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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 {
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -080092 /*
93 * spin_lock to protect the per cgroup LRU
94 */
95 spinlock_t lru_lock;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -080096 struct list_head active_list;
97 struct list_head inactive_list;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -080098 unsigned long count[NR_MEM_CGROUP_ZSTAT];
99};
100/* Macro for accessing counter */
101#define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)])
102
103struct mem_cgroup_per_node {
104 struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES];
105};
106
107struct mem_cgroup_lru_info {
108 struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES];
109};
110
111/*
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800112 * The memory controller data structure. The memory controller controls both
113 * page cache and RSS per cgroup. We would eventually like to provide
114 * statistics based on the statistics developed by Rik Van Riel for clock-pro,
115 * to help the administrator determine what knobs to tune.
116 *
117 * TODO: Add a water mark for the memory controller. Reclaim will begin when
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800118 * we hit the water mark. May be even add a low water mark, such that
119 * no reclaim occurs from a cgroup at it's low water mark, this is
120 * a feature that will be implemented much later in the future.
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800121 */
122struct mem_cgroup {
123 struct cgroup_subsys_state css;
124 /*
125 * the counter to account for memory usage
126 */
127 struct res_counter res;
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800128 /*
129 * Per cgroup active and inactive list, similar to the
130 * per zone LRU lists.
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800131 */
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800132 struct mem_cgroup_lru_info info;
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800133
KAMEZAWA Hiroyuki6c48a1d2008-02-07 00:14:34 -0800134 int prev_priority; /* for recording reclaim priority */
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};
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800140static struct mem_cgroup init_mem_cgroup;
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800141
142/*
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800143 * We use the lower bit of the page->page_cgroup pointer as a bit spin
Hugh Dickins9442ec9d2008-03-04 14:29:07 -0800144 * lock. We need to ensure that page->page_cgroup is at least two
145 * byte aligned (based on comments from Nick Piggin). But since
146 * bit_spin_lock doesn't actually set that lock bit in a non-debug
147 * uniprocessor kernel, we should avoid setting it here too.
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800148 */
149#define PAGE_CGROUP_LOCK_BIT 0x0
Hugh Dickins9442ec9d2008-03-04 14:29:07 -0800150#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
151#define PAGE_CGROUP_LOCK (1 << PAGE_CGROUP_LOCK_BIT)
152#else
153#define PAGE_CGROUP_LOCK 0x0
154#endif
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800155
156/*
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800157 * A page_cgroup page is associated with every page descriptor. The
158 * page_cgroup helps us identify information about the cgroup
159 */
160struct page_cgroup {
161 struct list_head lru; /* per cgroup LRU list */
162 struct page *page;
163 struct mem_cgroup *mem_cgroup;
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800164 int ref_cnt; /* cached, mapped, migrating */
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800165 int flags;
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800166};
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800167#define PAGE_CGROUP_FLAG_CACHE (0x1) /* charged as cache */
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800168#define PAGE_CGROUP_FLAG_ACTIVE (0x2) /* page is active in this cgroup */
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800169
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800170static int page_cgroup_nid(struct page_cgroup *pc)
KAMEZAWA Hiroyukic0149532008-02-07 00:14:30 -0800171{
172 return page_to_nid(pc->page);
173}
174
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800175static enum zone_type page_cgroup_zid(struct page_cgroup *pc)
KAMEZAWA Hiroyukic0149532008-02-07 00:14:30 -0800176{
177 return page_zonenum(pc->page);
178}
179
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800180enum charge_type {
181 MEM_CGROUP_CHARGE_TYPE_CACHE = 0,
182 MEM_CGROUP_CHARGE_TYPE_MAPPED,
183};
184
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800185/*
186 * Always modified under lru lock. Then, not necessary to preempt_disable()
187 */
188static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, int flags,
189 bool charge)
190{
191 int val = (charge)? 1 : -1;
192 struct mem_cgroup_stat *stat = &mem->stat;
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800193
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800194 VM_BUG_ON(!irqs_disabled());
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800195 if (flags & PAGE_CGROUP_FLAG_CACHE)
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800196 __mem_cgroup_stat_add_safe(stat, MEM_CGROUP_STAT_CACHE, val);
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800197 else
198 __mem_cgroup_stat_add_safe(stat, MEM_CGROUP_STAT_RSS, val);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800199}
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800200
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800201static struct mem_cgroup_per_zone *
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800202mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid)
203{
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800204 return &mem->info.nodeinfo[nid]->zoneinfo[zid];
205}
206
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800207static struct mem_cgroup_per_zone *
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800208page_cgroup_zoneinfo(struct page_cgroup *pc)
209{
210 struct mem_cgroup *mem = pc->mem_cgroup;
211 int nid = page_cgroup_nid(pc);
212 int zid = page_cgroup_zid(pc);
213
214 return mem_cgroup_zoneinfo(mem, nid, zid);
215}
216
217static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup *mem,
218 enum mem_cgroup_zstat_index idx)
219{
220 int nid, zid;
221 struct mem_cgroup_per_zone *mz;
222 u64 total = 0;
223
224 for_each_online_node(nid)
