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?
156 unsigned long last_oom_jiffies
;
160 unsigned int inactive_ratio
;
163 * statistics. This must be placed at the end of memcg.
165 struct mem_cgroup_stat stat
;
169 MEM_CGROUP_CHARGE_TYPE_CACHE
= 0,
170 MEM_CGROUP_CHARGE_TYPE_MAPPED
,
171 MEM_CGROUP_CHARGE_TYPE_SHMEM
, /* used by page migration of shmem */
172 MEM_CGROUP_CHARGE_TYPE_FORCE
, /* used by force_empty */
173 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
, /* for accounting swapcache */
177 /* only for here (for easy reading.) */
178 #define PCGF_CACHE (1UL << PCG_CACHE)
179 #define PCGF_USED (1UL << PCG_USED)
180 #define PCGF_LOCK (1UL << PCG_LOCK)
181 static const unsigned long
182 pcg_default_flags
[NR_CHARGE_TYPE
] = {
183 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* File Cache */
184 PCGF_USED
| PCGF_LOCK
, /* Anon */
185 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* Shmem */
189 /* for encoding cft->private value on file */
192 #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
193 #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
194 #define MEMFILE_ATTR(val) ((val) & 0xffff)
196 static void mem_cgroup_get(struct mem_cgroup
*mem
);
197 static void mem_cgroup_put(struct mem_cgroup
*mem
);
199 static void mem_cgroup_charge_statistics(struct mem_cgroup
*mem
,
200 struct page_cgroup
*pc
,
203 int val
= (charge
)? 1 : -1;
204 struct mem_cgroup_stat
*stat
= &mem
->stat
;
205 struct mem_cgroup_stat_cpu
*cpustat
;
208 cpustat
= &stat
->cpustat
[cpu
];
209 if (PageCgroupCache(pc
))
210 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_CACHE
, val
);
212 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_RSS
, val
);
215 __mem_cgroup_stat_add_safe(cpustat
,
216 MEM_CGROUP_STAT_PGPGIN_COUNT
, 1);
218 __mem_cgroup_stat_add_safe(cpustat
,
219 MEM_CGROUP_STAT_PGPGOUT_COUNT
, 1);
223 static struct mem_cgroup_per_zone
*
224 mem_cgroup_zoneinfo(struct mem_cgroup
*mem
, int nid
, int zid
)
226 return &mem
->info
.nodeinfo
[nid
]->zoneinfo
[zid
];
229 static struct mem_cgroup_per_zone
*
230 page_cgroup_zoneinfo(struct page_cgroup
*pc
)
232 struct mem_cgroup
*mem
= pc
->mem_cgroup
;
233 int nid
= page_cgroup_nid(pc
);
234 int zid
= page_cgroup_zid(pc
);
239 return mem_cgroup_zoneinfo(mem
, nid
, zid
);
242 static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup
*mem
,
246 struct mem_cgroup_per_zone
*mz
;
249 for_each_online_node(nid
)
250 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
251 mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
252 total
+= MEM_CGROUP_ZSTAT(mz
, idx
);
257 static struct mem_cgroup
*mem_cgroup_from_cont(struct cgroup
*cont
)
259 return container_of(cgroup_subsys_state(cont
,
260 mem_cgroup_subsys_id
), struct mem_cgroup
,
264 struct mem_cgroup
*mem_cgroup_from_task(struct task_struct
*p
)
267 * mm_update_next_owner() may clear mm->owner to NULL
268 * if it races with swapoff, page migration, etc.
269 * So this can be called with p == NULL.
274 return container_of(task_subsys_state(p
, mem_cgroup_subsys_id
),
275 struct mem_cgroup
, css
);
279 * Following LRU functions are allowed to be used without PCG_LOCK.
280 * Operations are called by routine of global LRU independently from memcg.
281 * What we have to take care of here is validness of pc->mem_cgroup.
283 * Changes to pc->mem_cgroup happens when
286 * In typical case, "charge" is done before add-to-lru. Exception is SwapCache.
287 * It is added to LRU before charge.
288 * If PCG_USED bit is not set, page_cgroup is not added to this private LRU.
289 * When moving account, the page is not on LRU. It's isolated.
292 void mem_cgroup_del_lru_list(struct page
*page
, enum lru_list lru
)
294 struct page_cgroup
*pc
;
295 struct mem_cgroup
*mem
;
296 struct mem_cgroup_per_zone
*mz
;
298 if (mem_cgroup_disabled())
300 pc
= lookup_page_cgroup(page
);
301 /* can happen while we handle swapcache. */
302 if (list_empty(&pc
->lru
))
304 mz
= page_cgroup_zoneinfo(pc
);
305 mem
= pc
->mem_cgroup
;
306 MEM_CGROUP_ZSTAT(mz
, lru
) -= 1;
307 list_del_init(&pc
->lru
);
311 void mem_cgroup_del_lru(struct page
*page
)
313 mem_cgroup_del_lru_list(page
, page_lru(page
));
316 void mem_cgroup_rotate_lru_list(struct page
*page
, enum lru_list lru
)
318 struct mem_cgroup_per_zone
*mz
;
319 struct page_cgroup
*pc
;
321 if (mem_cgroup_disabled())
324 pc
= lookup_page_cgroup(page
);
326 /* unused page is not rotated. */
327 if (!PageCgroupUsed(pc
))
329 mz
= page_cgroup_zoneinfo(pc
);
330 list_move(&pc
->lru
, &mz
->lists
[lru
]);
333 void mem_cgroup_add_lru_list(struct page
*page
, enum lru_list lru
)
335 struct page_cgroup
*pc
;
336 struct mem_cgroup_per_zone
*mz
;
338 if (mem_cgroup_disabled())
340 pc
= lookup_page_cgroup(page
);
341 /* barrier to sync with "charge" */
343 if (!PageCgroupUsed(pc
))
346 mz
= page_cgroup_zoneinfo(pc
);
347 MEM_CGROUP_ZSTAT(mz
, lru
) += 1;
348 list_add(&pc
->lru
, &mz
->lists
[lru
]);
351 * To add swapcache into LRU. Be careful to all this function.
352 * zone->lru_lock shouldn't be held and irq must not be disabled.
