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8cdea7c0 BS |
1 | /* memcontrol.c - Memory Controller |
2 | * | |
3 | * Copyright IBM Corporation, 2007 | |
4 | * Author Balbir Singh <balbir@linux.vnet.ibm.com> | |
5 | * | |
78fb7466 PE |
6 | * Copyright 2007 OpenVZ SWsoft Inc |
7 | * Author: Pavel Emelianov <xemul@openvz.org> | |
8 | * | |
2e72b634 KS |
9 | * Memory thresholds |
10 | * Copyright (C) 2009 Nokia Corporation | |
11 | * Author: Kirill A. Shutemov | |
12 | * | |
8cdea7c0 BS |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License as published by | |
15 | * the Free Software Foundation; either version 2 of the License, or | |
16 | * (at your option) any later version. | |
17 | * | |
18 | * This program is distributed in the hope that it will be useful, | |
19 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
21 | * GNU General Public License for more details. | |
22 | */ | |
23 | ||
24 | #include <linux/res_counter.h> | |
25 | #include <linux/memcontrol.h> | |
26 | #include <linux/cgroup.h> | |
78fb7466 | 27 | #include <linux/mm.h> |
4ffef5fe | 28 | #include <linux/hugetlb.h> |
d13d1443 | 29 | #include <linux/pagemap.h> |
d52aa412 | 30 | #include <linux/smp.h> |
8a9f3ccd | 31 | #include <linux/page-flags.h> |
66e1707b | 32 | #include <linux/backing-dev.h> |
8a9f3ccd BS |
33 | #include <linux/bit_spinlock.h> |
34 | #include <linux/rcupdate.h> | |
e222432b | 35 | #include <linux/limits.h> |
8c7c6e34 | 36 | #include <linux/mutex.h> |
f64c3f54 | 37 | #include <linux/rbtree.h> |
072441e2 | 38 | #include <linux/shmem_fs.h> |
b6ac57d5 | 39 | #include <linux/slab.h> |
66e1707b | 40 | #include <linux/swap.h> |
02491447 | 41 | #include <linux/swapops.h> |
66e1707b | 42 | #include <linux/spinlock.h> |
2e72b634 KS |
43 | #include <linux/eventfd.h> |
44 | #include <linux/sort.h> | |
66e1707b | 45 | #include <linux/fs.h> |
d2ceb9b7 | 46 | #include <linux/seq_file.h> |
33327948 | 47 | #include <linux/vmalloc.h> |
b69408e8 | 48 | #include <linux/mm_inline.h> |
52d4b9ac | 49 | #include <linux/page_cgroup.h> |
cdec2e42 | 50 | #include <linux/cpu.h> |
158e0a2d | 51 | #include <linux/oom.h> |
08e552c6 | 52 | #include "internal.h" |
8cdea7c0 | 53 | |
8697d331 BS |
54 | #include <asm/uaccess.h> |
55 | ||
cc8e970c KM |
56 | #include <trace/events/vmscan.h> |
57 | ||
a181b0e8 | 58 | struct cgroup_subsys mem_cgroup_subsys __read_mostly; |
a181b0e8 | 59 | #define MEM_CGROUP_RECLAIM_RETRIES 5 |
4b3bde4c | 60 | struct mem_cgroup *root_mem_cgroup __read_mostly; |
8cdea7c0 | 61 | |
c077719b | 62 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
338c8431 | 63 | /* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */ |
c077719b | 64 | int do_swap_account __read_mostly; |
a42c390c MH |
65 | |
66 | /* for remember boot option*/ | |
67 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED | |
68 | static int really_do_swap_account __initdata = 1; | |
69 | #else | |
70 | static int really_do_swap_account __initdata = 0; | |
71 | #endif | |
72 | ||
c077719b KH |
73 | #else |
74 | #define do_swap_account (0) | |
75 | #endif | |
76 | ||
77 | ||
d52aa412 KH |
78 | /* |
79 | * Statistics for memory cgroup. | |
80 | */ | |
81 | enum mem_cgroup_stat_index { | |
82 | /* | |
83 | * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss. | |
84 | */ | |
85 | MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */ | |
d69b042f | 86 | MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */ |
d8046582 | 87 | MEM_CGROUP_STAT_FILE_MAPPED, /* # of pages charged as file rss */ |
0c3e73e8 | 88 | MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */ |
711d3d2c | 89 | MEM_CGROUP_STAT_DATA, /* end of data requires synchronization */ |
32047e2a | 90 | MEM_CGROUP_ON_MOVE, /* someone is moving account between groups */ |
d52aa412 KH |
91 | MEM_CGROUP_STAT_NSTATS, |
92 | }; | |
93 | ||
e9f8974f JW |
94 | enum mem_cgroup_events_index { |
95 | MEM_CGROUP_EVENTS_PGPGIN, /* # of pages paged in */ | |
96 | MEM_CGROUP_EVENTS_PGPGOUT, /* # of pages paged out */ | |
97 | MEM_CGROUP_EVENTS_COUNT, /* # of pages paged in/out */ | |
456f998e YH |
98 | MEM_CGROUP_EVENTS_PGFAULT, /* # of page-faults */ |
99 | MEM_CGROUP_EVENTS_PGMAJFAULT, /* # of major page-faults */ | |
e9f8974f JW |
100 | MEM_CGROUP_EVENTS_NSTATS, |
101 | }; | |
7a159cc9 JW |
102 | /* |
103 | * Per memcg event counter is incremented at every pagein/pageout. With THP, | |
104 | * it will be incremated by the number of pages. This counter is used for | |
105 | * for trigger some periodic events. This is straightforward and better | |
106 | * than using jiffies etc. to handle periodic memcg event. | |
107 | */ | |
108 | enum mem_cgroup_events_target { | |
109 | MEM_CGROUP_TARGET_THRESH, | |
110 | MEM_CGROUP_TARGET_SOFTLIMIT, | |
453a9bf3 | 111 | MEM_CGROUP_TARGET_NUMAINFO, |
7a159cc9 JW |
112 | MEM_CGROUP_NTARGETS, |
113 | }; | |
114 | #define THRESHOLDS_EVENTS_TARGET (128) | |
115 | #define SOFTLIMIT_EVENTS_TARGET (1024) | |
453a9bf3 | 116 | #define NUMAINFO_EVENTS_TARGET (1024) |
e9f8974f | 117 | |
d52aa412 | 118 | struct mem_cgroup_stat_cpu { |
7a159cc9 | 119 | long count[MEM_CGROUP_STAT_NSTATS]; |
e9f8974f | 120 | unsigned long events[MEM_CGROUP_EVENTS_NSTATS]; |
7a159cc9 | 121 | unsigned long targets[MEM_CGROUP_NTARGETS]; |
d52aa412 KH |
122 | }; |
123 | ||
6d12e2d8 KH |
124 | /* |
125 | * per-zone information in memory controller. | |
126 | */ | |
6d12e2d8 | 127 | struct mem_cgroup_per_zone { |
072c56c1 KH |
128 | /* |
129 | * spin_lock to protect the per cgroup LRU | |
130 | */ | |
b69408e8 CL |
131 | struct list_head lists[NR_LRU_LISTS]; |
132 | unsigned long count[NR_LRU_LISTS]; | |
3e2f41f1 KM |
133 | |
134 | struct zone_reclaim_stat reclaim_stat; | |
f64c3f54 BS |
135 | struct rb_node tree_node; /* RB tree node */ |
136 | unsigned long long usage_in_excess;/* Set to the value by which */ | |
137 | /* the soft limit is exceeded*/ | |
138 | bool on_tree; | |
4e416953 BS |
139 | struct mem_cgroup *mem; /* Back pointer, we cannot */ |
140 | /* use container_of */ | |
6d12e2d8 KH |
141 | }; |
142 | /* Macro for accessing counter */ | |
143 | #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)]) | |
144 | ||
145 | struct mem_cgroup_per_node { | |
146 | struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES]; | |
147 | }; | |
148 | ||
149 | struct mem_cgroup_lru_info { | |
150 | struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES]; | |
151 | }; | |
152 | ||
f64c3f54 BS |
153 | /* |
154 | * Cgroups above their limits are maintained in a RB-Tree, independent of | |
155 | * their hierarchy representation | |
156 | */ | |
157 | ||
158 | struct mem_cgroup_tree_per_zone { | |
159 | struct rb_root rb_root; | |
160 | spinlock_t lock; | |
161 | }; | |
162 | ||
163 | struct mem_cgroup_tree_per_node { | |
164 | struct mem_cgroup_tree_per_zone rb_tree_per_zone[MAX_NR_ZONES]; | |
165 | }; | |
166 | ||
167 | struct mem_cgroup_tree { | |
168 | struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; | |
169 | }; | |
170 | ||
171 | static struct mem_cgroup_tree soft_limit_tree __read_mostly; | |
172 | ||
2e72b634 KS |
173 | struct mem_cgroup_threshold { |
174 | struct eventfd_ctx *eventfd; | |
175 | u64 threshold; | |
176 | }; | |
177 | ||
9490ff27 | 178 | /* For threshold */ |
2e72b634 KS |
179 | struct mem_cgroup_threshold_ary { |
180 | /* An array index points to threshold just below usage. */ | |
5407a562 | 181 | int current_threshold; |
2e72b634 KS |
182 | /* Size of entries[] */ |
183 | unsigned int size; | |
184 | /* Array of thresholds */ | |
185 | struct mem_cgroup_threshold entries[0]; | |
186 | }; | |
2c488db2 KS |
187 | |
188 | struct mem_cgroup_thresholds { | |
189 | /* Primary thresholds array */ | |
190 | struct mem_cgroup_threshold_ary *primary; | |
191 | /* | |
192 | * Spare threshold array. | |
193 | * This is needed to make mem_cgroup_unregister_event() "never fail". | |
194 | * It must be able to store at least primary->size - 1 entries. | |
195 | */ | |
196 | struct mem_cgroup_threshold_ary *spare; | |
197 | }; | |
198 | ||
9490ff27 KH |
199 | /* for OOM */ |
200 | struct mem_cgroup_eventfd_list { | |
201 | struct list_head list; | |
202 | struct eventfd_ctx *eventfd; | |
203 | }; | |
2e72b634 | 204 | |
2e72b634 | 205 | static void mem_cgroup_threshold(struct mem_cgroup *mem); |
9490ff27 | 206 | static void mem_cgroup_oom_notify(struct mem_cgroup *mem); |
2e72b634 | 207 | |
8cdea7c0 BS |
208 | /* |
209 | * The memory controller data structure. The memory controller controls both | |
210 | * page cache and RSS per cgroup. We would eventually like to provide | |
211 | * statistics based on the statistics developed by Rik Van Riel for clock-pro, | |
212 | * to help the administrator determine what knobs to tune. | |
213 | * | |
214 | * TODO: Add a water mark for the memory controller. Reclaim will begin when | |
8a9f3ccd BS |
215 | * we hit the water mark. May be even add a low water mark, such that |
216 | * no reclaim occurs from a cgroup at it's low water mark, this is | |
217 | * a feature that will be implemented much later in the future. | |
8cdea7c0 BS |
218 | */ |
219 | struct mem_cgroup { | |
220 | struct cgroup_subsys_state css; | |
221 | /* | |
222 | * the counter to account for memory usage | |
223 | */ | |
224 | struct res_counter res; | |
8c7c6e34 KH |
225 | /* |
226 | * the counter to account for mem+swap usage. | |
227 | */ | |
228 | struct res_counter memsw; | |
78fb7466 PE |
229 | /* |
230 | * Per cgroup active and inactive list, similar to the | |
231 | * per zone LRU lists. | |
78fb7466 | 232 | */ |
6d12e2d8 | 233 | struct mem_cgroup_lru_info info; |
6d61ef40 | 234 | /* |
af901ca1 | 235 | * While reclaiming in a hierarchy, we cache the last child we |
04046e1a | 236 | * reclaimed from. |
6d61ef40 | 237 | */ |
04046e1a | 238 | int last_scanned_child; |
889976db YH |
239 | int last_scanned_node; |
240 | #if MAX_NUMNODES > 1 | |
241 | nodemask_t scan_nodes; | |
453a9bf3 KH |
242 | atomic_t numainfo_events; |
243 | atomic_t numainfo_updating; | |
889976db | 244 | #endif |
18f59ea7 BS |
245 | /* |
246 | * Should the accounting and control be hierarchical, per subtree? | |
247 | */ | |
248 | bool use_hierarchy; | |
79dfdacc MH |
249 | |
250 | bool oom_lock; | |
251 | atomic_t under_oom; | |
252 | ||
8c7c6e34 | 253 | atomic_t refcnt; |
14797e23 | 254 | |
1f4c025b | 255 | int swappiness; |
3c11ecf4 KH |
256 | /* OOM-Killer disable */ |
257 | int oom_kill_disable; | |
a7885eb8 | 258 | |
22a668d7 KH |
259 | /* set when res.limit == memsw.limit */ |
260 | bool memsw_is_minimum; | |
261 | ||
2e72b634 KS |
262 | /* protect arrays of thresholds */ |
263 | struct mutex thresholds_lock; | |
264 | ||
265 | /* thresholds for memory usage. RCU-protected */ | |
2c488db2 | 266 | struct mem_cgroup_thresholds thresholds; |
907860ed | 267 | |
2e72b634 | 268 | /* thresholds for mem+swap usage. RCU-protected */ |
2c488db2 | 269 | struct mem_cgroup_thresholds memsw_thresholds; |
907860ed | 270 | |
9490ff27 KH |
271 | /* For oom notifier event fd */ |
272 | struct list_head oom_notify; | |
273 | ||
7dc74be0 DN |
274 | /* |
275 | * Should we move charges of a task when a task is moved into this | |
276 | * mem_cgroup ? And what type of charges should we move ? | |
277 | */ | |
278 | unsigned long move_charge_at_immigrate; | |
d52aa412 | 279 | /* |
c62b1a3b | 280 | * percpu counter. |
d52aa412 | 281 | */ |
c62b1a3b | 282 | struct mem_cgroup_stat_cpu *stat; |
711d3d2c KH |
283 | /* |
284 | * used when a cpu is offlined or other synchronizations | |
285 | * See mem_cgroup_read_stat(). | |
286 | */ | |
287 | struct mem_cgroup_stat_cpu nocpu_base; | |
288 | spinlock_t pcp_counter_lock; | |
8cdea7c0 BS |
289 | }; |
290 | ||
7dc74be0 DN |
291 | /* Stuffs for move charges at task migration. */ |
292 | /* | |
293 | * Types of charges to be moved. "move_charge_at_immitgrate" is treated as a | |
294 | * left-shifted bitmap of these types. | |
295 | */ | |
296 | enum move_type { | |
4ffef5fe | 297 | MOVE_CHARGE_TYPE_ANON, /* private anonymous page and swap of it */ |
87946a72 | 298 | MOVE_CHARGE_TYPE_FILE, /* file page(including tmpfs) and swap of it */ |
7dc74be0 DN |
299 | NR_MOVE_TYPE, |
300 | }; | |
301 | ||
4ffef5fe DN |
302 | /* "mc" and its members are protected by cgroup_mutex */ |
303 | static struct move_charge_struct { | |
b1dd693e | 304 | spinlock_t lock; /* for from, to */ |
4ffef5fe DN |
305 | struct mem_cgroup *from; |
306 | struct mem_cgroup *to; | |
307 | unsigned long precharge; | |
854ffa8d | 308 | unsigned long moved_charge; |
483c30b5 | 309 | unsigned long moved_swap; |
8033b97c DN |
310 | struct task_struct *moving_task; /* a task moving charges */ |
311 | wait_queue_head_t waitq; /* a waitq for other context */ | |
312 | } mc = { | |
2bd9bb20 | 313 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
314 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
315 | }; | |
4ffef5fe | 316 | |
90254a65 DN |
317 | static bool move_anon(void) |
318 | { | |
319 | return test_bit(MOVE_CHARGE_TYPE_ANON, | |
320 | &mc.to->move_charge_at_immigrate); | |
321 | } | |
322 | ||
87946a72 DN |
323 | static bool move_file(void) |
324 | { | |
325 | return test_bit(MOVE_CHARGE_TYPE_FILE, | |
326 | &mc.to->move_charge_at_immigrate); | |
327 | } | |
328 | ||
4e416953 BS |
329 | /* |
330 | * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft | |
331 | * limit reclaim to prevent infinite loops, if they ever occur. | |
332 | */ | |
333 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS (100) | |
334 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS (2) | |
335 | ||
217bc319 KH |
336 | enum charge_type { |
337 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, | |
338 | MEM_CGROUP_CHARGE_TYPE_MAPPED, | |
4f98a2fe | 339 | MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ |
c05555b5 | 340 | MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ |
d13d1443 | 341 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
8a9478ca | 342 | MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ |
c05555b5 KH |
343 | NR_CHARGE_TYPE, |
344 | }; | |
345 | ||
8c7c6e34 KH |
346 | /* for encoding cft->private value on file */ |
347 | #define _MEM (0) | |
348 | #define _MEMSWAP (1) | |
9490ff27 | 349 | #define _OOM_TYPE (2) |
8c7c6e34 KH |
350 | #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val)) |
351 | #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff) | |
352 | #define MEMFILE_ATTR(val) ((val) & 0xffff) | |
9490ff27 KH |
353 | /* Used for OOM nofiier */ |
354 | #define OOM_CONTROL (0) | |
8c7c6e34 | 355 | |
75822b44 BS |
356 | /* |
357 | * Reclaim flags for mem_cgroup_hierarchical_reclaim | |
358 | */ | |
359 | #define MEM_CGROUP_RECLAIM_NOSWAP_BIT 0x0 | |
360 | #define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT) | |
361 | #define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1 | |
362 | #define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT) | |
4e416953 BS |
363 | #define MEM_CGROUP_RECLAIM_SOFT_BIT 0x2 |
364 | #define MEM_CGROUP_RECLAIM_SOFT (1 << MEM_CGROUP_RECLAIM_SOFT_BIT) | |
75822b44 | 365 | |
8c7c6e34 KH |
366 | static void mem_cgroup_get(struct mem_cgroup *mem); |
367 | static void mem_cgroup_put(struct mem_cgroup *mem); | |
7bcc1bb1 | 368 | static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem); |
26fe6168 | 369 | static void drain_all_stock_async(struct mem_cgroup *mem); |
8c7c6e34 | 370 | |
f64c3f54 BS |
371 | static struct mem_cgroup_per_zone * |
372 | mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid) | |
373 | { | |
374 | return &mem->info.nodeinfo[nid]->zoneinfo[zid]; | |
375 | } | |
376 | ||
d324236b WF |
377 | struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *mem) |
378 | { | |
379 | return &mem->css; | |
380 | } | |
381 | ||
f64c3f54 | 382 | static struct mem_cgroup_per_zone * |
97a6c37b | 383 | page_cgroup_zoneinfo(struct mem_cgroup *mem, struct page *page) |
f64c3f54 | 384 | { |
97a6c37b JW |
385 | int nid = page_to_nid(page); |
386 | int zid = page_zonenum(page); | |
f64c3f54 | 387 | |
f64c3f54 BS |
388 | return mem_cgroup_zoneinfo(mem, nid, zid); |
389 | } | |
390 | ||
391 | static struct mem_cgroup_tree_per_zone * | |
392 | soft_limit_tree_node_zone(int nid, int zid) | |
393 | { | |
394 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
395 | } | |
396 | ||
397 | static struct mem_cgroup_tree_per_zone * | |
398 | soft_limit_tree_from_page(struct page *page) | |
399 | { | |
400 | int nid = page_to_nid(page); | |
401 | int zid = page_zonenum(page); | |
402 | ||
403 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
404 | } | |
405 | ||
406 | static void | |
4e416953 | 407 | __mem_cgroup_insert_exceeded(struct mem_cgroup *mem, |
f64c3f54 | 408 | struct mem_cgroup_per_zone *mz, |
ef8745c1 KH |
409 | struct mem_cgroup_tree_per_zone *mctz, |
410 | unsigned long long new_usage_in_excess) | |
f64c3f54 BS |
411 | { |
412 | struct rb_node **p = &mctz->rb_root.rb_node; | |
413 | struct rb_node *parent = NULL; | |
414 | struct mem_cgroup_per_zone *mz_node; | |
415 | ||
416 | if (mz->on_tree) | |
417 | return; | |
418 | ||
ef8745c1 KH |
419 | mz->usage_in_excess = new_usage_in_excess; |
420 | if (!mz->usage_in_excess) | |
421 | return; | |
f64c3f54 BS |
422 | while (*p) { |
423 | parent = *p; | |
424 | mz_node = rb_entry(parent, struct mem_cgroup_per_zone, | |
425 | tree_node); | |
426 | if (mz->usage_in_excess < mz_node->usage_in_excess) | |
427 | p = &(*p)->rb_left; | |
428 | /* | |
429 | * We can't avoid mem cgroups that are over their soft | |
430 | * limit by the same amount | |
431 | */ | |
432 | else if (mz->usage_in_excess >= mz_node->usage_in_excess) | |
433 | p = &(*p)->rb_right; | |
434 | } | |
435 | rb_link_node(&mz->tree_node, parent, p); | |
436 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
437 | mz->on_tree = true; | |
4e416953 BS |
438 | } |
439 | ||
440 | static void | |
441 | __mem_cgroup_remove_exceeded(struct mem_cgroup *mem, | |
442 | struct mem_cgroup_per_zone *mz, | |
443 | struct mem_cgroup_tree_per_zone *mctz) | |
444 | { | |
445 | if (!mz->on_tree) | |
446 | return; | |
447 | rb_erase(&mz->tree_node, &mctz->rb_root); | |
448 | mz->on_tree = false; | |
449 | } | |
450 | ||
f64c3f54 BS |
451 | static void |
452 | mem_cgroup_remove_exceeded(struct mem_cgroup *mem, | |
453 | struct mem_cgroup_per_zone *mz, | |
454 | struct mem_cgroup_tree_per_zone *mctz) | |
455 | { | |
456 | spin_lock(&mctz->lock); | |
4e416953 | 457 | __mem_cgroup_remove_exceeded(mem, mz, mctz); |
f64c3f54 BS |
458 | spin_unlock(&mctz->lock); |
459 | } | |
460 | ||
f64c3f54 BS |
461 | |
462 | static void mem_cgroup_update_tree(struct mem_cgroup *mem, struct page *page) | |
463 | { | |
ef8745c1 | 464 | unsigned long long excess; |
f64c3f54 BS |
465 | struct mem_cgroup_per_zone *mz; |
466 | struct mem_cgroup_tree_per_zone *mctz; | |
4e649152 KH |
467 | int nid = page_to_nid(page); |
468 | int zid = page_zonenum(page); | |
f64c3f54 BS |
469 | mctz = soft_limit_tree_from_page(page); |
470 | ||
471 | /* | |
4e649152 KH |
472 | * Necessary to update all ancestors when hierarchy is used. |
473 | * because their event counter is not touched. | |
f64c3f54 | 474 | */ |
4e649152 KH |
475 | for (; mem; mem = parent_mem_cgroup(mem)) { |
476 | mz = mem_cgroup_zoneinfo(mem, nid, zid); | |
ef8745c1 | 477 | excess = res_counter_soft_limit_excess(&mem->res); |
4e649152 KH |
478 | /* |
479 | * We have to update the tree if mz is on RB-tree or | |
480 | * mem is over its softlimit. | |
481 | */ | |
ef8745c1 | 482 | if (excess || mz->on_tree) { |
4e649152 KH |
483 | spin_lock(&mctz->lock); |
484 | /* if on-tree, remove it */ | |
485 | if (mz->on_tree) | |
486 | __mem_cgroup_remove_exceeded(mem, mz, mctz); | |
487 | /* | |
ef8745c1 KH |
488 | * Insert again. mz->usage_in_excess will be updated. |
489 | * If excess is 0, no tree ops. | |
4e649152 | 490 | */ |
ef8745c1 | 491 | __mem_cgroup_insert_exceeded(mem, mz, mctz, excess); |
4e649152 KH |
492 | spin_unlock(&mctz->lock); |
493 | } | |
f64c3f54 BS |
494 | } |
495 | } | |
496 | ||
497 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *mem) | |
498 | { | |
499 | int node, zone; | |
500 | struct mem_cgroup_per_zone *mz; | |
501 | struct mem_cgroup_tree_per_zone *mctz; | |
502 | ||
503 | for_each_node_state(node, N_POSSIBLE) { | |
504 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
505 | mz = mem_cgroup_zoneinfo(mem, node, zone); | |
506 | mctz = soft_limit_tree_node_zone(node, zone); | |
507 | mem_cgroup_remove_exceeded(mem, mz, mctz); | |
508 | } | |
509 | } | |
510 | } | |
511 | ||
4e416953 BS |
512 | static struct mem_cgroup_per_zone * |
513 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
514 | { | |
515 | struct rb_node *rightmost = NULL; | |
26251eaf | 516 | struct mem_cgroup_per_zone *mz; |
4e416953 BS |
517 | |
518 | retry: | |
26251eaf | 519 | mz = NULL; |
4e416953 BS |
520 | rightmost = rb_last(&mctz->rb_root); |
521 | if (!rightmost) | |
522 | goto done; /* Nothing to reclaim from */ | |
523 | ||
524 | mz = rb_entry(rightmost, struct mem_cgroup_per_zone, tree_node); | |
525 | /* | |
526 | * Remove the node now but someone else can add it back, | |
527 | * we will to add it back at the end of reclaim to its correct | |
528 | * position in the tree. | |
529 | */ | |
530 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); | |
531 | if (!res_counter_soft_limit_excess(&mz->mem->res) || | |
532 | !css_tryget(&mz->mem->css)) | |
533 | goto retry; | |
534 | done: | |
535 | return mz; | |
536 | } | |
537 | ||
538 | static struct mem_cgroup_per_zone * | |
539 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
540 | { | |
541 | struct mem_cgroup_per_zone *mz; | |
542 | ||
543 | spin_lock(&mctz->lock); | |
544 | mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
545 | spin_unlock(&mctz->lock); | |
546 | return mz; | |
547 | } | |
548 | ||
711d3d2c KH |
549 | /* |
550 | * Implementation Note: reading percpu statistics for memcg. | |
551 | * | |
552 | * Both of vmstat[] and percpu_counter has threshold and do periodic | |
553 | * synchronization to implement "quick" read. There are trade-off between | |
554 | * reading cost and precision of value. Then, we may have a chance to implement | |
555 | * a periodic synchronizion of counter in memcg's counter. | |
556 | * | |
557 | * But this _read() function is used for user interface now. The user accounts | |
558 | * memory usage by memory cgroup and he _always_ requires exact value because | |
559 | * he accounts memory. Even if we provide quick-and-fuzzy read, we always | |
560 | * have to visit all online cpus and make sum. So, for now, unnecessary | |
561 | * synchronization is not implemented. (just implemented for cpu hotplug) | |
562 | * | |
563 | * If there are kernel internal actions which can make use of some not-exact | |
564 | * value, and reading all cpu value can be performance bottleneck in some | |
565 | * common workload, threashold and synchonization as vmstat[] should be | |
566 | * implemented. | |
567 | */ | |
7a159cc9 JW |
568 | static long mem_cgroup_read_stat(struct mem_cgroup *mem, |
569 | enum mem_cgroup_stat_index idx) | |
c62b1a3b | 570 | { |
7a159cc9 | 571 | long val = 0; |
c62b1a3b | 572 | int cpu; |
c62b1a3b | 573 | |
711d3d2c KH |
574 | get_online_cpus(); |
575 | for_each_online_cpu(cpu) | |
c62b1a3b | 576 | val += per_cpu(mem->stat->count[idx], cpu); |
711d3d2c KH |
577 | #ifdef CONFIG_HOTPLUG_CPU |
578 | spin_lock(&mem->pcp_counter_lock); | |
579 | val += mem->nocpu_base.count[idx]; | |
580 | spin_unlock(&mem->pcp_counter_lock); | |
581 | #endif | |
582 | put_online_cpus(); | |
c62b1a3b KH |
583 | return val; |
584 | } | |
585 | ||
0c3e73e8 BS |
586 | static void mem_cgroup_swap_statistics(struct mem_cgroup *mem, |
587 | bool charge) | |
588 | { | |
589 | int val = (charge) ? 1 : -1; | |
c62b1a3b | 590 | this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_SWAPOUT], val); |
0c3e73e8 BS |
591 | } |
592 | ||
456f998e YH |
593 | void mem_cgroup_pgfault(struct mem_cgroup *mem, int val) |
594 | { | |
595 | this_cpu_add(mem->stat->events[MEM_CGROUP_EVENTS_PGFAULT], val); | |
596 | } | |
597 | ||
598 | void mem_cgroup_pgmajfault(struct mem_cgroup *mem, int val) | |
599 | { | |
600 | this_cpu_add(mem->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT], val); | |
601 | } | |
602 | ||
e9f8974f JW |
603 | static unsigned long mem_cgroup_read_events(struct mem_cgroup *mem, |
604 | enum mem_cgroup_events_index idx) | |
605 | { | |
606 | unsigned long val = 0; | |
607 | int cpu; | |
608 | ||
609 | for_each_online_cpu(cpu) | |
610 | val += per_cpu(mem->stat->events[idx], cpu); | |
611 | #ifdef CONFIG_HOTPLUG_CPU | |
612 | spin_lock(&mem->pcp_counter_lock); | |
613 | val += mem->nocpu_base.events[idx]; | |
614 | spin_unlock(&mem->pcp_counter_lock); | |
615 | #endif | |
616 | return val; | |
617 | } | |
618 | ||
c05555b5 | 619 | static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, |
e401f176 | 620 | bool file, int nr_pages) |
d52aa412 | 621 | { |
c62b1a3b KH |
622 | preempt_disable(); |
623 | ||
e401f176 KH |
624 | if (file) |
625 | __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_CACHE], nr_pages); | |
d52aa412 | 626 | else |
e401f176 | 627 | __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_RSS], nr_pages); |
55e462b0 | 628 | |
e401f176 KH |
629 | /* pagein of a big page is an event. So, ignore page size */ |
630 | if (nr_pages > 0) | |
e9f8974f | 631 | __this_cpu_inc(mem->stat->events[MEM_CGROUP_EVENTS_PGPGIN]); |
3751d604 | 632 | else { |
e9f8974f | 633 | __this_cpu_inc(mem->stat->events[MEM_CGROUP_EVENTS_PGPGOUT]); |
3751d604 KH |
634 | nr_pages = -nr_pages; /* for event */ |
635 | } | |
e401f176 | 636 | |
e9f8974f | 637 | __this_cpu_add(mem->stat->events[MEM_CGROUP_EVENTS_COUNT], nr_pages); |
2e72b634 | 638 | |
c62b1a3b | 639 | preempt_enable(); |
6d12e2d8 KH |
640 | } |
641 | ||
bb2a0de9 KH |
642 | unsigned long |
643 | mem_cgroup_zone_nr_lru_pages(struct mem_cgroup *mem, int nid, int zid, | |
644 | unsigned int lru_mask) | |
889976db YH |
645 | { |
646 | struct mem_cgroup_per_zone *mz; | |
bb2a0de9 KH |
647 | enum lru_list l; |
648 | unsigned long ret = 0; | |
649 | ||
650 | mz = mem_cgroup_zoneinfo(mem, nid, zid); | |
651 | ||
652 | for_each_lru(l) { | |
653 | if (BIT(l) & lru_mask) | |
654 | ret += MEM_CGROUP_ZSTAT(mz, l); | |
655 | } | |
656 | return ret; | |
657 | } | |
658 | ||
659 | static unsigned long | |
660 | mem_cgroup_node_nr_lru_pages(struct mem_cgroup *mem, | |
661 | int nid, unsigned int lru_mask) | |
662 | { | |
889976db YH |
663 | u64 total = 0; |
664 | int zid; | |
665 | ||
bb2a0de9 KH |
666 | for (zid = 0; zid < MAX_NR_ZONES; zid++) |
667 | total += mem_cgroup_zone_nr_lru_pages(mem, nid, zid, lru_mask); | |
668 | ||
889976db YH |
669 | return total; |
670 | } | |
bb2a0de9 KH |
671 | |
672 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *mem, | |
673 | unsigned int lru_mask) | |
6d12e2d8 | 674 | { |
889976db | 675 | int nid; |
6d12e2d8 KH |
676 | u64 total = 0; |
677 | ||
bb2a0de9 KH |
