1 /* memcontrol.c - Memory Controller
3 * Copyright IBM Corporation, 2007
4 * Author Balbir Singh <balbir@linux.vnet.ibm.com>
6 * Copyright 2007 OpenVZ SWsoft Inc
7 * Author: Pavel Emelianov <xemul@openvz.org>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
20 #include <linux/res_counter.h>
21 #include <linux/memcontrol.h>
22 #include <linux/cgroup.h>
24 #include <linux/pagemap.h>
25 #include <linux/smp.h>
26 #include <linux/page-flags.h>
27 #include <linux/backing-dev.h>
28 #include <linux/bit_spinlock.h>
29 #include <linux/rcupdate.h>
30 #include <linux/mutex.h>
31 #include <linux/slab.h>
32 #include <linux/swap.h>
33 #include <linux/spinlock.h>
35 #include <linux/seq_file.h>
36 #include <linux/vmalloc.h>
37 #include <linux/mm_inline.h>
38 #include <linux/page_cgroup.h>
41 #include <asm/uaccess.h>
43 struct cgroup_subsys mem_cgroup_subsys __read_mostly
;
44 #define MEM_CGROUP_RECLAIM_RETRIES 5
46 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
47 /* Turned on only when memory cgroup is enabled && really_do_swap_account = 0 */
48 int do_swap_account __read_mostly
;
49 static int really_do_swap_account __initdata
= 1; /* for remember boot option*/
51 #define do_swap_account (0)
56 * Statistics for memory cgroup.
58 enum mem_cgroup_stat_index
{
60 * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
62 MEM_CGROUP_STAT_CACHE
, /* # of pages charged as cache */
63 MEM_CGROUP_STAT_RSS
, /* # of pages charged as rss */
64 MEM_CGROUP_STAT_PGPGIN_COUNT
, /* # of pages paged in */
65 MEM_CGROUP_STAT_PGPGOUT_COUNT
, /* # of pages paged out */
67 MEM_CGROUP_STAT_NSTATS
,
70 struct mem_cgroup_stat_cpu
{
71 s64 count
[MEM_CGROUP_STAT_NSTATS
];
72 } ____cacheline_aligned_in_smp
;
74 struct mem_cgroup_stat
{
75 struct mem_cgroup_stat_cpu cpustat
[0];
79 * For accounting under irq disable, no need for increment preempt count.
81 static inline void __mem_cgroup_stat_add_safe(struct mem_cgroup_stat_cpu
*stat
,
82 enum mem_cgroup_stat_index idx
, int val
)
84 stat
->count
[idx
] += val
;
87 static s64
mem_cgroup_read_stat(struct mem_cgroup_stat
*stat
,
88 enum mem_cgroup_stat_index idx
)
92 for_each_possible_cpu(cpu
)
93 ret
+= stat
->cpustat
[cpu
].count
[idx
];
98 * per-zone information in memory controller.
100 struct mem_cgroup_per_zone
{
102 * spin_lock to protect the per cgroup LRU
104 struct list_head lists
[NR_LRU_LISTS
];
105 unsigned long count
[NR_LRU_LISTS
];
107 struct zone_reclaim_stat reclaim_stat
;
109 /* Macro for accessing counter */
110 #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)])
112 struct mem_cgroup_per_node
{
113 struct mem_cgroup_per_zone zoneinfo
[MAX_NR_ZONES
];
116 struct mem_cgroup_lru_info
{
117 struct mem_cgroup_per_node
*nodeinfo
[MAX_NUMNODES
];
121 * The memory controller data structure. The memory controller controls both
122 * page cache and RSS per cgroup. We would eventually like to provide
123 * statistics based on the statistics developed by Rik Van Riel for clock-pro,
124 * to help the administrator determine what knobs to tune.
126 * TODO: Add a water mark for the memory controller. Reclaim will begin when
127 * we hit the water mark. May be even add a low water mark, such that
128 * no reclaim occurs from a cgroup at it's low water mark, this is
129 * a feature that will be implemented much later in the future.
132 struct cgroup_subsys_state css
;
134 * the counter to account for memory usage
136 struct res_counter res
;
138 * the counter to account for mem+swap usage.
140 struct res_counter memsw
;
142 * Per cgroup active and inactive list, similar to the
143 * per zone LRU lists.
145 struct mem_cgroup_lru_info info
;
148 protect against reclaim related member.
150 spinlock_t reclaim_param_lock
;
152 int prev_priority
; /* for recording reclaim priority */
155 * While reclaiming in a hiearchy, we cache the last child we
156 * reclaimed from. Protected by cgroup_lock()
158 struct mem_cgroup
*last_scanned_child
;
160 * Should the accounting and control be hierarchical, per subtree?
163 unsigned long last_oom_jiffies
;
167 unsigned int inactive_ratio
;
170 * statistics. This must be placed at the end of memcg.
172 struct mem_cgroup_stat stat
;
176 MEM_CGROUP_CHARGE_TYPE_CACHE
= 0,
177 MEM_CGROUP_CHARGE_TYPE_MAPPED
,
178 MEM_CGROUP_CHARGE_TYPE_SHMEM
, /* used by page migration of shmem */
179 MEM_CGROUP_CHARGE_TYPE_FORCE
, /* used by force_empty */
180 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
, /* for accounting swapcache */
184 /* only for here (for easy reading.) */
185 #define PCGF_CACHE (1UL << PCG_CACHE)
186 #define PCGF_USED (1UL << PCG_USED)
187 #define PCGF_LOCK (1UL << PCG_LOCK)
188 static const unsigned long
189 pcg_default_flags
[NR_CHARGE_TYPE
] = {
190 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* File Cache */
191 PCGF_USED
| PCGF_LOCK
, /* Anon */
192 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* Shmem */
196 /* for encoding cft->private value on file */
199 #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
200 #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
201 #define MEMFILE_ATTR(val) ((val) & 0xffff)
203 static void mem_cgroup_get(struct mem_cgroup
*mem
);
204 static void mem_cgroup_put(struct mem_cgroup
*mem
);
206 static void mem_cgroup_charge_statistics(struct mem_cgroup
*mem
,
207 struct page_cgroup
*pc
,
210 int val
= (charge
)? 1 : -1;
211 struct mem_cgroup_stat
*stat
= &mem
->stat
;
212 struct mem_cgroup_stat_cpu
*cpustat
;
215 cpustat
= &stat
->cpustat
[cpu
];
216 if (PageCgroupCache(pc
))
217 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_CACHE
, val
);
219 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_RSS
, val
);
222 __mem_cgroup_stat_add_safe(cpustat
,
223 MEM_CGROUP_STAT_PGPGIN_COUNT
, 1);
225 __mem_cgroup_stat_add_safe(cpustat
,
226 MEM_CGROUP_STAT_PGPGOUT_COUNT
, 1);
230 static struct mem_cgroup_per_zone
*
231 mem_cgroup_zoneinfo(struct mem_cgroup
*mem
, int nid
, int zid
)
233 return &mem
->info
.nodeinfo
[nid
]->zoneinfo
[zid
];
236 static struct mem_cgroup_per_zone
*
237 page_cgroup_zoneinfo(struct page_cgroup
*pc
)
239 struct mem_cgroup
*mem
= pc
->mem_cgroup
;
240 int nid
= page_cgroup_nid(pc
);
241 int zid
= page_cgroup_zid(pc
);
246 return mem_cgroup_zoneinfo(mem
, nid
, zid
);
249 static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup
*mem
,
253 struct mem_cgroup_per_zone
*mz
;
256 for_each_online_node(nid
)
257 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
258 mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
259 total
+= MEM_CGROUP_ZSTAT(mz
, idx
);
264 static struct mem_cgroup
*mem_cgroup_from_cont(struct cgroup
*cont
)
266 return container_of(cgroup_subsys_state(cont
,
267 mem_cgroup_subsys_id
), struct mem_cgroup
,
271 struct mem_cgroup
*mem_cgroup_from_task(struct task_struct
*p
)
274 * mm_update_next_owner() may clear mm->owner to NULL
275 * if it races with swapoff, page migration, etc.
