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. Basically, this SwapCache is stable
1173 * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page()
1174 * may call delete_from_swap_cache() before reach here.
1176 if (do_swap_account && PageSwapCache(page)) {
1177 swp_entry_t ent = {.val = page_private(page)};
1178 struct mem_cgroup *memcg;
1179 memcg = swap_cgroup_record(ent, NULL);
1181 /* If memcg is obsolete, memcg can be != ptr */
1182 res_counter_uncharge(&memcg->memsw, PAGE_SIZE);
1183 mem_cgroup_put(memcg);
1187 /* add this page(page_cgroup) to the LRU we want. */
1188 mem_cgroup_lru_fixup(page);
1191 void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem)
1193 if (mem_cgroup_disabled())
1197 res_counter_uncharge(&mem->res, PAGE_SIZE);
1198 if (do_swap_account)
1199 res_counter_uncharge(&mem->memsw, PAGE_SIZE);
1205 * uncharge if !page_mapped(page)
1207 static struct mem_cgroup *
1208 __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype)
1210 struct page_cgroup *pc;
1211 struct mem_cgroup *mem = NULL;
1212 struct mem_cgroup_per_zone *mz;
1214 if (mem_cgroup_disabled())
1217 if (PageSwapCache(page))
1221 * Check if our page_cgroup is valid
1223 pc = lookup_page_cgroup(page);
1224 if (unlikely(!pc || !PageCgroupUsed(pc)))
1227 lock_page_cgroup(pc);
1229 mem = pc->mem_cgroup;
1231 if (!PageCgroupUsed(pc))
1235 case MEM_CGROUP_CHARGE_TYPE_MAPPED:
1236 if (page_mapped(page))
1239 case MEM_CGROUP_CHARGE_TYPE_SWAPOUT:
1240 if (!PageAnon(page)) { /* Shared memory */
1241 if (page->mapping && !page_is_file_cache(page))
1243 } else if (page_mapped(page)) /* Anon */
1250 res_counter_uncharge(&mem->res, PAGE_SIZE);
1251 if (do_swap_account && (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT))
1252 res_counter_uncharge(&mem->memsw, PAGE_SIZE);
1254 mem_cgroup_charge_statistics(mem, pc, false);
1255 ClearPageCgroupUsed(pc);
1257 mz = page_cgroup_zoneinfo(pc);
1258 unlock_page_cgroup(pc);
1260 /* at swapout, this memcg will be accessed to record to swap */
1261 if (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT)
1267 unlock_page_cgroup(pc);
1271 void mem_cgroup_uncharge_page(struct page *page)
1274 if (page_mapped(page))
1276 if (page->mapping && !PageAnon(page))
1278 __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED);
1281 void mem_cgroup_uncharge_cache_page(struct page *page)
1283 VM_BUG_ON(page_mapped(page));
1284 VM_BUG_ON(page->mapping);
1285 __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE);
1289 * called from __delete_from_swap_cache() and drop "page" account.
1290 * memcg information is recorded to swap_cgroup of "ent"
1292 void mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent)
1294 struct mem_cgroup *memcg;
1296 memcg = __mem_cgroup_uncharge_common(page,
1297 MEM_CGROUP_CHARGE_TYPE_SWAPOUT);
1298 /* record memcg information */
1299 if (do_swap_account && memcg) {
1300 swap_cgroup_record(ent, memcg);
1301 mem_cgroup_get(memcg);
1304 css_put(&memcg->css);
1307 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1309 * called from swap_entry_free(). remove record in swap_cgroup and
1310 * uncharge "memsw" account.
