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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 Hiroyuki072c56c12008-02-07 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 Hiroyuki072c56c12008-02-07 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};
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 Hiroyukic01495302008-02-07 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;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800368 list_add(&pc->lru, &mz->inactive_list);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800369 } else {
370 MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) += 1;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800371 list_add(&pc->lru, &mz->active_list);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800372 }
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;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800389 list_move(&pc->lru, &mz->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;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800393 list_move(&pc->lru, &mz->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);
David Rientjes60c12b12008-02-09 00:10:15 -0800402 ret = task->mm && vm_match_cgroup(task->mm, mem);
David Rientjes4c4a2212008-02-07 00:14:06 -0800403 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{
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800412 struct mem_cgroup_per_zone *mz;
413 unsigned long flags;
414
Balbir Singh66e17072008-02-07 00:13:56 -0800415 if (!pc)
416 return;
417
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800418 mz = page_cgroup_zoneinfo(pc);
419 spin_lock_irqsave(&mz->lru_lock, flags);
Balbir Singh66e17072008-02-07 00:13:56 -0800420 __mem_cgroup_move_lists(pc, active);
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800421 spin_unlock_irqrestore(&mz->lru_lock, flags);
Balbir Singh66e17072008-02-07 00:13:56 -0800422}
423
KAMEZAWA Hiroyuki58ae83d2008-02-07 00:14:32 -0800424/*
425 * Calculate mapped_ratio under memory controller. This will be used in
426 * vmscan.c for deteremining we have to reclaim mapped pages.
427 */
428int mem_cgroup_calc_mapped_ratio(struct mem_cgroup *mem)
429{
430 long total, rss;
431
432 /*
433 * usage is recorded in bytes. But, here, we assume the number of
434 * physical pages can be represented by "long" on any arch.
435 */
436 total = (long) (mem->res.usage >> PAGE_SHIFT) + 1L;
437 rss = (long)mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_RSS);
438 return (int)((rss * 100L) / total);
439}
KAMEZAWA Hiroyuki5932f362008-02-07 00:14:33 -0800440/*
441 * This function is called from vmscan.c. In page reclaiming loop. balance
442 * between active and inactive list is calculated. For memory controller
443 * page reclaiming, we should use using mem_cgroup's imbalance rather than
444 * zone's global lru imbalance.
445 */
446long mem_cgroup_reclaim_imbalance(struct mem_cgroup *mem)
447{
448 unsigned long active, inactive;
449 /* active and inactive are the number of pages. 'long' is ok.*/
450 active = mem_cgroup_get_all_zonestat(mem, MEM_CGROUP_ZSTAT_ACTIVE);
451 inactive = mem_cgroup_get_all_zonestat(mem, MEM_CGROUP_ZSTAT_INACTIVE);
452 return (long) (active / (inactive + 1));
453}
KAMEZAWA Hiroyuki58ae83d2008-02-07 00:14:32 -0800454
KAMEZAWA Hiroyuki6c48a1d2008-02-07 00:14:34 -0800455/*
456 * prev_priority control...this will be used in memory reclaim path.
457 */
458int mem_cgroup_get_reclaim_priority(struct mem_cgroup *mem)
459{
460 return mem->prev_priority;
461}
462
463void mem_cgroup_note_reclaim_priority(struct mem_cgroup *mem, int priority)
464{
465 if (priority < mem->prev_priority)
466 mem->prev_priority = priority;
467}
468
469void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, int priority)
470{
471 mem->prev_priority = priority;
472}
473
KAMEZAWA Hiroyukicc381082008-02-07 00:14:35 -0800474/*
475 * Calculate # of pages to be scanned in this priority/zone.
476 * See also vmscan.c
477 *
478 * priority starts from "DEF_PRIORITY" and decremented in each loop.