276 * So this can be called with p == NULL.
281 return container_of(task_subsys_state(p
, mem_cgroup_subsys_id
),
282 struct mem_cgroup
, css
);
286 * Following LRU functions are allowed to be used without PCG_LOCK.
287 * Operations are called by routine of global LRU independently from memcg.
288 * What we have to take care of here is validness of pc->mem_cgroup.
290 * Changes to pc->mem_cgroup happens when
293 * In typical case, "charge" is done before add-to-lru. Exception is SwapCache.
294 * It is added to LRU before charge.
295 * If PCG_USED bit is not set, page_cgroup is not added to this private LRU.
296 * When moving account, the page is not on LRU. It's isolated.
299 void mem_cgroup_del_lru_list(struct page
*page
, enum lru_list lru
)
301 struct page_cgroup
*pc
;
302 struct mem_cgroup
*mem
;
303 struct mem_cgroup_per_zone
*mz
;
305 if (mem_cgroup_disabled())
307 pc
= lookup_page_cgroup(page
);
308 /* can happen while we handle swapcache. */
309 if (list_empty(&pc
->lru
))
311 mz
= page_cgroup_zoneinfo(pc
);
312 mem
= pc
->mem_cgroup
;
313 MEM_CGROUP_ZSTAT(mz
, lru
) -= 1;
314 list_del_init(&pc
->lru
);
318 void mem_cgroup_del_lru(struct page
*page
)
320 mem_cgroup_del_lru_list(page
, page_lru(page
));
323 void mem_cgroup_rotate_lru_list(struct page
*page
, enum lru_list lru
)
325 struct mem_cgroup_per_zone
*mz
;
326 struct page_cgroup
*pc
;
328 if (mem_cgroup_disabled())
331 pc
= lookup_page_cgroup(page
);
333 /* unused page is not rotated. */
334 if (!PageCgroupUsed(pc
))
336 mz
= page_cgroup_zoneinfo(pc
);
337 list_move(&pc
->lru
, &mz
->lists
[lru
]);
340 void mem_cgroup_add_lru_list(struct page
*page
, enum lru_list lru
)
342 struct page_cgroup
*pc
;
343 struct mem_cgroup_per_zone
*mz
;
345 if (mem_cgroup_disabled())
347 pc
= lookup_page_cgroup(page
);
348 /* barrier to sync with "charge" */
350 if (!PageCgroupUsed(pc
))
353 mz
= page_cgroup_zoneinfo(pc
);
354 MEM_CGROUP_ZSTAT(mz
, lru
) += 1;
355 list_add(&pc
->lru
, &mz
->lists
[lru
]);
358 * To add swapcache into LRU. Be careful to all this function.
359 * zone->lru_lock shouldn't be held and irq must not be disabled.
361 static void mem_cgroup_lru_fixup(struct page
*page
)
363 if (!isolate_lru_page(page
))
364 putback_lru_page(page
);
367 void mem_cgroup_move_lists(struct page
*page
,
368 enum lru_list from
, enum lru_list to
)
370 if (mem_cgroup_disabled())
372 mem_cgroup_del_lru_list(page
, from
);
373 mem_cgroup_add_lru_list(page
, to
);
376 int task_in_mem_cgroup(struct task_struct
*task
, const struct mem_cgroup
*mem
)
381 ret
= task
->mm
&& mm_match_cgroup(task
->mm
, mem
);
387 * Calculate mapped_ratio under memory controller. This will be used in
388 * vmscan.c for deteremining we have to reclaim mapped pages.
390 int mem_cgroup_calc_mapped_ratio(struct mem_cgroup
*mem
)
395 * usage is recorded in bytes. But, here, we assume the number of
396 * physical pages can be represented by "long" on any arch.
398 total
= (long) (mem
->res
.usage
>> PAGE_SHIFT
) + 1L;
399 rss
= (long)mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_RSS
);
400 return (int)((rss
* 100L) / total
);
404 * prev_priority control...this will be used in memory reclaim path.
406 int mem_cgroup_get_reclaim_priority(struct mem_cgroup
*mem
)
410 spin_lock(&mem
->reclaim_param_lock
);
411 prev_priority
= mem
->prev_priority
;
412 spin_unlock(&mem
->reclaim_param_lock
);
414 return prev_priority
;
417 void mem_cgroup_note_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
419 spin_lock(&mem
->reclaim_param_lock
);
420 if (priority
< mem
->prev_priority
)
421 mem
->prev_priority
= priority
;
422 spin_unlock(&mem
->reclaim_param_lock
);
425 void mem_cgroup_record_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
427 spin_lock(&mem
->reclaim_param_lock
);
428 mem
->prev_priority
= priority
;
429 spin_unlock(&mem
->reclaim_param_lock
);
432 int mem_cgroup_inactive_anon_is_low(struct mem_cgroup
*memcg
, struct zone
*zone
)
434 unsigned long active
;
435 unsigned long inactive
;
437 inactive
= mem_cgroup_get_all_zonestat(memcg
, LRU_INACTIVE_ANON
);
438 active
= mem_cgroup_get_all_zonestat(memcg
, LRU_ACTIVE_ANON
);
440 if (inactive
* memcg
->inactive_ratio
< active
)
446 unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup
*memcg
,
450 int nid
= zone
->zone_pgdat
->node_id
;
451 int zid
= zone_idx(zone
);
452 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(memcg
, nid
, zid
);
454 return MEM_CGROUP_ZSTAT(mz
, lru
);
457 struct zone_reclaim_stat
*mem_cgroup_get_reclaim_stat(struct mem_cgroup
*memcg
,
460 int nid
= zone
->zone_pgdat
->node_id
;
461 int zid
= zone_idx(zone
);
462 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(memcg
, nid
, zid
);
464 return &mz
->reclaim_stat
;
467 struct zone_reclaim_stat
*
468 mem_cgroup_get_reclaim_stat_from_page(struct page
*page
)
470 struct page_cgroup
*pc
;
471 struct mem_cgroup_per_zone
*mz
;
473 if (mem_cgroup_disabled())
476 pc
= lookup_page_cgroup(page
);
477 mz
= page_cgroup_zoneinfo(pc
);
481 return &mz
->reclaim_stat
;
484 unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan
,
485 struct list_head
*dst
,
486 unsigned long *scanned
, int order
,
487 int mode
, struct zone
*z
,
488 struct mem_cgroup
*mem_cont
,
489 int active
, int file
)
491 unsigned long nr_taken
= 0;
495 struct list_head
*src
;
496 struct page_cgroup
*pc
, *tmp
;
497 int nid
= z
->zone_pgdat
->node_id
;
498 int zid
= zone_idx(z
);
499 struct mem_cgroup_per_zone
*mz
;
500 int lru
= LRU_FILE
* !!file
+ !!active
;
503 mz
= mem_cgroup_zoneinfo(mem_cont
, nid
, zid
);
504 src
= &mz
->lists
[lru
];
507 list_for_each_entry_safe_reverse(pc
, tmp
, src
