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8cdea7c0 BS |
1 | /* memcontrol.c - Memory Controller |
2 | * | |
3 | * Copyright IBM Corporation, 2007 | |
4 | * Author Balbir Singh <balbir@linux.vnet.ibm.com> | |
5 | * | |
78fb7466 PE |
6 | * Copyright 2007 OpenVZ SWsoft Inc |
7 | * Author: Pavel Emelianov <xemul@openvz.org> | |
8 | * | |
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> | |
e222432b | 30 | #include <linux/limits.h> |
8c7c6e34 | 31 | #include <linux/mutex.h> |
f64c3f54 | 32 | #include <linux/rbtree.h> |
b6ac57d5 | 33 | #include <linux/slab.h> |
66e1707b BS |
34 | #include <linux/swap.h> |
35 | #include <linux/spinlock.h> | |
36 | #include <linux/fs.h> | |
d2ceb9b7 | 37 | #include <linux/seq_file.h> |
33327948 | 38 | #include <linux/vmalloc.h> |
b69408e8 | 39 | #include <linux/mm_inline.h> |
52d4b9ac | 40 | #include <linux/page_cgroup.h> |
08e552c6 | 41 | #include "internal.h" |
8cdea7c0 | 42 | |
8697d331 BS |
43 | #include <asm/uaccess.h> |
44 | ||
a181b0e8 | 45 | struct cgroup_subsys mem_cgroup_subsys __read_mostly; |
a181b0e8 | 46 | #define MEM_CGROUP_RECLAIM_RETRIES 5 |
4b3bde4c | 47 | struct mem_cgroup *root_mem_cgroup __read_mostly; |
8cdea7c0 | 48 | |
c077719b | 49 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
338c8431 | 50 | /* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */ |
c077719b KH |
51 | int do_swap_account __read_mostly; |
52 | static int really_do_swap_account __initdata = 1; /* for remember boot option*/ | |
53 | #else | |
54 | #define do_swap_account (0) | |
55 | #endif | |
56 | ||
7f4d454d | 57 | static DEFINE_MUTEX(memcg_tasklist); /* can be hold under cgroup_mutex */ |
f64c3f54 | 58 | #define SOFTLIMIT_EVENTS_THRESH (1000) |
c077719b | 59 | |
d52aa412 KH |
60 | /* |
61 | * Statistics for memory cgroup. | |
62 | */ | |
63 | enum mem_cgroup_stat_index { | |
64 | /* | |
65 | * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss. | |
66 | */ | |
67 | MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */ | |
d69b042f BS |
68 | MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */ |
69 | MEM_CGROUP_STAT_MAPPED_FILE, /* # of pages charged as file rss */ | |
55e462b0 BR |
70 | MEM_CGROUP_STAT_PGPGIN_COUNT, /* # of pages paged in */ |
71 | MEM_CGROUP_STAT_PGPGOUT_COUNT, /* # of pages paged out */ | |
f64c3f54 | 72 | MEM_CGROUP_STAT_EVENTS, /* sum of pagein + pageout for internal use */ |
d52aa412 KH |
73 | |
74 | MEM_CGROUP_STAT_NSTATS, | |
75 | }; | |
76 | ||
77 | struct mem_cgroup_stat_cpu { | |
78 | s64 count[MEM_CGROUP_STAT_NSTATS]; | |
79 | } ____cacheline_aligned_in_smp; | |
80 | ||
81 | struct mem_cgroup_stat { | |
c8dad2bb | 82 | struct mem_cgroup_stat_cpu cpustat[0]; |
d52aa412 KH |
83 | }; |
84 | ||
f64c3f54 BS |
85 | static inline void |
86 | __mem_cgroup_stat_reset_safe(struct mem_cgroup_stat_cpu *stat, | |
87 | enum mem_cgroup_stat_index idx) | |
88 | { | |
89 | stat->count[idx] = 0; | |
90 | } | |
91 | ||
92 | static inline s64 | |
93 | __mem_cgroup_stat_read_local(struct mem_cgroup_stat_cpu *stat, | |
94 | enum mem_cgroup_stat_index idx) | |
95 | { | |
96 | return stat->count[idx]; | |
97 | } | |
98 | ||
d52aa412 KH |
99 | /* |
100 | * For accounting under irq disable, no need for increment preempt count. | |
101 | */ | |
addb9efe | 102 | static inline void __mem_cgroup_stat_add_safe(struct mem_cgroup_stat_cpu *stat, |
d52aa412 KH |
103 | enum mem_cgroup_stat_index idx, int val) |
104 | { | |
addb9efe | 105 | stat->count[idx] += val; |
d52aa412 KH |
106 | } |
107 | ||
108 | static s64 mem_cgroup_read_stat(struct mem_cgroup_stat *stat, | |
109 | enum mem_cgroup_stat_index idx) | |
110 | { | |
111 | int cpu; | |
112 | s64 ret = 0; | |
113 | for_each_possible_cpu(cpu) | |
114 | ret += stat->cpustat[cpu].count[idx]; | |
115 | return ret; | |
116 | } | |
117 | ||
04046e1a KH |
118 | static s64 mem_cgroup_local_usage(struct mem_cgroup_stat *stat) |
119 | { | |
120 | s64 ret; | |
121 | ||
122 | ret = mem_cgroup_read_stat(stat, MEM_CGROUP_STAT_CACHE); | |
123 | ret += mem_cgroup_read_stat(stat, MEM_CGROUP_STAT_RSS); | |
124 | return ret; | |
125 | } | |
126 | ||
6d12e2d8 KH |
127 | /* |
128 | * per-zone information in memory controller. | |
129 | */ | |
6d12e2d8 | 130 | struct mem_cgroup_per_zone { |
072c56c1 KH |
131 | /* |
132 | * spin_lock to protect the per cgroup LRU | |
133 | */ | |
b69408e8 CL |
134 | struct list_head lists[NR_LRU_LISTS]; |
135 | unsigned long count[NR_LRU_LISTS]; | |
3e2f41f1 KM |
136 | |
137 | struct zone_reclaim_stat reclaim_stat; | |
f64c3f54 BS |
138 | struct rb_node tree_node; /* RB tree node */ |
139 | unsigned long long usage_in_excess;/* Set to the value by which */ | |
140 | /* the soft limit is exceeded*/ | |
141 | bool on_tree; | |
6d12e2d8 KH |
142 | }; |
143 | /* Macro for accessing counter */ | |
144 | #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)]) | |
145 | ||
146 | struct mem_cgroup_per_node { | |
147 | struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES]; | |
148 | }; | |
149 | ||
150 | struct mem_cgroup_lru_info { | |
151 | struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES]; | |
152 | }; | |
153 | ||
f64c3f54 BS |
154 | /* |
155 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
156 | * their hierarchy representation | |
157 | */ | |
158 | ||
159 | struct mem_cgroup_tree_per_zone { | |
160 | struct rb_root rb_root; | |
161 | spinlock_t lock; | |
162 | }; | |
163 | ||
164 | struct mem_cgroup_tree_per_node { | |
165 | struct mem_cgroup_tree_per_zone rb_tree_per_zone[MAX_NR_ZONES]; | |
166 | }; | |
167 | ||
168 | struct mem_cgroup_tree { | |
169 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
170 | }; | |
171 | ||
172 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
173 | ||
8cdea7c0 BS |
174 | /* |
175 | * The memory controller data structure. The memory controller controls both | |
176 | * page cache and RSS per cgroup. We would eventually like to provide | |
177 | * statistics based on the statistics developed by Rik Van Riel for clock-pro, | |
178 | * to help the administrator determine what knobs to tune. | |
179 | * | |
180 | * TODO: Add a water mark for the memory controller. Reclaim will begin when | |
8a9f3ccd BS |
181 | * we hit the water mark. May be even add a low water mark, such that |
182 | * no reclaim occurs from a cgroup at it's low water mark, this is | |
183 | * a feature that will be implemented much later in the future. | |
8cdea7c0 BS |
184 | */ |
185 | struct mem_cgroup { | |
186 | struct cgroup_subsys_state css; | |
187 | /* | |
188 | * the counter to account for memory usage | |
189 | */ | |
190 | struct res_counter res; | |
8c7c6e34 KH |
191 | /* |
192 | * the counter to account for mem+swap usage. | |
193 | */ | |
194 | struct res_counter memsw; | |
78fb7466 PE |
195 | /* |
196 | * Per cgroup active and inactive list, similar to the | |
197 | * per zone LRU lists. | |
78fb7466 | 198 | */ |
6d12e2d8 | 199 | struct mem_cgroup_lru_info info; |
072c56c1 | 200 | |
2733c06a KM |
201 | /* |
202 | protect against reclaim related member. | |
203 | */ | |
204 | spinlock_t reclaim_param_lock; | |
205 | ||
6c48a1d0 | 206 | int prev_priority; /* for recording reclaim priority */ |
6d61ef40 BS |
207 | |
208 | /* | |
209 | * While reclaiming in a hiearchy, we cache the last child we | |
04046e1a | 210 | * reclaimed from. |
6d61ef40 | 211 | */ |
04046e1a | 212 | int last_scanned_child; |
18f59ea7 BS |
213 | /* |
214 | * Should the accounting and control be hierarchical, per subtree? | |
215 | */ | |
216 | bool use_hierarchy; | |
a636b327 | 217 | unsigned long last_oom_jiffies; |
8c7c6e34 | 218 | atomic_t refcnt; |
14797e23 | 219 | |
a7885eb8 KM |
220 | unsigned int swappiness; |
221 | ||
22a668d7 KH |
222 | /* set when res.limit == memsw.limit */ |
223 | bool memsw_is_minimum; | |
224 | ||
d52aa412 | 225 | /* |
c8dad2bb | 226 | * statistics. This must be placed at the end of memcg. |
d52aa412 KH |
227 | */ |
228 | struct mem_cgroup_stat stat; | |
8cdea7c0 BS |
229 | }; |
230 | ||
217bc319 KH |
231 | enum charge_type { |
232 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, | |
233 | MEM_CGROUP_CHARGE_TYPE_MAPPED, | |
4f98a2fe | 234 | MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ |
c05555b5 | 235 | MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ |
d13d1443 | 236 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
8a9478ca | 237 | MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ |
c05555b5 KH |
238 | NR_CHARGE_TYPE, |
239 | }; | |
240 | ||
52d4b9ac KH |
241 | /* only for here (for easy reading.) */ |
242 | #define PCGF_CACHE (1UL << PCG_CACHE) | |
243 | #define PCGF_USED (1UL << PCG_USED) | |
52d4b9ac | 244 | #define PCGF_LOCK (1UL << PCG_LOCK) |
4b3bde4c BS |
245 | /* Not used, but added here for completeness */ |
246 | #define PCGF_ACCT (1UL << PCG_ACCT) | |
217bc319 | 247 | |
8c7c6e34 KH |
248 | /* for encoding cft->private value on file */ |
249 | #define _MEM (0) | |
250 | #define _MEMSWAP (1) | |
251 | #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val)) | |
252 | #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff) | |
253 | #define MEMFILE_ATTR(val) ((val) & 0xffff) | |
254 | ||
255 | static void mem_cgroup_get(struct mem_cgroup *mem); | |
256 | static void mem_cgroup_put(struct mem_cgroup *mem); | |
7bcc1bb1 | 257 | static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem); |
8c7c6e34 | 258 | |
f64c3f54 BS |
259 | static struct mem_cgroup_per_zone * |
260 | mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid) | |
261 | { | |
262 | return &mem->info.nodeinfo[nid]->zoneinfo[zid]; | |
263 | } | |
264 | ||
265 | static struct mem_cgroup_per_zone * | |
266 | page_cgroup_zoneinfo(struct page_cgroup *pc) | |
267 | { | |
268 | struct mem_cgroup *mem = pc->mem_cgroup; | |
269 | int nid = page_cgroup_nid(pc); | |
270 | int zid = page_cgroup_zid(pc); | |
271 | ||
272 | if (!mem) | |
273 | return NULL; | |
274 | ||
275 | return mem_cgroup_zoneinfo(mem, nid, zid); | |
276 | } | |
277 | ||
278 | static struct mem_cgroup_tree_per_zone * | |
279 | soft_limit_tree_node_zone(int nid, int zid) | |
280 | { | |
281 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
282 | } | |
283 | ||
284 | static struct mem_cgroup_tree_per_zone * | |
285 | soft_limit_tree_from_page(struct page *page) | |
286 | { | |
287 | int nid = page_to_nid(page); | |
288 | int zid = page_zonenum(page); | |
289 | ||
290 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
291 | } | |
292 | ||
293 | static void | |
294 | mem_cgroup_insert_exceeded(struct mem_cgroup *mem, | |
295 | struct mem_cgroup_per_zone *mz, | |
296 | struct mem_cgroup_tree_per_zone *mctz) | |
297 | { | |
298 | struct rb_node **p = &mctz->rb_root.rb_node; | |
299 | struct rb_node *parent = NULL; | |
300 | struct mem_cgroup_per_zone *mz_node; | |
301 | ||
302 | if (mz->on_tree) | |
303 | return; | |
304 | ||
305 | mz->usage_in_excess = res_counter_soft_limit_excess(&mem->res); | |
306 | spin_lock(&mctz->lock); | |
307 | while (*p) { | |
308 | parent = *p; | |
309 | mz_node = rb_entry(parent, struct mem_cgroup_per_zone, | |
310 | tree_node); | |
311 | if (mz->usage_in_excess < mz_node->usage_in_excess) | |
312 | p = &(*p)->rb_left; | |
313 | /* | |
314 | * We can't avoid mem cgroups that are over their soft | |
315 | * limit by the same amount | |
316 | */ | |
317 | else if (mz->usage_in_excess >= mz_node->usage_in_excess) | |
318 | p = &(*p)->rb_right; | |
319 | } | |
320 | rb_link_node(&mz->tree_node, parent, p); | |
321 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
322 | mz->on_tree = true; | |
323 | spin_unlock(&mctz->lock); | |
324 | } | |
325 | ||
326 | static void | |
327 | mem_cgroup_remove_exceeded(struct mem_cgroup *mem, | |
328 | struct mem_cgroup_per_zone *mz, | |
329 | struct mem_cgroup_tree_per_zone *mctz) | |
330 | { | |
331 | spin_lock(&mctz->lock); | |
332 | rb_erase(&mz->tree_node, &mctz->rb_root); | |
333 | mz->on_tree = false; | |
334 | spin_unlock(&mctz->lock); | |
335 | } | |
336 | ||
337 | static bool mem_cgroup_soft_limit_check(struct mem_cgroup *mem) | |
338 | { | |
339 | bool ret = false; | |
340 | int cpu; | |
341 | s64 val; | |
342 | struct mem_cgroup_stat_cpu *cpustat; | |
343 | ||
344 | cpu = get_cpu(); | |
345 | cpustat = &mem->stat.cpustat[cpu]; | |
346 | val = __mem_cgroup_stat_read_local(cpustat, MEM_CGROUP_STAT_EVENTS); | |
347 | if (unlikely(val > SOFTLIMIT_EVENTS_THRESH)) { | |
348 | __mem_cgroup_stat_reset_safe(cpustat, MEM_CGROUP_STAT_EVENTS); | |
349 | ret = true; | |
350 | } | |
351 | put_cpu(); | |
352 | return ret; | |
353 | } | |
354 | ||
355 | static void mem_cgroup_update_tree(struct mem_cgroup *mem, struct page *page) | |
356 | { | |
357 | unsigned long long prev_usage_in_excess, new_usage_in_excess; | |
358 | bool updated_tree = false; | |
359 | struct mem_cgroup_per_zone *mz; | |
360 | struct mem_cgroup_tree_per_zone *mctz; | |
361 | ||
362 | mz = mem_cgroup_zoneinfo(mem, page_to_nid(page), page_zonenum(page)); | |
363 | mctz = soft_limit_tree_from_page(page); | |
364 | ||
365 | /* | |
366 | * We do updates in lazy mode, mem's are removed | |
367 | * lazily from the per-zone, per-node rb tree | |
368 | */ | |
369 | prev_usage_in_excess = mz->usage_in_excess; | |
370 | ||
371 | new_usage_in_excess = res_counter_soft_limit_excess(&mem->res); | |
372 | if (prev_usage_in_excess) { | |
373 | mem_cgroup_remove_exceeded(mem, mz, mctz); | |
374 | updated_tree = true; | |
375 | } | |
376 | if (!new_usage_in_excess) | |
377 | goto done; | |
378 | mem_cgroup_insert_exceeded(mem, mz, mctz); | |
379 | ||
380 | done: | |