479 * (see include/linux/mmzone.h)
480 */
481
482long mem_cgroup_calc_reclaim_active(struct mem_cgroup *mem,
483 struct zone *zone, int priority)
484{
485 long nr_active;
486 int nid = zone->zone_pgdat->node_id;
487 int zid = zone_idx(zone);
488 struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(mem, nid, zid);
489
490 nr_active = MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE);
491 return (nr_active >> priority);
492}
493
494long mem_cgroup_calc_reclaim_inactive(struct mem_cgroup *mem,
495 struct zone *zone, int priority)
496{
497 long nr_inactive;
498 int nid = zone->zone_pgdat->node_id;
499 int zid = zone_idx(zone);
500 struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(mem, nid, zid);
501
502 nr_inactive = MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE);
503
504 return (nr_inactive >> priority);
505}
506
Balbir Singh66e17072008-02-07 00:13:56 -0800507unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
508 struct list_head *dst,
509 unsigned long *scanned, int order,
510 int mode, struct zone *z,
511 struct mem_cgroup *mem_cont,
512 int active)
513{
514 unsigned long nr_taken = 0;
515 struct page *page;
516 unsigned long scan;
517 LIST_HEAD(pc_list);
518 struct list_head *src;
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800519 struct page_cgroup *pc, *tmp;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800520 int nid = z->zone_pgdat->node_id;
521 int zid = zone_idx(z);
522 struct mem_cgroup_per_zone *mz;
Balbir Singh66e17072008-02-07 00:13:56 -0800523
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800524 mz = mem_cgroup_zoneinfo(mem_cont, nid, zid);
Balbir Singh66e17072008-02-07 00:13:56 -0800525 if (active)
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800526 src = &mz->active_list;
Balbir Singh66e17072008-02-07 00:13:56 -0800527 else
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800528 src = &mz->inactive_list;
529
Balbir Singh66e17072008-02-07 00:13:56 -0800530
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800531 spin_lock(&mz->lru_lock);
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800532 scan = 0;
533 list_for_each_entry_safe_reverse(pc, tmp, src, lru) {
Hugh Dickins436c65412008-02-07 00:14:12 -0800534 if (scan >= nr_to_scan)
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800535 break;
Balbir Singh66e17072008-02-07 00:13:56 -0800536 page = pc->page;
537 VM_BUG_ON(!pc);
538
Hugh Dickins436c65412008-02-07 00:14:12 -0800539 if (unlikely(!PageLRU(page)))
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800540 continue;
KAMEZAWA Hiroyukiff7283f2008-02-07 00:14:11 -0800541
Balbir Singh66e17072008-02-07 00:13:56 -0800542 if (PageActive(page) && !active) {
543 __mem_cgroup_move_lists(pc, true);
Balbir Singh66e17072008-02-07 00:13:56 -0800544 continue;
545 }
546 if (!PageActive(page) && active) {
547 __mem_cgroup_move_lists(pc, false);
Balbir Singh66e17072008-02-07 00:13:56 -0800548 continue;
549 }
550
Hugh Dickins436c65412008-02-07 00:14:12 -0800551 scan++;
552 list_move(&pc->lru, &pc_list);
Balbir Singh66e17072008-02-07 00:13:56 -0800553
554 if (__isolate_lru_page(page, mode) == 0) {
555 list_move(&page->lru, dst);
556 nr_taken++;
557 }
558 }
559
560 list_splice(&pc_list, src);
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800561 spin_unlock(&mz->lru_lock);
Balbir Singh66e17072008-02-07 00:13:56 -0800562
563 *scanned = scan;
564 return nr_taken;
565}
566
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800567/*
568 * Charge the memory controller for page usage.
569 * Return
570 * 0 if the charge was successful
571 * < 0 if the cgroup is over its limit
572 */
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800573static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
574 gfp_t gfp_mask, enum charge_type ctype)
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800575{
576 struct mem_cgroup *mem;
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800577 struct page_cgroup *pc;
Balbir Singh66e17072008-02-07 00:13:56 -0800578 unsigned long flags;
579 unsigned long nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800580 struct mem_cgroup_per_zone *mz;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800581
582 /*
583 * Should page_cgroup's go to their own slab?
584 * One could optimize the performance of the charging routine
585 * by saving a bit in the page_flags and using it as a lock
586 * to see if the cgroup page already has a page_cgroup associated
587 * with it
588 */
Balbir Singh66e17072008-02-07 00:13:56 -0800589retry:
Hugh Dickins82369552008-02-07 00:14:22 -0800590 if (page) {
591 lock_page_cgroup(page);
592 pc = page_get_page_cgroup(page);
593 /*
594 * The page_cgroup exists and
595 * the page has already been accounted.