354 static void mem_cgroup_lru_fixup(struct page
*page
)
356 if (!isolate_lru_page(page
))
357 putback_lru_page(page
);
360 void mem_cgroup_move_lists(struct page
*page
,
361 enum lru_list from
, enum lru_list to
)
363 if (mem_cgroup_disabled())
365 mem_cgroup_del_lru_list(page
, from
);
366 mem_cgroup_add_lru_list(page
, to
);
369 int task_in_mem_cgroup(struct task_struct
*task
, const struct mem_cgroup
*mem
)
374 ret
= task
->mm
&& mm_match_cgroup(task
->mm
, mem
);
380 * Calculate mapped_ratio under memory controller. This will be used in
381 * vmscan.c for deteremining we have to reclaim mapped pages.
383 int mem_cgroup_calc_mapped_ratio(struct mem_cgroup
*mem
)
388 * usage is recorded in bytes. But, here, we assume the number of
389 * physical pages can be represented by "long" on any arch.
391 total
= (long) (mem
->res
.usage
>> PAGE_SHIFT
) + 1L;
392 rss
= (long)mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_RSS
);
393 return (int)((rss
* 100L) / total
);
397 * prev_priority control...this will be used in memory reclaim path.
399 int mem_cgroup_get_reclaim_priority(struct mem_cgroup
*mem
)
401 return mem
->prev_priority
;
404 void mem_cgroup_note_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
406 if (priority
< mem
->prev_priority
)
407 mem
->prev_priority
= priority
;
410 void mem_cgroup_record_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
412 mem
->prev_priority
= priority
;
416 * Calculate # of pages to be scanned in this priority/zone.
419 * priority starts from "DEF_PRIORITY" and decremented in each loop.
420 * (see include/linux/mmzone.h)
423 long mem_cgroup_calc_reclaim(struct mem_cgroup
*mem
, struct zone
*zone
,
424 int priority
, enum lru_list lru
)
427 int nid
= zone
->zone_pgdat
->node_id
;
428 int zid
= zone_idx(zone
);
429 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
431 nr_pages
= MEM_CGROUP_ZSTAT(mz
, lru
);
433 return (nr_pages
>> priority
);
436 int mem_cgroup_inactive_anon_is_low(struct mem_cgroup
*memcg
, struct zone
*zone
)
438 unsigned long active
;
439 unsigned long inactive
;
441 inactive
= mem_cgroup_get_all_zonestat(memcg
, LRU_INACTIVE_ANON
);
442 active
= mem_cgroup_get_all_zonestat(memcg
, LRU_ACTIVE_ANON
);
444 if (inactive
* memcg
->inactive_ratio
< active
)
450 unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup
*memcg
,
454 int nid
= zone
->zone_pgdat
->node_id
;
455 int zid
= zone_idx(zone
);
456 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(memcg
, nid
, zid
);
458 return MEM_CGROUP_ZSTAT(mz
, lru
);
461 unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan
,
462 struct list_head
*dst
,
463 unsigned long *scanned
, int order
,
464 int mode
, struct zone
*z
,
465 struct mem_cgroup
*mem_cont
,
466 int active
, int file
)
468 unsigned long nr_taken
= 0;
472 struct list_head
*src
;
473 struct page_cgroup
*pc
, *tmp
;
474 int nid
= z
->zone_pgdat
->node_id
;
475 int zid
= zone_idx(z
);
476 struct mem_cgroup_per_zone
*mz
;
477 int lru
= LRU_FILE
* !!file
+ !!active
;
480 mz
= mem_cgroup_zoneinfo(mem_cont
, nid
, zid
);
481 src
= &mz
->lists
[lru
];
484 list_for_each_entry_safe_reverse(pc
, tmp
, src
, lru
) {
485 if (scan
>= nr_to_scan
)
489 if (unlikely(!PageCgroupUsed(pc
)))
491 if (unlikely(!PageLRU(page
)))
495 if (__isolate_lru_page(page
, mode
, file
) == 0) {
496 list_move(&page
->lru
, dst
);
505 #define mem_cgroup_from_res_counter(counter, member) \
506 container_of(counter, struct mem_cgroup, member)
509 * This routine finds the DFS walk successor. This routine should be
510 * called with cgroup_mutex held
512 static struct mem_cgroup
*
513 mem_cgroup_get_next_node(struct mem_cgroup
*curr
, struct mem_cgroup
*root_mem
)
515 struct cgroup
*cgroup
, *curr_cgroup
, *root_cgroup
;
517 curr_cgroup
= curr
->css
.cgroup
;
518 root_cgroup
= root_mem
->css
.cgroup
;
520 if (!list_empty(&curr_cgroup
->children
)) {
522 * Walk down to children
524 mem_cgroup_put(curr
);
525 cgroup
= list_entry(curr_cgroup
->children
.next
,
526 struct cgroup
, sibling
);
527 curr
= mem_cgroup_from_cont(cgroup
);
528 mem_cgroup_get(curr
);
533 if (curr_cgroup
== root_cgroup
) {
534 mem_cgroup_put(curr
);
536 mem_cgroup_get(curr
);
543 if (curr_cgroup
->sibling
.next
!= &curr_cgroup
->parent
->children
) {
544 mem_cgroup_put(curr
);
545 cgroup
= list_entry(curr_cgroup
->sibling
.next
, struct cgroup
,
547 curr
= mem_cgroup_from_cont(cgroup
);
548 mem_cgroup_get(curr
);
553 * Go up to next parent and next parent's sibling if need be
555 curr_cgroup
= curr_cgroup
->parent
;
559 root_mem
->last_scanned_child
= curr
;
564 * Visit the first child (need not be the first child as per the ordering
565 * of the cgroup list, since we track last_scanned_child) of @mem and use
566 * that to reclaim free pages from.
568 static struct mem_cgroup
*
569 mem_cgroup_get_first_node(struct mem_cgroup
*root_mem
)
571 struct cgroup
*cgroup
;
572 struct mem_cgroup
*ret
;
573 bool obsolete
= (root_mem
->last_scanned_child
&&
574 root_mem
->last_scanned_child
->obsolete
);
577 * Scan all children under the mem_cgroup mem
580 if (list_empty(&root_mem
->css
.cgroup
->children
)) {
585 if (!root_mem
->last_scanned_child
|| obsolete
) {
588 mem_cgroup_put(root_mem
->last_scanned_child
);
590 cgroup
= list_first_entry(&root_mem
->css
.cgroup
->children
,
591 struct cgroup
, sibling
);
592 ret
= mem_cgroup_from_cont(cgroup
);
595 ret
= mem_cgroup_get_next_node(root_mem
->last_scanned_child
,
599 root_mem
->last_scanned_child
= ret
;
604 static bool mem_cgroup_check_under_limit(struct mem_cgroup
*mem
)
606 if (do_swap_account
) {
607 if (res_counter_check_under_limit(&mem
->res
) &&
608 res_counter_check_under_limit(&mem
->memsw
))
611 if (res_counter_check_under_limit(&mem
->res
))
617 * Dance down the hierarchy if needed to reclaim memory. We remember the
618 * last child we reclaimed from, so that we don't end up penalizing
619 * one child extensively based on its position in the children list.
