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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> |
8c7c6e34 | 36 | #include <linux/mutex.h> |
f64c3f54 | 37 | #include <linux/rbtree.h> |
b6ac57d5 | 38 | #include <linux/slab.h> |
66e1707b | 39 | #include <linux/swap.h> |
02491447 | 40 | #include <linux/swapops.h> |
66e1707b | 41 | #include <linux/spinlock.h> |
2e72b634 KS |
42 | #include <linux/eventfd.h> |
43 | #include <linux/sort.h> | |
66e1707b | 44 | #include <linux/fs.h> |
d2ceb9b7 | 45 | #include <linux/seq_file.h> |
33327948 | 46 | #include <linux/vmalloc.h> |
b69408e8 | 47 | #include <linux/mm_inline.h> |
52d4b9ac | 48 | #include <linux/page_cgroup.h> |
cdec2e42 | 49 | #include <linux/cpu.h> |
158e0a2d | 50 | #include <linux/oom.h> |
08e552c6 | 51 | #include "internal.h" |
8cdea7c0 | 52 | |
8697d331 BS |
53 | #include <asm/uaccess.h> |
54 | ||
cc8e970c KM |
55 | #include <trace/events/vmscan.h> |
56 | ||
a181b0e8 | 57 | struct cgroup_subsys mem_cgroup_subsys __read_mostly; |
a181b0e8 | 58 | #define MEM_CGROUP_RECLAIM_RETRIES 5 |
4b3bde4c | 59 | struct mem_cgroup *root_mem_cgroup __read_mostly; |
8cdea7c0 | 60 | |
c077719b | 61 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
338c8431 | 62 | /* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */ |
c077719b | 63 | int do_swap_account __read_mostly; |
a42c390c MH |
64 | |
65 | /* for remember boot option*/ | |
66 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED | |
67 | static int really_do_swap_account __initdata = 1; | |
68 | #else | |
69 | static int really_do_swap_account __initdata = 0; | |
70 | #endif | |
71 | ||
c077719b KH |
72 | #else |
73 | #define do_swap_account (0) | |
74 | #endif | |
75 | ||
76 | ||
d52aa412 KH |
77 | /* |
78 | * Statistics for memory cgroup. | |
79 | */ | |
80 | enum mem_cgroup_stat_index { | |
81 | /* | |
82 | * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss. | |
83 | */ | |
84 | MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */ | |
d69b042f | 85 | MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */ |
d8046582 | 86 | MEM_CGROUP_STAT_FILE_MAPPED, /* # of pages charged as file rss */ |
0c3e73e8 | 87 | MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */ |
711d3d2c | 88 | MEM_CGROUP_STAT_DATA, /* end of data requires synchronization */ |
32047e2a | 89 | MEM_CGROUP_ON_MOVE, /* someone is moving account between groups */ |
d52aa412 KH |
90 | MEM_CGROUP_STAT_NSTATS, |
91 | }; | |
92 | ||
e9f8974f JW |
93 | enum mem_cgroup_events_index { |
94 | MEM_CGROUP_EVENTS_PGPGIN, /* # of pages paged in */ | |
95 | MEM_CGROUP_EVENTS_PGPGOUT, /* # of pages paged out */ | |
96 | MEM_CGROUP_EVENTS_COUNT, /* # of pages paged in/out */ | |
456f998e YH |
97 | MEM_CGROUP_EVENTS_PGFAULT, /* # of page-faults */ |
98 | MEM_CGROUP_EVENTS_PGMAJFAULT, /* # of major page-faults */ | |
e9f8974f JW |
99 | MEM_CGROUP_EVENTS_NSTATS, |
100 | }; | |
7a159cc9 JW |
101 | /* |
102 | * Per memcg event counter is incremented at every pagein/pageout. With THP, | |
103 | * it will be incremated by the number of pages. This counter is used for | |
104 | * for trigger some periodic events. This is straightforward and better | |
105 | * than using jiffies etc. to handle periodic memcg event. | |
106 | */ | |
107 | enum mem_cgroup_events_target { | |
108 | MEM_CGROUP_TARGET_THRESH, | |
109 | MEM_CGROUP_TARGET_SOFTLIMIT, | |
453a9bf3 | 110 | MEM_CGROUP_TARGET_NUMAINFO, |
7a159cc9 JW |
111 | MEM_CGROUP_NTARGETS, |
112 | }; | |
113 | #define THRESHOLDS_EVENTS_TARGET (128) | |
114 | #define SOFTLIMIT_EVENTS_TARGET (1024) | |
453a9bf3 | 115 | #define NUMAINFO_EVENTS_TARGET (1024) |
e9f8974f | 116 | |
d52aa412 | 117 | struct mem_cgroup_stat_cpu { |
7a159cc9 | 118 | long count[MEM_CGROUP_STAT_NSTATS]; |
e9f8974f | 119 | unsigned long events[MEM_CGROUP_EVENTS_NSTATS]; |
7a159cc9 | 120 | unsigned long targets[MEM_CGROUP_NTARGETS]; |
d52aa412 KH |
121 | }; |
122 | ||
6d12e2d8 KH |
123 | /* |
124 | * per-zone information in memory controller. | |
125 | */ | |
6d12e2d8 | 126 | struct mem_cgroup_per_zone { |
072c56c1 KH |
127 | /* |
128 | * spin_lock to protect the per cgroup LRU | |
129 | */ | |
b69408e8 CL |
130 | struct list_head lists[NR_LRU_LISTS]; |
131 | unsigned long count[NR_LRU_LISTS]; | |
3e2f41f1 KM |
132 | |
133 | struct zone_reclaim_stat reclaim_stat; | |
f64c3f54 BS |
134 | struct rb_node tree_node; /* RB tree node */ |
135 | unsigned long long usage_in_excess;/* Set to the value by which */ | |
136 | /* the soft limit is exceeded*/ | |
137 | bool on_tree; | |
4e416953 BS |
138 | struct mem_cgroup *mem; /* Back pointer, we cannot */ |
139 | /* use container_of */ | |
6d12e2d8 KH |
140 | }; |
141 | /* Macro for accessing counter */ | |
142 | #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)]) | |
143 | ||
144 | struct mem_cgroup_per_node { | |
145 | struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES]; | |
146 | }; | |
147 | ||
148 | struct mem_cgroup_lru_info { | |
149 | struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES]; | |
150 | }; | |
151 | ||
f64c3f54 BS |
152 | /* |
153 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
154 | * their hierarchy representation | |
155 | */ | |
156 | ||
157 | struct mem_cgroup_tree_per_zone { | |
158 | struct rb_root rb_root; | |
159 | spinlock_t lock; | |
160 | }; | |
161 | ||
162 | struct mem_cgroup_tree_per_node { | |
163 | struct mem_cgroup_tree_per_zone rb_tree_per_zone[MAX_NR_ZONES]; | |
164 | }; | |
165 | ||
166 | struct mem_cgroup_tree { | |
167 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
168 | }; | |
169 | ||
170 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
171 | ||
2e72b634 KS |
172 | struct mem_cgroup_threshold { |
173 | struct eventfd_ctx *eventfd; | |
174 | u64 threshold; | |
175 | }; | |
176 | ||
9490ff27 | 177 | /* For threshold */ |
2e72b634 KS |
178 | struct mem_cgroup_threshold_ary { |
179 | /* An array index points to threshold just below usage. */ | |
5407a562 | 180 | int current_threshold; |
2e72b634 KS |
181 | /* Size of entries[] */ |
182 | unsigned int size; | |
183 | /* Array of thresholds */ | |
184 | struct mem_cgroup_threshold entries[0]; | |
185 | }; | |
2c488db2 KS |
186 | |
187 | struct mem_cgroup_thresholds { | |
188 | /* Primary thresholds array */ | |
189 | struct mem_cgroup_threshold_ary *primary; | |
190 | /* | |
191 | * Spare threshold array. | |
192 | * This is needed to make mem_cgroup_unregister_event() "never fail". | |
193 | * It must be able to store at least primary->size - 1 entries. | |
194 | */ | |
195 | struct mem_cgroup_threshold_ary *spare; | |
196 | }; | |
197 | ||
9490ff27 KH |
198 | /* for OOM */ |
199 | struct mem_cgroup_eventfd_list { | |
200 | struct list_head list; | |
201 | struct eventfd_ctx *eventfd; | |
202 | }; | |
2e72b634 | 203 | |
2e72b634 | 204 | static void mem_cgroup_threshold(struct mem_cgroup *mem); |
9490ff27 | 205 | static void mem_cgroup_oom_notify(struct mem_cgroup *mem); |
2e72b634 | 206 | |
82f9d486 KH |
207 | enum { |
208 | SCAN_BY_LIMIT, | |
209 | SCAN_BY_SYSTEM, | |
210 | NR_SCAN_CONTEXT, | |
211 | SCAN_BY_SHRINK, /* not recorded now */ | |
212 | }; | |
213 | ||
214 | enum { | |
215 | SCAN, | |
216 | SCAN_ANON, | |
217 | SCAN_FILE, | |
218 | ROTATE, | |
219 | ROTATE_ANON, | |
220 | ROTATE_FILE, | |
221 | FREED, | |
222 | FREED_ANON, | |
223 | FREED_FILE, | |
224 | ELAPSED, | |
225 | NR_SCANSTATS, | |
226 | }; | |
227 | ||
228 | struct scanstat { | |
229 | spinlock_t lock; | |
230 | unsigned long stats[NR_SCAN_CONTEXT][NR_SCANSTATS]; | |
231 | unsigned long rootstats[NR_SCAN_CONTEXT][NR_SCANSTATS]; | |
232 | }; | |
233 | ||
234 | const char *scanstat_string[NR_SCANSTATS] = { | |
235 | "scanned_pages", | |
236 | "scanned_anon_pages", | |
237 | "scanned_file_pages", | |
238 | "rotated_pages", | |
239 | "rotated_anon_pages", | |
240 | "rotated_file_pages", | |
241 | "freed_pages", | |
242 | "freed_anon_pages", | |
243 | "freed_file_pages", | |
244 | "elapsed_ns", | |
245 | }; | |
246 | #define SCANSTAT_WORD_LIMIT "_by_limit" | |
247 | #define SCANSTAT_WORD_SYSTEM "_by_system" | |
248 | #define SCANSTAT_WORD_HIERARCHY "_under_hierarchy" | |
249 | ||
250 | ||
8cdea7c0 BS |
251 | /* |
252 | * The memory controller data structure. The memory controller controls both | |
253 | * page cache and RSS per cgroup. We would eventually like to provide | |
254 | * statistics based on the statistics developed by Rik Van Riel for clock-pro, | |
255 | * to help the administrator determine what knobs to tune. | |
256 | * | |
257 | * TODO: Add a water mark for the memory controller. Reclaim will begin when | |
8a9f3ccd BS |
258 | * we hit the water mark. May be even add a low water mark, such that |
259 | * no reclaim occurs from a cgroup at it's low water mark, this is | |
260 | * a feature that will be implemented much later in the future. | |
8cdea7c0 BS |
261 | */ |
262 | struct mem_cgroup { | |
263 | struct cgroup_subsys_state css; | |
264 | /* | |
265 | * the counter to account for memory usage | |
266 | */ | |
267 | struct res_counter res; | |
8c7c6e34 KH |
268 | /* |
269 | * the counter to account for mem+swap usage. | |
270 | */ | |
271 | struct res_counter memsw; | |
78fb7466 PE |
272 | /* |
273 | * Per cgroup active and inactive list, similar to the | |
274 | * per zone LRU lists. | |
78fb7466 | 275 | */ |
6d12e2d8 | 276 | struct mem_cgroup_lru_info info; |
6d61ef40 | 277 | /* |
af901ca1 | 278 | * While reclaiming in a hierarchy, we cache the last child we |
04046e1a | 279 | * reclaimed from. |
6d61ef40 | 280 | */ |
04046e1a | 281 | int last_scanned_child; |
889976db YH |
282 | int last_scanned_node; |
283 | #if MAX_NUMNODES > 1 | |
284 | nodemask_t scan_nodes; | |
453a9bf3 KH |
285 | atomic_t numainfo_events; |
286 | atomic_t numainfo_updating; | |
889976db | 287 | #endif |
18f59ea7 BS |
288 | /* |
289 | * Should the accounting and control be hierarchical, per subtree? | |
290 | */ | |
291 | bool use_hierarchy; | |
79dfdacc MH |
292 | |
293 | bool oom_lock; | |
294 | atomic_t under_oom; | |
295 | ||
8c7c6e34 | 296 | atomic_t refcnt; |
14797e23 | 297 | |
1f4c025b | 298 | int swappiness; |
3c11ecf4 KH |
299 | /* OOM-Killer disable */ |
300 | int oom_kill_disable; | |
a7885eb8 | 301 | |
22a668d7 KH |
302 | /* set when res.limit == memsw.limit */ |
303 | bool memsw_is_minimum; | |
304 | ||
2e72b634 KS |
305 | /* protect arrays of thresholds */ |
306 | struct mutex thresholds_lock; | |
307 | ||
308 | /* thresholds for memory usage. RCU-protected */ | |
2c488db2 | 309 | struct mem_cgroup_thresholds thresholds; |
907860ed | 310 | |
2e72b634 | 311 | /* thresholds for mem+swap usage. RCU-protected */ |
2c488db2 | 312 | struct mem_cgroup_thresholds memsw_thresholds; |
907860ed | 313 | |
9490ff27 KH |
314 | /* For oom notifier event fd */ |
315 | struct list_head oom_notify; | |
82f9d486 KH |
316 | /* For recording LRU-scan statistics */ |
317 | struct scanstat scanstat; | |
7dc74be0 DN |
318 | /* |
319 | * Should we move charges of a task when a task is moved into this | |
320 | * mem_cgroup ? And what type of charges should we move ? | |
321 | */ | |
322 | unsigned long move_charge_at_immigrate; | |
d52aa412 | 323 | /* |
c62b1a3b | 324 | * percpu counter. |
d52aa412 | 325 | */ |
c62b1a3b | 326 | struct mem_cgroup_stat_cpu *stat; |
711d3d2c KH |
327 | /* |
328 | * used when a cpu is offlined or other synchronizations | |
329 | * See mem_cgroup_read_stat(). | |
330 | */ | |
331 | struct mem_cgroup_stat_cpu nocpu_base; | |
332 | spinlock_t pcp_counter_lock; | |
8cdea7c0 BS |
333 | }; |
334 | ||
7dc74be0 DN |
335 | /* Stuffs for move charges at task migration. */ |
336 | /* | |
337 | * Types of charges to be moved. "move_charge_at_immitgrate" is treated as a | |
338 | * left-shifted bitmap of these types. | |
339 | */ | |
340 | enum move_type { | |
4ffef5fe | 341 | MOVE_CHARGE_TYPE_ANON, /* private anonymous page and swap of it */ |
87946a72 | 342 | MOVE_CHARGE_TYPE_FILE, /* file page(including tmpfs) and swap of it */ |
7dc74be0 DN |
343 | NR_MOVE_TYPE, |
344 | }; | |
345 | ||
4ffef5fe DN |
346 | /* "mc" and its members are protected by cgroup_mutex */ |
347 | static struct move_charge_struct { | |
b1dd693e | 348 | spinlock_t lock; /* for from, to */ |
4ffef5fe DN |
349 | struct mem_cgroup *from; |
350 | struct mem_cgroup *to; | |
351 | unsigned long precharge; | |
854ffa8d | 352 | unsigned long moved_charge; |
483c30b5 | 353 | unsigned long moved_swap; |
8033b97c DN |
354 | struct task_struct *moving_task; /* a task moving charges */ |
355 | wait_queue_head_t waitq; /* a waitq for other context */ | |
356 | } mc = { | |
2bd9bb20 | 357 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
358 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
359 | }; | |
4ffef5fe | 360 | |
90254a65 DN |
361 | static bool move_anon(void) |
362 | { | |
363 | return test_bit(MOVE_CHARGE_TYPE_ANON, | |
364 | &mc.to->move_charge_at_immigrate); | |
365 | } | |
366 | ||
87946a72 DN |
367 | static bool move_file(void) |
368 | { | |
369 | return test_bit(MOVE_CHARGE_TYPE_FILE, | |
370 | &mc.to->move_charge_at_immigrate); | |
371 | } | |
372 | ||
4e416953 BS |
373 | /* |
374 | * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft | |
375 | * limit reclaim to prevent infinite loops, if they ever occur. | |
376 | */ | |
377 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS (100) | |
378 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS (2) | |
379 | ||
217bc319 KH |
380 | enum charge_type { |
381 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, | |
382 | MEM_CGROUP_CHARGE_TYPE_MAPPED, | |
4f98a2fe | 383 | MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ |
c05555b5 | 384 | MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ |
d13d1443 | 385 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
8a9478ca | 386 | MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ |
c05555b5 KH |
387 | NR_CHARGE_TYPE, |
388 | }; | |
389 | ||
8c7c6e34 KH |
390 | /* for encoding cft->private value on file */ |
391 | #define _MEM (0) | |
392 | #define _MEMSWAP (1) | |
9490ff27 | 393 | #define _OOM_TYPE (2) |
8c7c6e34 KH |
394 | #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val)) |
395 | #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff) | |
396 | #define MEMFILE_ATTR(val) ((val) & 0xffff) | |
9490ff27 KH |
397 | /* Used for OOM nofiier */ |
398 | #define OOM_CONTROL (0) | |
8c7c6e34 | 399 | |
75822b44 BS |
400 | /* |
401 | * Reclaim flags for mem_cgroup_hierarchical_reclaim | |
402 | */ | |
403 | #define MEM_CGROUP_RECLAIM_NOSWAP_BIT 0x0 | |
404 | #define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT) | |
405 | #define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1 | |
406 | #define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT) | |
4e416953 BS |
407 | #define MEM_CGROUP_RECLAIM_SOFT_BIT 0x2 |
408 | #define MEM_CGROUP_RECLAIM_SOFT (1 << MEM_CGROUP_RECLAIM_SOFT_BIT) | |
75822b44 | 409 | |
8c7c6e34 KH |
410 | static void mem_cgroup_get(struct mem_cgroup *mem); |
411 | static void mem_cgroup_put(struct mem_cgroup *mem); | |
7bcc1bb1 | 412 | static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem); |
26fe6168 | 413 | static void drain_all_stock_async(struct mem_cgroup *mem); |
8c7c6e34 | 414 | |
f64c3f54 BS |
415 | static struct mem_cgroup_per_zone * |
416 | mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid) | |
417 | { | |
418 | return &mem->info.nodeinfo[nid]->zoneinfo[zid]; | |
419 | } | |
420 | ||
d324236b WF |
421 | struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *mem) |
422 | { | |
423 | return &mem->css; | |
424 | } | |
425 | ||
f64c3f54 | 426 | static struct mem_cgroup_per_zone * |
97a6c37b | 427 | page_cgroup_zoneinfo(struct mem_cgroup *mem, struct page *page) |
f64c3f54 | 428 | { |
97a6c37b JW |
429 | int nid = page_to_nid(page); |
430 | int zid = page_zonenum(page); | |
f64c3f54 | 431 | |
f64c3f54 BS |
432 | return mem_cgroup_zoneinfo(mem, nid, zid); |
433 | } | |
434 | ||
435 | static struct mem_cgroup_tree_per_zone * | |
436 | soft_limit_tree_node_zone(int nid, int zid) | |
437 | { | |
438 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
439 | } | |
440 | ||
441 | static struct mem_cgroup_tree_per_zone * | |
442 | soft_limit_tree_from_page(struct page *page) | |
443 | { | |
444 | int nid = page_to_nid(page); | |
445 | int zid = page_zonenum(page); | |
446 | ||
447 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
448 | } | |
449 | ||
450 | static void | |
4e416953 | 451 | __mem_cgroup_insert_exceeded(struct mem_cgroup *mem, |
f64c3f54 | 452 | struct mem_cgroup_per_zone *mz, |
ef8745c1 KH |
453 | struct mem_cgroup_tree_per_zone *mctz, |
454 | unsigned long long new_usage_in_excess) | |
f64c3f54 BS |
455 | { |
456 | struct rb_node **p = &mctz->rb_root.rb_node; | |
457 | struct rb_node *parent = NULL; | |
458 | struct mem_cgroup_per_zone *mz_node; | |
459 | ||
460 | if (mz->on_tree) | |
461 | return; | |
462 | ||
ef8745c1 KH |
463 | mz->usage_in_excess = new_usage_in_excess; |
464 | if (!mz->usage_in_excess) | |
465 | return; | |
f64c3f54 BS |
466 | while (*p) { |
467 | parent = *p; | |
468 | mz_node = rb_entry(parent, struct mem_cgroup_per_zone, | |
469 | tree_node); | |
470 | if (mz->usage_in_excess < mz_node->usage_in_excess) | |
471 | p = &(*p)->rb_left; | |
472 | /* | |
473 | * We can't avoid mem cgroups that are over their soft | |
474 | * limit by the same amount | |
475 | */ | |
476 | else if (mz->usage_in_excess >= mz_node->usage_in_excess) | |
477 | p = &(*p)->rb_right; | |
478 | } | |
479 | rb_link_node(&mz->tree_node, parent, p); | |
480 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
481 | mz->on_tree = true; | |
4e416953 BS |
482 | } |
483 | ||
484 | static void | |
485 | __mem_cgroup_remove_exceeded(struct mem_cgroup *mem, | |
486 | struct mem_cgroup_per_zone *mz, | |
487 | struct mem_cgroup_tree_per_zone *mctz) | |
488 | { | |
489 | if (!mz->on_tree) | |
490 | return; | |
491 | rb_erase(&mz->tree_node, &mctz->rb_root); | |
492 | mz->on_tree = false; | |
493 | } | |
494 | ||
f64c3f54 BS |
495 | static void |
496 | mem_cgroup_remove_exceeded(struct mem_cgroup *mem, | |
497 | struct mem_cgroup_per_zone *mz, | |
498 | struct mem_cgroup_tree_per_zone *mctz) | |
499 | { | |
500 | spin_lock(&mctz->lock); | |
4e416953 | 501 | __mem_cgroup_remove_exceeded(mem, mz, mctz); |
f64c3f54 BS |
502 | spin_unlock(&mctz->lock); |
503 | } | |
504 | ||
f64c3f54 BS |
505 | |
506 | static void mem_cgroup_update_tree(struct mem_cgroup *mem, struct page *page) | |
507 | { | |
ef8745c1 | 508 | unsigned long long excess; |
f64c3f54 BS |
509 | struct mem_cgroup_per_zone *mz; |
510 | struct mem_cgroup_tree_per_zone *mctz; | |
4e649152 KH |
511 | int nid = page_to_nid(page); |
512 | int zid = page_zonenum(page); | |
f64c3f54 BS |
513 | mctz = soft_limit_tree_from_page(page); |
514 | ||
515 | /* | |
4e649152 KH |
516 | * Necessary to update all ancestors when hierarchy is used. |
517 | * because their event counter is not touched. | |
f64c3f54 | 518 | */ |
4e649152 KH |
519 | for (; mem; mem = parent_mem_cgroup(mem)) { |
520 | mz = mem_cgroup_zoneinfo(mem, nid, zid); | |
ef8745c1 | 521 | excess = res_counter_soft_limit_excess(&mem->res); |
4e649152 KH |
522 | /* |
523 | * We have to update the tree if mz is on RB-tree or | |
524 | * mem is over its softlimit. | |
525 | */ | |
ef8745c1 | 526 | if (excess || mz->on_tree) { |
4e649152 KH |
527 | spin_lock(&mctz->lock); |
528 | /* if on-tree, remove it */ | |
529 | if (mz->on_tree) | |
530 | __mem_cgroup_remove_exceeded(mem, mz, mctz); | |
531 | /* | |
ef8745c1 KH |
532 | * Insert again. mz->usage_in_excess will be updated. |
533 | * If excess is 0, no tree ops. | |
4e649152 | 534 | */ |
ef8745c1 | 535 | __mem_cgroup_insert_exceeded(mem, mz, mctz, excess); |
4e649152 KH |
536 | spin_unlock(&mctz->lock); |
537 | } | |
f64c3f54 BS |
538 | } |
539 | } | |
540 | ||
541 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *mem) | |
542 | { | |
543 | int node, zone; | |
544 | struct mem_cgroup_per_zone *mz; | |
545 | struct mem_cgroup_tree_per_zone *mctz; | |
546 | ||
547 | for_each_node_state(node, N_POSSIBLE) { | |
548 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
549 | mz = mem_cgroup_zoneinfo(mem, node, zone); | |
550 | mctz = soft_limit_tree_node_zone(node, zone); | |
551 | mem_cgroup_remove_exceeded(mem, mz, mctz); | |
552 | } | |
553 | } | |
554 | } | |
555 | ||
4e416953 BS |
556 | static struct mem_cgroup_per_zone * |
557 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
558 | { | |
559 | struct rb_node *rightmost = NULL; | |
26251eaf | 560 | struct mem_cgroup_per_zone *mz; |
4e416953 BS |
561 | |
562 | retry: | |
26251eaf | 563 | mz = NULL; |
4e416953 BS |
564 | rightmost = rb_last(&mctz->rb_root); |
565 | if (!rightmost) | |
566 | goto done; /* Nothing to reclaim from */ | |
567 | ||
568 | mz = rb_entry(rightmost, struct mem_cgroup_per_zone, tree_node); | |
569 | /* | |
570 | * Remove the node now but someone else can add it back, | |
571 | * we will to add it back at the end of reclaim to its correct | |
572 | * position in the tree. | |
573 | */ | |
574 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); | |
575 | if (!res_counter_soft_limit_excess(&mz->mem->res) || | |
576 | !css_tryget(&mz->mem->css)) | |
577 | goto retry; | |
578 | done: | |
579 | return mz; | |
580 | } | |
581 | ||
582 | static struct mem_cgroup_per_zone * | |
583 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
584 | { | |
585 | struct mem_cgroup_per_zone *mz; | |
586 | ||
587 | spin_lock(&mctz->lock); | |
588 | mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
589 | spin_unlock(&mctz->lock); | |
590 | return mz; | |
591 | } | |
592 | ||
711d3d2c KH |
593 | /* |
594 | * Implementation Note: reading percpu statistics for memcg. | |
595 | * | |
596 | * Both of vmstat[] and percpu_counter has threshold and do periodic | |
597 | * synchronization to implement "quick" read. There are trade-off between | |
598 | * reading cost and precision of value. Then, we may have a chance to implement | |
599 | * a periodic synchronizion of counter in memcg's counter. | |
600 | * | |
601 | * But this _read() function is used for user interface now. The user accounts | |
602 | * memory usage by memory cgroup and he _always_ requires exact value because | |
603 | * he accounts memory. Even if we provide quick-and-fuzzy read, we always | |
604 | * have to visit all online cpus and make sum. So, for now, unnecessary | |
605 | * synchronization is not implemented. (just implemented for cpu hotplug) | |
606 | * | |
607 | * If there are kernel internal actions which can make use of some not-exact | |
608 | * value, and reading all cpu value can be performance bottleneck in some | |
609 | * common workload, threashold and synchonization as vmstat[] should be | |
610 | * implemented. | |
611 | */ | |
7a159cc9 JW |
612 | static long mem_cgroup_read_stat(struct mem_cgroup *mem, |
613 | enum mem_cgroup_stat_index idx) | |
c62b1a3b | 614 | { |
7a159cc9 | 615 | long val = 0; |
c62b1a3b | 616 | int cpu; |
c62b1a3b | 617 | |
711d3d2c KH |
618 | get_online_cpus(); |
619 | for_each_online_cpu(cpu) | |
c62b1a3b | 620 | val += per_cpu(mem->stat->count[idx], cpu); |
711d3d2c KH |
621 | #ifdef CONFIG_HOTPLUG_CPU |
622 | spin_lock(&mem->pcp_counter_lock); | |
623 | val += mem->nocpu_base.count[idx]; | |
624 | spin_unlock(&mem->pcp_counter_lock); | |
625 | #endif | |
626 | put_online_cpus(); | |
c62b1a3b KH |
627 | return val; |
628 | } | |
629 | ||
0c3e73e8 BS |
630 | static void mem_cgroup_swap_statistics(struct mem_cgroup *mem, |
631 | bool charge) | |
632 | { | |
633 | int val = (charge) ? 1 : -1; | |
c62b1a3b | 634 | this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_SWAPOUT], val); |
0c3e73e8 BS |
635 | } |
636 | ||
456f998e YH |
637 | void mem_cgroup_pgfault(struct mem_cgroup *mem, int val) |
638 | { | |
639 | this_cpu_add(mem->stat->events[MEM_CGROUP_EVENTS_PGFAULT], val); | |
640 | } | |
641 | ||
642 | void mem_cgroup_pgmajfault(struct mem_cgroup *mem, int val) | |
643 | { | |
644 | this_cpu_add(mem->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT], val); | |
645 | } | |
646 | ||
e9f8974f JW |
647 | static unsigned long mem_cgroup_read_events(struct mem_cgroup *mem, |
648 | enum mem_cgroup_events_index idx) | |
649 | { | |
650 | unsigned long val = 0; | |
651 | int cpu; | |
652 | ||
653 | for_each_online_cpu(cpu) | |
654 | val += per_cpu(mem->stat->events[idx], cpu); | |
655 | #ifdef CONFIG_HOTPLUG_CPU | |
656 | spin_lock(&mem->pcp_counter_lock); | |
657 | val += mem->nocpu_base.events[idx]; | |
658 | spin_unlock(&mem->pcp_counter_lock); | |
659 | #endif | |
660 | return val; | |
661 | } | |
662 | ||
c05555b5 | 663 | static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, |
e401f176 | 664 | bool file, int nr_pages) |
d52aa412 | 665 | { |
c62b1a3b KH |
666 | preempt_disable(); |
667 | ||
e401f176 KH |
668 | if (file) |
669 | __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_CACHE], nr_pages); | |
d52aa412 | 670 | else |
e401f176 | 671 | __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_RSS], nr_pages); |
55e462b0 | 672 | |
e401f176 KH |
673 | /* pagein of a big page is an event. So, ignore page size */ |
674 | if (nr_pages > 0) | |
e9f8974f | 675 | __this_cpu_inc(mem->stat->events[MEM_CGROUP_EVENTS_PGPGIN]); |
3751d604 | 676 | else { |
e9f8974f | 677 | __this_cpu_inc(mem->stat->events[MEM_CGROUP_EVENTS_PGPGOUT]); |
3751d604 KH |
678 | nr_pages = -nr_pages; /* for event */ |
679 | } | |
e401f176 | 680 | |
e9f8974f | 681 | __this_cpu_add(mem->stat->events[MEM_CGROUP_EVENTS_COUNT], nr_pages); |
2e72b634 | 682 | |
c62b1a3b | 683 | preempt_enable(); |
6d12e2d8 KH |
684 | } |
685 | ||
bb2a0de9 KH |
686 | unsigned long |
687 | mem_cgroup_zone_nr_lru_pages(struct mem_cgroup *mem, int nid, int zid, | |
688 | unsigned int lru_mask) | |
889976db YH |
689 | { |
690 | struct mem_cgroup_per_zone *mz; | |
bb2a0de9 KH |
691 | enum lru_list l; |
692 | unsigned long ret = 0; | |
693 | ||
694 | mz = mem_cgroup_zoneinfo(mem, nid, zid); | |
695 | ||
696 | for_each_lru(l) { | |
697 | if (BIT(l) & lru_mask) | |
698 | ret += MEM_CGROUP_ZSTAT(mz, l); | |
699 | } | |
700 | return ret; | |
701 | } | |
702 | ||
703 | static unsigned long | |
704 | mem_cgroup_node_nr_lru_pages(struct mem_cgroup *mem, | |
705 | int nid, unsigned int lru_mask) | |
706 | { | |
889976db YH |
707 | u64 total = 0; |
708 | int zid; | |
709 | ||
bb2a0de9 KH |
710 | for (zid = 0; zid < MAX_NR_ZONES; zid++) |
711 | total += mem_cgroup_zone_nr_lru_pages(mem, nid, zid, lru_mask); | |
712 | ||
889976db YH |
713 | return total; |
714 | } | |
bb2a0de9 KH |
715 | |
716 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *mem, | |
717 | unsigned int lru_mask) | |
6d12e2d8 | 718 | { |
889976db | 719 | int nid; |
6d12e2d8 KH |
720 | u64 total = 0; |
721 | ||
bb2a0de9 KH |
722 | for_each_node_state(nid, N_HIGH_MEMORY) |
723 | total += mem_cgroup_node_nr_lru_pages(mem, nid, lru_mask); | |
6d12e2d8 | 724 | return total; |
d52aa412 KH |
725 | } |
726 | ||
7a159cc9 JW |
727 | static bool __memcg_event_check(struct mem_cgroup *mem, int target) |
728 | { | |
729 | unsigned long val, next; | |
730 | ||
731 | val = this_cpu_read(mem->stat->events[MEM_CGROUP_EVENTS_COUNT]); | |
732 | next = this_cpu_read(mem->stat->targets[target]); | |
733 | /* from time_after() in jiffies.h */ | |
