]>
Commit | Line | Data |
---|---|---|
8cdea7c0 BS |
1 | /* memcontrol.c - Memory Controller |
2 | * | |
3 | * Copyright IBM Corporation, 2007 | |
4 | * Author Balbir Singh <balbir@linux.vnet.ibm.com> | |
5 | * | |
78fb7466 PE |
6 | * Copyright 2007 OpenVZ SWsoft Inc |
7 | * Author: Pavel Emelianov <xemul@openvz.org> | |
8 | * | |
8cdea7c0 BS |
9 | * This program is free software; you can redistribute it and/or modify |
10 | * it under the terms of the GNU General Public License as published by | |
11 | * the Free Software Foundation; either version 2 of the License, or | |
12 | * (at your option) any later version. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | * GNU General Public License for more details. | |
18 | */ | |
19 | ||
20 | #include <linux/res_counter.h> | |
21 | #include <linux/memcontrol.h> | |
22 | #include <linux/cgroup.h> | |
78fb7466 | 23 | #include <linux/mm.h> |
d13d1443 | 24 | #include <linux/pagemap.h> |
d52aa412 | 25 | #include <linux/smp.h> |
8a9f3ccd | 26 | #include <linux/page-flags.h> |
66e1707b | 27 | #include <linux/backing-dev.h> |
8a9f3ccd BS |
28 | #include <linux/bit_spinlock.h> |
29 | #include <linux/rcupdate.h> | |
8c7c6e34 | 30 | #include <linux/mutex.h> |
b6ac57d5 | 31 | #include <linux/slab.h> |
66e1707b BS |
32 | #include <linux/swap.h> |
33 | #include <linux/spinlock.h> | |
34 | #include <linux/fs.h> | |
d2ceb9b7 | 35 | #include <linux/seq_file.h> |
33327948 | 36 | #include <linux/vmalloc.h> |
b69408e8 | 37 | #include <linux/mm_inline.h> |
52d4b9ac | 38 | #include <linux/page_cgroup.h> |
08e552c6 | 39 | #include "internal.h" |
8cdea7c0 | 40 | |
8697d331 BS |
41 | #include <asm/uaccess.h> |
42 | ||
a181b0e8 | 43 | struct cgroup_subsys mem_cgroup_subsys __read_mostly; |
a181b0e8 | 44 | #define MEM_CGROUP_RECLAIM_RETRIES 5 |
8cdea7c0 | 45 | |
c077719b KH |
46 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
47 | /* Turned on only when memory cgroup is enabled && really_do_swap_account = 0 */ | |
48 | int do_swap_account __read_mostly; | |
49 | static int really_do_swap_account __initdata = 1; /* for remember boot option*/ | |
50 | #else | |
51 | #define do_swap_account (0) | |
52 | #endif | |
53 | ||
54 | ||
d52aa412 KH |
55 | /* |
56 | * Statistics for memory cgroup. | |
57 | */ | |
58 | enum mem_cgroup_stat_index { | |
59 | /* | |
60 | * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss. | |
61 | */ | |
62 | MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */ | |
63 | MEM_CGROUP_STAT_RSS, /* # of pages charged as rss */ | |
55e462b0 BR |
64 | MEM_CGROUP_STAT_PGPGIN_COUNT, /* # of pages paged in */ |
65 | MEM_CGROUP_STAT_PGPGOUT_COUNT, /* # of pages paged out */ | |
d52aa412 KH |
66 | |
67 | MEM_CGROUP_STAT_NSTATS, | |
68 | }; | |
69 | ||
70 | struct mem_cgroup_stat_cpu { | |
71 | s64 count[MEM_CGROUP_STAT_NSTATS]; | |
72 | } ____cacheline_aligned_in_smp; | |
73 | ||
74 | struct mem_cgroup_stat { | |
c8dad2bb | 75 | struct mem_cgroup_stat_cpu cpustat[0]; |
d52aa412 KH |
76 | }; |
77 | ||
78 | /* | |
79 | * For accounting under irq disable, no need for increment preempt count. | |
80 | */ | |
addb9efe | 81 | static inline void __mem_cgroup_stat_add_safe(struct mem_cgroup_stat_cpu *stat, |
d52aa412 KH |
82 | enum mem_cgroup_stat_index idx, int val) |
83 | { | |
addb9efe | 84 | stat->count[idx] += val; |
d52aa412 KH |
85 | } |
86 | ||
87 | static s64 mem_cgroup_read_stat(struct mem_cgroup_stat *stat, | |
88 | enum mem_cgroup_stat_index idx) | |
89 | { | |
90 | int cpu; | |
91 | s64 ret = 0; | |
92 | for_each_possible_cpu(cpu) | |
93 | ret += stat->cpustat[cpu].count[idx]; | |
94 | return ret; | |
95 | } | |
96 | ||
6d12e2d8 KH |
97 | /* |
98 | * per-zone information in memory controller. | |
99 | */ | |
6d12e2d8 | 100 | struct mem_cgroup_per_zone { |
072c56c1 KH |
101 | /* |
102 | * spin_lock to protect the per cgroup LRU | |
103 | */ | |
b69408e8 CL |
104 | struct list_head lists[NR_LRU_LISTS]; |
105 | unsigned long count[NR_LRU_LISTS]; | |
6d12e2d8 KH |
106 | }; |
107 | /* Macro for accessing counter */ | |
108 | #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)]) | |
109 | ||
110 | struct mem_cgroup_per_node { | |
111 | struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES]; | |
112 | }; | |
113 | ||
114 | struct mem_cgroup_lru_info { | |
115 | struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES]; | |
116 | }; | |
117 | ||
8cdea7c0 BS |
118 | /* |
119 | * The memory controller data structure. The memory controller controls both | |
120 | * page cache and RSS per cgroup. We would eventually like to provide | |
121 | * statistics based on the statistics developed by Rik Van Riel for clock-pro, | |
122 | * to help the administrator determine what knobs to tune. | |
123 | * | |
124 | * TODO: Add a water mark for the memory controller. Reclaim will begin when | |
8a9f3ccd BS |
125 | * we hit the water mark. May be even add a low water mark, such that |
126 | * no reclaim occurs from a cgroup at it's low water mark, this is | |
127 | * a feature that will be implemented much later in the future. | |
8cdea7c0 BS |
128 | */ |
129 | struct mem_cgroup { | |
130 | struct cgroup_subsys_state css; | |
131 | /* | |
132 | * the counter to account for memory usage | |
133 | */ | |
134 | struct res_counter res; | |
8c7c6e34 KH |
135 | /* |
136 | * the counter to account for mem+swap usage. | |
137 | */ | |
138 | struct res_counter memsw; | |
78fb7466 PE |
139 | /* |
140 | * Per cgroup active and inactive list, similar to the | |
141 | * per zone LRU lists. | |
78fb7466 | 142 | */ |
6d12e2d8 | 143 | struct mem_cgroup_lru_info info; |
072c56c1 | 144 | |
6c48a1d0 | 145 | int prev_priority; /* for recording reclaim priority */ |
6d61ef40 BS |
146 | |
147 | /* | |
148 | * While reclaiming in a hiearchy, we cache the last child we | |
149 | * reclaimed from. Protected by cgroup_lock() | |
150 | */ | |
151 | struct mem_cgroup *last_scanned_child; | |
152 | ||
8c7c6e34 KH |
153 | int obsolete; |
154 | atomic_t refcnt; | |
d52aa412 | 155 | /* |
c8dad2bb | 156 | * statistics. This must be placed at the end of memcg. |
d52aa412 KH |
157 | */ |
158 | struct mem_cgroup_stat stat; | |
8cdea7c0 BS |
159 | }; |
160 | ||
217bc319 KH |
161 | enum charge_type { |
162 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, | |
163 | MEM_CGROUP_CHARGE_TYPE_MAPPED, | |
4f98a2fe | 164 | MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ |
c05555b5 | 165 | MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ |
d13d1443 | 166 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
c05555b5 KH |
167 | NR_CHARGE_TYPE, |
168 | }; | |
169 | ||
52d4b9ac KH |
170 | /* only for here (for easy reading.) */ |
171 | #define PCGF_CACHE (1UL << PCG_CACHE) | |
172 | #define PCGF_USED (1UL << PCG_USED) | |
52d4b9ac | 173 | #define PCGF_LOCK (1UL << PCG_LOCK) |
c05555b5 KH |
174 | static const unsigned long |
175 | pcg_default_flags[NR_CHARGE_TYPE] = { | |
08e552c6 KH |
176 | PCGF_CACHE | PCGF_USED | PCGF_LOCK, /* File Cache */ |
177 | PCGF_USED | PCGF_LOCK, /* Anon */ | |
178 | PCGF_CACHE | PCGF_USED | PCGF_LOCK, /* Shmem */ | |
52d4b9ac | 179 | 0, /* FORCE */ |
217bc319 KH |
180 | }; |
181 | ||
8c7c6e34 KH |
182 | |
183 | /* for encoding cft->private value on file */ | |
184 | #define _MEM (0) | |
185 | #define _MEMSWAP (1) | |
186 | #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val)) | |
187 | #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff) | |
188 | #define MEMFILE_ATTR(val) ((val) & 0xffff) | |
189 | ||
190 | static void mem_cgroup_get(struct mem_cgroup *mem); | |
191 | static void mem_cgroup_put(struct mem_cgroup *mem); | |
192 | ||
c05555b5 KH |
193 | static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, |
194 | struct page_cgroup *pc, | |
195 | bool charge) | |
d52aa412 KH |
196 | { |
197 | int val = (charge)? 1 : -1; | |
198 | struct mem_cgroup_stat *stat = &mem->stat; | |
addb9efe | 199 | struct mem_cgroup_stat_cpu *cpustat; |
08e552c6 | 200 | int cpu = get_cpu(); |
d52aa412 | 201 | |
08e552c6 | 202 | cpustat = &stat->cpustat[cpu]; |
c05555b5 | 203 | if (PageCgroupCache(pc)) |
addb9efe | 204 | __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_CACHE, val); |
d52aa412 | 205 | else |
addb9efe | 206 | __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_RSS, val); |
55e462b0 BR |
207 | |
208 | if (charge) | |
addb9efe | 209 | __mem_cgroup_stat_add_safe(cpustat, |
55e462b0 BR |
210 | MEM_CGROUP_STAT_PGPGIN_COUNT, 1); |
211 | else | |
addb9efe | 212 | __mem_cgroup_stat_add_safe(cpustat, |
55e462b0 | 213 | MEM_CGROUP_STAT_PGPGOUT_COUNT, 1); |
08e552c6 | 214 | put_cpu(); |
6d12e2d8 KH |
215 | } |
216 | ||
d5b69e38 | 217 | static struct mem_cgroup_per_zone * |
6d12e2d8 KH |
218 | mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid) |
219 | { | |
6d12e2d8 KH |
220 | return &mem->info.nodeinfo[nid]->zoneinfo[zid]; |
221 | } | |
222 | ||
d5b69e38 | 223 | static struct mem_cgroup_per_zone * |
6d12e2d8 KH |
224 | page_cgroup_zoneinfo(struct page_cgroup *pc) |
225 | { | |