, lru
) {
508 if (scan
>= nr_to_scan
)
512 if (unlikely(!PageCgroupUsed(pc
)))
514 if (unlikely(!PageLRU(page
)))
518 if (__isolate_lru_page(page
, mode
, file
) == 0) {
519 list_move(&page
->lru
, dst
);
528 #define mem_cgroup_from_res_counter(counter, member) \
529 container_of(counter, struct mem_cgroup, member)
532 * This routine finds the DFS walk successor. This routine should be
533 * called with cgroup_mutex held
535 static struct mem_cgroup
*
536 mem_cgroup_get_next_node(struct mem_cgroup
*curr
, struct mem_cgroup
*root_mem
)
538 struct cgroup
*cgroup
, *curr_cgroup
, *root_cgroup
;
540 curr_cgroup
= curr
->css
.cgroup
;
541 root_cgroup
= root_mem
->css
.cgroup
;
543 if (!list_empty(&curr_cgroup
->children
)) {
545 * Walk down to children
547 mem_cgroup_put(curr
);
548 cgroup
= list_entry(curr_cgroup
->children
.next
,
549 struct cgroup
, sibling
);
550 curr
= mem_cgroup_from_cont(cgroup
);
551 mem_cgroup_get(curr
);
556 if (curr_cgroup
== root_cgroup
) {
557 mem_cgroup_put(curr
);
559 mem_cgroup_get(curr
);
566 if (curr_cgroup
->sibling
.next
!= &curr_cgroup
->parent
->children
) {
567 mem_cgroup_put(curr
);
568 cgroup
= list_entry(curr_cgroup
->sibling
.next
, struct cgroup
,
570 curr
= mem_cgroup_from_cont(cgroup
);
571 mem_cgroup_get(curr
);
576 * Go up to next parent and next parent's sibling if need be
578 curr_cgroup
= curr_cgroup
->parent
;
582 root_mem
->last_scanned_child
= curr
;
587 * Visit the first child (need not be the first child as per the ordering
588 * of the cgroup list, since we track last_scanned_child) of @mem and use
589 * that to reclaim free pages from.
591 static struct mem_cgroup
*
592 mem_cgroup_get_first_node(struct mem_cgroup
*root_mem
)
594 struct cgroup
*cgroup
;
595 struct mem_cgroup
*ret
;
596 bool obsolete
= (root_mem
->last_scanned_child
&&
597 root_mem
->last_scanned_child
->obsolete
);
600 * Scan all children under the mem_cgroup mem
603 if (list_empty(&root_mem
->css
.cgroup
->children
)) {
608 if (!root_mem
->last_scanned_child
|| obsolete
) {
611 mem_cgroup_put(root_mem
->last_scanned_child
);
613 cgroup
= list_first_entry(&root_mem
->css
.cgroup
->children
,
614 struct cgroup
, sibling
);
615 ret
= mem_cgroup_from_cont(cgroup
);
618 ret
= mem_cgroup_get_next_node(root_mem
->last_scanned_child
,
622 root_mem
->last_scanned_child
= ret
;
627 static bool mem_cgroup_check_under_limit(struct mem_cgroup
*mem
)
629 if (do_swap_account
) {
630 if (res_counter_check_under_limit(&mem
->res
) &&
631 res_counter_check_under_limit(&mem
->memsw
))
634 if (res_counter_check_under_limit(&mem
->res
))
640 * Dance down the hierarchy if needed to reclaim memory. We remember the
641 * last child we reclaimed from, so that we don't end up penalizing
642 * one child extensively based on its position in the children list.
644 * root_mem is the original ancestor that we've been reclaim from.
646 static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup
*root_mem
,
647 gfp_t gfp_mask
, bool noswap
)
649 struct mem_cgroup
*next_mem
;
653 * Reclaim unconditionally and don't check for return value.
654 * We need to reclaim in the current group and down the tree.
655 * One might think about checking for children before reclaiming,
656 * but there might be left over accounting, even after children
659 ret
= try_to_free_mem_cgroup_pages(root_mem
, gfp_mask
, noswap
);
660 if (mem_cgroup_check_under_limit(root_mem
))
662 if (!root_mem
->use_hierarchy
)
665 next_mem
= mem_cgroup_get_first_node(root_mem
);
667 while (next_mem
!= root_mem
) {
668 if (next_mem
->obsolete
) {
669 mem_cgroup_put(next_mem
);
671 next_mem
= mem_cgroup_get_first_node(root_mem
);
675 ret
= try_to_free_mem_cgroup_pages(next_mem
, gfp_mask
, noswap
);
676 if (mem_cgroup_check_under_limit(root_mem
))
679 next_mem
= mem_cgroup_get_next_node(next_mem
, root_mem
);
685 bool mem_cgroup_oom_called(struct task_struct
*task
)
688 struct mem_cgroup
*mem
;
689 struct mm_struct
*mm
;
695 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
696 if (mem
&& time_before(jiffies
, mem
->last_oom_jiffies
+ HZ
/10))
702 * Unlike exported interface, "oom" parameter is added. if oom==true,
703 * oom-killer can be invoked.
705 static int __mem_cgroup_try_charge(struct mm_struct
*mm
,
706 gfp_t gfp_mask
, struct mem_cgroup
**memcg
,
709 struct mem_cgroup
*mem
, *mem_over_limit
;
710 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
711 struct res_counter
*fail_res
;
713 if (unlikely(test_thread_flag(TIF_MEMDIE
))) {
714 /* Don't account this! */
720 * We always charge the cgroup the mm_struct belongs to.
721 * The mm_struct's mem_cgroup changes on task migration if the
722 * thread group leader migrates. It's possible that mm is not
723 * set, if so charge the init_mm (happens for pagecache usage).
725 if (likely(!*memcg
)) {
727 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
728 if (unlikely(!mem
)) {
733 * For every charge from the cgroup, increment reference count
747 ret
= res_counter_charge(&mem
->res
, PAGE_SIZE
, &fail_res
);
749 if (!do_swap_account
)
751 ret
= res_counter_charge(&mem
->memsw
, PAGE_SIZE
,
755 /* mem+swap counter fails */
756 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
758 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
761 /* mem counter fails */
762 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
765 if (!(gfp_mask
& __GFP_WAIT
))
768 ret
= mem_cgroup_hierarchical_reclaim(mem_over_limit
, gfp_mask
,
772 * try_to_free_mem_cgroup_pages() might not give us a full
773 * picture of reclaim. Some pages are reclaimed and might be
774 * moved to swap cache or just unmapped from the cgroup.