1312 void mem_cgroup_uncharge_swap(swp_entry_t ent)
1314 struct mem_cgroup *memcg;
1316 if (!do_swap_account)
1319 memcg = swap_cgroup_record(ent, NULL);
1321 res_counter_uncharge(&memcg->memsw, PAGE_SIZE);
1322 mem_cgroup_put(memcg);
1328 * Before starting migration, account PAGE_SIZE to mem_cgroup that the old
1331 int mem_cgroup_prepare_migration(struct page *page, struct mem_cgroup **ptr)
1333 struct page_cgroup *pc;
1334 struct mem_cgroup *mem = NULL;
1337 if (mem_cgroup_disabled())
1340 pc = lookup_page_cgroup(page);
1341 lock_page_cgroup(pc);
1342 if (PageCgroupUsed(pc)) {
1343 mem = pc->mem_cgroup;
1346 unlock_page_cgroup(pc);
1349 ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false);
1356 /* remove redundant charge if migration failed*/
1357 void mem_cgroup_end_migration(struct mem_cgroup *mem,
1358 struct page *oldpage, struct page *newpage)
1360 struct page *target, *unused;
1361 struct page_cgroup *pc;
1362 enum charge_type ctype;
1367 /* at migration success, oldpage->mapping is NULL. */
1368 if (oldpage->mapping) {
1376 if (PageAnon(target))
1377 ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED;
1378 else if (page_is_file_cache(target))
1379 ctype = MEM_CGROUP_CHARGE_TYPE_CACHE;
1381 ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM;
1383 /* unused page is not on radix-tree now. */
1385 __mem_cgroup_uncharge_common(unused, ctype);
1387 pc = lookup_page_cgroup(target);
1389 * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
1390 * So, double-counting is effectively avoided.
1392 __mem_cgroup_commit_charge(mem, pc, ctype);
1395 * Both of oldpage and newpage are still under lock_page().
1396 * Then, we don't have to care about race in radix-tree.
1397 * But we have to be careful that this page is unmapped or not.
1399 * There is a case for !page_mapped(). At the start of
1400 * migration, oldpage was mapped. But now, it's zapped.
1401 * But we know *target* page is not freed/reused under us.
1402 * mem_cgroup_uncharge_page() does all necessary checks.
1404 if (ctype == MEM_CGROUP_CHARGE_TYPE_MAPPED)
1405 mem_cgroup_uncharge_page(target);
1409 * A call to try to shrink memory usage under specified resource controller.
1410 * This is typically used for page reclaiming for shmem for reducing side
1411 * effect of page allocation from shmem, which is used by some mem_cgroup.
1413 int mem_cgroup_shrink_usage(struct mm_struct *mm, gfp_t gfp_mask)
1415 struct mem_cgroup *mem;
1417 int retry = MEM_CGROUP_RECLAIM_RETRIES;
1419 if (mem_cgroup_disabled())
1425 mem = mem_cgroup_from_task(rcu_dereference(mm->owner));
1426 if (unlikely(!mem)) {
1434 progress = mem_cgroup_hierarchical_reclaim(mem, gfp_mask, true);
1435 progress += mem_cgroup_check_under_limit(mem);
1436 } while (!progress && --retry);
1444 static DEFINE_MUTEX(set_limit_mutex);
1446 static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
1447 unsigned long long val)
1450 int retry_count = MEM_CGROUP_RECLAIM_RETRIES;
1455 while (retry_count) {
1456 if (signal_pending(current)) {
1461 * Rather than hide all in some function, I do this in
1462 * open coded manner. You see what this really does.
1463 * We have to guarantee mem->res.limit < mem->memsw.limit.
1465 mutex_lock(&set_limit_mutex);
1466 memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
1467 if (memswlimit < val) {
1469 mutex_unlock(&set_limit_mutex);
1472 ret = res_counter_set_limit(&memcg->res, val);
1473 mutex_unlock(&set_limit_mutex);
1478 progress = mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL,
1480 if (!progress) retry_count--;
1486 int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg,
1487 unsigned long long val)
1489 int retry_count = MEM_CGROUP_RECLAIM_RETRIES;
1490 u64 memlimit, oldusage, curusage;
1493 if (!do_swap_account)
1496 while (retry_count) {
1497 if (signal_pending(current)) {
1502 * Rather than hide all in some function, I do this in
1503 * open coded manner. You see what this really does.
1504 * We have to guarantee mem->res.limit < mem->memsw.limit.
1506 mutex_lock(&set_limit_mutex);
1507 memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT);
1508 if (memlimit > val) {
1510 mutex_unlock(&set_limit_mutex);
1513 ret = res_counter_set_limit(&memcg->memsw, val);
1514 mutex_unlock(&set_limit_mutex);
1519 oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE);
1520 mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL, true);
1521 curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE);
1522 if (curusage >= oldusage)
1529 * This routine traverse page_cgroup in given list and drop them all.
