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Source at commit ec7cab4cbb721bff91ec924ec691efd8daf36579 created 12 years 8 months ago. By Maarten ter Huurne, MIPS: JZ4740: A320: Updated quickstart documentation. | |
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1 | /* memcontrol.c - Memory Controller |
2 | * |
3 | * Copyright IBM Corporation, 2007 |
4 | * Author Balbir Singh <balbir@linux.vnet.ibm.com> |
5 | * |
6 | * Copyright 2007 OpenVZ SWsoft Inc |
7 | * Author: Pavel Emelianov <xemul@openvz.org> |
8 | * |
9 | * Memory thresholds |
10 | * Copyright (C) 2009 Nokia Corporation |
11 | * Author: Kirill A. Shutemov |
12 | * |
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> |
27 | #include <linux/mm.h> |
28 | #include <linux/hugetlb.h> |
29 | #include <linux/pagemap.h> |
30 | #include <linux/smp.h> |
31 | #include <linux/page-flags.h> |
32 | #include <linux/backing-dev.h> |
33 | #include <linux/bit_spinlock.h> |
34 | #include <linux/rcupdate.h> |
35 | #include <linux/limits.h> |
36 | #include <linux/mutex.h> |
37 | #include <linux/rbtree.h> |
38 | #include <linux/slab.h> |
39 | #include <linux/swap.h> |
40 | #include <linux/swapops.h> |
41 | #include <linux/spinlock.h> |
42 | #include <linux/eventfd.h> |
43 | #include <linux/sort.h> |
44 | #include <linux/fs.h> |
45 | #include <linux/seq_file.h> |
46 | #include <linux/vmalloc.h> |
47 | #include <linux/mm_inline.h> |
48 | #include <linux/page_cgroup.h> |
49 | #include <linux/cpu.h> |
50 | #include <linux/oom.h> |
51 | #include "internal.h" |
52 | |
53 | #include <asm/uaccess.h> |
54 | |
55 | #include <trace/events/vmscan.h> |
56 | |
57 | struct cgroup_subsys mem_cgroup_subsys __read_mostly; |
58 | #define MEM_CGROUP_RECLAIM_RETRIES 5 |
59 | struct mem_cgroup *root_mem_cgroup __read_mostly; |
60 | |
61 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
62 | /* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */ |
63 | int do_swap_account __read_mostly; |
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 | |
72 | #else |
73 | #define do_swap_account (0) |
74 | #endif |
75 | |
76 | |
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 */ |
85 | MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */ |
86 | MEM_CGROUP_STAT_FILE_MAPPED, /* # of pages charged as file rss */ |
87 | MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */ |
88 | MEM_CGROUP_STAT_DATA, /* end of data requires synchronization */ |
89 | MEM_CGROUP_ON_MOVE, /* someone is moving account between groups */ |
90 | MEM_CGROUP_STAT_NSTATS, |
91 | }; |
92 | |
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 */ |
97 | MEM_CGROUP_EVENTS_NSTATS, |
98 | }; |
99 | /* |
100 | * Per memcg event counter is incremented at every pagein/pageout. With THP, |
101 | * it will be incremated by the number of pages. This counter is used for |
102 | * for trigger some periodic events. This is straightforward and better |
103 | * than using jiffies etc. to handle periodic memcg event. |
104 | */ |
105 | enum mem_cgroup_events_target { |
106 | MEM_CGROUP_TARGET_THRESH, |
107 | MEM_CGROUP_TARGET_SOFTLIMIT, |
108 | MEM_CGROUP_NTARGETS, |
109 | }; |
110 | #define THRESHOLDS_EVENTS_TARGET (128) |
111 | #define SOFTLIMIT_EVENTS_TARGET (1024) |
112 | |
113 | struct mem_cgroup_stat_cpu { |
114 | long count[MEM_CGROUP_STAT_NSTATS]; |
115 | unsigned long events[MEM_CGROUP_EVENTS_NSTATS]; |
116 | unsigned long targets[MEM_CGROUP_NTARGETS]; |
117 | }; |
118 | |
119 | /* |
120 | * per-zone information in memory controller. |
121 | */ |
122 | struct mem_cgroup_per_zone { |
123 | /* |
124 | * spin_lock to protect the per cgroup LRU |
125 | */ |
126 | struct list_head lists[NR_LRU_LISTS]; |
127 | unsigned long count[NR_LRU_LISTS]; |
128 | |
129 | struct zone_reclaim_stat reclaim_stat; |
130 | struct rb_node tree_node; /* RB tree node */ |
131 | unsigned long long usage_in_excess;/* Set to the value by which */ |
132 | /* the soft limit is exceeded*/ |
133 | bool on_tree; |
134 | struct mem_cgroup *mem; /* Back pointer, we cannot */ |
135 | /* use container_of */ |
136 | }; |
137 | /* Macro for accessing counter */ |
138 | #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)]) |
139 | |
140 | struct mem_cgroup_per_node { |
141 | struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES]; |
142 | }; |
143 | |
144 | struct mem_cgroup_lru_info { |
145 | struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES]; |
146 | }; |
147 | |
148 | /* |
149 | * Cgroups above their limits are maintained in a RB-Tree, independent of |
150 | * their hierarchy representation |
151 | */ |
152 | |
153 | struct mem_cgroup_tree_per_zone { |
154 | struct rb_root rb_root; |
155 | spinlock_t lock; |
156 | }; |
157 | |
158 | struct mem_cgroup_tree_per_node { |
159 | struct mem_cgroup_tree_per_zone rb_tree_per_zone[MAX_NR_ZONES]; |
160 | }; |
161 | |
162 | struct mem_cgroup_tree { |
163 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; |
164 | }; |
165 | |
166 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; |
167 | |
168 | struct mem_cgroup_threshold { |
169 | struct eventfd_ctx *eventfd; |
170 | u64 threshold; |
171 | }; |
172 | |
173 | /* For threshold */ |
174 | struct mem_cgroup_threshold_ary { |
175 | /* An array index points to threshold just below usage. */ |
176 | int current_threshold; |
177 | /* Size of entries[] */ |
178 | unsigned int size; |
179 | /* Array of thresholds */ |
180 | struct mem_cgroup_threshold entries[0]; |
181 | }; |
182 | |
183 | struct mem_cgroup_thresholds { |
184 | /* Primary thresholds array */ |
185 | struct mem_cgroup_threshold_ary *primary; |
186 | /* |
187 | * Spare threshold array. |
188 | * This is needed to make mem_cgroup_unregister_event() "never fail". |
189 | * It must be able to store at least primary->size - 1 entries. |
190 | */ |
191 | struct mem_cgroup_threshold_ary *spare; |
192 | }; |
193 | |
194 | /* for OOM */ |
195 | struct mem_cgroup_eventfd_list { |
196 | struct list_head list; |
197 | struct eventfd_ctx *eventfd; |
198 | }; |
199 | |
200 | static void mem_cgroup_threshold(struct mem_cgroup *mem); |
201 | static void mem_cgroup_oom_notify(struct mem_cgroup *mem); |
202 | |
203 | /* |
204 | * The memory controller data structure. The memory controller controls both |
205 | * page cache and RSS per cgroup. We would eventually like to provide |
206 | * statistics based on the statistics developed by Rik Van Riel for clock-pro, |
207 | * to help the administrator determine what knobs to tune. |
208 | * |
209 | * TODO: Add a water mark for the memory controller. Reclaim will begin when |
210 | * we hit the water mark. May be even add a low water mark, such that |
211 | * no reclaim occurs from a cgroup at it's low water mark, this is |
212 | * a feature that will be implemented much later in the future. |
213 | */ |
214 | struct mem_cgroup { |
215 | struct cgroup_subsys_state css; |
216 | /* |
217 | * the counter to account for memory usage |
218 | */ |
219 | struct res_counter res; |
220 | /* |
221 | * the counter to account for mem+swap usage. |
222 | */ |
223 | struct res_counter memsw; |
224 | /* |
225 | * Per cgroup active and inactive list, similar to the |
226 | * per zone LRU lists. |
227 | */ |
228 | struct mem_cgroup_lru_info info; |
229 | /* |
230 | * While reclaiming in a hierarchy, we cache the last child we |
231 | * reclaimed from. |
232 | */ |
233 | int last_scanned_child; |
234 | /* |
235 | * Should the accounting and control be hierarchical, per subtree? |
236 | */ |
237 | bool use_hierarchy; |
238 | atomic_t oom_lock; |
239 | atomic_t refcnt; |
240 | |
241 | unsigned int swappiness; |
242 | /* OOM-Killer disable */ |
243 | int oom_kill_disable; |
244 | |
245 | /* set when res.limit == memsw.limit */ |
246 | bool memsw_is_minimum; |
247 | |
248 | /* protect arrays of thresholds */ |
249 | struct mutex thresholds_lock; |
250 | |
251 | /* thresholds for memory usage. RCU-protected */ |
252 | struct mem_cgroup_thresholds thresholds; |
253 | |
254 | /* thresholds for mem+swap usage. RCU-protected */ |
255 | struct mem_cgroup_thresholds memsw_thresholds; |
256 | |
257 | /* For oom notifier event fd */ |
258 | struct list_head oom_notify; |
259 | |
260 | /* |
261 | * Should we move charges of a task when a task is moved into this |
262 | * mem_cgroup ? And what type of charges should we move ? |
263 | */ |
264 | unsigned long move_charge_at_immigrate; |
265 | /* |
266 | * percpu counter. |
267 | */ |
268 | struct mem_cgroup_stat_cpu *stat; |
269 | /* |
270 | * used when a cpu is offlined or other synchronizations |
271 | * See mem_cgroup_read_stat(). |
272 | */ |
273 | struct mem_cgroup_stat_cpu nocpu_base; |
274 | spinlock_t pcp_counter_lock; |
275 | }; |
276 | |
277 | /* Stuffs for move charges at task migration. */ |
278 | /* |
279 | * Types of charges to be moved. "move_charge_at_immitgrate" is treated as a |
280 | * left-shifted bitmap of these types. |
281 | */ |
282 | enum move_type { |
283 | MOVE_CHARGE_TYPE_ANON, /* private anonymous page and swap of it */ |
284 | MOVE_CHARGE_TYPE_FILE, /* file page(including tmpfs) and swap of it */ |
285 | NR_MOVE_TYPE, |
286 | }; |
287 | |
288 | /* "mc" and its members are protected by cgroup_mutex */ |
289 | static struct move_charge_struct { |
290 | spinlock_t lock; /* for from, to */ |
291 | struct mem_cgroup *from; |
292 | struct mem_cgroup *to; |
293 | unsigned long precharge; |
294 | unsigned long moved_charge; |
295 | unsigned long moved_swap; |
296 | struct task_struct *moving_task; /* a task moving charges */ |
297 | wait_queue_head_t waitq; /* a waitq for other context */ |
298 | } mc = { |
299 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
300 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
301 | }; |
302 | |
303 | static bool move_anon(void) |
304 | { |
305 | return test_bit(MOVE_CHARGE_TYPE_ANON, |
306 | &mc.to->move_charge_at_immigrate); |
307 | } |
308 | |
309 | static bool move_file(void) |
310 | { |
311 | return test_bit(MOVE_CHARGE_TYPE_FILE, |
312 | &mc.to->move_charge_at_immigrate); |
313 | } |
314 | |
315 | /* |
316 | * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft |
317 | * limit reclaim to prevent infinite loops, if they ever occur. |
318 | */ |
319 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS (100) |
320 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS (2) |
321 | |
322 | enum charge_type { |
323 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, |
324 | MEM_CGROUP_CHARGE_TYPE_MAPPED, |
325 | MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ |
326 | MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ |
327 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
328 | MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ |
329 | NR_CHARGE_TYPE, |
330 | }; |
331 | |
332 | /* for encoding cft->private value on file */ |
333 | #define _MEM (0) |
334 | #define _MEMSWAP (1) |
335 | #define _OOM_TYPE (2) |
336 | #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val)) |
337 | #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff) |
338 | #define MEMFILE_ATTR(val) ((val) & 0xffff) |
339 | /* Used for OOM nofiier */ |
340 | #define OOM_CONTROL (0) |
341 | |
342 | /* |
343 | * Reclaim flags for mem_cgroup_hierarchical_reclaim |
344 | */ |
345 | #define MEM_CGROUP_RECLAIM_NOSWAP_BIT 0x0 |
346 | #define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT) |
347 | #define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1 |
348 | #define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT) |
349 | #define MEM_CGROUP_RECLAIM_SOFT_BIT 0x2 |
350 | #define MEM_CGROUP_RECLAIM_SOFT (1 << MEM_CGROUP_RECLAIM_SOFT_BIT) |
351 | |
352 | static void mem_cgroup_get(struct mem_cgroup *mem); |
353 | static void mem_cgroup_put(struct mem_cgroup *mem); |
354 | static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem); |
355 | static void drain_all_stock_async(void); |
356 | |
357 | static struct mem_cgroup_per_zone * |
358 | mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid) |
359 | { |
360 | return &mem->info.nodeinfo[nid]->zoneinfo[zid]; |
361 | } |
362 | |
363 | struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *mem) |
364 | { |
365 | return &mem->css; |
366 | } |
367 | |
368 | static struct mem_cgroup_per_zone * |
369 | page_cgroup_zoneinfo(struct mem_cgroup *mem, struct page *page) |
370 | { |
371 | int nid = page_to_nid(page); |
372 | int zid = page_zonenum(page); |
373 | |
374 | return mem_cgroup_zoneinfo(mem, nid, zid); |
375 | } |
376 | |
377 | static struct mem_cgroup_tree_per_zone * |
378 | soft_limit_tree_node_zone(int nid, int zid) |
379 | { |
380 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; |
381 | } |
382 | |
383 | static struct mem_cgroup_tree_per_zone * |
384 | soft_limit_tree_from_page(struct page *page) |
385 | { |
386 | int nid = page_to_nid(page); |
387 | int zid = page_zonenum(page); |
388 | |
389 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; |
390 | } |
391 | |
392 | static void |
393 | __mem_cgroup_insert_exceeded(struct mem_cgroup *mem, |
394 | struct mem_cgroup_per_zone *mz, |
395 | struct mem_cgroup_tree_per_zone *mctz, |
396 | unsigned long long new_usage_in_excess) |
397 | { |
398 | struct rb_node **p = &mctz->rb_root.rb_node; |
399 | struct rb_node *parent = NULL; |
400 | struct mem_cgroup_per_zone *mz_node; |
401 | |
402 | if (mz->on_tree) |
403 | return; |
404 | |
405 | mz->usage_in_excess = new_usage_in_excess; |
406 | if (!mz->usage_in_excess) |
407 | return; |
408 | while (*p) { |
409 | parent = *p; |
410 | mz_node = rb_entry(parent, struct mem_cgroup_per_zone, |
411 | tree_node); |
412 | if (mz->usage_in_excess < mz_node->usage_in_excess) |
413 | p = &(*p)->rb_left; |
414 | /* |
415 | * We can't avoid mem cgroups that are over their soft |
416 | * limit by the same amount |
417 | */ |
418 | else if (mz->usage_in_excess >= mz_node->usage_in_excess) |
419 | p = &(*p)->rb_right; |
420 | } |
421 | rb_link_node(&mz->tree_node, parent, p); |
422 | rb_insert_color(&mz->tree_node, &mctz->rb_root); |
423 | mz->on_tree = true; |
424 | } |
425 | |
426 | static void |
427 | __mem_cgroup_remove_exceeded(struct mem_cgroup *mem, |
428 | struct mem_cgroup_per_zone *mz, |
429 | struct mem_cgroup_tree_per_zone *mctz) |
430 | { |
431 | if (!mz->on_tree) |
432 | return; |
433 | rb_erase(&mz->tree_node, &mctz->rb_root); |
434 | mz->on_tree = false; |
435 | } |
436 | |
437 | static void |
438 | mem_cgroup_remove_exceeded(struct mem_cgroup *mem, |
439 | struct mem_cgroup_per_zone *mz, |
440 | struct mem_cgroup_tree_per_zone *mctz) |
441 | { |
442 | spin_lock(&mctz->lock); |
443 | __mem_cgroup_remove_exceeded(mem, mz, mctz); |
444 | spin_unlock(&mctz->lock); |
445 | } |
446 | |
447 | |
448 | static void mem_cgroup_update_tree(struct mem_cgroup *mem, struct page *page) |
449 | { |
450 | unsigned long long excess; |
451 | struct mem_cgroup_per_zone *mz; |
452 | struct mem_cgroup_tree_per_zone *mctz; |
453 | int nid = page_to_nid(page); |
454 | int zid = page_zonenum(page); |
455 | mctz = soft_limit_tree_from_page(page); |
456 | |
457 | /* |
458 | * Necessary to update all ancestors when hierarchy is used. |
459 | * because their event counter is not touched. |
460 | */ |
461 | for (; mem; mem = parent_mem_cgroup(mem)) { |
462 | mz = mem_cgroup_zoneinfo(mem, nid, zid); |
463 | excess = res_counter_soft_limit_excess(&mem->res); |
464 | /* |
465 | * We have to update the tree if mz is on RB-tree or |
466 | * mem is over its softlimit. |
467 | */ |
468 | if (excess || mz->on_tree) { |
469 | spin_lock(&mctz->lock); |
470 | /* if on-tree, remove it */ |
471 | if (mz->on_tree) |
472 | __mem_cgroup_remove_exceeded(mem, mz, mctz); |
473 | /* |
474 | * Insert again. mz->usage_in_excess will be updated. |
475 | * If excess is 0, no tree ops. |
476 | */ |
477 | __mem_cgroup_insert_exceeded(mem, mz, mctz, excess); |
478 | spin_unlock(&mctz->lock); |
479 | } |
480 | } |
481 | } |
482 | |
483 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *mem) |
484 | { |
485 | int node, zone; |
486 | struct mem_cgroup_per_zone *mz; |
487 | struct mem_cgroup_tree_per_zone *mctz; |
488 | |
489 | for_each_node_state(node, N_POSSIBLE) { |
490 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
491 | mz = mem_cgroup_zoneinfo(mem, node, zone); |
492 | mctz = soft_limit_tree_node_zone(node, zone); |
493 | mem_cgroup_remove_exceeded(mem, mz, mctz); |
494 | } |
495 | } |
496 | } |
497 | |
498 | static struct mem_cgroup_per_zone * |
499 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) |
500 | { |
501 | struct rb_node *rightmost = NULL; |
502 | struct mem_cgroup_per_zone *mz; |
503 | |
504 | retry: |
505 | mz = NULL; |
506 | rightmost = rb_last(&mctz->rb_root); |
507 | if (!rightmost) |
508 | goto done; /* Nothing to reclaim from */ |
509 | |
510 | mz = rb_entry(rightmost, struct mem_cgroup_per_zone, tree_node); |
511 | /* |
512 | * Remove the node now but someone else can add it back, |
513 | * we will to add it back at the end of reclaim to its correct |
514 | * position in the tree. |
515 | */ |
516 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); |
517 | if (!res_counter_soft_limit_excess(&mz->mem->res) || |
518 | !css_tryget(&mz->mem->css)) |
519 | goto retry; |
520 | done: |
521 | return mz; |
522 | } |
523 | |
524 | static struct mem_cgroup_per_zone * |
525 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) |
526 | { |
527 | struct mem_cgroup_per_zone *mz; |
528 | |
529 | spin_lock(&mctz->lock); |
530 | mz = __mem_cgroup_largest_soft_limit_node(mctz); |
531 | spin_unlock(&mctz->lock); |
532 | return mz; |
533 | } |
534 | |
535 | /* |
536 | * Implementation Note: reading percpu statistics for memcg. |
537 | * |
538 | * Both of vmstat[] and percpu_counter has threshold and do periodic |
539 | * synchronization to implement "quick" read. There are trade-off between |
540 | * reading cost and precision of value. Then, we may have a chance to implement |
541 | * a periodic synchronizion of counter in memcg's counter. |
542 | * |
543 | * But this _read() function is used for user interface now. The user accounts |
544 | * memory usage by memory cgroup and he _always_ requires exact value because |
545 | * he accounts memory. Even if we provide quick-and-fuzzy read, we always |
546 | * have to visit all online cpus and make sum. So, for now, unnecessary |
547 | * synchronization is not implemented. (just implemented for cpu hotplug) |
548 | * |
549 | * If there are kernel internal actions which can make use of some not-exact |
550 | * value, and reading all cpu value can be performance bottleneck in some |
551 | * common workload, threashold and synchonization as vmstat[] should be |
552 | * implemented. |
553 | */ |
554 | static long mem_cgroup_read_stat(struct mem_cgroup *mem, |
555 | enum mem_cgroup_stat_index idx) |
556 | { |
557 | long val = 0; |
558 | int cpu; |
559 | |
560 | get_online_cpus(); |
561 | for_each_online_cpu(cpu) |
562 | val += per_cpu(mem->stat->count[idx], cpu); |
563 | #ifdef CONFIG_HOTPLUG_CPU |
564 | spin_lock(&mem->pcp_counter_lock); |
565 | val += mem->nocpu_base.count[idx]; |
566 | spin_unlock(&mem->pcp_counter_lock); |
567 | #endif |
568 | put_online_cpus(); |
569 | return val; |
570 | } |
571 | |
572 | static long mem_cgroup_local_usage(struct mem_cgroup *mem) |
573 | { |
574 | long ret; |
575 | |
576 | ret = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_RSS); |
577 | ret += mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_CACHE); |
578 | return ret; |
579 | } |
580 | |
581 | static void mem_cgroup_swap_statistics(struct mem_cgroup *mem, |
582 | bool charge) |
583 | { |
584 | int val = (charge) ? 1 : -1; |
585 | this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_SWAPOUT], val); |
586 | } |
587 | |
588 | static unsigned long mem_cgroup_read_events(struct mem_cgroup *mem, |
589 | enum mem_cgroup_events_index idx) |
590 | { |
591 | unsigned long val = 0; |
592 | int cpu; |
593 | |
594 | for_each_online_cpu(cpu) |
595 | val += per_cpu(mem->stat->events[idx], cpu); |
596 | #ifdef CONFIG_HOTPLUG_CPU |
597 | spin_lock(&mem->pcp_counter_lock); |
598 | val += mem->nocpu_base.events[idx]; |
599 | spin_unlock(&mem->pcp_counter_lock); |
600 | #endif |
601 | return val; |
602 | } |
603 | |
604 | static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, |
605 | bool file, int nr_pages) |
606 | { |
607 | preempt_disable(); |
608 | |
609 | if (file) |
610 | __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_CACHE], nr_pages); |
611 | else |
612 | __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_RSS], nr_pages); |
613 | |
614 | /* pagein of a big page is an event. So, ignore page size */ |
615 | if (nr_pages > 0) |
616 | __this_cpu_inc(mem->stat->events[MEM_CGROUP_EVENTS_PGPGIN]); |
617 | else { |
618 | __this_cpu_inc(mem->stat->events[MEM_CGROUP_EVENTS_PGPGOUT]); |
619 | nr_pages = -nr_pages; /* for event */ |
620 | } |
621 | |
622 | __this_cpu_add(mem->stat->events[MEM_CGROUP_EVENTS_COUNT], nr_pages); |
623 | |
624 | preempt_enable(); |
625 | } |
626 | |
627 | static unsigned long mem_cgroup_get_local_zonestat(struct mem_cgroup *mem, |
628 | enum lru_list idx) |
629 | { |
630 | int nid, zid; |
631 | struct mem_cgroup_per_zone *mz; |
632 | u64 total = 0; |
633 | |
634 | for_each_online_node(nid) |
635 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { |
636 | mz = mem_cgroup_zoneinfo(mem, nid, zid); |
637 | total += MEM_CGROUP_ZSTAT(mz, idx); |
638 | } |
639 | return total; |
640 | } |
641 | |
642 | static bool __memcg_event_check(struct mem_cgroup *mem, int target) |
643 | { |
644 | unsigned long val, next; |
645 | |
646 | val = this_cpu_read(mem->stat->events[MEM_CGROUP_EVENTS_COUNT]); |