225 for (zid = 0; zid < MAX_NR_ZONES; zid++) {
226 mz = mem_cgroup_zoneinfo(mem, nid, zid);
227 total += MEM_CGROUP_ZSTAT(mz, idx);
228 }
229 return total;
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800230}
231
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800232static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont)
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800233{
234 return container_of(cgroup_subsys_state(cont,
235 mem_cgroup_subsys_id), struct mem_cgroup,
236 css);
237}
238
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800239static struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p)
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800240{
241 return container_of(task_subsys_state(p, mem_cgroup_subsys_id),
242 struct mem_cgroup, css);
243}
244
245void mm_init_cgroup(struct mm_struct *mm, struct task_struct *p)
246{
247 struct mem_cgroup *mem;
248
249 mem = mem_cgroup_from_task(p);
250 css_get(&mem->css);
251 mm->mem_cgroup = mem;
252}
253
254void mm_free_cgroup(struct mm_struct *mm)
255{
256 css_put(&mm->mem_cgroup->css);
257}
258
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800259static inline int page_cgroup_locked(struct page *page)
260{
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800261 return bit_spin_is_locked(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800262}
263
Hugh Dickins9442ec9d2008-03-04 14:29:07 -0800264static void page_assign_page_cgroup(struct page *page, struct page_cgroup *pc)
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800265{
Hugh Dickins9442ec9d2008-03-04 14:29:07 -0800266 VM_BUG_ON(!page_cgroup_locked(page));
267 page->page_cgroup = ((unsigned long)pc | PAGE_CGROUP_LOCK);
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800268}
269
270struct page_cgroup *page_get_page_cgroup(struct page *page)
271{
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800272 return (struct page_cgroup *) (page->page_cgroup & ~PAGE_CGROUP_LOCK);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800273}
274
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800275static void lock_page_cgroup(struct page *page)
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800276{
277 bit_spin_lock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800278}
279
Hugh Dickins2680eed2008-03-04 14:29:13 -0800280static int try_lock_page_cgroup(struct page *page)
281{
282 return bit_spin_trylock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
283}
284
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800285static void unlock_page_cgroup(struct page *page)
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800286{
287 bit_spin_unlock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
288}
289
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800290static void __mem_cgroup_remove_list(struct page_cgroup *pc)
291{
292 int from = pc->flags & PAGE_CGROUP_FLAG_ACTIVE;
293 struct mem_cgroup_per_zone *mz = page_cgroup_zoneinfo(pc);
294
295 if (from)
296 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) -= 1;
297 else
298 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) -= 1;
299
300 mem_cgroup_charge_statistics(pc->mem_cgroup, pc->flags, false);
301 list_del_init(&pc->lru);
302}
303
304static void __mem_cgroup_add_list(struct page_cgroup *pc)
305{
306 int to = pc->flags & PAGE_CGROUP_FLAG_ACTIVE;
307 struct mem_cgroup_per_zone *mz = page_cgroup_zoneinfo(pc);
308
309 if (!to) {
310 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) += 1;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800311 list_add(&pc->lru, &mz->inactive_list);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800312 } else {
313 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) += 1;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800314 list_add(&pc->lru, &mz->active_list);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800315 }
316 mem_cgroup_charge_statistics(pc->mem_cgroup, pc->flags, true);
317}
318
Balbir Singh8697d332008-02-07 00:13:59 -0800319static void __mem_cgroup_move_lists(struct page_cgroup *pc, bool active)
Balbir Singh66e17072008-02-07 00:13:56 -0800320{
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800321 int from = pc->flags & PAGE_CGROUP_FLAG_ACTIVE;
322 struct mem_cgroup_per_zone *mz = page_cgroup_zoneinfo(pc);
323
324 if (from)
325 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) -= 1;
326 else
327 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) -= 1;
328
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800329 if (active) {
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800330 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) += 1;
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800331 pc->flags |= PAGE_CGROUP_FLAG_ACTIVE;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800332 list_move(&pc->lru, &mz->active_list);
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800333 } else {
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800334 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) += 1;
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800335 pc->flags &= ~PAGE_CGROUP_FLAG_ACTIVE;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800336 list_move(&pc->lru, &mz->inactive_list);
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800337 }
Balbir Singh66e17072008-02-07 00:13:56 -0800338}
339
David Rientjes4c4a2212008-02-07 00:14:06 -0800340int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem)
341{
342 int ret;
343
344 task_lock(task);
Hugh Dickinsbd845e32008-03-04 14:29:01 -0800345 ret = task->mm && mm_match_cgroup(task->mm, mem);
David Rientjes4c4a2212008-02-07 00:14:06 -0800346 task_unlock(task);
347 return ret;
348}
349
Balbir Singh66e17072008-02-07 00:13:56 -0800350/*
351 * This routine assumes that the appropriate zone's lru lock is already held
352 */
Hugh Dickins427d5412008-03-04 14:29:03 -0800353void mem_cgroup_move_lists(struct page *page, bool active)
Balbir Singh66e17072008-02-07 00:13:56 -0800354{
Hugh Dickins427d5412008-03-04 14:29:03 -0800355 struct page_cgroup *pc;
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800356 struct mem_cgroup_per_zone *mz;
357 unsigned long flags;
358
Hugh Dickins2680eed2008-03-04 14:29:13 -0800359 /*
360 * We cannot lock_page_cgroup while holding zone's lru_lock,
361 * because other holders of lock_page_cgroup can be interrupted
362 * with an attempt to rotate_reclaimable_page. But we cannot
363 * safely get to page_cgroup without it, so just try_lock it:
364 * mem_cgroup_isolate_pages allows for page left on wrong list.
