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 /* Macro for accessing counter */
108 #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)])
110 struct mem_cgroup_per_node
{
111 struct mem_cgroup_per_zone zoneinfo
[MAX_NR_ZONES
];
114 struct mem_cgroup_lru_info
{
115 struct mem_cgroup_per_node
*nodeinfo
[MAX_NUMNODES
];
119 * The memory controller data structure. The memory controller controls both
120 * page cache and RSS per cgroup. We would eventually like to provide
121 * statistics based on the statistics developed by Rik Van Riel for clock-pro,
122 * to help the administrator determine what knobs to tune.
124 * TODO: Add a water mark for the memory controller. Reclaim will begin when
125 * we hit the water mark. May be even add a low water mark, such that
126 * no reclaim occurs from a cgroup at it's low water mark, this is
127 * a feature that will be implemented much later in the future.
130 struct cgroup_subsys_state css
;
132 * the counter to account for memory usage
134 struct res_counter res
;
136 * the counter to account for mem+swap usage.
138 struct res_counter memsw
;
140 * Per cgroup active and inactive list, similar to the
141 * per zone LRU lists.
143 struct mem_cgroup_lru_info info
;
145 int prev_priority
; /* for recording reclaim priority */
148 * While reclaiming in a hiearchy, we cache the last child we
149 * reclaimed from. Protected by cgroup_lock()
151 struct mem_cgroup
*last_scanned_child
;
153 * Should the accounting and control be hierarchical, per subtree?
160 * statistics. This must be placed at the end of memcg.
162 struct mem_cgroup_stat stat
;
166 MEM_CGROUP_CHARGE_TYPE_CACHE
= 0,
167 MEM_CGROUP_CHARGE_TYPE_MAPPED
,
168 MEM_CGROUP_CHARGE_TYPE_SHMEM
, /* used by page migration of shmem */
169 MEM_CGROUP_CHARGE_TYPE_FORCE
, /* used by force_empty */
170 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
, /* for accounting swapcache */
174 /* only for here (for easy reading.) */
175 #define PCGF_CACHE (1UL << PCG_CACHE)
176 #define PCGF_USED (1UL << PCG_USED)
177 #define PCGF_LOCK (1UL << PCG_LOCK)
178 static const unsigned long
179 pcg_default_flags
[NR_CHARGE_TYPE
] = {
180 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* File Cache */
181 PCGF_USED
| PCGF_LOCK
, /* Anon */
182 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* Shmem */
187 /* for encoding cft->private value on file */
190 #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
191 #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
192 #define MEMFILE_ATTR(val) ((val) & 0xffff)
194 static void mem_cgroup_get(struct mem_cgroup
*mem
);
195 static void mem_cgroup_put(struct mem_cgroup
*mem
);
197 static void mem_cgroup_charge_statistics(struct mem_cgroup
*mem
,
198 struct page_cgroup
*pc
,
201 int val
= (charge
)? 1 : -1;
202 struct mem_cgroup_stat
*stat
= &mem
->stat
;
203 struct mem_cgroup_stat_cpu
*cpustat
;
206 cpustat
= &stat
->cpustat
[cpu
];
207 if (PageCgroupCache(pc
))
208 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_CACHE
, val
);
210 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_RSS
, val
);
213 __mem_cgroup_stat_add_safe(cpustat
,
214 MEM_CGROUP_STAT_PGPGIN_COUNT
, 1);
216 __mem_cgroup_stat_add_safe(cpustat
,
217 MEM_CGROUP_STAT_PGPGOUT_COUNT
, 1);
221 static struct mem_cgroup_per_zone
*
222 mem_cgroup_zoneinfo(struct mem_cgroup
*mem
, int nid
, int zid
)
224 return &mem
->info
.nodeinfo
[nid
]->zoneinfo
[zid
];
227 static struct mem_cgroup_per_zone
*
228 page_cgroup_zoneinfo(struct page_cgroup
*pc
)
230 struct mem_cgroup
*mem
= pc
->mem_cgroup
;
231 int nid
= page_cgroup_nid(pc
);
232 int zid
= page_cgroup_zid(pc
);
234 return mem_cgroup_zoneinfo(mem
, nid
, zid
);
237 static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup
*mem
,
241 struct mem_cgroup_per_zone
*mz
;
244 for_each_online_node(nid
)
245 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
246 mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
247 total
+= MEM_CGROUP_ZSTAT(mz
, idx
);
252 static struct mem_cgroup
*mem_cgroup_from_cont(struct cgroup
*cont
)
254 return container_of(cgroup_subsys_state(cont
,
255 mem_cgroup_subsys_id
), struct mem_cgroup
,
259 struct mem_cgroup
*mem_cgroup_from_task(struct task_struct
*p
)
262 * mm_update_next_owner() may clear mm->owner to NULL
263 * if it races with swapoff, page migration, etc.
264 * So this can be called with p == NULL.
269 return container_of(task_subsys_state(p
, mem_cgroup_subsys_id
),
270 struct mem_cgroup
, css
);
274 * Following LRU functions are allowed to be used without PCG_LOCK.
275 * Operations are called by routine of global LRU independently from memcg.
276 * What we have to take care of here is validness of pc->mem_cgroup.
278 * Changes to pc->mem_cgroup happens when
281 * In typical case, "charge" is done before add-to-lru. Exception is SwapCache.
282 * It is added to LRU before charge.
283 * If PCG_USED bit is not set, page_cgroup is not added to this private LRU.
284 * When moving account, the page is not on LRU. It's isolated.