381 | if (updated_tree) { | |
382 | spin_lock(&mctz->lock); | |
383 | mz->usage_in_excess = new_usage_in_excess; | |
384 | spin_unlock(&mctz->lock); | |
385 | } | |
386 | } | |
387 | ||
388 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *mem) | |
389 | { | |
390 | int node, zone; | |
391 | struct mem_cgroup_per_zone *mz; | |
392 | struct mem_cgroup_tree_per_zone *mctz; | |
393 | ||
394 | for_each_node_state(node, N_POSSIBLE) { | |
395 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
396 | mz = mem_cgroup_zoneinfo(mem, node, zone); | |
397 | mctz = soft_limit_tree_node_zone(node, zone); | |
398 | mem_cgroup_remove_exceeded(mem, mz, mctz); | |
399 | } | |
400 | } | |
401 | } | |
402 | ||
c05555b5 KH |
403 | static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, |
404 | struct page_cgroup *pc, | |
405 | bool charge) | |
d52aa412 KH |
406 | { |
407 | int val = (charge)? 1 : -1; | |
408 | struct mem_cgroup_stat *stat = &mem->stat; | |
addb9efe | 409 | struct mem_cgroup_stat_cpu *cpustat; |
08e552c6 | 410 | int cpu = get_cpu(); |
d52aa412 | 411 | |
08e552c6 | 412 | cpustat = &stat->cpustat[cpu]; |
c05555b5 | 413 | if (PageCgroupCache(pc)) |
addb9efe | 414 | __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_CACHE, val); |
d52aa412 | 415 | else |
addb9efe | 416 | __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_RSS, val); |
55e462b0 BR |
417 | |
418 | if (charge) | |
addb9efe | 419 | __mem_cgroup_stat_add_safe(cpustat, |
55e462b0 BR |
420 | MEM_CGROUP_STAT_PGPGIN_COUNT, 1); |
421 | else | |
addb9efe | 422 | __mem_cgroup_stat_add_safe(cpustat, |
55e462b0 | 423 | MEM_CGROUP_STAT_PGPGOUT_COUNT, 1); |
f64c3f54 | 424 | __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_EVENTS, 1); |
08e552c6 | 425 | put_cpu(); |
6d12e2d8 KH |
426 | } |
427 | ||
14067bb3 | 428 | static unsigned long mem_cgroup_get_local_zonestat(struct mem_cgroup *mem, |
b69408e8 | 429 | enum lru_list idx) |
6d12e2d8 KH |
430 | { |
431 | int nid, zid; | |
432 | struct mem_cgroup_per_zone *mz; | |
433 | u64 total = 0; | |
434 | ||
435 | for_each_online_node(nid) | |
436 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
437 | mz = mem_cgroup_zoneinfo(mem, nid, zid); | |
438 | total += MEM_CGROUP_ZSTAT(mz, idx); | |
439 | } | |
440 | return total; | |
d52aa412 KH |
441 | } |
442 | ||
d5b69e38 | 443 | static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) |
8cdea7c0 BS |
444 | { |
445 | return container_of(cgroup_subsys_state(cont, | |
446 | mem_cgroup_subsys_id), struct mem_cgroup, | |
447 | css); | |
448 | } | |
449 | ||
cf475ad2 | 450 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 451 | { |
31a78f23 BS |
452 | /* |
453 | * mm_update_next_owner() may clear mm->owner to NULL | |
454 | * if it races with swapoff, page migration, etc. | |
455 | * So this can be called with p == NULL. | |
456 | */ | |
457 | if (unlikely(!p)) | |
458 | return NULL; | |
459 | ||
78fb7466 PE |
460 | return container_of(task_subsys_state(p, mem_cgroup_subsys_id), |
461 | struct mem_cgroup, css); | |
462 | } | |
463 | ||
54595fe2 KH |
464 | static struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) |
465 | { | |
466 | struct mem_cgroup *mem = NULL; | |
0b7f569e KH |
467 | |
468 | if (!mm) | |
469 | return NULL; | |
54595fe2 KH |
470 | /* |
471 | * Because we have no locks, mm->owner's may be being moved to other | |
472 | * cgroup. We use css_tryget() here even if this looks | |
473 | * pessimistic (rather than adding locks here). | |
474 | */ | |
475 | rcu_read_lock(); | |
476 | do { | |
477 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
478 | if (unlikely(!mem)) | |
479 | break; | |
480 | } while (!css_tryget(&mem->css)); | |
481 | rcu_read_unlock(); | |
482 | return mem; | |
483 | } | |
484 | ||
14067bb3 KH |
485 | /* |
486 | * Call callback function against all cgroup under hierarchy tree. | |
487 | */ | |
488 | static int mem_cgroup_walk_tree(struct mem_cgroup *root, void *data, | |
489 | int (*func)(struct mem_cgroup *, void *)) | |
490 | { | |
491 | int found, ret, nextid; | |
492 | struct cgroup_subsys_state *css; | |
493 | struct mem_cgroup *mem; | |
494 | ||
495 | if (!root->use_hierarchy) | |
496 | return (*func)(root, data); | |
497 | ||
498 | nextid = 1; | |
499 | do { | |
500 | ret = 0; | |
501 | mem = NULL; | |
502 | ||
503 | rcu_read_lock(); | |
504 | css = css_get_next(&mem_cgroup_subsys, nextid, &root->css, | |
505 | &found); | |
506 | if (css && css_tryget(css)) | |
507 | mem = container_of(css, struct mem_cgroup, css); | |
508 | rcu_read_unlock(); | |
509 | ||
510 | if (mem) { | |
511 | ret = (*func)(mem, data); | |
512 | css_put(&mem->css); | |
513 | } | |
514 | nextid = found + 1; | |
515 | } while (!ret && css); | |
516 | ||
517 | return ret; | |
518 | } | |
519 | ||
4b3bde4c BS |
520 | static inline bool mem_cgroup_is_root(struct mem_cgroup *mem) |
521 | { | |
522 | return (mem == root_mem_cgroup); | |
523 | } | |
524 | ||
08e552c6 KH |
525 | /* |
526 | * Following LRU functions are allowed to be used without PCG_LOCK. | |
527 | * Operations are called by routine of global LRU independently from memcg. | |
528 | * What we have to take care of here is validness of pc->mem_cgroup. | |
529 | * | |
530 | * Changes to pc->mem_cgroup happens when | |
531 | * 1. charge | |
532 | * 2. moving account | |
533 | * In typical case, "charge" is done before add-to-lru. Exception is SwapCache. | |
534 | * It is added to LRU before charge. | |
535 | * If PCG_USED bit is not set, page_cgroup is not added to this private LRU. | |
536 | * When moving account, the page is not on LRU. It's isolated. | |
537 | */ | |
4f98a2fe | 538 | |
08e552c6 KH |
539 | void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru) |
540 | { | |
541 | struct page_cgroup *pc; | |
08e552c6 | 542 | struct mem_cgroup_per_zone *mz; |
6d12e2d8 | 543 | |
f8d66542 | 544 | if (mem_cgroup_disabled()) |
08e552c6 KH |
545 | return; |
546 | pc = lookup_page_cgroup(page); | |
547 | /* can happen while we handle swapcache. */ | |
4b3bde4c | 548 | if (!TestClearPageCgroupAcctLRU(pc)) |
08e552c6 | 549 | return; |
4b3bde4c | 550 | VM_BUG_ON(!pc->mem_cgroup); |
544122e5 KH |
551 | /* |
552 | * We don't check PCG_USED bit. It's cleared when the "page" is finally | |
553 | * removed from global LRU. | |
554 | */ | |
08e552c6 | 555 | mz = page_cgroup_zoneinfo(pc); |
b69408e8 | 556 | MEM_CGROUP_ZSTAT(mz, lru) -= 1; |
4b3bde4c BS |
557 | if (mem_cgroup_is_root(pc->mem_cgroup)) |
558 | return; | |
559 | VM_BUG_ON(list_empty(&pc->lru)); | |
08e552c6 KH |
560 | list_del_init(&pc->lru); |
561 | return; | |
6d12e2d8 KH |
562 | } |
563 | ||
08e552c6 | 564 | void mem_cgroup_del_lru(struct page *page) |
6d12e2d8 | 565 | { |
08e552c6 KH |
566 | mem_cgroup_del_lru_list(page, page_lru(page)); |
567 | } | |
b69408e8 | 568 | |
08e552c6 KH |
569 | void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru) |
570 | { | |
571 | struct mem_cgroup_per_zone *mz; | |
572 | struct page_cgroup *pc; | |
b69408e8 | 573 | |
f8d66542 | 574 | if (mem_cgroup_disabled()) |
08e552c6 | 575 | return; |
6d12e2d8 | 576 | |
08e552c6 | 577 | pc = lookup_page_cgroup(page); |
bd112db8 DN |
578 | /* |
579 | * Used bit is set without atomic ops but after smp_wmb(). | |
580 | * For making pc->mem_cgroup visible, insert smp_rmb() here. | |
581 | */ | |
08e552c6 | 582 | smp_rmb(); |
4b3bde4c BS |
583 | /* unused or root page is not rotated. */ |
584 | if (!PageCgroupUsed(pc) || mem_cgroup_is_root(pc->mem_cgroup)) | |
08e552c6 KH |
585 | return; |
586 | mz = page_cgroup_zoneinfo(pc); | |
587 | list_move(&pc->lru, &mz->lists[lru]); | |
6d12e2d8 KH |
588 | } |
589 | ||
08e552c6 | 590 | void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru) |
66e1707b | 591 | { |
08e552c6 KH |
592 | struct page_cgroup *pc; |
593 | struct mem_cgroup_per_zone *mz; | |
6d12e2d8 | 594 | |
f8d66542 | 595 | if (mem_cgroup_disabled()) |
08e552c6 KH |
596 | return; |
597 | pc = lookup_page_cgroup(page); | |
4b3bde4c | 598 | VM_BUG_ON(PageCgroupAcctLRU(pc)); |
bd112db8 DN |
599 | /* |
600 | * Used bit is set without atomic ops but after smp_wmb(). | |
601 | * For making pc->mem_cgroup visible, insert smp_rmb() here. | |
602 | */ | |
08e552c6 KH |
603 | smp_rmb(); |
604 | if (!PageCgroupUsed(pc)) | |
894bc310 | 605 | return; |
b69408e8 | 606 | |
08e552c6 | 607 | mz = page_cgroup_zoneinfo(pc); |
b69408e8 | 608 | MEM_CGROUP_ZSTAT(mz, lru) += 1; |
4b3bde4c BS |
609 | SetPageCgroupAcctLRU(pc); |
610 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
611 | return; | |
08e552c6 KH |
612 | list_add(&pc->lru, &mz->lists[lru]); |
613 | } | |
544122e5 | 614 | |
08e552c6 | 615 | /* |
544122e5 KH |
616 | * At handling SwapCache, pc->mem_cgroup may be changed while it's linked to |
617 | * lru because the page may.be reused after it's fully uncharged (because of | |
618 | * SwapCache behavior).To handle that, unlink page_cgroup from LRU when charge | |
619 | * it again. This function is only used to charge SwapCache. It's done under | |
620 | * lock_page and expected that zone->lru_lock is never held. | |
08e552c6 | 621 | */ |
544122e5 | 622 | static void mem_cgroup_lru_del_before_commit_swapcache(struct page *page) |
08e552c6 | 623 | { |
544122e5 KH |
624 | unsigned long flags; |
625 | struct zone *zone = page_zone(page); | |
626 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
627 | ||
628 | spin_lock_irqsave(&zone->lru_lock, flags); | |
629 | /* | |
630 | * Forget old LRU when this page_cgroup is *not* used. This Used bit | |
631 | * is guarded by lock_page() because the page is SwapCache. | |
632 | */ | |
633 | if (!PageCgroupUsed(pc)) | |
634 | mem_cgroup_del_lru_list(page, page_lru(page)); | |
635 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
08e552c6 KH |
636 | } |
637 | ||
544122e5 KH |
638 | static void mem_cgroup_lru_add_after_commit_swapcache(struct page *page) |
639 | { | |
640 | unsigned long flags; | |
641 | struct zone *zone = page_zone(page); | |
642 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
643 | ||
644 | spin_lock_irqsave(&zone->lru_lock, flags); | |
645 | /* link when the page is linked to LRU but page_cgroup isn't */ | |
4b3bde4c | 646 | if (PageLRU(page) && !PageCgroupAcctLRU(pc)) |
544122e5 KH |
647 | mem_cgroup_add_lru_list(page, page_lru(page)); |
648 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
649 | } | |
650 | ||
651 | ||
08e552c6 KH |
652 | void mem_cgroup_move_lists(struct page *page, |
653 | enum lru_list from, enum lru_list to) | |
654 | { | |
f8d66542 | 655 | if (mem_cgroup_disabled()) |
08e552c6 KH |
656 | return; |
657 | mem_cgroup_del_lru_list(page, from); | |
658 | mem_cgroup_add_lru_list(page, to); | |
66e1707b BS |
659 | } |
660 | ||
4c4a2214 DR |
661 | int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem) |
662 | { | |
663 | int ret; | |
0b7f569e | 664 | struct mem_cgroup *curr = NULL; |
4c4a2214 DR |
665 | |
666 | task_lock(task); | |
0b7f569e KH |
667 | rcu_read_lock(); |
668 | curr = try_get_mem_cgroup_from_mm(task->mm); | |
669 | rcu_read_unlock(); | |
4c4a2214 | 670 | task_unlock(task); |
0b7f569e KH |
671 | if (!curr) |
672 | return 0; | |
673 | if (curr->use_hierarchy) | |
674 | ret = css_is_ancestor(&curr->css, &mem->css); | |
675 | else | |
676 | ret = (curr == mem); | |
677 | css_put(&curr->css); | |
4c4a2214 DR |
678 | return ret; |
679 | } | |
680 | ||
6c48a1d0 KH |
681 | /* |
682 | * prev_priority control...this will be used in memory reclaim path. | |
683 | */ | |
684 | int mem_cgroup_get_reclaim_priority(struct mem_cgroup *mem) | |
685 | { | |
2733c06a KM |
686 | int prev_priority; |
687 | ||
688 | spin_lock(&mem->reclaim_param_lock); | |
689 | prev_priority = mem->prev_priority; | |
690 | spin_unlock(&mem->reclaim_param_lock); | |
691 | ||
692 | return prev_priority; | |
6c48a1d0 KH |
693 | } |
694 | ||
695 | void mem_cgroup_note_reclaim_priority(struct mem_cgroup *mem, int priority) | |
696 | { | |
2733c06a | 697 | spin_lock(&mem->reclaim_param_lock); |
6c48a1d0 KH |
698 | if (priority < mem->prev_priority) |
699 | mem->prev_priority = priority; | |
2733c06a | 700 | spin_unlock(&mem->reclaim_param_lock); |
6c48a1d0 KH |
701 | } |
702 | ||
703 | void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, int priority) | |
704 | { | |
2733c06a | 705 | spin_lock(&mem->reclaim_param_lock); |
6c48a1d0 | 706 | mem->prev_priority = priority; |
2733c06a | 707 | spin_unlock(&mem->reclaim_param_lock); |
6c48a1d0 KH |
708 | } |
709 | ||
c772be93 | 710 | static int calc_inactive_ratio(struct mem_cgroup *memcg, unsigned long *present_pages) |
14797e23 KM |
711 | { |
712 | unsigned long active; | |
713 | unsigned long inactive; | |
c772be93 KM |
714 | unsigned long gb; |
715 | unsigned long inactive_ratio; | |
14797e23 | 716 | |
14067bb3 KH |
717 | inactive = mem_cgroup_get_local_zonestat(memcg, LRU_INACTIVE_ANON); |
718 | active = mem_cgroup_get_local_zonestat(memcg, LRU_ACTIVE_ANON); | |
14797e23 | 719 | |
c772be93 KM |
720 | gb = (inactive + active) >> (30 - PAGE_SHIFT); |
721 | if (gb) | |
722 | inactive_ratio = int_sqrt(10 * gb); | |
723 | else | |
724 | inactive_ratio = 1; | |
725 | ||
726 | if (present_pages) { | |
727 | present_pages[0] = inactive; | |
728 | present_pages[1] = active; | |
729 | } | |
730 | ||
731 | return inactive_ratio; | |
732 | } | |
733 | ||
734 | int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg) | |
735 | { | |
736 | unsigned long active; | |
737 | unsigned long inactive; | |
738 | unsigned long present_pages[2]; | |
739 | unsigned long inactive_ratio; | |
740 | ||
741 | inactive_ratio = calc_inactive_ratio(memcg, present_pages); | |
