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);