734 | return ((long)next - (long)val < 0); | |
735 | } | |
736 | ||
737 | static void __mem_cgroup_target_update(struct mem_cgroup *mem, int target) | |
d2265e6f | 738 | { |
7a159cc9 | 739 | unsigned long val, next; |
d2265e6f | 740 | |
e9f8974f | 741 | val = this_cpu_read(mem->stat->events[MEM_CGROUP_EVENTS_COUNT]); |
d2265e6f | 742 | |
7a159cc9 JW |
743 | switch (target) { |
744 | case MEM_CGROUP_TARGET_THRESH: | |
745 | next = val + THRESHOLDS_EVENTS_TARGET; | |
746 | break; | |
747 | case MEM_CGROUP_TARGET_SOFTLIMIT: | |
748 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
749 | break; | |
453a9bf3 KH |
750 | case MEM_CGROUP_TARGET_NUMAINFO: |
751 | next = val + NUMAINFO_EVENTS_TARGET; | |
752 | break; | |
7a159cc9 JW |
753 | default: |
754 | return; | |
755 | } | |
756 | ||
757 | this_cpu_write(mem->stat->targets[target], next); | |
d2265e6f KH |
758 | } |
759 | ||
760 | /* | |
761 | * Check events in order. | |
762 | * | |
763 | */ | |
764 | static void memcg_check_events(struct mem_cgroup *mem, struct page *page) | |
765 | { | |
766 | /* threshold event is triggered in finer grain than soft limit */ | |
7a159cc9 | 767 | if (unlikely(__memcg_event_check(mem, MEM_CGROUP_TARGET_THRESH))) { |
d2265e6f | 768 | mem_cgroup_threshold(mem); |
7a159cc9 JW |
769 | __mem_cgroup_target_update(mem, MEM_CGROUP_TARGET_THRESH); |
770 | if (unlikely(__memcg_event_check(mem, | |
453a9bf3 | 771 | MEM_CGROUP_TARGET_SOFTLIMIT))) { |
d2265e6f | 772 | mem_cgroup_update_tree(mem, page); |
7a159cc9 | 773 | __mem_cgroup_target_update(mem, |
453a9bf3 KH |
774 | MEM_CGROUP_TARGET_SOFTLIMIT); |
775 | } | |
776 | #if MAX_NUMNODES > 1 | |
777 | if (unlikely(__memcg_event_check(mem, | |
778 | MEM_CGROUP_TARGET_NUMAINFO))) { | |
779 | atomic_inc(&mem->numainfo_events); | |
780 | __mem_cgroup_target_update(mem, | |
781 | MEM_CGROUP_TARGET_NUMAINFO); | |
7a159cc9 | 782 | } |
453a9bf3 | 783 | #endif |
d2265e6f KH |
784 | } |
785 | } | |
786 | ||
d5b69e38 | 787 | static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) |
8cdea7c0 BS |
788 | { |
789 | return container_of(cgroup_subsys_state(cont, | |
790 | mem_cgroup_subsys_id), struct mem_cgroup, | |
791 | css); | |
792 | } | |
793 | ||
cf475ad2 | 794 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 795 | { |
31a78f23 BS |
796 | /* |
797 | * mm_update_next_owner() may clear mm->owner to NULL | |
798 | * if it races with swapoff, page migration, etc. | |
799 | * So this can be called with p == NULL. | |
800 | */ | |
801 | if (unlikely(!p)) | |
802 | return NULL; | |
803 | ||
78fb7466 PE |
804 | return container_of(task_subsys_state(p, mem_cgroup_subsys_id), |
805 | struct mem_cgroup, css); | |
806 | } | |
807 | ||
a433658c | 808 | struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) |
54595fe2 KH |
809 | { |
810 | struct mem_cgroup *mem = NULL; | |
0b7f569e KH |
811 | |
812 | if (!mm) | |
813 | return NULL; | |
54595fe2 KH |
814 | /* |
815 | * Because we have no locks, mm->owner's may be being moved to other | |
816 | * cgroup. We use css_tryget() here even if this looks | |
817 | * pessimistic (rather than adding locks here). | |
818 | */ | |
819 | rcu_read_lock(); | |
820 | do { | |
821 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
822 | if (unlikely(!mem)) | |
823 | break; | |
824 | } while (!css_tryget(&mem->css)); | |
825 | rcu_read_unlock(); | |
826 | return mem; | |
827 | } | |
828 | ||
7d74b06f KH |
829 | /* The caller has to guarantee "mem" exists before calling this */ |
830 | static struct mem_cgroup *mem_cgroup_start_loop(struct mem_cgroup *mem) | |
14067bb3 | 831 | { |
711d3d2c KH |
832 | struct cgroup_subsys_state *css; |
833 | int found; | |
834 | ||
835 | if (!mem) /* ROOT cgroup has the smallest ID */ | |
836 | return root_mem_cgroup; /*css_put/get against root is ignored*/ | |
837 | if (!mem->use_hierarchy) { | |
838 | if (css_tryget(&mem->css)) | |
839 | return mem; | |
840 | return NULL; | |
841 | } | |
842 | rcu_read_lock(); | |
843 | /* | |
844 | * searching a memory cgroup which has the smallest ID under given | |
845 | * ROOT cgroup. (ID >= 1) | |
846 | */ | |
847 | css = css_get_next(&mem_cgroup_subsys, 1, &mem->css, &found); | |
848 | if (css && css_tryget(css)) | |
849 | mem = container_of(css, struct mem_cgroup, css); | |
850 | else | |
851 | mem = NULL; | |
852 | rcu_read_unlock(); | |
853 | return mem; | |
7d74b06f KH |
854 | } |
855 | ||
856 | static struct mem_cgroup *mem_cgroup_get_next(struct mem_cgroup *iter, | |
857 | struct mem_cgroup *root, | |
858 | bool cond) | |
859 | { | |
860 | int nextid = css_id(&iter->css) + 1; | |
861 | int found; | |
862 | int hierarchy_used; | |
14067bb3 | 863 | struct cgroup_subsys_state *css; |
14067bb3 | 864 | |
7d74b06f | 865 | hierarchy_used = iter->use_hierarchy; |
14067bb3 | 866 | |
7d74b06f | 867 | css_put(&iter->css); |
711d3d2c KH |
868 | /* If no ROOT, walk all, ignore hierarchy */ |
869 | if (!cond || (root && !hierarchy_used)) | |
7d74b06f | 870 | return NULL; |
14067bb3 | 871 | |
711d3d2c KH |
872 | if (!root) |
873 | root = root_mem_cgroup; | |
874 | ||
7d74b06f KH |
875 | do { |
876 | iter = NULL; | |
14067bb3 | 877 | rcu_read_lock(); |
7d74b06f KH |
878 | |
879 | css = css_get_next(&mem_cgroup_subsys, nextid, | |
880 | &root->css, &found); | |
14067bb3 | 881 | if (css && css_tryget(css)) |
7d74b06f | 882 | iter = container_of(css, struct mem_cgroup, css); |
14067bb3 | 883 | rcu_read_unlock(); |
7d74b06f | 884 | /* If css is NULL, no more cgroups will be found */ |
14067bb3 | 885 | nextid = found + 1; |
7d74b06f | 886 | } while (css && !iter); |
14067bb3 | 887 | |
7d74b06f | 888 | return iter; |
14067bb3 | 889 | } |
7d74b06f KH |
890 | /* |
891 | * for_eacn_mem_cgroup_tree() for visiting all cgroup under tree. Please | |
892 | * be careful that "break" loop is not allowed. We have reference count. | |
893 | * Instead of that modify "cond" to be false and "continue" to exit the loop. | |
894 | */ | |
895 | #define for_each_mem_cgroup_tree_cond(iter, root, cond) \ | |
896 | for (iter = mem_cgroup_start_loop(root);\ | |
897 | iter != NULL;\ | |
898 | iter = mem_cgroup_get_next(iter, root, cond)) | |
899 | ||
900 | #define for_each_mem_cgroup_tree(iter, root) \ | |
901 | for_each_mem_cgroup_tree_cond(iter, root, true) | |
902 | ||
711d3d2c KH |
903 | #define for_each_mem_cgroup_all(iter) \ |
904 | for_each_mem_cgroup_tree_cond(iter, NULL, true) | |
905 | ||
14067bb3 | 906 | |
4b3bde4c BS |
907 | static inline bool mem_cgroup_is_root(struct mem_cgroup *mem) |
908 | { | |
909 | return (mem == root_mem_cgroup); | |
910 | } | |
911 | ||
456f998e YH |
912 | void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) |
913 | { | |
914 | struct mem_cgroup *mem; | |
915 | ||
916 | if (!mm) | |
917 | return; | |
918 | ||
919 | rcu_read_lock(); | |
920 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
921 | if (unlikely(!mem)) | |
922 | goto out; | |
923 | ||
924 | switch (idx) { | |
925 | case PGMAJFAULT: | |
926 | mem_cgroup_pgmajfault(mem, 1); | |
927 | break; | |
928 | case PGFAULT: | |
929 | mem_cgroup_pgfault(mem, 1); | |
930 | break; | |
931 | default: | |
932 | BUG(); | |
933 | } | |
934 | out: | |
935 | rcu_read_unlock(); | |
936 | } | |
937 | EXPORT_SYMBOL(mem_cgroup_count_vm_event); | |
938 | ||
08e552c6 KH |
939 | /* |
940 | * Following LRU functions are allowed to be used without PCG_LOCK. | |
941 | * Operations are called by routine of global LRU independently from memcg. | |
942 | * What we have to take care of here is validness of pc->mem_cgroup. | |
943 | * | |
944 | * Changes to pc->mem_cgroup happens when | |
945 | * 1. charge | |
946 | * 2. moving account | |
947 | * In typical case, "charge" is done before add-to-lru. Exception is SwapCache. | |
948 | * It is added to LRU before charge. | |
949 | * If PCG_USED bit is not set, page_cgroup is not added to this private LRU. | |
950 | * When moving account, the page is not on LRU. It's isolated. | |
951 | */ | |
4f98a2fe | 952 | |
08e552c6 KH |
953 | void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru) |
954 | { | |
955 | struct page_cgroup *pc; | |
08e552c6 | 956 | struct mem_cgroup_per_zone *mz; |
6d12e2d8 | 957 | |
f8d66542 | 958 | if (mem_cgroup_disabled()) |
08e552c6 KH |
959 | return; |
960 | pc = lookup_page_cgroup(page); | |
961 | /* can happen while we handle swapcache. */ | |
4b3bde4c | 962 | if (!TestClearPageCgroupAcctLRU(pc)) |
08e552c6 | 963 | return; |
4b3bde4c | 964 | VM_BUG_ON(!pc->mem_cgroup); |
544122e5 KH |
965 | /* |
966 | * We don't check PCG_USED bit. It's cleared when the "page" is finally | |
967 | * removed from global LRU. | |
968 | */ | |
97a6c37b | 969 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
ece35ca8 KH |
970 | /* huge page split is done under lru_lock. so, we have no races. */ |
971 | MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page); | |
4b3bde4c BS |
972 | if (mem_cgroup_is_root(pc->mem_cgroup)) |
973 | return; | |
974 | VM_BUG_ON(list_empty(&pc->lru)); | |
08e552c6 | 975 | list_del_init(&pc->lru); |
6d12e2d8 KH |
976 | } |
977 | ||
08e552c6 | 978 | void mem_cgroup_del_lru(struct page *page) |
6d12e2d8 | 979 | { |
08e552c6 KH |
980 | mem_cgroup_del_lru_list(page, page_lru(page)); |
981 | } | |
b69408e8 | 982 | |
3f58a829 MK |
983 | /* |
984 | * Writeback is about to end against a page which has been marked for immediate | |
985 | * reclaim. If it still appears to be reclaimable, move it to the tail of the | |
986 | * inactive list. | |
987 | */ | |
988 | void mem_cgroup_rotate_reclaimable_page(struct page *page) | |
989 | { | |
990 | struct mem_cgroup_per_zone *mz; | |
991 | struct page_cgroup *pc; | |
992 | enum lru_list lru = page_lru(page); | |
993 | ||
994 | if (mem_cgroup_disabled()) | |
995 | return; | |
996 | ||
997 | pc = lookup_page_cgroup(page); | |
998 | /* unused or root page is not rotated. */ | |
999 | if (!PageCgroupUsed(pc)) | |
1000 | return; | |
1001 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ | |
1002 | smp_rmb(); | |
1003 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
1004 | return; | |
97a6c37b | 1005 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
3f58a829 MK |
1006 | list_move_tail(&pc->lru, &mz->lists[lru]); |
1007 | } | |
1008 | ||
08e552c6 KH |
1009 | void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru) |
1010 | { | |
1011 | struct mem_cgroup_per_zone *mz; | |
1012 | struct page_cgroup *pc; | |
b69408e8 | 1013 | |
f8d66542 | 1014 | if (mem_cgroup_disabled()) |
08e552c6 | 1015 | return; |
6d12e2d8 | 1016 | |
08e552c6 | 1017 | pc = lookup_page_cgroup(page); |
4b3bde4c | 1018 | /* unused or root page is not rotated. */ |
713735b4 JW |
1019 | if (!PageCgroupUsed(pc)) |
1020 | return; | |
1021 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ | |
1022 | smp_rmb(); | |
1023 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
08e552c6 | 1024 | return; |
97a6c37b | 1025 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
08e552c6 | 1026 | list_move(&pc->lru, &mz->lists[lru]); |
6d12e2d8 KH |
1027 | } |
1028 | ||
08e552c6 | 1029 | void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru) |
66e1707b | 1030 | { |
08e552c6 KH |
1031 | struct page_cgroup *pc; |
1032 | struct mem_cgroup_per_zone *mz; | |
6d12e2d8 | 1033 | |
f8d66542 | 1034 | if (mem_cgroup_disabled()) |
08e552c6 KH |
1035 | return; |
1036 | pc = lookup_page_cgroup(page); | |
4b3bde4c | 1037 | VM_BUG_ON(PageCgroupAcctLRU(pc)); |
08e552c6 | 1038 | if (!PageCgroupUsed(pc)) |
894bc310 | 1039 | return; |
713735b4 JW |
1040 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
1041 | smp_rmb(); | |
97a6c37b | 1042 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
ece35ca8 KH |
1043 | /* huge page split is done under lru_lock. so, we have no races. */ |
1044 | MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page); | |
4b3bde4c BS |
1045 | SetPageCgroupAcctLRU(pc); |
1046 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
1047 | return; | |
08e552c6 KH |
1048 | list_add(&pc->lru, &mz->lists[lru]); |
1049 | } | |
544122e5 | 1050 | |
08e552c6 | 1051 | /* |
5a6475a4 KH |
1052 | * At handling SwapCache and other FUSE stuff, pc->mem_cgroup may be changed |
1053 | * while it's linked to lru because the page may be reused after it's fully | |
1054 | * uncharged. To handle that, unlink page_cgroup from LRU when charge it again. | |
1055 | * It's done under lock_page and expected that zone->lru_lock isnever held. | |
08e552c6 | 1056 | */ |
5a6475a4 | 1057 | static void mem_cgroup_lru_del_before_commit(struct page *page) |
08e552c6 | 1058 | { |
544122e5 KH |
1059 | unsigned long flags; |
1060 | struct zone *zone = page_zone(page); | |
1061 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
1062 | ||
5a6475a4 KH |
1063 | /* |
1064 | * Doing this check without taking ->lru_lock seems wrong but this | |
1065 | * is safe. Because if page_cgroup's USED bit is unset, the page | |
1066 | * will not be added to any memcg's LRU. If page_cgroup's USED bit is | |
1067 | * set, the commit after this will fail, anyway. | |
1068 | * This all charge/uncharge is done under some mutual execustion. | |
1069 | * So, we don't need to taking care of changes in USED bit. | |
1070 | */ | |
1071 | if (likely(!PageLRU(page))) | |
1072 | return; | |
1073 | ||
544122e5 KH |
1074 | spin_lock_irqsave(&zone->lru_lock, flags); |
1075 | /* | |
1076 | * Forget old LRU when this page_cgroup is *not* used. This Used bit | |
1077 | * is guarded by lock_page() because the page is SwapCache. | |
1078 | */ | |
1079 | if (!PageCgroupUsed(pc)) | |
1080 | mem_cgroup_del_lru_list(page, page_lru(page)); | |
1081 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
08e552c6 KH |
1082 | } |
1083 | ||
5a6475a4 | 1084 | static void mem_cgroup_lru_add_after_commit(struct page *page) |
544122e5 KH |
1085 | { |
1086 | unsigned long flags; | |
1087 | struct zone *zone = page_zone(page); | |
1088 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
1089 | ||
5a6475a4 KH |
1090 | /* taking care of that the page is added to LRU while we commit it */ |
1091 | if (likely(!PageLRU(page))) | |
1092 | return; | |
544122e5 KH |
1093 | spin_lock_irqsave(&zone->lru_lock, flags); |
1094 | /* link when the page is linked to LRU but page_cgroup isn't */ | |
4b3bde4c | 1095 | if (PageLRU(page) && !PageCgroupAcctLRU(pc)) |
544122e5 KH |
1096 | mem_cgroup_add_lru_list(page, page_lru(page)); |
1097 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
1098 | } | |
1099 | ||
1100 | ||
08e552c6 KH |
1101 | void mem_cgroup_move_lists(struct page *page, |
1102 | enum lru_list from, enum lru_list to) | |
1103 | { | |
f8d66542 | 1104 | if (mem_cgroup_disabled()) |
08e552c6 KH |
1105 | return; |
1106 | mem_cgroup_del_lru_list(page, from); | |
1107 | mem_cgroup_add_lru_list(page, to); | |
66e1707b BS |
1108 | } |
1109 | ||
3e92041d MH |
1110 | /* |
1111 | * Checks whether given mem is same or in the root_mem's | |
1112 | * hierarchy subtree | |
1113 | */ | |
1114 | static bool mem_cgroup_same_or_subtree(const struct mem_cgroup *root_mem, | |
1115 | struct mem_cgroup *mem) | |
1116 | { | |
1117 | if (root_mem != mem) { | |
1118 | return (root_mem->use_hierarchy && | |
1119 | css_is_ancestor(&mem->css, &root_mem->css)); | |
1120 | } | |
1121 | ||
1122 | return true; | |
1123 | } | |
1124 | ||
4c4a2214 DR |
1125 | int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem) |
1126 | { | |
1127 | int ret; | |
0b7f569e | 1128 | struct mem_cgroup *curr = NULL; |
158e0a2d | 1129 | struct task_struct *p; |
4c4a2214 | 1130 | |
158e0a2d KH |
1131 | p = find_lock_task_mm(task); |
1132 | if (!p) | |
1133 | return 0; | |
1134 | curr = try_get_mem_cgroup_from_mm(p->mm); | |
1135 | task_unlock(p); | |
0b7f569e KH |
1136 | if (!curr) |
1137 | return 0; | |
d31f56db DN |
1138 | /* |
1139 | * We should check use_hierarchy of "mem" not "curr". Because checking | |
1140 | * use_hierarchy of "curr" here make this function true if hierarchy is | |
1141 | * enabled in "curr" and "curr" is a child of "mem" in *cgroup* | |
1142 | * hierarchy(even if use_hierarchy is disabled in "mem"). | |
1143 | */ | |
3e92041d | 1144 | ret = mem_cgroup_same_or_subtree(mem, curr); |
0b7f569e | 1145 | css_put(&curr->css); |
4c4a2214 DR |
1146 | return ret; |
1147 | } | |
1148 | ||
c772be93 | 1149 | static int calc_inactive_ratio(struct mem_cgroup *memcg, unsigned long *present_pages) |
14797e23 KM |
1150 | { |
1151 | unsigned long active; | |
1152 | unsigned long inactive; | |
c772be93 KM |
1153 | unsigned long gb; |
1154 | unsigned long inactive_ratio; | |
14797e23 | 1155 | |
bb2a0de9 KH |
1156 | inactive = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_INACTIVE_ANON)); |
1157 | active = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_ACTIVE_ANON)); | |
14797e23 | 1158 | |
c772be93 KM |
1159 | gb = (inactive + active) >> (30 - PAGE_SHIFT); |
1160 | if (gb) | |
1161 | inactive_ratio = int_sqrt(10 * gb); | |
1162 | else | |
1163 | inactive_ratio = 1; | |
1164 | ||
1165 | if (present_pages) { | |
1166 | present_pages[0] = inactive; | |
1167 | present_pages[1] = active; | |
1168 | } | |
1169 | ||
1170 | return inactive_ratio; | |
1171 | } | |
1172 | ||
1173 | int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg) | |
1174 | { | |
1175 | unsigned long active; | |
1176 | unsigned long inactive; | |
1177 | unsigned long present_pages[2]; | |
1178 | unsigned long inactive_ratio; | |
1179 | ||
1180 | inactive_ratio = calc_inactive_ratio(memcg, present_pages); | |
1181 | ||
1182 | inactive = present_pages[0]; | |
1183 | active = present_pages[1]; | |
1184 | ||
1185 | if (inactive * inactive_ratio < active) | |
14797e23 KM |
1186 | return 1; |
1187 | ||
1188 | return 0; | |
1189 | } | |
1190 | ||
56e49d21 RR |
1191 | int mem_cgroup_inactive_file_is_low(struct mem_cgroup *memcg) |
1192 | { | |
1193 | unsigned long active; | |
1194 | unsigned long inactive; | |
1195 | ||
bb2a0de9 KH |
1196 | inactive = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_INACTIVE_FILE)); |
1197 | active = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_ACTIVE_FILE)); | |
56e49d21 RR |
1198 | |
1199 | return (active > inactive); | |
1200 | } | |
1201 | ||
3e2f41f1 KM |
1202 | struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg, |
1203 | struct zone *zone) | |
1204 | { | |
13d7e3a2 | 1205 | int nid = zone_to_nid(zone); |
3e2f41f1 KM |
1206 | int zid = zone_idx(zone); |
1207 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
1208 | ||
1209 | return &mz->reclaim_stat; | |
1210 | } | |
1211 | ||
1212 | struct zone_reclaim_stat * | |
1213 | mem_cgroup_get_reclaim_stat_from_page(struct page *page) | |
1214 | { | |
1215 | struct page_cgroup *pc; | |
1216 | struct mem_cgroup_per_zone *mz; | |
1217 | ||
1218 | if (mem_cgroup_disabled()) | |
1219 | return NULL; | |
1220 | ||
1221 | pc = lookup_page_cgroup(page); | |
bd112db8 DN |
1222 | if (!PageCgroupUsed(pc)) |
1223 | return NULL; | |
713735b4 JW |
1224 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
1225 | smp_rmb(); | |
97a6c37b | 1226 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
3e2f41f1 KM |
1227 | return &mz->reclaim_stat; |
1228 | } | |
1229 | ||
66e1707b BS |
1230 | unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, |
1231 | struct list_head *dst, | |
1232 | unsigned long *scanned, int order, | |
1233 | int mode, struct zone *z, | |
1234 | struct mem_cgroup *mem_cont, | |
4f98a2fe | 1235 | int active, int file) |
66e1707b BS |
1236 | { |
1237 | unsigned long nr_taken = 0; | |
1238 | struct page *page; | |
1239 | unsigned long scan; | |
1240 | LIST_HEAD(pc_list); | |
1241 | struct list_head *src; | |
ff7283fa | 1242 | struct page_cgroup *pc, *tmp; |
13d7e3a2 | 1243 | int nid = zone_to_nid(z); |
1ecaab2b KH |
1244 | int zid = zone_idx(z); |
1245 | struct mem_cgroup_per_zone *mz; | |
b7c46d15 | 1246 | int lru = LRU_FILE * file + active; |
2ffebca6 | 1247 | int ret; |
66e1707b | 1248 | |
cf475ad2 | 1249 | BUG_ON(!mem_cont); |
1ecaab2b | 1250 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); |
b69408e8 | 1251 | src = &mz->lists[lru]; |
66e1707b | 1252 | |
ff7283fa KH |
1253 | scan = 0; |
1254 | list_for_each_entry_safe_reverse(pc, tmp, src, lru) { | |
436c6541 | 1255 | if (scan >= nr_to_scan) |
ff7283fa | 1256 | break; |
08e552c6 | 1257 | |
52d4b9ac KH |
1258 | if (unlikely(!PageCgroupUsed(pc))) |
1259 | continue; | |
5564e88b | 1260 | |
6b3ae58e | 1261 | page = lookup_cgroup_page(pc); |
5564e88b | 1262 | |
436c6541 | 1263 | if (unlikely(!PageLRU(page))) |
ff7283fa | 1264 | continue; |
ff7283fa | 1265 | |
436c6541 | 1266 | scan++; |
2ffebca6 KH |
1267 | ret = __isolate_lru_page(page, mode, file); |
1268 | switch (ret) { | |
1269 | case 0: | |
66e1707b | 1270 | list_move(&page->lru, dst); |
2ffebca6 | 1271 | mem_cgroup_del_lru(page); |
2c888cfb | 1272 | nr_taken += hpage_nr_pages(page); |
2ffebca6 KH |
1273 | break; |
1274 | case -EBUSY: | |
1275 | /* we don't affect global LRU but rotate in our LRU */ | |
1276 | mem_cgroup_rotate_lru_list(page, page_lru(page)); | |
1277 | break; | |
1278 | default: | |
1279 | break; | |
66e1707b BS |
1280 | } |
1281 | } | |
1282 | ||
66e1707b | 1283 | *scanned = scan; |
cc8e970c KM |
1284 | |
1285 | trace_mm_vmscan_memcg_isolate(0, nr_to_scan, scan, nr_taken, | |
1286 | 0, 0, 0, mode); | |
1287 | ||
66e1707b BS |
1288 | return nr_taken; |
1289 | } | |
1290 | ||
6d61ef40 BS |
1291 | #define mem_cgroup_from_res_counter(counter, member) \ |
1292 | container_of(counter, struct mem_cgroup, member) | |
1293 | ||
19942822 | 1294 | /** |
9d11ea9f JW |
1295 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
1296 | * @mem: the memory cgroup | |
19942822 | 1297 | * |
9d11ea9f | 1298 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1299 | * pages. |
19942822 | 1300 | */ |
7ec99d62 | 1301 | static unsigned long mem_cgroup_margin(struct mem_cgroup *mem) |
19942822 | 1302 | { |
9d11ea9f JW |
1303 | unsigned long long margin; |
1304 | ||
1305 | margin = res_counter_margin(&mem->res); | |
1306 | if (do_swap_account) | |
1307 | margin = min(margin, res_counter_margin(&mem->memsw)); | |
7ec99d62 | 1308 | return margin >> PAGE_SHIFT; |
19942822 JW |
1309 | } |
1310 | ||
1f4c025b | 1311 | int mem_cgroup_swappiness(struct mem_cgroup *memcg) |
a7885eb8 KM |
1312 | { |
1313 | struct cgroup *cgrp = memcg->css.cgroup; | |
a7885eb8 KM |
1314 | |
1315 | /* root ? */ | |
1316 | if (cgrp->parent == NULL) | |
1317 | return vm_swappiness; | |
1318 | ||
bf1ff263 | 1319 | return memcg->swappiness; |
a7885eb8 KM |
1320 | } |
1321 | ||
32047e2a KH |
1322 | static void mem_cgroup_start_move(struct mem_cgroup *mem) |
1323 | { | |
1324 | int cpu; | |
1489ebad KH |
1325 | |
1326 | get_online_cpus(); | |
1327 | spin_lock(&mem->pcp_counter_lock); | |
1328 | for_each_online_cpu(cpu) | |
32047e2a | 1329 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) += 1; |
1489ebad KH |
1330 | mem->nocpu_base.count[MEM_CGROUP_ON_MOVE] += 1; |
1331 | spin_unlock(&mem->pcp_counter_lock); | |
1332 | put_online_cpus(); | |
32047e2a KH |
1333 | |
1334 | synchronize_rcu(); | |
1335 | } | |
1336 | ||
1337 | static void mem_cgroup_end_move(struct mem_cgroup *mem) | |
1338 | { | |
1339 | int cpu; | |
1340 | ||
1341 | if (!mem) | |
1342 | return; | |
1489ebad KH |
1343 | get_online_cpus(); |
1344 | spin_lock(&mem->pcp_counter_lock); | |
1345 | for_each_online_cpu(cpu) | |
32047e2a | 1346 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) -= 1; |
1489ebad KH |
1347 | mem->nocpu_base.count[MEM_CGROUP_ON_MOVE] -= 1; |
1348 | spin_unlock(&mem->pcp_counter_lock); | |
1349 | put_online_cpus(); | |
32047e2a KH |
1350 | } |
1351 | /* | |
1352 | * 2 routines for checking "mem" is under move_account() or not. | |
1353 | * | |
1354 | * mem_cgroup_stealed() - checking a cgroup is mc.from or not. This is used | |
1355 | * for avoiding race in accounting. If true, | |
1356 | * pc->mem_cgroup may be overwritten. | |
1357 | * | |
1358 | * mem_cgroup_under_move() - checking a cgroup is mc.from or mc.to or | |
1359 | * under hierarchy of moving cgroups. This is for | |
1360 | * waiting at hith-memory prressure caused by "move". | |
1361 | */ | |
1362 | ||
1363 | static bool mem_cgroup_stealed(struct mem_cgroup *mem) | |
1364 | { | |
1365 | VM_BUG_ON(!rcu_read_lock_held()); | |
1366 | return this_cpu_read(mem->stat->count[MEM_CGROUP_ON_MOVE]) > 0; | |
1367 | } | |
4b534334 KH |
1368 | |
1369 | static bool mem_cgroup_under_move(struct mem_cgroup *mem) | |
1370 | { | |
2bd9bb20 KH |
1371 | struct mem_cgroup *from; |
1372 | struct mem_cgroup *to; | |
4b534334 | 1373 | bool ret = false; |
2bd9bb20 KH |
1374 | /* |
1375 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1376 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1377 | */ | |
1378 | spin_lock(&mc.lock); | |
1379 | from = mc.from; | |
1380 | to = mc.to; | |
1381 | if (!from) | |
1382 | goto unlock; | |
3e92041d MH |
1383 | |
1384 | ret = mem_cgroup_same_or_subtree(mem, from) | |
1385 | || mem_cgroup_same_or_subtree(mem, to); | |
2bd9bb20 KH |
1386 | unlock: |
1387 | spin_unlock(&mc.lock); | |
4b534334 KH |
1388 | return ret; |
1389 | } | |
1390 | ||
1391 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *mem) | |
1392 | { | |
1393 | if (mc.moving_task && current != mc.moving_task) { | |
1394 | if (mem_cgroup_under_move(mem)) { | |
1395 | DEFINE_WAIT(wait); | |
1396 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1397 | /* moving charge context might have finished. */ | |
1398 | if (mc.moving_task) | |
1399 | schedule(); | |
1400 | finish_wait(&mc.waitq, &wait); | |
1401 | return true; | |
1402 | } | |
1403 | } | |
1404 | return false; | |
1405 | } | |
1406 | ||
e222432b | 1407 | /** |
6a6135b6 | 1408 | * mem_cgroup_print_oom_info: Called from OOM with tasklist_lock held in read mode. |
e222432b BS |
1409 | * @memcg: The memory cgroup that went over limit |
1410 | * @p: Task that is going to be killed | |
1411 | * | |
1412 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1413 | * enabled | |
1414 | */ | |
1415 | void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) | |
1416 | { | |
1417 | struct cgroup *task_cgrp; | |
1418 | struct cgroup *mem_cgrp; | |
1419 | /* | |
1420 | * Need a buffer in BSS, can't rely on allocations. The code relies | |
1421 | * on the assumption that OOM is serialized for memory controller. | |
1422 | * If this assumption is broken, revisit this code. | |
1423 | */ | |
1424 | static char memcg_name[PATH_MAX]; | |
1425 | int ret; | |
1426 | ||
d31f56db | 1427 | if (!memcg || !p) |
e222432b BS |
1428 | return; |
1429 | ||
1430 | ||
1431 | rcu_read_lock(); | |
1432 | ||
1433 | mem_cgrp = memcg->css.cgroup; | |
1434 | task_cgrp = task_cgroup(p, mem_cgroup_subsys_id); | |
1435 | ||
1436 | ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX); | |
1437 | if (ret < 0) { | |
1438 | /* | |
1439 | * Unfortunately, we are unable to convert to a useful name | |
1440 | * But we'll still print out the usage information | |
1441 | */ | |
1442 | rcu_read_unlock(); | |
1443 | goto done; | |
1444 | } | |
1445 | rcu_read_unlock(); | |
1446 | ||
1447 | printk(KERN_INFO "Task in %s killed", memcg_name); | |
1448 | ||
1449 | rcu_read_lock(); | |
1450 | ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX); | |
1451 | if (ret < 0) { | |
1452 | rcu_read_unlock(); | |
1453 | goto done; | |
1454 | } | |
1455 | rcu_read_unlock(); | |