365 */
366 if (!try_lock_page_cgroup(page))
Balbir Singh66e17072008-02-07 00:13:56 -0800367 return;
368
Hugh Dickins2680eed2008-03-04 14:29:13 -0800369 pc = page_get_page_cgroup(page);
370 if (pc) {
Hugh Dickins2680eed2008-03-04 14:29:13 -0800371 mz = page_cgroup_zoneinfo(pc);
Hugh Dickins2680eed2008-03-04 14:29:13 -0800372 spin_lock_irqsave(&mz->lru_lock, flags);
Hirokazu Takahashi9b3c0a02008-03-04 14:29:15 -0800373 __mem_cgroup_move_lists(pc, active);
Hugh Dickins2680eed2008-03-04 14:29:13 -0800374 spin_unlock_irqrestore(&mz->lru_lock, flags);
Hirokazu Takahashi9b3c0a02008-03-04 14:29:15 -0800375 }
376 unlock_page_cgroup(page);
Balbir Singh66e17072008-02-07 00:13:56 -0800377}
378
KAMEZAWA Hiroyuki58ae83d2008-02-07 00:14:32 -0800379/*
380 * Calculate mapped_ratio under memory controller. This will be used in
381 * vmscan.c for deteremining we have to reclaim mapped pages.
382 */
383int mem_cgroup_calc_mapped_ratio(struct mem_cgroup *mem)
384{
385 long total, rss;
386
387 /*
388 * usage is recorded in bytes. But, here, we assume the number of
389 * physical pages can be represented by "long" on any arch.
390 */
391 total = (long) (mem->res.usage >> PAGE_SHIFT) + 1L;
392 rss = (long)mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_RSS);
393 return (int)((rss * 100L) / total);
394}
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800395
KAMEZAWA Hiroyuki5932f362008-02-07 00:14:33 -0800396/*
397 * This function is called from vmscan.c. In page reclaiming loop. balance
398 * between active and inactive list is calculated. For memory controller
399 * page reclaiming, we should use using mem_cgroup's imbalance rather than
400 * zone's global lru imbalance.
401 */
402long mem_cgroup_reclaim_imbalance(struct mem_cgroup *mem)
403{
404 unsigned long active, inactive;
405 /* active and inactive are the number of pages. 'long' is ok.*/
406 active = mem_cgroup_get_all_zonestat(mem, MEM_CGROUP_ZSTAT_ACTIVE);
407 inactive = mem_cgroup_get_all_zonestat(mem, MEM_CGROUP_ZSTAT_INACTIVE);
408 return (long) (active / (inactive + 1));
409}
KAMEZAWA Hiroyuki58ae83d2008-02-07 00:14:32 -0800410
KAMEZAWA Hiroyuki6c48a1d2008-02-07 00:14:34 -0800411/*
412 * prev_priority control...this will be used in memory reclaim path.
413 */
414int mem_cgroup_get_reclaim_priority(struct mem_cgroup *mem)
415{
416 return mem->prev_priority;
417}
418
419void mem_cgroup_note_reclaim_priority(struct mem_cgroup *mem, int priority)
420{
421 if (priority < mem->prev_priority)
422 mem->prev_priority = priority;
423}
424
425void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, int priority)
426{
427 mem->prev_priority = priority;
428}
429
KAMEZAWA Hiroyukicc381082008-02-07 00:14:35 -0800430/*
431 * Calculate # of pages to be scanned in this priority/zone.
432 * See also vmscan.c
433 *
434 * priority starts from "DEF_PRIORITY" and decremented in each loop.
435 * (see include/linux/mmzone.h)
436 */
437
438long mem_cgroup_calc_reclaim_active(struct mem_cgroup *mem,
439 struct zone *zone, int priority)
440{
441 long nr_active;
442 int nid = zone->zone_pgdat->node_id;
443 int zid = zone_idx(zone);
444 struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(mem, nid, zid);
445
446 nr_active = MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE);
447 return (nr_active >> priority);
448}
449
450long mem_cgroup_calc_reclaim_inactive(struct mem_cgroup *mem,
451 struct zone *zone, int priority)
452{
453 long nr_inactive;
454 int nid = zone->zone_pgdat->node_id;
455 int zid = zone_idx(zone);
456 struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(mem, nid, zid);
457
458 nr_inactive = MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE);
KAMEZAWA Hiroyukicc381082008-02-07 00:14:35 -0800459 return (nr_inactive >> priority);
460}
461
Balbir Singh66e17072008-02-07 00:13:56 -0800462unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
463 struct list_head *dst,
464 unsigned long *scanned, int order,
465 int mode, struct zone *z,
466 struct mem_cgroup *mem_cont,
467 int active)
468{
469 unsigned long nr_taken = 0;
470 struct page *page;
471 unsigned long scan;
472 LIST_HEAD(pc_list);
473 struct list_head *src;
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800474 struct page_cgroup *pc, *tmp;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800475 int nid = z->zone_pgdat->node_id;
476 int zid = zone_idx(z);
477 struct mem_cgroup_per_zone *mz;
Balbir Singh66e17072008-02-07 00:13:56 -0800478
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800479 mz = mem_cgroup_zoneinfo(mem_cont, nid, zid);
Balbir Singh66e17072008-02-07 00:13:56 -0800480 if (active)
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800481 src = &mz->active_list;
Balbir Singh66e17072008-02-07 00:13:56 -0800482 else
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800483 src = &mz->inactive_list;
484
Balbir Singh66e17072008-02-07 00:13:56 -0800485
