1 /* memcontrol.c - Memory Controller
3 * Copyright IBM Corporation, 2007
4 * Author Balbir Singh <balbir@linux.vnet.ibm.com>
6 * Copyright 2007 OpenVZ SWsoft Inc
7 * Author: Pavel Emelianov <xemul@openvz.org>
9 * 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.
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.
20 #include <linux/res_counter.h>
21 #include <linux/memcontrol.h>
22 #include <linux/cgroup.h>
24 #include <linux/pagemap.h>
25 #include <linux/smp.h>
26 #include <linux/page-flags.h>
27 #include <linux/backing-dev.h>
28 #include <linux/bit_spinlock.h>
29 #include <linux/rcupdate.h>
30 #include <linux/mutex.h>
31 #include <linux/slab.h>
32 #include <linux/swap.h>
33 #include <linux/spinlock.h>
35 #include <linux/seq_file.h>
36 #include <linux/vmalloc.h>
37 #include <linux/mm_inline.h>
38 #include <linux/page_cgroup.h>
41 #include <asm/uaccess.h>
43 struct cgroup_subsys mem_cgroup_subsys __read_mostly
;
44 #define MEM_CGROUP_RECLAIM_RETRIES 5
46 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
47 /* Turned on only when memory cgroup is enabled && really_do_swap_account = 0 */
48 int do_swap_account __read_mostly
;
49 static int really_do_swap_account __initdata
= 1; /* for remember boot option*/
51 #define do_swap_account (0)
56 * Statistics for memory cgroup.
58 enum mem_cgroup_stat_index
{
60 * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
62 MEM_CGROUP_STAT_CACHE
, /* # of pages charged as cache */
63 MEM_CGROUP_STAT_RSS
, /* # of pages charged as rss */
64 MEM_CGROUP_STAT_PGPGIN_COUNT
, /* # of pages paged in */
65 MEM_CGROUP_STAT_PGPGOUT_COUNT
, /* # of pages paged out */
67 MEM_CGROUP_STAT_NSTATS
,
70 struct mem_cgroup_stat_cpu
{
71 s64 count
[MEM_CGROUP_STAT_NSTATS
];
72 } ____cacheline_aligned_in_smp
;
74 struct mem_cgroup_stat
{
75 struct mem_cgroup_stat_cpu cpustat
[0];
79 * For accounting under irq disable, no need for increment preempt count.
81 static inline void __mem_cgroup_stat_add_safe(struct mem_cgroup_stat_cpu
*stat
,
82 enum mem_cgroup_stat_index idx
, int val
)
84 stat
->count
[idx
] += val
;
87 static s64
mem_cgroup_read_stat(struct mem_cgroup_stat
*stat
,
88 enum mem_cgroup_stat_index idx
)
92 for_each_possible_cpu(cpu
)
93 ret
+= stat
->cpustat
[cpu
].count
[idx
];
98 * per-zone information in memory controller.
100 struct mem_cgroup_per_zone
{
102 * spin_lock to protect the per cgroup LRU
104 struct list_head lists
[NR_LRU_LISTS
];
105 unsigned long count
[NR_LRU_LISTS
];
107 struct zone_reclaim_stat reclaim_stat
;
109 /* Macro for accessing counter */
110 #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)])
112 struct mem_cgroup_per_node
{
113 struct mem_cgroup_per_zone zoneinfo
[MAX_NR_ZONES
];
116 struct mem_cgroup_lru_info
{
117 struct mem_cgroup_per_node
*nodeinfo
[MAX_NUMNODES
];
121 * The memory controller data structure. The memory controller controls both
122 * page cache and RSS per cgroup. We would eventually like to provide
123 * statistics based on the statistics developed by Rik Van Riel for clock-pro,
124 * to help the administrator determine what knobs to tune.
126 * TODO: Add a water mark for the memory controller. Reclaim will begin when
127 * we hit the water mark. May be even add a low water mark, such that
128 * no reclaim occurs from a cgroup at it's low water mark, this is
129 * a feature that will be implemented much later in the future.
132 struct cgroup_subsys_state css
;
134 * the counter to account for memory usage
136 struct res_counter res
;
138 * the counter to account for mem+swap usage.
140 struct res_counter memsw
;
142 * Per cgroup active and inactive list, similar to the
143 * per zone LRU lists.
145 struct mem_cgroup_lru_info info
;
147 int prev_priority
; /* for recording reclaim priority */
150 * While reclaiming in a hiearchy, we cache the last child we
151 * reclaimed from. Protected by cgroup_lock()
153 struct mem_cgroup
*last_scanned_child
;
155 * Should the accounting and control be hierarchical, per subtree?
158 unsigned long last_oom_jiffies
;
162 unsigned int inactive_ratio
;
165 * statistics. This must be placed at the end of memcg.
167 struct mem_cgroup_stat stat
;
171 MEM_CGROUP_CHARGE_TYPE_CACHE
= 0,
172 MEM_CGROUP_CHARGE_TYPE_MAPPED
,
173 MEM_CGROUP_CHARGE_TYPE_SHMEM
, /* used by page migration of shmem */
174 MEM_CGROUP_CHARGE_TYPE_FORCE
, /* used by force_empty */
175 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
, /* for accounting swapcache */
179 /* only for here (for easy reading.) */
180 #define PCGF_CACHE (1UL << PCG_CACHE)
181 #define PCGF_USED (1UL << PCG_USED)
182 #define PCGF_LOCK (1UL << PCG_LOCK)
183 static const unsigned long
184 pcg_default_flags
[NR_CHARGE_TYPE
] = {
185 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* File Cache */
186 PCGF_USED
| PCGF_LOCK
, /* Anon */
187 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* Shmem */
191 /* for encoding cft->private value on file */
194 #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
195 #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
196 #define MEMFILE_ATTR(val) ((val) & 0xffff)
198 static void mem_cgroup_get(struct mem_cgroup
*mem
);
199 static void mem_cgroup_put(struct mem_cgroup
*mem
);
201 static void mem_cgroup_charge_statistics(struct mem_cgroup
*mem
,
202 struct page_cgroup
*pc
,
205 int val
= (charge
)? 1 : -1;
206 struct mem_cgroup_stat
*stat
= &mem
->stat
;
207 struct mem_cgroup_stat_cpu
*cpustat
;
210 cpustat
= &stat
->cpustat
[cpu
];
211 if (PageCgroupCache(pc
))
212 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_CACHE
, val
);
214 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_RSS
, val
);
217 __mem_cgroup_stat_add_safe(cpustat
,
218 MEM_CGROUP_STAT_PGPGIN_COUNT
, 1);
220 __mem_cgroup_stat_add_safe(cpustat
,
221 MEM_CGROUP_STAT_PGPGOUT_COUNT
, 1);
225 static struct mem_cgroup_per_zone
*
226 mem_cgroup_zoneinfo(struct mem_cgroup
*mem
, int nid
, int zid
)
228 return &mem
->info
.nodeinfo
[nid
]->zoneinfo
[zid
];
231 static struct mem_cgroup_per_zone
*
232 page_cgroup_zoneinfo(struct page_cgroup
*pc
)
234 struct mem_cgroup
*mem
= pc
->mem_cgroup
;
235 int nid
= page_cgroup_nid(pc
);
236 int zid
= page_cgroup_zid(pc
);
241 return mem_cgroup_zoneinfo(mem
, nid
, zid
);
244 static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup
*mem
,
248 struct mem_cgroup_per_zone
*mz
;
251 for_each_online_node(nid
)
252 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
253 mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
254 total
+= MEM_CGROUP_ZSTAT(mz
, idx
);
259 static struct mem_cgroup
*mem_cgroup_from_cont(struct cgroup
*cont
)
261 return container_of(cgroup_subsys_state(cont
,
262 mem_cgroup_subsys_id
), struct mem_cgroup
,
266 struct mem_cgroup
*mem_cgroup_from_task(struct task_struct
*p
)
269 * mm_update_next_owner() may clear mm->owner to NULL
270 * if it races with swapoff, page migration, etc.
