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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; | |
867578cb | 249 | atomic_t oom_lock; |
8c7c6e34 | 250 | atomic_t refcnt; |
14797e23 | 251 | |
a7885eb8 | 252 | unsigned int swappiness; |
3c11ecf4 KH |
253 | /* OOM-Killer disable */ |
254 | int oom_kill_disable; | |
a7885eb8 | 255 | |
22a668d7 KH |
256 | /* set when res.limit == memsw.limit */ |
257 | bool memsw_is_minimum; | |
258 | ||
2e72b634 KS |
259 | /* protect arrays of thresholds */ |
260 | struct mutex thresholds_lock; | |
261 | ||
262 | /* thresholds for memory usage. RCU-protected */ | |
2c488db2 | 263 | struct mem_cgroup_thresholds thresholds; |
907860ed | 264 | |
2e72b634 | 265 | /* thresholds for mem+swap usage. RCU-protected */ |
2c488db2 | 266 | struct mem_cgroup_thresholds memsw_thresholds; |
907860ed | 267 | |
9490ff27 KH |
268 | /* For oom notifier event fd */ |
269 | struct list_head oom_notify; | |
270 | ||
7dc74be0 DN |
271 | /* |
272 | * Should we move charges of a task when a task is moved into this | |
273 | * mem_cgroup ? And what type of charges should we move ? | |
274 | */ | |
275 | unsigned long move_charge_at_immigrate; | |
d52aa412 | 276 | /* |
c62b1a3b | 277 | * percpu counter. |
d52aa412 | 278 | */ |
c62b1a3b | 279 | struct mem_cgroup_stat_cpu *stat; |
711d3d2c KH |
280 | /* |
281 | * used when a cpu is offlined or other synchronizations | |
282 | * See mem_cgroup_read_stat(). | |
283 | */ | |
284 | struct mem_cgroup_stat_cpu nocpu_base; | |
285 | spinlock_t pcp_counter_lock; | |
8cdea7c0 BS |
286 | }; |
287 | ||
7dc74be0 DN |
288 | /* Stuffs for move charges at task migration. */ |
289 | /* | |
290 | * Types of charges to be moved. "move_charge_at_immitgrate" is treated as a | |
291 | * left-shifted bitmap of these types. | |
292 | */ | |
293 | enum move_type { | |
4ffef5fe | 294 | MOVE_CHARGE_TYPE_ANON, /* private anonymous page and swap of it */ |
87946a72 | 295 | MOVE_CHARGE_TYPE_FILE, /* file page(including tmpfs) and swap of it */ |
7dc74be0 DN |
296 | NR_MOVE_TYPE, |
297 | }; | |
298 | ||
4ffef5fe DN |
299 | /* "mc" and its members are protected by cgroup_mutex */ |
300 | static struct move_charge_struct { | |
b1dd693e | 301 | spinlock_t lock; /* for from, to */ |
4ffef5fe DN |
302 | struct mem_cgroup *from; |
303 | struct mem_cgroup *to; | |
304 | unsigned long precharge; | |
854ffa8d | 305 | unsigned long moved_charge; |
483c30b5 | 306 | unsigned long moved_swap; |
8033b97c DN |
307 | struct task_struct *moving_task; /* a task moving charges */ |
308 | wait_queue_head_t waitq; /* a waitq for other context */ | |
309 | } mc = { | |
2bd9bb20 | 310 | .lock = __SPIN_LOCK_UNLOCKED(mc.lock), |
8033b97c DN |
311 | .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), |
312 | }; | |
4ffef5fe | 313 | |
90254a65 DN |
314 | static bool move_anon(void) |
315 | { | |
316 | return test_bit(MOVE_CHARGE_TYPE_ANON, | |
317 | &mc.to->move_charge_at_immigrate); | |
318 | } | |
319 | ||
87946a72 DN |
320 | static bool move_file(void) |
321 | { | |
322 | return test_bit(MOVE_CHARGE_TYPE_FILE, | |
323 | &mc.to->move_charge_at_immigrate); | |
324 | } | |
325 | ||
4e416953 BS |
326 | /* |
327 | * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft | |
328 | * limit reclaim to prevent infinite loops, if they ever occur. | |
329 | */ | |
330 | #define MEM_CGROUP_MAX_RECLAIM_LOOPS (100) | |
331 | #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS (2) | |
332 | ||
217bc319 KH |
333 | enum charge_type { |
334 | MEM_CGROUP_CHARGE_TYPE_CACHE = 0, | |
335 | MEM_CGROUP_CHARGE_TYPE_MAPPED, | |
4f98a2fe | 336 | MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ |
c05555b5 | 337 | MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ |
d13d1443 | 338 | MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ |
8a9478ca | 339 | MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ |
c05555b5 KH |
340 | NR_CHARGE_TYPE, |
341 | }; | |
342 | ||
8c7c6e34 KH |
343 | /* for encoding cft->private value on file */ |
344 | #define _MEM (0) | |
345 | #define _MEMSWAP (1) | |
9490ff27 | 346 | #define _OOM_TYPE (2) |
8c7c6e34 KH |
347 | #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val)) |
348 | #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff) | |
349 | #define MEMFILE_ATTR(val) ((val) & 0xffff) | |
9490ff27 KH |
350 | /* Used for OOM nofiier */ |
351 | #define OOM_CONTROL (0) | |
8c7c6e34 | 352 | |
75822b44 BS |
353 | /* |
354 | * Reclaim flags for mem_cgroup_hierarchical_reclaim | |
355 | */ | |
356 | #define MEM_CGROUP_RECLAIM_NOSWAP_BIT 0x0 | |
357 | #define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT) | |
358 | #define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1 | |
359 | #define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT) | |
4e416953 BS |
360 | #define MEM_CGROUP_RECLAIM_SOFT_BIT 0x2 |
361 | #define MEM_CGROUP_RECLAIM_SOFT (1 << MEM_CGROUP_RECLAIM_SOFT_BIT) | |
75822b44 | 362 | |
8c7c6e34 KH |
363 | static void mem_cgroup_get(struct mem_cgroup *mem); |
364 | static void mem_cgroup_put(struct mem_cgroup *mem); | |
7bcc1bb1 | 365 | static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem); |
26fe6168 | 366 | static void drain_all_stock_async(struct mem_cgroup *mem); |
8c7c6e34 | 367 | |
f64c3f54 BS |
368 | static struct mem_cgroup_per_zone * |
369 | mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid) | |
370 | { | |
371 | return &mem->info.nodeinfo[nid]->zoneinfo[zid]; | |
372 | } | |
373 | ||
d324236b WF |
374 | struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *mem) |
375 | { | |
376 | return &mem->css; | |
377 | } | |
378 | ||
f64c3f54 | 379 | static struct mem_cgroup_per_zone * |
97a6c37b | 380 | page_cgroup_zoneinfo(struct mem_cgroup *mem, struct page *page) |
f64c3f54 | 381 | { |
97a6c37b JW |
382 | int nid = page_to_nid(page); |
383 | int zid = page_zonenum(page); | |
f64c3f54 | 384 | |
f64c3f54 BS |
385 | return mem_cgroup_zoneinfo(mem, nid, zid); |
386 | } | |
387 | ||
388 | static struct mem_cgroup_tree_per_zone * | |
389 | soft_limit_tree_node_zone(int nid, int zid) | |
390 | { | |
391 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
392 | } | |
393 | ||
394 | static struct mem_cgroup_tree_per_zone * | |
395 | soft_limit_tree_from_page(struct page *page) | |
396 | { | |
397 | int nid = page_to_nid(page); | |
398 | int zid = page_zonenum(page); | |
399 | ||
400 | return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; | |
401 | } | |
402 | ||
403 | static void | |
4e416953 | 404 | __mem_cgroup_insert_exceeded(struct mem_cgroup *mem, |
f64c3f54 | 405 | struct mem_cgroup_per_zone *mz, |
ef8745c1 KH |
406 | struct mem_cgroup_tree_per_zone *mctz, |
407 | unsigned long long new_usage_in_excess) | |
f64c3f54 BS |
408 | { |
409 | struct rb_node **p = &mctz->rb_root.rb_node; | |
410 | struct rb_node *parent = NULL; | |
411 | struct mem_cgroup_per_zone *mz_node; | |
412 | ||
413 | if (mz->on_tree) | |
414 | return; | |
415 | ||
ef8745c1 KH |
416 | mz->usage_in_excess = new_usage_in_excess; |
417 | if (!mz->usage_in_excess) | |
418 | return; | |
f64c3f54 BS |
419 | while (*p) { |
420 | parent = *p; | |
421 | mz_node = rb_entry(parent, struct mem_cgroup_per_zone, | |
422 | tree_node); | |
423 | if (mz->usage_in_excess < mz_node->usage_in_excess) | |
424 | p = &(*p)->rb_left; | |
425 | /* | |
426 | * We can't avoid mem cgroups that are over their soft | |
427 | * limit by the same amount | |
428 | */ | |
429 | else if (mz->usage_in_excess >= mz_node->usage_in_excess) | |
430 | p = &(*p)->rb_right; | |
431 | } | |
432 | rb_link_node(&mz->tree_node, parent, p); | |
433 | rb_insert_color(&mz->tree_node, &mctz->rb_root); | |
434 | mz->on_tree = true; | |
4e416953 BS |
435 | } |
436 | ||
437 | static void | |
438 | __mem_cgroup_remove_exceeded(struct mem_cgroup *mem, | |
439 | struct mem_cgroup_per_zone *mz, | |
440 | struct mem_cgroup_tree_per_zone *mctz) | |
441 | { | |
442 | if (!mz->on_tree) | |
443 | return; | |
444 | rb_erase(&mz->tree_node, &mctz->rb_root); | |
445 | mz->on_tree = false; | |
446 | } | |
447 | ||
f64c3f54 BS |
448 | static void |
449 | mem_cgroup_remove_exceeded(struct mem_cgroup *mem, | |
450 | struct mem_cgroup_per_zone *mz, | |
451 | struct mem_cgroup_tree_per_zone *mctz) | |
452 | { | |
453 | spin_lock(&mctz->lock); | |
4e416953 | 454 | __mem_cgroup_remove_exceeded(mem, mz, mctz); |
f64c3f54 BS |
455 | spin_unlock(&mctz->lock); |
456 | } | |
457 | ||
f64c3f54 BS |
458 | |
459 | static void mem_cgroup_update_tree(struct mem_cgroup *mem, struct page *page) | |
460 | { | |
ef8745c1 | 461 | unsigned long long excess; |
f64c3f54 BS |
462 | struct mem_cgroup_per_zone *mz; |
463 | struct mem_cgroup_tree_per_zone *mctz; | |
4e649152 KH |
464 | int nid = page_to_nid(page); |
465 | int zid = page_zonenum(page); | |
f64c3f54 BS |
466 | mctz = soft_limit_tree_from_page(page); |
467 | ||
468 | /* | |
4e649152 KH |
469 | * Necessary to update all ancestors when hierarchy is used. |
470 | * because their event counter is not touched. | |
f64c3f54 | 471 | */ |
4e649152 KH |
472 | for (; mem; mem = parent_mem_cgroup(mem)) { |
473 | mz = mem_cgroup_zoneinfo(mem, nid, zid); | |
ef8745c1 | 474 | excess = res_counter_soft_limit_excess(&mem->res); |
4e649152 KH |
475 | /* |
476 | * We have to update the tree if mz is on RB-tree or | |
477 | * mem is over its softlimit. | |
478 | */ | |
ef8745c1 | 479 | if (excess || mz->on_tree) { |
4e649152 KH |
480 | spin_lock(&mctz->lock); |
481 | /* if on-tree, remove it */ | |
482 | if (mz->on_tree) | |
483 | __mem_cgroup_remove_exceeded(mem, mz, mctz); | |
484 | /* | |
ef8745c1 KH |
485 | * Insert again. mz->usage_in_excess will be updated. |
486 | * If excess is 0, no tree ops. | |
4e649152 | 487 | */ |
ef8745c1 | 488 | __mem_cgroup_insert_exceeded(mem, mz, mctz, excess); |
4e649152 KH |
489 | spin_unlock(&mctz->lock); |
490 | } | |
f64c3f54 BS |
491 | } |
492 | } | |
493 | ||
494 | static void mem_cgroup_remove_from_trees(struct mem_cgroup *mem) | |
495 | { | |
496 | int node, zone; | |
497 | struct mem_cgroup_per_zone *mz; | |
498 | struct mem_cgroup_tree_per_zone *mctz; | |
499 | ||
500 | for_each_node_state(node, N_POSSIBLE) { | |
501 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
502 | mz = mem_cgroup_zoneinfo(mem, node, zone); | |
503 | mctz = soft_limit_tree_node_zone(node, zone); | |
504 | mem_cgroup_remove_exceeded(mem, mz, mctz); | |
505 | } | |
506 | } | |
507 | } | |
508 | ||
4e416953 BS |
509 | static struct mem_cgroup_per_zone * |
510 | __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
511 | { | |
512 | struct rb_node *rightmost = NULL; | |
26251eaf | 513 | struct mem_cgroup_per_zone *mz; |
4e416953 BS |
514 | |
515 | retry: | |
26251eaf | 516 | mz = NULL; |
4e416953 BS |
517 | rightmost = rb_last(&mctz->rb_root); |
518 | if (!rightmost) | |
519 | goto done; /* Nothing to reclaim from */ | |
520 | ||
521 | mz = rb_entry(rightmost, struct mem_cgroup_per_zone, tree_node); | |
522 | /* | |
523 | * Remove the node now but someone else can add it back, | |
524 | * we will to add it back at the end of reclaim to its correct | |
525 | * position in the tree. | |
526 | */ | |
527 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); | |
528 | if (!res_counter_soft_limit_excess(&mz->mem->res) || | |
529 | !css_tryget(&mz->mem->css)) | |
530 | goto retry; | |
531 | done: | |
532 | return mz; | |
533 | } | |
534 | ||
535 | static struct mem_cgroup_per_zone * | |
536 | mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) | |
537 | { | |
538 | struct mem_cgroup_per_zone *mz; | |
539 | ||
540 | spin_lock(&mctz->lock); | |
541 | mz = __mem_cgroup_largest_soft_limit_node(mctz); | |
542 | spin_unlock(&mctz->lock); | |
543 | return mz; | |
544 | } | |
545 | ||
711d3d2c KH |
546 | /* |
547 | * Implementation Note: reading percpu statistics for memcg. | |
548 | * | |
549 | * Both of vmstat[] and percpu_counter has threshold and do periodic | |
550 | * synchronization to implement "quick" read. There are trade-off between | |
551 | * reading cost and precision of value. Then, we may have a chance to implement | |
552 | * a periodic synchronizion of counter in memcg's counter. | |
553 | * | |
554 | * But this _read() function is used for user interface now. The user accounts | |
555 | * memory usage by memory cgroup and he _always_ requires exact value because | |
556 | * he accounts memory. Even if we provide quick-and-fuzzy read, we always | |
557 | * have to visit all online cpus and make sum. So, for now, unnecessary | |
558 | * synchronization is not implemented. (just implemented for cpu hotplug) | |
559 | * | |
560 | * If there are kernel internal actions which can make use of some not-exact | |
561 | * value, and reading all cpu value can be performance bottleneck in some | |
562 | * common workload, threashold and synchonization as vmstat[] should be | |
563 | * implemented. | |
564 | */ | |
7a159cc9 JW |
565 | static long mem_cgroup_read_stat(struct mem_cgroup *mem, |
566 | enum mem_cgroup_stat_index idx) | |
c62b1a3b | 567 | { |
7a159cc9 | 568 | long val = 0; |
c62b1a3b | 569 | int cpu; |
c62b1a3b | 570 | |
711d3d2c KH |
571 | get_online_cpus(); |
572 | for_each_online_cpu(cpu) | |
c62b1a3b | 573 | val += per_cpu(mem->stat->count[idx], cpu); |
711d3d2c KH |
574 | #ifdef CONFIG_HOTPLUG_CPU |
575 | spin_lock(&mem->pcp_counter_lock); | |
576 | val += mem->nocpu_base.count[idx]; | |
577 | spin_unlock(&mem->pcp_counter_lock); | |
578 | #endif | |
579 | put_online_cpus(); | |
c62b1a3b KH |
580 | return val; |
581 | } | |
582 | ||
0c3e73e8 BS |
583 | static void mem_cgroup_swap_statistics(struct mem_cgroup *mem, |
584 | bool charge) | |
585 | { | |
586 | int val = (charge) ? 1 : -1; | |
c62b1a3b | 587 | this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_SWAPOUT], val); |
0c3e73e8 BS |
588 | } |
589 | ||
456f998e YH |
590 | void mem_cgroup_pgfault(struct mem_cgroup *mem, int val) |
591 | { | |
592 | this_cpu_add(mem->stat->events[MEM_CGROUP_EVENTS_PGFAULT], val); | |
593 | } | |
594 | ||
595 | void mem_cgroup_pgmajfault(struct mem_cgroup *mem, int val) | |
596 | { | |
597 | this_cpu_add(mem->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT], val); | |
598 | } | |
599 | ||
e9f8974f JW |
600 | static unsigned long mem_cgroup_read_events(struct mem_cgroup *mem, |
601 | enum mem_cgroup_events_index idx) | |
602 | { | |
603 | unsigned long val = 0; | |
604 | int cpu; | |
605 | ||
606 | for_each_online_cpu(cpu) | |
607 | val += per_cpu(mem->stat->events[idx], cpu); | |
608 | #ifdef CONFIG_HOTPLUG_CPU | |
609 | spin_lock(&mem->pcp_counter_lock); | |
610 | val += mem->nocpu_base.events[idx]; | |
611 | spin_unlock(&mem->pcp_counter_lock); | |
612 | #endif | |
613 | return val; | |
614 | } | |
615 | ||
c05555b5 | 616 | static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, |
e401f176 | 617 | bool file, int nr_pages) |
d52aa412 | 618 | { |
c62b1a3b KH |
619 | preempt_disable(); |
620 | ||
e401f176 KH |
621 | if (file) |
622 | __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_CACHE], nr_pages); | |
d52aa412 | 623 | else |
e401f176 | 624 | __this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_RSS], nr_pages); |
55e462b0 | 625 | |
e401f176 KH |
626 | /* pagein of a big page is an event. So, ignore page size */ |
627 | if (nr_pages > 0) | |
e9f8974f | 628 | __this_cpu_inc(mem->stat->events[MEM_CGROUP_EVENTS_PGPGIN]); |
3751d604 | 629 | else { |
e9f8974f | 630 | __this_cpu_inc(mem->stat->events[MEM_CGROUP_EVENTS_PGPGOUT]); |
3751d604 KH |
631 | nr_pages = -nr_pages; /* for event */ |
632 | } | |
e401f176 | 633 | |
e9f8974f | 634 | __this_cpu_add(mem->stat->events[MEM_CGROUP_EVENTS_COUNT], nr_pages); |
2e72b634 | 635 | |
c62b1a3b | 636 | preempt_enable(); |
6d12e2d8 KH |
637 | } |
638 | ||
889976db YH |
639 | static unsigned long |
640 | mem_cgroup_get_zonestat_node(struct mem_cgroup *mem, int nid, enum lru_list idx) | |
641 | { | |
642 | struct mem_cgroup_per_zone *mz; | |
643 | u64 total = 0; | |
644 | int zid; | |
645 | ||
646 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
647 | mz = mem_cgroup_zoneinfo(mem, nid, zid); | |
648 | total += MEM_CGROUP_ZSTAT(mz, idx); | |
649 | } | |
650 | return total; | |
651 | } | |
14067bb3 | 652 | static unsigned long mem_cgroup_get_local_zonestat(struct mem_cgroup *mem, |
b69408e8 | 653 | enum lru_list idx) |
6d12e2d8 | 654 | { |
889976db | 655 | int nid; |
6d12e2d8 KH |
656 | u64 total = 0; |
657 | ||
658 | for_each_online_node(nid) | |
889976db | 659 | total += mem_cgroup_get_zonestat_node(mem, nid, idx); |
6d12e2d8 | 660 | return total; |
d52aa412 KH |
661 | } |
662 | ||
7a159cc9 JW |
663 | static bool __memcg_event_check(struct mem_cgroup *mem, int target) |
664 | { | |
665 | unsigned long val, next; | |
666 | ||
667 | val = this_cpu_read(mem->stat->events[MEM_CGROUP_EVENTS_COUNT]); | |
668 | next = this_cpu_read(mem->stat->targets[target]); | |
669 | /* from time_after() in jiffies.h */ | |
670 | return ((long)next - (long)val < 0); | |
671 | } | |
672 | ||
673 | static void __mem_cgroup_target_update(struct mem_cgroup *mem, int target) | |
d2265e6f | 674 | { |
7a159cc9 | 675 | unsigned long val, next; |
d2265e6f | 676 | |
e9f8974f | 677 | val = this_cpu_read(mem->stat->events[MEM_CGROUP_EVENTS_COUNT]); |
d2265e6f | 678 | |
7a159cc9 JW |
679 | switch (target) { |
680 | case MEM_CGROUP_TARGET_THRESH: | |
681 | next = val + THRESHOLDS_EVENTS_TARGET; | |
682 | break; | |
683 | case MEM_CGROUP_TARGET_SOFTLIMIT: | |
684 | next = val + SOFTLIMIT_EVENTS_TARGET; | |
685 | break; | |
453a9bf3 KH |
686 | case MEM_CGROUP_TARGET_NUMAINFO: |
687 | next = val + NUMAINFO_EVENTS_TARGET; | |
688 | break; | |
7a159cc9 JW |
689 | default: |
690 | return; | |
691 | } | |
692 | ||
693 | this_cpu_write(mem->stat->targets[target], next); | |
d2265e6f KH |
694 | } |
695 | ||
696 | /* | |
697 | * Check events in order. | |
698 | * | |
699 | */ | |
700 | static void memcg_check_events(struct mem_cgroup *mem, struct page *page) | |
701 | { | |
702 | /* threshold event is triggered in finer grain than soft limit */ | |
7a159cc9 | 703 | if (unlikely(__memcg_event_check(mem, MEM_CGROUP_TARGET_THRESH))) { |
d2265e6f | 704 | mem_cgroup_threshold(mem); |
7a159cc9 JW |
705 | __mem_cgroup_target_update(mem, MEM_CGROUP_TARGET_THRESH); |
706 | if (unlikely(__memcg_event_check(mem, | |
453a9bf3 | 707 | MEM_CGROUP_TARGET_SOFTLIMIT))) { |
d2265e6f | 708 | mem_cgroup_update_tree(mem, page); |
7a159cc9 | 709 | __mem_cgroup_target_update(mem, |
453a9bf3 KH |
710 | MEM_CGROUP_TARGET_SOFTLIMIT); |
711 | } | |
712 | #if MAX_NUMNODES > 1 | |
713 | if (unlikely(__memcg_event_check(mem, | |
714 | MEM_CGROUP_TARGET_NUMAINFO))) { | |
715 | atomic_inc(&mem->numainfo_events); | |
716 | __mem_cgroup_target_update(mem, | |
717 | MEM_CGROUP_TARGET_NUMAINFO); | |
7a159cc9 | 718 | } |
453a9bf3 | 719 | #endif |
d2265e6f KH |
720 | } |
721 | } | |
722 | ||
d5b69e38 | 723 | static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) |
8cdea7c0 BS |
724 | { |
725 | return container_of(cgroup_subsys_state(cont, | |
726 | mem_cgroup_subsys_id), struct mem_cgroup, | |
727 | css); | |
728 | } | |
729 | ||
cf475ad2 | 730 | struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) |
78fb7466 | 731 | { |
31a78f23 BS |
732 | /* |
733 | * mm_update_next_owner() may clear mm->owner to NULL | |
734 | * if it races with swapoff, page migration, etc. | |
735 | * So this can be called with p == NULL. | |
736 | */ | |
737 | if (unlikely(!p)) | |
738 | return NULL; | |
739 | ||
78fb7466 PE |
740 | return container_of(task_subsys_state(p, mem_cgroup_subsys_id), |
741 | struct mem_cgroup, css); | |
742 | } | |
743 | ||
a433658c | 744 | struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) |
54595fe2 KH |
745 | { |
746 | struct mem_cgroup *mem = NULL; | |
0b7f569e KH |
747 | |
748 | if (!mm) | |
749 | return NULL; | |
54595fe2 KH |
750 | /* |
751 | * Because we have no locks, mm->owner's may be being moved to other | |
752 | * cgroup. We use css_tryget() here even if this looks | |
753 | * pessimistic (rather than adding locks here). | |
754 | */ | |
755 | rcu_read_lock(); | |
756 | do { | |
757 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
758 | if (unlikely(!mem)) | |
759 | break; | |
760 | } while (!css_tryget(&mem->css)); | |
761 | rcu_read_unlock(); | |
762 | return mem; | |
763 | } | |
764 | ||
7d74b06f KH |
765 | /* The caller has to guarantee "mem" exists before calling this */ |
766 | static struct mem_cgroup *mem_cgroup_start_loop(struct mem_cgroup *mem) | |
14067bb3 | 767 | { |
711d3d2c KH |
768 | struct cgroup_subsys_state *css; |
769 | int found; | |
770 | ||
771 | if (!mem) /* ROOT cgroup has the smallest ID */ | |
772 | return root_mem_cgroup; /*css_put/get against root is ignored*/ | |
773 | if (!mem->use_hierarchy) { | |
774 | if (css_tryget(&mem->css)) | |
775 | return mem; | |
776 | return NULL; | |
777 | } | |
778 | rcu_read_lock(); | |
779 | /* | |
780 | * searching a memory cgroup which has the smallest ID under given | |
781 | * ROOT cgroup. (ID >= 1) | |
782 | */ | |
783 | css = css_get_next(&mem_cgroup_subsys, 1, &mem->css, &found); | |
784 | if (css && css_tryget(css)) | |
785 | mem = container_of(css, struct mem_cgroup, css); | |
786 | else | |
787 | mem = NULL; | |
788 | rcu_read_unlock(); | |
789 | return mem; | |
7d74b06f KH |
790 | } |
791 | ||
792 | static struct mem_cgroup *mem_cgroup_get_next(struct mem_cgroup *iter, | |
793 | struct mem_cgroup *root, | |
794 | bool cond) | |
795 | { | |
796 | int nextid = css_id(&iter->css) + 1; | |
797 | int found; | |
798 | int hierarchy_used; | |
14067bb3 | 799 | struct cgroup_subsys_state *css; |
14067bb3 | 800 | |
7d74b06f | 801 | hierarchy_used = iter->use_hierarchy; |
14067bb3 | 802 | |
7d74b06f | 803 | css_put(&iter->css); |
711d3d2c KH |
804 | /* If no ROOT, walk all, ignore hierarchy */ |
805 | if (!cond || (root && !hierarchy_used)) | |
7d74b06f | 806 | return NULL; |
14067bb3 | 807 | |
711d3d2c KH |
808 | if (!root) |
809 | root = root_mem_cgroup; | |
810 | ||
7d74b06f KH |
811 | do { |
812 | iter = NULL; | |
14067bb3 | 813 | rcu_read_lock(); |
7d74b06f KH |
814 | |
815 | css = css_get_next(&mem_cgroup_subsys, nextid, | |
816 | &root->css, &found); | |
14067bb3 | 817 | if (css && css_tryget(css)) |
7d74b06f | 818 | iter = container_of(css, struct mem_cgroup, css); |
14067bb3 | 819 | rcu_read_unlock(); |
7d74b06f | 820 | /* If css is NULL, no more cgroups will be found */ |
14067bb3 | 821 | nextid = found + 1; |
7d74b06f | 822 | } while (css && !iter); |
14067bb3 | 823 | |
7d74b06f | 824 | return iter; |
14067bb3 | 825 | } |
7d74b06f KH |
826 | /* |
827 | * for_eacn_mem_cgroup_tree() for visiting all cgroup under tree. Please | |
828 | * be careful that "break" loop is not allowed. We have reference count. | |
829 | * Instead of that modify "cond" to be false and "continue" to exit the loop. | |
830 | */ | |
831 | #define for_each_mem_cgroup_tree_cond(iter, root, cond) \ | |
832 | for (iter = mem_cgroup_start_loop(root);\ | |
833 | iter != NULL;\ | |
834 | iter = mem_cgroup_get_next(iter, root, cond)) | |
835 | ||
836 | #define for_each_mem_cgroup_tree(iter, root) \ | |
837 | for_each_mem_cgroup_tree_cond(iter, root, true) | |
838 | ||
711d3d2c KH |
839 | #define for_each_mem_cgroup_all(iter) \ |
840 | for_each_mem_cgroup_tree_cond(iter, NULL, true) | |
841 | ||
14067bb3 | 842 | |
4b3bde4c BS |
843 | static inline bool mem_cgroup_is_root(struct mem_cgroup *mem) |
844 | { | |
845 | return (mem == root_mem_cgroup); | |
846 | } | |
847 | ||
456f998e YH |
848 | void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) |
849 | { | |
850 | struct mem_cgroup *mem; | |
851 | ||
852 | if (!mm) | |
853 | return; | |
854 | ||
855 | rcu_read_lock(); | |
856 | mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); | |
857 | if (unlikely(!mem)) | |
858 | goto out; | |
859 | ||
860 | switch (idx) { | |
861 | case PGMAJFAULT: | |
862 | mem_cgroup_pgmajfault(mem, 1); | |
863 | break; | |
864 | case PGFAULT: | |
865 | mem_cgroup_pgfault(mem, 1); | |
866 | break; | |
867 | default: | |
868 | BUG(); | |
869 | } | |
870 | out: | |
871 | rcu_read_unlock(); | |
872 | } | |
873 | EXPORT_SYMBOL(mem_cgroup_count_vm_event); | |
874 | ||
08e552c6 KH |
875 | /* |
876 | * Following LRU functions are allowed to be used without PCG_LOCK. | |
877 | * Operations are called by routine of global LRU independently from memcg. | |
878 | * What we have to take care of here is validness of pc->mem_cgroup. | |
879 | * | |
880 | * Changes to pc->mem_cgroup happens when | |
881 | * 1. charge | |
882 | * 2. moving account | |
883 | * In typical case, "charge" is done before add-to-lru. Exception is SwapCache. | |
884 | * It is added to LRU before charge. | |
885 | * If PCG_USED bit is not set, page_cgroup is not added to this private LRU. | |
886 | * When moving account, the page is not on LRU. It's isolated. | |
887 | */ | |
4f98a2fe | 888 | |
08e552c6 KH |
889 | void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru) |
890 | { | |
891 | struct page_cgroup *pc; | |
08e552c6 | 892 | struct mem_cgroup_per_zone *mz; |
6d12e2d8 | 893 | |
f8d66542 | 894 | if (mem_cgroup_disabled()) |
08e552c6 KH |
895 | return; |
896 | pc = lookup_page_cgroup(page); | |
897 | /* can happen while we handle swapcache. */ | |
4b3bde4c | 898 | if (!TestClearPageCgroupAcctLRU(pc)) |
08e552c6 | 899 | return; |
4b3bde4c | 900 | VM_BUG_ON(!pc->mem_cgroup); |
544122e5 KH |
901 | /* |
902 | * We don't check PCG_USED bit. It's cleared when the "page" is finally | |
903 | * removed from global LRU. | |
904 | */ | |
97a6c37b | 905 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
ece35ca8 KH |
906 | /* huge page split is done under lru_lock. so, we have no races. */ |
907 | MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page); | |
4b3bde4c BS |
908 | if (mem_cgroup_is_root(pc->mem_cgroup)) |
909 | return; | |
910 | VM_BUG_ON(list_empty(&pc->lru)); | |
