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/limits.h>
31 #include <linux/mutex.h>
32 #include <linux/rbtree.h>
33 #include <linux/slab.h>
34 #include <linux/swap.h>
35 #include <linux/spinlock.h>
37 #include <linux/seq_file.h>
38 #include <linux/vmalloc.h>
39 #include <linux/mm_inline.h>
40 #include <linux/page_cgroup.h>
43 #include <asm/uaccess.h>
45 struct cgroup_subsys mem_cgroup_subsys __read_mostly
;
46 #define MEM_CGROUP_RECLAIM_RETRIES 5
47 struct mem_cgroup
*root_mem_cgroup __read_mostly
;
49 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
50 /* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */
51 int do_swap_account __read_mostly
;
52 static int really_do_swap_account __initdata
= 1; /* for remember boot option*/
54 #define do_swap_account (0)
57 static DEFINE_MUTEX(memcg_tasklist
); /* can be hold under cgroup_mutex */
58 #define SOFTLIMIT_EVENTS_THRESH (1000)
61 * Statistics for memory cgroup.
63 enum mem_cgroup_stat_index
{
65 * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
67 MEM_CGROUP_STAT_CACHE
, /* # of pages charged as cache */
68 MEM_CGROUP_STAT_RSS
, /* # of pages charged as anon rss */
69 MEM_CGROUP_STAT_MAPPED_FILE
, /* # of pages charged as file rss */
70 MEM_CGROUP_STAT_PGPGIN_COUNT
, /* # of pages paged in */
71 MEM_CGROUP_STAT_PGPGOUT_COUNT
, /* # of pages paged out */
72 MEM_CGROUP_STAT_EVENTS
, /* sum of pagein + pageout for internal use */
73 MEM_CGROUP_STAT_SWAPOUT
, /* # of pages, swapped out */
75 MEM_CGROUP_STAT_NSTATS
,
78 struct mem_cgroup_stat_cpu
{
79 s64 count
[MEM_CGROUP_STAT_NSTATS
];
80 } ____cacheline_aligned_in_smp
;
82 struct mem_cgroup_stat
{
83 struct mem_cgroup_stat_cpu cpustat
[0];
87 __mem_cgroup_stat_reset_safe(struct mem_cgroup_stat_cpu
*stat
,
88 enum mem_cgroup_stat_index idx
)
94 __mem_cgroup_stat_read_local(struct mem_cgroup_stat_cpu
*stat
,
95 enum mem_cgroup_stat_index idx
)
97 return stat
->count
[idx
];
101 * For accounting under irq disable, no need for increment preempt count.
103 static inline void __mem_cgroup_stat_add_safe(struct mem_cgroup_stat_cpu
*stat
,
104 enum mem_cgroup_stat_index idx
, int val
)
106 stat
->count
[idx
] += val
;
109 static s64
mem_cgroup_read_stat(struct mem_cgroup_stat
*stat
,
110 enum mem_cgroup_stat_index idx
)
114 for_each_possible_cpu(cpu
)
115 ret
+= stat
->cpustat
[cpu
].count
[idx
];
119 static s64
mem_cgroup_local_usage(struct mem_cgroup_stat
*stat
)
123 ret
= mem_cgroup_read_stat(stat
, MEM_CGROUP_STAT_CACHE
);
124 ret
+= mem_cgroup_read_stat(stat
, MEM_CGROUP_STAT_RSS
);
129 * per-zone information in memory controller.
131 struct mem_cgroup_per_zone
{
133 * spin_lock to protect the per cgroup LRU
135 struct list_head lists
[NR_LRU_LISTS
];
136 unsigned long count
[NR_LRU_LISTS
];
138 struct zone_reclaim_stat reclaim_stat
;
139 struct rb_node tree_node
; /* RB tree node */
140 unsigned long long usage_in_excess
;/* Set to the value by which */
141 /* the soft limit is exceeded*/
143 struct mem_cgroup
*mem
; /* Back pointer, we cannot */
144 /* use container_of */
146 /* Macro for accessing counter */
147 #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)])
149 struct mem_cgroup_per_node
{
150 struct mem_cgroup_per_zone zoneinfo
[MAX_NR_ZONES
];
153 struct mem_cgroup_lru_info
{
154 struct mem_cgroup_per_node
*nodeinfo
[MAX_NUMNODES
];
158 * Cgroups above their limits are maintained in a RB-Tree, independent of
159 * their hierarchy representation
162 struct mem_cgroup_tree_per_zone
{
163 struct rb_root rb_root
;
167 struct mem_cgroup_tree_per_node
{
168 struct mem_cgroup_tree_per_zone rb_tree_per_zone
[MAX_NR_ZONES
];
171 struct mem_cgroup_tree
{
172 struct mem_cgroup_tree_per_node
*rb_tree_per_node
[MAX_NUMNODES
];
175 static struct mem_cgroup_tree soft_limit_tree __read_mostly
;
178 * The memory controller data structure. The memory controller controls both
179 * page cache and RSS per cgroup. We would eventually like to provide
180 * statistics based on the statistics developed by Rik Van Riel for clock-pro,
181 * to help the administrator determine what knobs to tune.
183 * TODO: Add a water mark for the memory controller. Reclaim will begin when
184 * we hit the water mark. May be even add a low water mark, such that
185 * no reclaim occurs from a cgroup at it's low water mark, this is
186 * a feature that will be implemented much later in the future.
189 struct cgroup_subsys_state css
;
191 * the counter to account for memory usage
193 struct res_counter res
;
195 * the counter to account for mem+swap usage.
197 struct res_counter memsw
;
199 * Per cgroup active and inactive list, similar to the
200 * per zone LRU lists.
202 struct mem_cgroup_lru_info info
;
205 protect against reclaim related member.
207 spinlock_t reclaim_param_lock
;
209 int prev_priority
; /* for recording reclaim priority */
212 * While reclaiming in a hiearchy, we cache the last child we
215 int last_scanned_child
;
217 * Should the accounting and control be hierarchical, per subtree?
220 unsigned long last_oom_jiffies
;
223 unsigned int swappiness
;
225 /* set when res.limit == memsw.limit */
226 bool memsw_is_minimum
;
229 * statistics. This must be placed at the end of memcg.
231 struct mem_cgroup_stat stat
;
235 * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft
236 * limit reclaim to prevent infinite loops, if they ever occur.
238 #define MEM_CGROUP_MAX_RECLAIM_LOOPS (100)
239 #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS (2)
242 MEM_CGROUP_CHARGE_TYPE_CACHE
= 0,
243 MEM_CGROUP_CHARGE_TYPE_MAPPED
,
244 MEM_CGROUP_CHARGE_TYPE_SHMEM
, /* used by page migration of shmem */
245 MEM_CGROUP_CHARGE_TYPE_FORCE
, /* used by force_empty */
246 MEM_CGROUP_CHARGE_TYPE_SWAPOUT
, /* for accounting swapcache */
247 MEM_CGROUP_CHARGE_TYPE_DROP
, /* a page was unused swap cache */
251 /* only for here (for easy reading.) */
252 #define PCGF_CACHE (1UL << PCG_CACHE)
253 #define PCGF_USED (1UL << PCG_USED)
254 #define PCGF_LOCK (1UL << PCG_LOCK)
255 /* Not used, but added here for completeness */
256 #define PCGF_ACCT (1UL << PCG_ACCT)
258 /* for encoding cft->private value on file */
261 #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
262 #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
263 #define MEMFILE_ATTR(val) ((val) & 0xffff)
266 * Reclaim flags for mem_cgroup_hierarchical_reclaim
268 #define MEM_CGROUP_RECLAIM_NOSWAP_BIT 0x0
269 #define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT)
270 #define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1
271 #define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT)
272 #define MEM_CGROUP_RECLAIM_SOFT_BIT 0x2
273 #define MEM_CGROUP_RECLAIM_SOFT (1 << MEM_CGROUP_RECLAIM_SOFT_BIT)
275 static void mem_cgroup_get(struct mem_cgroup
*mem
);
276 static void mem_cgroup_put(struct mem_cgroup
*mem
);
277 static struct mem_cgroup
*parent_mem_cgroup(struct mem_cgroup
*mem
);
279 static struct mem_cgroup_per_zone
*
280 mem_cgroup_zoneinfo(struct mem_cgroup
*mem
, int nid
, int zid
)
282 return &mem
->info
.nodeinfo
[nid
]->zoneinfo
[zid
];
285 static struct mem_cgroup_per_zone
*
286 page_cgroup_zoneinfo(struct page_cgroup
*pc
)
288 struct mem_cgroup
*mem
= pc
->mem_cgroup
;
289 int nid
= page_cgroup_nid(pc
);
290 int zid
= page_cgroup_zid(pc
);
295 return mem_cgroup_zoneinfo(mem
, nid
, zid
);
298 static struct mem_cgroup_tree_per_zone
*
299 soft_limit_tree_node_zone(int nid
, int zid
)
301 return &soft_limit_tree
.rb_tree_per_node
[nid
]->rb_tree_per_zone
[zid
];
304 static struct mem_cgroup_tree_per_zone
*
305 soft_limit_tree_from_page(struct page
*page
)
307 int nid
= page_to_nid(page
);
308 int zid
= page_zonenum(page
);
310 return &soft_limit_tree
.rb_tree_per_node
[nid
]->rb_tree_per_zone
[zid
];
314 __mem_cgroup_insert_exceeded(struct mem_cgroup
*mem
,
315 struct mem_cgroup_per_zone
*mz
,
316 struct mem_cgroup_tree_per_zone
*mctz
,
317 unsigned long long new_usage_in_excess
)
319 struct rb_node
**p
= &mctz
->rb_root
.rb_node
;
320 struct rb_node
*parent
= NULL
;
321 struct mem_cgroup_per_zone
*mz_node
;
326 mz
->usage_in_excess
= new_usage_in_excess
;
327 if (!mz
->usage_in_excess
)
331 mz_node
= rb_entry(parent
, struct mem_cgroup_per_zone
,
333 if (mz
->usage_in_excess
< mz_node
->usage_in_excess
)
336 * We can't avoid mem cgroups that are over their soft
337 * limit by the same amount
339 else if (mz
->usage_in_excess
>= mz_node
->usage_in_excess
)
342 rb_link_node(&mz
->tree_node
, parent
, p
);
343 rb_insert_color(&mz
->tree_node
, &mctz
->rb_root
);
348 __mem_cgroup_remove_exceeded(struct mem_cgroup
*mem
,
349 struct mem_cgroup_per_zone
*mz
,
350 struct mem_cgroup_tree_per_zone
*mctz
)
354 rb_erase(&mz
->tree_node
, &mctz
->rb_root
);
359 mem_cgroup_remove_exceeded(struct mem_cgroup
*mem
,
360 struct mem_cgroup_per_zone
*mz
,
361 struct mem_cgroup_tree_per_zone
*mctz
)
363 spin_lock(&mctz
->lock
);
364 __mem_cgroup_remove_exceeded(mem
, mz
, mctz
);
365 spin_unlock(&mctz
->lock
);
368 static bool mem_cgroup_soft_limit_check(struct mem_cgroup
*mem
)
373 struct mem_cgroup_stat_cpu
*cpustat
;
376 cpustat
= &mem
->stat
.cpustat
[cpu
];
377 val
= __mem_cgroup_stat_read_local(cpustat
, MEM_CGROUP_STAT_EVENTS
);
378 if (unlikely(val
> SOFTLIMIT_EVENTS_THRESH
)) {
379 __mem_cgroup_stat_reset_safe(cpustat
, MEM_CGROUP_STAT_EVENTS
);
386 static void mem_cgroup_update_tree(struct mem_cgroup
*mem
, struct page
*page
)
388 unsigned long long excess
;
389 struct mem_cgroup_per_zone
*mz
;
390 struct mem_cgroup_tree_per_zone
*mctz
;
391 int nid
= page_to_nid(page
);
392 int zid
= page_zonenum(page
);
393 mctz
= soft_limit_tree_from_page(page
);
396 * Necessary to update all ancestors when hierarchy is used.
