 | |
08e552c6 | 3746 | zone = &NODE_DATA(node)->node_zones[zid]; |
c0ff4b85 | 3747 | mz = mem_cgroup_zoneinfo(memcg, node, zid); |
b69408e8 | 3748 | list = &mz->lists[lru]; |
cc847582 | 3749 | |
f817ed48 KH |
3750 | loop = MEM_CGROUP_ZSTAT(mz, lru); |
3751 | /* give some margin against EBUSY etc...*/ | |
3752 | loop += 256; | |
3753 | busy = NULL; | |
3754 | while (loop--) { | |
5564e88b JW |
3755 | struct page *page; |
3756 | ||
f817ed48 | 3757 | ret = 0; |
08e552c6 | 3758 | spin_lock_irqsave(&zone->lru_lock, flags); |
f817ed48 | 3759 | if (list_empty(list)) { |
08e552c6 | 3760 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
52d4b9ac | 3761 | break; |
f817ed48 KH |
3762 | } |
3763 | pc = list_entry(list->prev, struct page_cgroup, lru); | |
3764 | if (busy == pc) { | |
3765 | list_move(&pc->lru, list); | |
648bcc77 | 3766 | busy = NULL; |
08e552c6 | 3767 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 KH |
3768 | continue; |
3769 | } | |
08e552c6 | 3770 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 | 3771 | |
6b3ae58e | 3772 | page = lookup_cgroup_page(pc); |
5564e88b | 3773 | |
c0ff4b85 | 3774 | ret = mem_cgroup_move_parent(page, pc, memcg, GFP_KERNEL); |
f817ed48 | 3775 | if (ret == -ENOMEM) |
52d4b9ac | 3776 | break; |
f817ed48 KH |
3777 | |
3778 | if (ret == -EBUSY || ret == -EINVAL) { | |
3779 | /* found lock contention or "pc" is obsolete. */ | |
3780 | busy = pc; | |
3781 | cond_resched(); | |
3782 | } else | |
3783 | busy = NULL; | |
cc847582 | 3784 | } |
08e552c6 | 3785 | |
f817ed48 KH |
3786 | if (!ret && !list_empty(list)) |
3787 | return -EBUSY; | |
3788 | return ret; | |
cc847582 KH |
3789 | } |
3790 | ||
3791 | /* | |
3792 | * make mem_cgroup's charge to be 0 if there is no task. | |
3793 | * This enables deleting this mem_cgroup. | |
3794 | */ | |
c0ff4b85 | 3795 | static int mem_cgroup_force_empty(struct mem_cgroup *memcg, bool free_all) |
cc847582 | 3796 | { |
f817ed48 KH |
3797 | int ret; |
3798 | int node, zid, shrink; | |
3799 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
c0ff4b85 | 3800 | struct cgroup *cgrp = memcg->css.cgroup; |
8869b8f6 | 3801 | |
c0ff4b85 | 3802 | css_get(&memcg->css); |
f817ed48 KH |
3803 | |
3804 | shrink = 0; | |
c1e862c1 KH |
3805 | /* should free all ? */ |
3806 | if (free_all) | |
3807 | goto try_to_free; | |
f817ed48 | 3808 | move_account: |
fce66477 | 3809 | do { |
f817ed48 | 3810 | ret = -EBUSY; |
c1e862c1 KH |
3811 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children)) |
3812 | goto out; | |
3813 | ret = -EINTR; | |
3814 | if (signal_pending(current)) | |
cc847582 | 3815 | goto out; |
52d4b9ac KH |
3816 | /* This is for making all *used* pages to be on LRU. */ |
3817 | lru_add_drain_all(); | |
c0ff4b85 | 3818 | drain_all_stock_sync(memcg); |
f817ed48 | 3819 | ret = 0; |
c0ff4b85 | 3820 | mem_cgroup_start_move(memcg); |
299b4eaa | 3821 | for_each_node_state(node, N_HIGH_MEMORY) { |
f817ed48 | 3822 | for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { |
b69408e8 | 3823 | enum lru_list l; |
f817ed48 | 3824 | for_each_lru(l) { |
c0ff4b85 | 3825 | ret = mem_cgroup_force_empty_list(memcg, |
08e552c6 | 3826 | node, zid, l); |
f817ed48 KH |
3827 | if (ret) |
3828 | break; | |
3829 | } | |
1ecaab2b | 3830 | } |
f817ed48 KH |
3831 | if (ret) |
3832 | break; | |
3833 | } | |
c0ff4b85 R |
3834 | mem_cgroup_end_move(memcg); |
3835 | memcg_oom_recover(memcg); | |
f817ed48 KH |
3836 | /* it seems parent cgroup doesn't have enough mem */ |
3837 | if (ret == -ENOMEM) | |
3838 | goto try_to_free; | |
52d4b9ac | 3839 | cond_resched(); |
fce66477 | 3840 | /* "ret" should also be checked to ensure all lists are empty. */ |
c0ff4b85 | 3841 | } while (memcg->res.usage > 0 || ret); |
cc847582 | 3842 | out: |
c0ff4b85 | 3843 | css_put(&memcg->css); |
cc847582 | 3844 | return ret; |
f817ed48 KH |
3845 | |
3846 | try_to_free: | |
c1e862c1 KH |
3847 | /* returns EBUSY if there is a task or if we come here twice. */ |
3848 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) { | |
f817ed48 KH |
3849 | ret = -EBUSY; |
3850 | goto out; | |
3851 | } | |
c1e862c1 KH |
3852 | /* we call try-to-free pages for make this cgroup empty */ |
3853 | lru_add_drain_all(); | |
f817ed48 KH |
3854 | /* try to free all pages in this cgroup */ |
3855 | shrink = 1; | |
c0ff4b85 | 3856 | while (nr_retries && memcg->res.usage > 0) { |
f817ed48 | 3857 | int progress; |
c1e862c1 KH |
3858 | |
3859 | if (signal_pending(current)) { | |
3860 | ret = -EINTR; | |
3861 | goto out; | |
3862 | } | |
c0ff4b85 | 3863 | progress = try_to_free_mem_cgroup_pages(memcg, GFP_KERNEL, |
185efc0f | 3864 | false); |
c1e862c1 | 3865 | if (!progress) { |
f817ed48 | 3866 | nr_retries--; |
c1e862c1 | 3867 | /* maybe some writeback is necessary */ |
8aa7e847 | 3868 | congestion_wait(BLK_RW_ASYNC, HZ/10); |
c1e862c1 | 3869 | } |
f817ed48 KH |
3870 | |
3871 | } | |
08e552c6 | 3872 | lru_add_drain(); |
f817ed48 | 3873 | /* try move_account...there may be some *locked* pages. */ |
fce66477 | 3874 | goto move_account; |
cc847582 KH |
3875 | } |
3876 | ||
c1e862c1 KH |
3877 | int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event) |
3878 | { | |
3879 | return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true); | |
3880 | } | |
3881 | ||
3882 | ||
18f59ea7 BS |
3883 | static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft) |
3884 | { | |
3885 | return mem_cgroup_from_cont(cont)->use_hierarchy; | |
3886 | } | |
3887 | ||
3888 | static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft, | |
3889 | u64 val) | |
3890 | { | |
3891 | int retval = 0; | |
c0ff4b85 | 3892 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
18f59ea7 | 3893 | struct cgroup *parent = cont->parent; |
c0ff4b85 | 3894 | struct mem_cgroup *parent_memcg = NULL; |
18f59ea7 BS |
3895 | |
3896 | if (parent) | |
c0ff4b85 | 3897 | parent_memcg = mem_cgroup_from_cont(parent); |
18f59ea7 BS |
3898 | |
3899 | cgroup_lock(); | |
3900 | /* | |
af901ca1 | 3901 | * If parent's use_hierarchy is set, we can't make any modifications |
18f59ea7 BS |
3902 | * in the child subtrees. If it is unset, then the change can |
3903 | * occur, provided the current cgroup has no children. | |
3904 | * | |
3905 | * For the root cgroup, parent_mem is NULL, we allow value to be | |
3906 | * set if there are no children. | |
3907 | */ | |
c0ff4b85 | 3908 | if ((!parent_memcg || !parent_memcg->use_hierarchy) && |
18f59ea7 BS |
3909 | (val == 1 || val == 0)) { |
3910 | if (list_empty(&cont->children)) | |
c0ff4b85 | 3911 | memcg->use_hierarchy = val; |
18f59ea7 BS |
3912 | else |
3913 | retval = -EBUSY; | |
3914 | } else | |
3915 | retval = -EINVAL; | |
3916 | cgroup_unlock(); | |
3917 | ||
3918 | return retval; | |
3919 | } | |
3920 | ||
0c3e73e8 | 3921 | |
c0ff4b85 | 3922 | static unsigned long mem_cgroup_recursive_stat(struct mem_cgroup *memcg, |
7a159cc9 | 3923 | enum mem_cgroup_stat_index idx) |
0c3e73e8 | 3924 | { |
7d74b06f | 3925 | struct mem_cgroup *iter; |
7a159cc9 | 3926 | long val = 0; |
0c3e73e8 | 3927 | |
7a159cc9 | 3928 | /* Per-cpu values can be negative, use a signed accumulator */ |
c0ff4b85 | 3929 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f KH |
3930 | val += mem_cgroup_read_stat(iter, idx); |
3931 | ||
3932 | if (val < 0) /* race ? */ | |
3933 | val = 0; | |
3934 | return val; | |
0c3e73e8 BS |
3935 | } |
3936 | ||
c0ff4b85 | 3937 | static inline u64 mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) |
104f3928 | 3938 | { |
7d74b06f | 3939 | u64 val; |
104f3928 | 3940 | |
c0ff4b85 | 3941 | if (!mem_cgroup_is_root(memcg)) { |
104f3928 | 3942 | if (!swap) |
65c64ce8 | 3943 | return res_counter_read_u64(&memcg->res, RES_USAGE); |
104f3928 | 3944 | else |
65c64ce8 | 3945 | return res_counter_read_u64(&memcg->memsw, RES_USAGE); |
104f3928 KS |
3946 | } |
3947 | ||
c0ff4b85 R |
3948 | val = mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_CACHE); |
3949 | val += mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_RSS); | |
104f3928 | 3950 | |
7d74b06f | 3951 | if (swap) |
c0ff4b85 | 3952 | val += mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_SWAPOUT); |
104f3928 KS |
3953 | |
3954 | return val << PAGE_SHIFT; | |
3955 | } | |
3956 | ||
2c3daa72 | 3957 | static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) |
8cdea7c0 | 3958 | { |
c0ff4b85 | 3959 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
104f3928 | 3960 | u64 val; |
8c7c6e34 KH |
3961 | int type, name; |
3962 | ||
3963 | type = MEMFILE_TYPE(cft->private); | |
3964 | name = MEMFILE_ATTR(cft->private); | |
3965 | switch (type) { | |
3966 | case _MEM: | |
104f3928 | 3967 | if (name == RES_USAGE) |
c0ff4b85 | 3968 | val = mem_cgroup_usage(memcg, false); |
104f3928 | 3969 | else |
c0ff4b85 | 3970 | val = res_counter_read_u64(&memcg->res, name); |
8c7c6e34 KH |
3971 | break; |
3972 | case _MEMSWAP: | |
104f3928 | 3973 | if (name == RES_USAGE) |
c0ff4b85 | 3974 | val = mem_cgroup_usage(memcg, true); |
104f3928 | 3975 | else |
c0ff4b85 | 3976 | val = res_counter_read_u64(&memcg->memsw, name); |
8c7c6e34 KH |
3977 | break; |