621 * root_mem is the original ancestor that we've been reclaim from.
623 static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup
*root_mem
,
624 gfp_t gfp_mask
, bool noswap
)
626 struct mem_cgroup
*next_mem
;
630 * Reclaim unconditionally and don't check for return value.
631 * We need to reclaim in the current group and down the tree.
632 * One might think about checking for children before reclaiming,
633 * but there might be left over accounting, even after children
636 ret
= try_to_free_mem_cgroup_pages(root_mem
, gfp_mask
, noswap
);
637 if (mem_cgroup_check_under_limit(root_mem
))
639 if (!root_mem
->use_hierarchy
)
642 next_mem
= mem_cgroup_get_first_node(root_mem
);
644 while (next_mem
!= root_mem
) {
645 if (next_mem
->obsolete
) {
646 mem_cgroup_put(next_mem
);
648 next_mem
= mem_cgroup_get_first_node(root_mem
);
652 ret
= try_to_free_mem_cgroup_pages(next_mem
, gfp_mask
, noswap
);
653 if (mem_cgroup_check_under_limit(root_mem
))
656 next_mem
= mem_cgroup_get_next_node(next_mem
, root_mem
);
662 bool mem_cgroup_oom_called(struct task_struct
*task
)
665 struct mem_cgroup
*mem
;
666 struct mm_struct
*mm
;
672 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
673 if (mem
&& time_before(jiffies
, mem
->last_oom_jiffies
+ HZ
/10))
679 * Unlike exported interface, "oom" parameter is added. if oom==true,
680 * oom-killer can be invoked.
682 static int __mem_cgroup_try_charge(struct mm_struct
*mm
,
683 gfp_t gfp_mask
, struct mem_cgroup
**memcg
,
686 struct mem_cgroup
*mem
, *mem_over_limit
;
687 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
688 struct res_counter
*fail_res
;
690 if (unlikely(test_thread_flag(TIF_MEMDIE
))) {
691 /* Don't account this! */
697 * We always charge the cgroup the mm_struct belongs to.
698 * The mm_struct's mem_cgroup changes on task migration if the
699 * thread group leader migrates. It's possible that mm is not
700 * set, if so charge the init_mm (happens for pagecache usage).
702 if (likely(!*memcg
)) {
704 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
705 if (unlikely(!mem
)) {
710 * For every charge from the cgroup, increment reference count
724 ret
= res_counter_charge(&mem
->res
, PAGE_SIZE
, &fail_res
);
726 if (!do_swap_account
)
728 ret
= res_counter_charge(&mem
->memsw
, PAGE_SIZE
,
732 /* mem+swap counter fails */
733 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
735 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
738 /* mem counter fails */
739 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
742 if (!(gfp_mask
& __GFP_WAIT
))
745 ret
= mem_cgroup_hierarchical_reclaim(mem_over_limit
, gfp_mask
,
749 * try_to_free_mem_cgroup_pages() might not give us a full
750 * picture of reclaim. Some pages are reclaimed and might be
751 * moved to swap cache or just unmapped from the cgroup.
752 * Check the limit again to see if the reclaim reduced the
753 * current usage of the cgroup before giving up
756 if (mem_cgroup_check_under_limit(mem_over_limit
))
761 mem_cgroup_out_of_memory(mem_over_limit
, gfp_mask
);
762 mem_over_limit
->last_oom_jiffies
= jiffies
;
774 * mem_cgroup_try_charge - get charge of PAGE_SIZE.
775 * @mm: an mm_struct which is charged against. (when *memcg is NULL)
776 * @gfp_mask: gfp_mask for reclaim.
777 * @memcg: a pointer to memory cgroup which is charged against.
779 * charge against memory cgroup pointed by *memcg. if *memcg == NULL, estimated
780 * memory cgroup from @mm is got and stored in *memcg.
782 * Returns 0 if success. -ENOMEM at failure.
783 * This call can invoke OOM-Killer.
786 int mem_cgroup_try_charge(struct mm_struct
*mm
,
787 gfp_t mask
, struct mem_cgroup
**memcg
)
789 return __mem_cgroup_try_charge(mm
, mask
, memcg
, true);
793 * commit a charge got by mem_cgroup_try_charge() and makes page_cgroup to be
794 * USED state. If already USED, uncharge and return.
797 static void __mem_cgroup_commit_charge(struct mem_cgroup
*mem
,
798 struct page_cgroup
*pc
,
799 enum charge_type ctype
)
801 /* try_charge() can return NULL to *memcg, taking care of it. */
805 lock_page_cgroup(pc
);
806 if (unlikely(PageCgroupUsed(pc
))) {
807 unlock_page_cgroup(pc
);
808 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
810 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
814 pc
->mem_cgroup
= mem
;
816 pc
->flags
= pcg_default_flags
[ctype
];
818 mem_cgroup_charge_statistics(mem
, pc
, true);
820 unlock_page_cgroup(pc
);
824 * mem_cgroup_move_account - move account of the page
825 * @pc: page_cgroup of the page.
826 * @from: mem_cgroup which the page is moved from.
827 * @to: mem_cgroup which the page is moved to. @from != @to.
829 * The caller must confirm following.
830 * - page is not on LRU (isolate_page() is useful.)
832 * returns 0 at success,
833 * returns -EBUSY when lock is busy or "pc" is unstable.
835 * This function does "uncharge" from old cgroup but doesn't do "charge" to
836 * new cgroup. It should be done by a caller.