226 | struct mem_cgroup *mem = pc->mem_cgroup; | |
227 | int nid = page_cgroup_nid(pc); | |
228 | int zid = page_cgroup_zid(pc); | |
d52aa412 | 229 | |
6d12e2d8 KH |
230 | return mem_cgroup_zoneinfo(mem, nid, zid); |
231 | } | |
232 | ||
233 | static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup *mem, | |
b69408e8 | 234 | enum lru_list idx) |
6d12e2d8 KH |
235 | { |
236 | int nid, zid; | |
237 | struct mem_cgroup_per_zone *mz; | |
238 | u64 total = 0; | |
239 | ||
240 | for_each_online_node(nid) | |
241 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
242 | mz = mem_cgroup_zoneinfo(mem, nid, zid); | |
243 | total += MEM_CGROUP_ZSTAT(mz, idx); | |
244 | } | |
245 | return total; | |
d52aa412 KH |
246 | } |
247 | ||
d5b69e38 | 248 | static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) |
8cdea7c0 BS |
249 | { |
250 | return container_of(cgroup_subsys_state(cont, | |
251 | mem_cgroup_subsys_id), struct mem_cgroup, | |
252 | css); | |
253 | } | |
254 | ||
cf475ad2 | 255 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 256 | { |
31a78f23 BS |
257 | /* |
258 | * mm_update_next_owner() may clear mm->owner to NULL | |
259 | * if it races with swapoff, page migration, etc. | |
260 | * So this can be called with p == NULL. | |
261 | */ | |
262 | if (unlikely(!p)) | |
263 | return NULL; | |
264 | ||
78fb7466 PE |
265 | return container_of(task_subsys_state(p, mem_cgroup_subsys_id), |
266 | struct mem_cgroup, css); | |
267 | } | |
268 | ||
08e552c6 KH |
269 | /* |
270 | * Following LRU functions are allowed to be used without PCG_LOCK. | |
271 | * Operations are called by routine of global LRU independently from memcg. | |
272 | * What we have to take care of here is validness of pc->mem_cgroup. | |
273 | * | |
274 | * Changes to pc->mem_cgroup happens when | |
275 | * 1. charge | |
276 | * 2. moving account | |
277 | * In typical case, "charge" is done before add-to-lru. Exception is SwapCache. | |
278 | * It is added to LRU before charge. | |
279 | * If PCG_USED bit is not set, page_cgroup is not added to this private LRU. | |
280 | * When moving account, the page is not on LRU. It's isolated. | |
281 | */ | |
4f98a2fe | 282 | |
08e552c6 KH |
283 | void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru) |
284 | { | |
285 | struct page_cgroup *pc; | |
286 | struct mem_cgroup *mem; | |
287 | struct mem_cgroup_per_zone *mz; | |
6d12e2d8 | 288 | |
f8d66542 | 289 | if (mem_cgroup_disabled()) |
08e552c6 KH |
290 | return; |
291 | pc = lookup_page_cgroup(page); | |
292 | /* can happen while we handle swapcache. */ | |
293 | if (list_empty(&pc->lru)) | |
294 | return; | |
295 | mz = page_cgroup_zoneinfo(pc); | |
296 | mem = pc->mem_cgroup; | |
b69408e8 | 297 | MEM_CGROUP_ZSTAT(mz, lru) -= 1; |
08e552c6 KH |
298 | list_del_init(&pc->lru); |
299 | return; | |
6d12e2d8 KH |
300 | } |
301 | ||
08e552c6 | 302 | void mem_cgroup_del_lru(struct page *page) |
6d12e2d8 | 303 | { |
08e552c6 KH |
304 | mem_cgroup_del_lru_list(page, page_lru(page)); |
305 | } | |
b69408e8 | 306 | |
08e552c6 KH |
307 | void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru) |
308 | { | |
309 | struct mem_cgroup_per_zone *mz; | |
310 | struct page_cgroup *pc; | |
b69408e8 | 311 | |
f8d66542 | 312 | if (mem_cgroup_disabled()) |
08e552c6 | 313 | return; |
6d12e2d8 | 314 | |
08e552c6 KH |
315 | pc = lookup_page_cgroup(page); |
316 | smp_rmb(); | |
317 | /* unused page is not rotated. */ | |
318 | if (!PageCgroupUsed(pc)) | |
319 | return; | |
320 | mz = page_cgroup_zoneinfo(pc); | |
321 | list_move(&pc->lru, &mz->lists[lru]); | |
6d12e2d8 KH |
322 | } |
323 | ||
08e552c6 | 324 | void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru) |
66e1707b | 325 | { |
08e552c6 KH |
326 | struct page_cgroup *pc; |
327 | struct mem_cgroup_per_zone *mz; | |
6d12e2d8 | 328 | |
f8d66542 | 329 | if (mem_cgroup_disabled()) |
08e552c6 KH |
330 | return; |
331 | pc = lookup_page_cgroup(page); | |
332 | /* barrier to sync with "charge" */ | |
333 | smp_rmb(); | |
334 | if (!PageCgroupUsed(pc)) | |
894bc310 | 335 | return; |
b69408e8 | 336 | |
08e552c6 | 337 | mz = page_cgroup_zoneinfo(pc); |
b69408e8 | 338 | MEM_CGROUP_ZSTAT(mz, lru) += 1; |
08e552c6 KH |
339 | list_add(&pc->lru, &mz->lists[lru]); |
340 | } | |
341 | /* | |
342 | * To add swapcache into LRU. Be careful to all this function. | |
343 | * zone->lru_lock shouldn't be held and irq must not be disabled. | |
344 | */ | |
345 | static void mem_cgroup_lru_fixup(struct page *page) | |
346 | { | |
347 | if (!isolate_lru_page(page)) | |
348 | putback_lru_page(page); | |
349 | } | |
350 | ||
351 | void mem_cgroup_move_lists(struct page *page, | |
352 | enum lru_list from, enum lru_list to) | |
353 | { | |
f8d66542 | 354 | if (mem_cgroup_disabled()) |
08e552c6 KH |
355 | return; |
356 | mem_cgroup_del_lru_list(page, from); | |
357 | mem_cgroup_add_lru_list(page, to); | |
66e1707b BS |
358 | } |
359 | ||
4c4a2214 DR |
360 | int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem) |
361 | { | |
362 | int ret; | |
363 | ||
364 | task_lock(task); | |
bd845e38 | 365 | ret = task->mm && mm_match_cgroup(task->mm, mem); |
4c4a2214 DR |
366 | task_unlock(task); |
367 | return ret; | |
368 | } | |
369 | ||
58ae83db KH |
370 | /* |
371 | * Calculate mapped_ratio under memory controller. This will be used in | |
372 | * vmscan.c for deteremining we have to reclaim mapped pages. | |
373 | */ | |
374 | int mem_cgroup_calc_mapped_ratio(struct mem_cgroup *mem) | |
375 | { | |
376 | long total, rss; | |
377 | ||
378 | /* | |
379 | * usage is recorded in bytes. But, here, we assume the number of | |
380 | * physical pages can be represented by "long" on any arch. | |
381 | */ | |
382 | total = (long) (mem->res.usage >> PAGE_SHIFT) + 1L; | |
383 | rss = (long)mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_RSS); | |
384 | return (int)((rss * 100L) / total); | |
385 | } | |
8869b8f6 | 386 | |
6c48a1d0 KH |
387 | /* |
388 | * prev_priority control...this will be used in memory reclaim path. | |
389 | */ | |
390 | int mem_cgroup_get_reclaim_priority(struct mem_cgroup *mem) | |
391 | { | |
392 | return mem->prev_priority; | |
393 | } | |
394 | ||
395 | void mem_cgroup_note_reclaim_priority(struct mem_cgroup *mem, int priority) | |
396 | { | |
397 | if (priority < mem->prev_priority) | |
398 | mem->prev_priority = priority; | |
399 | } | |
400 | ||
401 | void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, int priority) | |
402 | { | |
403 | mem->prev_priority = priority; | |
404 | } | |
405 | ||
cc38108e KH |
406 | /* |
407 | * Calculate # of pages to be scanned in this priority/zone. | |
408 | * See also vmscan.c | |
409 | * | |
410 | * priority starts from "DEF_PRIORITY" and decremented in each loop. | |
411 | * (see include/linux/mmzone.h) | |
412 | */ | |
413 | ||
b69408e8 CL |
414 | long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, struct zone *zone, |
415 | int priority, enum lru_list lru) | |
cc38108e | 416 | { |
b69408e8 | 417 | long nr_pages; |
cc38108e KH |
418 | int nid = zone->zone_pgdat->node_id; |
419 | int zid = zone_idx(zone); | |
420 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(mem, nid, zid); | |
421 | ||
b69408e8 | 422 | nr_pages = MEM_CGROUP_ZSTAT(mz, lru); |
cc38108e | 423 | |
b69408e8 | 424 | return (nr_pages >> priority); |
cc38108e KH |
425 | } |
426 | ||
66e1707b BS |
427 | unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, |
428 | struct list_head *dst, | |
429 | unsigned long *scanned, int order, | |
430 | int mode, struct zone *z, | |
431 | struct mem_cgroup *mem_cont, | |
4f98a2fe | 432 | int active, int file) |
66e1707b BS |
433 | { |
434 | unsigned long nr_taken = 0; | |
435 | struct page *page; | |
436 | unsigned long scan; | |
437 | LIST_HEAD(pc_list); | |
438 | struct list_head *src; | |
ff7283fa | 439 | struct page_cgroup *pc, *tmp; |
1ecaab2b KH |
440 | int nid = z->zone_pgdat->node_id; |
441 | int zid = zone_idx(z); | |
442 | struct mem_cgroup_per_zone *mz; | |
4f98a2fe | 443 | int lru = LRU_FILE * !!file + !!active; |
66e1707b | 444 | |
cf475ad2 | 445 | BUG_ON(!mem_cont); |
1ecaab2b | 446 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); |
b69408e8 | 447 | src = &mz->lists[lru]; |
66e1707b | 448 | |
ff7283fa KH |
449 | scan = 0; |
450 | list_for_each_entry_safe_reverse(pc, tmp, src, lru) { | |
436c6541 | 451 | if (scan >= nr_to_scan) |
ff7283fa | 452 | break; |
08e552c6 KH |
453 | |
454 | page = pc->page; | |
52d4b9ac KH |
455 | if (unlikely(!PageCgroupUsed(pc))) |
456 | continue; | |
436c6541 | 457 | if (unlikely(!PageLRU(page))) |
ff7283fa | 458 | continue; |
ff7283fa | 459 | |
436c6541 | 460 | scan++; |
4f98a2fe | 461 | if (__isolate_lru_page(page, mode, file) == 0) { |
66e1707b BS |
462 | list_move(&page->lru, dst); |
463 | nr_taken++; | |
464 | } | |
465 | } | |
466 | ||
66e1707b BS |
467 | *scanned = scan; |
468 | return nr_taken; | |
469 | } | |
470 | ||
6d61ef40 BS |
471 | #define mem_cgroup_from_res_counter(counter, member) \ |