08e552c6 | 911 | list_del_init(&pc->lru); |
6d12e2d8 KH |
912 | } |
913 | ||
08e552c6 | 914 | void mem_cgroup_del_lru(struct page *page) |
6d12e2d8 | 915 | { |
08e552c6 KH |
916 | mem_cgroup_del_lru_list(page, page_lru(page)); |
917 | } | |
b69408e8 | 918 | |
3f58a829 MK |
919 | /* |
920 | * Writeback is about to end against a page which has been marked for immediate | |
921 | * reclaim. If it still appears to be reclaimable, move it to the tail of the | |
922 | * inactive list. | |
923 | */ | |
924 | void mem_cgroup_rotate_reclaimable_page(struct page *page) | |
925 | { | |
926 | struct mem_cgroup_per_zone *mz; | |
927 | struct page_cgroup *pc; | |
928 | enum lru_list lru = page_lru(page); | |
929 | ||
930 | if (mem_cgroup_disabled()) | |
931 | return; | |
932 | ||
933 | pc = lookup_page_cgroup(page); | |
934 | /* unused or root page is not rotated. */ | |
935 | if (!PageCgroupUsed(pc)) | |
936 | return; | |
937 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ | |
938 | smp_rmb(); | |
939 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
940 | return; | |
97a6c37b | 941 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
3f58a829 MK |
942 | list_move_tail(&pc->lru, &mz->lists[lru]); |
943 | } | |
944 | ||
08e552c6 KH |
945 | void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru) |
946 | { | |
947 | struct mem_cgroup_per_zone *mz; | |
948 | struct page_cgroup *pc; | |
b69408e8 | 949 | |
f8d66542 | 950 | if (mem_cgroup_disabled()) |
08e552c6 | 951 | return; |
6d12e2d8 | 952 | |
08e552c6 | 953 | pc = lookup_page_cgroup(page); |
4b3bde4c | 954 | /* unused or root page is not rotated. */ |
713735b4 JW |
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)) | |
08e552c6 | 960 | return; |
97a6c37b | 961 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
08e552c6 | 962 | list_move(&pc->lru, &mz->lists[lru]); |
6d12e2d8 KH |
963 | } |
964 | ||
08e552c6 | 965 | void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru) |
66e1707b | 966 | { |
08e552c6 KH |
967 | struct page_cgroup *pc; |
968 | struct mem_cgroup_per_zone *mz; | |
6d12e2d8 | 969 | |
f8d66542 | 970 | if (mem_cgroup_disabled()) |
08e552c6 KH |
971 | return; |
972 | pc = lookup_page_cgroup(page); | |
4b3bde4c | 973 | VM_BUG_ON(PageCgroupAcctLRU(pc)); |
08e552c6 | 974 | if (!PageCgroupUsed(pc)) |
894bc310 | 975 | return; |
713735b4 JW |
976 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
977 | smp_rmb(); | |
97a6c37b | 978 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
ece35ca8 KH |
979 | /* huge page split is done under lru_lock. so, we have no races. */ |
980 | MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page); | |
4b3bde4c BS |
981 | SetPageCgroupAcctLRU(pc); |
982 | if (mem_cgroup_is_root(pc->mem_cgroup)) | |
983 | return; | |
08e552c6 KH |
984 | list_add(&pc->lru, &mz->lists[lru]); |
985 | } | |
544122e5 | 986 | |
08e552c6 | 987 | /* |
5a6475a4 KH |
988 | * At handling SwapCache and other FUSE stuff, pc->mem_cgroup may be changed |
989 | * while it's linked to lru because the page may be reused after it's fully | |
990 | * uncharged. To handle that, unlink page_cgroup from LRU when charge it again. | |
991 | * It's done under lock_page and expected that zone->lru_lock isnever held. | |
08e552c6 | 992 | */ |
5a6475a4 | 993 | static void mem_cgroup_lru_del_before_commit(struct page *page) |
08e552c6 | 994 | { |
544122e5 KH |
995 | unsigned long flags; |
996 | struct zone *zone = page_zone(page); | |
997 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
998 | ||
5a6475a4 KH |
999 | /* |
1000 | * Doing this check without taking ->lru_lock seems wrong but this | |
1001 | * is safe. Because if page_cgroup's USED bit is unset, the page | |
1002 | * will not be added to any memcg's LRU. If page_cgroup's USED bit is | |
1003 | * set, the commit after this will fail, anyway. | |
1004 | * This all charge/uncharge is done under some mutual execustion. | |
1005 | * So, we don't need to taking care of changes in USED bit. | |
1006 | */ | |
1007 | if (likely(!PageLRU(page))) | |
1008 | return; | |
1009 | ||
544122e5 KH |
1010 | spin_lock_irqsave(&zone->lru_lock, flags); |
1011 | /* | |
1012 | * Forget old LRU when this page_cgroup is *not* used. This Used bit | |
1013 | * is guarded by lock_page() because the page is SwapCache. | |
1014 | */ | |
1015 | if (!PageCgroupUsed(pc)) | |
1016 | mem_cgroup_del_lru_list(page, page_lru(page)); | |
1017 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
08e552c6 KH |
1018 | } |
1019 | ||
5a6475a4 | 1020 | static void mem_cgroup_lru_add_after_commit(struct page *page) |
544122e5 KH |
1021 | { |
1022 | unsigned long flags; | |
1023 | struct zone *zone = page_zone(page); | |
1024 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
1025 | ||
5a6475a4 KH |
1026 | /* taking care of that the page is added to LRU while we commit it */ |
1027 | if (likely(!PageLRU(page))) | |
1028 | return; | |
544122e5 KH |
1029 | spin_lock_irqsave(&zone->lru_lock, flags); |
1030 | /* link when the page is linked to LRU but page_cgroup isn't */ | |
4b3bde4c | 1031 | if (PageLRU(page) && !PageCgroupAcctLRU(pc)) |
544122e5 KH |
1032 | mem_cgroup_add_lru_list(page, page_lru(page)); |
1033 | spin_unlock_irqrestore(&zone->lru_lock, flags); | |
1034 | } | |
1035 | ||
1036 | ||
08e552c6 KH |
1037 | void mem_cgroup_move_lists(struct page *page, |
1038 | enum lru_list from, enum lru_list to) | |
1039 | { | |
f8d66542 | 1040 | if (mem_cgroup_disabled()) |
08e552c6 KH |
1041 | return; |
1042 | mem_cgroup_del_lru_list(page, from); | |
1043 | mem_cgroup_add_lru_list(page, to); | |
66e1707b BS |
1044 | } |
1045 | ||
4c4a2214 DR |
1046 | int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem) |
1047 | { | |
1048 | int ret; | |
0b7f569e | 1049 | struct mem_cgroup *curr = NULL; |
158e0a2d | 1050 | struct task_struct *p; |
4c4a2214 | 1051 | |
158e0a2d KH |
1052 | p = find_lock_task_mm(task); |
1053 | if (!p) | |
1054 | return 0; | |
1055 | curr = try_get_mem_cgroup_from_mm(p->mm); | |
1056 | task_unlock(p); | |
0b7f569e KH |
1057 | if (!curr) |
1058 | return 0; | |
d31f56db DN |
1059 | /* |
1060 | * We should check use_hierarchy of "mem" not "curr". Because checking | |
1061 | * use_hierarchy of "curr" here make this function true if hierarchy is | |
1062 | * enabled in "curr" and "curr" is a child of "mem" in *cgroup* | |
1063 | * hierarchy(even if use_hierarchy is disabled in "mem"). | |
1064 | */ | |
1065 | if (mem->use_hierarchy) | |
0b7f569e KH |
1066 | ret = css_is_ancestor(&curr->css, &mem->css); |
1067 | else | |
1068 | ret = (curr == mem); | |
1069 | css_put(&curr->css); | |
4c4a2214 DR |
1070 | return ret; |
1071 | } | |
1072 | ||
c772be93 | 1073 | static int calc_inactive_ratio(struct mem_cgroup *memcg, unsigned long *present_pages) |
14797e23 KM |
1074 | { |
1075 | unsigned long active; | |
1076 | unsigned long inactive; | |
c772be93 KM |
1077 | unsigned long gb; |
1078 | unsigned long inactive_ratio; | |
14797e23 | 1079 | |
14067bb3 KH |
1080 | inactive = mem_cgroup_get_local_zonestat(memcg, LRU_INACTIVE_ANON); |
1081 | active = mem_cgroup_get_local_zonestat(memcg, LRU_ACTIVE_ANON); | |
14797e23 | 1082 | |
c772be93 KM |
1083 | gb = (inactive + active) >> (30 - PAGE_SHIFT); |
1084 | if (gb) | |
1085 | inactive_ratio = int_sqrt(10 * gb); | |
1086 | else | |
1087 | inactive_ratio = 1; | |
1088 | ||
1089 | if (present_pages) { | |
1090 | present_pages[0] = inactive; | |
1091 | present_pages[1] = active; | |
1092 | } | |
1093 | ||
1094 | return inactive_ratio; | |
1095 | } | |
1096 | ||
1097 | int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg) | |
1098 | { | |
1099 | unsigned long active; | |
1100 | unsigned long inactive; | |
1101 | unsigned long present_pages[2]; | |
1102 | unsigned long inactive_ratio; | |
1103 | ||
1104 | inactive_ratio = calc_inactive_ratio(memcg, present_pages); | |
1105 | ||
1106 | inactive = present_pages[0]; | |
1107 | active = present_pages[1]; | |
1108 | ||
1109 | if (inactive * inactive_ratio < active) | |
14797e23 KM |
1110 | return 1; |
1111 | ||
1112 | return 0; | |
1113 | } | |
1114 | ||
56e49d21 RR |
1115 | int mem_cgroup_inactive_file_is_low(struct mem_cgroup *memcg) |
1116 | { | |
1117 | unsigned long active; | |
1118 | unsigned long inactive; | |
1119 | ||
1120 | inactive = mem_cgroup_get_local_zonestat(memcg, LRU_INACTIVE_FILE); | |
1121 | active = mem_cgroup_get_local_zonestat(memcg, LRU_ACTIVE_FILE); | |
1122 | ||
1123 | return (active > inactive); | |
1124 | } | |
1125 | ||
1bac180b YH |
1126 | unsigned long mem_cgroup_zone_nr_lru_pages(struct mem_cgroup *memcg, |
1127 | struct zone *zone, | |
1128 | enum lru_list lru) | |
a3d8e054 | 1129 | { |
13d7e3a2 | 1130 | int nid = zone_to_nid(zone); |
a3d8e054 KM |
1131 | int zid = zone_idx(zone); |
1132 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
1133 | ||
1134 | return MEM_CGROUP_ZSTAT(mz, lru); | |
1135 | } | |
1136 | ||
406eb0c9 YH |
1137 | static unsigned long mem_cgroup_node_nr_file_lru_pages(struct mem_cgroup *memcg, |
1138 | int nid) | |
1139 | { | |
1140 | unsigned long ret; | |
1141 | ||
1142 | ret = mem_cgroup_get_zonestat_node(memcg, nid, LRU_INACTIVE_FILE) + | |
1143 | mem_cgroup_get_zonestat_node(memcg, nid, LRU_ACTIVE_FILE); | |
1144 | ||
1145 | return ret; | |
1146 | } | |
1147 | ||
4d0c066d KH |
1148 | static unsigned long mem_cgroup_node_nr_anon_lru_pages(struct mem_cgroup *memcg, |
1149 | int nid) | |
1150 | { | |
1151 | unsigned long ret; | |
1152 | ||
1153 | ret = mem_cgroup_get_zonestat_node(memcg, nid, LRU_INACTIVE_ANON) + | |
1154 | mem_cgroup_get_zonestat_node(memcg, nid, LRU_ACTIVE_ANON); | |
1155 | return ret; | |
1156 | } | |
1157 | ||
1158 | #if MAX_NUMNODES > 1 | |
406eb0c9 YH |
1159 | static unsigned long mem_cgroup_nr_file_lru_pages(struct mem_cgroup *memcg) |
1160 | { | |
1161 | u64 total = 0; | |
1162 | int nid; | |
1163 | ||
1164 | for_each_node_state(nid, N_HIGH_MEMORY) | |
1165 | total += mem_cgroup_node_nr_file_lru_pages(memcg, nid); | |
1166 | ||
1167 | return total; | |
1168 | } | |
1169 | ||
406eb0c9 YH |
1170 | static unsigned long mem_cgroup_nr_anon_lru_pages(struct mem_cgroup *memcg) |
1171 | { | |
1172 | u64 total = 0; | |
1173 | int nid; | |
1174 | ||
1175 | for_each_node_state(nid, N_HIGH_MEMORY) | |
1176 | total += mem_cgroup_node_nr_anon_lru_pages(memcg, nid); | |
1177 | ||
1178 | return total; | |
1179 | } | |
1180 | ||
1181 | static unsigned long | |
1182 | mem_cgroup_node_nr_unevictable_lru_pages(struct mem_cgroup *memcg, int nid) | |
1183 | { | |
1184 | return mem_cgroup_get_zonestat_node(memcg, nid, LRU_UNEVICTABLE); | |
1185 | } | |
1186 | ||
1187 | static unsigned long | |
1188 | mem_cgroup_nr_unevictable_lru_pages(struct mem_cgroup *memcg) | |
1189 | { | |
1190 | u64 total = 0; | |
1191 | int nid; | |
1192 | ||
1193 | for_each_node_state(nid, N_HIGH_MEMORY) | |
1194 | total += mem_cgroup_node_nr_unevictable_lru_pages(memcg, nid); | |
1195 | ||
1196 | return total; | |
1197 | } | |
1198 | ||
1199 | static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, | |
1200 | int nid) | |
1201 | { | |
1202 | enum lru_list l; | |
1203 | u64 total = 0; | |
1204 | ||
1205 | for_each_lru(l) | |
1206 | total += mem_cgroup_get_zonestat_node(memcg, nid, l); | |
1207 | ||
1208 | return total; | |
1209 | } | |
1210 | ||
1211 | static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg) | |
1212 | { | |
1213 | u64 total = 0; | |
1214 | int nid; | |
1215 | ||
1216 | for_each_node_state(nid, N_HIGH_MEMORY) | |
1217 | total += mem_cgroup_node_nr_lru_pages(memcg, nid); | |
1218 | ||
1219 | return total; | |
1220 | } | |
1221 | #endif /* CONFIG_NUMA */ | |
1222 | ||
3e2f41f1 KM |
1223 | struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg, |
1224 | struct zone *zone) | |
1225 | { | |
13d7e3a2 | 1226 | int nid = zone_to_nid(zone); |
3e2f41f1 KM |
1227 | int zid = zone_idx(zone); |
1228 | struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); | |
1229 | ||
1230 | return &mz->reclaim_stat; | |
1231 | } | |
1232 | ||
1233 | struct zone_reclaim_stat * | |
1234 | mem_cgroup_get_reclaim_stat_from_page(struct page *page) | |
1235 | { | |
1236 | struct page_cgroup *pc; | |
1237 | struct mem_cgroup_per_zone *mz; | |
1238 | ||
1239 | if (mem_cgroup_disabled()) | |
1240 | return NULL; | |
1241 | ||
1242 | pc = lookup_page_cgroup(page); | |
bd112db8 DN |
1243 | if (!PageCgroupUsed(pc)) |
1244 | return NULL; | |
713735b4 JW |
1245 | /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ |
1246 | smp_rmb(); | |
97a6c37b | 1247 | mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); |
3e2f41f1 KM |
1248 | return &mz->reclaim_stat; |
1249 | } | |
1250 | ||
66e1707b BS |
1251 | unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, |
1252 | struct list_head *dst, | |
1253 | unsigned long *scanned, int order, | |
1254 | int mode, struct zone *z, | |
1255 | struct mem_cgroup *mem_cont, | |
4f98a2fe | 1256 | int active, int file) |
66e1707b BS |
1257 | { |
1258 | unsigned long nr_taken = 0; | |
1259 | struct page *page; | |
1260 | unsigned long scan; | |
1261 | LIST_HEAD(pc_list); | |
1262 | struct list_head *src; | |
ff7283fa | 1263 | struct page_cgroup *pc, *tmp; |
13d7e3a2 | 1264 | int nid = zone_to_nid(z); |
1ecaab2b KH |
1265 | int zid = zone_idx(z); |
1266 | struct mem_cgroup_per_zone *mz; | |
b7c46d15 | 1267 | int lru = LRU_FILE * file + active; |
2ffebca6 | 1268 | int ret; |
66e1707b | 1269 | |
cf475ad2 | 1270 | BUG_ON(!mem_cont); |
1ecaab2b | 1271 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); |
b69408e8 | 1272 | src = &mz->lists[lru]; |
66e1707b | 1273 | |
ff7283fa KH |
1274 | scan = 0; |
1275 | list_for_each_entry_safe_reverse(pc, tmp, src, lru) { | |
436c6541 | 1276 | if (scan >= nr_to_scan) |
ff7283fa | 1277 | break; |
08e552c6 | 1278 | |
52d4b9ac KH |
1279 | if (unlikely(!PageCgroupUsed(pc))) |
1280 | continue; | |
5564e88b | 1281 | |
6b3ae58e | 1282 | page = lookup_cgroup_page(pc); |
5564e88b | 1283 | |
436c6541 | 1284 | if (unlikely(!PageLRU(page))) |
ff7283fa | 1285 | continue; |
ff7283fa | 1286 | |
436c6541 | 1287 | scan++; |
2ffebca6 KH |
1288 | ret = __isolate_lru_page(page, mode, file); |
1289 | switch (ret) { | |
1290 | case 0: | |
66e1707b | 1291 | list_move(&page->lru, dst); |
2ffebca6 | 1292 | mem_cgroup_del_lru(page); |
2c888cfb | 1293 | nr_taken += hpage_nr_pages(page); |
2ffebca6 KH |
1294 | break; |
1295 | case -EBUSY: | |
1296 | /* we don't affect global LRU but rotate in our LRU */ | |
1297 | mem_cgroup_rotate_lru_list(page, page_lru(page)); | |
1298 | break; | |
1299 | default: | |
1300 | break; | |
66e1707b BS |
1301 | } |
1302 | } | |
1303 | ||
66e1707b | 1304 | *scanned = scan; |
cc8e970c KM |
1305 | |
1306 | trace_mm_vmscan_memcg_isolate(0, nr_to_scan, scan, nr_taken, | |
1307 | 0, 0, 0, mode); | |
1308 | ||
66e1707b BS |
1309 | return nr_taken; |
1310 | } | |
1311 | ||
6d61ef40 BS |
1312 | #define mem_cgroup_from_res_counter(counter, member) \ |
1313 | container_of(counter, struct mem_cgroup, member) | |
1314 | ||
19942822 | 1315 | /** |
9d11ea9f JW |
1316 | * mem_cgroup_margin - calculate chargeable space of a memory cgroup |
1317 | * @mem: the memory cgroup | |
19942822 | 1318 | * |
9d11ea9f | 1319 | * Returns the maximum amount of memory @mem can be charged with, in |
7ec99d62 | 1320 | * pages. |
19942822 | 1321 | */ |
7ec99d62 | 1322 | static unsigned long mem_cgroup_margin(struct mem_cgroup *mem) |
19942822 | 1323 | { |
9d11ea9f JW |
1324 | unsigned long long margin; |
1325 | ||
1326 | margin = res_counter_margin(&mem->res); | |
1327 | if (do_swap_account) | |
1328 | margin = min(margin, res_counter_margin(&mem->memsw)); | |
7ec99d62 | 1329 | return margin >> PAGE_SHIFT; |
19942822 JW |
1330 | } |
1331 | ||
a7885eb8 KM |
1332 | static unsigned int get_swappiness(struct mem_cgroup *memcg) |
1333 | { | |
1334 | struct cgroup *cgrp = memcg->css.cgroup; | |
a7885eb8 KM |
1335 | |
1336 | /* root ? */ | |
1337 | if (cgrp->parent == NULL) | |
1338 | return vm_swappiness; | |
1339 | ||
bf1ff263 | 1340 | return memcg->swappiness; |
a7885eb8 KM |
1341 | } |
1342 | ||
32047e2a KH |
1343 | static void mem_cgroup_start_move(struct mem_cgroup *mem) |
1344 | { | |
1345 | int cpu; | |
1489ebad KH |
1346 | |
1347 | get_online_cpus(); | |
1348 | spin_lock(&mem->pcp_counter_lock); | |
1349 | for_each_online_cpu(cpu) | |
32047e2a | 1350 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) += 1; |
1489ebad KH |
1351 | mem->nocpu_base.count[MEM_CGROUP_ON_MOVE] += 1; |
1352 | spin_unlock(&mem->pcp_counter_lock); | |
1353 | put_online_cpus(); | |
32047e2a KH |
1354 | |
1355 | synchronize_rcu(); | |
1356 | } | |
1357 | ||
1358 | static void mem_cgroup_end_move(struct mem_cgroup *mem) | |
1359 | { | |
1360 | int cpu; | |
1361 | ||
1362 | if (!mem) | |
1363 | return; | |
1489ebad KH |
1364 | get_online_cpus(); |
1365 | spin_lock(&mem->pcp_counter_lock); | |
1366 | for_each_online_cpu(cpu) | |
32047e2a | 1367 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) -= 1; |
1489ebad KH |
1368 | mem->nocpu_base.count[MEM_CGROUP_ON_MOVE] -= 1; |
1369 | spin_unlock(&mem->pcp_counter_lock); | |
1370 | put_online_cpus(); | |
32047e2a KH |
1371 | } |
1372 | /* | |
1373 | * 2 routines for checking "mem" is under move_account() or not. | |
1374 | * | |
1375 | * mem_cgroup_stealed() - checking a cgroup is mc.from or not. This is used | |
1376 | * for avoiding race in accounting. If true, | |
1377 | * pc->mem_cgroup may be overwritten. | |
1378 | * | |
1379 | * mem_cgroup_under_move() - checking a cgroup is mc.from or mc.to or | |
1380 | * under hierarchy of moving cgroups. This is for | |
1381 | * waiting at hith-memory prressure caused by "move". | |
1382 | */ | |
1383 | ||
1384 | static bool mem_cgroup_stealed(struct mem_cgroup *mem) | |
1385 | { | |
1386 | VM_BUG_ON(!rcu_read_lock_held()); | |
1387 | return this_cpu_read(mem->stat->count[MEM_CGROUP_ON_MOVE]) > 0; | |
1388 | } | |
4b534334 KH |
1389 | |
1390 | static bool mem_cgroup_under_move(struct mem_cgroup *mem) | |
1391 | { | |
2bd9bb20 KH |
1392 | struct mem_cgroup *from; |
1393 | struct mem_cgroup *to; | |
4b534334 | 1394 | bool ret = false; |
2bd9bb20 KH |
1395 | /* |
1396 | * Unlike task_move routines, we access mc.to, mc.from not under | |
1397 | * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. | |
1398 | */ | |
1399 | spin_lock(&mc.lock); | |
1400 | from = mc.from; | |
1401 | to = mc.to; | |
1402 | if (!from) | |
1403 | goto unlock; | |
1404 | if (from == mem || to == mem | |
1405 | || (mem->use_hierarchy && css_is_ancestor(&from->css, &mem->css)) | |
1406 | || (mem->use_hierarchy && css_is_ancestor(&to->css, &mem->css))) | |
1407 | ret = true; | |
1408 | unlock: | |
1409 | spin_unlock(&mc.lock); | |
4b534334 KH |
1410 | return ret; |
1411 | } | |
1412 | ||
1413 | static bool mem_cgroup_wait_acct_move(struct mem_cgroup *mem) | |
1414 | { | |
1415 | if (mc.moving_task && current != mc.moving_task) { | |
1416 | if (mem_cgroup_under_move(mem)) { | |
1417 | DEFINE_WAIT(wait); | |
1418 | prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); | |
1419 | /* moving charge context might have finished. */ | |
1420 | if (mc.moving_task) | |
1421 | schedule(); | |
1422 | finish_wait(&mc.waitq, &wait); | |
1423 | return true; | |
1424 | } | |
1425 | } | |
1426 | return false; | |
1427 | } | |
1428 | ||
e222432b | 1429 | /** |
6a6135b6 | 1430 | * mem_cgroup_print_oom_info: Called from OOM with tasklist_lock held in read mode. |
e222432b BS |
1431 | * @memcg: The memory cgroup that went over limit |
1432 | * @p: Task that is going to be killed | |
1433 | * | |
1434 | * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is | |
1435 | * enabled | |
1436 | */ | |
1437 | void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) | |
1438 | { | |
1439 | struct cgroup *task_cgrp; | |
1440 | struct cgroup *mem_cgrp; | |
1441 | /* | |
1442 | * Need a buffer in BSS, can't rely on allocations. The code relies | |
1443 | * on the assumption that OOM is serialized for memory controller. | |
1444 | * If this assumption is broken, revisit this code. | |
1445 | */ | |
1446 | static char memcg_name[PATH_MAX]; | |
1447 | int ret; | |
1448 | ||
d31f56db | 1449 | if (!memcg || !p) |
e222432b BS |
1450 | return; |
1451 | ||
1452 | ||
1453 | rcu_read_lock(); | |
1454 | ||
1455 | mem_cgrp = memcg->css.cgroup; | |
1456 | task_cgrp = task_cgroup(p, mem_cgroup_subsys_id); | |
1457 | ||
1458 | ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX); | |
1459 | if (ret < 0) { | |
1460 | /* | |
1461 | * Unfortunately, we are unable to convert to a useful name | |
1462 | * But we'll still print out the usage information | |
1463 | */ | |
1464 | rcu_read_unlock(); | |
1465 | goto done; | |
1466 | } | |
1467 | rcu_read_unlock(); | |
1468 | ||
1469 | printk(KERN_INFO "Task in %s killed", memcg_name); | |
1470 | ||
1471 | rcu_read_lock(); | |
1472 | ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX); | |
1473 | if (ret < 0) { | |
1474 | rcu_read_unlock(); | |
1475 | goto done; | |
1476 | } | |
1477 | rcu_read_unlock(); | |
1478 | ||
1479 | /* | |
1480 | * Continues from above, so we don't need an KERN_ level | |
1481 | */ | |
1482 | printk(KERN_CONT " as a result of limit of %s\n", memcg_name); | |
1483 | done: | |
1484 | ||
1485 | printk(KERN_INFO "memory: usage %llukB, limit %llukB, failcnt %llu\n", | |
1486 | res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, | |
1487 | res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, | |
1488 | res_counter_read_u64(&memcg->res, RES_FAILCNT)); | |
1489 | printk(KERN_INFO "memory+swap: usage %llukB, limit %llukB, " | |
1490 | "failcnt %llu\n", | |
1491 | res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, | |
1492 | res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, | |
1493 | res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); | |
1494 | } | |
1495 | ||
81d39c20 KH |
1496 | /* |
1497 | * This function returns the number of memcg under hierarchy tree. Returns | |
1498 | * 1(self count) if no children. | |
1499 | */ | |
1500 | static int mem_cgroup_count_children(struct mem_cgroup *mem) | |
1501 | { | |
1502 | int num = 0; | |
7d74b06f KH |
1503 | struct mem_cgroup *iter; |
1504 | ||
1505 | for_each_mem_cgroup_tree(iter, mem) | |
1506 | num++; | |
81d39c20 KH |
1507 | return num; |
1508 | } | |
1509 | ||
a63d83f4 DR |
1510 | /* |
1511 | * Return the memory (and swap, if configured) limit for a memcg. | |
1512 | */ | |
1513 | u64 mem_cgroup_get_limit(struct mem_cgroup *memcg) | |
1514 | { | |
1515 | u64 limit; | |
1516 | u64 memsw; | |
1517 | ||
f3e8eb70 JW |
1518 | limit = res_counter_read_u64(&memcg->res, RES_LIMIT); |
1519 | limit += total_swap_pages << PAGE_SHIFT; | |
1520 | ||
a63d83f4 DR |
1521 | memsw = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
1522 | /* | |
1523 | * If memsw is finite and limits the amount of swap space available | |
1524 | * to this memcg, return that limit. | |
1525 | */ | |
1526 | return min(limit, memsw); | |
1527 | } | |
1528 | ||
6d61ef40 | 1529 | /* |
04046e1a KH |
1530 | * Visit the first child (need not be the first child as per the ordering |
1531 | * of the cgroup list, since we track last_scanned_child) of @mem and use | |
1532 | * that to reclaim free pages from. | |
1533 | */ | |
1534 | static struct mem_cgroup * | |
1535 | mem_cgroup_select_victim(struct mem_cgroup *root_mem) | |
1536 | { | |
1537 | struct mem_cgroup *ret = NULL; | |
1538 | struct cgroup_subsys_state *css; | |
1539 | int nextid, found; | |
1540 | ||
1541 | if (!root_mem->use_hierarchy) { | |
1542 | css_get(&root_mem->css); | |
1543 | ret = root_mem; | |
1544 | } | |
1545 | ||
1546 | while (!ret) { | |
1547 | rcu_read_lock(); | |
1548 | nextid = root_mem->last_scanned_child + 1; | |
1549 | css = css_get_next(&mem_cgroup_subsys, nextid, &root_mem->css, | |
1550 | &found); | |
1551 | if (css && css_tryget(css)) | |
1552 | ret = container_of(css, struct mem_cgroup, css); | |
1553 | ||
1554 | rcu_read_unlock(); | |
1555 | /* Updates scanning parameter */ | |
04046e1a KH |
1556 | if (!css) { |
1557 | /* this means start scan from ID:1 */ | |
1558 | root_mem->last_scanned_child = 0; | |
1559 | } else | |
1560 | root_mem->last_scanned_child = found; | |
04046e1a KH |
1561 | } |
1562 | ||
1563 | return ret; | |
1564 | } | |
1565 | ||
4d0c066d KH |
1566 | /** |
1567 | * test_mem_cgroup_node_reclaimable | |
1568 | * @mem: the target memcg | |
1569 | * @nid: the node ID to be checked. | |
1570 | * @noswap : specify true here if the user wants flle only information. | |
1571 | * | |
1572 | * This function returns whether the specified memcg contains any | |
1573 | * reclaimable pages on a node. Returns true if there are any reclaimable | |
1574 | * pages in the node. | |
1575 | */ | |
1576 | static bool test_mem_cgroup_node_reclaimable(struct mem_cgroup *mem, | |
1577 | int nid, bool noswap) | |
1578 | { | |
1579 | if (mem_cgroup_node_nr_file_lru_pages(mem, nid)) | |
1580 | return true; | |
1581 | if (noswap || !total_swap_pages) | |
1582 | return false; | |
1583 | if (mem_cgroup_node_nr_anon_lru_pages(mem, nid)) | |
1584 | return true; | |
1585 | return false; | |
1586 | ||
1587 | } | |
889976db YH |
1588 | #if MAX_NUMNODES > 1 |
1589 | ||
1590 | /* | |
1591 | * Always updating the nodemask is not very good - even if we have an empty | |
1592 | * list or the wrong list here, we can start from some node and traverse all | |
1593 | * nodes based on the zonelist. So update the list loosely once per 10 secs. | |
1594 | * | |
1595 | */ | |
1596 | static void mem_cgroup_may_update_nodemask(struct mem_cgroup *mem) | |
1597 | { | |
1598 | int nid; | |
453a9bf3 KH |
1599 | /* |
1600 | * numainfo_events > 0 means there was at least NUMAINFO_EVENTS_TARGET | |
1601 | * pagein/pageout changes since the last update. | |
1602 | */ | |
1603 | if (!atomic_read(&mem->numainfo_events)) | |
1604 | return; | |
1605 | if (atomic_inc_return(&mem->numainfo_updating) > 1) | |