397 * because their event counter is not touched.
399 for (; mem
; mem
= parent_mem_cgroup(mem
)) {
400 mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
401 excess
= res_counter_soft_limit_excess(&mem
->res
);
403 * We have to update the tree if mz is on RB-tree or
404 * mem is over its softlimit.
406 if (excess
|| mz
->on_tree
) {
407 spin_lock(&mctz
->lock
);
408 /* if on-tree, remove it */
410 __mem_cgroup_remove_exceeded(mem
, mz
, mctz
);
412 * Insert again. mz->usage_in_excess will be updated.
413 * If excess is 0, no tree ops.
415 __mem_cgroup_insert_exceeded(mem
, mz
, mctz
, excess
);
416 spin_unlock(&mctz
->lock
);
421 static void mem_cgroup_remove_from_trees(struct mem_cgroup
*mem
)
424 struct mem_cgroup_per_zone
*mz
;
425 struct mem_cgroup_tree_per_zone
*mctz
;
427 for_each_node_state(node
, N_POSSIBLE
) {
428 for (zone
= 0; zone
< MAX_NR_ZONES
; zone
++) {
429 mz
= mem_cgroup_zoneinfo(mem
, node
, zone
);
430 mctz
= soft_limit_tree_node_zone(node
, zone
);
431 mem_cgroup_remove_exceeded(mem
, mz
, mctz
);
436 static inline unsigned long mem_cgroup_get_excess(struct mem_cgroup
*mem
)
438 return res_counter_soft_limit_excess(&mem
->res
) >> PAGE_SHIFT
;
441 static struct mem_cgroup_per_zone
*
442 __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone
*mctz
)
444 struct rb_node
*rightmost
= NULL
;
445 struct mem_cgroup_per_zone
*mz
;
449 rightmost
= rb_last(&mctz
->rb_root
);
451 goto done
; /* Nothing to reclaim from */
453 mz
= rb_entry(rightmost
, struct mem_cgroup_per_zone
, tree_node
);
455 * Remove the node now but someone else can add it back,
456 * we will to add it back at the end of reclaim to its correct
457 * position in the tree.
459 __mem_cgroup_remove_exceeded(mz
->mem
, mz
, mctz
);
460 if (!res_counter_soft_limit_excess(&mz
->mem
->res
) ||
461 !css_tryget(&mz
->mem
->css
))
467 static struct mem_cgroup_per_zone
*
468 mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone
*mctz
)
470 struct mem_cgroup_per_zone
*mz
;
472 spin_lock(&mctz
->lock
);
473 mz
= __mem_cgroup_largest_soft_limit_node(mctz
);
474 spin_unlock(&mctz
->lock
);
478 static void mem_cgroup_swap_statistics(struct mem_cgroup
*mem
,
481 int val
= (charge
) ? 1 : -1;
482 struct mem_cgroup_stat
*stat
= &mem
->stat
;
483 struct mem_cgroup_stat_cpu
*cpustat
;
486 cpustat
= &stat
->cpustat
[cpu
];
487 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_SWAPOUT
, val
);
491 static void mem_cgroup_charge_statistics(struct mem_cgroup
*mem
,
492 struct page_cgroup
*pc
,
495 int val
= (charge
) ? 1 : -1;
496 struct mem_cgroup_stat
*stat
= &mem
->stat
;
497 struct mem_cgroup_stat_cpu
*cpustat
;
500 cpustat
= &stat
->cpustat
[cpu
];
501 if (PageCgroupCache(pc
))
502 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_CACHE
, val
);
504 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_RSS
, val
);
507 __mem_cgroup_stat_add_safe(cpustat
,
508 MEM_CGROUP_STAT_PGPGIN_COUNT
, 1);
510 __mem_cgroup_stat_add_safe(cpustat
,
511 MEM_CGROUP_STAT_PGPGOUT_COUNT
, 1);
512 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_EVENTS
, 1);
516 static unsigned long mem_cgroup_get_local_zonestat(struct mem_cgroup
*mem
,
520 struct mem_cgroup_per_zone
*mz
;
523 for_each_online_node(nid
)
524 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
525 mz
= mem_cgroup_zoneinfo(mem
, nid
, zid
);
526 total
+= MEM_CGROUP_ZSTAT(mz
, idx
);
531 static struct mem_cgroup
*mem_cgroup_from_cont(struct cgroup
*cont
)
533 return container_of(cgroup_subsys_state(cont
,
534 mem_cgroup_subsys_id
), struct mem_cgroup
,
538 struct mem_cgroup
*mem_cgroup_from_task(struct task_struct
*p
)
541 * mm_update_next_owner() may clear mm->owner to NULL
542 * if it races with swapoff, page migration, etc.
543 * So this can be called with p == NULL.
548 return container_of(task_subsys_state(p
, mem_cgroup_subsys_id
),
549 struct mem_cgroup
, css
);
552 static struct mem_cgroup
*try_get_mem_cgroup_from_mm(struct mm_struct
*mm
)
554 struct mem_cgroup
*mem
= NULL
;
559 * Because we have no locks, mm->owner's may be being moved to other
560 * cgroup. We use css_tryget() here even if this looks
561 * pessimistic (rather than adding locks here).
565 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
568 } while (!css_tryget(&mem
->css
));
574 * Call callback function against all cgroup under hierarchy tree.
576 static int mem_cgroup_walk_tree(struct mem_cgroup
*root
, void *data
,
577 int (*func
)(struct mem_cgroup
*, void *))
579 int found
, ret
, nextid
;
580 struct cgroup_subsys_state
*css
;
581 struct mem_cgroup
*mem
;
583 if (!root
->use_hierarchy
)
584 return (*func
)(root
, data
);
592 css
= css_get_next(&mem_cgroup_subsys
, nextid
, &root
->css
,
594 if (css
&& css_tryget(css
))
595 mem
= container_of(css
, struct mem_cgroup
, css
);
599 ret
= (*func
)(mem
, data
);
603 } while (!ret
&& css
);
608 static inline bool mem_cgroup_is_root(struct mem_cgroup
*mem
)
610 return (mem
== root_mem_cgroup
);
614 * Following LRU functions are allowed to be used without PCG_LOCK.
615 * Operations are called by routine of global LRU independently from memcg.
616 * What we have to take care of here is validness of pc->mem_cgroup.
618 * Changes to pc->mem_cgroup happens when
621 * In typical case, "charge" is done before add-to-lru. Exception is SwapCache.
622 * It is added to LRU before charge.
623 * If PCG_USED bit is not set, page_cgroup is not added to this private LRU.
624 * When moving account, the page is not on LRU. It's isolated.
627 void mem_cgroup_del_lru_list(struct page
*page
, enum lru_list lru
)
629 struct page_cgroup
*pc
;
630 struct mem_cgroup_per_zone
*mz
;
632 if (mem_cgroup_disabled())
634 pc
= lookup_page_cgroup(page
);
635 /* can happen while we handle swapcache. */
636 if (!TestClearPageCgroupAcctLRU(pc
))
638 VM_BUG_ON(!pc
->mem_cgroup
);
640 * We don't check PCG_USED bit. It's cleared when the "page" is finally
641 * removed from global LRU.
643 mz
= page_cgroup_zoneinfo(pc
);
644 MEM_CGROUP_ZSTAT(mz
, lru
) -= 1;
645 if (mem_cgroup_is_root(pc
->mem_cgroup
))
647 VM_BUG_ON(list_empty(&pc
->lru
));
648 list_del_init(&pc
->lru
);
652 void mem_cgroup_del_lru(struct page
*page
)
654 mem_cgroup_del_lru_list(page
, page_lru(page
));
657 void mem_cgroup_rotate_lru_list(struct page
*page
, enum lru_list lru
)
659 struct mem_cgroup_per_zone
*mz
;
660 struct page_cgroup
*pc
;
662 if (mem_cgroup_disabled())
665 pc
= lookup_page_cgroup(page
);
667 * Used bit is set without atomic ops but after smp_wmb().
668 * For making pc->mem_cgroup visible, insert smp_rmb() here.
671 /* unused or root page is not rotated. */
672 if (!PageCgroupUsed(pc
) || mem_cgroup_is_root(pc
->mem_cgroup
))
674 mz
= page_cgroup_zoneinfo(pc
);
675 list_move(&pc
->lru
, &mz
->lists
[lru
]);
678 void mem_cgroup_add_lru_list(struct page
*page
, enum lru_list lru
)
680 struct page_cgroup
*pc
;
681 struct mem_cgroup_per_zone
*mz
;
683 if (mem_cgroup_disabled())
685 pc
= lookup_page_cgroup(page
);
686 VM_BUG_ON(PageCgroupAcctLRU(pc
));
688 * Used bit is set without atomic ops but after smp_wmb().
689 * For making pc->mem_cgroup visible, insert smp_rmb() here.
692 if (!PageCgroupUsed(pc
))
695 mz
= page_cgroup_zoneinfo(pc
);
696 MEM_CGROUP_ZSTAT(mz
, lru
) += 1;
697 SetPageCgroupAcctLRU(pc
);
698 if (mem_cgroup_is_root(pc
->mem_cgroup
))
700 list_add(&pc
->lru
, &mz
->lists
[lru
]);
704 * At handling SwapCache, pc->mem_cgroup may be changed while it's linked to
705 * lru because the page may.be reused after it's fully uncharged (because of
706 * SwapCache behavior).To handle that, unlink page_cgroup from LRU when charge
707 * it again. This function is only used to charge SwapCache. It's done under
708 * lock_page and expected that zone->lru_lock is never held.
710 static void mem_cgroup_lru_del_before_commit_swapcache(struct page
*page
)
713 struct zone
*zone
= page_zone(page
);
714 struct page_cgroup
*pc
= lookup_page_cgroup(page
);
716 spin_lock_irqsave(&zone
->lru_lock
, flags
);
718 * Forget old LRU when this page_cgroup is *not* used. This Used bit
719 * is guarded by lock_page() because the page is SwapCache.
721 if (!PageCgroupUsed(pc
))
722 mem_cgroup_del_lru_list(page
, page_lru(page
));
723 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
726 static void mem_cgroup_lru_add_after_commit_swapcache(struct page
*page
)
729 struct zone
*zone
= page_zone(page
);
730 struct page_cgroup
*pc
= lookup_page_cgroup(page
);
732 spin_lock_irqsave(&zone
->lru_lock
, flags
);
733 /* link when the page is linked to LRU but page_cgroup isn't */
734 if (PageLRU(page
) && !PageCgroupAcctLRU(pc
))
735 mem_cgroup_add_lru_list(page
, page_lru(page
));
736 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
740 void mem_cgroup_move_lists(struct page
*page
,
741 enum lru_list from
, enum lru_list to
)
743 if (mem_cgroup_disabled())
745 mem_cgroup_del_lru_list(page
, from
);
746 mem_cgroup_add_lru_list(page
, to
);
749 int task_in_mem_cgroup(struct task_struct
*task
, const struct mem_cgroup
*mem
)
752 struct mem_cgroup
*curr
= NULL
;
756 curr
= try_get_mem_cgroup_from_mm(task
->mm
);
761 if (curr
->use_hierarchy
)
762 ret
= css_is_ancestor(&curr
->css
, &mem
->css
);
770 * prev_priority control...this will be used in memory reclaim path.
