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)
54 static DEFINE_MUTEX(memcg_tasklist); /* can be hold under cgroup_mutex */
57 * Statistics for memory cgroup.
59 enum mem_cgroup_stat_index {
61 * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
63 MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */
64 MEM_CGROUP_STAT_RSS, /* # of pages charged as rss */
65 MEM_CGROUP_STAT_PGPGIN_COUNT, /* # of pages paged in */
66 MEM_CGROUP_STAT_PGPGOUT_COUNT, /* # of pages paged out */
68 MEM_CGROUP_STAT_NSTATS,
71 struct mem_cgroup_stat_cpu {
72 s64 count[MEM_CGROUP_STAT_NSTATS];
73 } ____cacheline_aligned_in_smp;
75 struct mem_cgroup_stat {
76 struct mem_cgroup_stat_cpu cpustat[0];
80 * For accounting under irq disable, no need for increment preempt count.
82 static inline void __mem_cgroup_stat_add_safe(struct mem_cgroup_stat_cpu *stat,
83 enum mem_cgroup_stat_index idx, int val)
85 stat->count[idx] += val;
88 static s64 mem_cgroup_read_stat(struct mem_cgroup_stat *stat,
89 enum mem_cgroup_stat_index idx)
93 for_each_possible_cpu(cpu)
94 ret += stat->cpustat[cpu].count[idx];
99 * per-zone information in memory controller.
101 struct mem_cgroup_per_zone {
103 * spin_lock to protect the per cgroup LRU
105 struct list_head lists[NR_LRU_LISTS];
106 unsigned long count[NR_LRU_LISTS];
108 struct zone_reclaim_stat reclaim_stat;
110 /* Macro for accessing counter */
111 #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)])
113 struct mem_cgroup_per_node {
114 struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES];
117 struct mem_cgroup_lru_info {
118 struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES];
122 * The memory controller data structure. The memory controller controls both
123 * page cache and RSS per cgroup. We would eventually like to provide
124 * statistics based on the statistics developed by Rik Van Riel for clock-pro,
125 * to help the administrator determine what knobs to tune.
127 * TODO: Add a water mark for the memory controller. Reclaim will begin when
128 * we hit the water mark. May be even add a low water mark, such that
129 * no reclaim occurs from a cgroup at it's low water mark, this is
130 * a feature that will be implemented much later in the future.
133 struct cgroup_subsys_state css;
135 * the counter to account for memory usage
137 struct res_counter res;
139 * the counter to account for mem+swap usage.
141 struct res_counter memsw;
143 * Per cgroup active and inactive list, similar to the
144 * per zone LRU lists.
146 struct mem_cgroup_lru_info info;
149 protect against reclaim related member.
151 spinlock_t reclaim_param_lock;
153 int prev_priority; /* for recording reclaim priority */
156 * While reclaiming in a hiearchy, we cache the last child we
157 * reclaimed from. Protected by cgroup_lock()
159 struct mem_cgroup *last_scanned_child;
161 * Should the accounting and control be hierarchical, per subtree?
164 unsigned long last_oom_jiffies;
168 unsigned int swappiness;
171 * statistics. This must be placed at the end of memcg.
173 struct mem_cgroup_stat stat;
177 MEM_CGROUP_CHARGE_TYPE_CACHE = 0,
178 MEM_CGROUP_CHARGE_TYPE_MAPPED,
179 MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */
180 MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */
181 MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */
185 /* only for here (for easy reading.) */
186 #define PCGF_CACHE (1UL << PCG_CACHE)
187 #define PCGF_USED (1UL << PCG_USED)
188 #define PCGF_LOCK (1UL << PCG_LOCK)
189 static const unsigned long
190 pcg_default_flags[NR_CHARGE_TYPE] = {
191 PCGF_CACHE | PCGF_USED | PCGF_LOCK, /* File Cache */
192 PCGF_USED | PCGF_LOCK, /* Anon */
193 PCGF_CACHE | PCGF_USED | PCGF_LOCK, /* Shmem */
197 /* for encoding cft->private value on file */
200 #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
201 #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
202 #define MEMFILE_ATTR(val) ((val) & 0xffff)
204 static void mem_cgroup_get(struct mem_cgroup *mem);
205 static void mem_cgroup_put(struct mem_cgroup *mem);
207 static void mem_cgroup_charge_statistics(struct mem_cgroup *mem,
208 struct page_cgroup *pc,
211 int val = (charge)? 1 : -1;
212 struct mem_cgroup_stat *stat = &mem->stat;
213 struct mem_cgroup_stat_cpu *cpustat;
216 cpustat = &stat->cpustat[cpu];
217 if (PageCgroupCache(pc))
218 __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_CACHE, val);
220 __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_RSS, val);
223 __mem_cgroup_stat_add_safe(cpustat,
224 MEM_CGROUP_STAT_PGPGIN_COUNT, 1);
226 __mem_cgroup_stat_add_safe(cpustat,
227 MEM_CGROUP_STAT_PGPGOUT_COUNT, 1);
231 static struct mem_cgroup_per_zone *
232 mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid)
234 return &mem->info.nodeinfo[nid]->zoneinfo[zid];
237 static struct mem_cgroup_per_zone *
238 page_cgroup_zoneinfo(struct page_cgroup *pc)
240 struct mem_cgroup *mem = pc->mem_cgroup;
241 int nid = page_cgroup_nid(pc);
242 int zid = page_cgroup_zid(pc);
247 return mem_cgroup_zoneinfo(mem, nid, zid);
250 static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup *mem,
254 struct mem_cgroup_per_zone *mz;
257 for_each_online_node(nid)
258 for (zid = 0; zid < MAX_NR_ZONES; zid++) {
259 mz = mem_cgroup_zoneinfo(mem, nid, zid);
260 total += MEM_CGROUP_ZSTAT(mz, idx);
265 static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont)
267 return container_of(cgroup_subsys_state(cont,
268 mem_cgroup_subsys_id), struct mem_cgroup,
272 struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p)
275 * mm_update_next_owner() may clear mm->owner to NULL
276 * if it races with swapoff, page migration, etc.
277 * So this can be called with p == NULL.
282 return container_of(task_subsys_state(p, mem_cgroup_subsys_id),
283 struct mem_cgroup, css);
287 * Following LRU functions are allowed to be used without PCG_LOCK.
288 * Operations are called by routine of global LRU independently from memcg.
289 * What we have to take care of here is validness of pc->mem_cgroup.
291 * Changes to pc->mem_cgroup happens when
294 * In typical case, "charge" is done before add-to-lru. Exception is SwapCache.
295 * It is added to LRU before charge.
296 * If PCG_USED bit is not set, page_cgroup is not added to this private LRU.