775 * Check the limit again to see if the reclaim reduced the
776 * current usage of the cgroup before giving up
779 if (mem_cgroup_check_under_limit(mem_over_limit
))
784 mem_cgroup_out_of_memory(mem_over_limit
, gfp_mask
);
785 mem_over_limit
->last_oom_jiffies
= jiffies
;
797 * mem_cgroup_try_charge - get charge of PAGE_SIZE.
798 * @mm: an mm_struct which is charged against. (when *memcg is NULL)
799 * @gfp_mask: gfp_mask for reclaim.
800 * @memcg: a pointer to memory cgroup which is charged against.
802 * charge against memory cgroup pointed by *memcg. if *memcg == NULL, estimated
803 * memory cgroup from @mm is got and stored in *memcg.
805 * Returns 0 if success. -ENOMEM at failure.
806 * This call can invoke OOM-Killer.
809 int mem_cgroup_try_charge(struct mm_struct
*mm
,
810 gfp_t mask
, struct mem_cgroup
**memcg
)
812 return __mem_cgroup_try_charge(mm
, mask
, memcg
, true);
816 * commit a charge got by mem_cgroup_try_charge() and makes page_cgroup to be
817 * USED state. If already USED, uncharge and return.
820 static void __mem_cgroup_commit_charge(struct mem_cgroup
*mem
,
821 struct page_cgroup
*pc
,
822 enum charge_type ctype
)
824 /* try_charge() can return NULL to *memcg, taking care of it. */
828 lock_page_cgroup(pc
);
829 if (unlikely(PageCgroupUsed(pc
))) {
830 unlock_page_cgroup(pc
);
831 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
833 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
837 pc
->mem_cgroup
= mem
;
839 pc
->flags
= pcg_default_flags
[ctype
];
841 mem_cgroup_charge_statistics(mem
, pc
, true);
843 unlock_page_cgroup(pc
);
847 * mem_cgroup_move_account - move account of the page
848 * @pc: page_cgroup of the page.
849 * @from: mem_cgroup which the page is moved from.
850 * @to: mem_cgroup which the page is moved to. @from != @to.
852 * The caller must confirm following.
853 * - page is not on LRU (isolate_page() is useful.)
855 * returns 0 at success,
856 * returns -EBUSY when lock is busy or "pc" is unstable.
858 * This function does "uncharge" from old cgroup but doesn't do "charge" to
859 * new cgroup. It should be done by a caller.
862 static int mem_cgroup_move_account(struct page_cgroup
*pc
,
863 struct mem_cgroup
*from
, struct mem_cgroup
*to
)
865 struct mem_cgroup_per_zone
*from_mz
, *to_mz
;
869 VM_BUG_ON(from
== to
);
870 VM_BUG_ON(PageLRU(pc
->page
));
872 nid
= page_cgroup_nid(pc
);
873 zid
= page_cgroup_zid(pc
);
874 from_mz
= mem_cgroup_zoneinfo(from
, nid
, zid
);
875 to_mz
= mem_cgroup_zoneinfo(to
, nid
, zid
);
877 if (!trylock_page_cgroup(pc
))
880 if (!PageCgroupUsed(pc
))
883 if (pc
->mem_cgroup
!= from
)
887 res_counter_uncharge(&from
->res
, PAGE_SIZE
);
888 mem_cgroup_charge_statistics(from
, pc
, false);
890 res_counter_uncharge(&from
->memsw
, PAGE_SIZE
);
892 mem_cgroup_charge_statistics(to
, pc
, true);
896 unlock_page_cgroup(pc
);
901 * move charges to its parent.
904 static int mem_cgroup_move_parent(struct page_cgroup
*pc
,
905 struct mem_cgroup
*child
,
908 struct page
*page
= pc
->page
;
909 struct cgroup
*cg
= child
->css
.cgroup
;
910 struct cgroup
*pcg
= cg
->parent
;
911 struct mem_cgroup
*parent
;
919 parent
= mem_cgroup_from_cont(pcg
);
922 ret
= __mem_cgroup_try_charge(NULL
, gfp_mask
, &parent
, false);
926 if (!get_page_unless_zero(page
))
929 ret
= isolate_lru_page(page
);
934 ret
= mem_cgroup_move_account(pc
, child
, parent
);
936 /* drop extra refcnt by try_charge() (move_account increment one) */
937 css_put(&parent
->css
);
938 putback_lru_page(page
);
943 /* uncharge if move fails */
945 res_counter_uncharge(&parent
->res
, PAGE_SIZE
);
947 res_counter_uncharge(&parent
->memsw
, PAGE_SIZE
);
953 * Charge the memory controller for page usage.
955 * 0 if the charge was successful
956 * < 0 if the cgroup is over its limit
958 static int mem_cgroup_charge_common(struct page
*page
, struct mm_struct
*mm
,
959 gfp_t gfp_mask
, enum charge_type ctype
,
960 struct mem_cgroup
*memcg
)
962 struct mem_cgroup
*mem
;
963 struct page_cgroup
*pc
;
966 pc
= lookup_page_cgroup(page
);
967 /* can happen at boot */
973 ret
= __mem_cgroup_try_charge(mm
, gfp_mask
, &mem
, true);
977 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
981 int mem_cgroup_newpage_charge(struct page
*page
,
982 struct mm_struct
*mm
, gfp_t gfp_mask
)
984 if (mem_cgroup_disabled())
986 if (PageCompound(page
))
989 * If already mapped, we don't have to account.
990 * If page cache, page->mapping has address_space.
991 * But page->mapping may have out-of-use anon_vma pointer,
992 * detecit it by PageAnon() check. newly-mapped-anon's page->mapping
995 if (page_mapped(page
) || (page
->mapping
&& !PageAnon(page
)))
999 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1000 MEM_CGROUP_CHARGE_TYPE_MAPPED
, NULL
);
1003 int mem_cgroup_cache_charge(struct page
*page
, struct mm_struct
*mm
,
1006 if (mem_cgroup_disabled())
1008 if (PageCompound(page
))
1011 * Corner case handling. This is called from add_to_page_cache()
1012 * in usual. But some FS (shmem) precharges this page before calling it
1013 * and call add_to_page_cache() with GFP_NOWAIT.
1015 * For GFP_NOWAIT case, the page may be pre-charged before calling
1016 * add_to_page_cache(). (See shmem.c) check it here and avoid to call
1017 * charge twice. (It works but has to pay a bit larger cost.)
1019 if (!(gfp_mask
& __GFP_WAIT
)) {
1020 struct page_cgroup
*pc
;
1023 pc
= lookup_page_cgroup(page
);
1026 lock_page_cgroup(pc
);
1027 if (PageCgroupUsed(pc
)) {
1028 unlock_page_cgroup(pc
);
1031 unlock_page_cgroup(pc
);
1037 if (page_is_file_cache(page
))
1038 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1039 MEM_CGROUP_CHARGE_TYPE_CACHE
, NULL
);
1041 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1042 MEM_CGROUP_CHARGE_TYPE_SHMEM
, NULL
);
1045 int mem_cgroup_try_charge_swapin(struct mm_struct
*mm
,
1047 gfp_t mask
, struct mem_cgroup
**ptr
)
1049 struct mem_cgroup
*mem
;
1052 if (mem_cgroup_disabled())
1055 if (!do_swap_account
)
1059 * A racing thread's fault, or swapoff, may have already updated
1060 * the pte, and even removed page from swap cache: return success
1061 * to go on to do_swap_page()'s pte_same() test, which should fail.