472 | container_of(counter, struct mem_cgroup, member) | |
473 | ||
474 | /* | |
475 | * This routine finds the DFS walk successor. This routine should be | |
476 | * called with cgroup_mutex held | |
477 | */ | |
478 | static struct mem_cgroup * | |
479 | mem_cgroup_get_next_node(struct mem_cgroup *curr, struct mem_cgroup *root_mem) | |
480 | { | |
481 | struct cgroup *cgroup, *curr_cgroup, *root_cgroup; | |
482 | ||
483 | curr_cgroup = curr->css.cgroup; | |
484 | root_cgroup = root_mem->css.cgroup; | |
485 | ||
486 | if (!list_empty(&curr_cgroup->children)) { | |
487 | /* | |
488 | * Walk down to children | |
489 | */ | |
490 | mem_cgroup_put(curr); | |
491 | cgroup = list_entry(curr_cgroup->children.next, | |
492 | struct cgroup, sibling); | |
493 | curr = mem_cgroup_from_cont(cgroup); | |
494 | mem_cgroup_get(curr); | |
495 | goto done; | |
496 | } | |
497 | ||
498 | visit_parent: | |
499 | if (curr_cgroup == root_cgroup) { | |
500 | mem_cgroup_put(curr); | |
501 | curr = root_mem; | |
502 | mem_cgroup_get(curr); | |
503 | goto done; | |
504 | } | |
505 | ||
506 | /* | |
507 | * Goto next sibling | |
508 | */ | |
509 | if (curr_cgroup->sibling.next != &curr_cgroup->parent->children) { | |
510 | mem_cgroup_put(curr); | |
511 | cgroup = list_entry(curr_cgroup->sibling.next, struct cgroup, | |
512 | sibling); | |
513 | curr = mem_cgroup_from_cont(cgroup); | |
514 | mem_cgroup_get(curr); | |
515 | goto done; | |
516 | } | |
517 | ||
518 | /* | |
519 | * Go up to next parent and next parent's sibling if need be | |
520 | */ | |
521 | curr_cgroup = curr_cgroup->parent; | |
522 | goto visit_parent; | |
523 | ||
524 | done: | |
525 | root_mem->last_scanned_child = curr; | |
526 | return curr; | |
527 | } | |
528 | ||
529 | /* | |
530 | * Visit the first child (need not be the first child as per the ordering | |
531 | * of the cgroup list, since we track last_scanned_child) of @mem and use | |
532 | * that to reclaim free pages from. | |
533 | */ | |
534 | static struct mem_cgroup * | |
535 | mem_cgroup_get_first_node(struct mem_cgroup *root_mem) | |
536 | { | |
537 | struct cgroup *cgroup; | |
538 | struct mem_cgroup *ret; | |
539 | bool obsolete = (root_mem->last_scanned_child && | |
540 | root_mem->last_scanned_child->obsolete); | |
541 | ||
542 | /* | |
543 | * Scan all children under the mem_cgroup mem | |
544 | */ | |
545 | cgroup_lock(); | |
546 | if (list_empty(&root_mem->css.cgroup->children)) { | |
547 | ret = root_mem; | |
548 | goto done; | |
549 | } | |
550 | ||
551 | if (!root_mem->last_scanned_child || obsolete) { | |
552 | ||
553 | if (obsolete) | |
554 | mem_cgroup_put(root_mem->last_scanned_child); | |
555 | ||
556 | cgroup = list_first_entry(&root_mem->css.cgroup->children, | |
557 | struct cgroup, sibling); | |
558 | ret = mem_cgroup_from_cont(cgroup); | |
559 | mem_cgroup_get(ret); | |
560 | } else | |
561 | ret = mem_cgroup_get_next_node(root_mem->last_scanned_child, | |
562 | root_mem); | |
563 | ||
564 | done: | |
565 | root_mem->last_scanned_child = ret; | |
566 | cgroup_unlock(); | |
567 | return ret; | |
568 | } | |
569 | ||
570 | /* | |
571 | * Dance down the hierarchy if needed to reclaim memory. We remember the | |
572 | * last child we reclaimed from, so that we don't end up penalizing | |
573 | * one child extensively based on its position in the children list. | |
574 | * | |
575 | * root_mem is the original ancestor that we've been reclaim from. | |
576 | */ | |
577 | static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, | |
578 | gfp_t gfp_mask, bool noswap) | |
579 | { | |
580 | struct mem_cgroup *next_mem; | |
581 | int ret = 0; | |
582 | ||
583 | /* | |
584 | * Reclaim unconditionally and don't check for return value. | |
585 | * We need to reclaim in the current group and down the tree. | |
586 | * One might think about checking for children before reclaiming, | |
587 | * but there might be left over accounting, even after children | |
588 | * have left. | |
589 | */ | |
590 | ret = try_to_free_mem_cgroup_pages(root_mem, gfp_mask, noswap); | |
591 | if (res_counter_check_under_limit(&root_mem->res)) | |
592 | return 0; | |
593 | ||
594 | next_mem = mem_cgroup_get_first_node(root_mem); | |
595 | ||
596 | while (next_mem != root_mem) { | |
597 | if (next_mem->obsolete) { | |
598 | mem_cgroup_put(next_mem); | |
599 | cgroup_lock(); | |
600 | next_mem = mem_cgroup_get_first_node(root_mem); | |
601 | cgroup_unlock(); | |
602 | continue; | |
603 | } | |
604 | ret = try_to_free_mem_cgroup_pages(next_mem, gfp_mask, noswap); | |
605 | if (res_counter_check_under_limit(&root_mem->res)) | |
606 | return 0; | |
607 | cgroup_lock(); | |
608 | next_mem = mem_cgroup_get_next_node(next_mem, root_mem); | |
609 | cgroup_unlock(); | |
610 | } | |
611 | return ret; | |
612 | } | |
613 | ||
f817ed48 KH |
614 | /* |
615 | * Unlike exported interface, "oom" parameter is added. if oom==true, | |
616 | * oom-killer can be invoked. | |
8a9f3ccd | 617 | */ |
f817ed48 | 618 | static int __mem_cgroup_try_charge(struct mm_struct *mm, |
8c7c6e34 KH |
619 | gfp_t gfp_mask, struct mem_cgroup **memcg, |
620 | bool oom) | |
8a9f3ccd | 621 | { |
6d61ef40 | 622 | struct mem_cgroup *mem, *mem_over_limit; |
7a81b88c | 623 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; |
28dbc4b6 | 624 | struct res_counter *fail_res; |
8a9f3ccd | 625 | /* |
3be91277 HD |
626 | * We always charge the cgroup the mm_struct belongs to. |
627 | * The mm_struct's mem_cgroup changes on task migration if the | |
8a9f3ccd BS |
628 | * thread group leader migrates. It's possible that mm is not |
629 | * set, if so charge the init_mm (happens for pagecache usage). | |
630 | */ | |
7a81b88c | 631 | if (likely(!*memcg)) { |
e8589cc1 KH |
632 | rcu_read_lock(); |
633 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
31a78f23 BS |
634 | if (unlikely(!mem)) { |
635 | rcu_read_unlock(); | |
31a78f23 BS |
636 | return 0; |
637 | } | |
e8589cc1 KH |
638 | /* |
639 | * For every charge from the cgroup, increment reference count | |
640 | */ | |
641 | css_get(&mem->css); | |
7a81b88c | 642 | *memcg = mem; |
e8589cc1 KH |
643 | rcu_read_unlock(); |
644 | } else { | |
7a81b88c KH |
645 | mem = *memcg; |
646 | css_get(&mem->css); | |
e8589cc1 | 647 | } |
8a9f3ccd | 648 | |
8c7c6e34 KH |
649 | while (1) { |
650 | int ret; | |
651 | bool noswap = false; | |
7a81b88c | 652 | |
28dbc4b6 | 653 | ret = res_counter_charge(&mem->res, PAGE_SIZE, &fail_res); |
8c7c6e34 KH |
654 | if (likely(!ret)) { |
655 | if (!do_swap_account) | |
656 | break; | |
28dbc4b6 BS |
657 | ret = res_counter_charge(&mem->memsw, PAGE_SIZE, |
658 | &fail_res); | |
8c7c6e34 KH |
659 | if (likely(!ret)) |
660 | break; | |
661 | /* mem+swap counter fails */ | |
662 | res_counter_uncharge(&mem->res, PAGE_SIZE); | |
663 | noswap = true; | |
6d61ef40 BS |
664 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, |
665 | memsw); | |
666 | } else | |
667 | /* mem counter fails */ | |
668 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, | |
669 | res); | |
670 | ||
3be91277 | 671 | if (!(gfp_mask & __GFP_WAIT)) |
7a81b88c | 672 | goto nomem; |
e1a1cd59 | 673 | |
6d61ef40 BS |
674 | ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, gfp_mask, |
675 | noswap); | |
66e1707b BS |
676 | |
677 | /* | |
8869b8f6 HD |
678 | * try_to_free_mem_cgroup_pages() might not give us a full |
679 | * picture of reclaim. Some pages are reclaimed and might be | |
680 | * moved to swap cache or just unmapped from the cgroup. | |
681 | * Check the limit again to see if the reclaim reduced the | |
682 | * current usage of the cgroup before giving up | |
8c7c6e34 | 683 | * |
8869b8f6 | 684 | */ |
8c7c6e34 KH |
685 | if (!do_swap_account && |
686 | res_counter_check_under_limit(&mem->res)) | |
687 | continue; | |
688 | if (do_swap_account && | |
689 | res_counter_check_under_limit(&mem->memsw)) | |
66e1707b | 690 | continue; |
3be91277 HD |
691 | |
692 | if (!nr_retries--) { | |
f817ed48 KH |
693 | if (oom) |
694 | mem_cgroup_out_of_memory(mem, gfp_mask); | |
7a81b88c | 695 | goto nomem; |
66e1707b | 696 | } |
8a9f3ccd | 697 | } |
7a81b88c KH |
698 | return 0; |
699 | nomem: | |
700 | css_put(&mem->css); | |
701 | return -ENOMEM; | |
702 | } | |
8a9f3ccd | 703 | |
f817ed48 KH |
704 | /** |
705 | * mem_cgroup_try_charge - get charge of PAGE_SIZE. | |
706 | * @mm: an mm_struct which is charged against. (when *memcg is NULL) | |
707 | * @gfp_mask: gfp_mask for reclaim. | |
708 | * @memcg: a pointer to memory cgroup which is charged against. | |
709 | * | |
710 | * charge against memory cgroup pointed by *memcg. if *memcg == NULL, estimated | |
711 | * memory cgroup from @mm is got and stored in *memcg. | |
712 | * | |
713 | * Returns 0 if success. -ENOMEM at failure. | |
714 | * This call can invoke OOM-Killer. | |
715 | */ | |
716 | ||
717 | int mem_cgroup_try_charge(struct mm_struct *mm, | |
718 | gfp_t mask, struct mem_cgroup **memcg) | |
719 | { | |
720 | return __mem_cgroup_try_charge(mm, mask, memcg, true); | |
721 | } | |
722 | ||
7a81b88c KH |