647 | next = this_cpu_read(mem->stat->targets[target]); |
648 | /* from time_after() in jiffies.h */ |
649 | return ((long)next - (long)val < 0); |
650 | } |
651 | |
652 | static void __mem_cgroup_target_update(struct mem_cgroup *mem, int target) |
653 | { |
654 | unsigned long val, next; |
655 | |
656 | val = this_cpu_read(mem->stat->events[MEM_CGROUP_EVENTS_COUNT]); |
657 | |
658 | switch (target) { |
659 | case MEM_CGROUP_TARGET_THRESH: |
660 | next = val + THRESHOLDS_EVENTS_TARGET; |
661 | break; |
662 | case MEM_CGROUP_TARGET_SOFTLIMIT: |
663 | next = val + SOFTLIMIT_EVENTS_TARGET; |
664 | break; |
665 | default: |
666 | return; |
667 | } |
668 | |
669 | this_cpu_write(mem->stat->targets[target], next); |
670 | } |
671 | |
672 | /* |
673 | * Check events in order. |
674 | * |
675 | */ |
676 | static void memcg_check_events(struct mem_cgroup *mem, struct page *page) |
677 | { |
678 | /* threshold event is triggered in finer grain than soft limit */ |
679 | if (unlikely(__memcg_event_check(mem, MEM_CGROUP_TARGET_THRESH))) { |
680 | mem_cgroup_threshold(mem); |
681 | __mem_cgroup_target_update(mem, MEM_CGROUP_TARGET_THRESH); |
682 | if (unlikely(__memcg_event_check(mem, |
683 | MEM_CGROUP_TARGET_SOFTLIMIT))){ |
684 | mem_cgroup_update_tree(mem, page); |
685 | __mem_cgroup_target_update(mem, |
686 | MEM_CGROUP_TARGET_SOFTLIMIT); |
687 | } |
688 | } |
689 | } |
690 | |
691 | static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) |
692 | { |
693 | return container_of(cgroup_subsys_state(cont, |
694 | mem_cgroup_subsys_id), struct mem_cgroup, |
695 | css); |
696 | } |
697 | |
698 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
699 | { |
700 | /* |
701 | * mm_update_next_owner() may clear mm->owner to NULL |
702 | * if it races with swapoff, page migration, etc. |
703 | * So this can be called with p == NULL. |
704 | */ |
705 | if (unlikely(!p)) |
706 | return NULL; |
707 | |
708 | return container_of(task_subsys_state(p, mem_cgroup_subsys_id), |
709 | struct mem_cgroup, css); |
710 | } |
711 | |
712 | static struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) |
713 | { |
714 | struct mem_cgroup *mem = NULL; |
715 | |
716 | if (!mm) |
717 | return NULL; |
718 | /* |
719 | * Because we have no locks, mm->owner's may be being moved to other |
720 | * cgroup. We use css_tryget() here even if this looks |
721 | * pessimistic (rather than adding locks here). |
722 | */ |
723 | rcu_read_lock(); |
724 | do { |
725 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); |
726 | if (unlikely(!mem)) |
727 | break; |
728 | } while (!css_tryget(&mem->css)); |
729 | rcu_read_unlock(); |
730 | return mem; |
731 | } |
732 | |
733 | /* The caller has to guarantee "mem" exists before calling this */ |
734 | static struct mem_cgroup *mem_cgroup_start_loop(struct mem_cgroup *mem) |
735 | { |
736 | struct cgroup_subsys_state *css; |
737 | int found; |
738 | |
739 | if (!mem) /* ROOT cgroup has the smallest ID */ |
740 | return root_mem_cgroup; /*css_put/get against root is ignored*/ |
741 | if (!mem->use_hierarchy) { |
742 | if (css_tryget(&mem->css)) |
743 | return mem; |
744 | return NULL; |
745 | } |
746 | rcu_read_lock(); |
747 | /* |
748 | * searching a memory cgroup which has the smallest ID under given |
749 | * ROOT cgroup. (ID >= 1) |
750 | */ |
751 | css = css_get_next(&mem_cgroup_subsys, 1, &mem->css, &found); |
752 | if (css && css_tryget(css)) |
753 | mem = container_of(css, struct mem_cgroup, css); |
754 | else |
755 | mem = NULL; |
756 | rcu_read_unlock(); |
757 | return mem; |
758 | } |
759 | |
760 | static struct mem_cgroup *mem_cgroup_get_next(struct mem_cgroup *iter, |
761 | struct mem_cgroup *root, |
762 | bool cond) |
763 | { |
764 | int nextid = css_id(&iter->css) + 1; |
765 | int found; |
766 | int hierarchy_used; |
767 | struct cgroup_subsys_state *css; |
768 | |
769 | hierarchy_used = iter->use_hierarchy; |
770 | |
771 | css_put(&iter->css); |
772 | /* If no ROOT, walk all, ignore hierarchy */ |
773 | if (!cond || (root && !hierarchy_used)) |
774 | return NULL; |
775 | |
776 | if (!root) |
777 | root = root_mem_cgroup; |
778 | |
779 | do { |
780 | iter = NULL; |
781 | rcu_read_lock(); |
782 | |
783 | css = css_get_next(&mem_cgroup_subsys, nextid, |
784 | &root->css, &found); |
785 | if (css && css_tryget(css)) |
786 | iter = container_of(css, struct mem_cgroup, css); |
787 | rcu_read_unlock(); |
788 | /* If css is NULL, no more cgroups will be found */ |
789 | nextid = found + 1; |
790 | } while (css && !iter); |
791 | |
792 | return iter; |
793 | } |
794 | /* |
795 | * for_eacn_mem_cgroup_tree() for visiting all cgroup under tree. Please |
796 | * be careful that "break" loop is not allowed. We have reference count. |
797 | * Instead of that modify "cond" to be false and "continue" to exit the loop. |
798 | */ |
799 | #define for_each_mem_cgroup_tree_cond(iter, root, cond) \ |
800 | for (iter = mem_cgroup_start_loop(root);\ |
801 | iter != NULL;\ |
802 | iter = mem_cgroup_get_next(iter, root, cond)) |
803 | |
804 | #define for_each_mem_cgroup_tree(iter, root) \ |
805 | for_each_mem_cgroup_tree_cond(iter, root, true) |
806 | |
807 | #define for_each_mem_cgroup_all(iter) \ |
808 | for_each_mem_cgroup_tree_cond(iter, NULL, true) |
809 | |
810 | |
811 | static inline bool mem_cgroup_is_root(struct mem_cgroup *mem) |
812 | { |
813 | return (mem == root_mem_cgroup); |
814 | } |
815 | |
816 | /* |
817 | * Following LRU functions are allowed to be used without PCG_LOCK. |
818 | * Operations are called by routine of global LRU independently from memcg. |
819 | * What we have to take care of here is validness of pc->mem_cgroup. |
820 | * |
821 | * Changes to pc->mem_cgroup happens when |
822 | * 1. charge |
823 | * 2. moving account |
824 | * In typical case, "charge" is done before add-to-lru. Exception is SwapCache. |
825 | * It is added to LRU before charge. |
826 | * If PCG_USED bit is not set, page_cgroup is not added to this private LRU. |
827 | * When moving account, the page is not on LRU. It's isolated. |
828 | */ |
829 | |
830 | void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru) |
831 | { |
832 | struct page_cgroup *pc; |
833 | struct mem_cgroup_per_zone *mz; |
834 | |
835 | if (mem_cgroup_disabled()) |
836 | return; |
837 | pc = lookup_page_cgroup(page); |
838 | /* can happen while we handle swapcache. */ |
839 | if (!TestClearPageCgroupAcctLRU(pc)) |
840 | return; |
841 | VM_BUG_ON(!pc->mem_cgroup); |
842 | /* |
843 | * We don't check PCG_USED bit. It's cleared when the "page" is finally |
844 | * removed from global LRU. |
845 | */ |
846 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
847 | /* huge page split is done under lru_lock. so, we have no races. */ |
848 | MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page); |
849 | if (mem_cgroup_is_root(pc->mem_cgroup)) |
850 | return; |
851 | VM_BUG_ON(list_empty(&pc->lru)); |
852 | list_del_init(&pc->lru); |
853 | } |
854 | |
855 | void mem_cgroup_del_lru(struct page *page) |
856 | { |
857 | mem_cgroup_del_lru_list(page, page_lru(page)); |
858 | } |
859 | |
860 | /* |
861 | * Writeback is about to end against a page which has been marked for immediate |
862 | * reclaim. If it still appears to be reclaimable, move it to the tail of the |
863 | * inactive list. |
864 | */ |
865 | void mem_cgroup_rotate_reclaimable_page(struct page *page) |
866 | { |
867 | struct mem_cgroup_per_zone *mz; |
868 | struct page_cgroup *pc; |
869 | enum lru_list lru = page_lru(page); |
870 | |
871 | if (mem_cgroup_disabled()) |
872 | return; |
873 | |
874 | pc = lookup_page_cgroup(page); |
875 | /* unused or root page is not rotated. */ |
876 | if (!PageCgroupUsed(pc)) |
877 | return; |
878 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
879 | smp_rmb(); |
880 | if (mem_cgroup_is_root(pc->mem_cgroup)) |
881 | return; |
882 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
883 | list_move_tail(&pc->lru, &mz->lists[lru]); |
884 | } |
885 | |
886 | void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru) |
887 | { |
888 | struct mem_cgroup_per_zone *mz; |
889 | struct page_cgroup *pc; |
890 | |
891 | if (mem_cgroup_disabled()) |
892 | return; |
893 | |
894 | pc = lookup_page_cgroup(page); |
895 | /* unused or root page is not rotated. */ |
896 | if (!PageCgroupUsed(pc)) |
897 | return; |
898 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
899 | smp_rmb(); |
900 | if (mem_cgroup_is_root(pc->mem_cgroup)) |
901 | return; |
902 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
903 | list_move(&pc->lru, &mz->lists[lru]); |
904 | } |
905 | |
906 | void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru) |
907 | { |
908 | struct page_cgroup *pc; |
909 | struct mem_cgroup_per_zone *mz; |
910 | |
911 | if (mem_cgroup_disabled()) |
912 | return; |
913 | pc = lookup_page_cgroup(page); |
914 | VM_BUG_ON(PageCgroupAcctLRU(pc)); |
915 | if (!PageCgroupUsed(pc)) |
916 | return; |
917 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
918 | smp_rmb(); |
919 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
920 | /* huge page split is done under lru_lock. so, we have no races. */ |
921 | MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page); |
922 | SetPageCgroupAcctLRU(pc); |
923 | if (mem_cgroup_is_root(pc->mem_cgroup)) |
924 | return; |
925 | list_add(&pc->lru, &mz->lists[lru]); |
926 | } |
927 | |
928 | /* |
929 | * At handling SwapCache and other FUSE stuff, pc->mem_cgroup may be changed |
930 | * while it's linked to lru because the page may be reused after it's fully |
931 | * uncharged. To handle that, unlink page_cgroup from LRU when charge it again. |
932 | * It's done under lock_page and expected that zone->lru_lock isnever held. |
933 | */ |
934 | static void mem_cgroup_lru_del_before_commit(struct page *page) |
935 | { |
936 | unsigned long flags; |
937 | struct zone *zone = page_zone(page); |
938 | struct page_cgroup *pc = lookup_page_cgroup(page); |
939 | |
940 | /* |
941 | * Doing this check without taking ->lru_lock seems wrong but this |
942 | * is safe. Because if page_cgroup's USED bit is unset, the page |
943 | * will not be added to any memcg's LRU. If page_cgroup's USED bit is |
944 | * set, the commit after this will fail, anyway. |
945 | * This all charge/uncharge is done under some mutual execustion. |
946 | * So, we don't need to taking care of changes in USED bit. |
947 | */ |
948 | if (likely(!PageLRU(page))) |
949 | return; |
950 | |
951 | spin_lock_irqsave(&zone->lru_lock, flags); |
952 | /* |
953 | * Forget old LRU when this page_cgroup is *not* used. This Used bit |
954 | * is guarded by lock_page() because the page is SwapCache. |
955 | */ |
956 | if (!PageCgroupUsed(pc)) |
957 | mem_cgroup_del_lru_list(page, page_lru(page)); |
958 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
959 | } |
960 | |
961 | static void mem_cgroup_lru_add_after_commit(struct page *page) |
962 | { |
963 | unsigned long flags; |
964 | struct zone *zone = page_zone(page); |
965 | struct page_cgroup *pc = lookup_page_cgroup(page); |
966 | |
967 | /* taking care of that the page is added to LRU while we commit it */ |
968 | if (likely(!PageLRU(page))) |
969 | return; |
970 | spin_lock_irqsave(&zone->lru_lock, flags); |
971 | /* link when the page is linked to LRU but page_cgroup isn't */ |
972 | if (PageLRU(page) && !PageCgroupAcctLRU(pc)) |
973 | mem_cgroup_add_lru_list(page, page_lru(page)); |
974 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
975 | } |
976 | |
977 | |
978 | void mem_cgroup_move_lists(struct page *page, |
979 | enum lru_list from, enum lru_list to) |
980 | { |
981 | if (mem_cgroup_disabled()) |
982 | return; |
983 | mem_cgroup_del_lru_list(page, from); |
984 | mem_cgroup_add_lru_list(page, to); |
985 | } |
986 | |
987 | int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem) |
988 | { |
989 | int ret; |
990 | struct mem_cgroup *curr = NULL; |
991 | struct task_struct *p; |
992 | |
993 | p = find_lock_task_mm(task); |
994 | if (!p) |
995 | return 0; |
996 | curr = try_get_mem_cgroup_from_mm(p->mm); |
997 | task_unlock(p); |
998 | if (!curr) |
999 | return 0; |
1000 | /* |
1001 | * We should check use_hierarchy of "mem" not "curr". Because checking |
1002 | * use_hierarchy of "curr" here make this function true if hierarchy is |
1003 | * enabled in "curr" and "curr" is a child of "mem" in *cgroup* |
1004 | * hierarchy(even if use_hierarchy is disabled in "mem"). |
1005 | */ |
1006 | if (mem->use_hierarchy) |
1007 | ret = css_is_ancestor(&curr->css, &mem->css); |
1008 | else |
1009 | ret = (curr == mem); |
1010 | css_put(&curr->css); |
1011 | return ret; |
1012 | } |
1013 | |
1014 | static int calc_inactive_ratio(struct mem_cgroup *memcg, unsigned long *present_pages) |
1015 | { |
1016 | unsigned long active; |
1017 | unsigned long inactive; |
1018 | unsigned long gb; |
1019 | unsigned long inactive_ratio; |
1020 | |
1021 | inactive = mem_cgroup_get_local_zonestat(memcg, LRU_INACTIVE_ANON); |
1022 | active = mem_cgroup_get_local_zonestat(memcg, LRU_ACTIVE_ANON); |
1023 | |
1024 | gb = (inactive + active) >> (30 - PAGE_SHIFT); |
1025 | if (gb) |
1026 | inactive_ratio = int_sqrt(10 * gb); |
1027 | else |
1028 | inactive_ratio = 1; |
1029 | |
1030 | if (present_pages) { |
1031 | present_pages[0] = inactive; |
1032 | present_pages[1] = active; |
1033 | } |
1034 | |
1035 | return inactive_ratio; |
1036 | } |
1037 | |
1038 | int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg) |
1039 | { |
1040 | unsigned long active; |
1041 | unsigned long inactive; |
1042 | unsigned long present_pages[2]; |
1043 | unsigned long inactive_ratio; |
1044 | |
1045 | inactive_ratio = calc_inactive_ratio(memcg, present_pages); |
1046 | |
1047 | inactive = present_pages[0]; |
1048 | active = present_pages[1]; |
1049 | |
1050 | if (inactive * inactive_ratio < active) |
1051 | return 1; |
1052 | |
1053 | return 0; |
1054 | } |
1055 | |
1056 | int mem_cgroup_inactive_file_is_low(struct mem_cgroup *memcg) |
1057 | { |
1058 | unsigned long active; |
1059 | unsigned long inactive; |
1060 | |
1061 | inactive = mem_cgroup_get_local_zonestat(memcg, LRU_INACTIVE_FILE); |
1062 | active = mem_cgroup_get_local_zonestat(memcg, LRU_ACTIVE_FILE); |
1063 | |
1064 | return (active > inactive); |
1065 | } |
1066 | |
1067 | unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup *memcg, |
1068 | struct zone *zone, |
1069 | enum lru_list lru) |
1070 | { |
1071 | int nid = zone_to_nid(zone); |
1072 | int zid = zone_idx(zone); |
1073 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); |
1074 | |
1075 | return MEM_CGROUP_ZSTAT(mz, lru); |
1076 | } |
1077 | |
1078 | struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg, |
1079 | struct zone *zone) |
1080 | { |
1081 | int nid = zone_to_nid(zone); |
1082 | int zid = zone_idx(zone); |
1083 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); |
1084 | |
1085 | return &mz->reclaim_stat; |
1086 | } |
1087 | |
1088 | struct zone_reclaim_stat * |
1089 | mem_cgroup_get_reclaim_stat_from_page(struct page *page) |
1090 | { |
1091 | struct page_cgroup *pc; |
1092 | struct mem_cgroup_per_zone *mz; |
1093 | |
1094 | if (mem_cgroup_disabled()) |
1095 | return NULL; |
1096 | |
1097 | pc = lookup_page_cgroup(page); |
1098 | if (!PageCgroupUsed(pc)) |
1099 | return NULL; |
1100 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
1101 | smp_rmb(); |
1102 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
1103 | return &mz->reclaim_stat; |
1104 | } |
1105 | |
1106 | unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, |
1107 | struct list_head *dst, |
1108 | unsigned long *scanned, int order, |
1109 | int mode, struct zone *z, |
1110 | struct mem_cgroup *mem_cont, |
1111 | int active, int file) |
1112 | { |
1113 | unsigned long nr_taken = 0; |
1114 | struct page *page; |
1115 | unsigned long scan; |
1116 | LIST_HEAD(pc_list); |
1117 | struct list_head *src; |
1118 | struct page_cgroup *pc, *tmp; |
1119 | int nid = zone_to_nid(z); |
1120 | int zid = zone_idx(z); |
1121 | struct mem_cgroup_per_zone *mz; |
1122 | int lru = LRU_FILE * file + active; |
1123 | int ret; |
1124 | |
1125 | BUG_ON(!mem_cont); |
1126 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); |
1127 | src = &mz->lists[lru]; |
1128 | |
1129 | scan = 0; |
1130 | list_for_each_entry_safe_reverse(pc, tmp, src, lru) { |
1131 | if (scan >= nr_to_scan) |
1132 | break; |
1133 | |
1134 | if (unlikely(!PageCgroupUsed(pc))) |
1135 | continue; |
1136 | |
1137 | page = lookup_cgroup_page(pc); |
1138 | |
1139 | if (unlikely(!PageLRU(page))) |
1140 | continue; |
1141 | |
1142 | scan++; |
1143 | ret = __isolate_lru_page(page, mode, file); |
1144 | switch (ret) { |
1145 | case 0: |
1146 | list_move(&page->lru, dst); |
1147 | mem_cgroup_del_lru(page); |
1148 | nr_taken += hpage_nr_pages(page); |
1149 | break; |
1150 | case -EBUSY: |
1151 | /* we don't affect global LRU but rotate in our LRU */ |
1152 | mem_cgroup_rotate_lru_list(page, page_lru(page)); |
1153 | break; |
1154 | default: |
1155 | break; |
1156 | } |
1157 | } |
1158 | |
1159 | *scanned = scan; |
1160 | |
1161 | trace_mm_vmscan_memcg_isolate(0, nr_to_scan, scan, nr_taken, |
1162 | 0, 0, 0, mode); |
1163 | |
1164 | return nr_taken; |
1165 | } |
1166 | |
1167 | #define mem_cgroup_from_res_counter(counter, member) \ |
1168 | container_of(counter, struct mem_cgroup, member) |
1169 | |
1170 | /** |
1171 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
1172 | * @mem: the memory cgroup |
1173 | * |
1174 | * Returns the maximum amount of memory @mem can be charged with, in |
1175 | * pages. |
1176 | */ |
1177 | static unsigned long mem_cgroup_margin(struct mem_cgroup *mem) |
1178 | { |
1179 | unsigned long long margin; |
1180 | |
1181 | margin = res_counter_margin(&mem->res); |
1182 | if (do_swap_account) |
1183 | margin = min(margin, res_counter_margin(&mem->memsw)); |
1184 | return margin >> PAGE_SHIFT; |
1185 | } |
1186 | |
1187 | static unsigned int get_swappiness(struct mem_cgroup *memcg) |
1188 | { |
1189 | struct cgroup *cgrp = memcg->css.cgroup; |
1190 | |
1191 | /* root ? */ |
1192 | if (cgrp->parent == NULL) |
1193 | return vm_swappiness; |
1194 | |
1195 | return memcg->swappiness; |
1196 | } |
1197 | |
1198 | static void mem_cgroup_start_move(struct mem_cgroup *mem) |
1199 | { |
1200 | int cpu; |
1201 | |
1202 | get_online_cpus(); |
1203 | spin_lock(&mem->pcp_counter_lock); |
1204 | for_each_online_cpu(cpu) |
1205 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) += 1; |
1206 | mem->nocpu_base.count[MEM_CGROUP_ON_MOVE] += 1; |
1207 | spin_unlock(&mem->pcp_counter_lock); |
1208 | put_online_cpus(); |
1209 | |
1210 | synchronize_rcu(); |
1211 | } |
1212 | |
1213 | static void mem_cgroup_end_move(struct mem_cgroup *mem) |
1214 | { |
1215 | int cpu; |
1216 | |
1217 | if (!mem) |
1218 | return; |
1219 | get_online_cpus(); |
1220 | spin_lock(&mem->pcp_counter_lock); |
1221 | for_each_online_cpu(cpu) |
1222 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) -= 1; |
1223 | mem->nocpu_base.count[MEM_CGROUP_ON_MOVE] -= 1; |
1224 | spin_unlock(&mem->pcp_counter_lock); |
1225 | put_online_cpus(); |
1226 | } |
1227 | /* |
1228 | * 2 routines for checking "mem" is under move_account() or not. |
1229 | * |
1230 | * mem_cgroup_stealed() - checking a cgroup is mc.from or not. This is used |
1231 | * for avoiding race in accounting. If true, |
1232 | * pc->mem_cgroup may be overwritten. |
1233 | * |
1234 | * mem_cgroup_under_move() - checking a cgroup is mc.from or mc.to or |
1235 | * under hierarchy of moving cgroups. This is for |
1236 | * waiting at hith-memory prressure caused by "move". |
1237 | */ |
1238 | |
1239 | static bool mem_cgroup_stealed(struct mem_cgroup *mem) |
1240 | { |
1241 | VM_BUG_ON(!rcu_read_lock_held()); |
1242 | return this_cpu_read(mem->stat->count[MEM_CGROUP_ON_MOVE]) > 0; |
1243 | } |
1244 | |
1245 | static bool mem_cgroup_under_move(struct mem_cgroup *mem) |
1246 | { |
1247 | struct mem_cgroup *from; |
1248 | struct mem_cgroup *to; |
1249 | bool ret = false; |
1250 | /* |
1251 | * Unlike task_move routines, we access mc.to, mc.from not under |
1252 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. |
1253 | */ |
1254 | spin_lock(&mc.lock); |
1255 | from = mc.from; |
1256 | to = mc.to; |
1257 | if (!from) |
1258 | goto unlock; |
1259 | if (from == mem || to == mem |
1260 | || (mem->use_hierarchy && css_is_ancestor(&from->css, &mem->css)) |
1261 | || (mem->use_hierarchy && css_is_ancestor(&to->css, &mem->css))) |
1262 | ret = true; |
1263 | unlock: |
1264 | spin_unlock(&mc.lock); |
1265 | return ret; |
1266 | } |
1267 | |
1268 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *mem) |
1269 | { |
1270 | if (mc.moving_task && current != mc.moving_task) { |
1271 | if (mem_cgroup_under_move(mem)) { |
1272 | DEFINE_WAIT(wait); |
1273 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); |
1274 | /* moving charge context might have finished. */ |
1275 | if (mc.moving_task) |
1276 | schedule(); |
1277 | finish_wait(&mc.waitq, &wait); |
1278 | return true; |
1279 | } |
1280 | } |
1281 | return false; |
1282 | } |
1283 | |
1284 | /** |
1285 | * mem_cgroup_print_oom_info: Called from OOM with tasklist_lock held in read mode. |
1286 | * @memcg: The memory cgroup that went over limit |
1287 | * @p: Task that is going to be killed |
1288 | * |
1289 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is |
1290 | * enabled |
1291 | */ |
1292 | void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) |
1293 | { |
1294 | struct cgroup *task_cgrp; |
1295 | struct cgroup *mem_cgrp; |
1296 | /* |
1297 | * Need a buffer in BSS, can't rely on allocations. The code relies |