678 | for_each_node_state(nid, N_HIGH_MEMORY) |
679 | total += mem_cgroup_node_nr_lru_pages(mem, nid, lru_mask); | |
6d12e2d8 | 680 | return total; |
d52aa412 KH |
681 | } |
682 | ||
7a159cc9 JW |
683 | static bool __memcg_event_check(struct mem_cgroup *mem, int target) |
684 | { | |
685 | unsigned long val, next; | |
686 | ||
687 | val = this_cpu_read(mem->stat->events[MEM_CGROUP_EVENTS_COUNT]); | |
688 | next = this_cpu_read(mem->stat->targets[target]); | |
689 | /* from time_after() in jiffies.h */ | |
690 | return ((long)next - (long)val < 0); | |
691 | } | |
692 | ||
693 | static void __mem_cgroup_target_update(struct mem_cgroup *mem, int target) | |
d2265e6f | 694 | { |
7a159cc9 | 695 | unsigned long val, next; |
d2265e6f | 696 | |
e9f8974f | 697 | val = this_cpu_read(mem->stat->events[MEM_CGROUP_EVENTS_COUNT]); |
d2265e6f | 698 | |
7a159cc9 JW |
699 | switch (target) { |
700 | case MEM_CGROUP_TARGET_THRESH: | |
701 | next = val + THRESHOLDS_EVENTS_TARGET; | |
702 | break; | |
703 | case MEM_CGROUP_TARGET_SOFTLIMIT: | |
704 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
705 | break; | |
453a9bf3 KH |
706 | case MEM_CGROUP_TARGET_NUMAINFO: |
707 | next = val + NUMAINFO_EVENTS_TARGET; | |
708 | break; | |
7a159cc9 JW |
709 | default: |
710 | return; | |
711 | } | |
712 | ||
713 | this_cpu_write(mem->stat->targets[target], next); | |
d2265e6f KH |
714 | } |
715 | ||
716 | /* | |
717 | * Check events in order. | |
718 | * | |
719 | */ | |
720 | static void memcg_check_events(struct mem_cgroup *mem, struct page *page) | |
721 | { | |
722 | /* threshold event is triggered in finer grain than soft limit */ | |
7a159cc9 | 723 | if (unlikely(__memcg_event_check(mem, MEM_CGROUP_TARGET_THRESH))) { |
d2265e6f | 724 | mem_cgroup_threshold(mem); |
7a159cc9 JW |
725 | __mem_cgroup_target_update(mem, MEM_CGROUP_TARGET_THRESH); |
726 | if (unlikely(__memcg_event_check(mem, | |
453a9bf3 | 727 | MEM_CGROUP_TARGET_SOFTLIMIT))) { |
d2265e6f | 728 | mem_cgroup_update_tree(mem, page); |
7a159cc9 | 729 | __mem_cgroup_target_update(mem, |
453a9bf3 KH |
730 | MEM_CGROUP_TARGET_SOFTLIMIT); |
731 | } | |
732 | #if MAX_NUMNODES > 1 | |
733 | if (unlikely(__memcg_event_check(mem, | |
734 | MEM_CGROUP_TARGET_NUMAINFO))) { | |
735 | atomic_inc(&mem->numainfo_events); | |
736 | __mem_cgroup_target_update(mem, | |
737 | MEM_CGROUP_TARGET_NUMAINFO); | |
7a159cc9 | 738 | } |
453a9bf3 | 739 | #endif |
d2265e6f KH |
740 | } |
741 | } | |
742 | ||
d5b69e38 | 743 | static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) |
8cdea7c0 BS |
744 | { |
745 | return container_of(cgroup_subsys_state(cont, | |
746 | mem_cgroup_subsys_id), struct mem_cgroup, | |
747 | css); | |
748 | } | |
749 | ||
cf475ad2 | 750 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 751 | { |
31a78f23 BS |
752 | /* |
753 | * mm_update_next_owner() may clear mm->owner to NULL | |
754 | * if it races with swapoff, page migration, etc. | |
755 | * So this can be called with p == NULL. | |
756 | */ | |
757 | if (unlikely(!p)) | |
758 | return NULL; | |
759 | ||
78fb7466 PE |
760 | return container_of(task_subsys_state(p, mem_cgroup_subsys_id), |
761 | struct mem_cgroup, css); | |
762 | } | |
763 | ||
a433658c | 764 | struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) |
54595fe2 KH |
765 | { |
766 | struct mem_cgroup *mem = NULL; | |
0b7f569e KH |
767 | |
768 | if (!mm) | |
769 | return NULL; | |
54595fe2 KH |
770 | /* |
771 | * Because we have no locks, mm->owner's may be being moved to other | |
772 | * cgroup. We use css_tryget() here even if this looks | |
773 | * pessimistic (rather than adding locks here). | |
774 | */ | |
775 | rcu_read_lock(); | |
776 | do { | |
777 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
778 | if (unlikely(!mem)) | |
779 | break; | |
780 | } while (!css_tryget(&mem->css)); | |
781 | rcu_read_unlock(); | |
782 | return mem; | |
783 | } | |
784 | ||
7d74b06f KH |
785 | /* The caller has to guarantee "mem" exists before calling this */ |
786 | static struct mem_cgroup *mem_cgroup_start_loop(struct mem_cgroup *mem) | |
14067bb3 | 787 | { |
711d3d2c KH |
788 | struct cgroup_subsys_state *css; |
789 | int found; | |
790 | ||
791 | if (!mem) /* ROOT cgroup has the smallest ID */ | |
792 | return root_mem_cgroup; /*css_put/get against root is ignored*/ | |
793 | if (!mem->use_hierarchy) { | |
794 | if (css_tryget(&mem->css)) | |
795 | return mem; | |
796 | return NULL; | |
797 | } | |
798 | rcu_read_lock(); | |
799 | /* | |
800 | * searching a memory cgroup which has the smallest ID under given | |
801 | * ROOT cgroup. (ID >= 1) | |
802 | */ | |
803 | css = css_get_next(&mem_cgroup_subsys, 1, &mem->css, &found); | |
804 | if (css && css_tryget(css)) | |
805 | mem = container_of(css, struct mem_cgroup, css); | |
806 | else | |
807 | mem = NULL; | |
808 | rcu_read_unlock(); | |
809 | return mem; | |
7d74b06f KH |
810 | } |
811 | ||
812 | static struct mem_cgroup *mem_cgroup_get_next(struct mem_cgroup *iter, | |
813 | struct mem_cgroup *root, | |
814 | bool cond) | |
815 | { | |
816 | int nextid = css_id(&iter->css) + 1; | |
817 | int found; | |
818 | int hierarchy_used; | |
14067bb3 | 819 | struct cgroup_subsys_state *css; |
14067bb3 | 820 | |
7d74b06f | 821 | hierarchy_used = iter->use_hierarchy; |
14067bb3 | 822 | |
7d74b06f | 823 | css_put(&iter->css); |
711d3d2c KH |
824 | /* If no ROOT, walk all, ignore hierarchy */ |
825 | if (!cond || (root && !hierarchy_used)) | |
7d74b06f | 826 | return NULL; |
14067bb3 | 827 | |
711d3d2c KH |
828 | if (!root) |
829 | root = root_mem_cgroup; | |
830 | ||
7d74b06f KH |
831 | do { |
832 | iter = NULL; | |
14067bb3 | 833 | rcu_read_lock(); |
7d74b06f KH |
834 | |
835 | css = css_get_next(&mem_cgroup_subsys, nextid, | |
836 | &root->css, &found); | |
14067bb3 | 837 | if (css && css_tryget(css)) |
7d74b06f | 838 | iter = container_of(css, struct mem_cgroup, css); |
14067bb3 | 839 | rcu_read_unlock(); |
7d74b06f | 840 | /* If css is NULL, no more cgroups will be found */ |
14067bb3 | 841 | nextid = found + 1; |
7d74b06f | 842 | } while (css && !iter); |
14067bb3 | 843 | |
7d74b06f | 844 | return iter; |
14067bb3 | 845 | } |
7d74b06f KH |
846 | /* |
847 | * for_eacn_mem_cgroup_tree() for visiting all cgroup under tree. Please | |
848 | * be careful that "break" loop is not allowed. We have reference count. | |
849 | * Instead of that modify "cond" to be false and "continue" to exit the loop. | |
850 | */ | |
851 | #define for_each_mem_cgroup_tree_cond(iter, root, cond) \ | |
852 | for (iter = mem_cgroup_start_loop(root);\ | |
853 | iter != NULL;\ | |
854 | iter = mem_cgroup_get_next(iter, root, cond)) | |
855 | ||
856 | #define for_each_mem_cgroup_tree(iter, root) \ | |
857 | for_each_mem_cgroup_tree_cond(iter, root, true) | |
858 | ||
711d3d2c KH |
859 | #define for_each_mem_cgroup_all(iter) \ |
860 | for_each_mem_cgroup_tree_cond(iter, NULL, true) | |
861 | ||
14067bb3 | 862 | |
4b3bde4c BS |
863 | static inline bool mem_cgroup_is_root(struct mem_cgroup *mem) |
864 | { | |
865 | return (mem == root_mem_cgroup); | |
866 | } | |
867 | ||
456f998e YH |
868 | void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) |
869 | { | |
870 | struct mem_cgroup *mem; | |
871 | ||
872 | if (!mm) | |
873 | return; | |
874 | ||
875 | rcu_read_lock(); | |
876 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
877 | if (unlikely(!mem)) | |
878 | goto out; | |
879 | ||
880 | switch (idx) { | |
881 | case PGMAJFAULT: | |
882 | mem_cgroup_pgmajfault(mem, 1); | |
883 | break; | |
884 | case PGFAULT: | |
885 | mem_cgroup_pgfault(mem, 1); | |
886 | break; | |
887 | default: | |
888 | BUG(); | |
889 | } | |
890 | out: | |
891 | rcu_read_unlock(); | |
892 | } | |
893 | EXPORT_SYMBOL(mem_cgroup_count_vm_event); | |
894 | ||
08e552c6 KH |
895 | /* |
896 | * Following LRU functions are allowed to be used without PCG_LOCK. | |
897 | * Operations are called by routine of global LRU independently from memcg. | |
898 | * What we have to take care of here is validness of pc->mem_cgroup. | |
899 | * | |
900 | * Changes to pc->mem_cgroup happens when | |
901 | * 1. charge | |
902 | * 2. moving account | |
903 | * In typical case, "charge" is done before add-to-lru. Exception is SwapCache. | |
904 | * It is added to LRU before charge. | |
905 | * If PCG_USED bit is not set, page_cgroup is not added to this private LRU. | |
906 | * When moving account, the page is not on LRU. It's isolated. | |
907 | */ | |
4f98a2fe | 908 | |
08e552c6 KH |
909 | void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru) |
910 | { | |
911 | struct page_cgroup *pc; | |
08e552c6 | 912 | struct mem_cgroup_per_zone *mz; |
6d12e2d8 | 913 | |
f8d66542 | 914 | if (mem_cgroup_disabled()) |
08e552c6 KH |
915 | return; |
916 | pc = lookup_page_cgroup(page); | |
917 | /* can happen while we handle swapcache. */ | |
4b3bde4c | 918 | if (!TestClearPageCgroupAcctLRU(pc)) |
08e552c6 | 919 | return; |
4b3bde4c | 920 | VM_BUG_ON(!pc->mem_cgroup); |
544122e5 KH |
921 | /* |
922 | * We don't check PCG_USED bit. It's cleared when the "page" is finally | |
923 | * removed from global LRU. | |
924 | */ | |
97a6c37b | 925 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
ece35ca8 KH |
926 | /* huge page split is done under lru_lock. so, we have no races. */ |
927 | MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page); | |
4b3bde4c BS |
928 | if (mem_cgroup_is_root(pc->mem_cgroup)) |
929 | return; | |
930 | VM_BUG_ON(list_empty(&pc->lru)); | |
08e552c6 | 931 | list_del_init(&pc->lru); |
6d12e2d8 KH |
932 | } |
933 | ||
08e552c6 | 934 | void mem_cgroup_del_lru(struct page *page) |
6d12e2d8 | 935 | { |
08e552c6 KH |
936 | mem_cgroup_del_lru_list(page, page_lru(page)); |
937 | } | |
b69408e8 | 938 | |
3f58a829 MK |
939 | /* |
940 | * Writeback is about to end against a page which has been marked for immediate | |
941 | * reclaim. If it still appears to be reclaimable, move it to the tail of the | |
942 | * inactive list. | |
943 | */ | |
944 | void mem_cgroup_rotate_reclaimable_page(struct page *page) | |
945 | { | |
946 | struct mem_cgroup_per_zone *mz; | |
947 | struct page_cgroup *pc; | |
948 | enum lru_list lru = page_lru(page); | |
949 | ||
950 | if (mem_cgroup_disabled()) | |
951 | return; | |
952 | ||
953 | pc = lookup_page_cgroup(page); | |
954 | /* unused or root page is not rotated. */ | |
955 | if (!PageCgroupUsed(pc)) | |
956 | return; | |
957 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ | |
958 | smp_rmb(); | |
959 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
960 | return; | |
97a6c37b | 961 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
3f58a829 MK |
962 | list_move_tail(&pc->lru, &mz->lists[lru]); |
963 | } | |
964 | ||
08e552c6 KH |
965 | void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru) |
966 | { | |
967 | struct mem_cgroup_per_zone *mz; | |
968 | struct page_cgroup *pc; | |
b69408e8 | 969 | |
f8d66542 | 970 | if (mem_cgroup_disabled()) |
08e552c6 | 971 | return; |
6d12e2d8 | 972 | |
08e552c6 | 973 | pc = lookup_page_cgroup(page); |
4b3bde4c | 974 | /* unused or root page is not rotated. */ |
713735b4 JW |
975 | if (!PageCgroupUsed(pc)) |
976 | return; | |
977 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ | |
978 | smp_rmb(); | |
979 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
08e552c6 | 980 | return; |
97a6c37b | 981 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
08e552c6 | 982 | list_move(&pc->lru, &mz->lists[lru]); |
6d12e2d8 KH |
983 | } |
984 | ||
08e552c6 | 985 | void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru) |
66e1707b | 986 | { |
08e552c6 KH |
987 | struct page_cgroup *pc; |
988 | struct mem_cgroup_per_zone *mz; | |
6d12e2d8 | 989 | |
f8d66542 | 990 | if (mem_cgroup_disabled()) |
08e552c6 KH |
991 | return; |
992 | pc = lookup_page_cgroup(page); | |
4b3bde4c | 993 | VM_BUG_ON(PageCgroupAcctLRU(pc)); |
08e552c6 | 994 | if (!PageCgroupUsed(pc)) |
894bc310 | 995 | return; |
713735b4 JW |
996 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
997 | smp_rmb(); | |
97a6c37b | 998 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
ece35ca8 KH |
999 | /* huge page split is done under lru_lock. so, we have no races. */ |
1000 | MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page); | |
4b3bde4c BS |
1001 | SetPageCgroupAcctLRU(pc); |
1002 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
1003 | return; | |
08e552c6 KH |
1004 | list_add(&pc->lru, &mz->lists[lru]); |
1005 | } | |
544122e5 | 1006 | |
08e552c6 | 1007 | /* |
5a6475a4 KH |
1008 | * At handling SwapCache and other FUSE stuff, pc->mem_cgroup may be changed |
1009 | * while it's linked to lru because the page may be reused after it's fully | |
1010 | * uncharged. To handle that, unlink page_cgroup from LRU when charge it again. | |
1011 | * It's done under lock_page and expected that zone->lru_lock isnever held. | |
08e552c6 | 1012 | */ |
5a6475a4 | 1013 | static void mem_cgroup_lru_del_before_commit(struct page *page) |
08e552c6 | 1014 | { |
544122e5 KH |
1015 | unsigned long flags; |
1016 | struct zone *zone = page_zone(page); | |
1017 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
1018 | ||
5a6475a4 KH |
1019 | /* |
1020 | * Doing this check without taking ->lru_lock seems wrong but this | |
1021 | * is safe. Because if page_cgroup's USED bit is unset, the page | |
1022 | * will not be added to any memcg's LRU. If page_cgroup's USED bit is | |
1023 | * set, the commit after this will fail, anyway. | |
1024 | * This all charge/uncharge is done under some mutual execustion. | |
1025 | * So, we don't need to taking care of changes in USED bit. | |
1026 | */ | |
1027 | if (likely(!PageLRU(page))) | |
1028 | return; | |
1029 | ||
544122e5 KH |
1030 | spin_lock_irqsave(&zone->lru_lock, flags); |
1031 | /* | |
1032 | * Forget old LRU when this page_cgroup is *not* used. This Used bit | |
1033 | * is guarded by lock_page() because the page is SwapCache. | |
1034 | */ | |
1035 | if (!PageCgroupUsed(pc)) | |
1036 | mem_cgroup_del_lru_list(page, page_lru(page)); | |
1037 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
08e552c6 KH |
1038 | } |
1039 | ||
5a6475a4 | 1040 | static void mem_cgroup_lru_add_after_commit(struct page *page) |
544122e5 KH |
1041 | { |
1042 | unsigned long flags; | |
1043 | struct zone *zone = page_zone(page); | |
1044 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
1045 | ||
5a6475a4 KH |
1046 | /* taking care of that the page is added to LRU while we commit it */ |
1047 | if (likely(!PageLRU(page))) | |
1048 | return; | |
544122e5 KH |
1049 | spin_lock_irqsave(&zone->lru_lock, flags); |
1050 | /* link when the page is linked to LRU but page_cgroup isn't */ | |
4b3bde4c | 1051 | if (PageLRU(page) && !PageCgroupAcctLRU(pc)) |
544122e5 KH |
1052 | mem_cgroup_add_lru_list(page, page_lru(page)); |
1053 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
1054 | } | |
1055 | ||
1056 | ||
08e552c6 KH |
1057 | void mem_cgroup_move_lists(struct page *page, |
1058 | enum lru_list from, enum lru_list to) | |
1059 | { | |
f8d66542 | 1060 | if (mem_cgroup_disabled()) |
08e552c6 KH |
1061 | return; |
1062 | mem_cgroup_del_lru_list(page, from); | |
1063 | mem_cgroup_add_lru_list(page, to); | |
66e1707b BS |
1064 | } |
1065 | ||
4c4a2214 DR |
1066 | int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem) |
1067 | { | |
1068 | int ret; | |
0b7f569e | 1069 | struct mem_cgroup *curr = NULL; |
158e0a2d | 1070 | struct task_struct *p; |
4c4a2214 | 1071 | |
158e0a2d KH |
1072 | p = find_lock_task_mm(task); |
1073 | if (!p) | |
1074 | return 0; | |
1075 | curr = try_get_mem_cgroup_from_mm(p->mm); | |
1076 | task_unlock(p); | |
0b7f569e KH |
1077 | if (!curr) |
1078 | return 0; | |
d31f56db DN |
1079 | /* |
1080 | * We should check use_hierarchy of "mem" not "curr". Because checking | |
1081 | * use_hierarchy of "curr" here make this function true if hierarchy is | |
1082 | * enabled in "curr" and "curr" is a child of "mem" in *cgroup* | |
1083 | * hierarchy(even if use_hierarchy is disabled in "mem"). | |
1084 | */ | |
1085 | if (mem->use_hierarchy) | |
0b7f569e KH |
1086 | ret = css_is_ancestor(&curr->css, &mem->css); |
1087 | else | |
1088 | ret = (curr == mem); | |
1089 | css_put(&curr->css); | |
4c4a2214 DR |
1090 | return ret; |
1091 | } | |
1092 | ||
c772be93 | 1093 | static int calc_inactive_ratio(struct mem_cgroup *memcg, unsigned long *present_pages) |
14797e23 KM |
1094 | { |
1095 | unsigned long active; | |
1096 | unsigned long inactive; | |
c772be93 KM |
1097 | unsigned long gb; |
1098 | unsigned long inactive_ratio; | |
14797e23 | 1099 | |
bb2a0de9 KH |
1100 | inactive = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_INACTIVE_ANON)); |
1101 | active = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_ACTIVE_ANON)); | |
14797e23 | 1102 | |
c772be93 KM |
1103 | gb = (inactive + active) >> (30 - PAGE_SHIFT); |
1104 | if (gb) | |
1105 | inactive_ratio = int_sqrt(10 * gb); | |
1106 | else | |
1107 | inactive_ratio = 1; | |
1108 | ||
1109 | if (present_pages) { | |
1110 | present_pages[0] = inactive; | |
1111 | present_pages[1] = active; | |
1112 | } | |
1113 | ||
1114 | return inactive_ratio; | |
1115 | } | |
1116 | ||
1117 | int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg) | |
1118 | { | |
1119 | unsigned long active; | |
1120 | unsigned long inactive; | |
1121 | unsigned long present_pages[2]; | |
1122 | unsigned long inactive_ratio; | |
1123 | ||
1124 | inactive_ratio = calc_inactive_ratio(memcg, present_pages); | |
1125 | ||
1126 | inactive = present_pages[0]; | |
1127 | active = present_pages[1]; | |
1128 | ||
1129 | if (inactive * inactive_ratio < active) | |
14797e23 KM |
1130 | return 1; |
1131 | ||
1132 | return 0; | |
1133 | } | |
1134 | ||
56e49d21 RR |
1135 | int mem_cgroup_inactive_file_is_low(struct mem_cgroup *memcg) |
1136 | { | |
1137 | unsigned long active; | |
1138 | unsigned long inactive; | |
1139 | ||
bb2a0de9 KH |
1140 | inactive = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_INACTIVE_FILE)); |
1141 | active = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_ACTIVE_FILE)); | |
56e49d21 RR |
1142 | |
1143 | return (active > inactive); | |
1144 | } | |
1145 | ||
3e2f41f1 KM |
1146 | struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg, |
1147 | struct zone *zone) | |
1148 | { | |
13d7e3a2 | 1149 | int nid = zone_to_nid(zone); |
3e2f41f1 KM |
1150 | int zid = zone_idx(zone); |
1151 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
1152 | ||
1153 | return &mz->reclaim_stat; | |
1154 | } | |
1155 | ||
1156 | struct zone_reclaim_stat * | |
1157 | mem_cgroup_get_reclaim_stat_from_page(struct page *page) | |
1158 | { | |
1159 | struct page_cgroup *pc; | |
1160 | struct mem_cgroup_per_zone *mz; | |
1161 | ||
1162 | if (mem_cgroup_disabled()) | |
1163 | return NULL; | |
1164 | ||
1165 | pc = lookup_page_cgroup(page); | |
bd112db8 DN |
1166 | if (!PageCgroupUsed(pc)) |
1167 | return NULL; | |
713735b4 JW |
1168 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
1169 | smp_rmb(); | |
97a6c37b | 1170 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
3e2f41f1 KM |
1171 | return &mz->reclaim_stat; |
1172 | } | |
1173 | ||
66e1707b BS |
1174 | unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, |
1175 | struct list_head *dst, | |
1176 | unsigned long *scanned, int order, | |
1177 | int mode, struct zone *z, | |
1178 | struct mem_cgroup *mem_cont, | |
4f98a2fe | 1179 | int active, int file) |
66e1707b BS |
1180 | { |
1181 | unsigned long nr_taken = 0; | |
1182 | struct page *page; | |
1183 | unsigned long scan; | |
1184 | LIST_HEAD(pc_list); | |
1185 | struct list_head *src; | |
ff7283fa | 1186 | struct page_cgroup *pc, *tmp; |
13d7e3a2 | 1187 | int nid = zone_to_nid(z); |
1ecaab2b KH |
1188 | int zid = zone_idx(z); |
1189 | struct mem_cgroup_per_zone *mz; | |
b7c46d15 | 1190 | int lru = LRU_FILE * file + active; |
2ffebca6 | 1191 | int ret; |
66e1707b | 1192 | |
cf475ad2 | 1193 | BUG_ON(!mem_cont); |
1ecaab2b | 1194 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); |
b69408e8 | 1195 | src = &mz->lists[lru]; |
66e1707b | 1196 | |
ff7283fa KH |
1197 | scan = 0; |
1198 | list_for_each_entry_safe_reverse(pc, tmp, src, lru) { | |
436c6541 | 1199 | if (scan >= nr_to_scan) |
ff7283fa | 1200 | break; |
08e552c6 | 1201 | |
52d4b9ac KH |
1202 | if (unlikely(!PageCgroupUsed(pc))) |
1203 | continue; | |
5564e88b | 1204 | |
6b3ae58e | 1205 | page = lookup_cgroup_page(pc); |
5564e88b | 1206 | |
436c6541 | 1207 | if (unlikely(!PageLRU(page))) |
ff7283fa | 1208 | continue; |
ff7283fa | 1209 | |
436c6541 | 1210 | scan++; |
2ffebca6 KH |
1211 | ret = __isolate_lru_page(page, mode, file); |
1212 | switch (ret) { | |
1213 | case 0: | |
66e1707b | 1214 | list_move(&page->lru, dst); |
2ffebca6 | 1215 | mem_cgroup_del_lru(page); |
2c888cfb | 1216 | nr_taken += hpage_nr_pages(page); |
2ffebca6 KH |
1217 | break; |
1218 | case -EBUSY: | |
1219 | /* we don't affect global LRU but rotate in our LRU */ | |
1220 | mem_cgroup_rotate_lru_list(page, page_lru(page)); | |
1221 | break; | |
1222 | default: | |
1223 | break; | |
66e1707b BS |
1224 | } |
1225 | } | |
1226 | ||
66e1707b | 1227 | *scanned = scan; |
cc8e970c KM |
1228 | |
1229 | trace_mm_vmscan_memcg_isolate(0, nr_to_scan, scan, nr_taken, | |
1230 | 0, 0, 0, mode); | |
1231 | ||
66e1707b BS |
1232 | return nr_taken; |
1233 | } | |
1234 | ||
6d61ef40 BS |
1235 | #define mem_cgroup_from_res_counter(counter, member) \ |
1236 | container_of(counter, struct mem_cgroup, member) | |
1237 | ||
19942822 | 1238 | /** |
9d11ea9f JW |
1239 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
1240 | * @mem: the memory cgroup | |
19942822 | 1241 | * |
9d11ea9f | 1242 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1243 | * pages. |
19942822 | 1244 | */ |
7ec99d62 | 1245 | static unsigned long mem_cgroup_margin(struct mem_cgroup *mem) |
19942822 | 1246 | { |
9d11ea9f JW |
1247 | unsigned long long margin; |
1248 | ||
1249 | margin = res_counter_margin(&mem->res); | |
1250 | if (do_swap_account) | |
1251 | margin = min(margin, res_counter_margin(&mem->memsw)); | |
7ec99d62 | 1252 | return margin >> PAGE_SHIFT; |
19942822 JW |
1253 | } |
1254 | ||
1f4c025b | 1255 | int mem_cgroup_swappiness(struct mem_cgroup *memcg) |
a7885eb8 KM |
1256 | { |
1257 | struct cgroup *cgrp = memcg->css.cgroup; | |
a7885eb8 KM |
1258 | |
1259 | /* root ? */ | |
1260 | if (cgrp->parent == NULL) | |
1261 | return vm_swappiness; | |
1262 | ||
bf1ff263 | 1263 | return memcg->swappiness; |
a7885eb8 KM |
1264 | } |
1265 | ||
32047e2a KH |
1266 | static void mem_cgroup_start_move(struct mem_cgroup *mem) |
1267 | { | |
1268 | int cpu; | |
1489ebad KH |
1269 | |
1270 | get_online_cpus(); | |
1271 | spin_lock(&mem->pcp_counter_lock); | |
1272 | for_each_online_cpu(cpu) | |
32047e2a | 1273 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) += 1; |
1489ebad KH |
1274 | mem->nocpu_base.count[MEM_CGROUP_ON_MOVE] += 1; |
1275 | spin_unlock(&mem->pcp_counter_lock); | |
1276 | put_online_cpus(); | |
32047e2a KH |
1277 | |
1278 | synchronize_rcu(); | |
1279 | } | |
1280 | ||
1281 | static void mem_cgroup_end_move(struct mem_cgroup *mem) | |
1282 | { | |
1283 | int cpu; | |
1284 | ||
1285 | if (!mem) | |
1286 | return; | |
1489ebad KH |
1287 | get_online_cpus(); |
1288 | spin_lock(&mem->pcp_counter_lock); | |
1289 | for_each_online_cpu(cpu) | |
32047e2a | 1290 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) -= 1; |
1489ebad KH |
1291 | mem->nocpu_base.count[MEM_CGROUP_ON_MOVE] -= 1; |
1292 | spin_unlock(&mem->pcp_counter_lock); | |
1293 | put_online_cpus(); | |
32047e2a KH |
1294 | } |
1295 | /* | |
1296 | * 2 routines for checking "mem" is under move_account() or not. | |
1297 | * | |
1298 | * mem_cgroup_stealed() - checking a cgroup is mc.from or not. This is used | |
1299 | * for avoiding race in accounting. If true, | |
1300 | * pc->mem_cgroup may be overwritten. | |
1301 | * | |
1302 | * mem_cgroup_under_move() - checking a cgroup is mc.from or mc.to or | |
1303 | * under hierarchy of moving cgroups. This is for | |
1304 | * waiting at hith-memory prressure caused by "move". | |
1305 | */ | |
1306 | ||
1307 | static bool mem_cgroup_stealed(struct mem_cgroup *mem) | |
1308 | { | |
1309 | VM_BUG_ON(!rcu_read_lock_held()); | |
1310 | return this_cpu_read(mem->stat->count[MEM_CGROUP_ON_MOVE]) > 0; | |
1311 | } | |
4b534334 KH |
1312 | |
1313 | static bool mem_cgroup_under_move(struct mem_cgroup *mem) | |
1314 | { | |
2bd9bb20 KH |
1315 | struct mem_cgroup *from; |
1316 | struct mem_cgroup *to; | |
4b534334 | 1317 | bool ret = false; |
2bd9bb20 KH |
1318 | /* |
1319 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1320 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1321 | */ | |
1322 | spin_lock(&mc.lock); | |
1323 | from = mc.from; | |
1324 | to = mc.to; | |
1325 | if (!from) | |
1326 | goto unlock; | |
1327 | if (from == mem || to == mem | |
1328 | || (mem->use_hierarchy && css_is_ancestor(&from->css, &mem->css)) | |
1329 | || (mem->use_hierarchy && css_is_ancestor(&to->css, &mem->css))) | |
1330 | ret = true; | |
1331 | unlock: | |
1332 | spin_unlock(&mc.lock); | |
4b534334 KH |
1333 | return ret; |
1334 | } | |
1335 | ||
1336 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *mem) | |
1337 | { | |
1338 | if (mc.moving_task && current != mc.moving_task) { | |
1339 | if (mem_cgroup_under_move(mem)) { | |
1340 | DEFINE_WAIT(wait); | |
1341 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1342 | /* moving charge context might have finished. */ | |
1343 | if (mc.moving_task) | |
1344 | schedule(); | |
1345 | finish_wait(&mc.waitq, &wait); | |
1346 | return true; | |
1347 | } | |
1348 | } | |
1349 | return false; | |
1350 | } | |
1351 | ||
e222432b | 1352 | /** |
6a6135b6 | 1353 | * mem_cgroup_print_oom_info: Called from OOM with tasklist_lock held in read mode. |
e222432b BS |
1354 | * @memcg: The memory cgroup that went over limit |
1355 | * @p: Task that is going to be killed | |
1356 | * | |
1357 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1358 | * enabled | |
1359 | */ | |
1360 | void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) | |
1361 | { | |
1362 | struct cgroup *task_cgrp; | |
1363 | struct cgroup *mem_cgrp; | |
1364 | /* | |
1365 | * Need a buffer in BSS, can't rely on allocations. The code relies | |
1366 | * on the assumption that OOM is serialized for memory controller. | |
1367 | * If this assumption is broken, revisit this code. | |
1368 | */ | |
1369 | static char memcg_name[PATH_MAX]; | |
1370 | int ret; | |
1371 | ||
d31f56db | 1372 | if (!memcg || !p) |
e222432b BS |
1373 | return; |
1374 | ||
1375 | ||
1376 | rcu_read_lock(); | |
1377 | ||
1378 | mem_cgrp = memcg->css.cgroup; | |
1379 | task_cgrp = task_cgroup(p, mem_cgroup_subsys_id); | |
1380 | ||
1381 | ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX); | |
1382 | if (ret < 0) { | |
1383 | /* | |
1384 | * Unfortunately, we are unable to convert to a useful name | |