3978 | default: | |
3979 | BUG(); | |
3980 | break; | |
3981 | } | |
3982 | return val; | |
8cdea7c0 | 3983 | } |
628f4235 KH |
3984 | /* |
3985 | * The user of this function is... | |
3986 | * RES_LIMIT. | |
3987 | */ | |
856c13aa PM |
3988 | static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, |
3989 | const char *buffer) | |
8cdea7c0 | 3990 | { |
628f4235 | 3991 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
8c7c6e34 | 3992 | int type, name; |
628f4235 KH |
3993 | unsigned long long val; |
3994 | int ret; | |
3995 | ||
8c7c6e34 KH |
3996 | type = MEMFILE_TYPE(cft->private); |
3997 | name = MEMFILE_ATTR(cft->private); | |
3998 | switch (name) { | |
628f4235 | 3999 | case RES_LIMIT: |
4b3bde4c BS |
4000 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
4001 | ret = -EINVAL; | |
4002 | break; | |
4003 | } | |
628f4235 KH |
4004 | /* This function does all necessary parse...reuse it */ |
4005 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
8c7c6e34 KH |
4006 | if (ret) |
4007 | break; | |
4008 | if (type == _MEM) | |
628f4235 | 4009 | ret = mem_cgroup_resize_limit(memcg, val); |
8c7c6e34 KH |
4010 | else |
4011 | ret = mem_cgroup_resize_memsw_limit(memcg, val); | |
628f4235 | 4012 | break; |
296c81d8 BS |
4013 | case RES_SOFT_LIMIT: |
4014 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
4015 | if (ret) | |
4016 | break; | |
4017 | /* | |
4018 | * For memsw, soft limits are hard to implement in terms | |
4019 | * of semantics, for now, we support soft limits for | |
4020 | * control without swap | |
4021 | */ | |
4022 | if (type == _MEM) | |
4023 | ret = res_counter_set_soft_limit(&memcg->res, val); | |
4024 | else | |
4025 | ret = -EINVAL; | |
4026 | break; | |
628f4235 KH |
4027 | default: |
4028 | ret = -EINVAL; /* should be BUG() ? */ | |
4029 | break; | |
4030 | } | |
4031 | return ret; | |
8cdea7c0 BS |
4032 | } |
4033 | ||
fee7b548 KH |
4034 | static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, |
4035 | unsigned long long *mem_limit, unsigned long long *memsw_limit) | |
4036 | { | |
4037 | struct cgroup *cgroup; | |
4038 | unsigned long long min_limit, min_memsw_limit, tmp; | |
4039 | ||
4040 | min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
4041 | min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
4042 | cgroup = memcg->css.cgroup; | |
4043 | if (!memcg->use_hierarchy) | |
4044 | goto out; | |
4045 | ||
4046 | while (cgroup->parent) { | |
4047 | cgroup = cgroup->parent; | |
4048 | memcg = mem_cgroup_from_cont(cgroup); | |
4049 | if (!memcg->use_hierarchy) | |
4050 | break; | |
4051 | tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
4052 | min_limit = min(min_limit, tmp); | |
4053 | tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
4054 | min_memsw_limit = min(min_memsw_limit, tmp); | |
4055 | } | |
4056 | out: | |
4057 | *mem_limit = min_limit; | |
4058 | *memsw_limit = min_memsw_limit; | |
4059 | return; | |
4060 | } | |
4061 | ||
29f2a4da | 4062 | static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) |
c84872e1 | 4063 | { |
c0ff4b85 | 4064 | struct mem_cgroup *memcg; |
8c7c6e34 | 4065 | int type, name; |
c84872e1 | 4066 | |
c0ff4b85 | 4067 | memcg = mem_cgroup_from_cont(cont); |
8c7c6e34 KH |
4068 | type = MEMFILE_TYPE(event); |
4069 | name = MEMFILE_ATTR(event); | |
4070 | switch (name) { | |
29f2a4da | 4071 | case RES_MAX_USAGE: |
8c7c6e34 | 4072 | if (type == _MEM) |
c0ff4b85 | 4073 | res_counter_reset_max(&memcg->res); |
8c7c6e34 | 4074 | else |
c0ff4b85 | 4075 | res_counter_reset_max(&memcg->memsw); |
29f2a4da PE |
4076 | break; |
4077 | case RES_FAILCNT: | |
8c7c6e34 | 4078 | if (type == _MEM) |
c0ff4b85 | 4079 | res_counter_reset_failcnt(&memcg->res); |
8c7c6e34 | 4080 | else |
c0ff4b85 | 4081 | res_counter_reset_failcnt(&memcg->memsw); |
29f2a4da PE |
4082 | break; |
4083 | } | |
f64c3f54 | 4084 | |
85cc59db | 4085 | return 0; |
c84872e1 PE |
4086 | } |
4087 | ||
7dc74be0 DN |
4088 | static u64 mem_cgroup_move_charge_read(struct cgroup *cgrp, |
4089 | struct cftype *cft) | |
4090 | { | |
4091 | return mem_cgroup_from_cont(cgrp)->move_charge_at_immigrate; | |
4092 | } | |
4093 | ||
02491447 | 4094 | #ifdef CONFIG_MMU |
7dc74be0 DN |
4095 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, |
4096 | struct cftype *cft, u64 val) | |
4097 | { | |
c0ff4b85 | 4098 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
7dc74be0 DN |
4099 | |
4100 | if (val >= (1 << NR_MOVE_TYPE)) | |
4101 | return -EINVAL; | |
4102 | /* | |
4103 | * We check this value several times in both in can_attach() and | |
4104 | * attach(), so we need cgroup lock to prevent this value from being | |
4105 | * inconsistent. | |
4106 | */ | |
4107 | cgroup_lock(); | |
c0ff4b85 | 4108 | memcg->move_charge_at_immigrate = val; |
7dc74be0 DN |
4109 | cgroup_unlock(); |
4110 | ||
4111 | return 0; | |
4112 | } | |
02491447 DN |
4113 | #else |
4114 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, | |
4115 | struct cftype *cft, u64 val) | |
4116 | { | |
4117 | return -ENOSYS; | |
4118 | } | |
4119 | #endif | |
7dc74be0 | 4120 | |
14067bb3 KH |
4121 | |
4122 | /* For read statistics */ | |
4123 | enum { | |
4124 | MCS_CACHE, | |
4125 | MCS_RSS, | |
d8046582 | 4126 | MCS_FILE_MAPPED, |
14067bb3 KH |
4127 | MCS_PGPGIN, |
4128 | MCS_PGPGOUT, | |
1dd3a273 | 4129 | MCS_SWAP, |
456f998e YH |
4130 | MCS_PGFAULT, |
4131 | MCS_PGMAJFAULT, | |
14067bb3 KH |
4132 | MCS_INACTIVE_ANON, |
4133 | MCS_ACTIVE_ANON, | |
4134 | MCS_INACTIVE_FILE, | |
4135 | MCS_ACTIVE_FILE, | |
4136 | MCS_UNEVICTABLE, | |
4137 | NR_MCS_STAT, | |
4138 | }; | |
4139 | ||
4140 | struct mcs_total_stat { | |
4141 | s64 stat[NR_MCS_STAT]; | |
d2ceb9b7 KH |
4142 | }; |
4143 | ||
14067bb3 KH |
4144 | struct { |
4145 | char *local_name; | |
4146 | char *total_name; | |
4147 | } memcg_stat_strings[NR_MCS_STAT] = { | |
4148 | {"cache", "total_cache"}, | |
4149 | {"rss", "total_rss"}, | |
d69b042f | 4150 | {"mapped_file", "total_mapped_file"}, |
14067bb3 KH |
4151 | {"pgpgin", "total_pgpgin"}, |
4152 | {"pgpgout", "total_pgpgout"}, | |
1dd3a273 | 4153 | {"swap", "total_swap"}, |
456f998e YH |
4154 | {"pgfault", "total_pgfault"}, |
4155 | {"pgmajfault", "total_pgmajfault"}, | |
14067bb3 KH |
4156 | {"inactive_anon", "total_inactive_anon"}, |
4157 | {"active_anon", "total_active_anon"}, | |
4158 | {"inactive_file", "total_inactive_file"}, | |
4159 | {"active_file", "total_active_file"}, | |
4160 | {"unevictable", "total_unevictable"} | |
4161 | }; | |
4162 | ||
4163 | ||
7d74b06f | 4164 | static void |
c0ff4b85 | 4165 | mem_cgroup_get_local_stat(struct mem_cgroup *memcg, struct mcs_total_stat *s) |
14067bb3 | 4166 | { |
14067bb3 KH |
4167 | s64 val; |
4168 | ||
4169 | /* per cpu stat */ | |
c0ff4b85 | 4170 | val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_CACHE); |
14067bb3 | 4171 | s->stat[MCS_CACHE] += val * PAGE_SIZE; |
c0ff4b85 | 4172 | val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_RSS); |
14067bb3 | 4173 | s->stat[MCS_RSS] += val * PAGE_SIZE; |
c0ff4b85 | 4174 | val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_FILE_MAPPED); |
d8046582 | 4175 | s->stat[MCS_FILE_MAPPED] += val * PAGE_SIZE; |
c0ff4b85 | 4176 | val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGPGIN); |
14067bb3 | 4177 | s->stat[MCS_PGPGIN] += val; |
c0ff4b85 | 4178 | val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGPGOUT); |
14067bb3 | 4179 | s->stat[MCS_PGPGOUT] += val; |
1dd3a273 | 4180 | if (do_swap_account) { |
c0ff4b85 | 4181 | val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_SWAPOUT); |
1dd3a273 DN |
4182 | s->stat[MCS_SWAP] += val * PAGE_SIZE; |
4183 | } | |
c0ff4b85 | 4184 | val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGFAULT); |
456f998e | 4185 | s->stat[MCS_PGFAULT] += val; |
c0ff4b85 | 4186 | val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGMAJFAULT); |
456f998e | 4187 | s->stat[MCS_PGMAJFAULT] += val; |
14067bb3 KH |
4188 | |
4189 | /* per zone stat */ | |
c0ff4b85 | 4190 | val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_INACTIVE_ANON)); |
14067bb3 | 4191 | s->stat[MCS_INACTIVE_ANON] += val * PAGE_SIZE; |
c0ff4b85 | 4192 | val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_ACTIVE_ANON)); |
14067bb3 | 4193 | s->stat[MCS_ACTIVE_ANON] += val * PAGE_SIZE; |
c0ff4b85 | 4194 | val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_INACTIVE_FILE)); |
14067bb3 | 4195 | s->stat[MCS_INACTIVE_FILE] += val * PAGE_SIZE; |
c0ff4b85 | 4196 | val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_ACTIVE_FILE)); |
14067bb3 | 4197 | s->stat[MCS_ACTIVE_FILE] += val * PAGE_SIZE; |
c0ff4b85 | 4198 | val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_UNEVICTABLE)); |
14067bb3 | 4199 | s->stat[MCS_UNEVICTABLE] += val * PAGE_SIZE; |
14067bb3 KH |
4200 | } |
4201 | ||
4202 | static void | |
c0ff4b85 | 4203 | mem_cgroup_get_total_stat(struct mem_cgroup *memcg, struct mcs_total_stat *s) |
14067bb3 | 4204 | { |
7d74b06f KH |
4205 | struct mem_cgroup *iter; |
4206 | ||
c0ff4b85 | 4207 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 4208 | mem_cgroup_get_local_stat(iter, s); |