772 int mem_cgroup_get_reclaim_priority(struct mem_cgroup
*mem
)
776 spin_lock(&mem
->reclaim_param_lock
);
777 prev_priority
= mem
->prev_priority
;
778 spin_unlock(&mem
->reclaim_param_lock
);
780 return prev_priority
;
783 void mem_cgroup_note_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
785 spin_lock(&mem
->reclaim_param_lock
);
786 if (priority
< mem
->prev_priority
)
787 mem
->prev_priority
= priority
;
788 spin_unlock(&mem
->reclaim_param_lock
);
791 void mem_cgroup_record_reclaim_priority(struct mem_cgroup
*mem
, int priority
)
793 spin_lock(&mem
->reclaim_param_lock
);
794 mem
->prev_priority
= priority
;
795 spin_unlock(&mem
->reclaim_param_lock
);
798 static int calc_inactive_ratio(struct mem_cgroup
*memcg
, unsigned long *present_pages
)
800 unsigned long active
;
801 unsigned long inactive
;
803 unsigned long inactive_ratio
;
805 inactive
= mem_cgroup_get_local_zonestat(memcg
, LRU_INACTIVE_ANON
);
806 active
= mem_cgroup_get_local_zonestat(memcg
, LRU_ACTIVE_ANON
);
808 gb
= (inactive
+ active
) >> (30 - PAGE_SHIFT
);
810 inactive_ratio
= int_sqrt(10 * gb
);
815 present_pages
[0] = inactive
;
816 present_pages
[1] = active
;
819 return inactive_ratio
;
822 int mem_cgroup_inactive_anon_is_low(struct mem_cgroup
*memcg
)
824 unsigned long active
;
825 unsigned long inactive
;
826 unsigned long present_pages
[2];
827 unsigned long inactive_ratio
;
829 inactive_ratio
= calc_inactive_ratio(memcg
, present_pages
);
831 inactive
= present_pages
[0];
832 active
= present_pages
[1];
834 if (inactive
* inactive_ratio
< active
)
840 int mem_cgroup_inactive_file_is_low(struct mem_cgroup
*memcg
)
842 unsigned long active
;
843 unsigned long inactive
;
845 inactive
= mem_cgroup_get_local_zonestat(memcg
, LRU_INACTIVE_FILE
);
846 active
= mem_cgroup_get_local_zonestat(memcg
, LRU_ACTIVE_FILE
);
848 return (active
> inactive
);
851 unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup
*memcg
,
855 int nid
= zone
->zone_pgdat
->node_id
;
856 int zid
= zone_idx(zone
);
857 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(memcg
, nid
, zid
);
859 return MEM_CGROUP_ZSTAT(mz
, lru
);
862 struct zone_reclaim_stat
*mem_cgroup_get_reclaim_stat(struct mem_cgroup
*memcg
,
865 int nid
= zone
->zone_pgdat
->node_id
;
866 int zid
= zone_idx(zone
);
867 struct mem_cgroup_per_zone
*mz
= mem_cgroup_zoneinfo(memcg
, nid
, zid
);
869 return &mz
->reclaim_stat
;
872 struct zone_reclaim_stat
*
873 mem_cgroup_get_reclaim_stat_from_page(struct page
*page
)
875 struct page_cgroup
*pc
;
876 struct mem_cgroup_per_zone
*mz
;
878 if (mem_cgroup_disabled())
881 pc
= lookup_page_cgroup(page
);
883 * Used bit is set without atomic ops but after smp_wmb().
884 * For making pc->mem_cgroup visible, insert smp_rmb() here.
887 if (!PageCgroupUsed(pc
))
890 mz
= page_cgroup_zoneinfo(pc
);
894 return &mz
->reclaim_stat
;
897 unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan
,
898 struct list_head
*dst
,
899 unsigned long *scanned
, int order
,
900 int mode
, struct zone
*z
,
901 struct mem_cgroup
*mem_cont
,
902 int active
, int file
)
904 unsigned long nr_taken
= 0;
908 struct list_head
*src
;
909 struct page_cgroup
*pc
, *tmp
;
910 int nid
= z
->zone_pgdat
->node_id
;
911 int zid
= zone_idx(z
);
912 struct mem_cgroup_per_zone
*mz
;
913 int lru
= LRU_FILE
* file
+ active
;
917 mz
= mem_cgroup_zoneinfo(mem_cont
, nid
, zid
);
918 src
= &mz
->lists
[lru
];
921 list_for_each_entry_safe_reverse(pc
, tmp
, src
, lru
) {
922 if (scan
>= nr_to_scan
)
926 if (unlikely(!PageCgroupUsed(pc
)))
928 if (unlikely(!PageLRU(page
)))
932 ret
= __isolate_lru_page(page
, mode
, file
);
935 list_move(&page
->lru
, dst
);
936 mem_cgroup_del_lru(page
);
940 /* we don't affect global LRU but rotate in our LRU */
941 mem_cgroup_rotate_lru_list(page
, page_lru(page
));
952 #define mem_cgroup_from_res_counter(counter, member) \
953 container_of(counter, struct mem_cgroup, member)
955 static bool mem_cgroup_check_under_limit(struct mem_cgroup
*mem
)
957 if (do_swap_account
) {
958 if (res_counter_check_under_limit(&mem
->res
) &&
959 res_counter_check_under_limit(&mem
->memsw
))
962 if (res_counter_check_under_limit(&mem
->res
))
967 static unsigned int get_swappiness(struct mem_cgroup
*memcg
)
969 struct cgroup
*cgrp
= memcg
->css
.cgroup
;
970 unsigned int swappiness
;
973 if (cgrp
->parent
== NULL
)
974 return vm_swappiness
;
976 spin_lock(&memcg
->reclaim_param_lock
);
977 swappiness
= memcg
->swappiness
;
978 spin_unlock(&memcg
->reclaim_param_lock
);
983 static int mem_cgroup_count_children_cb(struct mem_cgroup
*mem
, void *data
)
991 * mem_cgroup_print_mem_info: Called from OOM with tasklist_lock held in read mode.
992 * @memcg: The memory cgroup that went over limit
993 * @p: Task that is going to be killed
995 * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is
998 void mem_cgroup_print_oom_info(struct mem_cgroup
*memcg
, struct task_struct
*p
)
1000 struct cgroup
*task_cgrp
;
1001 struct cgroup
*mem_cgrp
;
1003 * Need a buffer in BSS, can't rely on allocations. The code relies
1004 * on the assumption that OOM is serialized for memory controller.
1005 * If this assumption is broken, revisit this code.
1007 static char memcg_name
[PATH_MAX
];
1016 mem_cgrp
= memcg
->css
.cgroup
;
1017 task_cgrp
= task_cgroup(p
, mem_cgroup_subsys_id
);
1019 ret
= cgroup_path(task_cgrp
, memcg_name
, PATH_MAX
);
1022 * Unfortunately, we are unable to convert to a useful name
1023 * But we'll still print out the usage information
1030 printk(KERN_INFO
"Task in %s killed", memcg_name
);
1033 ret
= cgroup_path(mem_cgrp
, memcg_name
, PATH_MAX
);
1041 * Continues from above, so we don't need an KERN_ level
1043 printk(KERN_CONT
" as a result of limit of %s\n", memcg_name
);
1046 printk(KERN_INFO
"memory: usage %llukB, limit %llukB, failcnt %llu\n",
1047 res_counter_read_u64(&memcg
->res
, RES_USAGE
) >> 10,
1048 res_counter_read_u64(&memcg
->res
, RES_LIMIT
) >> 10,
1049 res_counter_read_u64(&memcg
->res
, RES_FAILCNT
));
1050 printk(KERN_INFO
"memory+swap: usage %llukB, limit %llukB, "
1052 res_counter_read_u64(&memcg
->memsw
, RES_USAGE
) >> 10,
1053 res_counter_read_u64(&memcg
->memsw
, RES_LIMIT
) >> 10,
1054 res_counter_read_u64(&memcg
->memsw
, RES_FAILCNT
));
1058 * This function returns the number of memcg under hierarchy tree. Returns
1059 * 1(self count) if no children.
1061 static int mem_cgroup_count_children(struct mem_cgroup
*mem
)
1064 mem_cgroup_walk_tree(mem
, &num
, mem_cgroup_count_children_cb
);
1069 * Visit the first child (need not be the first child as per the ordering
1070 * of the cgroup list, since we track last_scanned_child) of @mem and use
1071 * that to reclaim free pages from.
1073 static struct mem_cgroup
*
1074 mem_cgroup_select_victim(struct mem_cgroup
*root_mem
)
1076 struct mem_cgroup
*ret
= NULL
;
1077 struct cgroup_subsys_state
*css
;
1080 if (!root_mem
->use_hierarchy
) {
1081 css_get(&root_mem
->css
);
1087 nextid
= root_mem
->last_scanned_child
+ 1;
1088 css
= css_get_next(&mem_cgroup_subsys
, nextid
, &root_mem
->css
,
1090 if (css
&& css_tryget(css
))
1091 ret
= container_of(css
, struct mem_cgroup
, css
);
1094 /* Updates scanning parameter */
1095 spin_lock(&root_mem
->reclaim_param_lock
);
1097 /* this means start scan from ID:1 */
1098 root_mem
->last_scanned_child
= 0;
1100 root_mem
->last_scanned_child
= found
;
1101 spin_unlock(&root_mem
->reclaim_param_lock
);
1108 * Scan the hierarchy if needed to reclaim memory. We remember the last child
1109 * we reclaimed from, so that we don't end up penalizing one child extensively
1110 * based on its position in the children list.
1112 * root_mem is the original ancestor that we've been reclaim from.
1114 * We give up and return to the caller when we visit root_mem twice.
1115 * (other groups can be removed while we're walking....)
1117 * If shrink==true, for avoiding to free too much, this returns immedieately.
1119 static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup
*root_mem
,
1122 unsigned long reclaim_options
)
1124 struct mem_cgroup
*victim
;
1127 bool noswap
= reclaim_options
& MEM_CGROUP_RECLAIM_NOSWAP
;
1128 bool shrink
= reclaim_options
& MEM_CGROUP_RECLAIM_SHRINK
;
1129 bool check_soft
= reclaim_options
& MEM_CGROUP_RECLAIM_SOFT
;
1130 unsigned long excess
= mem_cgroup_get_excess(root_mem
);
1132 /* If memsw_is_minimum==1, swap-out is of-no-use. */
1133 if (root_mem
->memsw_is_minimum
)
1137 victim
= mem_cgroup_select_victim(root_mem
);
1138 if (victim
== root_mem
) {
1142 * If we have not been able to reclaim
1143 * anything, it might because there are
1144 * no reclaimable pages under this hierarchy
1146 if (!check_soft
|| !total
) {
1147 css_put(&victim
->css
);
1151 * We want to do more targetted reclaim.
1152 * excess >> 2 is not to excessive so as to
1153 * reclaim too much, nor too less that we keep
1154 * coming back to reclaim from this cgroup
1156 if (total
>= (excess
>> 2) ||
1157 (loop
> MEM_CGROUP_MAX_RECLAIM_LOOPS
)) {
1158 css_put(&victim
->css
);
1163 if (!mem_cgroup_local_usage(&victim
->stat
)) {
1164 /* this cgroup's local usage == 0 */
1165 css_put(&victim
->css
);
1168 /* we use swappiness of local cgroup */
1170 ret
= mem_cgroup_shrink_node_zone(victim
, gfp_mask
,
1171 noswap
, get_swappiness(victim
), zone
,
1172 zone
->zone_pgdat
->node_id
);
1174 ret
= try_to_free_mem_cgroup_pages(victim
, gfp_mask
,
1175 noswap
, get_swappiness(victim
));
1176 css_put(&victim
->css
);
1178 * At shrinking usage, we can't check we should stop here or
1179 * reclaim more. It's depends on callers. last_scanned_child
1180 * will work enough for keeping fairness under tree.