1456 | ||
1457 | /* | |
1458 | * Continues from above, so we don't need an KERN_ level | |
1459 | */ | |
1460 | printk(KERN_CONT " as a result of limit of %s\n", memcg_name); | |
1461 | done: | |
1462 | ||
1463 | printk(KERN_INFO "memory: usage %llukB, limit %llukB, failcnt %llu\n", | |
1464 | res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, | |
1465 | res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, | |
1466 | res_counter_read_u64(&memcg->res, RES_FAILCNT)); | |
1467 | printk(KERN_INFO "memory+swap: usage %llukB, limit %llukB, " | |
1468 | "failcnt %llu\n", | |
1469 | res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, | |
1470 | res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, | |
1471 | res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); | |
1472 | } | |
1473 | ||
81d39c20 KH |
1474 | /* |
1475 | * This function returns the number of memcg under hierarchy tree. Returns | |
1476 | * 1(self count) if no children. | |
1477 | */ | |
1478 | static int mem_cgroup_count_children(struct mem_cgroup *mem) | |
1479 | { | |
1480 | int num = 0; | |
7d74b06f KH |
1481 | struct mem_cgroup *iter; |
1482 | ||
1483 | for_each_mem_cgroup_tree(iter, mem) | |
1484 | num++; | |
81d39c20 KH |
1485 | return num; |
1486 | } | |
1487 | ||
a63d83f4 DR |
1488 | /* |
1489 | * Return the memory (and swap, if configured) limit for a memcg. | |
1490 | */ | |
1491 | u64 mem_cgroup_get_limit(struct mem_cgroup *memcg) | |
1492 | { | |
1493 | u64 limit; | |
1494 | u64 memsw; | |
1495 | ||
f3e8eb70 JW |
1496 | limit = res_counter_read_u64(&memcg->res, RES_LIMIT); |
1497 | limit += total_swap_pages << PAGE_SHIFT; | |
1498 | ||
a63d83f4 DR |
1499 | memsw = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
1500 | /* | |
1501 | * If memsw is finite and limits the amount of swap space available | |
1502 | * to this memcg, return that limit. | |
1503 | */ | |
1504 | return min(limit, memsw); | |
1505 | } | |
1506 | ||
6d61ef40 | 1507 | /* |
04046e1a KH |
1508 | * Visit the first child (need not be the first child as per the ordering |
1509 | * of the cgroup list, since we track last_scanned_child) of @mem and use | |
1510 | * that to reclaim free pages from. | |
1511 | */ | |
1512 | static struct mem_cgroup * | |
1513 | mem_cgroup_select_victim(struct mem_cgroup *root_mem) | |
1514 | { | |
1515 | struct mem_cgroup *ret = NULL; | |
1516 | struct cgroup_subsys_state *css; | |
1517 | int nextid, found; | |
1518 | ||
1519 | if (!root_mem->use_hierarchy) { | |
1520 | css_get(&root_mem->css); | |
1521 | ret = root_mem; | |
1522 | } | |
1523 | ||
1524 | while (!ret) { | |
1525 | rcu_read_lock(); | |
1526 | nextid = root_mem->last_scanned_child + 1; | |
1527 | css = css_get_next(&mem_cgroup_subsys, nextid, &root_mem->css, | |
1528 | &found); | |
1529 | if (css && css_tryget(css)) | |
1530 | ret = container_of(css, struct mem_cgroup, css); | |
1531 | ||
1532 | rcu_read_unlock(); | |
1533 | /* Updates scanning parameter */ | |
04046e1a KH |
1534 | if (!css) { |
1535 | /* this means start scan from ID:1 */ | |
1536 | root_mem->last_scanned_child = 0; | |
1537 | } else | |
1538 | root_mem->last_scanned_child = found; | |
04046e1a KH |
1539 | } |
1540 | ||
1541 | return ret; | |
1542 | } | |
1543 | ||
4d0c066d KH |
1544 | /** |
1545 | * test_mem_cgroup_node_reclaimable | |
1546 | * @mem: the target memcg | |
1547 | * @nid: the node ID to be checked. | |
1548 | * @noswap : specify true here if the user wants flle only information. | |
1549 | * | |
1550 | * This function returns whether the specified memcg contains any | |
1551 | * reclaimable pages on a node. Returns true if there are any reclaimable | |
1552 | * pages in the node. | |
1553 | */ | |
1554 | static bool test_mem_cgroup_node_reclaimable(struct mem_cgroup *mem, | |
1555 | int nid, bool noswap) | |
1556 | { | |
bb2a0de9 | 1557 | if (mem_cgroup_node_nr_lru_pages(mem, nid, LRU_ALL_FILE)) |
4d0c066d KH |
1558 | return true; |
1559 | if (noswap || !total_swap_pages) | |
1560 | return false; | |
bb2a0de9 | 1561 | if (mem_cgroup_node_nr_lru_pages(mem, nid, LRU_ALL_ANON)) |
4d0c066d KH |
1562 | return true; |
1563 | return false; | |
1564 | ||
1565 | } | |
889976db YH |
1566 | #if MAX_NUMNODES > 1 |
1567 | ||
1568 | /* | |
1569 | * Always updating the nodemask is not very good - even if we have an empty | |
1570 | * list or the wrong list here, we can start from some node and traverse all | |
1571 | * nodes based on the zonelist. So update the list loosely once per 10 secs. | |
1572 | * | |
1573 | */ | |
1574 | static void mem_cgroup_may_update_nodemask(struct mem_cgroup *mem) | |
1575 | { | |
1576 | int nid; | |
453a9bf3 KH |
1577 | /* |
1578 | * numainfo_events > 0 means there was at least NUMAINFO_EVENTS_TARGET | |
1579 | * pagein/pageout changes since the last update. | |
1580 | */ | |
1581 | if (!atomic_read(&mem->numainfo_events)) | |
1582 | return; | |
1583 | if (atomic_inc_return(&mem->numainfo_updating) > 1) | |
889976db YH |
1584 | return; |
1585 | ||
889976db YH |
1586 | /* make a nodemask where this memcg uses memory from */ |
1587 | mem->scan_nodes = node_states[N_HIGH_MEMORY]; | |
1588 | ||
1589 | for_each_node_mask(nid, node_states[N_HIGH_MEMORY]) { | |
1590 | ||
4d0c066d KH |
1591 | if (!test_mem_cgroup_node_reclaimable(mem, nid, false)) |
1592 | node_clear(nid, mem->scan_nodes); | |
889976db | 1593 | } |
453a9bf3 KH |
1594 | |
1595 | atomic_set(&mem->numainfo_events, 0); | |
1596 | atomic_set(&mem->numainfo_updating, 0); | |
889976db YH |
1597 | } |
1598 | ||
1599 | /* | |
1600 | * Selecting a node where we start reclaim from. Because what we need is just | |
1601 | * reducing usage counter, start from anywhere is O,K. Considering | |
1602 | * memory reclaim from current node, there are pros. and cons. | |
1603 | * | |
1604 | * Freeing memory from current node means freeing memory from a node which | |
1605 | * we'll use or we've used. So, it may make LRU bad. And if several threads | |
1606 | * hit limits, it will see a contention on a node. But freeing from remote | |
1607 | * node means more costs for memory reclaim because of memory latency. | |
1608 | * | |
1609 | * Now, we use round-robin. Better algorithm is welcomed. | |
1610 | */ | |
1611 | int mem_cgroup_select_victim_node(struct mem_cgroup *mem) | |
1612 | { | |
1613 | int node; | |
1614 | ||
1615 | mem_cgroup_may_update_nodemask(mem); | |
1616 | node = mem->last_scanned_node; | |
1617 | ||
1618 | node = next_node(node, mem->scan_nodes); | |
1619 | if (node == MAX_NUMNODES) | |
1620 | node = first_node(mem->scan_nodes); | |
1621 | /* | |
1622 | * We call this when we hit limit, not when pages are added to LRU. | |
1623 | * No LRU may hold pages because all pages are UNEVICTABLE or | |
1624 | * memcg is too small and all pages are not on LRU. In that case, | |
1625 | * we use curret node. | |
1626 | */ | |
1627 | if (unlikely(node == MAX_NUMNODES)) | |
1628 | node = numa_node_id(); | |
1629 | ||
1630 | mem->last_scanned_node = node; | |
1631 | return node; | |
1632 | } | |
1633 | ||
4d0c066d KH |
1634 | /* |
1635 | * Check all nodes whether it contains reclaimable pages or not. | |
1636 | * For quick scan, we make use of scan_nodes. This will allow us to skip | |
1637 | * unused nodes. But scan_nodes is lazily updated and may not cotain | |
1638 | * enough new information. We need to do double check. | |
1639 | */ | |
1640 | bool mem_cgroup_reclaimable(struct mem_cgroup *mem, bool noswap) | |
1641 | { | |
1642 | int nid; | |
1643 | ||
1644 | /* | |
1645 | * quick check...making use of scan_node. | |
1646 | * We can skip unused nodes. | |
1647 | */ | |
1648 | if (!nodes_empty(mem->scan_nodes)) { | |
1649 | for (nid = first_node(mem->scan_nodes); | |
1650 | nid < MAX_NUMNODES; | |
1651 | nid = next_node(nid, mem->scan_nodes)) { | |
1652 | ||
1653 | if (test_mem_cgroup_node_reclaimable(mem, nid, noswap)) | |
1654 | return true; | |
1655 | } | |
1656 | } | |
1657 | /* | |
1658 | * Check rest of nodes. | |
1659 | */ | |
1660 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
1661 | if (node_isset(nid, mem->scan_nodes)) | |
1662 | continue; | |
1663 | if (test_mem_cgroup_node_reclaimable(mem, nid, noswap)) | |
1664 | return true; | |
1665 | } | |
1666 | return false; | |
1667 | } | |
1668 | ||
889976db YH |
1669 | #else |
1670 | int mem_cgroup_select_victim_node(struct mem_cgroup *mem) | |
1671 | { | |
1672 | return 0; | |
1673 | } | |
4d0c066d KH |
1674 | |
1675 | bool mem_cgroup_reclaimable(struct mem_cgroup *mem, bool noswap) | |
1676 | { | |
1677 | return test_mem_cgroup_node_reclaimable(mem, 0, noswap); | |
1678 | } | |
889976db YH |
1679 | #endif |
1680 | ||
82f9d486 KH |
1681 | static void __mem_cgroup_record_scanstat(unsigned long *stats, |
1682 | struct memcg_scanrecord *rec) | |
1683 | { | |
1684 | ||
1685 | stats[SCAN] += rec->nr_scanned[0] + rec->nr_scanned[1]; | |
1686 | stats[SCAN_ANON] += rec->nr_scanned[0]; | |
1687 | stats[SCAN_FILE] += rec->nr_scanned[1]; | |
1688 | ||
1689 | stats[ROTATE] += rec->nr_rotated[0] + rec->nr_rotated[1]; | |
1690 | stats[ROTATE_ANON] += rec->nr_rotated[0]; | |
1691 | stats[ROTATE_FILE] += rec->nr_rotated[1]; | |
1692 | ||
1693 | stats[FREED] += rec->nr_freed[0] + rec->nr_freed[1]; | |
1694 | stats[FREED_ANON] += rec->nr_freed[0]; | |
1695 | stats[FREED_FILE] += rec->nr_freed[1]; | |
1696 | ||
1697 | stats[ELAPSED] += rec->elapsed; | |
1698 | } | |
1699 | ||
1700 | static void mem_cgroup_record_scanstat(struct memcg_scanrecord *rec) | |
1701 | { | |
1702 | struct mem_cgroup *mem; | |
1703 | int context = rec->context; | |
1704 | ||
1705 | if (context >= NR_SCAN_CONTEXT) | |
1706 | return; | |
1707 | ||
1708 | mem = rec->mem; | |
1709 | spin_lock(&mem->scanstat.lock); | |
1710 | __mem_cgroup_record_scanstat(mem->scanstat.stats[context], rec); | |
1711 | spin_unlock(&mem->scanstat.lock); | |
1712 | ||
1713 | mem = rec->root; | |
1714 | spin_lock(&mem->scanstat.lock); | |
1715 | __mem_cgroup_record_scanstat(mem->scanstat.rootstats[context], rec); | |
1716 | spin_unlock(&mem->scanstat.lock); | |
1717 | } | |
1718 | ||
04046e1a KH |
1719 | /* |
1720 | * Scan the hierarchy if needed to reclaim memory. We remember the last child | |
1721 | * we reclaimed from, so that we don't end up penalizing one child extensively | |
1722 | * based on its position in the children list. | |
6d61ef40 BS |
1723 | * |
1724 | * root_mem is the original ancestor that we've been reclaim from. | |
04046e1a KH |
1725 | * |
1726 | * We give up and return to the caller when we visit root_mem twice. | |
1727 | * (other groups can be removed while we're walking....) | |
81d39c20 KH |
1728 | * |
1729 | * If shrink==true, for avoiding to free too much, this returns immedieately. | |
6d61ef40 BS |
1730 | */ |
1731 | static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, | |
4e416953 | 1732 | struct zone *zone, |
75822b44 | 1733 | gfp_t gfp_mask, |
0ae5e89c YH |
1734 | unsigned long reclaim_options, |
1735 | unsigned long *total_scanned) | |
6d61ef40 | 1736 | { |
04046e1a KH |
1737 | struct mem_cgroup *victim; |
1738 | int ret, total = 0; | |
1739 | int loop = 0; | |
75822b44 BS |
1740 | bool noswap = reclaim_options & MEM_CGROUP_RECLAIM_NOSWAP; |
1741 | bool shrink = reclaim_options & MEM_CGROUP_RECLAIM_SHRINK; | |
4e416953 | 1742 | bool check_soft = reclaim_options & MEM_CGROUP_RECLAIM_SOFT; |
82f9d486 | 1743 | struct memcg_scanrecord rec; |
9d11ea9f | 1744 | unsigned long excess; |
82f9d486 | 1745 | unsigned long scanned; |
9d11ea9f JW |
1746 | |
1747 | excess = res_counter_soft_limit_excess(&root_mem->res) >> PAGE_SHIFT; | |
04046e1a | 1748 | |
22a668d7 | 1749 | /* If memsw_is_minimum==1, swap-out is of-no-use. */ |
108b6a78 | 1750 | if (!check_soft && !shrink && root_mem->memsw_is_minimum) |
22a668d7 KH |
1751 | noswap = true; |
1752 | ||
82f9d486 KH |
1753 | if (shrink) |
1754 | rec.context = SCAN_BY_SHRINK; | |
1755 | else if (check_soft) | |
1756 | rec.context = SCAN_BY_SYSTEM; | |
1757 | else | |
1758 | rec.context = SCAN_BY_LIMIT; | |
1759 | ||
1760 | rec.root = root_mem; | |
1761 | ||
4e416953 | 1762 | while (1) { |
04046e1a | 1763 | victim = mem_cgroup_select_victim(root_mem); |
4e416953 | 1764 | if (victim == root_mem) { |
04046e1a | 1765 | loop++; |
fbc29a25 KH |
1766 | /* |
1767 | * We are not draining per cpu cached charges during | |
1768 | * soft limit reclaim because global reclaim doesn't | |
1769 | * care about charges. It tries to free some memory and | |
1770 | * charges will not give any. | |
1771 | */ | |
1772 | if (!check_soft && loop >= 1) | |
26fe6168 | 1773 | drain_all_stock_async(root_mem); |
4e416953 BS |
1774 | if (loop >= 2) { |
1775 | /* | |
1776 | * If we have not been able to reclaim | |
1777 | * anything, it might because there are | |
1778 | * no reclaimable pages under this hierarchy | |
1779 | */ | |
1780 | if (!check_soft || !total) { | |
1781 | css_put(&victim->css); | |
1782 | break; | |
1783 | } | |
1784 | /* | |
25985edc | 1785 | * We want to do more targeted reclaim. |
4e416953 BS |
1786 | * excess >> 2 is not to excessive so as to |
1787 | * reclaim too much, nor too less that we keep | |
1788 | * coming back to reclaim from this cgroup | |
1789 | */ | |
1790 | if (total >= (excess >> 2) || | |
1791 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) { | |
1792 | css_put(&victim->css); | |
1793 | break; | |
1794 | } | |
1795 | } | |
1796 | } | |
4d0c066d | 1797 | if (!mem_cgroup_reclaimable(victim, noswap)) { |
04046e1a KH |
1798 | /* this cgroup's local usage == 0 */ |
1799 | css_put(&victim->css); | |
6d61ef40 BS |
1800 | continue; |
1801 | } | |
82f9d486 KH |
1802 | rec.mem = victim; |
1803 | rec.nr_scanned[0] = 0; | |
1804 | rec.nr_scanned[1] = 0; | |
1805 | rec.nr_rotated[0] = 0; | |
1806 | rec.nr_rotated[1] = 0; | |
1807 | rec.nr_freed[0] = 0; | |
1808 | rec.nr_freed[1] = 0; | |
1809 | rec.elapsed = 0; | |
04046e1a | 1810 | /* we use swappiness of local cgroup */ |
0ae5e89c | 1811 | if (check_soft) { |
4e416953 | 1812 | ret = mem_cgroup_shrink_node_zone(victim, gfp_mask, |
82f9d486 KH |
1813 | noswap, zone, &rec, &scanned); |
1814 | *total_scanned += scanned; | |
0ae5e89c | 1815 | } else |
4e416953 | 1816 | ret = try_to_free_mem_cgroup_pages(victim, gfp_mask, |
82f9d486 KH |
1817 | noswap, &rec); |
1818 | mem_cgroup_record_scanstat(&rec); | |
04046e1a | 1819 | css_put(&victim->css); |
81d39c20 KH |
1820 | /* |
1821 | * At shrinking usage, we can't check we should stop here or | |
1822 | * reclaim more. It's depends on callers. last_scanned_child | |
1823 | * will work enough for keeping fairness under tree. | |
1824 | */ | |
1825 | if (shrink) | |
1826 | return ret; | |
04046e1a | 1827 | total += ret; |
4e416953 | 1828 | if (check_soft) { |
9d11ea9f | 1829 | if (!res_counter_soft_limit_excess(&root_mem->res)) |
4e416953 | 1830 | return total; |
9d11ea9f | 1831 | } else if (mem_cgroup_margin(root_mem)) |
4fd14ebf | 1832 | return total; |
6d61ef40 | 1833 | } |
04046e1a | 1834 | return total; |
6d61ef40 BS |
1835 | } |
1836 | ||
867578cb KH |
1837 | /* |
1838 | * Check OOM-Killer is already running under our hierarchy. | |
1839 | * If someone is running, return false. | |
1af8efe9 | 1840 | * Has to be called with memcg_oom_lock |
867578cb KH |
1841 | */ |
1842 | static bool mem_cgroup_oom_lock(struct mem_cgroup *mem) | |
1843 | { | |
79dfdacc MH |
1844 | int lock_count = -1; |
1845 | struct mem_cgroup *iter, *failed = NULL; | |
1846 | bool cond = true; | |
a636b327 | 1847 | |
79dfdacc MH |
1848 | for_each_mem_cgroup_tree_cond(iter, mem, cond) { |
1849 | bool locked = iter->oom_lock; | |
1850 | ||
1851 | iter->oom_lock = true; | |
1852 | if (lock_count == -1) | |
1853 | lock_count = iter->oom_lock; | |
1854 | else if (lock_count != locked) { | |
1855 | /* | |
1856 | * this subtree of our hierarchy is already locked | |
1857 | * so we cannot give a lock. | |
1858 | */ | |
1859 | lock_count = 0; | |
1860 | failed = iter; | |
1861 | cond = false; | |
1862 | } | |
7d74b06f | 1863 | } |
867578cb | 1864 | |
79dfdacc MH |
1865 | if (!failed) |
1866 | goto done; | |
1867 | ||
1868 | /* | |
1869 | * OK, we failed to lock the whole subtree so we have to clean up | |
1870 | * what we set up to the failing subtree | |
1871 | */ | |
1872 | cond = true; | |
1873 | for_each_mem_cgroup_tree_cond(iter, mem, cond) { | |
1874 | if (iter == failed) { | |
1875 | cond = false; | |
1876 | continue; | |
1877 | } | |
1878 | iter->oom_lock = false; | |
1879 | } | |
1880 | done: | |
1881 | return lock_count; | |
a636b327 | 1882 | } |
0b7f569e | 1883 | |
79dfdacc | 1884 | /* |
1af8efe9 | 1885 | * Has to be called with memcg_oom_lock |
79dfdacc | 1886 | */ |
7d74b06f | 1887 | static int mem_cgroup_oom_unlock(struct mem_cgroup *mem) |
0b7f569e | 1888 | { |
7d74b06f KH |
1889 | struct mem_cgroup *iter; |
1890 | ||
79dfdacc MH |
1891 | for_each_mem_cgroup_tree(iter, mem) |
1892 | iter->oom_lock = false; | |
1893 | return 0; | |
1894 | } | |
1895 | ||
1896 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *mem) | |
1897 | { | |
1898 | struct mem_cgroup *iter; | |
1899 | ||
1900 | for_each_mem_cgroup_tree(iter, mem) | |
1901 | atomic_inc(&iter->under_oom); | |
1902 | } | |
1903 | ||
1904 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *mem) | |
1905 | { | |
1906 | struct mem_cgroup *iter; | |
1907 | ||
867578cb KH |
1908 | /* |
1909 | * When a new child is created while the hierarchy is under oom, | |
1910 | * mem_cgroup_oom_lock() may not be called. We have to use | |
1911 | * atomic_add_unless() here. | |
1912 | */ | |
7d74b06f | 1913 | for_each_mem_cgroup_tree(iter, mem) |
79dfdacc | 1914 | atomic_add_unless(&iter->under_oom, -1, 0); |
0b7f569e KH |
1915 | } |
1916 | ||
1af8efe9 | 1917 | static DEFINE_SPINLOCK(memcg_oom_lock); |
867578cb KH |
1918 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1919 | ||
dc98df5a KH |
1920 | struct oom_wait_info { |
1921 | struct mem_cgroup *mem; | |
1922 | wait_queue_t wait; | |
1923 | }; | |
1924 | ||
1925 | static int memcg_oom_wake_function(wait_queue_t *wait, | |
1926 | unsigned mode, int sync, void *arg) | |
1927 | { | |
3e92041d MH |
1928 | struct mem_cgroup *wake_mem = (struct mem_cgroup *)arg, |
1929 | *oom_wait_mem; | |
dc98df5a KH |
1930 | struct oom_wait_info *oom_wait_info; |
1931 | ||
1932 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
3e92041d | 1933 | oom_wait_mem = oom_wait_info->mem; |
dc98df5a | 1934 | |
dc98df5a KH |
1935 | /* |
1936 | * Both of oom_wait_info->mem and wake_mem are stable under us. | |
1937 | * Then we can use css_is_ancestor without taking care of RCU. | |
1938 | */ | |
3e92041d MH |
1939 | if (!mem_cgroup_same_or_subtree(oom_wait_mem, wake_mem) |
1940 | && !mem_cgroup_same_or_subtree(wake_mem, oom_wait_mem)) | |
dc98df5a | 1941 | return 0; |
dc98df5a KH |
1942 | return autoremove_wake_function(wait, mode, sync, arg); |
1943 | } | |
1944 | ||
1945 | static void memcg_wakeup_oom(struct mem_cgroup *mem) | |
1946 | { | |
1947 | /* for filtering, pass "mem" as argument. */ | |
1948 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, mem); | |
1949 | } | |
1950 | ||
3c11ecf4 KH |
1951 | static void memcg_oom_recover(struct mem_cgroup *mem) |
1952 | { | |
79dfdacc | 1953 | if (mem && atomic_read(&mem->under_oom)) |
3c11ecf4 KH |
1954 | memcg_wakeup_oom(mem); |
1955 | } | |
1956 | ||
867578cb KH |
1957 | /* |
1958 | * try to call OOM killer. returns false if we should exit memory-reclaim loop. | |
1959 | */ | |
1960 | bool mem_cgroup_handle_oom(struct mem_cgroup *mem, gfp_t mask) | |
0b7f569e | 1961 | { |
dc98df5a | 1962 | struct oom_wait_info owait; |
3c11ecf4 | 1963 | bool locked, need_to_kill; |
867578cb | 1964 | |
dc98df5a KH |
1965 | owait.mem = mem; |
1966 | owait.wait.flags = 0; | |
1967 | owait.wait.func = memcg_oom_wake_function; | |
1968 | owait.wait.private = current; | |
1969 | INIT_LIST_HEAD(&owait.wait.task_list); | |
3c11ecf4 | 1970 | need_to_kill = true; |
79dfdacc MH |
1971 | mem_cgroup_mark_under_oom(mem); |
1972 | ||
867578cb | 1973 | /* At first, try to OOM lock hierarchy under mem.*/ |
1af8efe9 | 1974 | spin_lock(&memcg_oom_lock); |
867578cb KH |
1975 | locked = mem_cgroup_oom_lock(mem); |
1976 | /* | |
1977 | * Even if signal_pending(), we can't quit charge() loop without | |
1978 | * accounting. So, UNINTERRUPTIBLE is appropriate. But SIGKILL | |
1979 | * under OOM is always welcomed, use TASK_KILLABLE here. | |
1980 | */ | |
3c11ecf4 KH |
1981 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
1982 | if (!locked || mem->oom_kill_disable) | |
1983 | need_to_kill = false; | |
1984 | if (locked) | |
9490ff27 | 1985 | mem_cgroup_oom_notify(mem); |
1af8efe9 | 1986 | spin_unlock(&memcg_oom_lock); |
867578cb | 1987 | |
3c11ecf4 KH |
1988 | if (need_to_kill) { |
1989 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
867578cb | 1990 | mem_cgroup_out_of_memory(mem, mask); |
3c11ecf4 | 1991 | } else { |
867578cb | 1992 | schedule(); |
dc98df5a | 1993 | finish_wait(&memcg_oom_waitq, &owait.wait); |
867578cb | 1994 | } |
1af8efe9 | 1995 | spin_lock(&memcg_oom_lock); |
79dfdacc MH |
1996 | if (locked) |
1997 | mem_cgroup_oom_unlock(mem); | |
dc98df5a | 1998 | memcg_wakeup_oom(mem); |
1af8efe9 | 1999 | spin_unlock(&memcg_oom_lock); |
867578cb | 2000 | |
79dfdacc MH |
2001 | mem_cgroup_unmark_under_oom(mem); |
2002 | ||
867578cb KH |
2003 | if (test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current)) |
2004 | return false; | |
2005 | /* Give chance to dying process */ | |
2006 | schedule_timeout(1); | |
2007 | return true; | |
0b7f569e KH |
2008 | } |
2009 | ||
d69b042f BS |
2010 | /* |
2011 | * Currently used to update mapped file statistics, but the routine can be | |
2012 | * generalized to update other statistics as well. | |
32047e2a KH |
2013 | * |
2014 | * Notes: Race condition | |
2015 | * | |
2016 | * We usually use page_cgroup_lock() for accessing page_cgroup member but | |
2017 | * it tends to be costly. But considering some conditions, we doesn't need | |
2018 | * to do so _always_. | |
2019 | * | |
2020 | * Considering "charge", lock_page_cgroup() is not required because all | |
2021 | * file-stat operations happen after a page is attached to radix-tree. There | |
2022 | * are no race with "charge". | |
2023 | * | |
2024 | * Considering "uncharge", we know that memcg doesn't clear pc->mem_cgroup | |
2025 | * at "uncharge" intentionally. So, we always see valid pc->mem_cgroup even | |
2026 | * if there are race with "uncharge". Statistics itself is properly handled | |
2027 | * by flags. | |
2028 | * | |
2029 | * Considering "move", this is an only case we see a race. To make the race | |
2030 | * small, we check MEM_CGROUP_ON_MOVE percpu value and detect there are | |
2031 | * possibility of race condition. If there is, we take a lock. | |
d69b042f | 2032 | */ |
26174efd | 2033 | |
2a7106f2 GT |
2034 | void mem_cgroup_update_page_stat(struct page *page, |
2035 | enum mem_cgroup_page_stat_item idx, int val) | |
d69b042f BS |
2036 | { |
2037 | struct mem_cgroup *mem; | |
32047e2a KH |
2038 | struct page_cgroup *pc = lookup_page_cgroup(page); |
2039 | bool need_unlock = false; | |
dbd4ea78 | 2040 | unsigned long uninitialized_var(flags); |
d69b042f | 2041 | |
d69b042f BS |
2042 | if (unlikely(!pc)) |
2043 | return; | |
2044 | ||
32047e2a | 2045 | rcu_read_lock(); |
d69b042f | 2046 | mem = pc->mem_cgroup; |
32047e2a KH |
2047 | if (unlikely(!mem || !PageCgroupUsed(pc))) |
2048 | goto out; | |
2049 | /* pc->mem_cgroup is unstable ? */ | |
ca3e0214 | 2050 | if (unlikely(mem_cgroup_stealed(mem)) || PageTransHuge(page)) { |
32047e2a | 2051 | /* take a lock against to access pc->mem_cgroup */ |
dbd4ea78 | 2052 | move_lock_page_cgroup(pc, &flags); |
32047e2a KH |
2053 | need_unlock = true; |
2054 | mem = pc->mem_cgroup; | |
2055 | if (!mem || !PageCgroupUsed(pc)) | |
2056 | goto out; | |
2057 | } | |
26174efd | 2058 | |
26174efd | 2059 | switch (idx) { |
2a7106f2 | 2060 | case MEMCG_NR_FILE_MAPPED: |
26174efd KH |
2061 | if (val > 0) |
2062 | SetPageCgroupFileMapped(pc); | |
2063 | else if (!page_mapped(page)) | |
0c270f8f | 2064 | ClearPageCgroupFileMapped(pc); |
2a7106f2 | 2065 | idx = MEM_CGROUP_STAT_FILE_MAPPED; |
26174efd KH |
2066 | break; |
2067 | default: | |
2068 | BUG(); | |
8725d541 | 2069 | } |
d69b042f | 2070 | |
2a7106f2 GT |
2071 | this_cpu_add(mem->stat->count[idx], val); |
2072 | ||
32047e2a KH |
2073 | out: |
2074 | if (unlikely(need_unlock)) | |
dbd4ea78 | 2075 | move_unlock_page_cgroup(pc, &flags); |
32047e2a KH |
2076 | rcu_read_unlock(); |
2077 | return; | |
d69b042f | 2078 | } |
2a7106f2 | 2079 | EXPORT_SYMBOL(mem_cgroup_update_page_stat); |
26174efd | 2080 | |
cdec2e42 KH |
2081 | /* |
2082 | * size of first charge trial. "32" comes from vmscan.c's magic value. | |
2083 | * TODO: maybe necessary to use big numbers in big irons. | |
2084 | */ | |
7ec99d62 | 2085 | #define CHARGE_BATCH 32U |
cdec2e42 KH |
2086 | struct memcg_stock_pcp { |
2087 | struct mem_cgroup *cached; /* this never be root cgroup */ | |
11c9ea4e | 2088 | unsigned int nr_pages; |
cdec2e42 | 2089 | struct work_struct work; |
26fe6168 KH |
2090 | unsigned long flags; |
2091 | #define FLUSHING_CACHED_CHARGE (0) | |
cdec2e42 KH |
2092 | }; |
2093 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); | |
cdec2e42 KH |
2094 | |
2095 | /* | |
11c9ea4e | 2096 | * Try to consume stocked charge on this cpu. If success, one page is consumed |
cdec2e42 KH |
2097 | * from local stock and true is returned. If the stock is 0 or charges from a |
2098 | * cgroup which is not current target, returns false. This stock will be | |
2099 | * refilled. | |
2100 | */ | |
2101 | static bool consume_stock(struct mem_cgroup *mem) | |
2102 | { | |
2103 | struct memcg_stock_pcp *stock; | |
2104 | bool ret = true; | |
2105 | ||
2106 | stock = &get_cpu_var(memcg_stock); | |
11c9ea4e JW |
2107 | if (mem == stock->cached && stock->nr_pages) |
2108 | stock->nr_pages--; | |
cdec2e42 KH |
2109 | else /* need to call res_counter_charge */ |
2110 | ret = false; | |
2111 | put_cpu_var(memcg_stock); | |
2112 | return ret; | |
2113 | } | |
2114 | ||
2115 | /* | |
2116 | * Returns stocks cached in percpu to res_counter and reset cached information. | |
2117 | */ | |
2118 | static void drain_stock(struct memcg_stock_pcp *stock) | |
2119 | { | |
2120 | struct mem_cgroup *old = stock->cached; | |
2121 | ||
11c9ea4e JW |
2122 | if (stock->nr_pages) { |
2123 | unsigned long bytes = stock->nr_pages * PAGE_SIZE; | |
2124 | ||
2125 | res_counter_uncharge(&old->res, bytes); | |
cdec2e42 | 2126 | if (do_swap_account) |
11c9ea4e JW |
2127 | res_counter_uncharge(&old->memsw, bytes); |
2128 | stock->nr_pages = 0; | |
cdec2e42 KH |
2129 | } |
2130 | stock->cached = NULL; | |
cdec2e42 KH |
2131 | } |
2132 | ||
2133 | /* | |
2134 | * This must be called under preempt disabled or must be called by | |
2135 | * a thread which is pinned to local cpu. | |
2136 | */ | |
2137 | static void drain_local_stock(struct work_struct *dummy) | |
2138 | { | |
2139 | struct memcg_stock_pcp *stock = &__get_cpu_var(memcg_stock); | |
2140 | drain_stock(stock); | |
26fe6168 | 2141 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
cdec2e42 KH |
2142 | } |
2143 | ||
2144 | /* | |
2145 | * Cache charges(val) which is from res_counter, to local per_cpu area. | |
320cc51d | 2146 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 2147 | */ |