1530 * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
1532 static int mem_cgroup_force_empty_list(struct mem_cgroup *mem,
1533 int node, int zid, enum lru_list lru)
1536 struct mem_cgroup_per_zone *mz;
1537 struct page_cgroup *pc, *busy;
1538 unsigned long flags, loop;
1539 struct list_head *list;
1542 zone = &NODE_DATA(node)->node_zones[zid];
1543 mz = mem_cgroup_zoneinfo(mem, node, zid);
1544 list = &mz->lists[lru];
1546 loop = MEM_CGROUP_ZSTAT(mz, lru);
1547 /* give some margin against EBUSY etc...*/
1552 spin_lock_irqsave(&zone->lru_lock, flags);
1553 if (list_empty(list)) {
1554 spin_unlock_irqrestore(&zone->lru_lock, flags);
1557 pc = list_entry(list->prev, struct page_cgroup, lru);
1559 list_move(&pc->lru, list);
1561 spin_unlock_irqrestore(&zone->lru_lock, flags);
1564 spin_unlock_irqrestore(&zone->lru_lock, flags);
1566 ret = mem_cgroup_move_parent(pc, mem, GFP_KERNEL);
1570 if (ret == -EBUSY || ret == -EINVAL) {
1571 /* found lock contention or "pc" is obsolete. */
1578 if (!ret && !list_empty(list))
1584 * make mem_cgroup's charge to be 0 if there is no task.
1585 * This enables deleting this mem_cgroup.
1587 static int mem_cgroup_force_empty(struct mem_cgroup *mem, bool free_all)
1590 int node, zid, shrink;
1591 int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
1592 struct cgroup *cgrp = mem->css.cgroup;
1597 /* should free all ? */
1601 while (mem->res.usage > 0) {
1603 if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children))
1606 if (signal_pending(current))
1608 /* This is for making all *used* pages to be on LRU. */
1609 lru_add_drain_all();
1611 for_each_node_state(node, N_POSSIBLE) {
1612 for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) {
1615 ret = mem_cgroup_force_empty_list(mem,
1624 /* it seems parent cgroup doesn't have enough mem */
1635 /* returns EBUSY if there is a task or if we come here twice. */
1636 if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) {
1640 /* we call try-to-free pages for make this cgroup empty */
1641 lru_add_drain_all();
1642 /* try to free all pages in this cgroup */
1644 while (nr_retries && mem->res.usage > 0) {
1647 if (signal_pending(current)) {
1651 progress = try_to_free_mem_cgroup_pages(mem, GFP_KERNEL,
1652 false, get_swappiness(mem));
1655 /* maybe some writeback is necessary */
1656 congestion_wait(WRITE, HZ/10);
1661 /* try move_account...there may be some *locked* pages. */
1668 int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event)
1670 return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true);
1674 static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft)
1676 return mem_cgroup_from_cont(cont)->use_hierarchy;
1679 static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft,
1683 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
1684 struct cgroup *parent = cont->parent;
1685 struct mem_cgroup *parent_mem = NULL;
1688 parent_mem = mem_cgroup_from_cont(parent);
1692 * If parent's use_hiearchy is set, we can't make any modifications
1693 * in the child subtrees. If it is unset, then the change can
1694 * occur, provided the current cgroup has no children.
1696 * For the root cgroup, parent_mem is NULL, we allow value to be
1697 * set if there are no children.
1699 if ((!parent_mem || !parent_mem->use_hierarchy) &&
1700 (val == 1 || val == 0)) {
1701 if (list_empty(&cont->children))
1702 mem->use_hierarchy = val;
1712 static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft)
1714 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
1718 type = MEMFILE_TYPE(cft->private);
1719 name = MEMFILE_ATTR(cft->private);
1722 val = res_counter_read_u64(&mem->res, name);
1725 if (do_swap_account)
1726 val = res_counter_read_u64(&mem->memsw, name);
1735 * The user of this function is...