297 * When moving account, the page is not on LRU. It's isolated.
300 void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru)
302 struct page_cgroup *pc;
303 struct mem_cgroup *mem;
304 struct mem_cgroup_per_zone *mz;
306 if (mem_cgroup_disabled())
308 pc = lookup_page_cgroup(page);
309 /* can happen while we handle swapcache. */
310 if (list_empty(&pc->lru))
312 mz = page_cgroup_zoneinfo(pc);
313 mem = pc->mem_cgroup;
314 MEM_CGROUP_ZSTAT(mz, lru) -= 1;
315 list_del_init(&pc->lru);
319 void mem_cgroup_del_lru(struct page *page)
321 mem_cgroup_del_lru_list(page, page_lru(page));
324 void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru)
326 struct mem_cgroup_per_zone *mz;
327 struct page_cgroup *pc;
329 if (mem_cgroup_disabled())
332 pc = lookup_page_cgroup(page);
334 /* unused page is not rotated. */
335 if (!PageCgroupUsed(pc))
337 mz = page_cgroup_zoneinfo(pc);
338 list_move(&pc->lru, &mz->lists[lru]);
341 void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru)
343 struct page_cgroup *pc;
344 struct mem_cgroup_per_zone *mz;
346 if (mem_cgroup_disabled())
348 pc = lookup_page_cgroup(page);
349 /* barrier to sync with "charge" */
351 if (!PageCgroupUsed(pc))
354 mz = page_cgroup_zoneinfo(pc);
355 MEM_CGROUP_ZSTAT(mz, lru) += 1;
356 list_add(&pc->lru, &mz->lists[lru]);
359 * To add swapcache into LRU. Be careful to all this function.
360 * zone->lru_lock shouldn't be held and irq must not be disabled.
362 static void mem_cgroup_lru_fixup(struct page *page)
364 if (!isolate_lru_page(page))
365 putback_lru_page(page);
368 void mem_cgroup_move_lists(struct page *page,
369 enum lru_list from, enum lru_list to)
371 if (mem_cgroup_disabled())
373 mem_cgroup_del_lru_list(page, from);
374 mem_cgroup_add_lru_list(page, to);
377 int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem)
382 ret = task->mm && mm_match_cgroup(task->mm, mem);
388 * Calculate mapped_ratio under memory controller. This will be used in
389 * vmscan.c for deteremining we have to reclaim mapped pages.
391 int mem_cgroup_calc_mapped_ratio(struct mem_cgroup *mem)
396 * usage is recorded in bytes. But, here, we assume the number of
397 * physical pages can be represented by "long" on any arch.
399 total = (long) (mem->res.usage >> PAGE_SHIFT) + 1L;
400 rss = (long)mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_RSS);
401 return (int)((rss * 100L) / total);
405 * prev_priority control...this will be used in memory reclaim path.
407 int mem_cgroup_get_reclaim_priority(struct mem_cgroup *mem)
411 spin_lock(&mem->reclaim_param_lock);
412 prev_priority = mem->prev_priority;
413 spin_unlock(&mem->reclaim_param_lock);
415 return prev_priority;
418 void mem_cgroup_note_reclaim_priority(struct mem_cgroup *mem, int priority)
420 spin_lock(&mem->reclaim_param_lock);
421 if (priority < mem->prev_priority)
422 mem->prev_priority = priority;
423 spin_unlock(&mem->reclaim_param_lock);
426 void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, int priority)
428 spin_lock(&mem->reclaim_param_lock);
429 mem->prev_priority = priority;
430 spin_unlock(&mem->reclaim_param_lock);
433 static int calc_inactive_ratio(struct mem_cgroup *memcg, unsigned long *present_pages)
435 unsigned long active;
436 unsigned long inactive;
438 unsigned long inactive_ratio;
440 inactive = mem_cgroup_get_all_zonestat(memcg, LRU_INACTIVE_ANON);
441 active = mem_cgroup_get_all_zonestat(memcg, LRU_ACTIVE_ANON);
443 gb = (inactive + active) >> (30 - PAGE_SHIFT);
445 inactive_ratio = int_sqrt(10 * gb);
450 present_pages[0] = inactive;
451 present_pages[1] = active;
454 return inactive_ratio;
457 int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg)
459 unsigned long active;
460 unsigned long inactive;
461 unsigned long present_pages[2];
462 unsigned long inactive_ratio;
464 inactive_ratio = calc_inactive_ratio(memcg, present_pages);
466 inactive = present_pages[0];
467 active = present_pages[1];
469 if (inactive * inactive_ratio < active)
475 unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup *memcg,
479 int nid = zone->zone_pgdat->node_id;
480 int zid = zone_idx(zone);
481 struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid);
483 return MEM_CGROUP_ZSTAT(mz, lru);
486 struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg,
489 int nid = zone->zone_pgdat->node_id;
490 int zid = zone_idx(zone);
491 struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid);
493 return &mz->reclaim_stat;
496 struct zone_reclaim_stat *
497 mem_cgroup_get_reclaim_stat_from_page(struct page *page)
499 struct page_cgroup *pc;
500 struct mem_cgroup_per_zone *mz;
502 if (mem_cgroup_disabled())
505 pc = lookup_page_cgroup(page);
506 mz = page_cgroup_zoneinfo(pc);
510 return &mz->reclaim_stat;
513 unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
514 struct list_head *dst,
515 unsigned long *scanned, int order,
516 int mode, struct zone *z,
517 struct mem_cgroup *mem_cont,
518 int active, int file)
520 unsigned long nr_taken = 0;
524 struct list_head *src;
525 struct page_cgroup *pc, *tmp;
526 int nid = z->zone_pgdat->node_id;
527 int zid = zone_idx(z);
528 struct mem_cgroup_per_zone *mz;
529 int lru = LRU_FILE * !!file + !!active;
532 mz = mem_cgroup_zoneinfo(mem_cont, nid, zid);
533 src = &mz->lists[lru];
536 list_for_each_entry_safe_reverse(pc, tmp, src, lru) {
537 if (scan >= nr_to_scan)
541 if (unlikely(!PageCgroupUsed(pc)))
543 if (unlikely(!PageLRU(page)))
547 if (__isolate_lru_page(page, mode, file) == 0) {
548 list_move(&page->lru, dst);
557 #define mem_cgroup_from_res_counter(counter, member) \
558 container_of(counter, struct mem_cgroup, member)
561 * This routine finds the DFS walk successor. This routine should be
562 * called with cgroup_mutex held
564 static struct mem_cgroup *
565 mem_cgroup_get_next_node(struct mem_cgroup *curr, struct mem_cgroup *root_mem)
567 struct cgroup *cgroup, *curr_cgroup, *root_cgroup;
569 curr_cgroup = curr->css.cgroup;
570 root_cgroup = root_mem->css.cgroup;
572 if (!list_empty(&curr_cgroup->children)) {
574 * Walk down to children
576 mem_cgroup_put(curr);
577 cgroup = list_entry(curr_cgroup->children.next,
578 struct cgroup, sibling);
579 curr = mem_cgroup_from_cont(cgroup);
580 mem_cgroup_get(curr);
585 if (curr_cgroup == root_cgroup) {
586 mem_cgroup_put(curr);
588 mem_cgroup_get(curr);
595 if (curr_cgroup->sibling.next != &curr_cgroup->parent->children) {
596 mem_cgroup_put(curr);
597 cgroup = list_entry(curr_cgroup->sibling.next, struct cgroup,
599 curr = mem_cgroup_from_cont(cgroup);
600 mem_cgroup_get(curr);
605 * Go up to next parent and next parent's sibling if need be
607 curr_cgroup = curr_cgroup->parent;
611 root_mem->last_scanned_child = curr;
616 * Visit the first child (need not be the first child as per the ordering
617 * of the cgroup list, since we track last_scanned_child) of @mem and use
618 * that to reclaim free pages from.