11c9ea4e | 2148 | static void refill_stock(struct mem_cgroup *mem, unsigned int nr_pages) |
cdec2e42 KH |
2149 | { |
2150 | struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock); | |
2151 | ||
2152 | if (stock->cached != mem) { /* reset if necessary */ | |
2153 | drain_stock(stock); | |
2154 | stock->cached = mem; | |
2155 | } | |
11c9ea4e | 2156 | stock->nr_pages += nr_pages; |
cdec2e42 KH |
2157 | put_cpu_var(memcg_stock); |
2158 | } | |
2159 | ||
2160 | /* | |
d38144b7 MH |
2161 | * Drains all per-CPU charge caches for given root_mem resp. subtree |
2162 | * of the hierarchy under it. sync flag says whether we should block | |
2163 | * until the work is done. | |
cdec2e42 | 2164 | */ |
d38144b7 | 2165 | static void drain_all_stock(struct mem_cgroup *root_mem, bool sync) |
cdec2e42 | 2166 | { |
26fe6168 | 2167 | int cpu, curcpu; |
d38144b7 | 2168 | |
cdec2e42 | 2169 | /* Notify other cpus that system-wide "drain" is running */ |
cdec2e42 | 2170 | get_online_cpus(); |
26fe6168 KH |
2171 | /* |
2172 | * Get a hint for avoiding draining charges on the current cpu, | |
2173 | * which must be exhausted by our charging. It is not required that | |
2174 | * this be a precise check, so we use raw_smp_processor_id() instead of | |
2175 | * getcpu()/putcpu(). | |
2176 | */ | |
2177 | curcpu = raw_smp_processor_id(); | |
cdec2e42 KH |
2178 | for_each_online_cpu(cpu) { |
2179 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
26fe6168 KH |
2180 | struct mem_cgroup *mem; |
2181 | ||
26fe6168 | 2182 | mem = stock->cached; |
d1a05b69 | 2183 | if (!mem || !stock->nr_pages) |
26fe6168 | 2184 | continue; |
3e92041d MH |
2185 | if (!mem_cgroup_same_or_subtree(root_mem, mem)) |
2186 | continue; | |
d1a05b69 MH |
2187 | if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { |
2188 | if (cpu == curcpu) | |
2189 | drain_local_stock(&stock->work); | |
2190 | else | |
2191 | schedule_work_on(cpu, &stock->work); | |
2192 | } | |
cdec2e42 | 2193 | } |
d38144b7 MH |
2194 | |
2195 | if (!sync) | |
2196 | goto out; | |
2197 | ||
2198 | for_each_online_cpu(cpu) { | |
2199 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
8521fc50 MH |
2200 | if (mem_cgroup_same_or_subtree(root_mem, stock->cached) && |
2201 | test_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) | |
d38144b7 MH |
2202 | flush_work(&stock->work); |
2203 | } | |
2204 | out: | |
cdec2e42 | 2205 | put_online_cpus(); |
d38144b7 MH |
2206 | } |
2207 | ||
2208 | /* | |
2209 | * Tries to drain stocked charges in other cpus. This function is asynchronous | |
2210 | * and just put a work per cpu for draining localy on each cpu. Caller can | |
2211 | * expects some charges will be back to res_counter later but cannot wait for | |
2212 | * it. | |
2213 | */ | |
2214 | static void drain_all_stock_async(struct mem_cgroup *root_mem) | |
2215 | { | |
d38144b7 | 2216 | drain_all_stock(root_mem, false); |
cdec2e42 KH |
2217 | } |
2218 | ||
2219 | /* This is a synchronous drain interface. */ | |
d38144b7 | 2220 | static void drain_all_stock_sync(struct mem_cgroup *root_mem) |
cdec2e42 KH |
2221 | { |
2222 | /* called when force_empty is called */ | |
d38144b7 | 2223 | drain_all_stock(root_mem, true); |
cdec2e42 KH |
2224 | } |
2225 | ||
711d3d2c KH |
2226 | /* |
2227 | * This function drains percpu counter value from DEAD cpu and | |
2228 | * move it to local cpu. Note that this function can be preempted. | |
2229 | */ | |
2230 | static void mem_cgroup_drain_pcp_counter(struct mem_cgroup *mem, int cpu) | |
2231 | { | |
2232 | int i; | |
2233 | ||
2234 | spin_lock(&mem->pcp_counter_lock); | |
2235 | for (i = 0; i < MEM_CGROUP_STAT_DATA; i++) { | |
7a159cc9 | 2236 | long x = per_cpu(mem->stat->count[i], cpu); |
711d3d2c KH |
2237 | |
2238 | per_cpu(mem->stat->count[i], cpu) = 0; | |
2239 | mem->nocpu_base.count[i] += x; | |
2240 | } | |
e9f8974f JW |
2241 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) { |
2242 | unsigned long x = per_cpu(mem->stat->events[i], cpu); | |
2243 | ||
2244 | per_cpu(mem->stat->events[i], cpu) = 0; | |
2245 | mem->nocpu_base.events[i] += x; | |
2246 | } | |
1489ebad KH |
2247 | /* need to clear ON_MOVE value, works as a kind of lock. */ |
2248 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) = 0; | |
2249 | spin_unlock(&mem->pcp_counter_lock); | |
2250 | } | |
2251 | ||
2252 | static void synchronize_mem_cgroup_on_move(struct mem_cgroup *mem, int cpu) | |
2253 | { | |
2254 | int idx = MEM_CGROUP_ON_MOVE; | |
2255 | ||
2256 | spin_lock(&mem->pcp_counter_lock); | |
2257 | per_cpu(mem->stat->count[idx], cpu) = mem->nocpu_base.count[idx]; | |
711d3d2c KH |
2258 | spin_unlock(&mem->pcp_counter_lock); |
2259 | } | |
2260 | ||
2261 | static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, | |
cdec2e42 KH |
2262 | unsigned long action, |
2263 | void *hcpu) | |
2264 | { | |
2265 | int cpu = (unsigned long)hcpu; | |
2266 | struct memcg_stock_pcp *stock; | |
711d3d2c | 2267 | struct mem_cgroup *iter; |
cdec2e42 | 2268 | |
1489ebad KH |
2269 | if ((action == CPU_ONLINE)) { |
2270 | for_each_mem_cgroup_all(iter) | |
2271 | synchronize_mem_cgroup_on_move(iter, cpu); | |
2272 | return NOTIFY_OK; | |
2273 | } | |
2274 | ||
711d3d2c | 2275 | if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN) |
cdec2e42 | 2276 | return NOTIFY_OK; |
711d3d2c KH |
2277 | |
2278 | for_each_mem_cgroup_all(iter) | |
2279 | mem_cgroup_drain_pcp_counter(iter, cpu); | |
2280 | ||
cdec2e42 KH |
2281 | stock = &per_cpu(memcg_stock, cpu); |
2282 | drain_stock(stock); | |
2283 | return NOTIFY_OK; | |
2284 | } | |
2285 | ||
4b534334 KH |
2286 | |
2287 | /* See __mem_cgroup_try_charge() for details */ | |
2288 | enum { | |
2289 | CHARGE_OK, /* success */ | |
2290 | CHARGE_RETRY, /* need to retry but retry is not bad */ | |
2291 | CHARGE_NOMEM, /* we can't do more. return -ENOMEM */ | |
2292 | CHARGE_WOULDBLOCK, /* GFP_WAIT wasn't set and no enough res. */ | |
2293 | CHARGE_OOM_DIE, /* the current is killed because of OOM */ | |
2294 | }; | |
2295 | ||
7ec99d62 JW |
2296 | static int mem_cgroup_do_charge(struct mem_cgroup *mem, gfp_t gfp_mask, |
2297 | unsigned int nr_pages, bool oom_check) | |
4b534334 | 2298 | { |
7ec99d62 | 2299 | unsigned long csize = nr_pages * PAGE_SIZE; |
4b534334 KH |
2300 | struct mem_cgroup *mem_over_limit; |
2301 | struct res_counter *fail_res; | |
2302 | unsigned long flags = 0; | |
2303 | int ret; | |
2304 | ||
2305 | ret = res_counter_charge(&mem->res, csize, &fail_res); | |
2306 | ||
2307 | if (likely(!ret)) { | |
2308 | if (!do_swap_account) | |
2309 | return CHARGE_OK; | |
2310 | ret = res_counter_charge(&mem->memsw, csize, &fail_res); | |
2311 | if (likely(!ret)) | |
2312 | return CHARGE_OK; | |
2313 | ||
01c88e2d | 2314 | res_counter_uncharge(&mem->res, csize); |
4b534334 KH |
2315 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw); |
2316 | flags |= MEM_CGROUP_RECLAIM_NOSWAP; | |
2317 | } else | |
2318 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, res); | |
9221edb7 | 2319 | /* |
7ec99d62 JW |
2320 | * nr_pages can be either a huge page (HPAGE_PMD_NR), a batch |
2321 | * of regular pages (CHARGE_BATCH), or a single regular page (1). | |
9221edb7 JW |
2322 | * |
2323 | * Never reclaim on behalf of optional batching, retry with a | |
2324 | * single page instead. | |
2325 | */ | |
7ec99d62 | 2326 | if (nr_pages == CHARGE_BATCH) |
4b534334 KH |
2327 | return CHARGE_RETRY; |
2328 | ||
2329 | if (!(gfp_mask & __GFP_WAIT)) | |
2330 | return CHARGE_WOULDBLOCK; | |
2331 | ||
2332 | ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, NULL, | |
0ae5e89c | 2333 | gfp_mask, flags, NULL); |
7ec99d62 | 2334 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
19942822 | 2335 | return CHARGE_RETRY; |
4b534334 | 2336 | /* |
19942822 JW |
2337 | * Even though the limit is exceeded at this point, reclaim |
2338 | * may have been able to free some pages. Retry the charge | |
2339 | * before killing the task. | |
2340 | * | |
2341 | * Only for regular pages, though: huge pages are rather | |
2342 | * unlikely to succeed so close to the limit, and we fall back | |
2343 | * to regular pages anyway in case of failure. | |
4b534334 | 2344 | */ |
7ec99d62 | 2345 | if (nr_pages == 1 && ret) |
4b534334 KH |
2346 | return CHARGE_RETRY; |
2347 | ||
2348 | /* | |
2349 | * At task move, charge accounts can be doubly counted. So, it's | |
2350 | * better to wait until the end of task_move if something is going on. | |
2351 | */ | |
2352 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2353 | return CHARGE_RETRY; | |
2354 | ||
2355 | /* If we don't need to call oom-killer at el, return immediately */ | |
2356 | if (!oom_check) | |
2357 | return CHARGE_NOMEM; | |
2358 | /* check OOM */ | |
2359 | if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask)) | |
2360 | return CHARGE_OOM_DIE; | |
2361 | ||
2362 | return CHARGE_RETRY; | |
2363 | } | |
2364 | ||
f817ed48 KH |
2365 | /* |
2366 | * Unlike exported interface, "oom" parameter is added. if oom==true, | |
2367 | * oom-killer can be invoked. | |
8a9f3ccd | 2368 | */ |
f817ed48 | 2369 | static int __mem_cgroup_try_charge(struct mm_struct *mm, |
ec168510 | 2370 | gfp_t gfp_mask, |
7ec99d62 JW |
2371 | unsigned int nr_pages, |
2372 | struct mem_cgroup **memcg, | |
2373 | bool oom) | |
8a9f3ccd | 2374 | { |
7ec99d62 | 2375 | unsigned int batch = max(CHARGE_BATCH, nr_pages); |
4b534334 KH |
2376 | int nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; |
2377 | struct mem_cgroup *mem = NULL; | |
2378 | int ret; | |
a636b327 | 2379 | |
867578cb KH |
2380 | /* |
2381 | * Unlike gloval-vm's OOM-kill, we're not in memory shortage | |
2382 | * in system level. So, allow to go ahead dying process in addition to | |
2383 | * MEMDIE process. | |
2384 | */ | |
2385 | if (unlikely(test_thread_flag(TIF_MEMDIE) | |
2386 | || fatal_signal_pending(current))) | |
2387 | goto bypass; | |
a636b327 | 2388 | |
8a9f3ccd | 2389 | /* |
3be91277 HD |
2390 | * We always charge the cgroup the mm_struct belongs to. |
2391 | * The mm_struct's mem_cgroup changes on task migration if the | |
8a9f3ccd BS |
2392 | * thread group leader migrates. It's possible that mm is not |
2393 | * set, if so charge the init_mm (happens for pagecache usage). | |
2394 | */ | |
f75ca962 KH |
2395 | if (!*memcg && !mm) |
2396 | goto bypass; | |
2397 | again: | |
2398 | if (*memcg) { /* css should be a valid one */ | |
4b534334 | 2399 | mem = *memcg; |
f75ca962 KH |
2400 | VM_BUG_ON(css_is_removed(&mem->css)); |
2401 | if (mem_cgroup_is_root(mem)) | |
2402 | goto done; | |
7ec99d62 | 2403 | if (nr_pages == 1 && consume_stock(mem)) |
f75ca962 | 2404 | goto done; |
4b534334 KH |
2405 | css_get(&mem->css); |
2406 | } else { | |
f75ca962 | 2407 | struct task_struct *p; |
54595fe2 | 2408 | |
f75ca962 KH |
2409 | rcu_read_lock(); |
2410 | p = rcu_dereference(mm->owner); | |
f75ca962 | 2411 | /* |
ebb76ce1 KH |
2412 | * Because we don't have task_lock(), "p" can exit. |
2413 | * In that case, "mem" can point to root or p can be NULL with | |
2414 | * race with swapoff. Then, we have small risk of mis-accouning. | |
2415 | * But such kind of mis-account by race always happens because | |
2416 | * we don't have cgroup_mutex(). It's overkill and we allo that | |
2417 | * small race, here. | |
2418 | * (*) swapoff at el will charge against mm-struct not against | |
2419 | * task-struct. So, mm->owner can be NULL. | |
f75ca962 KH |
2420 | */ |
2421 | mem = mem_cgroup_from_task(p); | |
ebb76ce1 | 2422 | if (!mem || mem_cgroup_is_root(mem)) { |
f75ca962 KH |
2423 | rcu_read_unlock(); |
2424 | goto done; | |
2425 | } | |
7ec99d62 | 2426 | if (nr_pages == 1 && consume_stock(mem)) { |
f75ca962 KH |
2427 | /* |
2428 | * It seems dagerous to access memcg without css_get(). | |
2429 | * But considering how consume_stok works, it's not | |
2430 | * necessary. If consume_stock success, some charges | |
2431 | * from this memcg are cached on this cpu. So, we | |
2432 | * don't need to call css_get()/css_tryget() before | |
2433 | * calling consume_stock(). | |
2434 | */ | |
2435 | rcu_read_unlock(); | |
2436 | goto done; | |
2437 | } | |
2438 | /* after here, we may be blocked. we need to get refcnt */ | |
2439 | if (!css_tryget(&mem->css)) { | |
2440 | rcu_read_unlock(); | |
2441 | goto again; | |
2442 | } | |
2443 | rcu_read_unlock(); | |
2444 | } | |
8a9f3ccd | 2445 | |
4b534334 KH |
2446 | do { |
2447 | bool oom_check; | |
7a81b88c | 2448 | |
4b534334 | 2449 | /* If killed, bypass charge */ |
f75ca962 KH |
2450 | if (fatal_signal_pending(current)) { |
2451 | css_put(&mem->css); | |
4b534334 | 2452 | goto bypass; |
f75ca962 | 2453 | } |
6d61ef40 | 2454 | |
4b534334 KH |
2455 | oom_check = false; |
2456 | if (oom && !nr_oom_retries) { | |
2457 | oom_check = true; | |
2458 | nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
cdec2e42 | 2459 | } |
66e1707b | 2460 | |
7ec99d62 | 2461 | ret = mem_cgroup_do_charge(mem, gfp_mask, batch, oom_check); |
4b534334 KH |
2462 | switch (ret) { |
2463 | case CHARGE_OK: | |
2464 | break; | |
2465 | case CHARGE_RETRY: /* not in OOM situation but retry */ | |
7ec99d62 | 2466 | batch = nr_pages; |
f75ca962 KH |
2467 | css_put(&mem->css); |
2468 | mem = NULL; | |
2469 | goto again; | |
4b534334 | 2470 | case CHARGE_WOULDBLOCK: /* !__GFP_WAIT */ |
f75ca962 | 2471 | css_put(&mem->css); |
4b534334 KH |
2472 | goto nomem; |
2473 | case CHARGE_NOMEM: /* OOM routine works */ | |
f75ca962 KH |
2474 | if (!oom) { |
2475 | css_put(&mem->css); | |
867578cb | 2476 | goto nomem; |
f75ca962 | 2477 | } |
4b534334 KH |
2478 | /* If oom, we never return -ENOMEM */ |
2479 | nr_oom_retries--; | |
2480 | break; | |
2481 | case CHARGE_OOM_DIE: /* Killed by OOM Killer */ | |
f75ca962 | 2482 | css_put(&mem->css); |
867578cb | 2483 | goto bypass; |
66e1707b | 2484 | } |
4b534334 KH |
2485 | } while (ret != CHARGE_OK); |
2486 | ||
7ec99d62 JW |
2487 | if (batch > nr_pages) |
2488 | refill_stock(mem, batch - nr_pages); | |
f75ca962 | 2489 | css_put(&mem->css); |
0c3e73e8 | 2490 | done: |
f75ca962 | 2491 | *memcg = mem; |
7a81b88c KH |
2492 | return 0; |
2493 | nomem: | |
f75ca962 | 2494 | *memcg = NULL; |
7a81b88c | 2495 | return -ENOMEM; |
867578cb KH |
2496 | bypass: |
2497 | *memcg = NULL; | |
2498 | return 0; | |
7a81b88c | 2499 | } |
8a9f3ccd | 2500 | |
a3032a2c DN |
2501 | /* |
2502 | * Somemtimes we have to undo a charge we got by try_charge(). | |
2503 | * This function is for that and do uncharge, put css's refcnt. | |
2504 | * gotten by try_charge(). | |
2505 | */ | |
854ffa8d | 2506 | static void __mem_cgroup_cancel_charge(struct mem_cgroup *mem, |
e7018b8d | 2507 | unsigned int nr_pages) |
a3032a2c DN |
2508 | { |
2509 | if (!mem_cgroup_is_root(mem)) { | |
e7018b8d JW |
2510 | unsigned long bytes = nr_pages * PAGE_SIZE; |
2511 | ||
2512 | res_counter_uncharge(&mem->res, bytes); | |
a3032a2c | 2513 | if (do_swap_account) |
e7018b8d | 2514 | res_counter_uncharge(&mem->memsw, bytes); |
a3032a2c | 2515 | } |
854ffa8d DN |
2516 | } |
2517 | ||
a3b2d692 KH |
2518 | /* |
2519 | * A helper function to get mem_cgroup from ID. must be called under | |
2520 | * rcu_read_lock(). The caller must check css_is_removed() or some if | |
2521 | * it's concern. (dropping refcnt from swap can be called against removed | |
2522 | * memcg.) | |
2523 | */ | |
2524 | static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) | |
2525 | { | |
2526 | struct cgroup_subsys_state *css; | |
2527 | ||
2528 | /* ID 0 is unused ID */ | |
2529 | if (!id) | |
2530 | return NULL; | |
2531 | css = css_lookup(&mem_cgroup_subsys, id); | |
2532 | if (!css) | |
2533 | return NULL; | |
2534 | return container_of(css, struct mem_cgroup, css); | |
2535 | } | |
2536 | ||
e42d9d5d | 2537 | struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) |
b5a84319 | 2538 | { |
e42d9d5d | 2539 | struct mem_cgroup *mem = NULL; |
3c776e64 | 2540 | struct page_cgroup *pc; |
a3b2d692 | 2541 | unsigned short id; |
b5a84319 KH |
2542 | swp_entry_t ent; |
2543 | ||
3c776e64 DN |
2544 | VM_BUG_ON(!PageLocked(page)); |
2545 | ||
3c776e64 | 2546 | pc = lookup_page_cgroup(page); |
c0bd3f63 | 2547 | lock_page_cgroup(pc); |
a3b2d692 | 2548 | if (PageCgroupUsed(pc)) { |
3c776e64 | 2549 | mem = pc->mem_cgroup; |
a3b2d692 KH |
2550 | if (mem && !css_tryget(&mem->css)) |
2551 | mem = NULL; | |
e42d9d5d | 2552 | } else if (PageSwapCache(page)) { |
3c776e64 | 2553 | ent.val = page_private(page); |
a3b2d692 KH |
2554 | id = lookup_swap_cgroup(ent); |
2555 | rcu_read_lock(); | |
2556 | mem = mem_cgroup_lookup(id); | |
2557 | if (mem && !css_tryget(&mem->css)) | |
2558 | mem = NULL; | |
2559 | rcu_read_unlock(); | |
3c776e64 | 2560 | } |
c0bd3f63 | 2561 | unlock_page_cgroup(pc); |
b5a84319 KH |
2562 | return mem; |
2563 | } | |
2564 | ||
ca3e0214 | 2565 | static void __mem_cgroup_commit_charge(struct mem_cgroup *mem, |
5564e88b | 2566 | struct page *page, |
7ec99d62 | 2567 | unsigned int nr_pages, |
ca3e0214 | 2568 | struct page_cgroup *pc, |
7ec99d62 | 2569 | enum charge_type ctype) |
7a81b88c | 2570 | { |
ca3e0214 KH |
2571 | lock_page_cgroup(pc); |
2572 | if (unlikely(PageCgroupUsed(pc))) { | |
2573 | unlock_page_cgroup(pc); | |
e7018b8d | 2574 | __mem_cgroup_cancel_charge(mem, nr_pages); |
ca3e0214 KH |
2575 | return; |
2576 | } | |
2577 | /* | |
2578 | * we don't need page_cgroup_lock about tail pages, becase they are not | |
2579 | * accessed by any other context at this point. | |
2580 | */ | |
8a9f3ccd | 2581 | pc->mem_cgroup = mem; |
261fb61a KH |
2582 | /* |
2583 | * We access a page_cgroup asynchronously without lock_page_cgroup(). | |
2584 | * Especially when a page_cgroup is taken from a page, pc->mem_cgroup | |
2585 | * is accessed after testing USED bit. To make pc->mem_cgroup visible | |
2586 | * before USED bit, we need memory barrier here. | |
2587 | * See mem_cgroup_add_lru_list(), etc. | |
2588 | */ | |
08e552c6 | 2589 | smp_wmb(); |
4b3bde4c BS |
2590 | switch (ctype) { |
2591 | case MEM_CGROUP_CHARGE_TYPE_CACHE: | |
2592 | case MEM_CGROUP_CHARGE_TYPE_SHMEM: | |
2593 | SetPageCgroupCache(pc); | |
2594 | SetPageCgroupUsed(pc); | |
2595 | break; | |
2596 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
2597 | ClearPageCgroupCache(pc); | |
2598 | SetPageCgroupUsed(pc); | |
2599 | break; | |
2600 | default: | |
2601 | break; | |
2602 | } | |
3be91277 | 2603 | |
ca3e0214 | 2604 | mem_cgroup_charge_statistics(mem, PageCgroupCache(pc), nr_pages); |
52d4b9ac | 2605 | unlock_page_cgroup(pc); |
430e4863 KH |
2606 | /* |
2607 | * "charge_statistics" updated event counter. Then, check it. | |
2608 | * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree. | |
2609 | * if they exceeds softlimit. | |
2610 | */ | |
5564e88b | 2611 | memcg_check_events(mem, page); |
7a81b88c | 2612 | } |
66e1707b | 2613 | |
ca3e0214 KH |
2614 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
2615 | ||
2616 | #define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) | (1 << PCG_MOVE_LOCK) |\ | |
2617 | (1 << PCG_ACCT_LRU) | (1 << PCG_MIGRATION)) | |
2618 | /* | |
2619 | * Because tail pages are not marked as "used", set it. We're under | |
2620 | * zone->lru_lock, 'splitting on pmd' and compund_lock. | |
2621 | */ | |
2622 | void mem_cgroup_split_huge_fixup(struct page *head, struct page *tail) | |
2623 | { | |
2624 | struct page_cgroup *head_pc = lookup_page_cgroup(head); | |
2625 | struct page_cgroup *tail_pc = lookup_page_cgroup(tail); | |
2626 | unsigned long flags; | |
2627 | ||
3d37c4a9 KH |
2628 | if (mem_cgroup_disabled()) |
2629 | return; | |
ca3e0214 | 2630 | /* |
ece35ca8 | 2631 | * We have no races with charge/uncharge but will have races with |
ca3e0214 KH |
2632 | * page state accounting. |
2633 | */ | |
2634 | move_lock_page_cgroup(head_pc, &flags); | |
2635 | ||
2636 | tail_pc->mem_cgroup = head_pc->mem_cgroup; | |
2637 | smp_wmb(); /* see __commit_charge() */ | |
ece35ca8 KH |
2638 | if (PageCgroupAcctLRU(head_pc)) { |
2639 | enum lru_list lru; | |
2640 | struct mem_cgroup_per_zone *mz; | |
2641 | ||
2642 | /* | |
2643 | * LRU flags cannot be copied because we need to add tail | |
2644 | *.page to LRU by generic call and our hook will be called. | |
2645 | * We hold lru_lock, then, reduce counter directly. | |
2646 | */ | |
2647 | lru = page_lru(head); | |
97a6c37b | 2648 | mz = page_cgroup_zoneinfo(head_pc->mem_cgroup, head); |
ece35ca8 KH |
2649 | MEM_CGROUP_ZSTAT(mz, lru) -= 1; |
2650 | } | |
ca3e0214 KH |
2651 | tail_pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT; |
2652 | move_unlock_page_cgroup(head_pc, &flags); | |
2653 | } | |
2654 | #endif | |
2655 | ||
f817ed48 | 2656 | /** |
de3638d9 | 2657 | * mem_cgroup_move_account - move account of the page |
5564e88b | 2658 | * @page: the page |
7ec99d62 | 2659 | * @nr_pages: number of regular pages (>1 for huge pages) |
f817ed48 KH |
2660 | * @pc: page_cgroup of the page. |
2661 | * @from: mem_cgroup which the page is moved from. | |
2662 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
854ffa8d | 2663 | * @uncharge: whether we should call uncharge and css_put against @from. |
f817ed48 KH |
2664 | * |
2665 | * The caller must confirm following. | |
08e552c6 | 2666 | * - page is not on LRU (isolate_page() is useful.) |
7ec99d62 | 2667 | * - compound_lock is held when nr_pages > 1 |
f817ed48 | 2668 | * |
854ffa8d | 2669 | * This function doesn't do "charge" nor css_get to new cgroup. It should be |
25985edc | 2670 | * done by a caller(__mem_cgroup_try_charge would be useful). If @uncharge is |
854ffa8d DN |
2671 | * true, this function does "uncharge" from old cgroup, but it doesn't if |
2672 | * @uncharge is false, so a caller should do "uncharge". | |
f817ed48 | 2673 | */ |
7ec99d62 JW |
2674 | static int mem_cgroup_move_account(struct page *page, |
2675 | unsigned int nr_pages, | |
2676 | struct page_cgroup *pc, | |
2677 | struct mem_cgroup *from, | |
2678 | struct mem_cgroup *to, | |
2679 | bool uncharge) | |
f817ed48 | 2680 | { |
de3638d9 JW |
2681 | unsigned long flags; |
2682 | int ret; | |
987eba66 | 2683 | |
f817ed48 | 2684 | VM_BUG_ON(from == to); |
5564e88b | 2685 | VM_BUG_ON(PageLRU(page)); |
de3638d9 JW |
2686 | /* |
2687 | * The page is isolated from LRU. So, collapse function | |
2688 | * will not handle this page. But page splitting can happen. | |
2689 | * Do this check under compound_page_lock(). The caller should | |
2690 | * hold it. | |
2691 | */ | |
2692 | ret = -EBUSY; | |
7ec99d62 | 2693 | if (nr_pages > 1 && !PageTransHuge(page)) |
de3638d9 JW |
2694 | goto out; |
2695 | ||
2696 | lock_page_cgroup(pc); | |
2697 | ||
2698 | ret = -EINVAL; | |
2699 | if (!PageCgroupUsed(pc) || pc->mem_cgroup != from) | |
2700 | goto unlock; | |
2701 | ||
2702 | move_lock_page_cgroup(pc, &flags); | |
f817ed48 | 2703 | |
8725d541 | 2704 | if (PageCgroupFileMapped(pc)) { |
c62b1a3b KH |
2705 | /* Update mapped_file data for mem_cgroup */ |
2706 | preempt_disable(); | |
2707 | __this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2708 | __this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2709 | preempt_enable(); | |
d69b042f | 2710 | } |
987eba66 | 2711 | mem_cgroup_charge_statistics(from, PageCgroupCache(pc), -nr_pages); |
854ffa8d DN |
2712 | if (uncharge) |
2713 | /* This is not "cancel", but cancel_charge does all we need. */ | |
e7018b8d | 2714 | __mem_cgroup_cancel_charge(from, nr_pages); |
d69b042f | 2715 | |
854ffa8d | 2716 | /* caller should have done css_get */ |
08e552c6 | 2717 | pc->mem_cgroup = to; |
987eba66 | 2718 | mem_cgroup_charge_statistics(to, PageCgroupCache(pc), nr_pages); |
88703267 KH |
2719 | /* |
2720 | * We charges against "to" which may not have any tasks. Then, "to" | |
2721 | * can be under rmdir(). But in current implementation, caller of | |
4ffef5fe | 2722 | * this function is just force_empty() and move charge, so it's |
25985edc | 2723 | * guaranteed that "to" is never removed. So, we don't check rmdir |
4ffef5fe | 2724 | * status here. |
88703267 | 2725 | */ |
de3638d9 JW |
2726 | move_unlock_page_cgroup(pc, &flags); |
2727 | ret = 0; | |
2728 | unlock: | |
57f9fd7d | 2729 | unlock_page_cgroup(pc); |
d2265e6f KH |
2730 | /* |
2731 | * check events | |
2732 | */ | |
5564e88b JW |
2733 | memcg_check_events(to, page); |
2734 | memcg_check_events(from, page); | |
de3638d9 | 2735 | out: |
f817ed48 KH |
2736 | return ret; |
2737 | } | |
2738 | ||
2739 | /* | |
2740 | * move charges to its parent. | |
2741 | */ | |
2742 | ||
5564e88b JW |
2743 | static int mem_cgroup_move_parent(struct page *page, |
2744 | struct page_cgroup *pc, | |
f817ed48 KH |
2745 | struct mem_cgroup *child, |
2746 | gfp_t gfp_mask) | |
2747 | { | |
2748 | struct cgroup *cg = child->css.cgroup; | |
2749 | struct cgroup *pcg = cg->parent; | |
2750 | struct mem_cgroup *parent; | |
7ec99d62 | 2751 | unsigned int nr_pages; |
4be4489f | 2752 | unsigned long uninitialized_var(flags); |
f817ed48 KH |
2753 | int ret; |
2754 | ||
2755 | /* Is ROOT ? */ | |
2756 | if (!pcg) | |
2757 | return -EINVAL; | |
2758 | ||
57f9fd7d DN |
2759 | ret = -EBUSY; |
2760 | if (!get_page_unless_zero(page)) | |
2761 | goto out; | |
2762 | if (isolate_lru_page(page)) | |
2763 | goto put; | |
52dbb905 | 2764 | |
7ec99d62 | 2765 | nr_pages = hpage_nr_pages(page); |
08e552c6 | 2766 | |
f817ed48 | 2767 | parent = mem_cgroup_from_cont(pcg); |
7ec99d62 | 2768 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, nr_pages, &parent, false); |
a636b327 | 2769 | if (ret || !parent) |
57f9fd7d | 2770 | goto put_back; |
f817ed48 | 2771 | |
7ec99d62 | 2772 | if (nr_pages > 1) |
987eba66 KH |
2773 | flags = compound_lock_irqsave(page); |
2774 | ||
7ec99d62 | 2775 | ret = mem_cgroup_move_account(page, nr_pages, pc, child, parent, true); |
854ffa8d | 2776 | if (ret) |
7ec99d62 | 2777 | __mem_cgroup_cancel_charge(parent, nr_pages); |
8dba474f | 2778 | |
7ec99d62 | 2779 | if (nr_pages > 1) |
987eba66 | 2780 | compound_unlock_irqrestore(page, flags); |
8dba474f | 2781 | put_back: |
08e552c6 | 2782 | putback_lru_page(page); |
57f9fd7d | 2783 | put: |
40d58138 | 2784 | put_page(page); |
57f9fd7d | 2785 | out: |
f817ed48 KH |
2786 | return ret; |
2787 | } | |
2788 | ||
7a81b88c KH |
2789 | /* |
2790 | * Charge the memory controller for page usage. | |
2791 | * Return | |
2792 | * 0 if the charge was successful | |
2793 | * < 0 if the cgroup is over its limit | |
2794 | */ | |
2795 | static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, | |
73045c47 | 2796 | gfp_t gfp_mask, enum charge_type ctype) |
7a81b88c | 2797 | { |
73045c47 | 2798 | struct mem_cgroup *mem = NULL; |
7ec99d62 | 2799 | unsigned int nr_pages = 1; |
7a81b88c | 2800 | struct page_cgroup *pc; |
8493ae43 | 2801 | bool oom = true; |
7a81b88c | 2802 | int ret; |
ec168510 | 2803 | |
37c2ac78 | 2804 | if (PageTransHuge(page)) { |
7ec99d62 | 2805 | nr_pages <<= compound_order(page); |
37c2ac78 | 2806 | VM_BUG_ON(!PageTransHuge(page)); |
8493ae43 JW |
2807 | /* |
2808 | * Never OOM-kill a process for a huge page. The | |
2809 | * fault handler will fall back to regular pages. | |
2810 | */ | |
2811 | oom = false; | |
37c2ac78 | 2812 | } |
7a81b88c KH |
2813 | |
2814 | pc = lookup_page_cgroup(page); | |
af4a6621 | 2815 | BUG_ON(!pc); /* XXX: remove this and move pc lookup into commit */ |
7a81b88c | 2816 | |
7ec99d62 | 2817 | ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &mem, oom); |