271 * So this can be called with p == NULL.
276 return container_of(task_subsys_state(p
, mem_cgroup_subsys_id
),
277 struct mem_cgroup
, css
);
281 * Following LRU functions are allowed to be used without PCG_LOCK.
282 * Operations are called by routine of global LRU independently from memcg.
283 * What we have to take care of here is validness of pc->mem_cgroup.
285 * Changes to pc->mem_cgroup happens when
288 * In typical case, "charge" is done before add-to-lru. Exception is SwapCache.
289 * It is added to LRU before charge.
290 * If PCG_USED bit is not set, page_cgroup is not added to this private LRU.
291 * When moving account, the page is not on LRU. It's isolated.
294 void mem_cgroup_del_lru_list(struct page
*page
, enum lru_list lru
)
296 struct page_cgroup
*pc
;
297 struct mem_cgroup
*mem
;
298 struct mem_cgroup_per_zone
*mz
;
300 if (mem_cgroup_disabled())
302 pc
= lookup_page_cgroup(page
);
303 /* can happen while we handle swapcache. */
304 if (list_empty(&pc
->lru
))
306 mz
= page_cgroup_zoneinfo(pc
);
307 mem
= pc
->mem_cgroup
;
308 MEM_CGROUP_ZSTAT(mz
, lru
) -= 1;
309 list_del_init(&pc
->lru
);
313 void mem_cgroup_del_lru(struct page
*page
)
315 mem_cgroup_del_lru_list(page
, page_lru(page
));
318 void mem_cgroup_rotate_lru_list(struct page
*page
, enum lru_list lru
)
320 struct mem_cgroup_per_zone
*mz
;
321 struct page_cgroup
*pc
;
323 if (mem_cgroup_disabled())
326 pc
= lookup_page_cgroup(page
);
328 /* unused page is not rotated. */
329 if (!PageCgroupUsed(pc
))
331 mz
= page_cgroup_zoneinfo(pc
);
332 list_move(&pc
->lru
, &mz
->lists
[lru
]);
335 void mem_cgroup_add_lru_list(struct page
*page
, enum lru_list lru
)
337 struct page_cgroup
*pc
;
338 struct mem_cgroup_per_zone
*mz
;
340 if (mem_cgroup_disabled())
342 pc
= lookup_page_cgroup(page
);
343 /* barrier to sync with "charge" */
345 if (!PageCgroupUsed(pc
))
348 mz
= page_cgroup_zoneinfo(pc
);
349 MEM_CGROUP_ZSTAT(mz
, lru
) += 1;
350 list_add(&pc
->lru
, &mz
->lists
[lru
]);
353 * To add swapcache into LRU. Be careful to all this function.
354 * zone->lru_lock shouldn't be held and irq must not be disabled.
356 static void mem_cgroup_lru_fixup(struct page
*page
)
358 if (!isolate_lru_page(page
))
359 putback_lru_page(page
);
362 void mem_cgroup_move_lists(struct page
*page
,
363 enum lru_list from
, enum lru_list to
)
365 if (mem_cgroup_disabled())
367 mem_cgroup_del_lru_list(page
, from
);
368 mem_cgroup_add_lru_list(page
, to
);
371 int task_in_mem_cgroup(struct task_struct
*task
, const struct mem_cgroup
*mem
)
376 ret
= task
->mm
&& mm_match_cgroup(task
->mm
, mem
);
382 * Calculate mapped_ratio under memory controller. This will be used in
383 * vmscan.c for deteremining we have to reclaim mapped pages.
385 int mem_cgroup_calc_mapped_ratio(struct mem_cgroup
*mem
)
390 * usage is recorded in bytes. But, here, we assume the number of
391 * physical pages can be represented by "long" on any arch.
393 total
= (long) (mem
->res
.usage
>> PAGE_SHIFT
) + 1L;
394 rss
= (long)mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_RSS
);
395 return (int)((rss
* 100L) / total
);
399 * prev_priority control...this will be used in memory reclaim path.
401 int mem_cgroup_get_reclaim_priority(struct mem_cgroup
*mem
)
403 return mem
->prev_priority
;
406 void mem_cgroup_note_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
408 if (priority
< mem
->prev_priority
)
409 mem
->prev_priority
= priority
;
412 void mem_cgroup_record_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
414 mem
->prev_priority
= priority
;
418 * Calculate # of pages to be scanned in this priority/zone.
421 * priority starts from "DEF_PRIORITY" and decremented in each loop.