723 | /* |
724 | * commit a charge got by mem_cgroup_try_charge() and makes page_cgroup to be | |
725 | * USED state. If already USED, uncharge and return. | |
726 | */ | |
727 | ||
728 | static void __mem_cgroup_commit_charge(struct mem_cgroup *mem, | |
729 | struct page_cgroup *pc, | |
730 | enum charge_type ctype) | |
731 | { | |
7a81b88c KH |
732 | /* try_charge() can return NULL to *memcg, taking care of it. */ |
733 | if (!mem) | |
734 | return; | |
52d4b9ac KH |
735 | |
736 | lock_page_cgroup(pc); | |
737 | if (unlikely(PageCgroupUsed(pc))) { | |
738 | unlock_page_cgroup(pc); | |
739 | res_counter_uncharge(&mem->res, PAGE_SIZE); | |
8c7c6e34 KH |
740 | if (do_swap_account) |
741 | res_counter_uncharge(&mem->memsw, PAGE_SIZE); | |
52d4b9ac | 742 | css_put(&mem->css); |
7a81b88c | 743 | return; |
52d4b9ac | 744 | } |
8a9f3ccd | 745 | pc->mem_cgroup = mem; |
08e552c6 | 746 | smp_wmb(); |
c05555b5 | 747 | pc->flags = pcg_default_flags[ctype]; |
3be91277 | 748 | |
08e552c6 | 749 | mem_cgroup_charge_statistics(mem, pc, true); |
52d4b9ac | 750 | |
52d4b9ac | 751 | unlock_page_cgroup(pc); |
7a81b88c | 752 | } |
66e1707b | 753 | |
f817ed48 KH |
754 | /** |
755 | * mem_cgroup_move_account - move account of the page | |
756 | * @pc: page_cgroup of the page. | |
757 | * @from: mem_cgroup which the page is moved from. | |
758 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
759 | * | |
760 | * The caller must confirm following. | |
08e552c6 | 761 | * - page is not on LRU (isolate_page() is useful.) |
f817ed48 KH |
762 | * |
763 | * returns 0 at success, | |
764 | * returns -EBUSY when lock is busy or "pc" is unstable. | |
765 | * | |
766 | * This function does "uncharge" from old cgroup but doesn't do "charge" to | |
767 | * new cgroup. It should be done by a caller. | |
768 | */ | |
769 | ||
770 | static int mem_cgroup_move_account(struct page_cgroup *pc, | |
771 | struct mem_cgroup *from, struct mem_cgroup *to) | |
772 | { | |
773 | struct mem_cgroup_per_zone *from_mz, *to_mz; | |
774 | int nid, zid; | |
775 | int ret = -EBUSY; | |
776 | ||
f817ed48 | 777 | VM_BUG_ON(from == to); |
08e552c6 | 778 | VM_BUG_ON(PageLRU(pc->page)); |
f817ed48 KH |
779 | |
780 | nid = page_cgroup_nid(pc); | |
781 | zid = page_cgroup_zid(pc); | |
782 | from_mz = mem_cgroup_zoneinfo(from, nid, zid); | |
783 | to_mz = mem_cgroup_zoneinfo(to, nid, zid); | |
784 | ||
f817ed48 KH |
785 | if (!trylock_page_cgroup(pc)) |
786 | return ret; | |
787 | ||
788 | if (!PageCgroupUsed(pc)) | |
789 | goto out; | |
790 | ||
791 | if (pc->mem_cgroup != from) | |
792 | goto out; | |
793 | ||
08e552c6 KH |
794 | css_put(&from->css); |
795 | res_counter_uncharge(&from->res, PAGE_SIZE); | |
796 | mem_cgroup_charge_statistics(from, pc, false); | |
797 | if (do_swap_account) | |
798 | res_counter_uncharge(&from->memsw, PAGE_SIZE); | |
799 | pc->mem_cgroup = to; | |
800 | mem_cgroup_charge_statistics(to, pc, true); | |
801 | css_get(&to->css); | |
802 | ret = 0; | |
f817ed48 KH |
803 | out: |
804 | unlock_page_cgroup(pc); | |
805 | return ret; | |
806 | } | |
807 | ||
808 | /* | |
809 | * move charges to its parent. | |
810 | */ | |
811 | ||
812 | static int mem_cgroup_move_parent(struct page_cgroup *pc, | |
813 | struct mem_cgroup *child, | |
814 | gfp_t gfp_mask) | |
815 | { | |
08e552c6 | 816 | struct page *page = pc->page; |
f817ed48 KH |
817 | struct cgroup *cg = child->css.cgroup; |
818 | struct cgroup *pcg = cg->parent; | |
819 | struct mem_cgroup *parent; | |
f817ed48 KH |
820 | int ret; |
821 | ||
822 | /* Is ROOT ? */ | |
823 | if (!pcg) | |
824 | return -EINVAL; | |
825 | ||
08e552c6 | 826 | |
f817ed48 KH |
827 | parent = mem_cgroup_from_cont(pcg); |
828 | ||
08e552c6 | 829 | |
f817ed48 KH |
830 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false); |
831 | if (ret) | |
832 | return ret; | |
833 | ||
08e552c6 KH |
834 | if (!get_page_unless_zero(page)) |
835 | return -EBUSY; | |
836 | ||
837 | ret = isolate_lru_page(page); | |
838 | ||
839 | if (ret) | |
840 | goto cancel; | |
f817ed48 | 841 | |
f817ed48 | 842 | ret = mem_cgroup_move_account(pc, child, parent); |
f817ed48 | 843 | |
08e552c6 | 844 | /* drop extra refcnt by try_charge() (move_account increment one) */ |
f817ed48 | 845 | css_put(&parent->css); |
08e552c6 KH |
846 | putback_lru_page(page); |
847 | if (!ret) { | |
848 | put_page(page); | |
849 | return 0; | |
8c7c6e34 | 850 | } |
08e552c6 KH |
851 | /* uncharge if move fails */ |
852 | cancel: | |
853 | res_counter_uncharge(&parent->res, PAGE_SIZE); | |
854 | if (do_swap_account) | |
855 | res_counter_uncharge(&parent->memsw, PAGE_SIZE); | |
856 | put_page(page); | |
f817ed48 KH |
857 | return ret; |
858 | } | |
859 | ||
7a81b88c KH |
860 | /* |
861 | * Charge the memory controller for page usage. | |
862 | * Return | |
863 | * 0 if the charge was successful | |
864 | * < 0 if the cgroup is over its limit | |
865 | */ | |
866 | static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, | |
867 | gfp_t gfp_mask, enum charge_type ctype, | |
868 | struct mem_cgroup *memcg) | |
869 | { | |
870 | struct mem_cgroup *mem; | |
871 | struct page_cgroup *pc; | |
872 | int ret; | |
873 | ||
874 | pc = lookup_page_cgroup(page); | |
875 | /* can happen at boot */ | |
876 | if (unlikely(!pc)) | |
877 | return 0; | |
878 | prefetchw(pc); | |
879 | ||
880 | mem = memcg; | |
f817ed48 | 881 | ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, true); |
7a81b88c KH |
882 | if (ret) |
883 | return ret; | |
884 | ||
885 | __mem_cgroup_commit_charge(mem, pc, ctype); | |
8a9f3ccd | 886 | return 0; |
8a9f3ccd BS |
887 | } |
888 | ||
7a81b88c KH |
889 | int mem_cgroup_newpage_charge(struct page *page, |
890 | struct mm_struct *mm, gfp_t gfp_mask) | |
217bc319 | 891 | { |
f8d66542 | 892 | if (mem_cgroup_disabled()) |
cede86ac | 893 | return 0; |
52d4b9ac KH |
894 | if (PageCompound(page)) |
895 | return 0; | |
69029cd5 KH |
896 | /* |
897 | * If already mapped, we don't have to account. | |
898 | * If page cache, page->mapping has address_space. | |
899 | * But page->mapping may have out-of-use anon_vma pointer, | |
900 | * detecit it by PageAnon() check. newly-mapped-anon's page->mapping | |
901 | * is NULL. | |
902 | */ | |
903 | if (page_mapped(page) || (page->mapping && !PageAnon(page))) | |
904 | return 0; | |
905 | if (unlikely(!mm)) | |
906 | mm = &init_mm; | |
217bc319 | 907 | return mem_cgroup_charge_common(page, mm, gfp_mask, |
e8589cc1 | 908 | MEM_CGROUP_CHARGE_TYPE_MAPPED, NULL); |
217bc319 KH |
909 | } |
910 | ||
e1a1cd59 BS |
911 | int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, |
912 | gfp_t gfp_mask) | |
8697d331 | 913 | { |
f8d66542 | 914 | if (mem_cgroup_disabled()) |
cede86ac | 915 | return 0; |
52d4b9ac KH |
916 | if (PageCompound(page)) |
917 | return 0; | |
accf163e KH |
918 | /* |
919 | * Corner case handling. This is called from add_to_page_cache() | |
920 | * in usual. But some FS (shmem) precharges this page before calling it | |
921 | * and call add_to_page_cache() with GFP_NOWAIT. | |
922 | * | |
923 | * For GFP_NOWAIT case, the page may be pre-charged before calling | |
924 | * add_to_page_cache(). (See shmem.c) check it here and avoid to call | |
925 | * charge twice. (It works but has to pay a bit larger cost.) | |
926 | */ | |
927 | if (!(gfp_mask & __GFP_WAIT)) { | |
928 | struct page_cgroup *pc; | |
929 | ||
52d4b9ac KH |
930 | |
931 | pc = lookup_page_cgroup(page); | |
932 | if (!pc) | |
933 | return 0; | |
934 | lock_page_cgroup(pc); | |
935 | if (PageCgroupUsed(pc)) { | |
936 | unlock_page_cgroup(pc); | |
accf163e KH |
937 | return 0; |
938 | } | |
52d4b9ac | 939 | unlock_page_cgroup(pc); |
accf163e KH |
940 | } |
941 | ||
69029cd5 | 942 | if (unlikely(!mm)) |
8697d331 | 943 | mm = &init_mm; |
accf163e | 944 | |
c05555b5 KH |
945 | if (page_is_file_cache(page)) |
946 | return mem_cgroup_charge_common(page, mm, gfp_mask, | |
e8589cc1 | 947 | MEM_CGROUP_CHARGE_TYPE_CACHE, NULL); |
c05555b5 KH |
948 | else |
949 | return mem_cgroup_charge_common(page, mm, gfp_mask, | |
950 | MEM_CGROUP_CHARGE_TYPE_SHMEM, NULL); | |
e8589cc1 KH |
951 | } |
952 | ||
8c7c6e34 KH |
953 | int mem_cgroup_try_charge_swapin(struct mm_struct *mm, |
954 | struct page *page, | |
955 | gfp_t mask, struct mem_cgroup **ptr) | |
956 | { | |
957 | struct mem_cgroup *mem; | |
958 | swp_entry_t ent; | |
959 | ||
f8d66542 | 960 | if (mem_cgroup_disabled()) |
8c7c6e34 KH |
961 | return 0; |
962 | ||
963 | if (!do_swap_account) | |
964 | goto charge_cur_mm; | |
965 | ||
966 | /* | |
967 | * A racing thread's fault, or swapoff, may have already updated | |
968 | * the pte, and even removed page from swap cache: return success | |
969 | * to go on to do_swap_page()'s pte_same() test, which should fail. | |
970 | */ | |
971 | if (!PageSwapCache(page)) | |
972 | return 0; | |
973 | ||
974 | ent.val = page_private(page); | |
975 | ||
976 | mem = lookup_swap_cgroup(ent); | |
977 | if (!mem || mem->obsolete) | |
978 | goto charge_cur_mm; | |
979 | *ptr = mem; | |