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800486 spin_lock(&mz->lru_lock);
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800487 scan = 0;
488 list_for_each_entry_safe_reverse(pc, tmp, src, lru) {
Hugh Dickins436c65412008-02-07 00:14:12 -0800489 if (scan >= nr_to_scan)
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800490 break;
Balbir Singh66e17072008-02-07 00:13:56 -0800491 page = pc->page;
Balbir Singh66e17072008-02-07 00:13:56 -0800492
Hugh Dickins436c65412008-02-07 00:14:12 -0800493 if (unlikely(!PageLRU(page)))
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800494 continue;
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800495
Balbir Singh66e17072008-02-07 00:13:56 -0800496 if (PageActive(page) && !active) {
497 __mem_cgroup_move_lists(pc, true);
Balbir Singh66e17072008-02-07 00:13:56 -0800498 continue;
499 }
500 if (!PageActive(page) && active) {
501 __mem_cgroup_move_lists(pc, false);
Balbir Singh66e17072008-02-07 00:13:56 -0800502 continue;
503 }
504
Hugh Dickins436c65412008-02-07 00:14:12 -0800505 scan++;
506 list_move(&pc->lru, &pc_list);
Balbir Singh66e17072008-02-07 00:13:56 -0800507
508 if (__isolate_lru_page(page, mode) == 0) {
509 list_move(&page->lru, dst);
510 nr_taken++;
511 }
512 }
513
514 list_splice(&pc_list, src);
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800515 spin_unlock(&mz->lru_lock);
Balbir Singh66e17072008-02-07 00:13:56 -0800516
517 *scanned = scan;
518 return nr_taken;
519}
520
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800521/*
522 * Charge the memory controller for page usage.
523 * Return
524 * 0 if the charge was successful
525 * < 0 if the cgroup is over its limit
526 */
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800527static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
528 gfp_t gfp_mask, enum charge_type ctype)
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800529{
530 struct mem_cgroup *mem;
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800531 struct page_cgroup *pc;
Balbir Singh66e17072008-02-07 00:13:56 -0800532 unsigned long flags;
533 unsigned long nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800534 struct mem_cgroup_per_zone *mz;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800535
536 /*
537 * Should page_cgroup's go to their own slab?
538 * One could optimize the performance of the charging routine
539 * by saving a bit in the page_flags and using it as a lock
540 * to see if the cgroup page already has a page_cgroup associated
541 * with it
542 */
Balbir Singh66e17072008-02-07 00:13:56 -0800543retry:
Hugh Dickins7e924aa2008-03-04 14:29:08 -0800544 lock_page_cgroup(page);
545 pc = page_get_page_cgroup(page);
546 /*
547 * The page_cgroup exists and
548 * the page has already been accounted.
549 */
550 if (pc) {
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800551 VM_BUG_ON(pc->page != page);
552 VM_BUG_ON(pc->ref_cnt <= 0);
553
554 pc->ref_cnt++;
555 unlock_page_cgroup(page);
556 goto done;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800557 }
Hugh Dickins7e924aa2008-03-04 14:29:08 -0800558 unlock_page_cgroup(page);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800559
Balbir Singhe1a1cd52008-02-07 00:14:02 -0800560 pc = kzalloc(sizeof(struct page_cgroup), gfp_mask);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800561 if (pc == NULL)
562 goto err;
563
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800564 /*
Hugh Dickins3be91272008-02-07 00:14:19 -0800565 * We always charge the cgroup the mm_struct belongs to.
566 * The mm_struct's mem_cgroup changes on task migration if the
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800567 * thread group leader migrates. It's possible that mm is not
568 * set, if so charge the init_mm (happens for pagecache usage).
569 */
570 if (!mm)
571 mm = &init_mm;
572
Hugh Dickins3be91272008-02-07 00:14:19 -0800573 rcu_read_lock();
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800574 mem = rcu_dereference(mm->mem_cgroup);
575 /*
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800576 * For every charge from the cgroup, increment reference count
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800577 */
578 css_get(&mem->css);
579 rcu_read_unlock();
580
Balbir Singh0eea1032008-02-07 00:13:57 -0800581 while (res_counter_charge(&mem->res, PAGE_SIZE)) {
Hugh Dickins3be91272008-02-07 00:14:19 -0800582 if (!(gfp_mask & __GFP_WAIT))
583 goto out;
Balbir Singhe1a1cd52008-02-07 00:14:02 -0800584
585 if (try_to_free_mem_cgroup_pages(mem, gfp_mask))
Balbir Singh66e17072008-02-07 00:13:56 -0800586 continue;
587
588 /*
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800589 * try_to_free_mem_cgroup_pages() might not give us a full
590 * picture of reclaim. Some pages are reclaimed and might be
591 * moved to swap cache or just unmapped from the cgroup.