a636b327 | 2818 | if (ret || !mem) |
7a81b88c KH |
2819 | return ret; |
2820 | ||
7ec99d62 | 2821 | __mem_cgroup_commit_charge(mem, page, nr_pages, pc, ctype); |
8a9f3ccd | 2822 | return 0; |
8a9f3ccd BS |
2823 | } |
2824 | ||
7a81b88c KH |
2825 | int mem_cgroup_newpage_charge(struct page *page, |
2826 | struct mm_struct *mm, gfp_t gfp_mask) | |
217bc319 | 2827 | { |
f8d66542 | 2828 | if (mem_cgroup_disabled()) |
cede86ac | 2829 | return 0; |
69029cd5 KH |
2830 | /* |
2831 | * If already mapped, we don't have to account. | |
2832 | * If page cache, page->mapping has address_space. | |
2833 | * But page->mapping may have out-of-use anon_vma pointer, | |
2834 | * detecit it by PageAnon() check. newly-mapped-anon's page->mapping | |
2835 | * is NULL. | |
2836 | */ | |
2837 | if (page_mapped(page) || (page->mapping && !PageAnon(page))) | |
2838 | return 0; | |
2839 | if (unlikely(!mm)) | |
2840 | mm = &init_mm; | |
217bc319 | 2841 | return mem_cgroup_charge_common(page, mm, gfp_mask, |
73045c47 | 2842 | MEM_CGROUP_CHARGE_TYPE_MAPPED); |
217bc319 KH |
2843 | } |
2844 | ||
83aae4c7 DN |
2845 | static void |
2846 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
2847 | enum charge_type ctype); | |
2848 | ||
5a6475a4 KH |
2849 | static void |
2850 | __mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *mem, | |
2851 | enum charge_type ctype) | |
2852 | { | |
2853 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
2854 | /* | |
2855 | * In some case, SwapCache, FUSE(splice_buf->radixtree), the page | |
2856 | * is already on LRU. It means the page may on some other page_cgroup's | |
2857 | * LRU. Take care of it. | |
2858 | */ | |
2859 | mem_cgroup_lru_del_before_commit(page); | |
2860 | __mem_cgroup_commit_charge(mem, page, 1, pc, ctype); | |
2861 | mem_cgroup_lru_add_after_commit(page); | |
2862 | return; | |
2863 | } | |
2864 | ||
e1a1cd59 BS |
2865 | int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, |
2866 | gfp_t gfp_mask) | |
8697d331 | 2867 | { |
5a6475a4 | 2868 | struct mem_cgroup *mem = NULL; |
b5a84319 KH |
2869 | int ret; |
2870 | ||
f8d66542 | 2871 | if (mem_cgroup_disabled()) |
cede86ac | 2872 | return 0; |
52d4b9ac KH |
2873 | if (PageCompound(page)) |
2874 | return 0; | |
accf163e | 2875 | |
73045c47 | 2876 | if (unlikely(!mm)) |
8697d331 | 2877 | mm = &init_mm; |
accf163e | 2878 | |
5a6475a4 KH |
2879 | if (page_is_file_cache(page)) { |
2880 | ret = __mem_cgroup_try_charge(mm, gfp_mask, 1, &mem, true); | |
2881 | if (ret || !mem) | |
2882 | return ret; | |
b5a84319 | 2883 | |
5a6475a4 KH |
2884 | /* |
2885 | * FUSE reuses pages without going through the final | |
2886 | * put that would remove them from the LRU list, make | |
2887 | * sure that they get relinked properly. | |
2888 | */ | |
2889 | __mem_cgroup_commit_charge_lrucare(page, mem, | |
2890 | MEM_CGROUP_CHARGE_TYPE_CACHE); | |
2891 | return ret; | |
2892 | } | |
83aae4c7 DN |
2893 | /* shmem */ |
2894 | if (PageSwapCache(page)) { | |
2895 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); | |
2896 | if (!ret) | |
2897 | __mem_cgroup_commit_charge_swapin(page, mem, | |
2898 | MEM_CGROUP_CHARGE_TYPE_SHMEM); | |
2899 | } else | |
2900 | ret = mem_cgroup_charge_common(page, mm, gfp_mask, | |
73045c47 | 2901 | MEM_CGROUP_CHARGE_TYPE_SHMEM); |
b5a84319 | 2902 | |
b5a84319 | 2903 | return ret; |
e8589cc1 KH |
2904 | } |
2905 | ||
54595fe2 KH |
2906 | /* |
2907 | * While swap-in, try_charge -> commit or cancel, the page is locked. | |
2908 | * And when try_charge() successfully returns, one refcnt to memcg without | |
21ae2956 | 2909 | * struct page_cgroup is acquired. This refcnt will be consumed by |
54595fe2 KH |
2910 | * "commit()" or removed by "cancel()" |
2911 | */ | |
8c7c6e34 KH |
2912 | int mem_cgroup_try_charge_swapin(struct mm_struct *mm, |
2913 | struct page *page, | |
2914 | gfp_t mask, struct mem_cgroup **ptr) | |
2915 | { | |
2916 | struct mem_cgroup *mem; | |
54595fe2 | 2917 | int ret; |
8c7c6e34 | 2918 | |
56039efa KH |
2919 | *ptr = NULL; |
2920 | ||
f8d66542 | 2921 | if (mem_cgroup_disabled()) |
8c7c6e34 KH |
2922 | return 0; |
2923 | ||
2924 | if (!do_swap_account) | |
2925 | goto charge_cur_mm; | |
8c7c6e34 KH |
2926 | /* |
2927 | * A racing thread's fault, or swapoff, may have already updated | |
407f9c8b HD |
2928 | * the pte, and even removed page from swap cache: in those cases |
2929 | * do_swap_page()'s pte_same() test will fail; but there's also a | |
2930 | * KSM case which does need to charge the page. | |
8c7c6e34 KH |
2931 | */ |
2932 | if (!PageSwapCache(page)) | |
407f9c8b | 2933 | goto charge_cur_mm; |
e42d9d5d | 2934 | mem = try_get_mem_cgroup_from_page(page); |
54595fe2 KH |
2935 | if (!mem) |
2936 | goto charge_cur_mm; | |
8c7c6e34 | 2937 | *ptr = mem; |
7ec99d62 | 2938 | ret = __mem_cgroup_try_charge(NULL, mask, 1, ptr, true); |
54595fe2 KH |
2939 | css_put(&mem->css); |
2940 | return ret; | |
8c7c6e34 KH |
2941 | charge_cur_mm: |
2942 | if (unlikely(!mm)) | |
2943 | mm = &init_mm; | |
7ec99d62 | 2944 | return __mem_cgroup_try_charge(mm, mask, 1, ptr, true); |
8c7c6e34 KH |
2945 | } |
2946 | ||
83aae4c7 DN |
2947 | static void |
2948 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
2949 | enum charge_type ctype) | |
7a81b88c | 2950 | { |
f8d66542 | 2951 | if (mem_cgroup_disabled()) |
7a81b88c KH |
2952 | return; |
2953 | if (!ptr) | |
2954 | return; | |
88703267 | 2955 | cgroup_exclude_rmdir(&ptr->css); |
5a6475a4 KH |
2956 | |
2957 | __mem_cgroup_commit_charge_lrucare(page, ptr, ctype); | |
8c7c6e34 KH |
2958 | /* |
2959 | * Now swap is on-memory. This means this page may be | |
2960 | * counted both as mem and swap....double count. | |
03f3c433 KH |
2961 | * Fix it by uncharging from memsw. Basically, this SwapCache is stable |
2962 | * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page() | |
2963 | * may call delete_from_swap_cache() before reach here. | |
8c7c6e34 | 2964 | */ |
03f3c433 | 2965 | if (do_swap_account && PageSwapCache(page)) { |
8c7c6e34 | 2966 | swp_entry_t ent = {.val = page_private(page)}; |
a3b2d692 | 2967 | unsigned short id; |
8c7c6e34 | 2968 | struct mem_cgroup *memcg; |
a3b2d692 KH |
2969 | |
2970 | id = swap_cgroup_record(ent, 0); | |
2971 | rcu_read_lock(); | |
2972 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 2973 | if (memcg) { |
a3b2d692 KH |
2974 | /* |
2975 | * This recorded memcg can be obsolete one. So, avoid | |
2976 | * calling css_tryget | |
2977 | */ | |
0c3e73e8 | 2978 | if (!mem_cgroup_is_root(memcg)) |
4e649152 | 2979 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
0c3e73e8 | 2980 | mem_cgroup_swap_statistics(memcg, false); |
8c7c6e34 KH |
2981 | mem_cgroup_put(memcg); |
2982 | } | |
a3b2d692 | 2983 | rcu_read_unlock(); |
8c7c6e34 | 2984 | } |
88703267 KH |
2985 | /* |
2986 | * At swapin, we may charge account against cgroup which has no tasks. | |
2987 | * So, rmdir()->pre_destroy() can be called while we do this charge. | |
2988 | * In that case, we need to call pre_destroy() again. check it here. | |
2989 | */ | |
2990 | cgroup_release_and_wakeup_rmdir(&ptr->css); | |
7a81b88c KH |
2991 | } |
2992 | ||
83aae4c7 DN |
2993 | void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) |
2994 | { | |
2995 | __mem_cgroup_commit_charge_swapin(page, ptr, | |
2996 | MEM_CGROUP_CHARGE_TYPE_MAPPED); | |
2997 | } | |
2998 | ||
7a81b88c KH |
2999 | void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem) |
3000 | { | |
f8d66542 | 3001 | if (mem_cgroup_disabled()) |
7a81b88c KH |
3002 | return; |
3003 | if (!mem) | |
3004 | return; | |
e7018b8d | 3005 | __mem_cgroup_cancel_charge(mem, 1); |
7a81b88c KH |
3006 | } |
3007 | ||
7ec99d62 JW |
3008 | static void mem_cgroup_do_uncharge(struct mem_cgroup *mem, |
3009 | unsigned int nr_pages, | |
3010 | const enum charge_type ctype) | |
569b846d KH |
3011 | { |
3012 | struct memcg_batch_info *batch = NULL; | |
3013 | bool uncharge_memsw = true; | |
7ec99d62 | 3014 | |
569b846d KH |
3015 | /* If swapout, usage of swap doesn't decrease */ |
3016 | if (!do_swap_account || ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) | |
3017 | uncharge_memsw = false; | |
569b846d KH |
3018 | |
3019 | batch = ¤t->memcg_batch; | |
3020 | /* | |
3021 | * In usual, we do css_get() when we remember memcg pointer. | |
3022 | * But in this case, we keep res->usage until end of a series of | |
3023 | * uncharges. Then, it's ok to ignore memcg's refcnt. | |
3024 | */ | |
3025 | if (!batch->memcg) | |
3026 | batch->memcg = mem; | |
3c11ecf4 KH |
3027 | /* |
3028 | * do_batch > 0 when unmapping pages or inode invalidate/truncate. | |
25985edc | 3029 | * In those cases, all pages freed continuously can be expected to be in |
3c11ecf4 KH |
3030 | * the same cgroup and we have chance to coalesce uncharges. |
3031 | * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE) | |
3032 | * because we want to do uncharge as soon as possible. | |
3033 | */ | |
3034 | ||
3035 | if (!batch->do_batch || test_thread_flag(TIF_MEMDIE)) | |
3036 | goto direct_uncharge; | |
3037 | ||
7ec99d62 | 3038 | if (nr_pages > 1) |
ec168510 AA |
3039 | goto direct_uncharge; |
3040 | ||
569b846d KH |
3041 | /* |
3042 | * In typical case, batch->memcg == mem. This means we can | |
3043 | * merge a series of uncharges to an uncharge of res_counter. | |
3044 | * If not, we uncharge res_counter ony by one. | |
3045 | */ | |
3046 | if (batch->memcg != mem) | |
3047 | goto direct_uncharge; | |
3048 | /* remember freed charge and uncharge it later */ | |
7ffd4ca7 | 3049 | batch->nr_pages++; |
569b846d | 3050 | if (uncharge_memsw) |
7ffd4ca7 | 3051 | batch->memsw_nr_pages++; |
569b846d KH |
3052 | return; |
3053 | direct_uncharge: | |
7ec99d62 | 3054 | res_counter_uncharge(&mem->res, nr_pages * PAGE_SIZE); |
569b846d | 3055 | if (uncharge_memsw) |
7ec99d62 | 3056 | res_counter_uncharge(&mem->memsw, nr_pages * PAGE_SIZE); |
3c11ecf4 KH |
3057 | if (unlikely(batch->memcg != mem)) |
3058 | memcg_oom_recover(mem); | |
569b846d KH |
3059 | return; |
3060 | } | |
7a81b88c | 3061 | |
8a9f3ccd | 3062 | /* |
69029cd5 | 3063 | * uncharge if !page_mapped(page) |
8a9f3ccd | 3064 | */ |
8c7c6e34 | 3065 | static struct mem_cgroup * |
69029cd5 | 3066 | __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) |
8a9f3ccd | 3067 | { |
8c7c6e34 | 3068 | struct mem_cgroup *mem = NULL; |
7ec99d62 JW |
3069 | unsigned int nr_pages = 1; |
3070 | struct page_cgroup *pc; | |
8a9f3ccd | 3071 | |
f8d66542 | 3072 | if (mem_cgroup_disabled()) |
8c7c6e34 | 3073 | return NULL; |
4077960e | 3074 | |
d13d1443 | 3075 | if (PageSwapCache(page)) |
8c7c6e34 | 3076 | return NULL; |
d13d1443 | 3077 | |
37c2ac78 | 3078 | if (PageTransHuge(page)) { |
7ec99d62 | 3079 | nr_pages <<= compound_order(page); |
37c2ac78 AA |
3080 | VM_BUG_ON(!PageTransHuge(page)); |
3081 | } | |
8697d331 | 3082 | /* |
3c541e14 | 3083 | * Check if our page_cgroup is valid |
8697d331 | 3084 | */ |
52d4b9ac KH |
3085 | pc = lookup_page_cgroup(page); |
3086 | if (unlikely(!pc || !PageCgroupUsed(pc))) | |
8c7c6e34 | 3087 | return NULL; |
b9c565d5 | 3088 | |
52d4b9ac | 3089 | lock_page_cgroup(pc); |
d13d1443 | 3090 | |
8c7c6e34 KH |
3091 | mem = pc->mem_cgroup; |
3092 | ||
d13d1443 KH |
3093 | if (!PageCgroupUsed(pc)) |
3094 | goto unlock_out; | |
3095 | ||
3096 | switch (ctype) { | |
3097 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
8a9478ca | 3098 | case MEM_CGROUP_CHARGE_TYPE_DROP: |
ac39cf8c | 3099 | /* See mem_cgroup_prepare_migration() */ |
3100 | if (page_mapped(page) || PageCgroupMigration(pc)) | |
d13d1443 KH |
3101 | goto unlock_out; |
3102 | break; | |
3103 | case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: | |
3104 | if (!PageAnon(page)) { /* Shared memory */ | |
3105 | if (page->mapping && !page_is_file_cache(page)) | |
3106 | goto unlock_out; | |
3107 | } else if (page_mapped(page)) /* Anon */ | |
3108 | goto unlock_out; | |
3109 | break; | |
3110 | default: | |
3111 | break; | |
52d4b9ac | 3112 | } |
d13d1443 | 3113 | |
7ec99d62 | 3114 | mem_cgroup_charge_statistics(mem, PageCgroupCache(pc), -nr_pages); |
04046e1a | 3115 | |
52d4b9ac | 3116 | ClearPageCgroupUsed(pc); |
544122e5 KH |
3117 | /* |
3118 | * pc->mem_cgroup is not cleared here. It will be accessed when it's | |
3119 | * freed from LRU. This is safe because uncharged page is expected not | |
3120 | * to be reused (freed soon). Exception is SwapCache, it's handled by | |
3121 | * special functions. | |
3122 | */ | |
b9c565d5 | 3123 | |
52d4b9ac | 3124 | unlock_page_cgroup(pc); |
f75ca962 KH |
3125 | /* |
3126 | * even after unlock, we have mem->res.usage here and this memcg | |
3127 | * will never be freed. | |
3128 | */ | |
d2265e6f | 3129 | memcg_check_events(mem, page); |
f75ca962 KH |
3130 | if (do_swap_account && ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) { |
3131 | mem_cgroup_swap_statistics(mem, true); | |
3132 | mem_cgroup_get(mem); | |
3133 | } | |
3134 | if (!mem_cgroup_is_root(mem)) | |
7ec99d62 | 3135 | mem_cgroup_do_uncharge(mem, nr_pages, ctype); |
6d12e2d8 | 3136 | |
8c7c6e34 | 3137 | return mem; |
d13d1443 KH |
3138 | |
3139 | unlock_out: | |
3140 | unlock_page_cgroup(pc); | |
8c7c6e34 | 3141 | return NULL; |
3c541e14 BS |
3142 | } |
3143 | ||
69029cd5 KH |
3144 | void mem_cgroup_uncharge_page(struct page *page) |
3145 | { | |
52d4b9ac KH |
3146 | /* early check. */ |
3147 | if (page_mapped(page)) | |
3148 | return; | |
3149 | if (page->mapping && !PageAnon(page)) | |
3150 | return; | |
69029cd5 KH |
3151 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED); |
3152 | } | |
3153 | ||
3154 | void mem_cgroup_uncharge_cache_page(struct page *page) | |
3155 | { | |
3156 | VM_BUG_ON(page_mapped(page)); | |
b7abea96 | 3157 | VM_BUG_ON(page->mapping); |
69029cd5 KH |
3158 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); |
3159 | } | |
3160 | ||
569b846d KH |
3161 | /* |
3162 | * Batch_start/batch_end is called in unmap_page_range/invlidate/trucate. | |
3163 | * In that cases, pages are freed continuously and we can expect pages | |
3164 | * are in the same memcg. All these calls itself limits the number of | |
3165 | * pages freed at once, then uncharge_start/end() is called properly. | |
3166 | * This may be called prural(2) times in a context, | |
3167 | */ | |
3168 | ||
3169 | void mem_cgroup_uncharge_start(void) | |
3170 | { | |
3171 | current->memcg_batch.do_batch++; | |
3172 | /* We can do nest. */ | |
3173 | if (current->memcg_batch.do_batch == 1) { | |
3174 | current->memcg_batch.memcg = NULL; | |
7ffd4ca7 JW |
3175 | current->memcg_batch.nr_pages = 0; |
3176 | current->memcg_batch.memsw_nr_pages = 0; | |
569b846d KH |
3177 | } |
3178 | } | |
3179 | ||
3180 | void mem_cgroup_uncharge_end(void) | |
3181 | { | |
3182 | struct memcg_batch_info *batch = ¤t->memcg_batch; | |
3183 | ||
3184 | if (!batch->do_batch) | |
3185 | return; | |
3186 | ||
3187 | batch->do_batch--; | |
3188 | if (batch->do_batch) /* If stacked, do nothing. */ | |
3189 | return; | |
3190 | ||
3191 | if (!batch->memcg) | |
3192 | return; | |
3193 | /* | |
3194 | * This "batch->memcg" is valid without any css_get/put etc... | |
3195 | * bacause we hide charges behind us. | |
3196 | */ | |
7ffd4ca7 JW |
3197 | if (batch->nr_pages) |
3198 | res_counter_uncharge(&batch->memcg->res, | |
3199 | batch->nr_pages * PAGE_SIZE); | |
3200 | if (batch->memsw_nr_pages) | |
3201 | res_counter_uncharge(&batch->memcg->memsw, | |
3202 | batch->memsw_nr_pages * PAGE_SIZE); | |
3c11ecf4 | 3203 | memcg_oom_recover(batch->memcg); |
569b846d KH |
3204 | /* forget this pointer (for sanity check) */ |
3205 | batch->memcg = NULL; | |
3206 | } | |
3207 | ||
e767e056 | 3208 | #ifdef CONFIG_SWAP |
8c7c6e34 | 3209 | /* |
e767e056 | 3210 | * called after __delete_from_swap_cache() and drop "page" account. |
8c7c6e34 KH |
3211 | * memcg information is recorded to swap_cgroup of "ent" |
3212 | */ | |
8a9478ca KH |
3213 | void |
3214 | mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout) | |
8c7c6e34 KH |
3215 | { |
3216 | struct mem_cgroup *memcg; | |
8a9478ca KH |
3217 | int ctype = MEM_CGROUP_CHARGE_TYPE_SWAPOUT; |
3218 | ||
3219 | if (!swapout) /* this was a swap cache but the swap is unused ! */ | |
3220 | ctype = MEM_CGROUP_CHARGE_TYPE_DROP; | |
3221 | ||
3222 | memcg = __mem_cgroup_uncharge_common(page, ctype); | |
8c7c6e34 | 3223 | |
f75ca962 KH |
3224 | /* |
3225 | * record memcg information, if swapout && memcg != NULL, | |
3226 | * mem_cgroup_get() was called in uncharge(). | |
3227 | */ | |
3228 | if (do_swap_account && swapout && memcg) | |
a3b2d692 | 3229 | swap_cgroup_record(ent, css_id(&memcg->css)); |
8c7c6e34 | 3230 | } |
e767e056 | 3231 | #endif |
8c7c6e34 KH |
3232 | |
3233 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
3234 | /* | |
3235 | * called from swap_entry_free(). remove record in swap_cgroup and | |
3236 | * uncharge "memsw" account. | |
3237 | */ | |
3238 | void mem_cgroup_uncharge_swap(swp_entry_t ent) | |
d13d1443 | 3239 | { |
8c7c6e34 | 3240 | struct mem_cgroup *memcg; |
a3b2d692 | 3241 | unsigned short id; |
8c7c6e34 KH |
3242 | |
3243 | if (!do_swap_account) | |
3244 | return; | |
3245 | ||
a3b2d692 KH |
3246 | id = swap_cgroup_record(ent, 0); |
3247 | rcu_read_lock(); | |
3248 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 3249 | if (memcg) { |
a3b2d692 KH |
3250 | /* |
3251 | * We uncharge this because swap is freed. | |
3252 | * This memcg can be obsolete one. We avoid calling css_tryget | |
3253 | */ | |
0c3e73e8 | 3254 | if (!mem_cgroup_is_root(memcg)) |
4e649152 | 3255 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
0c3e73e8 | 3256 | mem_cgroup_swap_statistics(memcg, false); |
8c7c6e34 KH |
3257 | mem_cgroup_put(memcg); |
3258 | } | |
a3b2d692 | 3259 | rcu_read_unlock(); |
d13d1443 | 3260 | } |
02491447 DN |
3261 | |
3262 | /** | |
3263 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
3264 | * @entry: swap entry to be moved | |
3265 | * @from: mem_cgroup which the entry is moved from | |
3266 | * @to: mem_cgroup which the entry is moved to | |
483c30b5 | 3267 | * @need_fixup: whether we should fixup res_counters and refcounts. |
02491447 DN |
3268 | * |
3269 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
3270 | * as the mem_cgroup's id of @from. | |
3271 | * | |
3272 | * Returns 0 on success, -EINVAL on failure. | |
3273 | * | |
3274 | * The caller must have charged to @to, IOW, called res_counter_charge() about | |
3275 | * both res and memsw, and called css_get(). | |
3276 | */ | |
3277 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
483c30b5 | 3278 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
02491447 DN |
3279 | { |
3280 | unsigned short old_id, new_id; | |
3281 | ||
3282 | old_id = css_id(&from->css); | |
3283 | new_id = css_id(&to->css); | |
3284 | ||
3285 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
02491447 | 3286 | mem_cgroup_swap_statistics(from, false); |
483c30b5 | 3287 | mem_cgroup_swap_statistics(to, true); |
02491447 | 3288 | /* |
483c30b5 DN |
3289 | * This function is only called from task migration context now. |
3290 | * It postpones res_counter and refcount handling till the end | |
3291 | * of task migration(mem_cgroup_clear_mc()) for performance | |
3292 | * improvement. But we cannot postpone mem_cgroup_get(to) | |
3293 | * because if the process that has been moved to @to does | |
3294 | * swap-in, the refcount of @to might be decreased to 0. | |
02491447 | 3295 | */ |
02491447 | 3296 | mem_cgroup_get(to); |
483c30b5 DN |
3297 | if (need_fixup) { |
3298 | if (!mem_cgroup_is_root(from)) | |
3299 | res_counter_uncharge(&from->memsw, PAGE_SIZE); | |
3300 | mem_cgroup_put(from); | |
3301 | /* | |
3302 | * we charged both to->res and to->memsw, so we should | |
3303 | * uncharge to->res. | |
3304 | */ | |
3305 | if (!mem_cgroup_is_root(to)) | |
3306 | res_counter_uncharge(&to->res, PAGE_SIZE); | |
483c30b5 | 3307 | } |
02491447 DN |
3308 | return 0; |
3309 | } | |
3310 | return -EINVAL; | |
3311 | } | |
3312 | #else | |
3313 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
483c30b5 | 3314 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
02491447 DN |
3315 | { |
3316 | return -EINVAL; | |
3317 | } | |
8c7c6e34 | 3318 | #endif |
d13d1443 | 3319 | |
ae41be37 | 3320 | /* |
01b1ae63 KH |
3321 | * Before starting migration, account PAGE_SIZE to mem_cgroup that the old |
3322 | * page belongs to. | |
ae41be37 | 3323 | */ |
ac39cf8c | 3324 | int mem_cgroup_prepare_migration(struct page *page, |
ef6a3c63 | 3325 | struct page *newpage, struct mem_cgroup **ptr, gfp_t gfp_mask) |
ae41be37 | 3326 | { |
e8589cc1 | 3327 | struct mem_cgroup *mem = NULL; |
7ec99d62 | 3328 | struct page_cgroup *pc; |
ac39cf8c | 3329 | enum charge_type ctype; |
e8589cc1 | 3330 | int ret = 0; |
8869b8f6 | 3331 | |
56039efa KH |
3332 | *ptr = NULL; |
3333 | ||
ec168510 | 3334 | VM_BUG_ON(PageTransHuge(page)); |
f8d66542 | 3335 | if (mem_cgroup_disabled()) |
4077960e BS |
3336 | return 0; |
3337 | ||
52d4b9ac KH |
3338 | pc = lookup_page_cgroup(page); |
3339 | lock_page_cgroup(pc); | |
3340 | if (PageCgroupUsed(pc)) { | |
e8589cc1 KH |
3341 | mem = pc->mem_cgroup; |
3342 | css_get(&mem->css); | |
ac39cf8c | 3343 | /* |
3344 | * At migrating an anonymous page, its mapcount goes down | |
3345 | * to 0 and uncharge() will be called. But, even if it's fully | |
3346 | * unmapped, migration may fail and this page has to be | |
3347 | * charged again. We set MIGRATION flag here and delay uncharge | |
3348 | * until end_migration() is called | |
3349 | * | |
3350 | * Corner Case Thinking | |
3351 | * A) | |
3352 | * When the old page was mapped as Anon and it's unmap-and-freed | |
3353 | * while migration was ongoing. | |
3354 | * If unmap finds the old page, uncharge() of it will be delayed | |
3355 | * until end_migration(). If unmap finds a new page, it's | |
3356 | * uncharged when it make mapcount to be 1->0. If unmap code | |
3357 | * finds swap_migration_entry, the new page will not be mapped | |
3358 | * and end_migration() will find it(mapcount==0). | |
3359 | * | |
3360 | * B) | |
3361 | * When the old page was mapped but migraion fails, the kernel | |
3362 | * remaps it. A charge for it is kept by MIGRATION flag even | |
3363 | * if mapcount goes down to 0. We can do remap successfully | |
3364 | * without charging it again. | |
3365 | * | |
3366 | * C) | |
3367 | * The "old" page is under lock_page() until the end of | |
3368 | * migration, so, the old page itself will not be swapped-out. | |
3369 | * If the new page is swapped out before end_migraton, our | |
3370 | * hook to usual swap-out path will catch the event. | |
3371 | */ | |
3372 | if (PageAnon(page)) | |
3373 | SetPageCgroupMigration(pc); | |
e8589cc1 | 3374 | } |
52d4b9ac | 3375 | unlock_page_cgroup(pc); |
ac39cf8c | 3376 | /* |
3377 | * If the page is not charged at this point, | |
3378 | * we return here. | |
3379 | */ | |
3380 | if (!mem) | |
3381 | return 0; | |
01b1ae63 | 3382 | |
93d5c9be | 3383 | *ptr = mem; |
7ec99d62 | 3384 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, 1, ptr, false); |
ac39cf8c | 3385 | css_put(&mem->css);/* drop extra refcnt */ |
3386 | if (ret || *ptr == NULL) { | |
3387 | if (PageAnon(page)) { | |
3388 | lock_page_cgroup(pc); | |
3389 | ClearPageCgroupMigration(pc); | |
3390 | unlock_page_cgroup(pc); | |
3391 | /* | |
3392 | * The old page may be fully unmapped while we kept it. | |
3393 | */ | |
3394 | mem_cgroup_uncharge_page(page); | |
3395 | } | |
3396 | return -ENOMEM; | |
e8589cc1 | 3397 | } |
ac39cf8c | 3398 | /* |
3399 | * We charge new page before it's used/mapped. So, even if unlock_page() | |
3400 | * is called before end_migration, we can catch all events on this new | |
3401 | * page. In the case new page is migrated but not remapped, new page's | |
3402 | * mapcount will be finally 0 and we call uncharge in end_migration(). | |
3403 | */ | |
3404 | pc = lookup_page_cgroup(newpage); | |
3405 | if (PageAnon(page)) | |
3406 | ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED; | |
3407 | else if (page_is_file_cache(page)) | |
3408 | ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; | |
3409 | else | |
3410 | ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; | |
7ec99d62 | 3411 | __mem_cgroup_commit_charge(mem, page, 1, pc, ctype); |
e8589cc1 | 3412 | return ret; |
ae41be37 | 3413 | } |
8869b8f6 | 3414 | |
69029cd5 | 3415 | /* remove redundant charge if migration failed*/ |
01b1ae63 | 3416 | void mem_cgroup_end_migration(struct mem_cgroup *mem, |
50de1dd9 | 3417 | struct page *oldpage, struct page *newpage, bool migration_ok) |
ae41be37 | 3418 | { |
ac39cf8c | 3419 | struct page *used, *unused; |
01b1ae63 | 3420 | struct page_cgroup *pc; |
01b1ae63 KH |
3421 | |
3422 | if (!mem) | |
3423 | return; | |
ac39cf8c | 3424 | /* blocks rmdir() */ |
88703267 | 3425 | cgroup_exclude_rmdir(&mem->css); |
50de1dd9 | 3426 | if (!migration_ok) { |
ac39cf8c | 3427 | used = oldpage; |
3428 | unused = newpage; | |
01b1ae63 | 3429 | } else { |
ac39cf8c | 3430 | used = newpage; |
01b1ae63 KH |
3431 | unused = oldpage; |
3432 | } | |
69029cd5 | 3433 | /* |
ac39cf8c | 3434 | * We disallowed uncharge of pages under migration because mapcount |
3435 | * of the page goes down to zero, temporarly. | |
3436 | * Clear the flag and check the page should be charged. | |
01b1ae63 | 3437 | */ |
ac39cf8c | 3438 | pc = lookup_page_cgroup(oldpage); |
3439 | lock_page_cgroup(pc); | |
3440 | ClearPageCgroupMigration(pc); | |
3441 | unlock_page_cgroup(pc); | |
01b1ae63 | 3442 | |
ac39cf8c | 3443 | __mem_cgroup_uncharge_common(unused, MEM_CGROUP_CHARGE_TYPE_FORCE); |
3444 | ||
01b1ae63 | 3445 | /* |
ac39cf8c | 3446 | * If a page is a file cache, radix-tree replacement is very atomic |
3447 | * and we can skip this check. When it was an Anon page, its mapcount | |
3448 | * goes down to 0. But because we added MIGRATION flage, it's not | |
3449 | * uncharged yet. There are several case but page->mapcount check | |
3450 | * and USED bit check in mem_cgroup_uncharge_page() will do enough | |
3451 | * check. (see prepare_charge() also) | |
69029cd5 | 3452 | */ |
ac39cf8c | 3453 | if (PageAnon(used)) |
3454 | mem_cgroup_uncharge_page(used); | |
88703267 | 3455 | /* |
ac39cf8c | 3456 | * At migration, we may charge account against cgroup which has no |
3457 | * tasks. | |
88703267 KH |
3458 | * So, rmdir()->pre_destroy() can be called while we do this charge. |
3459 | * In that case, we need to call pre_destroy() again. check it here. | |
3460 | */ | |
3461 | cgroup_release_and_wakeup_rmdir(&mem->css); | |
ae41be37 | 3462 | } |
78fb7466 | 3463 | |
f212ad7c DN |
3464 | #ifdef CONFIG_DEBUG_VM |
3465 | static struct page_cgroup *lookup_page_cgroup_used(struct page *page) | |
3466 | { | |
3467 | struct page_cgroup *pc; | |
3468 | ||
3469 | pc = lookup_page_cgroup(page); | |
3470 | if (likely(pc) && PageCgroupUsed(pc)) | |
3471 | return pc; | |
3472 | return NULL; | |
3473 | } | |
3474 | ||
3475 | bool mem_cgroup_bad_page_check(struct page *page) | |
3476 | { | |
3477 | if (mem_cgroup_disabled()) | |
3478 | return false; | |
3479 | ||
3480 | return lookup_page_cgroup_used(page) != NULL; | |
3481 | } | |
3482 | ||
3483 | void mem_cgroup_print_bad_page(struct page *page) | |
3484 | { | |
3485 | struct page_cgroup *pc; | |
3486 | ||
3487 | pc = lookup_page_cgroup_used(page); | |