1186 if (res_counter_check_under_soft_limit(&root_mem
->res
))
1188 } else if (mem_cgroup_check_under_limit(root_mem
))
1194 bool mem_cgroup_oom_called(struct task_struct
*task
)
1197 struct mem_cgroup
*mem
;
1198 struct mm_struct
*mm
;
1204 mem
= mem_cgroup_from_task(rcu_dereference(mm
->owner
));
1205 if (mem
&& time_before(jiffies
, mem
->last_oom_jiffies
+ HZ
/10))
1211 static int record_last_oom_cb(struct mem_cgroup
*mem
, void *data
)
1213 mem
->last_oom_jiffies
= jiffies
;
1217 static void record_last_oom(struct mem_cgroup
*mem
)
1219 mem_cgroup_walk_tree(mem
, NULL
, record_last_oom_cb
);
1223 * Currently used to update mapped file statistics, but the routine can be
1224 * generalized to update other statistics as well.
1226 void mem_cgroup_update_mapped_file_stat(struct page
*page
, int val
)
1228 struct mem_cgroup
*mem
;
1229 struct mem_cgroup_stat
*stat
;
1230 struct mem_cgroup_stat_cpu
*cpustat
;
1232 struct page_cgroup
*pc
;
1234 if (!page_is_file_cache(page
))
1237 pc
= lookup_page_cgroup(page
);
1241 lock_page_cgroup(pc
);
1242 mem
= pc
->mem_cgroup
;
1246 if (!PageCgroupUsed(pc
))
1250 * Preemption is already disabled, we don't need get_cpu()
1252 cpu
= smp_processor_id();
1254 cpustat
= &stat
->cpustat
[cpu
];
1256 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_MAPPED_FILE
, val
);
1258 unlock_page_cgroup(pc
);
1262 * Unlike exported interface, "oom" parameter is added. if oom==true,
1263 * oom-killer can be invoked.
1265 static int __mem_cgroup_try_charge(struct mm_struct
*mm
,
1266 gfp_t gfp_mask
, struct mem_cgroup
**memcg
,
1267 bool oom
, struct page
*page
)
1269 struct mem_cgroup
*mem
, *mem_over_limit
;
1270 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
1271 struct res_counter
*fail_res
;
1273 if (unlikely(test_thread_flag(TIF_MEMDIE
))) {
1274 /* Don't account this! */
1280 * We always charge the cgroup the mm_struct belongs to.
1281 * The mm_struct's mem_cgroup changes on task migration if the
1282 * thread group leader migrates. It's possible that mm is not
1283 * set, if so charge the init_mm (happens for pagecache usage).
1287 mem
= try_get_mem_cgroup_from_mm(mm
);
1295 VM_BUG_ON(css_is_removed(&mem
->css
));
1299 unsigned long flags
= 0;
1301 if (mem_cgroup_is_root(mem
))
1303 ret
= res_counter_charge(&mem
->res
, PAGE_SIZE
, &fail_res
);
1305 if (!do_swap_account
)
1307 ret
= res_counter_charge(&mem
->memsw
, PAGE_SIZE
,
1311 /* mem+swap counter fails */
1312 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1313 flags
|= MEM_CGROUP_RECLAIM_NOSWAP
;
1314 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
1317 /* mem counter fails */
1318 mem_over_limit
= mem_cgroup_from_res_counter(fail_res
,
1321 if (!(gfp_mask
& __GFP_WAIT
))
1324 ret
= mem_cgroup_hierarchical_reclaim(mem_over_limit
, NULL
,
1330 * try_to_free_mem_cgroup_pages() might not give us a full
1331 * picture of reclaim. Some pages are reclaimed and might be
1332 * moved to swap cache or just unmapped from the cgroup.
1333 * Check the limit again to see if the reclaim reduced the
1334 * current usage of the cgroup before giving up
1337 if (mem_cgroup_check_under_limit(mem_over_limit
))
1340 if (!nr_retries
--) {
1342 mutex_lock(&memcg_tasklist
);
1343 mem_cgroup_out_of_memory(mem_over_limit
, gfp_mask
);
1344 mutex_unlock(&memcg_tasklist
);
1345 record_last_oom(mem_over_limit
);
1351 * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree.
1352 * if they exceeds softlimit.
1354 if (mem_cgroup_soft_limit_check(mem
))
1355 mem_cgroup_update_tree(mem
, page
);
1364 * A helper function to get mem_cgroup from ID. must be called under
1365 * rcu_read_lock(). The caller must check css_is_removed() or some if
1366 * it's concern. (dropping refcnt from swap can be called against removed
1369 static struct mem_cgroup
*mem_cgroup_lookup(unsigned short id
)
1371 struct cgroup_subsys_state
*css
;
1373 /* ID 0 is unused ID */
1376 css
= css_lookup(&mem_cgroup_subsys
, id
);
1379 return container_of(css
, struct mem_cgroup
, css
);
1382 static struct mem_cgroup
*try_get_mem_cgroup_from_swapcache(struct page
*page
)
1384 struct mem_cgroup
*mem
;
1385 struct page_cgroup
*pc
;
1389 VM_BUG_ON(!PageLocked(page
));
1391 if (!PageSwapCache(page
))
1394 pc
= lookup_page_cgroup(page
);
1395 lock_page_cgroup(pc
);
1396 if (PageCgroupUsed(pc
)) {
1397 mem
= pc
->mem_cgroup
;
1398 if (mem
&& !css_tryget(&mem
->css
))
1401 ent
.val
= page_private(page
);
1402 id
= lookup_swap_cgroup(ent
);
1404 mem
= mem_cgroup_lookup(id
);
1405 if (mem
&& !css_tryget(&mem
->css
))
1409 unlock_page_cgroup(pc
);
1414 * commit a charge got by __mem_cgroup_try_charge() and makes page_cgroup to be
1415 * USED state. If already USED, uncharge and return.
1418 static void __mem_cgroup_commit_charge(struct mem_cgroup
*mem
,
1419 struct page_cgroup
*pc
,
1420 enum charge_type ctype
)
1422 /* try_charge() can return NULL to *memcg, taking care of it. */
1426 lock_page_cgroup(pc
);
1427 if (unlikely(PageCgroupUsed(pc
))) {
1428 unlock_page_cgroup(pc
);
1429 if (!mem_cgroup_is_root(mem
)) {
1430 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1431 if (do_swap_account
)
1432 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1438 pc
->mem_cgroup
= mem
;
1440 * We access a page_cgroup asynchronously without lock_page_cgroup().
1441 * Especially when a page_cgroup is taken from a page, pc->mem_cgroup
1442 * is accessed after testing USED bit. To make pc->mem_cgroup visible
1443 * before USED bit, we need memory barrier here.
1444 * See mem_cgroup_add_lru_list(), etc.
1448 case MEM_CGROUP_CHARGE_TYPE_CACHE
:
1449 case MEM_CGROUP_CHARGE_TYPE_SHMEM
:
1450 SetPageCgroupCache(pc
);
1451 SetPageCgroupUsed(pc
);
1453 case MEM_CGROUP_CHARGE_TYPE_MAPPED
:
1454 ClearPageCgroupCache(pc
);
1455 SetPageCgroupUsed(pc
);
1461 mem_cgroup_charge_statistics(mem
, pc
, true);
1463 unlock_page_cgroup(pc
);
1467 * mem_cgroup_move_account - move account of the page
1468 * @pc: page_cgroup of the page.
1469 * @from: mem_cgroup which the page is moved from.
1470 * @to: mem_cgroup which the page is moved to. @from != @to.
1472 * The caller must confirm following.
1473 * - page is not on LRU (isolate_page() is useful.)
1475 * returns 0 at success,
1476 * returns -EBUSY when lock is busy or "pc" is unstable.
1478 * This function does "uncharge" from old cgroup but doesn't do "charge" to
1479 * new cgroup. It should be done by a caller.
1482 static int mem_cgroup_move_account(struct page_cgroup
*pc
,
1483 struct mem_cgroup
*from
, struct mem_cgroup
*to
)
1485 struct mem_cgroup_per_zone
*from_mz
, *to_mz
;
1490 struct mem_cgroup_stat
*stat
;
1491 struct mem_cgroup_stat_cpu
*cpustat
;
1493 VM_BUG_ON(from
== to
);
1494 VM_BUG_ON(PageLRU(pc
->page
));
1496 nid
= page_cgroup_nid(pc
);
1497 zid
= page_cgroup_zid(pc
);
1498 from_mz
= mem_cgroup_zoneinfo(from
, nid
, zid
);
1499 to_mz
= mem_cgroup_zoneinfo(to
, nid
, zid
);
1501 if (!trylock_page_cgroup(pc
))
1504 if (!PageCgroupUsed(pc
))
1507 if (pc
->mem_cgroup
!= from
)
1510 if (!mem_cgroup_is_root(from
))
1511 res_counter_uncharge(&from
->res
, PAGE_SIZE
);
1512 mem_cgroup_charge_statistics(from
, pc
, false);
1515 if (page_is_file_cache(page
) && page_mapped(page
)) {
1516 cpu
= smp_processor_id();
1517 /* Update mapped_file data for mem_cgroup "from" */
1519 cpustat
= &stat
->cpustat
[cpu
];
1520 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_MAPPED_FILE
,
1523 /* Update mapped_file data for mem_cgroup "to" */
1525 cpustat
= &stat
->cpustat
[cpu
];
1526 __mem_cgroup_stat_add_safe(cpustat
, MEM_CGROUP_STAT_MAPPED_FILE
,
1530 if (do_swap_account
&& !mem_cgroup_is_root(from
))
1531 res_counter_uncharge(&from
->memsw
, PAGE_SIZE
);
1532 css_put(&from
->css
);
1535 pc
->mem_cgroup
= to
;
1536 mem_cgroup_charge_statistics(to
, pc
, true);
1539 unlock_page_cgroup(pc
);
1541 * We charges against "to" which may not have any tasks. Then, "to"
1542 * can be under rmdir(). But in current implementation, caller of
1543 * this function is just force_empty() and it's garanteed that
1544 * "to" is never removed. So, we don't check rmdir status here.
1550 * move charges to its parent.
1553 static int mem_cgroup_move_parent(struct page_cgroup
*pc
,
1554 struct mem_cgroup
*child
,
1557 struct page
*page
= pc
->page
;
1558 struct cgroup
*cg
= child
->css
.cgroup
;
1559 struct cgroup
*pcg
= cg
->parent
;
1560 struct mem_cgroup
*parent
;
1568 parent
= mem_cgroup_from_cont(pcg
);
1571 ret
= __mem_cgroup_try_charge(NULL
, gfp_mask
, &parent
, false, page
);
1575 if (!get_page_unless_zero(page
)) {
1580 ret
= isolate_lru_page(page
);
1585 ret
= mem_cgroup_move_account(pc
, child
, parent
);
1587 putback_lru_page(page
);
1590 /* drop extra refcnt by try_charge() */
1591 css_put(&parent
->css
);
1598 /* drop extra refcnt by try_charge() */
1599 css_put(&parent
->css
);
1600 /* uncharge if move fails */
1601 if (!mem_cgroup_is_root(parent
)) {
1602 res_counter_uncharge(&parent
->res
, PAGE_SIZE
);
1603 if (do_swap_account
)
1604 res_counter_uncharge(&parent
->memsw
, PAGE_SIZE
);
1610 * Charge the memory controller for page usage.