1385 | * But we'll still print out the usage information | |
1386 | */ | |
1387 | rcu_read_unlock(); | |
1388 | goto done; | |
1389 | } | |
1390 | rcu_read_unlock(); | |
1391 | ||
1392 | printk(KERN_INFO "Task in %s killed", memcg_name); | |
1393 | ||
1394 | rcu_read_lock(); | |
1395 | ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX); | |
1396 | if (ret < 0) { | |
1397 | rcu_read_unlock(); | |
1398 | goto done; | |
1399 | } | |
1400 | rcu_read_unlock(); | |
1401 | ||
1402 | /* | |
1403 | * Continues from above, so we don't need an KERN_ level | |
1404 | */ | |
1405 | printk(KERN_CONT " as a result of limit of %s\n", memcg_name); | |
1406 | done: | |
1407 | ||
1408 | printk(KERN_INFO "memory: usage %llukB, limit %llukB, failcnt %llu\n", | |
1409 | res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, | |
1410 | res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, | |
1411 | res_counter_read_u64(&memcg->res, RES_FAILCNT)); | |
1412 | printk(KERN_INFO "memory+swap: usage %llukB, limit %llukB, " | |
1413 | "failcnt %llu\n", | |
1414 | res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, | |
1415 | res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, | |
1416 | res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); | |
1417 | } | |
1418 | ||
81d39c20 KH |
1419 | /* |
1420 | * This function returns the number of memcg under hierarchy tree. Returns | |
1421 | * 1(self count) if no children. | |
1422 | */ | |
1423 | static int mem_cgroup_count_children(struct mem_cgroup *mem) | |
1424 | { | |
1425 | int num = 0; | |
7d74b06f KH |
1426 | struct mem_cgroup *iter; |
1427 | ||
1428 | for_each_mem_cgroup_tree(iter, mem) | |
1429 | num++; | |
81d39c20 KH |
1430 | return num; |
1431 | } | |
1432 | ||
a63d83f4 DR |
1433 | /* |
1434 | * Return the memory (and swap, if configured) limit for a memcg. | |
1435 | */ | |
1436 | u64 mem_cgroup_get_limit(struct mem_cgroup *memcg) | |
1437 | { | |
1438 | u64 limit; | |
1439 | u64 memsw; | |
1440 | ||
f3e8eb70 JW |
1441 | limit = res_counter_read_u64(&memcg->res, RES_LIMIT); |
1442 | limit += total_swap_pages << PAGE_SHIFT; | |
1443 | ||
a63d83f4 DR |
1444 | memsw = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
1445 | /* | |
1446 | * If memsw is finite and limits the amount of swap space available | |
1447 | * to this memcg, return that limit. | |
1448 | */ | |
1449 | return min(limit, memsw); | |
1450 | } | |
1451 | ||
6d61ef40 | 1452 | /* |
04046e1a KH |
1453 | * Visit the first child (need not be the first child as per the ordering |
1454 | * of the cgroup list, since we track last_scanned_child) of @mem and use | |
1455 | * that to reclaim free pages from. | |
1456 | */ | |
1457 | static struct mem_cgroup * | |
1458 | mem_cgroup_select_victim(struct mem_cgroup *root_mem) | |
1459 | { | |
1460 | struct mem_cgroup *ret = NULL; | |
1461 | struct cgroup_subsys_state *css; | |
1462 | int nextid, found; | |
1463 | ||
1464 | if (!root_mem->use_hierarchy) { | |
1465 | css_get(&root_mem->css); | |
1466 | ret = root_mem; | |
1467 | } | |
1468 | ||
1469 | while (!ret) { | |
1470 | rcu_read_lock(); | |
1471 | nextid = root_mem->last_scanned_child + 1; | |
1472 | css = css_get_next(&mem_cgroup_subsys, nextid, &root_mem->css, | |
1473 | &found); | |
1474 | if (css && css_tryget(css)) | |
1475 | ret = container_of(css, struct mem_cgroup, css); | |
1476 | ||
1477 | rcu_read_unlock(); | |
1478 | /* Updates scanning parameter */ | |
04046e1a KH |
1479 | if (!css) { |
1480 | /* this means start scan from ID:1 */ | |
1481 | root_mem->last_scanned_child = 0; | |
1482 | } else | |
1483 | root_mem->last_scanned_child = found; | |
04046e1a KH |
1484 | } |
1485 | ||
1486 | return ret; | |
1487 | } | |
1488 | ||
4d0c066d KH |
1489 | /** |
1490 | * test_mem_cgroup_node_reclaimable | |
1491 | * @mem: the target memcg | |
1492 | * @nid: the node ID to be checked. | |
1493 | * @noswap : specify true here if the user wants flle only information. | |
1494 | * | |
1495 | * This function returns whether the specified memcg contains any | |
1496 | * reclaimable pages on a node. Returns true if there are any reclaimable | |
1497 | * pages in the node. | |
1498 | */ | |
1499 | static bool test_mem_cgroup_node_reclaimable(struct mem_cgroup *mem, | |
1500 | int nid, bool noswap) | |
1501 | { | |
bb2a0de9 | 1502 | if (mem_cgroup_node_nr_lru_pages(mem, nid, LRU_ALL_FILE)) |
4d0c066d KH |
1503 | return true; |
1504 | if (noswap || !total_swap_pages) | |
1505 | return false; | |
bb2a0de9 | 1506 | if (mem_cgroup_node_nr_lru_pages(mem, nid, LRU_ALL_ANON)) |
4d0c066d KH |
1507 | return true; |
1508 | return false; | |
1509 | ||
1510 | } | |
889976db YH |
1511 | #if MAX_NUMNODES > 1 |
1512 | ||
1513 | /* | |
1514 | * Always updating the nodemask is not very good - even if we have an empty | |
1515 | * list or the wrong list here, we can start from some node and traverse all | |
1516 | * nodes based on the zonelist. So update the list loosely once per 10 secs. | |
1517 | * | |
1518 | */ | |
1519 | static void mem_cgroup_may_update_nodemask(struct mem_cgroup *mem) | |
1520 | { | |
1521 | int nid; | |
453a9bf3 KH |
1522 | /* |
1523 | * numainfo_events > 0 means there was at least NUMAINFO_EVENTS_TARGET | |
1524 | * pagein/pageout changes since the last update. | |
1525 | */ | |
1526 | if (!atomic_read(&mem->numainfo_events)) | |
1527 | return; | |
1528 | if (atomic_inc_return(&mem->numainfo_updating) > 1) | |
889976db YH |
1529 | return; |
1530 | ||
889976db YH |
1531 | /* make a nodemask where this memcg uses memory from */ |
1532 | mem->scan_nodes = node_states[N_HIGH_MEMORY]; | |
1533 | ||
1534 | for_each_node_mask(nid, node_states[N_HIGH_MEMORY]) { | |
1535 | ||
4d0c066d KH |
1536 | if (!test_mem_cgroup_node_reclaimable(mem, nid, false)) |
1537 | node_clear(nid, mem->scan_nodes); | |
889976db | 1538 | } |
453a9bf3 KH |
1539 | |
1540 | atomic_set(&mem->numainfo_events, 0); | |
1541 | atomic_set(&mem->numainfo_updating, 0); | |
889976db YH |
1542 | } |
1543 | ||
1544 | /* | |
1545 | * Selecting a node where we start reclaim from. Because what we need is just | |
1546 | * reducing usage counter, start from anywhere is O,K. Considering | |
1547 | * memory reclaim from current node, there are pros. and cons. | |
1548 | * | |
1549 | * Freeing memory from current node means freeing memory from a node which | |
1550 | * we'll use or we've used. So, it may make LRU bad. And if several threads | |
1551 | * hit limits, it will see a contention on a node. But freeing from remote | |
1552 | * node means more costs for memory reclaim because of memory latency. | |
1553 | * | |
1554 | * Now, we use round-robin. Better algorithm is welcomed. | |
1555 | */ | |
1556 | int mem_cgroup_select_victim_node(struct mem_cgroup *mem) | |
1557 | { | |
1558 | int node; | |
1559 | ||
1560 | mem_cgroup_may_update_nodemask(mem); | |
1561 | node = mem->last_scanned_node; | |
1562 | ||
1563 | node = next_node(node, mem->scan_nodes); | |
1564 | if (node == MAX_NUMNODES) | |
1565 | node = first_node(mem->scan_nodes); | |
1566 | /* | |
1567 | * We call this when we hit limit, not when pages are added to LRU. | |
1568 | * No LRU may hold pages because all pages are UNEVICTABLE or | |
1569 | * memcg is too small and all pages are not on LRU. In that case, | |
1570 | * we use curret node. | |
1571 | */ | |
1572 | if (unlikely(node == MAX_NUMNODES)) | |
1573 | node = numa_node_id(); | |
1574 | ||
1575 | mem->last_scanned_node = node; | |
1576 | return node; | |
1577 | } | |
1578 | ||
4d0c066d KH |
1579 | /* |
1580 | * Check all nodes whether it contains reclaimable pages or not. | |
1581 | * For quick scan, we make use of scan_nodes. This will allow us to skip | |
1582 | * unused nodes. But scan_nodes is lazily updated and may not cotain | |
1583 | * enough new information. We need to do double check. | |
1584 | */ | |
1585 | bool mem_cgroup_reclaimable(struct mem_cgroup *mem, bool noswap) | |
1586 | { | |
1587 | int nid; | |
1588 | ||
1589 | /* | |
1590 | * quick check...making use of scan_node. | |
1591 | * We can skip unused nodes. | |
1592 | */ | |
1593 | if (!nodes_empty(mem->scan_nodes)) { | |
1594 | for (nid = first_node(mem->scan_nodes); | |
1595 | nid < MAX_NUMNODES; | |
1596 | nid = next_node(nid, mem->scan_nodes)) { | |
1597 | ||
1598 | if (test_mem_cgroup_node_reclaimable(mem, nid, noswap)) | |
1599 | return true; | |
1600 | } | |
1601 | } | |
1602 | /* | |
1603 | * Check rest of nodes. | |
1604 | */ | |
1605 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
1606 | if (node_isset(nid, mem->scan_nodes)) | |
1607 | continue; | |
1608 | if (test_mem_cgroup_node_reclaimable(mem, nid, noswap)) | |
1609 | return true; | |
1610 | } | |
1611 | return false; | |
1612 | } | |
1613 | ||
889976db YH |
1614 | #else |
1615 | int mem_cgroup_select_victim_node(struct mem_cgroup *mem) | |
1616 | { | |
1617 | return 0; | |
1618 | } | |
4d0c066d KH |
1619 | |
1620 | bool mem_cgroup_reclaimable(struct mem_cgroup *mem, bool noswap) | |
1621 | { | |
1622 | return test_mem_cgroup_node_reclaimable(mem, 0, noswap); | |
1623 | } | |
889976db YH |
1624 | #endif |
1625 | ||
04046e1a KH |
1626 | /* |
1627 | * Scan the hierarchy if needed to reclaim memory. We remember the last child | |
1628 | * we reclaimed from, so that we don't end up penalizing one child extensively | |
1629 | * based on its position in the children list. | |
6d61ef40 BS |
1630 | * |
1631 | * root_mem is the original ancestor that we've been reclaim from. | |
04046e1a KH |
1632 | * |
1633 | * We give up and return to the caller when we visit root_mem twice. | |
1634 | * (other groups can be removed while we're walking....) | |
81d39c20 KH |
1635 | * |
1636 | * If shrink==true, for avoiding to free too much, this returns immedieately. | |
6d61ef40 BS |
1637 | */ |
1638 | static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, | |
4e416953 | 1639 | struct zone *zone, |
75822b44 | 1640 | gfp_t gfp_mask, |
0ae5e89c YH |
1641 | unsigned long reclaim_options, |
1642 | unsigned long *total_scanned) | |
6d61ef40 | 1643 | { |
04046e1a KH |
1644 | struct mem_cgroup *victim; |
1645 | int ret, total = 0; | |
1646 | int loop = 0; | |
75822b44 BS |
1647 | bool noswap = reclaim_options & MEM_CGROUP_RECLAIM_NOSWAP; |
1648 | bool shrink = reclaim_options & MEM_CGROUP_RECLAIM_SHRINK; | |
4e416953 | 1649 | bool check_soft = reclaim_options & MEM_CGROUP_RECLAIM_SOFT; |
9d11ea9f | 1650 | unsigned long excess; |
0ae5e89c | 1651 | unsigned long nr_scanned; |
9d11ea9f JW |
1652 | |
1653 | excess = res_counter_soft_limit_excess(&root_mem->res) >> PAGE_SHIFT; | |
04046e1a | 1654 | |
22a668d7 | 1655 | /* If memsw_is_minimum==1, swap-out is of-no-use. */ |
108b6a78 | 1656 | if (!check_soft && !shrink && root_mem->memsw_is_minimum) |
22a668d7 KH |
1657 | noswap = true; |
1658 | ||
4e416953 | 1659 | while (1) { |
04046e1a | 1660 | victim = mem_cgroup_select_victim(root_mem); |
4e416953 | 1661 | if (victim == root_mem) { |
04046e1a | 1662 | loop++; |
fbc29a25 KH |
1663 | /* |
1664 | * We are not draining per cpu cached charges during | |
1665 | * soft limit reclaim because global reclaim doesn't | |
1666 | * care about charges. It tries to free some memory and | |
1667 | * charges will not give any. | |
1668 | */ | |
1669 | if (!check_soft && loop >= 1) | |
26fe6168 | 1670 | drain_all_stock_async(root_mem); |
4e416953 BS |
1671 | if (loop >= 2) { |
1672 | /* | |
1673 | * If we have not been able to reclaim | |
1674 | * anything, it might because there are | |
1675 | * no reclaimable pages under this hierarchy | |
1676 | */ | |
1677 | if (!check_soft || !total) { | |
1678 | css_put(&victim->css); | |
1679 | break; | |
1680 | } | |
1681 | /* | |
25985edc | 1682 | * We want to do more targeted reclaim. |
4e416953 BS |
1683 | * excess >> 2 is not to excessive so as to |
1684 | * reclaim too much, nor too less that we keep | |
1685 | * coming back to reclaim from this cgroup | |
1686 | */ | |
1687 | if (total >= (excess >> 2) || | |
1688 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) { | |
1689 | css_put(&victim->css); | |
1690 | break; | |
1691 | } | |
1692 | } | |
1693 | } | |
4d0c066d | 1694 | if (!mem_cgroup_reclaimable(victim, noswap)) { |
04046e1a KH |
1695 | /* this cgroup's local usage == 0 */ |
1696 | css_put(&victim->css); | |
6d61ef40 BS |
1697 | continue; |
1698 | } | |
04046e1a | 1699 | /* we use swappiness of local cgroup */ |
0ae5e89c | 1700 | if (check_soft) { |
4e416953 | 1701 | ret = mem_cgroup_shrink_node_zone(victim, gfp_mask, |
1f4c025b | 1702 | noswap, zone, &nr_scanned); |
0ae5e89c YH |
1703 | *total_scanned += nr_scanned; |
1704 | } else | |
4e416953 | 1705 | ret = try_to_free_mem_cgroup_pages(victim, gfp_mask, |
1f4c025b | 1706 | noswap); |
04046e1a | 1707 | css_put(&victim->css); |
81d39c20 KH |
1708 | /* |
1709 | * At shrinking usage, we can't check we should stop here or | |
1710 | * reclaim more. It's depends on callers. last_scanned_child | |
1711 | * will work enough for keeping fairness under tree. | |
1712 | */ | |
1713 | if (shrink) | |
1714 | return ret; | |
04046e1a | 1715 | total += ret; |
4e416953 | 1716 | if (check_soft) { |
9d11ea9f | 1717 | if (!res_counter_soft_limit_excess(&root_mem->res)) |
4e416953 | 1718 | return total; |
9d11ea9f | 1719 | } else if (mem_cgroup_margin(root_mem)) |
4fd14ebf | 1720 | return total; |
6d61ef40 | 1721 | } |
04046e1a | 1722 | return total; |
6d61ef40 BS |
1723 | } |
1724 | ||
867578cb KH |
1725 | /* |
1726 | * Check OOM-Killer is already running under our hierarchy. | |
1727 | * If someone is running, return false. | |
1af8efe9 | 1728 | * Has to be called with memcg_oom_lock |
867578cb KH |
1729 | */ |
1730 | static bool mem_cgroup_oom_lock(struct mem_cgroup *mem) | |
1731 | { | |
79dfdacc MH |
1732 | int lock_count = -1; |
1733 | struct mem_cgroup *iter, *failed = NULL; | |
1734 | bool cond = true; | |
a636b327 | 1735 | |
79dfdacc MH |
1736 | for_each_mem_cgroup_tree_cond(iter, mem, cond) { |
1737 | bool locked = iter->oom_lock; | |
1738 | ||
1739 | iter->oom_lock = true; | |
1740 | if (lock_count == -1) | |
1741 | lock_count = iter->oom_lock; | |
1742 | else if (lock_count != locked) { | |
1743 | /* | |
1744 | * this subtree of our hierarchy is already locked | |
1745 | * so we cannot give a lock. | |
1746 | */ | |
1747 | lock_count = 0; | |
1748 | failed = iter; | |
1749 | cond = false; | |
1750 | } | |
7d74b06f | 1751 | } |
867578cb | 1752 | |
79dfdacc MH |
1753 | if (!failed) |
1754 | goto done; | |
1755 | ||
1756 | /* | |
1757 | * OK, we failed to lock the whole subtree so we have to clean up | |
1758 | * what we set up to the failing subtree | |
1759 | */ | |
1760 | cond = true; | |
1761 | for_each_mem_cgroup_tree_cond(iter, mem, cond) { | |
1762 | if (iter == failed) { | |
1763 | cond = false; | |
1764 | continue; | |
1765 | } | |
1766 | iter->oom_lock = false; | |
1767 | } | |
1768 | done: | |
1769 | return lock_count; | |
a636b327 | 1770 | } |
0b7f569e | 1771 | |
79dfdacc | 1772 | /* |
1af8efe9 | 1773 | * Has to be called with memcg_oom_lock |
79dfdacc | 1774 | */ |
7d74b06f | 1775 | static int mem_cgroup_oom_unlock(struct mem_cgroup *mem) |
0b7f569e | 1776 | { |
7d74b06f KH |
1777 | struct mem_cgroup *iter; |
1778 | ||
79dfdacc MH |
1779 | for_each_mem_cgroup_tree(iter, mem) |
1780 | iter->oom_lock = false; | |
1781 | return 0; | |
1782 | } | |
1783 | ||
1784 | static void mem_cgroup_mark_under_oom(struct mem_cgroup *mem) | |
1785 | { | |
1786 | struct mem_cgroup *iter; | |
1787 | ||
1788 | for_each_mem_cgroup_tree(iter, mem) | |
1789 | atomic_inc(&iter->under_oom); | |
1790 | } | |
1791 | ||
1792 | static void mem_cgroup_unmark_under_oom(struct mem_cgroup *mem) | |
1793 | { | |
1794 | struct mem_cgroup *iter; | |
1795 | ||
867578cb KH |
1796 | /* |
1797 | * When a new child is created while the hierarchy is under oom, | |
1798 | * mem_cgroup_oom_lock() may not be called. We have to use | |
1799 | * atomic_add_unless() here. | |
1800 | */ | |
7d74b06f | 1801 | for_each_mem_cgroup_tree(iter, mem) |
79dfdacc | 1802 | atomic_add_unless(&iter->under_oom, -1, 0); |
0b7f569e KH |
1803 | } |
1804 | ||
1af8efe9 | 1805 | static DEFINE_SPINLOCK(memcg_oom_lock); |
867578cb KH |
1806 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); |
1807 | ||
dc98df5a KH |
1808 | struct oom_wait_info { |
1809 | struct mem_cgroup *mem; | |
1810 | wait_queue_t wait; | |
1811 | }; | |
1812 | ||
1813 | static int memcg_oom_wake_function(wait_queue_t *wait, | |
1814 | unsigned mode, int sync, void *arg) | |
1815 | { | |
1816 | struct mem_cgroup *wake_mem = (struct mem_cgroup *)arg; | |
1817 | struct oom_wait_info *oom_wait_info; | |
1818 | ||
1819 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
1820 | ||
1821 | if (oom_wait_info->mem == wake_mem) | |
1822 | goto wakeup; | |
1823 | /* if no hierarchy, no match */ | |
1824 | if (!oom_wait_info->mem->use_hierarchy || !wake_mem->use_hierarchy) | |
1825 | return 0; | |
1826 | /* | |
1827 | * Both of oom_wait_info->mem and wake_mem are stable under us. | |
1828 | * Then we can use css_is_ancestor without taking care of RCU. | |
1829 | */ | |
1830 | if (!css_is_ancestor(&oom_wait_info->mem->css, &wake_mem->css) && | |
1831 | !css_is_ancestor(&wake_mem->css, &oom_wait_info->mem->css)) | |
1832 | return 0; | |
1833 | ||
1834 | wakeup: | |
1835 | return autoremove_wake_function(wait, mode, sync, arg); | |
1836 | } | |
1837 | ||
1838 | static void memcg_wakeup_oom(struct mem_cgroup *mem) | |
1839 | { | |
1840 | /* for filtering, pass "mem" as argument. */ | |
1841 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, mem); | |
1842 | } | |
1843 | ||
3c11ecf4 KH |
1844 | static void memcg_oom_recover(struct mem_cgroup *mem) |
1845 | { | |
79dfdacc | 1846 | if (mem && atomic_read(&mem->under_oom)) |
3c11ecf4 KH |
1847 | memcg_wakeup_oom(mem); |
1848 | } | |
1849 | ||
867578cb KH |
1850 | /* |
1851 | * try to call OOM killer. returns false if we should exit memory-reclaim loop. | |
1852 | */ | |
1853 | bool mem_cgroup_handle_oom(struct mem_cgroup *mem, gfp_t mask) | |
0b7f569e | 1854 | { |
dc98df5a | 1855 | struct oom_wait_info owait; |
3c11ecf4 | 1856 | bool locked, need_to_kill; |
867578cb | 1857 | |
dc98df5a KH |
1858 | owait.mem = mem; |
1859 | owait.wait.flags = 0; | |
1860 | owait.wait.func = memcg_oom_wake_function; | |
1861 | owait.wait.private = current; | |
1862 | INIT_LIST_HEAD(&owait.wait.task_list); | |
3c11ecf4 | 1863 | need_to_kill = true; |
79dfdacc MH |
1864 | mem_cgroup_mark_under_oom(mem); |
1865 | ||
867578cb | 1866 | /* At first, try to OOM lock hierarchy under mem.*/ |
1af8efe9 | 1867 | spin_lock(&memcg_oom_lock); |
867578cb KH |
1868 | locked = mem_cgroup_oom_lock(mem); |
1869 | /* | |
1870 | * Even if signal_pending(), we can't quit charge() loop without | |
1871 | * accounting. So, UNINTERRUPTIBLE is appropriate. But SIGKILL | |
1872 | * under OOM is always welcomed, use TASK_KILLABLE here. | |
1873 | */ | |
3c11ecf4 KH |
1874 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
1875 | if (!locked || mem->oom_kill_disable) | |
1876 | need_to_kill = false; | |
1877 | if (locked) | |
9490ff27 | 1878 | mem_cgroup_oom_notify(mem); |
1af8efe9 | 1879 | spin_unlock(&memcg_oom_lock); |
867578cb | 1880 | |
3c11ecf4 KH |
1881 | if (need_to_kill) { |
1882 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
867578cb | 1883 | mem_cgroup_out_of_memory(mem, mask); |
3c11ecf4 | 1884 | } else { |
867578cb | 1885 | schedule(); |
dc98df5a | 1886 | finish_wait(&memcg_oom_waitq, &owait.wait); |
867578cb | 1887 | } |
1af8efe9 | 1888 | spin_lock(&memcg_oom_lock); |
79dfdacc MH |
1889 | if (locked) |
1890 | mem_cgroup_oom_unlock(mem); | |
dc98df5a | 1891 | memcg_wakeup_oom(mem); |
1af8efe9 | 1892 | spin_unlock(&memcg_oom_lock); |
867578cb | 1893 | |
79dfdacc MH |
1894 | mem_cgroup_unmark_under_oom(mem); |
1895 | ||
867578cb KH |
1896 | if (test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current)) |
1897 | return false; | |
1898 | /* Give chance to dying process */ | |
1899 | schedule_timeout(1); | |
1900 | return true; | |
0b7f569e KH |
1901 | } |
1902 | ||
d69b042f BS |
1903 | /* |
1904 | * Currently used to update mapped file statistics, but the routine can be | |
1905 | * generalized to update other statistics as well. | |
32047e2a KH |
1906 | * |
1907 | * Notes: Race condition | |
1908 | * | |
1909 | * We usually use page_cgroup_lock() for accessing page_cgroup member but | |
1910 | * it tends to be costly. But considering some conditions, we doesn't need | |
1911 | * to do so _always_. | |
1912 | * | |
1913 | * Considering "charge", lock_page_cgroup() is not required because all | |
1914 | * file-stat operations happen after a page is attached to radix-tree. There | |
1915 | * are no race with "charge". | |
1916 | * | |
1917 | * Considering "uncharge", we know that memcg doesn't clear pc->mem_cgroup | |
1918 | * at "uncharge" intentionally. So, we always see valid pc->mem_cgroup even | |
1919 | * if there are race with "uncharge". Statistics itself is properly handled | |
1920 | * by flags. | |
1921 | * | |
1922 | * Considering "move", this is an only case we see a race. To make the race | |
1923 | * small, we check MEM_CGROUP_ON_MOVE percpu value and detect there are | |
1924 | * possibility of race condition. If there is, we take a lock. | |
d69b042f | 1925 | */ |
26174efd | 1926 | |
2a7106f2 GT |
1927 | void mem_cgroup_update_page_stat(struct page *page, |
1928 | enum mem_cgroup_page_stat_item idx, int val) | |
d69b042f BS |
1929 | { |
1930 | struct mem_cgroup *mem; | |
32047e2a KH |
1931 | struct page_cgroup *pc = lookup_page_cgroup(page); |
1932 | bool need_unlock = false; | |
dbd4ea78 | 1933 | unsigned long uninitialized_var(flags); |
d69b042f | 1934 | |
d69b042f BS |
1935 | if (unlikely(!pc)) |
1936 | return; | |
1937 | ||
32047e2a | 1938 | rcu_read_lock(); |
d69b042f | 1939 | mem = pc->mem_cgroup; |
32047e2a KH |
1940 | if (unlikely(!mem || !PageCgroupUsed(pc))) |
1941 | goto out; | |
1942 | /* pc->mem_cgroup is unstable ? */ | |
ca3e0214 | 1943 | if (unlikely(mem_cgroup_stealed(mem)) || PageTransHuge(page)) { |
32047e2a | 1944 | /* take a lock against to access pc->mem_cgroup */ |
dbd4ea78 | 1945 | move_lock_page_cgroup(pc, &flags); |
32047e2a KH |
1946 | need_unlock = true; |
1947 | mem = pc->mem_cgroup; | |
1948 | if (!mem || !PageCgroupUsed(pc)) | |
1949 | goto out; | |
1950 | } | |
26174efd | 1951 | |
26174efd | 1952 | switch (idx) { |
2a7106f2 | 1953 | case MEMCG_NR_FILE_MAPPED: |
26174efd KH |
1954 | if (val > 0) |
1955 | SetPageCgroupFileMapped(pc); | |
1956 | else if (!page_mapped(page)) | |
0c270f8f | 1957 | ClearPageCgroupFileMapped(pc); |
2a7106f2 | 1958 | idx = MEM_CGROUP_STAT_FILE_MAPPED; |
26174efd KH |
1959 | break; |
1960 | default: | |
1961 | BUG(); | |
8725d541 | 1962 | } |
d69b042f | 1963 | |
2a7106f2 GT |
1964 | this_cpu_add(mem->stat->count[idx], val); |
1965 | ||
32047e2a KH |
1966 | out: |
1967 | if (unlikely(need_unlock)) | |
dbd4ea78 | 1968 | move_unlock_page_cgroup(pc, &flags); |
32047e2a KH |
1969 | rcu_read_unlock(); |
1970 | return; | |
d69b042f | 1971 | } |
2a7106f2 | 1972 | EXPORT_SYMBOL(mem_cgroup_update_page_stat); |
26174efd | 1973 | |
cdec2e42 KH |
1974 | /* |
1975 | * size of first charge trial. "32" comes from vmscan.c's magic value. | |
1976 | * TODO: maybe necessary to use big numbers in big irons. | |
1977 | */ | |
7ec99d62 | 1978 | #define CHARGE_BATCH 32U |
cdec2e42 KH |
1979 | struct memcg_stock_pcp { |
1980 | struct mem_cgroup *cached; /* this never be root cgroup */ | |
11c9ea4e | 1981 | unsigned int nr_pages; |
cdec2e42 | 1982 | struct work_struct work; |
26fe6168 KH |
1983 | unsigned long flags; |
1984 | #define FLUSHING_CACHED_CHARGE (0) | |
cdec2e42 KH |
1985 | }; |
1986 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); | |
26fe6168 | 1987 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 KH |
1988 | |
1989 | /* | |
11c9ea4e | 1990 | * Try to consume stocked charge on this cpu. If success, one page is consumed |
cdec2e42 KH |
1991 | * from local stock and true is returned. If the stock is 0 or charges from a |
1992 | * cgroup which is not current target, returns false. This stock will be | |
1993 | * refilled. | |
1994 | */ | |
1995 | static bool consume_stock(struct mem_cgroup *mem) | |
1996 | { | |
1997 | struct memcg_stock_pcp *stock; | |
1998 | bool ret = true; | |
1999 | ||
2000 | stock = &get_cpu_var(memcg_stock); | |
11c9ea4e JW |
2001 | if (mem == stock->cached && stock->nr_pages) |
2002 | stock->nr_pages--; | |
cdec2e42 KH |
2003 | else /* need to call res_counter_charge */ |
2004 | ret = false; | |
2005 | put_cpu_var(memcg_stock); | |
2006 | return ret; | |
2007 | } | |
2008 | ||
2009 | /* | |
2010 | * Returns stocks cached in percpu to res_counter and reset cached information. | |
2011 | */ | |
2012 | static void drain_stock(struct memcg_stock_pcp *stock) | |
2013 | { | |
2014 | struct mem_cgroup *old = stock->cached; | |
2015 | ||
11c9ea4e JW |
2016 | if (stock->nr_pages) { |
2017 | unsigned long bytes = stock->nr_pages * PAGE_SIZE; | |
2018 | ||
2019 | res_counter_uncharge(&old->res, bytes); | |
cdec2e42 | 2020 | if (do_swap_account) |
11c9ea4e JW |
2021 | res_counter_uncharge(&old->memsw, bytes); |
2022 | stock->nr_pages = 0; | |
cdec2e42 KH |
2023 | } |
2024 | stock->cached = NULL; | |
cdec2e42 KH |
2025 | } |
2026 | ||
2027 | /* | |
2028 | * This must be called under preempt disabled or must be called by | |
2029 | * a thread which is pinned to local cpu. | |
2030 | */ | |
2031 | static void drain_local_stock(struct work_struct *dummy) | |
2032 | { | |
2033 | struct memcg_stock_pcp *stock = &__get_cpu_var(memcg_stock); | |
2034 | drain_stock(stock); | |
26fe6168 | 2035 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
cdec2e42 KH |
2036 | } |
2037 | ||
2038 | /* | |
2039 | * Cache charges(val) which is from res_counter, to local per_cpu area. | |
320cc51d | 2040 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 2041 | */ |
11c9ea4e | 2042 | static void refill_stock(struct mem_cgroup *mem, unsigned int nr_pages) |
cdec2e42 KH |
2043 | { |
2044 | struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock); | |
2045 | ||
2046 | if (stock->cached != mem) { /* reset if necessary */ | |
2047 | drain_stock(stock); | |
2048 | stock->cached = mem; | |
2049 | } | |
11c9ea4e | 2050 | stock->nr_pages += nr_pages; |
cdec2e42 KH |
2051 | put_cpu_var(memcg_stock); |
2052 | } | |
2053 | ||
2054 | /* | |
2055 | * Tries to drain stocked charges in other cpus. This function is asynchronous | |
2056 | * and just put a work per cpu for draining localy on each cpu. Caller can | |
2057 | * expects some charges will be back to res_counter later but cannot wait for | |
2058 | * it. | |
2059 | */ | |
26fe6168 | 2060 | static void drain_all_stock_async(struct mem_cgroup *root_mem) |
cdec2e42 | 2061 | { |
26fe6168 KH |
2062 | int cpu, curcpu; |
2063 | /* | |
2064 | * If someone calls draining, avoid adding more kworker runs. | |
cdec2e42 | 2065 | */ |
26fe6168 | 2066 | if (!mutex_trylock(&percpu_charge_mutex)) |