3488 | if (pc) { | |
3489 | int ret = -1; | |
3490 | char *path; | |
3491 | ||
3492 | printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p", | |
3493 | pc, pc->flags, pc->mem_cgroup); | |
3494 | ||
3495 | path = kmalloc(PATH_MAX, GFP_KERNEL); | |
3496 | if (path) { | |
3497 | rcu_read_lock(); | |
3498 | ret = cgroup_path(pc->mem_cgroup->css.cgroup, | |
3499 | path, PATH_MAX); | |
3500 | rcu_read_unlock(); | |
3501 | } | |
3502 | ||
3503 | printk(KERN_CONT "(%s)\n", | |
3504 | (ret < 0) ? "cannot get the path" : path); | |
3505 | kfree(path); | |
3506 | } | |
3507 | } | |
3508 | #endif | |
3509 | ||
8c7c6e34 KH |
3510 | static DEFINE_MUTEX(set_limit_mutex); |
3511 | ||
d38d2a75 | 3512 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
8c7c6e34 | 3513 | unsigned long long val) |
628f4235 | 3514 | { |
81d39c20 | 3515 | int retry_count; |
3c11ecf4 | 3516 | u64 memswlimit, memlimit; |
628f4235 | 3517 | int ret = 0; |
81d39c20 KH |
3518 | int children = mem_cgroup_count_children(memcg); |
3519 | u64 curusage, oldusage; | |
3c11ecf4 | 3520 | int enlarge; |
81d39c20 KH |
3521 | |
3522 | /* | |
3523 | * For keeping hierarchical_reclaim simple, how long we should retry | |
3524 | * is depends on callers. We set our retry-count to be function | |
3525 | * of # of children which we should visit in this loop. | |
3526 | */ | |
3527 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; | |
3528 | ||
3529 | oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); | |
628f4235 | 3530 | |
3c11ecf4 | 3531 | enlarge = 0; |
8c7c6e34 | 3532 | while (retry_count) { |
628f4235 KH |
3533 | if (signal_pending(current)) { |
3534 | ret = -EINTR; | |
3535 | break; | |
3536 | } | |
8c7c6e34 KH |
3537 | /* |
3538 | * Rather than hide all in some function, I do this in | |
3539 | * open coded manner. You see what this really does. | |
3540 | * We have to guarantee mem->res.limit < mem->memsw.limit. | |
3541 | */ | |
3542 | mutex_lock(&set_limit_mutex); | |
3543 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
3544 | if (memswlimit < val) { | |
3545 | ret = -EINVAL; | |
3546 | mutex_unlock(&set_limit_mutex); | |
628f4235 KH |
3547 | break; |
3548 | } | |
3c11ecf4 KH |
3549 | |
3550 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3551 | if (memlimit < val) | |
3552 | enlarge = 1; | |
3553 | ||
8c7c6e34 | 3554 | ret = res_counter_set_limit(&memcg->res, val); |
22a668d7 KH |
3555 | if (!ret) { |
3556 | if (memswlimit == val) | |
3557 | memcg->memsw_is_minimum = true; | |
3558 | else | |
3559 | memcg->memsw_is_minimum = false; | |
3560 | } | |
8c7c6e34 KH |
3561 | mutex_unlock(&set_limit_mutex); |
3562 | ||
3563 | if (!ret) | |
3564 | break; | |
3565 | ||
aa20d489 | 3566 | mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, |
0ae5e89c YH |
3567 | MEM_CGROUP_RECLAIM_SHRINK, |
3568 | NULL); | |
81d39c20 KH |
3569 | curusage = res_counter_read_u64(&memcg->res, RES_USAGE); |
3570 | /* Usage is reduced ? */ | |
3571 | if (curusage >= oldusage) | |
3572 | retry_count--; | |
3573 | else | |
3574 | oldusage = curusage; | |
8c7c6e34 | 3575 | } |
3c11ecf4 KH |
3576 | if (!ret && enlarge) |
3577 | memcg_oom_recover(memcg); | |
14797e23 | 3578 | |
8c7c6e34 KH |
3579 | return ret; |
3580 | } | |
3581 | ||
338c8431 LZ |
3582 | static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, |
3583 | unsigned long long val) | |
8c7c6e34 | 3584 | { |
81d39c20 | 3585 | int retry_count; |
3c11ecf4 | 3586 | u64 memlimit, memswlimit, oldusage, curusage; |
81d39c20 KH |
3587 | int children = mem_cgroup_count_children(memcg); |
3588 | int ret = -EBUSY; | |
3c11ecf4 | 3589 | int enlarge = 0; |
8c7c6e34 | 3590 | |
81d39c20 KH |
3591 | /* see mem_cgroup_resize_res_limit */ |
3592 | retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; | |
3593 | oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); | |
8c7c6e34 KH |
3594 | while (retry_count) { |
3595 | if (signal_pending(current)) { | |
3596 | ret = -EINTR; | |
3597 | break; | |
3598 | } | |
3599 | /* | |
3600 | * Rather than hide all in some function, I do this in | |
3601 | * open coded manner. You see what this really does. | |
3602 | * We have to guarantee mem->res.limit < mem->memsw.limit. | |
3603 | */ | |
3604 | mutex_lock(&set_limit_mutex); | |
3605 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3606 | if (memlimit > val) { | |
3607 | ret = -EINVAL; | |
3608 | mutex_unlock(&set_limit_mutex); | |
3609 | break; | |
3610 | } | |
3c11ecf4 KH |
3611 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
3612 | if (memswlimit < val) | |
3613 | enlarge = 1; | |
8c7c6e34 | 3614 | ret = res_counter_set_limit(&memcg->memsw, val); |
22a668d7 KH |
3615 | if (!ret) { |
3616 | if (memlimit == val) | |
3617 | memcg->memsw_is_minimum = true; | |
3618 | else | |
3619 | memcg->memsw_is_minimum = false; | |
3620 | } | |
8c7c6e34 KH |
3621 | mutex_unlock(&set_limit_mutex); |
3622 | ||
3623 | if (!ret) | |
3624 | break; | |
3625 | ||
4e416953 | 3626 | mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, |
75822b44 | 3627 | MEM_CGROUP_RECLAIM_NOSWAP | |
0ae5e89c YH |
3628 | MEM_CGROUP_RECLAIM_SHRINK, |
3629 | NULL); | |
8c7c6e34 | 3630 | curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); |
81d39c20 | 3631 | /* Usage is reduced ? */ |
8c7c6e34 | 3632 | if (curusage >= oldusage) |
628f4235 | 3633 | retry_count--; |
81d39c20 KH |
3634 | else |
3635 | oldusage = curusage; | |
628f4235 | 3636 | } |
3c11ecf4 KH |
3637 | if (!ret && enlarge) |
3638 | memcg_oom_recover(memcg); | |
628f4235 KH |
3639 | return ret; |
3640 | } | |
3641 | ||
4e416953 | 3642 | unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, |
0ae5e89c YH |
3643 | gfp_t gfp_mask, |
3644 | unsigned long *total_scanned) | |
4e416953 BS |
3645 | { |
3646 | unsigned long nr_reclaimed = 0; | |
3647 | struct mem_cgroup_per_zone *mz, *next_mz = NULL; | |
3648 | unsigned long reclaimed; | |
3649 | int loop = 0; | |
3650 | struct mem_cgroup_tree_per_zone *mctz; | |
ef8745c1 | 3651 | unsigned long long excess; |
0ae5e89c | 3652 | unsigned long nr_scanned; |
4e416953 BS |
3653 | |
3654 | if (order > 0) | |
3655 | return 0; | |
3656 | ||
00918b6a | 3657 | mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone)); |
4e416953 BS |
3658 | /* |
3659 | * This loop can run a while, specially if mem_cgroup's continuously | |
3660 | * keep exceeding their soft limit and putting the system under | |
3661 | * pressure | |
3662 | */ | |
3663 | do { | |
3664 | if (next_mz) | |
3665 | mz = next_mz; | |
3666 | else | |
3667 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
3668 | if (!mz) | |
3669 | break; | |
3670 | ||
0ae5e89c | 3671 | nr_scanned = 0; |
4e416953 BS |
3672 | reclaimed = mem_cgroup_hierarchical_reclaim(mz->mem, zone, |
3673 | gfp_mask, | |
0ae5e89c YH |
3674 | MEM_CGROUP_RECLAIM_SOFT, |
3675 | &nr_scanned); | |
4e416953 | 3676 | nr_reclaimed += reclaimed; |
0ae5e89c | 3677 | *total_scanned += nr_scanned; |
4e416953 BS |
3678 | spin_lock(&mctz->lock); |
3679 | ||
3680 | /* | |
3681 | * If we failed to reclaim anything from this memory cgroup | |
3682 | * it is time to move on to the next cgroup | |
3683 | */ | |
3684 | next_mz = NULL; | |
3685 | if (!reclaimed) { | |
3686 | do { | |
3687 | /* | |
3688 | * Loop until we find yet another one. | |
3689 | * | |
3690 | * By the time we get the soft_limit lock | |
3691 | * again, someone might have aded the | |
3692 | * group back on the RB tree. Iterate to | |
3693 | * make sure we get a different mem. | |
3694 | * mem_cgroup_largest_soft_limit_node returns | |
3695 | * NULL if no other cgroup is present on | |
3696 | * the tree | |
3697 | */ | |
3698 | next_mz = | |
3699 | __mem_cgroup_largest_soft_limit_node(mctz); | |
39cc98f1 | 3700 | if (next_mz == mz) |
4e416953 | 3701 | css_put(&next_mz->mem->css); |
39cc98f1 | 3702 | else /* next_mz == NULL or other memcg */ |
4e416953 BS |
3703 | break; |
3704 | } while (1); | |
3705 | } | |
4e416953 | 3706 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); |
ef8745c1 | 3707 | excess = res_counter_soft_limit_excess(&mz->mem->res); |
4e416953 BS |
3708 | /* |
3709 | * One school of thought says that we should not add | |
3710 | * back the node to the tree if reclaim returns 0. | |
3711 | * But our reclaim could return 0, simply because due | |
3712 | * to priority we are exposing a smaller subset of | |
3713 | * memory to reclaim from. Consider this as a longer | |
3714 | * term TODO. | |
3715 | */ | |
ef8745c1 KH |
3716 | /* If excess == 0, no tree ops */ |
3717 | __mem_cgroup_insert_exceeded(mz->mem, mz, mctz, excess); | |
4e416953 BS |
3718 | spin_unlock(&mctz->lock); |
3719 | css_put(&mz->mem->css); | |
3720 | loop++; | |
3721 | /* | |
3722 | * Could not reclaim anything and there are no more | |
3723 | * mem cgroups to try or we seem to be looping without | |
3724 | * reclaiming anything. | |
3725 | */ | |
3726 | if (!nr_reclaimed && | |
3727 | (next_mz == NULL || | |
3728 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
3729 | break; | |
3730 | } while (!nr_reclaimed); | |
3731 | if (next_mz) | |
3732 | css_put(&next_mz->mem->css); | |
3733 | return nr_reclaimed; | |
3734 | } | |
3735 | ||
cc847582 KH |
3736 | /* |
3737 | * This routine traverse page_cgroup in given list and drop them all. | |
cc847582 KH |
3738 | * *And* this routine doesn't reclaim page itself, just removes page_cgroup. |
3739 | */ | |
f817ed48 | 3740 | static int mem_cgroup_force_empty_list(struct mem_cgroup *mem, |
08e552c6 | 3741 | int node, int zid, enum lru_list lru) |
cc847582 | 3742 | { |
08e552c6 KH |
3743 | struct zone *zone; |
3744 | struct mem_cgroup_per_zone *mz; | |
f817ed48 | 3745 | struct page_cgroup *pc, *busy; |
08e552c6 | 3746 | unsigned long flags, loop; |
072c56c1 | 3747 | struct list_head *list; |
f817ed48 | 3748 | int ret = 0; |
072c56c1 | 3749 | |
08e552c6 KH |
3750 | zone = &NODE_DATA(node)->node_zones[zid]; |
3751 | mz = mem_cgroup_zoneinfo(mem, node, zid); | |
b69408e8 | 3752 | list = &mz->lists[lru]; |
cc847582 | 3753 | |
f817ed48 KH |
3754 | loop = MEM_CGROUP_ZSTAT(mz, lru); |
3755 | /* give some margin against EBUSY etc...*/ | |
3756 | loop += 256; | |
3757 | busy = NULL; | |
3758 | while (loop--) { | |
5564e88b JW |
3759 | struct page *page; |
3760 | ||
f817ed48 | 3761 | ret = 0; |
08e552c6 | 3762 | spin_lock_irqsave(&zone->lru_lock, flags); |
f817ed48 | 3763 | if (list_empty(list)) { |
08e552c6 | 3764 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
52d4b9ac | 3765 | break; |
f817ed48 KH |
3766 | } |
3767 | pc = list_entry(list->prev, struct page_cgroup, lru); | |
3768 | if (busy == pc) { | |
3769 | list_move(&pc->lru, list); | |
648bcc77 | 3770 | busy = NULL; |
08e552c6 | 3771 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 KH |
3772 | continue; |
3773 | } | |
08e552c6 | 3774 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 | 3775 | |
6b3ae58e | 3776 | page = lookup_cgroup_page(pc); |
5564e88b JW |
3777 | |
3778 | ret = mem_cgroup_move_parent(page, pc, mem, GFP_KERNEL); | |
f817ed48 | 3779 | if (ret == -ENOMEM) |
52d4b9ac | 3780 | break; |
f817ed48 KH |
3781 | |
3782 | if (ret == -EBUSY || ret == -EINVAL) { | |
3783 | /* found lock contention or "pc" is obsolete. */ | |
3784 | busy = pc; | |
3785 | cond_resched(); | |
3786 | } else | |
3787 | busy = NULL; | |
cc847582 | 3788 | } |
08e552c6 | 3789 | |
f817ed48 KH |
3790 | if (!ret && !list_empty(list)) |
3791 | return -EBUSY; | |
3792 | return ret; | |
cc847582 KH |
3793 | } |
3794 | ||
3795 | /* | |
3796 | * make mem_cgroup's charge to be 0 if there is no task. | |
3797 | * This enables deleting this mem_cgroup. | |
3798 | */ | |
c1e862c1 | 3799 | static int mem_cgroup_force_empty(struct mem_cgroup *mem, bool free_all) |
cc847582 | 3800 | { |
f817ed48 KH |
3801 | int ret; |
3802 | int node, zid, shrink; | |
3803 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
c1e862c1 | 3804 | struct cgroup *cgrp = mem->css.cgroup; |
8869b8f6 | 3805 | |
cc847582 | 3806 | css_get(&mem->css); |
f817ed48 KH |
3807 | |
3808 | shrink = 0; | |
c1e862c1 KH |
3809 | /* should free all ? */ |
3810 | if (free_all) | |
3811 | goto try_to_free; | |
f817ed48 | 3812 | move_account: |
fce66477 | 3813 | do { |
f817ed48 | 3814 | ret = -EBUSY; |
c1e862c1 KH |
3815 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children)) |
3816 | goto out; | |
3817 | ret = -EINTR; | |
3818 | if (signal_pending(current)) | |
cc847582 | 3819 | goto out; |
52d4b9ac KH |
3820 | /* This is for making all *used* pages to be on LRU. */ |
3821 | lru_add_drain_all(); | |
d38144b7 | 3822 | drain_all_stock_sync(mem); |
f817ed48 | 3823 | ret = 0; |
32047e2a | 3824 | mem_cgroup_start_move(mem); |
299b4eaa | 3825 | for_each_node_state(node, N_HIGH_MEMORY) { |
f817ed48 | 3826 | for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { |
b69408e8 | 3827 | enum lru_list l; |
f817ed48 KH |
3828 | for_each_lru(l) { |
3829 | ret = mem_cgroup_force_empty_list(mem, | |
08e552c6 | 3830 | node, zid, l); |
f817ed48 KH |
3831 | if (ret) |
3832 | break; | |
3833 | } | |
1ecaab2b | 3834 | } |
f817ed48 KH |
3835 | if (ret) |
3836 | break; | |
3837 | } | |
32047e2a | 3838 | mem_cgroup_end_move(mem); |
3c11ecf4 | 3839 | memcg_oom_recover(mem); |
f817ed48 KH |
3840 | /* it seems parent cgroup doesn't have enough mem */ |
3841 | if (ret == -ENOMEM) | |
3842 | goto try_to_free; | |
52d4b9ac | 3843 | cond_resched(); |
fce66477 DN |
3844 | /* "ret" should also be checked to ensure all lists are empty. */ |
3845 | } while (mem->res.usage > 0 || ret); | |
cc847582 KH |
3846 | out: |
3847 | css_put(&mem->css); | |
3848 | return ret; | |
f817ed48 KH |
3849 | |
3850 | try_to_free: | |
c1e862c1 KH |
3851 | /* returns EBUSY if there is a task or if we come here twice. */ |
3852 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) { | |
f817ed48 KH |
3853 | ret = -EBUSY; |
3854 | goto out; | |
3855 | } | |
c1e862c1 KH |
3856 | /* we call try-to-free pages for make this cgroup empty */ |
3857 | lru_add_drain_all(); | |
f817ed48 KH |
3858 | /* try to free all pages in this cgroup */ |
3859 | shrink = 1; | |
3860 | while (nr_retries && mem->res.usage > 0) { | |
82f9d486 | 3861 | struct memcg_scanrecord rec; |
f817ed48 | 3862 | int progress; |
c1e862c1 KH |
3863 | |
3864 | if (signal_pending(current)) { | |
3865 | ret = -EINTR; | |
3866 | goto out; | |
3867 | } | |
82f9d486 KH |
3868 | rec.context = SCAN_BY_SHRINK; |
3869 | rec.mem = mem; | |
3870 | rec.root = mem; | |
a7885eb8 | 3871 | progress = try_to_free_mem_cgroup_pages(mem, GFP_KERNEL, |
82f9d486 | 3872 | false, &rec); |
c1e862c1 | 3873 | if (!progress) { |
f817ed48 | 3874 | nr_retries--; |
c1e862c1 | 3875 | /* maybe some writeback is necessary */ |
8aa7e847 | 3876 | congestion_wait(BLK_RW_ASYNC, HZ/10); |
c1e862c1 | 3877 | } |
f817ed48 KH |
3878 | |
3879 | } | |
08e552c6 | 3880 | lru_add_drain(); |
f817ed48 | 3881 | /* try move_account...there may be some *locked* pages. */ |
fce66477 | 3882 | goto move_account; |
cc847582 KH |
3883 | } |
3884 | ||
c1e862c1 KH |
3885 | int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event) |
3886 | { | |
3887 | return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true); | |
3888 | } | |
3889 | ||
3890 | ||
18f59ea7 BS |
3891 | static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft) |
3892 | { | |
3893 | return mem_cgroup_from_cont(cont)->use_hierarchy; | |
3894 | } | |
3895 | ||
3896 | static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft, | |
3897 | u64 val) | |
3898 | { | |
3899 | int retval = 0; | |
3900 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); | |
3901 | struct cgroup *parent = cont->parent; | |
3902 | struct mem_cgroup *parent_mem = NULL; | |
3903 | ||
3904 | if (parent) | |
3905 | parent_mem = mem_cgroup_from_cont(parent); | |
3906 | ||
3907 | cgroup_lock(); | |
3908 | /* | |
af901ca1 | 3909 | * If parent's use_hierarchy is set, we can't make any modifications |
18f59ea7 BS |
3910 | * in the child subtrees. If it is unset, then the change can |
3911 | * occur, provided the current cgroup has no children. | |
3912 | * | |
3913 | * For the root cgroup, parent_mem is NULL, we allow value to be | |
3914 | * set if there are no children. | |
3915 | */ | |
3916 | if ((!parent_mem || !parent_mem->use_hierarchy) && | |
3917 | (val == 1 || val == 0)) { | |
3918 | if (list_empty(&cont->children)) | |
3919 | mem->use_hierarchy = val; | |
3920 | else | |
3921 | retval = -EBUSY; | |
3922 | } else | |
3923 | retval = -EINVAL; | |
3924 | cgroup_unlock(); | |
3925 | ||
3926 | return retval; | |
3927 | } | |
3928 | ||
0c3e73e8 | 3929 | |
7a159cc9 JW |
3930 | static unsigned long mem_cgroup_recursive_stat(struct mem_cgroup *mem, |
3931 | enum mem_cgroup_stat_index idx) | |
0c3e73e8 | 3932 | { |
7d74b06f | 3933 | struct mem_cgroup *iter; |
7a159cc9 | 3934 | long val = 0; |
0c3e73e8 | 3935 | |
7a159cc9 | 3936 | /* Per-cpu values can be negative, use a signed accumulator */ |
7d74b06f KH |
3937 | for_each_mem_cgroup_tree(iter, mem) |
3938 | val += mem_cgroup_read_stat(iter, idx); | |
3939 | ||
3940 | if (val < 0) /* race ? */ | |
3941 | val = 0; | |
3942 | return val; | |
0c3e73e8 BS |
3943 | } |
3944 | ||
104f3928 KS |
3945 | static inline u64 mem_cgroup_usage(struct mem_cgroup *mem, bool swap) |
3946 | { | |
7d74b06f | 3947 | u64 val; |
104f3928 KS |
3948 | |
3949 | if (!mem_cgroup_is_root(mem)) { | |
3950 | if (!swap) | |
3951 | return res_counter_read_u64(&mem->res, RES_USAGE); | |
3952 | else | |
3953 | return res_counter_read_u64(&mem->memsw, RES_USAGE); | |
3954 | } | |
3955 | ||
7a159cc9 JW |
3956 | val = mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_CACHE); |
3957 | val += mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_RSS); | |
104f3928 | 3958 | |
7d74b06f | 3959 | if (swap) |
7a159cc9 | 3960 | val += mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_SWAPOUT); |
104f3928 KS |
3961 | |
3962 | return val << PAGE_SHIFT; | |
3963 | } | |
3964 | ||
2c3daa72 | 3965 | static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) |
8cdea7c0 | 3966 | { |
8c7c6e34 | 3967 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
104f3928 | 3968 | u64 val; |
8c7c6e34 KH |
3969 | int type, name; |
3970 | ||
3971 | type = MEMFILE_TYPE(cft->private); | |
3972 | name = MEMFILE_ATTR(cft->private); | |
3973 | switch (type) { | |
3974 | case _MEM: | |
104f3928 KS |
3975 | if (name == RES_USAGE) |
3976 | val = mem_cgroup_usage(mem, false); | |
3977 | else | |
0c3e73e8 | 3978 | val = res_counter_read_u64(&mem->res, name); |
8c7c6e34 KH |
3979 | break; |
3980 | case _MEMSWAP: | |
104f3928 KS |
3981 | if (name == RES_USAGE) |
3982 | val = mem_cgroup_usage(mem, true); | |
3983 | else | |
0c3e73e8 | 3984 | val = res_counter_read_u64(&mem->memsw, name); |
8c7c6e34 KH |
3985 | break; |
3986 | default: | |
3987 | BUG(); | |
3988 | break; | |
3989 | } | |
3990 | return val; | |
8cdea7c0 | 3991 | } |
628f4235 KH |
3992 | /* |
3993 | * The user of this function is... | |
3994 | * RES_LIMIT. | |
3995 | */ | |
856c13aa PM |
3996 | static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, |
3997 | const char *buffer) | |
8cdea7c0 | 3998 | { |
628f4235 | 3999 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
8c7c6e34 | 4000 | int type, name; |
628f4235 KH |
4001 | unsigned long long val; |
4002 | int ret; | |
4003 | ||
8c7c6e34 KH |
4004 | type = MEMFILE_TYPE(cft->private); |
4005 | name = MEMFILE_ATTR(cft->private); | |
4006 | switch (name) { | |
628f4235 | 4007 | case RES_LIMIT: |
4b3bde4c BS |
4008 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
4009 | ret = -EINVAL; | |
4010 | break; | |
4011 | } | |
628f4235 KH |
4012 | /* This function does all necessary parse...reuse it */ |
4013 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
8c7c6e34 KH |
4014 | if (ret) |
4015 | break; | |
4016 | if (type == _MEM) | |
628f4235 | 4017 | ret = mem_cgroup_resize_limit(memcg, val); |
8c7c6e34 KH |
4018 | else |
4019 | ret = mem_cgroup_resize_memsw_limit(memcg, val); | |
628f4235 | 4020 | break; |
296c81d8 BS |
4021 | case RES_SOFT_LIMIT: |
4022 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
4023 | if (ret) | |
4024 | break; | |
4025 | /* | |
4026 | * For memsw, soft limits are hard to implement in terms | |
4027 | * of semantics, for now, we support soft limits for | |
4028 | * control without swap | |
4029 | */ | |
4030 | if (type == _MEM) | |
4031 | ret = res_counter_set_soft_limit(&memcg->res, val); | |
4032 | else | |
4033 | ret = -EINVAL; | |
4034 | break; | |
628f4235 KH |
4035 | default: |
4036 | ret = -EINVAL; /* should be BUG() ? */ | |
4037 | break; | |
4038 | } | |
4039 | return ret; | |
8cdea7c0 BS |
4040 | } |
4041 | ||
fee7b548 KH |
4042 | static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, |
4043 | unsigned long long *mem_limit, unsigned long long *memsw_limit) | |
4044 | { | |
4045 | struct cgroup *cgroup; | |
4046 | unsigned long long min_limit, min_memsw_limit, tmp; | |
4047 | ||
4048 | min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
4049 | min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
4050 | cgroup = memcg->css.cgroup; | |
4051 | if (!memcg->use_hierarchy) | |
4052 | goto out; | |
4053 | ||
4054 | while (cgroup->parent) { | |
4055 | cgroup = cgroup->parent; | |
4056 | memcg = mem_cgroup_from_cont(cgroup); | |
4057 | if (!memcg->use_hierarchy) | |
4058 | break; | |
4059 | tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
4060 | min_limit = min(min_limit, tmp); | |
4061 | tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
4062 | min_memsw_limit = min(min_memsw_limit, tmp); | |
4063 | } | |
4064 | out: | |
4065 | *mem_limit = min_limit; | |
4066 | *memsw_limit = min_memsw_limit; | |
4067 | return; | |
4068 | } | |
4069 | ||
29f2a4da | 4070 | static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) |
c84872e1 PE |
4071 | { |
4072 | struct mem_cgroup *mem; | |
8c7c6e34 | 4073 | int type, name; |
c84872e1 PE |
4074 | |
4075 | mem = mem_cgroup_from_cont(cont); | |
8c7c6e34 KH |
4076 | type = MEMFILE_TYPE(event); |
4077 | name = MEMFILE_ATTR(event); | |
4078 | switch (name) { | |
29f2a4da | 4079 | case RES_MAX_USAGE: |
8c7c6e34 KH |
4080 | if (type == _MEM) |
4081 | res_counter_reset_max(&mem->res); | |
4082 | else | |
4083 | res_counter_reset_max(&mem->memsw); | |
29f2a4da PE |
4084 | break; |
4085 | case RES_FAILCNT: | |
8c7c6e34 KH |
4086 | if (type == _MEM) |
4087 | res_counter_reset_failcnt(&mem->res); | |
4088 | else | |
4089 | res_counter_reset_failcnt(&mem->memsw); | |
29f2a4da PE |
4090 | break; |
4091 | } | |
f64c3f54 | 4092 | |
85cc59db | 4093 | return 0; |
c84872e1 PE |
4094 | } |
4095 | ||
7dc74be0 DN |
4096 | static u64 mem_cgroup_move_charge_read(struct cgroup *cgrp, |
4097 | struct cftype *cft) | |
4098 | { | |
4099 | return mem_cgroup_from_cont(cgrp)->move_charge_at_immigrate; | |
4100 | } | |
4101 | ||
02491447 | 4102 | #ifdef CONFIG_MMU |
7dc74be0 DN |
4103 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, |
4104 | struct cftype *cft, u64 val) | |
4105 | { | |
4106 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4107 | ||
4108 | if (val >= (1 << NR_MOVE_TYPE)) | |
4109 | return -EINVAL; | |
4110 | /* | |
4111 | * We check this value several times in both in can_attach() and | |
4112 | * attach(), so we need cgroup lock to prevent this value from being | |
4113 | * inconsistent. | |
4114 | */ | |
4115 | cgroup_lock(); | |
4116 | mem->move_charge_at_immigrate = val; | |
4117 | cgroup_unlock(); | |
4118 | ||
4119 | return 0; | |
4120 | } | |
02491447 DN |
4121 | #else |
4122 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, | |
4123 | struct cftype *cft, u64 val) | |
4124 | { | |
4125 | return -ENOSYS; | |
4126 | } | |
4127 | #endif | |
7dc74be0 | 4128 | |
14067bb3 KH |
4129 | |
4130 | /* For read statistics */ | |
4131 | enum { | |
4132 | MCS_CACHE, | |
4133 | MCS_RSS, | |
d8046582 | 4134 | MCS_FILE_MAPPED, |
14067bb3 KH |
4135 | MCS_PGPGIN, |
4136 | MCS_PGPGOUT, | |
1dd3a273 | 4137 | MCS_SWAP, |
456f998e YH |
4138 | MCS_PGFAULT, |
4139 | MCS_PGMAJFAULT, | |
14067bb3 KH |
4140 | MCS_INACTIVE_ANON, |
4141 | MCS_ACTIVE_ANON, | |
4142 | MCS_INACTIVE_FILE, | |
4143 | MCS_ACTIVE_FILE, | |
4144 | MCS_UNEVICTABLE, | |
4145 | NR_MCS_STAT, | |
4146 | }; | |
4147 | ||
4148 | struct mcs_total_stat { | |
4149 | s64 stat[NR_MCS_STAT]; | |
d2ceb9b7 KH |
4150 | }; |
4151 | ||
14067bb3 KH |
4152 | struct { |
4153 | char *local_name; | |
4154 | char *total_name; | |
4155 | } memcg_stat_strings[NR_MCS_STAT] = { | |
4156 | {"cache", "total_cache"}, | |
4157 | {"rss", "total_rss"}, | |
d69b042f | 4158 | {"mapped_file", "total_mapped_file"}, |
14067bb3 KH |
4159 | {"pgpgin", "total_pgpgin"}, |
4160 | {"pgpgout", "total_pgpgout"}, | |
1dd3a273 | 4161 | {"swap", "total_swap"}, |
456f998e YH |
4162 | {"pgfault", "total_pgfault"}, |
4163 | {"pgmajfault", "total_pgmajfault"}, | |
14067bb3 KH |
4164 | {"inactive_anon", "total_inactive_anon"}, |
4165 | {"active_anon", "total_active_anon"}, | |
4166 | {"inactive_file", "total_inactive_file"}, | |
4167 | {"active_file", "total_active_file"}, | |
4168 | {"unevictable", "total_unevictable"} | |
4169 | }; | |
4170 | ||
4171 | ||
7d74b06f KH |
4172 | static void |
4173 | mem_cgroup_get_local_stat(struct mem_cgroup *mem, struct mcs_total_stat *s) | |
14067bb3 | 4174 | { |
14067bb3 KH |
4175 | s64 val; |
4176 | ||
4177 | /* per cpu stat */ | |
c62b1a3b | 4178 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_CACHE); |
14067bb3 | 4179 | s->stat[MCS_CACHE] += val * PAGE_SIZE; |
c62b1a3b | 4180 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_RSS); |
14067bb3 | 4181 | s->stat[MCS_RSS] += val * PAGE_SIZE; |
c62b1a3b | 4182 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_FILE_MAPPED); |
d8046582 | 4183 | s->stat[MCS_FILE_MAPPED] += val * PAGE_SIZE; |
e9f8974f | 4184 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGPGIN); |
14067bb3 | 4185 | s->stat[MCS_PGPGIN] += val; |
e9f8974f | 4186 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGPGOUT); |
14067bb3 | 4187 | s->stat[MCS_PGPGOUT] += val; |
1dd3a273 | 4188 | if (do_swap_account) { |
c62b1a3b | 4189 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_SWAPOUT); |
1dd3a273 DN |
4190 | s->stat[MCS_SWAP] += val * PAGE_SIZE; |
4191 | } | |
456f998e YH |
4192 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGFAULT); |
4193 | s->stat[MCS_PGFAULT] += val; | |
4194 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGMAJFAULT); | |
4195 | s->stat[MCS_PGMAJFAULT] += val; | |
14067bb3 KH |
4196 | |
4197 | /* per zone stat */ | |
bb2a0de9 | 4198 | val = mem_cgroup_nr_lru_pages(mem, BIT(LRU_INACTIVE_ANON)); |
14067bb3 | 4199 | s->stat[MCS_INACTIVE_ANON] += val * PAGE_SIZE; |
bb2a0de9 | 4200 | val = mem_cgroup_nr_lru_pages(mem, BIT(LRU_ACTIVE_ANON)); |
14067bb3 | 4201 | s->stat[MCS_ACTIVE_ANON] += val * PAGE_SIZE; |
bb2a0de9 | 4202 | val = mem_cgroup_nr_lru_pages(mem, BIT(LRU_INACTIVE_FILE)); |
14067bb3 | 4203 | s->stat[MCS_INACTIVE_FILE] += val * PAGE_SIZE; |
bb2a0de9 | 4204 | val = mem_cgroup_nr_lru_pages(mem, BIT(LRU_ACTIVE_FILE)); |
14067bb3 | 4205 | s->stat[MCS_ACTIVE_FILE] += val * PAGE_SIZE; |
bb2a0de9 | 4206 | val = mem_cgroup_nr_lru_pages(mem, BIT(LRU_UNEVICTABLE)); |
14067bb3 | 4207 | s->stat[MCS_UNEVICTABLE] += val * PAGE_SIZE; |
14067bb3 KH |
4208 | } |
4209 | ||
4210 | static void | |
4211 | mem_cgroup_get_total_stat(struct mem_cgroup *mem, struct mcs_total_stat *s) | |