1063 if (!PageSwapCache(page
))
1066 ent
.val
= page_private(page
);
1068 mem
= lookup_swap_cgroup(ent
);
1069 if (!mem
|| mem
->obsolete
)
1072 return __mem_cgroup_try_charge(NULL
, mask
, ptr
, true);
1076 return __mem_cgroup_try_charge(mm
, mask
, ptr
, true);
1081 int mem_cgroup_cache_charge_swapin(struct page
*page
,
1082 struct mm_struct
*mm
, gfp_t mask
, bool locked
)
1086 if (mem_cgroup_disabled())
1093 * If not locked, the page can be dropped from SwapCache until
1096 if (PageSwapCache(page
)) {
1097 struct mem_cgroup
*mem
= NULL
;
1100 ent
.val
= page_private(page
);
1101 if (do_swap_account
) {
1102 mem
= lookup_swap_cgroup(ent
);
1103 if (mem
&& mem
->obsolete
)
1108 ret
= mem_cgroup_charge_common(page
, mm
, mask
,
1109 MEM_CGROUP_CHARGE_TYPE_SHMEM
, mem
);
1111 if (!ret
&& do_swap_account
) {
1112 /* avoid double counting */
1113 mem
= swap_cgroup_record(ent
, NULL
);
1115 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1116 mem_cgroup_put(mem
);
1122 /* add this page(page_cgroup) to the LRU we want. */
1123 mem_cgroup_lru_fixup(page
);
1129 void mem_cgroup_commit_charge_swapin(struct page
*page
, struct mem_cgroup
*ptr
)
1131 struct page_cgroup
*pc
;
1133 if (mem_cgroup_disabled())
1137 pc
= lookup_page_cgroup(page
);
1138 __mem_cgroup_commit_charge(ptr
, pc
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1140 * Now swap is on-memory. This means this page may be
1141 * counted both as mem and swap....double count.
1142 * Fix it by uncharging from memsw. This SwapCache is stable
1143 * because we're still under lock_page().
1145 if (do_swap_account
) {
1146 swp_entry_t ent
= {.val
= page_private(page
)};
1147 struct mem_cgroup
*memcg
;
1148 memcg
= swap_cgroup_record(ent
, NULL
);
1150 /* If memcg is obsolete, memcg can be != ptr */
1151 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1152 mem_cgroup_put(memcg
);
1156 /* add this page(page_cgroup) to the LRU we want. */
1157 mem_cgroup_lru_fixup(page
);
1160 void mem_cgroup_cancel_charge_swapin(struct mem_cgroup
*mem
)
1162 if (mem_cgroup_disabled())
1166 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1167 if (do_swap_account
)
1168 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1174 * uncharge if !page_mapped(page)
1176 static struct mem_cgroup
*
1177 __mem_cgroup_uncharge_common(struct page
*page
, enum charge_type ctype
)
1179 struct page_cgroup
*pc
;
1180 struct mem_cgroup
*mem
= NULL
;
1181 struct mem_cgroup_per_zone
*mz
;
1183 if (mem_cgroup_disabled())
1186 if (PageSwapCache(page
))
1190 * Check if our page_cgroup is valid
1192 pc
= lookup_page_cgroup(page
);
1193 if (unlikely(!pc
|| !PageCgroupUsed(pc
)))
1196 lock_page_cgroup(pc
);
1198 mem
= pc
->mem_cgroup
;
1200 if (!PageCgroupUsed(pc
))
1204 case MEM_CGROUP_CHARGE_TYPE_MAPPED
:
1205 if (page_mapped(page
))
1208 case MEM_CGROUP_CHARGE_TYPE_SWAPOUT
:
1209 if (!PageAnon(page
)) { /* Shared memory */
1210 if (page
->mapping
&& !page_is_file_cache(page
))
1212 } else if (page_mapped(page
)) /* Anon */
1219 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1220 if (do_swap_account
&& (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
))
1221 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1223 mem_cgroup_charge_statistics(mem
, pc
, false);
1224 ClearPageCgroupUsed(pc
);
1226 mz
= page_cgroup_zoneinfo(pc
);
1227 unlock_page_cgroup(pc
);
1229 /* at swapout, this memcg will be accessed to record to swap */
1230 if (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
)
1236 unlock_page_cgroup(pc
);
1240 void mem_cgroup_uncharge_page(struct page
*page
)
1243 if (page_mapped(page
))
1245 if (page
->mapping
&& !PageAnon(page
))
1247 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1250 void mem_cgroup_uncharge_cache_page(struct page
*page
)
1252 VM_BUG_ON(page_mapped(page
));
1253 VM_BUG_ON(page
->mapping
);
1254 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_CACHE
);
1258 * called from __delete_from_swap_cache() and drop "page" account.
1259 * memcg information is recorded to swap_cgroup of "ent"
1261 void mem_cgroup_uncharge_swapcache(struct page
*page
, swp_entry_t ent
)
1263 struct mem_cgroup
*memcg
;
1265 memcg
= __mem_cgroup_uncharge_common(page
,
1266 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
);
1267 /* record memcg information */
1268 if (do_swap_account
&& memcg
) {
1269 swap_cgroup_record(ent
, memcg
);
1270 mem_cgroup_get(memcg
);
1273 css_put(&memcg
->css
);
1276 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1278 * called from swap_entry_free(). remove record in swap_cgroup and
1279 * uncharge "memsw" account.
1281 void mem_cgroup_uncharge_swap(swp_entry_t ent
)
1283 struct mem_cgroup
*memcg
;
1285 if (!do_swap_account
)
1288 memcg
= swap_cgroup_record(ent
, NULL
);
1290 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1291 mem_cgroup_put(memcg
);
1297 * Before starting migration, account PAGE_SIZE to mem_cgroup that the old
1300 int mem_cgroup_prepare_migration(struct page
*page
, struct mem_cgroup
**ptr
)
1302 struct page_cgroup
*pc
;
1303 struct mem_cgroup
*mem
= NULL
;
1306 if (mem_cgroup_disabled())
1309 pc
= lookup_page_cgroup(page
);
1310 lock_page_cgroup(pc
);
1311 if (PageCgroupUsed(pc
)) {
1312 mem
= pc
->mem_cgroup
;
1315 unlock_page_cgroup(pc
);
1318 ret
= mem_cgroup_try_charge(NULL
, GFP_KERNEL
, &mem
);
1325 /* remove redundant charge if migration failed*/
1326 void mem_cgroup_end_migration(struct mem_cgroup
*mem
,
1327 struct page
*oldpage
, struct page
*newpage
)
1329 struct page
*target
, *unused
;
1330 struct page_cgroup
*pc
;
1331 enum charge_type ctype
;
1336 /* at migration success, oldpage->mapping is NULL. */
1337 if (oldpage
->mapping
) {
1345 if (PageAnon(target
))
1346 ctype
= MEM_CGROUP_CHARGE_TYPE_MAPPED
;
1347 else if (page_is_file_cache(target
))
1348 ctype
= MEM_CGROUP_CHARGE_TYPE_CACHE
;
1350 ctype
= MEM_CGROUP_CHARGE_TYPE_SHMEM
;
1352 /* unused page is not on radix-tree now. */
1354 __mem_cgroup_uncharge_common(unused
, ctype
);
1356 pc
= lookup_page_cgroup(target
);
1358 * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
1359 * So, double-counting is effectively avoided.