1738 static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
1741 struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
1743 unsigned long long val;
1746 type = MEMFILE_TYPE(cft->private);
1747 name = MEMFILE_ATTR(cft->private);
1750 /* This function does all necessary parse...reuse it */
1751 ret = res_counter_memparse_write_strategy(buffer, &val);
1755 ret = mem_cgroup_resize_limit(memcg, val);
1757 ret = mem_cgroup_resize_memsw_limit(memcg, val);
1760 ret = -EINVAL; /* should be BUG() ? */
1766 static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg,
1767 unsigned long long *mem_limit, unsigned long long *memsw_limit)
1769 struct cgroup *cgroup;
1770 unsigned long long min_limit, min_memsw_limit, tmp;
1772 min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT);
1773 min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
1774 cgroup = memcg->css.cgroup;
1775 if (!memcg->use_hierarchy)
1778 while (cgroup->parent) {
1779 cgroup = cgroup->parent;
1780 memcg = mem_cgroup_from_cont(cgroup);
1781 if (!memcg->use_hierarchy)
1783 tmp = res_counter_read_u64(&memcg->res, RES_LIMIT);
1784 min_limit = min(min_limit, tmp);
1785 tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
1786 min_memsw_limit = min(min_memsw_limit, tmp);
1789 *mem_limit = min_limit;
1790 *memsw_limit = min_memsw_limit;
1794 static int mem_cgroup_reset(struct cgroup *cont, unsigned int event)
1796 struct mem_cgroup *mem;
1799 mem = mem_cgroup_from_cont(cont);
1800 type = MEMFILE_TYPE(event);
1801 name = MEMFILE_ATTR(event);
1805 res_counter_reset_max(&mem->res);
1807 res_counter_reset_max(&mem->memsw);
1811 res_counter_reset_failcnt(&mem->res);
1813 res_counter_reset_failcnt(&mem->memsw);
1819 static const struct mem_cgroup_stat_desc {
1822 } mem_cgroup_stat_desc[] = {
1823 [MEM_CGROUP_STAT_CACHE] = { "cache", PAGE_SIZE, },
1824 [MEM_CGROUP_STAT_RSS] = { "rss", PAGE_SIZE, },
1825 [MEM_CGROUP_STAT_PGPGIN_COUNT] = {"pgpgin", 1, },
1826 [MEM_CGROUP_STAT_PGPGOUT_COUNT] = {"pgpgout", 1, },
1829 static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft,
1830 struct cgroup_map_cb *cb)
1832 struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont);
1833 struct mem_cgroup_stat *stat = &mem_cont->stat;
1836 for (i = 0; i < ARRAY_SIZE(stat->cpustat[0].count); i++) {
1839 val = mem_cgroup_read_stat(stat, i);
1840 val *= mem_cgroup_stat_desc[i].unit;
1841 cb->fill(cb, mem_cgroup_stat_desc[i].msg, val);
1843 /* showing # of active pages */
1845 unsigned long active_anon, inactive_anon;
1846 unsigned long active_file, inactive_file;
1847 unsigned long unevictable;
1849 inactive_anon = mem_cgroup_get_all_zonestat(mem_cont,
1851 active_anon = mem_cgroup_get_all_zonestat(mem_cont,
1853 inactive_file = mem_cgroup_get_all_zonestat(mem_cont,
1855 active_file = mem_cgroup_get_all_zonestat(mem_cont,
1857 unevictable = mem_cgroup_get_all_zonestat(mem_cont,
1860 cb->fill(cb, "active_anon", (active_anon) * PAGE_SIZE);
1861 cb->fill(cb, "inactive_anon", (inactive_anon) * PAGE_SIZE);
1862 cb->fill(cb, "active_file", (active_file) * PAGE_SIZE);
1863 cb->fill(cb, "inactive_file", (inactive_file) * PAGE_SIZE);
1864 cb->fill(cb, "unevictable", unevictable * PAGE_SIZE);
1868 unsigned long long limit, memsw_limit;
1869 memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit);
1870 cb->fill(cb, "hierarchical_memory_limit", limit);
1871 if (do_swap_account)
1872 cb->fill(cb, "hierarchical_memsw_limit", memsw_limit);
1875 #ifdef CONFIG_DEBUG_VM
1876 cb->fill(cb, "inactive_ratio", calc_inactive_ratio(mem_cont, NULL));
1880 struct mem_cgroup_per_zone *mz;
1881 unsigned long recent_rotated[2] = {0, 0};
1882 unsigned long recent_scanned[2] = {0, 0};
1884 for_each_online_node(nid)
1885 for (zid = 0; zid < MAX_NR_ZONES; zid++) {
1886 mz = mem_cgroup_zoneinfo(mem_cont, nid, zid);
1888 recent_rotated[0] +=
1889 mz->reclaim_stat.recent_rotated[0];
1890 recent_rotated[1] +=
1891 mz->reclaim_stat.recent_rotated[1];
1892 recent_scanned[0] +=
1893 mz->reclaim_stat.recent_scanned[0];
1894 recent_scanned[1] +=
1895 mz->reclaim_stat.recent_scanned[1];
1897 cb->fill(cb, "recent_rotated_anon", recent_rotated[0]);