980 | return __mem_cgroup_try_charge(NULL, mask, ptr, true); | |
981 | charge_cur_mm: | |
982 | if (unlikely(!mm)) | |
983 | mm = &init_mm; | |
984 | return __mem_cgroup_try_charge(mm, mask, ptr, true); | |
985 | } | |
986 | ||
d13d1443 | 987 | #ifdef CONFIG_SWAP |
8c7c6e34 | 988 | |
d13d1443 KH |
989 | int mem_cgroup_cache_charge_swapin(struct page *page, |
990 | struct mm_struct *mm, gfp_t mask, bool locked) | |
991 | { | |
992 | int ret = 0; | |
993 | ||
f8d66542 | 994 | if (mem_cgroup_disabled()) |
d13d1443 KH |
995 | return 0; |
996 | if (unlikely(!mm)) | |
997 | mm = &init_mm; | |
998 | if (!locked) | |
999 | lock_page(page); | |
1000 | /* | |
1001 | * If not locked, the page can be dropped from SwapCache until | |
1002 | * we reach here. | |
1003 | */ | |
1004 | if (PageSwapCache(page)) { | |
8c7c6e34 KH |
1005 | struct mem_cgroup *mem = NULL; |
1006 | swp_entry_t ent; | |
1007 | ||
1008 | ent.val = page_private(page); | |
1009 | if (do_swap_account) { | |
1010 | mem = lookup_swap_cgroup(ent); | |
1011 | if (mem && mem->obsolete) | |
1012 | mem = NULL; | |
1013 | if (mem) | |
1014 | mm = NULL; | |
1015 | } | |
d13d1443 | 1016 | ret = mem_cgroup_charge_common(page, mm, mask, |
8c7c6e34 KH |
1017 | MEM_CGROUP_CHARGE_TYPE_SHMEM, mem); |
1018 | ||
1019 | if (!ret && do_swap_account) { | |
1020 | /* avoid double counting */ | |
1021 | mem = swap_cgroup_record(ent, NULL); | |
1022 | if (mem) { | |
1023 | res_counter_uncharge(&mem->memsw, PAGE_SIZE); | |
1024 | mem_cgroup_put(mem); | |
1025 | } | |
1026 | } | |
d13d1443 KH |
1027 | } |
1028 | if (!locked) | |
1029 | unlock_page(page); | |
08e552c6 KH |
1030 | /* add this page(page_cgroup) to the LRU we want. */ |
1031 | mem_cgroup_lru_fixup(page); | |
d13d1443 KH |
1032 | |
1033 | return ret; | |
1034 | } | |
1035 | #endif | |
1036 | ||
7a81b88c KH |
1037 | void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) |
1038 | { | |
1039 | struct page_cgroup *pc; | |
1040 | ||
f8d66542 | 1041 | if (mem_cgroup_disabled()) |
7a81b88c KH |
1042 | return; |
1043 | if (!ptr) | |
1044 | return; | |
1045 | pc = lookup_page_cgroup(page); | |
1046 | __mem_cgroup_commit_charge(ptr, pc, MEM_CGROUP_CHARGE_TYPE_MAPPED); | |
8c7c6e34 KH |
1047 | /* |
1048 | * Now swap is on-memory. This means this page may be | |
1049 | * counted both as mem and swap....double count. | |
1050 | * Fix it by uncharging from memsw. This SwapCache is stable | |
1051 | * because we're still under lock_page(). | |
1052 | */ | |
1053 | if (do_swap_account) { | |
1054 | swp_entry_t ent = {.val = page_private(page)}; | |
1055 | struct mem_cgroup *memcg; | |
1056 | memcg = swap_cgroup_record(ent, NULL); | |
1057 | if (memcg) { | |
1058 | /* If memcg is obsolete, memcg can be != ptr */ | |
1059 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); | |
1060 | mem_cgroup_put(memcg); | |
1061 | } | |
1062 | ||
1063 | } | |
08e552c6 KH |
1064 | /* add this page(page_cgroup) to the LRU we want. */ |
1065 | mem_cgroup_lru_fixup(page); | |
7a81b88c KH |
1066 | } |
1067 | ||
1068 | void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem) | |
1069 | { | |
f8d66542 | 1070 | if (mem_cgroup_disabled()) |
7a81b88c KH |
1071 | return; |
1072 | if (!mem) | |
1073 | return; | |
1074 | res_counter_uncharge(&mem->res, PAGE_SIZE); | |
8c7c6e34 KH |
1075 | if (do_swap_account) |
1076 | res_counter_uncharge(&mem->memsw, PAGE_SIZE); | |
7a81b88c KH |
1077 | css_put(&mem->css); |
1078 | } | |
1079 | ||
1080 | ||
8a9f3ccd | 1081 | /* |
69029cd5 | 1082 | * uncharge if !page_mapped(page) |
8a9f3ccd | 1083 | */ |
8c7c6e34 | 1084 | static struct mem_cgroup * |
69029cd5 | 1085 | __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) |
8a9f3ccd | 1086 | { |
8289546e | 1087 | struct page_cgroup *pc; |
8c7c6e34 | 1088 | struct mem_cgroup *mem = NULL; |
072c56c1 | 1089 | struct mem_cgroup_per_zone *mz; |
8a9f3ccd | 1090 | |
f8d66542 | 1091 | if (mem_cgroup_disabled()) |
8c7c6e34 | 1092 | return NULL; |
4077960e | 1093 | |
d13d1443 | 1094 | if (PageSwapCache(page)) |
8c7c6e34 | 1095 | return NULL; |
d13d1443 | 1096 | |
8697d331 | 1097 | /* |
3c541e14 | 1098 | * Check if our page_cgroup is valid |
8697d331 | 1099 | */ |
52d4b9ac KH |
1100 | pc = lookup_page_cgroup(page); |
1101 | if (unlikely(!pc || !PageCgroupUsed(pc))) | |
8c7c6e34 | 1102 | return NULL; |
b9c565d5 | 1103 | |
52d4b9ac | 1104 | lock_page_cgroup(pc); |
d13d1443 | 1105 | |
8c7c6e34 KH |
1106 | mem = pc->mem_cgroup; |
1107 | ||
d13d1443 KH |
1108 | if (!PageCgroupUsed(pc)) |
1109 | goto unlock_out; | |
1110 | ||
1111 | switch (ctype) { | |
1112 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
1113 | if (page_mapped(page)) | |
1114 | goto unlock_out; | |
1115 | break; | |
1116 | case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: | |
1117 | if (!PageAnon(page)) { /* Shared memory */ | |
1118 | if (page->mapping && !page_is_file_cache(page)) | |
1119 | goto unlock_out; | |
1120 | } else if (page_mapped(page)) /* Anon */ | |
1121 | goto unlock_out; | |
1122 | break; | |
1123 | default: | |
1124 | break; | |
52d4b9ac | 1125 | } |
d13d1443 | 1126 | |
8c7c6e34 KH |
1127 | res_counter_uncharge(&mem->res, PAGE_SIZE); |
1128 | if (do_swap_account && (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT)) | |
1129 | res_counter_uncharge(&mem->memsw, PAGE_SIZE); | |
1130 | ||
08e552c6 | 1131 | mem_cgroup_charge_statistics(mem, pc, false); |
52d4b9ac | 1132 | ClearPageCgroupUsed(pc); |
b9c565d5 | 1133 | |
69029cd5 | 1134 | mz = page_cgroup_zoneinfo(pc); |
52d4b9ac | 1135 | unlock_page_cgroup(pc); |
fb59e9f1 | 1136 | |
69029cd5 | 1137 | css_put(&mem->css); |
6d12e2d8 | 1138 | |
8c7c6e34 | 1139 | return mem; |
d13d1443 KH |
1140 | |
1141 | unlock_out: | |
1142 | unlock_page_cgroup(pc); | |
8c7c6e34 | 1143 | return NULL; |
3c541e14 BS |
1144 | } |
1145 | ||
69029cd5 KH |
1146 | void mem_cgroup_uncharge_page(struct page *page) |
1147 | { | |
52d4b9ac KH |
1148 | /* early check. */ |
1149 | if (page_mapped(page)) | |
1150 | return; | |
1151 | if (page->mapping && !PageAnon(page)) | |
1152 | return; | |
69029cd5 KH |
1153 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED); |
1154 | } | |
1155 | ||
1156 | void mem_cgroup_uncharge_cache_page(struct page *page) | |
1157 | { | |
1158 | VM_BUG_ON(page_mapped(page)); | |
b7abea96 | 1159 | VM_BUG_ON(page->mapping); |
69029cd5 KH |
1160 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); |
1161 | } | |
1162 | ||
8c7c6e34 KH |
1163 | /* |
1164 | * called from __delete_from_swap_cache() and drop "page" account. | |
1165 | * memcg information is recorded to swap_cgroup of "ent" | |
1166 | */ | |
1167 | void mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent) | |
1168 | { | |
1169 | struct mem_cgroup *memcg; | |
1170 | ||
1171 | memcg = __mem_cgroup_uncharge_common(page, | |
1172 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT); | |
1173 | /* record memcg information */ | |
1174 | if (do_swap_account && memcg) { | |
1175 | swap_cgroup_record(ent, memcg); | |
1176 | mem_cgroup_get(memcg); | |
1177 | } | |
1178 | } | |
1179 | ||
1180 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
1181 | /* | |
1182 | * called from swap_entry_free(). remove record in swap_cgroup and | |
1183 | * uncharge "memsw" account. | |
1184 | */ | |
1185 | void mem_cgroup_uncharge_swap(swp_entry_t ent) | |
d13d1443 | 1186 | { |
8c7c6e34 KH |
1187 | struct mem_cgroup *memcg; |
1188 | ||
1189 | if (!do_swap_account) | |
1190 | return; | |
1191 | ||
1192 | memcg = swap_cgroup_record(ent, NULL); | |
1193 | if (memcg) { | |
1194 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); | |
1195 | mem_cgroup_put(memcg); | |
1196 | } | |
d13d1443 | 1197 | } |
8c7c6e34 | 1198 | #endif |
d13d1443 | 1199 | |
ae41be37 | 1200 | /* |
01b1ae63 KH |
1201 | * Before starting migration, account PAGE_SIZE to mem_cgroup that the old |
1202 | * page belongs to. | |
ae41be37 | 1203 | */ |
01b1ae63 | 1204 | int mem_cgroup_prepare_migration(struct page *page, struct mem_cgroup **ptr) |
ae41be37 KH |
1205 | { |
1206 | struct page_cgroup *pc; | |
e8589cc1 | 1207 | struct mem_cgroup *mem = NULL; |
e8589cc1 | 1208 | int ret = 0; |
8869b8f6 | 1209 | |
f8d66542 | 1210 | if (mem_cgroup_disabled()) |
4077960e BS |
1211 | return 0; |
1212 | ||
52d4b9ac KH |
1213 | pc = lookup_page_cgroup(page); |
1214 | lock_page_cgroup(pc); | |
1215 | if (PageCgroupUsed(pc)) { | |
e8589cc1 KH |
1216 | mem = pc->mem_cgroup; |
1217 | css_get(&mem->css); | |
e8589cc1 | 1218 | } |
52d4b9ac | 1219 | unlock_page_cgroup(pc); |
01b1ae63 | 1220 | |
e8589cc1 | 1221 | if (mem) { |
01b1ae63 | 1222 | ret = mem_cgroup_try_charge(NULL, GFP_HIGHUSER_MOVABLE, &mem); |
e8589cc1 KH |
1223 | css_put(&mem->css); |
1224 | } | |
01b1ae63 | 1225 | *ptr = mem; |
e8589cc1 | 1226 | return ret; |
ae41be37 | 1227 | } |
8869b8f6 | 1228 | |
69029cd5 | 1229 | /* remove redundant charge if migration failed*/ |
01b1ae63 KH |
1230 | void mem_cgroup_end_migration(struct mem_cgroup *mem, |
1231 | struct page *oldpage, struct page *newpage) | |
ae41be37 | 1232 | { |