14067bb3 KH |
4209 | } |
4210 | ||
406eb0c9 YH |
4211 | #ifdef CONFIG_NUMA |
4212 | static int mem_control_numa_stat_show(struct seq_file *m, void *arg) | |
4213 | { | |
4214 | int nid; | |
4215 | unsigned long total_nr, file_nr, anon_nr, unevictable_nr; | |
4216 | unsigned long node_nr; | |
4217 | struct cgroup *cont = m->private; | |
4218 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); | |
4219 | ||
bb2a0de9 | 4220 | total_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL); |
406eb0c9 YH |
4221 | seq_printf(m, "total=%lu", total_nr); |
4222 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 | 4223 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, LRU_ALL); |
406eb0c9 YH |
4224 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4225 | } | |
4226 | seq_putc(m, '\n'); | |
4227 | ||
bb2a0de9 | 4228 | file_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL_FILE); |
406eb0c9 YH |
4229 | seq_printf(m, "file=%lu", file_nr); |
4230 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4231 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4232 | LRU_ALL_FILE); | |
406eb0c9 YH |
4233 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4234 | } | |
4235 | seq_putc(m, '\n'); | |
4236 | ||
bb2a0de9 | 4237 | anon_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL_ANON); |
406eb0c9 YH |
4238 | seq_printf(m, "anon=%lu", anon_nr); |
4239 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4240 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4241 | LRU_ALL_ANON); | |
406eb0c9 YH |
4242 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4243 | } | |
4244 | seq_putc(m, '\n'); | |
4245 | ||
bb2a0de9 | 4246 | unevictable_nr = mem_cgroup_nr_lru_pages(mem_cont, BIT(LRU_UNEVICTABLE)); |
406eb0c9 YH |
4247 | seq_printf(m, "unevictable=%lu", unevictable_nr); |
4248 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4249 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4250 | BIT(LRU_UNEVICTABLE)); | |
406eb0c9 YH |
4251 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4252 | } | |
4253 | seq_putc(m, '\n'); | |
4254 | return 0; | |
4255 | } | |
4256 | #endif /* CONFIG_NUMA */ | |
4257 | ||
c64745cf PM |
4258 | static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, |
4259 | struct cgroup_map_cb *cb) | |
d2ceb9b7 | 4260 | { |
d2ceb9b7 | 4261 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); |
14067bb3 | 4262 | struct mcs_total_stat mystat; |
d2ceb9b7 KH |
4263 | int i; |
4264 | ||
14067bb3 KH |
4265 | memset(&mystat, 0, sizeof(mystat)); |
4266 | mem_cgroup_get_local_stat(mem_cont, &mystat); | |
d2ceb9b7 | 4267 | |
406eb0c9 | 4268 | |
1dd3a273 DN |
4269 | for (i = 0; i < NR_MCS_STAT; i++) { |
4270 | if (i == MCS_SWAP && !do_swap_account) | |
4271 | continue; | |
14067bb3 | 4272 | cb->fill(cb, memcg_stat_strings[i].local_name, mystat.stat[i]); |
1dd3a273 | 4273 | } |
7b854121 | 4274 | |
14067bb3 | 4275 | /* Hierarchical information */ |
fee7b548 KH |
4276 | { |
4277 | unsigned long long limit, memsw_limit; | |
4278 | memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit); | |
4279 | cb->fill(cb, "hierarchical_memory_limit", limit); | |
4280 | if (do_swap_account) | |
4281 | cb->fill(cb, "hierarchical_memsw_limit", memsw_limit); | |
4282 | } | |
7f016ee8 | 4283 | |
14067bb3 KH |
4284 | memset(&mystat, 0, sizeof(mystat)); |
4285 | mem_cgroup_get_total_stat(mem_cont, &mystat); | |
1dd3a273 DN |
4286 | for (i = 0; i < NR_MCS_STAT; i++) { |
4287 | if (i == MCS_SWAP && !do_swap_account) | |
4288 | continue; | |
14067bb3 | 4289 | cb->fill(cb, memcg_stat_strings[i].total_name, mystat.stat[i]); |
1dd3a273 | 4290 | } |
14067bb3 | 4291 | |
7f016ee8 | 4292 | #ifdef CONFIG_DEBUG_VM |
7f016ee8 KM |
4293 | { |
4294 | int nid, zid; | |
4295 | struct mem_cgroup_per_zone *mz; | |
4296 | unsigned long recent_rotated[2] = {0, 0}; | |
4297 | unsigned long recent_scanned[2] = {0, 0}; | |
4298 | ||
4299 | for_each_online_node(nid) | |
4300 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
4301 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); | |
4302 | ||
4303 | recent_rotated[0] += | |
4304 | mz->reclaim_stat.recent_rotated[0]; | |
4305 | recent_rotated[1] += | |
4306 | mz->reclaim_stat.recent_rotated[1]; | |
4307 | recent_scanned[0] += | |
4308 | mz->reclaim_stat.recent_scanned[0]; | |
4309 | recent_scanned[1] += | |
4310 | mz->reclaim_stat.recent_scanned[1]; | |
4311 | } | |
4312 | cb->fill(cb, "recent_rotated_anon", recent_rotated[0]); | |
4313 | cb->fill(cb, "recent_rotated_file", recent_rotated[1]); | |
4314 | cb->fill(cb, "recent_scanned_anon", recent_scanned[0]); | |
4315 | cb->fill(cb, "recent_scanned_file", recent_scanned[1]); | |
4316 | } | |
4317 | #endif | |
4318 | ||
d2ceb9b7 KH |
4319 | return 0; |
4320 | } | |
4321 | ||
a7885eb8 KM |
4322 | static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft) |
4323 | { | |
4324 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4325 | ||
1f4c025b | 4326 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
4327 | } |
4328 | ||
4329 | static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, | |
4330 | u64 val) | |
4331 | { | |
4332 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4333 | struct mem_cgroup *parent; | |
068b38c1 | 4334 | |
a7885eb8 KM |
4335 | if (val > 100) |
4336 | return -EINVAL; | |
4337 | ||
4338 | if (cgrp->parent == NULL) | |
4339 | return -EINVAL; | |
4340 | ||
4341 | parent = mem_cgroup_from_cont(cgrp->parent); | |
068b38c1 LZ |
4342 | |
4343 | cgroup_lock(); | |
4344 | ||
a7885eb8 KM |
4345 | /* If under hierarchy, only empty-root can set this value */ |
4346 | if ((parent->use_hierarchy) || | |
068b38c1 LZ |
4347 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
4348 | cgroup_unlock(); | |
a7885eb8 | 4349 | return -EINVAL; |
068b38c1 | 4350 | } |
a7885eb8 | 4351 | |
a7885eb8 | 4352 | memcg->swappiness = val; |
a7885eb8 | 4353 | |
068b38c1 LZ |
4354 | cgroup_unlock(); |
4355 | ||
a7885eb8 KM |
4356 | return 0; |
4357 | } | |
4358 | ||
2e72b634 KS |
4359 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
4360 | { | |
4361 | struct mem_cgroup_threshold_ary *t; | |
4362 | u64 usage; | |
4363 | int i; | |
4364 | ||
4365 | rcu_read_lock(); | |
4366 | if (!swap) | |
2c488db2 | 4367 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 4368 | else |
2c488db2 | 4369 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
4370 | |
4371 | if (!t) | |
4372 | goto unlock; | |
4373 | ||
4374 | usage = mem_cgroup_usage(memcg, swap); | |
4375 | ||
4376 | /* | |
4377 | * current_threshold points to threshold just below usage. | |
4378 | * If it's not true, a threshold was crossed after last | |
4379 | * call of __mem_cgroup_threshold(). | |
4380 | */ | |
5407a562 | 4381 | i = t->current_threshold; |
2e72b634 KS |
4382 | |
4383 | /* | |
4384 | * Iterate backward over array of thresholds starting from | |
4385 | * current_threshold and check if a threshold is crossed. | |
4386 | * If none of thresholds below usage is crossed, we read | |
4387 | * only one element of the array here. | |
4388 | */ | |
4389 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
4390 | eventfd_signal(t->entries[i].eventfd, 1); | |
4391 | ||
4392 | /* i = current_threshold + 1 */ | |
4393 | i++; | |
4394 | ||
4395 | /* | |
4396 | * Iterate forward over array of thresholds starting from | |
4397 | * current_threshold+1 and check if a threshold is crossed. | |
4398 | * If none of thresholds above usage is crossed, we read | |
4399 | * only one element of the array here. | |
4400 | */ | |
4401 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
4402 | eventfd_signal(t->entries[i].eventfd, 1); | |
4403 | ||
4404 | /* Update current_threshold */ | |
5407a562 | 4405 | t->current_threshold = i - 1; |
2e72b634 KS |
4406 | unlock: |
4407 | rcu_read_unlock(); | |
4408 | } | |
4409 | ||
4410 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
4411 | { | |
ad4ca5f4 KS |
4412 | while (memcg) { |
4413 | __mem_cgroup_threshold(memcg, false); | |
4414 | if (do_swap_account) | |
4415 | __mem_cgroup_threshold(memcg, true); | |
4416 | ||
4417 | memcg = parent_mem_cgroup(memcg); | |
4418 | } | |
2e72b634 KS |
4419 | } |
4420 | ||
4421 | static int compare_thresholds(const void *a, const void *b) | |
4422 | { | |
4423 | const struct mem_cgroup_threshold *_a = a; | |
4424 | const struct mem_cgroup_threshold *_b = b; | |
4425 | ||
4426 | return _a->threshold - _b->threshold; | |
4427 | } | |
4428 | ||
c0ff4b85 | 4429 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg) |
9490ff27 KH |
4430 | { |
4431 | struct mem_cgroup_eventfd_list *ev; | |
4432 | ||
c0ff4b85 | 4433 | list_for_each_entry(ev, &memcg->oom_notify, list) |
9490ff27 KH |
4434 | eventfd_signal(ev->eventfd, 1); |
4435 | return 0; | |
4436 | } | |
4437 | ||
c0ff4b85 | 4438 | static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) |
9490ff27 | 4439 | { |
7d74b06f KH |
4440 | struct mem_cgroup *iter; |
4441 | ||
c0ff4b85 | 4442 | for_each_mem_cgroup_tree(iter, memcg) |
7d74b06f | 4443 | mem_cgroup_oom_notify_cb(iter); |
9490ff27 KH |
4444 | } |
4445 | ||
