X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=mm%2Fmemcontrol.c;h=fd4529d86de59cbfc7093a433752e9b9b604dc93;hb=64f1607ffbbc772685733ea63e6f7f4183df1b16;hp=886e2224c5fdde439cb99da510159065e545b796;hpb=18f59ea7de08db2449ba99185e8d8cc30e7acac5;p=safe%2Fjmp%2Flinux-2.6 diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 886e222..fd4529d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include @@ -44,13 +45,14 @@ struct cgroup_subsys mem_cgroup_subsys __read_mostly; #define MEM_CGROUP_RECLAIM_RETRIES 5 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP -/* Turned on only when memory cgroup is enabled && really_do_swap_account = 0 */ +/* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */ int do_swap_account __read_mostly; static int really_do_swap_account __initdata = 1; /* for remember boot option*/ #else #define do_swap_account (0) #endif +static DEFINE_MUTEX(memcg_tasklist); /* can be hold under cgroup_mutex */ /* * Statistics for memory cgroup. @@ -60,7 +62,8 @@ enum mem_cgroup_stat_index { * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss. */ MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */ - MEM_CGROUP_STAT_RSS, /* # of pages charged as rss */ + MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */ + MEM_CGROUP_STAT_MAPPED_FILE, /* # of pages charged as file rss */ MEM_CGROUP_STAT_PGPGIN_COUNT, /* # of pages paged in */ MEM_CGROUP_STAT_PGPGOUT_COUNT, /* # of pages paged out */ @@ -94,6 +97,15 @@ static s64 mem_cgroup_read_stat(struct mem_cgroup_stat *stat, return ret; } +static s64 mem_cgroup_local_usage(struct mem_cgroup_stat *stat) +{ + s64 ret; + + ret = mem_cgroup_read_stat(stat, MEM_CGROUP_STAT_CACHE); + ret += mem_cgroup_read_stat(stat, MEM_CGROUP_STAT_RSS); + return ret; +} + /* * per-zone information in memory controller. */ @@ -103,6 +115,8 @@ struct mem_cgroup_per_zone { */ struct list_head lists[NR_LRU_LISTS]; unsigned long count[NR_LRU_LISTS]; + + struct zone_reclaim_stat reclaim_stat; }; /* Macro for accessing counter */ #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)]) @@ -142,20 +156,30 @@ struct mem_cgroup { */ struct mem_cgroup_lru_info info; + /* + protect against reclaim related member. + */ + spinlock_t reclaim_param_lock; + int prev_priority; /* for recording reclaim priority */ /* * While reclaiming in a hiearchy, we cache the last child we - * reclaimed from. Protected by cgroup_lock() + * reclaimed from. */ - struct mem_cgroup *last_scanned_child; + int last_scanned_child; /* * Should the accounting and control be hierarchical, per subtree? */ bool use_hierarchy; - - int obsolete; + unsigned long last_oom_jiffies; atomic_t refcnt; + + unsigned int swappiness; + + /* set when res.limit == memsw.limit */ + bool memsw_is_minimum; + /* * statistics. This must be placed at the end of memcg. */ @@ -168,6 +192,7 @@ enum charge_type { MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ + MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ NR_CHARGE_TYPE, }; @@ -183,7 +208,6 @@ pcg_default_flags[NR_CHARGE_TYPE] = { 0, /* FORCE */ }; - /* for encoding cft->private value on file */ #define _MEM (0) #define _MEMSWAP (1) @@ -193,6 +217,7 @@ pcg_default_flags[NR_CHARGE_TYPE] = { static void mem_cgroup_get(struct mem_cgroup *mem); static void mem_cgroup_put(struct mem_cgroup *mem); +static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem); static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, struct page_cgroup *pc, @@ -231,10 +256,13 @@ page_cgroup_zoneinfo(struct page_cgroup *pc) int nid = page_cgroup_nid(pc); int zid = page_cgroup_zid(pc); + if (!mem) + return NULL; + return mem_cgroup_zoneinfo(mem, nid, zid); } -static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup *mem, +static unsigned long mem_cgroup_get_local_zonestat(struct mem_cgroup *mem, enum lru_list idx) { int nid, zid; @@ -270,6 +298,62 @@ struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) struct mem_cgroup, css); } +static struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) +{ + struct mem_cgroup *mem = NULL; + + if (!mm) + return NULL; + /* + * Because we have no locks, mm->owner's may be being moved to other + * cgroup. We use css_tryget() here even if this looks + * pessimistic (rather than adding locks here). + */ + rcu_read_lock(); + do { + mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); + if (unlikely(!mem)) + break; + } while (!css_tryget(&mem->css)); + rcu_read_unlock(); + return mem; +} + +/* + * Call callback function against all cgroup under hierarchy tree. + */ +static int mem_cgroup_walk_tree(struct mem_cgroup *root, void *data, + int (*func)(struct mem_cgroup *, void *)) +{ + int found, ret, nextid; + struct cgroup_subsys_state *css; + struct mem_cgroup *mem; + + if (!root->use_hierarchy) + return (*func)(root, data); + + nextid = 1; + do { + ret = 0; + mem = NULL; + + rcu_read_lock(); + css = css_get_next(&mem_cgroup_subsys, nextid, &root->css, + &found); + if (css && css_tryget(css)) + mem = container_of(css, struct mem_cgroup, css); + rcu_read_unlock(); + + if (mem) { + ret = (*func)(mem, data); + css_put(&mem->css); + } + nextid = found + 1; + } while (!ret && css); + + return ret; +} + /* * Following LRU functions are allowed to be used without PCG_LOCK. * Operations are called by routine of global LRU independently from memcg. @@ -294,8 +378,12 @@ void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru) return; pc = lookup_page_cgroup(page); /* can happen while we handle swapcache. */ - if (list_empty(&pc->lru)) + if (list_empty(&pc->lru) || !pc->mem_cgroup) return; + /* + * We don't check PCG_USED bit. It's cleared when the "page" is finally + * removed from global LRU. + */ mz = page_cgroup_zoneinfo(pc); mem = pc->mem_cgroup; MEM_CGROUP_ZSTAT(mz, lru) -= 1; @@ -317,6 +405,10 @@ void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru) return; pc = lookup_page_cgroup(page); + /* + * Used bit is set without atomic ops but after smp_wmb(). + * For making pc->mem_cgroup visible, insert smp_rmb() here. + */ smp_rmb(); /* unused page is not rotated. */ if (!PageCgroupUsed(pc)) @@ -333,7 +425,10 @@ void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru) if (mem_cgroup_disabled()) return; pc = lookup_page_cgroup(page); - /* barrier to sync with "charge" */ + /* + * Used bit is set without atomic ops but after smp_wmb(). + * For making pc->mem_cgroup visible, insert smp_rmb() here. + */ smp_rmb(); if (!PageCgroupUsed(pc)) return; @@ -342,16 +437,44 @@ void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru) MEM_CGROUP_ZSTAT(mz, lru) += 1; list_add(&pc->lru, &mz->lists[lru]); } + /* - * To add swapcache into LRU. Be careful to all this function. - * zone->lru_lock shouldn't be held and irq must not be disabled. + * At handling SwapCache, pc->mem_cgroup may be changed while it's linked to + * lru because the page may.be reused after it's fully uncharged (because of + * SwapCache behavior).To handle that, unlink page_cgroup from LRU when charge + * it again. This function is only used to charge SwapCache. It's done under + * lock_page and expected that zone->lru_lock is never held. */ -static void mem_cgroup_lru_fixup(struct page *page) +static