596 */
597 if (pc) {
598 if (unlikely(!atomic_inc_not_zero(&pc->ref_cnt))) {
599 /* this page is under being uncharged ? */
600 unlock_page_cgroup(page);
601 cpu_relax();
602 goto retry;
603 } else {
604 unlock_page_cgroup(page);
605 goto done;
606 }
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800607 }
Hugh Dickins82369552008-02-07 00:14:22 -0800608 unlock_page_cgroup(page);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800609 }
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800610
Balbir Singhe1a1cd52008-02-07 00:14:02 -0800611 pc = kzalloc(sizeof(struct page_cgroup), gfp_mask);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800612 if (pc == NULL)
613 goto err;
614
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800615 /*
Hugh Dickins3be91272008-02-07 00:14:19 -0800616 * We always charge the cgroup the mm_struct belongs to.
617 * The mm_struct's mem_cgroup changes on task migration if the
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800618 * thread group leader migrates. It's possible that mm is not
619 * set, if so charge the init_mm (happens for pagecache usage).
620 */
621 if (!mm)
622 mm = &init_mm;
623
Hugh Dickins3be91272008-02-07 00:14:19 -0800624 rcu_read_lock();
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800625 mem = rcu_dereference(mm->mem_cgroup);
626 /*
627 * For every charge from the cgroup, increment reference
628 * count
629 */
630 css_get(&mem->css);
631 rcu_read_unlock();
632
633 /*
634 * If we created the page_cgroup, we should free it on exceeding
635 * the cgroup limit.
636 */
Balbir Singh0eea1032008-02-07 00:13:57 -0800637 while (res_counter_charge(&mem->res, PAGE_SIZE)) {
Hugh Dickins3be91272008-02-07 00:14:19 -0800638 if (!(gfp_mask & __GFP_WAIT))
639 goto out;
Balbir Singhe1a1cd52008-02-07 00:14:02 -0800640
641 if (try_to_free_mem_cgroup_pages(mem, gfp_mask))
Balbir Singh66e17072008-02-07 00:13:56 -0800642 continue;
643
644 /*
645 * try_to_free_mem_cgroup_pages() might not give us a full
646 * picture of reclaim. Some pages are reclaimed and might be
647 * moved to swap cache or just unmapped from the cgroup.
648 * Check the limit again to see if the reclaim reduced the
649 * current usage of the cgroup before giving up
650 */
651 if (res_counter_check_under_limit(&mem->res))
652 continue;
Hugh Dickins3be91272008-02-07 00:14:19 -0800653
654 if (!nr_retries--) {
655 mem_cgroup_out_of_memory(mem, gfp_mask);
656 goto out;
Balbir Singh66e17072008-02-07 00:13:56 -0800657 }
Hugh Dickins3be91272008-02-07 00:14:19 -0800658 congestion_wait(WRITE, HZ/10);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800659 }
660
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800661 atomic_set(&pc->ref_cnt, 1);
662 pc->mem_cgroup = mem;
663 pc->page = page;
KAMEZAWA Hiroyuki3564c7c2008-02-07 00:14:23 -0800664 pc->flags = PAGE_CGROUP_FLAG_ACTIVE;
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800665 if (ctype == MEM_CGROUP_CHARGE_TYPE_CACHE)
666 pc->flags |= PAGE_CGROUP_FLAG_CACHE;
Hugh Dickins3be91272008-02-07 00:14:19 -0800667
Hugh Dickins82369552008-02-07 00:14:22 -0800668 if (!page || page_cgroup_assign_new_page_cgroup(page, pc)) {
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800669 /*
Hugh Dickins3be91272008-02-07 00:14:19 -0800670 * Another charge has been added to this page already.
671 * We take lock_page_cgroup(page) again and read
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800672 * page->cgroup, increment refcnt.... just retry is OK.
