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 */
149 * statistics. This must be placed at the end of memcg.
151 struct mem_cgroup_stat stat
;
155 MEM_CGROUP_CHARGE_TYPE_CACHE
= 0,
156 MEM_CGROUP_CHARGE_TYPE_MAPPED
,
157 MEM_CGROUP_CHARGE_TYPE_SHMEM
, /* used by page migration of shmem */
158 MEM_CGROUP_CHARGE_TYPE_FORCE
, /* used by force_empty */
159 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
, /* for accounting swapcache */
163 /* only for here (for easy reading.) */
164 #define PCGF_CACHE (1UL << PCG_CACHE)
165 #define PCGF_USED (1UL << PCG_USED)
166 #define PCGF_LOCK (1UL << PCG_LOCK)
167 static const unsigned long
168 pcg_default_flags
[NR_CHARGE_TYPE
] = {
169 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* File Cache */
170 PCGF_USED
| PCGF_LOCK
, /* Anon */
171 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* Shmem */
176 /* for encoding cft->private value on file */
179 #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
180 #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
181 #define MEMFILE_ATTR(val) ((val) & 0xffff)
183 static void mem_cgroup_get(struct mem_cgroup
*mem
);
184 static void mem_cgroup_put(struct mem_cgroup
*mem
);
186 static void mem_cgroup_charge_statistics(struct mem_cgroup
*mem
,
187 struct page_cgroup
*pc
,
190 int val
= (charge
)? 1 : -1;
191 struct mem_cgroup_stat
*stat
= &mem
->stat
;
192 struct mem_cgroup_stat_cpu
*cpustat
;
195 cpustat
= &stat
->cpustat
[cpu
];
196 if (PageCgroupCache(pc
))
197 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_CACHE
, val
);
199 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_RSS
, val
);
202 __mem_cgroup_stat_add_safe(cpustat
,
203 MEM_CGROUP_STAT_PGPGIN_COUNT
, 1);
205 __mem_cgroup_stat_add_safe(cpustat
,
206 MEM_CGROUP_STAT_PGPGOUT_COUNT
, 1);
210 static struct mem_cgroup_per_zone
*
211 mem_cgroup_zoneinfo(struct mem_cgroup
*mem
, int nid
, int zid
)
213 return &mem
->info
.nodeinfo
[nid
]->zoneinfo
[zid
];
216 static struct mem_cgroup_per_zone
*
217 page_cgroup_zoneinfo(struct page_cgroup
*pc
)
219 struct mem_cgroup
*mem
= pc
->mem_cgroup
;
220 int nid
= page_cgroup_nid(pc
);
221 int zid
= page_cgroup_zid(pc
);
223 return mem_cgroup_zoneinfo(mem
, nid
, zid
);
226 static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup
*mem
,
230 struct mem_cgroup_per_zone
*mz
;
233 for_each_online_node(nid
)
234 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
235 mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
236 total
+= MEM_CGROUP_ZSTAT(mz
, idx
);
241 static struct mem_cgroup
*mem_cgroup_from_cont(struct cgroup
*cont
)
243 return container_of(cgroup_subsys_state(cont
,
244 mem_cgroup_subsys_id
), struct mem_cgroup
,
248 struct mem_cgroup
*mem_cgroup_from_task(struct task_struct
*p
)
251 * mm_update_next_owner() may clear mm->owner to NULL
252 * if it races with swapoff, page migration, etc.
253 * So this can be called with p == NULL.
258 return container_of(task_subsys_state(p
, mem_cgroup_subsys_id
),
259 struct mem_cgroup
, css
);
263 * Following LRU functions are allowed to be used without PCG_LOCK.
264 * Operations are called by routine of global LRU independently from memcg.
265 * What we have to take care of here is validness of pc->mem_cgroup.
267 * Changes to pc->mem_cgroup happens when
270 * In typical case, "charge" is done before add-to-lru. Exception is SwapCache.
271 * It is added to LRU before charge.
272 * If PCG_USED bit is not set, page_cgroup is not added to this private LRU.
273 * When moving account, the page is not on LRU. It's isolated.
276 void mem_cgroup_del_lru_list(struct page
*page
, enum lru_list lru
)
278 struct page_cgroup
*pc
;
279 struct mem_cgroup
*mem
;
280 struct mem_cgroup_per_zone
*mz
;
282 if (mem_cgroup_disabled())
284 pc
= lookup_page_cgroup(page
);
285 /* can happen while we handle swapcache. */
286 if (list_empty(&pc
->lru
))
288 mz
= page_cgroup_zoneinfo(pc
);
289 mem
= pc
->mem_cgroup
;
290 MEM_CGROUP_ZSTAT(mz
, lru
) -= 1;
291 list_del_init(&pc
->lru
);
295 void mem_cgroup_del_lru(struct page
*page
)
297 mem_cgroup_del_lru_list(page
, page_lru(page
));
300 void mem_cgroup_rotate_lru_list(struct page
*page
, enum lru_list lru
)
302 struct mem_cgroup_per_zone
*mz
;
303 struct page_cgroup
*pc
;
305 if (mem_cgroup_disabled())
308 pc
= lookup_page_cgroup(page
);
310 /* unused page is not rotated. */
311 if (!PageCgroupUsed(pc
))
313 mz
= page_cgroup_zoneinfo(pc
);
314 list_move(&pc
->lru
, &mz
->lists
[lru
]);
317 void mem_cgroup_add_lru_list(struct page
*page
, enum lru_list lru
)
319 struct page_cgroup
*pc
;
320 struct mem_cgroup_per_zone
*mz
;
322 if (mem_cgroup_disabled())
324 pc
= lookup_page_cgroup(page
);
325 /* barrier to sync with "charge" */
327 if (!PageCgroupUsed(pc
))
330 mz
= page_cgroup_zoneinfo(pc
);
331 MEM_CGROUP_ZSTAT(mz
, lru
) += 1;
332 list_add(&pc
->lru
, &mz
->lists
[lru
]);
335 * To add swapcache into LRU. Be careful to all this function.