889976db YH |
1606 | return; |
1607 | ||
889976db YH |
1608 | /* make a nodemask where this memcg uses memory from */ |
1609 | mem->scan_nodes = node_states[N_HIGH_MEMORY]; | |
1610 | ||
1611 | for_each_node_mask(nid, node_states[N_HIGH_MEMORY]) { | |
1612 | ||
4d0c066d KH |
1613 | if (!test_mem_cgroup_node_reclaimable(mem, nid, false)) |
1614 | node_clear(nid, mem->scan_nodes); | |
889976db | 1615 | } |
453a9bf3 KH |
1616 | |
1617 | atomic_set(&mem->numainfo_events, 0); | |
1618 | atomic_set(&mem->numainfo_updating, 0); | |
889976db YH |
1619 | } |
1620 | ||
1621 | /* | |
1622 | * Selecting a node where we start reclaim from. Because what we need is just | |
1623 | * reducing usage counter, start from anywhere is O,K. Considering | |
1624 | * memory reclaim from current node, there are pros. and cons. | |
1625 | * | |
1626 | * Freeing memory from current node means freeing memory from a node which | |
1627 | * we'll use or we've used. So, it may make LRU bad. And if several threads | |
1628 | * hit limits, it will see a contention on a node. But freeing from remote | |
1629 | * node means more costs for memory reclaim because of memory latency. | |
1630 | * | |
1631 | * Now, we use round-robin. Better algorithm is welcomed. | |
1632 | */ | |
1633 | int mem_cgroup_select_victim_node(struct mem_cgroup *mem) | |
1634 | { | |
1635 | int node; | |
1636 | ||
1637 | mem_cgroup_may_update_nodemask(mem); | |
1638 | node = mem->last_scanned_node; | |
1639 | ||
1640 | node = next_node(node, mem->scan_nodes); | |
1641 | if (node == MAX_NUMNODES) | |
1642 | node = first_node(mem->scan_nodes); | |
1643 | /* | |
1644 | * We call this when we hit limit, not when pages are added to LRU. | |
1645 | * No LRU may hold pages because all pages are UNEVICTABLE or | |
1646 | * memcg is too small and all pages are not on LRU. In that case, | |
1647 | * we use curret node. | |
1648 | */ | |
1649 | if (unlikely(node == MAX_NUMNODES)) | |
1650 | node = numa_node_id(); | |
1651 | ||
1652 | mem->last_scanned_node = node; | |
1653 | return node; | |
1654 | } | |
1655 | ||
4d0c066d KH |
1656 | /* |
1657 | * Check all nodes whether it contains reclaimable pages or not. | |
1658 | * For quick scan, we make use of scan_nodes. This will allow us to skip | |
1659 | * unused nodes. But scan_nodes is lazily updated and may not cotain | |
1660 | * enough new information. We need to do double check. | |
1661 | */ | |
1662 | bool mem_cgroup_reclaimable(struct mem_cgroup *mem, bool noswap) | |
1663 | { | |
1664 | int nid; | |
1665 | ||
1666 | /* | |
1667 | * quick check...making use of scan_node. | |
1668 | * We can skip unused nodes. | |
1669 | */ | |
1670 | if (!nodes_empty(mem->scan_nodes)) { | |
1671 | for (nid = first_node(mem->scan_nodes); | |
1672 | nid < MAX_NUMNODES; | |
1673 | nid = next_node(nid, mem->scan_nodes)) { | |
1674 | ||
1675 | if (test_mem_cgroup_node_reclaimable(mem, nid, noswap)) | |
1676 | return true; | |
1677 | } | |
1678 | } | |
1679 | /* | |
1680 | * Check rest of nodes. | |
1681 | */ | |
1682 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
1683 | if (node_isset(nid, mem->scan_nodes)) | |
1684 | continue; | |
1685 | if (test_mem_cgroup_node_reclaimable(mem, nid, noswap)) | |
1686 | return true; | |
1687 | } | |
1688 | return false; | |
1689 | } | |
1690 | ||
889976db YH |
1691 | #else |
1692 | int mem_cgroup_select_victim_node(struct mem_cgroup *mem) | |
1693 | { | |
1694 | return 0; | |
1695 | } | |
4d0c066d KH |
1696 | |
1697 | bool mem_cgroup_reclaimable(struct mem_cgroup *mem, bool noswap) | |
1698 | { | |
1699 | return test_mem_cgroup_node_reclaimable(mem, 0, noswap); | |
1700 | } | |
889976db YH |
1701 | #endif |
1702 | ||
04046e1a KH |
1703 | /* |
1704 | * Scan the hierarchy if needed to reclaim memory. We remember the last child | |
1705 | * we reclaimed from, so that we don't end up penalizing one child extensively | |
1706 | * based on its position in the children list. | |
6d61ef40 BS |
1707 | * |
1708 | * root_mem is the original ancestor that we've been reclaim from. | |
04046e1a KH |
1709 | * |
1710 | * We give up and return to the caller when we visit root_mem twice. | |
1711 | * (other groups can be removed while we're walking....) | |
81d39c20 KH |
1712 | * |
1713 | * If shrink==true, for avoiding to free too much, this returns immedieately. | |
6d61ef40 BS |
1714 | */ |
1715 | static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, | |
4e416953 | 1716 | struct zone *zone, |
75822b44 | 1717 | gfp_t gfp_mask, |
0ae5e89c YH |
1718 | unsigned long reclaim_options, |
1719 | unsigned long *total_scanned) | |
6d61ef40 | 1720 | { |
04046e1a KH |
1721 | struct mem_cgroup *victim; |
1722 | int ret, total = 0; | |
1723 | int loop = 0; | |
75822b44 BS |
1724 | bool noswap = reclaim_options & MEM_CGROUP_RECLAIM_NOSWAP; |
1725 | bool shrink = reclaim_options & MEM_CGROUP_RECLAIM_SHRINK; | |
4e416953 | 1726 | bool check_soft = reclaim_options & MEM_CGROUP_RECLAIM_SOFT; |
9d11ea9f | 1727 | unsigned long excess; |
0ae5e89c | 1728 | unsigned long nr_scanned; |
9d11ea9f JW |
1729 | |
1730 | excess = res_counter_soft_limit_excess(&root_mem->res) >> PAGE_SHIFT; | |
04046e1a | 1731 | |
22a668d7 | 1732 | /* If memsw_is_minimum==1, swap-out is of-no-use. */ |
7ae534d0 | 1733 | if (!check_soft && root_mem->memsw_is_minimum) |
22a668d7 KH |
1734 | noswap = true; |
1735 | ||
4e416953 | 1736 | while (1) { |
04046e1a | 1737 | victim = mem_cgroup_select_victim(root_mem); |
4e416953 | 1738 | if (victim == root_mem) { |
04046e1a | 1739 | loop++; |
fbc29a25 KH |
1740 | /* |
1741 | * We are not draining per cpu cached charges during | |
1742 | * soft limit reclaim because global reclaim doesn't | |
1743 | * care about charges. It tries to free some memory and | |
1744 | * charges will not give any. | |
1745 | */ | |
1746 | if (!check_soft && loop >= 1) | |
26fe6168 | 1747 | drain_all_stock_async(root_mem); |
4e416953 BS |
1748 | if (loop >= 2) { |
1749 | /* | |
1750 | * If we have not been able to reclaim | |
1751 | * anything, it might because there are | |
1752 | * no reclaimable pages under this hierarchy | |
1753 | */ | |
1754 | if (!check_soft || !total) { | |
1755 | css_put(&victim->css); | |
1756 | break; | |
1757 | } | |
1758 | /* | |
25985edc | 1759 | * We want to do more targeted reclaim. |
4e416953 BS |
1760 | * excess >> 2 is not to excessive so as to |
1761 | * reclaim too much, nor too less that we keep | |
1762 | * coming back to reclaim from this cgroup | |
1763 | */ | |
1764 | if (total >= (excess >> 2) || | |
1765 | (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) { | |
1766 | css_put(&victim->css); | |
1767 | break; | |
1768 | } | |
1769 | } | |
1770 | } | |
4d0c066d | 1771 | if (!mem_cgroup_reclaimable(victim, noswap)) { |
04046e1a KH |
1772 | /* this cgroup's local usage == 0 */ |
1773 | css_put(&victim->css); | |
6d61ef40 BS |
1774 | continue; |
1775 | } | |
04046e1a | 1776 | /* we use swappiness of local cgroup */ |
0ae5e89c | 1777 | if (check_soft) { |
4e416953 | 1778 | ret = mem_cgroup_shrink_node_zone(victim, gfp_mask, |
0ae5e89c YH |
1779 | noswap, get_swappiness(victim), zone, |
1780 | &nr_scanned); | |
1781 | *total_scanned += nr_scanned; | |
1782 | } else | |
4e416953 BS |
1783 | ret = try_to_free_mem_cgroup_pages(victim, gfp_mask, |
1784 | noswap, get_swappiness(victim)); | |
04046e1a | 1785 | css_put(&victim->css); |
81d39c20 KH |
1786 | /* |
1787 | * At shrinking usage, we can't check we should stop here or | |
1788 | * reclaim more. It's depends on callers. last_scanned_child | |
1789 | * will work enough for keeping fairness under tree. | |
1790 | */ | |
1791 | if (shrink) | |
1792 | return ret; | |
04046e1a | 1793 | total += ret; |
4e416953 | 1794 | if (check_soft) { |
9d11ea9f | 1795 | if (!res_counter_soft_limit_excess(&root_mem->res)) |
4e416953 | 1796 | return total; |
9d11ea9f | 1797 | } else if (mem_cgroup_margin(root_mem)) |
4fd14ebf | 1798 | return total; |
6d61ef40 | 1799 | } |
04046e1a | 1800 | return total; |
6d61ef40 BS |
1801 | } |
1802 | ||
867578cb KH |
1803 | /* |
1804 | * Check OOM-Killer is already running under our hierarchy. | |
1805 | * If someone is running, return false. | |
1806 | */ | |
1807 | static bool mem_cgroup_oom_lock(struct mem_cgroup *mem) | |
1808 | { | |
7d74b06f KH |
1809 | int x, lock_count = 0; |
1810 | struct mem_cgroup *iter; | |
a636b327 | 1811 | |
7d74b06f KH |
1812 | for_each_mem_cgroup_tree(iter, mem) { |
1813 | x = atomic_inc_return(&iter->oom_lock); | |
1814 | lock_count = max(x, lock_count); | |
1815 | } | |
867578cb KH |
1816 | |
1817 | if (lock_count == 1) | |
1818 | return true; | |
1819 | return false; | |
a636b327 | 1820 | } |
0b7f569e | 1821 | |
7d74b06f | 1822 | static int mem_cgroup_oom_unlock(struct mem_cgroup *mem) |
0b7f569e | 1823 | { |
7d74b06f KH |
1824 | struct mem_cgroup *iter; |
1825 | ||
867578cb KH |
1826 | /* |
1827 | * When a new child is created while the hierarchy is under oom, | |
1828 | * mem_cgroup_oom_lock() may not be called. We have to use | |
1829 | * atomic_add_unless() here. | |
1830 | */ | |
7d74b06f KH |
1831 | for_each_mem_cgroup_tree(iter, mem) |
1832 | atomic_add_unless(&iter->oom_lock, -1, 0); | |
0b7f569e KH |
1833 | return 0; |
1834 | } | |
1835 | ||
867578cb KH |
1836 | |
1837 | static DEFINE_MUTEX(memcg_oom_mutex); | |
1838 | static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); | |
1839 | ||
dc98df5a KH |
1840 | struct oom_wait_info { |
1841 | struct mem_cgroup *mem; | |
1842 | wait_queue_t wait; | |
1843 | }; | |
1844 | ||
1845 | static int memcg_oom_wake_function(wait_queue_t *wait, | |
1846 | unsigned mode, int sync, void *arg) | |
1847 | { | |
1848 | struct mem_cgroup *wake_mem = (struct mem_cgroup *)arg; | |
1849 | struct oom_wait_info *oom_wait_info; | |
1850 | ||
1851 | oom_wait_info = container_of(wait, struct oom_wait_info, wait); | |
1852 | ||
1853 | if (oom_wait_info->mem == wake_mem) | |
1854 | goto wakeup; | |
1855 | /* if no hierarchy, no match */ | |
1856 | if (!oom_wait_info->mem->use_hierarchy || !wake_mem->use_hierarchy) | |
1857 | return 0; | |
1858 | /* | |
1859 | * Both of oom_wait_info->mem and wake_mem are stable under us. | |
1860 | * Then we can use css_is_ancestor without taking care of RCU. | |
1861 | */ | |
1862 | if (!css_is_ancestor(&oom_wait_info->mem->css, &wake_mem->css) && | |
1863 | !css_is_ancestor(&wake_mem->css, &oom_wait_info->mem->css)) | |
1864 | return 0; | |
1865 | ||
1866 | wakeup: | |
1867 | return autoremove_wake_function(wait, mode, sync, arg); | |
1868 | } | |
1869 | ||
1870 | static void memcg_wakeup_oom(struct mem_cgroup *mem) | |
1871 | { | |
1872 | /* for filtering, pass "mem" as argument. */ | |
1873 | __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, mem); | |
1874 | } | |
1875 | ||
3c11ecf4 KH |
1876 | static void memcg_oom_recover(struct mem_cgroup *mem) |
1877 | { | |
2bd9bb20 | 1878 | if (mem && atomic_read(&mem->oom_lock)) |
3c11ecf4 KH |
1879 | memcg_wakeup_oom(mem); |
1880 | } | |
1881 | ||
867578cb KH |
1882 | /* |
1883 | * try to call OOM killer. returns false if we should exit memory-reclaim loop. | |
1884 | */ | |
1885 | bool mem_cgroup_handle_oom(struct mem_cgroup *mem, gfp_t mask) | |
0b7f569e | 1886 | { |
dc98df5a | 1887 | struct oom_wait_info owait; |
3c11ecf4 | 1888 | bool locked, need_to_kill; |
867578cb | 1889 | |
dc98df5a KH |
1890 | owait.mem = mem; |
1891 | owait.wait.flags = 0; | |
1892 | owait.wait.func = memcg_oom_wake_function; | |
1893 | owait.wait.private = current; | |
1894 | INIT_LIST_HEAD(&owait.wait.task_list); | |
3c11ecf4 | 1895 | need_to_kill = true; |
867578cb KH |
1896 | /* At first, try to OOM lock hierarchy under mem.*/ |
1897 | mutex_lock(&memcg_oom_mutex); | |
1898 | locked = mem_cgroup_oom_lock(mem); | |
1899 | /* | |
1900 | * Even if signal_pending(), we can't quit charge() loop without | |
1901 | * accounting. So, UNINTERRUPTIBLE is appropriate. But SIGKILL | |
1902 | * under OOM is always welcomed, use TASK_KILLABLE here. | |
1903 | */ | |
3c11ecf4 KH |
1904 | prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); |
1905 | if (!locked || mem->oom_kill_disable) | |
1906 | need_to_kill = false; | |
1907 | if (locked) | |
9490ff27 | 1908 | mem_cgroup_oom_notify(mem); |
867578cb KH |
1909 | mutex_unlock(&memcg_oom_mutex); |
1910 | ||
3c11ecf4 KH |
1911 | if (need_to_kill) { |
1912 | finish_wait(&memcg_oom_waitq, &owait.wait); | |
867578cb | 1913 | mem_cgroup_out_of_memory(mem, mask); |
3c11ecf4 | 1914 | } else { |
867578cb | 1915 | schedule(); |
dc98df5a | 1916 | finish_wait(&memcg_oom_waitq, &owait.wait); |
867578cb KH |
1917 | } |
1918 | mutex_lock(&memcg_oom_mutex); | |
1919 | mem_cgroup_oom_unlock(mem); | |
dc98df5a | 1920 | memcg_wakeup_oom(mem); |
867578cb KH |
1921 | mutex_unlock(&memcg_oom_mutex); |
1922 | ||
1923 | if (test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current)) | |
1924 | return false; | |
1925 | /* Give chance to dying process */ | |
1926 | schedule_timeout(1); | |
1927 | return true; | |
0b7f569e KH |
1928 | } |
1929 | ||
d69b042f BS |
1930 | /* |
1931 | * Currently used to update mapped file statistics, but the routine can be | |
1932 | * generalized to update other statistics as well. | |
32047e2a KH |
1933 | * |
1934 | * Notes: Race condition | |
1935 | * | |
1936 | * We usually use page_cgroup_lock() for accessing page_cgroup member but | |
1937 | * it tends to be costly. But considering some conditions, we doesn't need | |
1938 | * to do so _always_. | |
1939 | * | |
1940 | * Considering "charge", lock_page_cgroup() is not required because all | |
1941 | * file-stat operations happen after a page is attached to radix-tree. There | |
1942 | * are no race with "charge". | |
1943 | * | |
1944 | * Considering "uncharge", we know that memcg doesn't clear pc->mem_cgroup | |
1945 | * at "uncharge" intentionally. So, we always see valid pc->mem_cgroup even | |
1946 | * if there are race with "uncharge". Statistics itself is properly handled | |
1947 | * by flags. | |
1948 | * | |
1949 | * Considering "move", this is an only case we see a race. To make the race | |
1950 | * small, we check MEM_CGROUP_ON_MOVE percpu value and detect there are | |
1951 | * possibility of race condition. If there is, we take a lock. | |
d69b042f | 1952 | */ |
26174efd | 1953 | |
2a7106f2 GT |
1954 | void mem_cgroup_update_page_stat(struct page *page, |
1955 | enum mem_cgroup_page_stat_item idx, int val) | |
d69b042f BS |
1956 | { |
1957 | struct mem_cgroup *mem; | |
32047e2a KH |
1958 | struct page_cgroup *pc = lookup_page_cgroup(page); |
1959 | bool need_unlock = false; | |
dbd4ea78 | 1960 | unsigned long uninitialized_var(flags); |
d69b042f | 1961 | |
d69b042f BS |
1962 | if (unlikely(!pc)) |
1963 | return; | |
1964 | ||
32047e2a | 1965 | rcu_read_lock(); |
d69b042f | 1966 | mem = pc->mem_cgroup; |
32047e2a KH |
1967 | if (unlikely(!mem || !PageCgroupUsed(pc))) |
1968 | goto out; | |
1969 | /* pc->mem_cgroup is unstable ? */ | |
ca3e0214 | 1970 | if (unlikely(mem_cgroup_stealed(mem)) || PageTransHuge(page)) { |
32047e2a | 1971 | /* take a lock against to access pc->mem_cgroup */ |
dbd4ea78 | 1972 | move_lock_page_cgroup(pc, &flags); |
32047e2a KH |
1973 | need_unlock = true; |
1974 | mem = pc->mem_cgroup; | |
1975 | if (!mem || !PageCgroupUsed(pc)) | |
1976 | goto out; | |
1977 | } | |
26174efd | 1978 | |
26174efd | 1979 | switch (idx) { |
2a7106f2 | 1980 | case MEMCG_NR_FILE_MAPPED: |
26174efd KH |
1981 | if (val > 0) |
1982 | SetPageCgroupFileMapped(pc); | |
1983 | else if (!page_mapped(page)) | |
0c270f8f | 1984 | ClearPageCgroupFileMapped(pc); |
2a7106f2 | 1985 | idx = MEM_CGROUP_STAT_FILE_MAPPED; |
26174efd KH |
1986 | break; |
1987 | default: | |
1988 | BUG(); | |
8725d541 | 1989 | } |
d69b042f | 1990 | |
2a7106f2 GT |
1991 | this_cpu_add(mem->stat->count[idx], val); |
1992 | ||
32047e2a KH |
1993 | out: |
1994 | if (unlikely(need_unlock)) | |
dbd4ea78 | 1995 | move_unlock_page_cgroup(pc, &flags); |
32047e2a KH |
1996 | rcu_read_unlock(); |
1997 | return; | |
d69b042f | 1998 | } |
2a7106f2 | 1999 | EXPORT_SYMBOL(mem_cgroup_update_page_stat); |
26174efd | 2000 | |
cdec2e42 KH |
2001 | /* |
2002 | * size of first charge trial. "32" comes from vmscan.c's magic value. | |
2003 | * TODO: maybe necessary to use big numbers in big irons. | |
2004 | */ | |
7ec99d62 | 2005 | #define CHARGE_BATCH 32U |
cdec2e42 KH |
2006 | struct memcg_stock_pcp { |
2007 | struct mem_cgroup *cached; /* this never be root cgroup */ | |
11c9ea4e | 2008 | unsigned int nr_pages; |
cdec2e42 | 2009 | struct work_struct work; |
26fe6168 KH |
2010 | unsigned long flags; |
2011 | #define FLUSHING_CACHED_CHARGE (0) | |
cdec2e42 KH |
2012 | }; |
2013 | static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); | |
26fe6168 | 2014 | static DEFINE_MUTEX(percpu_charge_mutex); |
cdec2e42 KH |
2015 | |
2016 | /* | |
11c9ea4e | 2017 | * Try to consume stocked charge on this cpu. If success, one page is consumed |
cdec2e42 KH |
2018 | * from local stock and true is returned. If the stock is 0 or charges from a |
2019 | * cgroup which is not current target, returns false. This stock will be | |
2020 | * refilled. | |
2021 | */ | |
2022 | static bool consume_stock(struct mem_cgroup *mem) | |
2023 | { | |
2024 | struct memcg_stock_pcp *stock; | |
2025 | bool ret = true; | |
2026 | ||
2027 | stock = &get_cpu_var(memcg_stock); | |
11c9ea4e JW |
2028 | if (mem == stock->cached && stock->nr_pages) |
2029 | stock->nr_pages--; | |
cdec2e42 KH |
2030 | else /* need to call res_counter_charge */ |
2031 | ret = false; | |
2032 | put_cpu_var(memcg_stock); | |
2033 | return ret; | |
2034 | } | |
2035 | ||
2036 | /* | |
2037 | * Returns stocks cached in percpu to res_counter and reset cached information. | |
2038 | */ | |
2039 | static void drain_stock(struct memcg_stock_pcp *stock) | |
2040 | { | |
2041 | struct mem_cgroup *old = stock->cached; | |
2042 | ||
11c9ea4e JW |
2043 | if (stock->nr_pages) { |
2044 | unsigned long bytes = stock->nr_pages * PAGE_SIZE; | |
2045 | ||
2046 | res_counter_uncharge(&old->res, bytes); | |
cdec2e42 | 2047 | if (do_swap_account) |
11c9ea4e JW |
2048 | res_counter_uncharge(&old->memsw, bytes); |
2049 | stock->nr_pages = 0; | |
cdec2e42 KH |
2050 | } |
2051 | stock->cached = NULL; | |
cdec2e42 KH |
2052 | } |
2053 | ||
2054 | /* | |
2055 | * This must be called under preempt disabled or must be called by | |
2056 | * a thread which is pinned to local cpu. | |
2057 | */ | |
2058 | static void drain_local_stock(struct work_struct *dummy) | |
2059 | { | |
2060 | struct memcg_stock_pcp *stock = &__get_cpu_var(memcg_stock); | |
2061 | drain_stock(stock); | |
26fe6168 | 2062 | clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); |
cdec2e42 KH |
2063 | } |
2064 | ||
2065 | /* | |
2066 | * Cache charges(val) which is from res_counter, to local per_cpu area. | |
320cc51d | 2067 | * This will be consumed by consume_stock() function, later. |
cdec2e42 | 2068 | */ |
11c9ea4e | 2069 | static void refill_stock(struct mem_cgroup *mem, unsigned int nr_pages) |
cdec2e42 KH |
2070 | { |
2071 | struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock); | |
2072 | ||
2073 | if (stock->cached != mem) { /* reset if necessary */ | |
2074 | drain_stock(stock); | |
2075 | stock->cached = mem; | |
2076 | } | |
11c9ea4e | 2077 | stock->nr_pages += nr_pages; |
cdec2e42 KH |
2078 | put_cpu_var(memcg_stock); |
2079 | } | |
2080 | ||
2081 | /* | |
2082 | * Tries to drain stocked charges in other cpus. This function is asynchronous | |
2083 | * and just put a work per cpu for draining localy on each cpu. Caller can | |
2084 | * expects some charges will be back to res_counter later but cannot wait for | |
2085 | * it. | |
2086 | */ | |
26fe6168 | 2087 | static void drain_all_stock_async(struct mem_cgroup *root_mem) |
cdec2e42 | 2088 | { |
26fe6168 KH |
2089 | int cpu, curcpu; |
2090 | /* | |
2091 | * If someone calls draining, avoid adding more kworker runs. | |
cdec2e42 | 2092 | */ |
26fe6168 | 2093 | if (!mutex_trylock(&percpu_charge_mutex)) |
cdec2e42 KH |
2094 | return; |
2095 | /* Notify other cpus that system-wide "drain" is running */ | |
cdec2e42 | 2096 | get_online_cpus(); |
26fe6168 KH |
2097 | /* |
2098 | * Get a hint for avoiding draining charges on the current cpu, | |
2099 | * which must be exhausted by our charging. It is not required that | |
2100 | * this be a precise check, so we use raw_smp_processor_id() instead of | |
2101 | * getcpu()/putcpu(). | |
2102 | */ | |
2103 | curcpu = raw_smp_processor_id(); | |
cdec2e42 KH |
2104 | for_each_online_cpu(cpu) { |
2105 | struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); | |
26fe6168 KH |
2106 | struct mem_cgroup *mem; |
2107 | ||
2108 | if (cpu == curcpu) | |
2109 | continue; | |
2110 | ||
2111 | mem = stock->cached; | |
2112 | if (!mem) | |
2113 | continue; | |
2114 | if (mem != root_mem) { | |
2115 | if (!root_mem->use_hierarchy) | |
2116 | continue; | |
2117 | /* check whether "mem" is under tree of "root_mem" */ | |
2118 | if (!css_is_ancestor(&mem->css, &root_mem->css)) | |
2119 | continue; | |
2120 | } | |
2121 | if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) | |
2122 | schedule_work_on(cpu, &stock->work); | |
cdec2e42 KH |
2123 | } |
2124 | put_online_cpus(); | |
26fe6168 | 2125 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2126 | /* We don't wait for flush_work */ |
2127 | } | |
2128 | ||
2129 | /* This is a synchronous drain interface. */ | |
2130 | static void drain_all_stock_sync(void) | |
2131 | { | |
2132 | /* called when force_empty is called */ | |
26fe6168 | 2133 | mutex_lock(&percpu_charge_mutex); |
cdec2e42 | 2134 | schedule_on_each_cpu(drain_local_stock); |
26fe6168 | 2135 | mutex_unlock(&percpu_charge_mutex); |
cdec2e42 KH |
2136 | } |
2137 | ||
711d3d2c KH |
2138 | /* |
2139 | * This function drains percpu counter value from DEAD cpu and | |
2140 | * move it to local cpu. Note that this function can be preempted. | |
2141 | */ | |
2142 | static void mem_cgroup_drain_pcp_counter(struct mem_cgroup *mem, int cpu) | |
2143 | { | |
2144 | int i; | |
2145 | ||
2146 | spin_lock(&mem->pcp_counter_lock); | |
2147 | for (i = 0; i < MEM_CGROUP_STAT_DATA; i++) { | |
7a159cc9 | 2148 | long x = per_cpu(mem->stat->count[i], cpu); |
711d3d2c KH |
2149 | |
2150 | per_cpu(mem->stat->count[i], cpu) = 0; | |
2151 | mem->nocpu_base.count[i] += x; | |
2152 | } | |
e9f8974f JW |
2153 | for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) { |
2154 | unsigned long x = per_cpu(mem->stat->events[i], cpu); | |
2155 | ||
2156 | per_cpu(mem->stat->events[i], cpu) = 0; | |
2157 | mem->nocpu_base.events[i] += x; | |
2158 | } | |
1489ebad KH |
2159 | /* need to clear ON_MOVE value, works as a kind of lock. */ |
2160 | per_cpu(mem->stat->count[MEM_CGROUP_ON_MOVE], cpu) = 0; | |
2161 | spin_unlock(&mem->pcp_counter_lock); | |
2162 | } | |
2163 | ||
2164 | static void synchronize_mem_cgroup_on_move(struct mem_cgroup *mem, int cpu) | |
2165 | { | |
2166 | int idx = MEM_CGROUP_ON_MOVE; | |
2167 | ||
2168 | spin_lock(&mem->pcp_counter_lock); | |
2169 | per_cpu(mem->stat->count[idx], cpu) = mem->nocpu_base.count[idx]; | |
711d3d2c KH |
2170 | spin_unlock(&mem->pcp_counter_lock); |
2171 | } | |
2172 | ||
2173 | static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, | |
cdec2e42 KH |
2174 | unsigned long action, |
2175 | void *hcpu) | |
2176 | { | |
2177 | int cpu = (unsigned long)hcpu; | |
2178 | struct memcg_stock_pcp *stock; | |
711d3d2c | 2179 | struct mem_cgroup *iter; |
cdec2e42 | 2180 | |
1489ebad KH |
2181 | if ((action == CPU_ONLINE)) { |
2182 | for_each_mem_cgroup_all(iter) | |
2183 | synchronize_mem_cgroup_on_move(iter, cpu); | |
2184 | return NOTIFY_OK; | |
2185 | } | |
2186 | ||
711d3d2c | 2187 | if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN) |
cdec2e42 | 2188 | return NOTIFY_OK; |
711d3d2c KH |
2189 | |
2190 | for_each_mem_cgroup_all(iter) | |
2191 | mem_cgroup_drain_pcp_counter(iter, cpu); | |
2192 | ||
cdec2e42 KH |
2193 | stock = &per_cpu(memcg_stock, cpu); |
2194 | drain_stock(stock); | |
2195 | return NOTIFY_OK; | |
2196 | } | |
2197 | ||
4b534334 KH |
2198 | |
2199 | /* See __mem_cgroup_try_charge() for details */ | |
2200 | enum { | |
2201 | CHARGE_OK, /* success */ | |
2202 | CHARGE_RETRY, /* need to retry but retry is not bad */ | |
2203 | CHARGE_NOMEM, /* we can't do more. return -ENOMEM */ | |
2204 | CHARGE_WOULDBLOCK, /* GFP_WAIT wasn't set and no enough res. */ | |
2205 | CHARGE_OOM_DIE, /* the current is killed because of OOM */ | |
2206 | }; | |
2207 | ||
7ec99d62 JW |
2208 | static int mem_cgroup_do_charge(struct mem_cgroup *mem, gfp_t gfp_mask, |
2209 | unsigned int nr_pages, bool oom_check) | |
4b534334 | 2210 | { |
7ec99d62 | 2211 | unsigned long csize = nr_pages * PAGE_SIZE; |
4b534334 KH |
2212 | struct mem_cgroup *mem_over_limit; |
2213 | struct res_counter *fail_res; | |
2214 | unsigned long flags = 0; | |
2215 | int ret; | |
2216 | ||
2217 | ret = res_counter_charge(&mem->res, csize, &fail_res); | |
2218 | ||
2219 | if (likely(!ret)) { | |
2220 | if (!do_swap_account) | |
2221 | return CHARGE_OK; | |
2222 | ret = res_counter_charge(&mem->memsw, csize, &fail_res); | |
2223 | if (likely(!ret)) | |
2224 | return CHARGE_OK; | |
2225 | ||
01c88e2d | 2226 | res_counter_uncharge(&mem->res, csize); |
4b534334 KH |
2227 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw); |
2228 | flags |= MEM_CGROUP_RECLAIM_NOSWAP; | |
2229 | } else | |
2230 | mem_over_limit = mem_cgroup_from_res_counter(fail_res, res); | |
9221edb7 | 2231 | /* |
7ec99d62 JW |
2232 | * nr_pages can be either a huge page (HPAGE_PMD_NR), a batch |
2233 | * of regular pages (CHARGE_BATCH), or a single regular page (1). | |
9221edb7 JW |
2234 | * |
2235 | * Never reclaim on behalf of optional batching, retry with a | |
2236 | * single page instead. | |
2237 | */ | |
7ec99d62 | 2238 | if (nr_pages == CHARGE_BATCH) |