422 * (see include/linux/mmzone.h)
425 long mem_cgroup_calc_reclaim(struct mem_cgroup
*mem
, struct zone
*zone
,
426 int priority
, enum lru_list lru
)
429 int nid
= zone
->zone_pgdat
->node_id
;
430 int zid
= zone_idx(zone
);
431 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
433 nr_pages
= MEM_CGROUP_ZSTAT(mz
, lru
);
435 return (nr_pages
>> priority
);
438 int mem_cgroup_inactive_anon_is_low(struct mem_cgroup
*memcg
, struct zone
*zone
)
440 unsigned long active
;
441 unsigned long inactive
;
443 inactive
= mem_cgroup_get_all_zonestat(memcg
, LRU_INACTIVE_ANON
);
444 active
= mem_cgroup_get_all_zonestat(memcg
, LRU_ACTIVE_ANON
);
446 if (inactive
* memcg
->inactive_ratio
< active
)
452 unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup
*memcg
,
456 int nid
= zone
->zone_pgdat
->node_id
;
457 int zid
= zone_idx(zone
);
458 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(memcg
, nid
, zid
);
460 return MEM_CGROUP_ZSTAT(mz
, lru
);
463 struct zone_reclaim_stat
*mem_cgroup_get_reclaim_stat(struct mem_cgroup
*memcg
,
466 int nid
= zone
->zone_pgdat
->node_id
;
467 int zid
= zone_idx(zone
);
468 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(memcg
, nid
, zid
);
470 return &mz
->reclaim_stat
;
473 struct zone_reclaim_stat
*
474 mem_cgroup_get_reclaim_stat_from_page(struct page
*page
)
476 struct page_cgroup
*pc
;
477 struct mem_cgroup_per_zone
*mz
;
479 if (mem_cgroup_disabled())
482 pc
= lookup_page_cgroup(page
);
483 mz
= page_cgroup_zoneinfo(pc
);
487 return &mz
->reclaim_stat
;
490 unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan
,
491 struct list_head
*dst
,
492 unsigned long *scanned
, int order
,
493 int mode
, struct zone
*z
,
494 struct mem_cgroup
*mem_cont
,
495 int active
, int file
)
497 unsigned long nr_taken
= 0;
501 struct list_head
*src
;
502 struct page_cgroup
*pc
, *tmp
;
503 int nid
= z
->zone_pgdat
->node_id
;
504 int zid
= zone_idx(z
);
505 struct mem_cgroup_per_zone
*mz
;
506 int lru
= LRU_FILE
* !!file
+ !!active
;
509 mz
= mem_cgroup_zoneinfo(mem_cont
, nid
, zid
);
510 src
= &mz
->lists
[lru
];
513 list_for_each_entry_safe_reverse(pc
, tmp
, src
, lru
) {
514 if (scan
>= nr_to_scan
)
518 if (unlikely(!PageCgroupUsed(pc
)))
520 if (unlikely(!PageLRU(page
)))
524 if (__isolate_lru_page(page
, mode
, file
) == 0) {
525 list_move(&page
->lru
, dst
);
534 #define mem_cgroup_from_res_counter(counter, member) \
535 container_of(counter, struct mem_cgroup, member)
538 * This routine finds the DFS walk successor. This routine should be
539 * called with cgroup_mutex held
541 static struct mem_cgroup
*
542 mem_cgroup_get_next_node(struct mem_cgroup
*curr
, struct mem_cgroup
*root_mem
)
544 struct cgroup
*cgroup
, *curr_cgroup
, *root_cgroup
;
546 curr_cgroup
= curr
->css
.cgroup
;
547 root_cgroup
= root_mem
->css
.cgroup
;
549 if (!list_empty(&curr_cgroup
->children
)) {
551 * Walk down to children
553 mem_cgroup_put(curr
);
554 cgroup
= list_entry(curr_cgroup
->children
.next
,
555 struct cgroup
, sibling
);
556 curr
= mem_cgroup_from_cont(cgroup
);
557 mem_cgroup_get(curr
);
562 if (curr_cgroup
== root_cgroup
) {
563 mem_cgroup_put(curr
);
565 mem_cgroup_get(curr
);
572 if (curr_cgroup
->sibling
.next
!= &curr_cgroup
->parent
->children
) {
573 mem_cgroup_put(curr
);
574 cgroup
= list_entry(curr_cgroup
->sibling
.next
, struct cgroup
,
576 curr
= mem_cgroup_from_cont(cgroup
);
577 mem_cgroup_get(curr
);
582 * Go up to next parent and next parent's sibling if need be
584 curr_cgroup
= curr_cgroup
->parent
;
588 root_mem
->last_scanned_child
= curr
;
593 * Visit the first child (need not be the first child as per the ordering
594 * of the cgroup list, since we track last_scanned_child) of @mem and use
595 * that to reclaim free pages from.
597 static struct mem_cgroup
*
598 mem_cgroup_get_first_node(struct mem_cgroup
*root_mem
)
600 struct cgroup
*cgroup
;
601 struct mem_cgroup
*ret
;
602 bool obsolete
= (root_mem
->last_scanned_child
&&
603 root_mem
->last_scanned_child
->obsolete
);
606 * Scan all children under the mem_cgroup mem
609 if (list_empty(&root_mem
->css
.cgroup
->children
)) {
614 if (!root_mem
->last_scanned_child
|| obsolete
) {
617 mem_cgroup_put(root_mem
->last_scanned_child
);
619 cgroup
= list_first_entry(&root_mem
->css
.cgroup
->children
,
620 struct cgroup
, sibling
);
621 ret
= mem_cgroup_from_cont(cgroup
);
624 ret
= mem_cgroup_get_next_node(root_mem
->last_scanned_child
,
628 root_mem
->last_scanned_child
= ret
;
633 static bool mem_cgroup_check_under_limit(struct mem_cgroup
*mem
)
635 if (do_swap_account
) {
636 if (res_counter_check_under_limit(&mem
->res
) &&
637 res_counter_check_under_limit(&mem
->memsw
))
640 if (res_counter_check_under_limit(&mem
->res
))
646 * Dance down the hierarchy if needed to reclaim memory. We remember the
647 * last child we reclaimed from, so that we don't end up penalizing
648 * one child extensively based on its position in the children list.
650 * root_mem is the original ancestor that we've been reclaim from.
652 static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup
*root_mem
,
653 gfp_t gfp_mask
, bool noswap
)
655 struct mem_cgroup
*next_mem
;
659 * Reclaim unconditionally and don't check for return value.
660 * We need to reclaim in the current group and down the tree.
661 * One might think about checking for children before reclaiming,
662 * but there might be left over accounting, even after children
665 ret
= try_to_free_mem_cgroup_pages(root_mem
, gfp_mask
, noswap
);
666 if (mem_cgroup_check_under_limit(root_mem
))
668 if (!root_mem
->use_hierarchy
)
671 next_mem
= mem_cgroup_get_first_node(root_mem
);
673 while (next_mem
!= root_mem
) {
674 if (next_mem
->obsolete
) {
675 mem_cgroup_put(next_mem
);
677 next_mem
= mem_cgroup_get_first_node(root_mem
);
681 ret
= try_to_free_mem_cgroup_pages(next_mem
, gfp_mask
, noswap
);
682 if (mem_cgroup_check_under_limit(root_mem
))
685 next_mem
= mem_cgroup_get_next_node(next_mem
, root_mem
);
691 bool mem_cgroup_oom_called(struct task_struct
*task
)
694 struct mem_cgroup
*mem
;
695 struct mm_struct
*mm
;
701 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
702 if (mem
&& time_before(jiffies
, mem
->last_oom_jiffies
+ HZ
/10))
708 * Unlike exported interface, "oom" parameter is added. if oom==true,
709 * oom-killer can be invoked.
711 static int __mem_cgroup_try_charge(struct mm_struct
*mm
,
712 gfp_t gfp_mask
, struct mem_cgroup
**memcg
,
715 struct mem_cgroup
*mem
, *mem_over_limit
;
716 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
717 struct res_counter
*fail_res
;
719 if (unlikely(test_thread_flag(TIF_MEMDIE
))) {
720 /* Don't account this! */
726 * We always charge the cgroup the mm_struct belongs to.
727 * The mm_struct's mem_cgroup changes on task migration if the
728 * thread group leader migrates. It's possible that mm is not
729 * set, if so charge the init_mm (happens for pagecache usage).