742 | ||
743 | inactive = present_pages[0]; | |
744 | active = present_pages[1]; | |
745 | ||
746 | if (inactive * inactive_ratio < active) | |
14797e23 KM |
747 | return 1; |
748 | ||
749 | return 0; | |
750 | } | |
751 | ||
56e49d21 RR |
752 | int mem_cgroup_inactive_file_is_low(struct mem_cgroup *memcg) |
753 | { | |
754 | unsigned long active; | |
755 | unsigned long inactive; | |
756 | ||
757 | inactive = mem_cgroup_get_local_zonestat(memcg, LRU_INACTIVE_FILE); | |
758 | active = mem_cgroup_get_local_zonestat(memcg, LRU_ACTIVE_FILE); | |
759 | ||
760 | return (active > inactive); | |
761 | } | |
762 | ||
a3d8e054 KM |
763 | unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup *memcg, |
764 | struct zone *zone, | |
765 | enum lru_list lru) | |
766 | { | |
767 | int nid = zone->zone_pgdat->node_id; | |
768 | int zid = zone_idx(zone); | |
769 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
770 | ||
771 | return MEM_CGROUP_ZSTAT(mz, lru); | |
772 | } | |
773 | ||
3e2f41f1 KM |
774 | struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg, |
775 | struct zone *zone) | |
776 | { | |
777 | int nid = zone->zone_pgdat->node_id; | |
778 | int zid = zone_idx(zone); | |
779 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
780 | ||
781 | return &mz->reclaim_stat; | |
782 | } | |
783 | ||
784 | struct zone_reclaim_stat * | |
785 | mem_cgroup_get_reclaim_stat_from_page(struct page *page) | |
786 | { | |
787 | struct page_cgroup *pc; | |
788 | struct mem_cgroup_per_zone *mz; | |
789 | ||
790 | if (mem_cgroup_disabled()) | |
791 | return NULL; | |
792 | ||
793 | pc = lookup_page_cgroup(page); | |
bd112db8 DN |
794 | /* |
795 | * Used bit is set without atomic ops but after smp_wmb(). | |
796 | * For making pc->mem_cgroup visible, insert smp_rmb() here. | |
797 | */ | |
798 | smp_rmb(); | |
799 | if (!PageCgroupUsed(pc)) | |
800 | return NULL; | |
801 | ||
3e2f41f1 KM |
802 | mz = page_cgroup_zoneinfo(pc); |
803 | if (!mz) | |
804 | return NULL; | |
805 | ||
806 | return &mz->reclaim_stat; | |
807 | } | |
808 | ||
66e1707b BS |
809 | unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, |
810 | struct list_head *dst, | |
811 | unsigned long *scanned, int order, | |
812 | int mode, struct zone *z, | |
813 | struct mem_cgroup *mem_cont, | |
4f98a2fe | 814 | int active, int file) |
66e1707b BS |
815 | { |
816 | unsigned long nr_taken = 0; | |
817 | struct page *page; | |
818 | unsigned long scan; | |
819 | LIST_HEAD(pc_list); | |
820 | struct list_head *src; | |
ff7283fa | 821 | struct page_cgroup *pc, *tmp; |
1ecaab2b KH |
822 | int nid = z->zone_pgdat->node_id; |
823 | int zid = zone_idx(z); | |
824 | struct mem_cgroup_per_zone *mz; | |
b7c46d15 | 825 | int lru = LRU_FILE * file + active; |
2ffebca6 | 826 | int ret; |
66e1707b | 827 | |
cf475ad2 | 828 | BUG_ON(!mem_cont); |
1ecaab2b | 829 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); |
b69408e8 | 830 | src = &mz->lists[lru]; |
66e1707b | 831 | |
ff7283fa KH |
832 | scan = 0; |
833 | list_for_each_entry_safe_reverse(pc, tmp, src, lru) { | |
436c6541 | 834 | if (scan >= nr_to_scan) |
ff7283fa | 835 | break; |
08e552c6 KH |
836 | |
837 | page = pc->page; | |
52d4b9ac KH |
838 | if (unlikely(!PageCgroupUsed(pc))) |
839 | continue; | |
436c6541 | 840 | if (unlikely(!PageLRU(page))) |
ff7283fa | 841 | continue; |
ff7283fa | 842 | |
436c6541 | 843 | scan++; |
2ffebca6 KH |
844 | ret = __isolate_lru_page(page, mode, file); |
845 | switch (ret) { | |
846 | case 0: | |
66e1707b | 847 | list_move(&page->lru, dst); |
2ffebca6 | 848 | mem_cgroup_del_lru(page); |
66e1707b | 849 | nr_taken++; |
2ffebca6 KH |
850 | break; |
851 | case -EBUSY: | |
852 | /* we don't affect global LRU but rotate in our LRU */ | |
853 | mem_cgroup_rotate_lru_list(page, page_lru(page)); | |
854 | break; | |
855 | default: | |
856 | break; | |
66e1707b BS |
857 | } |
858 | } | |
859 | ||
66e1707b BS |
860 | *scanned = scan; |
861 | return nr_taken; | |
862 | } | |
863 | ||
6d61ef40 BS |
864 | #define mem_cgroup_from_res_counter(counter, member) \ |
865 | container_of(counter, struct mem_cgroup, member) | |
866 | ||
b85a96c0 DN |
867 | static bool mem_cgroup_check_under_limit(struct mem_cgroup *mem) |
868 | { | |
869 | if (do_swap_account) { | |
870 | if (res_counter_check_under_limit(&mem->res) && | |
871 | res_counter_check_under_limit(&mem->memsw)) | |
872 | return true; | |
873 | } else | |
874 | if (res_counter_check_under_limit(&mem->res)) | |
875 | return true; | |
876 | return false; | |
877 | } | |
878 | ||
a7885eb8 KM |
879 | static unsigned int get_swappiness(struct mem_cgroup *memcg) |
880 | { | |
881 | struct cgroup *cgrp = memcg->css.cgroup; | |
882 | unsigned int swappiness; | |
883 | ||
884 | /* root ? */ | |
885 | if (cgrp->parent == NULL) | |
886 | return vm_swappiness; | |
887 | ||
888 | spin_lock(&memcg->reclaim_param_lock); | |
889 | swappiness = memcg->swappiness; | |
890 | spin_unlock(&memcg->reclaim_param_lock); | |
891 | ||
892 | return swappiness; | |
893 | } | |
894 | ||
81d39c20 KH |
895 | static int mem_cgroup_count_children_cb(struct mem_cgroup *mem, void *data) |
896 | { | |
897 | int *val = data; | |
898 | (*val)++; | |
899 | return 0; | |
900 | } | |
e222432b BS |
901 | |
902 | /** | |
903 | * mem_cgroup_print_mem_info: Called from OOM with tasklist_lock held in read mode. | |
904 | * @memcg: The memory cgroup that went over limit | |
905 | * @p: Task that is going to be killed | |
906 | * | |
907 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
908 | * enabled | |
909 | */ | |
910 | void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) | |
911 | { | |
912 | struct cgroup *task_cgrp; | |
913 | struct cgroup *mem_cgrp; | |
914 | /* | |
915 | * Need a buffer in BSS, can't rely on allocations. The code relies | |
916 | * on the assumption that OOM is serialized for memory controller. | |
917 | * If this assumption is broken, revisit this code. | |
918 | */ | |
919 | static char memcg_name[PATH_MAX]; | |
920 | int ret; | |
921 | ||
922 | if (!memcg) | |
923 | return; | |
924 | ||
925 | ||
926 | rcu_read_lock(); | |
927 | ||
928 | mem_cgrp = memcg->css.cgroup; | |
929 | task_cgrp = task_cgroup(p, mem_cgroup_subsys_id); | |
930 | ||
931 | ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX); | |
932 | if (ret < 0) { | |
933 | /* | |
934 | * Unfortunately, we are unable to convert to a useful name | |
935 | * But we'll still print out the usage information | |
936 | */ | |
937 | rcu_read_unlock(); | |
938 | goto done; | |
939 | } | |
940 | rcu_read_unlock(); | |
941 | ||
942 | printk(KERN_INFO "Task in %s killed", memcg_name); | |
943 | ||
944 | rcu_read_lock(); | |
945 | ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX); | |
946 | if (ret < 0) { | |
947 | rcu_read_unlock(); | |
948 | goto done; | |
949 | } | |
950 | rcu_read_unlock(); | |
951 | ||
952 | /* | |
953 | * Continues from above, so we don't need an KERN_ level | |
954 | */ | |
955 | printk(KERN_CONT " as a result of limit of %s\n", memcg_name); | |
956 | done: | |
957 | ||
958 | printk(KERN_INFO "memory: usage %llukB, limit %llukB, failcnt %llu\n", | |
959 | res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, | |
960 | res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, | |
961 | res_counter_read_u64(&memcg->res, RES_FAILCNT)); | |
962 | printk(KERN_INFO "memory+swap: usage %llukB, limit %llukB, " | |
963 | "failcnt %llu\n", | |
964 | res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, | |
965 | res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, | |
966 | res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); | |
967 | } | |
968 | ||
81d39c20 KH |
969 | /* |
970 | * This function returns the number of memcg under hierarchy tree. Returns | |
971 | * 1(self count) if no children. | |
972 | */ | |
973 | static int mem_cgroup_count_children(struct mem_cgroup *mem) | |
974 | { | |
975 | int num = 0; | |
976 | mem_cgroup_walk_tree(mem, &num, mem_cgroup_count_children_cb); | |
977 | return num; | |
978 | } | |
979 | ||
6d61ef40 | 980 | /* |
04046e1a KH |
981 | * Visit the first child (need not be the first child as per the ordering |
982 | * of the cgroup list, since we track last_scanned_child) of @mem and use | |
983 | * that to reclaim free pages from. | |
984 | */ | |
985 | static struct mem_cgroup * | |
986 | mem_cgroup_select_victim(struct mem_cgroup *root_mem) | |
987 | { | |
988 | struct mem_cgroup *ret = NULL; | |
989 | struct cgroup_subsys_state *css; | |
990 | int nextid, found; | |
991 | ||
992 | if (!root_mem->use_hierarchy) { | |
993 | css_get(&root_mem->css); | |
994 | ret = root_mem; | |
995 | } | |
996 | ||
997 | while (!ret) { | |
998 | rcu_read_lock(); | |
999 | nextid = root_mem->last_scanned_child + 1; | |
1000 | css = css_get_next(&mem_cgroup_subsys, nextid, &root_mem->css, | |
1001 | &found); | |
1002 | if (css && css_tryget(css)) | |
1003 | ret = container_of(css, struct mem_cgroup, css); | |
1004 | ||
1005 | rcu_read_unlock(); | |
1006 | /* Updates scanning parameter */ | |
1007 | spin_lock(&root_mem->reclaim_param_lock); | |
1008 | if (!css) { | |
1009 | /* this means start scan from ID:1 */ | |
1010 | root_mem->last_scanned_child = 0; | |
1011 | } else | |
1012 | root_mem->last_scanned_child = found; | |
1013 | spin_unlock(&root_mem->reclaim_param_lock); | |
1014 | } | |
1015 | ||
1016 | return ret; | |
1017 | } | |
1018 | ||
1019 | /* | |
1020 | * Scan the hierarchy if needed to reclaim memory. We remember the last child | |
1021 | * we reclaimed from, so that we don't end up penalizing one child extensively | |
1022 | * based on its position in the children list. | |
6d61ef40 BS |
1023 | * |
1024 | * root_mem is the original ancestor that we've been reclaim from. | |
04046e1a KH |
1025 | * |
1026 | * We give up and return to the caller when we visit root_mem twice. | |
1027 | * (other groups can be removed while we're walking....) | |
81d39c20 KH |
1028 | * |
1029 | * If shrink==true, for avoiding to free too much, this returns immedieately. | |
6d61ef40 BS |
1030 | */ |
1031 | static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, | |
81d39c20 | 1032 | gfp_t gfp_mask, bool noswap, bool shrink) |
6d61ef40 | 1033 | { |
04046e1a KH |
1034 | struct mem_cgroup *victim; |
1035 | int ret, total = 0; | |
1036 | int loop = 0; | |
1037 | ||
22a668d7 KH |
1038 | /* If memsw_is_minimum==1, swap-out is of-no-use. */ |
1039 | if (root_mem->memsw_is_minimum) | |
1040 | noswap = true; | |
1041 | ||
04046e1a KH |
1042 | while (loop < 2) { |
1043 | victim = mem_cgroup_select_victim(root_mem); | |
1044 | if (victim == root_mem) | |
1045 | loop++; | |
1046 | if (!mem_cgroup_local_usage(&victim->stat)) { | |
1047 | /* this cgroup's local usage == 0 */ | |
1048 | css_put(&victim->css); | |
6d61ef40 BS |
1049 | continue; |
1050 | } | |
04046e1a KH |
1051 | /* we use swappiness of local cgroup */ |
1052 | ret = try_to_free_mem_cgroup_pages(victim, gfp_mask, noswap, | |
1053 | get_swappiness(victim)); | |
1054 | css_put(&victim->css); | |
81d39c20 KH |
1055 | /* |
1056 | * At shrinking usage, we can't check we should stop here or | |
1057 | * reclaim more. It's depends on callers. last_scanned_child | |
1058 | * will work enough for keeping fairness under tree. | |
1059 | */ | |
1060 | if (shrink) | |
1061 | return ret; | |
04046e1a | 1062 | total += ret; |
b85a96c0 | 1063 | if (mem_cgroup_check_under_limit(root_mem)) |
04046e1a | 1064 | return 1 + total; |
6d61ef40 | 1065 | } |
04046e1a | 1066 | return total; |
6d61ef40 BS |
1067 | } |
1068 | ||
a636b327 KH |
1069 | bool mem_cgroup_oom_called(struct task_struct *task) |
1070 | { | |
1071 | bool ret = false; | |
1072 | struct mem_cgroup *mem; | |
1073 | struct mm_struct *mm; | |
1074 | ||
1075 | rcu_read_lock(); | |
1076 | mm = task->mm; | |
1077 | if (!mm) | |
1078 | mm = &init_mm; | |
1079 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
1080 | if (mem && time_before(jiffies, mem->last_oom_jiffies + HZ/10)) | |
1081 | ret = true; | |
1082 | rcu_read_unlock(); | |
1083 | return ret; | |
1084 | } | |
0b7f569e KH |
1085 | |
1086 | static int record_last_oom_cb(struct mem_cgroup *mem, void *data) | |
1087 | { | |
1088 | mem->last_oom_jiffies = jiffies; | |
1089 | return 0; | |
1090 | } | |
1091 | ||
1092 | static void record_last_oom(struct mem_cgroup *mem) | |
1093 | { | |
1094 | mem_cgroup_walk_tree(mem, NULL, record_last_oom_cb); | |
1095 | } | |
1096 | ||
d69b042f BS |
1097 | /* |
1098 | * Currently used to update mapped file statistics, but the routine can be | |
1099 | * generalized to update other statistics as well. | |
1100 | */ | |
1101 | void mem_cgroup_update_mapped_file_stat(struct page *page, int val) | |
1102 | { | |
1103 | struct mem_cgroup *mem; | |
1104 | struct mem_cgroup_stat *stat; | |
1105 | struct mem_cgroup_stat_cpu *cpustat; | |
1106 | int cpu; | |
1107 | struct page_cgroup *pc; | |
1108 | ||
1109 | if (!page_is_file_cache(page)) | |
1110 | return; | |
1111 | ||
1112 | pc = lookup_page_cgroup(page); | |
1113 | if (unlikely(!pc)) | |
1114 | return; | |
1115 | ||
1116 | lock_page_cgroup(pc); | |
1117 | mem = pc->mem_cgroup; | |
1118 | if (!mem) | |
1119 | goto done; | |
1120 | ||
1121 | if (!PageCgroupUsed(pc)) | |
1122 | goto done; | |
1123 | ||
1124 | /* | |
1125 | * Preemption is already disabled, we don't need get_cpu() | |
1126 | */ | |
1127 | cpu = smp_processor_id(); | |
1128 | stat = &mem->stat; | |
1129 | cpustat = &stat->cpustat[cpu]; | |
1130 | ||
1131 | __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_MAPPED_FILE, val); | |
1132 | done: | |
