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 swappiness
;
170 unsigned int inactive_ratio
;
173 * statistics. This must be placed at the end of memcg.
175 struct mem_cgroup_stat stat
;
179 MEM_CGROUP_CHARGE_TYPE_CACHE
= 0,
180 MEM_CGROUP_CHARGE_TYPE_MAPPED
,
181 MEM_CGROUP_CHARGE_TYPE_SHMEM
, /* used by page migration of shmem */
182 MEM_CGROUP_CHARGE_TYPE_FORCE
, /* used by force_empty */
183 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
, /* for accounting swapcache */
187 /* only for here (for easy reading.) */
188 #define PCGF_CACHE (1UL << PCG_CACHE)
189 #define PCGF_USED (1UL << PCG_USED)
190 #define PCGF_LOCK (1UL << PCG_LOCK)
191 static const unsigned long
192 pcg_default_flags
[NR_CHARGE_TYPE
] = {
193 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* File Cache */
194 PCGF_USED
| PCGF_LOCK
, /* Anon */
195 PCGF_CACHE
| PCGF_USED
| PCGF_LOCK
, /* Shmem */
199 /* for encoding cft->private value on file */
202 #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
203 #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
204 #define MEMFILE_ATTR(val) ((val) & 0xffff)
206 static void mem_cgroup_get(struct mem_cgroup
*mem
);
207 static void mem_cgroup_put(struct mem_cgroup
*mem
);
209 static void mem_cgroup_charge_statistics(struct mem_cgroup
*mem
,
210 struct page_cgroup
*pc
,
213 int val
= (charge
)? 1 : -1;
214 struct mem_cgroup_stat
*stat
= &mem
->stat
;
215 struct mem_cgroup_stat_cpu
*cpustat
;
218 cpustat
= &stat
->cpustat
[cpu
];
219 if (PageCgroupCache(pc
))
220 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_CACHE
, val
);
222 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_RSS
, val
);
225 __mem_cgroup_stat_add_safe(cpustat
,
226 MEM_CGROUP_STAT_PGPGIN_COUNT
, 1);
228 __mem_cgroup_stat_add_safe(cpustat
,
229 MEM_CGROUP_STAT_PGPGOUT_COUNT
, 1);
233 static struct mem_cgroup_per_zone
*
234 mem_cgroup_zoneinfo(struct mem_cgroup
*mem
, int nid
, int zid
)
236 return &mem
->info
.nodeinfo
[nid
]->zoneinfo
[zid
];
239 static struct mem_cgroup_per_zone
*
240 page_cgroup_zoneinfo(struct page_cgroup
*pc
)
242 struct mem_cgroup
*mem
= pc
->mem_cgroup
;
243 int nid
= page_cgroup_nid(pc
);
244 int zid
= page_cgroup_zid(pc
);
249 return mem_cgroup_zoneinfo(mem
, nid
, zid
);
252 static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup
*mem
,
256 struct mem_cgroup_per_zone
*mz
;
259 for_each_online_node(nid
)
260 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
261 mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
262 total
+= MEM_CGROUP_ZSTAT(mz
, idx
);
267 static struct mem_cgroup
*mem_cgroup_from_cont(struct cgroup
*cont
)
269 return container_of(cgroup_subsys_state(cont
,
270 mem_cgroup_subsys_id
), struct mem_cgroup
,
274 struct mem_cgroup
*mem_cgroup_from_task(struct task_struct
*p
)
277 * mm_update_next_owner() may clear mm->owner to NULL
278 * if it races with swapoff, page migration, etc.
279 * So this can be called with p == NULL.
284 return container_of(task_subsys_state(p
, mem_cgroup_subsys_id
),
285 struct mem_cgroup
, css
);
289 * Following LRU functions are allowed to be used without PCG_LOCK.
290 * Operations are called by routine of global LRU independently from memcg.
291 * What we have to take care of here is validness of pc->mem_cgroup.
293 * Changes to pc->mem_cgroup happens when
296 * In typical case, "charge" is done before add-to-lru. Exception is SwapCache.
297 * It is added to LRU before charge.
298 * If PCG_USED bit is not set, page_cgroup is not added to this private LRU.
299 * When moving account, the page is not on LRU. It's isolated.
302 void mem_cgroup_del_lru_list(struct page
*page
, enum lru_list lru
)
304 struct page_cgroup
*pc
;
305 struct mem_cgroup
*mem
;
306 struct mem_cgroup_per_zone
*mz
;
308 if (mem_cgroup_disabled())
310 pc
= lookup_page_cgroup(page
);
311 /* can happen while we handle swapcache. */
312 if (list_empty(&pc
->lru
))
314 mz
= page_cgroup_zoneinfo(pc
);
315 mem
= pc
->mem_cgroup
;
316 MEM_CGROUP_ZSTAT(mz
, lru
) -= 1;
317 list_del_init(&pc
->lru
);
321 void mem_cgroup_del_lru(struct page
*page
)
323 mem_cgroup_del_lru_list(page
, page_lru(page
));
326 void mem_cgroup_rotate_lru_list(struct page
*page
, enum lru_list lru
)
328 struct mem_cgroup_per_zone
*mz
;
329 struct page_cgroup
*pc
;
331 if (mem_cgroup_disabled())
334 pc
= lookup_page_cgroup(page
);
336 /* unused page is not rotated. */
337 if (!PageCgroupUsed(pc
))
339 mz
= page_cgroup_zoneinfo(pc
);
340 list_move(&pc
->lru
, &mz
->lists
[lru
]);
343 void mem_cgroup_add_lru_list(struct page
*page
, enum lru_list lru
)
345 struct page_cgroup
*pc
;
346 struct mem_cgroup_per_zone
*mz
;
348 if (mem_cgroup_disabled())
350 pc
= lookup_page_cgroup(page
);
351 /* barrier to sync with "charge" */
353 if (!PageCgroupUsed(pc
))
356 mz
= page_cgroup_zoneinfo(pc
);
357 MEM_CGROUP_ZSTAT(mz
, lru
) += 1;
358 list_add(&pc
->lru
, &mz
->lists
[lru
]);
361 * To add swapcache into LRU. Be careful to all this function.
362 * zone->lru_lock shouldn't be held and irq must not be disabled.
364 static void mem_cgroup_lru_fixup(struct page
*page
)
366 if (!isolate_lru_page(page
))
367 putback_lru_page(page
);
370 void mem_cgroup_move_lists(struct page
*page
,
371 enum lru_list from
, enum lru_list to
)
373 if (mem_cgroup_disabled())
375 mem_cgroup_del_lru_list(page
, from
);
376 mem_cgroup_add_lru_list(page
, to
);
379 int task_in_mem_cgroup(struct task_struct
*task
, const struct mem_cgroup
*mem
)
384 ret
= task
->mm
&& mm_match_cgroup(task
->mm
, mem
);
390 * Calculate mapped_ratio under memory controller. This will be used in
391 * vmscan.c for deteremining we have to reclaim mapped pages.