1361 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
1364 * Both of oldpage and newpage are still under lock_page().
1365 * Then, we don't have to care about race in radix-tree.
1366 * But we have to be careful that this page is unmapped or not.
1368 * There is a case for !page_mapped(). At the start of
1369 * migration, oldpage was mapped. But now, it's zapped.
1370 * But we know *target* page is not freed/reused under us.
1371 * mem_cgroup_uncharge_page() does all necessary checks.
1373 if (ctype
== MEM_CGROUP_CHARGE_TYPE_MAPPED
)
1374 mem_cgroup_uncharge_page(target
);
1378 * A call to try to shrink memory usage under specified resource controller.
1379 * This is typically used for page reclaiming for shmem for reducing side
1380 * effect of page allocation from shmem, which is used by some mem_cgroup.
1382 int mem_cgroup_shrink_usage(struct mm_struct
*mm
, gfp_t gfp_mask
)
1384 struct mem_cgroup
*mem
;
1386 int retry
= MEM_CGROUP_RECLAIM_RETRIES
;
1388 if (mem_cgroup_disabled())
1394 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
1395 if (unlikely(!mem
)) {
1403 progress
= try_to_free_mem_cgroup_pages(mem
, gfp_mask
, true);
1404 progress
+= mem_cgroup_check_under_limit(mem
);
1405 } while (!progress
&& --retry
);
1414 * The inactive anon list should be small enough that the VM never has to
1415 * do too much work, but large enough that each inactive page has a chance
1416 * to be referenced again before it is swapped out.
1418 * this calculation is straightforward porting from
1419 * page_alloc.c::setup_per_zone_inactive_ratio().
1420 * it describe more detail.
1422 static void mem_cgroup_set_inactive_ratio(struct mem_cgroup
*memcg
)
1424 unsigned int gb
, ratio
;
1426 gb
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
) >> 30;
1428 ratio
= int_sqrt(10 * gb
);
1432 memcg
->inactive_ratio
= ratio
;
1436 static DEFINE_MUTEX(set_limit_mutex
);
1438 static int mem_cgroup_resize_limit(struct mem_cgroup
*memcg
,
1439 unsigned long long val
)
1442 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1447 while (retry_count
) {
1448 if (signal_pending(current
)) {
1453 * Rather than hide all in some function, I do this in
1454 * open coded manner. You see what this really does.
1455 * We have to guarantee mem->res.limit < mem->memsw.limit.
1457 mutex_lock(&set_limit_mutex
);
1458 memswlimit
= res_counter_read_u64(&memcg
->memsw
, RES_LIMIT
);
1459 if (memswlimit
< val
) {
1461 mutex_unlock(&set_limit_mutex
);
1464 ret
= res_counter_set_limit(&memcg
->res
, val
);
1465 mutex_unlock(&set_limit_mutex
);
1470 progress
= try_to_free_mem_cgroup_pages(memcg
,
1472 if (!progress
) retry_count
--;
1476 mem_cgroup_set_inactive_ratio(memcg
);
1481 int mem_cgroup_resize_memsw_limit(struct mem_cgroup
*memcg
,
1482 unsigned long long val
)
1484 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1485 u64 memlimit
, oldusage
, curusage
;
1488 if (!do_swap_account
)
1491 while (retry_count
) {
1492 if (signal_pending(current
)) {
1497 * Rather than hide all in some function, I do this in
1498 * open coded manner. You see what this really does.
1499 * We have to guarantee mem->res.limit < mem->memsw.limit.
1501 mutex_lock(&set_limit_mutex
);
1502 memlimit
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
);
1503 if (memlimit
> val
) {
1505 mutex_unlock(&set_limit_mutex
);
1508 ret
= res_counter_set_limit(&memcg
->memsw
, val
);
1509 mutex_unlock(&set_limit_mutex
);
1514 oldusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1515 try_to_free_mem_cgroup_pages(memcg
, GFP_KERNEL
, true);
1516 curusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1517 if (curusage
>= oldusage
)
1524 * This routine traverse page_cgroup in given list and drop them all.
1525 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
1527 static int mem_cgroup_force_empty_list(struct mem_cgroup
*mem
,
1528 int node
, int zid
, enum lru_list lru
)
1531 struct mem_cgroup_per_zone
*mz
;
1532 struct page_cgroup
*pc
, *busy
;
1533 unsigned long flags
, loop
;
1534 struct list_head
*list
;
1537 zone
= &NODE_DATA(node
)->node_zones
[zid
];
1538 mz
= mem_cgroup_zoneinfo(mem
, node
, zid
);
1539 list
= &mz
->lists
[lru
];
1541 loop
= MEM_CGROUP_ZSTAT(mz
, lru
);
1542 /* give some margin against EBUSY etc...*/
1547 spin_lock_irqsave(&zone
->lru_lock
, flags
);
1548 if (list_empty(list
)) {
1549 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1552 pc
= list_entry(list
->prev
, struct page_cgroup
, lru
);
1554 list_move(&pc
->lru
, list
);
1556 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1559 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1561 ret
= mem_cgroup_move_parent(pc
, mem
, GFP_KERNEL
);
1565 if (ret
== -EBUSY
|| ret
== -EINVAL
) {
1566 /* found lock contention or "pc" is obsolete. */
1573 if (!ret
&& !list_empty(list
))
1579 * make mem_cgroup's charge to be 0 if there is no task.
1580 * This enables deleting this mem_cgroup.
1582 static int mem_cgroup_force_empty(struct mem_cgroup
*mem
, bool free_all
)
1585 int node
, zid
, shrink
;
1586 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
1587 struct cgroup
*cgrp
= mem
->css
.cgroup
;
1592 /* should free all ? */
1596 while (mem
->res
.usage
> 0) {
1598 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
))
1601 if (signal_pending(current
))
1603 /* This is for making all *used* pages to be on LRU. */
1604 lru_add_drain_all();
1606 for_each_node_state(node
, N_POSSIBLE
) {
1607 for (zid
= 0; !ret
&& zid
< MAX_NR_ZONES
; zid
++) {
1610 ret
= mem_cgroup_force_empty_list(mem
,
1619 /* it seems parent cgroup doesn't have enough mem */
1630 /* returns EBUSY if there is a task or if we come here twice. */
1631 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
) || shrink
) {
1635 /* we call try-to-free pages for make this cgroup empty */
1636 lru_add_drain_all();
1637 /* try to free all pages in this cgroup */
1639 while (nr_retries
&& mem
->res
.usage
> 0) {
1642 if (signal_pending(current
)) {
1646 progress
= try_to_free_mem_cgroup_pages(mem
,
1650 /* maybe some writeback is necessary */
1651 congestion_wait(WRITE
, HZ
/10);
1656 /* try move_account...there may be some *locked* pages. */
1663 int mem_cgroup_force_empty_write(struct cgroup
*cont
, unsigned int event
)
1665 return mem_cgroup_force_empty(mem_cgroup_from_cont(cont
), true);
1669 static u64
mem_cgroup_hierarchy_read(struct cgroup
*cont
, struct cftype
*cft
)
1671 return mem_cgroup_from_cont(cont
)->use_hierarchy
;
1674 static int mem_cgroup_hierarchy_write(struct cgroup
*cont
, struct cftype
*cft
,
1678 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1679 struct cgroup
*parent
= cont
->parent
;
1680 struct mem_cgroup
*parent_mem
= NULL
;
1683 parent_mem
= mem_cgroup_from_cont(parent
);
1687 * If parent's use_hiearchy is set, we can't make any modifications
1688 * in the child subtrees. If it is unset, then the change can
1689 * occur, provided the current cgroup has no children.