620 static struct mem_cgroup *
621 mem_cgroup_get_first_node(struct mem_cgroup *root_mem)
623 struct cgroup *cgroup;
624 struct mem_cgroup *ret;
625 bool obsolete = (root_mem->last_scanned_child &&
626 root_mem->last_scanned_child->obsolete);
629 * Scan all children under the mem_cgroup mem
632 if (list_empty(&root_mem->css.cgroup->children)) {
637 if (!root_mem->last_scanned_child || obsolete) {
640 mem_cgroup_put(root_mem->last_scanned_child);
642 cgroup = list_first_entry(&root_mem->css.cgroup->children,
643 struct cgroup, sibling);
644 ret = mem_cgroup_from_cont(cgroup);
647 ret = mem_cgroup_get_next_node(root_mem->last_scanned_child,
651 root_mem->last_scanned_child = ret;
656 static bool mem_cgroup_check_under_limit(struct mem_cgroup *mem)
658 if (do_swap_account) {
659 if (res_counter_check_under_limit(&mem->res) &&
660 res_counter_check_under_limit(&mem->memsw))
663 if (res_counter_check_under_limit(&mem->res))
668 static unsigned int get_swappiness(struct mem_cgroup *memcg)
670 struct cgroup *cgrp = memcg->css.cgroup;
671 unsigned int swappiness;
674 if (cgrp->parent == NULL)
675 return vm_swappiness;
677 spin_lock(&memcg->reclaim_param_lock);
678 swappiness = memcg->swappiness;
679 spin_unlock(&memcg->reclaim_param_lock);
685 * Dance down the hierarchy if needed to reclaim memory. We remember the
686 * last child we reclaimed from, so that we don't end up penalizing
687 * one child extensively based on its position in the children list.
689 * root_mem is the original ancestor that we've been reclaim from.
691 static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem,
692 gfp_t gfp_mask, bool noswap)
694 struct mem_cgroup *next_mem;
698 * Reclaim unconditionally and don't check for return value.
699 * We need to reclaim in the current group and down the tree.
700 * One might think about checking for children before reclaiming,
701 * but there might be left over accounting, even after children
704 ret = try_to_free_mem_cgroup_pages(root_mem, gfp_mask, noswap,
705 get_swappiness(root_mem));
706 if (mem_cgroup_check_under_limit(root_mem))
708 if (!root_mem->use_hierarchy)
711 next_mem = mem_cgroup_get_first_node(root_mem);
713 while (next_mem != root_mem) {
714 if (next_mem->obsolete) {
715 mem_cgroup_put(next_mem);
717 next_mem = mem_cgroup_get_first_node(root_mem);
721 ret = try_to_free_mem_cgroup_pages(next_mem, gfp_mask, noswap,
722 get_swappiness(next_mem));
723 if (mem_cgroup_check_under_limit(root_mem))
726 next_mem = mem_cgroup_get_next_node(next_mem, root_mem);
732 bool mem_cgroup_oom_called(struct task_struct *task)
735 struct mem_cgroup *mem;
736 struct mm_struct *mm;
742 mem = mem_cgroup_from_task(rcu_dereference(mm->owner));
743 if (mem && time_before(jiffies, mem->last_oom_jiffies + HZ/10))
749 * Unlike exported interface, "oom" parameter is added. if oom==true,
750 * oom-killer can be invoked.
752 static int __mem_cgroup_try_charge(struct mm_struct *mm,
753 gfp_t gfp_mask, struct mem_cgroup **memcg,
756 struct mem_cgroup *mem, *mem_over_limit;
757 int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
758 struct res_counter *fail_res;
760 if (unlikely(test_thread_flag(TIF_MEMDIE))) {
761 /* Don't account this! */
767 * We always charge the cgroup the mm_struct belongs to.
768 * The mm_struct's mem_cgroup changes on task migration if the
769 * thread group leader migrates. It's possible that mm is not
770 * set, if so charge the init_mm (happens for pagecache usage).
772 if (likely(!*memcg)) {
774 mem = mem_cgroup_from_task(rcu_dereference(mm->owner));
775 if (unlikely(!mem)) {
780 * For every charge from the cgroup, increment reference count
794 ret = res_counter_charge(&mem->res, PAGE_SIZE, &fail_res);
796 if (!do_swap_account)
798 ret = res_counter_charge(&mem->memsw, PAGE_SIZE,
802 /* mem+swap counter fails */
803 res_counter_uncharge(&mem->res, PAGE_SIZE);
805 mem_over_limit = mem_cgroup_from_res_counter(fail_res,
808 /* mem counter fails */
809 mem_over_limit = mem_cgroup_from_res_counter(fail_res,
812 if (!(gfp_mask & __GFP_WAIT))
815 ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, gfp_mask,
819 * try_to_free_mem_cgroup_pages() might not give us a full
820 * picture of reclaim. Some pages are reclaimed and might be
821 * moved to swap cache or just unmapped from the cgroup.
822 * Check the limit again to see if the reclaim reduced the
823 * current usage of the cgroup before giving up
826 if (mem_cgroup_check_under_limit(mem_over_limit))
831 mutex_lock(&memcg_tasklist);
832 mem_cgroup_out_of_memory(mem_over_limit, gfp_mask);
833 mutex_unlock(&memcg_tasklist);
834 mem_over_limit->last_oom_jiffies = jiffies;
846 * commit a charge got by __mem_cgroup_try_charge() and makes page_cgroup to be
847 * USED state. If already USED, uncharge and return.
850 static void __mem_cgroup_commit_charge(struct mem_cgroup *mem,
851 struct page_cgroup *pc,
852 enum charge_type ctype)
854 /* try_charge() can return NULL to *memcg, taking care of it. */
858 lock_page_cgroup(pc);
859 if (unlikely(PageCgroupUsed(pc))) {
860 unlock_page_cgroup(pc);
861 res_counter_uncharge(&mem->res, PAGE_SIZE);
863 res_counter_uncharge(&mem->memsw, PAGE_SIZE);
867 pc->mem_cgroup = mem;
869 pc->flags = pcg_default_flags[ctype];
871 mem_cgroup_charge_statistics(mem, pc, true);
873 unlock_page_cgroup(pc);
877 * mem_cgroup_move_account - move account of the page
878 * @pc: page_cgroup of the page.
879 * @from: mem_cgroup which the page is moved from.
880 * @to: mem_cgroup which the page is moved to. @from != @to.
882 * The caller must confirm following.
883 * - page is not on LRU (isolate_page() is useful.)
885 * returns 0 at success,
886 * returns -EBUSY when lock is busy or "pc" is unstable.
888 * This function does "uncharge" from old cgroup but doesn't do "charge" to
889 * new cgroup. It should be done by a caller.
892 static int mem_cgroup_move_account(struct page_cgroup *pc,
893 struct mem_cgroup *from, struct mem_cgroup *to)
895 struct mem_cgroup_per_zone *from_mz, *to_mz;
899 VM_BUG_ON(from == to);
900 VM_BUG_ON(PageLRU(pc->page));
902 nid = page_cgroup_nid(pc);
903 zid = page_cgroup_zid(pc);
904 from_mz = mem_cgroup_zoneinfo(from, nid, zid);
905 to_mz = mem_cgroup_zoneinfo(to, nid, zid);
907 if (!trylock_page_cgroup(pc))
910 if (!PageCgroupUsed(pc))
913 if (pc->mem_cgroup != from)
917 res_counter_uncharge(&from->res, PAGE_SIZE);
918 mem_cgroup_charge_statistics(from, pc, false);
920 res_counter_uncharge(&from->memsw, PAGE_SIZE);
922 mem_cgroup_charge_statistics(to, pc, true);
926 unlock_page_cgroup(pc);
931 * move charges to its parent.
934 static int mem_cgroup_move_parent(struct page_cgroup *pc,
935 struct mem_cgroup *child,
938 struct page *page = pc->page;
939 struct cgroup *cg = child->css.cgroup;
940 struct cgroup *pcg = cg->parent;
941 struct mem_cgroup *parent;
949 parent = mem_cgroup_from_cont(pcg);
952 ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false);
956 if (!get_page_unless_zero(page))
959 ret = isolate_lru_page(page);
964 ret = mem_cgroup_move_account(pc, child, parent);
966 /* drop extra refcnt by try_charge() (move_account increment one) */
967 css_put(&parent->css);
968 putback_lru_page(page);
973 /* uncharge if move fails */
975 res_counter_uncharge(&parent->res, PAGE_SIZE);
977 res_counter_uncharge(&parent->memsw, PAGE_SIZE);
983 * Charge the memory controller for page usage.
985 * 0 if the charge was successful
986 * < 0 if the cgroup is over its limit
988 static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
989 gfp_t gfp_mask, enum charge_type ctype,
990 struct mem_cgroup *memcg)
992 struct mem_cgroup *mem;
993 struct page_cgroup *pc;
996 pc = lookup_page_cgroup(page);
997 /* can happen at boot */
1003 ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, true);
1007 __mem_cgroup_commit_charge(mem, pc, ctype);
1011 int mem_cgroup_newpage_charge(struct page *page,
1012 struct mm_struct *mm, gfp_t gfp_mask)
1014 if (mem_cgroup_disabled())
1016 if (PageCompound(page))
1019 * If already mapped, we don't have to account.
1020 * If page cache, page->mapping has address_space.
1021 * But page->mapping may have out-of-use anon_vma pointer,
1022 * detecit it by PageAnon() check. newly-mapped-anon's page->mapping
1025 if (page_mapped(page) || (page->mapping && !PageAnon(page)))
1029 return mem_cgroup_charge_common(page, mm, gfp_mask,
1030 MEM_CGROUP_CHARGE_TYPE_MAPPED, NULL);
1033 int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
1036 if (mem_cgroup_disabled())
1038 if (PageCompound(page))
1041 * Corner case handling. This is called from add_to_page_cache()
1042 * in usual. But some FS (shmem) precharges this page before calling it
1043 * and call add_to_page_cache() with GFP_NOWAIT.
1045 * For GFP_NOWAIT case, the page may be pre-charged before calling
1046 * add_to_page_cache(). (See shmem.c) check it here and avoid to call
1047 * charge twice. (It works but has to pay a bit larger cost.)
1049 if (!(gfp_mask & __GFP_WAIT)) {
1050 struct page_cgroup *pc;
1053 pc = lookup_page_cgroup(page);
1056 lock_page_cgroup(pc);
1057 if (PageCgroupUsed(pc)) {
1058 unlock_page_cgroup(pc);
1061 unlock_page_cgroup(pc);
1067 if (page_is_file_cache(page))
1068 return mem_cgroup_charge_common(page, mm, gfp_mask,
1069 MEM_CGROUP_CHARGE_TYPE_CACHE, NULL);
1071 return mem_cgroup_charge_common(page, mm, gfp_mask,
1072 MEM_CGROUP_CHARGE_TYPE_SHMEM, NULL);
1075 int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
1077 gfp_t mask, struct mem_cgroup **ptr)
1079 struct mem_cgroup *mem;
1082 if (mem_cgroup_disabled())
1085 if (!do_swap_account)
1089 * A racing thread's fault, or swapoff, may have already updated
1090 * the pte, and even removed page from swap cache: return success
1091 * to go on to do_swap_page()'s pte_same() test, which should fail.
1093 if (!PageSwapCache(page))
1096 ent.val = page_private(page);
1098 mem = lookup_swap_cgroup(ent);
1099 if (!mem || mem->obsolete)
1102 return __mem_cgroup_try_charge(NULL, mask, ptr, true);
1106 return __mem_cgroup_try_charge(mm, mask, ptr, true);
1111 int mem_cgroup_cache_charge_swapin(struct page *page,
1112 struct mm_struct *mm, gfp_t mask, bool locked)
1116 if (mem_cgroup_disabled())
1123 * If not locked, the page can be dropped from SwapCache until
1126 if (PageSwapCache(page)) {
1127 struct mem_cgroup *mem = NULL;
1130 ent.val = page_private(page);
1131 if (do_swap_account) {
1132 mem = lookup_swap_cgroup(ent);
1133 if (mem && mem->obsolete)
1138 ret = mem_cgroup_charge_common(page, mm, mask,
1139 MEM_CGROUP_CHARGE_TYPE_SHMEM, mem);
1141 if (!ret && do_swap_account) {
1142 /* avoid double counting */
1143 mem = swap_cgroup_record(ent, NULL);
1145 res_counter_uncharge(&mem->memsw, PAGE_SIZE);
1146 mem_cgroup_put(mem);
1152 /* add this page(page_cgroup) to the LRU we want. */
1153 mem_cgroup_lru_fixup(page);
1159 void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr)
1161 struct page_cgroup *pc;
1163 if (mem_cgroup_disabled())
1167 pc = lookup_page_cgroup(page);
1168 __mem_cgroup_commit_charge(ptr, pc, MEM_CGROUP_CHARGE_TYPE_MAPPED);
1170 * Now swap is on-memory. This means this page may be
1171 * counted both as mem and swap....double count.
1172 * Fix it by uncharging from memsw. This SwapCache is stable
1173 * because we're still under lock_page().
1175 if (do_swap_account) {
1176 swp_entry_t ent = {.val = page_private(page)};
1177 struct mem_cgroup *memcg;
1178 memcg = swap_cgroup_record(ent, NULL);
1180 /* If memcg is obsolete, memcg can be != ptr */
1181 res_counter_uncharge(&memcg->memsw, PAGE_SIZE);
1182 mem_cgroup_put(memcg);
1186 /* add this page(page_cgroup) to the LRU we want. */
1187 mem_cgroup_lru_fixup(page);
1190 void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem)
1192 if (mem_cgroup_disabled())
1196 res_counter_uncharge(&mem->res, PAGE_SIZE);
1197 if (do_swap_account)
1198 res_counter_uncharge(&mem->memsw, PAGE_SIZE);
1204 * uncharge if !page_mapped(page)
1206 static struct mem_cgroup *
1207 __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype)
1209 struct page_cgroup *pc;
1210 struct mem_cgroup *mem = NULL;
1211 struct mem_cgroup_per_zone *mz;
1213 if (mem_cgroup_disabled())
1216 if (PageSwapCache(page))
1220 * Check if our page_cgroup is valid
1222 pc = lookup_page_cgroup(page);
1223 if (unlikely(!pc || !PageCgroupUsed(pc)))
1226 lock_page_cgroup(pc);
1228 mem = pc->mem_cgroup;
1230 if (!PageCgroupUsed(pc))
1234 case MEM_CGROUP_CHARGE_TYPE_MAPPED:
1235 if (page_mapped(page))
1238 case MEM_CGROUP_CHARGE_TYPE_SWAPOUT:
1239 if (!PageAnon(page)) { /* Shared memory */
1240 if (page->mapping && !page_is_file_cache(page))
1242 } else if (page_mapped(page)) /* Anon */
1249 res_counter_uncharge(&mem->res, PAGE_SIZE);
1250 if (do_swap_account && (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT))
1251 res_counter_uncharge(&mem->memsw, PAGE_SIZE);
1253 mem_cgroup_charge_statistics(mem, pc, false);
1254 ClearPageCgroupUsed(pc);
1256 mz = page_cgroup_zoneinfo(pc);
1257 unlock_page_cgroup(pc);
1259 /* at swapout, this memcg will be accessed to record to swap */
1260 if (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT)
1266 unlock_page_cgroup(pc);
1270 void mem_cgroup_uncharge_page(struct page *page)
1273 if (page_mapped(page))
1275 if (page->mapping && !PageAnon(page))
1277 __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED);
1280 void mem_cgroup_uncharge_cache_page(struct page *page)
1282 VM_BUG_ON(page_mapped(page));
1283 VM_BUG_ON(page->mapping);
1284 __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE);
1288 * called from __delete_from_swap_cache() and drop "page" account.
1289 * memcg information is recorded to swap_cgroup of "ent"
1291 void mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent)
1293 struct mem_cgroup *memcg;
1295 memcg = __mem_cgroup_uncharge_common(page,
1296 MEM_CGROUP_CHARGE_TYPE_SWAPOUT);
1297 /* record memcg information */
1298 if (do_swap_account && memcg) {
1299 swap_cgroup_record(ent, memcg);
1300 mem_cgroup_get(memcg);
1303 css_put(&memcg->css);
1306 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1308 * called from swap_entry_free(). remove record in swap_cgroup and
1309 * uncharge "memsw" account.
1311 void mem_cgroup_uncharge_swap(swp_entry_t ent)
1313 struct mem_cgroup *memcg;
1315 if (!do_swap_account)
1318 memcg = swap_cgroup_record(ent, NULL);
1320 res_counter_uncharge(&memcg->memsw, PAGE_SIZE);
1321 mem_cgroup_put(memcg);
1327 * Before starting migration, account PAGE_SIZE to mem_cgroup that the old
1330 int mem_cgroup_prepare_migration(struct page *page, struct mem_cgroup **ptr)
1332 struct page_cgroup *pc;
1333 struct mem_cgroup *mem = NULL;
1336 if (mem_cgroup_disabled())
1339 pc = lookup_page_cgroup(page);
1340 lock_page_cgroup(pc);
1341 if (PageCgroupUsed(pc)) {
1342 mem = pc->mem_cgroup;
1345 unlock_page_cgroup(pc);
1348 ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false);
1355 /* remove redundant charge if migration failed*/
1356 void mem_cgroup_end_migration(struct mem_cgroup *mem,
1357 struct page *oldpage, struct page *newpage)
1359 struct page *target, *unused;
1360 struct page_cgroup *pc;
1361 enum charge_type ctype;
1366 /* at migration success, oldpage->mapping is NULL. */
1367 if (oldpage->mapping) {
1375 if (PageAnon(target))
1376 ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED;
1377 else if (page_is_file_cache(target))
1378 ctype = MEM_CGROUP_CHARGE_TYPE_CACHE;
1380 ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM;
1382 /* unused page is not on radix-tree now. */
1384 __mem_cgroup_uncharge_common(unused, ctype);
1386 pc = lookup_page_cgroup(target);
1388 * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
1389 * So, double-counting is effectively avoided.
1391 __mem_cgroup_commit_charge(mem, pc, ctype);
1394 * Both of oldpage and newpage are still under lock_page().
1395 * Then, we don't have to care about race in radix-tree.
1396 * But we have to be careful that this page is unmapped or not.
1398 * There is a case for !page_mapped(). At the start of
1399 * migration, oldpage was mapped. But now, it's zapped.
1400 * But we know *target* page is not freed/reused under us.
1401 * mem_cgroup_uncharge_page() does all necessary checks.
1403 if (ctype == MEM_CGROUP_CHARGE_TYPE_MAPPED)
1404 mem_cgroup_uncharge_page(target);
1408 * A call to try to shrink memory usage under specified resource controller.
1409 * This is typically used for page reclaiming for shmem for reducing side
1410 * effect of page allocation from shmem, which is used by some mem_cgroup.
1412 int mem_cgroup_shrink_usage(struct mm_struct *mm, gfp_t gfp_mask)
1414 struct mem_cgroup *mem;
1416 int retry = MEM_CGROUP_RECLAIM_RETRIES;
1418 if (mem_cgroup_disabled())
1424 mem = mem_cgroup_from_task(rcu_dereference(mm->owner));
1425 if (unlikely(!mem)) {
1433 progress = mem_cgroup_hierarchical_reclaim(mem, gfp_mask, true);
1434 progress += mem_cgroup_check_under_limit(mem);
1435 } while (!progress && --retry);
1443 static DEFINE_MUTEX(set_limit_mutex);
1445 static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
1446 unsigned long long val)
1449 int retry_count = MEM_CGROUP_RECLAIM_RETRIES;
1454 while (retry_count) {
1455 if (signal_pending(current)) {
1460 * Rather than hide all in some function, I do this in
1461 * open coded manner. You see what this really does.
1462 * We have to guarantee mem->res.limit < mem->memsw.limit.
1464 mutex_lock(&set_limit_mutex);
1465 memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
1466 if (memswlimit < val) {
1468 mutex_unlock(&set_limit_mutex);
1471 ret = res_counter_set_limit(&memcg->res, val);
1472 mutex_unlock(&set_limit_mutex);
1477 progress = mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL,
1479 if (!progress) retry_count--;
1485 int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg,
1486 unsigned long long val)
1488 int retry_count = MEM_CGROUP_RECLAIM_RETRIES;
1489 u64 memlimit, oldusage, curusage;
1492 if (!do_swap_account)
1495 while (retry_count) {
1496 if (signal_pending(current)) {
1501 * Rather than hide all in some function, I do this in
1502 * open coded manner. You see what this really does.
1503 * We have to guarantee mem->res.limit < mem->memsw.limit.
1505 mutex_lock(&set_limit_mutex);
1506 memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT);
1507 if (memlimit > val) {
1509 mutex_unlock(&set_limit_mutex);
1512 ret = res_counter_set_limit(&memcg->memsw, val);
1513 mutex_unlock(&set_limit_mutex);
1518 oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE);
1519 mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL, true);
1520 curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE);
1521 if (curusage >= oldusage)
1528 * This routine traverse page_cgroup in given list and drop them all.
1529 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
1531 static int mem_cgroup_force_empty_list(struct mem_cgroup *mem,
1532 int node, int zid, enum lru_list lru)
1535 struct mem_cgroup_per_zone *mz;
1536 struct page_cgroup *pc, *busy;
1537 unsigned long flags, loop;
1538 struct list_head *list;
1541 zone = &NODE_DATA(node)->node_zones[zid];
1542 mz = mem_cgroup_zoneinfo(mem, node, zid);
1543 list = &mz->lists[lru];
1545 loop = MEM_CGROUP_ZSTAT(mz, lru);
1546 /* give some margin against EBUSY etc...*/
1551 spin_lock_irqsave(&zone->lru_lock, flags);
1552 if (list_empty(list)) {
1553 spin_unlock_irqrestore(&zone->lru_lock, flags);
1556 pc = list_entry(list->prev, struct page_cgroup, lru);
1558 list_move(&pc->lru, list);
1560 spin_unlock_irqrestore(&zone->lru_lock, flags);
1563 spin_unlock_irqrestore(&zone->lru_lock, flags);
1565 ret = mem_cgroup_move_parent(pc, mem, GFP_KERNEL);
1569 if (ret == -EBUSY || ret == -EINVAL) {
1570 /* found lock contention or "pc" is obsolete. */
1577 if (!ret && !list_empty(list))
1583 * make mem_cgroup's charge to be 0 if there is no task.
1584 * This enables deleting this mem_cgroup.
1586 static int mem_cgroup_force_empty(struct mem_cgroup *mem, bool free_all)
1589 int node, zid, shrink;
1590 int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
1591 struct cgroup *cgrp = mem->css.cgroup;
1596 /* should free all ? */
1600 while (mem->res.usage > 0) {
1602 if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children))
1605 if (signal_pending(current))
1607 /* This is for making all *used* pages to be on LRU. */
1608 lru_add_drain_all();
1610 for_each_node_state(node, N_POSSIBLE) {
1611 for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) {
1614 ret = mem_cgroup_force_empty_list(mem,
1623 /* it seems parent cgroup doesn't have enough mem */
1634 /* returns EBUSY if there is a task or if we come here twice. */
1635 if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) {
1639 /* we call try-to-free pages for make this cgroup empty */
1640 lru_add_drain_all();
1641 /* try to free all pages in this cgroup */
1643 while (nr_retries && mem->res.usage > 0) {
1646 if (signal_pending(current)) {
1650 progress = try_to_free_mem_cgroup_pages(mem, GFP_KERNEL,
1651 false, get_swappiness(mem));
1654 /* maybe some writeback is necessary */
1655 congestion_wait(WRITE, HZ/10);
1660 /* try move_account...there may be some *locked* pages. */
1667 int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event)
1669 return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true);
1673 static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft)
1675 return mem_cgroup_from_cont(cont)->use_hierarchy;
1678 static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft,
1682 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
1683 struct cgroup *parent = cont->parent;
1684 struct mem_cgroup *parent_mem = NULL;
1687 parent_mem = mem_cgroup_from_cont(parent);
1691 * If parent's use_hiearchy is set, we can't make any modifications
1692 * in the child subtrees. If it is unset, then the change can
1693 * occur, provided the current cgroup has no children.
1695 * For the root cgroup, parent_mem is NULL, we allow value to be
1696 * set if there are no children.
1698 if ((!parent_mem || !parent_mem->use_hierarchy) &&
1699 (val == 1 || val == 0)) {
1700 if (list_empty(&cont->children))
1701 mem->use_hierarchy = val;
1711 static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft)
1713 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
1717 type = MEMFILE_TYPE(cft->private);
1718 name = MEMFILE_ATTR(cft->private);
1721 val = res_counter_read_u64(&mem->res, name);
1724 if (do_swap_account)
1725 val = res_counter_read_u64(&mem->memsw, name);
1734 * The user of this function is...
1737 static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
1740 struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
1742 unsigned long long val;
1745 type = MEMFILE_TYPE(cft->private);
1746 name = MEMFILE_ATTR(cft->private);
1749 /* This function does all necessary parse...reuse it */
1750 ret = res_counter_memparse_write_strategy(buffer, &val);
1754 ret = mem_cgroup_resize_limit(memcg, val);
1756 ret = mem_cgroup_resize_memsw_limit(memcg, val);
1759 ret = -EINVAL; /* should be BUG() ? */
1765 static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg,
1766 unsigned long long *mem_limit, unsigned long long *memsw_limit)
1768 struct cgroup *cgroup;
1769 unsigned long long min_limit, min_memsw_limit, tmp;
1771 min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT);
1772 min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
1773 cgroup = memcg->css.cgroup;
1774 if (!memcg->use_hierarchy)
1777 while (cgroup->parent) {
1778 cgroup = cgroup->parent;
1779 memcg = mem_cgroup_from_cont(cgroup);
1780 if (!memcg->use_hierarchy)
1782 tmp = res_counter_read_u64(&memcg->res, RES_LIMIT);
1783 min_limit = min(min_limit, tmp);
1784 tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
1785 min_memsw_limit = min(min_memsw_limit, tmp);
1788 *mem_limit = min_limit;
1789 *memsw_limit = min_memsw_limit;
1793 static int mem_cgroup_reset(struct cgroup *cont, unsigned int event)
1795 struct mem_cgroup *mem;
1798 mem = mem_cgroup_from_cont(cont);
1799 type = MEMFILE_TYPE(event);
1800 name = MEMFILE_ATTR(event);
1804 res_counter_reset_max(&mem->res);
1806 res_counter_reset_max(&mem->memsw);
1810 res_counter_reset_failcnt(&mem->res);
1812 res_counter_reset_failcnt(&mem->memsw);
1818 static const struct mem_cgroup_stat_desc {
1821 } mem_cgroup_stat_desc[] = {
1822 [MEM_CGROUP_STAT_CACHE] = { "cache", PAGE_SIZE, },
1823 [MEM_CGROUP_STAT_RSS] = { "rss", PAGE_SIZE, },
1824 [MEM_CGROUP_STAT_PGPGIN_COUNT] = {"pgpgin", 1, },
1825 [MEM_CGROUP_STAT_PGPGOUT_COUNT] = {"pgpgout", 1, },
1828 static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft,
1829 struct cgroup_map_cb *cb)
1831 struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont);
1832 struct mem_cgroup_stat *stat = &mem_cont->stat;
1835 for (i = 0; i < ARRAY_SIZE(stat->cpustat[0].count); i++) {
1838 val = mem_cgroup_read_stat(stat, i);
1839 val *= mem_cgroup_stat_desc[i].unit;
1840 cb->fill(cb, mem_cgroup_stat_desc[i].msg, val);
1842 /* showing # of active pages */
1844 unsigned long active_anon, inactive_anon;
1845 unsigned long active_file, inactive_file;
1846 unsigned long unevictable;
1848 inactive_anon = mem_cgroup_get_all_zonestat(mem_cont,
1850 active_anon = mem_cgroup_get_all_zonestat(mem_cont,
1852 inactive_file = mem_cgroup_get_all_zonestat(mem_cont,
1854 active_file = mem_cgroup_get_all_zonestat(mem_cont,
1856 unevictable = mem_cgroup_get_all_zonestat(mem_cont,
1859 cb->fill(cb, "active_anon", (active_anon) * PAGE_SIZE);
1860 cb->fill(cb, "inactive_anon", (inactive_anon) * PAGE_SIZE);
1861 cb->fill(cb, "active_file", (active_file) * PAGE_SIZE);
1862 cb->fill(cb, "inactive_file", (inactive_file) * PAGE_SIZE);
1863 cb->fill(cb, "unevictable", unevictable * PAGE_SIZE);
1867 unsigned long long limit, memsw_limit;
1868 memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit);
1869 cb->fill(cb, "hierarchical_memory_limit", limit);
1870 if (do_swap_account)
1871 cb->fill(cb, "hierarchical_memsw_limit", memsw_limit);
1874 #ifdef CONFIG_DEBUG_VM
1875 cb->fill(cb, "inactive_ratio", calc_inactive_ratio(mem_cont, NULL));
1879 struct mem_cgroup_per_zone *mz;
1880 unsigned long recent_rotated[2] = {0, 0};
1881 unsigned long recent_scanned[2] = {0, 0};
1883 for_each_online_node(nid)
1884 for (zid = 0; zid < MAX_NR_ZONES; zid++) {
1885 mz = mem_cgroup_zoneinfo(mem_cont, nid, zid);
1887 recent_rotated[0] +=
1888 mz->reclaim_stat.recent_rotated[0];
1889 recent_rotated[1] +=
1890 mz->reclaim_stat.recent_rotated[1];
1891 recent_scanned[0] +=
1892 mz->reclaim_stat.recent_scanned[0];
1893 recent_scanned[1] +=
1894 mz->reclaim_stat.recent_scanned[1];
1896 cb->fill(cb, "recent_rotated_anon", recent_rotated[0]);
1897 cb->fill(cb, "recent_rotated_file", recent_rotated[1]);
1898 cb->fill(cb, "recent_scanned_anon", recent_scanned[0]);
1899 cb->fill(cb, "recent_scanned_file", recent_scanned[1]);
1906 static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft)
1908 struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
1910 return get_swappiness(memcg);
1913 static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft,
1916 struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
1917 struct mem_cgroup *parent;
1921 if (cgrp->parent == NULL)
1924 parent = mem_cgroup_from_cont(cgrp->parent);
1925 /* If under hierarchy, only empty-root can set this value */
1926 if ((parent->use_hierarchy) ||
1927 (memcg->use_hierarchy && !list_empty(&cgrp->children)))
1930 spin_lock(&memcg->reclaim_param_lock);
1931 memcg->swappiness = val;
1932 spin_unlock(&memcg->reclaim_param_lock);
1938 static struct cftype mem_cgroup_files[] = {
1940 .name = "usage_in_bytes",
1941 .private = MEMFILE_PRIVATE(_MEM, RES_USAGE),
1942 .read_u64 = mem_cgroup_read,
1945 .name = "max_usage_in_bytes",
1946 .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE),
1947 .trigger = mem_cgroup_reset,
1948 .read_u64 = mem_cgroup_read,
1951 .name = "limit_in_bytes",
1952 .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT),
1953 .write_string = mem_cgroup_write,
1954 .read_u64 = mem_cgroup_read,
1958 .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT),
1959 .trigger = mem_cgroup_reset,
1960 .read_u64 = mem_cgroup_read,
1964 .read_map = mem_control_stat_show,
1967 .name = "force_empty",
1968 .trigger = mem_cgroup_force_empty_write,
1971 .name = "use_hierarchy",
1972 .write_u64 = mem_cgroup_hierarchy_write,
1973 .read_u64 = mem_cgroup_hierarchy_read,
1976 .name = "swappiness",
1977 .read_u64 = mem_cgroup_swappiness_read,
1978 .write_u64 = mem_cgroup_swappiness_write,
1982 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1983 static struct cftype memsw_cgroup_files[] = {
1985 .name = "memsw.usage_in_bytes",
1986 .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE),
1987 .read_u64 = mem_cgroup_read,
1990 .name = "memsw.max_usage_in_bytes",
1991 .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE),
1992 .trigger = mem_cgroup_reset,
1993 .read_u64 = mem_cgroup_read,
1996 .name = "memsw.limit_in_bytes",
1997 .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT),
1998 .write_string = mem_cgroup_write,
1999 .read_u64 = mem_cgroup_read,
2002 .name = "memsw.failcnt",
2003 .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT),
2004 .trigger = mem_cgroup_reset,
2005 .read_u64 = mem_cgroup_read,
2009 static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss)
2011 if (!do_swap_account)
2013 return cgroup_add_files(cont, ss, memsw_cgroup_files,
2014 ARRAY_SIZE(memsw_cgroup_files));
2017 static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss)
2023 static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
2025 struct mem_cgroup_per_node *pn;
2026 struct mem_cgroup_per_zone *mz;
2028 int zone, tmp = node;
2030 * This routine is called against possible nodes.