393 int mem_cgroup_calc_mapped_ratio(struct mem_cgroup
*mem
)
398 * usage is recorded in bytes. But, here, we assume the number of
399 * physical pages can be represented by "long" on any arch.
401 total
= (long) (mem
->res
.usage
>> PAGE_SHIFT
) + 1L;
402 rss
= (long)mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_RSS
);
403 return (int)((rss
* 100L) / total
);
407 * prev_priority control...this will be used in memory reclaim path.
409 int mem_cgroup_get_reclaim_priority(struct mem_cgroup
*mem
)
413 spin_lock(&mem
->reclaim_param_lock
);
414 prev_priority
= mem
->prev_priority
;
415 spin_unlock(&mem
->reclaim_param_lock
);
417 return prev_priority
;
420 void mem_cgroup_note_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
422 spin_lock(&mem
->reclaim_param_lock
);
423 if (priority
< mem
->prev_priority
)
424 mem
->prev_priority
= priority
;
425 spin_unlock(&mem
->reclaim_param_lock
);
428 void mem_cgroup_record_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
430 spin_lock(&mem
->reclaim_param_lock
);
431 mem
->prev_priority
= priority
;
432 spin_unlock(&mem
->reclaim_param_lock
);
435 int mem_cgroup_inactive_anon_is_low(struct mem_cgroup
*memcg
, struct zone
*zone
)
437 unsigned long active
;
438 unsigned long inactive
;
440 inactive
= mem_cgroup_get_all_zonestat(memcg
, LRU_INACTIVE_ANON
);
441 active
= mem_cgroup_get_all_zonestat(memcg
, LRU_ACTIVE_ANON
);
443 if (inactive
* memcg
->inactive_ratio
< active
)
449 unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup
*memcg
,
453 int nid
= zone
->zone_pgdat
->node_id
;
454 int zid
= zone_idx(zone
);
455 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(memcg
, nid
, zid
);
457 return MEM_CGROUP_ZSTAT(mz
, lru
);
460 struct zone_reclaim_stat
*mem_cgroup_get_reclaim_stat(struct mem_cgroup
*memcg
,
463 int nid
= zone
->zone_pgdat
->node_id
;
464 int zid
= zone_idx(zone
);
465 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(memcg
, nid
, zid
);
467 return &mz
->reclaim_stat
;
470 struct zone_reclaim_stat
*
471 mem_cgroup_get_reclaim_stat_from_page(struct page
*page
)
473 struct page_cgroup
*pc
;
474 struct mem_cgroup_per_zone
*mz
;
476 if (mem_cgroup_disabled())
479 pc
= lookup_page_cgroup(page
);
480 mz
= page_cgroup_zoneinfo(pc
);
484 return &mz
->reclaim_stat
;
487 unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan
,
488 struct list_head
*dst
,
489 unsigned long *scanned
, int order
,
490 int mode
, struct zone
*z
,
491 struct mem_cgroup
*mem_cont
,
492 int active
, int file
)
494 unsigned long nr_taken
= 0;
498 struct list_head
*src
;
499 struct page_cgroup
*pc
, *tmp
;
500 int nid
= z
->zone_pgdat
->node_id
;
501 int zid
= zone_idx(z
);
502 struct mem_cgroup_per_zone
*mz
;
503 int lru
= LRU_FILE
* !!file
+ !!active
;
506 mz
= mem_cgroup_zoneinfo(mem_cont
, nid
, zid
);
507 src
= &mz
->lists
[lru
];
510 list_for_each_entry_safe_reverse(pc
, tmp
, src
, lru
) {
511 if (scan
>= nr_to_scan
)
515 if (unlikely(!PageCgroupUsed(pc
)))
517 if (unlikely(!PageLRU(page
)))
521 if (__isolate_lru_page(page
, mode
, file
) == 0) {
522 list_move(&page
->lru
, dst
);
531 #define mem_cgroup_from_res_counter(counter, member) \
532 container_of(counter, struct mem_cgroup, member)
535 * This routine finds the DFS walk successor. This routine should be
536 * called with cgroup_mutex held
538 static struct mem_cgroup
*
539 mem_cgroup_get_next_node(struct mem_cgroup
*curr
, struct mem_cgroup
*root_mem
)
541 struct cgroup
*cgroup
, *curr_cgroup
, *root_cgroup
;
543 curr_cgroup
= curr
->css
.cgroup
;
544 root_cgroup
= root_mem
->css
.cgroup
;
546 if (!list_empty(&curr_cgroup
->children
)) {
548 * Walk down to children
550 mem_cgroup_put(curr
);
551 cgroup
= list_entry(curr_cgroup
->children
.next
,
552 struct cgroup
, sibling
);
553 curr
= mem_cgroup_from_cont(cgroup
);
554 mem_cgroup_get(curr
);
559 if (curr_cgroup
== root_cgroup
) {
560 mem_cgroup_put(curr
);
562 mem_cgroup_get(curr
);
569 if (curr_cgroup
->sibling
.next
!= &curr_cgroup
->parent
->children
) {
570 mem_cgroup_put(curr
);
571 cgroup
= list_entry(curr_cgroup
->sibling
.next
, struct cgroup
,
573 curr
= mem_cgroup_from_cont(cgroup
);
574 mem_cgroup_get(curr
);
579 * Go up to next parent and next parent's sibling if need be
581 curr_cgroup
= curr_cgroup
->parent
;
585 root_mem
->last_scanned_child
= curr
;
590 * Visit the first child (need not be the first child as per the ordering
591 * of the cgroup list, since we track last_scanned_child) of @mem and use
592 * that to reclaim free pages from.
594 static struct mem_cgroup
*
595 mem_cgroup_get_first_node(struct mem_cgroup
*root_mem
)
597 struct cgroup
*cgroup
;
598 struct mem_cgroup
*ret
;
599 bool obsolete
= (root_mem
->last_scanned_child
&&
600 root_mem
->last_scanned_child
->obsolete
);
603 * Scan all children under the mem_cgroup mem
606 if (list_empty(&root_mem
->css
.cgroup
->children
)) {
611 if (!root_mem
->last_scanned_child
|| obsolete
) {
614 mem_cgroup_put(root_mem
->last_scanned_child
);
616 cgroup
= list_first_entry(&root_mem
->css
.cgroup
->children
,
617 struct cgroup
, sibling
);
618 ret
= mem_cgroup_from_cont(cgroup
);
621 ret
= mem_cgroup_get_next_node(root_mem
->last_scanned_child
,
625 root_mem
->last_scanned_child
= ret
;
630 static bool mem_cgroup_check_under_limit(struct mem_cgroup
*mem
)
632 if (do_swap_account
) {
633 if (res_counter_check_under_limit(&mem
->res
) &&
634 res_counter_check_under_limit(&mem
->memsw
))
637 if (res_counter_check_under_limit(&mem
->res
))
642 static unsigned int get_swappiness(struct mem_cgroup
*memcg
)
644 struct cgroup
*cgrp
= memcg
->css
.cgroup
;
645 unsigned int swappiness
;
648 if (cgrp
->parent
== NULL
)
649 return vm_swappiness
;
651 spin_lock(&memcg
->reclaim_param_lock
);
652 swappiness
= memcg
->swappiness
;
653 spin_unlock(&memcg
->reclaim_param_lock
);
659 * Dance down the hierarchy if needed to reclaim memory. We remember the
660 * last child we reclaimed from, so that we don't end up penalizing
661 * one child extensively based on its position in the children list.