731 if (likely(!*memcg
)) {
733 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
734 if (unlikely(!mem
)) {
739 * For every charge from the cgroup, increment reference count
753 ret
= res_counter_charge(&mem
->res
, PAGE_SIZE
, &fail_res
);
755 if (!do_swap_account
)
757 ret
= res_counter_charge(&mem
->memsw
, PAGE_SIZE
,
761 /* mem+swap counter fails */
762 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
764 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
767 /* mem counter fails */
768 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
771 if (!(gfp_mask
& __GFP_WAIT
))
774 ret
= mem_cgroup_hierarchical_reclaim(mem_over_limit
, gfp_mask
,
778 * try_to_free_mem_cgroup_pages() might not give us a full
779 * picture of reclaim. Some pages are reclaimed and might be
780 * moved to swap cache or just unmapped from the cgroup.
781 * Check the limit again to see if the reclaim reduced the
782 * current usage of the cgroup before giving up
785 if (mem_cgroup_check_under_limit(mem_over_limit
))
790 mem_cgroup_out_of_memory(mem_over_limit
, gfp_mask
);
791 mem_over_limit
->last_oom_jiffies
= jiffies
;
803 * mem_cgroup_try_charge - get charge of PAGE_SIZE.
804 * @mm: an mm_struct which is charged against. (when *memcg is NULL)
805 * @gfp_mask: gfp_mask for reclaim.
806 * @memcg: a pointer to memory cgroup which is charged against.
808 * charge against memory cgroup pointed by *memcg. if *memcg == NULL, estimated
809 * memory cgroup from @mm is got and stored in *memcg.
811 * Returns 0 if success. -ENOMEM at failure.
812 * This call can invoke OOM-Killer.
815 int mem_cgroup_try_charge(struct mm_struct
*mm
,
816 gfp_t mask
, struct mem_cgroup
**memcg
)
818 return __mem_cgroup_try_charge(mm
, mask
, memcg
, true);
822 * commit a charge got by mem_cgroup_try_charge() and makes page_cgroup to be
823 * USED state. If already USED, uncharge and return.
826 static void __mem_cgroup_commit_charge(struct mem_cgroup
*mem
,
827 struct page_cgroup
*pc
,
828 enum charge_type ctype
)
830 /* try_charge() can return NULL to *memcg, taking care of it. */
834 lock_page_cgroup(pc
);
835 if (unlikely(PageCgroupUsed(pc
))) {
836 unlock_page_cgroup(pc
);
837 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
839 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
843 pc
->mem_cgroup
= mem
;
845 pc
->flags
= pcg_default_flags
[ctype
];
847 mem_cgroup_charge_statistics(mem
, pc
, true);
849 unlock_page_cgroup(pc
);
853 * mem_cgroup_move_account - move account of the page
854 * @pc: page_cgroup of the page.
855 * @from: mem_cgroup which the page is moved from.
856 * @to: mem_cgroup which the page is moved to. @from != @to.
858 * The caller must confirm following.
859 * - page is not on LRU (isolate_page() is useful.)
861 * returns 0 at success,
862 * returns -EBUSY when lock is busy or "pc" is unstable.
864 * This function does "uncharge" from old cgroup but doesn't do "charge" to
865 * new cgroup. It should be done by a caller.
868 static int mem_cgroup_move_account(struct page_cgroup
*pc
,
869 struct mem_cgroup
*from
, struct mem_cgroup
*to
)
871 struct mem_cgroup_per_zone
*from_mz
, *to_mz
;
875 VM_BUG_ON(from
== to
);
876 VM_BUG_ON(PageLRU(pc
->page
));
878 nid
= page_cgroup_nid(pc
);
879 zid
= page_cgroup_zid(pc
);
880 from_mz
= mem_cgroup_zoneinfo(from
, nid
, zid
);
881 to_mz
= mem_cgroup_zoneinfo(to
, nid
, zid
);
883 if (!trylock_page_cgroup(pc
))
886 if (!PageCgroupUsed(pc
))
889 if (pc
->mem_cgroup
!= from
)
893 res_counter_uncharge(&from
->res
, PAGE_SIZE
);
894 mem_cgroup_charge_statistics(from
, pc
, false);
896 res_counter_uncharge(&from
->memsw
, PAGE_SIZE
);
898 mem_cgroup_charge_statistics(to
, pc
, true);
902 unlock_page_cgroup(pc
);
907 * move charges to its parent.
910 static int mem_cgroup_move_parent(struct page_cgroup
*pc
,
911 struct mem_cgroup
*child
,
914 struct page
*page
= pc
->page
;
915 struct cgroup
*cg
= child
->css
.cgroup
;
916 struct cgroup
*pcg
= cg
->parent
;
917 struct mem_cgroup
*parent
;
925 parent
= mem_cgroup_from_cont(pcg
);
928 ret
= __mem_cgroup_try_charge(NULL
, gfp_mask
, &parent
, false);
932 if (!get_page_unless_zero(page
))
935 ret
= isolate_lru_page(page
);
940 ret
= mem_cgroup_move_account(pc
, child
, parent
);
942 /* drop extra refcnt by try_charge() (move_account increment one) */
943 css_put(&parent
->css
);
944 putback_lru_page(page
);
949 /* uncharge if move fails */
951 res_counter_uncharge(&parent
->res
, PAGE_SIZE
);
953 res_counter_uncharge(&parent
->memsw
, PAGE_SIZE
);
959 * Charge the memory controller for page usage.
961 * 0 if the charge was successful
962 * < 0 if the cgroup is over its limit
964 static int mem_cgroup_charge_common(struct page
*page
, struct mm_struct
*mm
,
965 gfp_t gfp_mask
, enum charge_type ctype
,
966 struct mem_cgroup
*memcg
)
968 struct mem_cgroup
*mem
;
969 struct page_cgroup
*pc
;
972 pc
= lookup_page_cgroup(page
);
973 /* can happen at boot */
979 ret
= __mem_cgroup_try_charge(mm
, gfp_mask
, &mem
, true);
983 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
987 int mem_cgroup_newpage_charge(struct page
*page
,
988 struct mm_struct
*mm
, gfp_t gfp_mask
)
990 if (mem_cgroup_disabled())
992 if (PageCompound(page
))
995 * If already mapped, we don't have to account.
996 * If page cache, page->mapping has address_space.
997 * But page->mapping may have out-of-use anon_vma pointer,
998 * detecit it by PageAnon() check. newly-mapped-anon's page->mapping
1001 if (page_mapped(page
) || (page
->mapping
&& !PageAnon(page
)))
1005 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1006 MEM_CGROUP_CHARGE_TYPE_MAPPED
, NULL
);
1009 int mem_cgroup_cache_charge(struct page
*page
, struct mm_struct
*mm
,
1012 if (mem_cgroup_disabled())
1014 if (PageCompound(page
))
1017 * Corner case handling. This is called from add_to_page_cache()
1018 * in usual. But some FS (shmem) precharges this page before calling it
1019 * and call add_to_page_cache() with GFP_NOWAIT.
1021 * For GFP_NOWAIT case, the page may be pre-charged before calling
1022 * add_to_page_cache(). (See shmem.c) check it here and avoid to call
1023 * charge twice. (It works but has to pay a bit larger cost.)