336 * zone->lru_lock shouldn't be held and irq must not be disabled.
338 static void mem_cgroup_lru_fixup(struct page
*page
)
340 if (!isolate_lru_page(page
))
341 putback_lru_page(page
);
344 void mem_cgroup_move_lists(struct page
*page
,
345 enum lru_list from
, enum lru_list to
)
347 if (mem_cgroup_disabled())
349 mem_cgroup_del_lru_list(page
, from
);
350 mem_cgroup_add_lru_list(page
, to
);
353 int task_in_mem_cgroup(struct task_struct
*task
, const struct mem_cgroup
*mem
)
358 ret
= task
->mm
&& mm_match_cgroup(task
->mm
, mem
);
364 * Calculate mapped_ratio under memory controller. This will be used in
365 * vmscan.c for deteremining we have to reclaim mapped pages.
367 int mem_cgroup_calc_mapped_ratio(struct mem_cgroup
*mem
)
372 * usage is recorded in bytes. But, here, we assume the number of
373 * physical pages can be represented by "long" on any arch.
375 total
= (long) (mem
->res
.usage
>> PAGE_SHIFT
) + 1L;
376 rss
= (long)mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_RSS
);
377 return (int)((rss
* 100L) / total
);
381 * prev_priority control...this will be used in memory reclaim path.
383 int mem_cgroup_get_reclaim_priority(struct mem_cgroup
*mem
)
385 return mem
->prev_priority
;
388 void mem_cgroup_note_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
390 if (priority
< mem
->prev_priority
)
391 mem
->prev_priority
= priority
;
394 void mem_cgroup_record_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
396 mem
->prev_priority
= priority
;
400 * Calculate # of pages to be scanned in this priority/zone.
403 * priority starts from "DEF_PRIORITY" and decremented in each loop.
404 * (see include/linux/mmzone.h)
407 long mem_cgroup_calc_reclaim(struct mem_cgroup
*mem
, struct zone
*zone
,
408 int priority
, enum lru_list lru
)
411 int nid
= zone
->zone_pgdat
->node_id
;
412 int zid
= zone_idx(zone
);
413 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
415 nr_pages
= MEM_CGROUP_ZSTAT(mz
, lru
);
417 return (nr_pages
>> priority
);
420 unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan
,
421 struct list_head
*dst
,
422 unsigned long *scanned
, int order
,
423 int mode
, struct zone
*z
,
424 struct mem_cgroup
*mem_cont
,
425 int active
, int file
)
427 unsigned long nr_taken
= 0;
431 struct list_head
*src
;
432 struct page_cgroup
*pc
, *tmp
;
433 int nid
= z
->zone_pgdat
->node_id
;
434 int zid
= zone_idx(z
);
435 struct mem_cgroup_per_zone
*mz
;
436 int lru
= LRU_FILE
* !!file
+ !!active
;
439 mz
= mem_cgroup_zoneinfo(mem_cont
, nid
, zid
);
440 src
= &mz
->lists
[lru
];
443 list_for_each_entry_safe_reverse(pc
, tmp
, src
, lru
) {
444 if (scan
>= nr_to_scan
)
448 if (unlikely(!PageCgroupUsed(pc
)))
450 if (unlikely(!PageLRU(page
)))
454 if (__isolate_lru_page(page
, mode
, file
) == 0) {
455 list_move(&page
->lru
, dst
);
465 * Unlike exported interface, "oom" parameter is added. if oom==true,
466 * oom-killer can be invoked.
468 static int __mem_cgroup_try_charge(struct mm_struct
*mm
,
469 gfp_t gfp_mask
, struct mem_cgroup
**memcg
,
472 struct mem_cgroup
*mem
;
473 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
475 * We always charge the cgroup the mm_struct belongs to.
476 * The mm_struct's mem_cgroup changes on task migration if the
477 * thread group leader migrates. It's possible that mm is not
478 * set, if so charge the init_mm (happens for pagecache usage).
480 if (likely(!*memcg
)) {
482 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
483 if (unlikely(!mem
)) {
488 * For every charge from the cgroup, increment reference count
502 ret
= res_counter_charge(&mem
->res
, PAGE_SIZE
);
504 if (!do_swap_account
)
506 ret
= res_counter_charge(&mem
->memsw
, PAGE_SIZE
);
509 /* mem+swap counter fails */
510 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
513 if (!(gfp_mask
& __GFP_WAIT
))
516 if (try_to_free_mem_cgroup_pages(mem
, gfp_mask
, noswap
))
520 * try_to_free_mem_cgroup_pages() might not give us a full
521 * picture of reclaim. Some pages are reclaimed and might be
522 * moved to swap cache or just unmapped from the cgroup.