1298 | * on the assumption that OOM is serialized for memory controller. |
1299 | * If this assumption is broken, revisit this code. |
1300 | */ |
1301 | static char memcg_name[PATH_MAX]; |
1302 | int ret; |
1303 | |
1304 | if (!memcg || !p) |
1305 | return; |
1306 | |
1307 | |
1308 | rcu_read_lock(); |
1309 | |
1310 | mem_cgrp = memcg->css.cgroup; |
1311 | task_cgrp = task_cgroup(p, mem_cgroup_subsys_id); |
1312 | |
1313 | ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX); |
1314 | if (ret < 0) { |
1315 | /* |
1316 | * Unfortunately, we are unable to convert to a useful name |
1317 | * But we'll still print out the usage information |
1318 | */ |
1319 | rcu_read_unlock(); |
1320 | goto done; |
1321 | } |
1322 | rcu_read_unlock(); |
1323 | |
1324 | printk(KERN_INFO "Task in %s killed", memcg_name); |
1325 | |
1326 | rcu_read_lock(); |
1327 | ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX); |
1328 | if (ret < 0) { |
1329 | rcu_read_unlock(); |
1330 | goto done; |
1331 | } |
1332 | rcu_read_unlock(); |
1333 | |
1334 | /* |
1335 | * Continues from above, so we don't need an KERN_ level |
1336 | */ |
1337 | printk(KERN_CONT " as a result of limit of %s\n", memcg_name); |
1338 | done: |
1339 | |
1340 | printk(KERN_INFO "memory: usage %llukB, limit %llukB, failcnt %llu\n", |
1341 | res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, |
1342 | res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, |
1343 | res_counter_read_u64(&memcg->res, RES_FAILCNT)); |
1344 | printk(KERN_INFO "memory+swap: usage %llukB, limit %llukB, " |
1345 | "failcnt %llu\n", |
1346 | res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, |
1347 | res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, |
1348 | res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); |
1349 | } |
1350 | |
1351 | /* |
1352 | * This function returns the number of memcg under hierarchy tree. Returns |
1353 | * 1(self count) if no children. |
1354 | */ |
1355 | static int mem_cgroup_count_children(struct mem_cgroup *mem) |
1356 | { |
1357 | int num = 0; |
1358 | struct mem_cgroup *iter; |
1359 | |
1360 | for_each_mem_cgroup_tree(iter, mem) |
1361 | num++; |
1362 | return num; |
1363 | } |
1364 | |
1365 | /* |
1366 | * Return the memory (and swap, if configured) limit for a memcg. |
1367 | */ |
1368 | u64 mem_cgroup_get_limit(struct mem_cgroup *memcg) |
1369 | { |
1370 | u64 limit; |
1371 | u64 memsw; |
1372 | |
1373 | limit = res_counter_read_u64(&memcg->res, RES_LIMIT); |
1374 | limit += total_swap_pages << PAGE_SHIFT; |
1375 | |
1376 | memsw = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
1377 | /* |
1378 | * If memsw is finite and limits the amount of swap space available |
1379 | * to this memcg, return that limit. |
1380 | */ |
1381 | return min(limit, memsw); |
1382 | } |
1383 | |
1384 | /* |
1385 | * Visit the first child (need not be the first child as per the ordering |
1386 | * of the cgroup list, since we track last_scanned_child) of @mem and use |
1387 | * that to reclaim free pages from. |
1388 | */ |
1389 | static struct mem_cgroup * |
1390 | mem_cgroup_select_victim(struct mem_cgroup *root_mem) |
1391 | { |
1392 | struct mem_cgroup *ret = NULL; |
1393 | struct cgroup_subsys_state *css; |
1394 | int nextid, found; |
1395 | |
1396 | if (!root_mem->use_hierarchy) { |
1397 | css_get(&root_mem->css); |
1398 | ret = root_mem; |
1399 | } |
1400 | |
1401 | while (!ret) { |
1402 | rcu_read_lock(); |
1403 | nextid = root_mem->last_scanned_child + 1; |
1404 | css = css_get_next(&mem_cgroup_subsys, nextid, &root_mem->css, |
1405 | &found); |
1406 | if (css && css_tryget(css)) |
1407 | ret = container_of(css, struct mem_cgroup, css); |
1408 | |
1409 | rcu_read_unlock(); |
1410 | /* Updates scanning parameter */ |
1411 | if (!css) { |
1412 | /* this means start scan from ID:1 */ |
1413 | root_mem->last_scanned_child = 0; |
1414 | } else |
1415 | root_mem->last_scanned_child = found; |
1416 | } |
1417 | |
1418 | return ret; |
1419 | } |
1420 | |
1421 | /* |
1422 | * Scan the hierarchy if needed to reclaim memory. We remember the last child |
1423 | * we reclaimed from, so that we don't end up penalizing one child extensively |
1424 | * based on its position in the children list. |
1425 | * |
1426 | * root_mem is the original ancestor that we've been reclaim from. |
1427 | * |
1428 | * We give up and return to the caller when we visit root_mem twice. |
1429 | * (other groups can be removed while we're walking....) |
1430 | * |
1431 | * If shrink==true, for avoiding to free too much, this returns immedieately. |
1432 | */ |
1433 | static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, |
1434 | struct zone *zone, |
1435 | gfp_t gfp_mask, |
1436 | unsigned long reclaim_options) |
1437 | { |
1438 | struct mem_cgroup *victim; |
1439 | int ret, total = 0; |
1440 | int loop = 0; |
1441 | bool noswap = reclaim_options & MEM_CGROUP_RECLAIM_NOSWAP; |
1442 | bool shrink = reclaim_options & MEM_CGROUP_RECLAIM_SHRINK; |
1443 | bool check_soft = reclaim_options & MEM_CGROUP_RECLAIM_SOFT; |
1444 | unsigned long excess; |
1445 | |
1446 | excess = res_counter_soft_limit_excess(&root_mem->res) >> PAGE_SHIFT; |
1447 | |
1448 | /* If memsw_is_minimum==1, swap-out is of-no-use. */ |
1449 | if (root_mem->memsw_is_minimum) |
1450 | noswap = true; |
1451 | |
1452 | while (1) { |
1453 | victim = mem_cgroup_select_victim(root_mem); |
1454 | if (victim == root_mem) { |
1455 | loop++; |
1456 | if (loop >= 1) |
1457 | drain_all_stock_async(); |
1458 | if (loop >= 2) { |
1459 | /* |
1460 | * If we have not been able to reclaim |
1461 | * anything, it might because there are |
1462 | * no reclaimable pages under this hierarchy |
1463 | */ |
1464 | if (!check_soft || !total) { |
1465 | css_put(&victim->css); |
1466 | break; |
1467 | } |
1468 | /* |
1469 | * We want to do more targeted reclaim. |
1470 | * excess >> 2 is not to excessive so as to |
1471 | * reclaim too much, nor too less that we keep |
1472 | * coming back to reclaim from this cgroup |
1473 | */ |
1474 | if (total >= (excess >> 2) || |
1475 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) { |
1476 | css_put(&victim->css); |
1477 | break; |
1478 | } |
1479 | } |
1480 | } |
1481 | if (!mem_cgroup_local_usage(victim)) { |
1482 | /* this cgroup's local usage == 0 */ |
1483 | css_put(&victim->css); |
1484 | continue; |
1485 | } |
1486 | /* we use swappiness of local cgroup */ |
1487 | if (check_soft) |
1488 | ret = mem_cgroup_shrink_node_zone(victim, gfp_mask, |
1489 | noswap, get_swappiness(victim), zone); |
1490 | else |
1491 | ret = try_to_free_mem_cgroup_pages(victim, gfp_mask, |
1492 | noswap, get_swappiness(victim)); |
1493 | css_put(&victim->css); |
1494 | /* |
1495 | * At shrinking usage, we can't check we should stop here or |
1496 | * reclaim more. It's depends on callers. last_scanned_child |
1497 | * will work enough for keeping fairness under tree. |
1498 | */ |
1499 | if (shrink) |
1500 | return ret; |
1501 | total += ret; |
1502 | if (check_soft) { |
1503 | if (!res_counter_soft_limit_excess(&root_mem->res)) |
1504 | return total; |
1505 | } else if (mem_cgroup_margin(root_mem)) |
1506 | return 1 + total; |
1507 | } |
1508 | return total; |
1509 | } |
1510 | |
1511 | /* |
1512 | * Check OOM-Killer is already running under our hierarchy. |
1513 | * If someone is running, return false. |
1514 | */ |
1515 | static bool mem_cgroup_oom_lock(struct mem_cgroup *mem) |
1516 | { |
1517 | int x, lock_count = 0; |
1518 | struct mem_cgroup *iter; |
1519 | |
1520 | for_each_mem_cgroup_tree(iter, mem) { |
1521 | x = atomic_inc_return(&iter->oom_lock); |
1522 | lock_count = max(x, lock_count); |
1523 | } |
1524 | |
1525 | if (lock_count == 1) |
1526 | return true; |
1527 | return false; |
1528 | } |
1529 | |
1530 | static int mem_cgroup_oom_unlock(struct mem_cgroup *mem) |
1531 | { |
1532 | struct mem_cgroup *iter; |
1533 | |
1534 | /* |
1535 | * When a new child is created while the hierarchy is under oom, |
1536 | * mem_cgroup_oom_lock() may not be called. We have to use |
1537 | * atomic_add_unless() here. |
1538 | */ |
1539 | for_each_mem_cgroup_tree(iter, mem) |
1540 | atomic_add_unless(&iter->oom_lock, -1, 0); |
1541 | return 0; |
1542 | } |
1543 | |
1544 | |
1545 | static DEFINE_MUTEX(memcg_oom_mutex); |
1546 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1547 | |
1548 | struct oom_wait_info { |
1549 | struct mem_cgroup *mem; |
1550 | wait_queue_t wait; |
1551 | }; |
1552 | |
1553 | static int memcg_oom_wake_function(wait_queue_t *wait, |
1554 | unsigned mode, int sync, void *arg) |
1555 | { |
1556 | struct mem_cgroup *wake_mem = (struct mem_cgroup *)arg; |
1557 | struct oom_wait_info *oom_wait_info; |
1558 | |
1559 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); |
1560 | |
1561 | if (oom_wait_info->mem == wake_mem) |
1562 | goto wakeup; |
1563 | /* if no hierarchy, no match */ |
1564 | if (!oom_wait_info->mem->use_hierarchy || !wake_mem->use_hierarchy) |
1565 | return 0; |
1566 | /* |
1567 | * Both of oom_wait_info->mem and wake_mem are stable under us. |
1568 | * Then we can use css_is_ancestor without taking care of RCU. |
1569 | */ |
1570 | if (!css_is_ancestor(&oom_wait_info->mem->css, &wake_mem->css) && |
1571 | !css_is_ancestor(&wake_mem->css, &oom_wait_info->mem->css)) |
1572 | return 0; |
1573 | |
1574 | wakeup: |
1575 | return autoremove_wake_function(wait, mode, sync, arg); |
1576 | } |
1577 | |
1578 | static void memcg_wakeup_oom(struct mem_cgroup *mem) |
1579 | { |
1580 | /* for filtering, pass "mem" as argument. */ |
1581 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, mem); |
1582 | } |
1583 | |
1584 | static void memcg_oom_recover(struct mem_cgroup *mem) |
1585 | { |
1586 | if (mem && atomic_read(&mem->oom_lock)) |
1587 | memcg_wakeup_oom(mem); |
1588 | } |
1589 | |
1590 | /* |
1591 | * try to call OOM killer. returns false if we should exit memory-reclaim loop. |
1592 | */ |
1593 | bool mem_cgroup_handle_oom(struct mem_cgroup *mem, gfp_t mask) |
1594 | { |
1595 | struct oom_wait_info owait; |
1596 | bool locked, need_to_kill; |
1597 | |
1598 | owait.mem = mem; |
1599 | owait.wait.flags = 0; |
1600 | owait.wait.func = memcg_oom_wake_function; |
1601 | owait.wait.private = current; |
1602 | INIT_LIST_HEAD(&owait.wait.task_list); |
1603 | need_to_kill = true; |
1604 | /* At first, try to OOM lock hierarchy under mem.*/ |
1605 | mutex_lock(&memcg_oom_mutex); |
1606 | locked = mem_cgroup_oom_lock(mem); |
1607 | /* |
1608 | * Even if signal_pending(), we can't quit charge() loop without |
1609 | * accounting. So, UNINTERRUPTIBLE is appropriate. But SIGKILL |
1610 | * under OOM is always welcomed, use TASK_KILLABLE here. |
1611 | */ |
1612 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
1613 | if (!locked || mem->oom_kill_disable) |
1614 | need_to_kill = false; |
1615 | if (locked) |
1616 | mem_cgroup_oom_notify(mem); |
1617 | mutex_unlock(&memcg_oom_mutex); |
1618 | |
1619 | if (need_to_kill) { |
1620 | finish_wait(&memcg_oom_waitq, &owait.wait); |
1621 | mem_cgroup_out_of_memory(mem, mask); |
1622 | } else { |
1623 | schedule(); |
1624 | finish_wait(&memcg_oom_waitq, &owait.wait); |
1625 | } |
1626 | mutex_lock(&memcg_oom_mutex); |
1627 | mem_cgroup_oom_unlock(mem); |
1628 | memcg_wakeup_oom(mem); |
1629 | mutex_unlock(&memcg_oom_mutex); |
1630 | |
1631 | if (test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current)) |
1632 | return false; |
1633 | /* Give chance to dying process */ |
1634 | schedule_timeout(1); |
1635 | return true; |
1636 | } |
1637 | |
1638 | /* |
1639 | * Currently used to update mapped file statistics, but the routine can be |
1640 | * generalized to update other statistics as well. |
1641 | * |
1642 | * Notes: Race condition |
1643 | * |
1644 | * We usually use page_cgroup_lock() for accessing page_cgroup member but |
1645 | * it tends to be costly. But considering some conditions, we doesn't need |
1646 | * to do so _always_. |
1647 | * |
1648 | * Considering "charge", lock_page_cgroup() is not required because all |
1649 | * file-stat operations happen after a page is attached to radix-tree. There |
1650 | * are no race with "charge". |
1651 | * |
1652 | * Considering "uncharge", we know that memcg doesn't clear pc->mem_cgroup |
1653 | * at "uncharge" intentionally. So, we always see valid pc->mem_cgroup even |
1654 | * if there are race with "uncharge". Statistics itself is properly handled |
1655 | * by flags. |
1656 | * |
1657 | * Considering "move", this is an only case we see a race. To make the race |
1658 | * small, we check MEM_CGROUP_ON_MOVE percpu value and detect there are |
1659 | * possibility of race condition. If there is, we take a lock. |
1660 | */ |
1661 | |
1662 | void mem_cgroup_update_page_stat(struct page *page, |
1663 | enum mem_cgroup_page_stat_item idx, int val) |
1664 | { |
1665 | struct mem_cgroup *mem; |
1666 | struct page_cgroup *pc = lookup_page_cgroup(page); |
1667 | bool need_unlock = false; |
1668 | unsigned long uninitialized_var(flags); |
1669 | |
1670 | if (unlikely(!pc)) |
1671 | return; |
1672 | |
1673 | rcu_read_lock(); |
1674 | mem = pc->mem_cgroup; |
1675 | if (unlikely(!mem || !PageCgroupUsed(pc))) |
1676 | goto out; |
1677 | /* pc->mem_cgroup is unstable ? */ |
1678 | if (unlikely(mem_cgroup_stealed(mem)) || PageTransHuge(page)) { |
1679 | /* take a lock against to access pc->mem_cgroup */ |
1680 | move_lock_page_cgroup(pc, &flags); |
1681 | need_unlock = true; |
1682 | mem = pc->mem_cgroup; |
1683 | if (!mem || !PageCgroupUsed(pc)) |
1684 | goto out; |
1685 | } |
1686 | |
1687 | switch (idx) { |
1688 | case MEMCG_NR_FILE_MAPPED: |
1689 | if (val > 0) |
1690 | SetPageCgroupFileMapped(pc); |
1691 | else if (!page_mapped(page)) |
1692 | ClearPageCgroupFileMapped(pc); |
1693 | idx = MEM_CGROUP_STAT_FILE_MAPPED; |
1694 | break; |
1695 | default: |
1696 | BUG(); |
1697 | } |
1698 | |
1699 | this_cpu_add(mem->stat->count[idx], val); |
1700 | |
1701 | out: |
1702 | if (unlikely(need_unlock)) |
1703 | move_unlock_page_cgroup(pc, &flags); |
1704 | rcu_read_unlock(); |
1705 | return; |
1706 | } |
1707 | EXPORT_SYMBOL(mem_cgroup_update_page_stat); |
1708 | |
1709 | /* |
1710 | * size of first charge trial. "32" comes from vmscan.c's magic value. |
1711 | * TODO: maybe necessary to use big numbers in big irons. |
1712 | */ |
1713 | #define CHARGE_BATCH 32U |
1714 | struct memcg_stock_pcp { |
1715 | struct mem_cgroup *cached; /* this never be root cgroup */ |
1716 | unsigned int nr_pages; |
1717 | struct work_struct work; |
1718 | }; |
1719 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); |
1720 | static atomic_t memcg_drain_count; |
1721 | |
1722 | /* |
1723 | * Try to consume stocked charge on this cpu. If success, one page is consumed |
1724 | * from local stock and true is returned. If the stock is 0 or charges from a |
1725 | * cgroup which is not current target, returns false. This stock will be |
1726 | * refilled. |
1727 | */ |
1728 | static bool consume_stock(struct mem_cgroup *mem) |
1729 | { |
1730 | struct memcg_stock_pcp *stock; |
1731 | bool ret = true; |
1732 | |
1733 | stock = &get_cpu_var(memcg_stock); |
1734 | if (mem == stock->cached && stock->nr_pages) |
1735 | stock->nr_pages--; |
1736 | else /* need to call res_counter_charge */ |
1737 | ret = false; |
1738 | put_cpu_var(memcg_stock); |
1739 | return ret; |
1740 | } |
1741 | |
1742 | /* |
1743 | * Returns stocks cached in percpu to res_counter and reset cached information. |
1744 | */ |
1745 | static void drain_stock(struct memcg_stock_pcp *stock) |
1746 | { |
1747 | struct mem_cgroup *old = stock->cached; |
1748 | |
1749 | if (stock->nr_pages) { |
1750 | unsigned long bytes = stock->nr_pages * PAGE_SIZE; |
1751 | |
1752 | res_counter_uncharge(&old->res, bytes); |
1753 | if (do_swap_account) |
1754 | res_counter_uncharge(&old->memsw, bytes); |
1755 | stock->nr_pages = 0; |
1756 | } |
1757 | stock->cached = NULL; |
1758 | } |
1759 | |
1760 | /* |
1761 | * This must be called under preempt disabled or must be called by |
1762 | * a thread which is pinned to local cpu. |
1763 | */ |
1764 | static void drain_local_stock(struct work_struct *dummy) |
1765 | { |
1766 | struct memcg_stock_pcp *stock = &__get_cpu_var(memcg_stock); |
1767 | drain_stock(stock); |
1768 | } |
1769 | |
1770 | /* |
1771 | * Cache charges(val) which is from res_counter, to local per_cpu area. |
1772 | * This will be consumed by consume_stock() function, later. |
1773 | */ |
1774 | static void refill_stock(struct mem_cgroup *mem, unsigned int nr_pages) |
1775 | { |
1776 | struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock); |
1777 | |
1778 | if (stock->cached != mem) { /* reset if necessary */ |
1779 | drain_stock(stock); |
1780 | stock->cached = mem; |
1781 | } |
1782 | stock->nr_pages += nr_pages; |
1783 | put_cpu_var(memcg_stock); |
1784 | } |
1785 | |
1786 | /* |
1787 | * Tries to drain stocked charges in other cpus. This function is asynchronous |
1788 | * and just put a work per cpu for draining localy on each cpu. Caller can |
1789 | * expects some charges will be back to res_counter later but cannot wait for |
1790 | * it. |
1791 | */ |
1792 | static void drain_all_stock_async(void) |
1793 | { |
1794 | int cpu; |
1795 | /* This function is for scheduling "drain" in asynchronous way. |
1796 | * The result of "drain" is not directly handled by callers. Then, |
1797 | * if someone is calling drain, we don't have to call drain more. |
1798 | * Anyway, WORK_STRUCT_PENDING check in queue_work_on() will catch if |
1799 | * there is a race. We just do loose check here. |
1800 | */ |
1801 | if (atomic_read(&memcg_drain_count)) |
1802 | return; |
1803 | /* Notify other cpus that system-wide "drain" is running */ |
1804 | atomic_inc(&memcg_drain_count); |
1805 | get_online_cpus(); |
1806 | for_each_online_cpu(cpu) { |
1807 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); |
1808 | schedule_work_on(cpu, &stock->work); |
1809 | } |
1810 | put_online_cpus(); |
1811 | atomic_dec(&memcg_drain_count); |
1812 | /* We don't wait for flush_work */ |
1813 | } |
1814 | |
1815 | /* This is a synchronous drain interface. */ |
1816 | static void drain_all_stock_sync(void) |
1817 | { |
1818 | /* called when force_empty is called */ |
1819 | atomic_inc(&memcg_drain_count); |
1820 | schedule_on_each_cpu(drain_local_stock); |
1821 | atomic_dec(&memcg_drain_count); |
1822 | } |
1823 | |
1824 | /* |
1825 | * This function drains percpu counter value from DEAD cpu and |
1826 | * move it to local cpu. Note that this function can be preempted. |
1827 | */ |
1828 | static void mem_cgroup_drain_pcp_counter(struct mem_cgroup *mem, int cpu) |
1829 | { |
1830 | int i; |
1831 | |
1832 | spin_lock(&mem->pcp_counter_lock); |
1833 | for (i = 0; i < MEM_CGROUP_STAT_DATA; i++) { |
1834 | long x = per_cpu(mem->stat->count[i], cpu); |
1835 | |
1836 | per_cpu(mem->stat->count[i], cpu) = 0; |
1837 | mem->nocpu_base.count[i] += x; |
1838 | } |
1839 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) { |
1840 | unsigned long x = per_cpu(mem->stat->events[i], cpu); |
1841 | |
1842 | per_cpu(mem->stat->events[i], cpu) = 0; |
1843 | mem->nocpu_base.events[i] += x; |
1844 | } |
1845 | /* need to clear ON_MOVE value, works as a kind of lock. */ |
1846 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) = 0; |
1847 | spin_unlock(&mem->pcp_counter_lock); |
1848 | } |
1849 | |
1850 | static void synchronize_mem_cgroup_on_move(struct mem_cgroup *mem, int cpu) |
1851 | { |
1852 | int idx = MEM_CGROUP_ON_MOVE; |
1853 | |
1854 | spin_lock(&mem->pcp_counter_lock); |
1855 | per_cpu(mem->stat->count[idx], cpu) = mem->nocpu_base.count[idx]; |
1856 | spin_unlock(&mem->pcp_counter_lock); |
1857 | } |
1858 | |
1859 | static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, |
1860 | unsigned long action, |
1861 | void *hcpu) |
1862 | { |
1863 | int cpu = (unsigned long)hcpu; |
1864 | struct memcg_stock_pcp *stock; |
1865 | struct mem_cgroup *iter; |
1866 | |
1867 | if ((action == CPU_ONLINE)) { |
1868 | for_each_mem_cgroup_all(iter) |
1869 | synchronize_mem_cgroup_on_move(iter, cpu); |
1870 | return NOTIFY_OK; |
1871 | } |
1872 | |
1873 | if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN) |
1874 | return NOTIFY_OK; |
1875 | |
1876 | for_each_mem_cgroup_all(iter) |
1877 | mem_cgroup_drain_pcp_counter(iter, cpu); |
1878 | |
1879 | stock = &per_cpu(memcg_stock, cpu); |
1880 | drain_stock(stock); |
1881 | return NOTIFY_OK; |
1882 | } |
1883 | |
1884 | |
1885 | /* See __mem_cgroup_try_charge() for details */ |
1886 | enum { |
1887 | CHARGE_OK, /* success */ |
1888 | CHARGE_RETRY, /* need to retry but retry is not bad */ |
1889 | CHARGE_NOMEM, /* we can't do more. return -ENOMEM */ |
1890 | CHARGE_WOULDBLOCK, /* GFP_WAIT wasn't set and no enough res. */ |
1891 | CHARGE_OOM_DIE, /* the current is killed because of OOM */ |
1892 | }; |
1893 | |
1894 | static int mem_cgroup_do_charge(struct mem_cgroup *mem, gfp_t gfp_mask, |
1895 | unsigned int nr_pages, bool oom_check) |
1896 | { |
1897 | unsigned long csize = nr_pages * PAGE_SIZE; |
1898 | struct mem_cgroup *mem_over_limit; |
1899 | struct res_counter *fail_res; |
1900 | unsigned long flags = 0; |
1901 | int ret; |
1902 | |
1903 | ret = res_counter_charge(&mem->res, csize, &fail_res); |
1904 | |
1905 | if (likely(!ret)) { |
1906 | if (!do_swap_account) |
1907 | return CHARGE_OK; |
1908 | ret = res_counter_charge(&mem->memsw, csize, &fail_res); |
1909 | if (likely(!ret)) |
1910 | return CHARGE_OK; |
1911 | |
1912 | res_counter_uncharge(&mem->res, csize); |
1913 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw); |