673 */
674 res_counter_uncharge(&mem->res, PAGE_SIZE);
675 css_put(&mem->css);
676 kfree(pc);
Hugh Dickins82369552008-02-07 00:14:22 -0800677 if (!page)
678 goto done;
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800679 goto retry;
680 }
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800681
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800682 mz = page_cgroup_zoneinfo(pc);
683 spin_lock_irqsave(&mz->lru_lock, flags);
KAMEZAWA Hiroyukid52aa412008-02-07 00:14:24 -0800684 /* Update statistics vector */
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800685 __mem_cgroup_add_list(pc);
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800686 spin_unlock_irqrestore(&mz->lru_lock, flags);
Balbir Singh66e17072008-02-07 00:13:56 -0800687
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800688done:
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800689 return 0;
Hugh Dickins3be91272008-02-07 00:14:19 -0800690out:
691 css_put(&mem->css);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800692 kfree(pc);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800693err:
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800694 return -ENOMEM;
695}
696
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800697int mem_cgroup_charge(struct page *page, struct mm_struct *mm,
698 gfp_t gfp_mask)
699{
700 return mem_cgroup_charge_common(page, mm, gfp_mask,
701 MEM_CGROUP_CHARGE_TYPE_MAPPED);
702}
703
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800704/*
Balbir Singh8697d332008-02-07 00:13:59 -0800705 * See if the cached pages should be charged at all?
706 */
Balbir Singhe1a1cd52008-02-07 00:14:02 -0800707int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
708 gfp_t gfp_mask)
Balbir Singh8697d332008-02-07 00:13:59 -0800709{
Balbir Singhac44d352008-02-07 00:14:18 -0800710 int ret = 0;
Balbir Singh8697d332008-02-07 00:13:59 -0800711 if (!mm)
712 mm = &init_mm;
713
Balbir Singh3c541e12008-02-07 00:14:41 -0800714 ret = mem_cgroup_charge_common(page, mm, gfp_mask,
KAMEZAWA Hiroyuki217bc312008-02-07 00:14:17 -0800715 MEM_CGROUP_CHARGE_TYPE_CACHE);
Balbir Singhac44d352008-02-07 00:14:18 -0800716 return ret;
Balbir Singh8697d332008-02-07 00:13:59 -0800717}
718
719/*
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800720 * Uncharging is always a welcome operation, we never complain, simply
Balbir Singh3c541e12008-02-07 00:14:41 -0800721 * uncharge. This routine should be called with lock_page_cgroup held
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800722 */
723void mem_cgroup_uncharge(struct page_cgroup *pc)
724{
725 struct mem_cgroup *mem;
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800726 struct mem_cgroup_per_zone *mz;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800727 struct page *page;
Balbir Singh66e17072008-02-07 00:13:56 -0800728 unsigned long flags;
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800729
Balbir Singh8697d332008-02-07 00:13:59 -0800730 /*
Balbir Singh3c541e12008-02-07 00:14:41 -0800731 * Check if our page_cgroup is valid
Balbir Singh8697d332008-02-07 00:13:59 -0800732 */
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800733 if (!pc)
734 return;
735
736 if (atomic_dec_and_test(&pc->ref_cnt)) {
737 page = pc->page;
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800738 mz = page_cgroup_zoneinfo(pc);
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800739 /*
740 * get page->cgroup and clear it under lock.
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800741 * force_empty can drop page->cgroup without checking refcnt.
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800742 */
Balbir Singh3c541e12008-02-07 00:14:41 -0800743 unlock_page_cgroup(page);
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800744 if (clear_page_cgroup(page, pc) == pc) {
745 mem = pc->mem_cgroup;
746 css_put(&mem->css);
747 res_counter_uncharge(&mem->res, PAGE_SIZE);
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800748 spin_lock_irqsave(&mz->lru_lock, flags);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800749 __mem_cgroup_remove_list(pc);
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800750 spin_unlock_irqrestore(&mz->lru_lock, flags);
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800751 kfree(pc);
KAMEZAWA Hiroyuki9175e032008-02-07 00:14:08 -0800752 }
Balbir Singh3c541e12008-02-07 00:14:41 -0800753 lock_page_cgroup(page);
Balbir Singh8a9f3cc2008-02-07 00:13:53 -0800754 }
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800755}
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800756
Balbir Singh3c541e12008-02-07 00:14:41 -0800757void mem_cgroup_uncharge_page(struct page *page)
758{
759 lock_page_cgroup(page);
760 mem_cgroup_uncharge(page_get_page_cgroup(page));
761 unlock_page_cgroup(page);
762}
763
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800764/*
765 * Returns non-zero if a page (under migration) has valid page_cgroup member.