523 * Check the limit again to see if the reclaim reduced the
524 * current usage of the cgroup before giving up
527 if (!do_swap_account
&&
528 res_counter_check_under_limit(&mem
->res
))
530 if (do_swap_account
&&
531 res_counter_check_under_limit(&mem
->memsw
))
536 mem_cgroup_out_of_memory(mem
, gfp_mask
);
547 * mem_cgroup_try_charge - get charge of PAGE_SIZE.
548 * @mm: an mm_struct which is charged against. (when *memcg is NULL)
549 * @gfp_mask: gfp_mask for reclaim.
550 * @memcg: a pointer to memory cgroup which is charged against.
552 * charge against memory cgroup pointed by *memcg. if *memcg == NULL, estimated
553 * memory cgroup from @mm is got and stored in *memcg.
555 * Returns 0 if success. -ENOMEM at failure.
556 * This call can invoke OOM-Killer.
559 int mem_cgroup_try_charge(struct mm_struct
*mm
,
560 gfp_t mask
, struct mem_cgroup
**memcg
)
562 return __mem_cgroup_try_charge(mm
, mask
, memcg
, true);
566 * commit a charge got by mem_cgroup_try_charge() and makes page_cgroup to be
567 * USED state. If already USED, uncharge and return.
570 static void __mem_cgroup_commit_charge(struct mem_cgroup
*mem
,
571 struct page_cgroup
*pc
,
572 enum charge_type ctype
)
574 /* try_charge() can return NULL to *memcg, taking care of it. */
578 lock_page_cgroup(pc
);
579 if (unlikely(PageCgroupUsed(pc
))) {
580 unlock_page_cgroup(pc
);
581 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
583 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
587 pc
->mem_cgroup
= mem
;
589 pc
->flags
= pcg_default_flags
[ctype
];
591 mem_cgroup_charge_statistics(mem
, pc
, true);
593 unlock_page_cgroup(pc
);
597 * mem_cgroup_move_account - move account of the page
598 * @pc: page_cgroup of the page.
599 * @from: mem_cgroup which the page is moved from.
600 * @to: mem_cgroup which the page is moved to. @from != @to.
602 * The caller must confirm following.
603 * - page is not on LRU (isolate_page() is useful.)
605 * returns 0 at success,
606 * returns -EBUSY when lock is busy or "pc" is unstable.
608 * This function does "uncharge" from old cgroup but doesn't do "charge" to
609 * new cgroup. It should be done by a caller.
612 static int mem_cgroup_move_account(struct page_cgroup
*pc
,
613 struct mem_cgroup
*from
, struct mem_cgroup
*to
)
615 struct mem_cgroup_per_zone
*from_mz
, *to_mz
;
619 VM_BUG_ON(from
== to
);
620 VM_BUG_ON(PageLRU(pc
->page
));
622 nid
= page_cgroup_nid(pc
);
623 zid
= page_cgroup_zid(pc
);
624 from_mz
= mem_cgroup_zoneinfo(from
, nid
, zid
);
625 to_mz
= mem_cgroup_zoneinfo(to
, nid
, zid
);
627 if (!trylock_page_cgroup(pc
))
630 if (!PageCgroupUsed(pc
))
633 if (pc
->mem_cgroup
!= from
)
637 res_counter_uncharge(&from
->res
, PAGE_SIZE
);
638 mem_cgroup_charge_statistics(from
, pc
, false);
640 res_counter_uncharge(&from
->memsw
, PAGE_SIZE
);
642 mem_cgroup_charge_statistics(to
, pc
, true);
646 unlock_page_cgroup(pc
);
651 * move charges to its parent.
654 static int mem_cgroup_move_parent(struct page_cgroup
*pc
,
655 struct mem_cgroup
*child
,
658 struct page
*page
= pc
->page
;
659 struct cgroup
*cg
= child
->css
.cgroup
;
660 struct cgroup
*pcg
= cg
->parent
;
661 struct mem_cgroup
*parent
;
669 parent
= mem_cgroup_from_cont(pcg
);
672 ret
= __mem_cgroup_try_charge(NULL
, gfp_mask
, &parent
, false);
676 if (!get_page_unless_zero(page
))
679 ret
= isolate_lru_page(page
);
684 ret
= mem_cgroup_move_account(pc
, child
, parent
);
686 /* drop extra refcnt by try_charge() (move_account increment one) */
687 css_put(&parent
->css
);
688 putback_lru_page(page
);
693 /* uncharge if move fails */
695 res_counter_uncharge(&parent
->res
, PAGE_SIZE
);
697 res_counter_uncharge(&parent
->memsw
, PAGE_SIZE
);
703 * Charge the memory controller for page usage.
705 * 0 if the charge was successful
706 * < 0 if the cgroup is over its limit
708 static int mem_cgroup_charge_common(struct page
*page
, struct mm_struct
*mm
,
709 gfp_t gfp_mask
, enum charge_type ctype
,
710 struct mem_cgroup
*memcg
)
712 struct mem_cgroup
*mem
;
713 struct page_cgroup
*pc
;
716 pc
= lookup_page_cgroup(page
);
717 /* can happen at boot */
723 ret
= __mem_cgroup_try_charge(mm
, gfp_mask
, &mem
, true);
727 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
731 int mem_cgroup_newpage_charge(struct page
*page
,
732 struct mm_struct
*mm
, gfp_t gfp_mask
)
734 if (mem_cgroup_disabled())
736 if (PageCompound(page
))
739 * If already mapped, we don't have to account.
740 * If page cache, page->mapping has address_space.