1025 if (!(gfp_mask
& __GFP_WAIT
)) {
1026 struct page_cgroup
*pc
;
1029 pc
= lookup_page_cgroup(page
);
1032 lock_page_cgroup(pc
);
1033 if (PageCgroupUsed(pc
)) {
1034 unlock_page_cgroup(pc
);
1037 unlock_page_cgroup(pc
);
1043 if (page_is_file_cache(page
))
1044 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1045 MEM_CGROUP_CHARGE_TYPE_CACHE
, NULL
);
1047 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1048 MEM_CGROUP_CHARGE_TYPE_SHMEM
, NULL
);
1051 int mem_cgroup_try_charge_swapin(struct mm_struct
*mm
,
1053 gfp_t mask
, struct mem_cgroup
**ptr
)
1055 struct mem_cgroup
*mem
;
1058 if (mem_cgroup_disabled())
1061 if (!do_swap_account
)
1065 * A racing thread's fault, or swapoff, may have already updated
1066 * the pte, and even removed page from swap cache: return success
1067 * to go on to do_swap_page()'s pte_same() test, which should fail.
1069 if (!PageSwapCache(page
))
1072 ent
.val
= page_private(page
);
1074 mem
= lookup_swap_cgroup(ent
);
1075 if (!mem
|| mem
->obsolete
)
1078 return __mem_cgroup_try_charge(NULL
, mask
, ptr
, true);
1082 return __mem_cgroup_try_charge(mm
, mask
, ptr
, true);
1087 int mem_cgroup_cache_charge_swapin(struct page
*page
,
1088 struct mm_struct
*mm
, gfp_t mask
, bool locked
)
1092 if (mem_cgroup_disabled())
1099 * If not locked, the page can be dropped from SwapCache until
1102 if (PageSwapCache(page
)) {
1103 struct mem_cgroup
*mem
= NULL
;
1106 ent
.val
= page_private(page
);
1107 if (do_swap_account
) {
1108 mem
= lookup_swap_cgroup(ent
);
1109 if (mem
&& mem
->obsolete
)
1114 ret
= mem_cgroup_charge_common(page
, mm
, mask
,
1115 MEM_CGROUP_CHARGE_TYPE_SHMEM
, mem
);
1117 if (!ret
&& do_swap_account
) {
1118 /* avoid double counting */
1119 mem
= swap_cgroup_record(ent
, NULL
);
1121 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1122 mem_cgroup_put(mem
);
1128 /* add this page(page_cgroup) to the LRU we want. */
1129 mem_cgroup_lru_fixup(page
);
1135 void mem_cgroup_commit_charge_swapin(struct page
*page
, struct mem_cgroup
*ptr
)
1137 struct page_cgroup
*pc
;
1139 if (mem_cgroup_disabled())
1143 pc
= lookup_page_cgroup(page
);
1144 __mem_cgroup_commit_charge(ptr
, pc
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1146 * Now swap is on-memory. This means this page may be
1147 * counted both as mem and swap....double count.
1148 * Fix it by uncharging from memsw. This SwapCache is stable
1149 * because we're still under lock_page().
1151 if (do_swap_account
) {
1152 swp_entry_t ent
= {.val
= page_private(page
)};
1153 struct mem_cgroup
*memcg
;
1154 memcg
= swap_cgroup_record(ent
, NULL
);
1156 /* If memcg is obsolete, memcg can be != ptr */
1157 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1158 mem_cgroup_put(memcg
);
1162 /* add this page(page_cgroup) to the LRU we want. */
1163 mem_cgroup_lru_fixup(page
);
1166 void mem_cgroup_cancel_charge_swapin(struct mem_cgroup
*mem
)
1168 if (mem_cgroup_disabled())
1172 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1173 if (do_swap_account
)
1174 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1180 * uncharge if !page_mapped(page)
1182 static struct mem_cgroup
*
1183 __mem_cgroup_uncharge_common(struct page
*page
, enum charge_type ctype
)
1185 struct page_cgroup
*pc
;
1186 struct mem_cgroup
*mem
= NULL
;
1187 struct mem_cgroup_per_zone
*mz
;
1189 if (mem_cgroup_disabled())
1192 if (PageSwapCache(page
))
1196 * Check if our page_cgroup is valid
1198 pc
= lookup_page_cgroup(page
);
1199 if (unlikely(!pc
|| !PageCgroupUsed(pc
)))
1202 lock_page_cgroup(pc
);
1204 mem
= pc
->mem_cgroup
;
1206 if (!PageCgroupUsed(pc
))
1210 case MEM_CGROUP_CHARGE_TYPE_MAPPED
:
1211 if (page_mapped(page
))
1214 case MEM_CGROUP_CHARGE_TYPE_SWAPOUT
:
1215 if (!PageAnon(page
)) { /* Shared memory */
1216 if (page
->mapping
&& !page_is_file_cache(page
))
1218 } else if (page_mapped(page
)) /* Anon */
1225 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1226 if (do_swap_account
&& (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
))
1227 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1229 mem_cgroup_charge_statistics(mem
, pc
, false);
1230 ClearPageCgroupUsed(pc
);
1232 mz
= page_cgroup_zoneinfo(pc
);
1233 unlock_page_cgroup(pc
);
1235 /* at swapout, this memcg will be accessed to record to swap */
1236 if (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
)
1242 unlock_page_cgroup(pc
);
1246 void mem_cgroup_uncharge_page(struct page
*page
)
1249 if (page_mapped(page
))
1251 if (page
->mapping
&& !PageAnon(page
))
1253 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1256 void mem_cgroup_uncharge_cache_page(struct page
*page
)
1258 VM_BUG_ON(page_mapped(page
));
1259 VM_BUG_ON(page
->mapping
);
1260 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_CACHE
);
1264 * called from __delete_from_swap_cache() and drop "page" account.
1265 * memcg information is recorded to swap_cgroup of "ent"
1267 void mem_cgroup_uncharge_swapcache(struct page
*page
, swp_entry_t ent
)
1269 struct mem_cgroup
*memcg
;
1271 memcg
= __mem_cgroup_uncharge_common(page
,
1272 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
);
1273 /* record memcg information */
1274 if (do_swap_account
&& memcg
) {
1275 swap_cgroup_record(ent
, memcg
);
1276 mem_cgroup_get(memcg
);
1279 css_put(&memcg
->css
);
1282 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1284 * called from swap_entry_free(). remove record in swap_cgroup and
1285 * uncharge "memsw" account.
1287 void mem_cgroup_uncharge_swap(swp_entry_t ent
)
1289 struct mem_cgroup
*memcg
;
1291 if (!do_swap_account
)
1294 memcg
= swap_cgroup_record(ent
, NULL
);
1296 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1297 mem_cgroup_put(memcg
);
1303 * Before starting migration, account PAGE_SIZE to mem_cgroup that the old
1306 int mem_cgroup_prepare_migration(struct page
*page
, struct mem_cgroup
**ptr
)
1308 struct page_cgroup
*pc
;
1309 struct mem_cgroup
*mem
= NULL
;
1312 if (mem_cgroup_disabled())
1315 pc
= lookup_page_cgroup(page
);
1316 lock_page_cgroup(pc
);
1317 if (PageCgroupUsed(pc
)) {
1318 mem
= pc
->mem_cgroup
;
1321 unlock_page_cgroup(pc
);
1324 ret
= mem_cgroup_try_charge(NULL
, GFP_KERNEL
, &mem
);
1331 /* remove redundant charge if migration failed*/
1332 void mem_cgroup_end_migration(struct mem_cgroup
*mem
,
1333 struct page
*oldpage
, struct page
*newpage
)
1335 struct page
*target
, *unused
;
1336 struct page_cgroup
*pc
;
1337 enum charge_type ctype
;
1342 /* at migration success, oldpage->mapping is NULL. */
1343 if (oldpage
->mapping
) {
1351 if (PageAnon(target
))
1352 ctype
= MEM_CGROUP_CHARGE_TYPE_MAPPED
;
1353 else if (page_is_file_cache(target
))
1354 ctype
= MEM_CGROUP_CHARGE_TYPE_CACHE
;
1356 ctype
= MEM_CGROUP_CHARGE_TYPE_SHMEM
;
1358 /* unused page is not on radix-tree now. */
1360 __mem_cgroup_uncharge_common(unused
, ctype
);
1362 pc
= lookup_page_cgroup(target
);
1364 * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
1365 * So, double-counting is effectively avoided.
1367 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
1370 * Both of oldpage and newpage are still under lock_page().
1371 * Then, we don't have to care about race in radix-tree.
1372 * But we have to be careful that this page is unmapped or not.
1374 * There is a case for !page_mapped(). At the start of
1375 * migration, oldpage was mapped. But now, it's zapped.
1376 * But we know *target* page is not freed/reused under us.
1377 * mem_cgroup_uncharge_page() does all necessary checks.
1379 if (ctype
== MEM_CGROUP_CHARGE_TYPE_MAPPED
)
1380 mem_cgroup_uncharge_page(target
);
1384 * A call to try to shrink memory usage under specified resource controller.
1385 * This is typically used for page reclaiming for shmem for reducing side
1386 * effect of page allocation from shmem, which is used by some mem_cgroup.
1388 int mem_cgroup_shrink_usage(struct mm_struct
*mm
, gfp_t gfp_mask
)
1390 struct mem_cgroup
*mem
;
1392 int retry
= MEM_CGROUP_RECLAIM_RETRIES
;
1394 if (mem_cgroup_disabled())
1400 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
1401 if (unlikely(!mem
)) {
1409 progress
= try_to_free_mem_cgroup_pages(mem
, gfp_mask
, true);
1410 progress
+= mem_cgroup_check_under_limit(mem
);
1411 } while (!progress
&& --retry
);
1420 * The inactive anon list should be small enough that the VM never has to
1421 * do too much work, but large enough that each inactive page has a chance
1422 * to be referenced again before it is swapped out.
1424 * this calculation is straightforward porting from
1425 * page_alloc.c::setup_per_zone_inactive_ratio().
1426 * it describe more detail.
1428 static void mem_cgroup_set_inactive_ratio(struct mem_cgroup
*memcg
)
1430 unsigned int gb
, ratio
;
1432 gb
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
) >> 30;
1434 ratio
= int_sqrt(10 * gb
);
1438 memcg
->inactive_ratio
= ratio
;
1442 static DEFINE_MUTEX(set_limit_mutex
);
1444 static int mem_cgroup_resize_limit(struct mem_cgroup
*memcg
,
1445 unsigned long long val
)
1448 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1453 while (retry_count
) {
1454 if (signal_pending(current
)) {
1459 * Rather than hide all in some function, I do this in
1460 * open coded manner. You see what this really does.
1461 * We have to guarantee mem->res.limit < mem->memsw.limit.
1463 mutex_lock(&set_limit_mutex
);
1464 memswlimit
= res_counter_read_u64(&memcg
->memsw
, RES_LIMIT
);
1465 if (memswlimit
< val
) {
1467 mutex_unlock(&set_limit_mutex
);
1470 ret
= res_counter_set_limit(&memcg
->res
, val
);
1471 mutex_unlock(&set_limit_mutex
);
1476 progress
= try_to_free_mem_cgroup_pages(memcg
,
1478 if (!progress
) retry_count
--;
1482 mem_cgroup_set_inactive_ratio(memcg
);
1487 int mem_cgroup_resize_memsw_limit(struct mem_cgroup
*memcg
,
1488 unsigned long long val
)
1490 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1491 u64 memlimit
, oldusage
, curusage
;
1494 if (!do_swap_account
)
1497 while (retry_count
) {
1498 if (signal_pending(current
)) {
1503 * Rather than hide all in some function, I do this in
1504 * open coded manner. You see what this really does.
1505 * We have to guarantee mem->res.limit < mem->memsw.limit.
1507 mutex_lock(&set_limit_mutex
);
1508 memlimit
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
);
1509 if (memlimit
> val
) {
1511 mutex_unlock(&set_limit_mutex
);
1514 ret
= res_counter_set_limit(&memcg
->memsw
, val
);
1515 mutex_unlock(&set_limit_mutex
);
1520 oldusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1521 try_to_free_mem_cgroup_pages(memcg
, GFP_KERNEL
, true);
1522 curusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1523 if (curusage
>= oldusage
)
1530 * This routine traverse page_cgroup in given list and drop them all.
1531 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
1533 static int mem_cgroup_force_empty_list(struct mem_cgroup
*mem
,
1534 int node
, int zid
, enum lru_list lru
)
1537 struct mem_cgroup_per_zone
*mz
;
1538 struct page_cgroup
*pc
, *busy
;
1539 unsigned long flags
, loop
;
1540 struct list_head
*list
;
1543 zone
= &NODE_DATA(node
)->node_zones
[zid
];
1544 mz
= mem_cgroup_zoneinfo(mem
, node
, zid
);
1545 list
= &mz
->lists
[lru
];
1547 loop
= MEM_CGROUP_ZSTAT(mz
, lru
);
1548 /* give some margin against EBUSY etc...*/
1553 spin_lock_irqsave(&zone
->lru_lock
, flags
);
1554 if (list_empty(list
)) {
1555 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1558 pc
= list_entry(list
->prev
, struct page_cgroup
, lru
);
1560 list_move(&pc
->lru
, list
);
1562 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1565 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1567 ret
= mem_cgroup_move_parent(pc
, mem
, GFP_KERNEL
);
1571 if (ret
== -EBUSY
|| ret
== -EINVAL
) {
1572 /* found lock contention or "pc" is obsolete. */
1579 if (!ret
&& !list_empty(list
))
1585 * make mem_cgroup's charge to be 0 if there is no task.
1586 * This enables deleting this mem_cgroup.
1588 static int mem_cgroup_force_empty(struct mem_cgroup
*mem
, bool free_all
)
1591 int node
, zid
, shrink
;
1592 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
1593 struct cgroup
*cgrp
= mem
->css
.cgroup
;
1598 /* should free all ? */
1602 while (mem
->res
.usage
> 0) {
1604 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
))
1607 if (signal_pending(current
))
1609 /* This is for making all *used* pages to be on LRU. */
1610 lru_add_drain_all();
1612 for_each_node_state(node
, N_POSSIBLE
) {
1613 for (zid
= 0; !ret
&& zid
< MAX_NR_ZONES
; zid
++) {
1616 ret
= mem_cgroup_force_empty_list(mem
,
1625 /* it seems parent cgroup doesn't have enough mem */
1636 /* returns EBUSY if there is a task or if we come here twice. */
1637 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
) || shrink
) {
1641 /* we call try-to-free pages for make this cgroup empty */
1642 lru_add_drain_all();
1643 /* try to free all pages in this cgroup */
1645 while (nr_retries
&& mem
->res
.usage
> 0) {
1648 if (signal_pending(current
)) {
1652 progress
= try_to_free_mem_cgroup_pages(mem
,
1656 /* maybe some writeback is necessary */
1657 congestion_wait(WRITE
, HZ
/10);
1662 /* try move_account...there may be some *locked* pages. */
1669 int mem_cgroup_force_empty_write(struct cgroup
*cont
, unsigned int event
)
1671 return mem_cgroup_force_empty(mem_cgroup_from_cont(cont
), true);
1675 static u64
mem_cgroup_hierarchy_read(struct cgroup
*cont
, struct cftype
*cft
)
1677 return mem_cgroup_from_cont(cont
)->use_hierarchy
;
1680 static int mem_cgroup_hierarchy_write(struct cgroup
*cont
, struct cftype
*cft
,
1684 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1685 struct cgroup
*parent
= cont
->parent
;
1686 struct mem_cgroup
*parent_mem
= NULL
;
1689 parent_mem
= mem_cgroup_from_cont(parent
);
1693 * If parent's use_hiearchy is set, we can't make any modifications
1694 * in the child subtrees. If it is unset, then the change can
1695 * occur, provided the current cgroup has no children.
1697 * For the root cgroup, parent_mem is NULL, we allow value to be
1698 * set if there are no children.
1700 if ((!parent_mem
|| !parent_mem
->use_hierarchy
) &&
1701 (val
== 1 || val
== 0)) {
1702 if (list_empty(&cont
->children
))
1703 mem
->use_hierarchy
= val
;
1713 static u64
mem_cgroup_read(struct cgroup
*cont
, struct cftype
*cft
)
1715 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1719 type
= MEMFILE_TYPE(cft
->private);
1720 name
= MEMFILE_ATTR(cft
->private);
1723 val
= res_counter_read_u64(&mem
->res
, name
);
1726 if (do_swap_account
)
1727 val
= res_counter_read_u64(&mem
->memsw
, name
);
1736 * The user of this function is...
1739 static int mem_cgroup_write(struct cgroup
*cont
, struct cftype
*cft
,
1742 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cont
);
1744 unsigned long long val
;
1747 type
= MEMFILE_TYPE(cft
->private);
1748 name
= MEMFILE_ATTR(cft
->private);
1751 /* This function does all necessary parse...reuse it */
1752 ret
= res_counter_memparse_write_strategy(buffer
, &val
);
1756 ret
= mem_cgroup_resize_limit(memcg
, val
);
1758 ret
= mem_cgroup_resize_memsw_limit(memcg
, val
);
1761 ret
= -EINVAL
; /* should be BUG() ? */
1767 static int mem_cgroup_reset(struct cgroup
*cont
, unsigned int event
)
1769 struct mem_cgroup
*mem
;
1772 mem
= mem_cgroup_from_cont(cont
);
1773 type
= MEMFILE_TYPE(event
);
1774 name
= MEMFILE_ATTR(event
);
1778 res_counter_reset_max(&mem
->res
);
1780 res_counter_reset_max(&mem
->memsw
);
1784 res_counter_reset_failcnt(&mem
->res
);
1786 res_counter_reset_failcnt(&mem
->memsw
);
1792 static const struct mem_cgroup_stat_desc
{
1795 } mem_cgroup_stat_desc
[] = {
1796 [MEM_CGROUP_STAT_CACHE
] = { "cache", PAGE_SIZE
, },
1797 [MEM_CGROUP_STAT_RSS
] = { "rss", PAGE_SIZE
, },
1798 [MEM_CGROUP_STAT_PGPGIN_COUNT
] = {"pgpgin", 1, },
1799 [MEM_CGROUP_STAT_PGPGOUT_COUNT
] = {"pgpgout", 1, },
1802 static int mem_control_stat_show(struct cgroup
*cont
, struct cftype
*cft
,
1803 struct cgroup_map_cb
*cb
)
1805 struct mem_cgroup
*mem_cont
= mem_cgroup_from_cont(cont
);
1806 struct mem_cgroup_stat
*stat
= &mem_cont
->stat
;
1809 for (i
= 0; i
< ARRAY_SIZE(stat
->cpustat
[0].count
); i
++) {
1812 val
= mem_cgroup_read_stat(stat
, i
);
1813 val
*= mem_cgroup_stat_desc
[i
].unit
;
1814 cb
->fill(cb
, mem_cgroup_stat_desc
[i
].msg
, val
);
1816 /* showing # of active pages */
1818 unsigned long active_anon
, inactive_anon
;
1819 unsigned long active_file
, inactive_file
;
1820 unsigned long unevictable
;
1822 inactive_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1824 active_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1826 inactive_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1828 active_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1830 unevictable
= mem_cgroup_get_all_zonestat(mem_cont
,
1833 cb
->fill(cb
, "active_anon", (active_anon
) * PAGE_SIZE
);
1834 cb
->fill(cb
, "inactive_anon", (inactive_anon
) * PAGE_SIZE
);
1835 cb
->fill(cb
, "active_file", (active_file
) * PAGE_SIZE
);
1836 cb
->fill(cb
, "inactive_file", (inactive_file
) * PAGE_SIZE
);
1837 cb
->fill(cb
, "unevictable", unevictable
* PAGE_SIZE
);
1844 static struct cftype mem_cgroup_files
[] = {
1846 .name
= "usage_in_bytes",
1847 .private = MEMFILE_PRIVATE(_MEM
, RES_USAGE
),
1848 .read_u64
= mem_cgroup_read
,
1851 .name
= "max_usage_in_bytes",
1852 .private = MEMFILE_PRIVATE(_MEM
, RES_MAX_USAGE
),
1853 .trigger
= mem_cgroup_reset
,
1854 .read_u64
= mem_cgroup_read
,
1857 .name
= "limit_in_bytes",
1858 .private = MEMFILE_PRIVATE(_MEM
, RES_LIMIT
),
1859 .write_string
= mem_cgroup_write
,
1860 .read_u64
= mem_cgroup_read
,
1864 .private = MEMFILE_PRIVATE(_MEM
, RES_FAILCNT
),
1865 .trigger
= mem_cgroup_reset
,
1866 .read_u64
= mem_cgroup_read
,
1870 .read_map
= mem_control_stat_show
,
1873 .name
= "force_empty",
1874 .trigger
= mem_cgroup_force_empty_write
,
1877 .name
= "use_hierarchy",
1878 .write_u64
= mem_cgroup_hierarchy_write
,
1879 .read_u64
= mem_cgroup_hierarchy_read
,
1883 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1884 static struct cftype memsw_cgroup_files
[] = {
1886 .name
= "memsw.usage_in_bytes",
1887 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_USAGE
),
1888 .read_u64
= mem_cgroup_read
,
1891 .name
= "memsw.max_usage_in_bytes",
1892 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_MAX_USAGE
),
1893 .trigger
= mem_cgroup_reset
,
1894 .read_u64
= mem_cgroup_read
,
1897 .name
= "memsw.limit_in_bytes",
1898 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_LIMIT
),
1899 .write_string
= mem_cgroup_write
,
1900 .read_u64
= mem_cgroup_read
,
1903 .name
= "memsw.failcnt",
1904 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_FAILCNT
),
1905 .trigger
= mem_cgroup_reset
,
1906 .read_u64
= mem_cgroup_read
,
1910 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1912 if (!do_swap_account
)
1914 return cgroup_add_files(cont
, ss
, memsw_cgroup_files
,
1915 ARRAY_SIZE(memsw_cgroup_files
));
1918 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1924 static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
1926 struct mem_cgroup_per_node
*pn
;
1927 struct mem_cgroup_per_zone
*mz
;
1929 int zone
, tmp
= node
;
1931 * This routine is called against possible nodes.
1932 * But it's BUG to call kmalloc() against offline node.
1934 * TODO: this routine can waste much memory for nodes which will
1935 * never be onlined. It's better to use memory hotplug callback
1938 if (!node_state(node
, N_NORMAL_MEMORY
))
1940 pn
= kmalloc_node(sizeof(*pn
), GFP_KERNEL
, tmp
);
1944 mem
->info
.nodeinfo
[node
] = pn
;
1945 memset(pn
, 0, sizeof(*pn
));
1947 for (zone
= 0; zone
< MAX_NR_ZONES
; zone
++) {
1948 mz
= &pn
->zoneinfo
[zone
];
1950 INIT_LIST_HEAD(&mz
->lists
[l
]);
1955 static void free_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
1957 kfree(mem
->info
.nodeinfo
[node
]);
1960 static int mem_cgroup_size(void)
1962 int cpustat_size
= nr_cpu_ids
* sizeof(struct mem_cgroup_stat_cpu
);
1963 return sizeof(struct mem_cgroup
) + cpustat_size
;
1966 static struct mem_cgroup
*mem_cgroup_alloc(void)
1968 struct mem_cgroup
*mem
;
1969 int size
= mem_cgroup_size();
1971 if (size
< PAGE_SIZE
)
1972 mem
= kmalloc(size
, GFP_KERNEL
);
1974 mem
= vmalloc(size
);
1977 memset(mem
, 0, size
);
1982 * At destroying mem_cgroup, references from swap_cgroup can remain.
1983 * (scanning all at force_empty is too costly...)
1985 * Instead of clearing all references at force_empty, we remember
1986 * the number of reference from swap_cgroup and free mem_cgroup when
1987 * it goes down to 0.
1989 * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and
1990 * entry which points to this memcg will be ignore at swapin.
1992 * Removal of cgroup itself succeeds regardless of refs from swap.
1995 static void mem_cgroup_free(struct mem_cgroup
*mem
)
1999 if (atomic_read(&mem
->refcnt
) > 0)
2003 for_each_node_state(node
, N_POSSIBLE
)
2004 free_mem_cgroup_per_zone_info(mem
, node
);
2006 if (mem_cgroup_size() < PAGE_SIZE
)
2012 static void mem_cgroup_get(struct mem_cgroup
*mem
)
2014 atomic_inc(&mem
->refcnt
);
2017 static void mem_cgroup_put(struct mem_cgroup
*mem
)
2019 if (atomic_dec_and_test(&mem
->refcnt
)) {
2022 mem_cgroup_free(mem
);
2027 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2028 static void __init
enable_swap_cgroup(void)
2030 if (!mem_cgroup_disabled() && really_do_swap_account
)
2031 do_swap_account
= 1;
2034 static void __init
enable_swap_cgroup(void)
2039 static struct cgroup_subsys_state
*
2040 mem_cgroup_create(struct cgroup_subsys
*ss
, struct cgroup
*cont
)
2042 struct mem_cgroup
*mem
, *parent
;
2045 mem
= mem_cgroup_alloc();
2047 return ERR_PTR(-ENOMEM
);
2049 for_each_node_state(node
, N_POSSIBLE
)
2050 if (alloc_mem_cgroup_per_zone_info(mem
, node
))
2053 if (cont
->parent
== NULL
) {
2054 enable_swap_cgroup();
2057 parent
= mem_cgroup_from_cont(cont
->parent
);
2058 mem
->use_hierarchy
= parent
->use_hierarchy
;
2061 if (parent
&& parent
->use_hierarchy
) {
2062 res_counter_init(&mem
->res
, &parent
->res
);
2063 res_counter_init(&mem
->memsw
, &parent
->memsw
);
2065 res_counter_init(&mem
->res
, NULL
);
2066 res_counter_init(&mem
->memsw
, NULL
);
2068 mem_cgroup_set_inactive_ratio(mem
);
2069 mem
->last_scanned_child
= NULL
;
2073 for_each_node_state(node
, N_POSSIBLE
)
2074 free_mem_cgroup_per_zone_info(mem
, node
);
2075 mem_cgroup_free(mem
);
2076 return ERR_PTR(-ENOMEM
);
2079 static void mem_cgroup_pre_destroy(struct cgroup_subsys
*ss
,
2080 struct cgroup
*cont
)
2082 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
2084 mem_cgroup_force_empty(mem
, false);
2087 static void mem_cgroup_destroy(struct cgroup_subsys
*ss
,
2088 struct cgroup
*cont
)
2090 mem_cgroup_free(mem_cgroup_from_cont(cont
));
2093 static int mem_cgroup_populate(struct cgroup_subsys
*ss
,
2094 struct cgroup
*cont
)
2098 ret
= cgroup_add_files(cont
, ss
, mem_cgroup_files
,
2099 ARRAY_SIZE(mem_cgroup_files
));
2102 ret
= register_memsw_files(cont
, ss
);
2106 static void mem_cgroup_move_task(struct cgroup_subsys
*ss
,
2107 struct cgroup
*cont
,
2108 struct cgroup
*old_cont
,
2109 struct task_struct
*p
)
2112 * FIXME: It's better to move charges of this process from old
2113 * memcg to new memcg. But it's just on TODO-List now.
2117 struct cgroup_subsys mem_cgroup_subsys
= {
2119 .subsys_id
= mem_cgroup_subsys_id
,
2120 .create
= mem_cgroup_create
,
2121 .pre_destroy
= mem_cgroup_pre_destroy
,
2122 .destroy
= mem_cgroup_destroy
,
2123 .populate
= mem_cgroup_populate
,
2124 .attach
= mem_cgroup_move_task
,
2128 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2130 static int __init
disable_swap_account(char *s
)
2132 really_do_swap_account
= 0;
2135 __setup("noswapaccount", disable_swap_account
);