766 * Refcnt of page_cgroup is incremented.
767 */
768
769int mem_cgroup_prepare_migration(struct page *page)
770{
771 struct page_cgroup *pc;
772 int ret = 0;
773 lock_page_cgroup(page);
774 pc = page_get_page_cgroup(page);
775 if (pc && atomic_inc_not_zero(&pc->ref_cnt))
776 ret = 1;
777 unlock_page_cgroup(page);
778 return ret;
779}
780
781void mem_cgroup_end_migration(struct page *page)
782{
Balbir Singh3c541e12008-02-07 00:14:41 -0800783 struct page_cgroup *pc;
784
785 lock_page_cgroup(page);
786 pc = page_get_page_cgroup(page);
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800787 mem_cgroup_uncharge(pc);
Balbir Singh3c541e12008-02-07 00:14:41 -0800788 unlock_page_cgroup(page);
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800789}
790/*
791 * We know both *page* and *newpage* are now not-on-LRU and Pg_locked.
792 * And no race with uncharge() routines because page_cgroup for *page*
793 * has extra one reference by mem_cgroup_prepare_migration.
794 */
795
796void mem_cgroup_page_migration(struct page *page, struct page *newpage)
797{
798 struct page_cgroup *pc;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800799 struct mem_cgroup *mem;
800 unsigned long flags;
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800801 struct mem_cgroup_per_zone *mz;
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800802retry:
803 pc = page_get_page_cgroup(page);
804 if (!pc)
805 return;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800806 mem = pc->mem_cgroup;
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800807 mz = page_cgroup_zoneinfo(pc);
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800808 if (clear_page_cgroup(page, pc) != pc)
809 goto retry;
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800810 spin_lock_irqsave(&mz->lru_lock, flags);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800811
812 __mem_cgroup_remove_list(pc);
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800813 spin_unlock_irqrestore(&mz->lru_lock, flags);
814
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800815 pc->page = newpage;
816 lock_page_cgroup(newpage);
817 page_assign_page_cgroup(newpage, pc);
818 unlock_page_cgroup(newpage);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800819
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800820 mz = page_cgroup_zoneinfo(pc);
821 spin_lock_irqsave(&mz->lru_lock, flags);
822 __mem_cgroup_add_list(pc);
823 spin_unlock_irqrestore(&mz->lru_lock, flags);
KAMEZAWA Hiroyukiae41be32008-02-07 00:14:10 -0800824 return;
825}
Pavel Emelianov78fb7462008-02-07 00:13:51 -0800826
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800827/*
828 * This routine traverse page_cgroup in given list and drop them all.
829 * This routine ignores page_cgroup->ref_cnt.
830 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
831 */
832#define FORCE_UNCHARGE_BATCH (128)
833static void
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800834mem_cgroup_force_empty_list(struct mem_cgroup *mem,
835 struct mem_cgroup_per_zone *mz,
836 int active)
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800837{
838 struct page_cgroup *pc;
839 struct page *page;
840 int count;
841 unsigned long flags;
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800842 struct list_head *list;
843
844 if (active)
845 list = &mz->active_list;
846 else
847 list = &mz->inactive_list;
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800848
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800849 if (list_empty(list))
850 return;
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800851retry:
852 count = FORCE_UNCHARGE_BATCH;
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800853 spin_lock_irqsave(&mz->lru_lock, flags);
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800854
855 while (--count && !list_empty(list)) {
856 pc = list_entry(list->prev, struct page_cgroup, lru);
857 page = pc->page;
858 /* Avoid race with charge */
859 atomic_set(&pc->ref_cnt, 0);
860 if (clear_page_cgroup(page, pc) == pc) {
861 css_put(&mem->css);
862 res_counter_uncharge(&mem->res, PAGE_SIZE);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800863 __mem_cgroup_remove_list(pc);
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800864 kfree(pc);
865 } else /* being uncharged ? ...do relax */
866 break;
867 }
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800868 spin_unlock_irqrestore(&mz->lru_lock, flags);
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800869 if (!list_empty(list)) {
870 cond_resched();
871 goto retry;
872 }
873 return;
874}
875
876/*
877 * make mem_cgroup's charge to be 0 if there is no task.