1612 * 0 if the charge was successful
1613 * < 0 if the cgroup is over its limit
1615 static int mem_cgroup_charge_common(struct page
*page
, struct mm_struct
*mm
,
1616 gfp_t gfp_mask
, enum charge_type ctype
,
1617 struct mem_cgroup
*memcg
)
1619 struct mem_cgroup
*mem
;
1620 struct page_cgroup
*pc
;
1623 pc
= lookup_page_cgroup(page
);
1624 /* can happen at boot */
1630 ret
= __mem_cgroup_try_charge(mm
, gfp_mask
, &mem
, true, page
);
1634 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
1638 int mem_cgroup_newpage_charge(struct page
*page
,
1639 struct mm_struct
*mm
, gfp_t gfp_mask
)
1641 if (mem_cgroup_disabled())
1643 if (PageCompound(page
))
1646 * If already mapped, we don't have to account.
1647 * If page cache, page->mapping has address_space.
1648 * But page->mapping may have out-of-use anon_vma pointer,
1649 * detecit it by PageAnon() check. newly-mapped-anon's page->mapping
1652 if (page_mapped(page
) || (page
->mapping
&& !PageAnon(page
)))
1656 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1657 MEM_CGROUP_CHARGE_TYPE_MAPPED
, NULL
);
1661 __mem_cgroup_commit_charge_swapin(struct page
*page
, struct mem_cgroup
*ptr
,
1662 enum charge_type ctype
);
1664 int mem_cgroup_cache_charge(struct page
*page
, struct mm_struct
*mm
,
1667 struct mem_cgroup
*mem
= NULL
;
1670 if (mem_cgroup_disabled())
1672 if (PageCompound(page
))
1675 * Corner case handling. This is called from add_to_page_cache()
1676 * in usual. But some FS (shmem) precharges this page before calling it
1677 * and call add_to_page_cache() with GFP_NOWAIT.
1679 * For GFP_NOWAIT case, the page may be pre-charged before calling
1680 * add_to_page_cache(). (See shmem.c) check it here and avoid to call
1681 * charge twice. (It works but has to pay a bit larger cost.)
1682 * And when the page is SwapCache, it should take swap information
1683 * into account. This is under lock_page() now.
1685 if (!(gfp_mask
& __GFP_WAIT
)) {
1686 struct page_cgroup
*pc
;
1689 pc
= lookup_page_cgroup(page
);
1692 lock_page_cgroup(pc
);
1693 if (PageCgroupUsed(pc
)) {
1694 unlock_page_cgroup(pc
);
1697 unlock_page_cgroup(pc
);
1700 if (unlikely(!mm
&& !mem
))
1703 if (page_is_file_cache(page
))
1704 return mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1705 MEM_CGROUP_CHARGE_TYPE_CACHE
, NULL
);
1708 if (PageSwapCache(page
)) {
1709 ret
= mem_cgroup_try_charge_swapin(mm
, page
, gfp_mask
, &mem
);
1711 __mem_cgroup_commit_charge_swapin(page
, mem
,
1712 MEM_CGROUP_CHARGE_TYPE_SHMEM
);
1714 ret
= mem_cgroup_charge_common(page
, mm
, gfp_mask
,
1715 MEM_CGROUP_CHARGE_TYPE_SHMEM
, mem
);
1721 * While swap-in, try_charge -> commit or cancel, the page is locked.
1722 * And when try_charge() successfully returns, one refcnt to memcg without
1723 * struct page_cgroup is aquired. This refcnt will be cumsumed by
1724 * "commit()" or removed by "cancel()"
1726 int mem_cgroup_try_charge_swapin(struct mm_struct
*mm
,
1728 gfp_t mask
, struct mem_cgroup
**ptr
)
1730 struct mem_cgroup
*mem
;
1733 if (mem_cgroup_disabled())
1736 if (!do_swap_account
)
1739 * A racing thread's fault, or swapoff, may have already updated
1740 * the pte, and even removed page from swap cache: return success
1741 * to go on to do_swap_page()'s pte_same() test, which should fail.
1743 if (!PageSwapCache(page
))
1745 mem
= try_get_mem_cgroup_from_swapcache(page
);
1749 ret
= __mem_cgroup_try_charge(NULL
, mask
, ptr
, true, page
);
1750 /* drop extra refcnt from tryget */
1756 return __mem_cgroup_try_charge(mm
, mask
, ptr
, true, page
);
1760 __mem_cgroup_commit_charge_swapin(struct page
*page
, struct mem_cgroup
*ptr
,
1761 enum charge_type ctype
)
1763 struct page_cgroup
*pc
;
1765 if (mem_cgroup_disabled())
1769 cgroup_exclude_rmdir(&ptr
->css
);
1770 pc
= lookup_page_cgroup(page
);
1771 mem_cgroup_lru_del_before_commit_swapcache(page
);
1772 __mem_cgroup_commit_charge(ptr
, pc
, ctype
);
1773 mem_cgroup_lru_add_after_commit_swapcache(page
);
1775 * Now swap is on-memory. This means this page may be
1776 * counted both as mem and swap....double count.
1777 * Fix it by uncharging from memsw. Basically, this SwapCache is stable
1778 * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page()
1779 * may call delete_from_swap_cache() before reach here.
1781 if (do_swap_account
&& PageSwapCache(page
)) {
1782 swp_entry_t ent
= {.val
= page_private(page
)};
1784 struct mem_cgroup
*memcg
;
1786 id
= swap_cgroup_record(ent
, 0);
1788 memcg
= mem_cgroup_lookup(id
);
1791 * This recorded memcg can be obsolete one. So, avoid
1792 * calling css_tryget
1794 if (!mem_cgroup_is_root(memcg
))
1795 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1796 mem_cgroup_swap_statistics(memcg
, false);
1797 mem_cgroup_put(memcg
);
1802 * At swapin, we may charge account against cgroup which has no tasks.
1803 * So, rmdir()->pre_destroy() can be called while we do this charge.
1804 * In that case, we need to call pre_destroy() again. check it here.
1806 cgroup_release_and_wakeup_rmdir(&ptr
->css
);
1809 void mem_cgroup_commit_charge_swapin(struct page
*page
, struct mem_cgroup
*ptr
)
1811 __mem_cgroup_commit_charge_swapin(page
, ptr
,
1812 MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1815 void mem_cgroup_cancel_charge_swapin(struct mem_cgroup
*mem
)
1817 if (mem_cgroup_disabled())
1821 if (!mem_cgroup_is_root(mem
)) {
1822 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1823 if (do_swap_account
)
1824 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1831 * uncharge if !page_mapped(page)
1833 static struct mem_cgroup
*
1834 __mem_cgroup_uncharge_common(struct page
*page
, enum charge_type ctype
)
1836 struct page_cgroup
*pc
;
1837 struct mem_cgroup
*mem
= NULL
;
1838 struct mem_cgroup_per_zone
*mz
;
1840 if (mem_cgroup_disabled())
1843 if (PageSwapCache(page
))
1847 * Check if our page_cgroup is valid
1849 pc
= lookup_page_cgroup(page
);
1850 if (unlikely(!pc
|| !PageCgroupUsed(pc
)))
1853 lock_page_cgroup(pc
);
1855 mem
= pc
->mem_cgroup
;
1857 if (!PageCgroupUsed(pc
))
1861 case MEM_CGROUP_CHARGE_TYPE_MAPPED
:
1862 case MEM_CGROUP_CHARGE_TYPE_DROP
:
1863 if (page_mapped(page
))
1866 case MEM_CGROUP_CHARGE_TYPE_SWAPOUT
:
1867 if (!PageAnon(page
)) { /* Shared memory */
1868 if (page
->mapping
&& !page_is_file_cache(page
))
1870 } else if (page_mapped(page
)) /* Anon */
1877 if (!mem_cgroup_is_root(mem
)) {
1878 res_counter_uncharge(&mem
->res
, PAGE_SIZE
);
1879 if (do_swap_account
&&
1880 (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
))
1881 res_counter_uncharge(&mem
->memsw
, PAGE_SIZE
);
1883 if (ctype
== MEM_CGROUP_CHARGE_TYPE_SWAPOUT
)
1884 mem_cgroup_swap_statistics(mem
, true);
1885 mem_cgroup_charge_statistics(mem
, pc
, false);
1887 ClearPageCgroupUsed(pc
);
1889 * pc->mem_cgroup is not cleared here. It will be accessed when it's
1890 * freed from LRU. This is safe because uncharged page is expected not
1891 * to be reused (freed soon). Exception is SwapCache, it's handled by
1892 * special functions.
1895 mz
= page_cgroup_zoneinfo(pc
);
1896 unlock_page_cgroup(pc
);
1898 if (mem_cgroup_soft_limit_check(mem
))
1899 mem_cgroup_update_tree(mem
, page
);
1900 /* at swapout, this memcg will be accessed to record to swap */
1901 if (ctype
!= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
)
1907 unlock_page_cgroup(pc
);
1911 void mem_cgroup_uncharge_page(struct page
*page
)
1914 if (page_mapped(page
))
1916 if (page
->mapping
&& !PageAnon(page
))
1918 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_MAPPED
);
1921 void mem_cgroup_uncharge_cache_page(struct page
*page
)
1923 VM_BUG_ON(page_mapped(page
));
1924 VM_BUG_ON(page
->mapping
);
1925 __mem_cgroup_uncharge_common(page
, MEM_CGROUP_CHARGE_TYPE_CACHE
);
1930 * called after __delete_from_swap_cache() and drop "page" account.
1931 * memcg information is recorded to swap_cgroup of "ent"
1934 mem_cgroup_uncharge_swapcache(struct page
*page
, swp_entry_t ent
, bool swapout
)
1936 struct mem_cgroup
*memcg
;
1937 int ctype
= MEM_CGROUP_CHARGE_TYPE_SWAPOUT
;
1939 if (!swapout
) /* this was a swap cache but the swap is unused ! */
1940 ctype
= MEM_CGROUP_CHARGE_TYPE_DROP
;
1942 memcg
= __mem_cgroup_uncharge_common(page
, ctype
);
1944 /* record memcg information */
1945 if (do_swap_account
&& swapout
&& memcg
) {
1946 swap_cgroup_record(ent
, css_id(&memcg
->css
));
1947 mem_cgroup_get(memcg
);
1949 if (swapout
&& memcg
)
1950 css_put(&memcg
->css
);
1954 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1956 * called from swap_entry_free(). remove record in swap_cgroup and
1957 * uncharge "memsw" account.
1959 void mem_cgroup_uncharge_swap(swp_entry_t ent
)
1961 struct mem_cgroup
*memcg
;
1964 if (!do_swap_account
)
1967 id
= swap_cgroup_record(ent
, 0);
1969 memcg
= mem_cgroup_lookup(id
);
1972 * We uncharge this because swap is freed.
1973 * This memcg can be obsolete one. We avoid calling css_tryget
1975 if (!mem_cgroup_is_root(memcg
))
1976 res_counter_uncharge(&memcg
->memsw
, PAGE_SIZE
);
1977 mem_cgroup_swap_statistics(memcg
, false);
1978 mem_cgroup_put(memcg
);
1985 * Before starting migration, account PAGE_SIZE to mem_cgroup that the old
1988 int mem_cgroup_prepare_migration(struct page
*page
, struct mem_cgroup
**ptr
)
1990 struct page_cgroup
*pc
;
1991 struct mem_cgroup
*mem
= NULL
;
1994 if (mem_cgroup_disabled())
1997 pc
= lookup_page_cgroup(page
);
1998 lock_page_cgroup(pc
);
1999 if (PageCgroupUsed(pc
)) {
2000 mem
= pc
->mem_cgroup
;
2003 unlock_page_cgroup(pc
);
2006 ret
= __mem_cgroup_try_charge(NULL
, GFP_KERNEL
, &mem
, false,
2014 /* remove redundant charge if migration failed*/
2015 void mem_cgroup_end_migration(struct mem_cgroup
*mem
,
2016 struct page
*oldpage
, struct page
*newpage
)
2018 struct page
*target
, *unused
;
2019 struct page_cgroup
*pc
;
2020 enum charge_type ctype
;
2024 cgroup_exclude_rmdir(&mem
->css
);
2025 /* at migration success, oldpage->mapping is NULL. */
2026 if (oldpage
->mapping
) {
2034 if (PageAnon(target
))
2035 ctype
= MEM_CGROUP_CHARGE_TYPE_MAPPED
;
2036 else if (page_is_file_cache(target
))
2037 ctype
= MEM_CGROUP_CHARGE_TYPE_CACHE
;
2039 ctype
= MEM_CGROUP_CHARGE_TYPE_SHMEM
;
2041 /* unused page is not on radix-tree now. */
2043 __mem_cgroup_uncharge_common(unused
, ctype
);
2045 pc
= lookup_page_cgroup(target
);
2047 * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
2048 * So, double-counting is effectively avoided.
