diff options
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 1102 |
1 files changed, 500 insertions, 602 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index d87aa3510c5..602207be985 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -123,16 +123,22 @@ struct mem_cgroup_stat_cpu { unsigned long targets[MEM_CGROUP_NTARGETS]; }; +struct mem_cgroup_reclaim_iter { + /* css_id of the last scanned hierarchy member */ + int position; + /* scan generation, increased every round-trip */ + unsigned int generation; +}; + /* * per-zone information in memory controller. */ struct mem_cgroup_per_zone { - /* - * spin_lock to protect the per cgroup LRU - */ - struct list_head lists[NR_LRU_LISTS]; + struct lruvec lruvec; unsigned long count[NR_LRU_LISTS]; + struct mem_cgroup_reclaim_iter reclaim_iter[DEF_PRIORITY + 1]; + struct zone_reclaim_stat reclaim_stat; struct rb_node tree_node; /* RB tree node */ unsigned long long usage_in_excess;/* Set to the value by which */ @@ -233,11 +239,6 @@ struct mem_cgroup { * per zone LRU lists. */ struct mem_cgroup_lru_info info; - /* - * While reclaiming in a hierarchy, we cache the last child we - * reclaimed from. - */ - int last_scanned_child; int last_scanned_node; #if MAX_NUMNODES > 1 nodemask_t scan_nodes; @@ -366,8 +367,6 @@ enum charge_type { #define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT) #define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1 #define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT) -#define MEM_CGROUP_RECLAIM_SOFT_BIT 0x2 -#define MEM_CGROUP_RECLAIM_SOFT (1 << MEM_CGROUP_RECLAIM_SOFT_BIT) static void mem_cgroup_get(struct mem_cgroup *memcg); static void mem_cgroup_put(struct mem_cgroup *memcg); @@ -566,7 +565,7 @@ static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) struct mem_cgroup_per_zone *mz; struct mem_cgroup_tree_per_zone *mctz; - for_each_node_state(node, N_POSSIBLE) { + for_each_node(node) { for (zone = 0; zone < MAX_NR_ZONES; zone++) { mz = mem_cgroup_zoneinfo(memcg, node, zone); mctz = soft_limit_tree_node_zone(node, zone); @@ -656,16 +655,6 @@ static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg, this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_SWAPOUT], val); } -void mem_cgroup_pgfault(struct mem_cgroup *memcg, int val) -{ - this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT], val); -} - -void mem_cgroup_pgmajfault(struct mem_cgroup *memcg, int val) -{ - this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT], val); -} - static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg, enum mem_cgroup_events_index idx) { @@ -749,37 +738,32 @@ static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, return total; } -static bool __memcg_event_check(struct mem_cgroup *memcg, int target) +static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg, + enum mem_cgroup_events_target target) { unsigned long val, next; val = __this_cpu_read(memcg->stat->events[MEM_CGROUP_EVENTS_COUNT]); next = __this_cpu_read(memcg->stat->targets[target]); /* from time_after() in jiffies.h */ - return ((long)next - (long)val < 0); -} - -static void __mem_cgroup_target_update(struct mem_cgroup *memcg, int target) -{ - unsigned long val, next; - - val = __this_cpu_read(memcg->stat->events[MEM_CGROUP_EVENTS_COUNT]); - - switch (target) { - case MEM_CGROUP_TARGET_THRESH: - next = val + THRESHOLDS_EVENTS_TARGET; - break; - case MEM_CGROUP_TARGET_SOFTLIMIT: - next = val + SOFTLIMIT_EVENTS_TARGET; - break; - case MEM_CGROUP_TARGET_NUMAINFO: - next = val + NUMAINFO_EVENTS_TARGET; - break; - default: - return; + if ((long)next - (long)val < 0) { + switch (target) { + case MEM_CGROUP_TARGET_THRESH: + next = val + THRESHOLDS_EVENTS_TARGET; + break; + case MEM_CGROUP_TARGET_SOFTLIMIT: + next = val + SOFTLIMIT_EVENTS_TARGET; + break; + case MEM_CGROUP_TARGET_NUMAINFO: + next = val + NUMAINFO_EVENTS_TARGET; + break; + default: + break; + } + __this_cpu_write(memcg->stat->targets[target], next); + return true; } - - __this_cpu_write(memcg->stat->targets[target], next); + return false; } /* @@ -790,25 +774,27 @@ static void memcg_check_events(struct mem_cgroup *memcg, struct page *page) { preempt_disable(); /* threshold event is triggered in finer grain than soft limit */ - if (unlikely(__memcg_event_check(memcg, MEM_CGROUP_TARGET_THRESH))) { + if (unlikely(mem_cgroup_event_ratelimit(memcg, + MEM_CGROUP_TARGET_THRESH))) { + bool do_softlimit, do_numainfo; + + do_softlimit = mem_cgroup_event_ratelimit(memcg, + MEM_CGROUP_TARGET_SOFTLIMIT); +#if MAX_NUMNODES > 1 + do_numainfo = mem_cgroup_event_ratelimit(memcg, + MEM_CGROUP_TARGET_NUMAINFO); +#endif + preempt_enable(); + mem_cgroup_threshold(memcg); - __mem_cgroup_target_update(memcg, MEM_CGROUP_TARGET_THRESH); - if (unlikely(__memcg_event_check(memcg, - MEM_CGROUP_TARGET_SOFTLIMIT))) { + if (unlikely(do_softlimit)) mem_cgroup_update_tree(memcg, page); - __mem_cgroup_target_update(memcg, - MEM_CGROUP_TARGET_SOFTLIMIT); - } #if MAX_NUMNODES > 1 - if (unlikely(__memcg_event_check(memcg, - MEM_CGROUP_TARGET_NUMAINFO))) { + if (unlikely(do_numainfo)) atomic_inc(&memcg->numainfo_events); - __mem_cgroup_target_update(memcg, - MEM_CGROUP_TARGET_NUMAINFO); - } #endif - } - preempt_enable(); + } else + preempt_enable(); } struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) @@ -853,83 +839,116 @@ struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) return memcg; } -/* The caller has to guarantee "mem" exists before calling this */ -static struct mem_cgroup *mem_cgroup_start_loop(struct mem_cgroup *memcg) +/** + * mem_cgroup_iter - iterate over memory cgroup hierarchy + * @root: hierarchy root + * @prev: previously returned memcg, NULL on first invocation + * @reclaim: cookie for shared reclaim walks, NULL for full walks + * + * Returns references to children of the hierarchy below @root, or + * @root itself, or %NULL after a full round-trip. + * + * Caller must pass the return value in @prev on subsequent + * invocations for reference counting, or use mem_cgroup_iter_break() + * to cancel a hierarchy walk before the round-trip is complete. + * + * Reclaimers can specify a zone and a priority level in @reclaim to + * divide up the memcgs in the hierarchy among all concurrent + * reclaimers operating on the same zone and priority. + */ +struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, + struct mem_cgroup *prev, + struct mem_cgroup_reclaim_cookie *reclaim) { - struct cgroup_subsys_state *css; - int found; + struct mem_cgroup *memcg = NULL; + int id = 0; - if (!memcg) /* ROOT cgroup has the smallest ID */ - return root_mem_cgroup; /*css_put/get against root is ignored*/ - if (!memcg->use_hierarchy) { - if (css_tryget(&memcg->css)) - return memcg; + if (mem_cgroup_disabled()) return NULL; - } - rcu_read_lock(); - /* - * searching a memory cgroup which has the smallest ID under given - * ROOT cgroup. (ID >= 1) - */ - css = css_get_next(&mem_cgroup_subsys, 1, &memcg->css, &found); - if (css && css_tryget(css)) - memcg = container_of(css, struct mem_cgroup, css); - else - memcg = NULL; - rcu_read_unlock(); - return memcg; -} -static struct mem_cgroup *mem_cgroup_get_next(struct mem_cgroup *iter, - struct mem_cgroup *root, - bool cond) -{ - int nextid = css_id(&iter->css) + 1; - int found; - int hierarchy_used; - struct cgroup_subsys_state *css; + if (!root) + root = root_mem_cgroup; - hierarchy_used = iter->use_hierarchy; + if (prev && !reclaim) + id = css_id(&prev->css); - css_put(&iter->css); - /* If no ROOT, walk all, ignore hierarchy */ - if (!cond || (root && !hierarchy_used)) - return NULL; + if (prev && prev != root) + css_put(&prev->css); - if (!root) - root = root_mem_cgroup; + if (!root->use_hierarchy && root != root_mem_cgroup) { + if (prev) + return NULL; + return root; + } - do { - iter = NULL; - rcu_read_lock(); + while (!memcg) { + struct