void mem_cgroup_lru_del_before_commit_swapcache(struct page *page) +{ + unsigned long flags; + struct zone *zone = page_zone(page); + struct page_cgroup *pc = lookup_page_cgroup(page); + + spin_lock_irqsave(&zone->lru_lock, flags); + /* + * Forget old LRU when this page_cgroup is *not* used. This Used bit + * is guarded by lock_page() because the page is SwapCache. + */ + if (!PageCgroupUsed(pc)) + mem_cgroup_del_lru_list(page, page_lru(page)); + spin_unlock_irqrestore(&zone->lru_lock, flags); +} + +static void mem_cgroup_lru_add_after_commit_swapcache(struct page *page) { - if (!isolate_lru_page(page)) - putback_lru_page(page); + unsigned long flags; + struct zone *zone = page_zone(page); + struct page_cgroup *pc = lookup_page_cgroup(page); + + spin_lock_irqsave(&zone->lru_lock, flags); + /* link when the page is linked to LRU but page_cgroup isn't */ + if (PageLRU(page) && list_empty(&pc->lru)) + mem_cgroup_add_lru_list(page, page_lru(page)); + spin_unlock_irqrestore(&zone->lru_lock, flags); } + void mem_cgroup_move_lists(struct page *page, enum lru_list from, enum lru_list to) { @@ -364,68 +487,149 @@ void mem_cgroup_move_lists(struct page *page, int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem) { int ret; + struct mem_cgroup *curr = NULL; task_lock(task); - ret = task->mm && mm_match_cgroup(task->mm, mem); + rcu_read_lock(); + curr = try_get_mem_cgroup_from_mm(task->mm); + rcu_read_unlock(); task_unlock(task); + if (!curr) + return 0; + if (curr->use_hierarchy) + ret = css_is_ancestor(&curr->css, &mem->css); + else + ret = (curr == mem); + css_put(&curr->css); return ret; } /* - * Calculate mapped_ratio under memory controller. This will be used in - * vmscan.c for deteremining we have to reclaim mapped pages. - */ -int mem_cgroup_calc_mapped_ratio(struct mem_cgroup *mem) -{ - long total, rss; - - /* - * usage is recorded in bytes. But, here, we assume the number of - * physical pages can be represented by "long" on any arch. - */ - total = (long) (mem->res.usage >> PAGE_SHIFT) + 1L; - rss = (long)mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_RSS); - return (int)((rss * 100L) / total); -} - -/* * prev_priority control...this will be used in memory reclaim path. */ int mem_cgroup_get_reclaim_priority(struct mem_cgroup *mem) { - return mem->prev_priority; + int prev_priority; + + spin_lock(&mem->reclaim_param_lock); + prev_priority = mem->prev_priority; + spin_unlock(&mem->reclaim_param_lock); + + return prev_priority; } void mem_cgroup_note_reclaim_priority(struct mem_cgroup *mem, int priority) { + spin_lock(&mem->reclaim_param_lock); if (priority < mem->prev_priority) mem->prev_priority = priority; + spin_unlock(&mem->reclaim_param_lock); } void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, int priority) { + spin_lock(&mem->reclaim_param_lock); mem->prev_priority = priority; + spin_unlock(&mem->reclaim_param_lock); } -/* - * Calculate # of pages to be scanned in this priority/zone. - * See also vmscan.c - * - * priority starts from "DEF_PRIORITY" and decremented in each loop. - * (see include/linux/mmzone.h) - */ +static int calc_inactive_ratio(struct mem_cgroup *memcg, unsigned long *present_pages) +{ + unsigned long active; + unsigned long inactive; + unsigned long gb; + unsigned long inactive_ratio; + + inactive = mem_cgroup_get_local_zonestat(memcg, LRU_INACTIVE_ANON); + active = mem_cgroup_get_local_zonestat(memcg, LRU_ACTIVE_ANON); -long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, struct zone *zone, - int priority, enum lru_list lru) + gb = (inactive + active) >> (30 - PAGE_SHIFT); + if (gb) + inactive_ratio = int_sqrt(10 * gb); + else + inactive_ratio = 1; + + if (present_pages) { + present_pages[0] = inactive; + present_pages[1] = active; + } + + return inactive_ratio; +} + +int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg) +{ + unsigned long active; + unsigned long inactive; + unsigned long present_pages[2]; + unsigned long inactive_ratio; + + inactive_ratio = calc_inactive_ratio(memcg, present_pages); + + inactive = present_pages[0]; + active = present_pages[1]; + + if (inactive * inactive_ratio < active) + return 1; + + return 0; +} + +int mem_cgroup_inactive_file_is_low(struct mem_cgroup *memcg) +{ + unsigned long active; + unsigned long inactive; + + inactive = mem_cgroup_get_local_zonestat(memcg, LRU_INACTIVE_FILE); + active = mem_cgroup_get_local_zonestat(memcg, LRU_ACTIVE_FILE); + + return (active > inactive); +} + +unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup *memcg, + struct zone *zone, + enum lru_list lru) +{ + int nid = zone->zone_pgdat->node_id; + int zid = zone_idx(zone); + struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); + + return MEM_CGROUP_ZSTAT(mz, lru); +} + +struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg, + struct zone *zone) { - long nr_pages; int nid = zone->zone_pgdat->node_id; int zid = zone_idx(zone); - struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(mem, nid, zid); + struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); + + return &mz->reclaim_stat; +} + +struct zone_reclaim_stat * +mem_cgroup_get_reclaim_stat_from_page(struct page *page) +{ + struct page_cgroup *pc; + struct mem_cgroup_per_zone *mz; - nr_pages = MEM_CGROUP_ZSTAT(mz, lru); + if (mem_cgroup_disabled()) + return NULL; + + pc = lookup_page_cgroup(page); + /* + * Used bit is set without atomic ops but after smp_wmb(). + * For making pc->mem_cgroup visible, insert smp_rmb() here. + */ + smp_rmb(); + if (!PageCgroupUsed(pc)) + return NULL; + + mz = page_cgroup_zoneinfo(pc); + if (!mz) + return NULL; - return (nr_pages >> priority); + return &mz->reclaim_stat; } unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, @@ -445,6 +649,7 @@ unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, int zid = zone_idx(z); struct mem_cgroup_per_zone *mz; int lru = LRU_FILE * !!file + !!active; + int ret; BUG_ON(!mem_cont); mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); @@ -462,9 +667,19 @@ unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, continue; scan++; - if (__isolate_lru_page(page, mode, file) == 0) { + ret = __isolate_lru_page(page, mode, file); + switch (ret) { + case 0: list_move(&page->lru, dst); + mem_cgroup_del_lru(page); nr_taken++; + break; + case -EBUSY: + /* we don't affect global LRU but rotate in our LRU */ + mem_cgroup_rotate_lru_list(page, page_lru(page)); + break; + default: + break; } } @@ -475,59 +690,117 @@ unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, #define mem_cgroup_from_res_counter(counter, member) \ container_of(counter, struct mem_cgroup, member) -/* - * This routine finds the DFS walk successor. This routine should be - * called with cgroup_mutex held +static bool mem_cgroup_check_under_limit(struct mem_cgroup *mem) +{ + if (do_swap_account) { + if (res_counter_check_under_limit(&mem->res) && + res_counter_check_under_limit(&mem->memsw)) + return true; + } else + if (res_counter_check_under_limit(&mem->res)) + return true; + return false; +} + +static unsigned int get_swappiness(struct mem_cgroup *memcg) +{ + struct cgroup *cgrp = memcg->css.cgroup; + unsigned int swappiness; + + /* root ? */ + if (cgrp->parent == NULL) + return vm_swappiness; + + spin_lock(&memcg->reclaim_param_lock); + swappiness = memcg->swappiness; + spin_unlock(&memcg->reclaim_param_lock); + + return swappiness; +} + +static int mem_cgroup_count_children_cb(struct mem_cgroup *mem, void *data) +{ + int *val = data; + (*val)++; + return 0; +} + +/** + * mem_cgroup_print_mem_info: Called from OOM with tasklist_lock held in read mode. + * @memcg: The memory cgroup that went over limit + * @p: Task that is going to be killed + * + * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is + * enabled */ -static struct mem_cgroup * -mem_cgroup_get_next_node(struct mem_cgroup *curr, struct mem_cgroup *root_mem) +void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) { - struct cgroup *cgroup, *curr_cgroup, *root_cgroup; + struct cgroup *task_cgrp; + struct cgroup *mem_cgrp; + /* + * Need a buffer in BSS, can't rely on allocations. The code relies + * on the assumption that OOM is serialized for memory controller. + * If this assumption is broken, revisit this code. + */ + static char memcg_name[PATH_MAX]; + int ret; + + if (!memcg) + return; + + + rcu_read_lock(); - curr_cgroup = curr->css.cgroup; - root_cgroup = root_mem->css.cgroup; + mem_cgrp = memcg->css.cgroup; + task_cgrp = task_cgroup(p, mem_cgroup_subsys_id); - if (!list_empty(&curr_cgroup->children)) { + ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX); + if (ret < 0) { /* - * Walk down to children + * Unfortunately, we are unable to convert to a useful name + * But we'll still print out the usage information */ - mem_cgroup_put(curr); - cgroup = list_entry(curr_cgroup->children.next, - struct cgroup, sibling); - curr = mem_cgroup_from_cont(cgroup); - mem_cgroup_get(curr); + rcu_read_unlock(); goto done; } + rcu_read_unlock(); -visit_parent: - if (curr_cgroup == root_cgroup) { - mem_cgroup_put(curr); - curr = root_mem; - mem_cgroup_get(curr); - goto done; - } + printk(KERN_INFO "Task in %s killed", memcg_name); - /* - * Goto next sibling - */ - if (curr_cgroup->sibling.next != &curr_cgroup->parent->children) { - mem_cgroup_put(curr); - cgroup = list_entry(curr_cgroup->sibling.next, struct cgroup, - sibling); - curr = mem_cgroup_from_cont(cgroup); - mem_cgroup_get(curr); + rcu_read_lock(); + ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX); + if (ret < 0) { + rcu_read_unlock(); goto done; } + rcu_read_unlock(); /* - * Go up to next parent and next parent's sibling if need be + * Continues from above, so we don't need an KERN_ level */ - curr_cgroup = curr_cgroup->parent; - goto visit_parent; - + printk(KERN_CONT " as a result of limit of %s\n", memcg_name); done: - root_mem->last_scanned_child = curr; - return curr; + + printk(KERN_INFO "memory: usage %llukB, limit %llukB, failcnt %llu\n", + res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, + res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, + res_counter_read_u64(&memcg->res, RES_FAILCNT)); + printk(KERN_INFO "memory+swap: usage %llukB, limit %llukB, " + "failcnt %llu\n", + res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, + res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, + res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); +} + +/* + * This function returns the number of memcg under hierarchy tree. Returns + * 1(self count) if no children. + */ +static int mem_cgroup_count_children(struct mem_cgroup *mem) +{ + int num = 0; + mem_cgroup_walk_tree(mem, &num, mem_cgroup_count_children_cb); + return num; } /* @@ -536,83 +809,154 @@ done: * that to reclaim free pages from. */ static struct mem_cgroup * -mem_cgroup_get_first_node(struct mem_cgroup *root_mem) +mem_cgroup_select_victim(struct mem_cgroup *root_mem) { - struct cgroup *cgroup; - struct mem_cgroup *ret; - bool obsolete = (root_mem->last_scanned_child && - root_mem->last_scanned_child->obsolete); + struct mem_cgroup *ret = NULL; + struct cgroup_subsys_state *css; + int nextid, found; - /* - * Scan all children under the mem_cgroup mem - */ - cgroup_lock(); - if (list_empty(&root_mem->css.cgroup->children)) { + if (!root_mem->use_hierarchy) { + css_get(&root_mem->css); ret = root_mem; - goto done; } - if (!root_mem->last_scanned_child || obsolete) { - - if (obsolete) - mem_cgroup_put(root_mem->last_scanned_child); + while (!ret) { + rcu_read_lock(); + nextid = root_mem->last_scanned_child + 1; + css = css_get_next(&mem_cgroup_subsys, nextid, &root_mem->css, + &found); + if (css && css_tryget(css)) + ret = container_of(css, struct mem_cgroup, css); - cgroup = list_first_entry(&root_mem->css.cgroup->children, - struct cgroup, sibling); - ret = mem_cgroup_from_cont(cgroup); - mem_cgroup_get(ret); - } else - ret = mem_cgroup_get_next_node(root_mem->last_scanned_child, - root_mem); + rcu_read_unlock(); + /* Updates scanning parameter */ + spin_lock(&root_mem->reclaim_param_lock); + if (!css) { + /* this means start scan from ID:1 */ + root_mem->last_scanned_child = 0; + } else + root_mem->last_scanned_child = found; + spin_unlock(&root_mem->reclaim_param_lock); + } -done: - root_mem->last_scanned_child = ret; - cgroup_unlock(); return ret; } /* - * Dance down the hierarchy if needed to reclaim memory. We remember the - * last child we reclaimed from, so that we don't end up penalizing - * one child extensively based on its position in the children list. + * Scan the hierarchy if needed to reclaim memory. We remember the last child + * we reclaimed from, so that we don't end up penalizing one child extensively + * based on its position in the children list. * * root_mem is the original ancestor that we've been reclaim from. + * + * We give up and return to the caller when we visit root_mem twice. + * (other groups can be removed while we're walking....) + * + * If shrink==true, for avoiding to free too much, this returns immedieately. */ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, - gfp_t gfp_mask, bool noswap) + gfp_t gfp_mask, bool noswap, bool shrink) +{ + struct mem_cgroup *victim; + int ret, total = 0; + int loop = 0; + + /* If memsw_is_minimum==1, swap-out is of-no-use. */ + if (root_mem->memsw_is_minimum) + noswap = true; + + while (loop < 2) { + victim = mem_cgroup_select_victim(root_mem); + if (victim == root_mem) + loop++; + if (!mem_cgroup_local_usage(&victim->stat)) { + /* this cgroup's local usage == 0 */ + css_put(&victim->css); + continue; + } + /* we use swappiness of local cgroup */ + ret = try_to_free_mem_cgroup_pages(victim, gfp_mask, noswap, + get_swappiness(victim)); + css_put(&victim->css); + /* + * At shrinking usage, we can't check we should stop here or + * reclaim more. It's depends on callers. last_scanned_child + * will work enough for keeping fairness under tree. + */ + if (shrink) + return ret; + total += ret; + if (mem_cgroup_check_under_limit(root_mem)) + return 1 + total; + } + return total; +} + +bool mem_cgroup_oom_called(struct task_struct *task) { - struct mem_cgroup *next_mem; - int ret = 0; + bool ret = false; + struct mem_cgroup *mem; + struct mm_struct *mm; + + rcu_read_lock(); + mm = task->mm; + if (!mm) + mm = &init_mm; + mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); + if (mem && time_before(jiffies, mem->last_oom_jiffies + HZ/10)) + ret = true; + rcu_read_unlock(); + return ret; +} + +static int record_last_oom_cb(struct mem_cgroup *mem, void *data) +{ + mem->last_oom_jiffies = jiffies; + return 0; +} + +static void record_last_oom(struct mem_cgroup *mem) +{ + mem_cgroup_walk_tree(mem, NULL, record_last_oom_cb); +} + +/* + * Currently used to update mapped file statistics, but the routine can be + * generalized to update other statistics as well. + */ +void mem_cgroup_update_mapped_file_stat(struct page *page, int val) +{ + struct mem_cgroup *mem; + struct mem_cgroup_stat *stat; + struct mem_cgroup_stat_cpu *cpustat; + int cpu; + struct page_cgroup *pc; + + if (!page_is_file_cache(page)) + return; + + pc = lookup_page_cgroup(page); + if (unlikely(!pc)) + return; + + lock_page_cgroup(pc); + mem = pc->mem_cgroup; + if (!mem) + goto done; + + if (!PageCgroupUsed(pc)) + goto done; /* - * Reclaim unconditionally and don't check for return value. - * We need to reclaim in the current group and down the tree. - * One might think about checking for children before reclaiming, - * but there might be left over accounting, even after children - * have left. + * Preemption is already disabled, we don't need get_cpu() */ - ret = try_to_free_mem_cgroup_pages(root_mem, gfp_mask, noswap); - if (res_counter_check_under_limit(&root_mem->res)) - return 0; - - next_mem = mem_cgroup_get_first_node(root_mem); + cpu = smp_processor_id(); + stat = &mem->stat; + cpustat = &stat->cpustat[cpu]; - while (next_mem != root_mem) { - if (next_mem->obsolete) { - mem_cgroup_put(next_mem); - cgroup_lock(); - next_mem = mem_cgroup_get_first_node(root_mem); - cgroup_unlock(); - continue; - } - ret = try_to_free_mem_cgroup_pages(next_mem, gfp_mask, noswap); - if (res_counter_check_under_limit(&root_mem->res)) - return 0; - cgroup_lock(); - next_mem = mem_cgroup_get_next_node(next_mem, root_mem); - cgroup_unlock(); - } - return ret; + __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_MAPPED_FILE, val); +done: + unlock_page_cgroup(pc); } /* @@ -626,29 +970,30 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm, struct mem_cgroup *mem, *mem_over_limit; int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; struct res_counter *fail_res; + + if (unlikely(test_thread_flag(TIF_MEMDIE))) { + /* Don't account this! */ + *memcg = NULL; + return 0; + } + /* * We always charge the cgroup the mm_struct belongs to. * The mm_struct's mem_cgroup changes on task migration if the * thread group leader migrates. It's possible that mm is not * set, if so charge the init_mm (happens for pagecache usage). - */ - if (likely(!*memcg)) { - rcu_read_lock(); - mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); - if (unlikely(!mem)) { - rcu_read_unlock(); - return 0; - } - /* - * For every charge from the cgroup, increment reference count - */ - css_get(&mem->css); + */ + mem = *memcg; + if (likely(!mem)) { + mem = try_get_mem_cgroup_from_mm(mm); *memcg = mem; - rcu_read_unlock(); } else { - mem = *memcg; css_get(&mem->css); } + if (unlikely(!mem)) + return 0; + + VM_BUG_ON(css_is_removed(&mem->css)); while (1) { int ret; @@ -676,7 +1021,9 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm, goto nomem; ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, gfp_mask, - noswap); + noswap, false); + if (ret) + continue; /* * try_to_free_mem_cgroup_pages() might not give us a full @@ -686,16 +1033,16 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm, * current usage of the cgroup before giving up * */ - if (!do_swap_account && - res_counter_check_under_limit(&mem->res)) - continue; - if (do_swap_account && - res_counter_check_under_limit(&mem->memsw)) + if (mem_cgroup_check_under_limit(mem_over_limit)) continue; if (!nr_retries--) { - if (oom) - mem_cgroup_out_of_memory(mem, gfp_mask); + if (oom) { + mutex_lock(&memcg_tasklist); + mem_cgroup_out_of_memory(mem_over_limit, gfp_mask); + mutex_unlock(&memcg_tasklist); + record_last_oom(mem_over_limit); + } goto nomem; } } @@ -705,27 +1052,59 @@ nomem: return -ENOMEM; } -/** - * mem_cgroup_try_charge - get charge of PAGE_SIZE. - * @mm: an mm_struct which is charged against. (when *memcg is NULL) - * @gfp_mask: gfp_mask for reclaim. - * @memcg: a pointer to memory cgroup which is charged against. - * - * charge against memory cgroup pointed by *memcg. if *memcg == NULL, estimated - * memory cgroup from @mm is got and stored in *memcg. - * - * Returns 0 if success. -ENOMEM at failure. - * This call can invoke OOM-Killer. + +/* + * A helper function to get mem_cgroup from ID. must be called under + * rcu_read_lock(). The caller must check css_is_removed() or some if + * it's concern. (dropping refcnt from swap can be called against removed + * memcg.) */ +static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) +{ + struct cgroup_subsys_state *css; + + /* ID 0 is unused ID */ + if (!id) + return NULL; + css = css_lookup(&mem_cgroup_subsys, id); + if (!css) + return NULL; + return container_of(css, struct mem_cgroup, css); +} -int mem_cgroup_try_charge(struct mm_struct *mm, - gfp_t mask, struct mem_cgroup **memcg) +static struct mem_cgroup *try_get_mem_cgroup_from_swapcache(struct page *page) { - return __mem_cgroup_try_charge(mm, mask, memcg, true); + struct mem_cgroup *mem; + struct page_cgroup *pc; + unsigned short id; + swp_entry_t ent; + + VM_BUG_ON(!PageLocked(page)); + + if (!PageSwapCache(page)) + return NULL; + + pc = lookup_page_cgroup(page); + lock_page_cgroup(pc); + if (PageCgroupUsed(pc)) { + mem = pc->mem_cgroup; + if (mem && !css_tryget(&mem->css)) + mem = NULL; + } else { + ent.val = page_private(page); + id = lookup_swap_cgroup(ent); + rcu_read_lock(); + mem = mem_cgroup_lookup(id); + if (mem && !css_tryget(&mem->css)) + mem = NULL; + rcu_read_unlock(); + } + unlock_page_cgroup(pc); + return mem; } /* - * commit a charge got by mem_cgroup_try_charge() and makes page_cgroup to be + * commit a charge got by __mem_cgroup_try_charge() and makes page_cgroup to be * USED state. If already USED, uncharge and return. */ @@ -777,6 +1156,10 @@ static int mem_cgroup_move_account(struct page_cgroup *pc, struct mem_cgroup_per_zone *from_mz, *to_mz; int nid, zid; int ret = -EBUSY; + struct page *page; + int cpu; + struct mem_cgroup_stat *stat; + struct mem_cgroup_stat_cpu *cpustat; VM_BUG_ON(from == to); VM_BUG_ON(PageLRU(pc->page)); @@ -795,17 +1178,41 @@ static int mem_cgroup_move_account(struct page_cgroup *pc, if (pc->mem_cgroup != from) goto out; - css_put(&from->css); res_counter_uncharge(&from->res, PAGE_SIZE); mem_cgroup_charge_statistics(from, pc, false); + + page = pc->page; + if (page_is_file_cache(page) && page_mapped(page)) { + cpu = smp_processor_id(); + /* Update mapped_file data for mem_cgroup "from" */ + stat = &from->stat; + cpustat = &stat->cpustat[cpu]; + __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_MAPPED_FILE, + -1); + + /* Update mapped_file data for mem_cgroup "to" */ + stat = &to->stat; + cpustat = &stat->cpustat[cpu]; + __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_MAPPED_FILE, + 1); + } + if (do_swap_account) res_counter_uncharge(&from->memsw, PAGE_SIZE); + css_put(&from->css); + + css_get(&to->css); pc->mem_cgroup = to; mem_cgroup_charge_statistics(to, pc, true); - css_get(&to->css); ret = 0; out: unlock_page_cgroup(pc); + /* + * We charges against "to" which may not have any tasks. Then, "to" + * can be under rmdir(). But in current implementation, caller of + * this function is just force_empty() and it's garanteed that + * "to" is never removed. So, we don't check rmdir status here. + */ return ret; } @@ -832,11 +1239,13 @@ static int mem_cgroup_move_parent(struct page_cgroup *pc, ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false); - if (ret) + if (ret || !parent) return ret; - if (!get_page_unless_zero(page)) - return -EBUSY; + if (!get_page_unless_zero(page)) { + ret = -EBUSY; + goto uncharge; + } ret = isolate_lru_page(page); @@ -845,19 +1254,23 @@ static int mem_cgroup_move_parent(struct page_cgroup *pc, ret = mem_cgroup_move_account(pc, child, parent); - /* drop extra refcnt by try_charge() (move_account increment one) */ - css_put(&parent->css); putback_lru_page(page); if (!ret) { put_page(page); + /* drop extra refcnt by try_charge() */ + css_put(&parent->css); return 0; } - /* uncharge if move fails */ + cancel: + put_page(page); +uncharge: + /* drop extra refcnt by try_charge() */ + css_put(&parent->css); + /* uncharge if move fails */ res_counter_uncharge(&parent->res, PAGE_SIZE); if (do_swap_account) res_counter_uncharge(&parent->memsw, PAGE_SIZE); - put_page(page); return ret; } @@ -883,7 +1296,7 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, mem = memcg; ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, true); - if (ret) + if (ret || !mem) return ret; __mem_cgroup_commit_charge(mem, pc, ctype); @@ -912,9 +1325,16 @@ int mem_cgroup_newpage_charge(struct page *page, MEM_CGROUP_CHARGE_TYPE_MAPPED, NULL); } +static void +__mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, + enum charge_type ctype); + int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) { + struct mem_cgroup *mem = NULL; + int ret; + if (mem_cgroup_disabled()) return 0; if (PageCompound(page)) @@ -927,6 +1347,8 @@ int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, * For GFP_NOWAIT case, the page may be pre-charged before calling * add_to_page_cache(). (See shmem.c) check it here and avoid to call * charge twice. (It works but has to pay a bit larger cost.) + * And when the page is SwapCache, it should take swap information + * into account. This is under lock_page() now. */ if (!(gfp_mask & __GFP_WAIT)) { struct page_cgroup *pc; @@ -943,30 +1365,44 @@ int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, unlock_page_cgroup(pc); } - if (unlikely(!mm)) + if (unlikely(!mm && !mem)) mm = &init_mm; if (page_is_file_cache(page)) return mem_cgroup_charge_common(page, mm, gfp_mask, MEM_CGROUP_CHARGE_TYPE_CACHE, NULL); - else - return mem_cgroup_charge_common(page, mm, gfp_mask, - MEM_CGROUP_CHARGE_TYPE_SHMEM, NULL); + + /* shmem */ + if (PageSwapCache(page)) { + ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); + if (!ret) + __mem_cgroup_commit_charge_swapin(page, mem, + MEM_CGROUP_CHARGE_TYPE_SHMEM); + } else + ret = mem_cgroup_charge_common(page, mm, gfp_mask, + MEM_CGROUP_CHARGE_TYPE_SHMEM, mem); + + return ret; } +/* + * While swap-in, try_charge -> commit or cancel, the page is locked. + * And when try_charge() successfully returns, one refcnt to memcg without + * struct page_cgroup is aquired. This refcnt will be cumsumed by + * "commit()" or removed by "cancel()" + */ int mem_cgroup_try_charge_swapin(struct mm_struct *mm, struct page *page, gfp_t mask, struct mem_cgroup **ptr) { struct mem_cgroup *mem; - swp_entry_t ent; + int ret; if (mem_cgroup_disabled()) return 0; if (!do_swap_account) goto charge_cur_mm; - /* * A racing thread's fault, or swapoff, may have already updated * the pte, and even removed page from swap cache: return success @@ -974,71 +1410,23 @@ int mem_cgroup_try_charge_swapin(struct mm_struct *mm, */ if (!PageSwapCache(page)) return 0; - - ent.val = page_private(page); - - mem = lookup_swap_cgroup(ent); - if (!mem || mem->obsolete) + mem = try_get_mem_cgroup_from_swapcache(page); + if (!mem) goto charge_cur_mm; *ptr = mem; - return __mem_cgroup_try_charge(NULL, mask, ptr, true); + ret = __mem_cgroup_try_charge(NULL, mask, ptr, true); + /* drop extra refcnt from tryget */ + css_put(&mem->css); + return ret; charge_cur_mm: if (unlikely(!mm)) mm = &init_mm; return __mem_cgroup_try_charge(mm, mask, ptr, true); } -#ifdef CONFIG_SWAP - -int mem_cgroup_cache_charge_swapin(struct page *page, - struct mm_struct *mm, gfp_t mask, bool locked) -{ - int ret = 0; - - if (mem_cgroup_disabled()) - return 0; - if (unlikely(!mm)) - mm = &init_mm; - if (!locked) - lock_page(page); - /* - * If not locked, the page can be dropped from SwapCache until - * we reach here. - */ - if (PageSwapCache(page)) { - struct mem_cgroup *mem = NULL; - swp_entry_t ent; - - ent.val = page_private(page); - if (do_swap_account) { - mem = lookup_swap_cgroup(ent); - if (mem && mem->obsolete) - mem = NULL; - if (mem) - mm = NULL; - } - ret = mem_cgroup_charge_common(page, mm, mask, - MEM_CGROUP_CHARGE_TYPE_SHMEM, mem); - - if (!ret && do_swap_account) { - /* avoid double counting */ - mem = swap_cgroup_record(ent, NULL); - if (mem) { - res_counter_uncharge(&mem->memsw, PAGE_SIZE); - mem_cgroup_put(mem); - } - } - } - if (!locked) - unlock_page(page); - /* add this page(page_cgroup) to the LRU we want. */ - mem_cgroup_lru_fixup(page); - - return ret; -} -#endif - -void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) +static void +__mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, + enum charge_type ctype) { struct page_cgroup *pc; @@ -1046,27 +1434,48 @@ void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) return; if (!ptr) return; + cgroup_exclude_rmdir(&ptr->css); pc = lookup_page_cgroup(page); - __mem_cgroup_commit_charge(ptr, pc, MEM_CGROUP_CHARGE_TYPE_MAPPED); + mem_cgroup_lru_del_before_commit_swapcache(page); + __mem_cgroup_commit_charge(ptr, pc, ctype); + mem_cgroup_lru_add_after_commit_swapcache(page); /* * Now swap is on-memory. This means this page may be * counted both as mem and swap....double count. - * Fix it by uncharging from memsw. This SwapCache is stable - * because we're still under lock_page(). + * Fix it by uncharging from memsw. Basically, this SwapCache is stable + * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page() + * may call delete_from_swap_cache() before reach here. */ - if (do_swap_account) { + if (do_swap_account && PageSwapCache(page)) { swp_entry_t ent = {.val = page_private(page)}; + unsigned short id; struct mem_cgroup *memcg; - memcg = swap_cgroup_record(ent, NULL); + + id = swap_cgroup_record(ent, 0); + rcu_read_lock(); + memcg = mem_cgroup_lookup(id); if (memcg) { - /* If memcg is obsolete, memcg can be != ptr */ + /* + * This recorded memcg can be obsolete one. So, avoid + * calling css_tryget + */ res_counter_uncharge(&memcg->memsw, PAGE_SIZE); mem_cgroup_put(memcg); } - + rcu_read_unlock(); } - /* add this page(page_cgroup) to the LRU we want. */ - mem_cgroup_lru_fixup(page); + /* + * At swapin, we may charge account