663 * root_mem is the original ancestor that we've been reclaim from.
665 static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup
*root_mem
,
666 gfp_t gfp_mask
, bool noswap
)
668 struct mem_cgroup
*next_mem
;
672 * Reclaim unconditionally and don't check for return value.
673 * We need to reclaim in the current group and down the tree.
674 * One might think about checking for children before reclaiming,
675 * but there might be left over accounting, even after children
678 ret
= try_to_free_mem_cgroup_pages(root_mem
, gfp_mask
, noswap
,
679 get_swappiness(root_mem
));
680 if (mem_cgroup_check_under_limit(root_mem
))
682 if (!root_mem
->use_hierarchy
)
685 next_mem
= mem_cgroup_get_first_node(root_mem
);
687 while (next_mem
!= root_mem
) {
688 if (next_mem
->obsolete
) {
689 mem_cgroup_put(next_mem
);
691 next_mem
= mem_cgroup_get_first_node(root_mem
);
695 ret
= try_to_free_mem_cgroup_pages(next_mem
, gfp_mask
, noswap
,
696 get_swappiness(next_mem
));
697 if (mem_cgroup_check_under_limit(root_mem
))
700 next_mem
= mem_cgroup_get_next_node(next_mem
, root_mem
);
706 bool mem_cgroup_oom_called(struct task_struct
*task
)
709 struct mem_cgroup
*mem
;
710 struct mm_struct
*mm
;
716 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
717 if (mem
&& time_before(jiffies
, mem
->last_oom_jiffies
+ HZ
/10))
723 * Unlike exported interface, "oom" parameter is added. if oom==true,
724 * oom-killer can be invoked.
726 static int __mem_cgroup_try_charge(struct mm_struct
*mm
,
727 gfp_t gfp_mask
, struct mem_cgroup
**memcg
,
730 struct mem_cgroup
*mem
, *mem_over_limit
;
731 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
732 struct res_counter
*fail_res
;
734 if (unlikely(test_thread_flag(TIF_MEMDIE
))) {
735 /* Don't account this! */
741 * We always charge the cgroup the mm_struct belongs to.
742 * The mm_struct's mem_cgroup changes on task migration if the
743 * thread group leader migrates. It's possible that mm is not
744 * set, if so charge the init_mm (happens for pagecache usage).
746 if (likely(!*memcg
)) {
748 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
749 if (unlikely(!mem
)) {
754 * For every charge from the cgroup, increment reference count
768 ret
= res_counter_charge(&mem
->res
, PAGE_SIZE
, &fail_res
);
770 if (!do_swap_account
)
772 ret
= res_counter_charge(&mem
->memsw
, PAGE_SIZE
,
776 /* mem+swap counter fails */
777 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
779 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
782 /* mem counter fails */
783 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
786 if (!(gfp_mask
& __GFP_WAIT
))
789 ret
= mem_cgroup_hierarchical_reclaim(mem_over_limit
, gfp_mask
,
793 * try_to_free_mem_cgroup_pages() might not give us a full
794 * picture of reclaim. Some pages are reclaimed and might be
795 * moved to swap cache or just unmapped from the cgroup.
796 * Check the limit again to see if the reclaim reduced the
797 * current usage of the cgroup before giving up
800 if (mem_cgroup_check_under_limit(mem_over_limit
))
805 mem_cgroup_out_of_memory(mem_over_limit
, gfp_mask
);
806 mem_over_limit
->last_oom_jiffies
= jiffies
;
818 * mem_cgroup_try_charge - get charge of PAGE_SIZE.
819 * @mm: an mm_struct which is charged against. (when *memcg is NULL)
820 * @gfp_mask: gfp_mask for reclaim.
821 * @memcg: a pointer to memory cgroup which is charged against.
823 * charge against memory cgroup pointed by *memcg. if *memcg == NULL, estimated
824 * memory cgroup from @mm is got and stored in *memcg.
826 * Returns 0 if success. -ENOMEM at failure.
827 * This call can invoke OOM-Killer.
830 int mem_cgroup_try_charge(struct mm_struct
*mm
,
831 gfp_t mask
, struct mem_cgroup
**memcg
)
833 return __mem_cgroup_try_charge(mm
, mask
, memcg
, true);
837 * commit a charge got by mem_cgroup_try_charge() and makes page_cgroup to be
838 * USED state. If already USED, uncharge and return.
841 static void __mem_cgroup_commit_charge(struct mem_cgroup
*mem
,
842 struct page_cgroup
*pc
,
843 enum charge_type ctype
)
845 /* try_charge() can return NULL to *memcg, taking care of it. */
849 lock_page_cgroup(pc
);
850 if (unlikely(PageCgroupUsed(pc
))) {
851 unlock_page_cgroup(pc
);
852 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
854 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
858 pc
->mem_cgroup
= mem
;
860 pc
->flags
= pcg_default_flags
[ctype
];
862 mem_cgroup_charge_statistics(mem
, pc
, true);
864 unlock_page_cgroup(pc
);
868 * mem_cgroup_move_account - move account of the page
869 * @pc: page_cgroup of the page.
870 * @from: mem_cgroup which the page is moved from.
871 * @to: mem_cgroup which the page is moved to. @from != @to.
873 * The caller must confirm following.
874 * - page is not on LRU (isolate_page() is useful.)
876 * returns 0 at success,
877 * returns -EBUSY when lock is busy or "pc" is unstable.
879 * This function does "uncharge" from old cgroup but doesn't do "charge" to
880 * new cgroup. It should be done by a caller.
883 static int mem_cgroup_move_account(struct page_cgroup
*pc
,
884 struct mem_cgroup
*from
, struct mem_cgroup
*to
)
886 struct mem_cgroup_per_zone
*from_mz
, *to_mz
;
890 VM_BUG_ON(from
== to
);
891 VM_BUG_ON(PageLRU(pc
->page
));
893 nid
= page_cgroup_nid(pc
);
894 zid
= page_cgroup_zid(pc
);
895 from_mz
= mem_cgroup_zoneinfo(from
, nid
, zid
);
896 to_mz
= mem_cgroup_zoneinfo(to
, nid
, zid
);
898 if (!trylock_page_cgroup(pc
))
901 if (!PageCgroupUsed(pc
))
904 if (pc
->mem_cgroup
!= from
)
908 res_counter_uncharge(&from
->res
, PAGE_SIZE
);
909 mem_cgroup_charge_statistics(from
, pc
, false);
911 res_counter_uncharge(&from
->memsw
, PAGE_SIZE
);
913 mem_cgroup_charge_statistics(to
, pc
, true);
917 unlock_page_cgroup(pc
);
922 * move charges to its parent.