4b534334 KH |
2239 | return CHARGE_RETRY; |
2240 | ||
2241 | if (!(gfp_mask & __GFP_WAIT)) | |
2242 | return CHARGE_WOULDBLOCK; | |
2243 | ||
2244 | ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, NULL, | |
0ae5e89c | 2245 | gfp_mask, flags, NULL); |
7ec99d62 | 2246 | if (mem_cgroup_margin(mem_over_limit) >= nr_pages) |
19942822 | 2247 | return CHARGE_RETRY; |
4b534334 | 2248 | /* |
19942822 JW |
2249 | * Even though the limit is exceeded at this point, reclaim |
2250 | * may have been able to free some pages. Retry the charge | |
2251 | * before killing the task. | |
2252 | * | |
2253 | * Only for regular pages, though: huge pages are rather | |
2254 | * unlikely to succeed so close to the limit, and we fall back | |
2255 | * to regular pages anyway in case of failure. | |
4b534334 | 2256 | */ |
7ec99d62 | 2257 | if (nr_pages == 1 && ret) |
4b534334 KH |
2258 | return CHARGE_RETRY; |
2259 | ||
2260 | /* | |
2261 | * At task move, charge accounts can be doubly counted. So, it's | |
2262 | * better to wait until the end of task_move if something is going on. | |
2263 | */ | |
2264 | if (mem_cgroup_wait_acct_move(mem_over_limit)) | |
2265 | return CHARGE_RETRY; | |
2266 | ||
2267 | /* If we don't need to call oom-killer at el, return immediately */ | |
2268 | if (!oom_check) | |
2269 | return CHARGE_NOMEM; | |
2270 | /* check OOM */ | |
2271 | if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask)) | |
2272 | return CHARGE_OOM_DIE; | |
2273 | ||
2274 | return CHARGE_RETRY; | |
2275 | } | |
2276 | ||
f817ed48 KH |
2277 | /* |
2278 | * Unlike exported interface, "oom" parameter is added. if oom==true, | |
2279 | * oom-killer can be invoked. | |
8a9f3ccd | 2280 | */ |
f817ed48 | 2281 | static int __mem_cgroup_try_charge(struct mm_struct *mm, |
ec168510 | 2282 | gfp_t gfp_mask, |
7ec99d62 JW |
2283 | unsigned int nr_pages, |
2284 | struct mem_cgroup **memcg, | |
2285 | bool oom) | |
8a9f3ccd | 2286 | { |
7ec99d62 | 2287 | unsigned int batch = max(CHARGE_BATCH, nr_pages); |
4b534334 KH |
2288 | int nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; |
2289 | struct mem_cgroup *mem = NULL; | |
2290 | int ret; | |
a636b327 | 2291 | |
867578cb KH |
2292 | /* |
2293 | * Unlike gloval-vm's OOM-kill, we're not in memory shortage | |
2294 | * in system level. So, allow to go ahead dying process in addition to | |
2295 | * MEMDIE process. | |
2296 | */ | |
2297 | if (unlikely(test_thread_flag(TIF_MEMDIE) | |
2298 | || fatal_signal_pending(current))) | |
2299 | goto bypass; | |
a636b327 | 2300 | |
8a9f3ccd | 2301 | /* |
3be91277 HD |
2302 | * We always charge the cgroup the mm_struct belongs to. |
2303 | * The mm_struct's mem_cgroup changes on task migration if the | |
8a9f3ccd BS |
2304 | * thread group leader migrates. It's possible that mm is not |
2305 | * set, if so charge the init_mm (happens for pagecache usage). | |
2306 | */ | |
f75ca962 KH |
2307 | if (!*memcg && !mm) |
2308 | goto bypass; | |
2309 | again: | |
2310 | if (*memcg) { /* css should be a valid one */ | |
4b534334 | 2311 | mem = *memcg; |
f75ca962 KH |
2312 | VM_BUG_ON(css_is_removed(&mem->css)); |
2313 | if (mem_cgroup_is_root(mem)) | |
2314 | goto done; | |
7ec99d62 | 2315 | if (nr_pages == 1 && consume_stock(mem)) |
f75ca962 | 2316 | goto done; |
4b534334 KH |
2317 | css_get(&mem->css); |
2318 | } else { | |
f75ca962 | 2319 | struct task_struct *p; |
54595fe2 | 2320 | |
f75ca962 KH |
2321 | rcu_read_lock(); |
2322 | p = rcu_dereference(mm->owner); | |
f75ca962 | 2323 | /* |
ebb76ce1 KH |
2324 | * Because we don't have task_lock(), "p" can exit. |
2325 | * In that case, "mem" can point to root or p can be NULL with | |
2326 | * race with swapoff. Then, we have small risk of mis-accouning. | |
2327 | * But such kind of mis-account by race always happens because | |
2328 | * we don't have cgroup_mutex(). It's overkill and we allo that | |
2329 | * small race, here. | |
2330 | * (*) swapoff at el will charge against mm-struct not against | |
2331 | * task-struct. So, mm->owner can be NULL. | |
f75ca962 KH |
2332 | */ |
2333 | mem = mem_cgroup_from_task(p); | |
ebb76ce1 | 2334 | if (!mem || mem_cgroup_is_root(mem)) { |
f75ca962 KH |
2335 | rcu_read_unlock(); |
2336 | goto done; | |
2337 | } | |
7ec99d62 | 2338 | if (nr_pages == 1 && consume_stock(mem)) { |
f75ca962 KH |
2339 | /* |
2340 | * It seems dagerous to access memcg without css_get(). | |
2341 | * But considering how consume_stok works, it's not | |
2342 | * necessary. If consume_stock success, some charges | |
2343 | * from this memcg are cached on this cpu. So, we | |
2344 | * don't need to call css_get()/css_tryget() before | |
2345 | * calling consume_stock(). | |
2346 | */ | |
2347 | rcu_read_unlock(); | |
2348 | goto done; | |
2349 | } | |
2350 | /* after here, we may be blocked. we need to get refcnt */ | |
2351 | if (!css_tryget(&mem->css)) { | |
2352 | rcu_read_unlock(); | |
2353 | goto again; | |
2354 | } | |
2355 | rcu_read_unlock(); | |
2356 | } | |
8a9f3ccd | 2357 | |
4b534334 KH |
2358 | do { |
2359 | bool oom_check; | |
7a81b88c | 2360 | |
4b534334 | 2361 | /* If killed, bypass charge */ |
f75ca962 KH |
2362 | if (fatal_signal_pending(current)) { |
2363 | css_put(&mem->css); | |
4b534334 | 2364 | goto bypass; |
f75ca962 | 2365 | } |
6d61ef40 | 2366 | |
4b534334 KH |
2367 | oom_check = false; |
2368 | if (oom && !nr_oom_retries) { | |
2369 | oom_check = true; | |
2370 | nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
cdec2e42 | 2371 | } |
66e1707b | 2372 | |
7ec99d62 | 2373 | ret = mem_cgroup_do_charge(mem, gfp_mask, batch, oom_check); |
4b534334 KH |
2374 | switch (ret) { |
2375 | case CHARGE_OK: | |
2376 | break; | |
2377 | case CHARGE_RETRY: /* not in OOM situation but retry */ | |
7ec99d62 | 2378 | batch = nr_pages; |
f75ca962 KH |
2379 | css_put(&mem->css); |
2380 | mem = NULL; | |
2381 | goto again; | |
4b534334 | 2382 | case CHARGE_WOULDBLOCK: /* !__GFP_WAIT */ |
f75ca962 | 2383 | css_put(&mem->css); |
4b534334 KH |
2384 | goto nomem; |
2385 | case CHARGE_NOMEM: /* OOM routine works */ | |
f75ca962 KH |
2386 | if (!oom) { |
2387 | css_put(&mem->css); | |
867578cb | 2388 | goto nomem; |
f75ca962 | 2389 | } |
4b534334 KH |
2390 | /* If oom, we never return -ENOMEM */ |
2391 | nr_oom_retries--; | |
2392 | break; | |
2393 | case CHARGE_OOM_DIE: /* Killed by OOM Killer */ | |
f75ca962 | 2394 | css_put(&mem->css); |
867578cb | 2395 | goto bypass; |
66e1707b | 2396 | } |
4b534334 KH |
2397 | } while (ret != CHARGE_OK); |
2398 | ||
7ec99d62 JW |
2399 | if (batch > nr_pages) |
2400 | refill_stock(mem, batch - nr_pages); | |
f75ca962 | 2401 | css_put(&mem->css); |
0c3e73e8 | 2402 | done: |
f75ca962 | 2403 | *memcg = mem; |
7a81b88c KH |
2404 | return 0; |
2405 | nomem: | |
f75ca962 | 2406 | *memcg = NULL; |
7a81b88c | 2407 | return -ENOMEM; |
867578cb KH |
2408 | bypass: |
2409 | *memcg = NULL; | |
2410 | return 0; | |
7a81b88c | 2411 | } |
8a9f3ccd | 2412 | |
a3032a2c DN |
2413 | /* |
2414 | * Somemtimes we have to undo a charge we got by try_charge(). | |
2415 | * This function is for that and do uncharge, put css's refcnt. | |
2416 | * gotten by try_charge(). | |
2417 | */ | |
854ffa8d | 2418 | static void __mem_cgroup_cancel_charge(struct mem_cgroup *mem, |
e7018b8d | 2419 | unsigned int nr_pages) |
a3032a2c DN |
2420 | { |
2421 | if (!mem_cgroup_is_root(mem)) { | |
e7018b8d JW |
2422 | unsigned long bytes = nr_pages * PAGE_SIZE; |
2423 | ||
2424 | res_counter_uncharge(&mem->res, bytes); | |
a3032a2c | 2425 | if (do_swap_account) |
e7018b8d | 2426 | res_counter_uncharge(&mem->memsw, bytes); |
a3032a2c | 2427 | } |
854ffa8d DN |
2428 | } |
2429 | ||
a3b2d692 KH |
2430 | /* |
2431 | * A helper function to get mem_cgroup from ID. must be called under | |
2432 | * rcu_read_lock(). The caller must check css_is_removed() or some if | |
2433 | * it's concern. (dropping refcnt from swap can be called against removed | |
2434 | * memcg.) | |
2435 | */ | |
2436 | static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) | |
2437 | { | |
2438 | struct cgroup_subsys_state *css; | |
2439 | ||
2440 | /* ID 0 is unused ID */ | |
2441 | if (!id) | |
2442 | return NULL; | |
2443 | css = css_lookup(&mem_cgroup_subsys, id); | |
2444 | if (!css) | |
2445 | return NULL; | |
2446 | return container_of(css, struct mem_cgroup, css); | |
2447 | } | |
2448 | ||
e42d9d5d | 2449 | struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) |
b5a84319 | 2450 | { |
e42d9d5d | 2451 | struct mem_cgroup *mem = NULL; |
3c776e64 | 2452 | struct page_cgroup *pc; |
a3b2d692 | 2453 | unsigned short id; |
b5a84319 KH |
2454 | swp_entry_t ent; |
2455 | ||
3c776e64 DN |
2456 | VM_BUG_ON(!PageLocked(page)); |
2457 | ||
3c776e64 | 2458 | pc = lookup_page_cgroup(page); |
c0bd3f63 | 2459 | lock_page_cgroup(pc); |
a3b2d692 | 2460 | if (PageCgroupUsed(pc)) { |
3c776e64 | 2461 | mem = pc->mem_cgroup; |
a3b2d692 KH |
2462 | if (mem && !css_tryget(&mem->css)) |
2463 | mem = NULL; | |
e42d9d5d | 2464 | } else if (PageSwapCache(page)) { |
3c776e64 | 2465 | ent.val = page_private(page); |
a3b2d692 KH |
2466 | id = lookup_swap_cgroup(ent); |
2467 | rcu_read_lock(); | |
2468 | mem = mem_cgroup_lookup(id); | |
2469 | if (mem && !css_tryget(&mem->css)) | |
2470 | mem = NULL; | |
2471 | rcu_read_unlock(); | |
3c776e64 | 2472 | } |
c0bd3f63 | 2473 | unlock_page_cgroup(pc); |
b5a84319 KH |
2474 | return mem; |
2475 | } | |
2476 | ||
ca3e0214 | 2477 | static void __mem_cgroup_commit_charge(struct mem_cgroup *mem, |
5564e88b | 2478 | struct page *page, |
7ec99d62 | 2479 | unsigned int nr_pages, |
ca3e0214 | 2480 | struct page_cgroup *pc, |
7ec99d62 | 2481 | enum charge_type ctype) |
7a81b88c | 2482 | { |
ca3e0214 KH |
2483 | lock_page_cgroup(pc); |
2484 | if (unlikely(PageCgroupUsed(pc))) { | |
2485 | unlock_page_cgroup(pc); | |
e7018b8d | 2486 | __mem_cgroup_cancel_charge(mem, nr_pages); |
ca3e0214 KH |
2487 | return; |
2488 | } | |
2489 | /* | |
2490 | * we don't need page_cgroup_lock about tail pages, becase they are not | |
2491 | * accessed by any other context at this point. | |
2492 | */ | |
8a9f3ccd | 2493 | pc->mem_cgroup = mem; |
261fb61a KH |
2494 | /* |
2495 | * We access a page_cgroup asynchronously without lock_page_cgroup(). | |
2496 | * Especially when a page_cgroup is taken from a page, pc->mem_cgroup | |
2497 | * is accessed after testing USED bit. To make pc->mem_cgroup visible | |
2498 | * before USED bit, we need memory barrier here. | |
2499 | * See mem_cgroup_add_lru_list(), etc. | |
2500 | */ | |
08e552c6 | 2501 | smp_wmb(); |
4b3bde4c BS |
2502 | switch (ctype) { |
2503 | case MEM_CGROUP_CHARGE_TYPE_CACHE: | |
2504 | case MEM_CGROUP_CHARGE_TYPE_SHMEM: | |
2505 | SetPageCgroupCache(pc); | |
2506 | SetPageCgroupUsed(pc); | |
2507 | break; | |
2508 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
2509 | ClearPageCgroupCache(pc); | |
2510 | SetPageCgroupUsed(pc); | |
2511 | break; | |
2512 | default: | |
2513 | break; | |
2514 | } | |
3be91277 | 2515 | |
ca3e0214 | 2516 | mem_cgroup_charge_statistics(mem, PageCgroupCache(pc), nr_pages); |
52d4b9ac | 2517 | unlock_page_cgroup(pc); |
430e4863 KH |
2518 | /* |
2519 | * "charge_statistics" updated event counter. Then, check it. | |
2520 | * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree. | |
2521 | * if they exceeds softlimit. | |
2522 | */ | |
5564e88b | 2523 | memcg_check_events(mem, page); |
7a81b88c | 2524 | } |
66e1707b | 2525 | |
ca3e0214 KH |
2526 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
2527 | ||
2528 | #define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) | (1 << PCG_MOVE_LOCK) |\ | |
2529 | (1 << PCG_ACCT_LRU) | (1 << PCG_MIGRATION)) | |
2530 | /* | |
2531 | * Because tail pages are not marked as "used", set it. We're under | |
2532 | * zone->lru_lock, 'splitting on pmd' and compund_lock. | |
2533 | */ | |
2534 | void mem_cgroup_split_huge_fixup(struct page *head, struct page *tail) | |
2535 | { | |
2536 | struct page_cgroup *head_pc = lookup_page_cgroup(head); | |
2537 | struct page_cgroup *tail_pc = lookup_page_cgroup(tail); | |
2538 | unsigned long flags; | |
2539 | ||
3d37c4a9 KH |
2540 | if (mem_cgroup_disabled()) |
2541 | return; | |
ca3e0214 | 2542 | /* |
ece35ca8 | 2543 | * We have no races with charge/uncharge but will have races with |
ca3e0214 KH |
2544 | * page state accounting. |
2545 | */ | |
2546 | move_lock_page_cgroup(head_pc, &flags); | |
2547 | ||
2548 | tail_pc->mem_cgroup = head_pc->mem_cgroup; | |
2549 | smp_wmb(); /* see __commit_charge() */ | |
ece35ca8 KH |
2550 | if (PageCgroupAcctLRU(head_pc)) { |
2551 | enum lru_list lru; | |
2552 | struct mem_cgroup_per_zone *mz; | |
2553 | ||
2554 | /* | |
2555 | * LRU flags cannot be copied because we need to add tail | |
2556 | *.page to LRU by generic call and our hook will be called. | |
2557 | * We hold lru_lock, then, reduce counter directly. | |
2558 | */ | |
2559 | lru = page_lru(head); | |
97a6c37b | 2560 | mz = page_cgroup_zoneinfo(head_pc->mem_cgroup, head); |
ece35ca8 KH |
2561 | MEM_CGROUP_ZSTAT(mz, lru) -= 1; |
2562 | } | |
ca3e0214 KH |
2563 | tail_pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT; |
2564 | move_unlock_page_cgroup(head_pc, &flags); | |
2565 | } | |
2566 | #endif | |
2567 | ||
f817ed48 | 2568 | /** |
de3638d9 | 2569 | * mem_cgroup_move_account - move account of the page |
5564e88b | 2570 | * @page: the page |
7ec99d62 | 2571 | * @nr_pages: number of regular pages (>1 for huge pages) |
f817ed48 KH |
2572 | * @pc: page_cgroup of the page. |
2573 | * @from: mem_cgroup which the page is moved from. | |
2574 | * @to: mem_cgroup which the page is moved to. @from != @to. | |
854ffa8d | 2575 | * @uncharge: whether we should call uncharge and css_put against @from. |
f817ed48 KH |
2576 | * |
2577 | * The caller must confirm following. | |
08e552c6 | 2578 | * - page is not on LRU (isolate_page() is useful.) |
7ec99d62 | 2579 | * - compound_lock is held when nr_pages > 1 |
f817ed48 | 2580 | * |
854ffa8d | 2581 | * This function doesn't do "charge" nor css_get to new cgroup. It should be |
25985edc | 2582 | * done by a caller(__mem_cgroup_try_charge would be useful). If @uncharge is |
854ffa8d DN |
2583 | * true, this function does "uncharge" from old cgroup, but it doesn't if |
2584 | * @uncharge is false, so a caller should do "uncharge". | |
f817ed48 | 2585 | */ |
7ec99d62 JW |
2586 | static int mem_cgroup_move_account(struct page *page, |
2587 | unsigned int nr_pages, | |
2588 | struct page_cgroup *pc, | |
2589 | struct mem_cgroup *from, | |
2590 | struct mem_cgroup *to, | |
2591 | bool uncharge) | |
f817ed48 | 2592 | { |
de3638d9 JW |
2593 | unsigned long flags; |
2594 | int ret; | |
987eba66 | 2595 | |
f817ed48 | 2596 | VM_BUG_ON(from == to); |
5564e88b | 2597 | VM_BUG_ON(PageLRU(page)); |
de3638d9 JW |
2598 | /* |
2599 | * The page is isolated from LRU. So, collapse function | |
2600 | * will not handle this page. But page splitting can happen. | |
2601 | * Do this check under compound_page_lock(). The caller should | |
2602 | * hold it. | |
2603 | */ | |
2604 | ret = -EBUSY; | |
7ec99d62 | 2605 | if (nr_pages > 1 && !PageTransHuge(page)) |
de3638d9 JW |
2606 | goto out; |
2607 | ||
2608 | lock_page_cgroup(pc); | |
2609 | ||
2610 | ret = -EINVAL; | |
2611 | if (!PageCgroupUsed(pc) || pc->mem_cgroup != from) | |
2612 | goto unlock; | |
2613 | ||
2614 | move_lock_page_cgroup(pc, &flags); | |
f817ed48 | 2615 | |
8725d541 | 2616 | if (PageCgroupFileMapped(pc)) { |
c62b1a3b KH |
2617 | /* Update mapped_file data for mem_cgroup */ |
2618 | preempt_disable(); | |
2619 | __this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2620 | __this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); | |
2621 | preempt_enable(); | |
d69b042f | 2622 | } |
987eba66 | 2623 | mem_cgroup_charge_statistics(from, PageCgroupCache(pc), -nr_pages); |
854ffa8d DN |
2624 | if (uncharge) |
2625 | /* This is not "cancel", but cancel_charge does all we need. */ | |
e7018b8d | 2626 | __mem_cgroup_cancel_charge(from, nr_pages); |
d69b042f | 2627 | |
854ffa8d | 2628 | /* caller should have done css_get */ |
08e552c6 | 2629 | pc->mem_cgroup = to; |
987eba66 | 2630 | mem_cgroup_charge_statistics(to, PageCgroupCache(pc), nr_pages); |
88703267 KH |
2631 | /* |
2632 | * We charges against "to" which may not have any tasks. Then, "to" | |
2633 | * can be under rmdir(). But in current implementation, caller of | |
4ffef5fe | 2634 | * this function is just force_empty() and move charge, so it's |
25985edc | 2635 | * guaranteed that "to" is never removed. So, we don't check rmdir |
4ffef5fe | 2636 | * status here. |
88703267 | 2637 | */ |
de3638d9 JW |
2638 | move_unlock_page_cgroup(pc, &flags); |
2639 | ret = 0; | |
2640 | unlock: | |
57f9fd7d | 2641 | unlock_page_cgroup(pc); |
d2265e6f KH |
2642 | /* |
2643 | * check events | |
2644 | */ | |
5564e88b JW |
2645 | memcg_check_events(to, page); |
2646 | memcg_check_events(from, page); | |
de3638d9 | 2647 | out: |
f817ed48 KH |
2648 | return ret; |
2649 | } | |
2650 | ||
2651 | /* | |
2652 | * move charges to its parent. | |
2653 | */ | |
2654 | ||
5564e88b JW |
2655 | static int mem_cgroup_move_parent(struct page *page, |
2656 | struct page_cgroup *pc, | |
f817ed48 KH |
2657 | struct mem_cgroup *child, |
2658 | gfp_t gfp_mask) | |
2659 | { | |
2660 | struct cgroup *cg = child->css.cgroup; | |
2661 | struct cgroup *pcg = cg->parent; | |
2662 | struct mem_cgroup *parent; | |
7ec99d62 | 2663 | unsigned int nr_pages; |
4be4489f | 2664 | unsigned long uninitialized_var(flags); |
f817ed48 KH |
2665 | int ret; |
2666 | ||
2667 | /* Is ROOT ? */ | |
2668 | if (!pcg) | |
2669 | return -EINVAL; | |
2670 | ||
57f9fd7d DN |
2671 | ret = -EBUSY; |
2672 | if (!get_page_unless_zero(page)) | |
2673 | goto out; | |
2674 | if (isolate_lru_page(page)) | |
2675 | goto put; | |
52dbb905 | 2676 | |
7ec99d62 | 2677 | nr_pages = hpage_nr_pages(page); |
08e552c6 | 2678 | |
f817ed48 | 2679 | parent = mem_cgroup_from_cont(pcg); |
7ec99d62 | 2680 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, nr_pages, &parent, false); |
a636b327 | 2681 | if (ret || !parent) |
57f9fd7d | 2682 | goto put_back; |
f817ed48 | 2683 | |
7ec99d62 | 2684 | if (nr_pages > 1) |
987eba66 KH |
2685 | flags = compound_lock_irqsave(page); |
2686 | ||
7ec99d62 | 2687 | ret = mem_cgroup_move_account(page, nr_pages, pc, child, parent, true); |
854ffa8d | 2688 | if (ret) |
7ec99d62 | 2689 | __mem_cgroup_cancel_charge(parent, nr_pages); |
8dba474f | 2690 | |
7ec99d62 | 2691 | if (nr_pages > 1) |
987eba66 | 2692 | compound_unlock_irqrestore(page, flags); |
8dba474f | 2693 | put_back: |
08e552c6 | 2694 | putback_lru_page(page); |
57f9fd7d | 2695 | put: |
40d58138 | 2696 | put_page(page); |
57f9fd7d | 2697 | out: |
f817ed48 KH |
2698 | return ret; |
2699 | } | |
2700 | ||
7a81b88c KH |
2701 | /* |
2702 | * Charge the memory controller for page usage. | |
2703 | * Return | |
2704 | * 0 if the charge was successful | |
2705 | * < 0 if the cgroup is over its limit | |
2706 | */ | |
2707 | static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, | |
73045c47 | 2708 | gfp_t gfp_mask, enum charge_type ctype) |
7a81b88c | 2709 | { |
73045c47 | 2710 | struct mem_cgroup *mem = NULL; |
7ec99d62 | 2711 | unsigned int nr_pages = 1; |
7a81b88c | 2712 | struct page_cgroup *pc; |
8493ae43 | 2713 | bool oom = true; |
7a81b88c | 2714 | int ret; |
ec168510 | 2715 | |
37c2ac78 | 2716 | if (PageTransHuge(page)) { |
7ec99d62 | 2717 | nr_pages <<= compound_order(page); |
37c2ac78 | 2718 | VM_BUG_ON(!PageTransHuge(page)); |
8493ae43 JW |
2719 | /* |
2720 | * Never OOM-kill a process for a huge page. The | |
2721 | * fault handler will fall back to regular pages. | |
2722 | */ | |
2723 | oom = false; | |
37c2ac78 | 2724 | } |
7a81b88c KH |
2725 | |
2726 | pc = lookup_page_cgroup(page); | |
af4a6621 | 2727 | BUG_ON(!pc); /* XXX: remove this and move pc lookup into commit */ |
7a81b88c | 2728 | |
7ec99d62 | 2729 | ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &mem, oom); |
a636b327 | 2730 | if (ret || !mem) |
7a81b88c KH |
2731 | return ret; |
2732 | ||
7ec99d62 | 2733 | __mem_cgroup_commit_charge(mem, page, nr_pages, pc, ctype); |
8a9f3ccd | 2734 | return 0; |
8a9f3ccd BS |
2735 | } |
2736 | ||
7a81b88c KH |
2737 | int mem_cgroup_newpage_charge(struct page *page, |
2738 | struct mm_struct *mm, gfp_t gfp_mask) | |
217bc319 | 2739 | { |
f8d66542 | 2740 | if (mem_cgroup_disabled()) |
cede86ac | 2741 | return 0; |
69029cd5 KH |
2742 | /* |
2743 | * If already mapped, we don't have to account. | |
2744 | * If page cache, page->mapping has address_space. | |
2745 | * But page->mapping may have out-of-use anon_vma pointer, | |
2746 | * detecit it by PageAnon() check. newly-mapped-anon's page->mapping | |
2747 | * is NULL. | |
2748 | */ | |
2749 | if (page_mapped(page) || (page->mapping && !PageAnon(page))) | |
2750 | return 0; | |
2751 | if (unlikely(!mm)) | |
2752 | mm = &init_mm; | |
217bc319 | 2753 | return mem_cgroup_charge_common(page, mm, gfp_mask, |
73045c47 | 2754 | MEM_CGROUP_CHARGE_TYPE_MAPPED); |
217bc319 KH |
2755 | } |
2756 | ||
83aae4c7 DN |
2757 | static void |
2758 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
2759 | enum charge_type ctype); | |
2760 | ||
5a6475a4 KH |
2761 | static void |
2762 | __mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *mem, | |
2763 | enum charge_type ctype) | |
2764 | { | |
2765 | struct page_cgroup *pc = lookup_page_cgroup(page); | |
2766 | /* | |
2767 | * In some case, SwapCache, FUSE(splice_buf->radixtree), the page | |
2768 | * is already on LRU. It means the page may on some other page_cgroup's | |
2769 | * LRU. Take care of it. | |
2770 | */ | |
2771 | mem_cgroup_lru_del_before_commit(page); | |
2772 | __mem_cgroup_commit_charge(mem, page, 1, pc, ctype); | |
2773 | mem_cgroup_lru_add_after_commit(page); | |
2774 | return; | |
2775 | } | |
2776 | ||
e1a1cd59 BS |
2777 | int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, |
2778 | gfp_t gfp_mask) | |
8697d331 | 2779 | { |
5a6475a4 | 2780 | struct mem_cgroup *mem = NULL; |
b5a84319 KH |
2781 | int ret; |
2782 | ||
f8d66542 | 2783 | if (mem_cgroup_disabled()) |
cede86ac | 2784 | return 0; |
52d4b9ac KH |
2785 | if (PageCompound(page)) |
2786 | return 0; | |
accf163e KH |
2787 | /* |
2788 | * Corner case handling. This is called from add_to_page_cache() | |
2789 | * in usual. But some FS (shmem) precharges this page before calling it | |
2790 | * and call add_to_page_cache() with GFP_NOWAIT. | |
2791 | * | |
2792 | * For GFP_NOWAIT case, the page may be pre-charged before calling | |
2793 | * add_to_page_cache(). (See shmem.c) check it here and avoid to call | |
2794 | * charge twice. (It works but has to pay a bit larger cost.) | |
b5a84319 KH |
2795 | * And when the page is SwapCache, it should take swap information |
2796 | * into account. This is under lock_page() now. | |
accf163e KH |
2797 | */ |
2798 | if (!(gfp_mask & __GFP_WAIT)) { | |
2799 | struct page_cgroup *pc; | |
2800 | ||
52d4b9ac KH |
2801 | pc = lookup_page_cgroup(page); |
2802 | if (!pc) | |
2803 | return 0; | |
2804 | lock_page_cgroup(pc); | |
2805 | if (PageCgroupUsed(pc)) { | |
2806 | unlock_page_cgroup(pc); | |
accf163e KH |
2807 | return 0; |
2808 | } | |
52d4b9ac | 2809 | unlock_page_cgroup(pc); |
accf163e KH |
2810 | } |
2811 | ||
73045c47 | 2812 | if (unlikely(!mm)) |
8697d331 | 2813 | mm = &init_mm; |
accf163e | 2814 | |
5a6475a4 KH |
2815 | if (page_is_file_cache(page)) { |
2816 | ret = __mem_cgroup_try_charge(mm, gfp_mask, 1, &mem, true); | |
2817 | if (ret || !mem) | |
2818 | return ret; | |
b5a84319 | 2819 | |
5a6475a4 KH |
2820 | /* |
2821 | * FUSE reuses pages without going through the final | |
2822 | * put that would remove them from the LRU list, make | |
2823 | * sure that they get relinked properly. | |
2824 | */ | |
2825 | __mem_cgroup_commit_charge_lrucare(page, mem, | |
2826 | MEM_CGROUP_CHARGE_TYPE_CACHE); | |
2827 | return ret; | |
2828 | } | |
83aae4c7 DN |
2829 | /* shmem */ |
2830 | if (PageSwapCache(page)) { | |
2831 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); | |
2832 | if (!ret) | |
2833 | __mem_cgroup_commit_charge_swapin(page, mem, | |
2834 | MEM_CGROUP_CHARGE_TYPE_SHMEM); | |
2835 | } else | |
2836 | ret = mem_cgroup_charge_common(page, mm, gfp_mask, | |
73045c47 | 2837 | MEM_CGROUP_CHARGE_TYPE_SHMEM); |
b5a84319 | 2838 | |
b5a84319 | 2839 | return ret; |
e8589cc1 KH |
2840 | } |
2841 | ||
54595fe2 KH |
2842 | /* |
2843 | * While swap-in, try_charge -> commit or cancel, the page is locked. | |
2844 | * And when try_charge() successfully returns, one refcnt to memcg without | |
21ae2956 | 2845 | * struct page_cgroup is acquired. This refcnt will be consumed by |
54595fe2 KH |
2846 | * "commit()" or removed by "cancel()" |
2847 | */ | |
8c7c6e34 KH |
2848 | int mem_cgroup_try_charge_swapin(struct mm_struct *mm, |
2849 | struct page *page, | |
2850 | gfp_t mask, struct mem_cgroup **ptr) | |
2851 | { | |
2852 | struct mem_cgroup *mem; | |
54595fe2 | 2853 | int ret; |
8c7c6e34 | 2854 | |
56039efa KH |
2855 | *ptr = NULL; |
2856 | ||
f8d66542 | 2857 | if (mem_cgroup_disabled()) |
8c7c6e34 KH |
2858 | return 0; |
2859 | ||
2860 | if (!do_swap_account) | |
2861 | goto charge_cur_mm; | |
8c7c6e34 KH |
2862 | /* |
2863 | * A racing thread's fault, or swapoff, may have already updated | |
407f9c8b HD |
2864 | * the pte, and even removed page from swap cache: in those cases |
2865 | * do_swap_page()'s pte_same() test will fail; but there's also a | |
2866 | * KSM case which does need to charge the page. | |
8c7c6e34 KH |
2867 | */ |
2868 | if (!PageSwapCache(page)) | |
407f9c8b | 2869 | goto charge_cur_mm; |
e42d9d5d | 2870 | mem = try_get_mem_cgroup_from_page(page); |
54595fe2 KH |
2871 | if (!mem) |
2872 | goto charge_cur_mm; | |
8c7c6e34 | 2873 | *ptr = mem; |
7ec99d62 | 2874 | ret = __mem_cgroup_try_charge(NULL, mask, 1, ptr, true); |