287 void mem_cgroup_del_lru_list(struct page
*page
, enum lru_list lru
)
289 struct page_cgroup
*pc
;
290 struct mem_cgroup
*mem
;
291 struct mem_cgroup_per_zone
*mz
;
293 if (mem_cgroup_disabled())
295 pc
= lookup_page_cgroup(page
);
296 /* can happen while we handle swapcache. */
297 if (list_empty(&pc
->lru
))
299 mz
= page_cgroup_zoneinfo(pc
);
300 mem
= pc
->mem_cgroup
;
301 MEM_CGROUP_ZSTAT(mz
, lru
) -= 1;
302 list_del_init(&pc
->lru
);
306 void mem_cgroup_del_lru(struct page
*page
)
308 mem_cgroup_del_lru_list(page
, page_lru(page
));
311 void mem_cgroup_rotate_lru_list(struct page
*page
, enum lru_list lru
)
313 struct mem_cgroup_per_zone
*mz
;
314 struct page_cgroup
*pc
;
316 if (mem_cgroup_disabled())
319 pc
= lookup_page_cgroup(page
);
321 /* unused page is not rotated. */
322 if (!PageCgroupUsed(pc
))
324 mz
= page_cgroup_zoneinfo(pc
);
325 list_move(&pc
->lru
, &mz
->lists
[lru
]);
328 void mem_cgroup_add_lru_list(struct page
*page
, enum lru_list lru
)
330 struct page_cgroup
*pc
;
331 struct mem_cgroup_per_zone
*mz
;
333 if (mem_cgroup_disabled())
335 pc
= lookup_page_cgroup(page
);
336 /* barrier to sync with "charge" */
338 if (!PageCgroupUsed(pc
))
341 mz
= page_cgroup_zoneinfo(pc
);
342 MEM_CGROUP_ZSTAT(mz
, lru
) += 1;
343 list_add(&pc
->lru
, &mz
->lists
[lru
]);
346 * To add swapcache into LRU. Be careful to all this function.
347 * zone->lru_lock shouldn't be held and irq must not be disabled.
349 static void mem_cgroup_lru_fixup(struct page
*page
)
351 if (!isolate_lru_page(page
))
352 putback_lru_page(page
);
355 void mem_cgroup_move_lists(struct page
*page
,
356 enum lru_list from
, enum lru_list to
)
358 if (mem_cgroup_disabled())
360 mem_cgroup_del_lru_list(page
, from
);
361 mem_cgroup_add_lru_list(page
, to
);
364 int task_in_mem_cgroup(struct task_struct
*task
, const struct mem_cgroup
*mem
)
369 ret
= task
->mm
&& mm_match_cgroup(task
->mm
, mem
);
375 * Calculate mapped_ratio under memory controller. This will be used in
376 * vmscan.c for deteremining we have to reclaim mapped pages.
378 int mem_cgroup_calc_mapped_ratio(struct mem_cgroup
*mem
)
383 * usage is recorded in bytes. But, here, we assume the number of
384 * physical pages can be represented by "long" on any arch.
386 total
= (long) (mem
->res
.usage
>> PAGE_SHIFT
) + 1L;
387 rss
= (long)mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_RSS
);
388 return (int)((rss
* 100L) / total
);
392 * prev_priority control...this will be used in memory reclaim path.
394 int mem_cgroup_get_reclaim_priority(struct mem_cgroup
*mem
)
396 return mem
->prev_priority
;
399 void mem_cgroup_note_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
401 if (priority
< mem
->prev_priority
)
402 mem
->prev_priority
= priority
;
405 void mem_cgroup_record_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
407 mem
->prev_priority
= priority
;
411 * Calculate # of pages to be scanned in this priority/zone.
414 * priority starts from "DEF_PRIORITY" and decremented in each loop.
415 * (see include/linux/mmzone.h)
418 long mem_cgroup_calc_reclaim(struct mem_cgroup
*mem
, struct zone
*zone
,
419 int priority
, enum lru_list lru
)
422 int nid
= zone
->zone_pgdat
->node_id
;
423 int zid
= zone_idx(zone
);
424 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
426 nr_pages
= MEM_CGROUP_ZSTAT(mz
, lru
);
428 return (nr_pages
>> priority
);
431 unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan
,
432 struct list_head
*dst
,
433 unsigned long *scanned
, int order
,
434 int mode
, struct zone
*z
,
435 struct mem_cgroup
*mem_cont
,
436 int active
, int file
)
438 unsigned long nr_taken
= 0;
442 struct list_head
*src
;
443 struct page_cgroup
*pc
, *tmp
;
444 int nid
= z
->zone_pgdat
->node_id
;
445 int zid
= zone_idx(z
);
446 struct mem_cgroup_per_zone
*mz
;
447 int lru
= LRU_FILE
* !!file
+ !!active
;
450 mz
= mem_cgroup_zoneinfo(mem_cont
, nid
, zid
);
451 src
= &mz
->lists
[lru
];
454 list_for_each_entry_safe_reverse(pc
, tmp
, src
, lru
) {
455 if (scan
>= nr_to_scan
)
459 if (unlikely(!PageCgroupUsed(pc
)))
461 if (unlikely(!PageLRU(page
)))
465 if (__isolate_lru_page(page
, mode
, file
) == 0) {
466 list_move(&page
->lru
, dst
);
475 #define mem_cgroup_from_res_counter(counter, member) \
476 container_of(counter, struct mem_cgroup, member)
479 * This routine finds the DFS walk successor. This routine should be
480 * called with cgroup_mutex held
482 static struct mem_cgroup
*
483 mem_cgroup_get_next_node(struct mem_cgroup
*curr
, struct mem_cgroup
*root_mem
)
485 struct cgroup
*cgroup
, *curr_cgroup
, *root_cgroup
;
487 curr_cgroup
= curr
->css
.cgroup
;
488 root_cgroup
= root_mem
->css
.cgroup
;
490 if (!list_empty(&curr_cgroup
->children
)) {
492 * Walk down to children
494 mem_cgroup_put(curr
);
495 cgroup
= list_entry(curr_cgroup
->children
.next
,
496 struct cgroup
, sibling
);
497 curr
= mem_cgroup_from_cont(cgroup
);
498 mem_cgroup_get(curr
);
503 if (curr_cgroup
== root_cgroup
) {
504 mem_cgroup_put(curr
);
506 mem_cgroup_get(curr
);
513 if (curr_cgroup
->sibling
.next
!= &curr_cgroup
->parent
->children
) {
514 mem_cgroup_put(curr
);
515 cgroup
= list_entry(curr_cgroup
->sibling
.next
, struct cgroup
,
517 curr
= mem_cgroup_from_cont(cgroup
);
518 mem_cgroup_get(curr
);
523 * Go up to next parent and next parent's sibling if need be
525 curr_cgroup
= curr_cgroup
->parent
;
529 root_mem
->last_scanned_child
= curr
;
534 * Visit the first child (need not be the first child as per the ordering
535 * of the cgroup list, since we track last_scanned_child) of @mem and use
536 * that to reclaim free pages from.