925 static int mem_cgroup_move_parent(struct page_cgroup
*pc
,
926 struct mem_cgroup
*child
,
929 struct page
*page
= pc
->page
;
930 struct cgroup
*cg
= child
->css
.cgroup
;
931 struct cgroup
*pcg
= cg
->parent
;
932 struct mem_cgroup
*parent
;
940 parent
= mem_cgroup_from_cont(pcg
);
943 ret
= __mem_cgroup_try_charge(NULL
, gfp_mask
, &parent
, false);
947 if (!get_page_unless_zero(page
))
950 ret
= isolate_lru_page(page
);
955 ret
= mem_cgroup_move_account(pc
, child
, parent
);
957 /* drop extra refcnt by try_charge() (move_account increment one) */
958 css_put(&parent
->css
);
959 putback_lru_page(page
);
964 /* uncharge if move fails */
966 res_counter_uncharge(&parent
->res
, PAGE_SIZE
);
968 res_counter_uncharge(&parent
->memsw
, PAGE_SIZE
);
974 * Charge the memory controller for page usage.
976 * 0 if the charge was successful
977 * < 0 if the cgroup is over its limit
979 static int mem_cgroup_charge_common(struct page
*page
, struct mm_struct
*mm
,
980 gfp_t gfp_mask
, enum charge_type ctype
,
981 struct mem_cgroup
*memcg
)
983 struct mem_cgroup
*mem
;
984 struct page_cgroup
*pc
;
987 pc
= lookup_page_cgroup(page
);
988 /* can happen at boot */
994 ret
= __mem_cgroup_try_charge(mm
, gfp_mask
, &mem
, true);
998 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
1002 int mem_cgroup_newpage_charge(struct page
*page
,
1003 struct mm_struct
*mm
, gfp_t gfp_mask
)
1005 if (mem_cgroup_disabled())
1007 if (PageCompound(page
))
1010 * If already mapped, we don't have to account.
1011 * If page cache, page->mapping has address_space.
1012 * But page->mapping may have out-of-use anon_vma pointer,
1013 * detecit it by PageAnon() check. newly-mapped-anon's page->mapping
1016 if (page_mapped(page
) || (page
->mapping
&& !PageAnon(page
)))
1020 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1021 MEM_CGROUP_CHARGE_TYPE_MAPPED
, NULL
);
1024 int mem_cgroup_cache_charge(struct page
*page
, struct mm_struct
*mm
,
1027 if (mem_cgroup_disabled())
1029 if (PageCompound(page
))
1032 * Corner case handling. This is called from add_to_page_cache()
1033 * in usual. But some FS (shmem) precharges this page before calling it
1034 * and call add_to_page_cache() with GFP_NOWAIT.
1036 * For GFP_NOWAIT case, the page may be pre-charged before calling
1037 * add_to_page_cache(). (See shmem.c) check it here and avoid to call
1038 * charge twice. (It works but has to pay a bit larger cost.)
1040 if (!(gfp_mask
& __GFP_WAIT
)) {
1041 struct page_cgroup
*pc
;
1044 pc
= lookup_page_cgroup(page
);
1047 lock_page_cgroup(pc
);
1048 if (PageCgroupUsed(pc
)) {
1049 unlock_page_cgroup(pc
);
1052 unlock_page_cgroup(pc
);
1058 if (page_is_file_cache(page
))
1059 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1060 MEM_CGROUP_CHARGE_TYPE_CACHE
, NULL
);
1062 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1063 MEM_CGROUP_CHARGE_TYPE_SHMEM
, NULL
);
1066 int mem_cgroup_try_charge_swapin(struct mm_struct
*mm
,
1068 gfp_t mask
, struct mem_cgroup
**ptr
)
1070 struct mem_cgroup
*mem
;
1073 if (mem_cgroup_disabled())
1076 if (!do_swap_account
)
1080 * A racing thread's fault, or swapoff, may have already updated
1081 * the pte, and even removed page from swap cache: return success
1082 * to go on to do_swap_page()'s pte_same() test, which should fail.
1084 if (!PageSwapCache(page
))
1087 ent
.val
= page_private(page
);
1089 mem
= lookup_swap_cgroup(ent
);
1090 if (!mem
|| mem
->obsolete
)
1093 return __mem_cgroup_try_charge(NULL
, mask
, ptr
, true);
1097 return __mem_cgroup_try_charge(mm
, mask
, ptr
, true);
1102 int mem_cgroup_cache_charge_swapin(struct page
*page
,
1103 struct mm_struct
*mm
, gfp_t mask
, bool locked
)
1107 if (mem_cgroup_disabled())
1114 * If not locked, the page can be dropped from SwapCache until
1117 if (PageSwapCache(page
)) {
1118 struct mem_cgroup
*mem
= NULL
;
1121 ent
.val
= page_private(page
);
1122 if (do_swap_account
) {
1123 mem
= lookup_swap_cgroup(ent
);
1124 if (mem
&& mem
->obsolete
)
1129 ret
= mem_cgroup_charge_common(page
, mm
, mask
,
1130 MEM_CGROUP_CHARGE_TYPE_SHMEM
, mem
);
1132 if (!ret
&& do_swap_account
) {
1133 /* avoid double counting */
1134 mem
= swap_cgroup_record(ent
, NULL
);
1136 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1137 mem_cgroup_put(mem
);
1143 /* add this page(page_cgroup) to the LRU we want. */
1144 mem_cgroup_lru_fixup(page
);
1150 void mem_cgroup_commit_charge_swapin(struct page
*page
, struct mem_cgroup
*ptr
)
1152 struct page_cgroup
*pc
;
1154 if (mem_cgroup_disabled())
1158 pc
= lookup_page_cgroup(page
);
1159 __mem_cgroup_commit_charge(ptr
, pc
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1161 * Now swap is on-memory. This means this page may be
1162 * counted both as mem and swap....double count.
1163 * Fix it by uncharging from memsw. This SwapCache is stable
1164 * because we're still under lock_page().