1914 | flags |= MEM_CGROUP_RECLAIM_NOSWAP; |
1915 | } else |
1916 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, res); |
1917 | /* |
1918 | * nr_pages can be either a huge page (HPAGE_PMD_NR), a batch |
1919 | * of regular pages (CHARGE_BATCH), or a single regular page (1). |
1920 | * |
1921 | * Never reclaim on behalf of optional batching, retry with a |
1922 | * single page instead. |
1923 | */ |
1924 | if (nr_pages == CHARGE_BATCH) |
1925 | return CHARGE_RETRY; |
1926 | |
1927 | if (!(gfp_mask & __GFP_WAIT)) |
1928 | return CHARGE_WOULDBLOCK; |
1929 | |
1930 | ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, NULL, |
1931 | gfp_mask, flags); |
1932 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
1933 | return CHARGE_RETRY; |
1934 | /* |
1935 | * Even though the limit is exceeded at this point, reclaim |
1936 | * may have been able to free some pages. Retry the charge |
1937 | * before killing the task. |
1938 | * |
1939 | * Only for regular pages, though: huge pages are rather |
1940 | * unlikely to succeed so close to the limit, and we fall back |
1941 | * to regular pages anyway in case of failure. |
1942 | */ |
1943 | if (nr_pages == 1 && ret) |
1944 | return CHARGE_RETRY; |
1945 | |
1946 | /* |
1947 | * At task move, charge accounts can be doubly counted. So, it's |
1948 | * better to wait until the end of task_move if something is going on. |
1949 | */ |
1950 | if (mem_cgroup_wait_acct_move(mem_over_limit)) |
1951 | return CHARGE_RETRY; |
1952 | |
1953 | /* If we don't need to call oom-killer at el, return immediately */ |
1954 | if (!oom_check) |
1955 | return CHARGE_NOMEM; |
1956 | /* check OOM */ |
1957 | if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask)) |
1958 | return CHARGE_OOM_DIE; |
1959 | |
1960 | return CHARGE_RETRY; |
1961 | } |
1962 | |
1963 | /* |
1964 | * Unlike exported interface, "oom" parameter is added. if oom==true, |
1965 | * oom-killer can be invoked. |
1966 | */ |
1967 | static int __mem_cgroup_try_charge(struct mm_struct *mm, |
1968 | gfp_t gfp_mask, |
1969 | unsigned int nr_pages, |
1970 | struct mem_cgroup **memcg, |
1971 | bool oom) |
1972 | { |
1973 | unsigned int batch = max(CHARGE_BATCH, nr_pages); |
1974 | int nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; |
1975 | struct mem_cgroup *mem = NULL; |
1976 | int ret; |
1977 | |
1978 | /* |
1979 | * Unlike gloval-vm's OOM-kill, we're not in memory shortage |
1980 | * in system level. So, allow to go ahead dying process in addition to |
1981 | * MEMDIE process. |
1982 | */ |
1983 | if (unlikely(test_thread_flag(TIF_MEMDIE) |
1984 | || fatal_signal_pending(current))) |
1985 | goto bypass; |
1986 | |
1987 | /* |
1988 | * We always charge the cgroup the mm_struct belongs to. |
1989 | * The mm_struct's mem_cgroup changes on task migration if the |
1990 | * thread group leader migrates. It's possible that mm is not |
1991 | * set, if so charge the init_mm (happens for pagecache usage). |
1992 | */ |
1993 | if (!*memcg && !mm) |
1994 | goto bypass; |
1995 | again: |
1996 | if (*memcg) { /* css should be a valid one */ |
1997 | mem = *memcg; |
1998 | VM_BUG_ON(css_is_removed(&mem->css)); |
1999 | if (mem_cgroup_is_root(mem)) |
2000 | goto done; |
2001 | if (nr_pages == 1 && consume_stock(mem)) |
2002 | goto done; |
2003 | css_get(&mem->css); |
2004 | } else { |
2005 | struct task_struct *p; |
2006 | |
2007 | rcu_read_lock(); |
2008 | p = rcu_dereference(mm->owner); |
2009 | /* |
2010 | * Because we don't have task_lock(), "p" can exit. |
2011 | * In that case, "mem" can point to root or p can be NULL with |
2012 | * race with swapoff. Then, we have small risk of mis-accouning. |
2013 | * But such kind of mis-account by race always happens because |
2014 | * we don't have cgroup_mutex(). It's overkill and we allo that |
2015 | * small race, here. |
2016 | * (*) swapoff at el will charge against mm-struct not against |
2017 | * task-struct. So, mm->owner can be NULL. |
2018 | */ |
2019 | mem = mem_cgroup_from_task(p); |
2020 | if (!mem || mem_cgroup_is_root(mem)) { |
2021 | rcu_read_unlock(); |
2022 | goto done; |
2023 | } |
2024 | if (nr_pages == 1 && consume_stock(mem)) { |
2025 | /* |
2026 | * It seems dagerous to access memcg without css_get(). |
2027 | * But considering how consume_stok works, it's not |
2028 | * necessary. If consume_stock success, some charges |
2029 | * from this memcg are cached on this cpu. So, we |
2030 | * don't need to call css_get()/css_tryget() before |
2031 | * calling consume_stock(). |
2032 | */ |
2033 | rcu_read_unlock(); |
2034 | goto done; |
2035 | } |
2036 | /* after here, we may be blocked. we need to get refcnt */ |
2037 | if (!css_tryget(&mem->css)) { |
2038 | rcu_read_unlock(); |
2039 | goto again; |
2040 | } |
2041 | rcu_read_unlock(); |
2042 | } |
2043 | |
2044 | do { |
2045 | bool oom_check; |
2046 | |
2047 | /* If killed, bypass charge */ |
2048 | if (fatal_signal_pending(current)) { |
2049 | css_put(&mem->css); |
2050 | goto bypass; |
2051 | } |
2052 | |
2053 | oom_check = false; |
2054 | if (oom && !nr_oom_retries) { |
2055 | oom_check = true; |
2056 | nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; |
2057 | } |
2058 | |
2059 | ret = mem_cgroup_do_charge(mem, gfp_mask, batch, oom_check); |
2060 | switch (ret) { |
2061 | case CHARGE_OK: |
2062 | break; |
2063 | case CHARGE_RETRY: /* not in OOM situation but retry */ |
2064 | batch = nr_pages; |
2065 | css_put(&mem->css); |
2066 | mem = NULL; |
2067 | goto again; |
2068 | case CHARGE_WOULDBLOCK: /* !__GFP_WAIT */ |
2069 | css_put(&mem->css); |
2070 | goto nomem; |
2071 | case CHARGE_NOMEM: /* OOM routine works */ |
2072 | if (!oom) { |
2073 | css_put(&mem->css); |
2074 | goto nomem; |
2075 | } |
2076 | /* If oom, we never return -ENOMEM */ |
2077 | nr_oom_retries--; |
2078 | break; |
2079 | case CHARGE_OOM_DIE: /* Killed by OOM Killer */ |
2080 | css_put(&mem->css); |
2081 | goto bypass; |
2082 | } |
2083 | } while (ret != CHARGE_OK); |
2084 | |
2085 | if (batch > nr_pages) |
2086 | refill_stock(mem, batch - nr_pages); |
2087 | css_put(&mem->css); |
2088 | done: |
2089 | *memcg = mem; |
2090 | return 0; |
2091 | nomem: |
2092 | *memcg = NULL; |
2093 | return -ENOMEM; |
2094 | bypass: |
2095 | *memcg = NULL; |
2096 | return 0; |
2097 | } |
2098 | |
2099 | /* |
2100 | * Somemtimes we have to undo a charge we got by try_charge(). |
2101 | * This function is for that and do uncharge, put css's refcnt. |
2102 | * gotten by try_charge(). |
2103 | */ |
2104 | static void __mem_cgroup_cancel_charge(struct mem_cgroup *mem, |
2105 | unsigned int nr_pages) |
2106 | { |
2107 | if (!mem_cgroup_is_root(mem)) { |
2108 | unsigned long bytes = nr_pages * PAGE_SIZE; |
2109 | |
2110 | res_counter_uncharge(&mem->res, bytes); |
2111 | if (do_swap_account) |
2112 | res_counter_uncharge(&mem->memsw, bytes); |
2113 | } |
2114 | } |
2115 | |
2116 | /* |
2117 | * A helper function to get mem_cgroup from ID. must be called under |
2118 | * rcu_read_lock(). The caller must check css_is_removed() or some if |
2119 | * it's concern. (dropping refcnt from swap can be called against removed |
2120 | * memcg.) |
2121 | */ |
2122 | static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) |
2123 | { |
2124 | struct cgroup_subsys_state *css; |
2125 | |
2126 | /* ID 0 is unused ID */ |
2127 | if (!id) |
2128 | return NULL; |
2129 | css = css_lookup(&mem_cgroup_subsys, id); |
2130 | if (!css) |
2131 | return NULL; |
2132 | return container_of(css, struct mem_cgroup, css); |
2133 | } |
2134 | |
2135 | struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) |
2136 | { |
2137 | struct mem_cgroup *mem = NULL; |
2138 | struct page_cgroup *pc; |
2139 | unsigned short id; |
2140 | swp_entry_t ent; |
2141 | |
2142 | VM_BUG_ON(!PageLocked(page)); |
2143 | |
2144 | pc = lookup_page_cgroup(page); |
2145 | lock_page_cgroup(pc); |
2146 | if (PageCgroupUsed(pc)) { |
2147 | mem = pc->mem_cgroup; |
2148 | if (mem && !css_tryget(&mem->css)) |
2149 | mem = NULL; |
2150 | } else if (PageSwapCache(page)) { |
2151 | ent.val = page_private(page); |
2152 | id = lookup_swap_cgroup(ent); |
2153 | rcu_read_lock(); |
2154 | mem = mem_cgroup_lookup(id); |
2155 | if (mem && !css_tryget(&mem->css)) |
2156 | mem = NULL; |
2157 | rcu_read_unlock(); |
2158 | } |
2159 | unlock_page_cgroup(pc); |
2160 | return mem; |
2161 | } |
2162 | |
2163 | static void __mem_cgroup_commit_charge(struct mem_cgroup *mem, |
2164 | struct page *page, |
2165 | unsigned int nr_pages, |
2166 | struct page_cgroup *pc, |
2167 | enum charge_type ctype) |
2168 | { |
2169 | lock_page_cgroup(pc); |
2170 | if (unlikely(PageCgroupUsed(pc))) { |
2171 | unlock_page_cgroup(pc); |
2172 | __mem_cgroup_cancel_charge(mem, nr_pages); |
2173 | return; |
2174 | } |
2175 | /* |
2176 | * we don't need page_cgroup_lock about tail pages, becase they are not |
2177 | * accessed by any other context at this point. |
2178 | */ |
2179 | pc->mem_cgroup = mem; |
2180 | /* |
2181 | * We access a page_cgroup asynchronously without lock_page_cgroup(). |
2182 | * Especially when a page_cgroup is taken from a page, pc->mem_cgroup |
2183 | * is accessed after testing USED bit. To make pc->mem_cgroup visible |
2184 | * before USED bit, we need memory barrier here. |
2185 | * See mem_cgroup_add_lru_list(), etc. |
2186 | */ |
2187 | smp_wmb(); |
2188 | switch (ctype) { |
2189 | case MEM_CGROUP_CHARGE_TYPE_CACHE: |
2190 | case MEM_CGROUP_CHARGE_TYPE_SHMEM: |
2191 | SetPageCgroupCache(pc); |
2192 | SetPageCgroupUsed(pc); |
2193 | break; |
2194 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: |
2195 | ClearPageCgroupCache(pc); |
2196 | SetPageCgroupUsed(pc); |
2197 | break; |
2198 | default: |
2199 | break; |
2200 | } |
2201 | |
2202 | mem_cgroup_charge_statistics(mem, PageCgroupCache(pc), nr_pages); |
2203 | unlock_page_cgroup(pc); |
2204 | /* |
2205 | * "charge_statistics" updated event counter. Then, check it. |
2206 | * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree. |
2207 | * if they exceeds softlimit. |
2208 | */ |
2209 | memcg_check_events(mem, page); |
2210 | } |
2211 | |
2212 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
2213 | |
2214 | #define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) | (1 << PCG_MOVE_LOCK) |\ |
2215 | (1 << PCG_ACCT_LRU) | (1 << PCG_MIGRATION)) |
2216 | /* |
2217 | * Because tail pages are not marked as "used", set it. We're under |
2218 | * zone->lru_lock, 'splitting on pmd' and compund_lock. |
2219 | */ |
2220 | void mem_cgroup_split_huge_fixup(struct page *head, struct page *tail) |
2221 | { |
2222 | struct page_cgroup *head_pc = lookup_page_cgroup(head); |
2223 | struct page_cgroup *tail_pc = lookup_page_cgroup(tail); |
2224 | unsigned long flags; |
2225 | |
2226 | if (mem_cgroup_disabled()) |
2227 | return; |
2228 | /* |
2229 | * We have no races with charge/uncharge but will have races with |
2230 | * page state accounting. |
2231 | */ |
2232 | move_lock_page_cgroup(head_pc, &flags); |
2233 | |
2234 | tail_pc->mem_cgroup = head_pc->mem_cgroup; |
2235 | smp_wmb(); /* see __commit_charge() */ |
2236 | if (PageCgroupAcctLRU(head_pc)) { |
2237 | enum lru_list lru; |
2238 | struct mem_cgroup_per_zone *mz; |
2239 | |
2240 | /* |
2241 | * LRU flags cannot be copied because we need to add tail |
2242 | *.page to LRU by generic call and our hook will be called. |
2243 | * We hold lru_lock, then, reduce counter directly. |
2244 | */ |
2245 | lru = page_lru(head); |
2246 | mz = page_cgroup_zoneinfo(head_pc->mem_cgroup, head); |
2247 | MEM_CGROUP_ZSTAT(mz, lru) -= 1; |
2248 | } |
2249 | tail_pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT; |
2250 | move_unlock_page_cgroup(head_pc, &flags); |
2251 | } |
2252 | #endif |
2253 | |
2254 | /** |
2255 | * mem_cgroup_move_account - move account of the page |
2256 | * @page: the page |
2257 | * @nr_pages: number of regular pages (>1 for huge pages) |
2258 | * @pc: page_cgroup of the page. |
2259 | * @from: mem_cgroup which the page is moved from. |
2260 | * @to: mem_cgroup which the page is moved to. @from != @to. |
2261 | * @uncharge: whether we should call uncharge and css_put against @from. |
2262 | * |
2263 | * The caller must confirm following. |
2264 | * - page is not on LRU (isolate_page() is useful.) |
2265 | * - compound_lock is held when nr_pages > 1 |
2266 | * |
2267 | * This function doesn't do "charge" nor css_get to new cgroup. It should be |
2268 | * done by a caller(__mem_cgroup_try_charge would be useful). If @uncharge is |
2269 | * true, this function does "uncharge" from old cgroup, but it doesn't if |
2270 | * @uncharge is false, so a caller should do "uncharge". |
2271 | */ |
2272 | static int mem_cgroup_move_account(struct page *page, |
2273 | unsigned int nr_pages, |
2274 | struct page_cgroup *pc, |
2275 | struct mem_cgroup *from, |
2276 | struct mem_cgroup *to, |
2277 | bool uncharge) |
2278 | { |
2279 | unsigned long flags; |
2280 | int ret; |
2281 | |
2282 | VM_BUG_ON(from == to); |
2283 | VM_BUG_ON(PageLRU(page)); |
2284 | /* |
2285 | * The page is isolated from LRU. So, collapse function |
2286 | * will not handle this page. But page splitting can happen. |
2287 | * Do this check under compound_page_lock(). The caller should |
2288 | * hold it. |
2289 | */ |
2290 | ret = -EBUSY; |
2291 | if (nr_pages > 1 && !PageTransHuge(page)) |
2292 | goto out; |
2293 | |
2294 | lock_page_cgroup(pc); |
2295 | |
2296 | ret = -EINVAL; |
2297 | if (!PageCgroupUsed(pc) || pc->mem_cgroup != from) |
2298 | goto unlock; |
2299 | |
2300 | move_lock_page_cgroup(pc, &flags); |
2301 | |
2302 | if (PageCgroupFileMapped(pc)) { |
2303 | /* Update mapped_file data for mem_cgroup */ |
2304 | preempt_disable(); |
2305 | __this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); |
2306 | __this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); |
2307 | preempt_enable(); |
2308 | } |
2309 | mem_cgroup_charge_statistics(from, PageCgroupCache(pc), -nr_pages); |
2310 | if (uncharge) |
2311 | /* This is not "cancel", but cancel_charge does all we need. */ |
2312 | __mem_cgroup_cancel_charge(from, nr_pages); |
2313 | |
2314 | /* caller should have done css_get */ |
2315 | pc->mem_cgroup = to; |
2316 | mem_cgroup_charge_statistics(to, PageCgroupCache(pc), nr_pages); |
2317 | /* |
2318 | * We charges against "to" which may not have any tasks. Then, "to" |
2319 | * can be under rmdir(). But in current implementation, caller of |
2320 | * this function is just force_empty() and move charge, so it's |
2321 | * guaranteed that "to" is never removed. So, we don't check rmdir |
2322 | * status here. |
2323 | */ |
2324 | move_unlock_page_cgroup(pc, &flags); |
2325 | ret = 0; |
2326 | unlock: |
2327 | unlock_page_cgroup(pc); |
2328 | /* |
2329 | * check events |
2330 | */ |
2331 | memcg_check_events(to, page); |
2332 | memcg_check_events(from, page); |
2333 | out: |
2334 | return ret; |
2335 | } |
2336 | |
2337 | /* |
2338 | * move charges to its parent. |
2339 | */ |
2340 | |
2341 | static int mem_cgroup_move_parent(struct page *page, |
2342 | struct page_cgroup *pc, |
2343 | struct mem_cgroup *child, |
2344 | gfp_t gfp_mask) |
2345 | { |
2346 | struct cgroup *cg = child->css.cgroup; |
2347 | struct cgroup *pcg = cg->parent; |
2348 | struct mem_cgroup *parent; |
2349 | unsigned int nr_pages; |
2350 | unsigned long uninitialized_var(flags); |
2351 | int ret; |
2352 | |
2353 | /* Is ROOT ? */ |
2354 | if (!pcg) |
2355 | return -EINVAL; |
2356 | |
2357 | ret = -EBUSY; |
2358 | if (!get_page_unless_zero(page)) |
2359 | goto out; |
2360 | if (isolate_lru_page(page)) |
2361 | goto put; |
2362 | |
2363 | nr_pages = hpage_nr_pages(page); |
2364 | |
2365 | parent = mem_cgroup_from_cont(pcg); |
2366 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, nr_pages, &parent, false); |
2367 | if (ret || !parent) |
2368 | goto put_back; |
2369 | |
2370 | if (nr_pages > 1) |
2371 | flags = compound_lock_irqsave(page); |
2372 | |
2373 | ret = mem_cgroup_move_account(page, nr_pages, pc, child, parent, true); |
2374 | if (ret) |
2375 | __mem_cgroup_cancel_charge(parent, nr_pages); |
2376 | |
2377 | if (nr_pages > 1) |
2378 | compound_unlock_irqrestore(page, flags); |
2379 | put_back: |
2380 | putback_lru_page(page); |
2381 | put: |
2382 | put_page(page); |
2383 | out: |
2384 | return ret; |
2385 | } |
2386 | |
2387 | /* |
2388 | * Charge the memory controller for page usage. |
2389 | * Return |
2390 | * 0 if the charge was successful |
2391 | * < 0 if the cgroup is over its limit |
2392 | */ |
2393 | static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, |
2394 | gfp_t gfp_mask, enum charge_type ctype) |
2395 | { |
2396 | struct mem_cgroup *mem = NULL; |
2397 | unsigned int nr_pages = 1; |
2398 | struct page_cgroup *pc; |
2399 | bool oom = true; |
2400 | int ret; |
2401 | |
2402 | if (PageTransHuge(page)) { |
2403 | nr_pages <<= compound_order(page); |
2404 | VM_BUG_ON(!PageTransHuge(page)); |
2405 | /* |
2406 | * Never OOM-kill a process for a huge page. The |
2407 | * fault handler will fall back to regular pages. |
2408 | */ |
2409 | oom = false; |
2410 | } |
2411 | |
2412 | pc = lookup_page_cgroup(page); |
2413 | BUG_ON(!pc); /* XXX: remove this and move pc lookup into commit */ |
2414 | |
2415 | ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &mem, oom); |
2416 | if (ret || !mem) |
2417 | return ret; |
2418 | |
2419 | __mem_cgroup_commit_charge(mem, page, nr_pages, pc, ctype); |
2420 | return 0; |
2421 | } |
2422 | |
2423 | int mem_cgroup_newpage_charge(struct page *page, |
2424 | struct mm_struct *mm, gfp_t gfp_mask) |
2425 | { |
2426 | if (mem_cgroup_disabled()) |
2427 | return 0; |
2428 | /* |
2429 | * If already mapped, we don't have to account. |
2430 | * If page cache, page->mapping has address_space. |
2431 | * But page->mapping may have out-of-use anon_vma pointer, |
2432 | * detecit it by PageAnon() check. newly-mapped-anon's page->mapping |
2433 | * is NULL. |
2434 | */ |
2435 | if (page_mapped(page) || (page->mapping && !PageAnon(page))) |
2436 | return 0; |
2437 | if (unlikely(!mm)) |
2438 | mm = &init_mm; |
2439 | return mem_cgroup_charge_common(page, mm, gfp_mask, |
2440 | MEM_CGROUP_CHARGE_TYPE_MAPPED); |
2441 | } |
2442 | |
2443 | static void |
2444 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, |
2445 | enum charge_type ctype); |
2446 | |
2447 | static void |
2448 | __mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *mem, |
2449 | enum charge_type ctype) |
2450 | { |
2451 | struct page_cgroup *pc = lookup_page_cgroup(page); |
2452 | /* |
2453 | * In some case, SwapCache, FUSE(splice_buf->radixtree), the page |
2454 | * is already on LRU. It means the page may on some other page_cgroup's |
2455 | * LRU. Take care of it. |
2456 | */ |
2457 | mem_cgroup_lru_del_before_commit(page); |
2458 | __mem_cgroup_commit_charge(mem, page, 1, pc, ctype); |
2459 | mem_cgroup_lru_add_after_commit(page); |
2460 | return; |
2461 | } |
2462 | |
2463 | int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, |
2464 | gfp_t gfp_mask) |
2465 | { |
2466 | struct mem_cgroup *mem = NULL; |
2467 | int ret; |
2468 | |
2469 | if (mem_cgroup_disabled()) |
2470 | return 0; |
2471 | if (PageCompound(page)) |
2472 | return 0; |
2473 | /* |
2474 | * Corner case handling. This is called from add_to_page_cache() |
2475 | * in usual. But some FS (shmem) precharges this page before calling it |
2476 | * and call add_to_page_cache() with GFP_NOWAIT. |
2477 | * |
2478 | * For GFP_NOWAIT case, the page may be pre-charged before calling |
2479 | * add_to_page_cache(). (See shmem.c) check it here and avoid to call |
2480 | * charge twice. (It works but has to pay a bit larger cost.) |
2481 | * And when the page is SwapCache, it should take swap information |
2482 | * into account. This is under lock_page() now. |
2483 | */ |
2484 | if (!(gfp_mask & __GFP_WAIT)) { |
2485 | struct page_cgroup *pc; |
2486 | |
2487 | pc = lookup_page_cgroup(page); |
2488 | if (!pc) |
2489 | return 0; |
2490 | lock_page_cgroup(pc); |
2491 | if (PageCgroupUsed(pc)) { |
2492 | unlock_page_cgroup(pc); |
2493 | return 0; |
2494 | } |
2495 | unlock_page_cgroup(pc); |
2496 | } |
2497 | |
2498 | if (unlikely(!mm)) |
2499 | mm = &init_mm; |
2500 | |
2501 | if (page_is_file_cache(page)) { |
2502 | ret = __mem_cgroup_try_charge(mm, gfp_mask, 1, &mem, true); |
2503 | if (ret || !mem) |
2504 | return ret; |
2505 | |
2506 | /* |
2507 | * FUSE reuses pages without going through the final |
2508 | * put that would remove them from the LRU list, make |
2509 | * sure that they get relinked properly. |
2510 | */ |
2511 | __mem_cgroup_commit_charge_lrucare(page, mem, |
2512 | MEM_CGROUP_CHARGE_TYPE_CACHE); |
2513 | return ret; |
2514 | } |
2515 | /* shmem */ |
2516 | if (PageSwapCache(page)) { |
2517 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); |
2518 | if (!ret) |
2519 | __mem_cgroup_commit_charge_swapin(page, mem, |
2520 | MEM_CGROUP_CHARGE_TYPE_SHMEM); |
2521 | } else |
2522 | ret = mem_cgroup_charge_common(page, mm, gfp_mask, |
2523 | MEM_CGROUP_CHARGE_TYPE_SHMEM); |
2524 | |
2525 | return ret; |
2526 | } |
2527 | |
2528 | /* |
2529 | * While swap-in, try_charge -> commit or cancel, the page is locked. |
2530 | * And when try_charge() successfully returns, one refcnt to memcg without |
2531 | * struct page_cgroup is acquired. This refcnt will be consumed by |
2532 | * "commit()" or removed by "cancel()" |
2533 | */ |
2534 | int mem_cgroup_try_charge_swapin(struct mm_struct *mm, |
2535 | struct page *page, |
2536 | gfp_t mask, struct mem_cgroup **ptr) |
2537 | { |
2538 | struct mem_cgroup *mem; |
2539 | int ret; |
2540 | |
2541 | *ptr = NULL; |
2542 | |
2543 | if (mem_cgroup_disabled()) |
2544 | return 0; |