against cgroup which has no tasks. + * So, rmdir()->pre_destroy() can be called while we do this charge. + * In that case, we need to call pre_destroy() again. check it here. + */ + cgroup_release_and_wakeup_rmdir(&ptr->css); +} + +void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) +{ + __mem_cgroup_commit_charge_swapin(page, ptr, + MEM_CGROUP_CHARGE_TYPE_MAPPED); } void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem) @@ -1114,6 +1523,7 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) switch (ctype) { case MEM_CGROUP_CHARGE_TYPE_MAPPED: + case MEM_CGROUP_CHARGE_TYPE_DROP: if (page_mapped(page)) goto unlock_out; break; @@ -1131,14 +1541,22 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) res_counter_uncharge(&mem->res, PAGE_SIZE); if (do_swap_account && (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT)) res_counter_uncharge(&mem->memsw, PAGE_SIZE); - mem_cgroup_charge_statistics(mem, pc, false); + ClearPageCgroupUsed(pc); + /* + * pc->mem_cgroup is not cleared here. It will be accessed when it's + * freed from LRU. This is safe because uncharged page is expected not + * to be reused (freed soon). Exception is SwapCache, it's handled by + * special functions. + */ mz = page_cgroup_zoneinfo(pc); unlock_page_cgroup(pc); - css_put(&mem->css); + /* at swapout, this memcg will be accessed to record to swap */ + if (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT) + css_put(&mem->css); return mem; @@ -1164,22 +1582,31 @@ void mem_cgroup_uncharge_cache_page(struct page *page) __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); } +#ifdef CONFIG_SWAP /* - * called from __delete_from_swap_cache() and drop "page" account. + * called after __delete_from_swap_cache() and drop "page" account. * memcg information is recorded to swap_cgroup of "ent" */ -void mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent) +void +mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout) { struct mem_cgroup *memcg; + int ctype = MEM_CGROUP_CHARGE_TYPE_SWAPOUT; + + if (!swapout) /* this was a swap cache but the swap is unused ! */ + ctype = MEM_CGROUP_CHARGE_TYPE_DROP; + + memcg = __mem_cgroup_uncharge_common(page, ctype); - memcg = __mem_cgroup_uncharge_common(page, - MEM_CGROUP_CHARGE_TYPE_SWAPOUT); /* record memcg information */ - if (do_swap_account && memcg) { - swap_cgroup_record(ent, memcg); + if (do_swap_account && swapout && memcg) { + swap_cgroup_record(ent, css_id(&memcg->css)); mem_cgroup_get(memcg); } + if (swapout && memcg) + css_put(&memcg->css); } +#endif #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP /* @@ -1189,15 +1616,23 @@ void mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent) void mem_cgroup_uncharge_swap(swp_entry_t ent) { struct mem_cgroup *memcg; + unsigned short id; if (!do_swap_account) return; - memcg = swap_cgroup_record(ent, NULL); + id = swap_cgroup_record(ent, 0); + rcu_read_lock(); + memcg = mem_cgroup_lookup(id); if (memcg) { + /* + * We uncharge this because swap is freed. + * This memcg can be obsolete one. We avoid calling css_tryget + */ res_counter_uncharge(&memcg->memsw, PAGE_SIZE); mem_cgroup_put(memcg); } + rcu_read_unlock(); } #endif @@ -1223,7 +1658,7 @@ int mem_cgroup_prepare_migration(struct page *page, struct mem_cgroup **ptr) unlock_page_cgroup(pc); if (mem) { - ret = mem_cgroup_try_charge(NULL, GFP_HIGHUSER_MOVABLE, &mem); + ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false); css_put(&mem->css); } *ptr = mem; @@ -1240,7 +1675,7 @@ void mem_cgroup_end_migration(struct mem_cgroup *mem, if (!mem) return; - + cgroup_exclude_rmdir(&mem->css); /* at migration success, oldpage->mapping is NULL. */ if (oldpage->mapping) { target = oldpage; @@ -1280,42 +1715,37 @@ void mem_cgroup_end_migration(struct mem_cgroup *mem, */ if (ctype == MEM_CGROUP_CHARGE_TYPE_MAPPED) mem_cgroup_uncharge_page(target); + /* + * At migration, we may charge account against cgroup which has no tasks + * So, rmdir()->pre_destroy() can be called while we do this charge. + * In that case, we need to call pre_destroy() again. check it here. + */ + cgroup_release_and_wakeup_rmdir(&mem->css); } /* - * A call to try to shrink memory usage under specified resource controller. - * This is typically used for page reclaiming for shmem for reducing side - * effect of page allocation from shmem, which is used by some mem_cgroup. + * A call to try to shrink memory usage on charge failure at shmem's swapin. + * Calling hierarchical_reclaim is not enough because we should update + * last_oom_jiffies to prevent pagefault_out_of_memory from invoking global OOM. + * Moreover considering hierarchy, we should reclaim from the mem_over_limit, + * not from the memcg which this page would be charged to. + * try_charge_swapin does all of these works properly. */ -int mem_cgroup_shrink_usage(struct mm_struct *mm, gfp_t gfp_mask) +int mem_cgroup_shmem_charge_fallback(struct page *page, + struct mm_struct *mm, + gfp_t gfp_mask) { - struct mem_cgroup *mem; - int progress = 0; - int retry = MEM_CGROUP_RECLAIM_RETRIES; + struct mem_cgroup *mem = NULL; + int ret; if (mem_cgroup_disabled()) return 0; - if (!mm) - return 0; - - rcu_read_lock(); - mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); - if (unlikely(!mem)) { - rcu_read_unlock(); - return 0; - } - css_get(&mem->css); - rcu_read_unlock(); - do { - progress = try_to_free_mem_cgroup_pages(mem, gfp_mask, true); - progress += res_counter_check_under_limit(&mem->res); - } while (!progress && --retry); + ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); + if (!ret) + mem_cgroup_cancel_charge_swapin(mem); /* it does !mem check */ - css_put(&mem->css); - if (!retry) - return -ENOMEM; - return 0; + return ret; } static DEFINE_MUTEX(set_limit_mutex); @@ -1323,11 +1753,21 @@ static DEFINE_MUTEX(set_limit_mutex); static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, unsigned long long val) { - - int retry_count = MEM_CGROUP_RECLAIM_RETRIES; + int retry_count; int progress; u64 memswlimit; int ret = 0; + int children = mem_cgroup_count_children(memcg); + u64 curusage, oldusage; + + /* + * For keeping hierarchical_reclaim simple, how long we should retry + * is depends on callers. We set our retry-count to be function + * of # of children which we should visit in this loop. + */ + retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; + + oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); while (retry_count) { if (signal_pending(current)) { @@ -1347,28 +1787,41 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, break; } ret = res_counter_set_limit(&memcg->res, val); + if (!ret) { + if (memswlimit == val) + memcg->memsw_is_minimum = true; + else + memcg->memsw_is_minimum = false; + } mutex_unlock(&set_limit_mutex); if (!ret) break; - progress = try_to_free_mem_cgroup_pages(memcg, - GFP_HIGHUSER_MOVABLE, false); - if (!progress) retry_count--; + progress = mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL, + false, true); + curusage = res_counter_read_u64(&memcg->res, RES_USAGE); + /* Usage is reduced ? */ + if (curusage >= oldusage) + retry_count--; + else + oldusage = curusage; } + return ret; } -int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, - unsigned