1166 if (do_swap_account
) {
1167 swp_entry_t ent
= {.val
= page_private(page
)};
1168 struct mem_cgroup
*memcg
;
1169 memcg
= swap_cgroup_record(ent
, NULL
);
1171 /* If memcg is obsolete, memcg can be != ptr */
1172 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1173 mem_cgroup_put(memcg
);
1177 /* add this page(page_cgroup) to the LRU we want. */
1178 mem_cgroup_lru_fixup(page
);
1181 void mem_cgroup_cancel_charge_swapin(struct mem_cgroup
*mem
)
1183 if (mem_cgroup_disabled())
1187 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1188 if (do_swap_account
)
1189 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1195 * uncharge if !page_mapped(page)
1197 static struct mem_cgroup
*
1198 __mem_cgroup_uncharge_common(struct page
*page
, enum charge_type ctype
)
1200 struct page_cgroup
*pc
;
1201 struct mem_cgroup
*mem
= NULL
;
1202 struct mem_cgroup_per_zone
*mz
;
1204 if (mem_cgroup_disabled())
1207 if (PageSwapCache(page
))
1211 * Check if our page_cgroup is valid
1213 pc
= lookup_page_cgroup(page
);
1214 if (unlikely(!pc
|| !PageCgroupUsed(pc
)))
1217 lock_page_cgroup(pc
);
1219 mem
= pc
->mem_cgroup
;
1221 if (!PageCgroupUsed(pc
))
1225 case MEM_CGROUP_CHARGE_TYPE_MAPPED
:
1226 if (page_mapped(page
))
1229 case MEM_CGROUP_CHARGE_TYPE_SWAPOUT
:
1230 if (!PageAnon(page
)) { /* Shared memory */
1231 if (page
->mapping
&& !page_is_file_cache(page
))
1233 } else if (page_mapped(page
)) /* Anon */
1240 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1241 if (do_swap_account
&& (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
))
1242 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1244 mem_cgroup_charge_statistics(mem
, pc
, false);
1245 ClearPageCgroupUsed(pc
);
1247 mz
= page_cgroup_zoneinfo(pc
);
1248 unlock_page_cgroup(pc
);
1250 /* at swapout, this memcg will be accessed to record to swap */
1251 if (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
)
1257 unlock_page_cgroup(pc
);
1261 void mem_cgroup_uncharge_page(struct page
*page
)
1264 if (page_mapped(page
))
1266 if (page
->mapping
&& !PageAnon(page
))
1268 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1271 void mem_cgroup_uncharge_cache_page(struct page
*page
)
1273 VM_BUG_ON(page_mapped(page
));
1274 VM_BUG_ON(page
->mapping
);
1275 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_CACHE
);
1279 * called from __delete_from_swap_cache() and drop "page" account.
1280 * memcg information is recorded to swap_cgroup of "ent"
1282 void mem_cgroup_uncharge_swapcache(struct page
*page
, swp_entry_t ent
)
1284 struct mem_cgroup
*memcg
;
1286 memcg
= __mem_cgroup_uncharge_common(page
,
1287 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
);
1288 /* record memcg information */
1289 if (do_swap_account
&& memcg
) {
1290 swap_cgroup_record(ent
, memcg
);
1291 mem_cgroup_get(memcg
);
1294 css_put(&memcg
->css
);
1297 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1299 * called from swap_entry_free(). remove record in swap_cgroup and
1300 * uncharge "memsw" account.
1302 void mem_cgroup_uncharge_swap(swp_entry_t ent
)
1304 struct mem_cgroup
*memcg
;
1306 if (!do_swap_account
)
1309 memcg
= swap_cgroup_record(ent
, NULL
);
1311 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1312 mem_cgroup_put(memcg
);
1318 * Before starting migration, account PAGE_SIZE to mem_cgroup that the old
1321 int mem_cgroup_prepare_migration(struct page
*page
, struct mem_cgroup
**ptr
)
1323 struct page_cgroup
*pc
;
1324 struct mem_cgroup
*mem
= NULL
;
1327 if (mem_cgroup_disabled())
1330 pc
= lookup_page_cgroup(page
);
1331 lock_page_cgroup(pc
);
1332 if (PageCgroupUsed(pc
)) {
1333 mem
= pc
->mem_cgroup
;
1336 unlock_page_cgroup(pc
);
1339 ret
= mem_cgroup_try_charge(NULL
, GFP_KERNEL
, &mem
);
1346 /* remove redundant charge if migration failed*/
1347 void mem_cgroup_end_migration(struct mem_cgroup
*mem
,
1348 struct page
*oldpage
, struct page
*newpage
)
1350 struct page
*target
, *unused
;
1351 struct page_cgroup
*pc
;
1352 enum charge_type ctype
;
1357 /* at migration success, oldpage->mapping is NULL. */
1358 if (oldpage
->mapping
) {
1366 if (PageAnon(target
))
1367 ctype
= MEM_CGROUP_CHARGE_TYPE_MAPPED
;
1368 else if (page_is_file_cache(target
))
1369 ctype
= MEM_CGROUP_CHARGE_TYPE_CACHE
;
1371 ctype
= MEM_CGROUP_CHARGE_TYPE_SHMEM
;
1373 /* unused page is not on radix-tree now. */
1375 __mem_cgroup_uncharge_common(unused
, ctype
);
1377 pc
= lookup_page_cgroup(target
);
1379 * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
1380 * So, double-counting is effectively avoided.
1382 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
1385 * Both of oldpage and newpage are still under lock_page().
1386 * Then, we don't have to care about race in radix-tree.
1387 * But we have to be careful that this page is unmapped or not.
1389 * There is a case for !page_mapped(). At the start of
1390 * migration, oldpage was mapped. But now, it's zapped.
1391 * But we know *target* page is not freed/reused under us.
1392 * mem_cgroup_uncharge_page() does all necessary checks.
1394 if (ctype
== MEM_CGROUP_CHARGE_TYPE_MAPPED
)
1395 mem_cgroup_uncharge_page(target
);
1399 * A call to try to shrink memory usage under specified resource controller.
1400 * This is typically used for page reclaiming for shmem for reducing side
1401 * effect of page allocation from shmem, which is used by some mem_cgroup.
1403 int mem_cgroup_shrink_usage(struct mm_struct
*mm
, gfp_t gfp_mask
)
1405 struct mem_cgroup
*mem
;
1407 int retry
= MEM_CGROUP_RECLAIM_RETRIES
;
1409 if (mem_cgroup_disabled())
1415 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
1416 if (unlikely(!mem
)) {
1424 progress
= try_to_free_mem_cgroup_pages(mem
, gfp_mask
, true,
1425 get_swappiness(mem
));
1426 progress
+= mem_cgroup_check_under_limit(mem
);
1427 } while (!progress
&& --retry
);
1436 * The inactive anon list should be small enough that the VM never has to
1437 * do too much work, but large enough that each inactive page has a chance
1438 * to be referenced again before it is swapped out.
1440 * this calculation is straightforward porting from
1441 * page_alloc.c::setup_per_zone_inactive_ratio().
1442 * it describe more detail.
1444 static void mem_cgroup_set_inactive_ratio(struct mem_cgroup
*memcg
)
1446 unsigned int gb
, ratio
;
1448 gb
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
) >> 30;
1450 ratio
= int_sqrt(10 * gb
);
1454 memcg
->inactive_ratio
= ratio
;
1458 static DEFINE_MUTEX(set_limit_mutex
);
1460 static int mem_cgroup_resize_limit(struct mem_cgroup
*memcg
,
1461 unsigned long long val
)
1464 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1469 while (retry_count
) {
1470 if (signal_pending(current
)) {
1475 * Rather than hide all in some function, I do this in
1476 * open coded manner. You see what this really does.