4446 | static int mem_cgroup_usage_register_event(struct cgroup *cgrp, | |
4447 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
2e72b634 KS |
4448 | { |
4449 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4450 | struct mem_cgroup_thresholds *thresholds; |
4451 | struct mem_cgroup_threshold_ary *new; | |
2e72b634 KS |
4452 | int type = MEMFILE_TYPE(cft->private); |
4453 | u64 threshold, usage; | |
2c488db2 | 4454 | int i, size, ret; |
2e72b634 KS |
4455 | |
4456 | ret = res_counter_memparse_write_strategy(args, &threshold); | |
4457 | if (ret) | |
4458 | return ret; | |
4459 | ||
4460 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 4461 | |
2e72b634 | 4462 | if (type == _MEM) |
2c488db2 | 4463 | thresholds = &memcg->thresholds; |
2e72b634 | 4464 | else if (type == _MEMSWAP) |
2c488db2 | 4465 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4466 | else |
4467 | BUG(); | |
4468 | ||
4469 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4470 | ||
4471 | /* Check if a threshold crossed before adding a new one */ | |
2c488db2 | 4472 | if (thresholds->primary) |
2e72b634 KS |
4473 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4474 | ||
2c488db2 | 4475 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
4476 | |
4477 | /* Allocate memory for new array of thresholds */ | |
2c488db2 | 4478 | new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold), |
2e72b634 | 4479 | GFP_KERNEL); |
2c488db2 | 4480 | if (!new) { |
2e72b634 KS |
4481 | ret = -ENOMEM; |
4482 | goto unlock; | |
4483 | } | |
2c488db2 | 4484 | new->size = size; |
2e72b634 KS |
4485 | |
4486 | /* Copy thresholds (if any) to new array */ | |
2c488db2 KS |
4487 | if (thresholds->primary) { |
4488 | memcpy(new->entries, thresholds->primary->entries, (size - 1) * | |
2e72b634 | 4489 | sizeof(struct mem_cgroup_threshold)); |
2c488db2 KS |
4490 | } |
4491 | ||
2e72b634 | 4492 | /* Add new threshold */ |
2c488db2 KS |
4493 | new->entries[size - 1].eventfd = eventfd; |
4494 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
4495 | |
4496 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
2c488db2 | 4497 | sort(new->entries, size, sizeof(struct mem_cgroup_threshold), |
2e72b634 KS |
4498 | compare_thresholds, NULL); |
4499 | ||
4500 | /* Find current threshold */ | |
2c488db2 | 4501 | new->current_threshold = -1; |
2e72b634 | 4502 | for (i = 0; i < size; i++) { |
2c488db2 | 4503 | if (new->entries[i].threshold < usage) { |
2e72b634 | 4504 | /* |
2c488db2 KS |
4505 | * new->current_threshold will not be used until |
4506 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
4507 | * it here. |
4508 | */ | |
2c488db2 | 4509 | ++new->current_threshold; |
2e72b634 KS |
4510 | } |
4511 | } | |
4512 | ||
2c488db2 KS |
4513 | /* Free old spare buffer and save old primary buffer as spare */ |
4514 | kfree(thresholds->spare); | |
4515 | thresholds->spare = thresholds->primary; | |
4516 | ||
4517 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4518 | |
907860ed | 4519 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4520 | synchronize_rcu(); |
4521 | ||
2e72b634 KS |
4522 | unlock: |
4523 | mutex_unlock(&memcg->thresholds_lock); | |
4524 | ||
4525 | return ret; | |
4526 | } | |
4527 | ||
907860ed | 4528 | static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp, |
9490ff27 | 4529 | struct cftype *cft, struct eventfd_ctx *eventfd) |
2e72b634 KS |
4530 | { |
4531 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4532 | struct mem_cgroup_thresholds *thresholds; |
4533 | struct mem_cgroup_threshold_ary *new; | |
2e72b634 KS |
4534 | int type = MEMFILE_TYPE(cft->private); |
4535 | u64 usage; | |
2c488db2 | 4536 | int i, j, size; |
2e72b634 KS |
4537 | |
4538 | mutex_lock(&memcg->thresholds_lock); | |
4539 | if (type == _MEM) | |
2c488db2 | 4540 | thresholds = &memcg->thresholds; |
2e72b634 | 4541 | else if (type == _MEMSWAP) |
2c488db2 | 4542 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4543 | else |
4544 | BUG(); | |
4545 | ||
4546 | /* | |
4547 | * Something went wrong if we trying to unregister a threshold | |
4548 | * if we don't have thresholds | |
4549 | */ | |
4550 | BUG_ON(!thresholds); | |
4551 | ||
4552 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4553 | ||
4554 | /* Check if a threshold crossed before removing */ | |
4555 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
4556 | ||
4557 | /* Calculate new number of threshold */ | |
2c488db2 KS |
4558 | size = 0; |
4559 | for (i = 0; i < thresholds->primary->size; i++) { | |
4560 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 KS |
4561 | size++; |
4562 | } | |
4563 | ||
2c488db2 | 4564 | new = thresholds->spare; |
907860ed | 4565 | |
2e72b634 KS |
4566 | /* Set thresholds array to NULL if we don't have thresholds */ |
4567 | if (!size) { | |
2c488db2 KS |
4568 | kfree(new); |
4569 | new = NULL; | |
907860ed | 4570 | goto swap_buffers; |
2e72b634 KS |
4571 | } |
4572 | ||
2c488db2 | 4573 | new->size = size; |
2e72b634 KS |
4574 | |
4575 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
4576 | new->current_threshold = -1; |
4577 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
4578 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
4579 | continue; |
4580 | ||
2c488db2 KS |
4581 | new->entries[j] = thresholds->primary->entries[i]; |
4582 | if (new->entries[j].threshold < usage) { | |
2e72b634 | 4583 | /* |
2c488db2 | 4584 | * new->current_threshold will not be used |
2e72b634 KS |
4585 | * until rcu_assign_pointer(), so it's safe to increment |
4586 | * it here. | |
4587 | */ | |
2c488db2 | 4588 | ++new->current_threshold; |
2e72b634 KS |
4589 | } |
4590 | j++; | |
4591 | } | |
4592 | ||
907860ed | 4593 | swap_buffers: |
2c488db2 KS |
4594 | /* Swap primary and spare array */ |
4595 | thresholds->spare = thresholds->primary; | |
4596 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4597 | |
907860ed | 4598 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4599 | synchronize_rcu(); |
4600 | ||
2e72b634 | 4601 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 4602 | } |
c1e862c1 | 4603 | |
9490ff27 KH |
4604 | static int mem_cgroup_oom_register_event(struct cgroup *cgrp, |
4605 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
4606 | { | |
4607 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4608 | struct mem_cgroup_eventfd_list *event; | |
4609 | int type = MEMFILE_TYPE(cft->private); | |
4610 | ||
4611 | BUG_ON(type != _OOM_TYPE); | |
4612 | event = kmalloc(sizeof(*event), GFP_KERNEL); | |
4613 | if (!event) | |
4614 | return -ENOMEM; | |
4615 | ||
1af8efe9 | 4616 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4617 | |
4618 | event->eventfd = eventfd; | |
4619 | list_add(&event->list, &memcg->oom_notify); | |
4620 | ||
4621 | /* already in OOM ? */ | |
79dfdacc | 4622 | if (atomic_read(&memcg->under_oom)) |
9490ff27 | 4623 | eventfd_signal(eventfd, 1); |
1af8efe9 | 4624 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4625 | |
4626 | return 0; | |
4627 | } | |
4628 | ||
907860ed | 4629 | static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp, |
9490ff27 KH |
4630 | struct cftype *cft, struct eventfd_ctx *eventfd) |
4631 | { | |
c0ff4b85 | 4632 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
9490ff27 KH |
4633 | struct mem_cgroup_eventfd_list *ev, *tmp; |
4634 | int type = MEMFILE_TYPE(cft->private); | |
4635 | ||
4636 | BUG_ON(type != _OOM_TYPE); | |
4637 | ||
1af8efe9 | 4638 | spin_lock(&memcg_oom_lock); |
9490ff27 | 4639 | |
c0ff4b85 | 4640 | list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) { |
9490ff27 KH |
4641 | if (ev->eventfd == eventfd) { |
4642 | list_del(&ev->list); | |
4643 | kfree(ev); | |
4644 | } | |
4645 | } | |
4646 | ||
1af8efe9 | 4647 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4648 | } |
4649 | ||
3c11ecf4 KH |
4650 | static int mem_cgroup_oom_control_read(struct cgroup *cgrp, |
4651 | struct cftype *cft, struct cgroup_map_cb *cb) | |
4652 | { | |
c0ff4b85 | 4653 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
3c11ecf4 | 4654 | |
c0ff4b85 | 4655 | cb->fill(cb, "oom_kill_disable", memcg->oom_kill_disable); |
3c11ecf4 | 4656 | |
c0ff4b85 | 4657 | if (atomic_read(&memcg->under_oom)) |
3c11ecf4 KH |
4658 | cb->fill(cb, "under_oom", 1); |
4659 | else | |
4660 | cb->fill(cb, "under_oom", 0); | |
4661 | return 0; | |
4662 | } | |
4663 | ||
3c11ecf4 KH |
4664 | static int mem_cgroup_oom_control_write(struct cgroup *cgrp, |
4665 | struct cftype *cft, u64 val) | |
4666 | { | |
c0ff4b85 | 4667 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
3c11ecf4 KH |
4668 | struct mem_cgroup *parent; |
4669 | ||
4670 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
4671 | if (!cgrp->parent || !((val == 0) || (val == 1))) | |
4672 | return -EINVAL; | |
4673 | ||
4674 | parent = mem_cgroup_from_cont(cgrp->parent); | |
4675 | ||
4676 | cgroup_lock(); | |
4677 | /* oom-kill-disable is a flag for subhierarchy. */ | |
4678 | if ((parent->use_hierarchy) || | |
c0ff4b85 | 4679 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
3c11ecf4 KH |
4680 | cgroup_unlock(); |