538 static struct mem_cgroup
*
539 mem_cgroup_get_first_node(struct mem_cgroup
*root_mem
)
541 struct cgroup
*cgroup
;
542 struct mem_cgroup
*ret
;
543 bool obsolete
= (root_mem
->last_scanned_child
&&
544 root_mem
->last_scanned_child
->obsolete
);
547 * Scan all children under the mem_cgroup mem
550 if (list_empty(&root_mem
->css
.cgroup
->children
)) {
555 if (!root_mem
->last_scanned_child
|| obsolete
) {
558 mem_cgroup_put(root_mem
->last_scanned_child
);
560 cgroup
= list_first_entry(&root_mem
->css
.cgroup
->children
,
561 struct cgroup
, sibling
);
562 ret
= mem_cgroup_from_cont(cgroup
);
565 ret
= mem_cgroup_get_next_node(root_mem
->last_scanned_child
,
569 root_mem
->last_scanned_child
= ret
;
575 * Dance down the hierarchy if needed to reclaim memory. We remember the
576 * last child we reclaimed from, so that we don't end up penalizing
577 * one child extensively based on its position in the children list.
579 * root_mem is the original ancestor that we've been reclaim from.
581 static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup
*root_mem
,
582 gfp_t gfp_mask
, bool noswap
)
584 struct mem_cgroup
*next_mem
;
588 * Reclaim unconditionally and don't check for return value.
589 * We need to reclaim in the current group and down the tree.
590 * One might think about checking for children before reclaiming,
591 * but there might be left over accounting, even after children
594 ret
= try_to_free_mem_cgroup_pages(root_mem
, gfp_mask
, noswap
);
595 if (res_counter_check_under_limit(&root_mem
->res
))
598 next_mem
= mem_cgroup_get_first_node(root_mem
);
600 while (next_mem
!= root_mem
) {
601 if (next_mem
->obsolete
) {
602 mem_cgroup_put(next_mem
);
604 next_mem
= mem_cgroup_get_first_node(root_mem
);
608 ret
= try_to_free_mem_cgroup_pages(next_mem
, gfp_mask
, noswap
);
609 if (res_counter_check_under_limit(&root_mem
->res
))
612 next_mem
= mem_cgroup_get_next_node(next_mem
, root_mem
);
619 * Unlike exported interface, "oom" parameter is added. if oom==true,
620 * oom-killer can be invoked.
622 static int __mem_cgroup_try_charge(struct mm_struct
*mm
,
623 gfp_t gfp_mask
, struct mem_cgroup
**memcg
,
626 struct mem_cgroup
*mem
, *mem_over_limit
;
627 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
628 struct res_counter
*fail_res
;
630 * We always charge the cgroup the mm_struct belongs to.
631 * The mm_struct's mem_cgroup changes on task migration if the
632 * thread group leader migrates. It's possible that mm is not
633 * set, if so charge the init_mm (happens for pagecache usage).
635 if (likely(!*memcg
)) {
637 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
638 if (unlikely(!mem
)) {
643 * For every charge from the cgroup, increment reference count
657 ret
= res_counter_charge(&mem
->res
, PAGE_SIZE
, &fail_res
);
659 if (!do_swap_account
)
661 ret
= res_counter_charge(&mem
->memsw
, PAGE_SIZE
,
665 /* mem+swap counter fails */
666 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
668 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
671 /* mem counter fails */
672 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
675 if (!(gfp_mask
& __GFP_WAIT
))
678 ret
= mem_cgroup_hierarchical_reclaim(mem_over_limit
, gfp_mask
,
682 * try_to_free_mem_cgroup_pages() might not give us a full
683 * picture of reclaim. Some pages are reclaimed and might be
684 * moved to swap cache or just unmapped from the cgroup.
685 * Check the limit again to see if the reclaim reduced the
686 * current usage of the cgroup before giving up
689 if (!do_swap_account
&&
690 res_counter_check_under_limit(&mem
->res
))
692 if (do_swap_account
&&
693 res_counter_check_under_limit(&mem
->memsw
))
698 mem_cgroup_out_of_memory(mem
, gfp_mask
);
709 * mem_cgroup_try_charge - get charge of PAGE_SIZE.
710 * @mm: an mm_struct which is charged against. (when *memcg is NULL)
711 * @gfp_mask: gfp_mask for reclaim.
712 * @memcg: a pointer to memory cgroup which is charged against.
714 * charge against memory cgroup pointed by *memcg. if *memcg == NULL, estimated
715 * memory cgroup from @mm is got and stored in *memcg.
717 * Returns 0 if success. -ENOMEM at failure.
718 * This call can invoke OOM-Killer.
721 int mem_cgroup_try_charge(struct mm_struct
*mm
,
722 gfp_t mask
, struct mem_cgroup
**memcg
)
724 return __mem_cgroup_try_charge(mm
, mask
, memcg
, true);
728 * commit a charge got by mem_cgroup_try_charge() and makes page_cgroup to be
729 * USED state. If already USED, uncharge and return.
732 static void __mem_cgroup_commit_charge(struct mem_cgroup
*mem
,
733 struct page_cgroup
*pc
,
734 enum charge_type ctype
)
736 /* try_charge() can return NULL to *memcg, taking care of it. */
740 lock_page_cgroup(pc
);
741 if (unlikely(PageCgroupUsed(pc
))) {
742 unlock_page_cgroup(pc
);
743 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
745 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
749 pc
->mem_cgroup
= mem
;
751 pc
->flags
= pcg_default_flags
[ctype
];
753 mem_cgroup_charge_statistics(mem
, pc
, true);
755 unlock_page_cgroup(pc
);
759 * mem_cgroup_move_account - move account of the page
760 * @pc: page_cgroup of the page.
761 * @from: mem_cgroup which the page is moved from.
762 * @to: mem_cgroup which the page is moved to. @from != @to.
764 * The caller must confirm following.
765 * - page is not on LRU (isolate_page() is useful.)
767 * returns 0 at success,
768 * returns -EBUSY when lock is busy or "pc" is unstable.
770 * This function does "uncharge" from old cgroup but doesn't do "charge" to
771 * new cgroup. It should be done by a caller.