741 * But page->mapping may have out-of-use anon_vma pointer,
742 * detecit it by PageAnon() check. newly-mapped-anon's page->mapping
745 if (page_mapped(page
) || (page
->mapping
&& !PageAnon(page
)))
749 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
750 MEM_CGROUP_CHARGE_TYPE_MAPPED
, NULL
);
753 int mem_cgroup_cache_charge(struct page
*page
, struct mm_struct
*mm
,
756 if (mem_cgroup_disabled())
758 if (PageCompound(page
))
761 * Corner case handling. This is called from add_to_page_cache()
762 * in usual. But some FS (shmem) precharges this page before calling it
763 * and call add_to_page_cache() with GFP_NOWAIT.
765 * For GFP_NOWAIT case, the page may be pre-charged before calling
766 * add_to_page_cache(). (See shmem.c) check it here and avoid to call
767 * charge twice. (It works but has to pay a bit larger cost.)
769 if (!(gfp_mask
& __GFP_WAIT
)) {
770 struct page_cgroup
*pc
;
773 pc
= lookup_page_cgroup(page
);
776 lock_page_cgroup(pc
);
777 if (PageCgroupUsed(pc
)) {
778 unlock_page_cgroup(pc
);
781 unlock_page_cgroup(pc
);
787 if (page_is_file_cache(page
))
788 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
789 MEM_CGROUP_CHARGE_TYPE_CACHE
, NULL
);
791 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
792 MEM_CGROUP_CHARGE_TYPE_SHMEM
, NULL
);
795 int mem_cgroup_try_charge_swapin(struct mm_struct
*mm
,
797 gfp_t mask
, struct mem_cgroup
**ptr
)
799 struct mem_cgroup
*mem
;
802 if (mem_cgroup_disabled())
805 if (!do_swap_account
)
809 * A racing thread's fault, or swapoff, may have already updated
810 * the pte, and even removed page from swap cache: return success
811 * to go on to do_swap_page()'s pte_same() test, which should fail.
813 if (!PageSwapCache(page
))
816 ent
.val
= page_private(page
);
818 mem
= lookup_swap_cgroup(ent
);
819 if (!mem
|| mem
->obsolete
)
822 return __mem_cgroup_try_charge(NULL
, mask
, ptr
, true);
826 return __mem_cgroup_try_charge(mm
, mask
, ptr
, true);
831 int mem_cgroup_cache_charge_swapin(struct page
*page
,
832 struct mm_struct
*mm
, gfp_t mask
, bool locked
)
836 if (mem_cgroup_disabled())
843 * If not locked, the page can be dropped from SwapCache until
846 if (PageSwapCache(page
)) {
847 struct mem_cgroup
*mem
= NULL
;
850 ent
.val
= page_private(page
);
851 if (do_swap_account
) {
852 mem
= lookup_swap_cgroup(ent
);
853 if (mem
&& mem
->obsolete
)
858 ret
= mem_cgroup_charge_common(page
, mm
, mask
,
859 MEM_CGROUP_CHARGE_TYPE_SHMEM
, mem
);
861 if (!ret
&& do_swap_account
) {
862 /* avoid double counting */
863 mem
= swap_cgroup_record(ent
, NULL
);
865 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
872 /* add this page(page_cgroup) to the LRU we want. */
873 mem_cgroup_lru_fixup(page
);
879 void mem_cgroup_commit_charge_swapin(struct page
*page
, struct mem_cgroup
*ptr
)
881 struct page_cgroup
*pc
;
883 if (mem_cgroup_disabled())
887 pc
= lookup_page_cgroup(page
);
888 __mem_cgroup_commit_charge(ptr
, pc
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
890 * Now swap is on-memory. This means this page may be
891 * counted both as mem and swap....double count.
892 * Fix it by uncharging from memsw. This SwapCache is stable
893 * because we're still under lock_page().
895 if (do_swap_account
) {
896 swp_entry_t ent
= {.val
= page_private(page
)};
897 struct mem_cgroup
*memcg
;
898 memcg
= swap_cgroup_record(ent
, NULL
);
900 /* If memcg is obsolete, memcg can be != ptr */
901 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
902 mem_cgroup_put(memcg
);
906 /* add this page(page_cgroup) to the LRU we want. */
907 mem_cgroup_lru_fixup(page
);
910 void mem_cgroup_cancel_charge_swapin(struct mem_cgroup
*mem
)
912 if (mem_cgroup_disabled())
916 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
918 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
924 * uncharge if !page_mapped(page)
926 static struct mem_cgroup
*
927 __mem_cgroup_uncharge_common(struct page
*page
, enum charge_type ctype
)
929 struct page_cgroup
*pc
;
930 struct mem_cgroup
*mem
= NULL
;
931 struct mem_cgroup_per_zone
*mz
;
933 if (mem_cgroup_disabled())
936 if (PageSwapCache(page
))
940 * Check if our page_cgroup is valid
942 pc
= lookup_page_cgroup(page
);
943 if (unlikely(!pc
|| !PageCgroupUsed(pc
)))
946 lock_page_cgroup(pc
);
948 mem
= pc
->mem_cgroup
;
950 if (!PageCgroupUsed(pc
))
954 case MEM_CGROUP_CHARGE_TYPE_MAPPED
:
955 if (page_mapped(page
))
958 case MEM_CGROUP_CHARGE_TYPE_SWAPOUT
:
959 if (!PageAnon(page
)) { /* Shared memory */
960 if (page
->mapping
&& !page_is_file_cache(page
))
962 } else if (page_mapped(page
)) /* Anon */
969 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
970 if (do_swap_account
&& (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
))
971 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
973 mem_cgroup_charge_statistics(mem
, pc
, false);
974 ClearPageCgroupUsed(pc
);
976 mz
= page_cgroup_zoneinfo(pc
);
977 unlock_page_cgroup(pc
);
984 unlock_page_cgroup(pc
);
988 void mem_cgroup_uncharge_page(struct page
*page
)
991 if (page_mapped(page
))
993 if (page
->mapping
&& !PageAnon(page
))
995 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
998 void mem_cgroup_uncharge_cache_page(struct page
*page
)
1000 VM_BUG_ON(page_mapped(page
));
1001 VM_BUG_ON(page
->mapping
);
1002 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_CACHE
);
1006 * called from __delete_from_swap_cache() and drop "page" account.