1133 | unlock_page_cgroup(pc); | |
1134 | } | |
0b7f569e | 1135 | |
f817ed48 KH |
1136 | /* |
1137 | * Unlike exported interface, "oom" parameter is added. if oom==true, | |
1138 | * oom-killer can be invoked. | |
8a9f3ccd | 1139 | */ |
f817ed48 | 1140 | static int __mem_cgroup_try_charge(struct mm_struct *mm, |
8c7c6e34 | 1141 | gfp_t gfp_mask, struct mem_cgroup **memcg, |
f64c3f54 | 1142 | bool oom, struct page *page) |
8a9f3ccd | 1143 | { |
f64c3f54 | 1144 | struct mem_cgroup *mem, *mem_over_limit, *mem_over_soft_limit; |
7a81b88c | 1145 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; |
f64c3f54 | 1146 | struct res_counter *fail_res, *soft_fail_res = NULL; |
a636b327 KH |
1147 | |
1148 | if (unlikely(test_thread_flag(TIF_MEMDIE))) { | |
1149 | /* Don't account this! */ | |
1150 | *memcg = NULL; | |
1151 | return 0; | |
1152 | } | |
1153 | ||
8a9f3ccd | 1154 | /* |
3be91277 HD |
1155 | * We always charge the cgroup the mm_struct belongs to. |
1156 | * The mm_struct's mem_cgroup changes on task migration if the | |
8a9f3ccd BS |
1157 | * thread group leader migrates. It's possible that mm is not |
1158 | * set, if so charge the init_mm (happens for pagecache usage). | |
1159 | */ | |
54595fe2 KH |
1160 | mem = *memcg; |
1161 | if (likely(!mem)) { | |
1162 | mem = try_get_mem_cgroup_from_mm(mm); | |
7a81b88c | 1163 | *memcg = mem; |
e8589cc1 | 1164 | } else { |
7a81b88c | 1165 | css_get(&mem->css); |
e8589cc1 | 1166 | } |
54595fe2 KH |
1167 | if (unlikely(!mem)) |
1168 | return 0; | |
1169 | ||
46f7e602 | 1170 | VM_BUG_ON(css_is_removed(&mem->css)); |
8a9f3ccd | 1171 | |
8c7c6e34 KH |
1172 | while (1) { |
1173 | int ret; | |
1174 | bool noswap = false; | |
7a81b88c | 1175 | |
f64c3f54 BS |
1176 | ret = res_counter_charge(&mem->res, PAGE_SIZE, &fail_res, |
1177 | &soft_fail_res); | |
8c7c6e34 KH |
1178 | if (likely(!ret)) { |
1179 | if (!do_swap_account) | |
1180 | break; | |
28dbc4b6 | 1181 | ret = res_counter_charge(&mem->memsw, PAGE_SIZE, |
f64c3f54 | 1182 | &fail_res, NULL); |
8c7c6e34 KH |
1183 | if (likely(!ret)) |
1184 | break; | |
1185 | /* mem+swap counter fails */ | |
f64c3f54 | 1186 | res_counter_uncharge(&mem->res, PAGE_SIZE, NULL); |
8c7c6e34 | 1187 | noswap = true; |
6d61ef40 BS |
1188 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, |
1189 | memsw); | |
1190 | } else | |
1191 | /* mem counter fails */ | |
1192 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, | |
1193 | res); | |
1194 | ||
3be91277 | 1195 | if (!(gfp_mask & __GFP_WAIT)) |
7a81b88c | 1196 | goto nomem; |
e1a1cd59 | 1197 | |
6d61ef40 | 1198 | ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, gfp_mask, |
81d39c20 | 1199 | noswap, false); |
4d1c6273 DN |
1200 | if (ret) |
1201 | continue; | |
66e1707b BS |
1202 | |
1203 | /* | |
8869b8f6 HD |
1204 | * try_to_free_mem_cgroup_pages() might not give us a full |
1205 | * picture of reclaim. Some pages are reclaimed and might be | |
1206 | * moved to swap cache or just unmapped from the cgroup. | |
1207 | * Check the limit again to see if the reclaim reduced the | |
1208 | * current usage of the cgroup before giving up | |
8c7c6e34 | 1209 | * |
8869b8f6 | 1210 | */ |
b85a96c0 DN |
1211 | if (mem_cgroup_check_under_limit(mem_over_limit)) |
1212 | continue; | |
3be91277 HD |
1213 | |
1214 | if (!nr_retries--) { | |
a636b327 | 1215 | if (oom) { |
7f4d454d | 1216 | mutex_lock(&memcg_tasklist); |
88700756 | 1217 | mem_cgroup_out_of_memory(mem_over_limit, gfp_mask); |
7f4d454d | 1218 | mutex_unlock(&memcg_tasklist); |
0b7f569e | 1219 | record_last_oom(mem_over_limit); |
a636b327 | 1220 | } |
7a81b88c | 1221 | goto nomem; |
66e1707b | 1222 | } |
8a9f3ccd | 1223 | } |
f64c3f54 BS |
1224 | /* |
1225 | * Insert just the ancestor, we should trickle down to the correct | |
1226 | * cgroup for reclaim, since the other nodes will be below their | |
1227 | * soft limit | |
1228 | */ | |
1229 | if (soft_fail_res) { | |
1230 | mem_over_soft_limit = | |
1231 | mem_cgroup_from_res_counter(soft_fail_res, res); | |
1232 | if (mem_cgroup_soft_limit_check(mem_over_soft_limit)) | |
1233 | mem_cgroup_update_tree(mem_over_soft_limit, page); | |
1234 | } | |
7a81b88c KH |
1235 | return 0; |
1236 | nomem: | |
1237 | css_put(&mem->css); | |
1238 | return -ENOMEM; | |
1239 | } | |
8a9f3ccd | 1240 | |
a3b2d692 KH |
1241 | /* |
1242 | * A helper function to get mem_cgroup from ID. must be called under | |
1243 | * rcu_read_lock(). The caller must check css_is_removed() or some if | |
1244 | * it's concern. (dropping refcnt from swap can be called against removed | |
1245 | * memcg.) | |
1246 | */ | |
1247 | static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) | |
1248 | { | |
1249 | struct cgroup_subsys_state *css; | |
1250 | ||
1251 | /* ID 0 is unused ID */ | |
1252 | if (!id) | |
1253 | return NULL; | |
1254 | css = css_lookup(&mem_cgroup_subsys, id); | |
1255 | if (!css) | |
1256 | return NULL; | |
1257 | return container_of(css, struct mem_cgroup, css); | |
1258 | } | |
1259 | ||
b5a84319 KH |
1260 | static struct mem_cgroup *try_get_mem_cgroup_from_swapcache(struct page *page) |
1261 | { | |
1262 | struct mem_cgroup *mem; | |
3c776e64 | 1263 | struct page_cgroup *pc; |
a3b2d692 | 1264 | unsigned short id; |
b5a84319 KH |
1265 | swp_entry_t ent; |
1266 | ||
3c776e64 DN |
1267 | VM_BUG_ON(!PageLocked(page)); |
1268 | ||
b5a84319 KH |
1269 | if (!PageSwapCache(page)) |
1270 | return NULL; | |
1271 | ||
3c776e64 | 1272 | pc = lookup_page_cgroup(page); |
c0bd3f63 | 1273 | lock_page_cgroup(pc); |
a3b2d692 | 1274 | if (PageCgroupUsed(pc)) { |
3c776e64 | 1275 | mem = pc->mem_cgroup; |
a3b2d692 KH |
1276 | if (mem && !css_tryget(&mem->css)) |
1277 | mem = NULL; | |
1278 | } else { | |
3c776e64 | 1279 | ent.val = page_private(page); |
a3b2d692 KH |
1280 | id = lookup_swap_cgroup(ent); |
1281 | rcu_read_lock(); | |
1282 | mem = mem_cgroup_lookup(id); | |
1283 | if (mem && !css_tryget(&mem->css)) | |
1284 | mem = NULL; | |
1285 | rcu_read_unlock(); | |
3c776e64 | 1286 | } |
c0bd3f63 | 1287 | unlock_page_cgroup(pc); |
b5a84319 KH |
1288 | return mem; |
1289 | } | |
1290 | ||
7a81b88c | 1291 | /* |
a5e924f5 | 1292 | * commit a charge got by __mem_cgroup_try_charge() and makes page_cgroup to be |
7a81b88c KH |
1293 | * USED state. If already USED, uncharge and return. |
1294 | */ | |
1295 | ||
1296 | static void __mem_cgroup_commit_charge(struct mem_cgroup *mem, | |
1297 | struct page_cgroup *pc, | |
1298 | enum charge_type ctype) | |
1299 | { | |
7a81b88c KH |
1300 | /* try_charge() can return NULL to *memcg, taking care of it. */ |
1301 | if (!mem) | |
1302 | return; | |
52d4b9ac KH |
1303 | |
1304 | lock_page_cgroup(pc); | |
1305 | if (unlikely(PageCgroupUsed(pc))) { | |
1306 | unlock_page_cgroup(pc); | |
f64c3f54 | 1307 | res_counter_uncharge(&mem->res, PAGE_SIZE, NULL); |
8c7c6e34 | 1308 | if (do_swap_account) |
f64c3f54 | 1309 | res_counter_uncharge(&mem->memsw, PAGE_SIZE, NULL); |
52d4b9ac | 1310 | css_put(&mem->css); |
7a81b88c | 1311 | return; |
52d4b9ac | 1312 | } |
4b3bde4c | 1313 | |
8a9f3ccd | 1314 | pc->mem_cgroup = mem; |
261fb61a KH |
1315 | /* |
1316 | * We access a page_cgroup asynchronously without lock_page_cgroup(). | |
1317 | * Especially when a page_cgroup is taken from a page, pc->mem_cgroup | |
1318 | * is accessed after testing USED bit. To make pc->mem_cgroup visible | |
1319 | * before USED bit, we need memory barrier here. | |
1320 | * See mem_cgroup_add_lru_list(), etc. | |
1321 | */ | |
08e552c6 | 1322 | smp_wmb(); |
4b3bde4c BS |
1323 | switch (ctype) { |
1324 | case MEM_CGROUP_CHARGE_TYPE_CACHE: | |
1325 | case MEM_CGROUP_CHARGE_TYPE_SHMEM: | |
1326 | SetPageCgroupCache(pc); | |
1327 | SetPageCgroupUsed(pc); | |
1328 | break; | |
1329 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
1330 | ClearPageCgroupCache(pc); | |
1331 | SetPageCgroupUsed(pc); | |
1332 | break; | |
1333 | default: | |
1334 | break; | |
1335 | } | |
3be91277 | 1336 | |
08e552c6 | 1337 | mem_cgroup_charge_statistics(mem, pc, true); |
52d4b9ac | 1338 | |
52d4b9ac | 1339 | unlock_page_cgroup(pc); |
7a81b88c | 1340 | } |
66e1707b | 1341 | |
f817ed48 KH |
1342 | /** |
1343 | * mem_cgroup_move_account - move account of the page | |
1344 | * @pc: page_cgroup of the page. | |
1345 | * @from: mem_cgroup which the page is moved from. | |
1346 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
1347 | * | |
1348 | * The caller must confirm following. | |
08e552c6 | 1349 | * - page is not on LRU (isolate_page() is useful.) |
f817ed48 KH |
1350 | * |
1351 | * returns 0 at success, | |
1352 | * returns -EBUSY when lock is busy or "pc" is unstable. | |
1353 | * | |
1354 | * This function does "uncharge" from old cgroup but doesn't do "charge" to | |
1355 | * new cgroup. It should be done by a caller. | |
1356 | */ | |
1357 | ||
1358 | static int mem_cgroup_move_account(struct page_cgroup *pc, | |
1359 | struct mem_cgroup *from, struct mem_cgroup *to) | |
1360 | { | |
1361 | struct mem_cgroup_per_zone *from_mz, *to_mz; | |
1362 | int nid, zid; | |
1363 | int ret = -EBUSY; | |
d69b042f BS |
1364 | struct page *page; |
1365 | int cpu; | |
1366 | struct mem_cgroup_stat *stat; | |
1367 | struct mem_cgroup_stat_cpu *cpustat; | |
f817ed48 | 1368 | |
f817ed48 | 1369 | VM_BUG_ON(from == to); |
08e552c6 | 1370 | VM_BUG_ON(PageLRU(pc->page)); |
f817ed48 KH |
1371 | |
1372 | nid = page_cgroup_nid(pc); | |
1373 | zid = page_cgroup_zid(pc); | |
1374 | from_mz = mem_cgroup_zoneinfo(from, nid, zid); | |
1375 | to_mz = mem_cgroup_zoneinfo(to, nid, zid); | |
1376 | ||
f817ed48 KH |
1377 | if (!trylock_page_cgroup(pc)) |
1378 | return ret; | |
1379 | ||
1380 | if (!PageCgroupUsed(pc)) | |
1381 | goto out; | |
1382 | ||
1383 | if (pc->mem_cgroup != from) | |
1384 | goto out; | |
1385 | ||
f64c3f54 | 1386 | res_counter_uncharge(&from->res, PAGE_SIZE, NULL); |
08e552c6 | 1387 | mem_cgroup_charge_statistics(from, pc, false); |
d69b042f BS |
1388 | |
1389 | page = pc->page; | |
1390 | if (page_is_file_cache(page) && page_mapped(page)) { | |
1391 | cpu = smp_processor_id(); | |
1392 | /* Update mapped_file data for mem_cgroup "from" */ | |
1393 | stat = &from->stat; | |
1394 | cpustat = &stat->cpustat[cpu]; | |
1395 | __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_MAPPED_FILE, | |
1396 | -1); | |
1397 | ||
1398 | /* Update mapped_file data for mem_cgroup "to" */ | |
1399 | stat = &to->stat; | |
1400 | cpustat = &stat->cpustat[cpu]; | |
1401 | __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_MAPPED_FILE, | |
1402 | 1); | |
1403 | } | |
1404 | ||
08e552c6 | 1405 | if (do_swap_account) |
f64c3f54 | 1406 | res_counter_uncharge(&from->memsw, PAGE_SIZE, NULL); |
40d58138 DN |
1407 | css_put(&from->css); |
1408 | ||
1409 | css_get(&to->css); | |
08e552c6 KH |
1410 | pc->mem_cgroup = to; |
1411 | mem_cgroup_charge_statistics(to, pc, true); | |
08e552c6 | 1412 | ret = 0; |
f817ed48 KH |
1413 | out: |
1414 | unlock_page_cgroup(pc); | |
88703267 KH |
1415 | /* |
1416 | * We charges against "to" which may not have any tasks. Then, "to" | |
1417 | * can be under rmdir(). But in current implementation, caller of | |
1418 | * this function is just force_empty() and it's garanteed that | |
1419 | * "to" is never removed. So, we don't check rmdir status here. | |
1420 | */ | |
f817ed48 KH |
1421 | return ret; |
1422 | } | |
1423 | ||
1424 | /* | |
1425 | * move charges to its parent. | |
1426 | */ | |
1427 | ||
1428 | static int mem_cgroup_move_parent(struct page_cgroup *pc, | |
1429 | struct mem_cgroup *child, | |
1430 | gfp_t gfp_mask) | |
1431 | { | |
08e552c6 | 1432 | struct page *page = pc->page; |
f817ed48 KH |
1433 | struct cgroup *cg = child->css.cgroup; |
1434 | struct cgroup *pcg = cg->parent; | |
1435 | struct mem_cgroup *parent; | |
f817ed48 KH |
1436 | int ret; |
1437 | ||
1438 | /* Is ROOT ? */ | |
1439 | if (!pcg) | |
1440 | return -EINVAL; | |
1441 | ||
08e552c6 | 1442 | |
f817ed48 KH |
1443 | parent = mem_cgroup_from_cont(pcg); |
1444 | ||
08e552c6 | 1445 | |
f64c3f54 | 1446 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false, page); |
a636b327 | 1447 | if (ret || !parent) |
f817ed48 KH |
1448 | return ret; |
1449 | ||
40d58138 DN |
1450 | if (!get_page_unless_zero(page)) { |
1451 | ret = -EBUSY; | |
1452 | goto uncharge; | |
1453 | } | |
08e552c6 KH |
1454 | |
1455 | ret = isolate_lru_page(page); | |
1456 | ||
1457 | if (ret) | |
1458 | goto cancel; | |
f817ed48 | 1459 | |
f817ed48 | 1460 | ret = mem_cgroup_move_account(pc, child, parent); |
f817ed48 | 1461 | |
08e552c6 KH |
1462 | putback_lru_page(page); |
1463 | if (!ret) { | |
1464 | put_page(page); | |
40d58138 DN |
1465 | /* drop extra refcnt by try_charge() */ |
1466 | css_put(&parent->css); | |
08e552c6 | 1467 | return 0; |
8c7c6e34 | 1468 | } |
40d58138 | 1469 | |
08e552c6 | 1470 | cancel: |
40d58138 DN |
1471 | put_page(page); |
1472 | uncharge: | |
1473 | /* drop extra refcnt by try_charge() */ | |
1474 | css_put(&parent->css); | |
1475 | /* uncharge if move fails */ | |
f64c3f54 | 1476 | res_counter_uncharge(&parent->res, PAGE_SIZE, NULL); |
08e552c6 | 1477 | if (do_swap_account) |
f64c3f54 | 1478 | res_counter_uncharge(&parent->memsw, PAGE_SIZE, NULL); |
f817ed48 KH |
1479 | return ret; |
1480 | } | |
1481 | ||
7a81b88c KH |
1482 | /* |
1483 | * Charge the memory controller for page usage. | |
1484 | * Return | |
1485 | * 0 if the charge was successful | |
1486 | * < 0 if the cgroup is over its limit | |
1487 | */ | |
1488 | static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, | |
1489 | gfp_t gfp_mask, enum charge_type ctype, | |