2545 | |
2546 | if (!do_swap_account) |
2547 | goto charge_cur_mm; |
2548 | /* |
2549 | * A racing thread's fault, or swapoff, may have already updated |
2550 | * the pte, and even removed page from swap cache: in those cases |
2551 | * do_swap_page()'s pte_same() test will fail; but there's also a |
2552 | * KSM case which does need to charge the page. |
2553 | */ |
2554 | if (!PageSwapCache(page)) |
2555 | goto charge_cur_mm; |
2556 | mem = try_get_mem_cgroup_from_page(page); |
2557 | if (!mem) |
2558 | goto charge_cur_mm; |
2559 | *ptr = mem; |
2560 | ret = __mem_cgroup_try_charge(NULL, mask, 1, ptr, true); |
2561 | css_put(&mem->css); |
2562 | return ret; |
2563 | charge_cur_mm: |
2564 | if (unlikely(!mm)) |
2565 | mm = &init_mm; |
2566 | return __mem_cgroup_try_charge(mm, mask, 1, ptr, true); |
2567 | } |
2568 | |
2569 | static void |
2570 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, |
2571 | enum charge_type ctype) |
2572 | { |
2573 | if (mem_cgroup_disabled()) |
2574 | return; |
2575 | if (!ptr) |
2576 | return; |
2577 | cgroup_exclude_rmdir(&ptr->css); |
2578 | |
2579 | __mem_cgroup_commit_charge_lrucare(page, ptr, ctype); |
2580 | /* |
2581 | * Now swap is on-memory. This means this page may be |
2582 | * counted both as mem and swap....double count. |
2583 | * Fix it by uncharging from memsw. Basically, this SwapCache is stable |
2584 | * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page() |
2585 | * may call delete_from_swap_cache() before reach here. |
2586 | */ |
2587 | if (do_swap_account && PageSwapCache(page)) { |
2588 | swp_entry_t ent = {.val = page_private(page)}; |
2589 | unsigned short id; |
2590 | struct mem_cgroup *memcg; |
2591 | |
2592 | id = swap_cgroup_record(ent, 0); |
2593 | rcu_read_lock(); |
2594 | memcg = mem_cgroup_lookup(id); |
2595 | if (memcg) { |
2596 | /* |
2597 | * This recorded memcg can be obsolete one. So, avoid |
2598 | * calling css_tryget |
2599 | */ |
2600 | if (!mem_cgroup_is_root(memcg)) |
2601 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
2602 | mem_cgroup_swap_statistics(memcg, false); |
2603 | mem_cgroup_put(memcg); |
2604 | } |
2605 | rcu_read_unlock(); |
2606 | } |
2607 | /* |
2608 | * At swapin, we may charge account against cgroup which has no tasks. |
2609 | * So, rmdir()->pre_destroy() can be called while we do this charge. |
2610 | * In that case, we need to call pre_destroy() again. check it here. |
2611 | */ |
2612 | cgroup_release_and_wakeup_rmdir(&ptr->css); |
2613 | } |
2614 | |
2615 | void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) |
2616 | { |
2617 | __mem_cgroup_commit_charge_swapin(page, ptr, |
2618 | MEM_CGROUP_CHARGE_TYPE_MAPPED); |
2619 | } |
2620 | |
2621 | void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem) |
2622 | { |
2623 | if (mem_cgroup_disabled()) |
2624 | return; |
2625 | if (!mem) |
2626 | return; |
2627 | __mem_cgroup_cancel_charge(mem, 1); |
2628 | } |
2629 | |
2630 | static void mem_cgroup_do_uncharge(struct mem_cgroup *mem, |
2631 | unsigned int nr_pages, |
2632 | const enum charge_type ctype) |
2633 | { |
2634 | struct memcg_batch_info *batch = NULL; |
2635 | bool uncharge_memsw = true; |
2636 | |
2637 | /* If swapout, usage of swap doesn't decrease */ |
2638 | if (!do_swap_account || ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) |
2639 | uncharge_memsw = false; |
2640 | |
2641 | batch = ¤t->memcg_batch; |
2642 | /* |
2643 | * In usual, we do css_get() when we remember memcg pointer. |
2644 | * But in this case, we keep res->usage until end of a series of |
2645 | * uncharges. Then, it's ok to ignore memcg's refcnt. |
2646 | */ |
2647 | if (!batch->memcg) |
2648 | batch->memcg = mem; |
2649 | /* |
2650 | * do_batch > 0 when unmapping pages or inode invalidate/truncate. |
2651 | * In those cases, all pages freed continuously can be expected to be in |
2652 | * the same cgroup and we have chance to coalesce uncharges. |
2653 | * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE) |
2654 | * because we want to do uncharge as soon as possible. |
2655 | */ |
2656 | |
2657 | if (!batch->do_batch || test_thread_flag(TIF_MEMDIE)) |
2658 | goto direct_uncharge; |
2659 | |
2660 | if (nr_pages > 1) |
2661 | goto direct_uncharge; |
2662 | |
2663 | /* |
2664 | * In typical case, batch->memcg == mem. This means we can |
2665 | * merge a series of uncharges to an uncharge of res_counter. |
2666 | * If not, we uncharge res_counter ony by one. |
2667 | */ |
2668 | if (batch->memcg != mem) |
2669 | goto direct_uncharge; |
2670 | /* remember freed charge and uncharge it later */ |
2671 | batch->nr_pages++; |
2672 | if (uncharge_memsw) |
2673 | batch->memsw_nr_pages++; |
2674 | return; |
2675 | direct_uncharge: |
2676 | res_counter_uncharge(&mem->res, nr_pages * PAGE_SIZE); |
2677 | if (uncharge_memsw) |
2678 | res_counter_uncharge(&mem->memsw, nr_pages * PAGE_SIZE); |
2679 | if (unlikely(batch->memcg != mem)) |
2680 | memcg_oom_recover(mem); |
2681 | return; |
2682 | } |
2683 | |
2684 | /* |
2685 | * uncharge if !page_mapped(page) |
2686 | */ |
2687 | static struct mem_cgroup * |
2688 | __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) |
2689 | { |
2690 | struct mem_cgroup *mem = NULL; |
2691 | unsigned int nr_pages = 1; |
2692 | struct page_cgroup *pc; |
2693 | |
2694 | if (mem_cgroup_disabled()) |
2695 | return NULL; |
2696 | |
2697 | if (PageSwapCache(page)) |
2698 | return NULL; |
2699 | |
2700 | if (PageTransHuge(page)) { |
2701 | nr_pages <<= compound_order(page); |
2702 | VM_BUG_ON(!PageTransHuge(page)); |
2703 | } |
2704 | /* |
2705 | * Check if our page_cgroup is valid |
2706 | */ |
2707 | pc = lookup_page_cgroup(page); |
2708 | if (unlikely(!pc || !PageCgroupUsed(pc))) |
2709 | return NULL; |
2710 | |
2711 | lock_page_cgroup(pc); |
2712 | |
2713 | mem = pc->mem_cgroup; |
2714 | |
2715 | if (!PageCgroupUsed(pc)) |
2716 | goto unlock_out; |
2717 | |
2718 | switch (ctype) { |
2719 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: |
2720 | case MEM_CGROUP_CHARGE_TYPE_DROP: |
2721 | /* See mem_cgroup_prepare_migration() */ |
2722 | if (page_mapped(page) || PageCgroupMigration(pc)) |
2723 | goto unlock_out; |
2724 | break; |
2725 | case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: |
2726 | if (!PageAnon(page)) { /* Shared memory */ |
2727 | if (page->mapping && !page_is_file_cache(page)) |
2728 | goto unlock_out; |
2729 | } else if (page_mapped(page)) /* Anon */ |
2730 | goto unlock_out; |
2731 | break; |
2732 | default: |
2733 | break; |
2734 | } |
2735 | |
2736 | mem_cgroup_charge_statistics(mem, PageCgroupCache(pc), -nr_pages); |
2737 | |
2738 | ClearPageCgroupUsed(pc); |
2739 | /* |
2740 | * pc->mem_cgroup is not cleared here. It will be accessed when it's |
2741 | * freed from LRU. This is safe because uncharged page is expected not |
2742 | * to be reused (freed soon). Exception is SwapCache, it's handled by |
2743 | * special functions. |
2744 | */ |
2745 | |
2746 | unlock_page_cgroup(pc); |
2747 | /* |
2748 | * even after unlock, we have mem->res.usage here and this memcg |
2749 | * will never be freed. |
2750 | */ |
2751 | memcg_check_events(mem, page); |
2752 | if (do_swap_account && ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) { |
2753 | mem_cgroup_swap_statistics(mem, true); |
2754 | mem_cgroup_get(mem); |
2755 | } |
2756 | if (!mem_cgroup_is_root(mem)) |
2757 | mem_cgroup_do_uncharge(mem, nr_pages, ctype); |
2758 | |
2759 | return mem; |
2760 | |
2761 | unlock_out: |
2762 | unlock_page_cgroup(pc); |
2763 | return NULL; |
2764 | } |
2765 | |
2766 | void mem_cgroup_uncharge_page(struct page *page) |
2767 | { |
2768 | /* early check. */ |
2769 | if (page_mapped(page)) |
2770 | return; |
2771 | if (page->mapping && !PageAnon(page)) |
2772 | return; |
2773 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED); |
2774 | } |
2775 | |
2776 | void mem_cgroup_uncharge_cache_page(struct page *page) |
2777 | { |
2778 | VM_BUG_ON(page_mapped(page)); |
2779 | VM_BUG_ON(page->mapping); |
2780 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); |
2781 | } |
2782 | |
2783 | /* |
2784 | * Batch_start/batch_end is called in unmap_page_range/invlidate/trucate. |
2785 | * In that cases, pages are freed continuously and we can expect pages |
2786 | * are in the same memcg. All these calls itself limits the number of |
2787 | * pages freed at once, then uncharge_start/end() is called properly. |
2788 | * This may be called prural(2) times in a context, |
2789 | */ |
2790 | |
2791 | void mem_cgroup_uncharge_start(void) |
2792 | { |
2793 | current->memcg_batch.do_batch++; |
2794 | /* We can do nest. */ |
2795 | if (current->memcg_batch.do_batch == 1) { |
2796 | current->memcg_batch.memcg = NULL; |
2797 | current->memcg_batch.nr_pages = 0; |
2798 | current->memcg_batch.memsw_nr_pages = 0; |
2799 | } |
2800 | } |
2801 | |
2802 | void mem_cgroup_uncharge_end(void) |
2803 | { |
2804 | struct memcg_batch_info *batch = ¤t->memcg_batch; |
2805 | |
2806 | if (!batch->do_batch) |
2807 | return; |
2808 | |
2809 | batch->do_batch--; |
2810 | if (batch->do_batch) /* If stacked, do nothing. */ |
2811 | return; |
2812 | |
2813 | if (!batch->memcg) |
2814 | return; |
2815 | /* |
2816 | * This "batch->memcg" is valid without any css_get/put etc... |
2817 | * bacause we hide charges behind us. |
2818 | */ |
2819 | if (batch->nr_pages) |
2820 | res_counter_uncharge(&batch->memcg->res, |
2821 | batch->nr_pages * PAGE_SIZE); |
2822 | if (batch->memsw_nr_pages) |
2823 | res_counter_uncharge(&batch->memcg->memsw, |
2824 | batch->memsw_nr_pages * PAGE_SIZE); |
2825 | memcg_oom_recover(batch->memcg); |
2826 | /* forget this pointer (for sanity check) */ |
2827 | batch->memcg = NULL; |
2828 | } |
2829 | |
2830 | #ifdef CONFIG_SWAP |
2831 | /* |
2832 | * called after __delete_from_swap_cache() and drop "page" account. |
2833 | * memcg information is recorded to swap_cgroup of "ent" |
2834 | */ |
2835 | void |
2836 | mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout) |
2837 | { |
2838 | struct mem_cgroup *memcg; |
2839 | int ctype = MEM_CGROUP_CHARGE_TYPE_SWAPOUT; |
2840 | |
2841 | if (!swapout) /* this was a swap cache but the swap is unused ! */ |
2842 | ctype = MEM_CGROUP_CHARGE_TYPE_DROP; |
2843 | |
2844 | memcg = __mem_cgroup_uncharge_common(page, ctype); |
2845 | |
2846 | /* |
2847 | * record memcg information, if swapout && memcg != NULL, |
2848 | * mem_cgroup_get() was called in uncharge(). |
2849 | */ |
2850 | if (do_swap_account && swapout && memcg) |
2851 | swap_cgroup_record(ent, css_id(&memcg->css)); |
2852 | } |
2853 | #endif |
2854 | |
2855 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
2856 | /* |
2857 | * called from swap_entry_free(). remove record in swap_cgroup and |
2858 | * uncharge "memsw" account. |
2859 | */ |
2860 | void mem_cgroup_uncharge_swap(swp_entry_t ent) |
2861 | { |
2862 | struct mem_cgroup *memcg; |
2863 | unsigned short id; |
2864 | |
2865 | if (!do_swap_account) |
2866 | return; |
2867 | |
2868 | id = swap_cgroup_record(ent, 0); |
2869 | rcu_read_lock(); |
2870 | memcg = mem_cgroup_lookup(id); |
2871 | if (memcg) { |
2872 | /* |
2873 | * We uncharge this because swap is freed. |
2874 | * This memcg can be obsolete one. We avoid calling css_tryget |
2875 | */ |
2876 | if (!mem_cgroup_is_root(memcg)) |
2877 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
2878 | mem_cgroup_swap_statistics(memcg, false); |
2879 | mem_cgroup_put(memcg); |
2880 | } |
2881 | rcu_read_unlock(); |
2882 | } |
2883 | |
2884 | /** |
2885 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. |
2886 | * @entry: swap entry to be moved |
2887 | * @from: mem_cgroup which the entry is moved from |
2888 | * @to: mem_cgroup which the entry is moved to |
2889 | * @need_fixup: whether we should fixup res_counters and refcounts. |
2890 | * |
2891 | * It succeeds only when the swap_cgroup's record for this entry is the same |
2892 | * as the mem_cgroup's id of @from. |
2893 | * |
2894 | * Returns 0 on success, -EINVAL on failure. |
2895 | * |
2896 | * The caller must have charged to @to, IOW, called res_counter_charge() about |
2897 | * both res and memsw, and called css_get(). |
2898 | */ |
2899 | static int mem_cgroup_move_swap_account(swp_entry_t entry, |
2900 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
2901 | { |
2902 | unsigned short old_id, new_id; |
2903 | |
2904 | old_id = css_id(&from->css); |
2905 | new_id = css_id(&to->css); |
2906 | |
2907 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { |
2908 | mem_cgroup_swap_statistics(from, false); |
2909 | mem_cgroup_swap_statistics(to, true); |
2910 | /* |
2911 | * This function is only called from task migration context now. |
2912 | * It postpones res_counter and refcount handling till the end |
2913 | * of task migration(mem_cgroup_clear_mc()) for performance |
2914 | * improvement. But we cannot postpone mem_cgroup_get(to) |
2915 | * because if the process that has been moved to @to does |
2916 | * swap-in, the refcount of @to might be decreased to 0. |
2917 | */ |
2918 | mem_cgroup_get(to); |
2919 | if (need_fixup) { |
2920 | if (!mem_cgroup_is_root(from)) |
2921 | res_counter_uncharge(&from->memsw, PAGE_SIZE); |
2922 | mem_cgroup_put(from); |
2923 | /* |
2924 | * we charged both to->res and to->memsw, so we should |
2925 | * uncharge to->res. |
2926 | */ |
2927 | if (!mem_cgroup_is_root(to)) |
2928 | res_counter_uncharge(&to->res, PAGE_SIZE); |
2929 | } |
2930 | return 0; |
2931 | } |
2932 | return -EINVAL; |
2933 | } |
2934 | #else |
2935 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, |
2936 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
2937 | { |
2938 | return -EINVAL; |
2939 | } |
2940 | #endif |
2941 | |
2942 | /* |
2943 | * Before starting migration, account PAGE_SIZE to mem_cgroup that the old |
2944 | * page belongs to. |
2945 | */ |
2946 | int mem_cgroup_prepare_migration(struct page *page, |
2947 | struct page *newpage, struct mem_cgroup **ptr, gfp_t gfp_mask) |
2948 | { |
2949 | struct mem_cgroup *mem = NULL; |
2950 | struct page_cgroup *pc; |
2951 | enum charge_type ctype; |
2952 | int ret = 0; |
2953 | |
2954 | *ptr = NULL; |
2955 | |
2956 | VM_BUG_ON(PageTransHuge(page)); |
2957 | if (mem_cgroup_disabled()) |
2958 | return 0; |
2959 | |
2960 | pc = lookup_page_cgroup(page); |
2961 | lock_page_cgroup(pc); |
2962 | if (PageCgroupUsed(pc)) { |
2963 | mem = pc->mem_cgroup; |
2964 | css_get(&mem->css); |
2965 | /* |
2966 | * At migrating an anonymous page, its mapcount goes down |
2967 | * to 0 and uncharge() will be called. But, even if it's fully |
2968 | * unmapped, migration may fail and this page has to be |
2969 | * charged again. We set MIGRATION flag here and delay uncharge |
2970 | * until end_migration() is called |
2971 | * |
2972 | * Corner Case Thinking |
2973 | * A) |
2974 | * When the old page was mapped as Anon and it's unmap-and-freed |
2975 | * while migration was ongoing. |
2976 | * If unmap finds the old page, uncharge() of it will be delayed |
2977 | * until end_migration(). If unmap finds a new page, it's |
2978 | * uncharged when it make mapcount to be 1->0. If unmap code |
2979 | * finds swap_migration_entry, the new page will not be mapped |
2980 | * and end_migration() will find it(mapcount==0). |
2981 | * |
2982 | * B) |
2983 | * When the old page was mapped but migraion fails, the kernel |
2984 | * remaps it. A charge for it is kept by MIGRATION flag even |
2985 | * if mapcount goes down to 0. We can do remap successfully |
2986 | * without charging it again. |
2987 | * |
2988 | * C) |
2989 | * The "old" page is under lock_page() until the end of |
2990 | * migration, so, the old page itself will not be swapped-out. |
2991 | * If the new page is swapped out before end_migraton, our |
2992 | * hook to usual swap-out path will catch the event. |
2993 | */ |
2994 | if (PageAnon(page)) |
2995 | SetPageCgroupMigration(pc); |
2996 | } |
2997 | unlock_page_cgroup(pc); |
2998 | /* |
2999 | * If the page is not charged at this point, |
3000 | * we return here. |
3001 | */ |
3002 | if (!mem) |
3003 | return 0; |
3004 | |
3005 | *ptr = mem; |
3006 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, 1, ptr, false); |
3007 | css_put(&mem->css);/* drop extra refcnt */ |
3008 | if (ret || *ptr == NULL) { |
3009 | if (PageAnon(page)) { |
3010 | lock_page_cgroup(pc); |
3011 | ClearPageCgroupMigration(pc); |
3012 | unlock_page_cgroup(pc); |
3013 | /* |
3014 | * The old page may be fully unmapped while we kept it. |
3015 | */ |
3016 | mem_cgroup_uncharge_page(page); |
3017 | } |
3018 | return -ENOMEM; |
3019 | } |
3020 | /* |
3021 | * We charge new page before it's used/mapped. So, even if unlock_page() |
3022 | * is called before end_migration, we can catch all events on this new |
3023 | * page. In the case new page is migrated but not remapped, new page's |
3024 | * mapcount will be finally 0 and we call uncharge in end_migration(). |
3025 | */ |
3026 | pc = lookup_page_cgroup(newpage); |
3027 | if (PageAnon(page)) |
3028 | ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED; |
3029 | else if (page_is_file_cache(page)) |
3030 | ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; |
3031 | else |
3032 | ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; |
3033 | __mem_cgroup_commit_charge(mem, page, 1, pc, ctype); |
3034 | return ret; |
3035 | } |
3036 | |
3037 | /* remove redundant charge if migration failed*/ |
3038 | void mem_cgroup_end_migration(struct mem_cgroup *mem, |
3039 | struct page *oldpage, struct page *newpage, bool migration_ok) |
3040 | { |
3041 | struct page *used, *unused; |
3042 | struct page_cgroup *pc; |
3043 | |
3044 | if (!mem) |
3045 | return; |
3046 | /* blocks rmdir() */ |
3047 | cgroup_exclude_rmdir(&mem->css); |
3048 | if (!migration_ok) { |
3049 | used = oldpage; |
3050 | unused = newpage; |
3051 | } else { |
3052 | used = newpage; |
3053 | unused = oldpage; |
3054 | } |
3055 | /* |
3056 | * We disallowed uncharge of pages under migration because mapcount |
3057 | * of the page goes down to zero, temporarly. |
3058 | * Clear the flag and check the page should be charged. |
3059 | */ |
3060 | pc = lookup_page_cgroup(oldpage); |
3061 | lock_page_cgroup(pc); |
3062 | ClearPageCgroupMigration(pc); |
3063 | unlock_page_cgroup(pc); |
3064 | |
3065 | __mem_cgroup_uncharge_common(unused, MEM_CGROUP_CHARGE_TYPE_FORCE); |
3066 | |
3067 | /* |
3068 | * If a page is a file cache, radix-tree replacement is very atomic |
3069 | * and we can skip this check. When it was an Anon page, its mapcount |
3070 | * goes down to 0. But because we added MIGRATION flage, it's not |
3071 | * uncharged yet. There are several case but page->mapcount check |
3072 | * and USED bit check in mem_cgroup_uncharge_page() will do enough |
3073 | * check. (see prepare_charge() also) |
3074 | */ |
3075 | if (PageAnon(used)) |
3076 | mem_cgroup_uncharge_page(used); |
3077 | /* |
3078 | * At migration, we may charge account against cgroup which has no |
3079 | * tasks. |
3080 | * So, rmdir()->pre_destroy() can be called while we do this charge. |
3081 | * In that case, we need to call pre_destroy() again. check it here. |
3082 | */ |
3083 | cgroup_release_and_wakeup_rmdir(&mem->css); |
3084 | } |
3085 | |
3086 | /* |
3087 | * A call to try to shrink memory usage on charge failure at shmem's swapin. |
3088 | * Calling hierarchical_reclaim is not enough because we should update |
3089 | * last_oom_jiffies to prevent pagefault_out_of_memory from invoking global OOM. |
3090 | * Moreover considering hierarchy, we should reclaim from the mem_over_limit, |
3091 | * not from the memcg which this page would be charged to. |
3092 | * try_charge_swapin does all of these works properly. |
3093 | */ |
3094 | int mem_cgroup_shmem_charge_fallback(struct page *page, |
3095 | struct mm_struct *mm, |
3096 | gfp_t gfp_mask) |
3097 | { |
3098 | struct mem_cgroup *mem; |
3099 | int ret; |
3100 | |
3101 | if (mem_cgroup_disabled()) |
3102 | return 0; |
3103 | |
3104 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); |
3105 | if (!ret) |
3106 | mem_cgroup_cancel_charge_swapin(mem); /* it does !mem check */ |
3107 | |
3108 | return ret; |
3109 | } |
3110 | |
3111 | #ifdef CONFIG_DEBUG_VM |
3112 | static struct page_cgroup *lookup_page_cgroup_used(struct page *page) |
3113 | { |
3114 | struct page_cgroup *pc; |
3115 | |
3116 | pc = lookup_page_cgroup(page); |
3117 | if (likely(pc) && PageCgroupUsed(pc)) |
3118 | return pc; |
3119 | return NULL; |
3120 | } |
3121 | |
3122 | bool mem_cgroup_bad_page_check(struct page *page) |
3123 | { |
3124 | if (mem_cgroup_disabled()) |
3125 | return false; |
3126 | |
3127 | return lookup_page_cgroup_used(page) != NULL; |
3128 | } |
3129 | |
3130 | void mem_cgroup_print_bad_page(struct page *page) |
3131 | { |
3132 | struct page_cgroup *pc; |
3133 | |
3134 | pc = lookup_page_cgroup_used(page); |
3135 | if (pc) { |
3136 | int ret = -1; |
3137 | char *path; |
3138 | |
3139 | printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p", |
3140 | pc, pc->flags, pc->mem_cgroup); |
3141 | |
3142 | path = kmalloc(PATH_MAX, GFP_KERNEL); |
3143 | if (path) { |
3144 | rcu_read_lock(); |
3145 | ret = cgroup_path(pc->mem_cgroup->css.cgroup, |
3146 | path, PATH_MAX); |
3147 | rcu_read_unlock(); |
3148 | } |
3149 | |
3150 | printk(KERN_CONT "(%s)\n", |
3151 | (ret < 0) ? "cannot get the path" : path); |
3152 | kfree(path); |
3153 | } |
3154 | } |
3155 | #endif |
3156 | |
3157 | static DEFINE_MUTEX(set_limit_mutex); |
3158 | |
3159 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
3160 | unsigned long long val) |
3161 | { |
3162 | int retry_count; |
3163 | u64 memswlimit, memlimit; |