592 * Check the limit again to see if the reclaim reduced the
593 * current usage of the cgroup before giving up
594 */
Balbir Singh66e17072008-02-07 00:13:56 -0800595 if (res_counter_check_under_limit(&mem->res))
596 continue;
Hugh Dickins3be91272008-02-07 00:14:19 -0800597
598 if (!nr_retries--) {
599 mem_cgroup_out_of_memory(mem, gfp_mask);
600 goto out;
Balbir Singh66e17072008-02-07 00:13:56 -0800601 }
Hugh Dickins3be91272008-02-07 00:14:19 -0800602 congestion_wait(WRITE, HZ/10);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800603 }
604
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800605 pc->ref_cnt = 1;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800606 pc->mem_cgroup = mem;
607 pc->page = page;
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800608 pc->flags = PAGE_CGROUP_FLAG_ACTIVE;
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800609 if (ctype == MEM_CGROUP_CHARGE_TYPE_CACHE)
610 pc->flags |= PAGE_CGROUP_FLAG_CACHE;
Hugh Dickins3be91272008-02-07 00:14:19 -0800611
Hugh Dickins7e924aa2008-03-04 14:29:08 -0800612 lock_page_cgroup(page);
613 if (page_get_page_cgroup(page)) {
614 unlock_page_cgroup(page);
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800615 /*
Hugh Dickins3be91272008-02-07 00:14:19 -0800616 * Another charge has been added to this page already.
617 * We take lock_page_cgroup(page) again and read
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800618 * page->cgroup, increment refcnt.... just retry is OK.
619 */
620 res_counter_uncharge(&mem->res, PAGE_SIZE);
621 css_put(&mem->css);
622 kfree(pc);
623 goto retry;
624 }
Hugh Dickins7e924aa2008-03-04 14:29:08 -0800625 page_assign_page_cgroup(page, pc);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800626
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800627 mz = page_cgroup_zoneinfo(pc);
628 spin_lock_irqsave(&mz->lru_lock, flags);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800629 __mem_cgroup_add_list(pc);
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800630 spin_unlock_irqrestore(&mz->lru_lock, flags);
Balbir Singh66e17072008-02-07 00:13:56 -0800631
Hugh Dickinsfb59e9f2008-03-04 14:29:16 -0800632 unlock_page_cgroup(page);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800633done:
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800634 return 0;
Hugh Dickins3be91272008-02-07 00:14:19 -0800635out:
636 css_put(&mem->css);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800637 kfree(pc);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800638err:
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800639 return -ENOMEM;
640}
641
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800642int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800643{
644 return mem_cgroup_charge_common(page, mm, gfp_mask,
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800645 MEM_CGROUP_CHARGE_TYPE_MAPPED);
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800646}
647
Balbir Singhe1a1cd52008-02-07 00:14:02 -0800648int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
649 gfp_t gfp_mask)
Balbir Singh8697d332008-02-07 00:13:59 -0800650{
Balbir Singh8697d332008-02-07 00:13:59 -0800651 if (!mm)
652 mm = &init_mm;
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800653 return mem_cgroup_charge_common(page, mm, gfp_mask,
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800654 MEM_CGROUP_CHARGE_TYPE_CACHE);
Balbir Singh8697d332008-02-07 00:13:59 -0800655}
656
657/*
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800658 * Uncharging is always a welcome operation, we never complain, simply
Hugh Dickins82895462008-03-04 14:29:08 -0800659 * uncharge.
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800660 */
Hugh Dickins82895462008-03-04 14:29:08 -0800661void mem_cgroup_uncharge_page(struct page *page)
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800662{
Hugh Dickins82895462008-03-04 14:29:08 -0800663 struct page_cgroup *pc;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800664 struct mem_cgroup *mem;
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800665 struct mem_cgroup_per_zone *mz;
Balbir Singh66e17072008-02-07 00:13:56 -0800666 unsigned long flags;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800667
Balbir Singh8697d332008-02-07 00:13:59 -0800668 /*
Balbir Singh3c541e12008-02-07 00:14:41 -0800669 * Check if our page_cgroup is valid
Balbir Singh8697d332008-02-07 00:13:59 -0800670 */
Hugh Dickins82895462008-03-04 14:29:08 -0800671 lock_page_cgroup(page);
672 pc = page_get_page_cgroup(page);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800673 if (!pc)
Hugh Dickins82895462008-03-04 14:29:08 -0800674 goto unlock;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800675
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800676 VM_BUG_ON(pc->page != page);
677 VM_BUG_ON(pc->ref_cnt <= 0);
678
679 if (--(pc->ref_cnt) == 0) {
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800680 mz = page_cgroup_zoneinfo(pc);
681 spin_lock_irqsave(&mz->lru_lock, flags);
682 __mem_cgroup_remove_list(pc);
683 spin_unlock_irqrestore(&mz->lru_lock, flags);
684
Hugh Dickinsfb59e9f2008-03-04 14:29:16 -0800685 page_assign_page_cgroup(page, NULL);
686 unlock_page_cgroup(page);
687
Hugh Dickins6d48ff82008-03-04 14:29:12 -0800688 mem = pc->mem_cgroup;
689 res_counter_uncharge(&mem->res, PAGE_SIZE);
690 css_put(&mem->css);
691
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800692 kfree(pc);
693 return;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800694 }
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800695
Hugh Dickins82895462008-03-04 14:29:08 -0800696unlock:
Balbir Singh3c541e12008-02-07 00:14:41 -0800697 unlock_page_cgroup(page);
698}
699
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800700/*
701 * Returns non-zero if a page (under migration) has valid page_cgroup member.
702 * Refcnt of page_cgroup is incremented.