54595fe2 KH |
2875 | css_put(&mem->css); |
2876 | return ret; | |
8c7c6e34 KH |
2877 | charge_cur_mm: |
2878 | if (unlikely(!mm)) | |
2879 | mm = &init_mm; | |
7ec99d62 | 2880 | return __mem_cgroup_try_charge(mm, mask, 1, ptr, true); |
8c7c6e34 KH |
2881 | } |
2882 | ||
83aae4c7 DN |
2883 | static void |
2884 | __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, | |
2885 | enum charge_type ctype) | |
7a81b88c | 2886 | { |
f8d66542 | 2887 | if (mem_cgroup_disabled()) |
7a81b88c KH |
2888 | return; |
2889 | if (!ptr) | |
2890 | return; | |
88703267 | 2891 | cgroup_exclude_rmdir(&ptr->css); |
5a6475a4 KH |
2892 | |
2893 | __mem_cgroup_commit_charge_lrucare(page, ptr, ctype); | |
8c7c6e34 KH |
2894 | /* |
2895 | * Now swap is on-memory. This means this page may be | |
2896 | * counted both as mem and swap....double count. | |
03f3c433 KH |
2897 | * Fix it by uncharging from memsw. Basically, this SwapCache is stable |
2898 | * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page() | |
2899 | * may call delete_from_swap_cache() before reach here. | |
8c7c6e34 | 2900 | */ |
03f3c433 | 2901 | if (do_swap_account && PageSwapCache(page)) { |
8c7c6e34 | 2902 | swp_entry_t ent = {.val = page_private(page)}; |
a3b2d692 | 2903 | unsigned short id; |
8c7c6e34 | 2904 | struct mem_cgroup *memcg; |
a3b2d692 KH |
2905 | |
2906 | id = swap_cgroup_record(ent, 0); | |
2907 | rcu_read_lock(); | |
2908 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 2909 | if (memcg) { |
a3b2d692 KH |
2910 | /* |
2911 | * This recorded memcg can be obsolete one. So, avoid | |
2912 | * calling css_tryget | |
2913 | */ | |
0c3e73e8 | 2914 | if (!mem_cgroup_is_root(memcg)) |
4e649152 | 2915 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
0c3e73e8 | 2916 | mem_cgroup_swap_statistics(memcg, false); |
8c7c6e34 KH |
2917 | mem_cgroup_put(memcg); |
2918 | } | |
a3b2d692 | 2919 | rcu_read_unlock(); |
8c7c6e34 | 2920 | } |
88703267 KH |
2921 | /* |
2922 | * At swapin, we may charge account against cgroup which has no tasks. | |
2923 | * So, rmdir()->pre_destroy() can be called while we do this charge. | |
2924 | * In that case, we need to call pre_destroy() again. check it here. | |
2925 | */ | |
2926 | cgroup_release_and_wakeup_rmdir(&ptr->css); | |
7a81b88c KH |
2927 | } |
2928 | ||
83aae4c7 DN |
2929 | void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) |
2930 | { | |
2931 | __mem_cgroup_commit_charge_swapin(page, ptr, | |
2932 | MEM_CGROUP_CHARGE_TYPE_MAPPED); | |
2933 | } | |
2934 | ||
7a81b88c KH |
2935 | void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem) |
2936 | { | |
f8d66542 | 2937 | if (mem_cgroup_disabled()) |
7a81b88c KH |
2938 | return; |
2939 | if (!mem) | |
2940 | return; | |
e7018b8d | 2941 | __mem_cgroup_cancel_charge(mem, 1); |
7a81b88c KH |
2942 | } |
2943 | ||
7ec99d62 JW |
2944 | static void mem_cgroup_do_uncharge(struct mem_cgroup *mem, |
2945 | unsigned int nr_pages, | |
2946 | const enum charge_type ctype) | |
569b846d KH |
2947 | { |
2948 | struct memcg_batch_info *batch = NULL; | |
2949 | bool uncharge_memsw = true; | |
7ec99d62 | 2950 | |
569b846d KH |
2951 | /* If swapout, usage of swap doesn't decrease */ |
2952 | if (!do_swap_account || ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) | |
2953 | uncharge_memsw = false; | |
569b846d KH |
2954 | |
2955 | batch = ¤t->memcg_batch; | |
2956 | /* | |
2957 | * In usual, we do css_get() when we remember memcg pointer. | |
2958 | * But in this case, we keep res->usage until end of a series of | |
2959 | * uncharges. Then, it's ok to ignore memcg's refcnt. | |
2960 | */ | |
2961 | if (!batch->memcg) | |
2962 | batch->memcg = mem; | |
3c11ecf4 KH |
2963 | /* |
2964 | * do_batch > 0 when unmapping pages or inode invalidate/truncate. | |
25985edc | 2965 | * In those cases, all pages freed continuously can be expected to be in |
3c11ecf4 KH |
2966 | * the same cgroup and we have chance to coalesce uncharges. |
2967 | * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE) | |
2968 | * because we want to do uncharge as soon as possible. | |
2969 | */ | |
2970 | ||
2971 | if (!batch->do_batch || test_thread_flag(TIF_MEMDIE)) | |
2972 | goto direct_uncharge; | |
2973 | ||
7ec99d62 | 2974 | if (nr_pages > 1) |
ec168510 AA |
2975 | goto direct_uncharge; |
2976 | ||
569b846d KH |
2977 | /* |
2978 | * In typical case, batch->memcg == mem. This means we can | |
2979 | * merge a series of uncharges to an uncharge of res_counter. | |
2980 | * If not, we uncharge res_counter ony by one. | |
2981 | */ | |
2982 | if (batch->memcg != mem) | |
2983 | goto direct_uncharge; | |
2984 | /* remember freed charge and uncharge it later */ | |
7ffd4ca7 | 2985 | batch->nr_pages++; |
569b846d | 2986 | if (uncharge_memsw) |
7ffd4ca7 | 2987 | batch->memsw_nr_pages++; |
569b846d KH |
2988 | return; |
2989 | direct_uncharge: | |
7ec99d62 | 2990 | res_counter_uncharge(&mem->res, nr_pages * PAGE_SIZE); |
569b846d | 2991 | if (uncharge_memsw) |
7ec99d62 | 2992 | res_counter_uncharge(&mem->memsw, nr_pages * PAGE_SIZE); |
3c11ecf4 KH |
2993 | if (unlikely(batch->memcg != mem)) |
2994 | memcg_oom_recover(mem); | |
569b846d KH |
2995 | return; |
2996 | } | |
7a81b88c | 2997 | |
8a9f3ccd | 2998 | /* |
69029cd5 | 2999 | * uncharge if !page_mapped(page) |
8a9f3ccd | 3000 | */ |
8c7c6e34 | 3001 | static struct mem_cgroup * |
69029cd5 | 3002 | __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) |
8a9f3ccd | 3003 | { |
8c7c6e34 | 3004 | struct mem_cgroup *mem = NULL; |
7ec99d62 JW |
3005 | unsigned int nr_pages = 1; |
3006 | struct page_cgroup *pc; | |
8a9f3ccd | 3007 | |
f8d66542 | 3008 | if (mem_cgroup_disabled()) |
8c7c6e34 | 3009 | return NULL; |
4077960e | 3010 | |
d13d1443 | 3011 | if (PageSwapCache(page)) |
8c7c6e34 | 3012 | return NULL; |
d13d1443 | 3013 | |
37c2ac78 | 3014 | if (PageTransHuge(page)) { |
7ec99d62 | 3015 | nr_pages <<= compound_order(page); |
37c2ac78 AA |
3016 | VM_BUG_ON(!PageTransHuge(page)); |
3017 | } | |
8697d331 | 3018 | /* |
3c541e14 | 3019 | * Check if our page_cgroup is valid |
8697d331 | 3020 | */ |
52d4b9ac KH |
3021 | pc = lookup_page_cgroup(page); |
3022 | if (unlikely(!pc || !PageCgroupUsed(pc))) | |
8c7c6e34 | 3023 | return NULL; |
b9c565d5 | 3024 | |
52d4b9ac | 3025 | lock_page_cgroup(pc); |
d13d1443 | 3026 | |
8c7c6e34 KH |
3027 | mem = pc->mem_cgroup; |
3028 | ||
d13d1443 KH |
3029 | if (!PageCgroupUsed(pc)) |
3030 | goto unlock_out; | |
3031 | ||
3032 | switch (ctype) { | |
3033 | case MEM_CGROUP_CHARGE_TYPE_MAPPED: | |
8a9478ca | 3034 | case MEM_CGROUP_CHARGE_TYPE_DROP: |
ac39cf8c AM |
3035 | /* See mem_cgroup_prepare_migration() */ |
3036 | if (page_mapped(page) || PageCgroupMigration(pc)) | |
d13d1443 KH |
3037 | goto unlock_out; |
3038 | break; | |
3039 | case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: | |
3040 | if (!PageAnon(page)) { /* Shared memory */ | |
3041 | if (page->mapping && !page_is_file_cache(page)) | |
3042 | goto unlock_out; | |
3043 | } else if (page_mapped(page)) /* Anon */ | |
3044 | goto unlock_out; | |
3045 | break; | |
3046 | default: | |
3047 | break; | |
52d4b9ac | 3048 | } |
d13d1443 | 3049 | |
7ec99d62 | 3050 | mem_cgroup_charge_statistics(mem, PageCgroupCache(pc), -nr_pages); |
04046e1a | 3051 | |
52d4b9ac | 3052 | ClearPageCgroupUsed(pc); |
544122e5 KH |
3053 | /* |
3054 | * pc->mem_cgroup is not cleared here. It will be accessed when it's | |
3055 | * freed from LRU. This is safe because uncharged page is expected not | |
3056 | * to be reused (freed soon). Exception is SwapCache, it's handled by | |
3057 | * special functions. | |
3058 | */ | |
b9c565d5 | 3059 | |
52d4b9ac | 3060 | unlock_page_cgroup(pc); |
f75ca962 KH |
3061 | /* |
3062 | * even after unlock, we have mem->res.usage here and this memcg | |
3063 | * will never be freed. | |
3064 | */ | |
d2265e6f | 3065 | memcg_check_events(mem, page); |
f75ca962 KH |
3066 | if (do_swap_account && ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) { |
3067 | mem_cgroup_swap_statistics(mem, true); | |
3068 | mem_cgroup_get(mem); | |
3069 | } | |
3070 | if (!mem_cgroup_is_root(mem)) | |
7ec99d62 | 3071 | mem_cgroup_do_uncharge(mem, nr_pages, ctype); |
6d12e2d8 | 3072 | |
8c7c6e34 | 3073 | return mem; |
d13d1443 KH |
3074 | |
3075 | unlock_out: | |
3076 | unlock_page_cgroup(pc); | |
8c7c6e34 | 3077 | return NULL; |
3c541e14 BS |
3078 | } |
3079 | ||
69029cd5 KH |
3080 | void mem_cgroup_uncharge_page(struct page *page) |
3081 | { | |
52d4b9ac KH |
3082 | /* early check. */ |
3083 | if (page_mapped(page)) | |
3084 | return; | |
3085 | if (page->mapping && !PageAnon(page)) | |
3086 | return; | |
69029cd5 KH |
3087 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED); |
3088 | } | |
3089 | ||
3090 | void mem_cgroup_uncharge_cache_page(struct page *page) | |
3091 | { | |
3092 | VM_BUG_ON(page_mapped(page)); | |
b7abea96 | 3093 | VM_BUG_ON(page->mapping); |
69029cd5 KH |
3094 | __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); |
3095 | } | |
3096 | ||
569b846d KH |
3097 | /* |
3098 | * Batch_start/batch_end is called in unmap_page_range/invlidate/trucate. | |
3099 | * In that cases, pages are freed continuously and we can expect pages | |
3100 | * are in the same memcg. All these calls itself limits the number of | |
3101 | * pages freed at once, then uncharge_start/end() is called properly. | |
3102 | * This may be called prural(2) times in a context, | |
3103 | */ | |
3104 | ||
3105 | void mem_cgroup_uncharge_start(void) | |
3106 | { | |
3107 | current->memcg_batch.do_batch++; | |
3108 | /* We can do nest. */ | |
3109 | if (current->memcg_batch.do_batch == 1) { | |
3110 | current->memcg_batch.memcg = NULL; | |
7ffd4ca7 JW |
3111 | current->memcg_batch.nr_pages = 0; |
3112 | current->memcg_batch.memsw_nr_pages = 0; | |
569b846d KH |
3113 | } |
3114 | } | |
3115 | ||
3116 | void mem_cgroup_uncharge_end(void) | |
3117 | { | |
3118 | struct memcg_batch_info *batch = ¤t->memcg_batch; | |
3119 | ||
3120 | if (!batch->do_batch) | |
3121 | return; | |
3122 | ||
3123 | batch->do_batch--; | |
3124 | if (batch->do_batch) /* If stacked, do nothing. */ | |
3125 | return; | |
3126 | ||
3127 | if (!batch->memcg) | |
3128 | return; | |
3129 | /* | |
3130 | * This "batch->memcg" is valid without any css_get/put etc... | |
3131 | * bacause we hide charges behind us. | |
3132 | */ | |
7ffd4ca7 JW |
3133 | if (batch->nr_pages) |
3134 | res_counter_uncharge(&batch->memcg->res, | |
3135 | batch->nr_pages * PAGE_SIZE); | |
3136 | if (batch->memsw_nr_pages) | |
3137 | res_counter_uncharge(&batch->memcg->memsw, | |
3138 | batch->memsw_nr_pages * PAGE_SIZE); | |
3c11ecf4 | 3139 | memcg_oom_recover(batch->memcg); |
569b846d KH |
3140 | /* forget this pointer (for sanity check) */ |
3141 | batch->memcg = NULL; | |
3142 | } | |
3143 | ||
e767e056 | 3144 | #ifdef CONFIG_SWAP |
8c7c6e34 | 3145 | /* |
e767e056 | 3146 | * called after __delete_from_swap_cache() and drop "page" account. |
8c7c6e34 KH |
3147 | * memcg information is recorded to swap_cgroup of "ent" |
3148 | */ | |
8a9478ca KH |
3149 | void |
3150 | mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout) | |
8c7c6e34 KH |
3151 | { |
3152 | struct mem_cgroup *memcg; | |
8a9478ca KH |
3153 | int ctype = MEM_CGROUP_CHARGE_TYPE_SWAPOUT; |
3154 | ||
3155 | if (!swapout) /* this was a swap cache but the swap is unused ! */ | |
3156 | ctype = MEM_CGROUP_CHARGE_TYPE_DROP; | |
3157 | ||
3158 | memcg = __mem_cgroup_uncharge_common(page, ctype); | |
8c7c6e34 | 3159 | |
f75ca962 KH |
3160 | /* |
3161 | * record memcg information, if swapout && memcg != NULL, | |
3162 | * mem_cgroup_get() was called in uncharge(). | |
3163 | */ | |
3164 | if (do_swap_account && swapout && memcg) | |
a3b2d692 | 3165 | swap_cgroup_record(ent, css_id(&memcg->css)); |
8c7c6e34 | 3166 | } |
e767e056 | 3167 | #endif |
8c7c6e34 KH |
3168 | |
3169 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
3170 | /* | |
3171 | * called from swap_entry_free(). remove record in swap_cgroup and | |
3172 | * uncharge "memsw" account. | |
3173 | */ | |
3174 | void mem_cgroup_uncharge_swap(swp_entry_t ent) | |
d13d1443 | 3175 | { |
8c7c6e34 | 3176 | struct mem_cgroup *memcg; |
a3b2d692 | 3177 | unsigned short id; |
8c7c6e34 KH |
3178 | |
3179 | if (!do_swap_account) | |
3180 | return; | |
3181 | ||
a3b2d692 KH |
3182 | id = swap_cgroup_record(ent, 0); |
3183 | rcu_read_lock(); | |
3184 | memcg = mem_cgroup_lookup(id); | |
8c7c6e34 | 3185 | if (memcg) { |
a3b2d692 KH |
3186 | /* |
3187 | * We uncharge this because swap is freed. | |
3188 | * This memcg can be obsolete one. We avoid calling css_tryget | |
3189 | */ | |
0c3e73e8 | 3190 | if (!mem_cgroup_is_root(memcg)) |
4e649152 | 3191 | res_counter_uncharge(&memcg->memsw, PAGE_SIZE); |
0c3e73e8 | 3192 | mem_cgroup_swap_statistics(memcg, false); |
8c7c6e34 KH |
3193 | mem_cgroup_put(memcg); |
3194 | } | |
a3b2d692 | 3195 | rcu_read_unlock(); |
d13d1443 | 3196 | } |
02491447 DN |
3197 | |
3198 | /** | |
3199 | * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. | |
3200 | * @entry: swap entry to be moved | |
3201 | * @from: mem_cgroup which the entry is moved from | |
3202 | * @to: mem_cgroup which the entry is moved to | |
483c30b5 | 3203 | * @need_fixup: whether we should fixup res_counters and refcounts. |
02491447 DN |
3204 | * |
3205 | * It succeeds only when the swap_cgroup's record for this entry is the same | |
3206 | * as the mem_cgroup's id of @from. | |
3207 | * | |
3208 | * Returns 0 on success, -EINVAL on failure. | |
3209 | * | |
3210 | * The caller must have charged to @to, IOW, called res_counter_charge() about | |
3211 | * both res and memsw, and called css_get(). | |
3212 | */ | |
3213 | static int mem_cgroup_move_swap_account(swp_entry_t entry, | |
483c30b5 | 3214 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
02491447 DN |
3215 | { |
3216 | unsigned short old_id, new_id; | |
3217 | ||
3218 | old_id = css_id(&from->css); | |
3219 | new_id = css_id(&to->css); | |
3220 | ||
3221 | if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { | |
02491447 | 3222 | mem_cgroup_swap_statistics(from, false); |
483c30b5 | 3223 | mem_cgroup_swap_statistics(to, true); |
02491447 | 3224 | /* |
483c30b5 DN |
3225 | * This function is only called from task migration context now. |
3226 | * It postpones res_counter and refcount handling till the end | |
3227 | * of task migration(mem_cgroup_clear_mc()) for performance | |
3228 | * improvement. But we cannot postpone mem_cgroup_get(to) | |
3229 | * because if the process that has been moved to @to does | |
3230 | * swap-in, the refcount of @to might be decreased to 0. | |
02491447 | 3231 | */ |
02491447 | 3232 | mem_cgroup_get(to); |
483c30b5 DN |
3233 | if (need_fixup) { |
3234 | if (!mem_cgroup_is_root(from)) | |
3235 | res_counter_uncharge(&from->memsw, PAGE_SIZE); | |
3236 | mem_cgroup_put(from); | |
3237 | /* | |
3238 | * we charged both to->res and to->memsw, so we should | |
3239 | * uncharge to->res. | |
3240 | */ | |
3241 | if (!mem_cgroup_is_root(to)) | |
3242 | res_counter_uncharge(&to->res, PAGE_SIZE); | |
483c30b5 | 3243 | } |
02491447 DN |
3244 | return 0; |
3245 | } | |
3246 | return -EINVAL; | |
3247 | } | |
3248 | #else | |
3249 | static inline int mem_cgroup_move_swap_account(swp_entry_t entry, | |
483c30b5 | 3250 | struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) |
02491447 DN |
3251 | { |
3252 | return -EINVAL; | |
3253 | } | |
8c7c6e34 | 3254 | #endif |
d13d1443 | 3255 | |
ae41be37 | 3256 | /* |
01b1ae63 KH |
3257 | * Before starting migration, account PAGE_SIZE to mem_cgroup that the old |
3258 | * page belongs to. | |
ae41be37 | 3259 | */ |
ac39cf8c | 3260 | int mem_cgroup_prepare_migration(struct page *page, |
ef6a3c63 | 3261 | struct page *newpage, struct mem_cgroup **ptr, gfp_t gfp_mask) |
ae41be37 | 3262 | { |
e8589cc1 | 3263 | struct mem_cgroup *mem = NULL; |
7ec99d62 | 3264 | struct page_cgroup *pc; |
ac39cf8c | 3265 | enum charge_type ctype; |
e8589cc1 | 3266 | int ret = 0; |
8869b8f6 | 3267 | |
56039efa KH |
3268 | *ptr = NULL; |
3269 | ||
ec168510 | 3270 | VM_BUG_ON(PageTransHuge(page)); |
f8d66542 | 3271 | if (mem_cgroup_disabled()) |
4077960e BS |
3272 | return 0; |
3273 | ||
52d4b9ac KH |
3274 | pc = lookup_page_cgroup(page); |
3275 | lock_page_cgroup(pc); | |
3276 | if (PageCgroupUsed(pc)) { | |
e8589cc1 KH |
3277 | mem = pc->mem_cgroup; |
3278 | css_get(&mem->css); | |
ac39cf8c AM |
3279 | /* |
3280 | * At migrating an anonymous page, its mapcount goes down | |
3281 | * to 0 and uncharge() will be called. But, even if it's fully | |
3282 | * unmapped, migration may fail and this page has to be | |
3283 | * charged again. We set MIGRATION flag here and delay uncharge | |
3284 | * until end_migration() is called | |
3285 | * | |
3286 | * Corner Case Thinking | |
3287 | * A) | |
3288 | * When the old page was mapped as Anon and it's unmap-and-freed | |
3289 | * while migration was ongoing. | |
3290 | * If unmap finds the old page, uncharge() of it will be delayed | |
3291 | * until end_migration(). If unmap finds a new page, it's | |
3292 | * uncharged when it make mapcount to be 1->0. If unmap code | |
3293 | * finds swap_migration_entry, the new page will not be mapped | |
3294 | * and end_migration() will find it(mapcount==0). | |
3295 | * | |
3296 | * B) | |
3297 | * When the old page was mapped but migraion fails, the kernel | |
3298 | * remaps it. A charge for it is kept by MIGRATION flag even | |
3299 | * if mapcount goes down to 0. We can do remap successfully | |
3300 | * without charging it again. | |
3301 | * | |
3302 | * C) | |
3303 | * The "old" page is under lock_page() until the end of | |
3304 | * migration, so, the old page itself will not be swapped-out. | |
3305 | * If the new page is swapped out before end_migraton, our | |
3306 | * hook to usual swap-out path will catch the event. | |
3307 | */ | |
3308 | if (PageAnon(page)) | |
3309 | SetPageCgroupMigration(pc); | |
e8589cc1 | 3310 | } |
52d4b9ac | 3311 | unlock_page_cgroup(pc); |
ac39cf8c AM |
3312 | /* |
3313 | * If the page is not charged at this point, | |
3314 | * we return here. | |
3315 | */ | |
3316 | if (!mem) | |
3317 | return 0; | |
01b1ae63 | 3318 | |
93d5c9be | 3319 | *ptr = mem; |
7ec99d62 | 3320 | ret = __mem_cgroup_try_charge(NULL, gfp_mask, 1, ptr, false); |
ac39cf8c AM |
3321 | css_put(&mem->css);/* drop extra refcnt */ |
3322 | if (ret || *ptr == NULL) { | |
3323 | if (PageAnon(page)) { | |
3324 | lock_page_cgroup(pc); | |
3325 | ClearPageCgroupMigration(pc); | |
3326 | unlock_page_cgroup(pc); | |
3327 | /* | |
3328 | * The old page may be fully unmapped while we kept it. | |
3329 | */ | |
3330 | mem_cgroup_uncharge_page(page); | |
3331 | } | |
3332 | return -ENOMEM; | |
e8589cc1 | 3333 | } |
ac39cf8c AM |
3334 | /* |
3335 | * We charge new page before it's used/mapped. So, even if unlock_page() | |
3336 | * is called before end_migration, we can catch all events on this new | |
3337 | * page. In the case new page is migrated but not remapped, new page's | |
3338 | * mapcount will be finally 0 and we call uncharge in end_migration(). | |
3339 | */ | |
3340 | pc = lookup_page_cgroup(newpage); | |
3341 | if (PageAnon(page)) | |
3342 | ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED; | |
3343 | else if (page_is_file_cache(page)) | |
3344 | ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; | |
3345 | else | |
3346 | ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; | |
7ec99d62 | 3347 | __mem_cgroup_commit_charge(mem, page, 1, pc, ctype); |
e8589cc1 | 3348 | return ret; |
ae41be37 | 3349 | } |
8869b8f6 | 3350 | |
69029cd5 | 3351 | /* remove redundant charge if migration failed*/ |
01b1ae63 | 3352 | void mem_cgroup_end_migration(struct mem_cgroup *mem, |
50de1dd9 | 3353 | struct page *oldpage, struct page *newpage, bool migration_ok) |
ae41be37 | 3354 | { |
ac39cf8c | 3355 | struct page *used, *unused; |
01b1ae63 | 3356 | struct page_cgroup *pc; |
01b1ae63 KH |
3357 | |
3358 | if (!mem) | |
3359 | return; | |
ac39cf8c | 3360 | /* blocks rmdir() */ |
88703267 | 3361 | cgroup_exclude_rmdir(&mem->css); |
50de1dd9 | 3362 | if (!migration_ok) { |
ac39cf8c AM |
3363 | used = oldpage; |
3364 | unused = newpage; | |
01b1ae63 | 3365 | } else { |
ac39cf8c | 3366 | used = newpage; |
01b1ae63 KH |
3367 | unused = oldpage; |
3368 | } | |
69029cd5 | 3369 | /* |
ac39cf8c AM |
3370 | * We disallowed uncharge of pages under migration because mapcount |
3371 | * of the page goes down to zero, temporarly. | |
3372 | * Clear the flag and check the page should be charged. | |
01b1ae63 | 3373 | */ |
ac39cf8c AM |
3374 | pc = lookup_page_cgroup(oldpage); |
3375 | lock_page_cgroup(pc); | |
3376 | ClearPageCgroupMigration(pc); | |
3377 | unlock_page_cgroup(pc); | |
01b1ae63 | 3378 | |
ac39cf8c AM |
3379 | __mem_cgroup_uncharge_common(unused, MEM_CGROUP_CHARGE_TYPE_FORCE); |
3380 | ||
01b1ae63 | 3381 | /* |
ac39cf8c AM |
3382 | * If a page is a file cache, radix-tree replacement is very atomic |
3383 | * and we can skip this check. When it was an Anon page, its mapcount | |
3384 | * goes down to 0. But because we added MIGRATION flage, it's not | |
3385 | * uncharged yet. There are several case but page->mapcount check | |
3386 | * and USED bit check in mem_cgroup_uncharge_page() will do enough | |
3387 | * check. (see prepare_charge() also) | |
69029cd5 | 3388 | */ |
ac39cf8c AM |
3389 | if (PageAnon(used)) |
3390 | mem_cgroup_uncharge_page(used); | |
88703267 | 3391 | /* |
ac39cf8c AM |
3392 | * At migration, we may charge account against cgroup which has no |
3393 | * tasks. | |
88703267 KH |
3394 | * So, rmdir()->pre_destroy() can be called while we do this charge. |
3395 | * In that case, we need to call pre_destroy() again. check it here. | |
3396 | */ | |
3397 | cgroup_release_and_wakeup_rmdir(&mem->css); | |
ae41be37 | 3398 | } |
78fb7466 | 3399 | |
c9b0ed51 | 3400 | /* |
ae3abae6 DN |
3401 | * A call to try to shrink memory usage on charge failure at shmem's swapin. |
3402 | * Calling hierarchical_reclaim is not enough because we should update | |
3403 | * last_oom_jiffies to prevent pagefault_out_of_memory from invoking global OOM. | |
3404 | * Moreover considering hierarchy, we should reclaim from the mem_over_limit, | |
3405 | * not from the memcg which this page would be charged to. | |
3406 | * try_charge_swapin does all of these works properly. | |
c9b0ed51 | 3407 | */ |
ae3abae6 | 3408 | int mem_cgroup_shmem_charge_fallback(struct page *page, |
b5a84319 KH |
3409 | struct mm_struct *mm, |
3410 | gfp_t gfp_mask) | |
c9b0ed51 | 3411 | { |
56039efa | 3412 | struct mem_cgroup *mem; |
ae3abae6 | 3413 | int ret; |
c9b0ed51 | 3414 | |
f8d66542 | 3415 | if (mem_cgroup_disabled()) |
cede86ac | 3416 | return 0; |
c9b0ed51 | 3417 | |
ae3abae6 DN |
3418 | ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); |
3419 | if (!ret) | |
3420 | mem_cgroup_cancel_charge_swapin(mem); /* it does !mem check */ | |
c9b0ed51 | 3421 | |
ae3abae6 | 3422 | return ret; |
c9b0ed51 KH |
3423 | } |
3424 | ||
f212ad7c DN |
3425 | #ifdef CONFIG_DEBUG_VM |
3426 | static struct page_cgroup *lookup_page_cgroup_used(struct page *page) | |
3427 | { | |
3428 | struct page_cgroup *pc; | |
3429 | ||
3430 | pc = lookup_page_cgroup(page); | |
3431 | if (likely(pc) && PageCgroupUsed(pc)) | |
3432 | return pc; | |
3433 | return NULL; | |
3434 | } | |
3435 | ||
3436 | bool mem_cgroup_bad_page_check(struct page *page) | |
3437 | { | |
3438 | if (mem_cgroup_disabled()) | |
3439 | return false; | |
3440 | ||
3441 | return lookup_page_cgroup_used(page) != NULL; | |
3442 | } | |
3443 | ||
3444 | void mem_cgroup_print_bad_page(struct page *page) | |
3445 | { | |
3446 | struct page_cgroup *pc; | |
3447 | ||
3448 | pc = lookup_page_cgroup_used(page); | |
3449 | if (pc) { | |
3450 | int ret = -1; | |
3451 | char *path; | |
3452 | ||
3453 | printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p", | |
3454 | pc, pc->flags, pc->mem_cgroup); | |
3455 | ||
3456 | path = kmalloc(PATH_MAX, GFP_KERNEL); | |
3457 | if (path) { | |
3458 | rcu_read_lock(); | |
3459 | ret = cgroup_path(pc->mem_cgroup->css.cgroup, | |
3460 | path, PATH_MAX); | |
3461 | rcu_read_unlock(); | |
3462 | } | |
3463 | ||
3464 | printk(KERN_CONT "(%s)\n", | |
3465 | (ret < 0) ? "cannot get the path" : path); | |
3466 | kfree(path); | |
3467 | } | |
3468 | } | |
3469 | #endif | |
3470 | ||
8c7c6e34 KH |
3471 | static DEFINE_MUTEX(set_limit_mutex); |
3472 | ||
d38d2a75 | 3473 | static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, |
8c7c6e34 | 3474 | unsigned long long val) |
628f4235 | 3475 | { |
81d39c20 | 3476 | int retry_count; |
3c11ecf4 | 3477 | u64 memswlimit, memlimit; |
628f4235 | 3478 | int ret = 0; |
81d39c20 KH |
3479 | int children = mem_cgroup_count_children(memcg); |
3480 | u64 curusage, oldusage; | |
3c11ecf4 | 3481 | int enlarge; |
81d39c20 KH |
3482 | |
3483 | /* | |
3484 | * For keeping hierarchical_reclaim simple, how long we should retry | |
3485 | * is depends on callers. We set our retry-count to be function | |
3486 | * of # of children which we should visit in this loop. | |
3487 | */ | |
3488 | retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; | |
3489 | ||
3490 | oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); | |
628f4235 | 3491 | |
3c11ecf4 | 3492 | enlarge = 0; |
8c7c6e34 | 3493 | while (retry_count) { |
628f4235 KH |
3494 | if (signal_pending(current)) { |
3495 | ret = -EINTR; | |
3496 | break; | |
3497 | } | |
8c7c6e34 KH |
3498 | /* |
3499 | * Rather than hide all in some function, I do this in | |
3500 | * open coded manner. You see what this really does. | |
3501 | * We have to guarantee mem->res.limit < mem->memsw.limit. | |
3502 | */ | |
3503 | mutex_lock(&set_limit_mutex); | |
3504 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
3505 | if (memswlimit < val) { | |
3506 | ret = -EINVAL; | |
3507 | mutex_unlock(&set_limit_mutex); | |