long long val) +static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, + unsigned long long val) { - int retry_count = MEM_CGROUP_RECLAIM_RETRIES; + int retry_count; u64 memlimit, oldusage, curusage; - int ret; - - if (!do_swap_account) - return -EINVAL; + int children = mem_cgroup_count_children(memcg); + int ret = -EBUSY; + /* see mem_cgroup_resize_res_limit */ + retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; + oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); while (retry_count) { if (signal_pending(current)) { ret = -EINTR; @@ -1387,16 +1840,24 @@ int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, break; } ret = res_counter_set_limit(&memcg->memsw, val); + if (!ret) { + if (memlimit == val) + memcg->memsw_is_minimum = true; + else + memcg->memsw_is_minimum = false; + } mutex_unlock(&set_limit_mutex); if (!ret) break; - oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); - try_to_free_mem_cgroup_pages(memcg, GFP_HIGHUSER_MOVABLE, true); + mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL, true, true); curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); + /* Usage is reduced ? */ if (curusage >= oldusage) retry_count--; + else + oldusage = curusage; } return ret; } @@ -1439,7 +1900,7 @@ static int mem_cgroup_force_empty_list(struct mem_cgroup *mem, } spin_unlock_irqrestore(&zone->lru_lock, flags); - ret = mem_cgroup_move_parent(pc, mem, GFP_HIGHUSER_MOVABLE); + ret = mem_cgroup_move_parent(pc, mem, GFP_KERNEL); if (ret == -ENOMEM) break; @@ -1484,7 +1945,7 @@ move_account: /* This is for making all *used* pages to be on LRU. */ lru_add_drain_all(); ret = 0; - for_each_node_state(node, N_POSSIBLE) { + for_each_node_state(node, N_HIGH_MEMORY) { for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { enum lru_list l; for_each_lru(l) { @@ -1524,12 +1985,12 @@ try_to_free: ret = -EINTR; goto out; } - progress = try_to_free_mem_cgroup_pages(mem, - GFP_HIGHUSER_MOVABLE, false); + progress = try_to_free_mem_cgroup_pages(mem, GFP_KERNEL, + false, get_swappiness(mem)); if (!progress) { nr_retries--; /* maybe some writeback is necessary */ - congestion_wait(WRITE, HZ/10); + congestion_wait(BLK_RW_ASYNC, HZ/10); } } @@ -1598,8 +2059,7 @@ static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) val = res_counter_read_u64(&mem->res, name); break; case _MEMSWAP: - if (do_swap_account) - val = res_counter_read_u64(&mem->memsw, name); + val = res_counter_read_u64(&mem->memsw, name); break; default: BUG(); @@ -1639,6 +2099,34 @@ static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, return ret; } +static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, + unsigned long long *mem_limit, unsigned long long *memsw_limit) +{ + struct cgroup *cgroup; + unsigned long long min_limit, min_memsw_limit, tmp; + + min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); + min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); + cgroup = memcg->css.cgroup; + if (!memcg->use_hierarchy) + goto out; + + while (cgroup->parent) { + cgroup = cgroup->parent; + memcg = mem_cgroup_from_cont(cgroup); + if (!memcg->use_hierarchy) + break; + tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); + min_limit = min(min_limit, tmp); + tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); + min_memsw_limit = min(min_memsw_limit, tmp); + } +out: + *mem_limit = min_limit; + *memsw_limit = min_memsw_limit; + return; +} + static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) { struct mem_cgroup *mem; @@ -1664,54 +2152,176 @@ static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) return 0; } -static const struct mem_cgroup_stat_desc { - const char *msg; - u64 unit; -} mem_cgroup_stat_desc[] = { - [MEM_CGROUP_STAT_CACHE] = { "cache", PAGE_SIZE, }, - [MEM_CGROUP_STAT_RSS] = { "rss", PAGE_SIZE, }, - [MEM_CGROUP_STAT_PGPGIN_COUNT] = {"pgpgin", 1, }, - [MEM_CGROUP_STAT_PGPGOUT_COUNT] = {"pgpgout", 1, }, + +/* For read statistics */ +enum { + MCS_CACHE, + MCS_RSS, + MCS_MAPPED_FILE, + MCS_PGPGIN, + MCS_PGPGOUT, + MCS_INACTIVE_ANON, + MCS_ACTIVE_ANON, + MCS_INACTIVE_FILE, + MCS_ACTIVE_FILE, + MCS_UNEVICTABLE, + NR_MCS_STAT, }; +struct mcs_total_stat { + s64 stat[NR_MCS_STAT]; +}; + +struct { + char *local_name; + char *total_name; +} memcg_stat_strings[NR_MCS_STAT] = { + {"cache", "total_cache"}, + {"rss", "total_rss"}, + {"mapped_file", "total_mapped_file"}, + {"pgpgin", "total_pgpgin"}, + {"pgpgout", "total_pgpgout"}, + {"inactive_anon", "total_inactive_anon"}, + {"active_anon", "total_active_anon"}, + {"inactive_file", "total_inactive_file"}, + {"active_file", "total_active_file"}, + {"unevictable", "total_unevictable"} +}; + + +static int mem_cgroup_get_local_stat(struct mem_cgroup *mem, void *data) +{ + struct mcs_total_stat *s = data; + s64 val; + + /* per cpu stat */ + val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_CACHE); + s->stat[MCS_CACHE] += val * PAGE_SIZE; + val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_RSS); + s->stat[MCS_RSS] += val * PAGE_SIZE; + val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_MAPPED_FILE); + s->stat[MCS_MAPPED_FILE] += val * PAGE_SIZE; + val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_PGPGIN_COUNT); + s->stat[MCS_PGPGIN] += val; + val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_PGPGOUT_COUNT); + s->stat[MCS_PGPGOUT] += val; + + /* per zone stat */ + val = mem_cgroup_get_local_zonestat(mem, LRU_INACTIVE_ANON); + s->stat[MCS_INACTIVE_ANON] += val * PAGE_SIZE; + val = mem_cgroup_get_local_zonestat(mem, LRU_ACTIVE_ANON); + s->stat[MCS_ACTIVE_ANON] += val * PAGE_SIZE; + val = mem_cgroup_get_local_zonestat(mem, LRU_INACTIVE_FILE); + s->stat[MCS_INACTIVE_FILE] += val * PAGE_SIZE; + val = mem_cgroup_get_local_zonestat(mem, LRU_ACTIVE_FILE); + s->stat[MCS_ACTIVE_FILE] += val * PAGE_SIZE; + val = mem_cgroup_get_local_zonestat(mem, LRU_UNEVICTABLE); + s->stat[MCS_UNEVICTABLE] += val * PAGE_SIZE; + return 0; +} + +static void +mem_cgroup_get_total_stat(struct mem_cgroup *mem, struct mcs_total_stat *s) +{ + mem_cgroup_walk_tree(mem, s, mem_cgroup_get_local_stat); +} + static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, struct cgroup_map_cb *cb) { struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); - struct mem_cgroup_stat *stat = &mem_cont->stat; + struct mcs_total_stat mystat; int i; - for (i = 0; i < ARRAY_SIZE(stat->cpustat[0].count); i++) { - s64 val; + memset(&mystat, 0, sizeof(mystat)); + mem_cgroup_get_local_stat(mem_cont, &mystat); + + for (i = 0; i < NR_MCS_STAT; i++) + cb->fill(cb, memcg_stat_strings[i].local_name, mystat.stat[i]); - val = mem_cgroup_read_stat(stat, i); - val *= mem_cgroup_stat_desc[i].unit; - cb->fill(cb, mem_cgroup_stat_desc[i].msg, val); + /* Hierarchical information */ + { + unsigned long long limit, memsw_limit; + memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit); + cb->fill(cb, "hierarchical_memory_limit", limit); + if (do_swap_account) + cb->fill(cb, "hierarchical_memsw_limit", memsw_limit); } - /* showing # of active pages */ + + memset(&mystat, 0, sizeof(mystat)); + mem_cgroup_get_total_stat(mem_cont, &mystat); + for (i = 0; i < NR_MCS_STAT; i++) + cb->fill(cb, memcg_stat_strings[i].total_name, mystat.stat[i]); + + +#ifdef CONFIG_DEBUG_VM + cb->fill(cb, "inactive_ratio", calc_inactive_ratio(mem_cont, NULL)); + { - unsigned long active_anon, inactive_anon; - unsigned long active_file, inactive_file; - unsigned long unevictable; - - inactive_anon = mem_cgroup_get_all_zonestat(mem_cont, - LRU_INACTIVE_ANON); - active_anon = mem_cgroup_get_all_zonestat(mem_cont, - LRU_ACTIVE_ANON); - inactive_file = mem_cgroup_get_all_zonestat(mem_cont, - LRU_INACTIVE_FILE); - active_file = mem_cgroup_get_all_zonestat(mem_cont, - LRU_ACTIVE_FILE); - unevictable = mem_cgroup_get_all_zonestat(mem_cont, - LRU_UNEVICTABLE); - - cb->fill(cb, "active_anon", (active_anon) * PAGE_SIZE); - cb->fill(cb, "inactive_anon", (inactive_anon) * PAGE_SIZE); - cb->fill(cb, "active_file", (active_file) * PAGE_SIZE); - cb->fill(cb, "inactive_file", (inactive_file) * PAGE_SIZE); - cb->fill(cb, "unevictable", unevictable * PAGE_SIZE); + int nid, zid; + struct mem_cgroup_per_zone *mz; + unsigned long recent_rotated[2] = {0, 0}; + unsigned long recent_scanned[2] = {0, 0}; + + for_each_online_node(nid) + for (zid = 0; zid < MAX_NR_ZONES; zid++) { + mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); + + recent_rotated[0] += + mz->reclaim_stat.recent_rotated[0]; + recent_rotated[1] += + mz->reclaim_stat.recent_rotated[1]; + recent_scanned[0] += + mz->reclaim_stat.recent_scanned[0]; + recent_scanned[1] += + mz->reclaim_stat.recent_scanned[1]; + } + cb->fill(cb, "recent_rotated_anon", recent_rotated[0]); + cb->fill(cb, "recent_rotated_file", recent_rotated[1]); + cb->fill(cb, "recent_scanned_anon", recent_scanned[0]); + cb->fill(cb, "recent_scanned_file", recent_scanned[1]); + } +#endif + + return 0; +} +static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft) +{ + struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); + + return get_swappiness(memcg); +} + +static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, + u64 val) +{ + struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); + struct mem_cgroup *parent; + + if (val > 100) + return -EINVAL; + + if (cgrp->parent == NULL) + return -EINVAL; + + parent = mem_cgroup_from_cont(cgrp->parent); + + cgroup_lock(); + + /* If under hierarchy, only empty-root can set this value */ + if ((parent->use_hierarchy) || + (memcg->use_hierarchy && !list_empty(&cgrp->children))) { + cgroup_unlock(); + return -EINVAL; } + + spin_lock(&memcg->reclaim_param_lock); + memcg->swappiness = val; + spin_unlock(&memcg->reclaim_param_lock); + + cgroup_unlock(); + return 0; } @@ -1753,6 +2363,11 @@ static struct cftype mem_cgroup_files[] = { .write_u64 = mem_cgroup_hierarchy_write, .read_u64 = mem_cgroup_hierarchy_read, }, + { + .name = "swappiness", + .read_u64 = mem_cgroup_swappiness_read, + .write_u64 = mem_cgroup_swappiness_write, + }, }; #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP @@ -1861,19 +2476,14 @@ static struct mem_cgroup *mem_cgroup_alloc(void) * the number of reference from swap_cgroup and free mem_cgroup when * it goes down to 0. * - * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and - * entry which points to this memcg will be ignore at swapin. - * * Removal of cgroup itself succeeds regardless of refs from swap. */ -static void mem_cgroup_free(struct mem_cgroup *mem) +static void __mem_cgroup_free(struct mem_cgroup *mem) { int node; - if (atomic_read(&mem->refcnt) > 0) - return; - + free_css_id(&mem_cgroup_subsys, &mem->css); for_each_node_state(node, N_POSSIBLE) free_mem_cgroup_per_zone_info(mem, node); @@ -1892,12 +2502,22 @@ static void mem_cgroup_get(struct mem_cgroup *mem) static void mem_cgroup_put(struct mem_cgroup *mem) { if (atomic_dec_and_test(&mem->refcnt)) { - if (!mem->obsolete) - return; - mem_cgroup_free(mem); + struct mem_cgroup *parent = parent_mem_cgroup(mem); + __mem_cgroup_free(mem); + if (parent) + mem_cgroup_put(parent); } } +/* + * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. + */ +static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem) +{ + if (!mem->res.parent) + return NULL; + return mem_cgroup_from_res_counter(mem->res.parent, res); +} #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP static void __init enable_swap_cgroup(void) @@ -1911,15 +2531,16 @@ static void __init enable_swap_cgroup(void) } #endif -static struct cgroup_subsys_state * +static struct cgroup_subsys_state * __ref mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) { struct mem_cgroup *mem, *parent; + long error = -ENOMEM; int node; mem = mem_cgroup_alloc(); if (!mem) - return ERR_PTR(-ENOMEM); + return ERR_PTR(error); for_each_node_state(node, N_POSSIBLE) if (alloc_mem_cgroup_per_zone_info(mem, node)) @@ -1936,33 +2557,43 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) if (parent && parent->use_hierarchy) { res_counter_init(&mem->res, &parent->res); res_counter_init(&mem->memsw, &parent->memsw); + /* + * We increment refcnt of the parent to ensure that we can + * safely access it on res_counter_charge/uncharge. + * This refcnt will be decremented when freeing this + * mem_cgroup(see mem_cgroup_put). + */ + mem_cgroup_get(parent); } else { res_counter_init(&mem->res, NULL); res_counter_init(&mem->memsw, NULL); } + mem->last_scanned_child = 0; + spin_lock_init(&mem->reclaim_param_lock); - mem->last_scanned_child = NULL; - + if (parent) + mem->swappiness = get_swappiness(parent); + atomic_set(&mem->refcnt, 1); return &mem->css; free_out: - for_each_node_state(node, N_POSSIBLE) - free_mem_cgroup_per_zone_info(mem, node); - mem_cgroup_free(mem); - return ERR_PTR(-ENOMEM); + __mem_cgroup_free(mem); + return ERR_PTR(error); } -static void mem_cgroup_pre_destroy(struct cgroup_subsys *ss, +static int mem_cgroup_pre_destroy(struct cgroup_subsys *ss, struct cgroup *cont) { struct mem_cgroup *mem = mem_cgroup_from_cont(cont); - mem->obsolete = 1; - mem_cgroup_force_empty(mem, false); + + return mem_cgroup_force_empty(mem, false); } static void mem_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cont) { - mem_cgroup_free(mem_cgroup_from_cont(cont)); + struct mem_cgroup *mem = mem_cgroup_from_cont(cont); + + mem_cgroup_put(mem); } static int mem_cgroup_populate(struct cgroup_subsys *ss, @@ -1983,25 +2614,12 @@ static void mem_cgroup_move_task(struct cgroup_subsys *ss, struct cgroup *old_cont, struct task_struct *p) { - struct mm_struct *mm; - struct mem_cgroup *mem, *old_mem; - - mm = get_task_mm(p); - if (mm == NULL) - return; - - mem = mem_cgroup_from_cont(cont); - old_mem = mem_cgroup_from_cont(old_cont); - + mutex_lock(&memcg_tasklist); /* - * Only thread group leaders are allowed to migrate, the mm_struct is - * in effect owned by the leader + * FIXME: It's better to move charges of this process from old + * memcg to new memcg. But it's just on TODO-List now. */ - if (!thread_group_leader(p)) - goto out; - -out: - mmput(mm); + mutex_unlock(&memcg_tasklist); } struct cgroup_subsys mem_cgroup_subsys = { @@ -2013,6 +2631,7 @@ struct cgroup_subsys mem_cgroup_subsys = { .populate = mem_cgroup_populate, .attach = mem_cgroup_move_task, .early_init = 0, + .use_id = 1, }; #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP