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Balbir Singh8cdea7c2008-02-07 00:13:50 -08001/* memcontrol.c - Memory Controller
2 *
3 * Copyright IBM Corporation, 2007
4 * Author Balbir Singh <balbir@linux.vnet.ibm.com>
5 *
Pavel Emelianov78fb7462008-02-07 00:13:51 -08006 * Copyright 2007 OpenVZ SWsoft Inc
7 * Author: Pavel Emelianov <xemul@openvz.org>
8 *
Balbir Singh8cdea7c2008-02-07 00:13:50 -08009 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 */
19
20#include <linux/res_counter.h>
21#include <linux/memcontrol.h>
22#include <linux/cgroup.h>
Pavel Emelianov78fb7462008-02-07 00:13:51 -080023#include <linux/mm.h>
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -080024#include <linux/smp.h>
Balbir Singh8a9f3cc2008-02-07 00:13:53 -080025#include <linux/page-flags.h>
Balbir Singh66e17072008-02-07 00:13:56 -080026#include <linux/backing-dev.h>
Balbir Singh8a9f3cc2008-02-07 00:13:53 -080027#include <linux/bit_spinlock.h>
28#include <linux/rcupdate.h>
Balbir Singh66e17072008-02-07 00:13:56 -080029#include <linux/swap.h>
30#include <linux/spinlock.h>
31#include <linux/fs.h>
KAMEZAWA Hiroyukid2ceb9b2008-02-07 00:14:25 -080032#include <linux/seq_file.h>
Balbir Singh8cdea7c2008-02-07 00:13:50 -080033
Balbir Singh8697d332008-02-07 00:13:59 -080034#include <asm/uaccess.h>
35
Balbir Singh8cdea7c2008-02-07 00:13:50 -080036struct cgroup_subsys mem_cgroup_subsys;
Balbir Singh66e17072008-02-07 00:13:56 -080037static const int MEM_CGROUP_RECLAIM_RETRIES = 5;
Balbir Singh8cdea7c2008-02-07 00:13:50 -080038
39/*
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -080040 * Statistics for memory cgroup.
41 */
42enum mem_cgroup_stat_index {
43 /*
44 * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
45 */
46 MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */
47 MEM_CGROUP_STAT_RSS, /* # of pages charged as rss */
48
49 MEM_CGROUP_STAT_NSTATS,
50};
51
52struct mem_cgroup_stat_cpu {
53 s64 count[MEM_CGROUP_STAT_NSTATS];
54} ____cacheline_aligned_in_smp;
55
56struct mem_cgroup_stat {
57 struct mem_cgroup_stat_cpu cpustat[NR_CPUS];
58};
59
60/*
61 * For accounting under irq disable, no need for increment preempt count.
62 */
63static void __mem_cgroup_stat_add_safe(struct mem_cgroup_stat *stat,
64 enum mem_cgroup_stat_index idx, int val)
65{
66 int cpu = smp_processor_id();
67 stat->cpustat[cpu].count[idx] += val;
68}
69
70static s64 mem_cgroup_read_stat(struct mem_cgroup_stat *stat,
71 enum mem_cgroup_stat_index idx)
72{
73 int cpu;
74 s64 ret = 0;
75 for_each_possible_cpu(cpu)
76 ret += stat->cpustat[cpu].count[idx];
77 return ret;
78}
79
80/*
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -080081 * per-zone information in memory controller.
82 */
83
84enum mem_cgroup_zstat_index {
85 MEM_CGROUP_ZSTAT_ACTIVE,
86 MEM_CGROUP_ZSTAT_INACTIVE,
87
88 NR_MEM_CGROUP_ZSTAT,
89};
90
91struct mem_cgroup_per_zone {
92 unsigned long count[NR_MEM_CGROUP_ZSTAT];
93};
94/* Macro for accessing counter */
95#define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)])
96
97struct mem_cgroup_per_node {
98 struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES];
99};
100
101struct mem_cgroup_lru_info {
102 struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES];
103};
104
105/*
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800106 * The memory controller data structure. The memory controller controls both
107 * page cache and RSS per cgroup. We would eventually like to provide
108 * statistics based on the statistics developed by Rik Van Riel for clock-pro,
109 * to help the administrator determine what knobs to tune.
110 *
111 * TODO: Add a water mark for the memory controller. Reclaim will begin when
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800112 * we hit the water mark. May be even add a low water mark, such that
113 * no reclaim occurs from a cgroup at it's low water mark, this is
114 * a feature that will be implemented much later in the future.
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800115 */
116struct mem_cgroup {
117 struct cgroup_subsys_state css;
118 /*
119 * the counter to account for memory usage
120 */
121 struct res_counter res;
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800122 /*
123 * Per cgroup active and inactive list, similar to the
124 * per zone LRU lists.
125 * TODO: Consider making these lists per zone
126 */
127 struct list_head active_list;
128 struct list_head inactive_list;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800129 struct mem_cgroup_lru_info info;
Balbir Singh66e17072008-02-07 00:13:56 -0800130 /*
131 * spin_lock to protect the per cgroup LRU
132 */
133 spinlock_t lru_lock;
Balbir Singh8697d332008-02-07 00:13:59 -0800134 unsigned long control_type; /* control RSS or RSS+Pagecache */
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800135 /*
136 * statistics.
137 */
138 struct mem_cgroup_stat stat;
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800139};
140
141/*
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800142 * We use the lower bit of the page->page_cgroup pointer as a bit spin
143 * lock. We need to ensure that page->page_cgroup is atleast two
144 * byte aligned (based on comments from Nick Piggin)
145 */
146#define PAGE_CGROUP_LOCK_BIT 0x0
147#define PAGE_CGROUP_LOCK (1 << PAGE_CGROUP_LOCK_BIT)
148
149/*
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800150 * A page_cgroup page is associated with every page descriptor. The
151 * page_cgroup helps us identify information about the cgroup
152 */
153struct page_cgroup {
154 struct list_head lru; /* per cgroup LRU list */
155 struct page *page;
156 struct mem_cgroup *mem_cgroup;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800157 atomic_t ref_cnt; /* Helpful when pages move b/w */
158 /* mapped and cached states */
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800159 int flags;
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800160};
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800161#define PAGE_CGROUP_FLAG_CACHE (0x1) /* charged as cache */
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800162#define PAGE_CGROUP_FLAG_ACTIVE (0x2) /* page is active in this cgroup */
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800163
KAMEZAWA Hiroyukic0149532008-02-07 00:14:30 -0800164static inline int page_cgroup_nid(struct page_cgroup *pc)
165{
166 return page_to_nid(pc->page);
167}
168
169static inline enum zone_type page_cgroup_zid(struct page_cgroup *pc)
170{
171 return page_zonenum(pc->page);
172}
173
Balbir Singh8697d332008-02-07 00:13:59 -0800174enum {
175 MEM_CGROUP_TYPE_UNSPEC = 0,
176 MEM_CGROUP_TYPE_MAPPED,
177 MEM_CGROUP_TYPE_CACHED,
178 MEM_CGROUP_TYPE_ALL,
179 MEM_CGROUP_TYPE_MAX,
180};
181
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800182enum charge_type {
183 MEM_CGROUP_CHARGE_TYPE_CACHE = 0,
184 MEM_CGROUP_CHARGE_TYPE_MAPPED,
185};
186
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800187
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800188/*
189 * Always modified under lru lock. Then, not necessary to preempt_disable()
190 */
191static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, int flags,
192 bool charge)
193{
194 int val = (charge)? 1 : -1;
195 struct mem_cgroup_stat *stat = &mem->stat;
196 VM_BUG_ON(!irqs_disabled());
197
198 if (flags & PAGE_CGROUP_FLAG_CACHE)
199 __mem_cgroup_stat_add_safe(stat,
200 MEM_CGROUP_STAT_CACHE, val);
201 else
202 __mem_cgroup_stat_add_safe(stat, MEM_CGROUP_STAT_RSS, val);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800203}
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800204
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800205static inline struct mem_cgroup_per_zone *
206mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid)
207{
208 BUG_ON(!mem->info.nodeinfo[nid]);
209 return &mem->info.nodeinfo[nid]->zoneinfo[zid];
210}
211
212static inline struct mem_cgroup_per_zone *
213page_cgroup_zoneinfo(struct page_cgroup *pc)
214{
215 struct mem_cgroup *mem = pc->mem_cgroup;
216 int nid = page_cgroup_nid(pc);
217 int zid = page_cgroup_zid(pc);
218
219 return mem_cgroup_zoneinfo(mem, nid, zid);
220}
221
222static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup *mem,
223 enum mem_cgroup_zstat_index idx)
224{
225 int nid, zid;
226 struct mem_cgroup_per_zone *mz;
227 u64 total = 0;
228
229 for_each_online_node(nid)
230 for (zid = 0; zid < MAX_NR_ZONES; zid++) {
231 mz = mem_cgroup_zoneinfo(mem, nid, zid);
232 total += MEM_CGROUP_ZSTAT(mz, idx);
233 }
234 return total;
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800235}
236
Balbir Singh8697d332008-02-07 00:13:59 -0800237static struct mem_cgroup init_mem_cgroup;
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800238
239static inline
240struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont)
241{
242 return container_of(cgroup_subsys_state(cont,
243 mem_cgroup_subsys_id), struct mem_cgroup,
244 css);
245}
246
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800247static inline
248struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p)
249{
250 return container_of(task_subsys_state(p, mem_cgroup_subsys_id),
251 struct mem_cgroup, css);
252}
253
254void mm_init_cgroup(struct mm_struct *mm, struct task_struct *p)
255{
256 struct mem_cgroup *mem;
257
258 mem = mem_cgroup_from_task(p);
259 css_get(&mem->css);
260 mm->mem_cgroup = mem;
261}
262
263void mm_free_cgroup(struct mm_struct *mm)
264{
265 css_put(&mm->mem_cgroup->css);
266}
267
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800268static inline int page_cgroup_locked(struct page *page)
269{
270 return bit_spin_is_locked(PAGE_CGROUP_LOCK_BIT,
271 &page->page_cgroup);
272}
273
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800274void page_assign_page_cgroup(struct page *page, struct page_cgroup *pc)
275{
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800276 int locked;
277
278 /*
279 * While resetting the page_cgroup we might not hold the
280 * page_cgroup lock. free_hot_cold_page() is an example
281 * of such a scenario
282 */
283 if (pc)
284 VM_BUG_ON(!page_cgroup_locked(page));
285 locked = (page->page_cgroup & PAGE_CGROUP_LOCK);
286 page->page_cgroup = ((unsigned long)pc | locked);
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800287}
288
289struct page_cgroup *page_get_page_cgroup(struct page *page)
290{
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800291 return (struct page_cgroup *)
292 (page->page_cgroup & ~PAGE_CGROUP_LOCK);
293}
294
Balbir Singh8697d332008-02-07 00:13:59 -0800295static void __always_inline lock_page_cgroup(struct page *page)
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800296{
297 bit_spin_lock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
298 VM_BUG_ON(!page_cgroup_locked(page));
299}
300
Balbir Singh8697d332008-02-07 00:13:59 -0800301static void __always_inline unlock_page_cgroup(struct page *page)
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800302{
303 bit_spin_unlock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
304}
305
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800306/*
307 * Tie new page_cgroup to struct page under lock_page_cgroup()
308 * This can fail if the page has been tied to a page_cgroup.
309 * If success, returns 0.
310 */
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800311static int page_cgroup_assign_new_page_cgroup(struct page *page,
312 struct page_cgroup *pc)
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800313{
314 int ret = 0;
315
316 lock_page_cgroup(page);
317 if (!page_get_page_cgroup(page))
318 page_assign_page_cgroup(page, pc);
319 else /* A page is tied to other pc. */
320 ret = 1;
321 unlock_page_cgroup(page);
322 return ret;
323}
324
325/*
326 * Clear page->page_cgroup member under lock_page_cgroup().
327 * If given "pc" value is different from one page->page_cgroup,
328 * page->cgroup is not cleared.
329 * Returns a value of page->page_cgroup at lock taken.
330 * A can can detect failure of clearing by following
331 * clear_page_cgroup(page, pc) == pc
332 */
333
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800334static struct page_cgroup *clear_page_cgroup(struct page *page,
335 struct page_cgroup *pc)
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800336{
337 struct page_cgroup *ret;
338 /* lock and clear */
339 lock_page_cgroup(page);
340 ret = page_get_page_cgroup(page);
341 if (likely(ret == pc))
342 page_assign_page_cgroup(page, NULL);
343 unlock_page_cgroup(page);
344 return ret;
345}
346
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800347static void __mem_cgroup_remove_list(struct page_cgroup *pc)
348{
349 int from = pc->flags & PAGE_CGROUP_FLAG_ACTIVE;
350 struct mem_cgroup_per_zone *mz = page_cgroup_zoneinfo(pc);
351
352 if (from)
353 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) -= 1;
354 else
355 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) -= 1;
356
357 mem_cgroup_charge_statistics(pc->mem_cgroup, pc->flags, false);
358 list_del_init(&pc->lru);
359}
360
361static void __mem_cgroup_add_list(struct page_cgroup *pc)
362{
363 int to = pc->flags & PAGE_CGROUP_FLAG_ACTIVE;
364 struct mem_cgroup_per_zone *mz = page_cgroup_zoneinfo(pc);
365
366 if (!to) {
367 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) += 1;
368 list_add(&pc->lru, &pc->mem_cgroup->inactive_list);
369 } else {
370 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) += 1;
371 list_add(&pc->lru, &pc->mem_cgroup->active_list);
372 }
373 mem_cgroup_charge_statistics(pc->mem_cgroup, pc->flags, true);
374}
375
Balbir Singh8697d332008-02-07 00:13:59 -0800376static void __mem_cgroup_move_lists(struct page_cgroup *pc, bool active)
Balbir Singh66e17072008-02-07 00:13:56 -0800377{
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800378 int from = pc->flags & PAGE_CGROUP_FLAG_ACTIVE;
379 struct mem_cgroup_per_zone *mz = page_cgroup_zoneinfo(pc);
380
381 if (from)
382 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) -= 1;
383 else
384 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) -= 1;
385
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800386 if (active) {
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800387 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) += 1;
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800388 pc->flags |= PAGE_CGROUP_FLAG_ACTIVE;
Balbir Singh66e17072008-02-07 00:13:56 -0800389 list_move(&pc->lru, &pc->mem_cgroup->active_list);
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800390 } else {
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800391 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) += 1;
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800392 pc->flags &= ~PAGE_CGROUP_FLAG_ACTIVE;
Balbir Singh66e17072008-02-07 00:13:56 -0800393 list_move(&pc->lru, &pc->mem_cgroup->inactive_list);
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800394 }
Balbir Singh66e17072008-02-07 00:13:56 -0800395}
396
David Rientjes4c4a2212008-02-07 00:14:06 -0800397int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem)
398{
399 int ret;
400
401 task_lock(task);
402 ret = task->mm && mm_cgroup(task->mm) == mem;
403 task_unlock(task);
404 return ret;
405}
406
Balbir Singh66e17072008-02-07 00:13:56 -0800407/*
408 * This routine assumes that the appropriate zone's lru lock is already held
409 */
410void mem_cgroup_move_lists(struct page_cgroup *pc, bool active)
411{
412 struct mem_cgroup *mem;
413 if (!pc)
414 return;
415
416 mem = pc->mem_cgroup;
417
418 spin_lock(&mem->lru_lock);
419 __mem_cgroup_move_lists(pc, active);
420 spin_unlock(&mem->lru_lock);
421}
422
KAMEZAWA Hiroyuki58ae83d2008-02-07 00:14:32 -0800423/*
424 * Calculate mapped_ratio under memory controller. This will be used in
425 * vmscan.c for deteremining we have to reclaim mapped pages.
426 */
427int mem_cgroup_calc_mapped_ratio(struct mem_cgroup *mem)
428{
429 long total, rss;
430
431 /*
432 * usage is recorded in bytes. But, here, we assume the number of
433 * physical pages can be represented by "long" on any arch.
434 */
435 total = (long) (mem->res.usage >> PAGE_SHIFT) + 1L;
436 rss = (long)mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_RSS);
437 return (int)((rss * 100L) / total);
438}
KAMEZAWA Hiroyuki5932f362008-02-07 00:14:33 -0800439/*
440 * This function is called from vmscan.c. In page reclaiming loop. balance
441 * between active and inactive list is calculated. For memory controller
442 * page reclaiming, we should use using mem_cgroup's imbalance rather than
443 * zone's global lru imbalance.
444 */
445long mem_cgroup_reclaim_imbalance(struct mem_cgroup *mem)
446{
447 unsigned long active, inactive;
448 /* active and inactive are the number of pages. 'long' is ok.*/
449 active = mem_cgroup_get_all_zonestat(mem, MEM_CGROUP_ZSTAT_ACTIVE);
450 inactive = mem_cgroup_get_all_zonestat(mem, MEM_CGROUP_ZSTAT_INACTIVE);
451 return (long) (active / (inactive + 1));
452}
KAMEZAWA Hiroyuki58ae83d2008-02-07 00:14:32 -0800453
Balbir Singh66e17072008-02-07 00:13:56 -0800454unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
455 struct list_head *dst,
456 unsigned long *scanned, int order,
457 int mode, struct zone *z,
458 struct mem_cgroup *mem_cont,
459 int active)
460{
461 unsigned long nr_taken = 0;
462 struct page *page;
463 unsigned long scan;
464 LIST_HEAD(pc_list);
465 struct list_head *src;
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800466 struct page_cgroup *pc, *tmp;
Balbir Singh66e17072008-02-07 00:13:56 -0800467
468 if (active)
469 src = &mem_cont->active_list;
470 else
471 src = &mem_cont->inactive_list;
472
473 spin_lock(&mem_cont->lru_lock);
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800474 scan = 0;
475 list_for_each_entry_safe_reverse(pc, tmp, src, lru) {
Hugh Dickins436c65412008-02-07 00:14:12 -0800476 if (scan >= nr_to_scan)
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800477 break;
Balbir Singh66e17072008-02-07 00:13:56 -0800478 page = pc->page;
479 VM_BUG_ON(!pc);
480
Hugh Dickins436c65412008-02-07 00:14:12 -0800481 if (unlikely(!PageLRU(page)))
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800482 continue;
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800483
Balbir Singh66e17072008-02-07 00:13:56 -0800484 if (PageActive(page) && !active) {
485 __mem_cgroup_move_lists(pc, true);
Balbir Singh66e17072008-02-07 00:13:56 -0800486 continue;
487 }
488 if (!PageActive(page) && active) {
489 __mem_cgroup_move_lists(pc, false);
Balbir Singh66e17072008-02-07 00:13:56 -0800490 continue;
491 }
492
493 /*
494 * Reclaim, per zone
495 * TODO: make the active/inactive lists per zone
496 */
497 if (page_zone(page) != z)
498 continue;
499
Hugh Dickins436c65412008-02-07 00:14:12 -0800500 scan++;
501 list_move(&pc->lru, &pc_list);
Balbir Singh66e17072008-02-07 00:13:56 -0800502
503 if (__isolate_lru_page(page, mode) == 0) {
504 list_move(&page->lru, dst);
505 nr_taken++;
506 }
507 }
508
509 list_splice(&pc_list, src);
510 spin_unlock(&mem_cont->lru_lock);
511
512 *scanned = scan;
513 return nr_taken;
514}
515
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800516/*
517 * Charge the memory controller for page usage.
518 * Return
519 * 0 if the charge was successful
520 * < 0 if the cgroup is over its limit
521 */
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800522static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
523 gfp_t gfp_mask, enum charge_type ctype)
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800524{
525 struct mem_cgroup *mem;
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800526 struct page_cgroup *pc;
Balbir Singh66e17072008-02-07 00:13:56 -0800527 unsigned long flags;
528 unsigned long nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800529
530 /*
531 * Should page_cgroup's go to their own slab?
532 * One could optimize the performance of the charging routine
533 * by saving a bit in the page_flags and using it as a lock
534 * to see if the cgroup page already has a page_cgroup associated
535 * with it
536 */
Balbir Singh66e17072008-02-07 00:13:56 -0800537retry:
Hugh Dickins82369552008-02-07 00:14:22 -0800538 if (page) {
539 lock_page_cgroup(page);
540 pc = page_get_page_cgroup(page);
541 /*
542 * The page_cgroup exists and
543 * the page has already been accounted.
544 */
545 if (pc) {
546 if (unlikely(!atomic_inc_not_zero(&pc->ref_cnt))) {
547 /* this page is under being uncharged ? */
548 unlock_page_cgroup(page);
549 cpu_relax();
550 goto retry;
551 } else {
552 unlock_page_cgroup(page);
553 goto done;
554 }
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800555 }
Hugh Dickins82369552008-02-07 00:14:22 -0800556 unlock_page_cgroup(page);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800557 }
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800558
Balbir Singhe1a1cd52008-02-07 00:14:02 -0800559 pc = kzalloc(sizeof(struct page_cgroup), gfp_mask);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800560 if (pc == NULL)
561 goto err;
562
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800563 /*
Hugh Dickins3be91272008-02-07 00:14:19 -0800564 * We always charge the cgroup the mm_struct belongs to.
565 * The mm_struct's mem_cgroup changes on task migration if the
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800566 * thread group leader migrates. It's possible that mm is not
567 * set, if so charge the init_mm (happens for pagecache usage).
568 */
569 if (!mm)
570 mm = &init_mm;
571
Hugh Dickins3be91272008-02-07 00:14:19 -0800572 rcu_read_lock();
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800573 mem = rcu_dereference(mm->mem_cgroup);
574 /*
575 * For every charge from the cgroup, increment reference
576 * count
577 */
578 css_get(&mem->css);
579 rcu_read_unlock();
580
581 /*
582 * If we created the page_cgroup, we should free it on exceeding
583 * the cgroup limit.
584 */
Balbir Singh0eea1032008-02-07 00:13:57 -0800585 while (res_counter_charge(&mem->res, PAGE_SIZE)) {
Hugh Dickins3be91272008-02-07 00:14:19 -0800586 if (!(gfp_mask & __GFP_WAIT))
587 goto out;
Balbir Singhe1a1cd52008-02-07 00:14:02 -0800588
589 if (try_to_free_mem_cgroup_pages(mem, gfp_mask))
Balbir Singh66e17072008-02-07 00:13:56 -0800590 continue;
591
592 /*
593 * try_to_free_mem_cgroup_pages() might not give us a full
594 * picture of reclaim. Some pages are reclaimed and might be
595 * moved to swap cache or just unmapped from the cgroup.
596 * Check the limit again to see if the reclaim reduced the
597 * current usage of the cgroup before giving up
598 */
599 if (res_counter_check_under_limit(&mem->res))
600 continue;
Hugh Dickins3be91272008-02-07 00:14:19 -0800601
602 if (!nr_retries--) {
603 mem_cgroup_out_of_memory(mem, gfp_mask);
604 goto out;
Balbir Singh66e17072008-02-07 00:13:56 -0800605 }
Hugh Dickins3be91272008-02-07 00:14:19 -0800606 congestion_wait(WRITE, HZ/10);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800607 }
608
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800609 atomic_set(&pc->ref_cnt, 1);
610 pc->mem_cgroup = mem;
611 pc->page = page;
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800612 pc->flags = PAGE_CGROUP_FLAG_ACTIVE;
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800613 if (ctype == MEM_CGROUP_CHARGE_TYPE_CACHE)
614 pc->flags |= PAGE_CGROUP_FLAG_CACHE;
Hugh Dickins3be91272008-02-07 00:14:19 -0800615
Hugh Dickins82369552008-02-07 00:14:22 -0800616 if (!page || page_cgroup_assign_new_page_cgroup(page, pc)) {
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800617 /*
Hugh Dickins3be91272008-02-07 00:14:19 -0800618 * Another charge has been added to this page already.
619 * We take lock_page_cgroup(page) again and read
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800620 * page->cgroup, increment refcnt.... just retry is OK.
621 */
622 res_counter_uncharge(&mem->res, PAGE_SIZE);
623 css_put(&mem->css);
624 kfree(pc);
Hugh Dickins82369552008-02-07 00:14:22 -0800625 if (!page)
626 goto done;
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800627 goto retry;
628 }
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800629
Balbir Singh66e17072008-02-07 00:13:56 -0800630 spin_lock_irqsave(&mem->lru_lock, flags);
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800631 /* Update statistics vector */
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800632 __mem_cgroup_add_list(pc);
Balbir Singh66e17072008-02-07 00:13:56 -0800633 spin_unlock_irqrestore(&mem->lru_lock, flags);
634
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800635done:
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800636 return 0;
Hugh Dickins3be91272008-02-07 00:14:19 -0800637out:
638 css_put(&mem->css);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800639 kfree(pc);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800640err:
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800641 return -ENOMEM;
642}
643
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800644int mem_cgroup_charge(struct page *page, struct mm_struct *mm,
645 gfp_t gfp_mask)
646{
647 return mem_cgroup_charge_common(page, mm, gfp_mask,
648 MEM_CGROUP_CHARGE_TYPE_MAPPED);
649}
650
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800651/*
Balbir Singh8697d332008-02-07 00:13:59 -0800652 * See if the cached pages should be charged at all?
653 */
Balbir Singhe1a1cd52008-02-07 00:14:02 -0800654int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
655 gfp_t gfp_mask)
Balbir Singh8697d332008-02-07 00:13:59 -0800656{
Balbir Singhac44d352008-02-07 00:14:18 -0800657 int ret = 0;
Balbir Singh8697d332008-02-07 00:13:59 -0800658 struct mem_cgroup *mem;
659 if (!mm)
660 mm = &init_mm;
661
Balbir Singhac44d352008-02-07 00:14:18 -0800662 rcu_read_lock();
Balbir Singh8697d332008-02-07 00:13:59 -0800663 mem = rcu_dereference(mm->mem_cgroup);
Balbir Singhac44d352008-02-07 00:14:18 -0800664 css_get(&mem->css);
665 rcu_read_unlock();
Balbir Singh8697d332008-02-07 00:13:59 -0800666 if (mem->control_type == MEM_CGROUP_TYPE_ALL)
Balbir Singhac44d352008-02-07 00:14:18 -0800667 ret = mem_cgroup_charge_common(page, mm, gfp_mask,
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800668 MEM_CGROUP_CHARGE_TYPE_CACHE);
Balbir Singhac44d352008-02-07 00:14:18 -0800669 css_put(&mem->css);
670 return ret;
Balbir Singh8697d332008-02-07 00:13:59 -0800671}
672
673/*
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800674 * Uncharging is always a welcome operation, we never complain, simply
675 * uncharge.
676 */
677void mem_cgroup_uncharge(struct page_cgroup *pc)
678{
679 struct mem_cgroup *mem;
680 struct page *page;
Balbir Singh66e17072008-02-07 00:13:56 -0800681 unsigned long flags;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800682
Balbir Singh8697d332008-02-07 00:13:59 -0800683 /*
684 * This can handle cases when a page is not charged at all and we
685 * are switching between handling the control_type.
686 */
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800687 if (!pc)
688 return;
689
690 if (atomic_dec_and_test(&pc->ref_cnt)) {
691 page = pc->page;
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800692 /*
693 * get page->cgroup and clear it under lock.
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800694 * force_empty can drop page->cgroup without checking refcnt.
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800695 */
696 if (clear_page_cgroup(page, pc) == pc) {
697 mem = pc->mem_cgroup;
698 css_put(&mem->css);
699 res_counter_uncharge(&mem->res, PAGE_SIZE);
700 spin_lock_irqsave(&mem->lru_lock, flags);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800701 __mem_cgroup_remove_list(pc);
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800702 spin_unlock_irqrestore(&mem->lru_lock, flags);
703 kfree(pc);
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800704 }
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800705 }
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800706}
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800707
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800708/*
709 * Returns non-zero if a page (under migration) has valid page_cgroup member.
710 * Refcnt of page_cgroup is incremented.
711 */
712
713int mem_cgroup_prepare_migration(struct page *page)
714{
715 struct page_cgroup *pc;
716 int ret = 0;
717 lock_page_cgroup(page);
718 pc = page_get_page_cgroup(page);
719 if (pc && atomic_inc_not_zero(&pc->ref_cnt))
720 ret = 1;
721 unlock_page_cgroup(page);
722 return ret;
723}
724
725void mem_cgroup_end_migration(struct page *page)
726{
727 struct page_cgroup *pc = page_get_page_cgroup(page);
728 mem_cgroup_uncharge(pc);
729}
730/*
731 * We know both *page* and *newpage* are now not-on-LRU and Pg_locked.
732 * And no race with uncharge() routines because page_cgroup for *page*
733 * has extra one reference by mem_cgroup_prepare_migration.
734 */
735
736void mem_cgroup_page_migration(struct page *page, struct page *newpage)
737{
738 struct page_cgroup *pc;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800739 struct mem_cgroup *mem;
740 unsigned long flags;
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800741retry:
742 pc = page_get_page_cgroup(page);
743 if (!pc)
744 return;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800745 mem = pc->mem_cgroup;
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800746 if (clear_page_cgroup(page, pc) != pc)
747 goto retry;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800748
749 spin_lock_irqsave(&mem->lru_lock, flags);
750
751 __mem_cgroup_remove_list(pc);
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800752 pc->page = newpage;
753 lock_page_cgroup(newpage);
754 page_assign_page_cgroup(newpage, pc);
755 unlock_page_cgroup(newpage);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800756 __mem_cgroup_add_list(pc);
757
758 spin_unlock_irqrestore(&mem->lru_lock, flags);
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800759 return;
760}
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800761
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800762/*
763 * This routine traverse page_cgroup in given list and drop them all.
764 * This routine ignores page_cgroup->ref_cnt.
765 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
766 */
767#define FORCE_UNCHARGE_BATCH (128)
768static void
769mem_cgroup_force_empty_list(struct mem_cgroup *mem, struct list_head *list)
770{
771 struct page_cgroup *pc;
772 struct page *page;
773 int count;
774 unsigned long flags;
775
776retry:
777 count = FORCE_UNCHARGE_BATCH;
778 spin_lock_irqsave(&mem->lru_lock, flags);
779
780 while (--count && !list_empty(list)) {
781 pc = list_entry(list->prev, struct page_cgroup, lru);
782 page = pc->page;
783 /* Avoid race with charge */
784 atomic_set(&pc->ref_cnt, 0);
785 if (clear_page_cgroup(page, pc) == pc) {
786 css_put(&mem->css);
787 res_counter_uncharge(&mem->res, PAGE_SIZE);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800788 __mem_cgroup_remove_list(pc);
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800789 kfree(pc);
790 } else /* being uncharged ? ...do relax */
791 break;
792 }
793 spin_unlock_irqrestore(&mem->lru_lock, flags);
794 if (!list_empty(list)) {
795 cond_resched();
796 goto retry;
797 }
798 return;
799}
800
801/*
802 * make mem_cgroup's charge to be 0 if there is no task.
803 * This enables deleting this mem_cgroup.
804 */
805
806int mem_cgroup_force_empty(struct mem_cgroup *mem)
807{
808 int ret = -EBUSY;
809 css_get(&mem->css);
810 /*
811 * page reclaim code (kswapd etc..) will move pages between
812` * active_list <-> inactive_list while we don't take a lock.
813 * So, we have to do loop here until all lists are empty.
814 */
815 while (!(list_empty(&mem->active_list) &&
816 list_empty(&mem->inactive_list))) {
817 if (atomic_read(&mem->css.cgroup->count) > 0)
818 goto out;
819 /* drop all page_cgroup in active_list */
820 mem_cgroup_force_empty_list(mem, &mem->active_list);
821 /* drop all page_cgroup in inactive_list */
822 mem_cgroup_force_empty_list(mem, &mem->inactive_list);
823 }
824 ret = 0;
825out:
826 css_put(&mem->css);
827 return ret;
828}
829
830
831
Balbir Singh0eea1032008-02-07 00:13:57 -0800832int mem_cgroup_write_strategy(char *buf, unsigned long long *tmp)
833{
834 *tmp = memparse(buf, &buf);
835 if (*buf != '\0')
836 return -EINVAL;
837
838 /*
839 * Round up the value to the closest page size
840 */
841 *tmp = ((*tmp + PAGE_SIZE - 1) >> PAGE_SHIFT) << PAGE_SHIFT;
842 return 0;
843}
844
845static ssize_t mem_cgroup_read(struct cgroup *cont,
846 struct cftype *cft, struct file *file,
847 char __user *userbuf, size_t nbytes, loff_t *ppos)
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800848{
849 return res_counter_read(&mem_cgroup_from_cont(cont)->res,
Balbir Singh0eea1032008-02-07 00:13:57 -0800850 cft->private, userbuf, nbytes, ppos,
851 NULL);
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800852}
853
854static ssize_t mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
855 struct file *file, const char __user *userbuf,
856 size_t nbytes, loff_t *ppos)
857{
858 return res_counter_write(&mem_cgroup_from_cont(cont)->res,
Balbir Singh0eea1032008-02-07 00:13:57 -0800859 cft->private, userbuf, nbytes, ppos,
860 mem_cgroup_write_strategy);
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800861}
862
Balbir Singh8697d332008-02-07 00:13:59 -0800863static ssize_t mem_control_type_write(struct cgroup *cont,
864 struct cftype *cft, struct file *file,
865 const char __user *userbuf,
866 size_t nbytes, loff_t *pos)
867{
868 int ret;
869 char *buf, *end;
870 unsigned long tmp;
871 struct mem_cgroup *mem;
872
873 mem = mem_cgroup_from_cont(cont);
874 buf = kmalloc(nbytes + 1, GFP_KERNEL);
875 ret = -ENOMEM;
876 if (buf == NULL)
877 goto out;
878
879 buf[nbytes] = 0;
880 ret = -EFAULT;
881 if (copy_from_user(buf, userbuf, nbytes))
882 goto out_free;
883
884 ret = -EINVAL;
885 tmp = simple_strtoul(buf, &end, 10);
886 if (*end != '\0')
887 goto out_free;
888
889 if (tmp <= MEM_CGROUP_TYPE_UNSPEC || tmp >= MEM_CGROUP_TYPE_MAX)
890 goto out_free;
891
892 mem->control_type = tmp;
893 ret = nbytes;
894out_free:
895 kfree(buf);
896out:
897 return ret;
898}
899
900static ssize_t mem_control_type_read(struct cgroup *cont,
901 struct cftype *cft,
902 struct file *file, char __user *userbuf,
903 size_t nbytes, loff_t *ppos)
904{
905 unsigned long val;
906 char buf[64], *s;
907 struct mem_cgroup *mem;
908
909 mem = mem_cgroup_from_cont(cont);
910 s = buf;
911 val = mem->control_type;
912 s += sprintf(s, "%lu\n", val);
913 return simple_read_from_buffer((void __user *)userbuf, nbytes,
914 ppos, buf, s - buf);
915}
916
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800917
918static ssize_t mem_force_empty_write(struct cgroup *cont,
919 struct cftype *cft, struct file *file,
920 const char __user *userbuf,
921 size_t nbytes, loff_t *ppos)
922{
923 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
924 int ret;
925 ret = mem_cgroup_force_empty(mem);
926 if (!ret)
927 ret = nbytes;
928 return ret;
929}
930
931/*
932 * Note: This should be removed if cgroup supports write-only file.
933 */
934
935static ssize_t mem_force_empty_read(struct cgroup *cont,
936 struct cftype *cft,
937 struct file *file, char __user *userbuf,
938 size_t nbytes, loff_t *ppos)
939{
940 return -EINVAL;
941}
942
943
KAMEZAWA Hiroyukid2ceb9b2008-02-07 00:14:25 -0800944static const struct mem_cgroup_stat_desc {
945 const char *msg;
946 u64 unit;
947} mem_cgroup_stat_desc[] = {
948 [MEM_CGROUP_STAT_CACHE] = { "cache", PAGE_SIZE, },
949 [MEM_CGROUP_STAT_RSS] = { "rss", PAGE_SIZE, },
950};
951
952static int mem_control_stat_show(struct seq_file *m, void *arg)
953{
954 struct cgroup *cont = m->private;
955 struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont);
956 struct mem_cgroup_stat *stat = &mem_cont->stat;
957 int i;
958
959 for (i = 0; i < ARRAY_SIZE(stat->cpustat[0].count); i++) {
960 s64 val;
961
962 val = mem_cgroup_read_stat(stat, i);
963 val *= mem_cgroup_stat_desc[i].unit;
964 seq_printf(m, "%s %lld\n", mem_cgroup_stat_desc[i].msg,
965 (long long)val);
966 }
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800967 /* showing # of active pages */
968 {
969 unsigned long active, inactive;
970
971 inactive = mem_cgroup_get_all_zonestat(mem_cont,
972 MEM_CGROUP_ZSTAT_INACTIVE);
973 active = mem_cgroup_get_all_zonestat(mem_cont,
974 MEM_CGROUP_ZSTAT_ACTIVE);
975 seq_printf(m, "active %ld\n", (active) * PAGE_SIZE);
976 seq_printf(m, "inactive %ld\n", (inactive) * PAGE_SIZE);
977 }
KAMEZAWA Hiroyukid2ceb9b2008-02-07 00:14:25 -0800978 return 0;
979}
980
981static const struct file_operations mem_control_stat_file_operations = {
982 .read = seq_read,
983 .llseek = seq_lseek,
984 .release = single_release,
985};
986
987static int mem_control_stat_open(struct inode *unused, struct file *file)
988{
989 /* XXX __d_cont */
990 struct cgroup *cont = file->f_dentry->d_parent->d_fsdata;
991
992 file->f_op = &mem_control_stat_file_operations;
993 return single_open(file, mem_control_stat_show, cont);
994}
995
996
997
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800998static struct cftype mem_cgroup_files[] = {
999 {
Balbir Singh0eea1032008-02-07 00:13:57 -08001000 .name = "usage_in_bytes",
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001001 .private = RES_USAGE,
1002 .read = mem_cgroup_read,
1003 },
1004 {
Balbir Singh0eea1032008-02-07 00:13:57 -08001005 .name = "limit_in_bytes",
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001006 .private = RES_LIMIT,
1007 .write = mem_cgroup_write,
1008 .read = mem_cgroup_read,
1009 },
1010 {
1011 .name = "failcnt",
1012 .private = RES_FAILCNT,
1013 .read = mem_cgroup_read,
1014 },
Balbir Singh8697d332008-02-07 00:13:59 -08001015 {
1016 .name = "control_type",
1017 .write = mem_control_type_write,
1018 .read = mem_control_type_read,
1019 },
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -08001020 {
1021 .name = "force_empty",
1022 .write = mem_force_empty_write,
1023 .read = mem_force_empty_read,
1024 },
KAMEZAWA Hiroyukid2ceb9b2008-02-07 00:14:25 -08001025 {
1026 .name = "stat",
1027 .open = mem_control_stat_open,
1028 },
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001029};
1030
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001031static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
1032{
1033 struct mem_cgroup_per_node *pn;
1034
1035 pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, node);
1036 if (!pn)
1037 return 1;
1038 mem->info.nodeinfo[node] = pn;
1039 memset(pn, 0, sizeof(*pn));
1040 return 0;
1041}
1042
Pavel Emelianov78fb7462008-02-07 00:13:51 -08001043static struct mem_cgroup init_mem_cgroup;
1044
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001045static struct cgroup_subsys_state *
1046mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
1047{
1048 struct mem_cgroup *mem;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001049 int node;
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001050
Pavel Emelianov78fb7462008-02-07 00:13:51 -08001051 if (unlikely((cont->parent) == NULL)) {
1052 mem = &init_mem_cgroup;
1053 init_mm.mem_cgroup = mem;
1054 } else
1055 mem = kzalloc(sizeof(struct mem_cgroup), GFP_KERNEL);
1056
1057 if (mem == NULL)
1058 return NULL;
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001059
1060 res_counter_init(&mem->res);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -08001061 INIT_LIST_HEAD(&mem->active_list);
1062 INIT_LIST_HEAD(&mem->inactive_list);
Balbir Singh66e17072008-02-07 00:13:56 -08001063 spin_lock_init(&mem->lru_lock);
Balbir Singh8697d332008-02-07 00:13:59 -08001064 mem->control_type = MEM_CGROUP_TYPE_ALL;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001065 memset(&mem->info, 0, sizeof(mem->info));
1066
1067 for_each_node_state(node, N_POSSIBLE)
1068 if (alloc_mem_cgroup_per_zone_info(mem, node))
1069 goto free_out;
1070
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001071 return &mem->css;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001072free_out:
1073 for_each_node_state(node, N_POSSIBLE)
1074 kfree(mem->info.nodeinfo[node]);
1075 if (cont->parent != NULL)
1076 kfree(mem);
1077 return NULL;
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001078}
1079
KAMEZAWA Hiroyukidf878fb2008-02-07 00:14:28 -08001080static void mem_cgroup_pre_destroy(struct cgroup_subsys *ss,
1081 struct cgroup *cont)
1082{
1083 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
1084 mem_cgroup_force_empty(mem);
1085}
1086
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001087static void mem_cgroup_destroy(struct cgroup_subsys *ss,
1088 struct cgroup *cont)
1089{
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001090 int node;
1091 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
1092
1093 for_each_node_state(node, N_POSSIBLE)
1094 kfree(mem->info.nodeinfo[node]);
1095
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001096 kfree(mem_cgroup_from_cont(cont));
1097}
1098
1099static int mem_cgroup_populate(struct cgroup_subsys *ss,
1100 struct cgroup *cont)
1101{
1102 return cgroup_add_files(cont, ss, mem_cgroup_files,
1103 ARRAY_SIZE(mem_cgroup_files));
1104}
1105
Balbir Singh67e465a2008-02-07 00:13:54 -08001106static void mem_cgroup_move_task(struct cgroup_subsys *ss,
1107 struct cgroup *cont,
1108 struct cgroup *old_cont,
1109 struct task_struct *p)
1110{
1111 struct mm_struct *mm;
1112 struct mem_cgroup *mem, *old_mem;
1113
1114 mm = get_task_mm(p);
1115 if (mm == NULL)
1116 return;
1117
1118 mem = mem_cgroup_from_cont(cont);
1119 old_mem = mem_cgroup_from_cont(old_cont);
1120
1121 if (mem == old_mem)
1122 goto out;
1123
1124 /*
1125 * Only thread group leaders are allowed to migrate, the mm_struct is
1126 * in effect owned by the leader
1127 */
1128 if (p->tgid != p->pid)
1129 goto out;
1130
1131 css_get(&mem->css);
1132 rcu_assign_pointer(mm->mem_cgroup, mem);
1133 css_put(&old_mem->css);
1134
1135out:
1136 mmput(mm);
1137 return;
1138}
1139
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001140struct cgroup_subsys mem_cgroup_subsys = {
1141 .name = "memory",
1142 .subsys_id = mem_cgroup_subsys_id,
1143 .create = mem_cgroup_create,
KAMEZAWA Hiroyukidf878fb2008-02-07 00:14:28 -08001144 .pre_destroy = mem_cgroup_pre_destroy,
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001145 .destroy = mem_cgroup_destroy,
1146 .populate = mem_cgroup_populate,
Balbir Singh67e465a2008-02-07 00:13:54 -08001147 .attach = mem_cgroup_move_task,
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001148 .early_init = 0,
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001149};