628f4235 KH |
3508 | break; |
3509 | } | |
3c11ecf4 KH |
3510 | |
3511 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3512 | if (memlimit < val) | |
3513 | enlarge = 1; | |
3514 | ||
8c7c6e34 | 3515 | ret = res_counter_set_limit(&memcg->res, val); |
22a668d7 KH |
3516 | if (!ret) { |
3517 | if (memswlimit == val) | |
3518 | memcg->memsw_is_minimum = true; | |
3519 | else | |
3520 | memcg->memsw_is_minimum = false; | |
3521 | } | |
8c7c6e34 KH |
3522 | mutex_unlock(&set_limit_mutex); |
3523 | ||
3524 | if (!ret) | |
3525 | break; | |
3526 | ||
aa20d489 | 3527 | mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, |
0ae5e89c YH |
3528 | MEM_CGROUP_RECLAIM_SHRINK, |
3529 | NULL); | |
81d39c20 KH |
3530 | curusage = res_counter_read_u64(&memcg->res, RES_USAGE); |
3531 | /* Usage is reduced ? */ | |
3532 | if (curusage >= oldusage) | |
3533 | retry_count--; | |
3534 | else | |
3535 | oldusage = curusage; | |
8c7c6e34 | 3536 | } |
3c11ecf4 KH |
3537 | if (!ret && enlarge) |
3538 | memcg_oom_recover(memcg); | |
14797e23 | 3539 | |
8c7c6e34 KH |
3540 | return ret; |
3541 | } | |
3542 | ||
338c8431 LZ |
3543 | static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, |
3544 | unsigned long long val) | |
8c7c6e34 | 3545 | { |
81d39c20 | 3546 | int retry_count; |
3c11ecf4 | 3547 | u64 memlimit, memswlimit, oldusage, curusage; |
81d39c20 KH |
3548 | int children = mem_cgroup_count_children(memcg); |
3549 | int ret = -EBUSY; | |
3c11ecf4 | 3550 | int enlarge = 0; |
8c7c6e34 | 3551 | |
81d39c20 KH |
3552 | /* see mem_cgroup_resize_res_limit */ |
3553 | retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; | |
3554 | oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); | |
8c7c6e34 KH |
3555 | while (retry_count) { |
3556 | if (signal_pending(current)) { | |
3557 | ret = -EINTR; | |
3558 | break; | |
3559 | } | |
3560 | /* | |
3561 | * Rather than hide all in some function, I do this in | |
3562 | * open coded manner. You see what this really does. | |
3563 | * We have to guarantee mem->res.limit < mem->memsw.limit. | |
3564 | */ | |
3565 | mutex_lock(&set_limit_mutex); | |
3566 | memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
3567 | if (memlimit > val) { | |
3568 | ret = -EINVAL; | |
3569 | mutex_unlock(&set_limit_mutex); | |
3570 | break; | |
3571 | } | |
3c11ecf4 KH |
3572 | memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); |
3573 | if (memswlimit < val) | |
3574 | enlarge = 1; | |
8c7c6e34 | 3575 | ret = res_counter_set_limit(&memcg->memsw, val); |
22a668d7 KH |
3576 | if (!ret) { |
3577 | if (memlimit == val) | |
3578 | memcg->memsw_is_minimum = true; | |
3579 | else | |
3580 | memcg->memsw_is_minimum = false; | |
3581 | } | |
8c7c6e34 KH |
3582 | mutex_unlock(&set_limit_mutex); |
3583 | ||
3584 | if (!ret) | |
3585 | break; | |
3586 | ||
4e416953 | 3587 | mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, |
75822b44 | 3588 | MEM_CGROUP_RECLAIM_NOSWAP | |
0ae5e89c YH |
3589 | MEM_CGROUP_RECLAIM_SHRINK, |
3590 | NULL); | |
8c7c6e34 | 3591 | curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); |
81d39c20 | 3592 | /* Usage is reduced ? */ |
8c7c6e34 | 3593 | if (curusage >= oldusage) |
628f4235 | 3594 | retry_count--; |
81d39c20 KH |
3595 | else |
3596 | oldusage = curusage; | |
628f4235 | 3597 | } |
3c11ecf4 KH |
3598 | if (!ret && enlarge) |
3599 | memcg_oom_recover(memcg); | |
628f4235 KH |
3600 | return ret; |
3601 | } | |
3602 | ||
4e416953 | 3603 | unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, |
0ae5e89c YH |
3604 | gfp_t gfp_mask, |
3605 | unsigned long *total_scanned) | |
4e416953 BS |
3606 | { |
3607 | unsigned long nr_reclaimed = 0; | |
3608 | struct mem_cgroup_per_zone *mz, *next_mz = NULL; | |
3609 | unsigned long reclaimed; | |
3610 | int loop = 0; | |
3611 | struct mem_cgroup_tree_per_zone *mctz; | |
ef8745c1 | 3612 | unsigned long long excess; |
0ae5e89c | 3613 | unsigned long nr_scanned; |
4e416953 BS |
3614 | |
3615 | if (order > 0) | |
3616 | return 0; | |
3617 | ||
00918b6a | 3618 | mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone)); |
4e416953 BS |
3619 | /* |
3620 | * This loop can run a while, specially if mem_cgroup's continuously | |
3621 | * keep exceeding their soft limit and putting the system under | |
3622 | * pressure | |
3623 | */ | |
3624 | do { | |
3625 | if (next_mz) | |
3626 | mz = next_mz; | |
3627 | else | |
3628 | mz = mem_cgroup_largest_soft_limit_node(mctz); | |
3629 | if (!mz) | |
3630 | break; | |
3631 | ||
0ae5e89c | 3632 | nr_scanned = 0; |
4e416953 BS |
3633 | reclaimed = mem_cgroup_hierarchical_reclaim(mz->mem, zone, |
3634 | gfp_mask, | |
0ae5e89c YH |
3635 | MEM_CGROUP_RECLAIM_SOFT, |
3636 | &nr_scanned); | |
4e416953 | 3637 | nr_reclaimed += reclaimed; |
0ae5e89c | 3638 | *total_scanned += nr_scanned; |
4e416953 BS |
3639 | spin_lock(&mctz->lock); |
3640 | ||
3641 | /* | |
3642 | * If we failed to reclaim anything from this memory cgroup | |
3643 | * it is time to move on to the next cgroup | |
3644 | */ | |
3645 | next_mz = NULL; | |
3646 | if (!reclaimed) { | |
3647 | do { | |
3648 | /* | |
3649 | * Loop until we find yet another one. | |
3650 | * | |
3651 | * By the time we get the soft_limit lock | |
3652 | * again, someone might have aded the | |
3653 | * group back on the RB tree. Iterate to | |
3654 | * make sure we get a different mem. | |
3655 | * mem_cgroup_largest_soft_limit_node returns | |
3656 | * NULL if no other cgroup is present on | |
3657 | * the tree | |
3658 | */ | |
3659 | next_mz = | |
3660 | __mem_cgroup_largest_soft_limit_node(mctz); | |
39cc98f1 | 3661 | if (next_mz == mz) |
4e416953 | 3662 | css_put(&next_mz->mem->css); |
39cc98f1 | 3663 | else /* next_mz == NULL or other memcg */ |
4e416953 BS |
3664 | break; |
3665 | } while (1); | |
3666 | } | |
4e416953 | 3667 | __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); |
ef8745c1 | 3668 | excess = res_counter_soft_limit_excess(&mz->mem->res); |
4e416953 BS |
3669 | /* |
3670 | * One school of thought says that we should not add | |
3671 | * back the node to the tree if reclaim returns 0. | |
3672 | * But our reclaim could return 0, simply because due | |
3673 | * to priority we are exposing a smaller subset of | |
3674 | * memory to reclaim from. Consider this as a longer | |
3675 | * term TODO. | |
3676 | */ | |
ef8745c1 KH |
3677 | /* If excess == 0, no tree ops */ |
3678 | __mem_cgroup_insert_exceeded(mz->mem, mz, mctz, excess); | |
4e416953 BS |
3679 | spin_unlock(&mctz->lock); |
3680 | css_put(&mz->mem->css); | |
3681 | loop++; | |
3682 | /* | |
3683 | * Could not reclaim anything and there are no more | |
3684 | * mem cgroups to try or we seem to be looping without | |
3685 | * reclaiming anything. | |
3686 | */ | |
3687 | if (!nr_reclaimed && | |
3688 | (next_mz == NULL || | |
3689 | loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) | |
3690 | break; | |
3691 | } while (!nr_reclaimed); | |
3692 | if (next_mz) | |
3693 | css_put(&next_mz->mem->css); | |
3694 | return nr_reclaimed; | |
3695 | } | |
3696 | ||
cc847582 KH |
3697 | /* |
3698 | * This routine traverse page_cgroup in given list and drop them all. | |
cc847582 KH |
3699 | * *And* this routine doesn't reclaim page itself, just removes page_cgroup. |
3700 | */ | |
f817ed48 | 3701 | static int mem_cgroup_force_empty_list(struct mem_cgroup *mem, |
08e552c6 | 3702 | int node, int zid, enum lru_list lru) |
cc847582 | 3703 | { |
08e552c6 KH |
3704 | struct zone *zone; |
3705 | struct mem_cgroup_per_zone *mz; | |
f817ed48 | 3706 | struct page_cgroup *pc, *busy; |
08e552c6 | 3707 | unsigned long flags, loop; |
072c56c1 | 3708 | struct list_head *list; |
f817ed48 | 3709 | int ret = 0; |
072c56c1 | 3710 | |
08e552c6 KH |
3711 | zone = &NODE_DATA(node)->node_zones[zid]; |
3712 | mz = mem_cgroup_zoneinfo(mem, node, zid); | |
b69408e8 | 3713 | list = &mz->lists[lru]; |
cc847582 | 3714 | |
f817ed48 KH |
3715 | loop = MEM_CGROUP_ZSTAT(mz, lru); |
3716 | /* give some margin against EBUSY etc...*/ | |
3717 | loop += 256; | |
3718 | busy = NULL; | |
3719 | while (loop--) { | |
5564e88b JW |
3720 | struct page *page; |
3721 | ||
f817ed48 | 3722 | ret = 0; |
08e552c6 | 3723 | spin_lock_irqsave(&zone->lru_lock, flags); |
f817ed48 | 3724 | if (list_empty(list)) { |
08e552c6 | 3725 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
52d4b9ac | 3726 | break; |
f817ed48 KH |
3727 | } |
3728 | pc = list_entry(list->prev, struct page_cgroup, lru); | |
3729 | if (busy == pc) { | |
3730 | list_move(&pc->lru, list); | |
648bcc77 | 3731 | busy = NULL; |
08e552c6 | 3732 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 KH |
3733 | continue; |
3734 | } | |
08e552c6 | 3735 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
f817ed48 | 3736 | |
6b3ae58e | 3737 | page = lookup_cgroup_page(pc); |
5564e88b JW |
3738 | |
3739 | ret = mem_cgroup_move_parent(page, pc, mem, GFP_KERNEL); | |
f817ed48 | 3740 | if (ret == -ENOMEM) |
52d4b9ac | 3741 | break; |
f817ed48 KH |
3742 | |
3743 | if (ret == -EBUSY || ret == -EINVAL) { | |
3744 | /* found lock contention or "pc" is obsolete. */ | |
3745 | busy = pc; | |
3746 | cond_resched(); | |
3747 | } else | |
3748 | busy = NULL; | |
cc847582 | 3749 | } |
08e552c6 | 3750 | |
f817ed48 KH |
3751 | if (!ret && !list_empty(list)) |
3752 | return -EBUSY; | |
3753 | return ret; | |
cc847582 KH |
3754 | } |
3755 | ||
3756 | /* | |
3757 | * make mem_cgroup's charge to be 0 if there is no task. | |
3758 | * This enables deleting this mem_cgroup. | |
3759 | */ | |
c1e862c1 | 3760 | static int mem_cgroup_force_empty(struct mem_cgroup *mem, bool free_all) |
cc847582 | 3761 | { |
f817ed48 KH |
3762 | int ret; |
3763 | int node, zid, shrink; | |
3764 | int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; | |
c1e862c1 | 3765 | struct cgroup *cgrp = mem->css.cgroup; |
8869b8f6 | 3766 | |
cc847582 | 3767 | css_get(&mem->css); |
f817ed48 KH |
3768 | |
3769 | shrink = 0; | |
c1e862c1 KH |
3770 | /* should free all ? */ |
3771 | if (free_all) | |
3772 | goto try_to_free; | |
f817ed48 | 3773 | move_account: |
fce66477 | 3774 | do { |
f817ed48 | 3775 | ret = -EBUSY; |
c1e862c1 KH |
3776 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children)) |
3777 | goto out; | |
3778 | ret = -EINTR; | |
3779 | if (signal_pending(current)) | |
cc847582 | 3780 | goto out; |
52d4b9ac KH |
3781 | /* This is for making all *used* pages to be on LRU. */ |
3782 | lru_add_drain_all(); | |
cdec2e42 | 3783 | drain_all_stock_sync(); |
f817ed48 | 3784 | ret = 0; |
32047e2a | 3785 | mem_cgroup_start_move(mem); |
299b4eaa | 3786 | for_each_node_state(node, N_HIGH_MEMORY) { |
f817ed48 | 3787 | for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { |
b69408e8 | 3788 | enum lru_list l; |
f817ed48 KH |
3789 | for_each_lru(l) { |
3790 | ret = mem_cgroup_force_empty_list(mem, | |
08e552c6 | 3791 | node, zid, l); |
f817ed48 KH |
3792 | if (ret) |
3793 | break; | |
3794 | } | |
1ecaab2b | 3795 | } |
f817ed48 KH |
3796 | if (ret) |
3797 | break; | |
3798 | } | |
32047e2a | 3799 | mem_cgroup_end_move(mem); |
3c11ecf4 | 3800 | memcg_oom_recover(mem); |
f817ed48 KH |
3801 | /* it seems parent cgroup doesn't have enough mem */ |
3802 | if (ret == -ENOMEM) | |
3803 | goto try_to_free; | |
52d4b9ac | 3804 | cond_resched(); |
fce66477 DN |
3805 | /* "ret" should also be checked to ensure all lists are empty. */ |
3806 | } while (mem->res.usage > 0 || ret); | |
cc847582 KH |
3807 | out: |
3808 | css_put(&mem->css); | |
3809 | return ret; | |
f817ed48 KH |
3810 | |
3811 | try_to_free: | |
c1e862c1 KH |
3812 | /* returns EBUSY if there is a task or if we come here twice. */ |
3813 | if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) { | |
f817ed48 KH |
3814 | ret = -EBUSY; |
3815 | goto out; | |
3816 | } | |
c1e862c1 KH |
3817 | /* we call try-to-free pages for make this cgroup empty */ |
3818 | lru_add_drain_all(); | |
f817ed48 KH |
3819 | /* try to free all pages in this cgroup */ |
3820 | shrink = 1; | |
3821 | while (nr_retries && mem->res.usage > 0) { | |
3822 | int progress; | |
c1e862c1 KH |
3823 | |
3824 | if (signal_pending(current)) { | |
3825 | ret = -EINTR; | |
3826 | goto out; | |
3827 | } | |
a7885eb8 KM |
3828 | progress = try_to_free_mem_cgroup_pages(mem, GFP_KERNEL, |
3829 | false, get_swappiness(mem)); | |
c1e862c1 | 3830 | if (!progress) { |
f817ed48 | 3831 | nr_retries--; |
c1e862c1 | 3832 | /* maybe some writeback is necessary */ |
8aa7e847 | 3833 | congestion_wait(BLK_RW_ASYNC, HZ/10); |
c1e862c1 | 3834 | } |
f817ed48 KH |
3835 | |
3836 | } | |
08e552c6 | 3837 | lru_add_drain(); |
f817ed48 | 3838 | /* try move_account...there may be some *locked* pages. */ |
fce66477 | 3839 | goto move_account; |
cc847582 KH |
3840 | } |
3841 | ||
c1e862c1 KH |
3842 | int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event) |
3843 | { | |
3844 | return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true); | |
3845 | } | |
3846 | ||
3847 | ||
18f59ea7 BS |
3848 | static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft) |
3849 | { | |
3850 | return mem_cgroup_from_cont(cont)->use_hierarchy; | |
3851 | } | |
3852 | ||
3853 | static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft, | |
3854 | u64 val) | |
3855 | { | |
3856 | int retval = 0; | |
3857 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); | |
3858 | struct cgroup *parent = cont->parent; | |
3859 | struct mem_cgroup *parent_mem = NULL; | |
3860 | ||
3861 | if (parent) | |
3862 | parent_mem = mem_cgroup_from_cont(parent); | |
3863 | ||
3864 | cgroup_lock(); | |
3865 | /* | |
af901ca1 | 3866 | * If parent's use_hierarchy is set, we can't make any modifications |
18f59ea7 BS |
3867 | * in the child subtrees. If it is unset, then the change can |
3868 | * occur, provided the current cgroup has no children. | |
3869 | * | |
3870 | * For the root cgroup, parent_mem is NULL, we allow value to be | |
3871 | * set if there are no children. | |
3872 | */ | |
3873 | if ((!parent_mem || !parent_mem->use_hierarchy) && | |
3874 | (val == 1 || val == 0)) { | |
3875 | if (list_empty(&cont->children)) | |
3876 | mem->use_hierarchy = val; | |
3877 | else | |
3878 | retval = -EBUSY; | |
3879 | } else | |
3880 | retval = -EINVAL; | |
3881 | cgroup_unlock(); | |
3882 | ||
3883 | return retval; | |
3884 | } | |
3885 | ||
0c3e73e8 | 3886 | |
7a159cc9 JW |
3887 | static unsigned long mem_cgroup_recursive_stat(struct mem_cgroup *mem, |
3888 | enum mem_cgroup_stat_index idx) | |
0c3e73e8 | 3889 | { |
7d74b06f | 3890 | struct mem_cgroup *iter; |
7a159cc9 | 3891 | long val = 0; |
0c3e73e8 | 3892 | |
7a159cc9 | 3893 | /* Per-cpu values can be negative, use a signed accumulator */ |
7d74b06f KH |
3894 | for_each_mem_cgroup_tree(iter, mem) |
3895 | val += mem_cgroup_read_stat(iter, idx); | |
3896 | ||
3897 | if (val < 0) /* race ? */ | |
3898 | val = 0; | |
3899 | return val; | |
0c3e73e8 BS |
3900 | } |
3901 | ||
104f3928 KS |
3902 | static inline u64 mem_cgroup_usage(struct mem_cgroup *mem, bool swap) |
3903 | { | |
7d74b06f | 3904 | u64 val; |
104f3928 KS |
3905 | |
3906 | if (!mem_cgroup_is_root(mem)) { | |
3907 | if (!swap) | |
3908 | return res_counter_read_u64(&mem->res, RES_USAGE); | |
3909 | else | |
3910 | return res_counter_read_u64(&mem->memsw, RES_USAGE); | |
3911 | } | |
3912 | ||
7a159cc9 JW |
3913 | val = mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_CACHE); |
3914 | val += mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_RSS); | |
104f3928 | 3915 | |
7d74b06f | 3916 | if (swap) |
7a159cc9 | 3917 | val += mem_cgroup_recursive_stat(mem, MEM_CGROUP_STAT_SWAPOUT); |
104f3928 KS |
3918 | |
3919 | return val << PAGE_SHIFT; | |
3920 | } | |
3921 | ||
2c3daa72 | 3922 | static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) |
8cdea7c0 | 3923 | { |
8c7c6e34 | 3924 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
104f3928 | 3925 | u64 val; |
8c7c6e34 KH |
3926 | int type, name; |
3927 | ||
3928 | type = MEMFILE_TYPE(cft->private); | |
3929 | name = MEMFILE_ATTR(cft->private); | |
3930 | switch (type) { | |
3931 | case _MEM: | |
104f3928 KS |
3932 | if (name == RES_USAGE) |
3933 | val = mem_cgroup_usage(mem, false); | |
3934 | else | |
0c3e73e8 | 3935 | val = res_counter_read_u64(&mem->res, name); |
8c7c6e34 KH |
3936 | break; |
3937 | case _MEMSWAP: | |
104f3928 KS |
3938 | if (name == RES_USAGE) |
3939 | val = mem_cgroup_usage(mem, true); | |
3940 | else | |
0c3e73e8 | 3941 | val = res_counter_read_u64(&mem->memsw, name); |
8c7c6e34 KH |
3942 | break; |
3943 | default: | |
3944 | BUG(); | |
3945 | break; | |
3946 | } | |
3947 | return val; | |
8cdea7c0 | 3948 | } |
628f4235 KH |
3949 | /* |
3950 | * The user of this function is... | |
3951 | * RES_LIMIT. | |
3952 | */ | |
856c13aa PM |
3953 | static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, |
3954 | const char *buffer) | |
8cdea7c0 | 3955 | { |
628f4235 | 3956 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); |
8c7c6e34 | 3957 | int type, name; |
628f4235 KH |
3958 | unsigned long long val; |
3959 | int ret; | |
3960 | ||
8c7c6e34 KH |
3961 | type = MEMFILE_TYPE(cft->private); |
3962 | name = MEMFILE_ATTR(cft->private); | |
3963 | switch (name) { | |
628f4235 | 3964 | case RES_LIMIT: |
4b3bde4c BS |
3965 | if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ |
3966 | ret = -EINVAL; | |
3967 | break; | |
3968 | } | |
628f4235 KH |
3969 | /* This function does all necessary parse...reuse it */ |
3970 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
8c7c6e34 KH |
3971 | if (ret) |
3972 | break; | |
3973 | if (type == _MEM) | |
628f4235 | 3974 | ret = mem_cgroup_resize_limit(memcg, val); |
8c7c6e34 KH |
3975 | else |
3976 | ret = mem_cgroup_resize_memsw_limit(memcg, val); | |
628f4235 | 3977 | break; |
296c81d8 BS |
3978 | case RES_SOFT_LIMIT: |
3979 | ret = res_counter_memparse_write_strategy(buffer, &val); | |
3980 | if (ret) | |
3981 | break; | |
3982 | /* | |
3983 | * For memsw, soft limits are hard to implement in terms | |
3984 | * of semantics, for now, we support soft limits for | |
3985 | * control without swap | |
3986 | */ | |
3987 | if (type == _MEM) | |
3988 | ret = res_counter_set_soft_limit(&memcg->res, val); | |
3989 | else | |
3990 | ret = -EINVAL; | |
3991 | break; | |
628f4235 KH |
3992 | default: |
3993 | ret = -EINVAL; /* should be BUG() ? */ | |
3994 | break; | |
3995 | } | |
3996 | return ret; | |
8cdea7c0 BS |
3997 | } |
3998 | ||
fee7b548 KH |
3999 | static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, |
4000 | unsigned long long *mem_limit, unsigned long long *memsw_limit) | |
4001 | { | |
4002 | struct cgroup *cgroup; | |
4003 | unsigned long long min_limit, min_memsw_limit, tmp; | |
4004 | ||
4005 | min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
4006 | min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
4007 | cgroup = memcg->css.cgroup; | |
4008 | if (!memcg->use_hierarchy) | |
4009 | goto out; | |
4010 | ||
4011 | while (cgroup->parent) { | |
4012 | cgroup = cgroup->parent; | |
4013 | memcg = mem_cgroup_from_cont(cgroup); | |
4014 | if (!memcg->use_hierarchy) | |
4015 | break; | |
4016 | tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); | |
4017 | min_limit = min(min_limit, tmp); | |
4018 | tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); | |
4019 | min_memsw_limit = min(min_memsw_limit, tmp); | |
4020 | } | |
4021 | out: | |
4022 | *mem_limit = min_limit; | |
4023 | *memsw_limit = min_memsw_limit; | |
4024 | return; | |
4025 | } | |
4026 | ||
29f2a4da | 4027 | static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) |
c84872e1 PE |
4028 | { |
4029 | struct mem_cgroup *mem; | |
8c7c6e34 | 4030 | int type, name; |
c84872e1 PE |
4031 | |
4032 | mem = mem_cgroup_from_cont(cont); | |
8c7c6e34 KH |
4033 | type = MEMFILE_TYPE(event); |
4034 | name = MEMFILE_ATTR(event); | |
4035 | switch (name) { | |
29f2a4da | 4036 | case RES_MAX_USAGE: |
8c7c6e34 KH |
4037 | if (type == _MEM) |
4038 | res_counter_reset_max(&mem->res); | |
4039 | else | |
4040 | res_counter_reset_max(&mem->memsw); | |
29f2a4da PE |
4041 | break; |
4042 | case RES_FAILCNT: | |
8c7c6e34 KH |
4043 | if (type == _MEM) |
4044 | res_counter_reset_failcnt(&mem->res); | |
4045 | else | |
4046 | res_counter_reset_failcnt(&mem->memsw); | |
29f2a4da PE |
4047 | break; |
4048 | } | |
f64c3f54 | 4049 | |
85cc59db | 4050 | return 0; |
c84872e1 PE |
4051 | } |
4052 | ||
7dc74be0 DN |
4053 | static u64 mem_cgroup_move_charge_read(struct cgroup *cgrp, |
4054 | struct cftype *cft) | |
4055 | { | |
4056 | return mem_cgroup_from_cont(cgrp)->move_charge_at_immigrate; | |
4057 | } | |
4058 | ||
02491447 | 4059 | #ifdef CONFIG_MMU |
7dc74be0 DN |
4060 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, |
4061 | struct cftype *cft, u64 val) | |
4062 | { | |
4063 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4064 | ||
4065 | if (val >= (1 << NR_MOVE_TYPE)) | |
4066 | return -EINVAL; | |
4067 | /* | |
4068 | * We check this value several times in both in can_attach() and | |
4069 | * attach(), so we need cgroup lock to prevent this value from being | |
4070 | * inconsistent. | |
4071 | */ | |
4072 | cgroup_lock(); | |
4073 | mem->move_charge_at_immigrate = val; | |
4074 | cgroup_unlock(); | |
4075 | ||
4076 | return 0; | |
4077 | } | |
02491447 DN |
4078 | #else |
4079 | static int mem_cgroup_move_charge_write(struct cgroup *cgrp, | |
4080 | struct cftype *cft, u64 val) | |
4081 | { | |
4082 | return -ENOSYS; | |
4083 | } | |
4084 | #endif | |
7dc74be0 | 4085 | |
14067bb3 KH |
4086 | |
4087 | /* For read statistics */ | |
4088 | enum { | |
4089 | MCS_CACHE, | |
4090 | MCS_RSS, | |
d8046582 | 4091 | MCS_FILE_MAPPED, |
14067bb3 KH |
4092 | MCS_PGPGIN, |
4093 | MCS_PGPGOUT, | |
1dd3a273 | 4094 | MCS_SWAP, |
456f998e YH |
4095 | MCS_PGFAULT, |
4096 | MCS_PGMAJFAULT, | |
14067bb3 KH |
4097 | MCS_INACTIVE_ANON, |
4098 | MCS_ACTIVE_ANON, | |
4099 | MCS_INACTIVE_FILE, | |
4100 | MCS_ACTIVE_FILE, | |
4101 | MCS_UNEVICTABLE, | |
4102 | NR_MCS_STAT, | |
4103 | }; | |
4104 | ||
4105 | struct mcs_total_stat { | |
4106 | s64 stat[NR_MCS_STAT]; | |
d2ceb9b7 KH |
4107 | }; |
4108 | ||
14067bb3 KH |
4109 | struct { |
4110 | char *local_name; | |
4111 | char *total_name; | |
4112 | } memcg_stat_strings[NR_MCS_STAT] = { | |
4113 | {"cache", "total_cache"}, | |
4114 | {"rss", "total_rss"}, | |
d69b042f | 4115 | {"mapped_file", "total_mapped_file"}, |
14067bb3 KH |
4116 | {"pgpgin", "total_pgpgin"}, |
4117 | {"pgpgout", "total_pgpgout"}, | |
1dd3a273 | 4118 | {"swap", "total_swap"}, |
456f998e YH |
4119 | {"pgfault", "total_pgfault"}, |
4120 | {"pgmajfault", "total_pgmajfault"}, | |
14067bb3 KH |
4121 | {"inactive_anon", "total_inactive_anon"}, |
4122 | {"active_anon", "total_active_anon"}, | |
4123 | {"inactive_file", "total_inactive_file"}, | |
4124 | {"active_file", "total_active_file"}, | |
4125 | {"unevictable", "total_unevictable"} | |
4126 | }; | |
4127 | ||
4128 | ||
7d74b06f KH |
4129 | static void |
4130 | mem_cgroup_get_local_stat(struct mem_cgroup *mem, struct mcs_total_stat *s) | |
14067bb3 | 4131 | { |
14067bb3 KH |
4132 | s64 val; |
4133 | ||
4134 | /* per cpu stat */ | |
c62b1a3b | 4135 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_CACHE); |
14067bb3 | 4136 | s->stat[MCS_CACHE] += val * PAGE_SIZE; |
c62b1a3b | 4137 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_RSS); |
14067bb3 | 4138 | s->stat[MCS_RSS] += val * PAGE_SIZE; |
c62b1a3b | 4139 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_FILE_MAPPED); |
d8046582 | 4140 | s->stat[MCS_FILE_MAPPED] += val * PAGE_SIZE; |
e9f8974f | 4141 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGPGIN); |
14067bb3 | 4142 | s->stat[MCS_PGPGIN] += val; |
e9f8974f | 4143 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGPGOUT); |
14067bb3 | 4144 | s->stat[MCS_PGPGOUT] += val; |
1dd3a273 | 4145 | if (do_swap_account) { |
c62b1a3b | 4146 | val = mem_cgroup_read_stat(mem, MEM_CGROUP_STAT_SWAPOUT); |
1dd3a273 DN |
4147 | s->stat[MCS_SWAP] += val * PAGE_SIZE; |
4148 | } | |
456f998e YH |
4149 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGFAULT); |
4150 | s->stat[MCS_PGFAULT] += val; | |
4151 | val = mem_cgroup_read_events(mem, MEM_CGROUP_EVENTS_PGMAJFAULT); | |
4152 | s->stat[MCS_PGMAJFAULT] += val; | |
14067bb3 KH |
4153 | |
4154 | /* per zone stat */ | |
4155 | val = mem_cgroup_get_local_zonestat(mem, LRU_INACTIVE_ANON); | |
4156 | s->stat[MCS_INACTIVE_ANON] += val * PAGE_SIZE; | |
4157 | val = mem_cgroup_get_local_zonestat(mem, LRU_ACTIVE_ANON); | |
4158 | s->stat[MCS_ACTIVE_ANON] += val * PAGE_SIZE; | |
4159 | val = mem_cgroup_get_local_zonestat(mem, LRU_INACTIVE_FILE); | |
4160 | s->stat[MCS_INACTIVE_FILE] += val * PAGE_SIZE; | |
4161 | val = mem_cgroup_get_local_zonestat(mem, LRU_ACTIVE_FILE); | |
4162 | s->stat[MCS_ACTIVE_FILE] += val * PAGE_SIZE; | |
4163 | val = mem_cgroup_get_local_zonestat(mem, LRU_UNEVICTABLE); | |
4164 | s->stat[MCS_UNEVICTABLE] += val * PAGE_SIZE; | |
14067bb3 KH |
4165 | } |
4166 | ||
4167 | static void | |
4168 | mem_cgroup_get_total_stat(struct mem_cgroup *mem, struct mcs_total_stat *s) | |
4169 | { | |
7d74b06f KH |
4170 | struct mem_cgroup *iter; |
4171 | ||
4172 | for_each_mem_cgroup_tree(iter, mem) | |
4173 | mem_cgroup_get_local_stat(iter, s); | |
14067bb3 KH |
4174 | } |
4175 | ||
406eb0c9 YH |
4176 | #ifdef CONFIG_NUMA |
4177 | static int mem_control_numa_stat_show(struct seq_file *m, void *arg) | |
4178 | { | |
4179 | int nid; | |
4180 | unsigned long total_nr, file_nr, anon_nr, unevictable_nr; | |
4181 | unsigned long node_nr; | |
4182 | struct cgroup *cont = m->private; | |
4183 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); | |
4184 | ||
4185 | total_nr = mem_cgroup_nr_lru_pages(mem_cont); | |
4186 | seq_printf(m, "total=%lu", total_nr); | |
4187 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
4188 | node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid); | |