703 */
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800704int mem_cgroup_prepare_migration(struct page *page)
705{
706 struct page_cgroup *pc;
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800707
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800708 lock_page_cgroup(page);
709 pc = page_get_page_cgroup(page);
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800710 if (pc)
711 pc->ref_cnt++;
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800712 unlock_page_cgroup(page);
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800713 return pc != NULL;
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800714}
715
716void mem_cgroup_end_migration(struct page *page)
717{
Hugh Dickins82895462008-03-04 14:29:08 -0800718 mem_cgroup_uncharge_page(page);
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800719}
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800720
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800721/*
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800722 * We know both *page* and *newpage* are now not-on-LRU and PG_locked.
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800723 * And no race with uncharge() routines because page_cgroup for *page*
724 * has extra one reference by mem_cgroup_prepare_migration.
725 */
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800726void mem_cgroup_page_migration(struct page *page, struct page *newpage)
727{
728 struct page_cgroup *pc;
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800729 struct mem_cgroup_per_zone *mz;
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800730 unsigned long flags;
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800731
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800732 lock_page_cgroup(page);
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800733 pc = page_get_page_cgroup(page);
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800734 if (!pc) {
735 unlock_page_cgroup(page);
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800736 return;
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800737 }
738
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800739 mz = page_cgroup_zoneinfo(pc);
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800740 spin_lock_irqsave(&mz->lru_lock, flags);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800741 __mem_cgroup_remove_list(pc);
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800742 spin_unlock_irqrestore(&mz->lru_lock, flags);
743
Hugh Dickinsfb59e9f2008-03-04 14:29:16 -0800744 page_assign_page_cgroup(page, NULL);
745 unlock_page_cgroup(page);
746
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800747 pc->page = newpage;
748 lock_page_cgroup(newpage);
749 page_assign_page_cgroup(newpage, pc);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800750
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800751 mz = page_cgroup_zoneinfo(pc);
752 spin_lock_irqsave(&mz->lru_lock, flags);
753 __mem_cgroup_add_list(pc);
754 spin_unlock_irqrestore(&mz->lru_lock, flags);
Hugh Dickinsfb59e9f2008-03-04 14:29:16 -0800755
756 unlock_page_cgroup(newpage);
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800757}
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800758
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800759/*
760 * This routine traverse page_cgroup in given list and drop them all.
761 * This routine ignores page_cgroup->ref_cnt.
762 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
763 */
764#define FORCE_UNCHARGE_BATCH (128)
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800765static void mem_cgroup_force_empty_list(struct mem_cgroup *mem,
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800766 struct mem_cgroup_per_zone *mz,
767 int active)
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800768{
769 struct page_cgroup *pc;
770 struct page *page;
Hirokazu Takahashi9b3c0a02008-03-04 14:29:15 -0800771 int count = FORCE_UNCHARGE_BATCH;
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800772 unsigned long flags;
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800773 struct list_head *list;
774
775 if (active)
776 list = &mz->active_list;
777 else
778 list = &mz->inactive_list;
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800779
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800780 spin_lock_irqsave(&mz->lru_lock, flags);
Hirokazu Takahashi9b3c0a02008-03-04 14:29:15 -0800781 while (!list_empty(list)) {
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800782 pc = list_entry(list->prev, struct page_cgroup, lru);
783 page = pc->page;
Hirokazu Takahashi9b3c0a02008-03-04 14:29:15 -0800784 get_page(page);
785 spin_unlock_irqrestore(&mz->lru_lock, flags);
786 mem_cgroup_uncharge_page(page);
787 put_page(page);
788 if (--count <= 0) {
789 count = FORCE_UNCHARGE_BATCH;
790 cond_resched();
Hugh Dickinsb9c565d2008-03-04 14:29:11 -0800791 }
Hirokazu Takahashi9b3c0a02008-03-04 14:29:15 -0800792 spin_lock_irqsave(&mz->lru_lock, flags);
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800793 }
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800794 spin_unlock_irqrestore(&mz->lru_lock, flags);
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800795}
796
797/*
798 * make mem_cgroup's charge to be 0 if there is no task.
799 * This enables deleting this mem_cgroup.
800 */
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800801static int mem_cgroup_force_empty(struct mem_cgroup *mem)
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800802{
803 int ret = -EBUSY;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800804 int node, zid;
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800805
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800806 css_get(&mem->css);
807 /*
808 * page reclaim code (kswapd etc..) will move pages between
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800809 * active_list <-> inactive_list while we don't take a lock.
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800810 * So, we have to do loop here until all lists are empty.