839 static int mem_cgroup_move_account(struct page_cgroup
*pc
,
840 struct mem_cgroup
*from
, struct mem_cgroup
*to
)
842 struct mem_cgroup_per_zone
*from_mz
, *to_mz
;
846 VM_BUG_ON(from
== to
);
847 VM_BUG_ON(PageLRU(pc
->page
));
849 nid
= page_cgroup_nid(pc
);
850 zid
= page_cgroup_zid(pc
);
851 from_mz
= mem_cgroup_zoneinfo(from
, nid
, zid
);
852 to_mz
= mem_cgroup_zoneinfo(to
, nid
, zid
);
854 if (!trylock_page_cgroup(pc
))
857 if (!PageCgroupUsed(pc
))
860 if (pc
->mem_cgroup
!= from
)
864 res_counter_uncharge(&from
->res
, PAGE_SIZE
);
865 mem_cgroup_charge_statistics(from
, pc
, false);
867 res_counter_uncharge(&from
->memsw
, PAGE_SIZE
);
869 mem_cgroup_charge_statistics(to
, pc
, true);
873 unlock_page_cgroup(pc
);
878 * move charges to its parent.
881 static int mem_cgroup_move_parent(struct page_cgroup
*pc
,
882 struct mem_cgroup
*child
,
885 struct page
*page
= pc
->page
;
886 struct cgroup
*cg
= child
->css
.cgroup
;
887 struct cgroup
*pcg
= cg
->parent
;
888 struct mem_cgroup
*parent
;
896 parent
= mem_cgroup_from_cont(pcg
);
899 ret
= __mem_cgroup_try_charge(NULL
, gfp_mask
, &parent
, false);
903 if (!get_page_unless_zero(page
))
906 ret
= isolate_lru_page(page
);
911 ret
= mem_cgroup_move_account(pc
, child
, parent
);
913 /* drop extra refcnt by try_charge() (move_account increment one) */
914 css_put(&parent
->css
);
915 putback_lru_page(page
);
920 /* uncharge if move fails */
922 res_counter_uncharge(&parent
->res
, PAGE_SIZE
);
924 res_counter_uncharge(&parent
->memsw
, PAGE_SIZE
);
930 * Charge the memory controller for page usage.
932 * 0 if the charge was successful
933 * < 0 if the cgroup is over its limit
935 static int mem_cgroup_charge_common(struct page
*page
, struct mm_struct
*mm
,
936 gfp_t gfp_mask
, enum charge_type ctype
,
937 struct mem_cgroup
*memcg
)
939 struct mem_cgroup
*mem
;
940 struct page_cgroup
*pc
;
943 pc
= lookup_page_cgroup(page
);
944 /* can happen at boot */
950 ret
= __mem_cgroup_try_charge(mm
, gfp_mask
, &mem
, true);
954 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
958 int mem_cgroup_newpage_charge(struct page
*page
,
959 struct mm_struct
*mm
, gfp_t gfp_mask
)
961 if (mem_cgroup_disabled())
963 if (PageCompound(page
))
966 * If already mapped, we don't have to account.
967 * If page cache, page->mapping has address_space.
968 * But page->mapping may have out-of-use anon_vma pointer,
969 * detecit it by PageAnon() check. newly-mapped-anon's page->mapping
972 if (page_mapped(page
) || (page
->mapping
&& !PageAnon(page
)))
976 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
977 MEM_CGROUP_CHARGE_TYPE_MAPPED
, NULL
);
980 int mem_cgroup_cache_charge(struct page
*page
, struct mm_struct
*mm
,
983 if (mem_cgroup_disabled())
985 if (PageCompound(page
))
988 * Corner case handling. This is called from add_to_page_cache()
989 * in usual. But some FS (shmem) precharges this page before calling it
990 * and call add_to_page_cache() with GFP_NOWAIT.
992 * For GFP_NOWAIT case, the page may be pre-charged before calling
993 * add_to_page_cache(). (See shmem.c) check it here and avoid to call
994 * charge twice. (It works but has to pay a bit larger cost.)
996 if (!(gfp_mask
& __GFP_WAIT
)) {
997 struct page_cgroup
*pc
;
1000 pc
= lookup_page_cgroup(page
);
1003 lock_page_cgroup(pc
);
1004 if (PageCgroupUsed(pc
)) {
1005 unlock_page_cgroup(pc
);
1008 unlock_page_cgroup(pc
);
1014 if (page_is_file_cache(page
))
1015 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1016 MEM_CGROUP_CHARGE_TYPE_CACHE
, NULL
);
1018 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1019 MEM_CGROUP_CHARGE_TYPE_SHMEM
, NULL
);
1022 int mem_cgroup_try_charge_swapin(struct mm_struct
*mm
,
1024 gfp_t mask
, struct mem_cgroup
**ptr
)
1026 struct mem_cgroup
*mem
;
1029 if (mem_cgroup_disabled())
1032 if (!do_swap_account
)
1036 * A racing thread's fault, or swapoff, may have already updated
1037 * the pte, and even removed page from swap cache: return success
1038 * to go on to do_swap_page()'s pte_same() test, which should fail.
1040 if (!PageSwapCache(page
))
1043 ent
.val
= page_private(page
);
1045 mem
= lookup_swap_cgroup(ent
);
1046 if (!mem
|| mem
->obsolete
)
1049 return __mem_cgroup_try_charge(NULL
, mask
, ptr
, true);
1053 return __mem_cgroup_try_charge(mm
, mask
, ptr
, true);
1058 int mem_cgroup_cache_charge_swapin(struct page
*page
,
1059 struct mm_struct
*mm
, gfp_t mask
, bool locked
)
1063 if (mem_cgroup_disabled())
1070 * If not locked, the page can be dropped from SwapCache until
1073 if (PageSwapCache(page
)) {
1074 struct mem_cgroup
*mem
= NULL
;
1077 ent
.val
= page_private(page
);
1078 if (do_swap_account
) {
1079 mem
= lookup_swap_cgroup(ent
);
1080 if (mem
&& mem
->obsolete
)
1085 ret
= mem_cgroup_charge_common(page
, mm
, mask
,
1086 MEM_CGROUP_CHARGE_TYPE_SHMEM
, mem
);
1088 if (!ret
&& do_swap_account
) {
1089 /* avoid double counting */
1090 mem
= swap_cgroup_record(ent
, NULL
);
1092 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1093 mem_cgroup_put(mem
);
1099 /* add this page(page_cgroup) to the LRU we want. */
1100 mem_cgroup_lru_fixup(page
);
1106 void mem_cgroup_commit_charge_swapin(struct page
*page
, struct mem_cgroup
*ptr
)
1108 struct page_cgroup
*pc
;
1110 if (mem_cgroup_disabled())
1114 pc
= lookup_page_cgroup(page
);
1115 __mem_cgroup_commit_charge(ptr
, pc
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1117 * Now swap is on-memory. This means this page may be
1118 * counted both as mem and swap....double count.