1007 * memcg information is recorded to swap_cgroup of "ent"
1009 void mem_cgroup_uncharge_swapcache(struct page
*page
, swp_entry_t ent
)
1011 struct mem_cgroup
*memcg
;
1013 memcg
= __mem_cgroup_uncharge_common(page
,
1014 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
);
1015 /* record memcg information */
1016 if (do_swap_account
&& memcg
) {
1017 swap_cgroup_record(ent
, memcg
);
1018 mem_cgroup_get(memcg
);
1022 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1024 * called from swap_entry_free(). remove record in swap_cgroup and
1025 * uncharge "memsw" account.
1027 void mem_cgroup_uncharge_swap(swp_entry_t ent
)
1029 struct mem_cgroup
*memcg
;
1031 if (!do_swap_account
)
1034 memcg
= swap_cgroup_record(ent
, NULL
);
1036 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1037 mem_cgroup_put(memcg
);
1043 * Before starting migration, account PAGE_SIZE to mem_cgroup that the old
1046 int mem_cgroup_prepare_migration(struct page
*page
, struct mem_cgroup
**ptr
)
1048 struct page_cgroup
*pc
;
1049 struct mem_cgroup
*mem
= NULL
;
1052 if (mem_cgroup_disabled())
1055 pc
= lookup_page_cgroup(page
);
1056 lock_page_cgroup(pc
);
1057 if (PageCgroupUsed(pc
)) {
1058 mem
= pc
->mem_cgroup
;
1061 unlock_page_cgroup(pc
);
1064 ret
= mem_cgroup_try_charge(NULL
, GFP_HIGHUSER_MOVABLE
, &mem
);
1071 /* remove redundant charge if migration failed*/
1072 void mem_cgroup_end_migration(struct mem_cgroup
*mem
,
1073 struct page
*oldpage
, struct page
*newpage
)
1075 struct page
*target
, *unused
;
1076 struct page_cgroup
*pc
;
1077 enum charge_type ctype
;
1082 /* at migration success, oldpage->mapping is NULL. */
1083 if (oldpage
->mapping
) {
1091 if (PageAnon(target
))
1092 ctype
= MEM_CGROUP_CHARGE_TYPE_MAPPED
;
1093 else if (page_is_file_cache(target
))
1094 ctype
= MEM_CGROUP_CHARGE_TYPE_CACHE
;
1096 ctype
= MEM_CGROUP_CHARGE_TYPE_SHMEM
;
1098 /* unused page is not on radix-tree now. */
1100 __mem_cgroup_uncharge_common(unused
, ctype
);
1102 pc
= lookup_page_cgroup(target
);
1104 * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
1105 * So, double-counting is effectively avoided.
1107 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
1110 * Both of oldpage and newpage are still under lock_page().
1111 * Then, we don't have to care about race in radix-tree.
1112 * But we have to be careful that this page is unmapped or not.
1114 * There is a case for !page_mapped(). At the start of
1115 * migration, oldpage was mapped. But now, it's zapped.
1116 * But we know *target* page is not freed/reused under us.
1117 * mem_cgroup_uncharge_page() does all necessary checks.
1119 if (ctype
== MEM_CGROUP_CHARGE_TYPE_MAPPED
)
1120 mem_cgroup_uncharge_page(target
);
1124 * A call to try to shrink memory usage under specified resource controller.
1125 * This is typically used for page reclaiming for shmem for reducing side
1126 * effect of page allocation from shmem, which is used by some mem_cgroup.
1128 int mem_cgroup_shrink_usage(struct mm_struct
*mm
, gfp_t gfp_mask
)
1130 struct mem_cgroup
*mem
;
1132 int retry
= MEM_CGROUP_RECLAIM_RETRIES
;
1134 if (mem_cgroup_disabled())
1140 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
1141 if (unlikely(!mem
)) {
1149 progress
= try_to_free_mem_cgroup_pages(mem
, gfp_mask
, true);
1150 progress
+= res_counter_check_under_limit(&mem
->res
);
1151 } while (!progress
&& --retry
);
1159 static DEFINE_MUTEX(set_limit_mutex
);
1161 static int mem_cgroup_resize_limit(struct mem_cgroup
*memcg
,
1162 unsigned long long val
)
1165 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1170 while (retry_count
) {
1171 if (signal_pending(current
)) {
1176 * Rather than hide all in some function, I do this in
1177 * open coded manner. You see what this really does.
1178 * We have to guarantee mem->res.limit < mem->memsw.limit.