4681 | return -EINVAL; | |
4682 | } | |
c0ff4b85 | 4683 | memcg->oom_kill_disable = val; |
4d845ebf | 4684 | if (!val) |
c0ff4b85 | 4685 | memcg_oom_recover(memcg); |
3c11ecf4 KH |
4686 | cgroup_unlock(); |
4687 | return 0; | |
4688 | } | |
4689 | ||
406eb0c9 YH |
4690 | #ifdef CONFIG_NUMA |
4691 | static const struct file_operations mem_control_numa_stat_file_operations = { | |
4692 | .read = seq_read, | |
4693 | .llseek = seq_lseek, | |
4694 | .release = single_release, | |
4695 | }; | |
4696 | ||
4697 | static int mem_control_numa_stat_open(struct inode *unused, struct file *file) | |
4698 | { | |
4699 | struct cgroup *cont = file->f_dentry->d_parent->d_fsdata; | |
4700 | ||
4701 | file->f_op = &mem_control_numa_stat_file_operations; | |
4702 | return single_open(file, mem_control_numa_stat_show, cont); | |
4703 | } | |
4704 | #endif /* CONFIG_NUMA */ | |
4705 | ||
e5671dfa | 4706 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM |
e5671dfa GC |
4707 | static int register_kmem_files(struct cgroup *cont, struct cgroup_subsys *ss) |
4708 | { | |
d1a4c0b3 GC |
4709 | /* |
4710 | * Part of this would be better living in a separate allocation | |
4711 | * function, leaving us with just the cgroup tree population work. | |
4712 | * We, however, depend on state such as network's proto_list that | |
4713 | * is only initialized after cgroup creation. I found the less | |
4714 | * cumbersome way to deal with it to defer it all to populate time | |
4715 | */ | |
65c64ce8 | 4716 | return mem_cgroup_sockets_init(cont, ss); |
e5671dfa GC |
4717 | }; |
4718 | ||
d1a4c0b3 GC |
4719 | static void kmem_cgroup_destroy(struct cgroup_subsys *ss, |
4720 | struct cgroup *cont) | |
4721 | { | |
4722 | mem_cgroup_sockets_destroy(cont, ss); | |
4723 | } | |
e5671dfa GC |
4724 | #else |
4725 | static int register_kmem_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4726 | { | |
4727 | return 0; | |
4728 | } | |
d1a4c0b3 GC |
4729 | |
4730 | static void kmem_cgroup_destroy(struct cgroup_subsys *ss, | |
4731 | struct cgroup *cont) | |
4732 | { | |
4733 | } | |
e5671dfa GC |
4734 | #endif |
4735 | ||
8cdea7c0 BS |
4736 | static struct cftype mem_cgroup_files[] = { |
4737 | { | |
0eea1030 | 4738 | .name = "usage_in_bytes", |
8c7c6e34 | 4739 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
2c3daa72 | 4740 | .read_u64 = mem_cgroup_read, |
9490ff27 KH |
4741 | .register_event = mem_cgroup_usage_register_event, |
4742 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8cdea7c0 | 4743 | }, |
c84872e1 PE |
4744 | { |
4745 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 4746 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
29f2a4da | 4747 | .trigger = mem_cgroup_reset, |
c84872e1 PE |
4748 | .read_u64 = mem_cgroup_read, |
4749 | }, | |
8cdea7c0 | 4750 | { |
0eea1030 | 4751 | .name = "limit_in_bytes", |
8c7c6e34 | 4752 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
856c13aa | 4753 | .write_string = mem_cgroup_write, |
2c3daa72 | 4754 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 4755 | }, |
296c81d8 BS |
4756 | { |
4757 | .name = "soft_limit_in_bytes", | |
4758 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
4759 | .write_string = mem_cgroup_write, | |
4760 | .read_u64 = mem_cgroup_read, | |
4761 | }, | |
8cdea7c0 BS |
4762 | { |
4763 | .name = "failcnt", | |
8c7c6e34 | 4764 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
29f2a4da | 4765 | .trigger = mem_cgroup_reset, |
2c3daa72 | 4766 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 4767 | }, |
d2ceb9b7 KH |
4768 | { |
4769 | .name = "stat", | |
c64745cf | 4770 | .read_map = mem_control_stat_show, |
d2ceb9b7 | 4771 | }, |
c1e862c1 KH |
4772 | { |
4773 | .name = "force_empty", | |
4774 | .trigger = mem_cgroup_force_empty_write, | |
4775 | }, | |
18f59ea7 BS |
4776 | { |
4777 | .name = "use_hierarchy", | |
4778 | .write_u64 = mem_cgroup_hierarchy_write, | |
4779 | .read_u64 = mem_cgroup_hierarchy_read, | |
4780 | }, | |
a7885eb8 KM |
4781 | { |
4782 | .name = "swappiness", | |
4783 | .read_u64 = mem_cgroup_swappiness_read, | |
4784 | .write_u64 = mem_cgroup_swappiness_write, | |
4785 | }, | |
7dc74be0 DN |
4786 | { |
4787 | .name = "move_charge_at_immigrate", | |
4788 | .read_u64 = mem_cgroup_move_charge_read, | |
4789 | .write_u64 = mem_cgroup_move_charge_write, | |
4790 | }, | |
9490ff27 KH |
4791 | { |
4792 | .name = "oom_control", | |
3c11ecf4 KH |
4793 | .read_map = mem_cgroup_oom_control_read, |
4794 | .write_u64 = mem_cgroup_oom_control_write, | |
9490ff27 KH |
4795 | .register_event = mem_cgroup_oom_register_event, |
4796 | .unregister_event = mem_cgroup_oom_unregister_event, | |
4797 | .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), | |
4798 | }, | |
406eb0c9 YH |
4799 | #ifdef CONFIG_NUMA |
4800 | { | |
4801 | .name = "numa_stat", | |
4802 | .open = mem_control_numa_stat_open, | |
89577127 | 4803 | .mode = S_IRUGO, |
406eb0c9 YH |
4804 | }, |
4805 | #endif | |
8cdea7c0 BS |
4806 | }; |
4807 | ||
8c7c6e34 KH |
4808 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4809 | static struct cftype memsw_cgroup_files[] = { | |
4810 | { | |
4811 | .name = "memsw.usage_in_bytes", | |
4812 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
4813 | .read_u64 = mem_cgroup_read, | |
9490ff27 KH |
4814 | .register_event = mem_cgroup_usage_register_event, |
4815 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8c7c6e34 KH |
4816 | }, |
4817 | { | |
4818 | .name = "memsw.max_usage_in_bytes", | |
4819 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
4820 | .trigger = mem_cgroup_reset, | |
4821 | .read_u64 = mem_cgroup_read, | |
4822 | }, | |
4823 | { | |
4824 | .name = "memsw.limit_in_bytes", | |
4825 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
4826 | .write_string = mem_cgroup_write, | |
4827 | .read_u64 = mem_cgroup_read, | |
4828 | }, | |
4829 | { | |
4830 | .name = "memsw.failcnt", | |
4831 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
4832 | .trigger = mem_cgroup_reset, | |
4833 | .read_u64 = mem_cgroup_read, | |
4834 | }, | |
4835 | }; | |
4836 | ||
4837 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4838 | { | |
4839 | if (!do_swap_account) | |
4840 | return 0; | |
4841 | return cgroup_add_files(cont, ss, memsw_cgroup_files, | |
4842 | ARRAY_SIZE(memsw_cgroup_files)); | |
4843 | }; | |
4844 | #else | |
4845 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4846 | { | |
4847 | return 0; | |
4848 | } | |
4849 | #endif | |
4850 | ||
c0ff4b85 | 4851 | static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) |
6d12e2d8 KH |
4852 | { |
4853 | struct mem_cgroup_per_node *pn; | |
1ecaab2b | 4854 | struct mem_cgroup_per_zone *mz; |
b69408e8 | 4855 | enum lru_list l; |
41e3355d | 4856 | int zone, tmp = node; |
1ecaab2b KH |
4857 | /* |
4858 | * This routine is called against possible nodes. | |
4859 | * But it's BUG to call kmalloc() against offline node. | |
4860 | * | |
4861 | * TODO: this routine can waste much memory for nodes which will | |
4862 | * never be onlined. It's better to use memory hotplug callback | |
4863 | * function. | |
4864 | */ | |
41e3355d KH |
4865 | if (!node_state(node, N_NORMAL_MEMORY)) |
4866 | tmp = -1; | |
17295c88 | 4867 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); |
6d12e2d8 KH |
4868 | if (!pn) |
4869 | return 1; | |
1ecaab2b | 4870 | |
1ecaab2b KH |
4871 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
4872 | mz = &pn->zoneinfo[zone]; | |
b69408e8 CL |
4873 | for_each_lru(l) |
4874 | INIT_LIST_HEAD(&mz->lists[l]); | |
f64c3f54 | 4875 | mz->usage_in_excess = 0; |
4e416953 | 4876 | mz->on_tree = false; |
c0ff4b85 | 4877 | mz->mem = memcg; |
1ecaab2b | 4878 | } |
0a619e58 | 4879 | memcg->info.nodeinfo[node] = pn; |
6d12e2d8 KH |
4880 | return 0; |
4881 | } | |
4882 | ||
c0ff4b85 | 4883 | static void free_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) |
1ecaab2b | 4884 | { |
c0ff4b85 | 4885 | kfree(memcg->info.nodeinfo[node]); |
1ecaab2b KH |
4886 | } |
4887 | ||
33327948 KH |
4888 | static struct mem_cgroup *mem_cgroup_alloc(void) |
4889 | { | |
4890 | struct mem_cgroup *mem; | |
c62b1a3b | 4891 | int size = sizeof(struct mem_cgroup); |
33327948 | 4892 | |
c62b1a3b | 4893 | /* Can be very big if MAX_NUMNODES is very big */ |
c8dad2bb | 4894 | if (size < PAGE_SIZE) |
17295c88 | 4895 | mem = kzalloc(size, GFP_KERNEL); |
33327948 | 4896 | else |
17295c88 | 4897 | mem = vzalloc(size); |
33327948 | 4898 | |
e7bbcdf3 DC |
4899 | if (!mem) |
4900 | return NULL; | |
4901 | ||
c62b1a3b | 4902 | mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu); |
d2e61b8d DC |
4903 | if (!mem->stat) |
4904 | goto out_free; | |
711d3d2c | 4905 | spin_lock_init(&mem->pcp_counter_lock); |
33327948 | 4906 | return mem; |
d2e61b8d DC |
4907 | |
4908 | out_free: | |
4909 | if (size < PAGE_SIZE) | |
4910 | kfree(mem); | |
4911 | else | |
4912 | vfree(mem); | |
4913 | return NULL; | |
33327948 KH |
4914 | } |
4915 | ||
8c7c6e34 KH |
4916 | /* |
4917 | * At destroying mem_cgroup, references from swap_cgroup can remain. | |
4918 | * (scanning all at force_empty is too costly...) | |