1119 * Fix it by uncharging from memsw. This SwapCache is stable
1120 * because we're still under lock_page().
1122 if (do_swap_account
) {
1123 swp_entry_t ent
= {.val
= page_private(page
)};
1124 struct mem_cgroup
*memcg
;
1125 memcg
= swap_cgroup_record(ent
, NULL
);
1127 /* If memcg is obsolete, memcg can be != ptr */
1128 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1129 mem_cgroup_put(memcg
);
1133 /* add this page(page_cgroup) to the LRU we want. */
1134 mem_cgroup_lru_fixup(page
);
1137 void mem_cgroup_cancel_charge_swapin(struct mem_cgroup
*mem
)
1139 if (mem_cgroup_disabled())
1143 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1144 if (do_swap_account
)
1145 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1151 * uncharge if !page_mapped(page)
1153 static struct mem_cgroup
*
1154 __mem_cgroup_uncharge_common(struct page
*page
, enum charge_type ctype
)
1156 struct page_cgroup
*pc
;
1157 struct mem_cgroup
*mem
= NULL
;
1158 struct mem_cgroup_per_zone
*mz
;
1160 if (mem_cgroup_disabled())
1163 if (PageSwapCache(page
))
1167 * Check if our page_cgroup is valid
1169 pc
= lookup_page_cgroup(page
);
1170 if (unlikely(!pc
|| !PageCgroupUsed(pc
)))
1173 lock_page_cgroup(pc
);
1175 mem
= pc
->mem_cgroup
;
1177 if (!PageCgroupUsed(pc
))
1181 case MEM_CGROUP_CHARGE_TYPE_MAPPED
:
1182 if (page_mapped(page
))
1185 case MEM_CGROUP_CHARGE_TYPE_SWAPOUT
:
1186 if (!PageAnon(page
)) { /* Shared memory */
1187 if (page
->mapping
&& !page_is_file_cache(page
))
1189 } else if (page_mapped(page
)) /* Anon */
1196 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1197 if (do_swap_account
&& (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
))
1198 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1200 mem_cgroup_charge_statistics(mem
, pc
, false);
1201 ClearPageCgroupUsed(pc
);
1203 mz
= page_cgroup_zoneinfo(pc
);
1204 unlock_page_cgroup(pc
);
1206 /* at swapout, this memcg will be accessed to record to swap */
1207 if (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
)
1213 unlock_page_cgroup(pc
);
1217 void mem_cgroup_uncharge_page(struct page
*page
)
1220 if (page_mapped(page
))
1222 if (page
->mapping
&& !PageAnon(page
))
1224 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1227 void mem_cgroup_uncharge_cache_page(struct page
*page
)
1229 VM_BUG_ON(page_mapped(page
));
1230 VM_BUG_ON(page
->mapping
);
1231 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_CACHE
);
1235 * called from __delete_from_swap_cache() and drop "page" account.
1236 * memcg information is recorded to swap_cgroup of "ent"
1238 void mem_cgroup_uncharge_swapcache(struct page
*page
, swp_entry_t ent
)
1240 struct mem_cgroup
*memcg
;
1242 memcg
= __mem_cgroup_uncharge_common(page
,
1243 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
);
1244 /* record memcg information */
1245 if (do_swap_account
&& memcg
) {
1246 swap_cgroup_record(ent
, memcg
);
1247 mem_cgroup_get(memcg
);
1250 css_put(&memcg
->css
);
1253 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1255 * called from swap_entry_free(). remove record in swap_cgroup and
1256 * uncharge "memsw" account.
1258 void mem_cgroup_uncharge_swap(swp_entry_t ent
)
1260 struct mem_cgroup
*memcg
;
1262 if (!do_swap_account
)
1265 memcg
= swap_cgroup_record(ent
, NULL
);
1267 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1268 mem_cgroup_put(memcg
);
1274 * Before starting migration, account PAGE_SIZE to mem_cgroup that the old
1277 int mem_cgroup_prepare_migration(struct page
*page
, struct mem_cgroup
**ptr
)
1279 struct page_cgroup
*pc
;
1280 struct mem_cgroup
*mem
= NULL
;
1283 if (mem_cgroup_disabled())
1286 pc
= lookup_page_cgroup(page
);
1287 lock_page_cgroup(pc
);
1288 if (PageCgroupUsed(pc
)) {
1289 mem
= pc
->mem_cgroup
;
1292 unlock_page_cgroup(pc
);
1295 ret
= mem_cgroup_try_charge(NULL
, GFP_KERNEL
, &mem
);
1302 /* remove redundant charge if migration failed*/
1303 void mem_cgroup_end_migration(struct mem_cgroup
*mem
,
1304 struct page
*oldpage
, struct page
*newpage
)
1306 struct page
*target
, *unused
;
1307 struct page_cgroup
*pc
;
1308 enum charge_type ctype
;
1313 /* at migration success, oldpage->mapping is NULL. */
1314 if (oldpage
->mapping
) {
1322 if (PageAnon(target
))
1323 ctype
= MEM_CGROUP_CHARGE_TYPE_MAPPED
;
1324 else if (page_is_file_cache(target
))
1325 ctype
= MEM_CGROUP_CHARGE_TYPE_CACHE
;
1327 ctype
= MEM_CGROUP_CHARGE_TYPE_SHMEM
;
1329 /* unused page is not on radix-tree now. */
1331 __mem_cgroup_uncharge_common(unused
, ctype
);
1333 pc
= lookup_page_cgroup(target
);
1335 * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
1336 * So, double-counting is effectively avoided.
1338 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
1341 * Both of oldpage and newpage are still under lock_page().
1342 * Then, we don't have to care about race in radix-tree.
1343 * But we have to be careful that this page is unmapped or not.
1345 * There is a case for !page_mapped(). At the start of
1346 * migration, oldpage was mapped. But now, it's zapped.
1347 * But we know *target* page is not freed/reused under us.
1348 * mem_cgroup_uncharge_page() does all necessary checks.
1350 if (ctype
== MEM_CGROUP_CHARGE_TYPE_MAPPED
)
1351 mem_cgroup_uncharge_page(target
);
1355 * A call to try to shrink memory usage under specified resource controller.
1356 * This is typically used for page reclaiming for shmem for reducing side
1357 * effect of page allocation from shmem, which is used by some mem_cgroup.