1490 | struct mem_cgroup *memcg) | |
1491 | { | |
1492 | struct mem_cgroup *mem; | |
1493 | struct page_cgroup *pc; | |
1494 | int ret; | |
1495 | ||
1496 | pc = lookup_page_cgroup(page); | |
1497 | /* can happen at boot */ | |
1498 | if (unlikely(!pc)) | |
1499 | return 0; | |
1500 | prefetchw(pc); | |
1501 | ||
1502 | mem = memcg; | |
f64c3f54 | 1503 | ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, true, page); |
a636b327 | 1504 | if (ret || !mem) |
7a81b88c KH |
1505 | return ret; |
1506 | ||
1507 | __mem_cgroup_commit_charge(mem, pc, ctype); | |
8a9f3ccd | 1508 | return 0; |
8a9f3ccd BS |
1509 | } |
1510 | ||
7a81b88c KH |
1511 | int mem_cgroup_newpage_charge(struct page *page, |
1512 | struct mm_struct *mm, gfp_t gfp_mask) | |
217bc319 | 1513 | { |
f8d66542 | 1514 | if (mem_cgroup_disabled()) |
cede86ac | 1515 | return 0; |
52d4b9ac KH |
1516 | if (PageCompound(page)) |
1517 | return 0; | |
69029cd5 KH |
1518 | /* |
1519 | * If already mapped, we don't have to account. | |
1520 | * If page cache, page->mapping has address_space. | |
1521 | * But page->mapping may have out-of-use anon_vma pointer, | |
1522 | * detecit it by PageAnon() check. newly-mapped-anon's page->mapping | |
1523 | * is NULL. | |
1524 | */ | |
1525 | if (page_mapped(page) || (page->mapping && !PageAnon(page))) | |
1526 | return 0; | |
1527 | if (unlikely(!mm)) | |
1528 | mm = &init_mm; | |
217bc319 | 1529 | return mem_cgroup_charge_common(page, mm, gfp_mask, |
e8589cc1 | 1530 | MEM_CGROUP_CHARGE_TYPE_MAPPED, NULL); |
217bc319 KH |
1531 | } |
1532 | ||
83aae4c7 DN |
1533 | static void |
1534 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
1535 | enum charge_type ctype); | |
1536 | ||
e1a1cd59 BS |
1537 | int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, |
1538 | gfp_t gfp_mask) | |
8697d331 | 1539 | { |
b5a84319 KH |
1540 | struct mem_cgroup *mem = NULL; |
1541 | int ret; | |
1542 | ||
f8d66542 | 1543 | if (mem_cgroup_disabled()) |
cede86ac | 1544 | return 0; |
52d4b9ac KH |
1545 | if (PageCompound(page)) |
1546 | return 0; | |
accf163e KH |
1547 | /* |
1548 | * Corner case handling. This is called from add_to_page_cache() | |
1549 | * in usual. But some FS (shmem) precharges this page before calling it | |
1550 | * and call add_to_page_cache() with GFP_NOWAIT. | |
1551 | * | |
1552 | * For GFP_NOWAIT case, the page may be pre-charged before calling | |
1553 | * add_to_page_cache(). (See shmem.c) check it here and avoid to call | |
1554 | * charge twice. (It works but has to pay a bit larger cost.) | |
b5a84319 KH |
1555 | * And when the page is SwapCache, it should take swap information |
1556 | * into account. This is under lock_page() now. | |
accf163e KH |
1557 | */ |
1558 | if (!(gfp_mask & __GFP_WAIT)) { | |
1559 | struct page_cgroup *pc; | |
1560 | ||
52d4b9ac KH |
1561 | |
1562 | pc = lookup_page_cgroup(page); | |
1563 | if (!pc) | |
1564 | return 0; | |
1565 | lock_page_cgroup(pc); | |
1566 | if (PageCgroupUsed(pc)) { | |
1567 | unlock_page_cgroup(pc); | |
accf163e KH |
1568 | return 0; |
1569 | } | |
52d4b9ac | 1570 | unlock_page_cgroup(pc); |
accf163e KH |
1571 | } |
1572 | ||
b5a84319 | 1573 | if (unlikely(!mm && !mem)) |
8697d331 | 1574 | mm = &init_mm; |
accf163e | 1575 | |
c05555b5 KH |
1576 | if (page_is_file_cache(page)) |
1577 | return mem_cgroup_charge_common(page, mm, gfp_mask, | |
e8589cc1 | 1578 | MEM_CGROUP_CHARGE_TYPE_CACHE, NULL); |
b5a84319 | 1579 | |
83aae4c7 DN |
1580 | /* shmem */ |
1581 | if (PageSwapCache(page)) { | |
1582 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); | |
1583 | if (!ret) | |
1584 | __mem_cgroup_commit_charge_swapin(page, mem, | |
1585 | MEM_CGROUP_CHARGE_TYPE_SHMEM); | |
1586 | } else | |
1587 | ret = mem_cgroup_charge_common(page, mm, gfp_mask, | |
1588 | MEM_CGROUP_CHARGE_TYPE_SHMEM, mem); | |
b5a84319 | 1589 | |
b5a84319 | 1590 | return ret; |
e8589cc1 KH |
1591 | } |
1592 | ||
54595fe2 KH |
1593 | /* |
1594 | * While swap-in, try_charge -> commit or cancel, the page is locked. | |
1595 | * And when try_charge() successfully returns, one refcnt to memcg without | |
1596 | * struct page_cgroup is aquired. This refcnt will be cumsumed by | |
1597 | * "commit()" or removed by "cancel()" | |
1598 | */ | |
8c7c6e34 KH |
1599 | int mem_cgroup_try_charge_swapin(struct mm_struct *mm, |
1600 | struct page *page, | |
1601 | gfp_t mask, struct mem_cgroup **ptr) | |
1602 | { | |
1603 | struct mem_cgroup *mem; | |
54595fe2 | 1604 | int ret; |
8c7c6e34 | 1605 | |
f8d66542 | 1606 | if (mem_cgroup_disabled()) |
8c7c6e34 KH |
1607 | return 0; |
1608 | ||
1609 | if (!do_swap_account) | |
1610 | goto charge_cur_mm; | |
8c7c6e34 KH |
1611 | /* |
1612 | * A racing thread's fault, or swapoff, may have already updated | |
1613 | * the pte, and even removed page from swap cache: return success | |
1614 | * to go on to do_swap_page()'s pte_same() test, which should fail. | |
1615 | */ | |
1616 | if (!PageSwapCache(page)) | |
1617 | return 0; | |
b5a84319 | 1618 | mem = try_get_mem_cgroup_from_swapcache(page); |
54595fe2 KH |
1619 | if (!mem) |
1620 | goto charge_cur_mm; | |
8c7c6e34 | 1621 | *ptr = mem; |
f64c3f54 | 1622 | ret = __mem_cgroup_try_charge(NULL, mask, ptr, true, page); |
54595fe2 KH |
1623 | /* drop extra refcnt from tryget */ |
1624 | css_put(&mem->css); | |
1625 | return ret; | |
8c7c6e34 KH |
1626 | charge_cur_mm: |
1627 | if (unlikely(!mm)) | |
1628 | mm = &init_mm; | |
f64c3f54 | 1629 | return __mem_cgroup_try_charge(mm, mask, ptr, true, page); |
8c7c6e34 KH |
1630 | } |
1631 | ||
83aae4c7 DN |
1632 | static void |
1633 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
1634 | enum charge_type ctype) | |
7a81b88c KH |
1635 | { |
1636 | struct page_cgroup *pc; | |
1637 | ||
f8d66542 | 1638 | if (mem_cgroup_disabled()) |
7a81b88c KH |
1639 | return; |
1640 | if (!ptr) | |
1641 | return; | |
88703267 | 1642 | cgroup_exclude_rmdir(&ptr->css); |
7a81b88c | 1643 | pc = lookup_page_cgroup(page); |
544122e5 | 1644 | mem_cgroup_lru_del_before_commit_swapcache(page); |
83aae4c7 | 1645 | __mem_cgroup_commit_charge(ptr, pc, ctype); |
544122e5 | 1646 | mem_cgroup_lru_add_after_commit_swapcache(page); |
8c7c6e34 KH |
1647 | /* |
1648 | * Now swap is on-memory. This means this page may be | |
1649 | * counted both as mem and swap....double count. | |
03f3c433 KH |
1650 | * Fix it by uncharging from memsw. Basically, this SwapCache is stable |
1651 | * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page() | |
1652 | * may call delete_from_swap_cache() before reach here. | |
8c7c6e34 | 1653 | */ |
03f3c433 | 1654 | if (do_swap_account && PageSwapCache(page)) { |
8c7c6e34 | 1655 | swp_entry_t ent = {.val = page_private(page)}; |
a3b2d692 | 1656 | unsigned short id; |
8c7c6e34 | 1657 | struct mem_cgroup *memcg; |
a3b2d692 KH |
1658 | |
1659 | id = swap_cgroup_record(ent, 0); | |
1660 | rcu_read_lock(); | |
1661 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 1662 | if (memcg) { |
a3b2d692 KH |
1663 | /* |
1664 | * This recorded memcg can be obsolete one. So, avoid | |
1665 | * calling css_tryget | |
1666 | */ | |
f64c3f54 | 1667 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE, NULL); |
8c7c6e34 KH |
1668 | mem_cgroup_put(memcg); |
1669 | } | |
a3b2d692 | 1670 | rcu_read_unlock(); |
8c7c6e34 | 1671 | } |
88703267 KH |
1672 | /* |
1673 | * At swapin, we may charge account against cgroup which has no tasks. | |
1674 | * So, rmdir()->pre_destroy() can be called while we do this charge. | |
1675 | * In that case, we need to call pre_destroy() again. check it here. | |
1676 | */ | |
1677 | cgroup_release_and_wakeup_rmdir(&ptr->css); | |
7a81b88c KH |
1678 | } |
1679 | ||
83aae4c7 DN |
1680 | void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) |
1681 | { | |
1682 | __mem_cgroup_commit_charge_swapin(page, ptr, | |
1683 | MEM_CGROUP_CHARGE_TYPE_MAPPED); | |
1684 | } | |
1685 | ||
7a81b88c KH |
1686 | void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem) |
1687 | { | |
f8d66542 | 1688 | if (mem_cgroup_disabled()) |
7a81b88c KH |
1689 | return; |
1690 | if (!mem) | |
1691 | return; | |
f64c3f54 | 1692 | res_counter_uncharge(&mem->res, PAGE_SIZE, NULL); |
8c7c6e34 | 1693 | if (do_swap_account) |
f64c3f54 | 1694 | res_counter_uncharge(&mem->memsw, PAGE_SIZE, NULL); |
7a81b88c KH |
1695 | css_put(&mem->css); |
1696 | } | |
1697 | ||
1698 | ||
8a9f3ccd | 1699 | /* |
69029cd5 | 1700 | * uncharge if !page_mapped(page) |
8a9f3ccd | 1701 | */ |
8c7c6e34 | 1702 | static struct mem_cgroup * |
69029cd5 | 1703 | __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) |
8a9f3ccd | 1704 | { |
8289546e | 1705 | struct page_cgroup *pc; |
8c7c6e34 | 1706 | struct mem_cgroup *mem = NULL; |
072c56c1 | 1707 | struct mem_cgroup_per_zone *mz; |
f64c3f54 | 1708 | bool soft_limit_excess = false; |
8a9f3ccd | 1709 | |
f8d66542 | 1710 | if (mem_cgroup_disabled()) |
8c7c6e34 | 1711 | return NULL; |
4077960e | 1712 | |
d13d1443 | 1713 | if (PageSwapCache(page)) |
8c7c6e34 | 1714 | return NULL; |
d13d1443 | 1715 | |
8697d331 | 1716 | /* |
3c541e14 | 1717 | * Check if our page_cgroup is valid |
8697d331 | 1718 | */ |
52d4b9ac KH |
1719 | pc = lookup_page_cgroup(page); |
1720 | if (unlikely(!pc || !PageCgroupUsed(pc))) | |
8c7c6e34 | 1721 | return NULL; |
b9c565d5 | 1722 | |
52d4b9ac | 1723 | lock_page_cgroup(pc); |
d13d1443 | 1724 | |
8c7c6e34 KH |
1725 | mem = pc->mem_cgroup; |
1726 | ||
d13d1443 KH |
1727 | if (!PageCgroupUsed(pc)) |
1728 | goto unlock_out; | |
1729 | ||
1730 | switch (ctype) { | |
1731 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
8a9478ca | 1732 | case MEM_CGROUP_CHARGE_TYPE_DROP: |
d13d1443 KH |
1733 | if (page_mapped(page)) |
1734 | goto unlock_out; | |
1735 | break; | |
1736 | case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: | |
1737 | if (!PageAnon(page)) { /* Shared memory */ | |
1738 | if (page->mapping && !page_is_file_cache(page)) | |
1739 | goto unlock_out; | |
1740 | } else if (page_mapped(page)) /* Anon */ | |
1741 | goto unlock_out; | |
1742 | break; | |
1743 | default: | |
1744 | break; | |
52d4b9ac | 1745 | } |
d13d1443 | 1746 | |
f64c3f54 | 1747 | res_counter_uncharge(&mem->res, PAGE_SIZE, &soft_limit_excess); |
8c7c6e34 | 1748 | if (do_swap_account && (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT)) |
f64c3f54 | 1749 | res_counter_uncharge(&mem->memsw, PAGE_SIZE, NULL); |
08e552c6 | 1750 | mem_cgroup_charge_statistics(mem, pc, false); |
04046e1a | 1751 | |
52d4b9ac | 1752 | ClearPageCgroupUsed(pc); |
544122e5 KH |
1753 | /* |
1754 | * pc->mem_cgroup is not cleared here. It will be accessed when it's | |
1755 | * freed from LRU. This is safe because uncharged page is expected not | |
1756 | * to be reused (freed soon). Exception is SwapCache, it's handled by | |
1757 | * special functions. | |
1758 | */ | |
b9c565d5 | 1759 | |
69029cd5 | 1760 | mz = page_cgroup_zoneinfo(pc); |
52d4b9ac | 1761 | unlock_page_cgroup(pc); |
fb59e9f1 | 1762 | |
f64c3f54 BS |
1763 | if (soft_limit_excess && mem_cgroup_soft_limit_check(mem)) |
1764 | mem_cgroup_update_tree(mem, page); | |
a7fe942e KH |
1765 | /* at swapout, this memcg will be accessed to record to swap */ |
1766 | if (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT) | |
1767 | css_put(&mem->css); | |
6d12e2d8 | 1768 | |
8c7c6e34 | 1769 | return mem; |
d13d1443 KH |
1770 | |
1771 | unlock_out: | |
1772 | unlock_page_cgroup(pc); | |
8c7c6e34 | 1773 | return NULL; |
3c541e14 BS |
1774 | } |
1775 | ||
69029cd5 KH |
1776 | void mem_cgroup_uncharge_page(struct page *page) |
1777 | { | |
52d4b9ac KH |
1778 | /* early check. */ |
1779 | if (page_mapped(page)) | |
1780 | return; | |
1781 | if (page->mapping && !PageAnon(page)) | |
1782 | return; | |
69029cd5 KH |
1783 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED); |
1784 | } | |
1785 | ||
1786 | void mem_cgroup_uncharge_cache_page(struct page *page) | |
1787 | { | |
1788 | VM_BUG_ON(page_mapped(page)); | |
b7abea96 | 1789 | VM_BUG_ON(page->mapping); |
69029cd5 KH |
1790 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); |
1791 | } | |
1792 | ||
e767e056 | 1793 | #ifdef CONFIG_SWAP |
8c7c6e34 | 1794 | /* |
e767e056 | 1795 | * called after __delete_from_swap_cache() and drop "page" account. |
8c7c6e34 KH |
1796 | * memcg information is recorded to swap_cgroup of "ent" |
1797 | */ | |
8a9478ca KH |
1798 | void |
1799 | mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout) | |
8c7c6e34 KH |
1800 | { |
1801 | struct mem_cgroup *memcg; | |
8a9478ca KH |
1802 | int ctype = MEM_CGROUP_CHARGE_TYPE_SWAPOUT; |
1803 | ||
1804 | if (!swapout) /* this was a swap cache but the swap is unused ! */ | |
1805 | ctype = MEM_CGROUP_CHARGE_TYPE_DROP; | |
1806 | ||
1807 | memcg = __mem_cgroup_uncharge_common(page, ctype); | |
8c7c6e34 | 1808 | |
8c7c6e34 | 1809 | /* record memcg information */ |
8a9478ca | 1810 | if (do_swap_account && swapout && memcg) { |
a3b2d692 | 1811 | swap_cgroup_record(ent, css_id(&memcg->css)); |
8c7c6e34 KH |
1812 | mem_cgroup_get(memcg); |
1813 | } | |
8a9478ca | 1814 | if (swapout && memcg) |
a7fe942e | 1815 | css_put(&memcg->css); |
8c7c6e34 | 1816 | } |
e767e056 | 1817 | #endif |
8c7c6e34 KH |
1818 | |
1819 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
1820 | /* | |
1821 | * called from swap_entry_free(). remove record in swap_cgroup and | |
1822 | * uncharge "memsw" account. | |
1823 | */ | |
1824 | void mem_cgroup_uncharge_swap(swp_entry_t ent) | |
d13d1443 | 1825 | { |
8c7c6e34 | 1826 | struct mem_cgroup *memcg; |
a3b2d692 | 1827 | unsigned short id; |
8c7c6e34 KH |
1828 | |
1829 | if (!do_swap_account) | |