774 static int mem_cgroup_move_account(struct page_cgroup
*pc
,
775 struct mem_cgroup
*from
, struct mem_cgroup
*to
)
777 struct mem_cgroup_per_zone
*from_mz
, *to_mz
;
781 VM_BUG_ON(from
== to
);
782 VM_BUG_ON(PageLRU(pc
->page
));
784 nid
= page_cgroup_nid(pc
);
785 zid
= page_cgroup_zid(pc
);
786 from_mz
= mem_cgroup_zoneinfo(from
, nid
, zid
);
787 to_mz
= mem_cgroup_zoneinfo(to
, nid
, zid
);
789 if (!trylock_page_cgroup(pc
))
792 if (!PageCgroupUsed(pc
))
795 if (pc
->mem_cgroup
!= from
)
799 res_counter_uncharge(&from
->res
, PAGE_SIZE
);
800 mem_cgroup_charge_statistics(from
, pc
, false);
802 res_counter_uncharge(&from
->memsw
, PAGE_SIZE
);
804 mem_cgroup_charge_statistics(to
, pc
, true);
808 unlock_page_cgroup(pc
);
813 * move charges to its parent.
816 static int mem_cgroup_move_parent(struct page_cgroup
*pc
,
817 struct mem_cgroup
*child
,
820 struct page
*page
= pc
->page
;
821 struct cgroup
*cg
= child
->css
.cgroup
;
822 struct cgroup
*pcg
= cg
->parent
;
823 struct mem_cgroup
*parent
;
831 parent
= mem_cgroup_from_cont(pcg
);
834 ret
= __mem_cgroup_try_charge(NULL
, gfp_mask
, &parent
, false);
838 if (!get_page_unless_zero(page
))
841 ret
= isolate_lru_page(page
);
846 ret
= mem_cgroup_move_account(pc
, child
, parent
);
848 /* drop extra refcnt by try_charge() (move_account increment one) */
849 css_put(&parent
->css
);
850 putback_lru_page(page
);
855 /* uncharge if move fails */
857 res_counter_uncharge(&parent
->res
, PAGE_SIZE
);
859 res_counter_uncharge(&parent
->memsw
, PAGE_SIZE
);
865 * Charge the memory controller for page usage.
867 * 0 if the charge was successful
868 * < 0 if the cgroup is over its limit
870 static int mem_cgroup_charge_common(struct page
*page
, struct mm_struct
*mm
,
871 gfp_t gfp_mask
, enum charge_type ctype
,
872 struct mem_cgroup
*memcg
)
874 struct mem_cgroup
*mem
;
875 struct page_cgroup
*pc
;
878 pc
= lookup_page_cgroup(page
);
879 /* can happen at boot */
885 ret
= __mem_cgroup_try_charge(mm
, gfp_mask
, &mem
, true);
889 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
893 int mem_cgroup_newpage_charge(struct page
*page
,
894 struct mm_struct
*mm
, gfp_t gfp_mask
)
896 if (mem_cgroup_disabled())
898 if (PageCompound(page
))
901 * If already mapped, we don't have to account.
902 * If page cache, page->mapping has address_space.
903 * But page->mapping may have out-of-use anon_vma pointer,
904 * detecit it by PageAnon() check. newly-mapped-anon's page->mapping
907 if (page_mapped(page
) || (page
->mapping
&& !PageAnon(page
)))
911 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
912 MEM_CGROUP_CHARGE_TYPE_MAPPED
, NULL
);
915 int mem_cgroup_cache_charge(struct page
*page
, struct mm_struct
*mm
,
918 if (mem_cgroup_disabled())
920 if (PageCompound(page
))
923 * Corner case handling. This is called from add_to_page_cache()
924 * in usual. But some FS (shmem) precharges this page before calling it
925 * and call add_to_page_cache() with GFP_NOWAIT.
927 * For GFP_NOWAIT case, the page may be pre-charged before calling
928 * add_to_page_cache(). (See shmem.c) check it here and avoid to call
929 * charge twice. (It works but has to pay a bit larger cost.)
931 if (!(gfp_mask
& __GFP_WAIT
)) {
932 struct page_cgroup
*pc
;
935 pc
= lookup_page_cgroup(page
);
938 lock_page_cgroup(pc
);
939 if (PageCgroupUsed(pc
)) {
940 unlock_page_cgroup(pc
);
943 unlock_page_cgroup(pc
);
949 if (page_is_file_cache(page
))
950 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
951 MEM_CGROUP_CHARGE_TYPE_CACHE
, NULL
);
953 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
954 MEM_CGROUP_CHARGE_TYPE_SHMEM
, NULL
);
957 int mem_cgroup_try_charge_swapin(struct mm_struct
*mm
,
959 gfp_t mask
, struct mem_cgroup
**ptr
)
961 struct mem_cgroup
*mem
;
964 if (mem_cgroup_disabled())
967 if (!do_swap_account
)
971 * A racing thread's fault, or swapoff, may have already updated
972 * the pte, and even removed page from swap cache: return success
973 * to go on to do_swap_page()'s pte_same() test, which should fail.
975 if (!PageSwapCache(page
))
978 ent
.val
= page_private(page
);
980 mem
= lookup_swap_cgroup(ent
);
981 if (!mem
|| mem
->obsolete
)
984 return __mem_cgroup_try_charge(NULL
, mask
, ptr
, true);
988 return __mem_cgroup_try_charge(mm
, mask
, ptr
, true);
993 int mem_cgroup_cache_charge_swapin(struct page
*page
,
994 struct mm_struct
*mm
, gfp_t mask
, bool locked
)
998 if (mem_cgroup_disabled())
1005 * If not locked, the page can be dropped from SwapCache until
1008 if (PageSwapCache(page
)) {
1009 struct mem_cgroup
*mem
= NULL
;
1012 ent
.val
= page_private(page
);
1013 if (do_swap_account
) {
1014 mem
= lookup_swap_cgroup(ent
);
1015 if (mem
&& mem
->obsolete
)
1020 ret
= mem_cgroup_charge_common(page
, mm
, mask
,
1021 MEM_CGROUP_CHARGE_TYPE_SHMEM
, mem
);
1023 if (!ret
&& do_swap_account
) {
1024 /* avoid double counting */
1025 mem
= swap_cgroup_record(ent
, NULL
);
1027 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1028 mem_cgroup_put(mem
);
1034 /* add this page(page_cgroup) to the LRU we want. */
1035 mem_cgroup_lru_fixup(page
);
1041 void mem_cgroup_commit_charge_swapin(struct page
*page
, struct mem_cgroup
*ptr
)
1043 struct page_cgroup
*pc
;
1045 if (mem_cgroup_disabled())
1049 pc
= lookup_page_cgroup(page
);
1050 __mem_cgroup_commit_charge(ptr
, pc
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1052 * Now swap is on-memory. This means this page may be
1053 * counted both as mem and swap....double count.