4212 | { | |
7d74b06f KH |
4213 | struct mem_cgroup *iter; |
4214 | ||
4215 | for_each_mem_cgroup_tree(iter, mem) | |
4216 | mem_cgroup_get_local_stat(iter, s); | |
14067bb3 KH |
4217 | } |
4218 | ||
406eb0c9 YH |
4219 | #ifdef CONFIG_NUMA |
4220 | static int mem_control_numa_stat_show(struct seq_file *m, void *arg) | |
4221 | { | |
4222 | int nid; | |
4223 | unsigned long total_nr, file_nr, anon_nr, unevictable_nr; | |
4224 | unsigned long node_nr; | |
4225 | struct cgroup *cont = m->private; | |
4226 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); | |
4227 | ||
bb2a0de9 | 4228 | total_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL); |
406eb0c9 YH |
4229 | seq_printf(m, "total=%lu", total_nr); |
4230 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 | 4231 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, LRU_ALL); |
406eb0c9 YH |
4232 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4233 | } | |
4234 | seq_putc(m, '\n'); | |
4235 | ||
bb2a0de9 | 4236 | file_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL_FILE); |
406eb0c9 YH |
4237 | seq_printf(m, "file=%lu", file_nr); |
4238 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4239 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4240 | LRU_ALL_FILE); | |
406eb0c9 YH |
4241 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4242 | } | |
4243 | seq_putc(m, '\n'); | |
4244 | ||
bb2a0de9 | 4245 | anon_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL_ANON); |
406eb0c9 YH |
4246 | seq_printf(m, "anon=%lu", anon_nr); |
4247 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4248 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4249 | LRU_ALL_ANON); | |
406eb0c9 YH |
4250 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4251 | } | |
4252 | seq_putc(m, '\n'); | |
4253 | ||
bb2a0de9 | 4254 | unevictable_nr = mem_cgroup_nr_lru_pages(mem_cont, BIT(LRU_UNEVICTABLE)); |
406eb0c9 YH |
4255 | seq_printf(m, "unevictable=%lu", unevictable_nr); |
4256 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4257 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4258 | BIT(LRU_UNEVICTABLE)); | |
406eb0c9 YH |
4259 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4260 | } | |
4261 | seq_putc(m, '\n'); | |
4262 | return 0; | |
4263 | } | |
4264 | #endif /* CONFIG_NUMA */ | |
4265 | ||
c64745cf PM |
4266 | static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, |
4267 | struct cgroup_map_cb *cb) | |
d2ceb9b7 | 4268 | { |
d2ceb9b7 | 4269 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); |
14067bb3 | 4270 | struct mcs_total_stat mystat; |
d2ceb9b7 KH |
4271 | int i; |
4272 | ||
14067bb3 KH |
4273 | memset(&mystat, 0, sizeof(mystat)); |
4274 | mem_cgroup_get_local_stat(mem_cont, &mystat); | |
d2ceb9b7 | 4275 | |
406eb0c9 | 4276 | |
1dd3a273 DN |
4277 | for (i = 0; i < NR_MCS_STAT; i++) { |
4278 | if (i == MCS_SWAP && !do_swap_account) | |
4279 | continue; | |
14067bb3 | 4280 | cb->fill(cb, memcg_stat_strings[i].local_name, mystat.stat[i]); |
1dd3a273 | 4281 | } |
7b854121 | 4282 | |
14067bb3 | 4283 | /* Hierarchical information */ |
fee7b548 KH |
4284 | { |
4285 | unsigned long long limit, memsw_limit; | |
4286 | memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit); | |
4287 | cb->fill(cb, "hierarchical_memory_limit", limit); | |
4288 | if (do_swap_account) | |
4289 | cb->fill(cb, "hierarchical_memsw_limit", memsw_limit); | |
4290 | } | |
7f016ee8 | 4291 | |
14067bb3 KH |
4292 | memset(&mystat, 0, sizeof(mystat)); |
4293 | mem_cgroup_get_total_stat(mem_cont, &mystat); | |
1dd3a273 DN |
4294 | for (i = 0; i < NR_MCS_STAT; i++) { |
4295 | if (i == MCS_SWAP && !do_swap_account) | |
4296 | continue; | |
14067bb3 | 4297 | cb->fill(cb, memcg_stat_strings[i].total_name, mystat.stat[i]); |
1dd3a273 | 4298 | } |
14067bb3 | 4299 | |
7f016ee8 | 4300 | #ifdef CONFIG_DEBUG_VM |
c772be93 | 4301 | cb->fill(cb, "inactive_ratio", calc_inactive_ratio(mem_cont, NULL)); |
7f016ee8 KM |
4302 | |
4303 | { | |
4304 | int nid, zid; | |
4305 | struct mem_cgroup_per_zone *mz; | |
4306 | unsigned long recent_rotated[2] = {0, 0}; | |
4307 | unsigned long recent_scanned[2] = {0, 0}; | |
4308 | ||
4309 | for_each_online_node(nid) | |
4310 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
4311 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); | |
4312 | ||
4313 | recent_rotated[0] += | |
4314 | mz->reclaim_stat.recent_rotated[0]; | |
4315 | recent_rotated[1] += | |
4316 | mz->reclaim_stat.recent_rotated[1]; | |
4317 | recent_scanned[0] += | |
4318 | mz->reclaim_stat.recent_scanned[0]; | |
4319 | recent_scanned[1] += | |
4320 | mz->reclaim_stat.recent_scanned[1]; | |
4321 | } | |
4322 | cb->fill(cb, "recent_rotated_anon", recent_rotated[0]); | |
4323 | cb->fill(cb, "recent_rotated_file", recent_rotated[1]); | |
4324 | cb->fill(cb, "recent_scanned_anon", recent_scanned[0]); | |
4325 | cb->fill(cb, "recent_scanned_file", recent_scanned[1]); | |
4326 | } | |
4327 | #endif | |
4328 | ||
d2ceb9b7 KH |
4329 | return 0; |
4330 | } | |
4331 | ||
a7885eb8 KM |
4332 | static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft) |
4333 | { | |
4334 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4335 | ||
1f4c025b | 4336 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
4337 | } |
4338 | ||
4339 | static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, | |
4340 | u64 val) | |
4341 | { | |
4342 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4343 | struct mem_cgroup *parent; | |
068b38c1 | 4344 | |
a7885eb8 KM |
4345 | if (val > 100) |
4346 | return -EINVAL; | |
4347 | ||
4348 | if (cgrp->parent == NULL) | |
4349 | return -EINVAL; | |
4350 | ||
4351 | parent = mem_cgroup_from_cont(cgrp->parent); | |
068b38c1 LZ |
4352 | |
4353 | cgroup_lock(); | |
4354 | ||
a7885eb8 KM |
4355 | /* If under hierarchy, only empty-root can set this value */ |
4356 | if ((parent->use_hierarchy) || | |
068b38c1 LZ |
4357 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
4358 | cgroup_unlock(); | |
a7885eb8 | 4359 | return -EINVAL; |
068b38c1 | 4360 | } |
a7885eb8 | 4361 | |
a7885eb8 | 4362 | memcg->swappiness = val; |
a7885eb8 | 4363 | |
068b38c1 LZ |
4364 | cgroup_unlock(); |
4365 | ||
a7885eb8 KM |
4366 | return 0; |
4367 | } | |
4368 | ||
2e72b634 KS |
4369 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
4370 | { | |
4371 | struct mem_cgroup_threshold_ary *t; | |
4372 | u64 usage; | |
4373 | int i; | |
4374 | ||
4375 | rcu_read_lock(); | |
4376 | if (!swap) | |
2c488db2 | 4377 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 4378 | else |
2c488db2 | 4379 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
4380 | |
4381 | if (!t) | |
4382 | goto unlock; | |
4383 | ||
4384 | usage = mem_cgroup_usage(memcg, swap); | |
4385 | ||
4386 | /* | |
4387 | * current_threshold points to threshold just below usage. | |
4388 | * If it's not true, a threshold was crossed after last | |
4389 | * call of __mem_cgroup_threshold(). | |
4390 | */ | |
5407a562 | 4391 | i = t->current_threshold; |
2e72b634 KS |
4392 | |
4393 | /* | |
4394 | * Iterate backward over array of thresholds starting from | |
4395 | * current_threshold and check if a threshold is crossed. | |
4396 | * If none of thresholds below usage is crossed, we read | |
4397 | * only one element of the array here. | |
4398 | */ | |
4399 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
4400 | eventfd_signal(t->entries[i].eventfd, 1); | |
4401 | ||
4402 | /* i = current_threshold + 1 */ | |
4403 | i++; | |
4404 | ||
4405 | /* | |
4406 | * Iterate forward over array of thresholds starting from | |
4407 | * current_threshold+1 and check if a threshold is crossed. | |
4408 | * If none of thresholds above usage is crossed, we read | |
4409 | * only one element of the array here. | |
4410 | */ | |
4411 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
4412 | eventfd_signal(t->entries[i].eventfd, 1); | |
4413 | ||
4414 | /* Update current_threshold */ | |
5407a562 | 4415 | t->current_threshold = i - 1; |
2e72b634 KS |
4416 | unlock: |
4417 | rcu_read_unlock(); | |
4418 | } | |
4419 | ||
4420 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
4421 | { | |
ad4ca5f4 KS |
4422 | while (memcg) { |
4423 | __mem_cgroup_threshold(memcg, false); | |
4424 | if (do_swap_account) | |
4425 | __mem_cgroup_threshold(memcg, true); | |
4426 | ||
4427 | memcg = parent_mem_cgroup(memcg); | |
4428 | } | |
2e72b634 KS |
4429 | } |
4430 | ||
4431 | static int compare_thresholds(const void *a, const void *b) | |
4432 | { | |
4433 | const struct mem_cgroup_threshold *_a = a; | |
4434 | const struct mem_cgroup_threshold *_b = b; | |
4435 | ||
4436 | return _a->threshold - _b->threshold; | |
4437 | } | |
4438 | ||
7d74b06f | 4439 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *mem) |
9490ff27 KH |
4440 | { |
4441 | struct mem_cgroup_eventfd_list *ev; | |
4442 | ||
4443 | list_for_each_entry(ev, &mem->oom_notify, list) | |
4444 | eventfd_signal(ev->eventfd, 1); | |
4445 | return 0; | |
4446 | } | |
4447 | ||
4448 | static void mem_cgroup_oom_notify(struct mem_cgroup *mem) | |
4449 | { | |
7d74b06f KH |
4450 | struct mem_cgroup *iter; |
4451 | ||
4452 | for_each_mem_cgroup_tree(iter, mem) | |
4453 | mem_cgroup_oom_notify_cb(iter); | |
9490ff27 KH |
4454 | } |
4455 | ||
4456 | static int mem_cgroup_usage_register_event(struct cgroup *cgrp, | |
4457 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
2e72b634 KS |
4458 | { |
4459 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4460 | struct mem_cgroup_thresholds *thresholds; |
4461 | struct mem_cgroup_threshold_ary *new; | |
2e72b634 KS |
4462 | int type = MEMFILE_TYPE(cft->private); |
4463 | u64 threshold, usage; | |
2c488db2 | 4464 | int i, size, ret; |
2e72b634 KS |
4465 | |
4466 | ret = res_counter_memparse_write_strategy(args, &threshold); | |
4467 | if (ret) | |
4468 | return ret; | |
4469 | ||
4470 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 4471 | |
2e72b634 | 4472 | if (type == _MEM) |
2c488db2 | 4473 | thresholds = &memcg->thresholds; |
2e72b634 | 4474 | else if (type == _MEMSWAP) |
2c488db2 | 4475 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4476 | else |
4477 | BUG(); | |
4478 | ||
4479 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4480 | ||
4481 | /* Check if a threshold crossed before adding a new one */ | |
2c488db2 | 4482 | if (thresholds->primary) |
2e72b634 KS |
4483 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4484 | ||
2c488db2 | 4485 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
4486 | |
4487 | /* Allocate memory for new array of thresholds */ | |
2c488db2 | 4488 | new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold), |
2e72b634 | 4489 | GFP_KERNEL); |
2c488db2 | 4490 | if (!new) { |
2e72b634 KS |
4491 | ret = -ENOMEM; |
4492 | goto unlock; | |
4493 | } | |
2c488db2 | 4494 | new->size = size; |
2e72b634 KS |
4495 | |
4496 | /* Copy thresholds (if any) to new array */ | |
2c488db2 KS |
4497 | if (thresholds->primary) { |
4498 | memcpy(new->entries, thresholds->primary->entries, (size - 1) * | |
2e72b634 | 4499 | sizeof(struct mem_cgroup_threshold)); |
2c488db2 KS |
4500 | } |
4501 | ||
2e72b634 | 4502 | /* Add new threshold */ |
2c488db2 KS |
4503 | new->entries[size - 1].eventfd = eventfd; |
4504 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
4505 | |
4506 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
2c488db2 | 4507 | sort(new->entries, size, sizeof(struct mem_cgroup_threshold), |
2e72b634 KS |
4508 | compare_thresholds, NULL); |
4509 | ||
4510 | /* Find current threshold */ | |
2c488db2 | 4511 | new->current_threshold = -1; |
2e72b634 | 4512 | for (i = 0; i < size; i++) { |
2c488db2 | 4513 | if (new->entries[i].threshold < usage) { |
2e72b634 | 4514 | /* |
2c488db2 KS |
4515 | * new->current_threshold will not be used until |
4516 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
4517 | * it here. |
4518 | */ | |
2c488db2 | 4519 | ++new->current_threshold; |
2e72b634 KS |
4520 | } |
4521 | } | |
4522 | ||
2c488db2 KS |
4523 | /* Free old spare buffer and save old primary buffer as spare */ |
4524 | kfree(thresholds->spare); | |
4525 | thresholds->spare = thresholds->primary; | |
4526 | ||
4527 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4528 | |
907860ed | 4529 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4530 | synchronize_rcu(); |
4531 | ||
2e72b634 KS |
4532 | unlock: |
4533 | mutex_unlock(&memcg->thresholds_lock); | |
4534 | ||
4535 | return ret; | |
4536 | } | |
4537 | ||
907860ed | 4538 | static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp, |
9490ff27 | 4539 | struct cftype *cft, struct eventfd_ctx *eventfd) |
2e72b634 KS |
4540 | { |
4541 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4542 | struct mem_cgroup_thresholds *thresholds; |
4543 | struct mem_cgroup_threshold_ary *new; | |
2e72b634 KS |
4544 | int type = MEMFILE_TYPE(cft->private); |
4545 | u64 usage; | |
2c488db2 | 4546 | int i, j, size; |
2e72b634 KS |
4547 | |
4548 | mutex_lock(&memcg->thresholds_lock); | |
4549 | if (type == _MEM) | |
2c488db2 | 4550 | thresholds = &memcg->thresholds; |
2e72b634 | 4551 | else if (type == _MEMSWAP) |
2c488db2 | 4552 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4553 | else |
4554 | BUG(); | |
4555 | ||
4556 | /* | |
4557 | * Something went wrong if we trying to unregister a threshold | |
4558 | * if we don't have thresholds | |
4559 | */ | |
4560 | BUG_ON(!thresholds); | |
4561 | ||
4562 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4563 | ||
4564 | /* Check if a threshold crossed before removing */ | |
4565 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
4566 | ||
4567 | /* Calculate new number of threshold */ | |
2c488db2 KS |
4568 | size = 0; |
4569 | for (i = 0; i < thresholds->primary->size; i++) { | |
4570 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 KS |
4571 | size++; |
4572 | } | |
4573 | ||
2c488db2 | 4574 | new = thresholds->spare; |
907860ed | 4575 | |
2e72b634 KS |
4576 | /* Set thresholds array to NULL if we don't have thresholds */ |
4577 | if (!size) { | |
2c488db2 KS |
4578 | kfree(new); |
4579 | new = NULL; | |
907860ed | 4580 | goto swap_buffers; |
2e72b634 KS |
4581 | } |
4582 | ||
2c488db2 | 4583 | new->size = size; |
2e72b634 KS |
4584 | |
4585 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
4586 | new->current_threshold = -1; |
4587 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
4588 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
4589 | continue; |
4590 | ||
2c488db2 KS |
4591 | new->entries[j] = thresholds->primary->entries[i]; |
4592 | if (new->entries[j].threshold < usage) { | |
2e72b634 | 4593 | /* |
2c488db2 | 4594 | * new->current_threshold will not be used |
2e72b634 KS |
4595 | * until rcu_assign_pointer(), so it's safe to increment |
4596 | * it here. | |
4597 | */ | |
2c488db2 | 4598 | ++new->current_threshold; |
2e72b634 KS |
4599 | } |
4600 | j++; | |
4601 | } | |
4602 | ||
907860ed | 4603 | swap_buffers: |
2c488db2 KS |
4604 | /* Swap primary and spare array */ |
4605 | thresholds->spare = thresholds->primary; | |
4606 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4607 | |
907860ed | 4608 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4609 | synchronize_rcu(); |
4610 | ||
2e72b634 | 4611 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 4612 | } |
c1e862c1 | 4613 | |
9490ff27 KH |
4614 | static int mem_cgroup_oom_register_event(struct cgroup *cgrp, |
4615 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
4616 | { | |
4617 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4618 | struct mem_cgroup_eventfd_list *event; | |
4619 | int type = MEMFILE_TYPE(cft->private); | |
4620 | ||
4621 | BUG_ON(type != _OOM_TYPE); | |
4622 | event = kmalloc(sizeof(*event), GFP_KERNEL); | |
4623 | if (!event) | |
4624 | return -ENOMEM; | |
4625 | ||
1af8efe9 | 4626 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4627 | |
4628 | event->eventfd = eventfd; | |
4629 | list_add(&event->list, &memcg->oom_notify); | |
4630 | ||
4631 | /* already in OOM ? */ | |
79dfdacc | 4632 | if (atomic_read(&memcg->under_oom)) |
9490ff27 | 4633 | eventfd_signal(eventfd, 1); |
1af8efe9 | 4634 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4635 | |
4636 | return 0; | |
4637 | } | |
4638 | ||
907860ed | 4639 | static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp, |
9490ff27 KH |
4640 | struct cftype *cft, struct eventfd_ctx *eventfd) |
4641 | { | |
4642 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4643 | struct mem_cgroup_eventfd_list *ev, *tmp; | |
4644 | int type = MEMFILE_TYPE(cft->private); | |
4645 | ||
4646 | BUG_ON(type != _OOM_TYPE); | |
4647 | ||
1af8efe9 | 4648 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4649 | |
4650 | list_for_each_entry_safe(ev, tmp, &mem->oom_notify, list) { | |
4651 | if (ev->eventfd == eventfd) { | |
4652 | list_del(&ev->list); | |
4653 | kfree(ev); | |
4654 | } | |
4655 | } | |
4656 | ||
1af8efe9 | 4657 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4658 | } |
4659 | ||
3c11ecf4 KH |
4660 | static int mem_cgroup_oom_control_read(struct cgroup *cgrp, |
4661 | struct cftype *cft, struct cgroup_map_cb *cb) | |
4662 | { | |
4663 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4664 | ||
4665 | cb->fill(cb, "oom_kill_disable", mem->oom_kill_disable); | |
4666 | ||
79dfdacc | 4667 | if (atomic_read(&mem->under_oom)) |
3c11ecf4 KH |
4668 | cb->fill(cb, "under_oom", 1); |
4669 | else | |
4670 | cb->fill(cb, "under_oom", 0); | |
4671 | return 0; | |
4672 | } | |
4673 | ||
3c11ecf4 KH |
4674 | static int mem_cgroup_oom_control_write(struct cgroup *cgrp, |
4675 | struct cftype *cft, u64 val) | |
4676 | { | |
4677 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4678 | struct mem_cgroup *parent; | |
4679 | ||
4680 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
4681 | if (!cgrp->parent || !((val == 0) || (val == 1))) | |
4682 | return -EINVAL; | |
4683 | ||
4684 | parent = mem_cgroup_from_cont(cgrp->parent); | |
4685 | ||
4686 | cgroup_lock(); | |
4687 | /* oom-kill-disable is a flag for subhierarchy. */ | |
4688 | if ((parent->use_hierarchy) || | |
4689 | (mem->use_hierarchy && !list_empty(&cgrp->children))) { | |
4690 | cgroup_unlock(); | |
4691 | return -EINVAL; | |
4692 | } | |
4693 | mem->oom_kill_disable = val; | |
4d845ebf KH |
4694 | if (!val) |
4695 | memcg_oom_recover(mem); | |
3c11ecf4 KH |
4696 | cgroup_unlock(); |
4697 | return 0; | |
4698 | } | |
4699 | ||
406eb0c9 YH |
4700 | #ifdef CONFIG_NUMA |
4701 | static const struct file_operations mem_control_numa_stat_file_operations = { | |
4702 | .read = seq_read, | |
4703 | .llseek = seq_lseek, | |
4704 | .release = single_release, | |
4705 | }; | |
4706 | ||
4707 | static int mem_control_numa_stat_open(struct inode *unused, struct file *file) | |
4708 | { | |
4709 | struct cgroup *cont = file->f_dentry->d_parent->d_fsdata; | |
4710 | ||
4711 | file->f_op = &mem_control_numa_stat_file_operations; | |
4712 | return single_open(file, mem_control_numa_stat_show, cont); | |
4713 | } | |
4714 | #endif /* CONFIG_NUMA */ | |
4715 | ||
82f9d486 KH |
4716 | static int mem_cgroup_vmscan_stat_read(struct cgroup *cgrp, |
4717 | struct cftype *cft, | |
4718 | struct cgroup_map_cb *cb) | |
4719 | { | |
4720 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4721 | char string[64]; | |
4722 | int i; | |
4723 | ||
4724 | for (i = 0; i < NR_SCANSTATS; i++) { | |
4725 | strcpy(string, scanstat_string[i]); | |
4726 | strcat(string, SCANSTAT_WORD_LIMIT); | |
4727 | cb->fill(cb, string, mem->scanstat.stats[SCAN_BY_LIMIT][i]); | |
4728 | } | |
4729 | ||
4730 | for (i = 0; i < NR_SCANSTATS; i++) { | |
4731 | strcpy(string, scanstat_string[i]); | |
4732 | strcat(string, SCANSTAT_WORD_SYSTEM); | |
4733 | cb->fill(cb, string, mem->scanstat.stats[SCAN_BY_SYSTEM][i]); | |
4734 | } | |
4735 | ||
4736 | for (i = 0; i < NR_SCANSTATS; i++) { | |
4737 | strcpy(string, scanstat_string[i]); | |
4738 | strcat(string, SCANSTAT_WORD_LIMIT); | |
4739 | strcat(string, SCANSTAT_WORD_HIERARCHY); | |
4740 | cb->fill(cb, string, mem->scanstat.rootstats[SCAN_BY_LIMIT][i]); | |
4741 | } | |
4742 | for (i = 0; i < NR_SCANSTATS; i++) { | |
4743 | strcpy(string, scanstat_string[i]); | |
4744 | strcat(string, SCANSTAT_WORD_SYSTEM); | |
4745 | strcat(string, SCANSTAT_WORD_HIERARCHY); | |
4746 | cb->fill(cb, string, mem->scanstat.rootstats[SCAN_BY_SYSTEM][i]); | |
4747 | } | |
4748 | return 0; | |
4749 | } | |
4750 | ||
4751 | static int mem_cgroup_reset_vmscan_stat(struct cgroup *cgrp, | |
4752 | unsigned int event) | |
4753 | { | |
4754 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4755 | ||
4756 | spin_lock(&mem->scanstat.lock); | |
4757 | memset(&mem->scanstat.stats, 0, sizeof(mem->scanstat.stats)); | |
4758 | memset(&mem->scanstat.rootstats, 0, sizeof(mem->scanstat.rootstats)); | |
4759 | spin_unlock(&mem->scanstat.lock); | |
4760 | return 0; | |
4761 | } | |
4762 | ||
4763 | ||
8cdea7c0 BS |
4764 | static struct cftype mem_cgroup_files[] = { |
4765 | { | |
0eea1030 | 4766 | .name = "usage_in_bytes", |
8c7c6e34 | 4767 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
2c3daa72 | 4768 | .read_u64 = mem_cgroup_read, |
9490ff27 KH |
4769 | .register_event = mem_cgroup_usage_register_event, |
4770 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8cdea7c0 | 4771 | }, |
c84872e1 PE |
4772 | { |
4773 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 4774 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
29f2a4da | 4775 | .trigger = mem_cgroup_reset, |
c84872e1 PE |
4776 | .read_u64 = mem_cgroup_read, |
4777 | }, | |
8cdea7c0 | 4778 | { |
0eea1030 | 4779 | .name = "limit_in_bytes", |
8c7c6e34 | 4780 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
856c13aa | 4781 | .write_string = mem_cgroup_write, |
2c3daa72 | 4782 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 4783 | }, |
296c81d8 BS |
4784 | { |
4785 | .name = "soft_limit_in_bytes", | |
4786 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
4787 | .write_string = mem_cgroup_write, | |
4788 | .read_u64 = mem_cgroup_read, | |
4789 | }, | |
8cdea7c0 BS |
4790 | { |
4791 | .name = "failcnt", | |
8c7c6e34 | 4792 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
29f2a4da | 4793 | .trigger = mem_cgroup_reset, |
2c3daa72 | 4794 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 4795 | }, |
d2ceb9b7 KH |
4796 | { |
4797 | .name = "stat", | |
c64745cf | 4798 | .read_map = mem_control_stat_show, |
d2ceb9b7 | 4799 | }, |
c1e862c1 KH |
4800 | { |
4801 | .name = "force_empty", | |
4802 | .trigger = mem_cgroup_force_empty_write, | |
4803 | }, | |
18f59ea7 BS |
4804 | { |
4805 | .name = "use_hierarchy", | |
4806 | .write_u64 = mem_cgroup_hierarchy_write, | |
4807 | .read_u64 = mem_cgroup_hierarchy_read, | |
4808 | }, | |
a7885eb8 KM |
4809 | { |
4810 | .name = "swappiness", | |
4811 | .read_u64 = mem_cgroup_swappiness_read, | |
4812 | .write_u64 = mem_cgroup_swappiness_write, | |
4813 | }, | |
7dc74be0 DN |
4814 | { |
4815 | .name = "move_charge_at_immigrate", | |
4816 | .read_u64 = mem_cgroup_move_charge_read, | |
4817 | .write_u64 = mem_cgroup_move_charge_write, | |
4818 | }, | |
9490ff27 KH |
4819 | { |
4820 | .name = "oom_control", | |
3c11ecf4 KH |
4821 | .read_map = mem_cgroup_oom_control_read, |
4822 | .write_u64 = mem_cgroup_oom_control_write, | |
9490ff27 KH |
4823 | .register_event = mem_cgroup_oom_register_event, |
4824 | .unregister_event = mem_cgroup_oom_unregister_event, | |
4825 | .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), | |
4826 | }, | |
406eb0c9 YH |
4827 | #ifdef CONFIG_NUMA |
4828 | { | |
4829 | .name = "numa_stat", | |
4830 | .open = mem_control_numa_stat_open, | |
89577127 | 4831 | .mode = S_IRUGO, |
406eb0c9 YH |
4832 | }, |
4833 | #endif | |
82f9d486 KH |
4834 | { |
4835 | .name = "vmscan_stat", | |
4836 | .read_map = mem_cgroup_vmscan_stat_read, | |
4837 | .trigger = mem_cgroup_reset_vmscan_stat, | |
4838 | }, | |
8cdea7c0 BS |
4839 | }; |
4840 | ||
8c7c6e34 KH |
4841 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4842 | static struct cftype memsw_cgroup_files[] = { | |
4843 | { | |
4844 | .name = "memsw.usage_in_bytes", | |
4845 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
4846 | .read_u64 = mem_cgroup_read, | |
9490ff27 KH |
4847 | .register_event = mem_cgroup_usage_register_event, |
4848 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8c7c6e34 KH |
4849 | }, |
4850 | { | |
4851 | .name = "memsw.max_usage_in_bytes", | |
4852 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
4853 | .trigger = mem_cgroup_reset, | |
4854 | .read_u64 = mem_cgroup_read, | |
4855 | }, | |
4856 | { | |
4857 | .name = "memsw.limit_in_bytes", | |
4858 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
4859 | .write_string = mem_cgroup_write, | |
4860 | .read_u64 = mem_cgroup_read, | |
4861 | }, | |
4862 | { | |
4863 | .name = "memsw.failcnt", | |
4864 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
4865 | .trigger = mem_cgroup_reset, | |
4866 | .read_u64 = mem_cgroup_read, | |
4867 | }, | |
4868 | }; | |
4869 | ||
4870 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4871 | { | |
4872 | if (!do_swap_account) | |
4873 | return 0; | |
4874 | return cgroup_add_files(cont, ss, memsw_cgroup_files, | |
4875 | ARRAY_SIZE(memsw_cgroup_files)); | |
4876 | }; | |
4877 | #else | |
4878 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4879 | { | |
4880 | return 0; | |
4881 | } | |
4882 | #endif | |
4883 | ||
6d12e2d8 KH |
4884 | static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
4885 | { | |
4886 | struct mem_cgroup_per_node *pn; | |
1ecaab2b | 4887 | struct mem_cgroup_per_zone *mz; |
b69408e8 | 4888 | enum lru_list l; |
41e3355d | 4889 | int zone, tmp = node; |
1ecaab2b KH |
4890 | /* |
4891 | * This routine is called against possible nodes. | |
4892 | * But it's BUG to call kmalloc() against offline node. | |
4893 | * | |
4894 | * TODO: this routine can waste much memory for nodes which will | |
4895 | * never be onlined. It's better to use memory hotplug callback | |
4896 | * function. | |
4897 | */ | |
41e3355d KH |
4898 | if (!node_state(node, N_NORMAL_MEMORY)) |
4899 | tmp = -1; | |
17295c88 | 4900 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); |
6d12e2d8 KH |
4901 | if (!pn) |
4902 | return 1; | |
1ecaab2b | 4903 | |
6d12e2d8 | 4904 | mem->info.nodeinfo[node] = pn; |
1ecaab2b KH |
4905 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
4906 | mz = &pn->zoneinfo[zone]; | |
b69408e8 CL |
4907 | for_each_lru(l) |
4908 | INIT_LIST_HEAD(&mz->lists[l]); | |
f64c3f54 | 4909 | mz->usage_in_excess = 0; |
4e416953 BS |
4910 | mz->on_tree = false; |
4911 | mz->mem = mem; | |
1ecaab2b | 4912 | } |
6d12e2d8 KH |
4913 | return 0; |
4914 | } | |
4915 | ||
1ecaab2b KH |
4916 | static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
4917 | { | |
4918 | kfree(mem->info.nodeinfo[node]); | |
4919 | } | |
4920 | ||
33327948 KH |
4921 | static struct mem_cgroup *mem_cgroup_alloc(void) |
4922 | { | |
4923 | struct mem_cgroup *mem; | |
c62b1a3b | 4924 | int size = sizeof(struct mem_cgroup); |
33327948 | 4925 | |
c62b1a3b | 4926 | /* Can be very big if MAX_NUMNODES is very big */ |
c8dad2bb | 4927 | if (size < PAGE_SIZE) |
17295c88 | 4928 | mem = kzalloc(size, GFP_KERNEL); |
33327948 | 4929 | else |