3164 | int ret = 0; |
3165 | int children = mem_cgroup_count_children(memcg); |
3166 | u64 curusage, oldusage; |
3167 | int enlarge; |
3168 | |
3169 | /* |
3170 | * For keeping hierarchical_reclaim simple, how long we should retry |
3171 | * is depends on callers. We set our retry-count to be function |
3172 | * of # of children which we should visit in this loop. |
3173 | */ |
3174 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; |
3175 | |
3176 | oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); |
3177 | |
3178 | enlarge = 0; |
3179 | while (retry_count) { |
3180 | if (signal_pending(current)) { |
3181 | ret = -EINTR; |
3182 | break; |
3183 | } |
3184 | /* |
3185 | * Rather than hide all in some function, I do this in |
3186 | * open coded manner. You see what this really does. |
3187 | * We have to guarantee mem->res.limit < mem->memsw.limit. |
3188 | */ |
3189 | mutex_lock(&set_limit_mutex); |
3190 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
3191 | if (memswlimit < val) { |
3192 | ret = -EINVAL; |
3193 | mutex_unlock(&set_limit_mutex); |
3194 | break; |
3195 | } |
3196 | |
3197 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); |
3198 | if (memlimit < val) |
3199 | enlarge = 1; |
3200 | |
3201 | ret = res_counter_set_limit(&memcg->res, val); |
3202 | if (!ret) { |
3203 | if (memswlimit == val) |
3204 | memcg->memsw_is_minimum = true; |
3205 | else |
3206 | memcg->memsw_is_minimum = false; |
3207 | } |
3208 | mutex_unlock(&set_limit_mutex); |
3209 | |
3210 | if (!ret) |
3211 | break; |
3212 | |
3213 | mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, |
3214 | MEM_CGROUP_RECLAIM_SHRINK); |
3215 | curusage = res_counter_read_u64(&memcg->res, RES_USAGE); |
3216 | /* Usage is reduced ? */ |
3217 | if (curusage >= oldusage) |
3218 | retry_count--; |
3219 | else |
3220 | oldusage = curusage; |
3221 | } |
3222 | if (!ret && enlarge) |
3223 | memcg_oom_recover(memcg); |
3224 | |
3225 | return ret; |
3226 | } |
3227 | |
3228 | static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, |
3229 | unsigned long long val) |
3230 | { |
3231 | int retry_count; |
3232 | u64 memlimit, memswlimit, oldusage, curusage; |
3233 | int children = mem_cgroup_count_children(memcg); |
3234 | int ret = -EBUSY; |
3235 | int enlarge = 0; |
3236 | |
3237 | /* see mem_cgroup_resize_res_limit */ |
3238 | retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; |
3239 | oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); |
3240 | while (retry_count) { |
3241 | if (signal_pending(current)) { |
3242 | ret = -EINTR; |
3243 | break; |
3244 | } |
3245 | /* |
3246 | * Rather than hide all in some function, I do this in |
3247 | * open coded manner. You see what this really does. |
3248 | * We have to guarantee mem->res.limit < mem->memsw.limit. |
3249 | */ |
3250 | mutex_lock(&set_limit_mutex); |
3251 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); |
3252 | if (memlimit > val) { |
3253 | ret = -EINVAL; |
3254 | mutex_unlock(&set_limit_mutex); |
3255 | break; |
3256 | } |
3257 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
3258 | if (memswlimit < val) |
3259 | enlarge = 1; |
3260 | ret = res_counter_set_limit(&memcg->memsw, val); |
3261 | if (!ret) { |
3262 | if (memlimit == val) |
3263 | memcg->memsw_is_minimum = true; |
3264 | else |
3265 | memcg->memsw_is_minimum = false; |
3266 | } |
3267 | mutex_unlock(&set_limit_mutex); |
3268 | |
3269 | if (!ret) |
3270 | break; |
3271 | |
3272 | mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, |
3273 | MEM_CGROUP_RECLAIM_NOSWAP | |
3274 | MEM_CGROUP_RECLAIM_SHRINK); |
3275 | curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); |
3276 | /* Usage is reduced ? */ |
3277 | if (curusage >= oldusage) |
3278 | retry_count--; |
3279 | else |
3280 | oldusage = curusage; |
3281 | } |
3282 | if (!ret && enlarge) |
3283 | memcg_oom_recover(memcg); |
3284 | return ret; |
3285 | } |
3286 | |
3287 | unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, |
3288 | gfp_t gfp_mask) |
3289 | { |
3290 | unsigned long nr_reclaimed = 0; |
3291 | struct mem_cgroup_per_zone *mz, *next_mz = NULL; |
3292 | unsigned long reclaimed; |
3293 | int loop = 0; |
3294 | struct mem_cgroup_tree_per_zone *mctz; |
3295 | unsigned long long excess; |
3296 | |
3297 | if (order > 0) |
3298 | return 0; |
3299 | |
3300 | mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone)); |
3301 | /* |
3302 | * This loop can run a while, specially if mem_cgroup's continuously |
3303 | * keep exceeding their soft limit and putting the system under |
3304 | * pressure |
3305 | */ |
3306 | do { |
3307 | if (next_mz) |
3308 | mz = next_mz; |
3309 | else |
3310 | mz = mem_cgroup_largest_soft_limit_node(mctz); |
3311 | if (!mz) |
3312 | break; |
3313 | |
3314 | reclaimed = mem_cgroup_hierarchical_reclaim(mz->mem, zone, |
3315 | gfp_mask, |
3316 | MEM_CGROUP_RECLAIM_SOFT); |
3317 | nr_reclaimed += reclaimed; |
3318 | spin_lock(&mctz->lock); |
3319 | |
3320 | /* |
3321 | * If we failed to reclaim anything from this memory cgroup |
3322 | * it is time to move on to the next cgroup |
3323 | */ |
3324 | next_mz = NULL; |
3325 | if (!reclaimed) { |
3326 | do { |
3327 | /* |
3328 | * Loop until we find yet another one. |
3329 | * |
3330 | * By the time we get the soft_limit lock |
3331 | * again, someone might have aded the |
3332 | * group back on the RB tree. Iterate to |
3333 | * make sure we get a different mem. |
3334 | * mem_cgroup_largest_soft_limit_node returns |
3335 | * NULL if no other cgroup is present on |
3336 | * the tree |
3337 | */ |
3338 | next_mz = |
3339 | __mem_cgroup_largest_soft_limit_node(mctz); |
3340 | if (next_mz == mz) { |
3341 | css_put(&next_mz->mem->css); |
3342 | next_mz = NULL; |
3343 | } else /* next_mz == NULL or other memcg */ |
3344 | break; |
3345 | } while (1); |
3346 | } |
3347 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); |
3348 | excess = res_counter_soft_limit_excess(&mz->mem->res); |
3349 | /* |
3350 | * One school of thought says that we should not add |
3351 | * back the node to the tree if reclaim returns 0. |
3352 | * But our reclaim could return 0, simply because due |
3353 | * to priority we are exposing a smaller subset of |
3354 | * memory to reclaim from. Consider this as a longer |
3355 | * term TODO. |
3356 | */ |
3357 | /* If excess == 0, no tree ops */ |
3358 | __mem_cgroup_insert_exceeded(mz->mem, mz, mctz, excess); |
3359 | spin_unlock(&mctz->lock); |
3360 | css_put(&mz->mem->css); |
3361 | loop++; |
3362 | /* |
3363 | * Could not reclaim anything and there are no more |
3364 | * mem cgroups to try or we seem to be looping without |
3365 | * reclaiming anything. |
3366 | */ |
3367 | if (!nr_reclaimed && |
3368 | (next_mz == NULL || |
3369 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) |
3370 | break; |
3371 | } while (!nr_reclaimed); |
3372 | if (next_mz) |
3373 | css_put(&next_mz->mem->css); |
3374 | return nr_reclaimed; |
3375 | } |
3376 | |
3377 | /* |
3378 | * This routine traverse page_cgroup in given list and drop them all. |
3379 | * *And* this routine doesn't reclaim page itself, just removes page_cgroup. |
3380 | */ |
3381 | static int mem_cgroup_force_empty_list(struct mem_cgroup *mem, |
3382 | int node, int zid, enum lru_list lru) |
3383 | { |
3384 | struct zone *zone; |
3385 | struct mem_cgroup_per_zone *mz; |
3386 | struct page_cgroup *pc, *busy; |
3387 | unsigned long flags, loop; |
3388 | struct list_head *list; |
3389 | int ret = 0; |
3390 | |
3391 | zone = &NODE_DATA(node)->node_zones[zid]; |
3392 | mz = mem_cgroup_zoneinfo(mem, node, zid); |
3393 | list = &mz->lists[lru]; |
3394 | |
3395 | loop = MEM_CGROUP_ZSTAT(mz, lru); |
3396 | /* give some margin against EBUSY etc...*/ |
3397 | loop += 256; |
3398 | busy = NULL; |
3399 | while (loop--) { |
3400 | struct page *page; |
3401 | |
3402 | ret = 0; |
3403 | spin_lock_irqsave(&zone->lru_lock, flags); |
3404 | if (list_empty(list)) { |
3405 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
3406 | break; |
3407 | } |
3408 | pc = list_entry(list->prev, struct page_cgroup, lru); |
3409 | if (busy == pc) { |
3410 | list_move(&pc->lru, list); |
3411 | busy = NULL; |
3412 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
3413 | continue; |
3414 | } |
3415 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
3416 | |
3417 | page = lookup_cgroup_page(pc); |
3418 | |
3419 | ret = mem_cgroup_move_parent(page, pc, mem, GFP_KERNEL); |
3420 | if (ret == -ENOMEM) |
3421 | break; |
3422 | |
3423 | if (ret == -EBUSY || ret == -EINVAL) { |
3424 | /* found lock contention or "pc" is obsolete. */ |
3425 | busy = pc; |
3426 | cond_resched(); |
3427 | } else |
3428 | busy = NULL; |
3429 | } |
3430 | |
3431 | if (!ret && !list_empty(list)) |
3432 | return -EBUSY; |
3433 | return ret; |
3434 | } |
3435 | |
3436 | /* |
3437 | * make mem_cgroup's charge to be 0 if there is no task. |
3438 | * This enables deleting this mem_cgroup. |
3439 | */ |
3440 | static int mem_cgroup_force_empty(struct mem_cgroup *mem, bool free_all) |
3441 | { |
3442 | int ret; |
3443 | int node, zid, shrink; |
3444 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; |
3445 | struct cgroup *cgrp = mem->css.cgroup; |
3446 | |
3447 | css_get(&mem->css); |
3448 | |
3449 | shrink = 0; |
3450 | /* should free all ? */ |
3451 | if (free_all) |
3452 | goto try_to_free; |
3453 | move_account: |
3454 | do { |
3455 | ret = -EBUSY; |
3456 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children)) |
3457 | goto out; |
3458 | ret = -EINTR; |
3459 | if (signal_pending(current)) |
3460 | goto out; |
3461 | /* This is for making all *used* pages to be on LRU. */ |
3462 | lru_add_drain_all(); |
3463 | drain_all_stock_sync(); |
3464 | ret = 0; |
3465 | mem_cgroup_start_move(mem); |
3466 | for_each_node_state(node, N_HIGH_MEMORY) { |
3467 | for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { |
3468 | enum lru_list l; |
3469 | for_each_lru(l) { |
3470 | ret = mem_cgroup_force_empty_list(mem, |
3471 | node, zid, l); |
3472 | if (ret) |
3473 | break; |
3474 | } |
3475 | } |
3476 | if (ret) |
3477 | break; |
3478 | } |
3479 | mem_cgroup_end_move(mem); |
3480 | memcg_oom_recover(mem); |
3481 | /* it seems parent cgroup doesn't have enough mem */ |
3482 | if (ret == -ENOMEM) |
3483 | goto try_to_free; |
3484 | cond_resched(); |
3485 | /* "ret" should also be checked to ensure all lists are empty. */ |
3486 | } while (mem->res.usage > 0 || ret); |
3487 | out: |
3488 | css_put(&mem->css); |
3489 | return ret; |
3490 | |
3491 | try_to_free: |
3492 | /* returns EBUSY if there is a task or if we come here twice. */ |
3493 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) { |
3494 | ret = -EBUSY; |
3495 | goto out; |
3496 | } |
3497 | /* we call try-to-free pages for make this cgroup empty */ |
3498 | lru_add_drain_all(); |
3499 | /* try to free all pages in this cgroup */ |
3500 | shrink = 1; |
3501 | while (nr_retries && mem->res.usage > 0) { |
3502 | int progress; |
3503 | |
3504 | if (signal_pending(current)) { |
3505 | ret = -EINTR; |
3506 | goto out; |
3507 | } |
3508 | progress = try_to_free_mem_cgroup_pages(mem, GFP_KERNEL, |
3509 | false, get_swappiness(mem)); |
3510 | if (!progress) { |
3511 | nr_retries--; |
3512 | /* maybe some writeback is necessary */ |
3513 | congestion_wait(BLK_RW_ASYNC, HZ/10); |
3514 | } |
3515 | |
3516 | } |
3517 | lru_add_drain(); |
3518 | /* try move_account...there may be some *locked* pages. */ |
3519 | goto move_account; |
3520 | } |
3521 | |
3522 | int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event) |
3523 | { |
3524 | return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true); |
3525 | } |
3526 | |
3527 | |
3528 | static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft) |
3529 | { |
3530 | return mem_cgroup_from_cont(cont)->use_hierarchy; |
3531 | } |
3532 | |
3533 | static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft, |
3534 | u64 val) |
3535 | { |
3536 | int retval = 0; |
3537 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
3538 | struct cgroup *parent = cont->parent; |
3539 | struct mem_cgroup *parent_mem = NULL; |
3540 | |
3541 | if (parent) |
3542 | parent_mem = mem_cgroup_from_cont(parent); |
3543 | |
3544 | cgroup_lock(); |
3545 | /* |
3546 | * If parent's use_hierarchy is set, we can't make any modifications |
3547 | * in the child subtrees. If it is unset, then the change can |
3548 | * occur, provided the current cgroup has no children. |
3549 | * |
3550 | * For the root cgroup, parent_mem is NULL, we allow value to be |
3551 | * set if there are no children. |
3552 | */ |
3553 | if ((!parent_mem || !parent_mem->use_hierarchy) && |
3554 | (val == 1 || val == 0)) { |
3555 | if (list_empty(&cont->children)) |
3556 | mem->use_hierarchy = val; |
3557 | else |
3558 | retval = -EBUSY; |
3559 | } else |
3560 | retval = -EINVAL; |
3561 | cgroup_unlock(); |
3562 | |
3563 | return retval; |
3564 | } |
3565 | |
3566 | |
3567 | static unsigned long mem_cgroup_recursive_stat(struct mem_cgroup *mem, |
3568 | enum mem_cgroup_stat_index idx) |
3569 | { |
3570 | struct mem_cgroup *iter; |
3571 | long val = 0; |
3572 | |
3573 | /* Per-cpu values can be negative, use a signed accumulator */ |
3574 | for_each_mem_cgroup_tree(iter, mem) |
3575 | val += mem_cgroup_read_stat(iter, idx); |
3576 | |
3577 | if (val < 0) /* race ? */ |
3578 | val = 0; |
3579 | return val; |
3580 | } |
3581 | |
3582 | static inline u64 mem_cgroup_usage(struct mem_cgroup *mem, bool swap) |
3583 | { |
3584 | u64 val; |
3585 | |
3586 | if (!mem_cgroup_is_root(mem)) { |
3587 | if (!swap) |
3588 | return res_counter_read_u64(&mem->res, RES_USAGE); |
3589 | else |
3590 | return res_counter_read_u64(&mem->memsw, RES_USAGE); |
3591 | } |
3592 | |
3593 | val = mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_CACHE); |
3594 | val += mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_RSS); |
3595 | |
3596 | if (swap) |
3597 | val += mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_SWAPOUT); |
3598 | |
3599 | return val << PAGE_SHIFT; |
3600 | } |
3601 | |
3602 | static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) |
3603 | { |
3604 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
3605 | u64 val; |
3606 | int type, name; |
3607 | |
3608 | type = MEMFILE_TYPE(cft->private); |
3609 | name = MEMFILE_ATTR(cft->private); |
3610 | switch (type) { |
3611 | case _MEM: |
3612 | if (name == RES_USAGE) |
3613 | val = mem_cgroup_usage(mem, false); |
3614 | else |
3615 | val = res_counter_read_u64(&mem->res, name); |
3616 | break; |
3617 | case _MEMSWAP: |
3618 | if (name == RES_USAGE) |
3619 | val = mem_cgroup_usage(mem, true); |
3620 | else |
3621 | val = res_counter_read_u64(&mem->memsw, name); |
3622 | break; |
3623 | default: |
3624 | BUG(); |
3625 | break; |
3626 | } |
3627 | return val; |
3628 | } |
3629 | /* |
3630 | * The user of this function is... |
3631 | * RES_LIMIT. |
3632 | */ |
3633 | static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, |
3634 | const char *buffer) |
3635 | { |
3636 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
3637 | int type, name; |
3638 | unsigned long long val; |
3639 | int ret; |
3640 | |
3641 | type = MEMFILE_TYPE(cft->private); |
3642 | name = MEMFILE_ATTR(cft->private); |
3643 | switch (name) { |
3644 | case RES_LIMIT: |
3645 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
3646 | ret = -EINVAL; |
3647 | break; |
3648 | } |
3649 | /* This function does all necessary parse...reuse it */ |
3650 | ret = res_counter_memparse_write_strategy(buffer, &val); |
3651 | if (ret) |
3652 | break; |
3653 | if (type == _MEM) |
3654 | ret = mem_cgroup_resize_limit(memcg, val); |
3655 | else |
3656 | ret = mem_cgroup_resize_memsw_limit(memcg, val); |
3657 | break; |
3658 | case RES_SOFT_LIMIT: |
3659 | ret = res_counter_memparse_write_strategy(buffer, &val); |
3660 | if (ret) |
3661 | break; |
3662 | /* |
3663 | * For memsw, soft limits are hard to implement in terms |
3664 | * of semantics, for now, we support soft limits for |
3665 | * control without swap |
3666 | */ |
3667 | if (type == _MEM) |
3668 | ret = res_counter_set_soft_limit(&memcg->res, val); |
3669 | else |
3670 | ret = -EINVAL; |
3671 | break; |
3672 | default: |
3673 | ret = -EINVAL; /* should be BUG() ? */ |
3674 | break; |
3675 | } |
3676 | return ret; |
3677 | } |
3678 | |
3679 | static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, |
3680 | unsigned long long *mem_limit, unsigned long long *memsw_limit) |
3681 | { |
3682 | struct cgroup *cgroup; |
3683 | unsigned long long min_limit, min_memsw_limit, tmp; |
3684 | |
3685 | min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); |
3686 | min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
3687 | cgroup = memcg->css.cgroup; |
3688 | if (!memcg->use_hierarchy) |
3689 | goto out; |
3690 | |
3691 | while (cgroup->parent) { |
3692 | cgroup = cgroup->parent; |
3693 | memcg = mem_cgroup_from_cont(cgroup); |
3694 | if (!memcg->use_hierarchy) |
3695 | break; |
3696 | tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); |
3697 | min_limit = min(min_limit, tmp); |
3698 | tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
3699 | min_memsw_limit = min(min_memsw_limit, tmp); |
3700 | } |
3701 | out: |
3702 | *mem_limit = min_limit; |
3703 | *memsw_limit = min_memsw_limit; |
3704 | return; |
3705 | } |
3706 | |
3707 | static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) |
3708 | { |
3709 | struct mem_cgroup *mem; |
3710 | int type, name; |
3711 | |
3712 | mem = mem_cgroup_from_cont(cont); |
3713 | type = MEMFILE_TYPE(event); |
3714 | name = MEMFILE_ATTR(event); |
3715 | switch (name) { |
3716 | case RES_MAX_USAGE: |
3717 | if (type == _MEM) |
3718 | res_counter_reset_max(&mem->res); |
3719 | else |
3720 | res_counter_reset_max(&mem->memsw); |
3721 | break; |
3722 | case RES_FAILCNT: |
3723 | if (type == _MEM) |
3724 | res_counter_reset_failcnt(&mem->res); |
3725 | else |
3726 | res_counter_reset_failcnt(&mem->memsw); |
3727 | break; |
3728 | } |
3729 | |
3730 | return 0; |
3731 | } |
3732 | |
3733 | static u64 mem_cgroup_move_charge_read(struct cgroup *cgrp, |
3734 | struct cftype *cft) |
3735 | { |
3736 | return mem_cgroup_from_cont(cgrp)->move_charge_at_immigrate; |
3737 | } |
3738 | |
3739 | #ifdef CONFIG_MMU |
3740 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, |
3741 | struct cftype *cft, u64 val) |
3742 | { |
3743 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); |
3744 | |
3745 | if (val >= (1 << NR_MOVE_TYPE)) |
3746 | return -EINVAL; |
3747 | /* |
3748 | * We check this value several times in both in can_attach() and |
3749 | * attach(), so we need cgroup lock to prevent this value from being |
3750 | * inconsistent. |
3751 | */ |
3752 | cgroup_lock(); |
3753 | mem->move_charge_at_immigrate = val; |
3754 | cgroup_unlock(); |
3755 | |
3756 | return 0; |
3757 | } |
3758 | #else |
3759 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, |
3760 | struct cftype *cft, u64 val) |
3761 | { |
3762 | return -ENOSYS; |
3763 | } |
3764 | #endif |
3765 | |
3766 | |
3767 | /* For read statistics */ |
3768 | enum { |
3769 | MCS_CACHE, |
3770 | MCS_RSS, |
3771 | MCS_FILE_MAPPED, |
3772 | MCS_PGPGIN, |
3773 | MCS_PGPGOUT, |
3774 | MCS_SWAP, |
3775 | MCS_INACTIVE_ANON, |
3776 | MCS_ACTIVE_ANON, |
3777 | MCS_INACTIVE_FILE, |
3778 | MCS_ACTIVE_FILE, |
3779 | MCS_UNEVICTABLE, |
3780 | NR_MCS_STAT, |
3781 | }; |
3782 | |
3783 | struct mcs_total_stat { |
3784 | s64 stat[NR_MCS_STAT]; |
3785 | }; |
3786 | |
3787 | struct { |
3788 | char *local_name; |
3789 | char *total_name; |
3790 | } memcg_stat_strings[NR_MCS_STAT] = { |
3791 | {"cache", "total_cache"}, |
3792 | {"rss", "total_rss"}, |
3793 | {"mapped_file", "total_mapped_file"}, |
3794 | {"pgpgin", "total_pgpgin"}, |
3795 | {"pgpgout", "total_pgpgout"}, |
3796 | {"swap", "total_swap"}, |
3797 | {"inactive_anon", "total_inactive_anon"}, |
3798 | {"active_anon", "total_active_anon"}, |
3799 | {"inactive_file", "total_inactive_file"}, |
3800 | {"active_file", "total_active_file"}, |
3801 | {"unevictable", "total_unevictable"} |
3802 | }; |
3803 | |
3804 | |
3805 | static void |
3806 | mem_cgroup_get_local_stat(struct mem_cgroup *mem, struct mcs_total_stat *s) |
3807 | { |
3808 | s64 val; |
3809 | |
3810 | /* per cpu stat */ |
3811 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_CACHE); |
3812 | s->stat[MCS_CACHE] += val * PAGE_SIZE; |
3813 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_RSS); |
3814 | s->stat[MCS_RSS] += val * PAGE_SIZE; |
3815 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_FILE_MAPPED); |
3816 | s->stat[MCS_FILE_MAPPED] += val * PAGE_SIZE; |
3817 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGPGIN); |
3818 | s->stat[MCS_PGPGIN] += val; |
3819 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGPGOUT); |
3820 | s->stat[MCS_PGPGOUT] += val; |
3821 | if (do_swap_account) { |
3822 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_SWAPOUT); |
3823 | s->stat[MCS_SWAP] += val * PAGE_SIZE; |
3824 | } |
3825 | |
3826 | /* per zone stat */ |
3827 | val = mem_cgroup_get_local_zonestat(mem, LRU_INACTIVE_ANON); |
3828 | s->stat[MCS_INACTIVE_ANON] += val * PAGE_SIZE; |
3829 | val = mem_cgroup_get_local_zonestat(mem, LRU_ACTIVE_ANON); |
3830 | s->stat[MCS_ACTIVE_ANON] += val * PAGE_SIZE; |
3831 | val = mem_cgroup_get_local_zonestat(mem, LRU_INACTIVE_FILE); |
3832 | s->stat[MCS_INACTIVE_FILE] += val * PAGE_SIZE; |
3833 | val = mem_cgroup_get_local_zonestat(mem, LRU_ACTIVE_FILE); |
3834 | s->stat[MCS_ACTIVE_FILE] += val * PAGE_SIZE; |
3835 | val = mem_cgroup_get_local_zonestat(mem, LRU_UNEVICTABLE); |