878 * This enables deleting this mem_cgroup.
879 */
880
881int mem_cgroup_force_empty(struct mem_cgroup *mem)
882{
883 int ret = -EBUSY;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800884 int node, zid;
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800885 css_get(&mem->css);
886 /*
887 * page reclaim code (kswapd etc..) will move pages between
888` * active_list <-> inactive_list while we don't take a lock.
889 * So, we have to do loop here until all lists are empty.
890 */
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800891 while (mem->res.usage > 0) {
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800892 if (atomic_read(&mem->css.cgroup->count) > 0)
893 goto out;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800894 for_each_node_state(node, N_POSSIBLE)
895 for (zid = 0; zid < MAX_NR_ZONES; zid++) {
896 struct mem_cgroup_per_zone *mz;
897 mz = mem_cgroup_zoneinfo(mem, node, zid);
898 /* drop all page_cgroup in active_list */
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800899 mem_cgroup_force_empty_list(mem, mz, 1);
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800900 /* drop all page_cgroup in inactive_list */
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -0800901 mem_cgroup_force_empty_list(mem, mz, 0);
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -0800902 }
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800903 }
904 ret = 0;
905out:
906 css_put(&mem->css);
907 return ret;
908}
909
910
911
Balbir Singh0eea1032008-02-07 00:13:57 -0800912int mem_cgroup_write_strategy(char *buf, unsigned long long *tmp)
913{
914 *tmp = memparse(buf, &buf);
915 if (*buf != '\0')
916 return -EINVAL;
917
918 /*
919 * Round up the value to the closest page size
920 */
921 *tmp = ((*tmp + PAGE_SIZE - 1) >> PAGE_SHIFT) << PAGE_SHIFT;
922 return 0;
923}
924
925static ssize_t mem_cgroup_read(struct cgroup *cont,
926 struct cftype *cft, struct file *file,
927 char __user *userbuf, size_t nbytes, loff_t *ppos)
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800928{
929 return res_counter_read(&mem_cgroup_from_cont(cont)->res,
Balbir Singh0eea1032008-02-07 00:13:57 -0800930 cft->private, userbuf, nbytes, ppos,
931 NULL);
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800932}
933
934static ssize_t mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
935 struct file *file, const char __user *userbuf,
936 size_t nbytes, loff_t *ppos)
937{
938 return res_counter_write(&mem_cgroup_from_cont(cont)->res,
Balbir Singh0eea1032008-02-07 00:13:57 -0800939 cft->private, userbuf, nbytes, ppos,
940 mem_cgroup_write_strategy);
Balbir Singh8cdea7c2008-02-07 00:13:50 -0800941}
942
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -0800943static ssize_t mem_force_empty_write(struct cgroup *cont,
944 struct cftype *cft, struct file *file,
945 const char __user *userbuf,
946 size_t nbytes, loff_t *ppos)
947{
948 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
949 int ret;
950 ret = mem_cgroup_force_empty(mem);
951 if (!ret)
952 ret = nbytes;
953 return ret;
954}
955
956/*
957 * Note: This should be removed if cgroup supports write-only file.