1054 * Fix it by uncharging from memsw. This SwapCache is stable
1055 * because we're still under lock_page().
1057 if (do_swap_account
) {
1058 swp_entry_t ent
= {.val
= page_private(page
)};
1059 struct mem_cgroup
*memcg
;
1060 memcg
= swap_cgroup_record(ent
, NULL
);
1062 /* If memcg is obsolete, memcg can be != ptr */
1063 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1064 mem_cgroup_put(memcg
);
1068 /* add this page(page_cgroup) to the LRU we want. */
1069 mem_cgroup_lru_fixup(page
);
1072 void mem_cgroup_cancel_charge_swapin(struct mem_cgroup
*mem
)
1074 if (mem_cgroup_disabled())
1078 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1079 if (do_swap_account
)
1080 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1086 * uncharge if !page_mapped(page)
1088 static struct mem_cgroup
*
1089 __mem_cgroup_uncharge_common(struct page
*page
, enum charge_type ctype
)
1091 struct page_cgroup
*pc
;
1092 struct mem_cgroup
*mem
= NULL
;
1093 struct mem_cgroup_per_zone
*mz
;
1095 if (mem_cgroup_disabled())
1098 if (PageSwapCache(page
))
1102 * Check if our page_cgroup is valid
1104 pc
= lookup_page_cgroup(page
);
1105 if (unlikely(!pc
|| !PageCgroupUsed(pc
)))
1108 lock_page_cgroup(pc
);
1110 mem
= pc
->mem_cgroup
;
1112 if (!PageCgroupUsed(pc
))
1116 case MEM_CGROUP_CHARGE_TYPE_MAPPED
:
1117 if (page_mapped(page
))
1120 case MEM_CGROUP_CHARGE_TYPE_SWAPOUT
:
1121 if (!PageAnon(page
)) { /* Shared memory */
1122 if (page
->mapping
&& !page_is_file_cache(page
))
1124 } else if (page_mapped(page
)) /* Anon */
1131 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1132 if (do_swap_account
&& (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
))
1133 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1135 mem_cgroup_charge_statistics(mem
, pc
, false);
1136 ClearPageCgroupUsed(pc
);
1138 mz
= page_cgroup_zoneinfo(pc
);
1139 unlock_page_cgroup(pc
);
1146 unlock_page_cgroup(pc
);
1150 void mem_cgroup_uncharge_page(struct page
*page
)
1153 if (page_mapped(page
))
1155 if (page
->mapping
&& !PageAnon(page
))
1157 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1160 void mem_cgroup_uncharge_cache_page(struct page
*page
)
1162 VM_BUG_ON(page_mapped(page
));
1163 VM_BUG_ON(page
->mapping
);
1164 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_CACHE
);
1168 * called from __delete_from_swap_cache() and drop "page" account.
1169 * memcg information is recorded to swap_cgroup of "ent"
1171 void mem_cgroup_uncharge_swapcache(struct page
*page
, swp_entry_t ent
)
1173 struct mem_cgroup
*memcg
;
1175 memcg
= __mem_cgroup_uncharge_common(page
,
1176 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
);
1177 /* record memcg information */
1178 if (do_swap_account
&& memcg
) {
1179 swap_cgroup_record(ent
, memcg
);
1180 mem_cgroup_get(memcg
);
1184 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1186 * called from swap_entry_free(). remove record in swap_cgroup and
1187 * uncharge "memsw" account.
1189 void mem_cgroup_uncharge_swap(swp_entry_t ent
)
1191 struct mem_cgroup
*memcg
;
1193 if (!do_swap_account
)
1196 memcg
= swap_cgroup_record(ent
, NULL
);
1198 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1199 mem_cgroup_put(memcg
);
1205 * Before starting migration, account PAGE_SIZE to mem_cgroup that the old
1208 int mem_cgroup_prepare_migration(struct page
*page
, struct mem_cgroup
**ptr
)
1210 struct page_cgroup
*pc
;
1211 struct mem_cgroup
*mem
= NULL
;
1214 if (mem_cgroup_disabled())
1217 pc
= lookup_page_cgroup(page
);
1218 lock_page_cgroup(pc
);
1219 if (PageCgroupUsed(pc
)) {
1220 mem
= pc
->mem_cgroup
;
1223 unlock_page_cgroup(pc
);
1226 ret
= mem_cgroup_try_charge(NULL
, GFP_HIGHUSER_MOVABLE
, &mem
);
1233 /* remove redundant charge if migration failed*/
1234 void mem_cgroup_end_migration(struct mem_cgroup
*mem
,
1235 struct page
*oldpage
, struct page
*newpage
)
1237 struct page
*target
, *unused
;
1238 struct page_cgroup
*pc
;
1239 enum charge_type ctype
;
1244 /* at migration success, oldpage->mapping is NULL. */
1245 if (oldpage
->mapping
) {
1253 if (PageAnon(target
))
1254 ctype
= MEM_CGROUP_CHARGE_TYPE_MAPPED
;
1255 else if (page_is_file_cache(target
))
1256 ctype
= MEM_CGROUP_CHARGE_TYPE_CACHE
;
1258 ctype
= MEM_CGROUP_CHARGE_TYPE_SHMEM
;
1260 /* unused page is not on radix-tree now. */
1262 __mem_cgroup_uncharge_common(unused
, ctype
);
1264 pc
= lookup_page_cgroup(target
);
1266 * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
1267 * So, double-counting is effectively avoided.
1269 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
1272 * Both of oldpage and newpage are still under lock_page().
1273 * Then, we don't have to care about race in radix-tree.
1274 * But we have to be careful that this page is unmapped or not.
1276 * There is a case for !page_mapped(). At the start of
1277 * migration, oldpage was mapped. But now, it's zapped.
1278 * But we know *target* page is not freed/reused under us.
1279 * mem_cgroup_uncharge_page() does all necessary checks.
1281 if (ctype
== MEM_CGROUP_CHARGE_TYPE_MAPPED
)
1282 mem_cgroup_uncharge_page(target
);
1286 * A call to try to shrink memory usage under specified resource controller.
1287 * This is typically used for page reclaiming for shmem for reducing side
1288 * effect of page allocation from shmem, which is used by some mem_cgroup.