3836 | s->stat[MCS_UNEVICTABLE] += val * PAGE_SIZE; |
3837 | } |
3838 | |
3839 | static void |
3840 | mem_cgroup_get_total_stat(struct mem_cgroup *mem, struct mcs_total_stat *s) |
3841 | { |
3842 | struct mem_cgroup *iter; |
3843 | |
3844 | for_each_mem_cgroup_tree(iter, mem) |
3845 | mem_cgroup_get_local_stat(iter, s); |
3846 | } |
3847 | |
3848 | static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, |
3849 | struct cgroup_map_cb *cb) |
3850 | { |
3851 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); |
3852 | struct mcs_total_stat mystat; |
3853 | int i; |
3854 | |
3855 | memset(&mystat, 0, sizeof(mystat)); |
3856 | mem_cgroup_get_local_stat(mem_cont, &mystat); |
3857 | |
3858 | for (i = 0; i < NR_MCS_STAT; i++) { |
3859 | if (i == MCS_SWAP && !do_swap_account) |
3860 | continue; |
3861 | cb->fill(cb, memcg_stat_strings[i].local_name, mystat.stat[i]); |
3862 | } |
3863 | |
3864 | /* Hierarchical information */ |
3865 | { |
3866 | unsigned long long limit, memsw_limit; |
3867 | memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit); |
3868 | cb->fill(cb, "hierarchical_memory_limit", limit); |
3869 | if (do_swap_account) |
3870 | cb->fill(cb, "hierarchical_memsw_limit", memsw_limit); |
3871 | } |
3872 | |
3873 | memset(&mystat, 0, sizeof(mystat)); |
3874 | mem_cgroup_get_total_stat(mem_cont, &mystat); |
3875 | for (i = 0; i < NR_MCS_STAT; i++) { |
3876 | if (i == MCS_SWAP && !do_swap_account) |
3877 | continue; |
3878 | cb->fill(cb, memcg_stat_strings[i].total_name, mystat.stat[i]); |
3879 | } |
3880 | |
3881 | #ifdef CONFIG_DEBUG_VM |
3882 | cb->fill(cb, "inactive_ratio", calc_inactive_ratio(mem_cont, NULL)); |
3883 | |
3884 | { |
3885 | int nid, zid; |
3886 | struct mem_cgroup_per_zone *mz; |
3887 | unsigned long recent_rotated[2] = {0, 0}; |
3888 | unsigned long recent_scanned[2] = {0, 0}; |
3889 | |
3890 | for_each_online_node(nid) |
3891 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { |
3892 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); |
3893 | |
3894 | recent_rotated[0] += |
3895 | mz->reclaim_stat.recent_rotated[0]; |
3896 | recent_rotated[1] += |
3897 | mz->reclaim_stat.recent_rotated[1]; |
3898 | recent_scanned[0] += |
3899 | mz->reclaim_stat.recent_scanned[0]; |
3900 | recent_scanned[1] += |
3901 | mz->reclaim_stat.recent_scanned[1]; |
3902 | } |
3903 | cb->fill(cb, "recent_rotated_anon", recent_rotated[0]); |
3904 | cb->fill(cb, "recent_rotated_file", recent_rotated[1]); |
3905 | cb->fill(cb, "recent_scanned_anon", recent_scanned[0]); |
3906 | cb->fill(cb, "recent_scanned_file", recent_scanned[1]); |
3907 | } |
3908 | #endif |
3909 | |
3910 | return 0; |
3911 | } |
3912 | |
3913 | static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft) |
3914 | { |
3915 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
3916 | |
3917 | return get_swappiness(memcg); |
3918 | } |
3919 | |
3920 | static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, |
3921 | u64 val) |
3922 | { |
3923 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
3924 | struct mem_cgroup *parent; |
3925 | |
3926 | if (val > 100) |
3927 | return -EINVAL; |
3928 | |
3929 | if (cgrp->parent == NULL) |
3930 | return -EINVAL; |
3931 | |
3932 | parent = mem_cgroup_from_cont(cgrp->parent); |
3933 | |
3934 | cgroup_lock(); |
3935 | |
3936 | /* If under hierarchy, only empty-root can set this value */ |
3937 | if ((parent->use_hierarchy) || |
3938 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
3939 | cgroup_unlock(); |
3940 | return -EINVAL; |
3941 | } |
3942 | |
3943 | memcg->swappiness = val; |
3944 | |
3945 | cgroup_unlock(); |
3946 | |
3947 | return 0; |
3948 | } |
3949 | |
3950 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
3951 | { |
3952 | struct mem_cgroup_threshold_ary *t; |
3953 | u64 usage; |
3954 | int i; |
3955 | |
3956 | rcu_read_lock(); |
3957 | if (!swap) |
3958 | t = rcu_dereference(memcg->thresholds.primary); |
3959 | else |
3960 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
3961 | |
3962 | if (!t) |
3963 | goto unlock; |
3964 | |
3965 | usage = mem_cgroup_usage(memcg, swap); |
3966 | |
3967 | /* |
3968 | * current_threshold points to threshold just below usage. |
3969 | * If it's not true, a threshold was crossed after last |
3970 | * call of __mem_cgroup_threshold(). |
3971 | */ |
3972 | i = t->current_threshold; |
3973 | |
3974 | /* |
3975 | * Iterate backward over array of thresholds starting from |
3976 | * current_threshold and check if a threshold is crossed. |
3977 | * If none of thresholds below usage is crossed, we read |
3978 | * only one element of the array here. |
3979 | */ |
3980 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) |
3981 | eventfd_signal(t->entries[i].eventfd, 1); |
3982 | |
3983 | /* i = current_threshold + 1 */ |
3984 | i++; |
3985 | |
3986 | /* |
3987 | * Iterate forward over array of thresholds starting from |
3988 | * current_threshold+1 and check if a threshold is crossed. |
3989 | * If none of thresholds above usage is crossed, we read |
3990 | * only one element of the array here. |
3991 | */ |
3992 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) |
3993 | eventfd_signal(t->entries[i].eventfd, 1); |
3994 | |
3995 | /* Update current_threshold */ |
3996 | t->current_threshold = i - 1; |
3997 | unlock: |
3998 | rcu_read_unlock(); |
3999 | } |
4000 | |
4001 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) |
4002 | { |
4003 | while (memcg) { |
4004 | __mem_cgroup_threshold(memcg, false); |
4005 | if (do_swap_account) |
4006 | __mem_cgroup_threshold(memcg, true); |
4007 | |
4008 | memcg = parent_mem_cgroup(memcg); |
4009 | } |
4010 | } |
4011 | |
4012 | static int compare_thresholds(const void *a, const void *b) |
4013 | { |
4014 | const struct mem_cgroup_threshold *_a = a; |
4015 | const struct mem_cgroup_threshold *_b = b; |
4016 | |
4017 | return _a->threshold - _b->threshold; |
4018 | } |
4019 | |
4020 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *mem) |
4021 | { |
4022 | struct mem_cgroup_eventfd_list *ev; |
4023 | |
4024 | list_for_each_entry(ev, &mem->oom_notify, list) |
4025 | eventfd_signal(ev->eventfd, 1); |
4026 | return 0; |
4027 | } |
4028 | |
4029 | static void mem_cgroup_oom_notify(struct mem_cgroup *mem) |
4030 | { |
4031 | struct mem_cgroup *iter; |
4032 | |
4033 | for_each_mem_cgroup_tree(iter, mem) |
4034 | mem_cgroup_oom_notify_cb(iter); |
4035 | } |
4036 | |
4037 | static int mem_cgroup_usage_register_event(struct cgroup *cgrp, |
4038 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) |
4039 | { |
4040 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
4041 | struct mem_cgroup_thresholds *thresholds; |
4042 | struct mem_cgroup_threshold_ary *new; |
4043 | int type = MEMFILE_TYPE(cft->private); |
4044 | u64 threshold, usage; |
4045 | int i, size, ret; |
4046 | |
4047 | ret = res_counter_memparse_write_strategy(args, &threshold); |
4048 | if (ret) |
4049 | return ret; |
4050 | |
4051 | mutex_lock(&memcg->thresholds_lock); |
4052 | |
4053 | if (type == _MEM) |
4054 | thresholds = &memcg->thresholds; |
4055 | else if (type == _MEMSWAP) |
4056 | thresholds = &memcg->memsw_thresholds; |
4057 | else |
4058 | BUG(); |
4059 | |
4060 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); |
4061 | |
4062 | /* Check if a threshold crossed before adding a new one */ |
4063 | if (thresholds->primary) |
4064 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4065 | |
4066 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
4067 | |
4068 | /* Allocate memory for new array of thresholds */ |
4069 | new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold), |
4070 | GFP_KERNEL); |
4071 | if (!new) { |
4072 | ret = -ENOMEM; |
4073 | goto unlock; |
4074 | } |
4075 | new->size = size; |
4076 | |
4077 | /* Copy thresholds (if any) to new array */ |
4078 | if (thresholds->primary) { |
4079 | memcpy(new->entries, thresholds->primary->entries, (size - 1) * |
4080 | sizeof(struct mem_cgroup_threshold)); |
4081 | } |
4082 | |
4083 | /* Add new threshold */ |
4084 | new->entries[size - 1].eventfd = eventfd; |
4085 | new->entries[size - 1].threshold = threshold; |
4086 | |
4087 | /* Sort thresholds. Registering of new threshold isn't time-critical */ |
4088 | sort(new->entries, size, sizeof(struct mem_cgroup_threshold), |
4089 | compare_thresholds, NULL); |
4090 | |
4091 | /* Find current threshold */ |
4092 | new->current_threshold = -1; |
4093 | for (i = 0; i < size; i++) { |
4094 | if (new->entries[i].threshold < usage) { |
4095 | /* |
4096 | * new->current_threshold will not be used until |
4097 | * rcu_assign_pointer(), so it's safe to increment |
4098 | * it here. |
4099 | */ |
4100 | ++new->current_threshold; |
4101 | } |
4102 | } |
4103 | |
4104 | /* Free old spare buffer and save old primary buffer as spare */ |
4105 | kfree(thresholds->spare); |
4106 | thresholds->spare = thresholds->primary; |
4107 | |
4108 | rcu_assign_pointer(thresholds->primary, new); |
4109 | |
4110 | /* To be sure that nobody uses thresholds */ |
4111 | synchronize_rcu(); |
4112 | |
4113 | unlock: |
4114 | mutex_unlock(&memcg->thresholds_lock); |
4115 | |
4116 | return ret; |
4117 | } |
4118 | |
4119 | static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp, |
4120 | struct cftype *cft, struct eventfd_ctx *eventfd) |
4121 | { |
4122 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
4123 | struct mem_cgroup_thresholds *thresholds; |
4124 | struct mem_cgroup_threshold_ary *new; |
4125 | int type = MEMFILE_TYPE(cft->private); |
4126 | u64 usage; |
4127 | int i, j, size; |
4128 | |
4129 | mutex_lock(&memcg->thresholds_lock); |
4130 | if (type == _MEM) |
4131 | thresholds = &memcg->thresholds; |
4132 | else if (type == _MEMSWAP) |
4133 | thresholds = &memcg->memsw_thresholds; |
4134 | else |
4135 | BUG(); |
4136 | |
4137 | /* |
4138 | * Something went wrong if we trying to unregister a threshold |
4139 | * if we don't have thresholds |
4140 | */ |
4141 | BUG_ON(!thresholds); |
4142 | |
4143 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); |
4144 | |
4145 | /* Check if a threshold crossed before removing */ |
4146 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4147 | |
4148 | /* Calculate new number of threshold */ |
4149 | size = 0; |
4150 | for (i = 0; i < thresholds->primary->size; i++) { |
4151 | if (thresholds->primary->entries[i].eventfd != eventfd) |
4152 | size++; |
4153 | } |
4154 | |
4155 | new = thresholds->spare; |
4156 | |
4157 | /* Set thresholds array to NULL if we don't have thresholds */ |
4158 | if (!size) { |
4159 | kfree(new); |
4160 | new = NULL; |
4161 | goto swap_buffers; |
4162 | } |
4163 | |
4164 | new->size = size; |
4165 | |
4166 | /* Copy thresholds and find current threshold */ |
4167 | new->current_threshold = -1; |
4168 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { |
4169 | if (thresholds->primary->entries[i].eventfd == eventfd) |
4170 | continue; |
4171 | |
4172 | new->entries[j] = thresholds->primary->entries[i]; |
4173 | if (new->entries[j].threshold < usage) { |
4174 | /* |
4175 | * new->current_threshold will not be used |
4176 | * until rcu_assign_pointer(), so it's safe to increment |
4177 | * it here. |
4178 | */ |
4179 | ++new->current_threshold; |
4180 | } |
4181 | j++; |
4182 | } |
4183 | |
4184 | swap_buffers: |
4185 | /* Swap primary and spare array */ |
4186 | thresholds->spare = thresholds->primary; |
4187 | rcu_assign_pointer(thresholds->primary, new); |
4188 | |
4189 | /* To be sure that nobody uses thresholds */ |
4190 | synchronize_rcu(); |
4191 | |
4192 | mutex_unlock(&memcg->thresholds_lock); |
4193 | } |
4194 | |
4195 | static int mem_cgroup_oom_register_event(struct cgroup *cgrp, |
4196 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) |
4197 | { |
4198 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); |
4199 | struct mem_cgroup_eventfd_list *event; |
4200 | int type = MEMFILE_TYPE(cft->private); |
4201 | |
4202 | BUG_ON(type != _OOM_TYPE); |
4203 | event = kmalloc(sizeof(*event), GFP_KERNEL); |
4204 | if (!event) |
4205 | return -ENOMEM; |
4206 | |
4207 | mutex_lock(&memcg_oom_mutex); |
4208 | |
4209 | event->eventfd = eventfd; |
4210 | list_add(&event->list, &memcg->oom_notify); |
4211 | |
4212 | /* already in OOM ? */ |
4213 | if (atomic_read(&memcg->oom_lock)) |
4214 | eventfd_signal(eventfd, 1); |
4215 | mutex_unlock(&memcg_oom_mutex); |
4216 | |
4217 | return 0; |
4218 | } |
4219 | |
4220 | static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp, |
4221 | struct cftype *cft, struct eventfd_ctx *eventfd) |
4222 | { |
4223 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); |
4224 | struct mem_cgroup_eventfd_list *ev, *tmp; |
4225 | int type = MEMFILE_TYPE(cft->private); |
4226 | |
4227 | BUG_ON(type != _OOM_TYPE); |
4228 | |
4229 | mutex_lock(&memcg_oom_mutex); |
4230 | |
4231 | list_for_each_entry_safe(ev, tmp, &mem->oom_notify, list) { |
4232 | if (ev->eventfd == eventfd) { |
4233 | list_del(&ev->list); |
4234 | kfree(ev); |
4235 | } |
4236 | } |
4237 | |
4238 | mutex_unlock(&memcg_oom_mutex); |
4239 | } |
4240 | |
4241 | static int mem_cgroup_oom_control_read(struct cgroup *cgrp, |
4242 | struct cftype *cft, struct cgroup_map_cb *cb) |
4243 | { |
4244 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); |
4245 | |
4246 | cb->fill(cb, "oom_kill_disable", mem->oom_kill_disable); |
4247 | |
4248 | if (atomic_read(&mem->oom_lock)) |
4249 | cb->fill(cb, "under_oom", 1); |
4250 | else |
4251 | cb->fill(cb, "under_oom", 0); |
4252 | return 0; |
4253 | } |
4254 | |
4255 | static int mem_cgroup_oom_control_write(struct cgroup *cgrp, |
4256 | struct cftype *cft, u64 val) |
4257 | { |
4258 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); |
4259 | struct mem_cgroup *parent; |
4260 | |
4261 | /* cannot set to root cgroup and only 0 and 1 are allowed */ |
4262 | if (!cgrp->parent || !((val == 0) || (val == 1))) |
4263 | return -EINVAL; |
4264 | |
4265 | parent = mem_cgroup_from_cont(cgrp->parent); |
4266 | |
4267 | cgroup_lock(); |
4268 | /* oom-kill-disable is a flag for subhierarchy. */ |
4269 | if ((parent->use_hierarchy) || |
4270 | (mem->use_hierarchy && !list_empty(&cgrp->children))) { |
4271 | cgroup_unlock(); |
4272 | return -EINVAL; |
4273 | } |
4274 | mem->oom_kill_disable = val; |
4275 | if (!val) |
4276 | memcg_oom_recover(mem); |
4277 | cgroup_unlock(); |
4278 | return 0; |
4279 | } |
4280 | |
4281 | static struct cftype mem_cgroup_files[] = { |
4282 | { |
4283 | .name = "usage_in_bytes", |
4284 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
4285 | .read_u64 = mem_cgroup_read, |
4286 | .register_event = mem_cgroup_usage_register_event, |
4287 | .unregister_event = mem_cgroup_usage_unregister_event, |
4288 | }, |
4289 | { |
4290 | .name = "max_usage_in_bytes", |
4291 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
4292 | .trigger = mem_cgroup_reset, |
4293 | .read_u64 = mem_cgroup_read, |
4294 | }, |
4295 | { |
4296 | .name = "limit_in_bytes", |
4297 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
4298 | .write_string = mem_cgroup_write, |
4299 | .read_u64 = mem_cgroup_read, |
4300 | }, |
4301 | { |
4302 | .name = "soft_limit_in_bytes", |
4303 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), |
4304 | .write_string = mem_cgroup_write, |
4305 | .read_u64 = mem_cgroup_read, |
4306 | }, |
4307 | { |
4308 | .name = "failcnt", |
4309 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
4310 | .trigger = mem_cgroup_reset, |
4311 | .read_u64 = mem_cgroup_read, |
4312 | }, |
4313 | { |
4314 | .name = "stat", |
4315 | .read_map = mem_control_stat_show, |
4316 | }, |
4317 | { |
4318 | .name = "force_empty", |
4319 | .trigger = mem_cgroup_force_empty_write, |
4320 | }, |
4321 | { |
4322 | .name = "use_hierarchy", |
4323 | .write_u64 = mem_cgroup_hierarchy_write, |
4324 | .read_u64 = mem_cgroup_hierarchy_read, |
4325 | }, |
4326 | { |
4327 | .name = "swappiness", |
4328 | .read_u64 = mem_cgroup_swappiness_read, |
4329 | .write_u64 = mem_cgroup_swappiness_write, |
4330 | }, |
4331 | { |
4332 | .name = "move_charge_at_immigrate", |
4333 | .read_u64 = mem_cgroup_move_charge_read, |
4334 | .write_u64 = mem_cgroup_move_charge_write, |
4335 | }, |
4336 | { |
4337 | .name = "oom_control", |
4338 | .read_map = mem_cgroup_oom_control_read, |
4339 | .write_u64 = mem_cgroup_oom_control_write, |
4340 | .register_event = mem_cgroup_oom_register_event, |
4341 | .unregister_event = mem_cgroup_oom_unregister_event, |
4342 | .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), |
4343 | }, |
4344 | }; |
4345 | |
4346 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4347 | static struct cftype memsw_cgroup_files[] = { |
4348 | { |
4349 | .name = "memsw.usage_in_bytes", |
4350 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), |
4351 | .read_u64 = mem_cgroup_read, |
4352 | .register_event = mem_cgroup_usage_register_event, |
4353 | .unregister_event = mem_cgroup_usage_unregister_event, |
4354 | }, |
4355 | { |
4356 | .name = "memsw.max_usage_in_bytes", |
4357 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), |
4358 | .trigger = mem_cgroup_reset, |
4359 | .read_u64 = mem_cgroup_read, |
4360 | }, |
4361 | { |
4362 | .name = "memsw.limit_in_bytes", |
4363 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), |
4364 | .write_string = mem_cgroup_write, |
4365 | .read_u64 = mem_cgroup_read, |
4366 | }, |
4367 | { |
4368 | .name = "memsw.failcnt", |
4369 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), |
4370 | .trigger = mem_cgroup_reset, |
4371 | .read_u64 = mem_cgroup_read, |
4372 | }, |
4373 | }; |
4374 | |
4375 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) |
4376 | { |
4377 | if (!do_swap_account) |
4378 | return 0; |
4379 | return cgroup_add_files(cont, ss, memsw_cgroup_files, |
4380 | ARRAY_SIZE(memsw_cgroup_files)); |
4381 | }; |
4382 | #else |
4383 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) |
4384 | { |
4385 | return 0; |
4386 | } |
4387 | #endif |
4388 | |
4389 | static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
4390 | { |
4391 | struct mem_cgroup_per_node *pn; |
4392 | struct mem_cgroup_per_zone *mz; |
4393 | enum lru_list l; |
4394 | int zone, tmp = node; |
4395 | /* |
4396 | * This routine is called against possible nodes. |
4397 | * But it's BUG to call kmalloc() against offline node. |
4398 | * |
4399 | * TODO: this routine can waste much memory for nodes which will |
4400 | * never be onlined. It's better to use memory hotplug callback |
4401 | * function. |
4402 | */ |
4403 | if (!node_state(node, N_NORMAL_MEMORY)) |
4404 | tmp = -1; |
4405 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); |
4406 | if (!pn) |
4407 | return 1; |
4408 | |
4409 | mem->info.nodeinfo[node] = pn; |
4410 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
4411 | mz = &pn->zoneinfo[zone]; |
4412 | for_each_lru(l) |
4413 | INIT_LIST_HEAD(&mz->lists[l]); |
4414 | mz->usage_in_excess = 0; |
4415 | mz->on_tree = false; |
4416 | mz->mem = mem; |
4417 | } |
4418 | return 0; |
4419 | } |
4420 | |
4421 | static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
4422 | { |
4423 | kfree(mem->info.nodeinfo[node]); |
4424 | } |
4425 | |
4426 | static struct mem_cgroup *mem_cgroup_alloc(void) |
4427 | { |
4428 | struct mem_cgroup *mem; |
4429 | int size = sizeof(struct mem_cgroup); |
4430 | |
4431 | /* Can be very big if MAX_NUMNODES is very big */ |
4432 | if (size < PAGE_SIZE) |
4433 | mem = kzalloc(size, GFP_KERNEL); |
4434 | else |
4435 | mem = vzalloc(size); |
4436 | |
4437 | if (!mem) |
4438 | return NULL; |
4439 | |
4440 | mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu); |
4441 | if (!mem->stat) |
4442 | goto out_free; |
4443 | spin_lock_init(&mem->pcp_counter_lock); |
4444 | return mem; |
4445 | |
4446 | out_free: |
4447 | if (size < PAGE_SIZE) |
4448 | kfree(mem); |
4449 | else |
4450 | vfree(mem); |
4451 | return NULL; |
4452 | } |
4453 | |
4454 | /* |
4455 | * At destroying mem_cgroup, references from swap_cgroup can remain. |
4456 | * (scanning all at force_empty is too costly...) |
4457 | * |
4458 | * Instead of clearing all references at force_empty, we remember |
4459 | * the number of reference from swap_cgroup and free mem_cgroup when |
4460 | * it goes down to 0. |
4461 | * |
4462 | * Removal of cgroup itself succeeds regardless of refs from swap. |
4463 | */ |
4464 | |
4465 | static void __mem_cgroup_free(struct mem_cgroup *mem) |
4466 | { |
4467 | int node; |
4468 | |
4469 | mem_cgroup_remove_from_trees(mem); |
4470 | free_css_id(&mem_cgroup_subsys, &mem->css); |
4471 | |
4472 | for_each_node_state(node, N_POSSIBLE) |
4473 | free_mem_cgroup_per_zone_info(mem, node); |
4474 | |
4475 | free_percpu(mem->stat); |
4476 | if (sizeof(struct mem_cgroup) < PAGE_SIZE) |
4477 | kfree(mem); |
4478 | else |
4479 | vfree(mem); |
4480 | } |
4481 | |
4482 | static void mem_cgroup_get(struct mem_cgroup *mem) |
4483 | { |
4484 | atomic_inc(&mem->refcnt); |
4485 | } |
4486 | |
4487 | static void __mem_cgroup_put(struct mem_cgroup *mem, int count) |
4488 | { |
4489 | if (atomic_sub_and_test(count, &mem->refcnt)) { |
4490 | struct mem_cgroup *parent = parent_mem_cgroup(mem); |
4491 | __mem_cgroup_free(mem); |
4492 | if (parent) |
4493 | mem_cgroup_put(parent); |
4494 | } |
4495 | } |
4496 | |
4497 | static void mem_cgroup_put(struct mem_cgroup *mem) |
4498 | { |
4499 | __mem_cgroup_put(mem, 1); |
4500 | } |
4501 | |
4502 | /* |
4503 | * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. |
4504 | */ |
4505 | static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem) |
4506 | { |
4507 | if (!mem->res.parent) |
4508 | return NULL; |
4509 | return mem_cgroup_from_res_counter(mem->res.parent, res); |