2050 __mem_cgroup_commit_charge(mem
, pc
, ctype
);
2053 * Both of oldpage and newpage are still under lock_page().
2054 * Then, we don't have to care about race in radix-tree.
2055 * But we have to be careful that this page is unmapped or not.
2057 * There is a case for !page_mapped(). At the start of
2058 * migration, oldpage was mapped. But now, it's zapped.
2059 * But we know *target* page is not freed/reused under us.
2060 * mem_cgroup_uncharge_page() does all necessary checks.
2062 if (ctype
== MEM_CGROUP_CHARGE_TYPE_MAPPED
)
2063 mem_cgroup_uncharge_page(target
);
2065 * At migration, we may charge account against cgroup which has no tasks
2066 * So, rmdir()->pre_destroy() can be called while we do this charge.
2067 * In that case, we need to call pre_destroy() again. check it here.
2069 cgroup_release_and_wakeup_rmdir(&mem
->css
);
2073 * A call to try to shrink memory usage on charge failure at shmem's swapin.
2074 * Calling hierarchical_reclaim is not enough because we should update
2075 * last_oom_jiffies to prevent pagefault_out_of_memory from invoking global OOM.
2076 * Moreover considering hierarchy, we should reclaim from the mem_over_limit,
2077 * not from the memcg which this page would be charged to.
2078 * try_charge_swapin does all of these works properly.
2080 int mem_cgroup_shmem_charge_fallback(struct page
*page
,
2081 struct mm_struct
*mm
,
2084 struct mem_cgroup
*mem
= NULL
;
2087 if (mem_cgroup_disabled())
2090 ret
= mem_cgroup_try_charge_swapin(mm
, page
, gfp_mask
, &mem
);
2092 mem_cgroup_cancel_charge_swapin(mem
); /* it does !mem check */
2097 static DEFINE_MUTEX(set_limit_mutex
);
2099 static int mem_cgroup_resize_limit(struct mem_cgroup
*memcg
,
2100 unsigned long long val
)
2106 int children
= mem_cgroup_count_children(memcg
);
2107 u64 curusage
, oldusage
;
2110 * For keeping hierarchical_reclaim simple, how long we should retry
2111 * is depends on callers. We set our retry-count to be function
2112 * of # of children which we should visit in this loop.
2114 retry_count
= MEM_CGROUP_RECLAIM_RETRIES
* children
;
2116 oldusage
= res_counter_read_u64(&memcg
->res
, RES_USAGE
);
2118 while (retry_count
) {
2119 if (signal_pending(current
)) {
2124 * Rather than hide all in some function, I do this in
2125 * open coded manner. You see what this really does.
2126 * We have to guarantee mem->res.limit < mem->memsw.limit.
2128 mutex_lock(&set_limit_mutex
);
2129 memswlimit
= res_counter_read_u64(&memcg
->memsw
, RES_LIMIT
);
2130 if (memswlimit
< val
) {
2132 mutex_unlock(&set_limit_mutex
);
2135 ret
= res_counter_set_limit(&memcg
->res
, val
);
2137 if (memswlimit
== val
)
2138 memcg
->memsw_is_minimum
= true;
2140 memcg
->memsw_is_minimum
= false;
2142 mutex_unlock(&set_limit_mutex
);
2147 progress
= mem_cgroup_hierarchical_reclaim(memcg
, NULL
,
2149 MEM_CGROUP_RECLAIM_SHRINK
);
2150 curusage
= res_counter_read_u64(&memcg
->res
, RES_USAGE
);
2151 /* Usage is reduced ? */
2152 if (curusage
>= oldusage
)
2155 oldusage
= curusage
;
2161 static int mem_cgroup_resize_memsw_limit(struct mem_cgroup
*memcg
,
2162 unsigned long long val
)
2165 u64 memlimit
, oldusage
, curusage
;
2166 int children
= mem_cgroup_count_children(memcg
);
2169 /* see mem_cgroup_resize_res_limit */
2170 retry_count
= children
* MEM_CGROUP_RECLAIM_RETRIES
;
2171 oldusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
2172 while (retry_count
) {
2173 if (signal_pending(current
)) {
2178 * Rather than hide all in some function, I do this in
2179 * open coded manner. You see what this really does.
2180 * We have to guarantee mem->res.limit < mem->memsw.limit.
2182 mutex_lock(&set_limit_mutex
);
2183 memlimit
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
);
2184 if (memlimit
> val
) {
2186 mutex_unlock(&set_limit_mutex
);
2189 ret
= res_counter_set_limit(&memcg
->memsw
, val
);
2191 if (memlimit
== val
)
2192 memcg
->memsw_is_minimum
= true;
2194 memcg
->memsw_is_minimum
= false;
2196 mutex_unlock(&set_limit_mutex
);
2201 mem_cgroup_hierarchical_reclaim(memcg
, NULL
, GFP_KERNEL
,
2202 MEM_CGROUP_RECLAIM_NOSWAP
|
2203 MEM_CGROUP_RECLAIM_SHRINK
);
2204 curusage
= res_counter_read_u64(&memcg
->memsw
, RES_USAGE
);
2205 /* Usage is reduced ? */
2206 if (curusage
>= oldusage
)
2209 oldusage
= curusage
;
2214 unsigned long mem_cgroup_soft_limit_reclaim(struct zone
*zone
, int order
,
2215 gfp_t gfp_mask
, int nid
,
2218 unsigned long nr_reclaimed
= 0;
2219 struct mem_cgroup_per_zone
*mz
, *next_mz
= NULL
;
2220 unsigned long reclaimed
;
2222 struct mem_cgroup_tree_per_zone
*mctz
;
2223 unsigned long long excess
;
2228 mctz
= soft_limit_tree_node_zone(nid
, zid
);
2230 * This loop can run a while, specially if mem_cgroup's continuously
2231 * keep exceeding their soft limit and putting the system under
2238 mz
= mem_cgroup_largest_soft_limit_node(mctz
);
2242 reclaimed
= mem_cgroup_hierarchical_reclaim(mz
->mem
, zone
,
2244 MEM_CGROUP_RECLAIM_SOFT
);
2245 nr_reclaimed
+= reclaimed
;
2246 spin_lock(&mctz
->lock
);
2249 * If we failed to reclaim anything from this memory cgroup
2250 * it is time to move on to the next cgroup
2256 * Loop until we find yet another one.
2258 * By the time we get the soft_limit lock
2259 * again, someone might have aded the
2260 * group back on the RB tree. Iterate to
2261 * make sure we get a different mem.
2262 * mem_cgroup_largest_soft_limit_node returns
2263 * NULL if no other cgroup is present on
2267 __mem_cgroup_largest_soft_limit_node(mctz
);
2268 if (next_mz
== mz
) {
2269 css_put(&next_mz
->mem
->css
);
2271 } else /* next_mz == NULL or other memcg */
2275 __mem_cgroup_remove_exceeded(mz
->mem
, mz
, mctz
);
2276 excess
= res_counter_soft_limit_excess(&mz
->mem
->res
);
2278 * One school of thought says that we should not add
2279 * back the node to the tree if reclaim returns 0.
2280 * But our reclaim could return 0, simply because due
2281 * to priority we are exposing a smaller subset of
2282 * memory to reclaim from. Consider this as a longer
2285 /* If excess == 0, no tree ops */
2286 __mem_cgroup_insert_exceeded(mz
->mem
, mz
, mctz
, excess
);
2287 spin_unlock(&mctz
->lock
);
2288 css_put(&mz
->mem
->css
);
2291 * Could not reclaim anything and there are no more
2292 * mem cgroups to try or we seem to be looping without
2293 * reclaiming anything.
2295 if (!nr_reclaimed
&&
2297 loop
> MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS
))
2299 } while (!nr_reclaimed
);
2301 css_put(&next_mz
->mem
->css
);
2302 return nr_reclaimed
;
2306 * This routine traverse page_cgroup in given list and drop them all.
2307 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
2309 static int mem_cgroup_force_empty_list(struct mem_cgroup
*mem
,
2310 int node
, int zid
, enum lru_list lru
)
2313 struct mem_cgroup_per_zone
*mz
;
2314 struct page_cgroup
*pc
, *busy
;
2315 unsigned long flags
, loop
;
2316 struct list_head
*list
;
2319 zone
= &NODE_DATA(node
)->node_zones
[zid
];
2320 mz
= mem_cgroup_zoneinfo(mem
, node
, zid
);
2321 list
= &mz
->lists
[lru
];
2323 loop
= MEM_CGROUP_ZSTAT(mz
, lru
);
2324 /* give some margin against EBUSY etc...*/
2329 spin_lock_irqsave(&zone
->lru_lock
, flags
);
2330 if (list_empty(list
)) {
2331 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
2334 pc
= list_entry(list
->prev
, struct page_cgroup
, lru
);
2336 list_move(&pc
->lru
, list
);
2338 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
2341 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
2343 ret
= mem_cgroup_move_parent(pc
, mem
, GFP_KERNEL
);
2347 if (ret
== -EBUSY
|| ret
== -EINVAL
) {
2348 /* found lock contention or "pc" is obsolete. */
2355 if (!ret
&& !list_empty(list
))
2361 * make mem_cgroup's charge to be 0 if there is no task.
2362 * This enables deleting this mem_cgroup.
2364 static int mem_cgroup_force_empty(struct mem_cgroup
*mem
, bool free_all
)
2367 int node
, zid
, shrink
;
2368 int nr_retries
= MEM_CGROUP_RECLAIM_RETRIES
;
2369 struct cgroup
*cgrp
= mem
->css
.cgroup
;
2374 /* should free all ? */
2378 while (mem
->res
.usage
> 0) {
2380 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
))
2383 if (signal_pending(current
))
2385 /* This is for making all *used* pages to be on LRU. */
2386 lru_add_drain_all();
2388 for_each_node_state(node
, N_HIGH_MEMORY
) {
2389 for (zid
= 0; !ret
&& zid
< MAX_NR_ZONES
; zid
++) {
2392 ret
= mem_cgroup_force_empty_list(mem
,
2401 /* it seems parent cgroup doesn't have enough mem */
2412 /* returns EBUSY if there is a task or if we come here twice. */
2413 if (cgroup_task_count(cgrp
) || !list_empty(&cgrp
->children
) || shrink
) {
2417 /* we call try-to-free pages for make this cgroup empty */
2418 lru_add_drain_all();
2419 /* try to free all pages in this cgroup */
2421 while (nr_retries
&& mem
->res
.usage
> 0) {
2424 if (signal_pending(current
)) {
2428 progress
= try_to_free_mem_cgroup_pages(mem
, GFP_KERNEL
,
2429 false, get_swappiness(mem
));
2432 /* maybe some writeback is necessary */
2433 congestion_wait(BLK_RW_ASYNC
, HZ
/10);
2438 /* try move_account...there may be some *locked* pages. */
2445 int mem_cgroup_force_empty_write(struct cgroup
*cont
, unsigned int event
)
2447 return mem_cgroup_force_empty(mem_cgroup_from_cont(cont
), true);
2451 static u64
mem_cgroup_hierarchy_read(struct cgroup
*cont
, struct cftype
*cft
)
2453 return mem_cgroup_from_cont(cont
)->use_hierarchy
;
2456 static int mem_cgroup_hierarchy_write(struct cgroup
*cont
, struct cftype
*cft
,
2460 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
2461 struct cgroup
*parent
= cont
->parent
;
2462 struct mem_cgroup
*parent_mem
= NULL
;
2465 parent_mem
= mem_cgroup_from_cont(parent
);
2469 * If parent's use_hiearchy is set, we can't make any modifications
2470 * in the child subtrees. If it is unset, then the change can
2471 * occur, provided the current cgroup has no children.