1830 | return; | |
1831 | ||
a3b2d692 KH |
1832 | id = swap_cgroup_record(ent, 0); |
1833 | rcu_read_lock(); | |
1834 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 1835 | if (memcg) { |
a3b2d692 KH |
1836 | /* |
1837 | * We uncharge this because swap is freed. | |
1838 | * This memcg can be obsolete one. We avoid calling css_tryget | |
1839 | */ | |
f64c3f54 | 1840 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE, NULL); |
8c7c6e34 KH |
1841 | mem_cgroup_put(memcg); |
1842 | } | |
a3b2d692 | 1843 | rcu_read_unlock(); |
d13d1443 | 1844 | } |
8c7c6e34 | 1845 | #endif |
d13d1443 | 1846 | |
ae41be37 | 1847 | /* |
01b1ae63 KH |
1848 | * Before starting migration, account PAGE_SIZE to mem_cgroup that the old |
1849 | * page belongs to. | |
ae41be37 | 1850 | */ |
01b1ae63 | 1851 | int mem_cgroup_prepare_migration(struct page *page, struct mem_cgroup **ptr) |
ae41be37 KH |
1852 | { |
1853 | struct page_cgroup *pc; | |
e8589cc1 | 1854 | struct mem_cgroup *mem = NULL; |
e8589cc1 | 1855 | int ret = 0; |
8869b8f6 | 1856 | |
f8d66542 | 1857 | if (mem_cgroup_disabled()) |
4077960e BS |
1858 | return 0; |
1859 | ||
52d4b9ac KH |
1860 | pc = lookup_page_cgroup(page); |
1861 | lock_page_cgroup(pc); | |
1862 | if (PageCgroupUsed(pc)) { | |
e8589cc1 KH |
1863 | mem = pc->mem_cgroup; |
1864 | css_get(&mem->css); | |
e8589cc1 | 1865 | } |
52d4b9ac | 1866 | unlock_page_cgroup(pc); |
01b1ae63 | 1867 | |
e8589cc1 | 1868 | if (mem) { |
f64c3f54 BS |
1869 | ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false, |
1870 | page); | |
e8589cc1 KH |
1871 | css_put(&mem->css); |
1872 | } | |
01b1ae63 | 1873 | *ptr = mem; |
e8589cc1 | 1874 | return ret; |
ae41be37 | 1875 | } |
8869b8f6 | 1876 | |
69029cd5 | 1877 | /* remove redundant charge if migration failed*/ |
01b1ae63 KH |
1878 | void mem_cgroup_end_migration(struct mem_cgroup *mem, |
1879 | struct page *oldpage, struct page *newpage) | |
ae41be37 | 1880 | { |
01b1ae63 KH |
1881 | struct page *target, *unused; |
1882 | struct page_cgroup *pc; | |
1883 | enum charge_type ctype; | |
1884 | ||
1885 | if (!mem) | |
1886 | return; | |
88703267 | 1887 | cgroup_exclude_rmdir(&mem->css); |
01b1ae63 KH |
1888 | /* at migration success, oldpage->mapping is NULL. */ |
1889 | if (oldpage->mapping) { | |
1890 | target = oldpage; | |
1891 | unused = NULL; | |
1892 | } else { | |
1893 | target = newpage; | |
1894 | unused = oldpage; | |
1895 | } | |
1896 | ||
1897 | if (PageAnon(target)) | |
1898 | ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED; | |
1899 | else if (page_is_file_cache(target)) | |
1900 | ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; | |
1901 | else | |
1902 | ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; | |
1903 | ||
1904 | /* unused page is not on radix-tree now. */ | |
d13d1443 | 1905 | if (unused) |
01b1ae63 KH |
1906 | __mem_cgroup_uncharge_common(unused, ctype); |
1907 | ||
1908 | pc = lookup_page_cgroup(target); | |
69029cd5 | 1909 | /* |
01b1ae63 KH |
1910 | * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup. |
1911 | * So, double-counting is effectively avoided. | |
1912 | */ | |
1913 | __mem_cgroup_commit_charge(mem, pc, ctype); | |
1914 | ||
1915 | /* | |
1916 | * Both of oldpage and newpage are still under lock_page(). | |
1917 | * Then, we don't have to care about race in radix-tree. | |
1918 | * But we have to be careful that this page is unmapped or not. | |
1919 | * | |
1920 | * There is a case for !page_mapped(). At the start of | |
1921 | * migration, oldpage was mapped. But now, it's zapped. | |
1922 | * But we know *target* page is not freed/reused under us. | |
1923 | * mem_cgroup_uncharge_page() does all necessary checks. | |
69029cd5 | 1924 | */ |
01b1ae63 KH |
1925 | if (ctype == MEM_CGROUP_CHARGE_TYPE_MAPPED) |
1926 | mem_cgroup_uncharge_page(target); | |
88703267 KH |
1927 | /* |
1928 | * At migration, we may charge account against cgroup which has no tasks | |
1929 | * So, rmdir()->pre_destroy() can be called while we do this charge. | |
1930 | * In that case, we need to call pre_destroy() again. check it here. | |
1931 | */ | |
1932 | cgroup_release_and_wakeup_rmdir(&mem->css); | |
ae41be37 | 1933 | } |
78fb7466 | 1934 | |
c9b0ed51 | 1935 | /* |
ae3abae6 DN |
1936 | * A call to try to shrink memory usage on charge failure at shmem's swapin. |
1937 | * Calling hierarchical_reclaim is not enough because we should update | |
1938 | * last_oom_jiffies to prevent pagefault_out_of_memory from invoking global OOM. | |
1939 | * Moreover considering hierarchy, we should reclaim from the mem_over_limit, | |
1940 | * not from the memcg which this page would be charged to. | |
1941 | * try_charge_swapin does all of these works properly. | |
c9b0ed51 | 1942 | */ |
ae3abae6 | 1943 | int mem_cgroup_shmem_charge_fallback(struct page *page, |
b5a84319 KH |
1944 | struct mm_struct *mm, |
1945 | gfp_t gfp_mask) | |
c9b0ed51 | 1946 | { |
b5a84319 | 1947 | struct mem_cgroup *mem = NULL; |
ae3abae6 | 1948 | int ret; |
c9b0ed51 | 1949 | |
f8d66542 | 1950 | if (mem_cgroup_disabled()) |
cede86ac | 1951 | return 0; |
c9b0ed51 | 1952 | |
ae3abae6 DN |
1953 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); |
1954 | if (!ret) | |
1955 | mem_cgroup_cancel_charge_swapin(mem); /* it does !mem check */ | |
c9b0ed51 | 1956 | |
ae3abae6 | 1957 | return ret; |
c9b0ed51 KH |
1958 | } |
1959 | ||
8c7c6e34 KH |
1960 | static DEFINE_MUTEX(set_limit_mutex); |
1961 | ||
d38d2a75 | 1962 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
8c7c6e34 | 1963 | unsigned long long val) |
628f4235 | 1964 | { |
81d39c20 | 1965 | int retry_count; |
628f4235 | 1966 | int progress; |
8c7c6e34 | 1967 | u64 memswlimit; |
628f4235 | 1968 | int ret = 0; |
81d39c20 KH |
1969 | int children = mem_cgroup_count_children(memcg); |
1970 | u64 curusage, oldusage; | |
1971 | ||
1972 | /* | |
1973 | * For keeping hierarchical_reclaim simple, how long we should retry | |
1974 | * is depends on callers. We set our retry-count to be function | |
1975 | * of # of children which we should visit in this loop. | |
1976 | */ | |
1977 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; | |
1978 | ||
1979 | oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); | |
628f4235 | 1980 | |
8c7c6e34 | 1981 | while (retry_count) { |
628f4235 KH |
1982 | if (signal_pending(current)) { |
1983 | ret = -EINTR; | |
1984 | break; | |
1985 | } | |
8c7c6e34 KH |
1986 | /* |
1987 | * Rather than hide all in some function, I do this in | |
1988 | * open coded manner. You see what this really does. | |
1989 | * We have to guarantee mem->res.limit < mem->memsw.limit. | |
1990 | */ | |
1991 | mutex_lock(&set_limit_mutex); | |
1992 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
1993 | if (memswlimit < val) { | |
1994 | ret = -EINVAL; | |
1995 | mutex_unlock(&set_limit_mutex); | |
628f4235 KH |
1996 | break; |
1997 | } | |
8c7c6e34 | 1998 | ret = res_counter_set_limit(&memcg->res, val); |
22a668d7 KH |
1999 | if (!ret) { |
2000 | if (memswlimit == val) | |
2001 | memcg->memsw_is_minimum = true; | |
2002 | else | |
2003 | memcg->memsw_is_minimum = false; | |
2004 | } | |
8c7c6e34 KH |
2005 | mutex_unlock(&set_limit_mutex); |
2006 | ||
2007 | if (!ret) | |
2008 | break; | |
2009 | ||
42e9abb6 | 2010 | progress = mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL, |
81d39c20 KH |
2011 | false, true); |
2012 | curusage = res_counter_read_u64(&memcg->res, RES_USAGE); | |
2013 | /* Usage is reduced ? */ | |
2014 | if (curusage >= oldusage) | |
2015 | retry_count--; | |
2016 | else | |
2017 | oldusage = curusage; | |
8c7c6e34 | 2018 | } |
14797e23 | 2019 | |
8c7c6e34 KH |
2020 | return ret; |
2021 | } | |
2022 | ||
338c8431 LZ |
2023 | static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, |
2024 | unsigned long long val) | |
8c7c6e34 | 2025 | { |
81d39c20 | 2026 | int retry_count; |
8c7c6e34 | 2027 | u64 memlimit, oldusage, curusage; |
81d39c20 KH |
2028 | int children = mem_cgroup_count_children(memcg); |
2029 | int ret = -EBUSY; | |
8c7c6e34 | 2030 | |
81d39c20 KH |
2031 | /* see mem_cgroup_resize_res_limit */ |
2032 | retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; | |
2033 | oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); | |
8c7c6e34 KH |
2034 | while (retry_count) { |
2035 | if (signal_pending(current)) { | |
2036 | ret = -EINTR; | |
2037 | break; | |
2038 | } | |
2039 | /* | |
2040 | * Rather than hide all in some function, I do this in | |
2041 | * open coded manner. You see what this really does. | |
2042 | * We have to guarantee mem->res.limit < mem->memsw.limit. | |
2043 | */ | |
2044 | mutex_lock(&set_limit_mutex); | |
2045 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
2046 | if (memlimit > val) { | |
2047 | ret = -EINVAL; | |
2048 | mutex_unlock(&set_limit_mutex); | |
2049 | break; | |
2050 | } | |
2051 | ret = res_counter_set_limit(&memcg->memsw, val); | |
22a668d7 KH |
2052 | if (!ret) { |
2053 | if (memlimit == val) | |
2054 | memcg->memsw_is_minimum = true; | |
2055 | else | |
2056 | memcg->memsw_is_minimum = false; | |
2057 | } | |
8c7c6e34 KH |
2058 | mutex_unlock(&set_limit_mutex); |
2059 | ||
2060 | if (!ret) | |
2061 | break; | |
2062 | ||
81d39c20 | 2063 | mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL, true, true); |
8c7c6e34 | 2064 | curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); |
81d39c20 | 2065 | /* Usage is reduced ? */ |
8c7c6e34 | 2066 | if (curusage >= oldusage) |
628f4235 | 2067 | retry_count--; |
81d39c20 KH |
2068 | else |
2069 | oldusage = curusage; | |
628f4235 KH |
2070 | } |
2071 | return ret; | |
2072 | } | |
2073 | ||
cc847582 KH |
2074 | /* |
2075 | * This routine traverse page_cgroup in given list and drop them all. | |
cc847582 KH |
2076 | * *And* this routine doesn't reclaim page itself, just removes page_cgroup. |
2077 | */ | |
f817ed48 | 2078 | static int mem_cgroup_force_empty_list(struct mem_cgroup *mem, |
08e552c6 | 2079 | int node, int zid, enum lru_list lru) |
cc847582 | 2080 | { |
08e552c6 KH |
2081 | struct zone *zone; |
2082 | struct mem_cgroup_per_zone *mz; | |
f817ed48 | 2083 | struct page_cgroup *pc, *busy; |
08e552c6 | 2084 | unsigned long flags, loop; |
072c56c1 | 2085 | struct list_head *list; |
f817ed48 | 2086 | int ret = 0; |
072c56c1 | 2087 | |
08e552c6 KH |
2088 | zone = &NODE_DATA(node)->node_zones[zid]; |
2089 | mz = mem_cgroup_zoneinfo(mem, node, zid); | |
b69408e8 | 2090 | list = &mz->lists[lru]; |
cc847582 | 2091 | |
f817ed48 KH |
2092 | loop = MEM_CGROUP_ZSTAT(mz, lru); |
2093 | /* give some margin against EBUSY etc...*/ | |
2094 | loop += 256; | |
2095 | busy = NULL; | |
2096 | while (loop--) { | |
2097 | ret = 0; | |
08e552c6 | 2098 | spin_lock_irqsave(&zone->lru_lock, flags); |
f817ed48 | 2099 | if (list_empty(list)) { |
08e552c6 | 2100 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
52d4b9ac | 2101 | break; |
f817ed48 KH |
2102 | } |
2103 | pc = list_entry(list->prev, struct page_cgroup, lru); | |
2104 | if (busy == pc) { | |
2105 | list_move(&pc->lru, list); | |
2106 | busy = 0; | |
08e552c6 | 2107 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 KH |
2108 | continue; |
2109 | } | |
08e552c6 | 2110 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 | 2111 | |
2c26fdd7 | 2112 | ret = mem_cgroup_move_parent(pc, mem, GFP_KERNEL); |
f817ed48 | 2113 | if (ret == -ENOMEM) |
52d4b9ac | 2114 | break; |
f817ed48 KH |
2115 | |
2116 | if (ret == -EBUSY || ret == -EINVAL) { | |
2117 | /* found lock contention or "pc" is obsolete. */ | |
2118 | busy = pc; | |
2119 | cond_resched(); | |
2120 | } else | |
2121 | busy = NULL; | |
cc847582 | 2122 | } |
08e552c6 | 2123 | |
f817ed48 KH |
2124 | if (!ret && !list_empty(list)) |
2125 | return -EBUSY; | |
2126 | return ret; | |
cc847582 KH |
2127 | } |
2128 | ||
2129 | /* | |
2130 | * make mem_cgroup's charge to be 0 if there is no task. | |
2131 | * This enables deleting this mem_cgroup. | |
2132 | */ | |
c1e862c1 | 2133 | static int mem_cgroup_force_empty(struct mem_cgroup *mem, bool free_all) |
cc847582 | 2134 | { |
f817ed48 KH |
2135 | int ret; |
2136 | int node, zid, shrink; | |
2137 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
c1e862c1 | 2138 | struct cgroup *cgrp = mem->css.cgroup; |
8869b8f6 | 2139 | |
cc847582 | 2140 | css_get(&mem->css); |
f817ed48 KH |
2141 | |
2142 | shrink = 0; | |
c1e862c1 KH |
2143 | /* should free all ? */ |
2144 | if (free_all) | |
2145 | goto try_to_free; | |
f817ed48 | 2146 | move_account: |
1ecaab2b | 2147 | while (mem->res.usage > 0) { |
f817ed48 | 2148 | ret = -EBUSY; |
c1e862c1 KH |
2149 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children)) |
2150 | goto out; | |
2151 | ret = -EINTR; | |
2152 | if (signal_pending(current)) | |
cc847582 | 2153 | goto out; |
52d4b9ac KH |
2154 | /* This is for making all *used* pages to be on LRU. */ |
2155 | lru_add_drain_all(); | |
f817ed48 | 2156 | ret = 0; |
299b4eaa | 2157 | for_each_node_state(node, N_HIGH_MEMORY) { |
f817ed48 | 2158 | for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { |
b69408e8 | 2159 | enum lru_list l; |
f817ed48 KH |
2160 | for_each_lru(l) { |
2161 | ret = mem_cgroup_force_empty_list(mem, | |
08e552c6 | 2162 | node, zid, l); |
f817ed48 KH |
2163 | if (ret) |
2164 | break; | |
2165 | } | |
1ecaab2b | 2166 | } |
f817ed48 KH |
2167 | if (ret) |
2168 | break; | |
2169 | } | |
2170 | /* it seems parent cgroup doesn't have enough mem */ | |
2171 | if (ret == -ENOMEM) | |
2172 | goto try_to_free; | |
52d4b9ac | 2173 | cond_resched(); |
cc847582 KH |
2174 | } |
2175 | ret = 0; | |
2176 | out: | |
2177 | css_put(&mem->css); | |