cdec2e42 KH |
2067 | return; |
2068 | /* Notify other cpus that system-wide "drain" is running */ | |
cdec2e42 | 2069 | get_online_cpus(); |
26fe6168 KH |
2070 | /* |
2071 | * Get a hint for avoiding draining charges on the current cpu, | |
2072 | * which must be exhausted by our charging. It is not required that | |
2073 | * this be a precise check, so we use raw_smp_processor_id() instead of | |
2074 | * getcpu()/putcpu(). | |
2075 | */ | |
2076 | curcpu = raw_smp_processor_id(); | |
cdec2e42 KH |
2077 | for_each_online_cpu(cpu) { |
2078 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
26fe6168 KH |
2079 | struct mem_cgroup *mem; |
2080 | ||
2081 | if (cpu == curcpu) | |
2082 | continue; | |
2083 | ||
2084 | mem = stock->cached; | |
2085 | if (!mem) | |
2086 | continue; | |
2087 | if (mem != root_mem) { | |
2088 | if (!root_mem->use_hierarchy) | |
2089 | continue; | |
2090 | /* check whether "mem" is under tree of "root_mem" */ | |
2091 | if (!css_is_ancestor(&mem->css, &root_mem->css)) | |
2092 | continue; | |
2093 | } | |
2094 | if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) | |
2095 | schedule_work_on(cpu, &stock->work); | |
cdec2e42 KH |
2096 | } |
2097 | put_online_cpus(); | |
26fe6168 | 2098 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2099 | /* We don't wait for flush_work */ |
2100 | } | |
2101 | ||
2102 | /* This is a synchronous drain interface. */ | |
2103 | static void drain_all_stock_sync(void) | |
2104 | { | |
2105 | /* called when force_empty is called */ | |
26fe6168 | 2106 | mutex_lock(&percpu_charge_mutex); |
cdec2e42 | 2107 | schedule_on_each_cpu(drain_local_stock); |
26fe6168 | 2108 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2109 | } |
2110 | ||
711d3d2c KH |
2111 | /* |
2112 | * This function drains percpu counter value from DEAD cpu and | |
2113 | * move it to local cpu. Note that this function can be preempted. | |
2114 | */ | |
2115 | static void mem_cgroup_drain_pcp_counter(struct mem_cgroup *mem, int cpu) | |
2116 | { | |
2117 | int i; | |
2118 | ||
2119 | spin_lock(&mem->pcp_counter_lock); | |
2120 | for (i = 0; i < MEM_CGROUP_STAT_DATA; i++) { | |
7a159cc9 | 2121 | long x = per_cpu(mem->stat->count[i], cpu); |
711d3d2c KH |
2122 | |
2123 | per_cpu(mem->stat->count[i], cpu) = 0; | |
2124 | mem->nocpu_base.count[i] += x; | |
2125 | } | |
e9f8974f JW |
2126 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) { |
2127 | unsigned long x = per_cpu(mem->stat->events[i], cpu); | |
2128 | ||
2129 | per_cpu(mem->stat->events[i], cpu) = 0; | |
2130 | mem->nocpu_base.events[i] += x; | |
2131 | } | |
1489ebad KH |
2132 | /* need to clear ON_MOVE value, works as a kind of lock. */ |
2133 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) = 0; | |
2134 | spin_unlock(&mem->pcp_counter_lock); | |
2135 | } | |
2136 | ||
2137 | static void synchronize_mem_cgroup_on_move(struct mem_cgroup *mem, int cpu) | |
2138 | { | |
2139 | int idx = MEM_CGROUP_ON_MOVE; | |
2140 | ||
2141 | spin_lock(&mem->pcp_counter_lock); | |
2142 | per_cpu(mem->stat->count[idx], cpu) = mem->nocpu_base.count[idx]; | |
711d3d2c KH |
2143 | spin_unlock(&mem->pcp_counter_lock); |
2144 | } | |
2145 | ||
2146 | static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, | |
cdec2e42 KH |
2147 | unsigned long action, |
2148 | void *hcpu) | |
2149 | { | |
2150 | int cpu = (unsigned long)hcpu; | |
2151 | struct memcg_stock_pcp *stock; | |
711d3d2c | 2152 | struct mem_cgroup *iter; |
cdec2e42 | 2153 | |
1489ebad KH |
2154 | if ((action == CPU_ONLINE)) { |
2155 | for_each_mem_cgroup_all(iter) | |
2156 | synchronize_mem_cgroup_on_move(iter, cpu); | |
2157 | return NOTIFY_OK; | |
2158 | } | |
2159 | ||
711d3d2c | 2160 | if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN) |
cdec2e42 | 2161 | return NOTIFY_OK; |
711d3d2c KH |
2162 | |
2163 | for_each_mem_cgroup_all(iter) | |
2164 | mem_cgroup_drain_pcp_counter(iter, cpu); | |
2165 | ||
cdec2e42 KH |
2166 | stock = &per_cpu(memcg_stock, cpu); |
2167 | drain_stock(stock); | |
2168 | return NOTIFY_OK; | |
2169 | } | |
2170 | ||
4b534334 KH |
2171 | |
2172 | /* See __mem_cgroup_try_charge() for details */ | |
2173 | enum { | |
2174 | CHARGE_OK, /* success */ | |
2175 | CHARGE_RETRY, /* need to retry but retry is not bad */ | |
2176 | CHARGE_NOMEM, /* we can't do more. return -ENOMEM */ | |
2177 | CHARGE_WOULDBLOCK, /* GFP_WAIT wasn't set and no enough res. */ | |
2178 | CHARGE_OOM_DIE, /* the current is killed because of OOM */ | |
2179 | }; | |
2180 | ||
7ec99d62 JW |
2181 | static int mem_cgroup_do_charge(struct mem_cgroup *mem, gfp_t gfp_mask, |
2182 | unsigned int nr_pages, bool oom_check) | |
4b534334 | 2183 | { |
7ec99d62 | 2184 | unsigned long csize = nr_pages * PAGE_SIZE; |
4b534334 KH |
2185 | struct mem_cgroup *mem_over_limit; |
2186 | struct res_counter *fail_res; | |
2187 | unsigned long flags = 0; | |
2188 | int ret; | |
2189 | ||
2190 | ret = res_counter_charge(&mem->res, csize, &fail_res); | |
2191 | ||
2192 | if (likely(!ret)) { | |
2193 | if (!do_swap_account) | |
2194 | return CHARGE_OK; | |
2195 | ret = res_counter_charge(&mem->memsw, csize, &fail_res); | |
2196 | if (likely(!ret)) | |
2197 | return CHARGE_OK; | |
2198 | ||
01c88e2d | 2199 | res_counter_uncharge(&mem->res, csize); |
4b534334 KH |
2200 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw); |
2201 | flags |= MEM_CGROUP_RECLAIM_NOSWAP; | |
2202 | } else | |
2203 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, res); | |
9221edb7 | 2204 | /* |
7ec99d62 JW |
2205 | * nr_pages can be either a huge page (HPAGE_PMD_NR), a batch |
2206 | * of regular pages (CHARGE_BATCH), or a single regular page (1). | |
9221edb7 JW |
2207 | * |
2208 | * Never reclaim on behalf of optional batching, retry with a | |
2209 | * single page instead. | |
2210 | */ | |
7ec99d62 | 2211 | if (nr_pages == CHARGE_BATCH) |
4b534334 KH |
2212 | return CHARGE_RETRY; |
2213 | ||
2214 | if (!(gfp_mask & __GFP_WAIT)) | |
2215 | return CHARGE_WOULDBLOCK; | |
2216 | ||
2217 | ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, NULL, | |
0ae5e89c | 2218 | gfp_mask, flags, NULL); |
7ec99d62 | 2219 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
19942822 | 2220 | return CHARGE_RETRY; |
4b534334 | 2221 | /* |
19942822 JW |
2222 | * Even though the limit is exceeded at this point, reclaim |
2223 | * may have been able to free some pages. Retry the charge | |
2224 | * before killing the task. | |
2225 | * | |
2226 | * Only for regular pages, though: huge pages are rather | |
2227 | * unlikely to succeed so close to the limit, and we fall back | |
2228 | * to regular pages anyway in case of failure. | |
4b534334 | 2229 | */ |
7ec99d62 | 2230 | if (nr_pages == 1 && ret) |
4b534334 KH |
2231 | return CHARGE_RETRY; |
2232 | ||
2233 | /* | |
2234 | * At task move, charge accounts can be doubly counted. So, it's | |
2235 | * better to wait until the end of task_move if something is going on. | |
2236 | */ | |
2237 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2238 | return CHARGE_RETRY; | |
2239 | ||
2240 | /* If we don't need to call oom-killer at el, return immediately */ | |
2241 | if (!oom_check) | |
2242 | return CHARGE_NOMEM; | |
2243 | /* check OOM */ | |
2244 | if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask)) | |
2245 | return CHARGE_OOM_DIE; | |
2246 | ||
2247 | return CHARGE_RETRY; | |
2248 | } | |
2249 | ||
f817ed48 KH |
2250 | /* |
2251 | * Unlike exported interface, "oom" parameter is added. if oom==true, | |
2252 | * oom-killer can be invoked. | |
8a9f3ccd | 2253 | */ |
f817ed48 | 2254 | static int __mem_cgroup_try_charge(struct mm_struct *mm, |
ec168510 | 2255 | gfp_t gfp_mask, |
7ec99d62 JW |
2256 | unsigned int nr_pages, |
2257 | struct mem_cgroup **memcg, | |
2258 | bool oom) | |
8a9f3ccd | 2259 | { |
7ec99d62 | 2260 | unsigned int batch = max(CHARGE_BATCH, nr_pages); |
4b534334 KH |
2261 | int nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; |
2262 | struct mem_cgroup *mem = NULL; | |
2263 | int ret; | |
a636b327 | 2264 | |
867578cb KH |
2265 | /* |
2266 | * Unlike gloval-vm's OOM-kill, we're not in memory shortage | |
2267 | * in system level. So, allow to go ahead dying process in addition to | |
2268 | * MEMDIE process. | |
2269 | */ | |
2270 | if (unlikely(test_thread_flag(TIF_MEMDIE) | |
2271 | || fatal_signal_pending(current))) | |
2272 | goto bypass; | |
a636b327 | 2273 | |
8a9f3ccd | 2274 | /* |
3be91277 HD |
2275 | * We always charge the cgroup the mm_struct belongs to. |
2276 | * The mm_struct's mem_cgroup changes on task migration if the | |
8a9f3ccd BS |
2277 | * thread group leader migrates. It's possible that mm is not |
2278 | * set, if so charge the init_mm (happens for pagecache usage). | |
2279 | */ | |
f75ca962 KH |
2280 | if (!*memcg && !mm) |
2281 | goto bypass; | |
2282 | again: | |
2283 | if (*memcg) { /* css should be a valid one */ | |
4b534334 | 2284 | mem = *memcg; |
f75ca962 KH |
2285 | VM_BUG_ON(css_is_removed(&mem->css)); |
2286 | if (mem_cgroup_is_root(mem)) | |
2287 | goto done; | |
7ec99d62 | 2288 | if (nr_pages == 1 && consume_stock(mem)) |
f75ca962 | 2289 | goto done; |
4b534334 KH |
2290 | css_get(&mem->css); |
2291 | } else { | |
f75ca962 | 2292 | struct task_struct *p; |
54595fe2 | 2293 | |
f75ca962 KH |
2294 | rcu_read_lock(); |
2295 | p = rcu_dereference(mm->owner); | |
f75ca962 | 2296 | /* |
ebb76ce1 KH |
2297 | * Because we don't have task_lock(), "p" can exit. |
2298 | * In that case, "mem" can point to root or p can be NULL with | |
2299 | * race with swapoff. Then, we have small risk of mis-accouning. | |
2300 | * But such kind of mis-account by race always happens because | |
2301 | * we don't have cgroup_mutex(). It's overkill and we allo that | |
2302 | * small race, here. | |
2303 | * (*) swapoff at el will charge against mm-struct not against | |
2304 | * task-struct. So, mm->owner can be NULL. | |
f75ca962 KH |
2305 | */ |
2306 | mem = mem_cgroup_from_task(p); | |
ebb76ce1 | 2307 | if (!mem || mem_cgroup_is_root(mem)) { |
f75ca962 KH |
2308 | rcu_read_unlock(); |
2309 | goto done; | |
2310 | } | |
7ec99d62 | 2311 | if (nr_pages == 1 && consume_stock(mem)) { |
f75ca962 KH |
2312 | /* |
2313 | * It seems dagerous to access memcg without css_get(). | |
2314 | * But considering how consume_stok works, it's not | |
2315 | * necessary. If consume_stock success, some charges | |
2316 | * from this memcg are cached on this cpu. So, we | |
2317 | * don't need to call css_get()/css_tryget() before | |
2318 | * calling consume_stock(). | |
2319 | */ | |
2320 | rcu_read_unlock(); | |
2321 | goto done; | |
2322 | } | |
2323 | /* after here, we may be blocked. we need to get refcnt */ | |
2324 | if (!css_tryget(&mem->css)) { | |
2325 | rcu_read_unlock(); | |
2326 | goto again; | |
2327 | } | |
2328 | rcu_read_unlock(); | |
2329 | } | |
8a9f3ccd | 2330 | |
4b534334 KH |
2331 | do { |
2332 | bool oom_check; | |
7a81b88c | 2333 | |
4b534334 | 2334 | /* If killed, bypass charge */ |
f75ca962 KH |
2335 | if (fatal_signal_pending(current)) { |
2336 | css_put(&mem->css); | |
4b534334 | 2337 | goto bypass; |
f75ca962 | 2338 | } |
6d61ef40 | 2339 | |
4b534334 KH |
2340 | oom_check = false; |
2341 | if (oom && !nr_oom_retries) { | |
2342 | oom_check = true; | |
2343 | nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
cdec2e42 | 2344 | } |
66e1707b | 2345 | |
7ec99d62 | 2346 | ret = mem_cgroup_do_charge(mem, gfp_mask, batch, oom_check); |
4b534334 KH |
2347 | switch (ret) { |
2348 | case CHARGE_OK: | |
2349 | break; | |
2350 | case CHARGE_RETRY: /* not in OOM situation but retry */ | |
7ec99d62 | 2351 | batch = nr_pages; |
f75ca962 KH |
2352 | css_put(&mem->css); |
2353 | mem = NULL; | |
2354 | goto again; | |
4b534334 | 2355 | case CHARGE_WOULDBLOCK: /* !__GFP_WAIT */ |
f75ca962 | 2356 | css_put(&mem->css); |
4b534334 KH |
2357 | goto nomem; |
2358 | case CHARGE_NOMEM: /* OOM routine works */ | |
f75ca962 KH |
2359 | if (!oom) { |
2360 | css_put(&mem->css); | |
867578cb | 2361 | goto nomem; |
f75ca962 | 2362 | } |
4b534334 KH |
2363 | /* If oom, we never return -ENOMEM */ |
2364 | nr_oom_retries--; | |
2365 | break; | |
2366 | case CHARGE_OOM_DIE: /* Killed by OOM Killer */ | |
f75ca962 | 2367 | css_put(&mem->css); |
867578cb | 2368 | goto bypass; |
66e1707b | 2369 | } |
4b534334 KH |
2370 | } while (ret != CHARGE_OK); |
2371 | ||
7ec99d62 JW |
2372 | if (batch > nr_pages) |
2373 | refill_stock(mem, batch - nr_pages); | |
f75ca962 | 2374 | css_put(&mem->css); |
0c3e73e8 | 2375 | done: |
f75ca962 | 2376 | *memcg = mem; |
7a81b88c KH |
2377 | return 0; |
2378 | nomem: | |
f75ca962 | 2379 | *memcg = NULL; |
7a81b88c | 2380 | return -ENOMEM; |
867578cb KH |
2381 | bypass: |
2382 | *memcg = NULL; | |
2383 | return 0; | |
7a81b88c | 2384 | } |
8a9f3ccd | 2385 | |
a3032a2c DN |
2386 | /* |
2387 | * Somemtimes we have to undo a charge we got by try_charge(). | |
2388 | * This function is for that and do uncharge, put css's refcnt. | |
2389 | * gotten by try_charge(). | |
2390 | */ | |
854ffa8d | 2391 | static void __mem_cgroup_cancel_charge(struct mem_cgroup *mem, |
e7018b8d | 2392 | unsigned int nr_pages) |
a3032a2c DN |
2393 | { |
2394 | if (!mem_cgroup_is_root(mem)) { | |
e7018b8d JW |
2395 | unsigned long bytes = nr_pages * PAGE_SIZE; |
2396 | ||
2397 | res_counter_uncharge(&mem->res, bytes); | |
a3032a2c | 2398 | if (do_swap_account) |
e7018b8d | 2399 | res_counter_uncharge(&mem->memsw, bytes); |
a3032a2c | 2400 | } |
854ffa8d DN |
2401 | } |
2402 | ||
a3b2d692 KH |
2403 | /* |
2404 | * A helper function to get mem_cgroup from ID. must be called under | |
2405 | * rcu_read_lock(). The caller must check css_is_removed() or some if | |
2406 | * it's concern. (dropping refcnt from swap can be called against removed | |
2407 | * memcg.) | |
2408 | */ | |
2409 | static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) | |
2410 | { | |
2411 | struct cgroup_subsys_state *css; | |
2412 | ||
2413 | /* ID 0 is unused ID */ | |
2414 | if (!id) | |
2415 | return NULL; | |
2416 | css = css_lookup(&mem_cgroup_subsys, id); | |
2417 | if (!css) | |
2418 | return NULL; | |
2419 | return container_of(css, struct mem_cgroup, css); | |
2420 | } | |
2421 | ||
e42d9d5d | 2422 | struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) |
b5a84319 | 2423 | { |
e42d9d5d | 2424 | struct mem_cgroup *mem = NULL; |
3c776e64 | 2425 | struct page_cgroup *pc; |
a3b2d692 | 2426 | unsigned short id; |
b5a84319 KH |
2427 | swp_entry_t ent; |
2428 | ||
3c776e64 DN |
2429 | VM_BUG_ON(!PageLocked(page)); |
2430 | ||
3c776e64 | 2431 | pc = lookup_page_cgroup(page); |
c0bd3f63 | 2432 | lock_page_cgroup(pc); |
a3b2d692 | 2433 | if (PageCgroupUsed(pc)) { |
3c776e64 | 2434 | mem = pc->mem_cgroup; |
a3b2d692 KH |
2435 | if (mem && !css_tryget(&mem->css)) |
2436 | mem = NULL; | |
e42d9d5d | 2437 | } else if (PageSwapCache(page)) { |
3c776e64 | 2438 | ent.val = page_private(page); |
a3b2d692 KH |
2439 | id = lookup_swap_cgroup(ent); |
2440 | rcu_read_lock(); | |
2441 | mem = mem_cgroup_lookup(id); | |
2442 | if (mem && !css_tryget(&mem->css)) | |
2443 | mem = NULL; | |
2444 | rcu_read_unlock(); | |
3c776e64 | 2445 | } |
c0bd3f63 | 2446 | unlock_page_cgroup(pc); |
b5a84319 KH |
2447 | return mem; |
2448 | } | |
2449 | ||
ca3e0214 | 2450 | static void __mem_cgroup_commit_charge(struct mem_cgroup *mem, |
5564e88b | 2451 | struct page *page, |
7ec99d62 | 2452 | unsigned int nr_pages, |
ca3e0214 | 2453 | struct page_cgroup *pc, |
7ec99d62 | 2454 | enum charge_type ctype) |
7a81b88c | 2455 | { |
ca3e0214 KH |
2456 | lock_page_cgroup(pc); |
2457 | if (unlikely(PageCgroupUsed(pc))) { | |
2458 | unlock_page_cgroup(pc); | |
e7018b8d | 2459 | __mem_cgroup_cancel_charge(mem, nr_pages); |
ca3e0214 KH |
2460 | return; |
2461 | } | |
2462 | /* | |
2463 | * we don't need page_cgroup_lock about tail pages, becase they are not | |
2464 | * accessed by any other context at this point. | |
2465 | */ | |
8a9f3ccd | 2466 | pc->mem_cgroup = mem; |
261fb61a KH |
2467 | /* |
2468 | * We access a page_cgroup asynchronously without lock_page_cgroup(). | |
2469 | * Especially when a page_cgroup is taken from a page, pc->mem_cgroup | |
2470 | * is accessed after testing USED bit. To make pc->mem_cgroup visible | |
2471 | * before USED bit, we need memory barrier here. | |
2472 | * See mem_cgroup_add_lru_list(), etc. | |
2473 | */ | |
08e552c6 | 2474 | smp_wmb(); |
4b3bde4c BS |
2475 | switch (ctype) { |
2476 | case MEM_CGROUP_CHARGE_TYPE_CACHE: | |
2477 | case MEM_CGROUP_CHARGE_TYPE_SHMEM: | |
2478 | SetPageCgroupCache(pc); | |
2479 | SetPageCgroupUsed(pc); | |
2480 | break; | |
2481 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
2482 | ClearPageCgroupCache(pc); | |
2483 | SetPageCgroupUsed(pc); | |
2484 | break; | |
2485 | default: | |
2486 | break; | |
2487 | } | |
3be91277 | 2488 | |
ca3e0214 | 2489 | mem_cgroup_charge_statistics(mem, PageCgroupCache(pc), nr_pages); |
52d4b9ac | 2490 | unlock_page_cgroup(pc); |
430e4863 KH |
2491 | /* |
2492 | * "charge_statistics" updated event counter. Then, check it. | |
2493 | * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree. | |
2494 | * if they exceeds softlimit. | |
2495 | */ | |
5564e88b | 2496 | memcg_check_events(mem, page); |
7a81b88c | 2497 | } |
66e1707b | 2498 | |
ca3e0214 KH |
2499 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
2500 | ||
2501 | #define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) | (1 << PCG_MOVE_LOCK) |\ | |
2502 | (1 << PCG_ACCT_LRU) | (1 << PCG_MIGRATION)) | |
2503 | /* | |
2504 | * Because tail pages are not marked as "used", set it. We're under | |
2505 | * zone->lru_lock, 'splitting on pmd' and compund_lock. | |
2506 | */ | |
2507 | void mem_cgroup_split_huge_fixup(struct page *head, struct page *tail) | |
2508 | { | |
2509 | struct page_cgroup *head_pc = lookup_page_cgroup(head); | |
2510 | struct page_cgroup *tail_pc = lookup_page_cgroup(tail); | |
2511 | unsigned long flags; | |
2512 | ||
3d37c4a9 KH |
2513 | if (mem_cgroup_disabled()) |
2514 | return; | |
ca3e0214 | 2515 | /* |
ece35ca8 | 2516 | * We have no races with charge/uncharge but will have races with |
ca3e0214 KH |
2517 | * page state accounting. |
2518 | */ | |
2519 | move_lock_page_cgroup(head_pc, &flags); | |
2520 | ||
2521 | tail_pc->mem_cgroup = head_pc->mem_cgroup; | |
2522 | smp_wmb(); /* see __commit_charge() */ | |
ece35ca8 KH |
2523 | if (PageCgroupAcctLRU(head_pc)) { |
2524 | enum lru_list lru; | |
2525 | struct mem_cgroup_per_zone *mz; | |
2526 | ||
2527 | /* | |
2528 | * LRU flags cannot be copied because we need to add tail | |
2529 | *.page to LRU by generic call and our hook will be called. | |
2530 | * We hold lru_lock, then, reduce counter directly. | |
2531 | */ | |
2532 | lru = page_lru(head); | |
97a6c37b | 2533 | mz = page_cgroup_zoneinfo(head_pc->mem_cgroup, head); |
ece35ca8 KH |
2534 | MEM_CGROUP_ZSTAT(mz, lru) -= 1; |
2535 | } | |
ca3e0214 KH |
2536 | tail_pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT; |
2537 | move_unlock_page_cgroup(head_pc, &flags); | |
2538 | } | |
2539 | #endif | |
2540 | ||
f817ed48 | 2541 | /** |
de3638d9 | 2542 | * mem_cgroup_move_account - move account of the page |
5564e88b | 2543 | * @page: the page |
7ec99d62 | 2544 | * @nr_pages: number of regular pages (>1 for huge pages) |
f817ed48 KH |
2545 | * @pc: page_cgroup of the page. |
2546 | * @from: mem_cgroup which the page is moved from. | |
2547 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
854ffa8d | 2548 | * @uncharge: whether we should call uncharge and css_put against @from. |
f817ed48 KH |
2549 | * |
2550 | * The caller must confirm following. | |
08e552c6 | 2551 | * - page is not on LRU (isolate_page() is useful.) |
7ec99d62 | 2552 | * - compound_lock is held when nr_pages > 1 |
f817ed48 | 2553 | * |
854ffa8d | 2554 | * This function doesn't do "charge" nor css_get to new cgroup. It should be |
25985edc | 2555 | * done by a caller(__mem_cgroup_try_charge would be useful). If @uncharge is |
854ffa8d DN |
2556 | * true, this function does "uncharge" from old cgroup, but it doesn't if |
2557 | * @uncharge is false, so a caller should do "uncharge". | |
f817ed48 | 2558 | */ |
7ec99d62 JW |
2559 | static int mem_cgroup_move_account(struct page *page, |
2560 | unsigned int nr_pages, | |
2561 | struct page_cgroup *pc, | |
2562 | struct mem_cgroup *from, | |
2563 | struct mem_cgroup *to, | |
2564 | bool uncharge) | |
f817ed48 | 2565 | { |
de3638d9 JW |
2566 | unsigned long flags; |
2567 | int ret; | |
987eba66 | 2568 | |
f817ed48 | 2569 | VM_BUG_ON(from == to); |
5564e88b | 2570 | VM_BUG_ON(PageLRU(page)); |
de3638d9 JW |
2571 | /* |
2572 | * The page is isolated from LRU. So, collapse function | |
2573 | * will not handle this page. But page splitting can happen. | |
2574 | * Do this check under compound_page_lock(). The caller should | |
2575 | * hold it. | |
2576 | */ | |
2577 | ret = -EBUSY; | |
7ec99d62 | 2578 | if (nr_pages > 1 && !PageTransHuge(page)) |
de3638d9 JW |
2579 | goto out; |
2580 | ||
2581 | lock_page_cgroup(pc); | |
2582 | ||
2583 | ret = -EINVAL; | |
2584 | if (!PageCgroupUsed(pc) || pc->mem_cgroup != from) | |
2585 | goto unlock; | |
2586 | ||
2587 | move_lock_page_cgroup(pc, &flags); | |
f817ed48 | 2588 | |
8725d541 | 2589 | if (PageCgroupFileMapped(pc)) { |
c62b1a3b KH |
2590 | /* Update mapped_file data for mem_cgroup */ |
2591 | preempt_disable(); | |
2592 | __this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2593 | __this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2594 | preempt_enable(); | |
d69b042f | 2595 | } |
987eba66 | 2596 | mem_cgroup_charge_statistics(from, PageCgroupCache(pc), -nr_pages); |
854ffa8d DN |
2597 | if (uncharge) |
2598 | /* This is not "cancel", but cancel_charge does all we need. */ | |
e7018b8d | 2599 | __mem_cgroup_cancel_charge(from, nr_pages); |
d69b042f | 2600 | |
854ffa8d | 2601 | /* caller should have done css_get */ |
08e552c6 | 2602 | pc->mem_cgroup = to; |
987eba66 | 2603 | mem_cgroup_charge_statistics(to, PageCgroupCache(pc), nr_pages); |
88703267 KH |
2604 | /* |
2605 | * We charges against "to" which may not have any tasks. Then, "to" | |
2606 | * can be under rmdir(). But in current implementation, caller of | |
4ffef5fe | 2607 | * this function is just force_empty() and move charge, so it's |
25985edc | 2608 | * guaranteed that "to" is never removed. So, we don't check rmdir |
4ffef5fe | 2609 | * status here. |
88703267 | 2610 | */ |
de3638d9 JW |
2611 | move_unlock_page_cgroup(pc, &flags); |
2612 | ret = 0; | |
2613 | unlock: | |
57f9fd7d | 2614 | unlock_page_cgroup(pc); |
d2265e6f KH |
2615 | /* |
2616 | * check events | |
2617 | */ | |
5564e88b JW |
2618 | memcg_check_events(to, page); |
2619 | memcg_check_events(from, page); | |
de3638d9 | 2620 | out: |
f817ed48 KH |
2621 | return ret; |
2622 | } | |
2623 | ||
2624 | /* | |
2625 | * move charges to its parent. | |
2626 | */ | |
2627 | ||
5564e88b JW |
2628 | static int mem_cgroup_move_parent(struct page *page, |
2629 | struct page_cgroup *pc, | |
f817ed48 KH |
2630 | struct mem_cgroup *child, |
2631 | gfp_t gfp_mask) | |
2632 | { | |
2633 | struct cgroup *cg = child->css.cgroup; | |
2634 | struct cgroup *pcg = cg->parent; | |
2635 | struct mem_cgroup *parent; | |
7ec99d62 | 2636 | unsigned int nr_pages; |
4be4489f | 2637 | unsigned long uninitialized_var(flags); |
f817ed48 KH |
2638 | int ret; |
2639 | ||
2640 | /* Is ROOT ? */ | |
2641 | if (!pcg) | |
2642 | return -EINVAL; | |
2643 | ||
57f9fd7d DN |
2644 | ret = -EBUSY; |
2645 | if (!get_page_unless_zero(page)) | |
2646 | goto out; | |
2647 | if (isolate_lru_page(page)) | |
2648 | goto put; | |
52dbb905 | 2649 | |
7ec99d62 | 2650 | nr_pages = hpage_nr_pages(page); |
08e552c6 | 2651 | |
f817ed48 | 2652 | parent = mem_cgroup_from_cont(pcg); |
7ec99d62 | 2653 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, nr_pages, &parent, false); |
a636b327 | 2654 | if (ret || !parent) |
57f9fd7d | 2655 | goto put_back; |
f817ed48 | 2656 | |
7ec99d62 | 2657 | if (nr_pages > 1) |
987eba66 KH |
2658 | flags = compound_lock_irqsave(page); |
2659 | ||
7ec99d62 | 2660 | ret = mem_cgroup_move_account(page, nr_pages, pc, child, parent, true); |
854ffa8d | 2661 | if (ret) |
7ec99d62 | 2662 | __mem_cgroup_cancel_charge(parent, nr_pages); |
8dba474f | 2663 | |
7ec99d62 | 2664 | if (nr_pages > 1) |
987eba66 | 2665 | compound_unlock_irqrestore(page, flags); |
8dba474f | 2666 | put_back: |
08e552c6 | 2667 | putback_lru_page(page); |
57f9fd7d | 2668 | put: |
40d58138 | 2669 | put_page(page); |
57f9fd7d | 2670 | out: |
f817ed48 KH |
2671 | return ret; |
2672 | } | |
2673 | ||
7a81b88c KH |
2674 | /* |
2675 | * Charge the memory controller for page usage. | |
2676 | * Return | |
2677 | * 0 if the charge was successful | |
2678 | * < 0 if the cgroup is over its limit | |
2679 | */ | |
2680 | static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, | |
73045c47 | 2681 | gfp_t gfp_mask, enum charge_type ctype) |
7a81b88c | 2682 | { |
73045c47 | 2683 | struct mem_cgroup *mem = NULL; |
7ec99d62 | 2684 | unsigned int nr_pages = 1; |
7a81b88c | 2685 | struct page_cgroup *pc; |
8493ae43 | 2686 | bool oom = true; |
7a81b88c | 2687 | int ret; |
ec168510 | 2688 | |
37c2ac78 | 2689 | if (PageTransHuge(page)) { |
7ec99d62 | 2690 | nr_pages <<= compound_order(page); |
37c2ac78 | 2691 | VM_BUG_ON(!PageTransHuge(page)); |
8493ae43 JW |
2692 | /* |
2693 | * Never OOM-kill a process for a huge page. The | |
2694 | * fault handler will fall back to regular pages. | |
2695 | */ | |
2696 | oom = false; | |
37c2ac78 | 2697 | } |
7a81b88c KH |
2698 | |
2699 | pc = lookup_page_cgroup(page); | |
af4a6621 | 2700 | BUG_ON(!pc); /* XXX: remove this and move pc lookup into commit */ |
7a81b88c | 2701 | |
7ec99d62 | 2702 | ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &mem, oom); |
a636b327 | 2703 | if (ret || !mem) |
7a81b88c KH |
2704 | return ret; |
2705 | ||
7ec99d62 | 2706 | __mem_cgroup_commit_charge(mem, page, nr_pages, pc, ctype); |
8a9f3ccd | 2707 | return 0; |
8a9f3ccd BS |
2708 | } |
2709 | ||
7a81b88c KH |
2710 | int mem_cgroup_newpage_charge(struct page *page, |
2711 | struct mm_struct *mm, gfp_t gfp_mask) | |
217bc319 | 2712 | { |
f8d66542 | 2713 | if (mem_cgroup_disabled()) |
cede86ac | 2714 | return 0; |
69029cd5 KH |
2715 | /* |
2716 | * If already mapped, we don't have to account. | |
2717 | * If page cache, page->mapping has address_space. | |
2718 | * But page->mapping may have out-of-use anon_vma pointer, | |
2719 | * detecit it by PageAnon() check. newly-mapped-anon's page->mapping | |
2720 | * is NULL. | |
2721 | */ | |
2722 | if (page_mapped(page) || (page->mapping && !PageAnon(page))) | |
2723 | return 0; | |
2724 | if (unlikely(!mm)) | |
2725 | mm = &init_mm; | |
217bc319 | 2726 | return mem_cgroup_charge_common(page, mm, gfp_mask, |
73045c47 | 2727 | MEM_CGROUP_CHARGE_TYPE_MAPPED); |
217bc319 KH |
2728 | } |
2729 | ||
83aae4c7 DN |
2730 | static void |
2731 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