1180 mutex_lock(&set_limit_mutex
);
1181 memswlimit
= res_counter_read_u64(&memcg
->memsw
, RES_LIMIT
);
1182 if (memswlimit
< val
) {
1184 mutex_unlock(&set_limit_mutex
);
1187 ret
= res_counter_set_limit(&memcg
->res
, val
);
1188 mutex_unlock(&set_limit_mutex
);
1193 progress
= try_to_free_mem_cgroup_pages(memcg
,
1194 GFP_HIGHUSER_MOVABLE
, false);
1195 if (!progress
) retry_count
--;
1200 int mem_cgroup_resize_memsw_limit(struct mem_cgroup
*memcg
,
1201 unsigned long long val
)
1203 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1204 u64 memlimit
, oldusage
, curusage
;
1207 if (!do_swap_account
)
1210 while (retry_count
) {
1211 if (signal_pending(current
)) {
1216 * Rather than hide all in some function, I do this in
1217 * open coded manner. You see what this really does.
1218 * We have to guarantee mem->res.limit < mem->memsw.limit.
1220 mutex_lock(&set_limit_mutex
);
1221 memlimit
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
);
1222 if (memlimit
> val
) {
1224 mutex_unlock(&set_limit_mutex
);
1227 ret
= res_counter_set_limit(&memcg
->memsw
, val
);
1228 mutex_unlock(&set_limit_mutex
);
1233 oldusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1234 try_to_free_mem_cgroup_pages(memcg
, GFP_HIGHUSER_MOVABLE
, true);
1235 curusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1236 if (curusage
>= oldusage
)
1243 * This routine traverse page_cgroup in given list and drop them all.
1244 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
1246 static int mem_cgroup_force_empty_list(struct mem_cgroup
*mem
,
1247 int node
, int zid
, enum lru_list lru
)
1250 struct mem_cgroup_per_zone
*mz
;
1251 struct page_cgroup
*pc
, *busy
;
1252 unsigned long flags
, loop
;
1253 struct list_head
*list
;
1256 zone
= &NODE_DATA(node
)->node_zones
[zid
];
1257 mz
= mem_cgroup_zoneinfo(mem
, node
, zid
);
1258 list
= &mz
->lists
[lru
];
1260 loop
= MEM_CGROUP_ZSTAT(mz
, lru
);
1261 /* give some margin against EBUSY etc...*/
1266 spin_lock_irqsave(&zone
->lru_lock
, flags
);
1267 if (list_empty(list
)) {
1268 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1271 pc
= list_entry(list
->prev
, struct page_cgroup
, lru
);
1273 list_move(&pc
->lru
, list
);
1275 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1278 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1280 ret
= mem_cgroup_move_parent(pc
, mem
, GFP_HIGHUSER_MOVABLE
);
1284 if (ret
== -EBUSY
|| ret
== -EINVAL
) {
1285 /* found lock contention or "pc" is obsolete. */
1292 if (!ret
&& !list_empty(list
))
1298 * make mem_cgroup's charge to be 0 if there is no task.
1299 * This enables deleting this mem_cgroup.
1301 static int mem_cgroup_force_empty(struct mem_cgroup
*mem
, bool free_all
)
1304 int node
, zid
, shrink
;
1305 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
1306 struct cgroup
*cgrp
= mem
->css
.cgroup
;
1311 /* should free all ? */
1315 while (mem
->res
.usage
> 0) {
1317 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
))
1320 if (signal_pending(current
))
1322 /* This is for making all *used* pages to be on LRU. */
1323 lru_add_drain_all();
1325 for_each_node_state(node
, N_POSSIBLE
) {
1326 for (zid
= 0; !ret
&& zid
< MAX_NR_ZONES
; zid
++) {
1329 ret
= mem_cgroup_force_empty_list(mem
,
1338 /* it seems parent cgroup doesn't have enough mem */
1349 /* returns EBUSY if there is a task or if we come here twice. */
1350 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
) || shrink
) {
1354 /* we call try-to-free pages for make this cgroup empty */
1355 lru_add_drain_all();
1356 /* try to free all pages in this cgroup */
1358 while (nr_retries
&& mem
->res
.usage
> 0) {
1361 if (signal_pending(current
)) {
1365 progress
= try_to_free_mem_cgroup_pages(mem
,
1366 GFP_HIGHUSER_MOVABLE
, false);
1369 /* maybe some writeback is necessary */
1370 congestion_wait(WRITE
, HZ
/10);
1375 /* try move_account...there may be some *locked* pages. */
1382 int mem_cgroup_force_empty_write(struct cgroup
*cont
, unsigned int event
)
1384 return mem_cgroup_force_empty(mem_cgroup_from_cont(cont
), true);
1388 static u64
mem_cgroup_read(struct cgroup
*cont
, struct cftype
*cft
)
1390 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1394 type
= MEMFILE_TYPE(cft
->private);
1395 name
= MEMFILE_ATTR(cft
->private);
1398 val
= res_counter_read_u64(&mem
->res
, name
);
1401 if (do_swap_account
)
1402 val
= res_counter_read_u64(&mem
->memsw
, name
);
1411 * The user of this function is...