1290 int mem_cgroup_shrink_usage(struct mm_struct
*mm
, gfp_t gfp_mask
)
1292 struct mem_cgroup
*mem
;
1294 int retry
= MEM_CGROUP_RECLAIM_RETRIES
;
1296 if (mem_cgroup_disabled())
1302 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
1303 if (unlikely(!mem
)) {
1311 progress
= try_to_free_mem_cgroup_pages(mem
, gfp_mask
, true);
1312 progress
+= res_counter_check_under_limit(&mem
->res
);
1313 } while (!progress
&& --retry
);
1321 static DEFINE_MUTEX(set_limit_mutex
);
1323 static int mem_cgroup_resize_limit(struct mem_cgroup
*memcg
,
1324 unsigned long long val
)
1327 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1332 while (retry_count
) {
1333 if (signal_pending(current
)) {
1338 * Rather than hide all in some function, I do this in
1339 * open coded manner. You see what this really does.
1340 * We have to guarantee mem->res.limit < mem->memsw.limit.
1342 mutex_lock(&set_limit_mutex
);
1343 memswlimit
= res_counter_read_u64(&memcg
->memsw
, RES_LIMIT
);
1344 if (memswlimit
< val
) {
1346 mutex_unlock(&set_limit_mutex
);
1349 ret
= res_counter_set_limit(&memcg
->res
, val
);
1350 mutex_unlock(&set_limit_mutex
);
1355 progress
= try_to_free_mem_cgroup_pages(memcg
,
1356 GFP_HIGHUSER_MOVABLE
, false);
1357 if (!progress
) retry_count
--;
1362 int mem_cgroup_resize_memsw_limit(struct mem_cgroup
*memcg
,
1363 unsigned long long val
)
1365 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1366 u64 memlimit
, oldusage
, curusage
;
1369 if (!do_swap_account
)
1372 while (retry_count
) {
1373 if (signal_pending(current
)) {
1378 * Rather than hide all in some function, I do this in
1379 * open coded manner. You see what this really does.
1380 * We have to guarantee mem->res.limit < mem->memsw.limit.
1382 mutex_lock(&set_limit_mutex
);
1383 memlimit
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
);
1384 if (memlimit
> val
) {
1386 mutex_unlock(&set_limit_mutex
);
1389 ret
= res_counter_set_limit(&memcg
->memsw
, val
);
1390 mutex_unlock(&set_limit_mutex
);
1395 oldusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1396 try_to_free_mem_cgroup_pages(memcg
, GFP_HIGHUSER_MOVABLE
, true);
1397 curusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1398 if (curusage
>= oldusage
)
1405 * This routine traverse page_cgroup in given list and drop them all.
1406 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
1408 static int mem_cgroup_force_empty_list(struct mem_cgroup
*mem
,
1409 int node
, int zid
, enum lru_list lru
)
1412 struct mem_cgroup_per_zone
*mz
;
1413 struct page_cgroup
*pc
, *busy
;
1414 unsigned long flags
, loop
;
1415 struct list_head
*list
;
1418 zone
= &NODE_DATA(node
)->node_zones
[zid
];
1419 mz
= mem_cgroup_zoneinfo(mem
, node
, zid
);
1420 list
= &mz
->lists
[lru
];
1422 loop
= MEM_CGROUP_ZSTAT(mz
, lru
);
1423 /* give some margin against EBUSY etc...*/
1428 spin_lock_irqsave(&zone
->lru_lock
, flags
);
1429 if (list_empty(list
)) {
1430 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1433 pc
= list_entry(list
->prev
, struct page_cgroup
, lru
);
1435 list_move(&pc
->lru
, list
);
1437 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1440 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1442 ret
= mem_cgroup_move_parent(pc
, mem
, GFP_HIGHUSER_MOVABLE
);
1446 if (ret
== -EBUSY
|| ret
== -EINVAL
) {
1447 /* found lock contention or "pc" is obsolete. */
1454 if (!ret
&& !list_empty(list
))
1460 * make mem_cgroup's charge to be 0 if there is no task.
1461 * This enables deleting this mem_cgroup.
1463 static int mem_cgroup_force_empty(struct mem_cgroup
*mem
, bool free_all
)
1466 int node
, zid
, shrink
;
1467 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
1468 struct cgroup
*cgrp
= mem
->css
.cgroup
;
1473 /* should free all ? */
1477 while (mem
->res
.usage
> 0) {
1479 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
))
1482 if (signal_pending(current
))
1484 /* This is for making all *used* pages to be on LRU. */
1485 lru_add_drain_all();
1487 for_each_node_state(node
, N_POSSIBLE
) {
1488 for (zid
= 0; !ret
&& zid
< MAX_NR_ZONES
; zid
++) {
1491 ret
= mem_cgroup_force_empty_list(mem
,
1500 /* it seems parent cgroup doesn't have enough mem */
1511 /* returns EBUSY if there is a task or if we come here twice. */
1512 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
) || shrink
) {
1516 /* we call try-to-free pages for make this cgroup empty */
1517 lru_add_drain_all();
1518 /* try to free all pages in this cgroup */
1520 while (nr_retries
&& mem
->res
.usage
> 0) {
1523 if (signal_pending(current
)) {
1527 progress
= try_to_free_mem_cgroup_pages(mem
,
1528 GFP_HIGHUSER_MOVABLE
, false);
1531 /* maybe some writeback is necessary */
1532 congestion_wait(WRITE
, HZ
/10);
1537 /* try move_account...there may be some *locked* pages. */
1544 int mem_cgroup_force_empty_write(struct cgroup
*cont
, unsigned int event
)
1546 return mem_cgroup_force_empty(mem_cgroup_from_cont(cont
), true);
1550 static u64
mem_cgroup_hierarchy_read(struct cgroup
*cont
, struct cftype
*cft
)
1552 return mem_cgroup_from_cont(cont
)->use_hierarchy
;
1555 static int mem_cgroup_hierarchy_write(struct cgroup
*cont
, struct cftype
*cft
,
1559 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1560 struct cgroup
*parent
= cont
->parent
;
1561 struct mem_cgroup
*parent_mem
= NULL
;
1564 parent_mem
= mem_cgroup_from_cont(parent
);
1568 * If parent's use_hiearchy is set, we can't make any modifications
1569 * in the child subtrees. If it is unset, then the change can
1570 * occur, provided the current cgroup has no children.