2732 | enum charge_type ctype); | |
2733 | ||
5a6475a4 KH |
2734 | static void |
2735 | __mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *mem, | |
2736 | enum charge_type ctype) | |
2737 | { | |
2738 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
2739 | /* | |
2740 | * In some case, SwapCache, FUSE(splice_buf->radixtree), the page | |
2741 | * is already on LRU. It means the page may on some other page_cgroup's | |
2742 | * LRU. Take care of it. | |
2743 | */ | |
2744 | mem_cgroup_lru_del_before_commit(page); | |
2745 | __mem_cgroup_commit_charge(mem, page, 1, pc, ctype); | |
2746 | mem_cgroup_lru_add_after_commit(page); | |
2747 | return; | |
2748 | } | |
2749 | ||
e1a1cd59 BS |
2750 | int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, |
2751 | gfp_t gfp_mask) | |
8697d331 | 2752 | { |
5a6475a4 | 2753 | struct mem_cgroup *mem = NULL; |
b5a84319 KH |
2754 | int ret; |
2755 | ||
f8d66542 | 2756 | if (mem_cgroup_disabled()) |
cede86ac | 2757 | return 0; |
52d4b9ac KH |
2758 | if (PageCompound(page)) |
2759 | return 0; | |
accf163e KH |
2760 | /* |
2761 | * Corner case handling. This is called from add_to_page_cache() | |
2762 | * in usual. But some FS (shmem) precharges this page before calling it | |
2763 | * and call add_to_page_cache() with GFP_NOWAIT. | |
2764 | * | |
2765 | * For GFP_NOWAIT case, the page may be pre-charged before calling | |
2766 | * add_to_page_cache(). (See shmem.c) check it here and avoid to call | |
2767 | * charge twice. (It works but has to pay a bit larger cost.) | |
b5a84319 KH |
2768 | * And when the page is SwapCache, it should take swap information |
2769 | * into account. This is under lock_page() now. | |
accf163e KH |
2770 | */ |
2771 | if (!(gfp_mask & __GFP_WAIT)) { | |
2772 | struct page_cgroup *pc; | |
2773 | ||
52d4b9ac KH |
2774 | pc = lookup_page_cgroup(page); |
2775 | if (!pc) | |
2776 | return 0; | |
2777 | lock_page_cgroup(pc); | |
2778 | if (PageCgroupUsed(pc)) { | |
2779 | unlock_page_cgroup(pc); | |
accf163e KH |
2780 | return 0; |
2781 | } | |
52d4b9ac | 2782 | unlock_page_cgroup(pc); |
accf163e KH |
2783 | } |
2784 | ||
73045c47 | 2785 | if (unlikely(!mm)) |
8697d331 | 2786 | mm = &init_mm; |
accf163e | 2787 | |
5a6475a4 KH |
2788 | if (page_is_file_cache(page)) { |
2789 | ret = __mem_cgroup_try_charge(mm, gfp_mask, 1, &mem, true); | |
2790 | if (ret || !mem) | |
2791 | return ret; | |
b5a84319 | 2792 | |
5a6475a4 KH |
2793 | /* |
2794 | * FUSE reuses pages without going through the final | |
2795 | * put that would remove them from the LRU list, make | |
2796 | * sure that they get relinked properly. | |
2797 | */ | |
2798 | __mem_cgroup_commit_charge_lrucare(page, mem, | |
2799 | MEM_CGROUP_CHARGE_TYPE_CACHE); | |
2800 | return ret; | |
2801 | } | |
83aae4c7 DN |
2802 | /* shmem */ |
2803 | if (PageSwapCache(page)) { | |
2804 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); | |
2805 | if (!ret) | |
2806 | __mem_cgroup_commit_charge_swapin(page, mem, | |
2807 | MEM_CGROUP_CHARGE_TYPE_SHMEM); | |
2808 | } else | |
2809 | ret = mem_cgroup_charge_common(page, mm, gfp_mask, | |
73045c47 | 2810 | MEM_CGROUP_CHARGE_TYPE_SHMEM); |
b5a84319 | 2811 | |
b5a84319 | 2812 | return ret; |
e8589cc1 KH |
2813 | } |
2814 | ||
54595fe2 KH |
2815 | /* |
2816 | * While swap-in, try_charge -> commit or cancel, the page is locked. | |
2817 | * And when try_charge() successfully returns, one refcnt to memcg without | |
21ae2956 | 2818 | * struct page_cgroup is acquired. This refcnt will be consumed by |
54595fe2 KH |
2819 | * "commit()" or removed by "cancel()" |
2820 | */ | |
8c7c6e34 KH |
2821 | int mem_cgroup_try_charge_swapin(struct mm_struct *mm, |
2822 | struct page *page, | |
2823 | gfp_t mask, struct mem_cgroup **ptr) | |
2824 | { | |
2825 | struct mem_cgroup *mem; | |
54595fe2 | 2826 | int ret; |
8c7c6e34 | 2827 | |
56039efa KH |
2828 | *ptr = NULL; |
2829 | ||
f8d66542 | 2830 | if (mem_cgroup_disabled()) |
8c7c6e34 KH |
2831 | return 0; |
2832 | ||
2833 | if (!do_swap_account) | |
2834 | goto charge_cur_mm; | |
8c7c6e34 KH |
2835 | /* |
2836 | * A racing thread's fault, or swapoff, may have already updated | |
407f9c8b HD |
2837 | * the pte, and even removed page from swap cache: in those cases |
2838 | * do_swap_page()'s pte_same() test will fail; but there's also a | |
2839 | * KSM case which does need to charge the page. | |
8c7c6e34 KH |
2840 | */ |
2841 | if (!PageSwapCache(page)) | |
407f9c8b | 2842 | goto charge_cur_mm; |
e42d9d5d | 2843 | mem = try_get_mem_cgroup_from_page(page); |
54595fe2 KH |
2844 | if (!mem) |
2845 | goto charge_cur_mm; | |
8c7c6e34 | 2846 | *ptr = mem; |
7ec99d62 | 2847 | ret = __mem_cgroup_try_charge(NULL, mask, 1, ptr, true); |
54595fe2 KH |
2848 | css_put(&mem->css); |
2849 | return ret; | |
8c7c6e34 KH |
2850 | charge_cur_mm: |
2851 | if (unlikely(!mm)) | |
2852 | mm = &init_mm; | |
7ec99d62 | 2853 | return __mem_cgroup_try_charge(mm, mask, 1, ptr, true); |
8c7c6e34 KH |
2854 | } |
2855 | ||
83aae4c7 DN |
2856 | static void |
2857 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
2858 | enum charge_type ctype) | |
7a81b88c | 2859 | { |
f8d66542 | 2860 | if (mem_cgroup_disabled()) |
7a81b88c KH |
2861 | return; |
2862 | if (!ptr) | |
2863 | return; | |
88703267 | 2864 | cgroup_exclude_rmdir(&ptr->css); |
5a6475a4 KH |
2865 | |
2866 | __mem_cgroup_commit_charge_lrucare(page, ptr, ctype); | |
8c7c6e34 KH |
2867 | /* |
2868 | * Now swap is on-memory. This means this page may be | |
2869 | * counted both as mem and swap....double count. | |
03f3c433 KH |
2870 | * Fix it by uncharging from memsw. Basically, this SwapCache is stable |
2871 | * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page() | |
2872 | * may call delete_from_swap_cache() before reach here. | |
8c7c6e34 | 2873 | */ |
03f3c433 | 2874 | if (do_swap_account && PageSwapCache(page)) { |
8c7c6e34 | 2875 | swp_entry_t ent = {.val = page_private(page)}; |
a3b2d692 | 2876 | unsigned short id; |
8c7c6e34 | 2877 | struct mem_cgroup *memcg; |
a3b2d692 KH |
2878 | |
2879 | id = swap_cgroup_record(ent, 0); | |
2880 | rcu_read_lock(); | |
2881 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 2882 | if (memcg) { |
a3b2d692 KH |
2883 | /* |
2884 | * This recorded memcg can be obsolete one. So, avoid | |
2885 | * calling css_tryget | |
2886 | */ | |
0c3e73e8 | 2887 | if (!mem_cgroup_is_root(memcg)) |
4e649152 | 2888 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
0c3e73e8 | 2889 | mem_cgroup_swap_statistics(memcg, false); |
8c7c6e34 KH |
2890 | mem_cgroup_put(memcg); |
2891 | } | |
a3b2d692 | 2892 | rcu_read_unlock(); |
8c7c6e34 | 2893 | } |
88703267 KH |
2894 | /* |
2895 | * At swapin, we may charge account against cgroup which has no tasks. | |
2896 | * So, rmdir()->pre_destroy() can be called while we do this charge. | |
2897 | * In that case, we need to call pre_destroy() again. check it here. | |
2898 | */ | |
2899 | cgroup_release_and_wakeup_rmdir(&ptr->css); | |
7a81b88c KH |
2900 | } |
2901 | ||
83aae4c7 DN |
2902 | void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) |
2903 | { | |
2904 | __mem_cgroup_commit_charge_swapin(page, ptr, | |
2905 | MEM_CGROUP_CHARGE_TYPE_MAPPED); | |
2906 | } | |
2907 | ||
7a81b88c KH |
2908 | void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem) |
2909 | { | |
f8d66542 | 2910 | if (mem_cgroup_disabled()) |
7a81b88c KH |
2911 | return; |
2912 | if (!mem) | |
2913 | return; | |
e7018b8d | 2914 | __mem_cgroup_cancel_charge(mem, 1); |
7a81b88c KH |
2915 | } |
2916 | ||
7ec99d62 JW |
2917 | static void mem_cgroup_do_uncharge(struct mem_cgroup *mem, |
2918 | unsigned int nr_pages, | |
2919 | const enum charge_type ctype) | |
569b846d KH |
2920 | { |
2921 | struct memcg_batch_info *batch = NULL; | |
2922 | bool uncharge_memsw = true; | |
7ec99d62 | 2923 | |
569b846d KH |
2924 | /* If swapout, usage of swap doesn't decrease */ |
2925 | if (!do_swap_account || ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) | |
2926 | uncharge_memsw = false; | |
569b846d KH |
2927 | |
2928 | batch = ¤t->memcg_batch; | |
2929 | /* | |
2930 | * In usual, we do css_get() when we remember memcg pointer. | |
2931 | * But in this case, we keep res->usage until end of a series of | |
2932 | * uncharges. Then, it's ok to ignore memcg's refcnt. | |
2933 | */ | |
2934 | if (!batch->memcg) | |
2935 | batch->memcg = mem; | |
3c11ecf4 KH |
2936 | /* |
2937 | * do_batch > 0 when unmapping pages or inode invalidate/truncate. | |
25985edc | 2938 | * In those cases, all pages freed continuously can be expected to be in |
3c11ecf4 KH |
2939 | * the same cgroup and we have chance to coalesce uncharges. |
2940 | * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE) | |
2941 | * because we want to do uncharge as soon as possible. | |
2942 | */ | |
2943 | ||
2944 | if (!batch->do_batch || test_thread_flag(TIF_MEMDIE)) | |
2945 | goto direct_uncharge; | |
2946 | ||
7ec99d62 | 2947 | if (nr_pages > 1) |
ec168510 AA |
2948 | goto direct_uncharge; |
2949 | ||
569b846d KH |
2950 | /* |
2951 | * In typical case, batch->memcg == mem. This means we can | |
2952 | * merge a series of uncharges to an uncharge of res_counter. | |
2953 | * If not, we uncharge res_counter ony by one. | |
2954 | */ | |
2955 | if (batch->memcg != mem) | |
2956 | goto direct_uncharge; | |
2957 | /* remember freed charge and uncharge it later */ | |
7ffd4ca7 | 2958 | batch->nr_pages++; |
569b846d | 2959 | if (uncharge_memsw) |
7ffd4ca7 | 2960 | batch->memsw_nr_pages++; |
569b846d KH |
2961 | return; |
2962 | direct_uncharge: | |
7ec99d62 | 2963 | res_counter_uncharge(&mem->res, nr_pages * PAGE_SIZE); |
569b846d | 2964 | if (uncharge_memsw) |
7ec99d62 | 2965 | res_counter_uncharge(&mem->memsw, nr_pages * PAGE_SIZE); |
3c11ecf4 KH |
2966 | if (unlikely(batch->memcg != mem)) |
2967 | memcg_oom_recover(mem); | |
569b846d KH |
2968 | return; |
2969 | } | |
7a81b88c | 2970 | |
8a9f3ccd | 2971 | /* |
69029cd5 | 2972 | * uncharge if !page_mapped(page) |
8a9f3ccd | 2973 | */ |
8c7c6e34 | 2974 | static struct mem_cgroup * |
69029cd5 | 2975 | __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) |
8a9f3ccd | 2976 | { |
8c7c6e34 | 2977 | struct mem_cgroup *mem = NULL; |
7ec99d62 JW |
2978 | unsigned int nr_pages = 1; |
2979 | struct page_cgroup *pc; | |
8a9f3ccd | 2980 | |
f8d66542 | 2981 | if (mem_cgroup_disabled()) |
8c7c6e34 | 2982 | return NULL; |
4077960e | 2983 | |
d13d1443 | 2984 | if (PageSwapCache(page)) |
8c7c6e34 | 2985 | return NULL; |
d13d1443 | 2986 | |
37c2ac78 | 2987 | if (PageTransHuge(page)) { |
7ec99d62 | 2988 | nr_pages <<= compound_order(page); |
37c2ac78 AA |
2989 | VM_BUG_ON(!PageTransHuge(page)); |
2990 | } | |
8697d331 | 2991 | /* |
3c541e14 | 2992 | * Check if our page_cgroup is valid |
8697d331 | 2993 | */ |
52d4b9ac KH |
2994 | pc = lookup_page_cgroup(page); |
2995 | if (unlikely(!pc || !PageCgroupUsed(pc))) | |
8c7c6e34 | 2996 | return NULL; |
b9c565d5 | 2997 | |
52d4b9ac | 2998 | lock_page_cgroup(pc); |
d13d1443 | 2999 | |
8c7c6e34 KH |
3000 | mem = pc->mem_cgroup; |
3001 | ||
d13d1443 KH |
3002 | if (!PageCgroupUsed(pc)) |
3003 | goto unlock_out; | |
3004 | ||
3005 | switch (ctype) { | |
3006 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
8a9478ca | 3007 | case MEM_CGROUP_CHARGE_TYPE_DROP: |
ac39cf8c | 3008 | /* See mem_cgroup_prepare_migration() */ |
3009 | if (page_mapped(page) || PageCgroupMigration(pc)) | |
d13d1443 KH |
3010 | goto unlock_out; |
3011 | break; | |
3012 | case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: | |
3013 | if (!PageAnon(page)) { /* Shared memory */ | |
3014 | if (page->mapping && !page_is_file_cache(page)) | |
3015 | goto unlock_out; | |
3016 | } else if (page_mapped(page)) /* Anon */ | |
3017 | goto unlock_out; | |
3018 | break; | |
3019 | default: | |
3020 | break; | |
52d4b9ac | 3021 | } |
d13d1443 | 3022 | |
7ec99d62 | 3023 | mem_cgroup_charge_statistics(mem, PageCgroupCache(pc), -nr_pages); |
04046e1a | 3024 | |
52d4b9ac | 3025 | ClearPageCgroupUsed(pc); |
544122e5 KH |
3026 | /* |
3027 | * pc->mem_cgroup is not cleared here. It will be accessed when it's | |
3028 | * freed from LRU. This is safe because uncharged page is expected not | |
3029 | * to be reused (freed soon). Exception is SwapCache, it's handled by | |
3030 | * special functions. | |
3031 | */ | |
b9c565d5 | 3032 | |
52d4b9ac | 3033 | unlock_page_cgroup(pc); |
f75ca962 KH |
3034 | /* |
3035 | * even after unlock, we have mem->res.usage here and this memcg | |
3036 | * will never be freed. | |
3037 | */ | |
d2265e6f | 3038 | memcg_check_events(mem, page); |
f75ca962 KH |
3039 | if (do_swap_account && ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) { |
3040 | mem_cgroup_swap_statistics(mem, true); | |
3041 | mem_cgroup_get(mem); | |
3042 | } | |
3043 | if (!mem_cgroup_is_root(mem)) | |
7ec99d62 | 3044 | mem_cgroup_do_uncharge(mem, nr_pages, ctype); |
6d12e2d8 | 3045 | |
8c7c6e34 | 3046 | return mem; |
d13d1443 KH |
3047 | |
3048 | unlock_out: | |
3049 | unlock_page_cgroup(pc); | |
8c7c6e34 | 3050 | return NULL; |
3c541e14 BS |
3051 | } |
3052 | ||
69029cd5 KH |
3053 | void mem_cgroup_uncharge_page(struct page *page) |
3054 | { | |
52d4b9ac KH |
3055 | /* early check. */ |
3056 | if (page_mapped(page)) | |
3057 | return; | |
3058 | if (page->mapping && !PageAnon(page)) | |
3059 | return; | |
69029cd5 KH |
3060 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED); |
3061 | } | |
3062 | ||
3063 | void mem_cgroup_uncharge_cache_page(struct page *page) | |
3064 | { | |
3065 | VM_BUG_ON(page_mapped(page)); | |
b7abea96 | 3066 | VM_BUG_ON(page->mapping); |
69029cd5 KH |
3067 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); |
3068 | } | |
3069 | ||
569b846d KH |
3070 | /* |
3071 | * Batch_start/batch_end is called in unmap_page_range/invlidate/trucate. | |
3072 | * In that cases, pages are freed continuously and we can expect pages | |
3073 | * are in the same memcg. All these calls itself limits the number of | |
3074 | * pages freed at once, then uncharge_start/end() is called properly. | |
3075 | * This may be called prural(2) times in a context, | |
3076 | */ | |
3077 | ||
3078 | void mem_cgroup_uncharge_start(void) | |
3079 | { | |
3080 | current->memcg_batch.do_batch++; | |
3081 | /* We can do nest. */ | |
3082 | if (current->memcg_batch.do_batch == 1) { | |
3083 | current->memcg_batch.memcg = NULL; | |
7ffd4ca7 JW |
3084 | current->memcg_batch.nr_pages = 0; |
3085 | current->memcg_batch.memsw_nr_pages = 0; | |
569b846d KH |
3086 | } |
3087 | } | |
3088 | ||
3089 | void mem_cgroup_uncharge_end(void) | |
3090 | { | |
3091 | struct memcg_batch_info *batch = ¤t->memcg_batch; | |
3092 | ||
3093 | if (!batch->do_batch) | |
3094 | return; | |
3095 | ||
3096 | batch->do_batch--; | |
3097 | if (batch->do_batch) /* If stacked, do nothing. */ | |
3098 | return; | |
3099 | ||
3100 | if (!batch->memcg) | |
3101 | return; | |
3102 | /* | |
3103 | * This "batch->memcg" is valid without any css_get/put etc... | |
3104 | * bacause we hide charges behind us. | |
3105 | */ | |
7ffd4ca7 JW |
3106 | if (batch->nr_pages) |
3107 | res_counter_uncharge(&batch->memcg->res, | |
3108 | batch->nr_pages * PAGE_SIZE); | |
3109 | if (batch->memsw_nr_pages) | |
3110 | res_counter_uncharge(&batch->memcg->memsw, | |
3111 | batch->memsw_nr_pages * PAGE_SIZE); | |
3c11ecf4 | 3112 | memcg_oom_recover(batch->memcg); |
569b846d KH |
3113 | /* forget this pointer (for sanity check) */ |
3114 | batch->memcg = NULL; | |
3115 | } | |
3116 | ||
e767e056 | 3117 | #ifdef CONFIG_SWAP |
8c7c6e34 | 3118 | /* |
e767e056 | 3119 | * called after __delete_from_swap_cache() and drop "page" account. |
8c7c6e34 KH |
3120 | * memcg information is recorded to swap_cgroup of "ent" |
3121 | */ | |
8a9478ca KH |
3122 | void |
3123 | mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout) | |
8c7c6e34 KH |
3124 | { |
3125 | struct mem_cgroup *memcg; | |
8a9478ca KH |
3126 | int ctype = MEM_CGROUP_CHARGE_TYPE_SWAPOUT; |
3127 | ||
3128 | if (!swapout) /* this was a swap cache but the swap is unused ! */ | |
3129 | ctype = MEM_CGROUP_CHARGE_TYPE_DROP; | |
3130 | ||
3131 | memcg = __mem_cgroup_uncharge_common(page, ctype); | |
8c7c6e34 | 3132 | |
f75ca962 KH |
3133 | /* |
3134 | * record memcg information, if swapout && memcg != NULL, | |
3135 | * mem_cgroup_get() was called in uncharge(). | |
3136 | */ | |
3137 | if (do_swap_account && swapout && memcg) | |
a3b2d692 | 3138 | swap_cgroup_record(ent, css_id(&memcg->css)); |
8c7c6e34 | 3139 | } |
e767e056 | 3140 | #endif |
8c7c6e34 KH |
3141 | |
3142 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
3143 | /* | |
3144 | * called from swap_entry_free(). remove record in swap_cgroup and | |
3145 | * uncharge "memsw" account. | |
3146 | */ | |
3147 | void mem_cgroup_uncharge_swap(swp_entry_t ent) | |
d13d1443 | 3148 | { |
8c7c6e34 | 3149 | struct mem_cgroup *memcg; |
a3b2d692 | 3150 | unsigned short id; |
8c7c6e34 KH |
3151 | |
3152 | if (!do_swap_account) | |
3153 | return; | |
3154 | ||
a3b2d692 KH |
3155 | id = swap_cgroup_record(ent, 0); |
3156 | rcu_read_lock(); | |
3157 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 3158 | if (memcg) { |
a3b2d692 KH |
3159 | /* |
3160 | * We uncharge this because swap is freed. | |
3161 | * This memcg can be obsolete one. We avoid calling css_tryget | |
3162 | */ | |
0c3e73e8 | 3163 | if (!mem_cgroup_is_root(memcg)) |
4e649152 | 3164 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
0c3e73e8 | 3165 | mem_cgroup_swap_statistics(memcg, false); |
8c7c6e34 KH |
3166 | mem_cgroup_put(memcg); |
3167 | } | |
a3b2d692 | 3168 | rcu_read_unlock(); |
d13d1443 | 3169 | } |
02491447 DN |
3170 | |
3171 | /** | |
3172 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
3173 | * @entry: swap entry to be moved | |
3174 | * @from: mem_cgroup which the entry is moved from | |
3175 | * @to: mem_cgroup which the entry is moved to | |
483c30b5 | 3176 | * @need_fixup: whether we should fixup res_counters and refcounts. |
02491447 DN |
3177 | * |
3178 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
3179 | * as the mem_cgroup's id of @from. | |
3180 | * | |
3181 | * Returns 0 on success, -EINVAL on failure. | |
3182 | * | |
3183 | * The caller must have charged to @to, IOW, called res_counter_charge() about | |
3184 | * both res and memsw, and called css_get(). | |
3185 | */ | |
3186 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
483c30b5 | 3187 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
02491447 DN |
3188 | { |
3189 | unsigned short old_id, new_id; | |
3190 | ||
3191 | old_id = css_id(&from->css); | |
3192 | new_id = css_id(&to->css); | |
3193 | ||
3194 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
02491447 | 3195 | mem_cgroup_swap_statistics(from, false); |
483c30b5 | 3196 | mem_cgroup_swap_statistics(to, true); |
02491447 | 3197 | /* |
483c30b5 DN |
3198 | * This function is only called from task migration context now. |
3199 | * It postpones res_counter and refcount handling till the end | |
3200 | * of task migration(mem_cgroup_clear_mc()) for performance | |
3201 | * improvement. But we cannot postpone mem_cgroup_get(to) | |
3202 | * because if the process that has been moved to @to does | |
3203 | * swap-in, the refcount of @to might be decreased to 0. | |
02491447 | 3204 | */ |
02491447 | 3205 | mem_cgroup_get(to); |
483c30b5 DN |
3206 | if (need_fixup) { |
3207 | if (!mem_cgroup_is_root(from)) | |
3208 | res_counter_uncharge(&from->memsw, PAGE_SIZE); | |
3209 | mem_cgroup_put(from); | |
3210 | /* | |
3211 | * we charged both to->res and to->memsw, so we should | |
3212 | * uncharge to->res. | |
3213 | */ | |
3214 | if (!mem_cgroup_is_root(to)) | |
3215 | res_counter_uncharge(&to->res, PAGE_SIZE); | |
483c30b5 | 3216 | } |
02491447 DN |
3217 | return 0; |
3218 | } | |
3219 | return -EINVAL; | |
3220 | } | |
3221 | #else | |
3222 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
483c30b5 | 3223 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
02491447 DN |
3224 | { |
3225 | return -EINVAL; | |
3226 | } | |
8c7c6e34 | 3227 | #endif |
d13d1443 | 3228 | |
ae41be37 | 3229 | /* |
01b1ae63 KH |
3230 | * Before starting migration, account PAGE_SIZE to mem_cgroup that the old |
3231 | * page belongs to. | |
ae41be37 | 3232 | */ |
ac39cf8c | 3233 | int mem_cgroup_prepare_migration(struct page *page, |
ef6a3c63 | 3234 | struct page *newpage, struct mem_cgroup **ptr, gfp_t gfp_mask) |
ae41be37 | 3235 | { |
e8589cc1 | 3236 | struct mem_cgroup *mem = NULL; |
7ec99d62 | 3237 | struct page_cgroup *pc; |
ac39cf8c | 3238 | enum charge_type ctype; |
e8589cc1 | 3239 | int ret = 0; |
8869b8f6 | 3240 | |
56039efa KH |
3241 | *ptr = NULL; |
3242 | ||
ec168510 | 3243 | VM_BUG_ON(PageTransHuge(page)); |
f8d66542 | 3244 | if (mem_cgroup_disabled()) |
4077960e BS |
3245 | return 0; |
3246 | ||
52d4b9ac KH |
3247 | pc = lookup_page_cgroup(page); |
3248 | lock_page_cgroup(pc); | |
3249 | if (PageCgroupUsed(pc)) { | |
e8589cc1 KH |
3250 | mem = pc->mem_cgroup; |
3251 | css_get(&mem->css); | |
ac39cf8c | 3252 | /* |
3253 | * At migrating an anonymous page, its mapcount goes down | |
3254 | * to 0 and uncharge() will be called. But, even if it's fully | |
3255 | * unmapped, migration may fail and this page has to be | |
3256 | * charged again. We set MIGRATION flag here and delay uncharge | |
3257 | * until end_migration() is called | |
3258 | * | |
3259 | * Corner Case Thinking | |
3260 | * A) | |
3261 | * When the old page was mapped as Anon and it's unmap-and-freed | |
3262 | * while migration was ongoing. | |
3263 | * If unmap finds the old page, uncharge() of it will be delayed | |
3264 | * until end_migration(). If unmap finds a new page, it's | |
3265 | * uncharged when it make mapcount to be 1->0. If unmap code | |
3266 | * finds swap_migration_entry, the new page will not be mapped | |
3267 | * and end_migration() will find it(mapcount==0). | |
3268 | * | |
3269 | * B) | |
3270 | * When the old page was mapped but migraion fails, the kernel | |
3271 | * remaps it. A charge for it is kept by MIGRATION flag even | |
3272 | * if mapcount goes down to 0. We can do remap successfully | |
3273 | * without charging it again. | |
3274 | * | |
3275 | * C) | |
3276 | * The "old" page is under lock_page() until the end of | |
3277 | * migration, so, the old page itself will not be swapped-out. | |
3278 | * If the new page is swapped out before end_migraton, our | |
3279 | * hook to usual swap-out path will catch the event. | |
3280 | */ | |
3281 | if (PageAnon(page)) | |
3282 | SetPageCgroupMigration(pc); | |
e8589cc1 | 3283 | } |
52d4b9ac | 3284 | unlock_page_cgroup(pc); |
ac39cf8c | 3285 | /* |
3286 | * If the page is not charged at this point, | |
3287 | * we return here. | |
3288 | */ | |
3289 | if (!mem) | |
3290 | return 0; | |
01b1ae63 | 3291 | |
93d5c9be | 3292 | *ptr = mem; |
7ec99d62 | 3293 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, 1, ptr, false); |
ac39cf8c | 3294 | css_put(&mem->css);/* drop extra refcnt */ |
3295 | if (ret || *ptr == NULL) { | |
3296 | if (PageAnon(page)) { | |
3297 | lock_page_cgroup(pc); | |
3298 | ClearPageCgroupMigration(pc); | |
3299 | unlock_page_cgroup(pc); | |
3300 | /* | |
3301 | * The old page may be fully unmapped while we kept it. | |
3302 | */ | |
3303 | mem_cgroup_uncharge_page(page); | |
3304 | } | |
3305 | return -ENOMEM; | |
e8589cc1 | 3306 | } |
ac39cf8c | 3307 | /* |
3308 | * We charge new page before it's used/mapped. So, even if unlock_page() | |
3309 | * is called before end_migration, we can catch all events on this new | |
3310 | * page. In the case new page is migrated but not remapped, new page's | |
3311 | * mapcount will be finally 0 and we call uncharge in end_migration(). | |
3312 | */ | |
3313 | pc = lookup_page_cgroup(newpage); | |
3314 | if (PageAnon(page)) | |
3315 | ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED; | |
3316 | else if (page_is_file_cache(page)) | |
3317 | ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; | |
3318 | else | |
3319 | ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; | |
7ec99d62 | 3320 | __mem_cgroup_commit_charge(mem, page, 1, pc, ctype); |
e8589cc1 | 3321 | return ret; |
ae41be37 | 3322 | } |
8869b8f6 | 3323 | |
69029cd5 | 3324 | /* remove redundant charge if migration failed*/ |
01b1ae63 | 3325 | void mem_cgroup_end_migration(struct mem_cgroup *mem, |
50de1dd9 | 3326 | struct page *oldpage, struct page *newpage, bool migration_ok) |
ae41be37 | 3327 | { |
ac39cf8c | 3328 | struct page *used, *unused; |
01b1ae63 | 3329 | struct page_cgroup *pc; |
01b1ae63 KH |
3330 | |
3331 | if (!mem) | |
3332 | return; | |
ac39cf8c | 3333 | /* blocks rmdir() */ |
88703267 | 3334 | cgroup_exclude_rmdir(&mem->css); |
50de1dd9 | 3335 | if (!migration_ok) { |
ac39cf8c | 3336 | used = oldpage; |
3337 | unused = newpage; | |
01b1ae63 | 3338 | } else { |
ac39cf8c | 3339 | used = newpage; |
01b1ae63 KH |
3340 | unused = oldpage; |
3341 | } | |
69029cd5 | 3342 | /* |
ac39cf8c | 3343 | * We disallowed uncharge of pages under migration because mapcount |
3344 | * of the page goes down to zero, temporarly. | |
3345 | * Clear the flag and check the page should be charged. | |
01b1ae63 | 3346 | */ |
ac39cf8c | 3347 | pc = lookup_page_cgroup(oldpage); |
3348 | lock_page_cgroup(pc); | |
3349 | ClearPageCgroupMigration(pc); | |
3350 | unlock_page_cgroup(pc); | |
01b1ae63 | 3351 | |
ac39cf8c | 3352 | __mem_cgroup_uncharge_common(unused, MEM_CGROUP_CHARGE_TYPE_FORCE); |
3353 | ||
01b1ae63 | 3354 | /* |
ac39cf8c | 3355 | * If a page is a file cache, radix-tree replacement is very atomic |
3356 | * and we can skip this check. When it was an Anon page, its mapcount | |
3357 | * goes down to 0. But because we added MIGRATION flage, it's not | |
3358 | * uncharged yet. There are several case but page->mapcount check | |
3359 | * and USED bit check in mem_cgroup_uncharge_page() will do enough | |
3360 | * check. (see prepare_charge() also) | |
69029cd5 | 3361 | */ |
ac39cf8c | 3362 | if (PageAnon(used)) |
3363 | mem_cgroup_uncharge_page(used); | |
88703267 | 3364 | /* |
ac39cf8c | 3365 | * At migration, we may charge account against cgroup which has no |
3366 | * tasks. | |
88703267 KH |
3367 | * So, rmdir()->pre_destroy() can be called while we do this charge. |
3368 | * In that case, we need to call pre_destroy() again. check it here. | |
3369 | */ | |
3370 | cgroup_release_and_wakeup_rmdir(&mem->css); | |
ae41be37 | 3371 | } |
78fb7466 | 3372 | |
c9b0ed51 | 3373 | /* |
ae3abae6 DN |
3374 | * A call to try to shrink memory usage on charge failure at shmem's swapin. |
3375 | * Calling hierarchical_reclaim is not enough because we should update | |
3376 | * last_oom_jiffies to prevent pagefault_out_of_memory from invoking global OOM. | |
3377 | * Moreover considering hierarchy, we should reclaim from the mem_over_limit, | |
3378 | * not from the memcg which this page would be charged to. | |
3379 | * try_charge_swapin does all of these works properly. | |
c9b0ed51 | 3380 | */ |