1414 static int mem_cgroup_write(struct cgroup
*cont
, struct cftype
*cft
,
1417 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cont
);
1419 unsigned long long val
;
1422 type
= MEMFILE_TYPE(cft
->private);
1423 name
= MEMFILE_ATTR(cft
->private);
1426 /* This function does all necessary parse...reuse it */
1427 ret
= res_counter_memparse_write_strategy(buffer
, &val
);
1431 ret
= mem_cgroup_resize_limit(memcg
, val
);
1433 ret
= mem_cgroup_resize_memsw_limit(memcg
, val
);
1436 ret
= -EINVAL
; /* should be BUG() ? */
1442 static int mem_cgroup_reset(struct cgroup
*cont
, unsigned int event
)
1444 struct mem_cgroup
*mem
;
1447 mem
= mem_cgroup_from_cont(cont
);
1448 type
= MEMFILE_TYPE(event
);
1449 name
= MEMFILE_ATTR(event
);
1453 res_counter_reset_max(&mem
->res
);
1455 res_counter_reset_max(&mem
->memsw
);
1459 res_counter_reset_failcnt(&mem
->res
);
1461 res_counter_reset_failcnt(&mem
->memsw
);
1467 static const struct mem_cgroup_stat_desc
{
1470 } mem_cgroup_stat_desc
[] = {
1471 [MEM_CGROUP_STAT_CACHE
] = { "cache", PAGE_SIZE
, },
1472 [MEM_CGROUP_STAT_RSS
] = { "rss", PAGE_SIZE
, },
1473 [MEM_CGROUP_STAT_PGPGIN_COUNT
] = {"pgpgin", 1, },
1474 [MEM_CGROUP_STAT_PGPGOUT_COUNT
] = {"pgpgout", 1, },
1477 static int mem_control_stat_show(struct cgroup
*cont
, struct cftype
*cft
,
1478 struct cgroup_map_cb
*cb
)
1480 struct mem_cgroup
*mem_cont
= mem_cgroup_from_cont(cont
);
1481 struct mem_cgroup_stat
*stat
= &mem_cont
->stat
;
1484 for (i
= 0; i
< ARRAY_SIZE(stat
->cpustat
[0].count
); i
++) {
1487 val
= mem_cgroup_read_stat(stat
, i
);
1488 val
*= mem_cgroup_stat_desc
[i
].unit
;
1489 cb
->fill(cb
, mem_cgroup_stat_desc
[i
].msg
, val
);
1491 /* showing # of active pages */
1493 unsigned long active_anon
, inactive_anon
;
1494 unsigned long active_file
, inactive_file
;
1495 unsigned long unevictable
;
1497 inactive_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1499 active_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1501 inactive_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1503 active_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1505 unevictable
= mem_cgroup_get_all_zonestat(mem_cont
,
1508 cb
->fill(cb
, "active_anon", (active_anon
) * PAGE_SIZE
);
1509 cb
->fill(cb
, "inactive_anon", (inactive_anon
) * PAGE_SIZE
);
1510 cb
->fill(cb
, "active_file", (active_file
) * PAGE_SIZE
);
1511 cb
->fill(cb
, "inactive_file", (inactive_file
) * PAGE_SIZE
);
1512 cb
->fill(cb
, "unevictable", unevictable
* PAGE_SIZE
);
1519 static struct cftype mem_cgroup_files
[] = {
1521 .name
= "usage_in_bytes",
1522 .private = MEMFILE_PRIVATE(_MEM
, RES_USAGE
),
1523 .read_u64
= mem_cgroup_read
,
1526 .name
= "max_usage_in_bytes",
1527 .private = MEMFILE_PRIVATE(_MEM
, RES_MAX_USAGE
),
1528 .trigger
= mem_cgroup_reset
,
1529 .read_u64
= mem_cgroup_read
,
1532 .name
= "limit_in_bytes",
1533 .private = MEMFILE_PRIVATE(_MEM
, RES_LIMIT
),
1534 .write_string
= mem_cgroup_write
,
1535 .read_u64
= mem_cgroup_read
,
1539 .private = MEMFILE_PRIVATE(_MEM
, RES_FAILCNT
),
1540 .trigger
= mem_cgroup_reset
,
1541 .read_u64
= mem_cgroup_read
,
1545 .read_map
= mem_control_stat_show
,
1548 .name
= "force_empty",
1549 .trigger
= mem_cgroup_force_empty_write
,
1553 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1554 static struct cftype memsw_cgroup_files
[] = {
1556 .name
= "memsw.usage_in_bytes",
1557 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_USAGE
),
1558 .read_u64
= mem_cgroup_read
,
1561 .name
= "memsw.max_usage_in_bytes",
1562 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_MAX_USAGE
),
1563 .trigger
= mem_cgroup_reset
,
1564 .read_u64
= mem_cgroup_read
,
1567 .name
= "memsw.limit_in_bytes",
1568 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_LIMIT
),
1569 .write_string
= mem_cgroup_write
,
1570 .read_u64
= mem_cgroup_read
,
1573 .name
= "memsw.failcnt",
1574 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_FAILCNT
),
1575 .trigger
= mem_cgroup_reset
,
1576 .read_u64
= mem_cgroup_read
,
1580 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1582 if (!do_swap_account
)
1584 return cgroup_add_files(cont
, ss
, memsw_cgroup_files
,
1585 ARRAY_SIZE(memsw_cgroup_files
));
1588 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1594 static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
1596 struct mem_cgroup_per_node
*pn
;
1597 struct mem_cgroup_per_zone
*mz
;
1599 int zone
, tmp
= node
;
1601 * This routine is called against possible nodes.
1602 * But it's BUG to call kmalloc() against offline node.