4919 | * | |
4920 | * Instead of clearing all references at force_empty, we remember | |
4921 | * the number of reference from swap_cgroup and free mem_cgroup when | |
4922 | * it goes down to 0. | |
4923 | * | |
8c7c6e34 KH |
4924 | * Removal of cgroup itself succeeds regardless of refs from swap. |
4925 | */ | |
4926 | ||
c0ff4b85 | 4927 | static void __mem_cgroup_free(struct mem_cgroup *memcg) |
33327948 | 4928 | { |
08e552c6 KH |
4929 | int node; |
4930 | ||
c0ff4b85 R |
4931 | mem_cgroup_remove_from_trees(memcg); |
4932 | free_css_id(&mem_cgroup_subsys, &memcg->css); | |
04046e1a | 4933 | |
08e552c6 | 4934 | for_each_node_state(node, N_POSSIBLE) |
c0ff4b85 | 4935 | free_mem_cgroup_per_zone_info(memcg, node); |
08e552c6 | 4936 | |
c0ff4b85 | 4937 | free_percpu(memcg->stat); |
c62b1a3b | 4938 | if (sizeof(struct mem_cgroup) < PAGE_SIZE) |
c0ff4b85 | 4939 | kfree(memcg); |
33327948 | 4940 | else |
c0ff4b85 | 4941 | vfree(memcg); |
33327948 KH |
4942 | } |
4943 | ||
c0ff4b85 | 4944 | static void mem_cgroup_get(struct mem_cgroup *memcg) |
8c7c6e34 | 4945 | { |
c0ff4b85 | 4946 | atomic_inc(&memcg->refcnt); |
8c7c6e34 KH |
4947 | } |
4948 | ||
c0ff4b85 | 4949 | static void __mem_cgroup_put(struct mem_cgroup *memcg, int count) |
8c7c6e34 | 4950 | { |
c0ff4b85 R |
4951 | if (atomic_sub_and_test(count, &memcg->refcnt)) { |
4952 | struct mem_cgroup *parent = parent_mem_cgroup(memcg); | |
4953 | __mem_cgroup_free(memcg); | |
7bcc1bb1 DN |
4954 | if (parent) |
4955 | mem_cgroup_put(parent); | |
4956 | } | |
8c7c6e34 KH |
4957 | } |
4958 | ||
c0ff4b85 | 4959 | static void mem_cgroup_put(struct mem_cgroup *memcg) |
483c30b5 | 4960 | { |
c0ff4b85 | 4961 | __mem_cgroup_put(memcg, 1); |
483c30b5 DN |
4962 | } |
4963 | ||
7bcc1bb1 DN |
4964 | /* |
4965 | * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. | |
4966 | */ | |
e1aab161 | 4967 | struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) |
7bcc1bb1 | 4968 | { |
c0ff4b85 | 4969 | if (!memcg->res.parent) |
7bcc1bb1 | 4970 | return NULL; |
c0ff4b85 | 4971 | return mem_cgroup_from_res_counter(memcg->res.parent, res); |
7bcc1bb1 | 4972 | } |
e1aab161 | 4973 | EXPORT_SYMBOL(parent_mem_cgroup); |
33327948 | 4974 | |
c077719b KH |
4975 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4976 | static void __init enable_swap_cgroup(void) | |
4977 | { | |
f8d66542 | 4978 | if (!mem_cgroup_disabled() && really_do_swap_account) |
c077719b KH |
4979 | do_swap_account = 1; |
4980 | } | |
4981 | #else | |
4982 | static void __init enable_swap_cgroup(void) | |
4983 | { | |
4984 | } | |
4985 | #endif | |
4986 | ||
f64c3f54 BS |
4987 | static int mem_cgroup_soft_limit_tree_init(void) |
4988 | { | |
4989 | struct mem_cgroup_tree_per_node *rtpn; | |
4990 | struct mem_cgroup_tree_per_zone *rtpz; | |
4991 | int tmp, node, zone; | |
4992 | ||
4993 | for_each_node_state(node, N_POSSIBLE) { | |
4994 | tmp = node; | |
4995 | if (!node_state(node, N_NORMAL_MEMORY)) | |
4996 | tmp = -1; | |
4997 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, tmp); | |
4998 | if (!rtpn) | |
4999 | return 1; | |
5000 | ||
5001 | soft_limit_tree.rb_tree_per_node[node] = rtpn; | |
5002 | ||
5003 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
5004 | rtpz = &rtpn->rb_tree_per_zone[zone]; | |
5005 | rtpz->rb_root = RB_ROOT; | |
5006 | spin_lock_init(&rtpz->lock); | |
5007 | } | |
5008 | } | |
5009 | return 0; | |
5010 | } | |
5011 | ||
0eb253e2 | 5012 | static struct cgroup_subsys_state * __ref |
8cdea7c0 BS |
5013 | mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) |
5014 | { | |
c0ff4b85 | 5015 | struct mem_cgroup *memcg, *parent; |
04046e1a | 5016 | long error = -ENOMEM; |
6d12e2d8 | 5017 | int node; |
8cdea7c0 | 5018 | |
c0ff4b85 R |
5019 | memcg = mem_cgroup_alloc(); |
5020 | if (!memcg) | |
04046e1a | 5021 | return ERR_PTR(error); |
78fb7466 | 5022 | |
6d12e2d8 | 5023 | for_each_node_state(node, N_POSSIBLE) |
c0ff4b85 | 5024 | if (alloc_mem_cgroup_per_zone_info(memcg, node)) |
6d12e2d8 | 5025 | goto free_out; |
f64c3f54 | 5026 | |
c077719b | 5027 | /* root ? */ |
28dbc4b6 | 5028 | if (cont->parent == NULL) { |
cdec2e42 | 5029 | int cpu; |
c077719b | 5030 | enable_swap_cgroup(); |
28dbc4b6 | 5031 | parent = NULL; |
f64c3f54 BS |
5032 | if (mem_cgroup_soft_limit_tree_init()) |
5033 | goto free_out; | |
a41c58a6 | 5034 | root_mem_cgroup = memcg; |
cdec2e42 KH |
5035 | for_each_possible_cpu(cpu) { |
5036 | struct memcg_stock_pcp *stock = | |
5037 | &per_cpu(memcg_stock, cpu); | |
5038 | INIT_WORK(&stock->work, drain_local_stock); | |
5039 | } | |
711d3d2c | 5040 | hotcpu_notifier(memcg_cpu_hotplug_callback, 0); |
18f59ea7 | 5041 | } else { |
28dbc4b6 | 5042 | parent = mem_cgroup_from_cont(cont->parent); |
c0ff4b85 R |
5043 | memcg->use_hierarchy = parent->use_hierarchy; |
5044 | memcg->oom_kill_disable = parent->oom_kill_disable; | |
18f59ea7 | 5045 | } |
28dbc4b6 | 5046 | |
18f59ea7 | 5047 | if (parent && parent->use_hierarchy) { |
c0ff4b85 R |
5048 | res_counter_init(&memcg->res, &parent->res); |
5049 | res_counter_init(&memcg->memsw, &parent->memsw); | |
7bcc1bb1 DN |
5050 | /* |
5051 | * We increment refcnt of the parent to ensure that we can | |
5052 | * safely access it on res_counter_charge/uncharge. | |
5053 | * This refcnt will be decremented when freeing this | |
5054 | * mem_cgroup(see mem_cgroup_put). | |
5055 | */ | |
5056 | mem_cgroup_get(parent); | |
18f59ea7 | 5057 | } else { |
c0ff4b85 R |
5058 | res_counter_init(&memcg->res, NULL); |
5059 | res_counter_init(&memcg->memsw, NULL); | |
18f59ea7 | 5060 | } |
c0ff4b85 R |
5061 | memcg->last_scanned_node = MAX_NUMNODES; |
5062 | INIT_LIST_HEAD(&memcg->oom_notify); | |
6d61ef40 | 5063 | |
a7885eb8 | 5064 | if (parent) |
c0ff4b85 R |
5065 | memcg->swappiness = mem_cgroup_swappiness(parent); |
5066 | atomic_set(&memcg->refcnt, 1); | |
5067 | memcg->move_charge_at_immigrate = 0; | |
5068 | mutex_init(&memcg->thresholds_lock); | |
5069 | return &memcg->css; | |
6d12e2d8 | 5070 | free_out: |
c0ff4b85 | 5071 | __mem_cgroup_free(memcg); |
04046e1a | 5072 | return ERR_PTR(error); |
8cdea7c0 BS |
5073 | } |
5074 | ||
ec64f515 | 5075 | static int mem_cgroup_pre_destroy(struct cgroup_subsys *ss, |
df878fb0 KH |
5076 | struct cgroup *cont) |
5077 | { | |
c0ff4b85 | 5078 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
ec64f515 | 5079 | |
c0ff4b85 | 5080 | return mem_cgroup_force_empty(memcg, false); |
df878fb0 KH |
5081 | } |
5082 | ||
8cdea7c0 BS |
5083 | static void mem_cgroup_destroy(struct cgroup_subsys *ss, |
5084 | struct cgroup *cont) | |
5085 | { | |
c0ff4b85 | 5086 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
c268e994 | 5087 | |
d1a4c0b3 GC |
5088 | kmem_cgroup_destroy(ss, cont); |
5089 | ||
c0ff4b85 | 5090 | mem_cgroup_put(memcg); |
8cdea7c0 BS |
5091 | } |
5092 | ||
5093 | static int mem_cgroup_populate(struct cgroup_subsys *ss, | |
5094 | struct cgroup *cont) | |
5095 | { | |
8c7c6e34 KH |
5096 | int ret; |
5097 | ||
5098 | ret = cgroup_add_files(cont, ss, mem_cgroup_files, | |
5099 | ARRAY_SIZE(mem_cgroup_files)); | |
5100 | ||
5101 | if (!ret) | |
5102 | ret = register_memsw_files(cont, ss); | |
e5671dfa GC |
5103 | |
5104 | if (!ret) | |
5105 | ret = register_kmem_files(cont, ss); | |
5106 | ||
8c7c6e34 | 5107 | return ret; |
8cdea7c0 BS |
5108 | } |
5109 | ||
02491447 | 5110 | #ifdef CONFIG_MMU |
7dc74be0 | 5111 | /* Handlers for move charge at task migration. */ |
854ffa8d DN |
5112 | #define PRECHARGE_COUNT_AT_ONCE 256 |
5113 | static int mem_cgroup_do_precharge(unsigned long count) | |
7dc74be0 | 5114 | { |
854ffa8d DN |
5115 | int ret = 0; |
5116 | int batch_count = PRECHARGE_COUNT_AT_ONCE; | |
c0ff4b85 | 5117 | struct mem_cgroup *memcg = mc.to; |
4ffef5fe | 5118 | |
c0ff4b85 | 5119 | if (mem_cgroup_is_root(memcg)) { |
854ffa8d DN |
5120 | mc.precharge += count; |
5121 | /* we don't need css_get for root */ | |
5122 | return ret; | |
5123 | } | |
5124 | /* try to charge at once */ | |
5125 | if (count > 1) { | |
5126 | struct res_counter *dummy; | |
5127 | /* | |
c0ff4b85 | 5128 | * "memcg" cannot be under rmdir() because we've already checked |
854ffa8d DN |
5129 | * by cgroup_lock_live_cgroup() that it is not removed and we |
5130 | * are still under the same cgroup_mutex. So we can postpone | |
5131 | * css_get(). | |
5132 | */ | |
c0ff4b85 | 5133 | if (res_counter_charge(&memcg->res, PAGE_SIZE * count, &dummy)) |
854ffa8d | 5134 | goto one_by_one; |
c0ff4b85 | 5135 | if (do_swap_account && res_counter_charge(&memcg->memsw, |
854ffa8d | 5136 | PAGE_SIZE * count, &dummy)) { |
c0ff4b85 | 5137 | res_counter_uncharge(&memcg->res, PAGE_SIZE * count); |
854ffa8d DN |
5138 | goto one_by_one; |
5139 | } | |
5140 | mc.precharge += count; | |
854ffa8d DN |
5141 | return ret; |
5142 | } | |
5143 | one_by_one: | |
5144 | /* fall back to one by one charge */ | |
5145 | while (count--) { | |
5146 | if (signal_pending(current)) { | |
5147 | ret = -EINTR; | |
5148 | break; | |
5149 | } | |
5150 | if (!batch_count--) { | |
5151 | batch_count = PRECHARGE_COUNT_AT_ONCE; | |
5152 | cond_resched(); | |