958 */
959
960static ssize_t mem_force_empty_read(struct cgroup *cont,
961 struct cftype *cft,
962 struct file *file, char __user *userbuf,
963 size_t nbytes, loff_t *ppos)
964{
965 return -EINVAL;
966}
967
968
KAMEZAWA Hiroyukid2ceb9b2008-02-07 00:14:25 -0800969static const struct mem_cgroup_stat_desc {
970 const char *msg;
971 u64 unit;
972} mem_cgroup_stat_desc[] = {
973 [MEM_CGROUP_STAT_CACHE] = { "cache", PAGE_SIZE, },
974 [MEM_CGROUP_STAT_RSS] = { "rss", PAGE_SIZE, },
975};
976
977static int mem_control_stat_show(struct seq_file *m, void *arg)
978{
979 struct cgroup *cont = m->private;
980 struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont);
981 struct mem_cgroup_stat *stat = &mem_cont->stat;
982 int i;
983
984 for (i = 0; i < ARRAY_SIZE(stat->cpustat[0].count); i++) {
985 s64 val;
986
987 val = mem_cgroup_read_stat(stat, i);
988 val *= mem_cgroup_stat_desc[i].unit;
989 seq_printf(m, "%s %lld\n", mem_cgroup_stat_desc[i].msg,
990 (long long)val);
991 }
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -0800992 /* showing # of active pages */
993 {
994 unsigned long active, inactive;
995
996 inactive = mem_cgroup_get_all_zonestat(mem_cont,
997 MEM_CGROUP_ZSTAT_INACTIVE);
998 active = mem_cgroup_get_all_zonestat(mem_cont,
999 MEM_CGROUP_ZSTAT_ACTIVE);
1000 seq_printf(m, "active %ld\n", (active) * PAGE_SIZE);
1001 seq_printf(m, "inactive %ld\n", (inactive) * PAGE_SIZE);
1002 }
KAMEZAWA Hiroyukid2ceb9b2008-02-07 00:14:25 -08001003 return 0;
1004}
1005
1006static const struct file_operations mem_control_stat_file_operations = {
1007 .read = seq_read,
1008 .llseek = seq_lseek,
1009 .release = single_release,
1010};
1011
1012static int mem_control_stat_open(struct inode *unused, struct file *file)
1013{
1014 /* XXX __d_cont */
1015 struct cgroup *cont = file->f_dentry->d_parent->d_fsdata;
1016
1017 file->f_op = &mem_control_stat_file_operations;
1018 return single_open(file, mem_control_stat_show, cont);
1019}
1020
1021
1022
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001023static struct cftype mem_cgroup_files[] = {
1024 {
Balbir Singh0eea1032008-02-07 00:13:57 -08001025 .name = "usage_in_bytes",
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001026 .private = RES_USAGE,
1027 .read = mem_cgroup_read,
1028 },
1029 {
Balbir Singh0eea1032008-02-07 00:13:57 -08001030 .name = "limit_in_bytes",
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001031 .private = RES_LIMIT,
1032 .write = mem_cgroup_write,
1033 .read = mem_cgroup_read,
1034 },
1035 {
1036 .name = "failcnt",
1037 .private = RES_FAILCNT,
1038 .read = mem_cgroup_read,
1039 },
Balbir Singh8697d332008-02-07 00:13:59 -08001040 {
KAMEZAWA Hiroyukicc847582008-02-07 00:14:16 -08001041 .name = "force_empty",
1042 .write = mem_force_empty_write,
1043 .read = mem_force_empty_read,
1044 },
KAMEZAWA Hiroyukid2ceb9b2008-02-07 00:14:25 -08001045 {
1046 .name = "stat",
1047 .open = mem_control_stat_open,
1048 },
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001049};
1050
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001051static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
1052{
1053 struct mem_cgroup_per_node *pn;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001054 struct mem_cgroup_per_zone *mz;
1055 int zone;
1056 /*
1057 * This routine is called against possible nodes.
1058 * But it's BUG to call kmalloc() against offline node.
1059 *
1060 * TODO: this routine can waste much memory for nodes which will
1061 * never be onlined. It's better to use memory hotplug callback
1062 * function.