1477 * We have to guarantee mem->res.limit < mem->memsw.limit.
1479 mutex_lock(&set_limit_mutex
);
1480 memswlimit
= res_counter_read_u64(&memcg
->memsw
, RES_LIMIT
);
1481 if (memswlimit
< val
) {
1483 mutex_unlock(&set_limit_mutex
);
1486 ret
= res_counter_set_limit(&memcg
->res
, val
);
1487 mutex_unlock(&set_limit_mutex
);
1492 progress
= try_to_free_mem_cgroup_pages(memcg
,
1495 get_swappiness(memcg
));
1496 if (!progress
) retry_count
--;
1500 mem_cgroup_set_inactive_ratio(memcg
);
1505 int mem_cgroup_resize_memsw_limit(struct mem_cgroup
*memcg
,
1506 unsigned long long val
)
1508 int retry_count
= MEM_CGROUP_RECLAIM_RETRIES
;
1509 u64 memlimit
, oldusage
, curusage
;
1512 if (!do_swap_account
)
1515 while (retry_count
) {
1516 if (signal_pending(current
)) {
1521 * Rather than hide all in some function, I do this in
1522 * open coded manner. You see what this really does.
1523 * We have to guarantee mem->res.limit < mem->memsw.limit.
1525 mutex_lock(&set_limit_mutex
);
1526 memlimit
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
);
1527 if (memlimit
> val
) {
1529 mutex_unlock(&set_limit_mutex
);
1532 ret
= res_counter_set_limit(&memcg
->memsw
, val
);
1533 mutex_unlock(&set_limit_mutex
);
1538 oldusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1539 try_to_free_mem_cgroup_pages(memcg
, GFP_KERNEL
, true,
1540 get_swappiness(memcg
));
1541 curusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
1542 if (curusage
>= oldusage
)
1549 * This routine traverse page_cgroup in given list and drop them all.
1550 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
1552 static int mem_cgroup_force_empty_list(struct mem_cgroup
*mem
,
1553 int node
, int zid
, enum lru_list lru
)
1556 struct mem_cgroup_per_zone
*mz
;
1557 struct page_cgroup
*pc
, *busy
;
1558 unsigned long flags
, loop
;
1559 struct list_head
*list
;
1562 zone
= &NODE_DATA(node
)->node_zones
[zid
];
1563 mz
= mem_cgroup_zoneinfo(mem
, node
, zid
);
1564 list
= &mz
->lists
[lru
];
1566 loop
= MEM_CGROUP_ZSTAT(mz
, lru
);
1567 /* give some margin against EBUSY etc...*/
1572 spin_lock_irqsave(&zone
->lru_lock
, flags
);
1573 if (list_empty(list
)) {
1574 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1577 pc
= list_entry(list
->prev
, struct page_cgroup
, lru
);
1579 list_move(&pc
->lru
, list
);
1581 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1584 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
1586 ret
= mem_cgroup_move_parent(pc
, mem
, GFP_KERNEL
);
1590 if (ret
== -EBUSY
|| ret
== -EINVAL
) {
1591 /* found lock contention or "pc" is obsolete. */
1598 if (!ret
&& !list_empty(list
))
1604 * make mem_cgroup's charge to be 0 if there is no task.
1605 * This enables deleting this mem_cgroup.
1607 static int mem_cgroup_force_empty(struct mem_cgroup
*mem
, bool free_all
)
1610 int node
, zid
, shrink
;
1611 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
1612 struct cgroup
*cgrp
= mem
->css
.cgroup
;
1617 /* should free all ? */
1621 while (mem
->res
.usage
> 0) {
1623 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
))
1626 if (signal_pending(current
))
1628 /* This is for making all *used* pages to be on LRU. */
1629 lru_add_drain_all();
1631 for_each_node_state(node
, N_POSSIBLE
) {
1632 for (zid
= 0; !ret
&& zid
< MAX_NR_ZONES
; zid
++) {
1635 ret
= mem_cgroup_force_empty_list(mem
,
1644 /* it seems parent cgroup doesn't have enough mem */
1655 /* returns EBUSY if there is a task or if we come here twice. */
1656 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
) || shrink
) {
1660 /* we call try-to-free pages for make this cgroup empty */
1661 lru_add_drain_all();
1662 /* try to free all pages in this cgroup */
1664 while (nr_retries
&& mem
->res
.usage
> 0) {
1667 if (signal_pending(current
)) {
1671 progress
= try_to_free_mem_cgroup_pages(mem
, GFP_KERNEL
,
1672 false, get_swappiness(mem
));
1675 /* maybe some writeback is necessary */
1676 congestion_wait(WRITE
, HZ
/10);
1681 /* try move_account...there may be some *locked* pages. */
1688 int mem_cgroup_force_empty_write(struct cgroup
*cont
, unsigned int event
)
1690 return mem_cgroup_force_empty(mem_cgroup_from_cont(cont
), true);
1694 static u64
mem_cgroup_hierarchy_read(struct cgroup
*cont
, struct cftype
*cft
)
1696 return mem_cgroup_from_cont(cont
)->use_hierarchy
;
1699 static int mem_cgroup_hierarchy_write(struct cgroup
*cont
, struct cftype
*cft
,
1703 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1704 struct cgroup
*parent
= cont
->parent
;
1705 struct mem_cgroup
*parent_mem
= NULL
;
1708 parent_mem
= mem_cgroup_from_cont(parent
);
1712 * If parent's use_hiearchy is set, we can't make any modifications
1713 * in the child subtrees. If it is unset, then the change can
1714 * occur, provided the current cgroup has no children.
1716 * For the root cgroup, parent_mem is NULL, we allow value to be
1717 * set if there are no children.
1719 if ((!parent_mem
|| !parent_mem
->use_hierarchy
) &&
1720 (val
== 1 || val
== 0)) {
1721 if (list_empty(&cont
->children
))
1722 mem
->use_hierarchy
= val
;
1732 static u64
mem_cgroup_read(struct cgroup
*cont
, struct cftype
*cft
)
1734 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
1738 type
= MEMFILE_TYPE(cft
->private);
1739 name
= MEMFILE_ATTR(cft
->private);
1742 val
= res_counter_read_u64(&mem
->res
, name
);
1745 if (do_swap_account
)
1746 val
= res_counter_read_u64(&mem
->memsw
, name
);
1755 * The user of this function is...