1691 * For the root cgroup, parent_mem is NULL, we allow value to be
1692 * set if there are no children.
1694 if ((!parent_mem
|| !parent_mem
->use_hierarchy
) &&
1695 (val
== 1 || val
== 0)) {
1696 if (list_empty(&cont
->children
))
1697 mem
->use_hierarchy
= val
;
1707 static u64
mem_cgroup_read(struct cgroup
*cont
, struct cftype
*cft
)
1709 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1713 type
= MEMFILE_TYPE(cft
->private);
1714 name
= MEMFILE_ATTR(cft
->private);
1717 val
= res_counter_read_u64(&mem
->res
, name
);
1720 if (do_swap_account
)
1721 val
= res_counter_read_u64(&mem
->memsw
, name
);
1730 * The user of this function is...
1733 static int mem_cgroup_write(struct cgroup
*cont
, struct cftype
*cft
,
1736 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cont
);
1738 unsigned long long val
;
1741 type
= MEMFILE_TYPE(cft
->private);
1742 name
= MEMFILE_ATTR(cft
->private);
1745 /* This function does all necessary parse...reuse it */
1746 ret
= res_counter_memparse_write_strategy(buffer
, &val
);
1750 ret
= mem_cgroup_resize_limit(memcg
, val
);
1752 ret
= mem_cgroup_resize_memsw_limit(memcg
, val
);
1755 ret
= -EINVAL
; /* should be BUG() ? */
1761 static int mem_cgroup_reset(struct cgroup
*cont
, unsigned int event
)
1763 struct mem_cgroup
*mem
;
1766 mem
= mem_cgroup_from_cont(cont
);
1767 type
= MEMFILE_TYPE(event
);
1768 name
= MEMFILE_ATTR(event
);
1772 res_counter_reset_max(&mem
->res
);
1774 res_counter_reset_max(&mem
->memsw
);
1778 res_counter_reset_failcnt(&mem
->res
);
1780 res_counter_reset_failcnt(&mem
->memsw
);
1786 static const struct mem_cgroup_stat_desc
{
1789 } mem_cgroup_stat_desc
[] = {
1790 [MEM_CGROUP_STAT_CACHE
] = { "cache", PAGE_SIZE
, },
1791 [MEM_CGROUP_STAT_RSS
] = { "rss", PAGE_SIZE
, },
1792 [MEM_CGROUP_STAT_PGPGIN_COUNT
] = {"pgpgin", 1, },
1793 [MEM_CGROUP_STAT_PGPGOUT_COUNT
] = {"pgpgout", 1, },
1796 static int mem_control_stat_show(struct cgroup
*cont
, struct cftype
*cft
,
1797 struct cgroup_map_cb
*cb
)
1799 struct mem_cgroup
*mem_cont
= mem_cgroup_from_cont(cont
);
1800 struct mem_cgroup_stat
*stat
= &mem_cont
->stat
;
1803 for (i
= 0; i
< ARRAY_SIZE(stat
->cpustat
[0].count
); i
++) {
1806 val
= mem_cgroup_read_stat(stat
, i
);
1807 val
*= mem_cgroup_stat_desc
[i
].unit
;
1808 cb
->fill(cb
, mem_cgroup_stat_desc
[i
].msg
, val
);
1810 /* showing # of active pages */
1812 unsigned long active_anon
, inactive_anon
;
1813 unsigned long active_file
, inactive_file
;
1814 unsigned long unevictable
;
1816 inactive_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1818 active_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1820 inactive_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1822 active_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1824 unevictable
= mem_cgroup_get_all_zonestat(mem_cont
,
1827 cb
->fill(cb
, "active_anon", (active_anon
) * PAGE_SIZE
);
1828 cb
->fill(cb
, "inactive_anon", (inactive_anon
) * PAGE_SIZE
);
1829 cb
->fill(cb
, "active_file", (active_file
) * PAGE_SIZE
);
1830 cb
->fill(cb
, "inactive_file", (inactive_file
) * PAGE_SIZE
);
1831 cb
->fill(cb
, "unevictable", unevictable
* PAGE_SIZE
);
1835 #ifdef CONFIG_DEBUG_VM
1836 cb
->fill(cb
, "inactive_ratio", mem_cont
->inactive_ratio
);
1840 struct mem_cgroup_per_zone
*mz
;
1841 unsigned long recent_rotated
[2] = {0, 0};
1842 unsigned long recent_scanned
[2] = {0, 0};
1844 for_each_online_node(nid
)
1845 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
1846 mz
= mem_cgroup_zoneinfo(mem_cont
, nid
, zid
);
1848 recent_rotated
[0] +=
1849 mz
->reclaim_stat
.recent_rotated
[0];
1850 recent_rotated
[1] +=
1851 mz
->reclaim_stat
.recent_rotated
[1];
1852 recent_scanned
[0] +=
1853 mz
->reclaim_stat
.recent_scanned
[0];
1854 recent_scanned
[1] +=
1855 mz
->reclaim_stat
.recent_scanned
[1];
1857 cb
->fill(cb
, "recent_rotated_anon", recent_rotated
[0]);
1858 cb
->fill(cb
, "recent_rotated_file", recent_rotated
[1]);
1859 cb
->fill(cb
, "recent_scanned_anon", recent_scanned
[0]);
1860 cb
->fill(cb
, "recent_scanned_file", recent_scanned
[1]);
1868 static struct cftype mem_cgroup_files
[] = {
1870 .name
= "usage_in_bytes",
1871 .private = MEMFILE_PRIVATE(_MEM
, RES_USAGE
),
1872 .read_u64
= mem_cgroup_read
,
1875 .name
= "max_usage_in_bytes",
1876 .private = MEMFILE_PRIVATE(_MEM
, RES_MAX_USAGE
),
1877 .trigger
= mem_cgroup_reset
,
1878 .read_u64
= mem_cgroup_read
,
1881 .name
= "limit_in_bytes",
1882 .private = MEMFILE_PRIVATE(_MEM
, RES_LIMIT
),
1883 .write_string
= mem_cgroup_write
,
1884 .read_u64
= mem_cgroup_read
,
1888 .private = MEMFILE_PRIVATE(_MEM
, RES_FAILCNT
),
1889 .trigger
= mem_cgroup_reset
,
1890 .read_u64
= mem_cgroup_read
,
1894 .read_map
= mem_control_stat_show
,
1897 .name
= "force_empty",
1898 .trigger
= mem_cgroup_force_empty_write
,
1901 .name
= "use_hierarchy",
1902 .write_u64
= mem_cgroup_hierarchy_write
,
1903 .read_u64
= mem_cgroup_hierarchy_read
,
1907 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1908 static struct cftype memsw_cgroup_files
[] = {
1910 .name
= "memsw.usage_in_bytes",
1911 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_USAGE
),
1912 .read_u64
= mem_cgroup_read
,
1915 .name
= "memsw.max_usage_in_bytes",
1916 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_MAX_USAGE
),
1917 .trigger
= mem_cgroup_reset
,
1918 .read_u64
= mem_cgroup_read
,
1921 .name
= "memsw.limit_in_bytes",
1922 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_LIMIT
),
1923 .write_string
= mem_cgroup_write
,
1924 .read_u64
= mem_cgroup_read
,
1927 .name
= "memsw.failcnt",
1928 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_FAILCNT
),
1929 .trigger
= mem_cgroup_reset
,
1930 .read_u64
= mem_cgroup_read
,
1934 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1936 if (!do_swap_account
)
1938 return cgroup_add_files(cont
, ss
, memsw_cgroup_files
,
1939 ARRAY_SIZE(memsw_cgroup_files
));
1942 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1948 static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
1950 struct mem_cgroup_per_node
*pn
;
1951 struct mem_cgroup_per_zone
*mz
;
1953 int zone
, tmp
= node
;
1955 * This routine is called against possible nodes.