1359 int mem_cgroup_shrink_usage(struct mm_struct
*mm
, gfp_t gfp_mask
)
1361 struct mem_cgroup
*mem
;
1363 int retry
= MEM_CGROUP_RECLAIM_RETRIES
;
1365 if (mem_cgroup_disabled())
1371 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
1372 if (unlikely(!mem
)) {
1380 progress
= try_to_free_mem_cgroup_pages(mem
, gfp_mask
, true);
1381 progress
+= mem_cgroup_check_under_limit(mem
);
1382 } while (!progress
&& --retry
);
1391 * The inactive anon list should be small enough that the VM never has to
1392 * do too much work, but large enough that each inactive page has a chance
1393 * to be referenced again before it is swapped out.
1395 * this calculation is straightforward porting from
1396 * page_alloc.c::setup_per_zone_inactive_ratio().
1397 * it describe more detail.
1399 static void mem_cgroup_set_inactive_ratio(struct mem_cgroup
*memcg
)
1401 unsigned int gb
, ratio
;
1403 gb
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
) >> 30;
1405 ratio
= int_sqrt(10 * gb
);
1409 memcg
->inactive_ratio
= ratio
;
1413 static DEFINE_MUTEX(set_limit_mutex
);
1415 static int mem_cgroup_resize_limit(struct mem_cgroup
*memcg
,
1416 unsigned long long val
)
1419 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1424 while (retry_count
) {
1425 if (signal_pending(current
)) {
1430 * Rather than hide all in some function, I do this in
1431 * open coded manner. You see what this really does.
1432 * We have to guarantee mem->res.limit < mem->memsw.limit.
1434 mutex_lock(&set_limit_mutex
);
1435 memswlimit
= res_counter_read_u64(&memcg
->memsw
, RES_LIMIT
);
1436 if (memswlimit
< val
) {
1438 mutex_unlock(&set_limit_mutex
);
1441 ret
= res_counter_set_limit(&memcg
->res
, val
);
1442 mutex_unlock(&set_limit_mutex
);
1447 progress
= try_to_free_mem_cgroup_pages(memcg
,
1449 if (!progress
) retry_count
--;
1453 mem_cgroup_set_inactive_ratio(memcg
);
1458 int mem_cgroup_resize_memsw_limit(struct mem_cgroup
*memcg
,
1459 unsigned long long val
)
1461 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1462 u64 memlimit
, oldusage
, curusage
;
1465 if (!do_swap_account
)
1468 while (retry_count
) {
1469 if (signal_pending(current
)) {
1474 * Rather than hide all in some function, I do this in
1475 * open coded manner. You see what this really does.
1476 * We have to guarantee mem->res.limit < mem->memsw.limit.
1478 mutex_lock(&set_limit_mutex
);
1479 memlimit
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
);
1480 if (memlimit
> val
) {
1482 mutex_unlock(&set_limit_mutex
);
1485 ret
= res_counter_set_limit(&memcg
->memsw
, val
);
1486 mutex_unlock(&set_limit_mutex
);
1491 oldusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1492 try_to_free_mem_cgroup_pages(memcg
, GFP_KERNEL
, true);
1493 curusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1494 if (curusage
>= oldusage
)
1501 * This routine traverse page_cgroup in given list and drop them all.
1502 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
1504 static int mem_cgroup_force_empty_list(struct mem_cgroup
*mem
,
1505 int node
, int zid
, enum lru_list lru
)
1508 struct mem_cgroup_per_zone
*mz
;
1509 struct page_cgroup
*pc
, *busy
;
1510 unsigned long flags
, loop
;
1511 struct list_head
*list
;
1514 zone
= &NODE_DATA(node
)->node_zones
[zid
];
1515 mz
= mem_cgroup_zoneinfo(mem
, node
, zid
);
1516 list
= &mz
->lists
[lru
];
1518 loop
= MEM_CGROUP_ZSTAT(mz
, lru
);
1519 /* give some margin against EBUSY etc...*/
1524 spin_lock_irqsave(&zone
->lru_lock
, flags
);
1525 if (list_empty(list
)) {
1526 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1529 pc
= list_entry(list
->prev
, struct page_cgroup
, lru
);
1531 list_move(&pc
->lru
, list
);
1533 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1536 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1538 ret
= mem_cgroup_move_parent(pc
, mem
, GFP_KERNEL
);
1542 if (ret
== -EBUSY
|| ret
== -EINVAL
) {
1543 /* found lock contention or "pc" is obsolete. */
1550 if (!ret
&& !list_empty(list
))
1556 * make mem_cgroup's charge to be 0 if there is no task.
1557 * This enables deleting this mem_cgroup.
1559 static int mem_cgroup_force_empty(struct mem_cgroup
*mem
, bool free_all
)
1562 int node
, zid
, shrink
;
1563 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
1564 struct cgroup
*cgrp
= mem
->css
.cgroup
;
1569 /* should free all ? */
1573 while (mem
->res
.usage
> 0) {
1575 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
))
1578 if (signal_pending(current
))
1580 /* This is for making all *used* pages to be on LRU. */
1581 lru_add_drain_all();
1583 for_each_node_state(node
, N_POSSIBLE
) {
1584 for (zid
= 0; !ret
&& zid
< MAX_NR_ZONES
; zid
++) {
1587 ret
= mem_cgroup_force_empty_list(mem
,
1596 /* it seems parent cgroup doesn't have enough mem */
1607 /* returns EBUSY if there is a task or if we come here twice. */
1608 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
) || shrink
) {
1612 /* we call try-to-free pages for make this cgroup empty */
1613 lru_add_drain_all();
1614 /* try to free all pages in this cgroup */
1616 while (nr_retries
&& mem
->res
.usage
> 0) {
1619 if (signal_pending(current
)) {
1623 progress
= try_to_free_mem_cgroup_pages(mem
,
1627 /* maybe some writeback is necessary */
1628 congestion_wait(WRITE
, HZ
/10);
1633 /* try move_account...there may be some *locked* pages. */
1640 int mem_cgroup_force_empty_write(struct cgroup
*cont
, unsigned int event
)
1642 return mem_cgroup_force_empty(mem_cgroup_from_cont(cont
), true);
1646 static u64
mem_cgroup_hierarchy_read(struct cgroup
*cont
, struct cftype
*cft
)
1648 return mem_cgroup_from_cont(cont
)->use_hierarchy
;
1651 static int mem_cgroup_hierarchy_write(struct cgroup
*cont
, struct cftype
*cft
,
1655 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1656 struct cgroup
*parent
= cont
->parent
;
1657 struct mem_cgroup
*parent_mem
= NULL
;
1660 parent_mem
= mem_cgroup_from_cont(parent
);
1664 * If parent's use_hiearchy is set, we can't make any modifications
1665 * in the child subtrees. If it is unset, then the change can
1666 * occur, provided the current cgroup has no children.