1572 * For the root cgroup, parent_mem is NULL, we allow value to be
1573 * set if there are no children.
1575 if ((!parent_mem
|| !parent_mem
->use_hierarchy
) &&
1576 (val
== 1 || val
== 0)) {
1577 if (list_empty(&cont
->children
))
1578 mem
->use_hierarchy
= val
;
1588 static u64
mem_cgroup_read(struct cgroup
*cont
, struct cftype
*cft
)
1590 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1594 type
= MEMFILE_TYPE(cft
->private);
1595 name
= MEMFILE_ATTR(cft
->private);
1598 val
= res_counter_read_u64(&mem
->res
, name
);
1601 if (do_swap_account
)
1602 val
= res_counter_read_u64(&mem
->memsw
, name
);
1611 * The user of this function is...
1614 static int mem_cgroup_write(struct cgroup
*cont
, struct cftype
*cft
,
1617 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cont
);
1619 unsigned long long val
;
1622 type
= MEMFILE_TYPE(cft
->private);
1623 name
= MEMFILE_ATTR(cft
->private);
1626 /* This function does all necessary parse...reuse it */
1627 ret
= res_counter_memparse_write_strategy(buffer
, &val
);
1631 ret
= mem_cgroup_resize_limit(memcg
, val
);
1633 ret
= mem_cgroup_resize_memsw_limit(memcg
, val
);
1636 ret
= -EINVAL
; /* should be BUG() ? */
1642 static int mem_cgroup_reset(struct cgroup
*cont
, unsigned int event
)
1644 struct mem_cgroup
*mem
;
1647 mem
= mem_cgroup_from_cont(cont
);
1648 type
= MEMFILE_TYPE(event
);
1649 name
= MEMFILE_ATTR(event
);
1653 res_counter_reset_max(&mem
->res
);
1655 res_counter_reset_max(&mem
->memsw
);
1659 res_counter_reset_failcnt(&mem
->res
);
1661 res_counter_reset_failcnt(&mem
->memsw
);
1667 static const struct mem_cgroup_stat_desc
{
1670 } mem_cgroup_stat_desc
[] = {
1671 [MEM_CGROUP_STAT_CACHE
] = { "cache", PAGE_SIZE
, },
1672 [MEM_CGROUP_STAT_RSS
] = { "rss", PAGE_SIZE
, },
1673 [MEM_CGROUP_STAT_PGPGIN_COUNT
] = {"pgpgin", 1, },
1674 [MEM_CGROUP_STAT_PGPGOUT_COUNT
] = {"pgpgout", 1, },
1677 static int mem_control_stat_show(struct cgroup
*cont
, struct cftype
*cft
,
1678 struct cgroup_map_cb
*cb
)
1680 struct mem_cgroup
*mem_cont
= mem_cgroup_from_cont(cont
);
1681 struct mem_cgroup_stat
*stat
= &mem_cont
->stat
;
1684 for (i
= 0; i
< ARRAY_SIZE(stat
->cpustat
[0].count
); i
++) {
1687 val
= mem_cgroup_read_stat(stat
, i
);
1688 val
*= mem_cgroup_stat_desc
[i
].unit
;
1689 cb
->fill(cb
, mem_cgroup_stat_desc
[i
].msg
, val
);
1691 /* showing # of active pages */
1693 unsigned long active_anon
, inactive_anon
;
1694 unsigned long active_file
, inactive_file
;
1695 unsigned long unevictable
;
1697 inactive_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1699 active_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1701 inactive_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1703 active_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1705 unevictable
= mem_cgroup_get_all_zonestat(mem_cont
,
1708 cb
->fill(cb
, "active_anon", (active_anon
) * PAGE_SIZE
);
1709 cb
->fill(cb
, "inactive_anon", (inactive_anon
) * PAGE_SIZE
);
1710 cb
->fill(cb
, "active_file", (active_file
) * PAGE_SIZE
);
1711 cb
->fill(cb
, "inactive_file", (inactive_file
) * PAGE_SIZE
);
1712 cb
->fill(cb
, "unevictable", unevictable
* PAGE_SIZE
);
1719 static struct cftype mem_cgroup_files
[] = {
1721 .name
= "usage_in_bytes",
1722 .private = MEMFILE_PRIVATE(_MEM
, RES_USAGE
),
1723 .read_u64
= mem_cgroup_read
,
1726 .name
= "max_usage_in_bytes",
1727 .private = MEMFILE_PRIVATE(_MEM
, RES_MAX_USAGE
),
1728 .trigger
= mem_cgroup_reset
,
1729 .read_u64
= mem_cgroup_read
,
1732 .name
= "limit_in_bytes",
1733 .private = MEMFILE_PRIVATE(_MEM
, RES_LIMIT
),
1734 .write_string
= mem_cgroup_write
,
1735 .read_u64
= mem_cgroup_read
,
1739 .private = MEMFILE_PRIVATE(_MEM
, RES_FAILCNT
),
1740 .trigger
= mem_cgroup_reset
,
1741 .read_u64
= mem_cgroup_read
,
1745 .read_map
= mem_control_stat_show
,
1748 .name
= "force_empty",
1749 .trigger
= mem_cgroup_force_empty_write
,
1752 .name
= "use_hierarchy",
1753 .write_u64
= mem_cgroup_hierarchy_write
,
1754 .read_u64
= mem_cgroup_hierarchy_read
,
1758 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1759 static struct cftype memsw_cgroup_files
[] = {
1761 .name
= "memsw.usage_in_bytes",
1762 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_USAGE
),
1763 .read_u64
= mem_cgroup_read
,
1766 .name
= "memsw.max_usage_in_bytes",
1767 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_MAX_USAGE
),
1768 .trigger
= mem_cgroup_reset
,
1769 .read_u64
= mem_cgroup_read
,
1772 .name
= "memsw.limit_in_bytes",
1773 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_LIMIT
),
1774 .write_string
= mem_cgroup_write
,
1775 .read_u64
= mem_cgroup_read
,
1778 .name
= "memsw.failcnt",
1779 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_FAILCNT
),
1780 .trigger
= mem_cgroup_reset
,
1781 .read_u64
= mem_cgroup_read
,
1785 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1787 if (!do_swap_account
)
1789 return cgroup_add_files(cont
, ss
, memsw_cgroup_files
,
1790 ARRAY_SIZE(memsw_cgroup_files
));
1793 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1799 static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
1801 struct mem_cgroup_per_node
*pn
;
1802 struct mem_cgroup_per_zone
*mz
;
1804 int zone
, tmp
= node
;
1806 * This routine is called against possible nodes.