ae3abae6 | 3381 | int mem_cgroup_shmem_charge_fallback(struct page *page, |
b5a84319 KH |
3382 | struct mm_struct *mm, |
3383 | gfp_t gfp_mask) | |
c9b0ed51 | 3384 | { |
56039efa | 3385 | struct mem_cgroup *mem; |
ae3abae6 | 3386 | int ret; |
c9b0ed51 | 3387 | |
f8d66542 | 3388 | if (mem_cgroup_disabled()) |
cede86ac | 3389 | return 0; |
c9b0ed51 | 3390 | |
ae3abae6 DN |
3391 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); |
3392 | if (!ret) | |
3393 | mem_cgroup_cancel_charge_swapin(mem); /* it does !mem check */ | |
c9b0ed51 | 3394 | |
ae3abae6 | 3395 | return ret; |
c9b0ed51 KH |
3396 | } |
3397 | ||
f212ad7c DN |
3398 | #ifdef CONFIG_DEBUG_VM |
3399 | static struct page_cgroup *lookup_page_cgroup_used(struct page *page) | |
3400 | { | |
3401 | struct page_cgroup *pc; | |
3402 | ||
3403 | pc = lookup_page_cgroup(page); | |
3404 | if (likely(pc) && PageCgroupUsed(pc)) | |
3405 | return pc; | |
3406 | return NULL; | |
3407 | } | |
3408 | ||
3409 | bool mem_cgroup_bad_page_check(struct page *page) | |
3410 | { | |
3411 | if (mem_cgroup_disabled()) | |
3412 | return false; | |
3413 | ||
3414 | return lookup_page_cgroup_used(page) != NULL; | |
3415 | } | |
3416 | ||
3417 | void mem_cgroup_print_bad_page(struct page *page) | |
3418 | { | |
3419 | struct page_cgroup *pc; | |
3420 | ||
3421 | pc = lookup_page_cgroup_used(page); | |
3422 | if (pc) { | |
3423 | int ret = -1; | |
3424 | char *path; | |
3425 | ||
3426 | printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p", | |
3427 | pc, pc->flags, pc->mem_cgroup); | |
3428 | ||
3429 | path = kmalloc(PATH_MAX, GFP_KERNEL); | |
3430 | if (path) { | |
3431 | rcu_read_lock(); | |
3432 | ret = cgroup_path(pc->mem_cgroup->css.cgroup, | |
3433 | path, PATH_MAX); | |
3434 | rcu_read_unlock(); | |
3435 | } | |
3436 | ||
3437 | printk(KERN_CONT "(%s)\n", | |
3438 | (ret < 0) ? "cannot get the path" : path); | |
3439 | kfree(path); | |
3440 | } | |
3441 | } | |
3442 | #endif | |
3443 | ||
8c7c6e34 KH |
3444 | static DEFINE_MUTEX(set_limit_mutex); |
3445 | ||
d38d2a75 | 3446 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
8c7c6e34 | 3447 | unsigned long long val) |
628f4235 | 3448 | { |
81d39c20 | 3449 | int retry_count; |
3c11ecf4 | 3450 | u64 memswlimit, memlimit; |
628f4235 | 3451 | int ret = 0; |
81d39c20 KH |
3452 | int children = mem_cgroup_count_children(memcg); |
3453 | u64 curusage, oldusage; | |
3c11ecf4 | 3454 | int enlarge; |
81d39c20 KH |
3455 | |
3456 | /* | |
3457 | * For keeping hierarchical_reclaim simple, how long we should retry | |
3458 | * is depends on callers. We set our retry-count to be function | |
3459 | * of # of children which we should visit in this loop. | |
3460 | */ | |
3461 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; | |
3462 | ||
3463 | oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); | |
628f4235 | 3464 | |
3c11ecf4 | 3465 | enlarge = 0; |
8c7c6e34 | 3466 | while (retry_count) { |
628f4235 KH |
3467 | if (signal_pending(current)) { |
3468 | ret = -EINTR; | |
3469 | break; | |
3470 | } | |
8c7c6e34 KH |
3471 | /* |
3472 | * Rather than hide all in some function, I do this in | |
3473 | * open coded manner. You see what this really does. | |
3474 | * We have to guarantee mem->res.limit < mem->memsw.limit. | |
3475 | */ | |
3476 | mutex_lock(&set_limit_mutex); | |
3477 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
3478 | if (memswlimit < val) { | |
3479 | ret = -EINVAL; | |
3480 | mutex_unlock(&set_limit_mutex); | |
628f4235 KH |
3481 | break; |
3482 | } | |
3c11ecf4 KH |
3483 | |
3484 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3485 | if (memlimit < val) | |
3486 | enlarge = 1; | |
3487 | ||
8c7c6e34 | 3488 | ret = res_counter_set_limit(&memcg->res, val); |
22a668d7 KH |
3489 | if (!ret) { |
3490 | if (memswlimit == val) | |
3491 | memcg->memsw_is_minimum = true; | |
3492 | else | |
3493 | memcg->memsw_is_minimum = false; | |
3494 | } | |
8c7c6e34 KH |
3495 | mutex_unlock(&set_limit_mutex); |
3496 | ||
3497 | if (!ret) | |
3498 | break; | |
3499 | ||
aa20d489 | 3500 | mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, |
0ae5e89c YH |
3501 | MEM_CGROUP_RECLAIM_SHRINK, |
3502 | NULL); | |
81d39c20 KH |
3503 | curusage = res_counter_read_u64(&memcg->res, RES_USAGE); |
3504 | /* Usage is reduced ? */ | |
3505 | if (curusage >= oldusage) | |
3506 | retry_count--; | |
3507 | else | |
3508 | oldusage = curusage; | |
8c7c6e34 | 3509 | } |
3c11ecf4 KH |
3510 | if (!ret && enlarge) |
3511 | memcg_oom_recover(memcg); | |
14797e23 | 3512 | |
8c7c6e34 KH |
3513 | return ret; |
3514 | } | |
3515 | ||
338c8431 LZ |
3516 | static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, |
3517 | unsigned long long val) | |
8c7c6e34 | 3518 | { |
81d39c20 | 3519 | int retry_count; |
3c11ecf4 | 3520 | u64 memlimit, memswlimit, oldusage, curusage; |
81d39c20 KH |
3521 | int children = mem_cgroup_count_children(memcg); |
3522 | int ret = -EBUSY; | |
3c11ecf4 | 3523 | int enlarge = 0; |
8c7c6e34 | 3524 | |
81d39c20 KH |
3525 | /* see mem_cgroup_resize_res_limit */ |
3526 | retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; | |
3527 | oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); | |
8c7c6e34 KH |
3528 | while (retry_count) { |
3529 | if (signal_pending(current)) { | |
3530 | ret = -EINTR; | |
3531 | break; | |
3532 | } | |
3533 | /* | |
3534 | * Rather than hide all in some function, I do this in | |
3535 | * open coded manner. You see what this really does. | |
3536 | * We have to guarantee mem->res.limit < mem->memsw.limit. | |
3537 | */ | |
3538 | mutex_lock(&set_limit_mutex); | |
3539 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3540 | if (memlimit > val) { | |
3541 | ret = -EINVAL; | |
3542 | mutex_unlock(&set_limit_mutex); | |
3543 | break; | |
3544 | } | |
3c11ecf4 KH |
3545 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
3546 | if (memswlimit < val) | |
3547 | enlarge = 1; | |
8c7c6e34 | 3548 | ret = res_counter_set_limit(&memcg->memsw, val); |
22a668d7 KH |
3549 | if (!ret) { |
3550 | if (memlimit == val) | |
3551 | memcg->memsw_is_minimum = true; | |
3552 | else | |
3553 | memcg->memsw_is_minimum = false; | |
3554 | } | |
8c7c6e34 KH |
3555 | mutex_unlock(&set_limit_mutex); |
3556 | ||
3557 | if (!ret) | |
3558 | break; | |
3559 | ||
4e416953 | 3560 | mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, |
75822b44 | 3561 | MEM_CGROUP_RECLAIM_NOSWAP | |
0ae5e89c YH |
3562 | MEM_CGROUP_RECLAIM_SHRINK, |
3563 | NULL); | |
8c7c6e34 | 3564 | curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); |
81d39c20 | 3565 | /* Usage is reduced ? */ |
8c7c6e34 | 3566 | if (curusage >= oldusage) |
628f4235 | 3567 | retry_count--; |
81d39c20 KH |
3568 | else |
3569 | oldusage = curusage; | |
628f4235 | 3570 | } |
3c11ecf4 KH |
3571 | if (!ret && enlarge) |
3572 | memcg_oom_recover(memcg); | |
628f4235 KH |
3573 | return ret; |
3574 | } | |
3575 | ||
4e416953 | 3576 | unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, |
0ae5e89c YH |
3577 | gfp_t gfp_mask, |
3578 | unsigned long *total_scanned) | |
4e416953 BS |
3579 | { |
3580 | unsigned long nr_reclaimed = 0; | |
3581 | struct mem_cgroup_per_zone *mz, *next_mz = NULL; | |
3582 | unsigned long reclaimed; | |
3583 | int loop = 0; | |
3584 | struct mem_cgroup_tree_per_zone *mctz; | |
ef8745c1 | 3585 | unsigned long long excess; |
0ae5e89c | 3586 | unsigned long nr_scanned; |
4e416953 BS |
3587 | |
3588 | if (order > 0) | |
3589 | return 0; | |
3590 | ||
00918b6a | 3591 | mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone)); |
4e416953 BS |
3592 | /* |
3593 | * This loop can run a while, specially if mem_cgroup's continuously | |
3594 | * keep exceeding their soft limit and putting the system under | |
3595 | * pressure | |
3596 | */ | |
3597 | do { | |
3598 | if (next_mz) | |
3599 | mz = next_mz; | |
3600 | else | |
3601 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
3602 | if (!mz) | |
3603 | break; | |
3604 | ||
0ae5e89c | 3605 | nr_scanned = 0; |
4e416953 BS |
3606 | reclaimed = mem_cgroup_hierarchical_reclaim(mz->mem, zone, |
3607 | gfp_mask, | |
0ae5e89c YH |
3608 | MEM_CGROUP_RECLAIM_SOFT, |
3609 | &nr_scanned); | |
4e416953 | 3610 | nr_reclaimed += reclaimed; |
0ae5e89c | 3611 | *total_scanned += nr_scanned; |
4e416953 BS |
3612 | spin_lock(&mctz->lock); |
3613 | ||
3614 | /* | |
3615 | * If we failed to reclaim anything from this memory cgroup | |
3616 | * it is time to move on to the next cgroup | |
3617 | */ | |
3618 | next_mz = NULL; | |
3619 | if (!reclaimed) { | |
3620 | do { | |
3621 | /* | |
3622 | * Loop until we find yet another one. | |
3623 | * | |
3624 | * By the time we get the soft_limit lock | |
3625 | * again, someone might have aded the | |
3626 | * group back on the RB tree. Iterate to | |
3627 | * make sure we get a different mem. | |
3628 | * mem_cgroup_largest_soft_limit_node returns | |
3629 | * NULL if no other cgroup is present on | |
3630 | * the tree | |
3631 | */ | |
3632 | next_mz = | |
3633 | __mem_cgroup_largest_soft_limit_node(mctz); | |
39cc98f1 | 3634 | if (next_mz == mz) |
4e416953 | 3635 | css_put(&next_mz->mem->css); |
39cc98f1 | 3636 | else /* next_mz == NULL or other memcg */ |
4e416953 BS |
3637 | break; |
3638 | } while (1); | |
3639 | } | |
4e416953 | 3640 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); |
ef8745c1 | 3641 | excess = res_counter_soft_limit_excess(&mz->mem->res); |
4e416953 BS |
3642 | /* |
3643 | * One school of thought says that we should not add | |
3644 | * back the node to the tree if reclaim returns 0. | |
3645 | * But our reclaim could return 0, simply because due | |
3646 | * to priority we are exposing a smaller subset of | |
3647 | * memory to reclaim from. Consider this as a longer | |
3648 | * term TODO. | |
3649 | */ | |
ef8745c1 KH |
3650 | /* If excess == 0, no tree ops */ |
3651 | __mem_cgroup_insert_exceeded(mz->mem, mz, mctz, excess); | |
4e416953 BS |
3652 | spin_unlock(&mctz->lock); |
3653 | css_put(&mz->mem->css); | |
3654 | loop++; | |
3655 | /* | |
3656 | * Could not reclaim anything and there are no more | |
3657 | * mem cgroups to try or we seem to be looping without | |
3658 | * reclaiming anything. | |
3659 | */ | |
3660 | if (!nr_reclaimed && | |
3661 | (next_mz == NULL || | |
3662 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
3663 | break; | |
3664 | } while (!nr_reclaimed); | |
3665 | if (next_mz) | |
3666 | css_put(&next_mz->mem->css); | |
3667 | return nr_reclaimed; | |
3668 | } | |
3669 | ||
cc847582 KH |
3670 | /* |
3671 | * This routine traverse page_cgroup in given list and drop them all. | |
cc847582 KH |
3672 | * *And* this routine doesn't reclaim page itself, just removes page_cgroup. |
3673 | */ | |
f817ed48 | 3674 | static int mem_cgroup_force_empty_list(struct mem_cgroup *mem, |
08e552c6 | 3675 | int node, int zid, enum lru_list lru) |
cc847582 | 3676 | { |
08e552c6 KH |
3677 | struct zone *zone; |
3678 | struct mem_cgroup_per_zone *mz; | |
f817ed48 | 3679 | struct page_cgroup *pc, *busy; |
08e552c6 | 3680 | unsigned long flags, loop; |
072c56c1 | 3681 | struct list_head *list; |
f817ed48 | 3682 | int ret = 0; |
072c56c1 | 3683 | |
08e552c6 KH |
3684 | zone = &NODE_DATA(node)->node_zones[zid]; |
3685 | mz = mem_cgroup_zoneinfo(mem, node, zid); | |
b69408e8 | 3686 | list = &mz->lists[lru]; |
cc847582 | 3687 | |
f817ed48 KH |
3688 | loop = MEM_CGROUP_ZSTAT(mz, lru); |
3689 | /* give some margin against EBUSY etc...*/ | |
3690 | loop += 256; | |
3691 | busy = NULL; | |
3692 | while (loop--) { | |
5564e88b JW |
3693 | struct page *page; |
3694 | ||
f817ed48 | 3695 | ret = 0; |
08e552c6 | 3696 | spin_lock_irqsave(&zone->lru_lock, flags); |
f817ed48 | 3697 | if (list_empty(list)) { |
08e552c6 | 3698 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
52d4b9ac | 3699 | break; |
f817ed48 KH |
3700 | } |
3701 | pc = list_entry(list->prev, struct page_cgroup, lru); | |
3702 | if (busy == pc) { | |
3703 | list_move(&pc->lru, list); | |
648bcc77 | 3704 | busy = NULL; |
08e552c6 | 3705 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 KH |
3706 | continue; |
3707 | } | |
08e552c6 | 3708 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 | 3709 | |
6b3ae58e | 3710 | page = lookup_cgroup_page(pc); |
5564e88b JW |
3711 | |
3712 | ret = mem_cgroup_move_parent(page, pc, mem, GFP_KERNEL); | |
f817ed48 | 3713 | if (ret == -ENOMEM) |
52d4b9ac | 3714 | break; |
f817ed48 KH |
3715 | |
3716 | if (ret == -EBUSY || ret == -EINVAL) { | |
3717 | /* found lock contention or "pc" is obsolete. */ | |
3718 | busy = pc; | |
3719 | cond_resched(); | |
3720 | } else | |
3721 | busy = NULL; | |
cc847582 | 3722 | } |
08e552c6 | 3723 | |
f817ed48 KH |
3724 | if (!ret && !list_empty(list)) |
3725 | return -EBUSY; | |
3726 | return ret; | |
cc847582 KH |
3727 | } |
3728 | ||
3729 | /* | |
3730 | * make mem_cgroup's charge to be 0 if there is no task. | |
3731 | * This enables deleting this mem_cgroup. | |
3732 | */ | |
c1e862c1 | 3733 | static int mem_cgroup_force_empty(struct mem_cgroup *mem, bool free_all) |
cc847582 | 3734 | { |
f817ed48 KH |
3735 | int ret; |
3736 | int node, zid, shrink; | |
3737 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
c1e862c1 | 3738 | struct cgroup *cgrp = mem->css.cgroup; |
8869b8f6 | 3739 | |
cc847582 | 3740 | css_get(&mem->css); |
f817ed48 KH |
3741 | |
3742 | shrink = 0; | |
c1e862c1 KH |
3743 | /* should free all ? */ |
3744 | if (free_all) | |
3745 | goto try_to_free; | |
f817ed48 | 3746 | move_account: |
fce66477 | 3747 | do { |
f817ed48 | 3748 | ret = -EBUSY; |
c1e862c1 KH |
3749 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children)) |
3750 | goto out; | |
3751 | ret = -EINTR; | |
3752 | if (signal_pending(current)) | |
cc847582 | 3753 | goto out; |
52d4b9ac KH |
3754 | /* This is for making all *used* pages to be on LRU. */ |
3755 | lru_add_drain_all(); | |
cdec2e42 | 3756 | drain_all_stock_sync(); |
f817ed48 | 3757 | ret = 0; |
32047e2a | 3758 | mem_cgroup_start_move(mem); |
299b4eaa | 3759 | for_each_node_state(node, N_HIGH_MEMORY) { |
f817ed48 | 3760 | for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { |
b69408e8 | 3761 | enum lru_list l; |
f817ed48 KH |
3762 | for_each_lru(l) { |
3763 | ret = mem_cgroup_force_empty_list(mem, | |
08e552c6 | 3764 | node, zid, l); |
f817ed48 KH |
3765 | if (ret) |
3766 | break; | |
3767 | } | |
1ecaab2b | 3768 | } |
f817ed48 KH |
3769 | if (ret) |
3770 | break; | |
3771 | } | |
32047e2a | 3772 | mem_cgroup_end_move(mem); |
3c11ecf4 | 3773 | memcg_oom_recover(mem); |
f817ed48 KH |
3774 | /* it seems parent cgroup doesn't have enough mem */ |
3775 | if (ret == -ENOMEM) | |
3776 | goto try_to_free; | |
52d4b9ac | 3777 | cond_resched(); |
fce66477 DN |
3778 | /* "ret" should also be checked to ensure all lists are empty. */ |
3779 | } while (mem->res.usage > 0 || ret); | |
cc847582 KH |
3780 | out: |
3781 | css_put(&mem->css); | |
3782 | return ret; | |
f817ed48 KH |
3783 | |
3784 | try_to_free: | |
c1e862c1 KH |
3785 | /* returns EBUSY if there is a task or if we come here twice. */ |
3786 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) { | |
f817ed48 KH |
3787 | ret = -EBUSY; |
3788 | goto out; | |
3789 | } | |
c1e862c1 KH |
3790 | /* we call try-to-free pages for make this cgroup empty */ |
3791 | lru_add_drain_all(); | |
f817ed48 KH |
3792 | /* try to free all pages in this cgroup */ |
3793 | shrink = 1; | |
3794 | while (nr_retries && mem->res.usage > 0) { | |
3795 | int progress; | |
c1e862c1 KH |
3796 | |
3797 | if (signal_pending(current)) { | |
3798 | ret = -EINTR; | |
3799 | goto out; | |
3800 | } | |
a7885eb8 | 3801 | progress = try_to_free_mem_cgroup_pages(mem, GFP_KERNEL, |
1f4c025b | 3802 | false); |
c1e862c1 | 3803 | if (!progress) { |
f817ed48 | 3804 | nr_retries--; |
c1e862c1 | 3805 | /* maybe some writeback is necessary */ |
8aa7e847 | 3806 | congestion_wait(BLK_RW_ASYNC, HZ/10); |
c1e862c1 | 3807 | } |
f817ed48 KH |
3808 | |
3809 | } | |
08e552c6 | 3810 | lru_add_drain(); |
f817ed48 | 3811 | /* try move_account...there may be some *locked* pages. */ |
fce66477 | 3812 | goto move_account; |
cc847582 KH |
3813 | } |
3814 | ||
c1e862c1 KH |
3815 | int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event) |
3816 | { | |
3817 | return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true); | |
3818 | } | |
3819 | ||
3820 | ||
18f59ea7 BS |
3821 | static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft) |
3822 | { | |
3823 | return mem_cgroup_from_cont(cont)->use_hierarchy; | |
3824 | } | |
3825 | ||
3826 | static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft, | |
3827 | u64 val) | |
3828 | { | |
3829 | int retval = 0; | |
3830 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); | |
3831 | struct cgroup *parent = cont->parent; | |
3832 | struct mem_cgroup *parent_mem = NULL; | |
3833 | ||
3834 | if (parent) | |
3835 | parent_mem = mem_cgroup_from_cont(parent); | |
3836 | ||
3837 | cgroup_lock(); | |
3838 | /* | |
af901ca1 | 3839 | * If parent's use_hierarchy is set, we can't make any modifications |
18f59ea7 BS |
3840 | * in the child subtrees. If it is unset, then the change can |
3841 | * occur, provided the current cgroup has no children. | |
3842 | * | |
3843 | * For the root cgroup, parent_mem is NULL, we allow value to be | |
3844 | * set if there are no children. | |
3845 | */ | |
3846 | if ((!parent_mem || !parent_mem->use_hierarchy) && | |
3847 | (val == 1 || val == 0)) { | |
3848 | if (list_empty(&cont->children)) | |
3849 | mem->use_hierarchy = val; | |
3850 | else | |
3851 | retval = -EBUSY; | |
3852 | } else | |
3853 | retval = -EINVAL; | |
3854 | cgroup_unlock(); | |
3855 | ||
3856 | return retval; | |
3857 | } | |
3858 | ||
0c3e73e8 | 3859 | |
7a159cc9 JW |
3860 | static unsigned long mem_cgroup_recursive_stat(struct mem_cgroup *mem, |
3861 | enum mem_cgroup_stat_index idx) | |
0c3e73e8 | 3862 | { |
7d74b06f | 3863 | struct mem_cgroup *iter; |
7a159cc9 | 3864 | long val = 0; |
0c3e73e8 | 3865 | |
7a159cc9 | 3866 | /* Per-cpu values can be negative, use a signed accumulator */ |
7d74b06f KH |
3867 | for_each_mem_cgroup_tree(iter, mem) |
3868 | val += mem_cgroup_read_stat(iter, idx); | |
3869 | ||
3870 | if (val < 0) /* race ? */ | |
3871 | val = 0; | |
3872 | return val; | |
0c3e73e8 BS |
3873 | } |
3874 | ||
104f3928 KS |
3875 | static inline u64 mem_cgroup_usage(struct mem_cgroup *mem, bool swap) |
3876 | { | |
7d74b06f | 3877 | u64 val; |
104f3928 KS |
3878 | |
3879 | if (!mem_cgroup_is_root(mem)) { | |
3880 | if (!swap) | |
3881 | return res_counter_read_u64(&mem->res, RES_USAGE); | |
3882 | else | |
3883 | return res_counter_read_u64(&mem->memsw, RES_USAGE); | |
3884 | } | |
3885 | ||
7a159cc9 JW |
3886 | val = mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_CACHE); |
3887 | val += mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_RSS); | |
104f3928 | 3888 | |
7d74b06f | 3889 | if (swap) |
7a159cc9 | 3890 | val += mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_SWAPOUT); |
104f3928 KS |
3891 | |
3892 | return val << PAGE_SHIFT; | |
3893 | } | |
3894 | ||
2c3daa72 | 3895 | static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) |
8cdea7c0 | 3896 | { |
8c7c6e34 | 3897 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
104f3928 | 3898 | u64 val; |
8c7c6e34 KH |
3899 | int type, name; |
3900 | ||
3901 | type = MEMFILE_TYPE(cft->private); | |
3902 | name = MEMFILE_ATTR(cft->private); | |
3903 | switch (type) { | |
3904 | case _MEM: | |
104f3928 KS |
3905 | if (name == RES_USAGE) |
3906 | val = mem_cgroup_usage(mem, false); | |
3907 | else | |
0c3e73e8 | 3908 | val = res_counter_read_u64(&mem->res, name); |
8c7c6e34 KH |
3909 | break; |
3910 | case _MEMSWAP: | |
104f3928 KS |
3911 | if (name == RES_USAGE) |
3912 | val = mem_cgroup_usage(mem, true); | |
3913 | else | |
0c3e73e8 | 3914 | val = res_counter_read_u64(&mem->memsw, name); |
8c7c6e34 KH |
3915 | break; |
3916 | default: | |
3917 | BUG(); | |
3918 | break; | |
3919 | } | |
3920 | return val; | |
8cdea7c0 | 3921 | } |
628f4235 KH |
3922 | /* |
3923 | * The user of this function is... | |
3924 | * RES_LIMIT. | |
3925 | */ | |
856c13aa PM |
3926 | static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, |
3927 | const char *buffer) | |
8cdea7c0 | 3928 | { |
628f4235 | 3929 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
8c7c6e34 | 3930 | int type, name; |
628f4235 KH |
3931 | unsigned long long val; |
3932 | int ret; | |
3933 | ||
8c7c6e34 KH |
3934 | type = MEMFILE_TYPE(cft->private); |
3935 | name = MEMFILE_ATTR(cft->private); | |
3936 | switch (name) { | |
628f4235 | 3937 | case RES_LIMIT: |
4b3bde4c BS |
3938 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
3939 | ret = -EINVAL; | |
3940 | break; | |
3941 | } | |
628f4235 KH |
3942 | /* This function does all necessary parse...reuse it */ |
3943 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
8c7c6e34 KH |
3944 | if (ret) |
3945 | break; | |
3946 | if (type == _MEM) | |
628f4235 | 3947 | ret = mem_cgroup_resize_limit(memcg, val); |
8c7c6e34 KH |
3948 | else |
3949 | ret = mem_cgroup_resize_memsw_limit(memcg, val); | |
628f4235 | 3950 | break; |
296c81d8 BS |
3951 | case RES_SOFT_LIMIT: |
3952 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
3953 | if (ret) | |
3954 | break; | |
3955 | /* | |
3956 | * For memsw, soft limits are hard to implement in terms | |
3957 | * of semantics, for now, we support soft limits for | |
3958 | * control without swap | |
3959 | */ | |
3960 | if (type == _MEM) | |
3961 | ret = res_counter_set_soft_limit(&memcg->res, val); | |
3962 | else | |
3963 | ret = -EINVAL; | |
3964 | break; | |
628f4235 KH |
3965 | default: |
3966 | ret = -EINVAL; /* should be BUG() ? */ | |
3967 | break; | |
3968 | } | |
3969 | return ret; | |
8cdea7c0 BS |
3970 | } |
3971 | ||
fee7b548 KH |
3972 | static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, |
3973 | unsigned long long *mem_limit, unsigned long long *memsw_limit) | |
3974 | { | |
3975 | struct cgroup *cgroup; | |
3976 | unsigned long long min_limit, min_memsw_limit, tmp; | |
3977 | ||
3978 | min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3979 | min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
3980 | cgroup = memcg->css.cgroup; | |
3981 | if (!memcg->use_hierarchy) | |
3982 | goto out; | |
3983 | ||
3984 | while (cgroup->parent) { | |
3985 | cgroup = cgroup->parent; | |
3986 | memcg = mem_cgroup_from_cont(cgroup); | |
3987 | if (!memcg->use_hierarchy) | |
3988 | break; | |
3989 | tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3990 | min_limit = min(min_limit, tmp); | |
3991 | tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
3992 | min_memsw_limit = min(min_memsw_limit, tmp); | |
3993 | } | |
3994 | out: | |
3995 | *mem_limit = min_limit; | |
3996 | *memsw_limit = min_memsw_limit; | |
3997 | return; | |
3998 | } | |
3999 | ||
29f2a4da | 4000 | static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) |
c84872e1 PE |
4001 | { |
4002 | struct mem_cgroup *mem; | |
8c7c6e34 | 4003 | int type, name; |
c84872e1 PE |
4004 | |
4005 | mem = mem_cgroup_from_cont(cont); | |
8c7c6e34 KH |
4006 | type = MEMFILE_TYPE(event); |
4007 | name = MEMFILE_ATTR(event); | |
4008 | switch (name) { | |
29f2a4da | 4009 | case RES_MAX_USAGE: |
8c7c6e34 KH |
4010 | if (type == _MEM) |
4011 | res_counter_reset_max(&mem->res); | |
4012 | else | |
4013 | res_counter_reset_max(&mem->memsw); | |
29f2a4da PE |
4014 | break; |
4015 | case RES_FAILCNT: | |
8c7c6e34 KH |
4016 | if (type == _MEM) |
4017 | res_counter_reset_failcnt(&mem->res); | |
4018 | else | |
4019 | res_counter_reset_failcnt(&mem->memsw); | |
29f2a4da PE |
4020 | break; |
4021 | } | |
f64c3f54 | 4022 | |
85cc59db | 4023 | return 0; |
c84872e1 PE |
4024 | } |
4025 | ||
7dc74be0 DN |
4026 | static u64 mem_cgroup_move_charge_read(struct cgroup *cgrp, |
4027 | struct cftype *cft) | |
4028 | { | |
4029 | return mem_cgroup_from_cont(cgrp)->move_charge_at_immigrate; | |
4030 | } | |
4031 | ||
02491447 | 4032 | #ifdef CONFIG_MMU |
7dc74be0 DN |
4033 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, |
4034 | struct cftype *cft, u64 val) | |
4035 | { | |
4036 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4037 | ||
4038 | if (val >= (1 << NR_MOVE_TYPE)) | |
4039 | return -EINVAL; | |
4040 | /* | |
4041 | * We check this value several times in both in can_attach() and | |
4042 | * attach(), so we need cgroup lock to prevent this value from being | |
4043 | * inconsistent. | |
4044 | */ | |
4045 | cgroup_lock(); | |
4046 | mem->move_charge_at_immigrate = val; | |
4047 | cgroup_unlock(); | |
4048 | ||
4049 | return 0; | |
4050 | } | |
02491447 DN |
4051 | #else |
4052 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, | |
4053 | struct cftype *cft, u64 val) | |
4054 | { | |
4055 | return -ENOSYS; | |
4056 | } | |
4057 | #endif | |
7dc74be0 | 4058 | |
14067bb3 KH |
4059 | |
4060 | /* For read statistics */ | |
4061 | enum { | |
4062 | MCS_CACHE, | |
4063 | MCS_RSS, | |
d8046582 | 4064 | MCS_FILE_MAPPED, |
14067bb3 KH |
4065 | MCS_PGPGIN, |
4066 | MCS_PGPGOUT, | |
1dd3a273 | 4067 | MCS_SWAP, |
456f998e YH |
4068 | MCS_PGFAULT, |
4069 | MCS_PGMAJFAULT, | |
14067bb3 KH |
4070 | MCS_INACTIVE_ANON, |
4071 | MCS_ACTIVE_ANON, | |
4072 | MCS_INACTIVE_FILE, | |
4073 | MCS_ACTIVE_FILE, | |
4074 | MCS_UNEVICTABLE, | |
4075 | NR_MCS_STAT, | |
4076 | }; | |
4077 | ||
4078 | struct mcs_total_stat { | |
4079 | s64 stat[NR_MCS_STAT]; | |
d2ceb9b7 KH |
4080 | }; |
4081 | ||
14067bb3 KH |
4082 | struct { |
4083 | char *local_name; | |
4084 | char *total_name; | |
4085 | } memcg_stat_strings[NR_MCS_STAT] = { | |
4086 | {"cache", "total_cache"}, | |
4087 | {"rss", "total_rss"}, | |
d69b042f | 4088 | {"mapped_file", "total_mapped_file"}, |
14067bb3 KH |
4089 | {"pgpgin", "total_pgpgin"}, |
4090 | {"pgpgout", "total_pgpgout"}, | |
1dd3a273 | 4091 | {"swap", "total_swap"}, |
456f998e YH |
4092 | {"pgfault", "total_pgfault"}, |
4093 | {"pgmajfault", "total_pgmajfault"}, | |
14067bb3 KH |
4094 | {"inactive_anon", "total_inactive_anon"}, |
4095 | {"active_anon", "total_active_anon"}, | |
4096 | {"inactive_file", "total_inactive_file"}, | |
4097 | {"active_file", "total_active_file"}, | |
4098 | {"unevictable", "total_unevictable"} | |
4099 | }; | |
4100 | ||
4101 | ||
7d74b06f KH |
4102 | static void |
4103 | mem_cgroup_get_local_stat(struct mem_cgroup *mem, struct mcs_total_stat *s) | |
14067bb3 | 4104 | { |
14067bb3 KH |
4105 | s64 val; |
4106 | ||
4107 | /* per cpu stat */ | |
c62b1a3b | 4108 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_CACHE); |
14067bb3 | 4109 | s->stat[MCS_CACHE] += val * PAGE_SIZE; |
c62b1a3b | 4110 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_RSS); |
14067bb3 | 4111 | s->stat[MCS_RSS] += val * PAGE_SIZE; |
c62b1a3b | 4112 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_FILE_MAPPED); |
d8046582 | 4113 | s->stat[MCS_FILE_MAPPED] += val * PAGE_SIZE; |
e9f8974f | 4114 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGPGIN); |