2473 * For the root cgroup, parent_mem is NULL, we allow value to be
2474 * set if there are no children.
2476 if ((!parent_mem
|| !parent_mem
->use_hierarchy
) &&
2477 (val
== 1 || val
== 0)) {
2478 if (list_empty(&cont
->children
))
2479 mem
->use_hierarchy
= val
;
2489 struct mem_cgroup_idx_data
{
2491 enum mem_cgroup_stat_index idx
;
2495 mem_cgroup_get_idx_stat(struct mem_cgroup
*mem
, void *data
)
2497 struct mem_cgroup_idx_data
*d
= data
;
2498 d
->val
+= mem_cgroup_read_stat(&mem
->stat
, d
->idx
);
2503 mem_cgroup_get_recursive_idx_stat(struct mem_cgroup
*mem
,
2504 enum mem_cgroup_stat_index idx
, s64
*val
)
2506 struct mem_cgroup_idx_data d
;
2509 mem_cgroup_walk_tree(mem
, &d
, mem_cgroup_get_idx_stat
);
2513 static u64
mem_cgroup_read(struct cgroup
*cont
, struct cftype
*cft
)
2515 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
2519 type
= MEMFILE_TYPE(cft
->private);
2520 name
= MEMFILE_ATTR(cft
->private);
2523 if (name
== RES_USAGE
&& mem_cgroup_is_root(mem
)) {
2524 mem_cgroup_get_recursive_idx_stat(mem
,
2525 MEM_CGROUP_STAT_CACHE
, &idx_val
);
2527 mem_cgroup_get_recursive_idx_stat(mem
,
2528 MEM_CGROUP_STAT_RSS
, &idx_val
);
2532 val
= res_counter_read_u64(&mem
->res
, name
);
2535 if (name
== RES_USAGE
&& mem_cgroup_is_root(mem
)) {
2536 mem_cgroup_get_recursive_idx_stat(mem
,
2537 MEM_CGROUP_STAT_CACHE
, &idx_val
);
2539 mem_cgroup_get_recursive_idx_stat(mem
,
2540 MEM_CGROUP_STAT_RSS
, &idx_val
);
2542 mem_cgroup_get_recursive_idx_stat(mem
,
2543 MEM_CGROUP_STAT_SWAPOUT
, &idx_val
);
2546 val
= res_counter_read_u64(&mem
->memsw
, name
);
2555 * The user of this function is...
2558 static int mem_cgroup_write(struct cgroup
*cont
, struct cftype
*cft
,
2561 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cont
);
2563 unsigned long long val
;
2566 type
= MEMFILE_TYPE(cft
->private);
2567 name
= MEMFILE_ATTR(cft
->private);
2570 if (mem_cgroup_is_root(memcg
)) { /* Can't set limit on root */
2574 /* This function does all necessary parse...reuse it */
2575 ret
= res_counter_memparse_write_strategy(buffer
, &val
);
2579 ret
= mem_cgroup_resize_limit(memcg
, val
);
2581 ret
= mem_cgroup_resize_memsw_limit(memcg
, val
);
2583 case RES_SOFT_LIMIT
:
2584 ret
= res_counter_memparse_write_strategy(buffer
, &val
);
2588 * For memsw, soft limits are hard to implement in terms
2589 * of semantics, for now, we support soft limits for
2590 * control without swap
2593 ret
= res_counter_set_soft_limit(&memcg
->res
, val
);
2598 ret
= -EINVAL
; /* should be BUG() ? */
2604 static void memcg_get_hierarchical_limit(struct mem_cgroup
*memcg
,
2605 unsigned long long *mem_limit
, unsigned long long *memsw_limit
)
2607 struct cgroup
*cgroup
;
2608 unsigned long long min_limit
, min_memsw_limit
, tmp
;
2610 min_limit
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
);
2611 min_memsw_limit
= res_counter_read_u64(&memcg
->memsw
, RES_LIMIT
);
2612 cgroup
= memcg
->css
.cgroup
;
2613 if (!memcg
->use_hierarchy
)
2616 while (cgroup
->parent
) {
2617 cgroup
= cgroup
->parent
;
2618 memcg
= mem_cgroup_from_cont(cgroup
);
2619 if (!memcg
->use_hierarchy
)
2621 tmp
= res_counter_read_u64(&memcg
->res
, RES_LIMIT
);
2622 min_limit
= min(min_limit
, tmp
);
2623 tmp
= res_counter_read_u64(&memcg
->memsw
, RES_LIMIT
);
2624 min_memsw_limit
= min(min_memsw_limit
, tmp
);
2627 *mem_limit
= min_limit
;
2628 *memsw_limit
= min_memsw_limit
;
2632 static int mem_cgroup_reset(struct cgroup
*cont
, unsigned int event
)
2634 struct mem_cgroup
*mem
;
2637 mem
= mem_cgroup_from_cont(cont
);
2638 type
= MEMFILE_TYPE(event
);
2639 name
= MEMFILE_ATTR(event
);
2643 res_counter_reset_max(&mem
->res
);
2645 res_counter_reset_max(&mem
->memsw
);
2649 res_counter_reset_failcnt(&mem
->res
);
2651 res_counter_reset_failcnt(&mem
->memsw
);
2659 /* For read statistics */
2675 struct mcs_total_stat
{
2676 s64 stat
[NR_MCS_STAT
];
2682 } memcg_stat_strings
[NR_MCS_STAT
] = {
2683 {"cache", "total_cache"},
2684 {"rss", "total_rss"},
2685 {"mapped_file", "total_mapped_file"},
2686 {"pgpgin", "total_pgpgin"},
2687 {"pgpgout", "total_pgpgout"},
2688 {"swap", "total_swap"},
2689 {"inactive_anon", "total_inactive_anon"},
2690 {"active_anon", "total_active_anon"},
2691 {"inactive_file", "total_inactive_file"},
2692 {"active_file", "total_active_file"},
2693 {"unevictable", "total_unevictable"}
2697 static int mem_cgroup_get_local_stat(struct mem_cgroup
*mem
, void *data
)
2699 struct mcs_total_stat
*s
= data
;
2703 val
= mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_CACHE
);
2704 s
->stat
[MCS_CACHE
] += val
* PAGE_SIZE
;
2705 val
= mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_RSS
);
2706 s
->stat
[MCS_RSS
] += val
* PAGE_SIZE
;
2707 val
= mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_MAPPED_FILE
);
2708 s
->stat
[MCS_MAPPED_FILE
] += val
* PAGE_SIZE
;
2709 val
= mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_PGPGIN_COUNT
);
2710 s
->stat
[MCS_PGPGIN
] += val
;
2711 val
= mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_PGPGOUT_COUNT
);
2712 s
->stat
[MCS_PGPGOUT
] += val
;
2713 if (do_swap_account
) {
2714 val
= mem_cgroup_read_stat(&mem
->stat
, MEM_CGROUP_STAT_SWAPOUT
);
2715 s
->stat
[MCS_SWAP
] += val
* PAGE_SIZE
;
2719 val
= mem_cgroup_get_local_zonestat(mem
, LRU_INACTIVE_ANON
);
2720 s
->stat
[MCS_INACTIVE_ANON
] += val
* PAGE_SIZE
;
2721 val
= mem_cgroup_get_local_zonestat(mem
, LRU_ACTIVE_ANON
);
2722 s
->stat
[MCS_ACTIVE_ANON
] += val
* PAGE_SIZE
;
2723 val
= mem_cgroup_get_local_zonestat(mem
, LRU_INACTIVE_FILE
);
2724 s
->stat
[MCS_INACTIVE_FILE
] += val
* PAGE_SIZE
;
2725 val
= mem_cgroup_get_local_zonestat(mem
, LRU_ACTIVE_FILE
);
2726 s
->stat
[MCS_ACTIVE_FILE
] += val
* PAGE_SIZE
;
2727 val
= mem_cgroup_get_local_zonestat(mem
, LRU_UNEVICTABLE
);
2728 s
->stat
[MCS_UNEVICTABLE
] += val
* PAGE_SIZE
;
2733 mem_cgroup_get_total_stat(struct mem_cgroup
*mem
, struct mcs_total_stat
*s
)
2735 mem_cgroup_walk_tree(mem
, s
, mem_cgroup_get_local_stat
);
2738 static int mem_control_stat_show(struct cgroup
*cont
, struct cftype
*cft
,
2739 struct cgroup_map_cb
*cb
)
2741 struct mem_cgroup
*mem_cont
= mem_cgroup_from_cont(cont
);
2742 struct mcs_total_stat mystat
;
2745 memset(&mystat
, 0, sizeof(mystat
));
2746 mem_cgroup_get_local_stat(mem_cont
, &mystat
);
2748 for (i
= 0; i
< NR_MCS_STAT
; i
++) {
2749 if (i
== MCS_SWAP
&& !do_swap_account
)
2751 cb
->fill(cb
, memcg_stat_strings
[i
].local_name
, mystat
.stat
[i
]);
2754 /* Hierarchical information */
2756 unsigned long long limit
, memsw_limit
;
2757 memcg_get_hierarchical_limit(mem_cont
, &limit
, &memsw_limit
);
2758 cb
->fill(cb
, "hierarchical_memory_limit", limit
);
2759 if (do_swap_account
)
2760 cb
->fill(cb
, "hierarchical_memsw_limit", memsw_limit
);
2763 memset(&mystat
, 0, sizeof(mystat
));
2764 mem_cgroup_get_total_stat(mem_cont
, &mystat
);
2765 for (i
= 0; i
< NR_MCS_STAT
; i
++) {
2766 if (i
== MCS_SWAP
&& !do_swap_account
)
2768 cb
->fill(cb
, memcg_stat_strings
[i
].total_name
, mystat
.stat
[i
]);
2771 #ifdef CONFIG_DEBUG_VM
2772 cb
->fill(cb
, "inactive_ratio", calc_inactive_ratio(mem_cont
, NULL
));
2776 struct mem_cgroup_per_zone
*mz
;
2777 unsigned long recent_rotated
[2] = {0, 0};
2778 unsigned long recent_scanned
[2] = {0, 0};
2780 for_each_online_node(nid
)
2781 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
2782 mz
= mem_cgroup_zoneinfo(mem_cont
, nid
, zid
);
2784 recent_rotated
[0] +=
2785 mz
->reclaim_stat
.recent_rotated
[0];
2786 recent_rotated
[1] +=
2787 mz
->reclaim_stat
.recent_rotated
[1];
2788 recent_scanned
[0] +=
2789 mz
->reclaim_stat
.recent_scanned
[0];
2790 recent_scanned
[1] +=
2791 mz
->reclaim_stat
.recent_scanned
[1];
2793 cb
->fill(cb
, "recent_rotated_anon", recent_rotated
[0]);
2794 cb
->fill(cb
, "recent_rotated_file", recent_rotated
[1]);
2795 cb
->fill(cb
, "recent_scanned_anon", recent_scanned
[0]);
2796 cb
->fill(cb
, "recent_scanned_file", recent_scanned
[1]);
2803 static u64
mem_cgroup_swappiness_read(struct cgroup
*cgrp
, struct cftype
*cft
)
2805 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cgrp
);
2807 return get_swappiness(memcg
);
2810 static int mem_cgroup_swappiness_write(struct cgroup
*cgrp
, struct cftype
*cft
,
2813 struct mem_cgroup
*memcg
= mem_cgroup_from_cont(cgrp
);
2814 struct mem_cgroup
*parent
;
2819 if (cgrp
->parent
== NULL
)
2822 parent
= mem_cgroup_from_cont(cgrp
->parent
);
2826 /* If under hierarchy, only empty-root can set this value */
2827 if ((parent