1807 * But it's BUG to call kmalloc() against offline node.
1809 * TODO: this routine can waste much memory for nodes which will
1810 * never be onlined. It's better to use memory hotplug callback
1813 if (!node_state(node
, N_NORMAL_MEMORY
))
1815 pn
= kmalloc_node(sizeof(*pn
), GFP_KERNEL
, tmp
);
1819 mem
->info
.nodeinfo
[node
] = pn
;
1820 memset(pn
, 0, sizeof(*pn
));
1822 for (zone
= 0; zone
< MAX_NR_ZONES
; zone
++) {
1823 mz
= &pn
->zoneinfo
[zone
];
1825 INIT_LIST_HEAD(&mz
->lists
[l
]);
1830 static void free_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
1832 kfree(mem
->info
.nodeinfo
[node
]);
1835 static int mem_cgroup_size(void)
1837 int cpustat_size
= nr_cpu_ids
* sizeof(struct mem_cgroup_stat_cpu
);
1838 return sizeof(struct mem_cgroup
) + cpustat_size
;
1841 static struct mem_cgroup
*mem_cgroup_alloc(void)
1843 struct mem_cgroup
*mem
;
1844 int size
= mem_cgroup_size();
1846 if (size
< PAGE_SIZE
)
1847 mem
= kmalloc(size
, GFP_KERNEL
);
1849 mem
= vmalloc(size
);
1852 memset(mem
, 0, size
);
1857 * At destroying mem_cgroup, references from swap_cgroup can remain.
1858 * (scanning all at force_empty is too costly...)
1860 * Instead of clearing all references at force_empty, we remember
1861 * the number of reference from swap_cgroup and free mem_cgroup when
1862 * it goes down to 0.
1864 * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and
1865 * entry which points to this memcg will be ignore at swapin.
1867 * Removal of cgroup itself succeeds regardless of refs from swap.
1870 static void mem_cgroup_free(struct mem_cgroup
*mem
)
1874 if (atomic_read(&mem
->refcnt
) > 0)
1878 for_each_node_state(node
, N_POSSIBLE
)
1879 free_mem_cgroup_per_zone_info(mem
, node
);
1881 if (mem_cgroup_size() < PAGE_SIZE
)
1887 static void mem_cgroup_get(struct mem_cgroup
*mem
)
1889 atomic_inc(&mem
->refcnt
);
1892 static void mem_cgroup_put(struct mem_cgroup
*mem
)
1894 if (atomic_dec_and_test(&mem
->refcnt
)) {
1897 mem_cgroup_free(mem
);
1902 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1903 static void __init
enable_swap_cgroup(void)
1905 if (!mem_cgroup_disabled() && really_do_swap_account
)
1906 do_swap_account
= 1;
1909 static void __init
enable_swap_cgroup(void)
1914 static struct cgroup_subsys_state
*
1915 mem_cgroup_create(struct cgroup_subsys
*ss
, struct cgroup
*cont
)
1917 struct mem_cgroup
*mem
, *parent
;
1920 mem
= mem_cgroup_alloc();
1922 return ERR_PTR(-ENOMEM
);
1924 for_each_node_state(node
, N_POSSIBLE
)
1925 if (alloc_mem_cgroup_per_zone_info(mem
, node
))
1928 if (cont
->parent
== NULL
) {
1929 enable_swap_cgroup();
1932 parent
= mem_cgroup_from_cont(cont
->parent
);
1933 mem
->use_hierarchy
= parent
->use_hierarchy
;
1936 if (parent
&& parent
->use_hierarchy
) {
1937 res_counter_init(&mem
->res
, &parent
->res
);
1938 res_counter_init(&mem
->memsw
, &parent
->memsw
);
1940 res_counter_init(&mem
->res
, NULL
);
1941 res_counter_init(&mem
->memsw
, NULL
);
1944 mem
->last_scanned_child
= NULL
;
1948 for_each_node_state(node
, N_POSSIBLE
)
1949 free_mem_cgroup_per_zone_info(mem
, node
);
1950 mem_cgroup_free(mem
);
1951 return ERR_PTR(-ENOMEM
);
1954 static void mem_cgroup_pre_destroy(struct cgroup_subsys
*ss
,
1955 struct cgroup
*cont
)
1957 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1959 mem_cgroup_force_empty(mem
, false);
1962 static void mem_cgroup_destroy(struct cgroup_subsys
*ss
,
1963 struct cgroup
*cont
)
1965 mem_cgroup_free(mem_cgroup_from_cont(cont
));
1968 static int mem_cgroup_populate(struct cgroup_subsys
*ss
,
1969 struct cgroup
*cont
)
1973 ret
= cgroup_add_files(cont
, ss
, mem_cgroup_files
,
1974 ARRAY_SIZE(mem_cgroup_files
));
1977 ret
= register_memsw_files(cont
, ss
);
1981 static void mem_cgroup_move_task(struct cgroup_subsys
*ss
,
1982 struct cgroup
*cont
,
1983 struct cgroup
*old_cont
,
1984 struct task_struct
*p
)
1986 struct mm_struct
*mm
;
1987 struct mem_cgroup
*mem
, *old_mem
;
1989 mm
= get_task_mm(p
);
1993 mem
= mem_cgroup_from_cont(cont
);
1994 old_mem
= mem_cgroup_from_cont(old_cont
);
1997 * Only thread group leaders are allowed to migrate, the mm_struct is
1998 * in effect owned by the leader
2000 if (!thread_group_leader(p
))
2007 struct cgroup_subsys mem_cgroup_subsys
= {
2009 .subsys_id
= mem_cgroup_subsys_id
,
2010 .create
= mem_cgroup_create
,
2011 .pre_destroy
= mem_cgroup_pre_destroy
,
2012 .destroy
= mem_cgroup_destroy
,
2013 .populate
= mem_cgroup_populate
,
2014 .attach
= mem_cgroup_move_task
,
2018 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2020 static int __init
disable_swap_account(char *s
)
2022 really_do_swap_account
= 0;
2025 __setup("noswapaccount", disable_swap_account
);