811 */
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800812 while (mem->res.usage > 0) {
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800813 if (atomic_read(&mem->css.cgroup->count) > 0)
814 goto out;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800815 for_each_node_state(node, N_POSSIBLE)
816 for (zid = 0; zid < MAX_NR_ZONES; zid++) {
817 struct mem_cgroup_per_zone *mz;
818 mz = mem_cgroup_zoneinfo(mem, node, zid);
819 /* drop all page_cgroup in active_list */
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800820 mem_cgroup_force_empty_list(mem, mz, 1);
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800821 /* drop all page_cgroup in inactive_list */
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800822 mem_cgroup_force_empty_list(mem, mz, 0);
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800823 }
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800824 }
825 ret = 0;
826out:
827 css_put(&mem->css);
828 return ret;
829}
830
Hugh Dickinsd5b69e32008-03-04 14:29:10 -0800831static int mem_cgroup_write_strategy(char *buf, unsigned long long *tmp)
Balbir Singh0eea1032008-02-07 00:13:57 -0800832{
833 *tmp = memparse(buf, &buf);
834 if (*buf != '\0')
835 return -EINVAL;
836
837 /*
838 * Round up the value to the closest page size
839 */
840 *tmp = ((*tmp + PAGE_SIZE - 1) >> PAGE_SHIFT) << PAGE_SHIFT;
841 return 0;
842}
843
844static ssize_t mem_cgroup_read(struct cgroup *cont,
845 struct cftype *cft, struct file *file,
846 char __user *userbuf, size_t nbytes, loff_t *ppos)
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800847{
848 return res_counter_read(&mem_cgroup_from_cont(cont)->res,
Balbir Singh0eea1032008-02-07 00:13:57 -0800849 cft->private, userbuf, nbytes, ppos,
850 NULL);
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800851}
852
853static ssize_t mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
854 struct file *file, const char __user *userbuf,
855 size_t nbytes, loff_t *ppos)
856{
857 return res_counter_write(&mem_cgroup_from_cont(cont)->res,
Balbir Singh0eea1032008-02-07 00:13:57 -0800858 cft->private, userbuf, nbytes, ppos,
859 mem_cgroup_write_strategy);
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800860}
861
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800862static ssize_t mem_force_empty_write(struct cgroup *cont,
863 struct cftype *cft, struct file *file,
864 const char __user *userbuf,
865 size_t nbytes, loff_t *ppos)
866{
867 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
Hugh Dickins8869b8f2008-03-04 14:29:09 -0800868 int ret = mem_cgroup_force_empty(mem);
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800869 if (!ret)
870 ret = nbytes;
871 return ret;
872}
873
874/*
875 * Note: This should be removed if cgroup supports write-only file.
876 */
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800877static ssize_t mem_force_empty_read(struct cgroup *cont,
878 struct cftype *cft,
879 struct file *file, char __user *userbuf,
880 size_t nbytes, loff_t *ppos)
881{
882 return -EINVAL;
883}
884
KAMEZAWA Hiroyukid2ceb9b2008-02-07 00:14:25 -0800885static const struct mem_cgroup_stat_desc {
886 const char *msg;
887 u64 unit;
888} mem_cgroup_stat_desc[] = {
889 [MEM_CGROUP_STAT_CACHE] = { "cache", PAGE_SIZE, },
890 [MEM_CGROUP_STAT_RSS] = { "rss", PAGE_SIZE, },
891};
892
893static int mem_control_stat_show(struct seq_file *m, void *arg)
894{
895 struct cgroup *cont = m->private;
896 struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont);
897 struct mem_cgroup_stat *stat = &mem_cont->stat;
898 int i;
899
900 for (i = 0; i < ARRAY_SIZE(stat->cpustat[0].count); i++) {
901 s64 val;
902
903 val = mem_cgroup_read_stat(stat, i);
904 val *= mem_cgroup_stat_desc[i].unit;
905 seq_printf(m, "%s %lld\n", mem_cgroup_stat_desc[i].msg,
906 (long long)val);
907 }
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800908 /* showing # of active pages */
909 {
910 unsigned long active, inactive;
911
912 inactive = mem_cgroup_get_all_zonestat(mem_cont,
913 MEM_CGROUP_ZSTAT_INACTIVE);
914 active = mem_cgroup_get_all_zonestat(mem_cont,
915 MEM_CGROUP_ZSTAT_ACTIVE);
916 seq_printf(m, "active %ld\n", (active) * PAGE_SIZE);
917 seq_printf(m, "inactive %ld\n", (inactive) * PAGE_SIZE);
918 }
KAMEZAWA Hiroyukid2ceb9b2008-02-07 00:14:25 -0800919 return 0;
920}
921
922static const struct file_operations mem_control_stat_file_operations = {
923 .read = seq_read,
924 .llseek = seq_lseek,
925 .release = single_release,
926};
927
928static int mem_control_stat_open(struct inode *unused, struct file *file)
929{
930 /* XXX __d_cont */
931 struct cgroup *cont = file->f_dentry->d_parent->d_fsdata;
932
933 file->f_op = &mem_control_stat_file_operations;
934 return single_open(file, mem_control_stat_show, cont);
935}
936
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800937static struct cftype mem_cgroup_files[] = {
938 {
Balbir Singh0eea1032008-02-07 00:13:57 -0800939 .name = "usage_in_bytes",
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800940 .private = RES_USAGE,
941 .read = mem_cgroup_read,
942 },
943 {
Balbir Singh0eea1032008-02-07 00:13:57 -0800944 .name = "limit_in_bytes",
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800945 .private = RES_LIMIT,
946 .write = mem_cgroup_write,
947 .read = mem_cgroup_read,
948 },
949 {
950 .name = "failcnt",
951 .private = RES_FAILCNT,
952 .read = mem_cgroup_read,
953 },
Balbir Singh8697d332008-02-07 00:13:59 -0800954 {
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800955 .name = "force_empty",
956 .write = mem_force_empty_write,
957 .read = mem_force_empty_read,
958 },
KAMEZAWA Hiroyukid2ceb9b2008-02-07 00:14:25 -0800959 {
960 .name = "stat",
961 .open = mem_control_stat_open,
962 },
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800963};
964
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800965static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
966{
967 struct mem_cgroup_per_node *pn;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800968 struct mem_cgroup_per_zone *mz;
969 int zone;
970 /*
971 * This routine is called against possible nodes.