17295c88 | 4930 | mem = vzalloc(size); |
33327948 | 4931 | |
e7bbcdf3 DC |
4932 | if (!mem) |
4933 | return NULL; | |
4934 | ||
c62b1a3b | 4935 | mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu); |
d2e61b8d DC |
4936 | if (!mem->stat) |
4937 | goto out_free; | |
711d3d2c | 4938 | spin_lock_init(&mem->pcp_counter_lock); |
33327948 | 4939 | return mem; |
d2e61b8d DC |
4940 | |
4941 | out_free: | |
4942 | if (size < PAGE_SIZE) | |
4943 | kfree(mem); | |
4944 | else | |
4945 | vfree(mem); | |
4946 | return NULL; | |
33327948 KH |
4947 | } |
4948 | ||
8c7c6e34 KH |
4949 | /* |
4950 | * At destroying mem_cgroup, references from swap_cgroup can remain. | |
4951 | * (scanning all at force_empty is too costly...) | |
4952 | * | |
4953 | * Instead of clearing all references at force_empty, we remember | |
4954 | * the number of reference from swap_cgroup and free mem_cgroup when | |
4955 | * it goes down to 0. | |
4956 | * | |
8c7c6e34 KH |
4957 | * Removal of cgroup itself succeeds regardless of refs from swap. |
4958 | */ | |
4959 | ||
a7ba0eef | 4960 | static void __mem_cgroup_free(struct mem_cgroup *mem) |
33327948 | 4961 | { |
08e552c6 KH |
4962 | int node; |
4963 | ||
f64c3f54 | 4964 | mem_cgroup_remove_from_trees(mem); |
04046e1a KH |
4965 | free_css_id(&mem_cgroup_subsys, &mem->css); |
4966 | ||
08e552c6 KH |
4967 | for_each_node_state(node, N_POSSIBLE) |
4968 | free_mem_cgroup_per_zone_info(mem, node); | |
4969 | ||
c62b1a3b KH |
4970 | free_percpu(mem->stat); |
4971 | if (sizeof(struct mem_cgroup) < PAGE_SIZE) | |
33327948 KH |
4972 | kfree(mem); |
4973 | else | |
4974 | vfree(mem); | |
4975 | } | |
4976 | ||
8c7c6e34 KH |
4977 | static void mem_cgroup_get(struct mem_cgroup *mem) |
4978 | { | |
4979 | atomic_inc(&mem->refcnt); | |
4980 | } | |
4981 | ||
483c30b5 | 4982 | static void __mem_cgroup_put(struct mem_cgroup *mem, int count) |
8c7c6e34 | 4983 | { |
483c30b5 | 4984 | if (atomic_sub_and_test(count, &mem->refcnt)) { |
7bcc1bb1 | 4985 | struct mem_cgroup *parent = parent_mem_cgroup(mem); |
a7ba0eef | 4986 | __mem_cgroup_free(mem); |
7bcc1bb1 DN |
4987 | if (parent) |
4988 | mem_cgroup_put(parent); | |
4989 | } | |
8c7c6e34 KH |
4990 | } |
4991 | ||
483c30b5 DN |
4992 | static void mem_cgroup_put(struct mem_cgroup *mem) |
4993 | { | |
4994 | __mem_cgroup_put(mem, 1); | |
4995 | } | |
4996 | ||
7bcc1bb1 DN |
4997 | /* |
4998 | * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. | |
4999 | */ | |
5000 | static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem) | |
5001 | { | |
5002 | if (!mem->res.parent) | |
5003 | return NULL; | |
5004 | return mem_cgroup_from_res_counter(mem->res.parent, res); | |
5005 | } | |
33327948 | 5006 | |
c077719b KH |
5007 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
5008 | static void __init enable_swap_cgroup(void) | |
5009 | { | |
f8d66542 | 5010 | if (!mem_cgroup_disabled() && really_do_swap_account) |
c077719b KH |
5011 | do_swap_account = 1; |
5012 | } | |
5013 | #else | |
5014 | static void __init enable_swap_cgroup(void) | |
5015 | { | |
5016 | } | |
5017 | #endif | |
5018 | ||
f64c3f54 BS |
5019 | static int mem_cgroup_soft_limit_tree_init(void) |
5020 | { | |
5021 | struct mem_cgroup_tree_per_node *rtpn; | |
5022 | struct mem_cgroup_tree_per_zone *rtpz; | |
5023 | int tmp, node, zone; | |
5024 | ||
5025 | for_each_node_state(node, N_POSSIBLE) { | |
5026 | tmp = node; | |
5027 | if (!node_state(node, N_NORMAL_MEMORY)) | |
5028 | tmp = -1; | |
5029 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, tmp); | |
5030 | if (!rtpn) | |
5031 | return 1; | |
5032 | ||
5033 | soft_limit_tree.rb_tree_per_node[node] = rtpn; | |
5034 | ||
5035 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
5036 | rtpz = &rtpn->rb_tree_per_zone[zone]; | |
5037 | rtpz->rb_root = RB_ROOT; | |
5038 | spin_lock_init(&rtpz->lock); | |
5039 | } | |
5040 | } | |
5041 | return 0; | |
5042 | } | |
5043 | ||
0eb253e2 | 5044 | static struct cgroup_subsys_state * __ref |
8cdea7c0 BS |
5045 | mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) |
5046 | { | |
28dbc4b6 | 5047 | struct mem_cgroup *mem, *parent; |
04046e1a | 5048 | long error = -ENOMEM; |
6d12e2d8 | 5049 | int node; |
8cdea7c0 | 5050 | |
c8dad2bb JB |
5051 | mem = mem_cgroup_alloc(); |
5052 | if (!mem) | |
04046e1a | 5053 | return ERR_PTR(error); |
78fb7466 | 5054 | |
6d12e2d8 KH |
5055 | for_each_node_state(node, N_POSSIBLE) |
5056 | if (alloc_mem_cgroup_per_zone_info(mem, node)) | |
5057 | goto free_out; | |
f64c3f54 | 5058 | |
c077719b | 5059 | /* root ? */ |
28dbc4b6 | 5060 | if (cont->parent == NULL) { |
cdec2e42 | 5061 | int cpu; |
c077719b | 5062 | enable_swap_cgroup(); |
28dbc4b6 | 5063 | parent = NULL; |
4b3bde4c | 5064 | root_mem_cgroup = mem; |
f64c3f54 BS |
5065 | if (mem_cgroup_soft_limit_tree_init()) |
5066 | goto free_out; | |
cdec2e42 KH |
5067 | for_each_possible_cpu(cpu) { |
5068 | struct memcg_stock_pcp *stock = | |
5069 | &per_cpu(memcg_stock, cpu); | |
5070 | INIT_WORK(&stock->work, drain_local_stock); | |
5071 | } | |
711d3d2c | 5072 | hotcpu_notifier(memcg_cpu_hotplug_callback, 0); |
18f59ea7 | 5073 | } else { |
28dbc4b6 | 5074 | parent = mem_cgroup_from_cont(cont->parent); |
18f59ea7 | 5075 | mem->use_hierarchy = parent->use_hierarchy; |
3c11ecf4 | 5076 | mem->oom_kill_disable = parent->oom_kill_disable; |
18f59ea7 | 5077 | } |
28dbc4b6 | 5078 | |
18f59ea7 BS |
5079 | if (parent && parent->use_hierarchy) { |
5080 | res_counter_init(&mem->res, &parent->res); | |
5081 | res_counter_init(&mem->memsw, &parent->memsw); | |
7bcc1bb1 DN |
5082 | /* |
5083 | * We increment refcnt of the parent to ensure that we can | |
5084 | * safely access it on res_counter_charge/uncharge. | |
5085 | * This refcnt will be decremented when freeing this | |
5086 | * mem_cgroup(see mem_cgroup_put). | |
5087 | */ | |
5088 | mem_cgroup_get(parent); | |
18f59ea7 BS |
5089 | } else { |
5090 | res_counter_init(&mem->res, NULL); | |
5091 | res_counter_init(&mem->memsw, NULL); | |
5092 | } | |
04046e1a | 5093 | mem->last_scanned_child = 0; |
889976db | 5094 | mem->last_scanned_node = MAX_NUMNODES; |
9490ff27 | 5095 | INIT_LIST_HEAD(&mem->oom_notify); |
6d61ef40 | 5096 | |
a7885eb8 | 5097 | if (parent) |
1f4c025b | 5098 | mem->swappiness = mem_cgroup_swappiness(parent); |
a7ba0eef | 5099 | atomic_set(&mem->refcnt, 1); |
7dc74be0 | 5100 | mem->move_charge_at_immigrate = 0; |
2e72b634 | 5101 | mutex_init(&mem->thresholds_lock); |
82f9d486 | 5102 | spin_lock_init(&mem->scanstat.lock); |
8cdea7c0 | 5103 | return &mem->css; |
6d12e2d8 | 5104 | free_out: |
a7ba0eef | 5105 | __mem_cgroup_free(mem); |
4b3bde4c | 5106 | root_mem_cgroup = NULL; |
04046e1a | 5107 | return ERR_PTR(error); |
8cdea7c0 BS |
5108 | } |
5109 | ||
ec64f515 | 5110 | static int mem_cgroup_pre_destroy(struct cgroup_subsys *ss, |
df878fb0 KH |
5111 | struct cgroup *cont) |
5112 | { | |
5113 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); | |
ec64f515 KH |
5114 | |
5115 | return mem_cgroup_force_empty(mem, false); | |
df878fb0 KH |
5116 | } |
5117 | ||
8cdea7c0 BS |
5118 | static void mem_cgroup_destroy(struct cgroup_subsys *ss, |
5119 | struct cgroup *cont) | |
5120 | { | |
c268e994 | 5121 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
c268e994 | 5122 | |
c268e994 | 5123 | mem_cgroup_put(mem); |
8cdea7c0 BS |
5124 | } |
5125 | ||
5126 | static int mem_cgroup_populate(struct cgroup_subsys *ss, | |
5127 | struct cgroup *cont) | |
5128 | { | |
8c7c6e34 KH |
5129 | int ret; |
5130 | ||
5131 | ret = cgroup_add_files(cont, ss, mem_cgroup_files, | |
5132 | ARRAY_SIZE(mem_cgroup_files)); | |
5133 | ||
5134 | if (!ret) | |
5135 | ret = register_memsw_files(cont, ss); | |
5136 | return ret; | |
8cdea7c0 BS |
5137 | } |
5138 | ||
02491447 | 5139 | #ifdef CONFIG_MMU |
7dc74be0 | 5140 | /* Handlers for move charge at task migration. */ |
854ffa8d DN |
5141 | #define PRECHARGE_COUNT_AT_ONCE 256 |
5142 | static int mem_cgroup_do_precharge(unsigned long count) | |
7dc74be0 | 5143 | { |
854ffa8d DN |
5144 | int ret = 0; |
5145 | int batch_count = PRECHARGE_COUNT_AT_ONCE; | |
4ffef5fe DN |
5146 | struct mem_cgroup *mem = mc.to; |
5147 | ||
854ffa8d DN |
5148 | if (mem_cgroup_is_root(mem)) { |
5149 | mc.precharge += count; | |
5150 | /* we don't need css_get for root */ | |
5151 | return ret; | |
5152 | } | |
5153 | /* try to charge at once */ | |
5154 | if (count > 1) { | |
5155 | struct res_counter *dummy; | |
5156 | /* | |
5157 | * "mem" cannot be under rmdir() because we've already checked | |
5158 | * by cgroup_lock_live_cgroup() that it is not removed and we | |
5159 | * are still under the same cgroup_mutex. So we can postpone | |
5160 | * css_get(). | |
5161 | */ | |
5162 | if (res_counter_charge(&mem->res, PAGE_SIZE * count, &dummy)) | |
5163 | goto one_by_one; | |
5164 | if (do_swap_account && res_counter_charge(&mem->memsw, | |
5165 | PAGE_SIZE * count, &dummy)) { | |
5166 | res_counter_uncharge(&mem->res, PAGE_SIZE * count); | |
5167 | goto one_by_one; | |
5168 | } | |
5169 | mc.precharge += count; | |
854ffa8d DN |
5170 | return ret; |
5171 | } | |
5172 | one_by_one: | |
5173 | /* fall back to one by one charge */ | |
5174 | while (count--) { | |
5175 | if (signal_pending(current)) { | |
5176 | ret = -EINTR; | |
5177 | break; | |
5178 | } | |
5179 | if (!batch_count--) { | |
5180 | batch_count = PRECHARGE_COUNT_AT_ONCE; | |
5181 | cond_resched(); | |
5182 | } | |
7ec99d62 | 5183 | ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, 1, &mem, false); |
854ffa8d DN |
5184 | if (ret || !mem) |
5185 | /* mem_cgroup_clear_mc() will do uncharge later */ | |
5186 | return -ENOMEM; | |
5187 | mc.precharge++; | |
5188 | } | |
4ffef5fe DN |
5189 | return ret; |
5190 | } | |
5191 | ||
5192 | /** | |
5193 | * is_target_pte_for_mc - check a pte whether it is valid for move charge | |
5194 | * @vma: the vma the pte to be checked belongs | |
5195 | * @addr: the address corresponding to the pte to be checked | |
5196 | * @ptent: the pte to be checked | |
02491447 | 5197 | * @target: the pointer the target page or swap ent will be stored(can be NULL) |
4ffef5fe DN |
5198 | * |
5199 | * Returns | |
5200 | * 0(MC_TARGET_NONE): if the pte is not a target for move charge. | |
5201 | * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for | |
5202 | * move charge. if @target is not NULL, the page is stored in target->page | |
5203 | * with extra refcnt got(Callers should handle it). | |
02491447 DN |
5204 | * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a |
5205 | * target for charge migration. if @target is not NULL, the entry is stored | |
5206 | * in target->ent. | |
4ffef5fe DN |
5207 | * |
5208 | * Called with pte lock held. | |
5209 | */ | |
4ffef5fe DN |
5210 | union mc_target { |
5211 | struct page *page; | |
02491447 | 5212 | swp_entry_t ent; |
4ffef5fe DN |
5213 | }; |
5214 | ||
4ffef5fe DN |
5215 | enum mc_target_type { |
5216 | MC_TARGET_NONE, /* not used */ | |
5217 | MC_TARGET_PAGE, | |
02491447 | 5218 | MC_TARGET_SWAP, |
4ffef5fe DN |
5219 | }; |
5220 | ||
90254a65 DN |
5221 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
5222 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 5223 | { |
90254a65 | 5224 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 5225 | |
90254a65 DN |
5226 | if (!page || !page_mapped(page)) |
5227 | return NULL; | |
5228 | if (PageAnon(page)) { | |
5229 | /* we don't move shared anon */ | |
5230 | if (!move_anon() || page_mapcount(page) > 2) | |
5231 | return NULL; | |
87946a72 DN |
5232 | } else if (!move_file()) |
5233 | /* we ignore mapcount for file pages */ | |
90254a65 DN |
5234 | return NULL; |
5235 | if (!get_page_unless_zero(page)) | |
5236 | return NULL; | |
5237 | ||
5238 | return page; | |
5239 | } | |
5240 | ||
5241 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
5242 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5243 | { | |
5244 | int usage_count; | |
5245 | struct page *page = NULL; | |
5246 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
5247 | ||
5248 | if (!move_anon() || non_swap_entry(ent)) | |
5249 | return NULL; | |
5250 | usage_count = mem_cgroup_count_swap_user(ent, &page); | |
5251 | if (usage_count > 1) { /* we don't move shared anon */ | |
02491447 DN |
5252 | if (page) |
5253 | put_page(page); | |
90254a65 | 5254 | return NULL; |
02491447 | 5255 | } |
90254a65 DN |
5256 | if (do_swap_account) |
5257 | entry->val = ent.val; | |
5258 | ||
5259 | return page; | |
5260 | } | |
5261 | ||
87946a72 DN |
5262 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
5263 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5264 | { | |
5265 | struct page *page = NULL; | |
5266 | struct inode *inode; | |
5267 | struct address_space *mapping; | |
5268 | pgoff_t pgoff; | |
5269 | ||
5270 | if (!vma->vm_file) /* anonymous vma */ | |
5271 | return NULL; | |
5272 | if (!move_file()) | |
5273 | return NULL; | |
5274 | ||
5275 | inode = vma->vm_file->f_path.dentry->d_inode; | |
5276 | mapping = vma->vm_file->f_mapping; | |
5277 | if (pte_none(ptent)) | |
5278 | pgoff = linear_page_index(vma, addr); | |
5279 | else /* pte_file(ptent) is true */ | |
5280 | pgoff = pte_to_pgoff(ptent); | |
5281 | ||
5282 | /* page is moved even if it's not RSS of this task(page-faulted). */ | |
aa3b1895 HD |
5283 | page = find_get_page(mapping, pgoff); |
5284 | ||
5285 | #ifdef CONFIG_SWAP | |
5286 | /* shmem/tmpfs may report page out on swap: account for that too. */ | |
5287 | if (radix_tree_exceptional_entry(page)) { | |
5288 | swp_entry_t swap = radix_to_swp_entry(page); | |
87946a72 | 5289 | if (do_swap_account) |
aa3b1895 HD |
5290 | *entry = swap; |
5291 | page = find_get_page(&swapper_space, swap.val); | |
87946a72 | 5292 | } |
aa3b1895 | 5293 | #endif |
87946a72 DN |
5294 | return page; |
5295 | } | |
5296 | ||
90254a65 DN |
5297 | static int is_target_pte_for_mc(struct vm_area_struct *vma, |
5298 | unsigned long addr, pte_t ptent, union mc_target *target) | |
5299 | { | |
5300 | struct page *page = NULL; | |
5301 | struct page_cgroup *pc; | |
5302 | int ret = 0; | |
5303 | swp_entry_t ent = { .val = 0 }; | |
5304 | ||
5305 | if (pte_present(ptent)) | |
5306 | page = mc_handle_present_pte(vma, addr, ptent); | |
5307 | else if (is_swap_pte(ptent)) | |
5308 | page = mc_handle_swap_pte(vma, addr, ptent, &ent); | |
87946a72 DN |
5309 | else if (pte_none(ptent) || pte_file(ptent)) |
5310 | page = mc_handle_file_pte(vma, addr, ptent, &ent); | |
90254a65 DN |
5311 | |
5312 | if (!page && !ent.val) | |
5313 | return 0; | |
02491447 DN |
5314 | if (page) { |
5315 | pc = lookup_page_cgroup(page); | |
5316 | /* | |
5317 | * Do only loose check w/o page_cgroup lock. | |
5318 | * mem_cgroup_move_account() checks the pc is valid or not under | |
5319 | * the lock. | |
5320 | */ | |
5321 | if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { | |
5322 | ret = MC_TARGET_PAGE; | |
5323 | if (target) | |
5324 | target->page = page; | |
5325 | } | |
5326 | if (!ret || !target) | |
5327 | put_page(page); | |
5328 | } | |
90254a65 DN |
5329 | /* There is a swap entry and a page doesn't exist or isn't charged */ |
5330 | if (ent.val && !ret && | |
7f0f1546 KH |
5331 | css_id(&mc.from->css) == lookup_swap_cgroup(ent)) { |
5332 | ret = MC_TARGET_SWAP; | |
5333 | if (target) | |
5334 | target->ent = ent; | |
4ffef5fe | 5335 | } |
4ffef5fe DN |
5336 | return ret; |
5337 | } | |
5338 | ||
5339 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, | |
5340 | unsigned long addr, unsigned long end, | |
5341 | struct mm_walk *walk) | |
5342 | { | |
5343 | struct vm_area_struct *vma = walk->private; | |
5344 | pte_t *pte; | |
5345 | spinlock_t *ptl; | |
5346 | ||
03319327 DH |
5347 | split_huge_page_pmd(walk->mm, pmd); |
5348 | ||
4ffef5fe DN |
5349 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
5350 | for (; addr != end; pte++, addr += PAGE_SIZE) | |
5351 | if (is_target_pte_for_mc(vma, addr, *pte, NULL)) | |
5352 | mc.precharge++; /* increment precharge temporarily */ | |
5353 | pte_unmap_unlock(pte - 1, ptl); | |
5354 | cond_resched(); | |
5355 | ||
7dc74be0 DN |
5356 | return 0; |
5357 | } | |
5358 | ||
4ffef5fe DN |
5359 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
5360 | { | |
5361 | unsigned long precharge; | |
5362 | struct vm_area_struct *vma; | |
5363 | ||
dfe076b0 | 5364 | down_read(&mm->mmap_sem); |
4ffef5fe DN |
5365 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5366 | struct mm_walk mem_cgroup_count_precharge_walk = { | |
5367 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
5368 | .mm = mm, | |
5369 | .private = vma, | |
5370 | }; | |
5371 | if (is_vm_hugetlb_page(vma)) | |
5372 | continue; | |
4ffef5fe DN |
5373 | walk_page_range(vma->vm_start, vma->vm_end, |
5374 | &mem_cgroup_count_precharge_walk); | |
5375 | } | |
dfe076b0 | 5376 | up_read(&mm->mmap_sem); |
4ffef5fe DN |
5377 | |
5378 | precharge = mc.precharge; | |
5379 | mc.precharge = 0; | |
5380 | ||
5381 | return precharge; | |
5382 | } | |
5383 | ||
4ffef5fe DN |
5384 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
5385 | { | |
dfe076b0 DN |
5386 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
5387 | ||
5388 | VM_BUG_ON(mc.moving_task); | |
5389 | mc.moving_task = current; | |
5390 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
5391 | } |
5392 | ||
dfe076b0 DN |
5393 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
5394 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 5395 | { |
2bd9bb20 KH |
5396 | struct mem_cgroup *from = mc.from; |
5397 | struct mem_cgroup *to = mc.to; | |
5398 | ||
4ffef5fe | 5399 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d DN |
5400 | if (mc.precharge) { |
5401 | __mem_cgroup_cancel_charge(mc.to, mc.precharge); | |
5402 | mc.precharge = 0; | |
5403 | } | |
5404 | /* | |
5405 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
5406 | * we must uncharge here. | |
5407 | */ | |
5408 | if (mc.moved_charge) { | |
5409 | __mem_cgroup_cancel_charge(mc.from, mc.moved_charge); | |
5410 | mc.moved_charge = 0; | |
4ffef5fe | 5411 | } |
483c30b5 DN |
5412 | /* we must fixup refcnts and charges */ |
5413 | if (mc.moved_swap) { | |
483c30b5 DN |
5414 | /* uncharge swap account from the old cgroup */ |
5415 | if (!mem_cgroup_is_root(mc.from)) | |
5416 | res_counter_uncharge(&mc.from->memsw, | |
5417 | PAGE_SIZE * mc.moved_swap); | |
5418 | __mem_cgroup_put(mc.from, mc.moved_swap); | |
5419 | ||
5420 | if (!mem_cgroup_is_root(mc.to)) { | |
5421 | /* | |
5422 | * we charged both to->res and to->memsw, so we should | |
5423 | * uncharge to->res. | |
5424 | */ | |
5425 | res_counter_uncharge(&mc.to->res, | |
5426 | PAGE_SIZE * mc.moved_swap); | |
483c30b5 DN |
5427 | } |
5428 | /* we've already done mem_cgroup_get(mc.to) */ | |
483c30b5 DN |
5429 | mc.moved_swap = 0; |
5430 | } | |
dfe076b0 DN |
5431 | memcg_oom_recover(from); |
5432 | memcg_oom_recover(to); | |
5433 | wake_up_all(&mc.waitq); | |
5434 | } | |
5435 | ||
5436 | static void mem_cgroup_clear_mc(void) | |
5437 | { | |
5438 | struct mem_cgroup *from = mc.from; | |
5439 | ||
5440 | /* | |
5441 | * we must clear moving_task before waking up waiters at the end of | |
5442 | * task migration. | |
5443 | */ | |
5444 | mc.moving_task = NULL; | |
5445 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 5446 | spin_lock(&mc.lock); |
4ffef5fe DN |
5447 | mc.from = NULL; |
5448 | mc.to = NULL; | |
2bd9bb20 | 5449 | spin_unlock(&mc.lock); |
32047e2a | 5450 | mem_cgroup_end_move(from); |
4ffef5fe DN |
5451 | } |
5452 | ||
7dc74be0 DN |
5453 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, |
5454 | struct cgroup *cgroup, | |
f780bdb7 | 5455 | struct task_struct *p) |
7dc74be0 DN |
5456 | { |
5457 | int ret = 0; | |
5458 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgroup); | |
5459 | ||
5460 | if (mem->move_charge_at_immigrate) { | |
5461 | struct mm_struct *mm; | |
5462 | struct mem_cgroup *from = mem_cgroup_from_task(p); | |
5463 | ||
5464 | VM_BUG_ON(from == mem); | |
5465 | ||
5466 | mm = get_task_mm(p); | |
5467 | if (!mm) | |
5468 | return 0; | |
7dc74be0 | 5469 | /* We move charges only when we move a owner of the mm */ |
4ffef5fe DN |
5470 | if (mm->owner == p) { |
5471 | VM_BUG_ON(mc.from); | |
5472 | VM_BUG_ON(mc.to); | |
5473 | VM_BUG_ON(mc.precharge); | |
854ffa8d | 5474 | VM_BUG_ON(mc.moved_charge); |
483c30b5 | 5475 | VM_BUG_ON(mc.moved_swap); |
32047e2a | 5476 | mem_cgroup_start_move(from); |
2bd9bb20 | 5477 | spin_lock(&mc.lock); |
4ffef5fe DN |
5478 | mc.from = from; |
5479 | mc.to = mem; | |
2bd9bb20 | 5480 | spin_unlock(&mc.lock); |
dfe076b0 | 5481 | /* We set mc.moving_task later */ |
4ffef5fe DN |
5482 | |
5483 | ret = mem_cgroup_precharge_mc(mm); | |
5484 | if (ret) | |
5485 | mem_cgroup_clear_mc(); | |
dfe076b0 DN |
5486 | } |
5487 | mmput(mm); | |
7dc74be0 DN |
5488 | } |
5489 | return ret; | |
5490 | } | |
5491 | ||
5492 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, | |
5493 | struct cgroup *cgroup, | |
f780bdb7 | 5494 | struct task_struct *p) |
7dc74be0 | 5495 | { |
4ffef5fe | 5496 | mem_cgroup_clear_mc(); |
7dc74be0 DN |
5497 | } |
5498 | ||
4ffef5fe DN |
5499 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
5500 | unsigned long addr, unsigned long end, | |
5501 | struct mm_walk *walk) | |
7dc74be0 | 5502 | { |
4ffef5fe DN |
5503 | int ret = 0; |
5504 | struct vm_area_struct *vma = walk->private; | |
5505 | pte_t *pte; | |
5506 | spinlock_t *ptl; | |
5507 | ||
03319327 | 5508 | split_huge_page_pmd(walk->mm, pmd); |
4ffef5fe DN |
5509 | retry: |
5510 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
5511 | for (; addr != end; addr += PAGE_SIZE) { | |
5512 | pte_t ptent = *(pte++); | |
5513 | union mc_target target; | |
5514 | int type; | |
5515 | struct page *page; | |
5516 | struct page_cgroup *pc; | |
02491447 | 5517 | swp_entry_t ent; |
4ffef5fe DN |
5518 | |
5519 | if (!mc.precharge) | |
5520 | break; | |
5521 | ||
5522 | type = is_target_pte_for_mc(vma, addr, ptent, &target); | |
5523 | switch (type) { | |
5524 | case MC_TARGET_PAGE: | |
5525 | page = target.page; | |
5526 | if (isolate_lru_page(page)) | |
5527 | goto put; | |
5528 | pc = lookup_page_cgroup(page); | |
7ec99d62 JW |
5529 | if (!mem_cgroup_move_account(page, 1, pc, |
5530 | mc.from, mc.to, false)) { | |
4ffef5fe | 5531 | mc.precharge--; |
854ffa8d DN |
5532 | /* we uncharge from mc.from later. */ |
5533 | mc.moved_charge++; | |
4ffef5fe DN |
5534 | } |
5535 | putback_lru_page(page); | |
5536 | put: /* is_target_pte_for_mc() gets the page */ | |
5537 | put_page(page); | |
5538 | break; | |
02491447 DN |
5539 | case MC_TARGET_SWAP: |
5540 | ent = target.ent; | |
483c30b5 DN |
5541 | if (!mem_cgroup_move_swap_account(ent, |
5542 | mc.from, mc.to, false)) { | |
02491447 | 5543 | mc.precharge--; |
483c30b5 DN |
5544 | /* we fixup refcnts and charges later. */ |
5545 | mc.moved_swap++; | |
5546 | } | |
02491447 | 5547 | break; |
4ffef5fe DN |
5548 | default: |
5549 | break; | |
5550 | } | |
5551 | } | |
5552 | pte_unmap_unlock(pte - 1, ptl); | |
5553 | cond_resched(); | |
5554 | ||
5555 | if (addr != end) { | |
5556 | /* | |
5557 | * We have consumed all precharges we got in can_attach(). | |
5558 | * We try charge one by one, but don't do any additional | |
5559 | * charges to mc.to if we have failed in charge once in attach() | |
5560 | * phase. | |
5561 | */ | |
854ffa8d | 5562 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
5563 | if (!ret) |
5564 | goto retry; | |
5565 | } | |
5566 | ||
5567 | return ret; | |
5568 | } | |
5569 | ||
5570 | static void mem_cgroup_move_charge(struct mm_struct *mm) | |
5571 | { | |
5572 | struct vm_area_struct *vma; | |
5573 | ||
5574 | lru_add_drain_all(); | |
dfe076b0 DN |
5575 | retry: |
5576 | if (unlikely(!down_read_trylock(&mm->mmap_sem))) { | |
5577 | /* | |
5578 | * Someone who are holding the mmap_sem might be waiting in | |
5579 | * waitq. So we cancel all extra charges, wake up all waiters, | |
5580 | * and retry. Because we cancel precharges, we might not be able | |
5581 | * to move enough charges, but moving charge is a best-effort | |
5582 | * feature anyway, so it wouldn't be a big problem. | |
5583 | */ | |
5584 | __mem_cgroup_clear_mc(); | |
5585 | cond_resched(); | |
5586 | goto retry; | |
5587 | } | |
4ffef5fe DN |
5588 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5589 | int ret; | |
5590 | struct mm_walk mem_cgroup_move_charge_walk = { | |
5591 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
5592 | .mm = mm, | |
5593 | .private = vma, | |
5594 | }; | |
5595 | if (is_vm_hugetlb_page(vma)) | |
5596 | continue; | |
4ffef5fe DN |
5597 | ret = walk_page_range(vma->vm_start, vma->vm_end, |
5598 | &mem_cgroup_move_charge_walk); | |
5599 | if (ret) | |
5600 | /* | |
5601 | * means we have consumed all precharges and failed in | |
5602 | * doing additional charge. Just abandon here. | |
5603 | */ | |
5604 | break; | |
5605 | } | |
dfe076b0 | 5606 | up_read(&mm->mmap_sem); |
7dc74be0 DN |
5607 | } |
5608 | ||
67e465a7 BS |
5609 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, |
5610 | struct cgroup *cont, | |
5611 | struct cgroup *old_cont, | |
f780bdb7 | 5612 | struct task_struct *p) |
67e465a7 | 5613 | { |
a433658c | 5614 | struct mm_struct *mm = get_task_mm(p); |
dfe076b0 | 5615 | |
dfe076b0 | 5616 | if (mm) { |
a433658c KM |
5617 | if (mc.to) |
5618 | mem_cgroup_move_charge(mm); | |
5619 | put_swap_token(mm); | |
dfe076b0 DN |
5620 | mmput(mm); |
5621 | } | |
a433658c KM |
5622 | if (mc.to) |
5623 | mem_cgroup_clear_mc(); | |
67e465a7 | 5624 | } |
5cfb80a7 DN |
5625 | #else /* !CONFIG_MMU */ |
5626 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, | |
5627 | struct cgroup *cgroup, | |
f780bdb7 | 5628 | struct task_struct *p) |
5cfb80a7 DN |
5629 | { |
5630 | return 0; | |
5631 | } | |
5632 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, | |
5633 | struct cgroup *cgroup, | |
f780bdb7 | 5634 | struct task_struct *p) |
5cfb80a7 DN |
5635 | { |
5636 | } | |
5637 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, | |
5638 | struct cgroup *cont, | |
5639 | struct cgroup *old_cont, | |
f780bdb7 | 5640 | struct task_struct *p) |
5cfb80a7 DN |
5641 | { |
5642 | } | |
5643 | #endif | |
67e465a7 | 5644 | |
8cdea7c0 BS |
5645 | struct cgroup_subsys mem_cgroup_subsys = { |
5646 | .name = "memory", | |
5647 | .subsys_id = mem_cgroup_subsys_id, | |
5648 | .create = mem_cgroup_create, | |
df878fb0 | 5649 | .pre_destroy = mem_cgroup_pre_destroy, |
8cdea7c0 BS |
5650 | .destroy = mem_cgroup_destroy, |
5651 | .populate = mem_cgroup_populate, | |
7dc74be0 DN |
5652 | .can_attach = mem_cgroup_can_attach, |
5653 | .cancel_attach = mem_cgroup_cancel_attach, | |
67e465a7 | 5654 | .attach = mem_cgroup_move_task, |
6d12e2d8 | 5655 | .early_init = 0, |
04046e1a | 5656 | .use_id = 1, |
8cdea7c0 | 5657 | }; |
c077719b KH |
5658 | |
5659 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
a42c390c MH |
5660 | static int __init enable_swap_account(char *s) |
5661 | { | |
5662 | /* consider enabled if no parameter or 1 is given */ | |
a2c8990a | 5663 | if (!strcmp(s, "1")) |
a42c390c | 5664 | really_do_swap_account = 1; |
a2c8990a | 5665 | else if (!strcmp(s, "0")) |
a42c390c MH |
5666 | really_do_swap_account = 0; |
5667 | return 1; | |
5668 | } | |
a2c8990a | 5669 | __setup("swapaccount=", enable_swap_account); |
c077719b | 5670 | |
c077719b | 5671 | #endif |