1668 * For the root cgroup, parent_mem is NULL, we allow value to be
1669 * set if there are no children.
1671 if ((!parent_mem
|| !parent_mem
->use_hierarchy
) &&
1672 (val
== 1 || val
== 0)) {
1673 if (list_empty(&cont
->children
))
1674 mem
->use_hierarchy
= val
;
1684 static u64
mem_cgroup_read(struct cgroup
*cont
, struct cftype
*cft
)
1686 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1690 type
= MEMFILE_TYPE(cft
->private);
1691 name
= MEMFILE_ATTR(cft
->private);
1694 val
= res_counter_read_u64(&mem
->res
, name
);
1697 if (do_swap_account
)
1698 val
= res_counter_read_u64(&mem
->memsw
, name
);
1707 * The user of this function is...
1710 static int mem_cgroup_write(struct cgroup
*cont
, struct cftype
*cft
,
1713 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cont
);
1715 unsigned long long val
;
1718 type
= MEMFILE_TYPE(cft
->private);
1719 name
= MEMFILE_ATTR(cft
->private);
1722 /* This function does all necessary parse...reuse it */
1723 ret
= res_counter_memparse_write_strategy(buffer
, &val
);
1727 ret
= mem_cgroup_resize_limit(memcg
, val
);
1729 ret
= mem_cgroup_resize_memsw_limit(memcg
, val
);
1732 ret
= -EINVAL
; /* should be BUG() ? */
1738 static int mem_cgroup_reset(struct cgroup
*cont
, unsigned int event
)
1740 struct mem_cgroup
*mem
;
1743 mem
= mem_cgroup_from_cont(cont
);
1744 type
= MEMFILE_TYPE(event
);
1745 name
= MEMFILE_ATTR(event
);
1749 res_counter_reset_max(&mem
->res
);
1751 res_counter_reset_max(&mem
->memsw
);
1755 res_counter_reset_failcnt(&mem
->res
);
1757 res_counter_reset_failcnt(&mem
->memsw
);
1763 static const struct mem_cgroup_stat_desc
{
1766 } mem_cgroup_stat_desc
[] = {
1767 [MEM_CGROUP_STAT_CACHE
] = { "cache", PAGE_SIZE
, },
1768 [MEM_CGROUP_STAT_RSS
] = { "rss", PAGE_SIZE
, },
1769 [MEM_CGROUP_STAT_PGPGIN_COUNT
] = {"pgpgin", 1, },
1770 [MEM_CGROUP_STAT_PGPGOUT_COUNT
] = {"pgpgout", 1, },
1773 static int mem_control_stat_show(struct cgroup
*cont
, struct cftype
*cft
,
1774 struct cgroup_map_cb
*cb
)
1776 struct mem_cgroup
*mem_cont
= mem_cgroup_from_cont(cont
);
1777 struct mem_cgroup_stat
*stat
= &mem_cont
->stat
;
1780 for (i
= 0; i
< ARRAY_SIZE(stat
->cpustat
[0].count
); i
++) {
1783 val
= mem_cgroup_read_stat(stat
, i
);
1784 val
*= mem_cgroup_stat_desc
[i
].unit
;
1785 cb
->fill(cb
, mem_cgroup_stat_desc
[i
].msg
, val
);
1787 /* showing # of active pages */
1789 unsigned long active_anon
, inactive_anon
;
1790 unsigned long active_file
, inactive_file
;
1791 unsigned long unevictable
;
1793 inactive_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1795 active_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1797 inactive_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1799 active_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1801 unevictable
= mem_cgroup_get_all_zonestat(mem_cont
,
1804 cb
->fill(cb
, "active_anon", (active_anon
) * PAGE_SIZE
);
1805 cb
->fill(cb
, "inactive_anon", (inactive_anon
) * PAGE_SIZE
);
1806 cb
->fill(cb
, "active_file", (active_file
) * PAGE_SIZE
);
1807 cb
->fill(cb
, "inactive_file", (inactive_file
) * PAGE_SIZE
);
1808 cb
->fill(cb
, "unevictable", unevictable
* PAGE_SIZE
);
1815 static struct cftype mem_cgroup_files
[] = {
1817 .name
= "usage_in_bytes",
1818 .private = MEMFILE_PRIVATE(_MEM
, RES_USAGE
),
1819 .read_u64
= mem_cgroup_read
,
1822 .name
= "max_usage_in_bytes",
1823 .private = MEMFILE_PRIVATE(_MEM
, RES_MAX_USAGE
),
1824 .trigger
= mem_cgroup_reset
,
1825 .read_u64
= mem_cgroup_read
,
1828 .name
= "limit_in_bytes",
1829 .private = MEMFILE_PRIVATE(_MEM
, RES_LIMIT
),
1830 .write_string
= mem_cgroup_write
,
1831 .read_u64
= mem_cgroup_read
,
1835 .private = MEMFILE_PRIVATE(_MEM
, RES_FAILCNT
),
1836 .trigger
= mem_cgroup_reset
,
1837 .read_u64
= mem_cgroup_read
,
1841 .read_map
= mem_control_stat_show
,
1844 .name
= "force_empty",
1845 .trigger
= mem_cgroup_force_empty_write
,
1848 .name
= "use_hierarchy",
1849 .write_u64
= mem_cgroup_hierarchy_write
,
1850 .read_u64
= mem_cgroup_hierarchy_read
,
1854 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1855 static struct cftype memsw_cgroup_files
[] = {
1857 .name
= "memsw.usage_in_bytes",
1858 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_USAGE
),
1859 .read_u64
= mem_cgroup_read
,
1862 .name
= "memsw.max_usage_in_bytes",
1863 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_MAX_USAGE
),
1864 .trigger
= mem_cgroup_reset
,
1865 .read_u64
= mem_cgroup_read
,
1868 .name
= "memsw.limit_in_bytes",
1869 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_LIMIT
),
1870 .write_string
= mem_cgroup_write
,
1871 .read_u64
= mem_cgroup_read
,
1874 .name
= "memsw.failcnt",
1875 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_FAILCNT
),
1876 .trigger
= mem_cgroup_reset
,
1877 .read_u64
= mem_cgroup_read
,
1881 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1883 if (!do_swap_account
)
1885 return cgroup_add_files(cont
, ss
, memsw_cgroup_files
,
1886 ARRAY_SIZE(memsw_cgroup_files
));
1889 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1895 static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
1897 struct mem_cgroup_per_node
*pn
;
1898 struct mem_cgroup_per_zone
*mz
;
1900 int zone
, tmp
= node
;
1902 * This routine is called against possible nodes.