4510 | } |
4511 | |
4512 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4513 | static void __init enable_swap_cgroup(void) |
4514 | { |
4515 | if (!mem_cgroup_disabled() && really_do_swap_account) |
4516 | do_swap_account = 1; |
4517 | } |
4518 | #else |
4519 | static void __init enable_swap_cgroup(void) |
4520 | { |
4521 | } |
4522 | #endif |
4523 | |
4524 | static int mem_cgroup_soft_limit_tree_init(void) |
4525 | { |
4526 | struct mem_cgroup_tree_per_node *rtpn; |
4527 | struct mem_cgroup_tree_per_zone *rtpz; |
4528 | int tmp, node, zone; |
4529 | |
4530 | for_each_node_state(node, N_POSSIBLE) { |
4531 | tmp = node; |
4532 | if (!node_state(node, N_NORMAL_MEMORY)) |
4533 | tmp = -1; |
4534 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, tmp); |
4535 | if (!rtpn) |
4536 | return 1; |
4537 | |
4538 | soft_limit_tree.rb_tree_per_node[node] = rtpn; |
4539 | |
4540 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
4541 | rtpz = &rtpn->rb_tree_per_zone[zone]; |
4542 | rtpz->rb_root = RB_ROOT; |
4543 | spin_lock_init(&rtpz->lock); |
4544 | } |
4545 | } |
4546 | return 0; |
4547 | } |
4548 | |
4549 | static struct cgroup_subsys_state * __ref |
4550 | mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) |
4551 | { |
4552 | struct mem_cgroup *mem, *parent; |
4553 | long error = -ENOMEM; |
4554 | int node; |
4555 | |
4556 | mem = mem_cgroup_alloc(); |
4557 | if (!mem) |
4558 | return ERR_PTR(error); |
4559 | |
4560 | for_each_node_state(node, N_POSSIBLE) |
4561 | if (alloc_mem_cgroup_per_zone_info(mem, node)) |
4562 | goto free_out; |
4563 | |
4564 | /* root ? */ |
4565 | if (cont->parent == NULL) { |
4566 | int cpu; |
4567 | enable_swap_cgroup(); |
4568 | parent = NULL; |
4569 | root_mem_cgroup = mem; |
4570 | if (mem_cgroup_soft_limit_tree_init()) |
4571 | goto free_out; |
4572 | for_each_possible_cpu(cpu) { |
4573 | struct memcg_stock_pcp *stock = |
4574 | &per_cpu(memcg_stock, cpu); |
4575 | INIT_WORK(&stock->work, drain_local_stock); |
4576 | } |
4577 | hotcpu_notifier(memcg_cpu_hotplug_callback, 0); |
4578 | } else { |
4579 | parent = mem_cgroup_from_cont(cont->parent); |
4580 | mem->use_hierarchy = parent->use_hierarchy; |
4581 | mem->oom_kill_disable = parent->oom_kill_disable; |
4582 | } |
4583 | |
4584 | if (parent && parent->use_hierarchy) { |
4585 | res_counter_init(&mem->res, &parent->res); |
4586 | res_counter_init(&mem->memsw, &parent->memsw); |
4587 | /* |
4588 | * We increment refcnt of the parent to ensure that we can |
4589 | * safely access it on res_counter_charge/uncharge. |
4590 | * This refcnt will be decremented when freeing this |
4591 | * mem_cgroup(see mem_cgroup_put). |
4592 | */ |
4593 | mem_cgroup_get(parent); |
4594 | } else { |
4595 | res_counter_init(&mem->res, NULL); |
4596 | res_counter_init(&mem->memsw, NULL); |
4597 | } |
4598 | mem->last_scanned_child = 0; |
4599 | INIT_LIST_HEAD(&mem->oom_notify); |
4600 | |
4601 | if (parent) |
4602 | mem->swappiness = get_swappiness(parent); |
4603 | atomic_set(&mem->refcnt, 1); |
4604 | mem->move_charge_at_immigrate = 0; |
4605 | mutex_init(&mem->thresholds_lock); |
4606 | return &mem->css; |
4607 | free_out: |
4608 | __mem_cgroup_free(mem); |
4609 | root_mem_cgroup = NULL; |
4610 | return ERR_PTR(error); |
4611 | } |
4612 | |
4613 | static int mem_cgroup_pre_destroy(struct cgroup_subsys *ss, |
4614 | struct cgroup *cont) |
4615 | { |
4616 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
4617 | |
4618 | return mem_cgroup_force_empty(mem, false); |
4619 | } |
4620 | |
4621 | static void mem_cgroup_destroy(struct cgroup_subsys *ss, |
4622 | struct cgroup *cont) |
4623 | { |
4624 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
4625 | |
4626 | mem_cgroup_put(mem); |
4627 | } |
4628 | |
4629 | static int mem_cgroup_populate(struct cgroup_subsys *ss, |
4630 | struct cgroup *cont) |
4631 | { |
4632 | int ret; |
4633 | |
4634 | ret = cgroup_add_files(cont, ss, mem_cgroup_files, |
4635 | ARRAY_SIZE(mem_cgroup_files)); |
4636 | |
4637 | if (!ret) |
4638 | ret = register_memsw_files(cont, ss); |
4639 | return ret; |
4640 | } |
4641 | |
4642 | #ifdef CONFIG_MMU |
4643 | /* Handlers for move charge at task migration. */ |
4644 | #define PRECHARGE_COUNT_AT_ONCE 256 |
4645 | static int mem_cgroup_do_precharge(unsigned long count) |
4646 | { |
4647 | int ret = 0; |
4648 | int batch_count = PRECHARGE_COUNT_AT_ONCE; |
4649 | struct mem_cgroup *mem = mc.to; |
4650 | |
4651 | if (mem_cgroup_is_root(mem)) { |
4652 | mc.precharge += count; |
4653 | /* we don't need css_get for root */ |
4654 | return ret; |
4655 | } |
4656 | /* try to charge at once */ |
4657 | if (count > 1) { |
4658 | struct res_counter *dummy; |
4659 | /* |
4660 | * "mem" cannot be under rmdir() because we've already checked |
4661 | * by cgroup_lock_live_cgroup() that it is not removed and we |
4662 | * are still under the same cgroup_mutex. So we can postpone |
4663 | * css_get(). |
4664 | */ |
4665 | if (res_counter_charge(&mem->res, PAGE_SIZE * count, &dummy)) |
4666 | goto one_by_one; |
4667 | if (do_swap_account && res_counter_charge(&mem->memsw, |
4668 | PAGE_SIZE * count, &dummy)) { |
4669 | res_counter_uncharge(&mem->res, PAGE_SIZE * count); |
4670 | goto one_by_one; |
4671 | } |
4672 | mc.precharge += count; |
4673 | return ret; |
4674 | } |
4675 | one_by_one: |
4676 | /* fall back to one by one charge */ |
4677 | while (count--) { |
4678 | if (signal_pending(current)) { |
4679 | ret = -EINTR; |
4680 | break; |
4681 | } |
4682 | if (!batch_count--) { |
4683 | batch_count = PRECHARGE_COUNT_AT_ONCE; |
4684 | cond_resched(); |
4685 | } |
4686 | ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, 1, &mem, false); |
4687 | if (ret || !mem) |
4688 | /* mem_cgroup_clear_mc() will do uncharge later */ |
4689 | return -ENOMEM; |
4690 | mc.precharge++; |
4691 | } |
4692 | return ret; |
4693 | } |
4694 | |
4695 | /** |
4696 | * is_target_pte_for_mc - check a pte whether it is valid for move charge |
4697 | * @vma: the vma the pte to be checked belongs |
4698 | * @addr: the address corresponding to the pte to be checked |
4699 | * @ptent: the pte to be checked |
4700 | * @target: the pointer the target page or swap ent will be stored(can be NULL) |
4701 | * |
4702 | * Returns |
4703 | * 0(MC_TARGET_NONE): if the pte is not a target for move charge. |
4704 | * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for |
4705 | * move charge. if @target is not NULL, the page is stored in target->page |
4706 | * with extra refcnt got(Callers should handle it). |
4707 | * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a |
4708 | * target for charge migration. if @target is not NULL, the entry is stored |
4709 | * in target->ent. |
4710 | * |
4711 | * Called with pte lock held. |
4712 | */ |
4713 | union mc_target { |
4714 | struct page *page; |
4715 | swp_entry_t ent; |
4716 | }; |
4717 | |
4718 | enum mc_target_type { |
4719 | MC_TARGET_NONE, /* not used */ |
4720 | MC_TARGET_PAGE, |
4721 | MC_TARGET_SWAP, |
4722 | }; |
4723 | |
4724 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
4725 | unsigned long addr, pte_t ptent) |
4726 | { |
4727 | struct page *page = vm_normal_page(vma, addr, ptent); |
4728 | |
4729 | if (!page || !page_mapped(page)) |
4730 | return NULL; |
4731 | if (PageAnon(page)) { |
4732 | /* we don't move shared anon */ |
4733 | if (!move_anon() || page_mapcount(page) > 2) |
4734 | return NULL; |
4735 | } else if (!move_file()) |
4736 | /* we ignore mapcount for file pages */ |
4737 | return NULL; |
4738 | if (!get_page_unless_zero(page)) |
4739 | return NULL; |
4740 | |
4741 | return page; |
4742 | } |
4743 | |
4744 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, |
4745 | unsigned long addr, pte_t ptent, swp_entry_t *entry) |
4746 | { |
4747 | int usage_count; |
4748 | struct page *page = NULL; |
4749 | swp_entry_t ent = pte_to_swp_entry(ptent); |
4750 | |
4751 | if (!move_anon() || non_swap_entry(ent)) |
4752 | return NULL; |
4753 | usage_count = mem_cgroup_count_swap_user(ent, &page); |
4754 | if (usage_count > 1) { /* we don't move shared anon */ |
4755 | if (page) |
4756 | put_page(page); |
4757 | return NULL; |
4758 | } |
4759 | if (do_swap_account) |
4760 | entry->val = ent.val; |
4761 | |
4762 | return page; |
4763 | } |
4764 | |
4765 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
4766 | unsigned long addr, pte_t ptent, swp_entry_t *entry) |
4767 | { |
4768 | struct page *page = NULL; |
4769 | struct inode *inode; |
4770 | struct address_space *mapping; |
4771 | pgoff_t pgoff; |
4772 | |
4773 | if (!vma->vm_file) /* anonymous vma */ |
4774 | return NULL; |
4775 | if (!move_file()) |
4776 | return NULL; |
4777 | |
4778 | inode = vma->vm_file->f_path.dentry->d_inode; |
4779 | mapping = vma->vm_file->f_mapping; |
4780 | if (pte_none(ptent)) |
4781 | pgoff = linear_page_index(vma, addr); |
4782 | else /* pte_file(ptent) is true */ |
4783 | pgoff = pte_to_pgoff(ptent); |
4784 | |
4785 | /* page is moved even if it's not RSS of this task(page-faulted). */ |
4786 | if (!mapping_cap_swap_backed(mapping)) { /* normal file */ |
4787 | page = find_get_page(mapping, pgoff); |
4788 | } else { /* shmem/tmpfs file. we should take account of swap too. */ |
4789 | swp_entry_t ent; |
4790 | mem_cgroup_get_shmem_target(inode, pgoff, &page, &ent); |
4791 | if (do_swap_account) |
4792 | entry->val = ent.val; |
4793 | } |
4794 | |
4795 | return page; |
4796 | } |
4797 | |
4798 | static int is_target_pte_for_mc(struct vm_area_struct *vma, |
4799 | unsigned long addr, pte_t ptent, union mc_target *target) |
4800 | { |
4801 | struct page *page = NULL; |
4802 | struct page_cgroup *pc; |
4803 | int ret = 0; |
4804 | swp_entry_t ent = { .val = 0 }; |
4805 | |
4806 | if (pte_present(ptent)) |
4807 | page = mc_handle_present_pte(vma, addr, ptent); |
4808 | else if (is_swap_pte(ptent)) |
4809 | page = mc_handle_swap_pte(vma, addr, ptent, &ent); |
4810 | else if (pte_none(ptent) || pte_file(ptent)) |
4811 | page = mc_handle_file_pte(vma, addr, ptent, &ent); |
4812 | |
4813 | if (!page && !ent.val) |
4814 | return 0; |
4815 | if (page) { |
4816 | pc = lookup_page_cgroup(page); |
4817 | /* |
4818 | * Do only loose check w/o page_cgroup lock. |
4819 | * mem_cgroup_move_account() checks the pc is valid or not under |
4820 | * the lock. |
4821 | */ |
4822 | if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { |
4823 | ret = MC_TARGET_PAGE; |
4824 | if (target) |
4825 | target->page = page; |
4826 | } |
4827 | if (!ret || !target) |
4828 | put_page(page); |
4829 | } |
4830 | /* There is a swap entry and a page doesn't exist or isn't charged */ |
4831 | if (ent.val && !ret && |
4832 | css_id(&mc.from->css) == lookup_swap_cgroup(ent)) { |
4833 | ret = MC_TARGET_SWAP; |
4834 | if (target) |
4835 | target->ent = ent; |
4836 | } |
4837 | return ret; |
4838 | } |
4839 | |
4840 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, |
4841 | unsigned long addr, unsigned long end, |
4842 | struct mm_walk *walk) |
4843 | { |
4844 | struct vm_area_struct *vma = walk->private; |
4845 | pte_t *pte; |
4846 | spinlock_t *ptl; |
4847 | |
4848 | split_huge_page_pmd(walk->mm, pmd); |
4849 | |
4850 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
4851 | for (; addr != end; pte++, addr += PAGE_SIZE) |
4852 | if (is_target_pte_for_mc(vma, addr, *pte, NULL)) |
4853 | mc.precharge++; /* increment precharge temporarily */ |
4854 | pte_unmap_unlock(pte - 1, ptl); |
4855 | cond_resched(); |
4856 | |
4857 | return 0; |
4858 | } |
4859 | |
4860 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
4861 | { |
4862 | unsigned long precharge; |
4863 | struct vm_area_struct *vma; |
4864 | |
4865 | down_read(&mm->mmap_sem); |
4866 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
4867 | struct mm_walk mem_cgroup_count_precharge_walk = { |
4868 | .pmd_entry = mem_cgroup_count_precharge_pte_range, |
4869 | .mm = mm, |
4870 | .private = vma, |
4871 | }; |
4872 | if (is_vm_hugetlb_page(vma)) |
4873 | continue; |
4874 | walk_page_range(vma->vm_start, vma->vm_end, |
4875 | &mem_cgroup_count_precharge_walk); |
4876 | } |
4877 | up_read(&mm->mmap_sem); |
4878 | |
4879 | precharge = mc.precharge; |
4880 | mc.precharge = 0; |
4881 | |
4882 | return precharge; |
4883 | } |
4884 | |
4885 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
4886 | { |
4887 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
4888 | |
4889 | VM_BUG_ON(mc.moving_task); |
4890 | mc.moving_task = current; |
4891 | return mem_cgroup_do_precharge(precharge); |
4892 | } |
4893 | |
4894 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
4895 | static void __mem_cgroup_clear_mc(void) |
4896 | { |
4897 | struct mem_cgroup *from = mc.from; |
4898 | struct mem_cgroup *to = mc.to; |
4899 | |
4900 | /* we must uncharge all the leftover precharges from mc.to */ |
4901 | if (mc.precharge) { |
4902 | __mem_cgroup_cancel_charge(mc.to, mc.precharge); |
4903 | mc.precharge = 0; |
4904 | } |
4905 | /* |
4906 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so |
4907 | * we must uncharge here. |
4908 | */ |
4909 | if (mc.moved_charge) { |
4910 | __mem_cgroup_cancel_charge(mc.from, mc.moved_charge); |
4911 | mc.moved_charge = 0; |
4912 | } |
4913 | /* we must fixup refcnts and charges */ |
4914 | if (mc.moved_swap) { |
4915 | /* uncharge swap account from the old cgroup */ |
4916 | if (!mem_cgroup_is_root(mc.from)) |
4917 | res_counter_uncharge(&mc.from->memsw, |
4918 | PAGE_SIZE * mc.moved_swap); |
4919 | __mem_cgroup_put(mc.from, mc.moved_swap); |
4920 | |
4921 | if (!mem_cgroup_is_root(mc.to)) { |
4922 | /* |
4923 | * we charged both to->res and to->memsw, so we should |
4924 | * uncharge to->res. |
4925 | */ |
4926 | res_counter_uncharge(&mc.to->res, |
4927 | PAGE_SIZE * mc.moved_swap); |
4928 | } |
4929 | /* we've already done mem_cgroup_get(mc.to) */ |
4930 | mc.moved_swap = 0; |
4931 | } |
4932 | memcg_oom_recover(from); |
4933 | memcg_oom_recover(to); |
4934 | wake_up_all(&mc.waitq); |
4935 | } |
4936 | |
4937 | static void mem_cgroup_clear_mc(void) |
4938 | { |
4939 | struct mem_cgroup *from = mc.from; |
4940 | |
4941 | /* |
4942 | * we must clear moving_task before waking up waiters at the end of |
4943 | * task migration. |
4944 | */ |
4945 | mc.moving_task = NULL; |
4946 | __mem_cgroup_clear_mc(); |
4947 | spin_lock(&mc.lock); |
4948 | mc.from = NULL; |
4949 | mc.to = NULL; |
4950 | spin_unlock(&mc.lock); |
4951 | mem_cgroup_end_move(from); |
4952 | } |
4953 | |
4954 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, |
4955 | struct cgroup *cgroup, |
4956 | struct task_struct *p, |
4957 | bool threadgroup) |
4958 | { |
4959 | int ret = 0; |
4960 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgroup); |
4961 | |
4962 | if (mem->move_charge_at_immigrate) { |
4963 | struct mm_struct *mm; |
4964 | struct mem_cgroup *from = mem_cgroup_from_task(p); |
4965 | |
4966 | VM_BUG_ON(from == mem); |
4967 | |
4968 | mm = get_task_mm(p); |
4969 | if (!mm) |
4970 | return 0; |
4971 | /* We move charges only when we move a owner of the mm */ |
4972 | if (mm->owner == p) { |
4973 | VM_BUG_ON(mc.from); |
4974 | VM_BUG_ON(mc.to); |
4975 | VM_BUG_ON(mc.precharge); |
4976 | VM_BUG_ON(mc.moved_charge); |
4977 | VM_BUG_ON(mc.moved_swap); |
4978 | mem_cgroup_start_move(from); |
4979 | spin_lock(&mc.lock); |
4980 | mc.from = from; |
4981 | mc.to = mem; |
4982 | spin_unlock(&mc.lock); |
4983 | /* We set mc.moving_task later */ |
4984 | |
4985 | ret = mem_cgroup_precharge_mc(mm); |
4986 | if (ret) |
4987 | mem_cgroup_clear_mc(); |
4988 | } |
4989 | mmput(mm); |
4990 | } |
4991 | return ret; |
4992 | } |
4993 | |
4994 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, |
4995 | struct cgroup *cgroup, |
4996 | struct task_struct *p, |
4997 | bool threadgroup) |
4998 | { |
4999 | mem_cgroup_clear_mc(); |
5000 | } |
5001 | |
5002 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
5003 | unsigned long addr, unsigned long end, |
5004 | struct mm_walk *walk) |
5005 | { |
5006 | int ret = 0; |
5007 | struct vm_area_struct *vma = walk->private; |
5008 | pte_t *pte; |
5009 | spinlock_t *ptl; |
5010 | |
5011 | split_huge_page_pmd(walk->mm, pmd); |
5012 | retry: |
5013 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
5014 | for (; addr != end; addr += PAGE_SIZE) { |
5015 | pte_t ptent = *(pte++); |
5016 | union mc_target target; |
5017 | int type; |
5018 | struct page *page; |
5019 | struct page_cgroup *pc; |
5020 | swp_entry_t ent; |
5021 | |
5022 | if (!mc.precharge) |
5023 | break; |
5024 | |
5025 | type = is_target_pte_for_mc(vma, addr, ptent, &target); |
5026 | switch (type) { |
5027 | case MC_TARGET_PAGE: |
5028 | page = target.page; |
5029 | if (isolate_lru_page(page)) |
5030 | goto put; |
5031 | pc = lookup_page_cgroup(page); |
5032 | if (!mem_cgroup_move_account(page, 1, pc, |
5033 | mc.from, mc.to, false)) { |
5034 | mc.precharge--; |
5035 | /* we uncharge from mc.from later. */ |
5036 | mc.moved_charge++; |
5037 | } |
5038 | putback_lru_page(page); |
5039 | put: /* is_target_pte_for_mc() gets the page */ |
5040 | put_page(page); |
5041 | break; |
5042 | case MC_TARGET_SWAP: |
5043 | ent = target.ent; |
5044 | if (!mem_cgroup_move_swap_account(ent, |
5045 | mc.from, mc.to, false)) { |
5046 | mc.precharge--; |
5047 | /* we fixup refcnts and charges later. */ |
5048 | mc.moved_swap++; |
5049 | } |
5050 | break; |
5051 | default: |
5052 | break; |
5053 | } |
5054 | } |
5055 | pte_unmap_unlock(pte - 1, ptl); |
5056 | cond_resched(); |
5057 | |
5058 | if (addr != end) { |
5059 | /* |
5060 | * We have consumed all precharges we got in can_attach(). |
5061 | * We try charge one by one, but don't do any additional |
5062 | * charges to mc.to if we have failed in charge once in attach() |
5063 | * phase. |
5064 | */ |
5065 | ret = mem_cgroup_do_precharge(1); |
5066 | if (!ret) |
5067 | goto retry; |
5068 | } |
5069 | |
5070 | return ret; |
5071 | } |
5072 | |
5073 | static void mem_cgroup_move_charge(struct mm_struct *mm) |
5074 | { |
5075 | struct vm_area_struct *vma; |
5076 | |
5077 | lru_add_drain_all(); |
5078 | retry: |
5079 | if (unlikely(!down_read_trylock(&mm->mmap_sem))) { |
5080 | /* |
5081 | * Someone who are holding the mmap_sem might be waiting in |
5082 | * waitq. So we cancel all extra charges, wake up all waiters, |
5083 | * and retry. Because we cancel precharges, we might not be able |
5084 | * to move enough charges, but moving charge is a best-effort |
5085 | * feature anyway, so it wouldn't be a big problem. |
5086 | */ |
5087 | __mem_cgroup_clear_mc(); |
5088 | cond_resched(); |
5089 | goto retry; |
5090 | } |
5091 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5092 | int ret; |
5093 | struct mm_walk mem_cgroup_move_charge_walk = { |
5094 | .pmd_entry = mem_cgroup_move_charge_pte_range, |
5095 | .mm = mm, |
5096 | .private = vma, |
5097 | }; |
5098 | if (is_vm_hugetlb_page(vma)) |
5099 | continue; |
5100 | ret = walk_page_range(vma->vm_start, vma->vm_end, |
5101 | &mem_cgroup_move_charge_walk); |
5102 | if (ret) |
5103 | /* |
5104 | * means we have consumed all precharges and failed in |
5105 | * doing additional charge. Just abandon here. |
5106 | */ |
5107 | break; |
5108 | } |
5109 | up_read(&mm->mmap_sem); |
5110 | } |
5111 | |
5112 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, |
5113 | struct cgroup *cont, |
5114 | struct cgroup *old_cont, |
5115 | struct task_struct *p, |
5116 | bool threadgroup) |
5117 | { |
5118 | struct mm_struct *mm; |
5119 | |
5120 | if (!mc.to) |
5121 | /* no need to move charge */ |
5122 | return; |
5123 | |
5124 | mm = get_task_mm(p); |
5125 | if (mm) { |
5126 | mem_cgroup_move_charge(mm); |
5127 | mmput(mm); |
5128 | } |
5129 | mem_cgroup_clear_mc(); |
5130 | } |
5131 | #else /* !CONFIG_MMU */ |
5132 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, |
5133 | struct cgroup *cgroup, |
5134 | struct task_struct *p, |
5135 | bool threadgroup) |
5136 | { |
5137 | return 0; |
5138 | } |
5139 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, |
5140 | struct cgroup *cgroup, |
5141 | struct task_struct *p, |
5142 | bool threadgroup) |
5143 | { |
5144 | } |
5145 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, |
5146 | struct cgroup *cont, |
5147 | struct cgroup *old_cont, |
5148 | struct task_struct *p, |
5149 | bool threadgroup) |
5150 | { |
5151 | } |
5152 | #endif |
5153 | |
5154 | struct cgroup_subsys mem_cgroup_subsys = { |
5155 | .name = "memory", |
5156 | .subsys_id = mem_cgroup_subsys_id, |
5157 | .create = mem_cgroup_create, |
5158 | .pre_destroy = mem_cgroup_pre_destroy, |
5159 | .destroy = mem_cgroup_destroy, |
5160 | .populate = mem_cgroup_populate, |
5161 | .can_attach = mem_cgroup_can_attach, |
5162 | .cancel_attach = mem_cgroup_cancel_attach, |
5163 | .attach = mem_cgroup_move_task, |
5164 | .early_init = 0, |
5165 | .use_id = 1, |
5166 | }; |
5167 | |
5168 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
5169 | static int __init enable_swap_account(char *s) |
5170 | { |
5171 | /* consider enabled if no parameter or 1 is given */ |
5172 | if (!(*s) || !strcmp(s, "=1")) |
5173 | really_do_swap_account = 1; |
5174 | else if (!strcmp(s, "=0")) |
5175 | really_do_swap_account = 0; |
5176 | return 1; |
5177 | } |
5178 | __setup("swapaccount", enable_swap_account); |
5179 | |
5180 | static int __init disable_swap_account(char *s) |
5181 | { |
5182 | printk_once("noswapaccount is deprecated and will be removed in 2.6.40. Use swapaccount=0 instead\n"); |
5183 | enable_swap_account("=0"); |
5184 | return 1; |
5185 | } |
5186 | __setup("noswapaccount", disable_swap_account); |
5187 | #endif |
5188 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9