972 * But it's BUG to call kmalloc() against offline node.
973 *
974 * TODO: this routine can waste much memory for nodes which will
975 * never be onlined. It's better to use memory hotplug callback
976 * function.
977 */
978 if (node_state(node, N_HIGH_MEMORY))
979 pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, node);
980 else
981 pn = kmalloc(sizeof(*pn), GFP_KERNEL);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800982 if (!pn)
983 return 1;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800984
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800985 mem->info.nodeinfo[node] = pn;
986 memset(pn, 0, sizeof(*pn));
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800987
988 for (zone = 0; zone < MAX_NR_ZONES; zone++) {
989 mz = &pn->zoneinfo[zone];
990 INIT_LIST_HEAD(&mz->active_list);
991 INIT_LIST_HEAD(&mz->inactive_list);
KAMEZAWA Hiroyuki072c56c2008-02-07 00:14:39 -0800992 spin_lock_init(&mz->lru_lock);
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800993 }
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800994 return 0;
995}
996
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800997static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
998{
999 kfree(mem->info.nodeinfo[node]);
1000}
1001
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001002static struct cgroup_subsys_state *
1003mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
1004{
1005 struct mem_cgroup *mem;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001006 int node;
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001007
Pavel Emelianov78fb7462008-02-07 00:13:51 -08001008 if (unlikely((cont->parent) == NULL)) {
1009 mem = &init_mem_cgroup;
1010 init_mm.mem_cgroup = mem;
1011 } else
1012 mem = kzalloc(sizeof(struct mem_cgroup), GFP_KERNEL);
1013
1014 if (mem == NULL)
Li Zefan2dda81c2008-02-23 15:24:14 -08001015 return ERR_PTR(-ENOMEM);
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001016
1017 res_counter_init(&mem->res);
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001018
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001019 memset(&mem->info, 0, sizeof(mem->info));
1020
1021 for_each_node_state(node, N_POSSIBLE)
1022 if (alloc_mem_cgroup_per_zone_info(mem, node))
1023 goto free_out;
1024
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001025 return &mem->css;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001026free_out:
1027 for_each_node_state(node, N_POSSIBLE)
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001028 free_mem_cgroup_per_zone_info(mem, node);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001029 if (cont->parent != NULL)
1030 kfree(mem);
Li Zefan2dda81c2008-02-23 15:24:14 -08001031 return ERR_PTR(-ENOMEM);
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001032}
1033
KAMEZAWA Hiroyukidf878fb2008-02-07 00:14:28 -08001034static void mem_cgroup_pre_destroy(struct cgroup_subsys *ss,
1035 struct cgroup *cont)
1036{
1037 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
1038 mem_cgroup_force_empty(mem);
1039}
1040
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001041static void mem_cgroup_destroy(struct cgroup_subsys *ss,
1042 struct cgroup *cont)
1043{
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001044 int node;
1045 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
1046
1047 for_each_node_state(node, N_POSSIBLE)
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001048 free_mem_cgroup_per_zone_info(mem, node);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001049
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001050 kfree(mem_cgroup_from_cont(cont));
1051}
1052
1053static int mem_cgroup_populate(struct cgroup_subsys *ss,
1054 struct cgroup *cont)
1055{
1056 return cgroup_add_files(cont, ss, mem_cgroup_files,
1057 ARRAY_SIZE(mem_cgroup_files));
1058}
1059
Balbir Singh67e465a2008-02-07 00:13:54 -08001060static void mem_cgroup_move_task(struct cgroup_subsys *ss,
1061 struct cgroup *cont,
1062 struct cgroup *old_cont,
1063 struct task_struct *p)
1064{
1065 struct mm_struct *mm;
1066 struct mem_cgroup *mem, *old_mem;
1067
1068 mm = get_task_mm(p);
1069 if (mm == NULL)
1070 return;
1071
1072 mem = mem_cgroup_from_cont(cont);
1073 old_mem = mem_cgroup_from_cont(old_cont);
1074
1075 if (mem == old_mem)
1076 goto out;
1077
1078 /*
1079 * Only thread group leaders are allowed to migrate, the mm_struct is
1080 * in effect owned by the leader
1081 */
Pavel Emelyanov52ea27e2008-03-19 17:00:45 -07001082 if (!thread_group_leader(p))
Balbir Singh67e465a2008-02-07 00:13:54 -08001083 goto out;
1084
1085 css_get(&mem->css);
1086 rcu_assign_pointer(mm->mem_cgroup, mem);
1087 css_put(&old_mem->css);
1088
1089out:
1090 mmput(mm);
Balbir Singh67e465a2008-02-07 00:13:54 -08001091}
1092
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001093struct cgroup_subsys mem_cgroup_subsys = {
1094 .name = "memory",
1095 .subsys_id = mem_cgroup_subsys_id,
1096 .create = mem_cgroup_create,
KAMEZAWA Hiroyukidf878fb2008-02-07 00:14:28 -08001097 .pre_destroy = mem_cgroup_pre_destroy,
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001098 .destroy = mem_cgroup_destroy,
1099 .populate = mem_cgroup_populate,
Balbir Singh67e465a2008-02-07 00:13:54 -08001100 .attach = mem_cgroup_move_task,
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001101 .early_init = 0,
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001102};