14067bb3 | 4115 | s->stat[MCS_PGPGIN] += val; |
e9f8974f | 4116 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGPGOUT); |
14067bb3 | 4117 | s->stat[MCS_PGPGOUT] += val; |
1dd3a273 | 4118 | if (do_swap_account) { |
c62b1a3b | 4119 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_SWAPOUT); |
1dd3a273 DN |
4120 | s->stat[MCS_SWAP] += val * PAGE_SIZE; |
4121 | } | |
456f998e YH |
4122 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGFAULT); |
4123 | s->stat[MCS_PGFAULT] += val; | |
4124 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGMAJFAULT); | |
4125 | s->stat[MCS_PGMAJFAULT] += val; | |
14067bb3 KH |
4126 | |
4127 | /* per zone stat */ | |
bb2a0de9 | 4128 | val = mem_cgroup_nr_lru_pages(mem, BIT(LRU_INACTIVE_ANON)); |
14067bb3 | 4129 | s->stat[MCS_INACTIVE_ANON] += val * PAGE_SIZE; |
bb2a0de9 | 4130 | val = mem_cgroup_nr_lru_pages(mem, BIT(LRU_ACTIVE_ANON)); |
14067bb3 | 4131 | s->stat[MCS_ACTIVE_ANON] += val * PAGE_SIZE; |
bb2a0de9 | 4132 | val = mem_cgroup_nr_lru_pages(mem, BIT(LRU_INACTIVE_FILE)); |
14067bb3 | 4133 | s->stat[MCS_INACTIVE_FILE] += val * PAGE_SIZE; |
bb2a0de9 | 4134 | val = mem_cgroup_nr_lru_pages(mem, BIT(LRU_ACTIVE_FILE)); |
14067bb3 | 4135 | s->stat[MCS_ACTIVE_FILE] += val * PAGE_SIZE; |
bb2a0de9 | 4136 | val = mem_cgroup_nr_lru_pages(mem, BIT(LRU_UNEVICTABLE)); |
14067bb3 | 4137 | s->stat[MCS_UNEVICTABLE] += val * PAGE_SIZE; |
14067bb3 KH |
4138 | } |
4139 | ||
4140 | static void | |
4141 | mem_cgroup_get_total_stat(struct mem_cgroup *mem, struct mcs_total_stat *s) | |
4142 | { | |
7d74b06f KH |
4143 | struct mem_cgroup *iter; |
4144 | ||
4145 | for_each_mem_cgroup_tree(iter, mem) | |
4146 | mem_cgroup_get_local_stat(iter, s); | |
14067bb3 KH |
4147 | } |
4148 | ||
406eb0c9 YH |
4149 | #ifdef CONFIG_NUMA |
4150 | static int mem_control_numa_stat_show(struct seq_file *m, void *arg) | |
4151 | { | |
4152 | int nid; | |
4153 | unsigned long total_nr, file_nr, anon_nr, unevictable_nr; | |
4154 | unsigned long node_nr; | |
4155 | struct cgroup *cont = m->private; | |
4156 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); | |
4157 | ||
bb2a0de9 | 4158 | total_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL); |
406eb0c9 YH |
4159 | seq_printf(m, "total=%lu", total_nr); |
4160 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 | 4161 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, LRU_ALL); |
406eb0c9 YH |
4162 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4163 | } | |
4164 | seq_putc(m, '\n'); | |
4165 | ||
bb2a0de9 | 4166 | file_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL_FILE); |
406eb0c9 YH |
4167 | seq_printf(m, "file=%lu", file_nr); |
4168 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4169 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4170 | LRU_ALL_FILE); | |
406eb0c9 YH |
4171 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4172 | } | |
4173 | seq_putc(m, '\n'); | |
4174 | ||
bb2a0de9 | 4175 | anon_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL_ANON); |
406eb0c9 YH |
4176 | seq_printf(m, "anon=%lu", anon_nr); |
4177 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4178 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4179 | LRU_ALL_ANON); | |
406eb0c9 YH |
4180 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4181 | } | |
4182 | seq_putc(m, '\n'); | |
4183 | ||
bb2a0de9 | 4184 | unevictable_nr = mem_cgroup_nr_lru_pages(mem_cont, BIT(LRU_UNEVICTABLE)); |
406eb0c9 YH |
4185 | seq_printf(m, "unevictable=%lu", unevictable_nr); |
4186 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
bb2a0de9 KH |
4187 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, |
4188 | BIT(LRU_UNEVICTABLE)); | |
406eb0c9 YH |
4189 | seq_printf(m, " N%d=%lu", nid, node_nr); |
4190 | } | |
4191 | seq_putc(m, '\n'); | |
4192 | return 0; | |
4193 | } | |
4194 | #endif /* CONFIG_NUMA */ | |
4195 | ||
c64745cf PM |
4196 | static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, |
4197 | struct cgroup_map_cb *cb) | |
d2ceb9b7 | 4198 | { |
d2ceb9b7 | 4199 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); |
14067bb3 | 4200 | struct mcs_total_stat mystat; |
d2ceb9b7 KH |
4201 | int i; |
4202 | ||
14067bb3 KH |
4203 | memset(&mystat, 0, sizeof(mystat)); |
4204 | mem_cgroup_get_local_stat(mem_cont, &mystat); | |
d2ceb9b7 | 4205 | |
406eb0c9 | 4206 | |
1dd3a273 DN |
4207 | for (i = 0; i < NR_MCS_STAT; i++) { |
4208 | if (i == MCS_SWAP && !do_swap_account) | |
4209 | continue; | |
14067bb3 | 4210 | cb->fill(cb, memcg_stat_strings[i].local_name, mystat.stat[i]); |
1dd3a273 | 4211 | } |
7b854121 | 4212 | |
14067bb3 | 4213 | /* Hierarchical information */ |
fee7b548 KH |
4214 | { |
4215 | unsigned long long limit, memsw_limit; | |
4216 | memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit); | |
4217 | cb->fill(cb, "hierarchical_memory_limit", limit); | |
4218 | if (do_swap_account) | |
4219 | cb->fill(cb, "hierarchical_memsw_limit", memsw_limit); | |
4220 | } | |
7f016ee8 | 4221 | |
14067bb3 KH |
4222 | memset(&mystat, 0, sizeof(mystat)); |
4223 | mem_cgroup_get_total_stat(mem_cont, &mystat); | |
1dd3a273 DN |
4224 | for (i = 0; i < NR_MCS_STAT; i++) { |
4225 | if (i == MCS_SWAP && !do_swap_account) | |
4226 | continue; | |
14067bb3 | 4227 | cb->fill(cb, memcg_stat_strings[i].total_name, mystat.stat[i]); |
1dd3a273 | 4228 | } |
14067bb3 | 4229 | |
7f016ee8 | 4230 | #ifdef CONFIG_DEBUG_VM |
c772be93 | 4231 | cb->fill(cb, "inactive_ratio", calc_inactive_ratio(mem_cont, NULL)); |
7f016ee8 KM |
4232 | |
4233 | { | |
4234 | int nid, zid; | |
4235 | struct mem_cgroup_per_zone *mz; | |
4236 | unsigned long recent_rotated[2] = {0, 0}; | |
4237 | unsigned long recent_scanned[2] = {0, 0}; | |
4238 | ||
4239 | for_each_online_node(nid) | |
4240 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
4241 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); | |
4242 | ||
4243 | recent_rotated[0] += | |
4244 | mz->reclaim_stat.recent_rotated[0]; | |
4245 | recent_rotated[1] += | |
4246 | mz->reclaim_stat.recent_rotated[1]; | |
4247 | recent_scanned[0] += | |
4248 | mz->reclaim_stat.recent_scanned[0]; | |
4249 | recent_scanned[1] += | |
4250 | mz->reclaim_stat.recent_scanned[1]; | |
4251 | } | |
4252 | cb->fill(cb, "recent_rotated_anon", recent_rotated[0]); | |
4253 | cb->fill(cb, "recent_rotated_file", recent_rotated[1]); | |
4254 | cb->fill(cb, "recent_scanned_anon", recent_scanned[0]); | |
4255 | cb->fill(cb, "recent_scanned_file", recent_scanned[1]); | |
4256 | } | |
4257 | #endif | |
4258 | ||
d2ceb9b7 KH |
4259 | return 0; |
4260 | } | |
4261 | ||
a7885eb8 KM |
4262 | static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft) |
4263 | { | |
4264 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4265 | ||
1f4c025b | 4266 | return mem_cgroup_swappiness(memcg); |
a7885eb8 KM |
4267 | } |
4268 | ||
4269 | static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, | |
4270 | u64 val) | |
4271 | { | |
4272 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4273 | struct mem_cgroup *parent; | |
068b38c1 | 4274 | |
a7885eb8 KM |
4275 | if (val > 100) |
4276 | return -EINVAL; | |
4277 | ||
4278 | if (cgrp->parent == NULL) | |
4279 | return -EINVAL; | |
4280 | ||
4281 | parent = mem_cgroup_from_cont(cgrp->parent); | |
068b38c1 LZ |
4282 | |
4283 | cgroup_lock(); | |
4284 | ||
a7885eb8 KM |
4285 | /* If under hierarchy, only empty-root can set this value */ |
4286 | if ((parent->use_hierarchy) || | |
068b38c1 LZ |
4287 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
4288 | cgroup_unlock(); | |
a7885eb8 | 4289 | return -EINVAL; |
068b38c1 | 4290 | } |
a7885eb8 | 4291 | |
a7885eb8 | 4292 | memcg->swappiness = val; |
a7885eb8 | 4293 | |
068b38c1 LZ |
4294 | cgroup_unlock(); |
4295 | ||
a7885eb8 KM |
4296 | return 0; |
4297 | } | |
4298 | ||
2e72b634 KS |
4299 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
4300 | { | |
4301 | struct mem_cgroup_threshold_ary *t; | |
4302 | u64 usage; | |
4303 | int i; | |
4304 | ||
4305 | rcu_read_lock(); | |
4306 | if (!swap) | |
2c488db2 | 4307 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 4308 | else |
2c488db2 | 4309 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
4310 | |
4311 | if (!t) | |
4312 | goto unlock; | |
4313 | ||
4314 | usage = mem_cgroup_usage(memcg, swap); | |
4315 | ||
4316 | /* | |
4317 | * current_threshold points to threshold just below usage. | |
4318 | * If it's not true, a threshold was crossed after last | |
4319 | * call of __mem_cgroup_threshold(). | |
4320 | */ | |
5407a562 | 4321 | i = t->current_threshold; |
2e72b634 KS |
4322 | |
4323 | /* | |
4324 | * Iterate backward over array of thresholds starting from | |
4325 | * current_threshold and check if a threshold is crossed. | |
4326 | * If none of thresholds below usage is crossed, we read | |
4327 | * only one element of the array here. | |
4328 | */ | |
4329 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
4330 | eventfd_signal(t->entries[i].eventfd, 1); | |
4331 | ||
4332 | /* i = current_threshold + 1 */ | |
4333 | i++; | |
4334 | ||
4335 | /* | |
4336 | * Iterate forward over array of thresholds starting from | |
4337 | * current_threshold+1 and check if a threshold is crossed. | |
4338 | * If none of thresholds above usage is crossed, we read | |
4339 | * only one element of the array here. | |
4340 | */ | |
4341 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
4342 | eventfd_signal(t->entries[i].eventfd, 1); | |
4343 | ||
4344 | /* Update current_threshold */ | |
5407a562 | 4345 | t->current_threshold = i - 1; |
2e72b634 KS |
4346 | unlock: |
4347 | rcu_read_unlock(); | |
4348 | } | |
4349 | ||
4350 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
4351 | { | |
ad4ca5f4 KS |
4352 | while (memcg) { |
4353 | __mem_cgroup_threshold(memcg, false); | |
4354 | if (do_swap_account) | |
4355 | __mem_cgroup_threshold(memcg, true); | |
4356 | ||
4357 | memcg = parent_mem_cgroup(memcg); | |
4358 | } | |
2e72b634 KS |
4359 | } |
4360 | ||
4361 | static int compare_thresholds(const void *a, const void *b) | |
4362 | { | |
4363 | const struct mem_cgroup_threshold *_a = a; | |
4364 | const struct mem_cgroup_threshold *_b = b; | |
4365 | ||
4366 | return _a->threshold - _b->threshold; | |
4367 | } | |
4368 | ||
7d74b06f | 4369 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *mem) |
9490ff27 KH |
4370 | { |
4371 | struct mem_cgroup_eventfd_list *ev; | |
4372 | ||
4373 | list_for_each_entry(ev, &mem->oom_notify, list) | |
4374 | eventfd_signal(ev->eventfd, 1); | |
4375 | return 0; | |
4376 | } | |
4377 | ||
4378 | static void mem_cgroup_oom_notify(struct mem_cgroup *mem) | |
4379 | { | |
7d74b06f KH |
4380 | struct mem_cgroup *iter; |
4381 | ||
4382 | for_each_mem_cgroup_tree(iter, mem) | |
4383 | mem_cgroup_oom_notify_cb(iter); | |
9490ff27 KH |
4384 | } |
4385 | ||
4386 | static int mem_cgroup_usage_register_event(struct cgroup *cgrp, | |
4387 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
2e72b634 KS |
4388 | { |
4389 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4390 | struct mem_cgroup_thresholds *thresholds; |
4391 | struct mem_cgroup_threshold_ary *new; | |
2e72b634 KS |
4392 | int type = MEMFILE_TYPE(cft->private); |
4393 | u64 threshold, usage; | |
2c488db2 | 4394 | int i, size, ret; |
2e72b634 KS |
4395 | |
4396 | ret = res_counter_memparse_write_strategy(args, &threshold); | |
4397 | if (ret) | |
4398 | return ret; | |
4399 | ||
4400 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 4401 | |
2e72b634 | 4402 | if (type == _MEM) |
2c488db2 | 4403 | thresholds = &memcg->thresholds; |
2e72b634 | 4404 | else if (type == _MEMSWAP) |
2c488db2 | 4405 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4406 | else |
4407 | BUG(); | |
4408 | ||
4409 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4410 | ||
4411 | /* Check if a threshold crossed before adding a new one */ | |
2c488db2 | 4412 | if (thresholds->primary) |
2e72b634 KS |
4413 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4414 | ||
2c488db2 | 4415 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
4416 | |
4417 | /* Allocate memory for new array of thresholds */ | |
2c488db2 | 4418 | new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold), |
2e72b634 | 4419 | GFP_KERNEL); |
2c488db2 | 4420 | if (!new) { |
2e72b634 KS |
4421 | ret = -ENOMEM; |
4422 | goto unlock; | |
4423 | } | |
2c488db2 | 4424 | new->size = size; |
2e72b634 KS |
4425 | |
4426 | /* Copy thresholds (if any) to new array */ | |
2c488db2 KS |
4427 | if (thresholds->primary) { |
4428 | memcpy(new->entries, thresholds->primary->entries, (size - 1) * | |
2e72b634 | 4429 | sizeof(struct mem_cgroup_threshold)); |
2c488db2 KS |
4430 | } |
4431 | ||
2e72b634 | 4432 | /* Add new threshold */ |
2c488db2 KS |
4433 | new->entries[size - 1].eventfd = eventfd; |
4434 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
4435 | |
4436 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
2c488db2 | 4437 | sort(new->entries, size, sizeof(struct mem_cgroup_threshold), |
2e72b634 KS |
4438 | compare_thresholds, NULL); |
4439 | ||
4440 | /* Find current threshold */ | |
2c488db2 | 4441 | new->current_threshold = -1; |
2e72b634 | 4442 | for (i = 0; i < size; i++) { |
2c488db2 | 4443 | if (new->entries[i].threshold < usage) { |
2e72b634 | 4444 | /* |
2c488db2 KS |
4445 | * new->current_threshold will not be used until |
4446 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
4447 | * it here. |
4448 | */ | |
2c488db2 | 4449 | ++new->current_threshold; |
2e72b634 KS |
4450 | } |
4451 | } | |
4452 | ||
2c488db2 KS |
4453 | /* Free old spare buffer and save old primary buffer as spare */ |
4454 | kfree(thresholds->spare); | |
4455 | thresholds->spare = thresholds->primary; | |
4456 | ||
4457 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4458 | |
907860ed | 4459 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4460 | synchronize_rcu(); |
4461 | ||
2e72b634 KS |
4462 | unlock: |
4463 | mutex_unlock(&memcg->thresholds_lock); | |
4464 | ||
4465 | return ret; | |
4466 | } | |
4467 | ||
907860ed | 4468 | static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp, |
9490ff27 | 4469 | struct cftype *cft, struct eventfd_ctx *eventfd) |
2e72b634 KS |
4470 | { |
4471 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4472 | struct mem_cgroup_thresholds *thresholds; |
4473 | struct mem_cgroup_threshold_ary *new; | |
2e72b634 KS |
4474 | int type = MEMFILE_TYPE(cft->private); |
4475 | u64 usage; | |
2c488db2 | 4476 | int i, j, size; |
2e72b634 KS |
4477 | |
4478 | mutex_lock(&memcg->thresholds_lock); | |
4479 | if (type == _MEM) | |
2c488db2 | 4480 | thresholds = &memcg->thresholds; |
2e72b634 | 4481 | else if (type == _MEMSWAP) |
2c488db2 | 4482 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4483 | else |
4484 | BUG(); | |
4485 | ||
4486 | /* | |
4487 | * Something went wrong if we trying to unregister a threshold | |
4488 | * if we don't have thresholds | |
4489 | */ | |
4490 | BUG_ON(!thresholds); | |
4491 | ||
4492 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4493 | ||
4494 | /* Check if a threshold crossed before removing */ | |
4495 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
4496 | ||
4497 | /* Calculate new number of threshold */ | |
2c488db2 KS |
4498 | size = 0; |
4499 | for (i = 0; i < thresholds->primary->size; i++) { | |
4500 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 KS |
4501 | size++; |
4502 | } | |
4503 | ||
2c488db2 | 4504 | new = thresholds->spare; |
907860ed | 4505 | |
2e72b634 KS |
4506 | /* Set thresholds array to NULL if we don't have thresholds */ |
4507 | if (!size) { | |
2c488db2 KS |
4508 | kfree(new); |
4509 | new = NULL; | |
907860ed | 4510 | goto swap_buffers; |
2e72b634 KS |
4511 | } |
4512 | ||
2c488db2 | 4513 | new->size = size; |
2e72b634 KS |
4514 | |
4515 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
4516 | new->current_threshold = -1; |
4517 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
4518 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
4519 | continue; |
4520 | ||
2c488db2 KS |
4521 | new->entries[j] = thresholds->primary->entries[i]; |
4522 | if (new->entries[j].threshold < usage) { | |
2e72b634 | 4523 | /* |
2c488db2 | 4524 | * new->current_threshold will not be used |
2e72b634 KS |
4525 | * until rcu_assign_pointer(), so it's safe to increment |
4526 | * it here. | |
4527 | */ | |
2c488db2 | 4528 | ++new->current_threshold; |
2e72b634 KS |
4529 | } |
4530 | j++; | |
4531 | } | |
4532 | ||
907860ed | 4533 | swap_buffers: |
2c488db2 KS |
4534 | /* Swap primary and spare array */ |
4535 | thresholds->spare = thresholds->primary; | |
4536 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4537 | |
907860ed | 4538 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4539 | synchronize_rcu(); |
4540 | ||
2e72b634 | 4541 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 4542 | } |
c1e862c1 | 4543 | |
9490ff27 KH |
4544 | static int mem_cgroup_oom_register_event(struct cgroup *cgrp, |
4545 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
4546 | { | |
4547 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4548 | struct mem_cgroup_eventfd_list *event; | |
4549 | int type = MEMFILE_TYPE(cft->private); | |
4550 | ||
4551 | BUG_ON(type != _OOM_TYPE); | |
4552 | event = kmalloc(sizeof(*event), GFP_KERNEL); | |
4553 | if (!event) | |
4554 | return -ENOMEM; | |
4555 | ||
1af8efe9 | 4556 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4557 | |
4558 | event->eventfd = eventfd; | |
4559 | list_add(&event->list, &memcg->oom_notify); | |
4560 | ||
4561 | /* already in OOM ? */ | |
79dfdacc | 4562 | if (atomic_read(&memcg->under_oom)) |
9490ff27 | 4563 | eventfd_signal(eventfd, 1); |
1af8efe9 | 4564 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4565 | |
4566 | return 0; | |
4567 | } | |
4568 | ||
907860ed | 4569 | static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp, |
9490ff27 KH |
4570 | struct cftype *cft, struct eventfd_ctx *eventfd) |
4571 | { | |
4572 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4573 | struct mem_cgroup_eventfd_list *ev, *tmp; | |
4574 | int type = MEMFILE_TYPE(cft->private); | |
4575 | ||
4576 | BUG_ON(type != _OOM_TYPE); | |
4577 | ||
1af8efe9 | 4578 | spin_lock(&memcg_oom_lock); |
9490ff27 KH |
4579 | |
4580 | list_for_each_entry_safe(ev, tmp, &mem->oom_notify, list) { | |
4581 | if (ev->eventfd == eventfd) { | |
4582 | list_del(&ev->list); | |
4583 | kfree(ev); | |
4584 | } | |
4585 | } | |
4586 | ||
1af8efe9 | 4587 | spin_unlock(&memcg_oom_lock); |
9490ff27 KH |
4588 | } |
4589 | ||
3c11ecf4 KH |
4590 | static int mem_cgroup_oom_control_read(struct cgroup *cgrp, |
4591 | struct cftype *cft, struct cgroup_map_cb *cb) | |
4592 | { | |
4593 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4594 | ||
4595 | cb->fill(cb, "oom_kill_disable", mem->oom_kill_disable); | |
4596 | ||
79dfdacc | 4597 | if (atomic_read(&mem->under_oom)) |
3c11ecf4 KH |
4598 | cb->fill(cb, "under_oom", 1); |
4599 | else | |
4600 | cb->fill(cb, "under_oom", 0); | |
4601 | return 0; | |
4602 | } | |
4603 | ||
3c11ecf4 KH |
4604 | static int mem_cgroup_oom_control_write(struct cgroup *cgrp, |
4605 | struct cftype *cft, u64 val) | |
4606 | { | |
4607 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4608 | struct mem_cgroup *parent; | |
4609 | ||
4610 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
4611 | if (!cgrp->parent || !((val == 0) || (val == 1))) | |
4612 | return -EINVAL; | |
4613 | ||
4614 | parent = mem_cgroup_from_cont(cgrp->parent); | |
4615 | ||
4616 | cgroup_lock(); | |
4617 | /* oom-kill-disable is a flag for subhierarchy. */ | |
4618 | if ((parent->use_hierarchy) || | |
4619 | (mem->use_hierarchy && !list_empty(&cgrp->children))) { | |
4620 | cgroup_unlock(); | |
4621 | return -EINVAL; | |
4622 | } | |
4623 | mem->oom_kill_disable = val; | |
4d845ebf KH |
4624 | if (!val) |
4625 | memcg_oom_recover(mem); | |
3c11ecf4 KH |
4626 | cgroup_unlock(); |
4627 | return 0; | |
4628 | } | |
4629 | ||
406eb0c9 YH |
4630 | #ifdef CONFIG_NUMA |
4631 | static const struct file_operations mem_control_numa_stat_file_operations = { | |
4632 | .read = seq_read, | |
4633 | .llseek = seq_lseek, | |
4634 | .release = single_release, | |
4635 | }; | |
4636 | ||
4637 | static int mem_control_numa_stat_open(struct inode *unused, struct file *file) | |
4638 | { | |
4639 | struct cgroup *cont = file->f_dentry->d_parent->d_fsdata; | |
4640 | ||
4641 | file->f_op = &mem_control_numa_stat_file_operations; | |
4642 | return single_open(file, mem_control_numa_stat_show, cont); | |
4643 | } | |
4644 | #endif /* CONFIG_NUMA */ | |
4645 | ||
8cdea7c0 BS |
4646 | static struct cftype mem_cgroup_files[] = { |
4647 | { | |
0eea1030 | 4648 | .name = "usage_in_bytes", |
8c7c6e34 | 4649 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
2c3daa72 | 4650 | .read_u64 = mem_cgroup_read, |
9490ff27 KH |
4651 | .register_event = mem_cgroup_usage_register_event, |
4652 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8cdea7c0 | 4653 | }, |
c84872e1 PE |
4654 | { |
4655 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 4656 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
29f2a4da | 4657 | .trigger = mem_cgroup_reset, |
c84872e1 PE |
4658 | .read_u64 = mem_cgroup_read, |
4659 | }, | |
8cdea7c0 | 4660 | { |
0eea1030 | 4661 | .name = "limit_in_bytes", |
8c7c6e34 | 4662 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
856c13aa | 4663 | .write_string = mem_cgroup_write, |
2c3daa72 | 4664 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 4665 | }, |
296c81d8 BS |
4666 | { |
4667 | .name = "soft_limit_in_bytes", | |
4668 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
4669 | .write_string = mem_cgroup_write, | |
4670 | .read_u64 = mem_cgroup_read, | |
4671 | }, | |
8cdea7c0 BS |
4672 | { |
4673 | .name = "failcnt", | |
8c7c6e34 | 4674 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
29f2a4da | 4675 | .trigger = mem_cgroup_reset, |
2c3daa72 | 4676 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 4677 | }, |
d2ceb9b7 KH |
4678 | { |
4679 | .name = "stat", | |
c64745cf | 4680 | .read_map = mem_control_stat_show, |
d2ceb9b7 | 4681 | }, |
c1e862c1 KH |
4682 | { |
4683 | .name = "force_empty", | |
4684 | .trigger = mem_cgroup_force_empty_write, | |
4685 | }, | |
18f59ea7 BS |
4686 | { |
4687 | .name = "use_hierarchy", | |
4688 | .write_u64 = mem_cgroup_hierarchy_write, | |
4689 | .read_u64 = mem_cgroup_hierarchy_read, | |
4690 | }, | |
a7885eb8 KM |
4691 | { |
4692 | .name = "swappiness", | |
4693 | .read_u64 = mem_cgroup_swappiness_read, | |
4694 | .write_u64 = mem_cgroup_swappiness_write, | |
4695 | }, | |
7dc74be0 DN |
4696 | { |
4697 | .name = "move_charge_at_immigrate", | |
4698 | .read_u64 = mem_cgroup_move_charge_read, | |
4699 | .write_u64 = mem_cgroup_move_charge_write, | |
4700 | }, | |
9490ff27 KH |
4701 | { |
4702 | .name = "oom_control", | |
3c11ecf4 KH |
4703 | .read_map = mem_cgroup_oom_control_read, |
4704 | .write_u64 = mem_cgroup_oom_control_write, | |
9490ff27 KH |
4705 | .register_event = mem_cgroup_oom_register_event, |
4706 | .unregister_event = mem_cgroup_oom_unregister_event, | |
4707 | .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), | |
4708 | }, | |
406eb0c9 YH |
4709 | #ifdef CONFIG_NUMA |
4710 | { | |
4711 | .name = "numa_stat", | |
4712 | .open = mem_control_numa_stat_open, | |
89577127 | 4713 | .mode = S_IRUGO, |
406eb0c9 YH |
4714 | }, |
4715 | #endif | |
8cdea7c0 BS |
4716 | }; |
4717 | ||
8c7c6e34 KH |
4718 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4719 | static struct cftype memsw_cgroup_files[] = { | |
4720 | { | |
4721 | .name = "memsw.usage_in_bytes", | |
4722 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
4723 | .read_u64 = mem_cgroup_read, | |
9490ff27 KH |
4724 | .register_event = mem_cgroup_usage_register_event, |
4725 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8c7c6e34 KH |
4726 | }, |
4727 | { | |
4728 | .name = "memsw.max_usage_in_bytes", | |
4729 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
4730 | .trigger = mem_cgroup_reset, | |
4731 | .read_u64 = mem_cgroup_read, | |
4732 | }, | |
4733 | { | |
4734 | .name = "memsw.limit_in_bytes", | |
4735 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
4736 | .write_string = mem_cgroup_write, | |
4737 | .read_u64 = mem_cgroup_read, | |
4738 | }, | |
4739 | { | |
4740 | .name = "memsw.failcnt", | |
4741 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
4742 | .trigger = mem_cgroup_reset, | |
4743 | .read_u64 = mem_cgroup_read, | |
4744 | }, | |
4745 | }; | |
4746 | ||
4747 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4748 | { | |
4749 | if (!do_swap_account) | |
4750 | return 0; | |
4751 | return cgroup_add_files(cont, ss, memsw_cgroup_files, | |
4752 | ARRAY_SIZE(memsw_cgroup_files)); | |
4753 | }; | |
4754 | #else | |
4755 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4756 | { | |
4757 | return 0; | |
4758 | } | |
4759 | #endif | |
4760 | ||
6d12e2d8 KH |
4761 | static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
4762 | { | |
4763 | struct mem_cgroup_per_node *pn; | |
1ecaab2b | 4764 | struct mem_cgroup_per_zone *mz; |
b69408e8 | 4765 | enum lru_list l; |
41e3355d | 4766 | int zone, tmp = node; |
1ecaab2b KH |
4767 | /* |
4768 | * This routine is called against possible nodes. | |
4769 | * But it's BUG to call kmalloc() against offline node. | |
4770 | * | |
4771 | * TODO: this routine can waste much memory for nodes which will | |
4772 | * never be onlined. It's better to use memory hotplug callback | |
4773 | * function. | |
4774 | */ | |
41e3355d KH |
4775 | if (!node_state(node, N_NORMAL_MEMORY)) |
4776 | tmp = -1; | |
17295c88 | 4777 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); |
6d12e2d8 KH |
4778 | if (!pn) |
4779 | return 1; | |
1ecaab2b | 4780 | |
6d12e2d8 | 4781 | mem->info.nodeinfo[node] = pn; |
1ecaab2b KH |
4782 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
4783 | mz = &pn->zoneinfo[zone]; | |
b69408e8 CL |
4784 | for_each_lru(l) |
4785 | INIT_LIST_HEAD(&mz->lists[l]); | |
f64c3f54 | 4786 | mz->usage_in_excess = 0; |
4e416953 BS |
4787 | mz->on_tree = false; |
4788 | mz->mem = mem; | |
1ecaab2b | 4789 | } |
6d12e2d8 KH |
4790 | return 0; |
4791 | } | |
4792 | ||
1ecaab2b KH |
4793 | static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
4794 | { | |
4795 | kfree(mem->info.nodeinfo[node]); | |
4796 | } | |
4797 | ||
33327948 KH |
4798 | static struct mem_cgroup *mem_cgroup_alloc(void) |
4799 | { | |
4800 | struct mem_cgroup *mem; | |
c62b1a3b | 4801 | int size = sizeof(struct mem_cgroup); |
33327948 | 4802 | |
c62b1a3b | 4803 | /* Can be very big if MAX_NUMNODES is very big */ |
c8dad2bb | 4804 | if (size < PAGE_SIZE) |
17295c88 | 4805 | mem = kzalloc(size, GFP_KERNEL); |
33327948 | 4806 | else |
17295c88 | 4807 | mem = vzalloc(size); |
33327948 | 4808 | |
e7bbcdf3 DC |
4809 | if (!mem) |
4810 | return NULL; | |
4811 | ||
c62b1a3b | 4812 | mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu); |