01b1ae63 KH |
1233 | struct page *target, *unused; |
1234 | struct page_cgroup *pc; | |
1235 | enum charge_type ctype; | |
1236 | ||
1237 | if (!mem) | |
1238 | return; | |
1239 | ||
1240 | /* at migration success, oldpage->mapping is NULL. */ | |
1241 | if (oldpage->mapping) { | |
1242 | target = oldpage; | |
1243 | unused = NULL; | |
1244 | } else { | |
1245 | target = newpage; | |
1246 | unused = oldpage; | |
1247 | } | |
1248 | ||
1249 | if (PageAnon(target)) | |
1250 | ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED; | |
1251 | else if (page_is_file_cache(target)) | |
1252 | ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; | |
1253 | else | |
1254 | ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; | |
1255 | ||
1256 | /* unused page is not on radix-tree now. */ | |
d13d1443 | 1257 | if (unused) |
01b1ae63 KH |
1258 | __mem_cgroup_uncharge_common(unused, ctype); |
1259 | ||
1260 | pc = lookup_page_cgroup(target); | |
69029cd5 | 1261 | /* |
01b1ae63 KH |
1262 | * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup. |
1263 | * So, double-counting is effectively avoided. | |
1264 | */ | |
1265 | __mem_cgroup_commit_charge(mem, pc, ctype); | |
1266 | ||
1267 | /* | |
1268 | * Both of oldpage and newpage are still under lock_page(). | |
1269 | * Then, we don't have to care about race in radix-tree. | |
1270 | * But we have to be careful that this page is unmapped or not. | |
1271 | * | |
1272 | * There is a case for !page_mapped(). At the start of | |
1273 | * migration, oldpage was mapped. But now, it's zapped. | |
1274 | * But we know *target* page is not freed/reused under us. | |
1275 | * mem_cgroup_uncharge_page() does all necessary checks. | |
69029cd5 | 1276 | */ |
01b1ae63 KH |
1277 | if (ctype == MEM_CGROUP_CHARGE_TYPE_MAPPED) |
1278 | mem_cgroup_uncharge_page(target); | |
ae41be37 | 1279 | } |
78fb7466 | 1280 | |
c9b0ed51 KH |
1281 | /* |
1282 | * A call to try to shrink memory usage under specified resource controller. | |
1283 | * This is typically used for page reclaiming for shmem for reducing side | |
1284 | * effect of page allocation from shmem, which is used by some mem_cgroup. | |
1285 | */ | |
1286 | int mem_cgroup_shrink_usage(struct mm_struct *mm, gfp_t gfp_mask) | |
1287 | { | |
1288 | struct mem_cgroup *mem; | |
1289 | int progress = 0; | |
1290 | int retry = MEM_CGROUP_RECLAIM_RETRIES; | |
1291 | ||
f8d66542 | 1292 | if (mem_cgroup_disabled()) |
cede86ac | 1293 | return 0; |
9623e078 HD |
1294 | if (!mm) |
1295 | return 0; | |
cede86ac | 1296 | |
c9b0ed51 KH |
1297 | rcu_read_lock(); |
1298 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
31a78f23 BS |
1299 | if (unlikely(!mem)) { |
1300 | rcu_read_unlock(); | |
1301 | return 0; | |
1302 | } | |
c9b0ed51 KH |
1303 | css_get(&mem->css); |
1304 | rcu_read_unlock(); | |
1305 | ||
1306 | do { | |
8c7c6e34 | 1307 | progress = try_to_free_mem_cgroup_pages(mem, gfp_mask, true); |
a10cebf5 | 1308 | progress += res_counter_check_under_limit(&mem->res); |
c9b0ed51 KH |
1309 | } while (!progress && --retry); |
1310 | ||
1311 | css_put(&mem->css); | |
1312 | if (!retry) | |
1313 | return -ENOMEM; | |
1314 | return 0; | |
1315 | } | |
1316 | ||
8c7c6e34 KH |
1317 | static DEFINE_MUTEX(set_limit_mutex); |
1318 | ||
d38d2a75 | 1319 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
8c7c6e34 | 1320 | unsigned long long val) |
628f4235 KH |
1321 | { |
1322 | ||
1323 | int retry_count = MEM_CGROUP_RECLAIM_RETRIES; | |
1324 | int progress; | |
8c7c6e34 | 1325 | u64 memswlimit; |
628f4235 KH |
1326 | int ret = 0; |
1327 | ||
8c7c6e34 | 1328 | while (retry_count) { |
628f4235 KH |
1329 | if (signal_pending(current)) { |
1330 | ret = -EINTR; | |
1331 | break; | |
1332 | } | |
8c7c6e34 KH |
1333 | /* |
1334 | * Rather than hide all in some function, I do this in | |
1335 | * open coded manner. You see what this really does. | |
1336 | * We have to guarantee mem->res.limit < mem->memsw.limit. | |
1337 | */ | |
1338 | mutex_lock(&set_limit_mutex); | |
1339 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
1340 | if (memswlimit < val) { | |
1341 | ret = -EINVAL; | |
1342 | mutex_unlock(&set_limit_mutex); | |
628f4235 KH |
1343 | break; |
1344 | } | |
8c7c6e34 KH |
1345 | ret = res_counter_set_limit(&memcg->res, val); |
1346 | mutex_unlock(&set_limit_mutex); | |
1347 | ||
1348 | if (!ret) | |
1349 | break; | |
1350 | ||
bced0520 | 1351 | progress = try_to_free_mem_cgroup_pages(memcg, |
8c7c6e34 KH |
1352 | GFP_HIGHUSER_MOVABLE, false); |
1353 | if (!progress) retry_count--; | |
1354 | } | |
1355 | return ret; | |
1356 | } | |
1357 | ||
1358 | int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, | |
1359 | unsigned long long val) | |
1360 | { | |
1361 | int retry_count = MEM_CGROUP_RECLAIM_RETRIES; | |
1362 | u64 memlimit, oldusage, curusage; | |
1363 | int ret; | |
1364 | ||
1365 | if (!do_swap_account) | |
1366 | return -EINVAL; | |
1367 | ||
1368 | while (retry_count) { | |
1369 | if (signal_pending(current)) { | |
1370 | ret = -EINTR; | |
1371 | break; | |
1372 | } | |
1373 | /* | |
1374 | * Rather than hide all in some function, I do this in | |
1375 | * open coded manner. You see what this really does. | |
1376 | * We have to guarantee mem->res.limit < mem->memsw.limit. | |
1377 | */ | |
1378 | mutex_lock(&set_limit_mutex); | |
1379 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
1380 | if (memlimit > val) { | |
1381 | ret = -EINVAL; | |
1382 | mutex_unlock(&set_limit_mutex); | |
1383 | break; | |
1384 | } | |
1385 | ret = res_counter_set_limit(&memcg->memsw, val); | |
1386 | mutex_unlock(&set_limit_mutex); | |
1387 | ||
1388 | if (!ret) | |
1389 | break; | |
1390 | ||
1391 | oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); | |
1392 | try_to_free_mem_cgroup_pages(memcg, GFP_HIGHUSER_MOVABLE, true); | |
1393 | curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); | |
1394 | if (curusage >= oldusage) | |
628f4235 KH |
1395 | retry_count--; |
1396 | } | |
1397 | return ret; | |
1398 | } | |
1399 | ||
cc847582 KH |
1400 | /* |
1401 | * This routine traverse page_cgroup in given list and drop them all. | |
cc847582 KH |
1402 | * *And* this routine doesn't reclaim page itself, just removes page_cgroup. |
1403 | */ | |
f817ed48 | 1404 | static int mem_cgroup_force_empty_list(struct mem_cgroup *mem, |
08e552c6 | 1405 | int node, int zid, enum lru_list lru) |
cc847582 | 1406 | { |
08e552c6 KH |
1407 | struct zone *zone; |
1408 | struct mem_cgroup_per_zone *mz; | |
f817ed48 | 1409 | struct page_cgroup *pc, *busy; |
08e552c6 | 1410 | unsigned long flags, loop; |
072c56c1 | 1411 | struct list_head *list; |
f817ed48 | 1412 | int ret = 0; |
072c56c1 | 1413 | |
08e552c6 KH |
1414 | zone = &NODE_DATA(node)->node_zones[zid]; |
1415 | mz = mem_cgroup_zoneinfo(mem, node, zid); | |
b69408e8 | 1416 | list = &mz->lists[lru]; |
cc847582 | 1417 | |
f817ed48 KH |
1418 | loop = MEM_CGROUP_ZSTAT(mz, lru); |
1419 | /* give some margin against EBUSY etc...*/ | |
1420 | loop += 256; | |
1421 | busy = NULL; | |
1422 | while (loop--) { | |
1423 | ret = 0; | |
08e552c6 | 1424 | spin_lock_irqsave(&zone->lru_lock, flags); |
f817ed48 | 1425 | if (list_empty(list)) { |
08e552c6 | 1426 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
52d4b9ac | 1427 | break; |
f817ed48 KH |
1428 | } |
1429 | pc = list_entry(list->prev, struct page_cgroup, lru); | |
1430 | if (busy == pc) { | |
1431 | list_move(&pc->lru, list); | |
1432 | busy = 0; | |
08e552c6 | 1433 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 KH |
1434 | continue; |
1435 | } | |
08e552c6 | 1436 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 KH |
1437 | |
1438 | ret = mem_cgroup_move_parent(pc, mem, GFP_HIGHUSER_MOVABLE); | |
1439 | if (ret == -ENOMEM) | |
52d4b9ac | 1440 | break; |
f817ed48 KH |
1441 | |
1442 | if (ret == -EBUSY || ret == -EINVAL) { | |
1443 | /* found lock contention or "pc" is obsolete. */ | |
1444 | busy = pc; | |
1445 | cond_resched(); | |
1446 | } else | |
1447 | busy = NULL; | |
cc847582 | 1448 | } |
08e552c6 | 1449 | |
f817ed48 KH |
1450 | if (!ret && !list_empty(list)) |
1451 | return -EBUSY; | |
1452 | return ret; | |
cc847582 KH |
1453 | } |
1454 | ||
1455 | /* | |
1456 | * make mem_cgroup's charge to be 0 if there is no task. | |
1457 | * This enables deleting this mem_cgroup. | |
1458 | */ | |
c1e862c1 | 1459 | static int mem_cgroup_force_empty(struct mem_cgroup *mem, bool free_all) |
cc847582 | 1460 | { |
f817ed48 KH |
1461 | int ret; |
1462 | int node, zid, shrink; | |
1463 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
c1e862c1 | 1464 | struct cgroup *cgrp = mem->css.cgroup; |
8869b8f6 | 1465 | |
cc847582 | 1466 | css_get(&mem->css); |
f817ed48 KH |
1467 | |
1468 | shrink = 0; | |
c1e862c1 KH |
1469 | /* should free all ? */ |
1470 | if (free_all) | |
1471 | goto try_to_free; | |
f817ed48 | 1472 | move_account: |
1ecaab2b | 1473 | while (mem->res.usage > 0) { |
f817ed48 | 1474 | ret = -EBUSY; |
c1e862c1 KH |
1475 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children)) |