1758 static int mem_cgroup_write(struct cgroup
*cont
, struct cftype
*cft
,
1761 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cont
);
1763 unsigned long long val
;
1766 type
= MEMFILE_TYPE(cft
->private);
1767 name
= MEMFILE_ATTR(cft
->private);
1770 /* This function does all necessary parse...reuse it */
1771 ret
= res_counter_memparse_write_strategy(buffer
, &val
);
1775 ret
= mem_cgroup_resize_limit(memcg
, val
);
1777 ret
= mem_cgroup_resize_memsw_limit(memcg
, val
);
1780 ret
= -EINVAL
; /* should be BUG() ? */
1786 static int mem_cgroup_reset(struct cgroup
*cont
, unsigned int event
)
1788 struct mem_cgroup
*mem
;
1791 mem
= mem_cgroup_from_cont(cont
);
1792 type
= MEMFILE_TYPE(event
);
1793 name
= MEMFILE_ATTR(event
);
1797 res_counter_reset_max(&mem
->res
);
1799 res_counter_reset_max(&mem
->memsw
);
1803 res_counter_reset_failcnt(&mem
->res
);
1805 res_counter_reset_failcnt(&mem
->memsw
);
1811 static const struct mem_cgroup_stat_desc
{
1814 } mem_cgroup_stat_desc
[] = {
1815 [MEM_CGROUP_STAT_CACHE
] = { "cache", PAGE_SIZE
, },
1816 [MEM_CGROUP_STAT_RSS
] = { "rss", PAGE_SIZE
, },
1817 [MEM_CGROUP_STAT_PGPGIN_COUNT
] = {"pgpgin", 1, },
1818 [MEM_CGROUP_STAT_PGPGOUT_COUNT
] = {"pgpgout", 1, },
1821 static int mem_control_stat_show(struct cgroup
*cont
, struct cftype
*cft
,
1822 struct cgroup_map_cb
*cb
)
1824 struct mem_cgroup
*mem_cont
= mem_cgroup_from_cont(cont
);
1825 struct mem_cgroup_stat
*stat
= &mem_cont
->stat
;
1828 for (i
= 0; i
< ARRAY_SIZE(stat
->cpustat
[0].count
); i
++) {
1831 val
= mem_cgroup_read_stat(stat
, i
);
1832 val
*= mem_cgroup_stat_desc
[i
].unit
;
1833 cb
->fill(cb
, mem_cgroup_stat_desc
[i
].msg
, val
);
1835 /* showing # of active pages */
1837 unsigned long active_anon
, inactive_anon
;
1838 unsigned long active_file
, inactive_file
;
1839 unsigned long unevictable
;
1841 inactive_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1843 active_anon
= mem_cgroup_get_all_zonestat(mem_cont
,
1845 inactive_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1847 active_file
= mem_cgroup_get_all_zonestat(mem_cont
,
1849 unevictable
= mem_cgroup_get_all_zonestat(mem_cont
,
1852 cb
->fill(cb
, "active_anon", (active_anon
) * PAGE_SIZE
);
1853 cb
->fill(cb
, "inactive_anon", (inactive_anon
) * PAGE_SIZE
);
1854 cb
->fill(cb
, "active_file", (active_file
) * PAGE_SIZE
);
1855 cb
->fill(cb
, "inactive_file", (inactive_file
) * PAGE_SIZE
);
1856 cb
->fill(cb
, "unevictable", unevictable
* PAGE_SIZE
);
1860 #ifdef CONFIG_DEBUG_VM
1861 cb
->fill(cb
, "inactive_ratio", mem_cont
->inactive_ratio
);
1865 struct mem_cgroup_per_zone
*mz
;
1866 unsigned long recent_rotated
[2] = {0, 0};
1867 unsigned long recent_scanned
[2] = {0, 0};
1869 for_each_online_node(nid
)
1870 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
1871 mz
= mem_cgroup_zoneinfo(mem_cont
, nid
, zid
);
1873 recent_rotated
[0] +=
1874 mz
->reclaim_stat
.recent_rotated
[0];
1875 recent_rotated
[1] +=
1876 mz
->reclaim_stat
.recent_rotated
[1];
1877 recent_scanned
[0] +=
1878 mz
->reclaim_stat
.recent_scanned
[0];
1879 recent_scanned
[1] +=
1880 mz
->reclaim_stat
.recent_scanned
[1];
1882 cb
->fill(cb
, "recent_rotated_anon", recent_rotated
[0]);
1883 cb
->fill(cb
, "recent_rotated_file", recent_rotated
[1]);
1884 cb
->fill(cb
, "recent_scanned_anon", recent_scanned
[0]);
1885 cb
->fill(cb
, "recent_scanned_file", recent_scanned
[1]);
1892 static u64
mem_cgroup_swappiness_read(struct cgroup
*cgrp
, struct cftype
*cft
)
1894 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cgrp
);
1896 return get_swappiness(memcg
);
1899 static int mem_cgroup_swappiness_write(struct cgroup
*cgrp
, struct cftype
*cft
,
1902 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cgrp
);
1903 struct mem_cgroup
*parent
;
1907 if (cgrp
->parent
== NULL
)
1910 parent
= mem_cgroup_from_cont(cgrp
->parent
);
1911 /* If under hierarchy, only empty-root can set this value */
1912 if ((parent
->use_hierarchy
) ||
1913 (memcg
->use_hierarchy
&& !list_empty(&cgrp
->children
)))
1916 spin_lock(&memcg
->reclaim_param_lock
);
1917 memcg
->swappiness
= val
;
1918 spin_unlock(&memcg
->reclaim_param_lock
);
1924 static struct cftype mem_cgroup_files
[] = {
1926 .name
= "usage_in_bytes",
1927 .private = MEMFILE_PRIVATE(_MEM
, RES_USAGE
),
1928 .read_u64
= mem_cgroup_read
,
1931 .name
= "max_usage_in_bytes",
1932 .private = MEMFILE_PRIVATE(_MEM
, RES_MAX_USAGE
),
1933 .trigger
= mem_cgroup_reset
,
1934 .read_u64
= mem_cgroup_read
,
1937 .name
= "limit_in_bytes",
1938 .private = MEMFILE_PRIVATE(_MEM
, RES_LIMIT
),
1939 .write_string
= mem_cgroup_write
,
1940 .read_u64
= mem_cgroup_read
,
1944 .private = MEMFILE_PRIVATE(_MEM
, RES_FAILCNT
),
1945 .trigger
= mem_cgroup_reset
,
1946 .read_u64
= mem_cgroup_read
,
1950 .read_map
= mem_control_stat_show
,
1953 .name
= "force_empty",
1954 .trigger
= mem_cgroup_force_empty_write
,
1957 .name
= "use_hierarchy",
1958 .write_u64
= mem_cgroup_hierarchy_write
,
1959 .read_u64
= mem_cgroup_hierarchy_read
,
1962 .name
= "swappiness",
1963 .read_u64
= mem_cgroup_swappiness_read
,
1964 .write_u64
= mem_cgroup_swappiness_write
,
1968 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1969 static struct cftype memsw_cgroup_files
[] = {
1971 .name
= "memsw.usage_in_bytes",
1972 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_USAGE
),
1973 .read_u64
= mem_cgroup_read
,
1976 .name
= "memsw.max_usage_in_bytes",
1977 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_MAX_USAGE
),
1978 .trigger
= mem_cgroup_reset
,
1979 .read_u64
= mem_cgroup_read
,
1982 .name
= "memsw.limit_in_bytes",
1983 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_LIMIT
),
1984 .write_string
= mem_cgroup_write
,
1985 .read_u64
= mem_cgroup_read
,
1988 .name
= "memsw.failcnt",
1989 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_FAILCNT
),
1990 .trigger
= mem_cgroup_reset
,
1991 .read_u64
= mem_cgroup_read
,
1995 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
1997 if (!do_swap_account
)
1999 return cgroup_add_files(cont
, ss
, memsw_cgroup_files
,
2000 ARRAY_SIZE(memsw_cgroup_files
));
2003 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
2009 static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
2011 struct mem_cgroup_per_node
*pn
;
2012 struct mem_cgroup_per_zone
*mz
;
2014 int zone
, tmp
= node
;
2016 * This routine is called against possible nodes.