2178 | return ret; | |
f817ed48 KH |
2179 | |
2180 | try_to_free: | |
c1e862c1 KH |
2181 | /* returns EBUSY if there is a task or if we come here twice. */ |
2182 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) { | |
f817ed48 KH |
2183 | ret = -EBUSY; |
2184 | goto out; | |
2185 | } | |
c1e862c1 KH |
2186 | /* we call try-to-free pages for make this cgroup empty */ |
2187 | lru_add_drain_all(); | |
f817ed48 KH |
2188 | /* try to free all pages in this cgroup */ |
2189 | shrink = 1; | |
2190 | while (nr_retries && mem->res.usage > 0) { | |
2191 | int progress; | |
c1e862c1 KH |
2192 | |
2193 | if (signal_pending(current)) { | |
2194 | ret = -EINTR; | |
2195 | goto out; | |
2196 | } | |
a7885eb8 KM |
2197 | progress = try_to_free_mem_cgroup_pages(mem, GFP_KERNEL, |
2198 | false, get_swappiness(mem)); | |
c1e862c1 | 2199 | if (!progress) { |
f817ed48 | 2200 | nr_retries--; |
c1e862c1 | 2201 | /* maybe some writeback is necessary */ |
8aa7e847 | 2202 | congestion_wait(BLK_RW_ASYNC, HZ/10); |
c1e862c1 | 2203 | } |
f817ed48 KH |
2204 | |
2205 | } | |
08e552c6 | 2206 | lru_add_drain(); |
f817ed48 KH |
2207 | /* try move_account...there may be some *locked* pages. */ |
2208 | if (mem->res.usage) | |
2209 | goto move_account; | |
2210 | ret = 0; | |
2211 | goto out; | |
cc847582 KH |
2212 | } |
2213 | ||
c1e862c1 KH |
2214 | int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event) |
2215 | { | |
2216 | return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true); | |
2217 | } | |
2218 | ||
2219 | ||
18f59ea7 BS |
2220 | static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft) |
2221 | { | |
2222 | return mem_cgroup_from_cont(cont)->use_hierarchy; | |
2223 | } | |
2224 | ||
2225 | static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft, | |
2226 | u64 val) | |
2227 | { | |
2228 | int retval = 0; | |
2229 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); | |
2230 | struct cgroup *parent = cont->parent; | |
2231 | struct mem_cgroup *parent_mem = NULL; | |
2232 | ||
2233 | if (parent) | |
2234 | parent_mem = mem_cgroup_from_cont(parent); | |
2235 | ||
2236 | cgroup_lock(); | |
2237 | /* | |
2238 | * If parent's use_hiearchy is set, we can't make any modifications | |
2239 | * in the child subtrees. If it is unset, then the change can | |
2240 | * occur, provided the current cgroup has no children. | |
2241 | * | |
2242 | * For the root cgroup, parent_mem is NULL, we allow value to be | |
2243 | * set if there are no children. | |
2244 | */ | |
2245 | if ((!parent_mem || !parent_mem->use_hierarchy) && | |
2246 | (val == 1 || val == 0)) { | |
2247 | if (list_empty(&cont->children)) | |
2248 | mem->use_hierarchy = val; | |
2249 | else | |
2250 | retval = -EBUSY; | |
2251 | } else | |
2252 | retval = -EINVAL; | |
2253 | cgroup_unlock(); | |
2254 | ||
2255 | return retval; | |
2256 | } | |
2257 | ||
2c3daa72 | 2258 | static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) |
8cdea7c0 | 2259 | { |
8c7c6e34 KH |
2260 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
2261 | u64 val = 0; | |
2262 | int type, name; | |
2263 | ||
2264 | type = MEMFILE_TYPE(cft->private); | |
2265 | name = MEMFILE_ATTR(cft->private); | |
2266 | switch (type) { | |
2267 | case _MEM: | |
2268 | val = res_counter_read_u64(&mem->res, name); | |
2269 | break; | |
2270 | case _MEMSWAP: | |
338c8431 | 2271 | val = res_counter_read_u64(&mem->memsw, name); |
8c7c6e34 KH |
2272 | break; |
2273 | default: | |
2274 | BUG(); | |
2275 | break; | |
2276 | } | |
2277 | return val; | |
8cdea7c0 | 2278 | } |
628f4235 KH |
2279 | /* |
2280 | * The user of this function is... | |
2281 | * RES_LIMIT. | |
2282 | */ | |
856c13aa PM |
2283 | static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, |
2284 | const char *buffer) | |
8cdea7c0 | 2285 | { |
628f4235 | 2286 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
8c7c6e34 | 2287 | int type, name; |
628f4235 KH |
2288 | unsigned long long val; |
2289 | int ret; | |
2290 | ||
8c7c6e34 KH |
2291 | type = MEMFILE_TYPE(cft->private); |
2292 | name = MEMFILE_ATTR(cft->private); | |
2293 | switch (name) { | |
628f4235 | 2294 | case RES_LIMIT: |
4b3bde4c BS |
2295 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
2296 | ret = -EINVAL; | |
2297 | break; | |
2298 | } | |
628f4235 KH |
2299 | /* This function does all necessary parse...reuse it */ |
2300 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
8c7c6e34 KH |
2301 | if (ret) |
2302 | break; | |
2303 | if (type == _MEM) | |
628f4235 | 2304 | ret = mem_cgroup_resize_limit(memcg, val); |
8c7c6e34 KH |
2305 | else |
2306 | ret = mem_cgroup_resize_memsw_limit(memcg, val); | |
628f4235 | 2307 | break; |
296c81d8 BS |
2308 | case RES_SOFT_LIMIT: |
2309 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
2310 | if (ret) | |
2311 | break; | |
2312 | /* | |
2313 | * For memsw, soft limits are hard to implement in terms | |
2314 | * of semantics, for now, we support soft limits for | |
2315 | * control without swap | |
2316 | */ | |
2317 | if (type == _MEM) | |
2318 | ret = res_counter_set_soft_limit(&memcg->res, val); | |
2319 | else | |
2320 | ret = -EINVAL; | |
2321 | break; | |
628f4235 KH |
2322 | default: |
2323 | ret = -EINVAL; /* should be BUG() ? */ | |
2324 | break; | |
2325 | } | |
2326 | return ret; | |
8cdea7c0 BS |
2327 | } |
2328 | ||
fee7b548 KH |
2329 | static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, |
2330 | unsigned long long *mem_limit, unsigned long long *memsw_limit) | |
2331 | { | |
2332 | struct cgroup *cgroup; | |
2333 | unsigned long long min_limit, min_memsw_limit, tmp; | |
2334 | ||
2335 | min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
2336 | min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
2337 | cgroup = memcg->css.cgroup; | |
2338 | if (!memcg->use_hierarchy) | |
2339 | goto out; | |
2340 | ||
2341 | while (cgroup->parent) { | |
2342 | cgroup = cgroup->parent; | |
2343 | memcg = mem_cgroup_from_cont(cgroup); | |
2344 | if (!memcg->use_hierarchy) | |
2345 | break; | |
2346 | tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
2347 | min_limit = min(min_limit, tmp); | |
2348 | tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
2349 | min_memsw_limit = min(min_memsw_limit, tmp); | |
2350 | } | |
2351 | out: | |
2352 | *mem_limit = min_limit; | |
2353 | *memsw_limit = min_memsw_limit; | |
2354 | return; | |
2355 | } | |
2356 | ||
29f2a4da | 2357 | static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) |
c84872e1 PE |
2358 | { |
2359 | struct mem_cgroup *mem; | |
8c7c6e34 | 2360 | int type, name; |
c84872e1 PE |
2361 | |
2362 | mem = mem_cgroup_from_cont(cont); | |
8c7c6e34 KH |
2363 | type = MEMFILE_TYPE(event); |
2364 | name = MEMFILE_ATTR(event); | |
2365 | switch (name) { | |
29f2a4da | 2366 | case RES_MAX_USAGE: |
8c7c6e34 KH |
2367 | if (type == _MEM) |
2368 | res_counter_reset_max(&mem->res); | |
2369 | else | |
2370 | res_counter_reset_max(&mem->memsw); | |
29f2a4da PE |
2371 | break; |
2372 | case RES_FAILCNT: | |
8c7c6e34 KH |
2373 | if (type == _MEM) |
2374 | res_counter_reset_failcnt(&mem->res); | |
2375 | else | |
2376 | res_counter_reset_failcnt(&mem->memsw); | |
29f2a4da PE |
2377 | break; |
2378 | } | |
f64c3f54 | 2379 | |
85cc59db | 2380 | return 0; |
c84872e1 PE |
2381 | } |
2382 | ||
14067bb3 KH |
2383 | |
2384 | /* For read statistics */ | |
2385 | enum { | |
2386 | MCS_CACHE, | |
2387 | MCS_RSS, | |
d69b042f | 2388 | MCS_MAPPED_FILE, |
14067bb3 KH |
2389 | MCS_PGPGIN, |
2390 | MCS_PGPGOUT, | |
2391 | MCS_INACTIVE_ANON, | |
2392 | MCS_ACTIVE_ANON, | |
2393 | MCS_INACTIVE_FILE, | |
2394 | MCS_ACTIVE_FILE, | |
2395 | MCS_UNEVICTABLE, | |
2396 | NR_MCS_STAT, | |
2397 | }; | |
2398 | ||
2399 | struct mcs_total_stat { | |
2400 | s64 stat[NR_MCS_STAT]; | |
d2ceb9b7 KH |
2401 | }; |
2402 | ||
14067bb3 KH |
2403 | struct { |
2404 | char *local_name; | |
2405 | char *total_name; | |
2406 | } memcg_stat_strings[NR_MCS_STAT] = { | |
2407 | {"cache", "total_cache"}, | |
2408 | {"rss", "total_rss"}, | |
d69b042f | 2409 | {"mapped_file", "total_mapped_file"}, |
14067bb3 KH |
2410 | {"pgpgin", "total_pgpgin"}, |
2411 | {"pgpgout", "total_pgpgout"}, | |
2412 | {"inactive_anon", "total_inactive_anon"}, | |
2413 | {"active_anon", "total_active_anon"}, | |
2414 | {"inactive_file", "total_inactive_file"}, | |
2415 | {"active_file", "total_active_file"}, | |
2416 | {"unevictable", "total_unevictable"} | |
2417 | }; | |
2418 | ||
2419 | ||
2420 | static int mem_cgroup_get_local_stat(struct mem_cgroup *mem, void *data) | |
2421 | { | |
2422 | struct mcs_total_stat *s = data; | |
2423 | s64 val; | |
2424 | ||
2425 | /* per cpu stat */ | |
2426 | val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_CACHE); | |
2427 | s->stat[MCS_CACHE] += val * PAGE_SIZE; | |
2428 | val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_RSS); | |
2429 | s->stat[MCS_RSS] += val * PAGE_SIZE; | |
d69b042f BS |
2430 | val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_MAPPED_FILE); |
2431 | s->stat[MCS_MAPPED_FILE] += val * PAGE_SIZE; | |
14067bb3 KH |
2432 | val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_PGPGIN_COUNT); |
2433 | s->stat[MCS_PGPGIN] += val; | |
2434 | val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_PGPGOUT_COUNT); | |
2435 | s->stat[MCS_PGPGOUT] += val; | |
2436 | ||
2437 | /* per zone stat */ | |
2438 | val = mem_cgroup_get_local_zonestat(mem, LRU_INACTIVE_ANON); | |
2439 | s->stat[MCS_INACTIVE_ANON] += val * PAGE_SIZE; | |
2440 | val = mem_cgroup_get_local_zonestat(mem, LRU_ACTIVE_ANON); | |
2441 | s->stat[MCS_ACTIVE_ANON] += val * PAGE_SIZE; | |
2442 | val = mem_cgroup_get_local_zonestat(mem, LRU_INACTIVE_FILE); | |
2443 | s->stat[MCS_INACTIVE_FILE] += val * PAGE_SIZE; | |
2444 | val = mem_cgroup_get_local_zonestat(mem, LRU_ACTIVE_FILE); | |
2445 | s->stat[MCS_ACTIVE_FILE] += val * PAGE_SIZE; | |
2446 | val = mem_cgroup_get_local_zonestat(mem, LRU_UNEVICTABLE); | |
2447 | s->stat[MCS_UNEVICTABLE] += val * PAGE_SIZE; | |
2448 | return 0; | |
2449 | } | |
2450 | ||
2451 | static void | |
2452 | mem_cgroup_get_total_stat(struct mem_cgroup *mem, struct mcs_total_stat *s) | |
2453 | { | |
2454 | mem_cgroup_walk_tree(mem, s, mem_cgroup_get_local_stat); | |
2455 | } | |
2456 | ||
c64745cf PM |
2457 | static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, |
2458 | struct cgroup_map_cb *cb) | |
d2ceb9b7 | 2459 | { |
d2ceb9b7 | 2460 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); |
14067bb3 | 2461 | struct mcs_total_stat mystat; |
d2ceb9b7 KH |
2462 | int i; |
2463 | ||
14067bb3 KH |
2464 | memset(&mystat, 0, sizeof(mystat)); |
2465 | mem_cgroup_get_local_stat(mem_cont, &mystat); | |
d2ceb9b7 | 2466 | |
14067bb3 KH |
2467 | for (i = 0; i < NR_MCS_STAT; i++) |
2468 | cb->fill(cb, memcg_stat_strings[i].local_name, mystat.stat[i]); | |
7b854121 | 2469 | |
14067bb3 | 2470 | /* Hierarchical information */ |
fee7b548 KH |
2471 | { |
2472 | unsigned long long limit, memsw_limit; | |
2473 | memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit); | |
2474 | cb->fill(cb, "hierarchical_memory_limit", limit); | |
2475 | if (do_swap_account) | |
2476 | cb->fill(cb, "hierarchical_memsw_limit", memsw_limit); | |
2477 | } | |
7f016ee8 | 2478 | |
14067bb3 KH |
2479 | memset(&mystat, 0, sizeof(mystat)); |
2480 | mem_cgroup_get_total_stat(mem_cont, &mystat); | |
2481 | for (i = 0; i < NR_MCS_STAT; i++) | |
2482 | cb->fill(cb, memcg_stat_strings[i].total_name, mystat.stat[i]); | |
2483 | ||
2484 | ||
7f016ee8 | 2485 | #ifdef CONFIG_DEBUG_VM |
c772be93 | 2486 | cb->fill(cb, "inactive_ratio", calc_inactive_ratio(mem_cont, NULL)); |
7f016ee8 KM |
2487 | |
2488 | { | |
2489 | int nid, zid; | |
2490 | struct mem_cgroup_per_zone *mz; | |
2491 | unsigned long recent_rotated[2] = {0, 0}; | |
2492 | unsigned long recent_scanned[2] = {0, 0}; | |
2493 | ||
2494 | for_each_online_node(nid) | |
2495 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
2496 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); | |
2497 | ||
2498 | recent_rotated[0] += | |
2499 | mz->reclaim_stat.recent_rotated[0]; | |
2500 | recent_rotated[1] += | |
2501 | mz->reclaim_stat.recent_rotated[1]; | |
2502 | recent_scanned[0] += | |
2503 | mz->reclaim_stat.recent_scanned[0]; | |
2504 | recent_scanned[1] += | |
2505 | mz->reclaim_stat.recent_scanned[1]; | |
2506 | } | |
2507 | cb->fill(cb, "recent_rotated_anon", recent_rotated[0]); | |
2508 | cb->fill(cb, "recent_rotated_file", recent_rotated[1]); | |
2509 | cb->fill(cb, "recent_scanned_anon", recent_scanned[0]); | |
2510 | cb->fill(cb, "recent_scanned_file", recent_scanned[1]); | |
2511 | } | |
2512 | #endif | |
2513 | ||
d2ceb9b7 KH |
2514 | return 0; |
2515 | } | |
2516 | ||
a7885eb8 KM |
2517 | static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft) |
2518 | { | |
2519 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2520 | ||
2521 | return get_swappiness(memcg); | |
2522 | } | |
2523 | ||
2524 | static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, | |
2525 | u64 val) | |
2526 | { | |
2527 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2528 | struct mem_cgroup *parent; | |
068b38c1 | 2529 | |
a7885eb8 KM |
2530 | if (val > 100) |
2531 | return -EINVAL; | |
2532 | ||
2533 | if (cgrp->parent == NULL) | |
2534 | return -EINVAL; | |
2535 | ||
2536 | parent = mem_cgroup_from_cont(cgrp->parent); | |
068b38c1 LZ |
2537 | |
2538 | cgroup_lock(); | |
2539 | ||
a7885eb8 KM |
2540 | /* If under hierarchy, only empty-root can set this value */ |
2541 | if ((parent->use_hierarchy) || | |
068b38c1 LZ |