1063 */
1064 if (node_state(node, N_HIGH_MEMORY))
1065 pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, node);
1066 else
1067 pn = kmalloc(sizeof(*pn), GFP_KERNEL);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001068 if (!pn)
1069 return 1;
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001070
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001071 mem->info.nodeinfo[node] = pn;
1072 memset(pn, 0, sizeof(*pn));
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001073
1074 for (zone = 0; zone < MAX_NR_ZONES; zone++) {
1075 mz = &pn->zoneinfo[zone];
1076 INIT_LIST_HEAD(&mz->active_list);
1077 INIT_LIST_HEAD(&mz->inactive_list);
KAMEZAWA Hiroyuki072c56c12008-02-07 00:14:39 -08001078 spin_lock_init(&mz->lru_lock);
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001079 }
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001080 return 0;
1081}
1082
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001083static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
1084{
1085 kfree(mem->info.nodeinfo[node]);
1086}
1087
1088
Pavel Emelianov78fb7462008-02-07 00:13:51 -08001089static struct mem_cgroup init_mem_cgroup;
1090
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001091static struct cgroup_subsys_state *
1092mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
1093{
1094 struct mem_cgroup *mem;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001095 int node;
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001096
Pavel Emelianov78fb7462008-02-07 00:13:51 -08001097 if (unlikely((cont->parent) == NULL)) {
1098 mem = &init_mem_cgroup;
1099 init_mm.mem_cgroup = mem;
1100 } else
1101 mem = kzalloc(sizeof(struct mem_cgroup), GFP_KERNEL);
1102
1103 if (mem == NULL)
1104 return NULL;
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001105
1106 res_counter_init(&mem->res);
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001107
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001108 memset(&mem->info, 0, sizeof(mem->info));
1109
1110 for_each_node_state(node, N_POSSIBLE)
1111 if (alloc_mem_cgroup_per_zone_info(mem, node))
1112 goto free_out;
1113
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001114 return &mem->css;
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001115free_out:
1116 for_each_node_state(node, N_POSSIBLE)
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001117 free_mem_cgroup_per_zone_info(mem, node);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001118 if (cont->parent != NULL)
1119 kfree(mem);
1120 return NULL;
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001121}
1122
KAMEZAWA Hiroyukidf878fb2008-02-07 00:14:28 -08001123static void mem_cgroup_pre_destroy(struct cgroup_subsys *ss,
1124 struct cgroup *cont)
1125{
1126 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
1127 mem_cgroup_force_empty(mem);
1128}
1129
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001130static void mem_cgroup_destroy(struct cgroup_subsys *ss,
1131 struct cgroup *cont)
1132{
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001133 int node;
1134 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
1135
1136 for_each_node_state(node, N_POSSIBLE)
KAMEZAWA Hiroyuki1ecaab22008-02-07 00:14:38 -08001137 free_mem_cgroup_per_zone_info(mem, node);
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001138
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001139 kfree(mem_cgroup_from_cont(cont));
1140}
1141
1142static int mem_cgroup_populate(struct cgroup_subsys *ss,
1143 struct cgroup *cont)
1144{
1145 return cgroup_add_files(cont, ss, mem_cgroup_files,
1146 ARRAY_SIZE(mem_cgroup_files));
1147}
1148
Balbir Singh67e465a2008-02-07 00:13:54 -08001149static void mem_cgroup_move_task(struct cgroup_subsys *ss,
1150 struct cgroup *cont,
1151 struct cgroup *old_cont,
1152 struct task_struct *p)
1153{
1154 struct mm_struct *mm;
1155 struct mem_cgroup *mem, *old_mem;
1156
1157 mm = get_task_mm(p);
1158 if (mm == NULL)
1159 return;
1160
1161 mem = mem_cgroup_from_cont(cont);
1162 old_mem = mem_cgroup_from_cont(old_cont);
1163
1164 if (mem == old_mem)
1165 goto out;
1166
1167 /*
1168 * Only thread group leaders are allowed to migrate, the mm_struct is
1169 * in effect owned by the leader
1170 */
1171 if (p->tgid != p->pid)
1172 goto out;
1173
1174 css_get(&mem->css);
1175 rcu_assign_pointer(mm->mem_cgroup, mem);
1176 css_put(&old_mem->css);
1177
1178out:
1179 mmput(mm);
1180 return;
1181}
1182
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001183struct cgroup_subsys mem_cgroup_subsys = {
1184 .name = "memory",
1185 .subsys_id = mem_cgroup_subsys_id,
1186 .create = mem_cgroup_create,
KAMEZAWA Hiroyukidf878fb2008-02-07 00:14:28 -08001187 .pre_destroy = mem_cgroup_pre_destroy,
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001188 .destroy = mem_cgroup_destroy,
1189 .populate = mem_cgroup_populate,
Balbir Singh67e465a2008-02-07 00:13:54 -08001190 .attach = mem_cgroup_move_task,
KAMEZAWA Hiroyuki6d12e2d2008-02-07 00:14:31 -08001191 .early_init = 0,
Balbir Singh8cdea7c2008-02-07 00:13:50 -08001192};