1956 * But it's BUG to call kmalloc() against offline node.
1958 * TODO: this routine can waste much memory for nodes which will
1959 * never be onlined. It's better to use memory hotplug callback
1962 if (!node_state(node
, N_NORMAL_MEMORY
))
1964 pn
= kmalloc_node(sizeof(*pn
), GFP_KERNEL
, tmp
);
1968 mem
->info
.nodeinfo
[node
] = pn
;
1969 memset(pn
, 0, sizeof(*pn
));
1971 for (zone
= 0; zone
< MAX_NR_ZONES
; zone
++) {
1972 mz
= &pn
->zoneinfo
[zone
];
1974 INIT_LIST_HEAD(&mz
->lists
[l
]);
1979 static void free_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
1981 kfree(mem
->info
.nodeinfo
[node
]);
1984 static int mem_cgroup_size(void)
1986 int cpustat_size
= nr_cpu_ids
* sizeof(struct mem_cgroup_stat_cpu
);
1987 return sizeof(struct mem_cgroup
) + cpustat_size
;
1990 static struct mem_cgroup
*mem_cgroup_alloc(void)
1992 struct mem_cgroup
*mem
;
1993 int size
= mem_cgroup_size();
1995 if (size
< PAGE_SIZE
)
1996 mem
= kmalloc(size
, GFP_KERNEL
);
1998 mem
= vmalloc(size
);
2001 memset(mem
, 0, size
);
2006 * At destroying mem_cgroup, references from swap_cgroup can remain.
2007 * (scanning all at force_empty is too costly...)
2009 * Instead of clearing all references at force_empty, we remember
2010 * the number of reference from swap_cgroup and free mem_cgroup when
2011 * it goes down to 0.
2013 * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and
2014 * entry which points to this memcg will be ignore at swapin.
2016 * Removal of cgroup itself succeeds regardless of refs from swap.
2019 static void mem_cgroup_free(struct mem_cgroup
*mem
)
2023 if (atomic_read(&mem
->refcnt
) > 0)
2027 for_each_node_state(node
, N_POSSIBLE
)
2028 free_mem_cgroup_per_zone_info(mem
, node
);
2030 if (mem_cgroup_size() < PAGE_SIZE
)
2036 static void mem_cgroup_get(struct mem_cgroup
*mem
)
2038 atomic_inc(&mem
->refcnt
);
2041 static void mem_cgroup_put(struct mem_cgroup
*mem
)
2043 if (atomic_dec_and_test(&mem
->refcnt
)) {
2046 mem_cgroup_free(mem
);
2051 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2052 static void __init
enable_swap_cgroup(void)
2054 if (!mem_cgroup_disabled() && really_do_swap_account
)
2055 do_swap_account
= 1;
2058 static void __init
enable_swap_cgroup(void)
2063 static struct cgroup_subsys_state
*
2064 mem_cgroup_create(struct cgroup_subsys
*ss
, struct cgroup
*cont
)
2066 struct mem_cgroup
*mem
, *parent
;
2069 mem
= mem_cgroup_alloc();
2071 return ERR_PTR(-ENOMEM
);
2073 for_each_node_state(node
, N_POSSIBLE
)
2074 if (alloc_mem_cgroup_per_zone_info(mem
, node
))
2077 if (cont
->parent
== NULL
) {
2078 enable_swap_cgroup();
2081 parent
= mem_cgroup_from_cont(cont
->parent
);
2082 mem
->use_hierarchy
= parent
->use_hierarchy
;
2085 if (parent
&& parent
->use_hierarchy
) {
2086 res_counter_init(&mem
->res
, &parent
->res
);
2087 res_counter_init(&mem
->memsw
, &parent
->memsw
);
2089 res_counter_init(&mem
->res
, NULL
);
2090 res_counter_init(&mem
->memsw
, NULL
);
2092 mem_cgroup_set_inactive_ratio(mem
);
2093 mem
->last_scanned_child
= NULL
;
2094 spin_lock_init(&mem
->reclaim_param_lock
);
2098 for_each_node_state(node
, N_POSSIBLE
)
2099 free_mem_cgroup_per_zone_info(mem
, node
);
2100 mem_cgroup_free(mem
);
2101 return ERR_PTR(-ENOMEM
);
2104 static void mem_cgroup_pre_destroy(struct cgroup_subsys
*ss
,
2105 struct cgroup
*cont
)
2107 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
2109 mem_cgroup_force_empty(mem
, false);
2112 static void mem_cgroup_destroy(struct cgroup_subsys
*ss
,
2113 struct cgroup
*cont
)
2115 mem_cgroup_free(mem_cgroup_from_cont(cont
));
2118 static int mem_cgroup_populate(struct cgroup_subsys
*ss
,
2119 struct cgroup
*cont
)
2123 ret
= cgroup_add_files(cont
, ss
, mem_cgroup_files
,
2124 ARRAY_SIZE(mem_cgroup_files
));
2127 ret
= register_memsw_files(cont
, ss
);
2131 static void mem_cgroup_move_task(struct cgroup_subsys
*ss
,
2132 struct cgroup
*cont
,
2133 struct cgroup
*old_cont
,
2134 struct task_struct
*p
)
2137 * FIXME: It's better to move charges of this process from old
2138 * memcg to new memcg. But it's just on TODO-List now.
2142 struct cgroup_subsys mem_cgroup_subsys
= {
2144 .subsys_id
= mem_cgroup_subsys_id
,
2145 .create
= mem_cgroup_create
,
2146 .pre_destroy
= mem_cgroup_pre_destroy
,
2147 .destroy
= mem_cgroup_destroy
,
2148 .populate
= mem_cgroup_populate
,
2149 .attach
= mem_cgroup_move_task
,
2153 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2155 static int __init
disable_swap_account(char *s
)
2157 really_do_swap_account
= 0;
2160 __setup("noswapaccount", disable_swap_account
);