2017 * But it's BUG to call kmalloc() against offline node.
2019 * TODO: this routine can waste much memory for nodes which will
2020 * never be onlined. It's better to use memory hotplug callback
2023 if (!node_state(node
, N_NORMAL_MEMORY
))
2025 pn
= kmalloc_node(sizeof(*pn
), GFP_KERNEL
, tmp
);
2029 mem
->info
.nodeinfo
[node
] = pn
;
2030 memset(pn
, 0, sizeof(*pn
));
2032 for (zone
= 0; zone
< MAX_NR_ZONES
; zone
++) {
2033 mz
= &pn
->zoneinfo
[zone
];
2035 INIT_LIST_HEAD(&mz
->lists
[l
]);
2040 static void free_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
2042 kfree(mem
->info
.nodeinfo
[node
]);
2045 static int mem_cgroup_size(void)
2047 int cpustat_size
= nr_cpu_ids
* sizeof(struct mem_cgroup_stat_cpu
);
2048 return sizeof(struct mem_cgroup
) + cpustat_size
;
2051 static struct mem_cgroup
*mem_cgroup_alloc(void)
2053 struct mem_cgroup
*mem
;
2054 int size
= mem_cgroup_size();
2056 if (size
< PAGE_SIZE
)
2057 mem
= kmalloc(size
, GFP_KERNEL
);
2059 mem
= vmalloc(size
);
2062 memset(mem
, 0, size
);
2067 * At destroying mem_cgroup, references from swap_cgroup can remain.
2068 * (scanning all at force_empty is too costly...)
2070 * Instead of clearing all references at force_empty, we remember
2071 * the number of reference from swap_cgroup and free mem_cgroup when
2072 * it goes down to 0.
2074 * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and
2075 * entry which points to this memcg will be ignore at swapin.
2077 * Removal of cgroup itself succeeds regardless of refs from swap.
2080 static void mem_cgroup_free(struct mem_cgroup
*mem
)
2084 if (atomic_read(&mem
->refcnt
) > 0)
2088 for_each_node_state(node
, N_POSSIBLE
)
2089 free_mem_cgroup_per_zone_info(mem
, node
);
2091 if (mem_cgroup_size() < PAGE_SIZE
)
2097 static void mem_cgroup_get(struct mem_cgroup
*mem
)
2099 atomic_inc(&mem
->refcnt
);
2102 static void mem_cgroup_put(struct mem_cgroup
*mem
)
2104 if (atomic_dec_and_test(&mem
->refcnt
)) {
2107 mem_cgroup_free(mem
);
2112 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2113 static void __init
enable_swap_cgroup(void)
2115 if (!mem_cgroup_disabled() && really_do_swap_account
)
2116 do_swap_account
= 1;
2119 static void __init
enable_swap_cgroup(void)
2124 static struct cgroup_subsys_state
*
2125 mem_cgroup_create(struct cgroup_subsys
*ss
, struct cgroup
*cont
)
2127 struct mem_cgroup
*mem
, *parent
;
2130 mem
= mem_cgroup_alloc();
2132 return ERR_PTR(-ENOMEM
);
2134 for_each_node_state(node
, N_POSSIBLE
)
2135 if (alloc_mem_cgroup_per_zone_info(mem
, node
))
2138 if (cont
->parent
== NULL
) {
2139 enable_swap_cgroup();
2142 parent
= mem_cgroup_from_cont(cont
->parent
);
2143 mem
->use_hierarchy
= parent
->use_hierarchy
;
2146 if (parent
&& parent
->use_hierarchy
) {
2147 res_counter_init(&mem
->res
, &parent
->res
);
2148 res_counter_init(&mem
->memsw
, &parent
->memsw
);
2150 res_counter_init(&mem
->res
, NULL
);
2151 res_counter_init(&mem
->memsw
, NULL
);
2153 mem_cgroup_set_inactive_ratio(mem
);
2154 mem
->last_scanned_child
= NULL
;
2155 spin_lock_init(&mem
->reclaim_param_lock
);
2158 mem
->swappiness
= get_swappiness(parent
);
2162 for_each_node_state(node
, N_POSSIBLE
)
2163 free_mem_cgroup_per_zone_info(mem
, node
);
2164 mem_cgroup_free(mem
);
2165 return ERR_PTR(-ENOMEM
);
2168 static void mem_cgroup_pre_destroy(struct cgroup_subsys
*ss
,
2169 struct cgroup
*cont
)
2171 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
2173 mem_cgroup_force_empty(mem
, false);
2176 static void mem_cgroup_destroy(struct cgroup_subsys
*ss
,
2177 struct cgroup
*cont
)
2179 mem_cgroup_free(mem_cgroup_from_cont(cont
));
2182 static int mem_cgroup_populate(struct cgroup_subsys
*ss
,
2183 struct cgroup
*cont
)
2187 ret
= cgroup_add_files(cont
, ss
, mem_cgroup_files
,
2188 ARRAY_SIZE(mem_cgroup_files
));
2191 ret
= register_memsw_files(cont
, ss
);
2195 static void mem_cgroup_move_task(struct cgroup_subsys
*ss
,
2196 struct cgroup
*cont
,
2197 struct cgroup
*old_cont
,
2198 struct task_struct
*p
)
2201 * FIXME: It's better to move charges of this process from old
2202 * memcg to new memcg. But it's just on TODO-List now.
2206 struct cgroup_subsys mem_cgroup_subsys
= {
2208 .subsys_id
= mem_cgroup_subsys_id
,
2209 .create
= mem_cgroup_create
,
2210 .pre_destroy
= mem_cgroup_pre_destroy
,
2211 .destroy
= mem_cgroup_destroy
,
2212 .populate
= mem_cgroup_populate
,
2213 .attach
= mem_cgroup_move_task
,
2217 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2219 static int __init
disable_swap_account(char *s
)
2221 really_do_swap_account
= 0;
2224 __setup("noswapaccount", disable_swap_account
);