1903 * But it's BUG to call kmalloc() against offline node.
1905 * TODO: this routine can waste much memory for nodes which will
1906 * never be onlined. It's better to use memory hotplug callback
1909 if (!node_state(node
, N_NORMAL_MEMORY
))
1911 pn
= kmalloc_node(sizeof(*pn
), GFP_KERNEL
, tmp
);
1915 mem
->info
.nodeinfo
[node
] = pn
;
1916 memset(pn
, 0, sizeof(*pn
));
1918 for (zone
= 0; zone
< MAX_NR_ZONES
; zone
++) {
1919 mz
= &pn
->zoneinfo
[zone
];
1921 INIT_LIST_HEAD(&mz
->lists
[l
]);
1926 static void free_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
1928 kfree(mem
->info
.nodeinfo
[node
]);
1931 static int mem_cgroup_size(void)
1933 int cpustat_size
= nr_cpu_ids
* sizeof(struct mem_cgroup_stat_cpu
);
1934 return sizeof(struct mem_cgroup
) + cpustat_size
;
1937 static struct mem_cgroup
*mem_cgroup_alloc(void)
1939 struct mem_cgroup
*mem
;
1940 int size
= mem_cgroup_size();
1942 if (size
< PAGE_SIZE
)
1943 mem
= kmalloc(size
, GFP_KERNEL
);
1945 mem
= vmalloc(size
);
1948 memset(mem
, 0, size
);
1953 * At destroying mem_cgroup, references from swap_cgroup can remain.
1954 * (scanning all at force_empty is too costly...)
1956 * Instead of clearing all references at force_empty, we remember
1957 * the number of reference from swap_cgroup and free mem_cgroup when
1958 * it goes down to 0.
1960 * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and
1961 * entry which points to this memcg will be ignore at swapin.
1963 * Removal of cgroup itself succeeds regardless of refs from swap.
1966 static void mem_cgroup_free(struct mem_cgroup
*mem
)
1970 if (atomic_read(&mem
->refcnt
) > 0)
1974 for_each_node_state(node
, N_POSSIBLE
)
1975 free_mem_cgroup_per_zone_info(mem
, node
);
1977 if (mem_cgroup_size() < PAGE_SIZE
)
1983 static void mem_cgroup_get(struct mem_cgroup
*mem
)
1985 atomic_inc(&mem
->refcnt
);
1988 static void mem_cgroup_put(struct mem_cgroup
*mem
)
1990 if (atomic_dec_and_test(&mem
->refcnt
)) {
1993 mem_cgroup_free(mem
);
1998 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1999 static void __init
enable_swap_cgroup(void)
2001 if (!mem_cgroup_disabled() && really_do_swap_account
)
2002 do_swap_account
= 1;
2005 static void __init
enable_swap_cgroup(void)
2010 static struct cgroup_subsys_state
*
2011 mem_cgroup_create(struct cgroup_subsys
*ss
, struct cgroup
*cont
)
2013 struct mem_cgroup
*mem
, *parent
;
2016 mem
= mem_cgroup_alloc();
2018 return ERR_PTR(-ENOMEM
);
2020 for_each_node_state(node
, N_POSSIBLE
)
2021 if (alloc_mem_cgroup_per_zone_info(mem
, node
))
2024 if (cont
->parent
== NULL
) {
2025 enable_swap_cgroup();
2028 parent
= mem_cgroup_from_cont(cont
->parent
);
2029 mem
->use_hierarchy
= parent
->use_hierarchy
;
2032 if (parent
&& parent
->use_hierarchy
) {
2033 res_counter_init(&mem
->res
, &parent
->res
);
2034 res_counter_init(&mem
->memsw
, &parent
->memsw
);
2036 res_counter_init(&mem
->res
, NULL
);
2037 res_counter_init(&mem
->memsw
, NULL
);
2039 mem_cgroup_set_inactive_ratio(mem
);
2040 mem
->last_scanned_child
= NULL
;
2044 for_each_node_state(node
, N_POSSIBLE
)
2045 free_mem_cgroup_per_zone_info(mem
, node
);
2046 mem_cgroup_free(mem
);
2047 return ERR_PTR(-ENOMEM
);
2050 static void mem_cgroup_pre_destroy(struct cgroup_subsys
*ss
,
2051 struct cgroup
*cont
)
2053 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
2055 mem_cgroup_force_empty(mem
, false);
2058 static void mem_cgroup_destroy(struct cgroup_subsys
*ss
,
2059 struct cgroup
*cont
)
2061 mem_cgroup_free(mem_cgroup_from_cont(cont
));
2064 static int mem_cgroup_populate(struct cgroup_subsys
*ss
,
2065 struct cgroup
*cont
)
2069 ret
= cgroup_add_files(cont
, ss
, mem_cgroup_files
,
2070 ARRAY_SIZE(mem_cgroup_files
));
2073 ret
= register_memsw_files(cont
, ss
);
2077 static void mem_cgroup_move_task(struct cgroup_subsys
*ss
,
2078 struct cgroup
*cont
,
2079 struct cgroup
*old_cont
,
2080 struct task_struct
*p
)
2083 * FIXME: It's better to move charges of this process from old
2084 * memcg to new memcg. But it's just on TODO-List now.
2088 struct cgroup_subsys mem_cgroup_subsys
= {
2090 .subsys_id
= mem_cgroup_subsys_id
,
2091 .create
= mem_cgroup_create
,
2092 .pre_destroy
= mem_cgroup_pre_destroy
,
2093 .destroy
= mem_cgroup_destroy
,
2094 .populate
= mem_cgroup_populate
,
2095 .attach
= mem_cgroup_move_task
,
2099 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2101 static int __init
disable_swap_account(char *s
)
2103 really_do_swap_account
= 0;
2106 __setup("noswapaccount", disable_swap_account
);