1476 | goto out; | |
1477 | ret = -EINTR; | |
1478 | if (signal_pending(current)) | |
cc847582 | 1479 | goto out; |
52d4b9ac KH |
1480 | /* This is for making all *used* pages to be on LRU. */ |
1481 | lru_add_drain_all(); | |
f817ed48 KH |
1482 | ret = 0; |
1483 | for_each_node_state(node, N_POSSIBLE) { | |
1484 | for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { | |
b69408e8 | 1485 | enum lru_list l; |
f817ed48 KH |
1486 | for_each_lru(l) { |
1487 | ret = mem_cgroup_force_empty_list(mem, | |
08e552c6 | 1488 | node, zid, l); |
f817ed48 KH |
1489 | if (ret) |
1490 | break; | |
1491 | } | |
1ecaab2b | 1492 | } |
f817ed48 KH |
1493 | if (ret) |
1494 | break; | |
1495 | } | |
1496 | /* it seems parent cgroup doesn't have enough mem */ | |
1497 | if (ret == -ENOMEM) | |
1498 | goto try_to_free; | |
52d4b9ac | 1499 | cond_resched(); |
cc847582 KH |
1500 | } |
1501 | ret = 0; | |
1502 | out: | |
1503 | css_put(&mem->css); | |
1504 | return ret; | |
f817ed48 KH |
1505 | |
1506 | try_to_free: | |
c1e862c1 KH |
1507 | /* returns EBUSY if there is a task or if we come here twice. */ |
1508 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) { | |
f817ed48 KH |
1509 | ret = -EBUSY; |
1510 | goto out; | |
1511 | } | |
c1e862c1 KH |
1512 | /* we call try-to-free pages for make this cgroup empty */ |
1513 | lru_add_drain_all(); | |
f817ed48 KH |
1514 | /* try to free all pages in this cgroup */ |
1515 | shrink = 1; | |
1516 | while (nr_retries && mem->res.usage > 0) { | |
1517 | int progress; | |
c1e862c1 KH |
1518 | |
1519 | if (signal_pending(current)) { | |
1520 | ret = -EINTR; | |
1521 | goto out; | |
1522 | } | |
f817ed48 | 1523 | progress = try_to_free_mem_cgroup_pages(mem, |
8c7c6e34 | 1524 | GFP_HIGHUSER_MOVABLE, false); |
c1e862c1 | 1525 | if (!progress) { |
f817ed48 | 1526 | nr_retries--; |
c1e862c1 KH |
1527 | /* maybe some writeback is necessary */ |
1528 | congestion_wait(WRITE, HZ/10); | |
1529 | } | |
f817ed48 KH |
1530 | |
1531 | } | |
08e552c6 | 1532 | lru_add_drain(); |
f817ed48 KH |
1533 | /* try move_account...there may be some *locked* pages. */ |
1534 | if (mem->res.usage) | |
1535 | goto move_account; | |
1536 | ret = 0; | |
1537 | goto out; | |
cc847582 KH |
1538 | } |
1539 | ||
c1e862c1 KH |
1540 | int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event) |
1541 | { | |
1542 | return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true); | |
1543 | } | |
1544 | ||
1545 | ||
2c3daa72 | 1546 | static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) |
8cdea7c0 | 1547 | { |
8c7c6e34 KH |
1548 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
1549 | u64 val = 0; | |
1550 | int type, name; | |
1551 | ||
1552 | type = MEMFILE_TYPE(cft->private); | |
1553 | name = MEMFILE_ATTR(cft->private); | |
1554 | switch (type) { | |
1555 | case _MEM: | |
1556 | val = res_counter_read_u64(&mem->res, name); | |
1557 | break; | |
1558 | case _MEMSWAP: | |
1559 | if (do_swap_account) | |
1560 | val = res_counter_read_u64(&mem->memsw, name); | |
1561 | break; | |
1562 | default: | |
1563 | BUG(); | |
1564 | break; | |
1565 | } | |
1566 | return val; | |
8cdea7c0 | 1567 | } |
628f4235 KH |
1568 | /* |
1569 | * The user of this function is... | |
1570 | * RES_LIMIT. | |
1571 | */ | |
856c13aa PM |
1572 | static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, |
1573 | const char *buffer) | |
8cdea7c0 | 1574 | { |
628f4235 | 1575 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
8c7c6e34 | 1576 | int type, name; |
628f4235 KH |
1577 | unsigned long long val; |
1578 | int ret; | |
1579 | ||
8c7c6e34 KH |
1580 | type = MEMFILE_TYPE(cft->private); |
1581 | name = MEMFILE_ATTR(cft->private); | |
1582 | switch (name) { | |
628f4235 KH |
1583 | case RES_LIMIT: |
1584 | /* This function does all necessary parse...reuse it */ | |
1585 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
8c7c6e34 KH |
1586 | if (ret) |
1587 | break; | |
1588 | if (type == _MEM) | |
628f4235 | 1589 | ret = mem_cgroup_resize_limit(memcg, val); |
8c7c6e34 KH |
1590 | else |
1591 | ret = mem_cgroup_resize_memsw_limit(memcg, val); | |
628f4235 KH |
1592 | break; |
1593 | default: | |
1594 | ret = -EINVAL; /* should be BUG() ? */ | |
1595 | break; | |
1596 | } | |
1597 | return ret; | |
8cdea7c0 BS |
1598 | } |
1599 | ||
29f2a4da | 1600 | static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) |
c84872e1 PE |
1601 | { |
1602 | struct mem_cgroup *mem; | |
8c7c6e34 | 1603 | int type, name; |
c84872e1 PE |
1604 | |
1605 | mem = mem_cgroup_from_cont(cont); | |
8c7c6e34 KH |
1606 | type = MEMFILE_TYPE(event); |
1607 | name = MEMFILE_ATTR(event); | |
1608 | switch (name) { | |
29f2a4da | 1609 | case RES_MAX_USAGE: |
8c7c6e34 KH |
1610 | if (type == _MEM) |
1611 | res_counter_reset_max(&mem->res); | |
1612 | else | |
1613 | res_counter_reset_max(&mem->memsw); | |
29f2a4da PE |
1614 | break; |
1615 | case RES_FAILCNT: | |
8c7c6e34 KH |
1616 | if (type == _MEM) |
1617 | res_counter_reset_failcnt(&mem->res); | |
1618 | else | |
1619 | res_counter_reset_failcnt(&mem->memsw); | |
29f2a4da PE |
1620 | break; |
1621 | } | |
85cc59db | 1622 | return 0; |
c84872e1 PE |
1623 | } |
1624 | ||
d2ceb9b7 KH |
1625 | static const struct mem_cgroup_stat_desc { |
1626 | const char *msg; | |
1627 | u64 unit; | |
1628 | } mem_cgroup_stat_desc[] = { | |
1629 | [MEM_CGROUP_STAT_CACHE] = { "cache", PAGE_SIZE, }, | |
1630 | [MEM_CGROUP_STAT_RSS] = { "rss", PAGE_SIZE, }, | |
55e462b0 BR |
1631 | [MEM_CGROUP_STAT_PGPGIN_COUNT] = {"pgpgin", 1, }, |
1632 | [MEM_CGROUP_STAT_PGPGOUT_COUNT] = {"pgpgout", 1, }, | |
d2ceb9b7 KH |
1633 | }; |
1634 | ||
c64745cf PM |
1635 | static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, |
1636 | struct cgroup_map_cb *cb) | |
d2ceb9b7 | 1637 | { |
d2ceb9b7 KH |
1638 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); |
1639 | struct mem_cgroup_stat *stat = &mem_cont->stat; | |
1640 | int i; | |
1641 | ||
1642 | for (i = 0; i < ARRAY_SIZE(stat->cpustat[0].count); i++) { | |
1643 | s64 val; | |
1644 | ||
1645 | val = mem_cgroup_read_stat(stat, i); | |
1646 | val *= mem_cgroup_stat_desc[i].unit; | |
c64745cf | 1647 | cb->fill(cb, mem_cgroup_stat_desc[i].msg, val); |
d2ceb9b7 | 1648 | } |
6d12e2d8 KH |
1649 | /* showing # of active pages */ |
1650 | { | |
4f98a2fe RR |
1651 | unsigned long active_anon, inactive_anon; |
1652 | unsigned long active_file, inactive_file; | |
7b854121 | 1653 | unsigned long unevictable; |
4f98a2fe RR |
1654 | |
1655 | inactive_anon = mem_cgroup_get_all_zonestat(mem_cont, | |
1656 | LRU_INACTIVE_ANON); | |
1657 | active_anon = mem_cgroup_get_all_zonestat(mem_cont, | |
1658 | LRU_ACTIVE_ANON); | |
1659 | inactive_file = mem_cgroup_get_all_zonestat(mem_cont, | |
1660 | LRU_INACTIVE_FILE); | |
1661 | active_file = mem_cgroup_get_all_zonestat(mem_cont, | |
1662 | LRU_ACTIVE_FILE); | |
7b854121 LS |
1663 | unevictable = mem_cgroup_get_all_zonestat(mem_cont, |
1664 | LRU_UNEVICTABLE); | |
1665 | ||
4f98a2fe RR |
1666 | cb->fill(cb, "active_anon", (active_anon) * PAGE_SIZE); |
1667 | cb->fill(cb, "inactive_anon", (inactive_anon) * PAGE_SIZE); | |
1668 | cb->fill(cb, "active_file", (active_file) * PAGE_SIZE); | |
1669 | cb->fill(cb, "inactive_file", (inactive_file) * PAGE_SIZE); | |
7b854121 LS |
1670 | cb->fill(cb, "unevictable", unevictable * PAGE_SIZE); |
1671 | ||
6d12e2d8 | 1672 | } |
d2ceb9b7 KH |
1673 | return 0; |
1674 | } | |
1675 | ||
c1e862c1 | 1676 | |
8cdea7c0 BS |
1677 | static struct cftype mem_cgroup_files[] = { |
1678 | { | |
0eea1030 | 1679 | .name = "usage_in_bytes", |
8c7c6e34 | 1680 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
2c3daa72 | 1681 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 1682 | }, |
c84872e1 PE |
1683 | { |
1684 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 1685 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
29f2a4da | 1686 | .trigger = mem_cgroup_reset, |
c84872e1 PE |
1687 | .read_u64 = mem_cgroup_read, |
1688 | }, | |
8cdea7c0 | 1689 | { |
0eea1030 | 1690 | .name = "limit_in_bytes", |
8c7c6e34 | 1691 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
856c13aa | 1692 | .write_string = mem_cgroup_write, |
2c3daa72 | 1693 | .read_u64 = mem_cgroup_read, |
8cdea7c0 BS |
1694 | }, |
1695 | { | |
1696 | .name = "failcnt", | |
8c7c6e34 | 1697 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
29f2a4da | 1698 | .trigger = mem_cgroup_reset, |
2c3daa72 | 1699 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 1700 | }, |
d2ceb9b7 KH |
1701 | { |
1702 | .name = "stat", | |
c64745cf | 1703 | .read_map = mem_control_stat_show, |
d2ceb9b7 | 1704 | }, |
c1e862c1 KH |
1705 | { |
1706 | .name = "force_empty", | |
1707 | .trigger = mem_cgroup_force_empty_write, | |
1708 | }, | |
8cdea7c0 BS |
1709 | }; |
1710 | ||
8c7c6e34 KH |
1711 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
1712 | static struct cftype memsw_cgroup_files[] = { | |
1713 | { | |
1714 | .name = "memsw.usage_in_bytes", | |