1898 cb->fill(cb, "recent_rotated_file", recent_rotated[1]);
1899 cb->fill(cb, "recent_scanned_anon", recent_scanned[0]);
1900 cb->fill(cb, "recent_scanned_file", recent_scanned[1]);
1907 static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft)
1909 struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
1911 return get_swappiness(memcg);
1914 static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft,
1917 struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
1918 struct mem_cgroup *parent;
1922 if (cgrp->parent == NULL)
1925 parent = mem_cgroup_from_cont(cgrp->parent);
1926 /* If under hierarchy, only empty-root can set this value */
1927 if ((parent->use_hierarchy) ||
1928 (memcg->use_hierarchy && !list_empty(&cgrp->children)))
1931 spin_lock(&memcg->reclaim_param_lock);
1932 memcg->swappiness = val;
1933 spin_unlock(&memcg->reclaim_param_lock);
1939 static struct cftype mem_cgroup_files[] = {
1941 .name = "usage_in_bytes",
1942 .private = MEMFILE_PRIVATE(_MEM, RES_USAGE),
1943 .read_u64 = mem_cgroup_read,
1946 .name = "max_usage_in_bytes",
1947 .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE),
1948 .trigger = mem_cgroup_reset,
1949 .read_u64 = mem_cgroup_read,
1952 .name = "limit_in_bytes",
1953 .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT),
1954 .write_string = mem_cgroup_write,
1955 .read_u64 = mem_cgroup_read,
1959 .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT),
1960 .trigger = mem_cgroup_reset,
1961 .read_u64 = mem_cgroup_read,
1965 .read_map = mem_control_stat_show,
1968 .name = "force_empty",
1969 .trigger = mem_cgroup_force_empty_write,
1972 .name = "use_hierarchy",
1973 .write_u64 = mem_cgroup_hierarchy_write,
1974 .read_u64 = mem_cgroup_hierarchy_read,
1977 .name = "swappiness",
1978 .read_u64 = mem_cgroup_swappiness_read,
1979 .write_u64 = mem_cgroup_swappiness_write,
1983 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
1984 static struct cftype memsw_cgroup_files[] = {
1986 .name = "memsw.usage_in_bytes",
1987 .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE),
1988 .read_u64 = mem_cgroup_read,
1991 .name = "memsw.max_usage_in_bytes",
1992 .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE),
1993 .trigger = mem_cgroup_reset,
1994 .read_u64 = mem_cgroup_read,
1997 .name = "memsw.limit_in_bytes",
1998 .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT),
1999 .write_string = mem_cgroup_write,
2000 .read_u64 = mem_cgroup_read,
2003 .name = "memsw.failcnt",
2004 .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT),
2005 .trigger = mem_cgroup_reset,
2006 .read_u64 = mem_cgroup_read,
2010 static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss)
2012 if (!do_swap_account)
2014 return cgroup_add_files(cont, ss, memsw_cgroup_files,
2015 ARRAY_SIZE(memsw_cgroup_files));
2018 static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss)
2024 static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
2026 struct mem_cgroup_per_node *pn;
2027 struct mem_cgroup_per_zone *mz;
2029 int zone, tmp = node;
2031 * This routine is called against possible nodes.
2032 * But it's BUG to call kmalloc() against offline node.
2034 * TODO: this routine can waste much memory for nodes which will
2035 * never be onlined. It's better to use memory hotplug callback
2038 if (!node_state(node, N_NORMAL_MEMORY))
2040 pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, tmp);
2044 mem->info.nodeinfo[node] = pn;
2045 memset(pn, 0, sizeof(*pn));
2047 for (zone = 0; zone < MAX_NR_ZONES; zone++) {
2048 mz = &pn->zoneinfo[zone];
2050 INIT_LIST_HEAD(&mz->lists[l]);
2055 static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
2057 kfree(mem->info.nodeinfo[node]);
2060 static int mem_cgroup_size(void)
2062 int cpustat_size = nr_cpu_ids * sizeof(struct mem_cgroup_stat_cpu);
2063 return sizeof(struct mem_cgroup) + cpustat_size;
2066 static struct mem_cgroup *mem_cgroup_alloc(void)
2068 struct mem_cgroup *mem;
2069 int size = mem_cgroup_size();
2071 if (size < PAGE_SIZE)
2072 mem = kmalloc(size, GFP_KERNEL);
2074 mem = vmalloc(size);
2077 memset(mem, 0, size);
2082 * At destroying mem_cgroup, references from swap_cgroup can remain.