4189 | seq_printf(m, " N%d=%lu", nid, node_nr); | |
4190 | } | |
4191 | seq_putc(m, '\n'); | |
4192 | ||
4193 | file_nr = mem_cgroup_nr_file_lru_pages(mem_cont); | |
4194 | seq_printf(m, "file=%lu", file_nr); | |
4195 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
4196 | node_nr = mem_cgroup_node_nr_file_lru_pages(mem_cont, nid); | |
4197 | seq_printf(m, " N%d=%lu", nid, node_nr); | |
4198 | } | |
4199 | seq_putc(m, '\n'); | |
4200 | ||
4201 | anon_nr = mem_cgroup_nr_anon_lru_pages(mem_cont); | |
4202 | seq_printf(m, "anon=%lu", anon_nr); | |
4203 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
4204 | node_nr = mem_cgroup_node_nr_anon_lru_pages(mem_cont, nid); | |
4205 | seq_printf(m, " N%d=%lu", nid, node_nr); | |
4206 | } | |
4207 | seq_putc(m, '\n'); | |
4208 | ||
4209 | unevictable_nr = mem_cgroup_nr_unevictable_lru_pages(mem_cont); | |
4210 | seq_printf(m, "unevictable=%lu", unevictable_nr); | |
4211 | for_each_node_state(nid, N_HIGH_MEMORY) { | |
4212 | node_nr = mem_cgroup_node_nr_unevictable_lru_pages(mem_cont, | |
4213 | nid); | |
4214 | seq_printf(m, " N%d=%lu", nid, node_nr); | |
4215 | } | |
4216 | seq_putc(m, '\n'); | |
4217 | return 0; | |
4218 | } | |
4219 | #endif /* CONFIG_NUMA */ | |
4220 | ||
c64745cf PM |
4221 | static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, |
4222 | struct cgroup_map_cb *cb) | |
d2ceb9b7 | 4223 | { |
d2ceb9b7 | 4224 | struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); |
14067bb3 | 4225 | struct mcs_total_stat mystat; |
d2ceb9b7 KH |
4226 | int i; |
4227 | ||
14067bb3 KH |
4228 | memset(&mystat, 0, sizeof(mystat)); |
4229 | mem_cgroup_get_local_stat(mem_cont, &mystat); | |
d2ceb9b7 | 4230 | |
406eb0c9 | 4231 | |
1dd3a273 DN |
4232 | for (i = 0; i < NR_MCS_STAT; i++) { |
4233 | if (i == MCS_SWAP && !do_swap_account) | |
4234 | continue; | |
14067bb3 | 4235 | cb->fill(cb, memcg_stat_strings[i].local_name, mystat.stat[i]); |
1dd3a273 | 4236 | } |
7b854121 | 4237 | |
14067bb3 | 4238 | /* Hierarchical information */ |
fee7b548 KH |
4239 | { |
4240 | unsigned long long limit, memsw_limit; | |
4241 | memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit); | |
4242 | cb->fill(cb, "hierarchical_memory_limit", limit); | |
4243 | if (do_swap_account) | |
4244 | cb->fill(cb, "hierarchical_memsw_limit", memsw_limit); | |
4245 | } | |
7f016ee8 | 4246 | |
14067bb3 KH |
4247 | memset(&mystat, 0, sizeof(mystat)); |
4248 | mem_cgroup_get_total_stat(mem_cont, &mystat); | |
1dd3a273 DN |
4249 | for (i = 0; i < NR_MCS_STAT; i++) { |
4250 | if (i == MCS_SWAP && !do_swap_account) | |
4251 | continue; | |
14067bb3 | 4252 | cb->fill(cb, memcg_stat_strings[i].total_name, mystat.stat[i]); |
1dd3a273 | 4253 | } |
14067bb3 | 4254 | |
7f016ee8 | 4255 | #ifdef CONFIG_DEBUG_VM |
c772be93 | 4256 | cb->fill(cb, "inactive_ratio", calc_inactive_ratio(mem_cont, NULL)); |
7f016ee8 KM |
4257 | |
4258 | { | |
4259 | int nid, zid; | |
4260 | struct mem_cgroup_per_zone *mz; | |
4261 | unsigned long recent_rotated[2] = {0, 0}; | |
4262 | unsigned long recent_scanned[2] = {0, 0}; | |
4263 | ||
4264 | for_each_online_node(nid) | |
4265 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { | |
4266 | mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); | |
4267 | ||
4268 | recent_rotated[0] += | |
4269 | mz->reclaim_stat.recent_rotated[0]; | |
4270 | recent_rotated[1] += | |
4271 | mz->reclaim_stat.recent_rotated[1]; | |
4272 | recent_scanned[0] += | |
4273 | mz->reclaim_stat.recent_scanned[0]; | |
4274 | recent_scanned[1] += | |
4275 | mz->reclaim_stat.recent_scanned[1]; | |
4276 | } | |
4277 | cb->fill(cb, "recent_rotated_anon", recent_rotated[0]); | |
4278 | cb->fill(cb, "recent_rotated_file", recent_rotated[1]); | |
4279 | cb->fill(cb, "recent_scanned_anon", recent_scanned[0]); | |
4280 | cb->fill(cb, "recent_scanned_file", recent_scanned[1]); | |
4281 | } | |
4282 | #endif | |
4283 | ||
d2ceb9b7 KH |
4284 | return 0; |
4285 | } | |
4286 | ||
a7885eb8 KM |
4287 | static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft) |
4288 | { | |
4289 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4290 | ||
4291 | return get_swappiness(memcg); | |
4292 | } | |
4293 | ||
4294 | static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, | |
4295 | u64 val) | |
4296 | { | |
4297 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4298 | struct mem_cgroup *parent; | |
068b38c1 | 4299 | |
a7885eb8 KM |
4300 | if (val > 100) |
4301 | return -EINVAL; | |
4302 | ||
4303 | if (cgrp->parent == NULL) | |
4304 | return -EINVAL; | |
4305 | ||
4306 | parent = mem_cgroup_from_cont(cgrp->parent); | |
068b38c1 LZ |
4307 | |
4308 | cgroup_lock(); | |
4309 | ||
a7885eb8 KM |
4310 | /* If under hierarchy, only empty-root can set this value */ |
4311 | if ((parent->use_hierarchy) || | |
068b38c1 LZ |
4312 | (memcg->use_hierarchy && !list_empty(&cgrp->children))) { |
4313 | cgroup_unlock(); | |
a7885eb8 | 4314 | return -EINVAL; |
068b38c1 | 4315 | } |
a7885eb8 | 4316 | |
a7885eb8 | 4317 | memcg->swappiness = val; |
a7885eb8 | 4318 | |
068b38c1 LZ |
4319 | cgroup_unlock(); |
4320 | ||
a7885eb8 KM |
4321 | return 0; |
4322 | } | |
4323 | ||
2e72b634 KS |
4324 | static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) |
4325 | { | |
4326 | struct mem_cgroup_threshold_ary *t; | |
4327 | u64 usage; | |
4328 | int i; | |
4329 | ||
4330 | rcu_read_lock(); | |
4331 | if (!swap) | |
2c488db2 | 4332 | t = rcu_dereference(memcg->thresholds.primary); |
2e72b634 | 4333 | else |
2c488db2 | 4334 | t = rcu_dereference(memcg->memsw_thresholds.primary); |
2e72b634 KS |
4335 | |
4336 | if (!t) | |
4337 | goto unlock; | |
4338 | ||
4339 | usage = mem_cgroup_usage(memcg, swap); | |
4340 | ||
4341 | /* | |
4342 | * current_threshold points to threshold just below usage. | |
4343 | * If it's not true, a threshold was crossed after last | |
4344 | * call of __mem_cgroup_threshold(). | |
4345 | */ | |
5407a562 | 4346 | i = t->current_threshold; |
2e72b634 KS |
4347 | |
4348 | /* | |
4349 | * Iterate backward over array of thresholds starting from | |
4350 | * current_threshold and check if a threshold is crossed. | |
4351 | * If none of thresholds below usage is crossed, we read | |
4352 | * only one element of the array here. | |
4353 | */ | |
4354 | for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) | |
4355 | eventfd_signal(t->entries[i].eventfd, 1); | |
4356 | ||
4357 | /* i = current_threshold + 1 */ | |
4358 | i++; | |
4359 | ||
4360 | /* | |
4361 | * Iterate forward over array of thresholds starting from | |
4362 | * current_threshold+1 and check if a threshold is crossed. | |
4363 | * If none of thresholds above usage is crossed, we read | |
4364 | * only one element of the array here. | |
4365 | */ | |
4366 | for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) | |
4367 | eventfd_signal(t->entries[i].eventfd, 1); | |
4368 | ||
4369 | /* Update current_threshold */ | |
5407a562 | 4370 | t->current_threshold = i - 1; |
2e72b634 KS |
4371 | unlock: |
4372 | rcu_read_unlock(); | |
4373 | } | |
4374 | ||
4375 | static void mem_cgroup_threshold(struct mem_cgroup *memcg) | |
4376 | { | |
ad4ca5f4 KS |
4377 | while (memcg) { |
4378 | __mem_cgroup_threshold(memcg, false); | |
4379 | if (do_swap_account) | |
4380 | __mem_cgroup_threshold(memcg, true); | |
4381 | ||
4382 | memcg = parent_mem_cgroup(memcg); | |
4383 | } | |
2e72b634 KS |
4384 | } |
4385 | ||
4386 | static int compare_thresholds(const void *a, const void *b) | |
4387 | { | |
4388 | const struct mem_cgroup_threshold *_a = a; | |
4389 | const struct mem_cgroup_threshold *_b = b; | |
4390 | ||
4391 | return _a->threshold - _b->threshold; | |
4392 | } | |
4393 | ||
7d74b06f | 4394 | static int mem_cgroup_oom_notify_cb(struct mem_cgroup *mem) |
9490ff27 KH |
4395 | { |
4396 | struct mem_cgroup_eventfd_list *ev; | |
4397 | ||
4398 | list_for_each_entry(ev, &mem->oom_notify, list) | |
4399 | eventfd_signal(ev->eventfd, 1); | |
4400 | return 0; | |
4401 | } | |
4402 | ||
4403 | static void mem_cgroup_oom_notify(struct mem_cgroup *mem) | |
4404 | { | |
7d74b06f KH |
4405 | struct mem_cgroup *iter; |
4406 | ||
4407 | for_each_mem_cgroup_tree(iter, mem) | |
4408 | mem_cgroup_oom_notify_cb(iter); | |
9490ff27 KH |
4409 | } |
4410 | ||
4411 | static int mem_cgroup_usage_register_event(struct cgroup *cgrp, | |
4412 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
2e72b634 KS |
4413 | { |
4414 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4415 | struct mem_cgroup_thresholds *thresholds; |
4416 | struct mem_cgroup_threshold_ary *new; | |
2e72b634 KS |
4417 | int type = MEMFILE_TYPE(cft->private); |
4418 | u64 threshold, usage; | |
2c488db2 | 4419 | int i, size, ret; |
2e72b634 KS |
4420 | |
4421 | ret = res_counter_memparse_write_strategy(args, &threshold); | |
4422 | if (ret) | |
4423 | return ret; | |
4424 | ||
4425 | mutex_lock(&memcg->thresholds_lock); | |
2c488db2 | 4426 | |
2e72b634 | 4427 | if (type == _MEM) |
2c488db2 | 4428 | thresholds = &memcg->thresholds; |
2e72b634 | 4429 | else if (type == _MEMSWAP) |
2c488db2 | 4430 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4431 | else |
4432 | BUG(); | |
4433 | ||
4434 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4435 | ||
4436 | /* Check if a threshold crossed before adding a new one */ | |
2c488db2 | 4437 | if (thresholds->primary) |
2e72b634 KS |
4438 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); |
4439 | ||
2c488db2 | 4440 | size = thresholds->primary ? thresholds->primary->size + 1 : 1; |
2e72b634 KS |
4441 | |
4442 | /* Allocate memory for new array of thresholds */ | |
2c488db2 | 4443 | new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold), |
2e72b634 | 4444 | GFP_KERNEL); |
2c488db2 | 4445 | if (!new) { |
2e72b634 KS |
4446 | ret = -ENOMEM; |
4447 | goto unlock; | |
4448 | } | |
2c488db2 | 4449 | new->size = size; |
2e72b634 KS |
4450 | |
4451 | /* Copy thresholds (if any) to new array */ | |
2c488db2 KS |
4452 | if (thresholds->primary) { |
4453 | memcpy(new->entries, thresholds->primary->entries, (size - 1) * | |
2e72b634 | 4454 | sizeof(struct mem_cgroup_threshold)); |
2c488db2 KS |
4455 | } |
4456 | ||
2e72b634 | 4457 | /* Add new threshold */ |
2c488db2 KS |
4458 | new->entries[size - 1].eventfd = eventfd; |
4459 | new->entries[size - 1].threshold = threshold; | |
2e72b634 KS |
4460 | |
4461 | /* Sort thresholds. Registering of new threshold isn't time-critical */ | |
2c488db2 | 4462 | sort(new->entries, size, sizeof(struct mem_cgroup_threshold), |
2e72b634 KS |
4463 | compare_thresholds, NULL); |
4464 | ||
4465 | /* Find current threshold */ | |
2c488db2 | 4466 | new->current_threshold = -1; |
2e72b634 | 4467 | for (i = 0; i < size; i++) { |
2c488db2 | 4468 | if (new->entries[i].threshold < usage) { |
2e72b634 | 4469 | /* |
2c488db2 KS |
4470 | * new->current_threshold will not be used until |
4471 | * rcu_assign_pointer(), so it's safe to increment | |
2e72b634 KS |
4472 | * it here. |
4473 | */ | |
2c488db2 | 4474 | ++new->current_threshold; |
2e72b634 KS |
4475 | } |
4476 | } | |
4477 | ||
2c488db2 KS |
4478 | /* Free old spare buffer and save old primary buffer as spare */ |
4479 | kfree(thresholds->spare); | |
4480 | thresholds->spare = thresholds->primary; | |
4481 | ||
4482 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4483 | |
907860ed | 4484 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4485 | synchronize_rcu(); |
4486 | ||
2e72b634 KS |
4487 | unlock: |
4488 | mutex_unlock(&memcg->thresholds_lock); | |
4489 | ||
4490 | return ret; | |
4491 | } | |
4492 | ||
907860ed | 4493 | static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp, |
9490ff27 | 4494 | struct cftype *cft, struct eventfd_ctx *eventfd) |
2e72b634 KS |
4495 | { |
4496 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
2c488db2 KS |
4497 | struct mem_cgroup_thresholds *thresholds; |
4498 | struct mem_cgroup_threshold_ary *new; | |
2e72b634 KS |
4499 | int type = MEMFILE_TYPE(cft->private); |
4500 | u64 usage; | |
2c488db2 | 4501 | int i, j, size; |
2e72b634 KS |
4502 | |
4503 | mutex_lock(&memcg->thresholds_lock); | |
4504 | if (type == _MEM) | |
2c488db2 | 4505 | thresholds = &memcg->thresholds; |
2e72b634 | 4506 | else if (type == _MEMSWAP) |
2c488db2 | 4507 | thresholds = &memcg->memsw_thresholds; |
2e72b634 KS |
4508 | else |
4509 | BUG(); | |
4510 | ||
4511 | /* | |
4512 | * Something went wrong if we trying to unregister a threshold | |
4513 | * if we don't have thresholds | |
4514 | */ | |
4515 | BUG_ON(!thresholds); | |
4516 | ||
4517 | usage = mem_cgroup_usage(memcg, type == _MEMSWAP); | |
4518 | ||
4519 | /* Check if a threshold crossed before removing */ | |
4520 | __mem_cgroup_threshold(memcg, type == _MEMSWAP); | |
4521 | ||
4522 | /* Calculate new number of threshold */ | |
2c488db2 KS |
4523 | size = 0; |
4524 | for (i = 0; i < thresholds->primary->size; i++) { | |
4525 | if (thresholds->primary->entries[i].eventfd != eventfd) | |
2e72b634 KS |
4526 | size++; |
4527 | } | |
4528 | ||
2c488db2 | 4529 | new = thresholds->spare; |
907860ed | 4530 | |
2e72b634 KS |
4531 | /* Set thresholds array to NULL if we don't have thresholds */ |
4532 | if (!size) { | |
2c488db2 KS |
4533 | kfree(new); |
4534 | new = NULL; | |
907860ed | 4535 | goto swap_buffers; |
2e72b634 KS |
4536 | } |
4537 | ||
2c488db2 | 4538 | new->size = size; |
2e72b634 KS |
4539 | |
4540 | /* Copy thresholds and find current threshold */ | |
2c488db2 KS |
4541 | new->current_threshold = -1; |
4542 | for (i = 0, j = 0; i < thresholds->primary->size; i++) { | |
4543 | if (thresholds->primary->entries[i].eventfd == eventfd) | |
2e72b634 KS |
4544 | continue; |
4545 | ||
2c488db2 KS |
4546 | new->entries[j] = thresholds->primary->entries[i]; |
4547 | if (new->entries[j].threshold < usage) { | |
2e72b634 | 4548 | /* |
2c488db2 | 4549 | * new->current_threshold will not be used |
2e72b634 KS |
4550 | * until rcu_assign_pointer(), so it's safe to increment |
4551 | * it here. | |
4552 | */ | |
2c488db2 | 4553 | ++new->current_threshold; |
2e72b634 KS |
4554 | } |
4555 | j++; | |
4556 | } | |
4557 | ||
907860ed | 4558 | swap_buffers: |
2c488db2 KS |
4559 | /* Swap primary and spare array */ |
4560 | thresholds->spare = thresholds->primary; | |
4561 | rcu_assign_pointer(thresholds->primary, new); | |
2e72b634 | 4562 | |
907860ed | 4563 | /* To be sure that nobody uses thresholds */ |
2e72b634 KS |
4564 | synchronize_rcu(); |
4565 | ||
2e72b634 | 4566 | mutex_unlock(&memcg->thresholds_lock); |
2e72b634 | 4567 | } |
c1e862c1 | 4568 | |
9490ff27 KH |
4569 | static int mem_cgroup_oom_register_event(struct cgroup *cgrp, |
4570 | struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) | |
4571 | { | |
4572 | struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); | |
4573 | struct mem_cgroup_eventfd_list *event; | |
4574 | int type = MEMFILE_TYPE(cft->private); | |
4575 | ||
4576 | BUG_ON(type != _OOM_TYPE); | |
4577 | event = kmalloc(sizeof(*event), GFP_KERNEL); | |
4578 | if (!event) | |
4579 | return -ENOMEM; | |
4580 | ||
4581 | mutex_lock(&memcg_oom_mutex); | |
4582 | ||
4583 | event->eventfd = eventfd; | |
4584 | list_add(&event->list, &memcg->oom_notify); | |
4585 | ||
4586 | /* already in OOM ? */ | |
4587 | if (atomic_read(&memcg->oom_lock)) | |
4588 | eventfd_signal(eventfd, 1); | |
4589 | mutex_unlock(&memcg_oom_mutex); | |
4590 | ||
4591 | return 0; | |
4592 | } | |
4593 | ||
907860ed | 4594 | static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp, |
9490ff27 KH |
4595 | struct cftype *cft, struct eventfd_ctx *eventfd) |
4596 | { | |
4597 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4598 | struct mem_cgroup_eventfd_list *ev, *tmp; | |
4599 | int type = MEMFILE_TYPE(cft->private); | |
4600 | ||
4601 | BUG_ON(type != _OOM_TYPE); | |
4602 | ||
4603 | mutex_lock(&memcg_oom_mutex); | |
4604 | ||
4605 | list_for_each_entry_safe(ev, tmp, &mem->oom_notify, list) { | |
4606 | if (ev->eventfd == eventfd) { | |
4607 | list_del(&ev->list); | |
4608 | kfree(ev); | |
4609 | } | |
4610 | } | |
4611 | ||
4612 | mutex_unlock(&memcg_oom_mutex); | |
9490ff27 KH |
4613 | } |
4614 | ||
3c11ecf4 KH |
4615 | static int mem_cgroup_oom_control_read(struct cgroup *cgrp, |
4616 | struct cftype *cft, struct cgroup_map_cb *cb) | |
4617 | { | |
4618 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4619 | ||
4620 | cb->fill(cb, "oom_kill_disable", mem->oom_kill_disable); | |
4621 | ||
4622 | if (atomic_read(&mem->oom_lock)) | |
4623 | cb->fill(cb, "under_oom", 1); | |
4624 | else | |
4625 | cb->fill(cb, "under_oom", 0); | |
4626 | return 0; | |
4627 | } | |
4628 | ||
3c11ecf4 KH |
4629 | static int mem_cgroup_oom_control_write(struct cgroup *cgrp, |
4630 | struct cftype *cft, u64 val) | |
4631 | { | |
4632 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); | |
4633 | struct mem_cgroup *parent; | |
4634 | ||
4635 | /* cannot set to root cgroup and only 0 and 1 are allowed */ | |
4636 | if (!cgrp->parent || !((val == 0) || (val == 1))) | |
4637 | return -EINVAL; | |
4638 | ||
4639 | parent = mem_cgroup_from_cont(cgrp->parent); | |
4640 | ||
4641 | cgroup_lock(); | |
4642 | /* oom-kill-disable is a flag for subhierarchy. */ | |
4643 | if ((parent->use_hierarchy) || | |
4644 | (mem->use_hierarchy && !list_empty(&cgrp->children))) { | |
4645 | cgroup_unlock(); | |
4646 | return -EINVAL; | |
4647 | } | |
4648 | mem->oom_kill_disable = val; | |
4d845ebf KH |
4649 | if (!val) |
4650 | memcg_oom_recover(mem); | |
3c11ecf4 KH |
4651 | cgroup_unlock(); |
4652 | return 0; | |
4653 | } | |
4654 | ||
406eb0c9 YH |
4655 | #ifdef CONFIG_NUMA |
4656 | static const struct file_operations mem_control_numa_stat_file_operations = { | |
4657 | .read = seq_read, | |
4658 | .llseek = seq_lseek, | |
4659 | .release = single_release, | |
4660 | }; | |
4661 | ||
4662 | static int mem_control_numa_stat_open(struct inode *unused, struct file *file) | |
4663 | { | |
4664 | struct cgroup *cont = file->f_dentry->d_parent->d_fsdata; | |
4665 | ||
4666 | file->f_op = &mem_control_numa_stat_file_operations; | |
4667 | return single_open(file, mem_control_numa_stat_show, cont); | |
4668 | } | |
4669 | #endif /* CONFIG_NUMA */ | |
4670 | ||
8cdea7c0 BS |
4671 | static struct cftype mem_cgroup_files[] = { |
4672 | { | |
0eea1030 | 4673 | .name = "usage_in_bytes", |
8c7c6e34 | 4674 | .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), |
2c3daa72 | 4675 | .read_u64 = mem_cgroup_read, |
9490ff27 KH |
4676 | .register_event = mem_cgroup_usage_register_event, |
4677 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8cdea7c0 | 4678 | }, |
c84872e1 PE |
4679 | { |
4680 | .name = "max_usage_in_bytes", | |
8c7c6e34 | 4681 | .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), |
29f2a4da | 4682 | .trigger = mem_cgroup_reset, |
c84872e1 PE |
4683 | .read_u64 = mem_cgroup_read, |
4684 | }, | |
8cdea7c0 | 4685 | { |
0eea1030 | 4686 | .name = "limit_in_bytes", |
8c7c6e34 | 4687 | .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), |
856c13aa | 4688 | .write_string = mem_cgroup_write, |
2c3daa72 | 4689 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 4690 | }, |
296c81d8 BS |
4691 | { |
4692 | .name = "soft_limit_in_bytes", | |
4693 | .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), | |
4694 | .write_string = mem_cgroup_write, | |
4695 | .read_u64 = mem_cgroup_read, | |
4696 | }, | |
8cdea7c0 BS |
4697 | { |
4698 | .name = "failcnt", | |
8c7c6e34 | 4699 | .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), |
29f2a4da | 4700 | .trigger = mem_cgroup_reset, |
2c3daa72 | 4701 | .read_u64 = mem_cgroup_read, |
8cdea7c0 | 4702 | }, |
d2ceb9b7 KH |
4703 | { |
4704 | .name = "stat", | |
c64745cf | 4705 | .read_map = mem_control_stat_show, |
d2ceb9b7 | 4706 | }, |
c1e862c1 KH |
4707 | { |
4708 | .name = "force_empty", | |
4709 | .trigger = mem_cgroup_force_empty_write, | |
4710 | }, | |
18f59ea7 BS |
4711 | { |
4712 | .name = "use_hierarchy", | |
4713 | .write_u64 = mem_cgroup_hierarchy_write, | |
4714 | .read_u64 = mem_cgroup_hierarchy_read, | |
4715 | }, | |
a7885eb8 KM |
4716 | { |
4717 | .name = "swappiness", | |
4718 | .read_u64 = mem_cgroup_swappiness_read, | |
4719 | .write_u64 = mem_cgroup_swappiness_write, | |
4720 | }, | |
7dc74be0 DN |
4721 | { |
4722 | .name = "move_charge_at_immigrate", | |
4723 | .read_u64 = mem_cgroup_move_charge_read, | |
4724 | .write_u64 = mem_cgroup_move_charge_write, | |
4725 | }, | |
9490ff27 KH |
4726 | { |
4727 | .name = "oom_control", | |
3c11ecf4 KH |
4728 | .read_map = mem_cgroup_oom_control_read, |
4729 | .write_u64 = mem_cgroup_oom_control_write, | |
9490ff27 KH |
4730 | .register_event = mem_cgroup_oom_register_event, |
4731 | .unregister_event = mem_cgroup_oom_unregister_event, | |
4732 | .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), | |
4733 | }, | |
406eb0c9 YH |
4734 | #ifdef CONFIG_NUMA |
4735 | { | |
4736 | .name = "numa_stat", | |
4737 | .open = mem_control_numa_stat_open, | |
89577127 | 4738 | .mode = S_IRUGO, |
406eb0c9 YH |
4739 | }, |
4740 | #endif | |
8cdea7c0 BS |
4741 | }; |
4742 | ||
8c7c6e34 KH |
4743 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4744 | static struct cftype memsw_cgroup_files[] = { | |
4745 | { | |
4746 | .name = "memsw.usage_in_bytes", | |
4747 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), | |
4748 | .read_u64 = mem_cgroup_read, | |
9490ff27 KH |
4749 | .register_event = mem_cgroup_usage_register_event, |
4750 | .unregister_event = mem_cgroup_usage_unregister_event, | |
8c7c6e34 KH |
4751 | }, |
4752 | { | |
4753 | .name = "memsw.max_usage_in_bytes", | |
4754 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), | |
4755 | .trigger = mem_cgroup_reset, | |
4756 | .read_u64 = mem_cgroup_read, | |
4757 | }, | |
4758 | { | |
4759 | .name = "memsw.limit_in_bytes", | |
4760 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), | |
4761 | .write_string = mem_cgroup_write, | |
4762 | .read_u64 = mem_cgroup_read, | |
4763 | }, | |
4764 | { | |
4765 | .name = "memsw.failcnt", | |
4766 | .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), | |
4767 | .trigger = mem_cgroup_reset, | |
4768 | .read_u64 = mem_cgroup_read, | |
4769 | }, | |
4770 | }; | |
4771 | ||
4772 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4773 | { | |
4774 | if (!do_swap_account) | |
4775 | return 0; | |
4776 | return cgroup_add_files(cont, ss, memsw_cgroup_files, | |
4777 | ARRAY_SIZE(memsw_cgroup_files)); | |
4778 | }; | |
4779 | #else | |
4780 | static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) | |
4781 | { | |
4782 | return 0; | |
4783 | } | |
4784 | #endif | |
4785 | ||
6d12e2d8 KH |
4786 | static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
4787 | { | |
4788 | struct mem_cgroup_per_node *pn; | |
1ecaab2b | 4789 | struct mem_cgroup_per_zone *mz; |
b69408e8 | 4790 | enum lru_list l; |
41e3355d | 4791 | int zone, tmp = node; |
1ecaab2b KH |
4792 | /* |
4793 | * This routine is called against possible nodes. | |
4794 | * But it's BUG to call kmalloc() against offline node. | |
4795 | * | |
4796 | * TODO: this routine can waste much memory for nodes which will | |
4797 | * never be onlined. It's better to use memory hotplug callback | |
4798 | * function. | |
4799 | */ | |
41e3355d KH |
4800 | if (!node_state(node, N_NORMAL_MEMORY)) |
4801 | tmp = -1; | |
17295c88 | 4802 | pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); |
6d12e2d8 KH |
4803 | if (!pn) |
4804 | return 1; | |
1ecaab2b | 4805 | |
6d12e2d8 | 4806 | mem->info.nodeinfo[node] = pn; |
1ecaab2b KH |
4807 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { |
4808 | mz = &pn->zoneinfo[zone]; | |
b69408e8 CL |
4809 | for_each_lru(l) |
4810 | INIT_LIST_HEAD(&mz->lists[l]); | |
f64c3f54 | 4811 | mz->usage_in_excess = 0; |
4e416953 BS |
4812 | mz->on_tree = false; |
4813 | mz->mem = mem; | |
1ecaab2b | 4814 | } |
6d12e2d8 KH |
4815 | return 0; |
4816 | } | |
4817 | ||
1ecaab2b KH |
4818 | static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) |
4819 | { | |
4820 | kfree(mem->info.nodeinfo[node]); | |
4821 | } | |
4822 | ||
33327948 KH |
4823 | static struct mem_cgroup *mem_cgroup_alloc(void) |
4824 | { | |
4825 | struct mem_cgroup *mem; | |
c62b1a3b | 4826 | int size = sizeof(struct mem_cgroup); |
33327948 | 4827 | |
c62b1a3b | 4828 | /* Can be very big if MAX_NUMNODES is very big */ |
c8dad2bb | 4829 | if (size < PAGE_SIZE) |
17295c88 | 4830 | mem = kzalloc(size, GFP_KERNEL); |
33327948 | 4831 | else |
17295c88 | 4832 | mem = vzalloc(size); |
33327948 | 4833 | |
e7bbcdf3 DC |
4834 | if (!mem) |
4835 | return NULL; | |
4836 | ||
c62b1a3b | 4837 | mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu); |
d2e61b8d DC |
4838 | if (!mem->stat) |
4839 | goto out_free; | |
711d3d2c | 4840 | spin_lock_init(&mem->pcp_counter_lock); |
33327948 | 4841 | return mem; |
d2e61b8d DC |
4842 | |
4843 | out_free: | |
4844 | if (size < PAGE_SIZE) | |
4845 | kfree(mem); | |
4846 | else | |
4847 | vfree(mem); | |
4848 | return NULL; | |
33327948 KH |
4849 | } |
4850 | ||
8c7c6e34 KH |
4851 | /* |
4852 | * At destroying mem_cgroup, references from swap_cgroup can remain. | |
4853 | * (scanning all at force_empty is too costly...) | |
4854 | * | |
4855 | * Instead of clearing all references at force_empty, we remember | |
4856 | * the number of reference from swap_cgroup and free mem_cgroup when | |
4857 | * it goes down to 0. | |
4858 | * | |
8c7c6e34 KH |
4859 | * Removal of cgroup itself succeeds regardless of refs from swap. |
4860 | */ | |
4861 | ||
a7ba0eef | 4862 | static void __mem_cgroup_free(struct mem_cgroup *mem) |
33327948 | 4863 | { |
08e552c6 KH |
4864 | int node; |
4865 | ||
f64c3f54 | 4866 | mem_cgroup_remove_from_trees(mem); |
04046e1a KH |
4867 | free_css_id(&mem_cgroup_subsys, &mem->css); |
4868 | ||
08e552c6 KH |
4869 | for_each_node_state(node, N_POSSIBLE) |
4870 | free_mem_cgroup_per_zone_info(mem, node); | |
4871 | ||
c62b1a3b KH |
4872 | free_percpu(mem->stat); |
4873 | if (sizeof(struct mem_cgroup) < PAGE_SIZE) | |
33327948 KH |
4874 | kfree(mem); |
4875 | else | |
4876 | vfree(mem); | |
4877 | } | |
4878 | ||
8c7c6e34 KH |
4879 | static void mem_cgroup_get(struct mem_cgroup *mem) |
4880 | { | |
4881 | atomic_inc(&mem->refcnt); | |
4882 | } | |
4883 | ||
483c30b5 | 4884 | static void __mem_cgroup_put(struct mem_cgroup *mem, int count) |
8c7c6e34 | 4885 | { |
483c30b5 | 4886 | if (atomic_sub_and_test(count, &mem->refcnt)) { |
7bcc1bb1 | 4887 | struct mem_cgroup *parent = parent_mem_cgroup(mem); |
a7ba0eef | 4888 | __mem_cgroup_free(mem); |
7bcc1bb1 DN |
4889 | if (parent) |
4890 | mem_cgroup_put(parent); | |
4891 | } | |
8c7c6e34 KH |
4892 | } |
4893 | ||
483c30b5 DN |
4894 | static void mem_cgroup_put(struct mem_cgroup *mem) |
4895 | { | |
4896 | __mem_cgroup_put(mem, 1); | |
4897 | } | |
4898 | ||
7bcc1bb1 DN |
4899 | /* |
4900 | * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. | |
4901 | */ | |
4902 | static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem) | |
4903 | { | |
4904 | if (!mem->res.parent) | |
4905 | return NULL; | |
4906 | return mem_cgroup_from_res_counter(mem->res.parent, res); | |
4907 | } | |
33327948 | 4908 | |
c077719b KH |
4909 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP |
4910 | static void __init enable_swap_cgroup(void) | |
4911 | { | |
f8d66542 | 4912 | if (!mem_cgroup_disabled() && really_do_swap_account) |
c077719b KH |
4913 | do_swap_account = 1; |
4914 | } | |
4915 | #else | |
4916 | static void __init enable_swap_cgroup(void) | |
4917 | { | |
4918 | } | |
4919 | #endif | |
4920 | ||
f64c3f54 BS |
4921 | static int mem_cgroup_soft_limit_tree_init(void) |
4922 | { | |
4923 | struct mem_cgroup_tree_per_node *rtpn; | |
4924 | struct mem_cgroup_tree_per_zone *rtpz; | |
4925 | int tmp, node, zone; | |
4926 | ||
4927 | for_each_node_state(node, N_POSSIBLE) { | |
4928 | tmp = node; | |
4929 | if (!node_state(node, N_NORMAL_MEMORY)) | |
4930 | tmp = -1; | |
4931 | rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, tmp); | |
4932 | if (!rtpn) | |
4933 | return 1; | |
4934 | ||
4935 | soft_limit_tree.rb_tree_per_node[node] = rtpn; | |
4936 | ||
4937 | for (zone = 0; zone < MAX_NR_ZONES; zone++) { | |
4938 | rtpz = &rtpn->rb_tree_per_zone[zone]; | |
4939 | rtpz->rb_root = RB_ROOT; | |
4940 | spin_lock_init(&rtpz->lock); | |
4941 | } | |
4942 | } | |
4943 | return 0; | |
4944 | } | |
4945 | ||
0eb253e2 | 4946 | static struct cgroup_subsys_state * __ref |
8cdea7c0 BS |
4947 | mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) |
4948 | { | |
28dbc4b6 | 4949 | struct mem_cgroup *mem, *parent; |
04046e1a | 4950 | long error = -ENOMEM; |
6d12e2d8 | 4951 | int node; |
8cdea7c0 | 4952 | |
c8dad2bb JB |
4953 | mem = mem_cgroup_alloc(); |
4954 | if (!mem) | |
04046e1a | 4955 | return ERR_PTR(error); |
78fb7466 | 4956 | |
6d12e2d8 KH |
4957 | for_each_node_state(node, N_POSSIBLE) |
4958 | if (alloc_mem_cgroup_per_zone_info(mem, node)) | |
4959 | goto free_out; | |
f64c3f54 | 4960 | |
c077719b | 4961 | /* root ? */ |
28dbc4b6 | 4962 | if (cont->parent == NULL) { |
cdec2e42 | 4963 | int cpu; |
c077719b | 4964 | enable_swap_cgroup(); |
28dbc4b6 | 4965 | parent = NULL; |
4b3bde4c | 4966 | root_mem_cgroup = mem; |
f64c3f54 BS |
4967 | if (mem_cgroup_soft_limit_tree_init()) |
4968 | goto free_out; | |
cdec2e42 KH |
4969 | for_each_possible_cpu(cpu) { |
4970 | struct memcg_stock_pcp *stock = | |
4971 | &per_cpu(memcg_stock, cpu); | |
4972 | INIT_WORK(&stock->work, drain_local_stock); | |
4973 | } | |
711d3d2c | 4974 | hotcpu_notifier(memcg_cpu_hotplug_callback, 0); |
18f59ea7 | 4975 | } else { |
28dbc4b6 | 4976 | parent = mem_cgroup_from_cont(cont->parent); |
18f59ea7 | 4977 | mem->use_hierarchy = parent->use_hierarchy; |
3c11ecf4 | 4978 | mem->oom_kill_disable = parent->oom_kill_disable; |
18f59ea7 | 4979 | } |
28dbc4b6 | 4980 | |
18f59ea7 BS |
4981 | if (parent && parent->use_hierarchy) { |
4982 | res_counter_init(&mem->res, &parent->res); | |
4983 | res_counter_init(&mem->memsw, &parent->memsw); | |
7bcc1bb1 DN |
4984 | /* |
4985 | * We increment refcnt of the parent to ensure that we can | |
4986 | * safely access it on res_counter_charge/uncharge. | |
4987 | * This refcnt will be decremented when freeing this | |
4988 | * mem_cgroup(see mem_cgroup_put). | |
4989 | */ | |
4990 | mem_cgroup_get(parent); | |
18f59ea7 BS |
4991 | } else { |
4992 | res_counter_init(&mem->res, NULL); | |
4993 | res_counter_init(&mem->memsw, NULL); | |
4994 | } | |
04046e1a | 4995 | mem->last_scanned_child = 0; |
889976db | 4996 | mem->last_scanned_node = MAX_NUMNODES; |
9490ff27 | 4997 | INIT_LIST_HEAD(&mem->oom_notify); |
6d61ef40 | 4998 | |
a7885eb8 KM |
4999 | if (parent) |
5000 | mem->swappiness = get_swappiness(parent); | |
a7ba0eef | 5001 | atomic_set(&mem->refcnt, 1); |
7dc74be0 | 5002 | mem->move_charge_at_immigrate = 0; |
2e72b634 | 5003 | mutex_init(&mem->thresholds_lock); |
8cdea7c0 | 5004 | return &mem->css; |
6d12e2d8 | 5005 | free_out: |
a7ba0eef | 5006 | __mem_cgroup_free(mem); |
4b3bde4c | 5007 | root_mem_cgroup = NULL; |
04046e1a | 5008 | return ERR_PTR(error); |
8cdea7c0 BS |
5009 | } |
5010 | ||
ec64f515 | 5011 | static int mem_cgroup_pre_destroy(struct cgroup_subsys *ss, |
df878fb0 KH |
5012 | struct cgroup *cont) |
5013 | { | |
5014 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); | |
ec64f515 KH |
5015 | |
5016 | return mem_cgroup_force_empty(mem, false); | |
df878fb0 KH |
5017 | } |
5018 | ||
8cdea7c0 BS |
5019 | static void mem_cgroup_destroy(struct cgroup_subsys *ss, |
5020 | struct cgroup *cont) | |
5021 | { | |
c268e994 | 5022 | struct mem_cgroup *mem = mem_cgroup_from_cont(cont); |
c268e994 | 5023 | |
c268e994 | 5024 | mem_cgroup_put(mem); |
8cdea7c0 BS |
5025 | } |
5026 | ||
5027 | static int mem_cgroup_populate(struct cgroup_subsys *ss, | |
5028 | struct cgroup *cont) | |
5029 | { | |
8c7c6e34 KH |
5030 | int ret; |
5031 | ||
5032 | ret = cgroup_add_files(cont, ss, mem_cgroup_files, | |
5033 | ARRAY_SIZE(mem_cgroup_files)); | |
5034 | ||
5035 | if (!ret) | |
5036 | ret = register_memsw_files(cont, ss); | |
5037 | return ret; | |
8cdea7c0 BS |
5038 | } |
5039 | ||
02491447 | 5040 | #ifdef CONFIG_MMU |
7dc74be0 | 5041 | /* Handlers for move charge at task migration. */ |
854ffa8d DN |
5042 | #define PRECHARGE_COUNT_AT_ONCE 256 |
5043 | static int mem_cgroup_do_precharge(unsigned long count) | |
7dc74be0 | 5044 | { |
854ffa8d DN |
5045 | int ret = 0; |
5046 | int batch_count = PRECHARGE_COUNT_AT_ONCE; | |
4ffef5fe DN |
5047 | struct mem_cgroup *mem = mc.to; |
5048 | ||
854ffa8d DN |
5049 | if (mem_cgroup_is_root(mem)) { |
5050 | mc.precharge += count; | |
5051 | /* we don't need css_get for root */ | |
5052 | return ret; | |
5053 | } | |
5054 | /* try to charge at once */ | |
5055 | if (count > 1) { | |
5056 | struct res_counter *dummy; | |
5057 | /* | |
5058 | * "mem" cannot be under rmdir() because we've already checked | |
5059 | * by cgroup_lock_live_cgroup() that it is not removed and we | |
5060 | * are still under the same cgroup_mutex. So we can postpone | |
5061 | * css_get(). | |
5062 | */ | |
5063 | if (res_counter_charge(&mem->res, PAGE_SIZE * count, &dummy)) | |
5064 | goto one_by_one; | |
5065 | if (do_swap_account && res_counter_charge(&mem->memsw, | |
5066 | PAGE_SIZE * count, &dummy)) { | |
5067 | res_counter_uncharge(&mem->res, PAGE_SIZE * count); | |
5068 | goto one_by_one; | |
5069 | } | |
5070 | mc.precharge += count; | |
854ffa8d DN |
5071 | return ret; |
5072 | } | |
5073 | one_by_one: | |
5074 | /* fall back to one by one charge */ | |
5075 | while (count--) { | |
5076 | if (signal_pending(current)) { | |
5077 | ret = -EINTR; | |
5078 | break; | |
5079 | } | |
5080 | if (!batch_count--) { | |
5081 | batch_count = PRECHARGE_COUNT_AT_ONCE; | |
5082 | cond_resched(); | |
5083 | } | |
7ec99d62 | 5084 | ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, 1, &mem, false); |
854ffa8d DN |
5085 | if (ret || !mem) |
5086 | /* mem_cgroup_clear_mc() will do uncharge later */ | |
5087 | return -ENOMEM; | |
5088 | mc.precharge++; | |
5089 | } | |
4ffef5fe DN |
5090 | return ret; |
5091 | } | |
5092 | ||
5093 | /** | |
5094 | * is_target_pte_for_mc - check a pte whether it is valid for move charge | |
5095 | * @vma: the vma the pte to be checked belongs | |
5096 | * @addr: the address corresponding to the pte to be checked | |
5097 | * @ptent: the pte to be checked | |
02491447 | 5098 | * @target: the pointer the target page or swap ent will be stored(can be NULL) |
4ffef5fe DN |
5099 | * |
5100 | * Returns | |
5101 | * 0(MC_TARGET_NONE): if the pte is not a target for move charge. | |
5102 | * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for | |
5103 | * move charge. if @target is not NULL, the page is stored in target->page | |
5104 | * with extra refcnt got(Callers should handle it). | |
02491447 DN |
5105 | * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a |
5106 | * target for charge migration. if @target is not NULL, the entry is stored | |
5107 | * in target->ent. | |
4ffef5fe DN |
5108 | * |
5109 | * Called with pte lock held. | |
5110 | */ | |
4ffef5fe DN |
5111 | union mc_target { |
5112 | struct page *page; | |
02491447 | 5113 | swp_entry_t ent; |
4ffef5fe DN |
5114 | }; |
5115 | ||
4ffef5fe DN |
5116 | enum mc_target_type { |
5117 | MC_TARGET_NONE, /* not used */ | |
5118 | MC_TARGET_PAGE, | |
02491447 | 5119 | MC_TARGET_SWAP, |
4ffef5fe DN |
5120 | }; |
5121 | ||
90254a65 DN |
5122 | static struct page *mc_handle_present_pte(struct vm_area_struct *vma, |
5123 | unsigned long addr, pte_t ptent) | |
4ffef5fe | 5124 | { |
90254a65 | 5125 | struct page *page = vm_normal_page(vma, addr, ptent); |
4ffef5fe | 5126 | |
90254a65 DN |
5127 | if (!page || !page_mapped(page)) |
5128 | return NULL; | |
5129 | if (PageAnon(page)) { | |
5130 | /* we don't move shared anon */ | |
5131 | if (!move_anon() || page_mapcount(page) > 2) | |
5132 | return NULL; | |
87946a72 DN |
5133 | } else if (!move_file()) |
5134 | /* we ignore mapcount for file pages */ | |
90254a65 DN |
5135 | return NULL; |
5136 | if (!get_page_unless_zero(page)) | |
5137 | return NULL; | |
5138 | ||
5139 | return page; | |
5140 | } | |
5141 | ||
5142 | static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, | |
5143 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5144 | { | |
5145 | int usage_count; | |
5146 | struct page *page = NULL; | |
5147 | swp_entry_t ent = pte_to_swp_entry(ptent); | |
5148 | ||
5149 | if (!move_anon() || non_swap_entry(ent)) | |
5150 | return NULL; | |
5151 | usage_count = mem_cgroup_count_swap_user(ent, &page); | |
5152 | if (usage_count > 1) { /* we don't move shared anon */ | |
02491447 DN |
5153 | if (page) |
5154 | put_page(page); | |
90254a65 | 5155 | return NULL; |
02491447 | 5156 | } |
90254a65 DN |
5157 | if (do_swap_account) |
5158 | entry->val = ent.val; | |
5159 | ||
5160 | return page; | |
5161 | } | |
5162 | ||
87946a72 DN |
5163 | static struct page *mc_handle_file_pte(struct vm_area_struct *vma, |
5164 | unsigned long addr, pte_t ptent, swp_entry_t *entry) | |
5165 | { | |
5166 | struct page *page = NULL; | |
5167 | struct inode *inode; | |
5168 | struct address_space *mapping; | |
5169 | pgoff_t pgoff; | |
5170 | ||
5171 | if (!vma->vm_file) /* anonymous vma */ | |
5172 | return NULL; | |
5173 | if (!move_file()) | |
5174 | return NULL; | |
5175 | ||
5176 | inode = vma->vm_file->f_path.dentry->d_inode; | |
5177 | mapping = vma->vm_file->f_mapping; | |
5178 | if (pte_none(ptent)) | |
5179 | pgoff = linear_page_index(vma, addr); | |
5180 | else /* pte_file(ptent) is true */ | |
5181 | pgoff = pte_to_pgoff(ptent); | |
5182 | ||
5183 | /* page is moved even if it's not RSS of this task(page-faulted). */ | |
5184 | if (!mapping_cap_swap_backed(mapping)) { /* normal file */ | |
5185 | page = find_get_page(mapping, pgoff); | |
5186 | } else { /* shmem/tmpfs file. we should take account of swap too. */ | |
5187 | swp_entry_t ent; | |
5188 | mem_cgroup_get_shmem_target(inode, pgoff, &page, &ent); | |
5189 | if (do_swap_account) | |
5190 | entry->val = ent.val; | |
5191 | } | |
5192 | ||
5193 | return page; | |
5194 | } | |
5195 | ||
90254a65 DN |
5196 | static int is_target_pte_for_mc(struct vm_area_struct *vma, |
5197 | unsigned long addr, pte_t ptent, union mc_target *target) | |
5198 | { | |
5199 | struct page *page = NULL; | |
5200 | struct page_cgroup *pc; | |
5201 | int ret = 0; | |
5202 | swp_entry_t ent = { .val = 0 }; | |
5203 | ||
5204 | if (pte_present(ptent)) | |
5205 | page = mc_handle_present_pte(vma, addr, ptent); | |
5206 | else if (is_swap_pte(ptent)) | |
5207 | page = mc_handle_swap_pte(vma, addr, ptent, &ent); | |
87946a72 DN |
5208 | else if (pte_none(ptent) || pte_file(ptent)) |
5209 | page = mc_handle_file_pte(vma, addr, ptent, &ent); | |
90254a65 DN |
5210 | |
5211 | if (!page && !ent.val) | |
5212 | return 0; | |
02491447 DN |
5213 | if (page) { |
5214 | pc = lookup_page_cgroup(page); | |
5215 | /* | |
5216 | * Do only loose check w/o page_cgroup lock. | |
5217 | * mem_cgroup_move_account() checks the pc is valid or not under | |
5218 | * the lock. | |
5219 | */ | |
5220 | if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { | |
5221 | ret = MC_TARGET_PAGE; | |
5222 | if (target) | |
5223 | target->page = page; | |
5224 | } | |
5225 | if (!ret || !target) | |
5226 | put_page(page); | |
5227 | } | |
90254a65 DN |
5228 | /* There is a swap entry and a page doesn't exist or isn't charged */ |
5229 | if (ent.val && !ret && | |
7f0f1546 KH |
5230 | css_id(&mc.from->css) == lookup_swap_cgroup(ent)) { |
5231 | ret = MC_TARGET_SWAP; | |
5232 | if (target) | |
5233 | target->ent = ent; | |
4ffef5fe | 5234 | } |
4ffef5fe DN |
5235 | return ret; |
5236 | } | |
5237 | ||
5238 | static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, | |
5239 | unsigned long addr, unsigned long end, | |
5240 | struct mm_walk *walk) | |
5241 | { | |
5242 | struct vm_area_struct *vma = walk->private; | |
5243 | pte_t *pte; | |
5244 | spinlock_t *ptl; | |
5245 | ||
03319327 DH |
5246 | split_huge_page_pmd(walk->mm, pmd); |
5247 | ||
4ffef5fe DN |
5248 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
5249 | for (; addr != end; pte++, addr += PAGE_SIZE) | |
5250 | if (is_target_pte_for_mc(vma, addr, *pte, NULL)) | |
5251 | mc.precharge++; /* increment precharge temporarily */ | |
5252 | pte_unmap_unlock(pte - 1, ptl); | |
5253 | cond_resched(); | |
5254 | ||
7dc74be0 DN |
5255 | return 0; |
5256 | } | |
5257 | ||
4ffef5fe DN |
5258 | static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) |
5259 | { | |
5260 | unsigned long precharge; | |
5261 | struct vm_area_struct *vma; | |
5262 | ||
dfe076b0 | 5263 | down_read(&mm->mmap_sem); |
4ffef5fe DN |
5264 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5265 | struct mm_walk mem_cgroup_count_precharge_walk = { | |
5266 | .pmd_entry = mem_cgroup_count_precharge_pte_range, | |
5267 | .mm = mm, | |
5268 | .private = vma, | |
5269 | }; | |
5270 | if (is_vm_hugetlb_page(vma)) | |
5271 | continue; | |
4ffef5fe DN |
5272 | walk_page_range(vma->vm_start, vma->vm_end, |
5273 | &mem_cgroup_count_precharge_walk); | |
5274 | } | |
dfe076b0 | 5275 | up_read(&mm->mmap_sem); |
4ffef5fe DN |
5276 | |
5277 | precharge = mc.precharge; | |
5278 | mc.precharge = 0; | |
5279 | ||
5280 | return precharge; | |
5281 | } | |
5282 | ||
4ffef5fe DN |
5283 | static int mem_cgroup_precharge_mc(struct mm_struct *mm) |
5284 | { | |
dfe076b0 DN |
5285 | unsigned long precharge = mem_cgroup_count_precharge(mm); |
5286 | ||
5287 | VM_BUG_ON(mc.moving_task); | |
5288 | mc.moving_task = current; | |
5289 | return mem_cgroup_do_precharge(precharge); | |
4ffef5fe DN |
5290 | } |
5291 | ||
dfe076b0 DN |
5292 | /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ |
5293 | static void __mem_cgroup_clear_mc(void) | |
4ffef5fe | 5294 | { |
2bd9bb20 KH |
5295 | struct mem_cgroup *from = mc.from; |
5296 | struct mem_cgroup *to = mc.to; | |
5297 | ||
4ffef5fe | 5298 | /* we must uncharge all the leftover precharges from mc.to */ |
854ffa8d DN |
5299 | if (mc.precharge) { |
5300 | __mem_cgroup_cancel_charge(mc.to, mc.precharge); | |
5301 | mc.precharge = 0; | |
5302 | } | |
5303 | /* | |
5304 | * we didn't uncharge from mc.from at mem_cgroup_move_account(), so | |
5305 | * we must uncharge here. | |
5306 | */ | |
5307 | if (mc.moved_charge) { | |
5308 | __mem_cgroup_cancel_charge(mc.from, mc.moved_charge); | |
5309 | mc.moved_charge = 0; | |
4ffef5fe | 5310 | } |
483c30b5 DN |
5311 | /* we must fixup refcnts and charges */ |
5312 | if (mc.moved_swap) { | |
483c30b5 DN |
5313 | /* uncharge swap account from the old cgroup */ |
5314 | if (!mem_cgroup_is_root(mc.from)) | |
5315 | res_counter_uncharge(&mc.from->memsw, | |
5316 | PAGE_SIZE * mc.moved_swap); | |
5317 | __mem_cgroup_put(mc.from, mc.moved_swap); | |
5318 | ||
5319 | if (!mem_cgroup_is_root(mc.to)) { | |
5320 | /* | |
5321 | * we charged both to->res and to->memsw, so we should | |
5322 | * uncharge to->res. | |
5323 | */ | |
5324 | res_counter_uncharge(&mc.to->res, | |
5325 | PAGE_SIZE * mc.moved_swap); | |
483c30b5 DN |
5326 | } |
5327 | /* we've already done mem_cgroup_get(mc.to) */ | |
483c30b5 DN |
5328 | mc.moved_swap = 0; |
5329 | } | |
dfe076b0 DN |
5330 | memcg_oom_recover(from); |
5331 | memcg_oom_recover(to); | |
5332 | wake_up_all(&mc.waitq); | |
5333 | } | |
5334 | ||
5335 | static void mem_cgroup_clear_mc(void) | |
5336 | { | |
5337 | struct mem_cgroup *from = mc.from; | |
5338 | ||
5339 | /* | |
5340 | * we must clear moving_task before waking up waiters at the end of | |
5341 | * task migration. | |
5342 | */ | |
5343 | mc.moving_task = NULL; | |
5344 | __mem_cgroup_clear_mc(); | |
2bd9bb20 | 5345 | spin_lock(&mc.lock); |
4ffef5fe DN |
5346 | mc.from = NULL; |
5347 | mc.to = NULL; | |
2bd9bb20 | 5348 | spin_unlock(&mc.lock); |
32047e2a | 5349 | mem_cgroup_end_move(from); |
4ffef5fe DN |
5350 | } |
5351 | ||
7dc74be0 DN |
5352 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, |
5353 | struct cgroup *cgroup, | |
f780bdb7 | 5354 | struct task_struct *p) |
7dc74be0 DN |
5355 | { |
5356 | int ret = 0; | |
5357 | struct mem_cgroup *mem = mem_cgroup_from_cont(cgroup); | |
5358 | ||
5359 | if (mem->move_charge_at_immigrate) { | |
5360 | struct mm_struct *mm; | |
5361 | struct mem_cgroup *from = mem_cgroup_from_task(p); | |
5362 | ||
5363 | VM_BUG_ON(from == mem); | |
5364 | ||
5365 | mm = get_task_mm(p); | |
5366 | if (!mm) | |
5367 | return 0; | |
7dc74be0 | 5368 | /* We move charges only when we move a owner of the mm */ |
4ffef5fe DN |
5369 | if (mm->owner == p) { |
5370 | VM_BUG_ON(mc.from); | |
5371 | VM_BUG_ON(mc.to); | |
5372 | VM_BUG_ON(mc.precharge); | |
854ffa8d | 5373 | VM_BUG_ON(mc.moved_charge); |
483c30b5 | 5374 | VM_BUG_ON(mc.moved_swap); |
32047e2a | 5375 | mem_cgroup_start_move(from); |
2bd9bb20 | 5376 | spin_lock(&mc.lock); |
4ffef5fe DN |
5377 | mc.from = from; |
5378 | mc.to = mem; | |
2bd9bb20 | 5379 | spin_unlock(&mc.lock); |
dfe076b0 | 5380 | /* We set mc.moving_task later */ |
4ffef5fe DN |
5381 | |
5382 | ret = mem_cgroup_precharge_mc(mm); | |
5383 | if (ret) | |
5384 | mem_cgroup_clear_mc(); | |
dfe076b0 DN |
5385 | } |
5386 | mmput(mm); | |
7dc74be0 DN |
5387 | } |
5388 | return ret; | |
5389 | } | |
5390 | ||
5391 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, | |
5392 | struct cgroup *cgroup, | |
f780bdb7 | 5393 | struct task_struct *p) |
7dc74be0 | 5394 | { |
4ffef5fe | 5395 | mem_cgroup_clear_mc(); |
7dc74be0 DN |
5396 | } |
5397 | ||
4ffef5fe DN |
5398 | static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, |
5399 | unsigned long addr, unsigned long end, | |
5400 | struct mm_walk *walk) | |
7dc74be0 | 5401 | { |
4ffef5fe DN |
5402 | int ret = 0; |
5403 | struct vm_area_struct *vma = walk->private; | |
5404 | pte_t *pte; | |
5405 | spinlock_t *ptl; | |
5406 | ||
03319327 | 5407 | split_huge_page_pmd(walk->mm, pmd); |
4ffef5fe DN |
5408 | retry: |
5409 | pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
5410 | for (; addr != end; addr += PAGE_SIZE) { | |
5411 | pte_t ptent = *(pte++); | |
5412 | union mc_target target; | |
5413 | int type; | |
5414 | struct page *page; | |
5415 | struct page_cgroup *pc; | |
02491447 | 5416 | swp_entry_t ent; |
4ffef5fe DN |
5417 | |
5418 | if (!mc.precharge) | |
5419 | break; | |
5420 | ||
5421 | type = is_target_pte_for_mc(vma, addr, ptent, &target); | |
5422 | switch (type) { | |
5423 | case MC_TARGET_PAGE: | |
5424 | page = target.page; | |
5425 | if (isolate_lru_page(page)) | |
5426 | goto put; | |
5427 | pc = lookup_page_cgroup(page); | |
7ec99d62 JW |
5428 | if (!mem_cgroup_move_account(page, 1, pc, |
5429 | mc.from, mc.to, false)) { | |
4ffef5fe | 5430 | mc.precharge--; |
854ffa8d DN |
5431 | /* we uncharge from mc.from later. */ |
5432 | mc.moved_charge++; | |
4ffef5fe DN |
5433 | } |
5434 | putback_lru_page(page); | |
5435 | put: /* is_target_pte_for_mc() gets the page */ | |
5436 | put_page(page); | |
5437 | break; | |
02491447 DN |
5438 | case MC_TARGET_SWAP: |
5439 | ent = target.ent; | |
483c30b5 DN |
5440 | if (!mem_cgroup_move_swap_account(ent, |
5441 | mc.from, mc.to, false)) { | |
02491447 | 5442 | mc.precharge--; |
483c30b5 DN |
5443 | /* we fixup refcnts and charges later. */ |
5444 | mc.moved_swap++; | |
5445 | } | |
02491447 | 5446 | break; |
4ffef5fe DN |
5447 | default: |
5448 | break; | |
5449 | } | |
5450 | } | |
5451 | pte_unmap_unlock(pte - 1, ptl); | |
5452 | cond_resched(); | |
5453 | ||
5454 | if (addr != end) { | |
5455 | /* | |
5456 | * We have consumed all precharges we got in can_attach(). | |
5457 | * We try charge one by one, but don't do any additional | |
5458 | * charges to mc.to if we have failed in charge once in attach() | |
5459 | * phase. | |
5460 | */ | |
854ffa8d | 5461 | ret = mem_cgroup_do_precharge(1); |
4ffef5fe DN |
5462 | if (!ret) |
5463 | goto retry; | |
5464 | } | |
5465 | ||
5466 | return ret; | |
5467 | } | |
5468 | ||
5469 | static void mem_cgroup_move_charge(struct mm_struct *mm) | |
5470 | { | |
5471 | struct vm_area_struct *vma; | |
5472 | ||
5473 | lru_add_drain_all(); | |
dfe076b0 DN |
5474 | retry: |
5475 | if (unlikely(!down_read_trylock(&mm->mmap_sem))) { | |
5476 | /* | |
5477 | * Someone who are holding the mmap_sem might be waiting in | |
5478 | * waitq. So we cancel all extra charges, wake up all waiters, | |
5479 | * and retry. Because we cancel precharges, we might not be able | |
5480 | * to move enough charges, but moving charge is a best-effort | |
5481 | * feature anyway, so it wouldn't be a big problem. | |
5482 | */ | |
5483 | __mem_cgroup_clear_mc(); | |
5484 | cond_resched(); | |
5485 | goto retry; | |
5486 | } | |
4ffef5fe DN |
5487 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
5488 | int ret; | |
5489 | struct mm_walk mem_cgroup_move_charge_walk = { | |
5490 | .pmd_entry = mem_cgroup_move_charge_pte_range, | |
5491 | .mm = mm, | |
5492 | .private = vma, | |
5493 | }; | |
5494 | if (is_vm_hugetlb_page(vma)) | |
5495 | continue; | |
4ffef5fe DN |
5496 | ret = walk_page_range(vma->vm_start, vma->vm_end, |
5497 | &mem_cgroup_move_charge_walk); | |
5498 | if (ret) | |
5499 | /* | |
5500 | * means we have consumed all precharges and failed in | |
5501 | * doing additional charge. Just abandon here. | |
5502 | */ | |
5503 | break; | |
5504 | } | |
dfe076b0 | 5505 | up_read(&mm->mmap_sem); |
7dc74be0 DN |
5506 | } |
5507 | ||
67e465a7 BS |
5508 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, |
5509 | struct cgroup *cont, | |
5510 | struct cgroup *old_cont, | |
f780bdb7 | 5511 | struct task_struct *p) |
67e465a7 | 5512 | { |
a433658c | 5513 | struct mm_struct *mm = get_task_mm(p); |
dfe076b0 | 5514 | |
dfe076b0 | 5515 | if (mm) { |
a433658c KM |
5516 | if (mc.to) |
5517 | mem_cgroup_move_charge(mm); | |
5518 | put_swap_token(mm); | |
dfe076b0 DN |
5519 | mmput(mm); |
5520 | } | |
a433658c KM |
5521 | if (mc.to) |
5522 | mem_cgroup_clear_mc(); | |
67e465a7 | 5523 | } |
5cfb80a7 DN |
5524 | #else /* !CONFIG_MMU */ |
5525 | static int mem_cgroup_can_attach(struct cgroup_subsys *ss, | |
5526 | struct cgroup *cgroup, | |
f780bdb7 | 5527 | struct task_struct *p) |
5cfb80a7 DN |
5528 | { |
5529 | return 0; | |
5530 | } | |
5531 | static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, | |
5532 | struct cgroup *cgroup, | |
f780bdb7 | 5533 | struct task_struct *p) |
5cfb80a7 DN |
5534 | { |
5535 | } | |
5536 | static void mem_cgroup_move_task(struct cgroup_subsys *ss, | |
5537 | struct cgroup *cont, | |
5538 | struct cgroup *old_cont, | |
f780bdb7 | 5539 | struct task_struct *p) |
5cfb80a7 DN |
5540 | { |
5541 | } | |
5542 | #endif | |
67e465a7 | 5543 | |
8cdea7c0 BS |
5544 | struct cgroup_subsys mem_cgroup_subsys = { |
5545 | .name = "memory", | |
5546 | .subsys_id = mem_cgroup_subsys_id, | |
5547 | .create = mem_cgroup_create, | |
df878fb0 | 5548 | .pre_destroy = mem_cgroup_pre_destroy, |
8cdea7c0 BS |
5549 | .destroy = mem_cgroup_destroy, |
5550 | .populate = mem_cgroup_populate, | |
7dc74be0 DN |
5551 | .can_attach = mem_cgroup_can_attach, |
5552 | .cancel_attach = mem_cgroup_cancel_attach, | |
67e465a7 | 5553 | .attach = mem_cgroup_move_task, |
6d12e2d8 | 5554 | .early_init = 0, |
04046e1a | 5555 | .use_id = 1, |
8cdea7c0 | 5556 | }; |
c077719b KH |
5557 | |
5558 | #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP | |
a42c390c MH |
5559 | static int __init enable_swap_account(char *s) |
5560 | { | |
5561 | /* consider enabled if no parameter or 1 is given */ | |
a2c8990a | 5562 | if (!strcmp(s, "1")) |
a42c390c | 5563 | really_do_swap_account = 1; |
a2c8990a | 5564 | else if (!strcmp(s, "0")) |
a42c390c MH |
5565 | really_do_swap_account = 0; |
5566 | return 1; | |
5567 | } | |
a2c8990a | 5568 | __setup("swapaccount=", enable_swap_account); |
c077719b | 5569 | |
c077719b | 5570 | #endif |