5153 | } | |
c0ff4b85 R |
5154 | ret = __mem_cgroup_try_charge(NULL, |
5155 | GFP_KERNEL, 1, &memcg, false); | |
5156 | if (ret || !memcg) | |
854ffa8d DN |
5157 | /* mem_cgroup_clear_mc() will do uncharge later */ |
5158 | return -ENOMEM; | |
5159 | mc.precharge++; | |
5160 | } | |
4ffef5fe DN |
5161 | return ret; |
5162 | } | |
5163 | ||
5164 | /** | |
5165 | * is_target_pte_for_mc - check a pte whether it is valid for move charge | |
5166 | * @vma: the vma the pte to be checked belongs | |
5167 | * @addr: the address corresponding to the pte to be checked | |
5168 | * @ptent: the pte to be checked | |
02491447 | 5169 | * @target: the pointer the target page or swap ent will be stored(can be NULL) |
4ffef5fe DN |
5170 | * |
5171 | * Returns | |
5172 | * 0(MC_TARGET_NONE): if the pte is not a target for move charge. | |
5173 | * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for | |
5174 | * move charge. if @target is not NULL, the page is stored in target->page | |
5175 | * with extra refcnt got(Callers should handle it). | |
02491447 DN |
5176 | * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a |
5177 | * target for charge migration. if @target is not NULL, the entry is stored | |
5178 | * in target->ent. | |
4ffef5fe DN |
5179 | * |
5180 | * Called with pte lock held. | |
5181 | */ | |
4ffef5fe DN |
5182 | union mc_target { |
5183 | struct page *page; | |
02491447 | 5184 | swp_entry_t ent; |
4ffef5fe DN |
5185 | }; |
5186 | ||
4ffef5fe DN |
5187 | enum mc_target_type { |
5188 | MC_TARGET_NONE, /* not used */ | |
5189 | MC_TARGET_PAGE, | |
02491447 | 5190 | MC_TARGET_SWAP, |
4ffef5fe DN |
5191 | }; |
5192 | ||
90254a65 DN |
5193 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
5194 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 5195 | { |
90254a65 | 5196 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 5197 | |
90254a65 DN |
5198 | if (!page || !page_mapped(page)) |
5199 | return NULL; | |
5200 | if (PageAnon(page)) { | |
5201 | /* we don't move shared anon */ | |
5202 | if (!move_anon() || page_mapcount(page) > 2) | |
5203 | return NULL; | |
87946a72 DN |
5204 | } else if (!move_file()) |
5205 | /* we ignore mapcount for file pages */ | |
90254a65 DN |
5206 | return NULL; |
5207 | if (!get_page_unless_zero(page)) | |
5208 | return NULL; | |
5209 | ||
5210 | return page; | |
5211 | } | |
5212 | ||
5213 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
5214 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5215 | { | |
5216 | int usage_count; | |
5217 | struct page *page = NULL; | |
5218 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
5219 | ||
5220 | if (!move_anon() || non_swap_entry(ent)) | |
5221 | return NULL; | |
5222 | usage_count = mem_cgroup_count_swap_user(ent, &page); | |
5223 | if (usage_count > 1) { /* we don't move shared anon */ | |
02491447 DN |
5224 | if (page) |
5225 | put_page(page); | |
90254a65 | 5226 | return NULL; |
02491447 | 5227 | } |
90254a65 DN |
5228 | if (do_swap_account) |
5229 | entry->val = ent.val; | |
5230 | ||
5231 | return page; | |
5232 | } | |
5233 | ||
87946a72 DN |
5234 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
5235 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5236 | { | |
5237 | struct page *page = NULL; | |
5238 | struct inode *inode; | |
5239 | struct address_space *mapping; | |
5240 | pgoff_t pgoff; | |
5241 | ||
5242 | if (!vma->vm_file) /* anonymous vma */ | |
5243 | return NULL; | |
5244 | if (!move_file()) | |
5245 | return NULL; | |
5246 | ||
5247 | inode = vma->vm_file->f_path.dentry->d_inode; | |
5248 | mapping = vma->vm_file->f_mapping; | |
5249 | if (pte_none(ptent)) | |
5250 | pgoff = linear_page_index(vma, addr); | |
5251 | else /* pte_file(ptent) is true */ | |
5252 | pgoff = pte_to_pgoff(ptent); | |
5253 | ||
5254 | /* page is moved even if it's not RSS of this task(page-faulted). */ | |
aa3b1895 HD |
5255 | page = find_get_page(mapping, pgoff); |
5256 | ||
5257 | #ifdef CONFIG_SWAP | |
5258 | /* shmem/tmpfs may report page out on swap: account for that too. */ | |
5259 | if (radix_tree_exceptional_entry(page)) { | |
5260 | swp_entry_t swap = radix_to_swp_entry(page); | |
87946a72 | 5261 | if (do_swap_account) |
aa3b1895 HD |
5262 | *entry = swap; |
5263 | page = find_get_page(&swapper_space, swap.val); | |
87946a72 | 5264 | } |
aa3b1895 | 5265 | #endif |
87946a72 DN |
5266 | return page; |
5267 | } | |
5268 | ||
90254a65 DN |
5269 | static int is_target_pte_for_mc(struct vm_area_struct *vma, |
5270 | unsigned long addr, pte_t ptent, union mc_target *target) | |
5271 | { | |
5272 | struct page *page = NULL; | |
5273 | struct page_cgroup *pc; | |
5274 | int ret = 0; | |
5275 | swp_entry_t ent = { .val = 0 }; | |
5276 | ||
5277 | if (pte_present(ptent)) | |
5278 | page = mc_handle_present_pte(vma, addr, ptent); | |
5279 | else if (is_swap_pte(ptent)) | |
5280 | page = mc_handle_swap_pte(vma, addr, ptent, &ent); | |
87946a72 DN |
5281 | else if (pte_none(ptent) || pte_file(ptent)) |
5282 | page = mc_handle_file_pte(vma, addr, ptent, &ent); | |
90254a65 DN |
5283 | |
5284 | if (!page && !ent.val) | |
5285 | return 0; | |
02491447 DN |
5286 | if (page) { |
5287 | pc = lookup_page_cgroup(page); | |
5288 | /* | |
5289 | * Do only loose check w/o page_cgroup lock. | |
5290 | * mem_cgroup_move_account() checks the pc is valid or not under | |
5291 | * the lock. | |
5292 | */ | |
5293 | if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { | |
5294 | ret = MC_TARGET_PAGE; | |
5295 | if (target) | |
5296 | target->page = page; | |
5297 | } | |
5298 | if (!ret || !target) | |
5299 | put_page(page); | |
5300 | } | |
90254a65 DN |
5301 | /* There is a swap entry and a page doesn't exist or isn't charged */ |
5302 | if (ent.val && !ret && | |
7f0f1546 KH |
5303 | css_id(&mc.from->css) == lookup_swap_cgroup(ent)) { |
5304 | ret = MC_TARGET_SWAP; | |
5305 | if (target) | |
5306 | target->ent = ent; | |
4ffef5fe | 5307 | } |
4ffef5fe DN |
5308 | return ret; |
5309 | } | |
5310 | ||
5311 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, | |
5312 | unsigned long addr, unsigned long end, | |
5313 | struct mm_walk *walk) | |
5314 | { | |
5315 | struct vm_area_struct *vma = walk->private; | |
5316 | pte_t *pte; | |
5317 | spinlock_t *ptl; | |
5318 | ||
03319327 DH |
5319 | split_huge_page_pmd(walk->mm, pmd); |
5320 | ||
4ffef5fe DN |
5321 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
5322 | for (; addr != end; pte++, addr += PAGE_SIZE) | |
5323 | if (is_target_pte_for_mc(vma, addr, *pte, NULL)) | |
5324 | mc.precharge++; /* increment precharge temporarily */ | |
5325 | pte_unmap_unlock(pte - 1, ptl); | |
5326 | cond_resched(); | |
5327 | ||
7dc74be0 DN |
5328 | return 0; |
5329 | } | |
5330 | ||
4ffef5fe DN |
5331 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
5332 | { | |
5333 | unsigned long precharge; | |
5334 | struct vm_area_struct *vma; | |
5335 | ||
dfe076b0 | 5336 | down_read(&mm->mmap_sem); |
4ffef5fe DN |
5337 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5338 | struct mm_walk mem_cgroup_count_precharge_walk = { | |
5339 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
5340 | .mm = mm, | |
5341 | .private = vma, | |
5342 | }; | |
5343 | if (is_vm_hugetlb_page(vma)) | |
5344 | continue; | |
4ffef5fe DN |
5345 | walk_page_range(vma->vm_start, vma->vm_end, |
5346 | &mem_cgroup_count_precharge_walk); | |
5347 | } | |
dfe076b0 | 5348 | up_read(&mm->mmap_sem); |
4ffef5fe DN |
5349 | |
5350 | precharge = mc.precharge; | |
5351 | mc.precharge = 0; | |
5352 | ||
5353 | return precharge; | |
5354 | } | |
5355 | ||
4ffef5fe DN |
5356 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
5357 | { | |
dfe076b0 DN |
5358 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
5359 | ||
5360 | VM_BUG_ON(mc.moving_task); | |
5361 | mc.moving_task = current; | |
5362 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
5363 | } |
5364 | ||
dfe076b0 DN |
5365 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
5366 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 5367 | { |
2bd9bb20 KH |
5368 | struct mem_cgroup *from = mc.from; |
5369 | struct mem_cgroup *to = mc.to; | |
5370 | ||
4ffef5fe | 5371 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d DN |
5372 | if (mc.precharge) { |
5373 | __mem_cgroup_cancel_charge(mc.to, mc.precharge); | |
5374 | mc.precharge = 0; | |
5375 | } | |
5376 | /* | |
5377 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
5378 | * we must uncharge here. | |
5379 | */ | |
5380 | if (mc.moved_charge) { | |
5381 | __mem_cgroup_cancel_charge(mc.from, mc.moved_charge); | |
5382 | mc.moved_charge = 0; | |
4ffef5fe | 5383 | } |
483c30b5 DN |
5384 | /* we must fixup refcnts and charges */ |
5385 | if (mc.moved_swap) { | |
483c30b5 DN |
5386 | /* uncharge swap account from the old cgroup */ |
5387 | if (!mem_cgroup_is_root(mc.from)) | |
5388 | res_counter_uncharge(&mc.from->memsw, | |
5389 | PAGE_SIZE * mc.moved_swap); | |
5390 | __mem_cgroup_put(mc.from, mc.moved_swap); | |
5391 | ||
5392 | if (!mem_cgroup_is_root(mc.to)) { | |
5393 | /* | |