2083 * (scanning all at force_empty is too costly...)
2085 * Instead of clearing all references at force_empty, we remember
2086 * the number of reference from swap_cgroup and free mem_cgroup when
2087 * it goes down to 0.
2089 * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and
2090 * entry which points to this memcg will be ignore at swapin.
2092 * Removal of cgroup itself succeeds regardless of refs from swap.
2095 static void mem_cgroup_free(struct mem_cgroup *mem)
2099 if (atomic_read(&mem->refcnt) > 0)
2103 for_each_node_state(node, N_POSSIBLE)
2104 free_mem_cgroup_per_zone_info(mem, node);
2106 if (mem_cgroup_size() < PAGE_SIZE)
2112 static void mem_cgroup_get(struct mem_cgroup *mem)
2114 atomic_inc(&mem->refcnt);
2117 static void mem_cgroup_put(struct mem_cgroup *mem)
2119 if (atomic_dec_and_test(&mem->refcnt)) {
2122 mem_cgroup_free(mem);
2127 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2128 static void __init enable_swap_cgroup(void)
2130 if (!mem_cgroup_disabled() && really_do_swap_account)
2131 do_swap_account = 1;
2134 static void __init enable_swap_cgroup(void)
2139 static struct cgroup_subsys_state *
2140 mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
2142 struct mem_cgroup *mem, *parent;
2145 mem = mem_cgroup_alloc();
2147 return ERR_PTR(-ENOMEM);
2149 for_each_node_state(node, N_POSSIBLE)
2150 if (alloc_mem_cgroup_per_zone_info(mem, node))
2153 if (cont->parent == NULL) {
2154 enable_swap_cgroup();
2157 parent = mem_cgroup_from_cont(cont->parent);
2158 mem->use_hierarchy = parent->use_hierarchy;
2161 if (parent && parent->use_hierarchy) {
2162 res_counter_init(&mem->res, &parent->res);
2163 res_counter_init(&mem->memsw, &parent->memsw);
2165 res_counter_init(&mem->res, NULL);
2166 res_counter_init(&mem->memsw, NULL);
2168 mem->last_scanned_child = NULL;
2169 spin_lock_init(&mem->reclaim_param_lock);
2172 mem->swappiness = get_swappiness(parent);
2176 for_each_node_state(node, N_POSSIBLE)
2177 free_mem_cgroup_per_zone_info(mem, node);
2178 mem_cgroup_free(mem);
2179 return ERR_PTR(-ENOMEM);
2182 static void mem_cgroup_pre_destroy(struct cgroup_subsys *ss,
2183 struct cgroup *cont)
2185 struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
2187 mem_cgroup_force_empty(mem, false);
2190 static void mem_cgroup_destroy(struct cgroup_subsys *ss,
2191 struct cgroup *cont)
2193 mem_cgroup_free(mem_cgroup_from_cont(cont));
2196 static int mem_cgroup_populate(struct cgroup_subsys *ss,
2197 struct cgroup *cont)
2201 ret = cgroup_add_files(cont, ss, mem_cgroup_files,
2202 ARRAY_SIZE(mem_cgroup_files));
2205 ret = register_memsw_files(cont, ss);
2209 static void mem_cgroup_move_task(struct cgroup_subsys *ss,
2210 struct cgroup *cont,
2211 struct cgroup *old_cont,
2212 struct task_struct *p)
2214 mutex_lock(&memcg_tasklist);
2216 * FIXME: It's better to move charges of this process from old
2217 * memcg to new memcg. But it's just on TODO-List now.
2219 mutex_unlock(&memcg_tasklist);
2222 struct cgroup_subsys mem_cgroup_subsys = {
2224 .subsys_id = mem_cgroup_subsys_id,
2225 .create = mem_cgroup_create,
2226 .pre_destroy = mem_cgroup_pre_destroy,
2227 .destroy = mem_cgroup_destroy,
2228 .populate = mem_cgroup_populate,
2229 .attach = mem_cgroup_move_task,
2233 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
2235 static int __init disable_swap_account(char *s)
2237 really_do_swap_account = 0;
2240 __setup("noswapaccount", disable_swap_account);