2031 * But it's BUG to call kmalloc() against offline node.
2033 * TODO: this routine can waste much memory for nodes which will
2034 * never be onlined. It's better to use memory hotplug callback
2037 if (!node_state(node, N_NORMAL_MEMORY))
2039 pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, tmp);
2043 mem->info.nodeinfo[node] = pn;
2044 memset(pn, 0, sizeof(*pn));
2046 for (zone = 0; zone < MAX_NR_ZONES; zone++) {
2047 mz = &pn->zoneinfo[zone];
2049 INIT_LIST_HEAD(&mz->lists[l]);
2054 static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
2056 kfree(mem->info.nodeinfo[node]);
2059 static int mem_cgroup_size(void)
2061 int cpustat_size = nr_cpu_ids * sizeof(struct mem_cgroup_stat_cpu);
2062 return sizeof(struct mem_cgroup) + cpustat_size;
2065 static struct mem_cgroup *mem_cgroup_alloc(void)
2067 struct mem_cgroup *mem;
2068 int size = mem_cgroup_size();
2070 if (size < PAGE_SIZE)
2071 mem = kmalloc(size, GFP_KERNEL);
2073 mem = vmalloc(size);
2076 memset(mem, 0, size);
2081 * At destroying mem_cgroup, references from swap_cgroup can remain.
2082 * (scanning all at force_empty is too costly...)
2084 * Instead of clearing all references at force_empty, we remember
2085 * the number of reference from swap_cgroup and free mem_cgroup when
2086 * it goes down to 0.
2088 * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and
2089 * entry which points to this memcg will be ignore at swapin.
2091 * Removal of cgroup itself succeeds regardless of refs from swap.
2094 static void mem_cgroup_free(struct mem_cgroup *mem)
2098 if (atomic_read(&mem->refcnt) > 0)
2102 for_each_node_state(node, N_POSSIBLE)
2103 free_mem_cgroup_per_zone_info(mem, node);
2105 if (mem_cgroup_size() < PAGE_SIZE)
2111 static void mem_cgroup_get(struct mem_cgroup *mem)
2113 atomic_inc(&mem->refcnt);
2116 static void mem_cgroup_put(struct mem_cgroup *mem)
2118 if (atomic_dec_and_test(&mem->refcnt)) {
2121 mem_cgroup_free(mem);
2126 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2127 static void __init enable_swap_cgroup(void)
2129 if (!mem_cgroup_disabled() && really_do_swap_account)
2130 do_swap_account = 1;
2133 static void __init enable_swap_cgroup(void)
2138 static struct cgroup_subsys_state *
2139 mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
2141 struct mem_cgroup *mem, *parent;
2144 mem = mem_cgroup_alloc();
2146 return ERR_PTR(-ENOMEM);
2148 for_each_node_state(node, N_POSSIBLE)
2149 if (alloc_mem_cgroup_per_zone_info(mem, node))
2152 if (cont->parent == NULL) {
2153 enable_swap_cgroup();
2156 parent = mem_cgroup_from_cont(cont->parent);
2157 mem->use_hierarchy = parent->use_hierarchy;
2160 if (parent && parent->use_hierarchy) {
2161 res_counter_init(&mem->res, &parent->res);
2162 res_counter_init(&mem->memsw, &parent->memsw);
2164 res_counter_init(&mem->res, NULL);
2165 res_counter_init(&mem->memsw, NULL);
2167 mem->last_scanned_child = NULL;
2168 spin_lock_init(&mem->reclaim_param_lock);
2171 mem->swappiness = get_swappiness(parent);
2175 for_each_node_state(node, N_POSSIBLE)
2176 free_mem_cgroup_per_zone_info(mem, node);
2177 mem_cgroup_free(mem);
2178 return ERR_PTR(-ENOMEM);
2181 static void mem_cgroup_pre_destroy(struct cgroup_subsys *ss,
2182 struct cgroup *cont)
2184 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
2186 mem_cgroup_force_empty(mem, false);
2189 static void mem_cgroup_destroy(struct cgroup_subsys *ss,
2190 struct cgroup *cont)
2192 mem_cgroup_free(mem_cgroup_from_cont(cont));
2195 static int mem_cgroup_populate(struct cgroup_subsys *ss,
2196 struct cgroup *cont)
2200 ret = cgroup_add_files(cont, ss, mem_cgroup_files,
2201 ARRAY_SIZE(mem_cgroup_files));
2204 ret = register_memsw_files(cont, ss);
2208 static void mem_cgroup_move_task(struct cgroup_subsys *ss,
2209 struct cgroup *cont,
2210 struct cgroup *old_cont,
2211 struct task_struct *p)
2213 mutex_lock(&memcg_tasklist);
2215 * FIXME: It's better to move charges of this process from old
2216 * memcg to new memcg. But it's just on TODO-List now.
2218 mutex_unlock(&memcg_tasklist);
2221 struct cgroup_subsys mem_cgroup_subsys = {
2223 .subsys_id = mem_cgroup_subsys_id,
2224 .create = mem_cgroup_create,
2225 .pre_destroy = mem_cgroup_pre_destroy,
2226 .destroy = mem_cgroup_destroy,
2227 .populate = mem_cgroup_populate,
2228 .attach = mem_cgroup_move_task,
2232 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2234 static int __init disable_swap_account(char *s)
2236 really_do_swap_account = 0;
2239 __setup("noswapaccount", disable_swap_account);