->use_hierarchy
) ||
2828 (memcg
->use_hierarchy
&& !list_empty(&cgrp
->children
))) {
2833 spin_lock(&memcg
->reclaim_param_lock
);
2834 memcg
->swappiness
= val
;
2835 spin_unlock(&memcg
->reclaim_param_lock
);
2843 static struct cftype mem_cgroup_files
[] = {
2845 .name
= "usage_in_bytes",
2846 .private = MEMFILE_PRIVATE(_MEM
, RES_USAGE
),
2847 .read_u64
= mem_cgroup_read
,
2850 .name
= "max_usage_in_bytes",
2851 .private = MEMFILE_PRIVATE(_MEM
, RES_MAX_USAGE
),
2852 .trigger
= mem_cgroup_reset
,
2853 .read_u64
= mem_cgroup_read
,
2856 .name
= "limit_in_bytes",
2857 .private = MEMFILE_PRIVATE(_MEM
, RES_LIMIT
),
2858 .write_string
= mem_cgroup_write
,
2859 .read_u64
= mem_cgroup_read
,
2862 .name
= "soft_limit_in_bytes",
2863 .private = MEMFILE_PRIVATE(_MEM
, RES_SOFT_LIMIT
),
2864 .write_string
= mem_cgroup_write
,
2865 .read_u64
= mem_cgroup_read
,
2869 .private = MEMFILE_PRIVATE(_MEM
, RES_FAILCNT
),
2870 .trigger
= mem_cgroup_reset
,
2871 .read_u64
= mem_cgroup_read
,
2875 .read_map
= mem_control_stat_show
,
2878 .name
= "force_empty",
2879 .trigger
= mem_cgroup_force_empty_write
,
2882 .name
= "use_hierarchy",
2883 .write_u64
= mem_cgroup_hierarchy_write
,
2884 .read_u64
= mem_cgroup_hierarchy_read
,
2887 .name
= "swappiness",
2888 .read_u64
= mem_cgroup_swappiness_read
,
2889 .write_u64
= mem_cgroup_swappiness_write
,
2893 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2894 static struct cftype memsw_cgroup_files
[] = {
2896 .name
= "memsw.usage_in_bytes",
2897 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_USAGE
),
2898 .read_u64
= mem_cgroup_read
,
2901 .name
= "memsw.max_usage_in_bytes",
2902 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_MAX_USAGE
),
2903 .trigger
= mem_cgroup_reset
,
2904 .read_u64
= mem_cgroup_read
,
2907 .name
= "memsw.limit_in_bytes",
2908 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_LIMIT
),
2909 .write_string
= mem_cgroup_write
,
2910 .read_u64
= mem_cgroup_read
,
2913 .name
= "memsw.failcnt",
2914 .private = MEMFILE_PRIVATE(_MEMSWAP
, RES_FAILCNT
),
2915 .trigger
= mem_cgroup_reset
,
2916 .read_u64
= mem_cgroup_read
,
2920 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
2922 if (!do_swap_account
)
2924 return cgroup_add_files(cont
, ss
, memsw_cgroup_files
,
2925 ARRAY_SIZE(memsw_cgroup_files
));
2928 static int register_memsw_files(struct cgroup
*cont
, struct cgroup_subsys
*ss
)
2934 static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
2936 struct mem_cgroup_per_node
*pn
;
2937 struct mem_cgroup_per_zone
*mz
;
2939 int zone
, tmp
= node
;
2941 * This routine is called against possible nodes.
2942 * But it's BUG to call kmalloc() against offline node.
2944 * TODO: this routine can waste much memory for nodes which will
2945 * never be onlined. It's better to use memory hotplug callback
2948 if (!node_state(node
, N_NORMAL_MEMORY
))
2950 pn
= kmalloc_node(sizeof(*pn
), GFP_KERNEL
, tmp
);
2954 mem
->info
.nodeinfo
[node
] = pn
;
2955 memset(pn
, 0, sizeof(*pn
));
2957 for (zone
= 0; zone
< MAX_NR_ZONES
; zone
++) {
2958 mz
= &pn
->zoneinfo
[zone
];
2960 INIT_LIST_HEAD(&mz
->lists
[l
]);
2961 mz
->usage_in_excess
= 0;
2962 mz
->on_tree
= false;
2968 static void free_mem_cgroup_per_zone_info(struct mem_cgroup
*mem
, int node
)
2970 kfree(mem
->info
.nodeinfo
[node
]);
2973 static int mem_cgroup_size(void)
2975 int cpustat_size
= nr_cpu_ids
* sizeof(struct mem_cgroup_stat_cpu
);
2976 return sizeof(struct mem_cgroup
) + cpustat_size
;
2979 static struct mem_cgroup
*mem_cgroup_alloc(void)
2981 struct mem_cgroup
*mem
;
2982 int size
= mem_cgroup_size();
2984 if (size
< PAGE_SIZE
)
2985 mem
= kmalloc(size
, GFP_KERNEL
);
2987 mem
= vmalloc(size
);
2990 memset(mem
, 0, size
);
2995 * At destroying mem_cgroup, references from swap_cgroup can remain.
2996 * (scanning all at force_empty is too costly...)
2998 * Instead of clearing all references at force_empty, we remember
2999 * the number of reference from swap_cgroup and free mem_cgroup when
3000 * it goes down to 0.
3002 * Removal of cgroup itself succeeds regardless of refs from swap.
3005 static void __mem_cgroup_free(struct mem_cgroup
*mem
)
3009 mem_cgroup_remove_from_trees(mem
);
3010 free_css_id(&mem_cgroup_subsys
, &mem
->css
);
3012 for_each_node_state(node
, N_POSSIBLE
)
3013 free_mem_cgroup_per_zone_info(mem
, node
);
3015 if (mem_cgroup_size() < PAGE_SIZE
)
3021 static void mem_cgroup_get(struct mem_cgroup
*mem
)
3023 atomic_inc(&mem
->refcnt
);
3026 static void mem_cgroup_put(struct mem_cgroup
*mem
)
3028 if (atomic_dec_and_test(&mem
->refcnt
)) {
3029 struct mem_cgroup
*parent
= parent_mem_cgroup(mem
);
3030 __mem_cgroup_free(mem
);
3032 mem_cgroup_put(parent
);
3037 * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled.
3039 static struct mem_cgroup
*parent_mem_cgroup(struct mem_cgroup
*mem
)
3041 if (!mem
->res
.parent
)
3043 return mem_cgroup_from_res_counter(mem
->res
.parent
, res
);
3046 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
3047 static void __init
enable_swap_cgroup(void)
3049 if (!mem_cgroup_disabled() && really_do_swap_account
)
3050 do_swap_account
= 1;
3053 static void __init
enable_swap_cgroup(void)
3058 static int mem_cgroup_soft_limit_tree_init(void)
3060 struct mem_cgroup_tree_per_node
*rtpn
;
3061 struct mem_cgroup_tree_per_zone
*rtpz
;
3062 int tmp
, node
, zone
;
3064 for_each_node_state(node
, N_POSSIBLE
) {
3066 if (!node_state(node
, N_NORMAL_MEMORY
))
3068 rtpn
= kzalloc_node(sizeof(*rtpn
), GFP_KERNEL
, tmp
);
3072 soft_limit_tree
.rb_tree_per_node
[node
] = rtpn
;
3074 for (zone
= 0; zone
< MAX_NR_ZONES
; zone
++) {
3075 rtpz
= &rtpn
->rb_tree_per_zone
[zone
];
3076 rtpz
->rb_root
= RB_ROOT
;
3077 spin_lock_init(&rtpz
->lock
);
3083 static struct cgroup_subsys_state
* __ref
3084 mem_cgroup_create(struct cgroup_subsys
*ss
, struct cgroup
*cont
)
3086 struct mem_cgroup
*mem
, *parent
;
3087 long error
= -ENOMEM
;
3090 mem
= mem_cgroup_alloc();
3092 return ERR_PTR(error
);
3094 for_each_node_state(node
, N_POSSIBLE
)
3095 if (alloc_mem_cgroup_per_zone_info(mem
, node
))
3099 if (cont
->parent
== NULL
) {
3100 enable_swap_cgroup();
3102 root_mem_cgroup
= mem
;
3103 if (mem_cgroup_soft_limit_tree_init())
3107 parent
= mem_cgroup_from_cont(cont
->parent
);
3108 mem
->use_hierarchy
= parent
->use_hierarchy
;
3111 if (parent
&& parent
->use_hierarchy
) {
3112 res_counter_init(&mem
->res
, &parent
->res
);
3113 res_counter_init(&mem
->memsw
, &parent
->memsw
);
3115 * We increment refcnt of the parent to ensure that we can
3116 * safely access it on res_counter_charge/uncharge.
3117 * This refcnt will be decremented when freeing this
3118 * mem_cgroup(see mem_cgroup_put).
3120 mem_cgroup_get(parent
);
3122 res_counter_init(&mem
->res
, NULL
);
3123 res_counter_init(&mem
->memsw
, NULL
);
3125 mem
->last_scanned_child
= 0;
3126 spin_lock_init(&mem
->reclaim_param_lock
);
3129 mem
->swappiness
= get_swappiness(parent
);
3130 atomic_set(&mem
->refcnt
, 1);
3133 __mem_cgroup_free(mem
);
3134 root_mem_cgroup
= NULL
;
3135 return ERR_PTR(error
);
3138 static int mem_cgroup_pre_destroy(struct cgroup_subsys
*ss
,
3139 struct cgroup
*cont
)
3141 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
3143 return mem_cgroup_force_empty(mem
, false);
3146 static void mem_cgroup_destroy(struct cgroup_subsys
*ss
,
3147 struct cgroup
*cont
)
3149 struct mem_cgroup
*mem
= mem_cgroup_from_cont(cont
);
3151 mem_cgroup_put(mem
);
3154 static int mem_cgroup_populate(struct cgroup_subsys
*ss
,
3155 struct cgroup
*cont
)
3159 ret
= cgroup_add_files(cont
, ss
, mem_cgroup_files
,
3160 ARRAY_SIZE(mem_cgroup_files
));
3163 ret
= register_memsw_files(cont
, ss
);
3167 static void mem_cgroup_move_task(struct cgroup_subsys
*ss
,
3168 struct cgroup
*cont
,
3169 struct cgroup
*old_cont
,
3170 struct task_struct
*p
,
3173 mutex_lock(&memcg_tasklist
);
3175 * FIXME: It's better to move charges of this process from old
3176 * memcg to new memcg. But it's just on TODO-List now.
3178 mutex_unlock(&memcg_tasklist
);
3181 struct cgroup_subsys mem_cgroup_subsys
= {
3183 .subsys_id
= mem_cgroup_subsys_id
,
3184 .create
= mem_cgroup_create
,
3185 .pre_destroy
= mem_cgroup_pre_destroy
,
3186 .destroy
= mem_cgroup_destroy
,
3187 .populate
= mem_cgroup_populate
,
3188 .attach
= mem_cgroup_move_task
,
3193 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
3195 static int __init
disable_swap_account(char *s
)
3197 really_do_swap_account
= 0;
3200 __setup("noswapaccount", disable_swap_account
);