5394 | * we charged both to->res and to->memsw, so we should | |
5395 | * uncharge to->res. | |
5396 | */ | |
5397 | res_counter_uncharge(&mc.to->res, | |
5398 | PAGE_SIZE * mc.moved_swap); | |
483c30b5 DN |
5399 | } |
5400 | /* we've already done mem_cgroup_get(mc.to) */ | |
483c30b5 DN |
5401 | mc.moved_swap = 0; |
5402 | } | |
dfe076b0 DN |
5403 | memcg_oom_recover(from); |
5404 | memcg_oom_recover(to); | |
5405 | wake_up_all(&mc.waitq); | |
5406 | } | |
5407 | ||
5408 | static void mem_cgroup_clear_mc(void) | |
5409 | { | |
5410 | struct mem_cgroup *from = mc.from; | |
5411 | ||
5412 | /* | |
5413 | * we must clear moving_task before waking up waiters at the end of | |
5414 | * task migration. | |
5415 | */ | |
5416 | mc.moving_task = NULL; | |
5417 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 5418 | spin_lock(&mc.lock); |
4ffef5fe DN |
5419 | mc.from = NULL; |
5420 | mc.to = NULL; | |
2bd9bb20 | 5421 | spin_unlock(&mc.lock); |
32047e2a | 5422 | mem_cgroup_end_move(from); |
4ffef5fe DN |
5423 | } |
5424 | ||
7dc74be0 DN |
5425 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, |
5426 | struct cgroup *cgroup, | |
2f7ee569 | 5427 | struct cgroup_taskset *tset) |
7dc74be0 | 5428 | { |
2f7ee569 | 5429 | struct task_struct *p = cgroup_taskset_first(tset); |
7dc74be0 | 5430 | int ret = 0; |
c0ff4b85 | 5431 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgroup); |
7dc74be0 | 5432 | |
c0ff4b85 | 5433 | if (memcg->move_charge_at_immigrate) { |
7dc74be0 DN |
5434 | struct mm_struct *mm; |
5435 | struct mem_cgroup *from = mem_cgroup_from_task(p); | |
5436 | ||
c0ff4b85 | 5437 | VM_BUG_ON(from == memcg); |
7dc74be0 DN |
5438 | |
5439 | mm = get_task_mm(p); | |
5440 | if (!mm) | |
5441 | return 0; | |
7dc74be0 | 5442 | /* We move charges only when we move a owner of the mm */ |
4ffef5fe DN |
5443 | if (mm->owner == p) { |
5444 | VM_BUG_ON(mc.from); | |
5445 | VM_BUG_ON(mc.to); | |
5446 | VM_BUG_ON(mc.precharge); | |
854ffa8d | 5447 | VM_BUG_ON(mc.moved_charge); |
483c30b5 | 5448 | VM_BUG_ON(mc.moved_swap); |
32047e2a | 5449 | mem_cgroup_start_move(from); |
2bd9bb20 | 5450 | spin_lock(&mc.lock); |
4ffef5fe | 5451 | mc.from = from; |
c0ff4b85 | 5452 | mc.to = memcg; |
2bd9bb20 | 5453 | spin_unlock(&mc.lock); |
dfe076b0 | 5454 | /* We set mc.moving_task later */ |
4ffef5fe DN |
5455 | |
5456 | ret = mem_cgroup_precharge_mc(mm); | |
5457 | if (ret) | |
5458 | mem_cgroup_clear_mc(); | |
dfe076b0 DN |
5459 | } |
5460 | mmput(mm); | |
7dc74be0 DN |
5461 | } |
5462 | return ret; | |
5463 | } | |
5464 | ||
5465 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, | |
5466 | struct cgroup *cgroup, | |
2f7ee569 | 5467 | struct cgroup_taskset *tset) |
7dc74be0 | 5468 | { |
4ffef5fe | 5469 | mem_cgroup_clear_mc(); |
7dc74be0 DN |
5470 | } |
5471 | ||
4ffef5fe DN |
5472 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
5473 | unsigned long addr, unsigned long end, | |
5474 | struct mm_walk *walk) | |
7dc74be0 | 5475 | { |
4ffef5fe DN |
5476 | int ret = 0; |
5477 | struct vm_area_struct *vma = walk->private; | |
5478 | pte_t *pte; | |
5479 | spinlock_t *ptl; | |
5480 | ||
03319327 | 5481 | split_huge_page_pmd(walk->mm, pmd); |
4ffef5fe DN |
5482 | retry: |
5483 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
5484 | for (; addr != end; addr += PAGE_SIZE) { | |
5485 | pte_t ptent = *(pte++); | |
5486 | union mc_target target; | |
5487 | int type; | |
5488 | struct page *page; | |
5489 | struct page_cgroup *pc; | |
02491447 | 5490 | swp_entry_t ent; |
4ffef5fe DN |
5491 | |
5492 | if (!mc.precharge) | |
5493 | break; | |
5494 | ||
5495 | type = is_target_pte_for_mc(vma, addr, ptent, &target); | |
5496 | switch (type) { | |
5497 | case MC_TARGET_PAGE: | |
5498 | page = target.page; | |
5499 | if (isolate_lru_page(page)) | |
5500 | goto put; | |
5501 | pc = lookup_page_cgroup(page); | |
7ec99d62 JW |
5502 | if (!mem_cgroup_move_account(page, 1, pc, |
5503 | mc.from, mc.to, false)) { | |
4ffef5fe | 5504 | mc.precharge--; |
854ffa8d DN |
5505 | /* we uncharge from mc.from later. */ |
5506 | mc.moved_charge++; | |
4ffef5fe DN |
5507 | } |
5508 | putback_lru_page(page); | |
5509 | put: /* is_target_pte_for_mc() gets the page */ | |
5510 | put_page(page); | |
5511 | break; | |
02491447 DN |
5512 | case MC_TARGET_SWAP: |
5513 | ent = target.ent; | |
483c30b5 DN |
5514 | if (!mem_cgroup_move_swap_account(ent, |
5515 | mc.from, mc.to, false)) { | |
02491447 | 5516 | mc.precharge--; |
483c30b5 DN |
5517 | /* we fixup refcnts and charges later. */ |
5518 | mc.moved_swap++; | |
5519 | } | |
02491447 | 5520 | break; |
4ffef5fe DN |
5521 | default: |
5522 | break; | |
5523 | } | |
5524 | } | |
5525 | pte_unmap_unlock(pte - 1, ptl); | |
5526 | cond_resched(); | |
5527 | ||
5528 | if (addr != end) { | |
5529 | /* | |
5530 | * We have consumed all precharges we got in can_attach(). | |
5531 | * We try charge one by one, but don't do any additional | |
5532 | * charges to mc.to if we have failed in charge once in attach() | |
5533 | * phase. | |
5534 | */ | |
854ffa8d | 5535 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
5536 | if (!ret) |
5537 | goto retry; | |
5538 | } | |
5539 | ||
5540 | return ret; | |
5541 | } | |
5542 | ||
5543 | static void mem_cgroup_move_charge(struct mm_struct *mm) | |
5544 | { | |
5545 | struct vm_area_struct *vma; | |
5546 | ||
5547 | lru_add_drain_all(); | |
dfe076b0 DN |
5548 | retry: |
5549 | if (unlikely(!down_read_trylock(&mm->mmap_sem))) { | |
5550 | /* | |
5551 | * Someone who are holding the mmap_sem might be waiting in | |
5552 | * waitq. So we cancel all extra charges, wake up all waiters, | |
5553 | * and retry. Because we cancel precharges, we might not be able | |
5554 | * to move enough charges, but moving charge is a best-effort | |
5555 | * feature anyway, so it wouldn't be a big problem. | |
5556 | */ | |
5557 | __mem_cgroup_clear_mc(); | |
5558 | cond_resched(); | |
5559 | goto retry; | |
5560 | } | |
4ffef5fe DN |
5561 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5562 | int ret; | |
5563 | struct mm_walk mem_cgroup_move_charge_walk = { | |
5564 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
5565 | .mm = mm, | |
5566 | .private = vma, | |
5567 | }; | |
5568 | if (is_vm_hugetlb_page(vma)) | |
5569 | continue; | |
4ffef5fe DN |
5570 | ret = walk_page_range(vma->vm_start, vma->vm_end, |
5571 | &mem_cgroup_move_charge_walk); | |
5572 | if (ret) | |
5573 | /* | |
5574 | * means we have consumed all precharges and failed in | |
5575 | * doing additional charge. Just abandon here. | |
5576 | */ | |
5577 | break; | |
5578 | } | |
dfe076b0 | 5579 | up_read(&mm->mmap_sem); |
7dc74be0 DN |
5580 | } |
5581 | ||
67e465a7 BS |
5582 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, |
5583 | struct cgroup *cont, | |
2f7ee569 | 5584 | struct cgroup_taskset *tset) |
67e465a7 | 5585 | { |
2f7ee569 | 5586 | struct task_struct *p = cgroup_taskset_first(tset); |
a433658c | 5587 | struct mm_struct *mm = get_task_mm(p); |
dfe076b0 | 5588 | |
dfe076b0 | 5589 | if (mm) { |
a433658c KM |
5590 | if (mc.to) |
5591 | mem_cgroup_move_charge(mm); | |
5592 | put_swap_token(mm); | |
dfe076b0 DN |
5593 | mmput(mm); |
5594 | } | |
a433658c KM |
5595 | if (mc.to) |
5596 | mem_cgroup_clear_mc(); | |
67e465a7 | 5597 | } |
5cfb80a7 DN |
5598 | #else /* !CONFIG_MMU */ |
5599 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, | |
5600 | struct cgroup *cgroup, | |
2f7ee569 | 5601 | struct cgroup_taskset *tset) |
5cfb80a7 DN |
5602 | { |
5603 | return 0; | |
5604 | } | |
5605 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, | |
5606 | struct cgroup *cgroup, | |
2f7ee569 | 5607 | struct cgroup_taskset *tset) |
5cfb80a7 DN |
5608 | { |
5609 | } | |
5610 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, | |
5611 | struct cgroup *cont, | |
2f7ee569 | 5612 | struct cgroup_taskset *tset) |
5cfb80a7 DN |
5613 | { |
5614 | } | |
5615 | #endif | |
67e465a7 | 5616 | |
8cdea7c0 BS |
5617 | struct cgroup_subsys mem_cgroup_subsys = { |
5618 | .name = "memory", | |
5619 | .subsys_id = mem_cgroup_subsys_id, | |
5620 | .create = mem_cgroup_create, | |
df878fb0 | 5621 | .pre_destroy = mem_cgroup_pre_destroy, |
8cdea7c0 BS |
5622 | .destroy = mem_cgroup_destroy, |
5623 | .populate = mem_cgroup_populate, | |
7dc74be0 DN |
5624 | .can_attach = mem_cgroup_can_attach, |
5625 | .cancel_attach = mem_cgroup_cancel_attach, | |
67e465a7 | 5626 | .attach = mem_cgroup_move_task, |
6d12e2d8 | 5627 | .early_init = 0, |
04046e1a | 5628 | .use_id = 1, |
8cdea7c0 | 5629 | }; |
c077719b KH |
5630 | |
5631 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
a42c390c MH |
5632 | static int __init enable_swap_account(char *s) |
5633 | { | |
5634 | /* consider enabled if no parameter or 1 is given */ | |
a2c8990a | 5635 | if (!strcmp(s, "1")) |
a42c390c | 5636 | really_do_swap_account = 1; |
a2c8990a | 5637 | else if (!strcmp(s, "0")) |
a42c390c MH |
5638 | really_do_swap_account = 0; |
5639 | return 1; | |
5640 | } | |
a2c8990a | 5641 | __setup("swapaccount=", enable_swap_account); |
c077719b | 5642 | |
c077719b | 5643 | #endif |