1715 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
1716 | .read_u64 = mem_cgroup_read, | |
1717 | }, | |
1718 | { | |
1719 | .name = "memsw.max_usage_in_bytes", | |
1720 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
1721 | .trigger = mem_cgroup_reset, | |
1722 | .read_u64 = mem_cgroup_read, | |
1723 | }, | |
1724 | { | |
1725 | .name = "memsw.limit_in_bytes", | |
1726 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
1727 | .write_string = mem_cgroup_write, | |
1728 | .read_u64 = mem_cgroup_read, | |
1729 | }, | |
1730 | { | |
1731 | .name = "memsw.failcnt", | |
1732 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
1733 | .trigger = mem_cgroup_reset, | |
1734 | .read_u64 = mem_cgroup_read, | |
1735 | }, | |
1736 | }; | |
1737 | ||
1738 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
1739 | { | |
1740 | if (!do_swap_account) | |
1741 | return 0; | |
1742 | return cgroup_add_files(cont, ss, memsw_cgroup_files, | |
1743 | ARRAY_SIZE(memsw_cgroup_files)); | |
1744 | }; | |
1745 | #else | |
1746 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
1747 | { | |
1748 | return 0; | |
1749 | } | |
1750 | #endif | |
1751 | ||
6d12e2d8 KH |
1752 | static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
1753 | { | |
1754 | struct mem_cgroup_per_node *pn; | |
1ecaab2b | 1755 | struct mem_cgroup_per_zone *mz; |
b69408e8 | 1756 | enum lru_list l; |
41e3355d | 1757 | int zone, tmp = node; |
1ecaab2b KH |
1758 | /* |
1759 | * This routine is called against possible nodes. | |
1760 | * But it's BUG to call kmalloc() against offline node. | |
1761 | * | |
1762 | * TODO: this routine can waste much memory for nodes which will | |
1763 | * never be onlined. It's better to use memory hotplug callback | |
1764 | * function. | |
1765 | */ | |
41e3355d KH |
1766 | if (!node_state(node, N_NORMAL_MEMORY)) |
1767 | tmp = -1; | |
1768 | pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, tmp); | |
6d12e2d8 KH |
1769 | if (!pn) |
1770 | return 1; | |
1ecaab2b | 1771 | |
6d12e2d8 KH |
1772 | mem->info.nodeinfo[node] = pn; |
1773 | memset(pn, 0, sizeof(*pn)); | |
1ecaab2b KH |
1774 | |
1775 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
1776 | mz = &pn->zoneinfo[zone]; | |
b69408e8 CL |
1777 | for_each_lru(l) |
1778 | INIT_LIST_HEAD(&mz->lists[l]); | |
1ecaab2b | 1779 | } |
6d12e2d8 KH |
1780 | return 0; |
1781 | } | |
1782 | ||
1ecaab2b KH |
1783 | static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
1784 | { | |
1785 | kfree(mem->info.nodeinfo[node]); | |
1786 | } | |
1787 | ||
c8dad2bb JB |
1788 | static int mem_cgroup_size(void) |
1789 | { | |
1790 | int cpustat_size = nr_cpu_ids * sizeof(struct mem_cgroup_stat_cpu); | |
1791 | return sizeof(struct mem_cgroup) + cpustat_size; | |
1792 | } | |
1793 | ||
33327948 KH |
1794 | static struct mem_cgroup *mem_cgroup_alloc(void) |
1795 | { | |
1796 | struct mem_cgroup *mem; | |
c8dad2bb | 1797 | int size = mem_cgroup_size(); |
33327948 | 1798 | |
c8dad2bb JB |
1799 | if (size < PAGE_SIZE) |
1800 | mem = kmalloc(size, GFP_KERNEL); | |
33327948 | 1801 | else |
c8dad2bb | 1802 | mem = vmalloc(size); |
33327948 KH |
1803 | |
1804 | if (mem) | |
c8dad2bb | 1805 | memset(mem, 0, size); |
33327948 KH |
1806 | return mem; |
1807 | } | |
1808 | ||
8c7c6e34 KH |
1809 | /* |
1810 | * At destroying mem_cgroup, references from swap_cgroup can remain. | |
1811 | * (scanning all at force_empty is too costly...) | |
1812 | * | |
1813 | * Instead of clearing all references at force_empty, we remember | |
1814 | * the number of reference from swap_cgroup and free mem_cgroup when | |
1815 | * it goes down to 0. | |
1816 | * | |
1817 | * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and | |
1818 | * entry which points to this memcg will be ignore at swapin. | |
1819 | * | |
1820 | * Removal of cgroup itself succeeds regardless of refs from swap. | |
1821 | */ | |
1822 | ||
33327948 KH |
1823 | static void mem_cgroup_free(struct mem_cgroup *mem) |
1824 | { | |
08e552c6 KH |
1825 | int node; |
1826 | ||
8c7c6e34 KH |
1827 | if (atomic_read(&mem->refcnt) > 0) |
1828 | return; | |
08e552c6 KH |
1829 | |
1830 | ||
1831 | for_each_node_state(node, N_POSSIBLE) | |
1832 | free_mem_cgroup_per_zone_info(mem, node); | |
1833 | ||
c8dad2bb | 1834 | if (mem_cgroup_size() < PAGE_SIZE) |
33327948 KH |
1835 | kfree(mem); |
1836 | else | |
1837 | vfree(mem); | |
1838 | } | |
1839 | ||
8c7c6e34 KH |
1840 | static void mem_cgroup_get(struct mem_cgroup *mem) |
1841 | { | |
1842 | atomic_inc(&mem->refcnt); | |
1843 | } | |
1844 | ||
1845 | static void mem_cgroup_put(struct mem_cgroup *mem) | |
1846 | { | |
1847 | if (atomic_dec_and_test(&mem->refcnt)) { | |
1848 | if (!mem->obsolete) | |
1849 | return; | |
1850 | mem_cgroup_free(mem); | |
1851 | } | |
1852 | } | |
1853 | ||
33327948 | 1854 | |
c077719b KH |
1855 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
1856 | static void __init enable_swap_cgroup(void) | |
1857 | { | |
f8d66542 | 1858 | if (!mem_cgroup_disabled() && really_do_swap_account) |
c077719b KH |
1859 | do_swap_account = 1; |
1860 | } | |
1861 | #else | |
1862 | static void __init enable_swap_cgroup(void) | |
1863 | { | |
1864 | } | |
1865 | #endif | |
1866 | ||
8cdea7c0 BS |
1867 | static struct cgroup_subsys_state * |
1868 | mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) | |
1869 | { | |
28dbc4b6 | 1870 | struct mem_cgroup *mem, *parent; |
6d12e2d8 | 1871 | int node; |
8cdea7c0 | 1872 | |
c8dad2bb JB |
1873 | mem = mem_cgroup_alloc(); |
1874 | if (!mem) | |
1875 | return ERR_PTR(-ENOMEM); | |
78fb7466 | 1876 | |
6d12e2d8 KH |
1877 | for_each_node_state(node, N_POSSIBLE) |
1878 | if (alloc_mem_cgroup_per_zone_info(mem, node)) | |
1879 | goto free_out; | |
c077719b | 1880 | /* root ? */ |
28dbc4b6 | 1881 | if (cont->parent == NULL) { |
c077719b | 1882 | enable_swap_cgroup(); |
28dbc4b6 BS |
1883 | parent = NULL; |
1884 | } else | |
1885 | parent = mem_cgroup_from_cont(cont->parent); | |
1886 | ||
1887 | res_counter_init(&mem->res, parent ? &parent->res : NULL); | |
1888 | res_counter_init(&mem->memsw, parent ? &parent->memsw : NULL); | |
1889 | ||
6d12e2d8 | 1890 | |
6d61ef40 BS |
1891 | mem->last_scanned_child = NULL; |
1892 | ||
8cdea7c0 | 1893 | return &mem->css; |
6d12e2d8 KH |
1894 | free_out: |
1895 | for_each_node_state(node, N_POSSIBLE) | |
1ecaab2b | 1896 | free_mem_cgroup_per_zone_info(mem, node); |
c8dad2bb | 1897 | mem_cgroup_free(mem); |
2dda81ca | 1898 | return ERR_PTR(-ENOMEM); |
8cdea7c0 BS |
1899 | } |
1900 | ||
df878fb0 KH |
1901 | static void mem_cgroup_pre_destroy(struct cgroup_subsys *ss, |
1902 | struct cgroup *cont) | |
1903 | { | |
1904 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); | |
8c7c6e34 | 1905 | mem->obsolete = 1; |
c1e862c1 | 1906 | mem_cgroup_force_empty(mem, false); |
df878fb0 KH |
1907 | } |
1908 | ||
8cdea7c0 BS |
1909 | static void mem_cgroup_destroy(struct cgroup_subsys *ss, |
1910 | struct cgroup *cont) | |
1911 | { | |
33327948 | 1912 | mem_cgroup_free(mem_cgroup_from_cont(cont)); |
8cdea7c0 BS |
1913 | } |
1914 | ||
1915 | static int mem_cgroup_populate(struct cgroup_subsys *ss, | |
1916 | struct cgroup *cont) | |
1917 | { | |
8c7c6e34 KH |
1918 | int ret; |
1919 | ||
1920 | ret = cgroup_add_files(cont, ss, mem_cgroup_files, | |
1921 | ARRAY_SIZE(mem_cgroup_files)); | |
1922 | ||
1923 | if (!ret) | |
1924 | ret = register_memsw_files(cont, ss); | |
1925 | return ret; | |
8cdea7c0 BS |
1926 | } |
1927 | ||
67e465a7 BS |
1928 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, |
1929 | struct cgroup *cont, | |
1930 | struct cgroup *old_cont, | |
1931 | struct task_struct *p) | |
1932 | { | |
1933 | struct mm_struct *mm; | |
1934 | struct mem_cgroup *mem, *old_mem; | |
1935 | ||
1936 | mm = get_task_mm(p); | |
1937 | if (mm == NULL) | |
1938 | return; | |
1939 | ||
1940 | mem = mem_cgroup_from_cont(cont); | |
1941 | old_mem = mem_cgroup_from_cont(old_cont); | |
1942 | ||
67e465a7 BS |
1943 | /* |
1944 | * Only thread group leaders are allowed to migrate, the mm_struct is | |
1945 | * in effect owned by the leader | |
1946 | */ | |
52ea27eb | 1947 | if (!thread_group_leader(p)) |
67e465a7 BS |
1948 | goto out; |
1949 | ||
67e465a7 BS |
1950 | out: |
1951 | mmput(mm); | |
67e465a7 BS |
1952 | } |
1953 | ||
8cdea7c0 BS |
1954 | struct cgroup_subsys mem_cgroup_subsys = { |
1955 | .name = "memory", | |
1956 | .subsys_id = mem_cgroup_subsys_id, | |
1957 | .create = mem_cgroup_create, | |
df878fb0 | 1958 | .pre_destroy = mem_cgroup_pre_destroy, |
8cdea7c0 BS |
1959 | .destroy = mem_cgroup_destroy, |
1960 | .populate = mem_cgroup_populate, | |
67e465a7 | 1961 | .attach = mem_cgroup_move_task, |
6d12e2d8 | 1962 | .early_init = 0, |
8cdea7c0 | 1963 | }; |
c077719b KH |
1964 | |
1965 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
1966 | ||
1967 | static int __init disable_swap_account(char *s) | |
1968 | { | |
1969 | really_do_swap_account = 0; | |
1970 | return 1; | |
1971 | } | |
1972 | __setup("noswapaccount", disable_swap_account); | |
1973 | #endif |