d2e61b8d DC |
4813 | if (!mem->stat) |
4814 | goto out_free; | |
711d3d2c | 4815 | spin_lock_init(&mem->pcp_counter_lock); |
33327948 | 4816 | return mem; |
d2e61b8d DC |
4817 | |
4818 | out_free: | |
4819 | if (size < PAGE_SIZE) | |
4820 | kfree(mem); | |
4821 | else | |
4822 | vfree(mem); | |
4823 | return NULL; | |
33327948 KH |
4824 | } |
4825 | ||
8c7c6e34 KH |
4826 | /* |
4827 | * At destroying mem_cgroup, references from swap_cgroup can remain. | |
4828 | * (scanning all at force_empty is too costly...) | |
4829 | * | |
4830 | * Instead of clearing all references at force_empty, we remember | |
4831 | * the number of reference from swap_cgroup and free mem_cgroup when | |
4832 | * it goes down to 0. | |
4833 | * | |
8c7c6e34 KH |
4834 | * Removal of cgroup itself succeeds regardless of refs from swap. |
4835 | */ | |
4836 | ||
a7ba0eef | 4837 | static void __mem_cgroup_free(struct mem_cgroup *mem) |
33327948 | 4838 | { |
08e552c6 KH |
4839 | int node; |
4840 | ||
f64c3f54 | 4841 | mem_cgroup_remove_from_trees(mem); |
04046e1a KH |
4842 | free_css_id(&mem_cgroup_subsys, &mem->css); |
4843 | ||
08e552c6 KH |
4844 | for_each_node_state(node, N_POSSIBLE) |
4845 | free_mem_cgroup_per_zone_info(mem, node); | |
4846 | ||
c62b1a3b KH |
4847 | free_percpu(mem->stat); |
4848 | if (sizeof(struct mem_cgroup) < PAGE_SIZE) | |
33327948 KH |
4849 | kfree(mem); |
4850 | else | |
4851 | vfree(mem); | |
4852 | } | |
4853 | ||
8c7c6e34 KH |
4854 | static void mem_cgroup_get(struct mem_cgroup *mem) |
4855 | { | |
4856 | atomic_inc(&mem->refcnt); | |
4857 | } | |
4858 | ||
483c30b5 | 4859 | static void __mem_cgroup_put(struct mem_cgroup *mem, int count) |
8c7c6e34 | 4860 | { |
483c30b5 | 4861 | if (atomic_sub_and_test(count, &mem->refcnt)) { |
7bcc1bb1 | 4862 | struct mem_cgroup *parent = parent_mem_cgroup(mem); |
a7ba0eef | 4863 | __mem_cgroup_free(mem); |
7bcc1bb1 DN |
4864 | if (parent) |
4865 | mem_cgroup_put(parent); | |
4866 | } | |
8c7c6e34 KH |
4867 | } |
4868 | ||
483c30b5 DN |
4869 | static void mem_cgroup_put(struct mem_cgroup *mem) |
4870 | { | |
4871 | __mem_cgroup_put(mem, 1); | |
4872 | } | |
4873 | ||
7bcc1bb1 DN |
4874 | /* |
4875 | * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. | |
4876 | */ | |
4877 | static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem) | |
4878 | { | |
4879 | if (!mem->res.parent) | |
4880 | return NULL; | |
4881 | return mem_cgroup_from_res_counter(mem->res.parent, res); | |
4882 | } | |
33327948 | 4883 | |
c077719b KH |
4884 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4885 | static void __init enable_swap_cgroup(void) | |
4886 | { | |
f8d66542 | 4887 | if (!mem_cgroup_disabled() && really_do_swap_account) |
c077719b KH |
4888 | do_swap_account = 1; |
4889 | } | |
4890 | #else | |
4891 | static void __init enable_swap_cgroup(void) | |
4892 | { | |
4893 | } | |
4894 | #endif | |
4895 | ||
f64c3f54 BS |
4896 | static int mem_cgroup_soft_limit_tree_init(void) |
4897 | { | |
4898 | struct mem_cgroup_tree_per_node *rtpn; | |
4899 | struct mem_cgroup_tree_per_zone *rtpz; | |
4900 | int tmp, node, zone; | |
4901 | ||
4902 | for_each_node_state(node, N_POSSIBLE) { | |
4903 | tmp = node; | |
4904 | if (!node_state(node, N_NORMAL_MEMORY)) | |
4905 | tmp = -1; | |
4906 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, tmp); | |
4907 | if (!rtpn) | |
4908 | return 1; | |
4909 | ||
4910 | soft_limit_tree.rb_tree_per_node[node] = rtpn; | |
4911 | ||
4912 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
4913 | rtpz = &rtpn->rb_tree_per_zone[zone]; | |
4914 | rtpz->rb_root = RB_ROOT; | |
4915 | spin_lock_init(&rtpz->lock); | |
4916 | } | |
4917 | } | |
4918 | return 0; | |
4919 | } | |
4920 | ||
0eb253e2 | 4921 | static struct cgroup_subsys_state * __ref |
8cdea7c0 BS |
4922 | mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) |
4923 | { | |
28dbc4b6 | 4924 | struct mem_cgroup *mem, *parent; |
04046e1a | 4925 | long error = -ENOMEM; |
6d12e2d8 | 4926 | int node; |
8cdea7c0 | 4927 | |
c8dad2bb JB |
4928 | mem = mem_cgroup_alloc(); |
4929 | if (!mem) | |
04046e1a | 4930 | return ERR_PTR(error); |
78fb7466 | 4931 | |
6d12e2d8 KH |
4932 | for_each_node_state(node, N_POSSIBLE) |
4933 | if (alloc_mem_cgroup_per_zone_info(mem, node)) | |
4934 | goto free_out; | |
f64c3f54 | 4935 | |
c077719b | 4936 | /* root ? */ |
28dbc4b6 | 4937 | if (cont->parent == NULL) { |
cdec2e42 | 4938 | int cpu; |
c077719b | 4939 | enable_swap_cgroup(); |
28dbc4b6 | 4940 | parent = NULL; |
4b3bde4c | 4941 | root_mem_cgroup = mem; |
f64c3f54 BS |
4942 | if (mem_cgroup_soft_limit_tree_init()) |
4943 | goto free_out; | |
cdec2e42 KH |
4944 | for_each_possible_cpu(cpu) { |
4945 | struct memcg_stock_pcp *stock = | |
4946 | &per_cpu(memcg_stock, cpu); | |
4947 | INIT_WORK(&stock->work, drain_local_stock); | |
4948 | } | |
711d3d2c | 4949 | hotcpu_notifier(memcg_cpu_hotplug_callback, 0); |
18f59ea7 | 4950 | } else { |
28dbc4b6 | 4951 | parent = mem_cgroup_from_cont(cont->parent); |
18f59ea7 | 4952 | mem->use_hierarchy = parent->use_hierarchy; |
3c11ecf4 | 4953 | mem->oom_kill_disable = parent->oom_kill_disable; |
18f59ea7 | 4954 | } |
28dbc4b6 | 4955 | |
18f59ea7 BS |
4956 | if (parent && parent->use_hierarchy) { |
4957 | res_counter_init(&mem->res, &parent->res); | |
4958 | res_counter_init(&mem->memsw, &parent->memsw); | |
7bcc1bb1 DN |
4959 | /* |
4960 | * We increment refcnt of the parent to ensure that we can | |
4961 | * safely access it on res_counter_charge/uncharge. | |
4962 | * This refcnt will be decremented when freeing this | |
4963 | * mem_cgroup(see mem_cgroup_put). | |
4964 | */ | |
4965 | mem_cgroup_get(parent); | |
18f59ea7 BS |
4966 | } else { |
4967 | res_counter_init(&mem->res, NULL); | |
4968 | res_counter_init(&mem->memsw, NULL); | |
4969 | } | |
04046e1a | 4970 | mem->last_scanned_child = 0; |
889976db | 4971 | mem->last_scanned_node = MAX_NUMNODES; |
9490ff27 | 4972 | INIT_LIST_HEAD(&mem->oom_notify); |
6d61ef40 | 4973 | |
a7885eb8 | 4974 | if (parent) |
1f4c025b | 4975 | mem->swappiness = mem_cgroup_swappiness(parent); |
a7ba0eef | 4976 | atomic_set(&mem->refcnt, 1); |
7dc74be0 | 4977 | mem->move_charge_at_immigrate = 0; |
2e72b634 | 4978 | mutex_init(&mem->thresholds_lock); |
8cdea7c0 | 4979 | return &mem->css; |
6d12e2d8 | 4980 | free_out: |
a7ba0eef | 4981 | __mem_cgroup_free(mem); |
4b3bde4c | 4982 | root_mem_cgroup = NULL; |
04046e1a | 4983 | return ERR_PTR(error); |
8cdea7c0 BS |
4984 | } |
4985 | ||
ec64f515 | 4986 | static int mem_cgroup_pre_destroy(struct cgroup_subsys *ss, |
df878fb0 KH |
4987 | struct cgroup *cont) |
4988 | { | |
4989 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); | |
ec64f515 KH |
4990 | |
4991 | return mem_cgroup_force_empty(mem, false); | |
df878fb0 KH |
4992 | } |
4993 | ||
8cdea7c0 BS |
4994 | static void mem_cgroup_destroy(struct cgroup_subsys *ss, |
4995 | struct cgroup *cont) | |
4996 | { | |
c268e994 | 4997 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
c268e994 | 4998 | |
c268e994 | 4999 | mem_cgroup_put(mem); |
8cdea7c0 BS |
5000 | } |
5001 | ||
5002 | static int mem_cgroup_populate(struct cgroup_subsys *ss, | |
5003 | struct cgroup *cont) | |
5004 | { | |
8c7c6e34 KH |
5005 | int ret; |
5006 | ||
5007 | ret = cgroup_add_files(cont, ss, mem_cgroup_files, | |
5008 | ARRAY_SIZE(mem_cgroup_files)); | |
5009 | ||
5010 | if (!ret) | |
5011 | ret = register_memsw_files(cont, ss); | |
5012 | return ret; | |
8cdea7c0 BS |
5013 | } |
5014 | ||
02491447 | 5015 | #ifdef CONFIG_MMU |
7dc74be0 | 5016 | /* Handlers for move charge at task migration. */ |
854ffa8d DN |
5017 | #define PRECHARGE_COUNT_AT_ONCE 256 |
5018 | static int mem_cgroup_do_precharge(unsigned long count) | |
7dc74be0 | 5019 | { |
854ffa8d DN |
5020 | int ret = 0; |
5021 | int batch_count = PRECHARGE_COUNT_AT_ONCE; | |
4ffef5fe DN |
5022 | struct mem_cgroup *mem = mc.to; |
5023 | ||
854ffa8d DN |
5024 | if (mem_cgroup_is_root(mem)) { |
5025 | mc.precharge += count; | |
5026 | /* we don't need css_get for root */ | |
5027 | return ret; | |
5028 | } | |
5029 | /* try to charge at once */ | |
5030 | if (count > 1) { | |
5031 | struct res_counter *dummy; | |
5032 | /* | |
5033 | * "mem" cannot be under rmdir() because we've already checked | |
5034 | * by cgroup_lock_live_cgroup() that it is not removed and we | |
5035 | * are still under the same cgroup_mutex. So we can postpone | |
5036 | * css_get(). | |
5037 | */ | |
5038 | if (res_counter_charge(&mem->res, PAGE_SIZE * count, &dummy)) | |
5039 | goto one_by_one; | |
5040 | if (do_swap_account && res_counter_charge(&mem->memsw, | |
5041 | PAGE_SIZE * count, &dummy)) { | |
5042 | res_counter_uncharge(&mem->res, PAGE_SIZE * count); | |
5043 | goto one_by_one; | |
5044 | } | |
5045 | mc.precharge += count; | |
854ffa8d DN |
5046 | return ret; |
5047 | } | |
5048 | one_by_one: | |
5049 | /* fall back to one by one charge */ | |
5050 | while (count--) { | |
5051 | if (signal_pending(current)) { | |
5052 | ret = -EINTR; | |
5053 | break; | |
5054 | } | |
5055 | if (!batch_count--) { | |
5056 | batch_count = PRECHARGE_COUNT_AT_ONCE; | |
5057 | cond_resched(); | |
5058 | } | |
7ec99d62 | 5059 | ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, 1, &mem, false); |
854ffa8d DN |
5060 | if (ret || !mem) |
5061 | /* mem_cgroup_clear_mc() will do uncharge later */ | |
5062 | return -ENOMEM; | |
5063 | mc.precharge++; | |
5064 | } | |
4ffef5fe DN |
5065 | return ret; |
5066 | } | |
5067 | ||
5068 | /** | |
5069 | * is_target_pte_for_mc - check a pte whether it is valid for move charge | |
5070 | * @vma: the vma the pte to be checked belongs | |
5071 | * @addr: the address corresponding to the pte to be checked | |
5072 | * @ptent: the pte to be checked | |
02491447 | 5073 | * @target: the pointer the target page or swap ent will be stored(can be NULL) |
4ffef5fe DN |
5074 | * |
5075 | * Returns | |
5076 | * 0(MC_TARGET_NONE): if the pte is not a target for move charge. | |
5077 | * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for | |
5078 | * move charge. if @target is not NULL, the page is stored in target->page | |
5079 | * with extra refcnt got(Callers should handle it). | |
02491447 DN |
5080 | * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a |
5081 | * target for charge migration. if @target is not NULL, the entry is stored | |
5082 | * in target->ent. | |
4ffef5fe DN |
5083 | * |
5084 | * Called with pte lock held. | |
5085 | */ | |
4ffef5fe DN |
5086 | union mc_target { |
5087 | struct page *page; | |
02491447 | 5088 | swp_entry_t ent; |
4ffef5fe DN |
5089 | }; |
5090 | ||
4ffef5fe DN |
5091 | enum mc_target_type { |
5092 | MC_TARGET_NONE, /* not used */ | |
5093 | MC_TARGET_PAGE, | |
02491447 | 5094 | MC_TARGET_SWAP, |
4ffef5fe DN |
5095 | }; |
5096 | ||
90254a65 DN |
5097 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
5098 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 5099 | { |
90254a65 | 5100 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 5101 | |
90254a65 DN |
5102 | if (!page || !page_mapped(page)) |
5103 | return NULL; | |
5104 | if (PageAnon(page)) { | |
5105 | /* we don't move shared anon */ | |
5106 | if (!move_anon() || page_mapcount(page) > 2) | |
5107 | return NULL; | |
87946a72 DN |
5108 | } else if (!move_file()) |
5109 | /* we ignore mapcount for file pages */ | |
90254a65 DN |
5110 | return NULL; |
5111 | if (!get_page_unless_zero(page)) | |
5112 | return NULL; | |
5113 | ||
5114 | return page; | |
5115 | } | |
5116 | ||
5117 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
5118 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5119 | { | |
5120 | int usage_count; | |
5121 | struct page *page = NULL; | |
5122 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
5123 | ||
5124 | if (!move_anon() || non_swap_entry(ent)) | |
5125 | return NULL; | |
5126 | usage_count = mem_cgroup_count_swap_user(ent, &page); | |
5127 | if (usage_count > 1) { /* we don't move shared anon */ | |
02491447 DN |
5128 | if (page) |
5129 | put_page(page); | |
90254a65 | 5130 | return NULL; |
02491447 | 5131 | } |
90254a65 DN |
5132 | if (do_swap_account) |
5133 | entry->val = ent.val; | |
5134 | ||
5135 | return page; | |
5136 | } | |
5137 | ||
87946a72 DN |
5138 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
5139 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5140 | { | |
5141 | struct page *page = NULL; | |
5142 | struct inode *inode; | |
5143 | struct address_space *mapping; | |
5144 | pgoff_t pgoff; | |
5145 | ||
5146 | if (!vma->vm_file) /* anonymous vma */ | |
5147 | return NULL; | |
5148 | if (!move_file()) | |
5149 | return NULL; | |
5150 | ||
5151 | inode = vma->vm_file->f_path.dentry->d_inode; | |
5152 | mapping = vma->vm_file->f_mapping; | |
5153 | if (pte_none(ptent)) | |
5154 | pgoff = linear_page_index(vma, addr); | |
5155 | else /* pte_file(ptent) is true */ | |
5156 | pgoff = pte_to_pgoff(ptent); | |
5157 | ||
5158 | /* page is moved even if it's not RSS of this task(page-faulted). */ | |
5159 | if (!mapping_cap_swap_backed(mapping)) { /* normal file */ | |
5160 | page = find_get_page(mapping, pgoff); | |
5161 | } else { /* shmem/tmpfs file. we should take account of swap too. */ | |
5162 | swp_entry_t ent; | |
5163 | mem_cgroup_get_shmem_target(inode, pgoff, &page, &ent); | |
5164 | if (do_swap_account) | |
5165 | entry->val = ent.val; | |
5166 | } | |
5167 | ||
5168 | return page; | |
5169 | } | |
5170 | ||
90254a65 DN |
5171 | static int is_target_pte_for_mc(struct vm_area_struct *vma, |
5172 | unsigned long addr, pte_t ptent, union mc_target *target) | |
5173 | { | |
5174 | struct page *page = NULL; | |
5175 | struct page_cgroup *pc; | |
5176 | int ret = 0; | |
5177 | swp_entry_t ent = { .val = 0 }; | |
5178 | ||
5179 | if (pte_present(ptent)) | |
5180 | page = mc_handle_present_pte(vma, addr, ptent); | |
5181 | else if (is_swap_pte(ptent)) | |
5182 | page = mc_handle_swap_pte(vma, addr, ptent, &ent); | |
87946a72 DN |
5183 | else if (pte_none(ptent) || pte_file(ptent)) |
5184 | page = mc_handle_file_pte(vma, addr, ptent, &ent); | |
90254a65 DN |
5185 | |
5186 | if (!page && !ent.val) | |
5187 | return 0; | |
02491447 DN |
5188 | if (page) { |
5189 | pc = lookup_page_cgroup(page); | |
5190 | /* | |
5191 | * Do only loose check w/o page_cgroup lock. | |
5192 | * mem_cgroup_move_account() checks the pc is valid or not under | |
5193 | * the lock. | |
5194 | */ | |
5195 | if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { | |
5196 | ret = MC_TARGET_PAGE; | |
5197 | if (target) | |
5198 | target->page = page; | |
5199 | } | |
5200 | if (!ret || !target) | |
5201 | put_page(page); | |
5202 | } | |
90254a65 DN |
5203 | /* There is a swap entry and a page doesn't exist or isn't charged */ |
5204 | if (ent.val && !ret && | |
7f0f1546 KH |
5205 | css_id(&mc.from->css) == lookup_swap_cgroup(ent)) { |
5206 | ret = MC_TARGET_SWAP; | |
5207 | if (target) | |
5208 | target->ent = ent; | |
4ffef5fe | 5209 | } |
4ffef5fe DN |
5210 | return ret; |
5211 | } | |
5212 | ||
5213 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, | |
5214 | unsigned long addr, unsigned long end, | |
5215 | struct mm_walk *walk) | |
5216 | { | |
5217 | struct vm_area_struct *vma = walk->private; | |
5218 | pte_t *pte; | |
5219 | spinlock_t *ptl; | |
5220 | ||
03319327 DH |
5221 | split_huge_page_pmd(walk->mm, pmd); |
5222 | ||
4ffef5fe DN |
5223 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
5224 | for (; addr != end; pte++, addr += PAGE_SIZE) | |
5225 | if (is_target_pte_for_mc(vma, addr, *pte, NULL)) | |
5226 | mc.precharge++; /* increment precharge temporarily */ | |
5227 | pte_unmap_unlock(pte - 1, ptl); | |
5228 | cond_resched(); | |
5229 | ||
7dc74be0 DN |
5230 | return 0; |
5231 | } | |
5232 | ||
4ffef5fe DN |
5233 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
5234 | { | |
5235 | unsigned long precharge; | |
5236 | struct vm_area_struct *vma; | |
5237 | ||
dfe076b0 | 5238 | down_read(&mm->mmap_sem); |
4ffef5fe DN |
5239 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5240 | struct mm_walk mem_cgroup_count_precharge_walk = { | |
5241 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
5242 | .mm = mm, | |
5243 | .private = vma, | |
5244 | }; | |
5245 | if (is_vm_hugetlb_page(vma)) | |
5246 | continue; | |
4ffef5fe DN |
5247 | walk_page_range(vma->vm_start, vma->vm_end, |
5248 | &mem_cgroup_count_precharge_walk); | |
5249 | } | |
dfe076b0 | 5250 | up_read(&mm->mmap_sem); |
4ffef5fe DN |
5251 | |
5252 | precharge = mc.precharge; | |
5253 | mc.precharge = 0; | |
5254 | ||
5255 | return precharge; | |
5256 | } | |
5257 | ||
4ffef5fe DN |
5258 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
5259 | { | |
dfe076b0 DN |
5260 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
5261 | ||
5262 | VM_BUG_ON(mc.moving_task); | |
5263 | mc.moving_task = current; | |
5264 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
5265 | } |
5266 | ||
dfe076b0 DN |
5267 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
5268 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 5269 | { |
2bd9bb20 KH |
5270 | struct mem_cgroup *from = mc.from; |
5271 | struct mem_cgroup *to = mc.to; | |
5272 | ||
4ffef5fe | 5273 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d DN |
5274 | if (mc.precharge) { |
5275 | __mem_cgroup_cancel_charge(mc.to, mc.precharge); | |
5276 | mc.precharge = 0; | |
5277 | } | |
5278 | /* | |
5279 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
5280 | * we must uncharge here. | |
5281 | */ | |
5282 | if (mc.moved_charge) { | |
5283 | __mem_cgroup_cancel_charge(mc.from, mc.moved_charge); | |
5284 | mc.moved_charge = 0; | |
4ffef5fe | 5285 | } |
483c30b5 DN |
5286 | /* we must fixup refcnts and charges */ |
5287 | if (mc.moved_swap) { | |
483c30b5 DN |
5288 | /* uncharge swap account from the old cgroup */ |
5289 | if (!mem_cgroup_is_root(mc.from)) | |
5290 | res_counter_uncharge(&mc.from->memsw, | |
5291 | PAGE_SIZE * mc.moved_swap); | |
5292 | __mem_cgroup_put(mc.from, mc.moved_swap); | |
5293 | ||
5294 | if (!mem_cgroup_is_root(mc.to)) { | |
5295 | /* | |
5296 | * we charged both to->res and to->memsw, so we should | |
5297 | * uncharge to->res. | |
5298 | */ | |
5299 | res_counter_uncharge(&mc.to->res, | |
5300 | PAGE_SIZE * mc.moved_swap); | |
483c30b5 DN |
5301 | } |
5302 | /* we've already done mem_cgroup_get(mc.to) */ | |
483c30b5 DN |
5303 | mc.moved_swap = 0; |
5304 | } | |
dfe076b0 DN |
5305 | memcg_oom_recover(from); |
5306 | memcg_oom_recover(to); | |
5307 | wake_up_all(&mc.waitq); | |
5308 | } | |
5309 | ||
5310 | static void mem_cgroup_clear_mc(void) | |
5311 | { | |
5312 | struct mem_cgroup *from = mc.from; | |
5313 | ||
5314 | /* | |
5315 | * we must clear moving_task before waking up waiters at the end of | |
5316 | * task migration. | |
5317 | */ | |
5318 | mc.moving_task = NULL; | |
5319 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 5320 | spin_lock(&mc.lock); |
4ffef5fe DN |
5321 | mc.from = NULL; |
5322 | mc.to = NULL; | |
2bd9bb20 | 5323 | spin_unlock(&mc.lock); |
32047e2a | 5324 | mem_cgroup_end_move(from); |
4ffef5fe DN |
5325 | } |
5326 | ||
7dc74be0 DN |
5327 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, |
5328 | struct cgroup *cgroup, | |
f780bdb7 | 5329 | struct task_struct *p) |
7dc74be0 DN |
5330 | { |
5331 | int ret = 0; | |
5332 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgroup); | |
5333 | ||
5334 | if (mem->move_charge_at_immigrate) { | |
5335 | struct mm_struct *mm; | |
5336 | struct mem_cgroup *from = mem_cgroup_from_task(p); | |
5337 | ||
5338 | VM_BUG_ON(from == mem); | |
5339 | ||
5340 | mm = get_task_mm(p); | |
5341 | if (!mm) | |
5342 | return 0; | |
7dc74be0 | 5343 | /* We move charges only when we move a owner of the mm */ |
4ffef5fe DN |
5344 | if (mm->owner == p) { |
5345 | VM_BUG_ON(mc.from); | |
5346 | VM_BUG_ON(mc.to); | |
5347 | VM_BUG_ON(mc.precharge); | |
854ffa8d | 5348 | VM_BUG_ON(mc.moved_charge); |
483c30b5 | 5349 | VM_BUG_ON(mc.moved_swap); |
32047e2a | 5350 | mem_cgroup_start_move(from); |
2bd9bb20 | 5351 | spin_lock(&mc.lock); |
4ffef5fe DN |
5352 | mc.from = from; |
5353 | mc.to = mem; | |
2bd9bb20 | 5354 | spin_unlock(&mc.lock); |
dfe076b0 | 5355 | /* We set mc.moving_task later */ |
4ffef5fe DN |
5356 | |
5357 | ret = mem_cgroup_precharge_mc(mm); | |
5358 | if (ret) | |
5359 | mem_cgroup_clear_mc(); | |
dfe076b0 DN |
5360 | } |
5361 | mmput(mm); | |
7dc74be0 DN |
5362 | } |
5363 | return ret; | |
5364 | } | |
5365 | ||
5366 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, | |
5367 | struct cgroup *cgroup, | |
f780bdb7 | 5368 | struct task_struct *p) |
7dc74be0 | 5369 | { |
4ffef5fe | 5370 | mem_cgroup_clear_mc(); |
7dc74be0 DN |
5371 | } |
5372 | ||
4ffef5fe DN |
5373 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
5374 | unsigned long addr, unsigned long end, | |
5375 | struct mm_walk *walk) | |
7dc74be0 | 5376 | { |
4ffef5fe DN |
5377 | int ret = 0; |
5378 | struct vm_area_struct *vma = walk->private; | |
5379 | pte_t *pte; | |
5380 | spinlock_t *ptl; | |
5381 | ||
03319327 | 5382 | split_huge_page_pmd(walk->mm, pmd); |
4ffef5fe DN |
5383 | retry: |
5384 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
5385 | for (; addr != end; addr += PAGE_SIZE) { | |
5386 | pte_t ptent = *(pte++); | |
5387 | union mc_target target; | |
5388 | int type; | |
5389 | struct page *page; | |
5390 | struct page_cgroup *pc; | |
02491447 | 5391 | swp_entry_t ent; |
4ffef5fe DN |
5392 | |
5393 | if (!mc.precharge) | |
5394 | break; | |
5395 | ||
5396 | type = is_target_pte_for_mc(vma, addr, ptent, &target); | |
5397 | switch (type) { | |
5398 | case MC_TARGET_PAGE: | |
5399 | page = target.page; | |
5400 | if (isolate_lru_page(page)) | |
5401 | goto put; | |
5402 | pc = lookup_page_cgroup(page); | |
7ec99d62 JW |
5403 | if (!mem_cgroup_move_account(page, 1, pc, |
5404 | mc.from, mc.to, false)) { | |
4ffef5fe | 5405 | mc.precharge--; |
854ffa8d DN |
5406 | /* we uncharge from mc.from later. */ |
5407 | mc.moved_charge++; | |
4ffef5fe DN |
5408 | } |
5409 | putback_lru_page(page); | |
5410 | put: /* is_target_pte_for_mc() gets the page */ | |
5411 | put_page(page); | |
5412 | break; | |
02491447 DN |
5413 | case MC_TARGET_SWAP: |
5414 | ent = target.ent; | |
483c30b5 DN |
5415 | if (!mem_cgroup_move_swap_account(ent, |
5416 | mc.from, mc.to, false)) { | |
02491447 | 5417 | mc.precharge--; |
483c30b5 DN |
5418 | /* we fixup refcnts and charges later. */ |
5419 | mc.moved_swap++; | |
5420 | } | |
02491447 | 5421 | break; |
4ffef5fe DN |
5422 | default: |
5423 | break; | |
5424 | } | |
5425 | } | |
5426 | pte_unmap_unlock(pte - 1, ptl); | |
5427 | cond_resched(); | |
5428 | ||
5429 | if (addr != end) { | |
5430 | /* | |
5431 | * We have consumed all precharges we got in can_attach(). | |
5432 | * We try charge one by one, but don't do any additional | |
5433 | * charges to mc.to if we have failed in charge once in attach() | |
5434 | * phase. | |
5435 | */ | |
854ffa8d | 5436 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
5437 | if (!ret) |
5438 | goto retry; | |
5439 | } | |
5440 | ||
5441 | return ret; | |
5442 | } | |
5443 | ||
5444 | static void mem_cgroup_move_charge(struct mm_struct *mm) | |
5445 | { | |
5446 | struct vm_area_struct *vma; | |
5447 | ||
5448 | lru_add_drain_all(); | |
dfe076b0 DN |
5449 | retry: |
5450 | if (unlikely(!down_read_trylock(&mm->mmap_sem))) { | |
5451 | /* | |
5452 | * Someone who are holding the mmap_sem might be waiting in | |
5453 | * waitq. So we cancel all extra charges, wake up all waiters, | |
5454 | * and retry. Because we cancel precharges, we might not be able | |
5455 | * to move enough charges, but moving charge is a best-effort | |
5456 | * feature anyway, so it wouldn't be a big problem. | |
5457 | */ | |
5458 | __mem_cgroup_clear_mc(); | |
5459 | cond_resched(); | |
5460 | goto retry; | |
5461 | } | |
4ffef5fe DN |
5462 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5463 | int ret; | |
5464 | struct mm_walk mem_cgroup_move_charge_walk = { | |
5465 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
5466 | .mm = mm, | |
5467 | .private = vma, | |
5468 | }; | |
5469 | if (is_vm_hugetlb_page(vma)) | |
5470 | continue; | |
4ffef5fe DN |
5471 | ret = walk_page_range(vma->vm_start, vma->vm_end, |
5472 | &mem_cgroup_move_charge_walk); | |
5473 | if (ret) | |
5474 | /* | |
5475 | * means we have consumed all precharges and failed in | |
5476 | * doing additional charge. Just abandon here. | |
5477 | */ | |
5478 | break; | |
5479 | } | |
dfe076b0 | 5480 | up_read(&mm->mmap_sem); |
7dc74be0 DN |
5481 | } |
5482 | ||
67e465a7 BS |
5483 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, |
5484 | struct cgroup *cont, | |
5485 | struct cgroup *old_cont, | |
f780bdb7 | 5486 | struct task_struct *p) |
67e465a7 | 5487 | { |
a433658c | 5488 | struct mm_struct *mm = get_task_mm(p); |
dfe076b0 | 5489 | |
dfe076b0 | 5490 | if (mm) { |
a433658c KM |
5491 | if (mc.to) |
5492 | mem_cgroup_move_charge(mm); | |
5493 | put_swap_token(mm); | |
dfe076b0 DN |
5494 | mmput(mm); |
5495 | } | |
a433658c KM |
5496 | if (mc.to) |
5497 | mem_cgroup_clear_mc(); | |
67e465a7 | 5498 | } |
5cfb80a7 DN |
5499 | #else /* !CONFIG_MMU */ |
5500 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, | |
5501 | struct cgroup *cgroup, | |
f780bdb7 | 5502 | struct task_struct *p) |
5cfb80a7 DN |
5503 | { |
5504 | return 0; | |
5505 | } | |
5506 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, | |
5507 | struct cgroup *cgroup, | |
f780bdb7 | 5508 | struct task_struct *p) |
5cfb80a7 DN |
5509 | { |
5510 | } | |
5511 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, | |
5512 | struct cgroup *cont, | |
5513 | struct cgroup *old_cont, | |
f780bdb7 | 5514 | struct task_struct *p) |
5cfb80a7 DN |
5515 | { |
5516 | } | |
5517 | #endif | |
67e465a7 | 5518 | |
8cdea7c0 BS |
5519 | struct cgroup_subsys mem_cgroup_subsys = { |
5520 | .name = "memory", | |
5521 | .subsys_id = mem_cgroup_subsys_id, | |
5522 | .create = mem_cgroup_create, | |
df878fb0 | 5523 | .pre_destroy = mem_cgroup_pre_destroy, |
8cdea7c0 BS |
5524 | .destroy = mem_cgroup_destroy, |
5525 | .populate = mem_cgroup_populate, | |
7dc74be0 DN |
5526 | .can_attach = mem_cgroup_can_attach, |
5527 | .cancel_attach = mem_cgroup_cancel_attach, | |
67e465a7 | 5528 | .attach = mem_cgroup_move_task, |
6d12e2d8 | 5529 | .early_init = 0, |
04046e1a | 5530 | .use_id = 1, |
8cdea7c0 | 5531 | }; |
c077719b KH |
5532 | |
5533 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
a42c390c MH |
5534 | static int __init enable_swap_account(char *s) |
5535 | { | |
5536 | /* consider enabled if no parameter or 1 is given */ | |
a2c8990a | 5537 | if (!strcmp(s, "1")) |
a42c390c | 5538 | really_do_swap_account = 1; |
a2c8990a | 5539 | else if (!strcmp(s, "0")) |
a42c390c MH |
5540 | really_do_swap_account = 0; |
5541 | return 1; | |
5542 | } | |
a2c8990a | 5543 | __setup("swapaccount=", enable_swap_account); |
c077719b | 5544 | |
c077719b | 5545 | #endif |