2542 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
2543 | cgroup_unlock(); | |
a7885eb8 | 2544 | return -EINVAL; |
068b38c1 | 2545 | } |
a7885eb8 KM |
2546 | |
2547 | spin_lock(&memcg->reclaim_param_lock); | |
2548 | memcg->swappiness = val; | |
2549 | spin_unlock(&memcg->reclaim_param_lock); | |
2550 | ||
068b38c1 LZ |
2551 | cgroup_unlock(); |
2552 | ||
a7885eb8 KM |
2553 | return 0; |
2554 | } | |
2555 | ||
c1e862c1 | 2556 | |
8cdea7c0 BS |
2557 | static struct cftype mem_cgroup_files[] = { |
2558 | { | |
0eea1030 | 2559 | .name = "usage_in_bytes", |
8c7c6e34 | 2560 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
2c3daa72 | 2561 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 2562 | }, |
c84872e1 PE |
2563 | { |
2564 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 2565 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
29f2a4da | 2566 | .trigger = mem_cgroup_reset, |
c84872e1 PE |
2567 | .read_u64 = mem_cgroup_read, |
2568 | }, | |
8cdea7c0 | 2569 | { |
0eea1030 | 2570 | .name = "limit_in_bytes", |
8c7c6e34 | 2571 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
856c13aa | 2572 | .write_string = mem_cgroup_write, |
2c3daa72 | 2573 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 2574 | }, |
296c81d8 BS |
2575 | { |
2576 | .name = "soft_limit_in_bytes", | |
2577 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
2578 | .write_string = mem_cgroup_write, | |
2579 | .read_u64 = mem_cgroup_read, | |
2580 | }, | |
8cdea7c0 BS |
2581 | { |
2582 | .name = "failcnt", | |
8c7c6e34 | 2583 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
29f2a4da | 2584 | .trigger = mem_cgroup_reset, |
2c3daa72 | 2585 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 2586 | }, |
d2ceb9b7 KH |
2587 | { |
2588 | .name = "stat", | |
c64745cf | 2589 | .read_map = mem_control_stat_show, |
d2ceb9b7 | 2590 | }, |
c1e862c1 KH |
2591 | { |
2592 | .name = "force_empty", | |
2593 | .trigger = mem_cgroup_force_empty_write, | |
2594 | }, | |
18f59ea7 BS |
2595 | { |
2596 | .name = "use_hierarchy", | |
2597 | .write_u64 = mem_cgroup_hierarchy_write, | |
2598 | .read_u64 = mem_cgroup_hierarchy_read, | |
2599 | }, | |
a7885eb8 KM |
2600 | { |
2601 | .name = "swappiness", | |
2602 | .read_u64 = mem_cgroup_swappiness_read, | |
2603 | .write_u64 = mem_cgroup_swappiness_write, | |
2604 | }, | |
8cdea7c0 BS |
2605 | }; |
2606 | ||
8c7c6e34 KH |
2607 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
2608 | static struct cftype memsw_cgroup_files[] = { | |
2609 | { | |
2610 | .name = "memsw.usage_in_bytes", | |
2611 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
2612 | .read_u64 = mem_cgroup_read, | |
2613 | }, | |
2614 | { | |
2615 | .name = "memsw.max_usage_in_bytes", | |
2616 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
2617 | .trigger = mem_cgroup_reset, | |
2618 | .read_u64 = mem_cgroup_read, | |
2619 | }, | |
2620 | { | |
2621 | .name = "memsw.limit_in_bytes", | |
2622 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
2623 | .write_string = mem_cgroup_write, | |
2624 | .read_u64 = mem_cgroup_read, | |
2625 | }, | |
2626 | { | |
2627 | .name = "memsw.failcnt", | |
2628 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
2629 | .trigger = mem_cgroup_reset, | |
2630 | .read_u64 = mem_cgroup_read, | |
2631 | }, | |
2632 | }; | |
2633 | ||
2634 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
2635 | { | |
2636 | if (!do_swap_account) | |
2637 | return 0; | |
2638 | return cgroup_add_files(cont, ss, memsw_cgroup_files, | |
2639 | ARRAY_SIZE(memsw_cgroup_files)); | |
2640 | }; | |
2641 | #else | |
2642 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
2643 | { | |
2644 | return 0; | |
2645 | } | |
2646 | #endif | |
2647 | ||
6d12e2d8 KH |
2648 | static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
2649 | { | |
2650 | struct mem_cgroup_per_node *pn; | |
1ecaab2b | 2651 | struct mem_cgroup_per_zone *mz; |
b69408e8 | 2652 | enum lru_list l; |
41e3355d | 2653 | int zone, tmp = node; |
1ecaab2b KH |
2654 | /* |
2655 | * This routine is called against possible nodes. | |
2656 | * But it's BUG to call kmalloc() against offline node. | |
2657 | * | |
2658 | * TODO: this routine can waste much memory for nodes which will | |
2659 | * never be onlined. It's better to use memory hotplug callback | |
2660 | * function. | |
2661 | */ | |
41e3355d KH |
2662 | if (!node_state(node, N_NORMAL_MEMORY)) |
2663 | tmp = -1; | |
2664 | pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, tmp); | |
6d12e2d8 KH |
2665 | if (!pn) |
2666 | return 1; | |
1ecaab2b | 2667 | |
6d12e2d8 KH |
2668 | mem->info.nodeinfo[node] = pn; |
2669 | memset(pn, 0, sizeof(*pn)); | |
1ecaab2b KH |
2670 | |
2671 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
2672 | mz = &pn->zoneinfo[zone]; | |
b69408e8 CL |
2673 | for_each_lru(l) |
2674 | INIT_LIST_HEAD(&mz->lists[l]); | |
f64c3f54 | 2675 | mz->usage_in_excess = 0; |
1ecaab2b | 2676 | } |
6d12e2d8 KH |
2677 | return 0; |
2678 | } | |
2679 | ||
1ecaab2b KH |
2680 | static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
2681 | { | |
2682 | kfree(mem->info.nodeinfo[node]); | |
2683 | } | |
2684 | ||
c8dad2bb JB |
2685 | static int mem_cgroup_size(void) |
2686 | { | |
2687 | int cpustat_size = nr_cpu_ids * sizeof(struct mem_cgroup_stat_cpu); | |
2688 | return sizeof(struct mem_cgroup) + cpustat_size; | |
2689 | } | |
2690 | ||
33327948 KH |
2691 | static struct mem_cgroup *mem_cgroup_alloc(void) |
2692 | { | |
2693 | struct mem_cgroup *mem; | |
c8dad2bb | 2694 | int size = mem_cgroup_size(); |
33327948 | 2695 | |
c8dad2bb JB |
2696 | if (size < PAGE_SIZE) |
2697 | mem = kmalloc(size, GFP_KERNEL); | |
33327948 | 2698 | else |
c8dad2bb | 2699 | mem = vmalloc(size); |
33327948 KH |
2700 | |
2701 | if (mem) | |
c8dad2bb | 2702 | memset(mem, 0, size); |
33327948 KH |
2703 | return mem; |
2704 | } | |
2705 | ||
8c7c6e34 KH |
2706 | /* |
2707 | * At destroying mem_cgroup, references from swap_cgroup can remain. | |
2708 | * (scanning all at force_empty is too costly...) | |
2709 | * | |
2710 | * Instead of clearing all references at force_empty, we remember | |
2711 | * the number of reference from swap_cgroup and free mem_cgroup when | |
2712 | * it goes down to 0. | |
2713 | * | |
8c7c6e34 KH |
2714 | * Removal of cgroup itself succeeds regardless of refs from swap. |
2715 | */ | |
2716 | ||
a7ba0eef | 2717 | static void __mem_cgroup_free(struct mem_cgroup *mem) |
33327948 | 2718 | { |
08e552c6 KH |
2719 | int node; |
2720 | ||
f64c3f54 | 2721 | mem_cgroup_remove_from_trees(mem); |
04046e1a KH |
2722 | free_css_id(&mem_cgroup_subsys, &mem->css); |
2723 | ||
08e552c6 KH |
2724 | for_each_node_state(node, N_POSSIBLE) |
2725 | free_mem_cgroup_per_zone_info(mem, node); | |
2726 | ||
c8dad2bb | 2727 | if (mem_cgroup_size() < PAGE_SIZE) |
33327948 KH |
2728 | kfree(mem); |
2729 | else | |
2730 | vfree(mem); | |
2731 | } | |
2732 | ||
8c7c6e34 KH |
2733 | static void mem_cgroup_get(struct mem_cgroup *mem) |
2734 | { | |
2735 | atomic_inc(&mem->refcnt); | |
2736 | } | |
2737 | ||
2738 | static void mem_cgroup_put(struct mem_cgroup *mem) | |
2739 | { | |
7bcc1bb1 DN |
2740 | if (atomic_dec_and_test(&mem->refcnt)) { |
2741 | struct mem_cgroup *parent = parent_mem_cgroup(mem); | |
a7ba0eef | 2742 | __mem_cgroup_free(mem); |
7bcc1bb1 DN |
2743 | if (parent) |
2744 | mem_cgroup_put(parent); | |
2745 | } | |
8c7c6e34 KH |
2746 | } |
2747 | ||
7bcc1bb1 DN |
2748 | /* |
2749 | * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. | |
2750 | */ | |
2751 | static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem) | |
2752 | { | |
2753 | if (!mem->res.parent) | |
2754 | return NULL; | |
2755 | return mem_cgroup_from_res_counter(mem->res.parent, res); | |
2756 | } | |
33327948 | 2757 | |
c077719b KH |
2758 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
2759 | static void __init enable_swap_cgroup(void) | |
2760 | { | |
f8d66542 | 2761 | if (!mem_cgroup_disabled() && really_do_swap_account) |
c077719b KH |
2762 | do_swap_account = 1; |
2763 | } | |
2764 | #else | |
2765 | static void __init enable_swap_cgroup(void) | |
2766 | { | |
2767 | } | |
2768 | #endif | |
2769 | ||
f64c3f54 BS |
2770 | static int mem_cgroup_soft_limit_tree_init(void) |
2771 | { | |
2772 | struct mem_cgroup_tree_per_node *rtpn; | |
2773 | struct mem_cgroup_tree_per_zone *rtpz; | |
2774 | int tmp, node, zone; | |
2775 | ||
2776 | for_each_node_state(node, N_POSSIBLE) { | |
2777 | tmp = node; | |
2778 | if (!node_state(node, N_NORMAL_MEMORY)) | |
2779 | tmp = -1; | |
2780 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, tmp); | |
2781 | if (!rtpn) | |
2782 | return 1; | |
2783 | ||
2784 | soft_limit_tree.rb_tree_per_node[node] = rtpn; | |
2785 | ||
2786 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
2787 | rtpz = &rtpn->rb_tree_per_zone[zone]; | |
2788 | rtpz->rb_root = RB_ROOT; | |
2789 | spin_lock_init(&rtpz->lock); | |
2790 | } | |
2791 | } | |
2792 | return 0; | |
2793 | } | |
2794 | ||
0eb253e2 | 2795 | static struct cgroup_subsys_state * __ref |
8cdea7c0 BS |
2796 | mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) |
2797 | { | |
28dbc4b6 | 2798 | struct mem_cgroup *mem, *parent; |
04046e1a | 2799 | long error = -ENOMEM; |
6d12e2d8 | 2800 | int node; |
8cdea7c0 | 2801 | |
c8dad2bb JB |
2802 | mem = mem_cgroup_alloc(); |
2803 | if (!mem) | |
04046e1a | 2804 | return ERR_PTR(error); |
78fb7466 | 2805 | |
6d12e2d8 KH |
2806 | for_each_node_state(node, N_POSSIBLE) |
2807 | if (alloc_mem_cgroup_per_zone_info(mem, node)) | |
2808 | goto free_out; | |
f64c3f54 | 2809 | |
c077719b | 2810 | /* root ? */ |
28dbc4b6 | 2811 | if (cont->parent == NULL) { |
c077719b | 2812 | enable_swap_cgroup(); |
28dbc4b6 | 2813 | parent = NULL; |
4b3bde4c | 2814 | root_mem_cgroup = mem; |
f64c3f54 BS |
2815 | if (mem_cgroup_soft_limit_tree_init()) |
2816 | goto free_out; | |
2817 | ||
18f59ea7 | 2818 | } else { |
28dbc4b6 | 2819 | parent = mem_cgroup_from_cont(cont->parent); |
18f59ea7 BS |
2820 | mem->use_hierarchy = parent->use_hierarchy; |
2821 | } | |
28dbc4b6 | 2822 | |
18f59ea7 BS |
2823 | if (parent && parent->use_hierarchy) { |
2824 | res_counter_init(&mem->res, &parent->res); | |
2825 | res_counter_init(&mem->memsw, &parent->memsw); | |
7bcc1bb1 DN |
2826 | /* |
2827 | * We increment refcnt of the parent to ensure that we can | |
2828 | * safely access it on res_counter_charge/uncharge. | |
2829 | * This refcnt will be decremented when freeing this | |
2830 | * mem_cgroup(see mem_cgroup_put). | |
2831 | */ | |
2832 | mem_cgroup_get(parent); | |
18f59ea7 BS |
2833 | } else { |
2834 | res_counter_init(&mem->res, NULL); | |
2835 | res_counter_init(&mem->memsw, NULL); | |
2836 | } | |
04046e1a | 2837 | mem->last_scanned_child = 0; |
2733c06a | 2838 | spin_lock_init(&mem->reclaim_param_lock); |
6d61ef40 | 2839 | |
a7885eb8 KM |
2840 | if (parent) |
2841 | mem->swappiness = get_swappiness(parent); | |
a7ba0eef | 2842 | atomic_set(&mem->refcnt, 1); |
8cdea7c0 | 2843 | return &mem->css; |
6d12e2d8 | 2844 | free_out: |
a7ba0eef | 2845 | __mem_cgroup_free(mem); |
4b3bde4c | 2846 | root_mem_cgroup = NULL; |
04046e1a | 2847 | return ERR_PTR(error); |
8cdea7c0 BS |
2848 | } |
2849 | ||
ec64f515 | 2850 | static int mem_cgroup_pre_destroy(struct cgroup_subsys *ss, |
df878fb0 KH |
2851 | struct cgroup *cont) |
2852 | { | |
2853 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); | |
ec64f515 KH |
2854 | |
2855 | return mem_cgroup_force_empty(mem, false); | |
df878fb0 KH |
2856 | } |
2857 | ||
8cdea7c0 BS |
2858 | static void mem_cgroup_destroy(struct cgroup_subsys *ss, |
2859 | struct cgroup *cont) | |
2860 | { | |
c268e994 | 2861 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
c268e994 | 2862 | |
c268e994 | 2863 | mem_cgroup_put(mem); |
8cdea7c0 BS |
2864 | } |
2865 | ||
2866 | static int mem_cgroup_populate(struct cgroup_subsys *ss, | |
2867 | struct cgroup *cont) | |
2868 | { | |
8c7c6e34 KH |
2869 | int ret; |
2870 | ||
2871 | ret = cgroup_add_files(cont, ss, mem_cgroup_files, | |
2872 | ARRAY_SIZE(mem_cgroup_files)); | |
2873 | ||
2874 | if (!ret) | |
2875 | ret = register_memsw_files(cont, ss); | |
2876 | return ret; | |
8cdea7c0 BS |
2877 | } |
2878 | ||
67e465a7 BS |
2879 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, |
2880 | struct cgroup *cont, | |
2881 | struct cgroup *old_cont, | |
be367d09 BB |
2882 | struct task_struct *p, |
2883 | bool threadgroup) | |
67e465a7 | 2884 | { |
7f4d454d | 2885 | mutex_lock(&memcg_tasklist); |
67e465a7 | 2886 | /* |
f9717d28 NK |
2887 | * FIXME: It's better to move charges of this process from old |
2888 | * memcg to new memcg. But it's just on TODO-List now. | |
67e465a7 | 2889 | */ |
7f4d454d | 2890 | mutex_unlock(&memcg_tasklist); |
67e465a7 BS |
2891 | } |
2892 | ||
8cdea7c0 BS |
2893 | struct cgroup_subsys mem_cgroup_subsys = { |
2894 | .name = "memory", | |
2895 | .subsys_id = mem_cgroup_subsys_id, | |
2896 | .create = mem_cgroup_create, | |
df878fb0 | 2897 | .pre_destroy = mem_cgroup_pre_destroy, |
8cdea7c0 BS |
2898 | .destroy = mem_cgroup_destroy, |
2899 | .populate = mem_cgroup_populate, | |
67e465a7 | 2900 | .attach = mem_cgroup_move_task, |
6d12e2d8 | 2901 | .early_init = 0, |
04046e1a | 2902 | .use_id = 1, |
8cdea7c0 | 2903 | }; |
c077719b KH |
2904 | |
2905 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
2906 | ||
2907 | static int __init disable_swap_account(char *s) | |
2908 | { | |
2909 | really_do_swap_account = 0; | |
2910 | return 1; | |
2911 | } | |
2912 | __setup("noswapaccount", disable_swap_account); | |
2913 | #endif |