1604 * TODO: this routine can waste much memory for nodes which will
1605 * never be onlined. It's better to use memory hotplug callback
1608 if (!node_state(node
, N_NORMAL_MEMORY
))
1610 pn
= kmalloc_node(sizeof(*pn
), GFP_KERNEL
, tmp
);
1614 mem
->info
.nodeinfo
[node
] = pn
;
1615 memset(pn
, 0, sizeof(*pn
));
1617 for (zone
= 0; zone
< MAX_NR_ZONES
; zone
++) {
1618 mz
= &pn
->zoneinfo
[zone
];
1620 INIT_LIST_HEAD(&mz
->lists
[l
]);
1625 static void free_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
1627 kfree(mem
->info
.nodeinfo
[node
]);
1630 static int mem_cgroup_size(void)
1632 int cpustat_size
= nr_cpu_ids
* sizeof(struct mem_cgroup_stat_cpu
);
1633 return sizeof(struct mem_cgroup
) + cpustat_size
;
1636 static struct mem_cgroup
*mem_cgroup_alloc(void)
1638 struct mem_cgroup
*mem
;
1639 int size
= mem_cgroup_size();
1641 if (size
< PAGE_SIZE
)
1642 mem
= kmalloc(size
, GFP_KERNEL
);
1644 mem
= vmalloc(size
);
1647 memset(mem
, 0, size
);
1652 * At destroying mem_cgroup, references from swap_cgroup can remain.
1653 * (scanning all at force_empty is too costly...)
1655 * Instead of clearing all references at force_empty, we remember
1656 * the number of reference from swap_cgroup and free mem_cgroup when
1657 * it goes down to 0.
1659 * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and
1660 * entry which points to this memcg will be ignore at swapin.
1662 * Removal of cgroup itself succeeds regardless of refs from swap.
1665 static void mem_cgroup_free(struct mem_cgroup
*mem
)
1669 if (atomic_read(&mem
->refcnt
) > 0)
1673 for_each_node_state(node
, N_POSSIBLE
)
1674 free_mem_cgroup_per_zone_info(mem
, node
);
1676 if (mem_cgroup_size() < PAGE_SIZE
)
1682 static void mem_cgroup_get(struct mem_cgroup
*mem
)
1684 atomic_inc(&mem
->refcnt
);
1687 static void mem_cgroup_put(struct mem_cgroup
*mem
)
1689 if (atomic_dec_and_test(&mem
->refcnt
)) {
1692 mem_cgroup_free(mem
);
1697 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1698 static void __init
enable_swap_cgroup(void)
1700 if (!mem_cgroup_disabled() && really_do_swap_account
)
1701 do_swap_account
= 1;
1704 static void __init
enable_swap_cgroup(void)
1709 static struct cgroup_subsys_state
*
1710 mem_cgroup_create(struct cgroup_subsys
*ss
, struct cgroup
*cont
)
1712 struct mem_cgroup
*mem
;
1715 mem
= mem_cgroup_alloc();
1717 return ERR_PTR(-ENOMEM
);
1719 res_counter_init(&mem
->res
);
1720 res_counter_init(&mem
->memsw
);
1722 for_each_node_state(node
, N_POSSIBLE
)
1723 if (alloc_mem_cgroup_per_zone_info(mem
, node
))
1726 if (cont
->parent
== NULL
)
1727 enable_swap_cgroup();
1731 for_each_node_state(node
, N_POSSIBLE
)
1732 free_mem_cgroup_per_zone_info(mem
, node
);
1733 mem_cgroup_free(mem
);
1734 return ERR_PTR(-ENOMEM
);
1737 static void mem_cgroup_pre_destroy(struct cgroup_subsys
*ss
,
1738 struct cgroup
*cont
)
1740 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1742 mem_cgroup_force_empty(mem
, false);
1745 static void mem_cgroup_destroy(struct cgroup_subsys
*ss
,
1746 struct cgroup
*cont
)
1748 mem_cgroup_free(mem_cgroup_from_cont(cont
));
1751 static int mem_cgroup_populate(struct cgroup_subsys
*ss
,
1752 struct cgroup
*cont
)
1756 ret
= cgroup_add_files(cont
, ss
, mem_cgroup_files
,
1757 ARRAY_SIZE(mem_cgroup_files
));
1760 ret
= register_memsw_files(cont
, ss
);
1764 static void mem_cgroup_move_task(struct cgroup_subsys
*ss
,
1765 struct cgroup
*cont
,
1766 struct cgroup
*old_cont
,
1767 struct task_struct
*p
)
1769 struct mm_struct
*mm
;
1770 struct mem_cgroup
*mem
, *old_mem
;
1772 mm
= get_task_mm(p
);
1776 mem
= mem_cgroup_from_cont(cont
);
1777 old_mem
= mem_cgroup_from_cont(old_cont
);
1780 * Only thread group leaders are allowed to migrate, the mm_struct is
1781 * in effect owned by the leader
1783 if (!thread_group_leader(p
))
1790 struct cgroup_subsys mem_cgroup_subsys
= {
1792 .subsys_id
= mem_cgroup_subsys_id
,
1793 .create
= mem_cgroup_create
,
1794 .pre_destroy
= mem_cgroup_pre_destroy
,
1795 .destroy
= mem_cgroup_destroy
,
1796 .populate
= mem_cgroup_populate
,
1797 .attach
= mem_cgroup_move_task
,
1801 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1803 static int __init
disable_swap_account(char *s
)
1805 really_do_swap_account
= 0;
1808 __setup("noswapaccount", disable_swap_account
);