mem_cgroup_reclaim_iter *uninitialized_var(iter); + struct cgroup_subsys_state *css; + + if (reclaim) { + int nid = zone_to_nid(reclaim->zone); + int zid = zone_idx(reclaim->zone); + struct mem_cgroup_per_zone *mz; - css = css_get_next(&mem_cgroup_subsys, nextid, - &root->css, &found); - if (css && css_tryget(css)) - iter = container_of(css, struct mem_cgroup, css); + mz = mem_cgroup_zoneinfo(root, nid, zid); + iter = &mz->reclaim_iter[reclaim->priority]; + if (prev && reclaim->generation != iter->generation) + return NULL; + id = iter->position; + } + + rcu_read_lock(); + css = css_get_next(&mem_cgroup_subsys, id + 1, &root->css, &id); + if (css) { + if (css == &root->css || css_tryget(css)) + memcg = container_of(css, + struct mem_cgroup, css); + } else + id = 0; rcu_read_unlock(); - /* If css is NULL, no more cgroups will be found */ - nextid = found + 1; - } while (css && !iter); - return iter; + if (reclaim) { + iter->position = id; + if (!css) + iter->generation++; + else if (!prev && memcg) + reclaim->generation = iter->generation; + } + + if (prev && !css) + return NULL; + } + return memcg; } -/* - * for_eacn_mem_cgroup_tree() for visiting all cgroup under tree. Please - * be careful that "break" loop is not allowed. We have reference count. - * Instead of that modify "cond" to be false and "continue" to exit the loop. - */ -#define for_each_mem_cgroup_tree_cond(iter, root, cond) \ - for (iter = mem_cgroup_start_loop(root);\ - iter != NULL;\ - iter = mem_cgroup_get_next(iter, root, cond)) -#define for_each_mem_cgroup_tree(iter, root) \ - for_each_mem_cgroup_tree_cond(iter, root, true) +/** + * mem_cgroup_iter_break - abort a hierarchy walk prematurely + * @root: hierarchy root + * @prev: last visited hierarchy member as returned by mem_cgroup_iter() + */ +void mem_cgroup_iter_break(struct mem_cgroup *root, + struct mem_cgroup *prev) +{ + if (!root) + root = root_mem_cgroup; + if (prev && prev != root) + css_put(&prev->css); +} -#define for_each_mem_cgroup_all(iter) \ - for_each_mem_cgroup_tree_cond(iter, NULL, true) +/* + * Iteration constructs for visiting all cgroups (under a tree). If + * loops are exited prematurely (break), mem_cgroup_iter_break() must + * be used for reference counting. + */ +#define for_each_mem_cgroup_tree(iter, root) \ + for (iter = mem_cgroup_iter(root, NULL, NULL); \ + iter != NULL; \ + iter = mem_cgroup_iter(root, iter, NULL)) +#define for_each_mem_cgroup(iter) \ + for (iter = mem_cgroup_iter(NULL, NULL, NULL); \ + iter != NULL; \ + iter = mem_cgroup_iter(NULL, iter, NULL)) static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) { @@ -949,11 +968,11 @@ void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) goto out; switch (idx) { - case PGMAJFAULT: - mem_cgroup_pgmajfault(memcg, 1); - break; case PGFAULT: - mem_cgroup_pgfault(memcg, 1); + this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT]); + break; + case PGMAJFAULT: + this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT]); break; default: BUG(); @@ -963,6 +982,27 @@ out: } EXPORT_SYMBOL(mem_cgroup_count_vm_event); +/** + * mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg + * @zone: zone of the wanted lruvec + * @mem: memcg of the wanted lruvec + * + * Returns the lru list vector holding pages for the given @zone and + * @mem. This can be the global zone lruvec, if the memory controller + * is disabled. + */ +struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone, + struct mem_cgroup *memcg) +{ + struct mem_cgroup_per_zone *mz; + + if (mem_cgroup_disabled()) + return &zone->lruvec; + + mz = mem_cgroup_zoneinfo(memcg, zone_to_nid(zone), zone_idx(zone)); + return &mz->lruvec; +} + /* * Following LRU functions are allowed to be used without PCG_LOCK. * Operations are called by routine of global LRU independently from memcg. @@ -977,180 +1017,91 @@ EXPORT_SYMBOL(mem_cgroup_count_vm_event); * When moving account, the page is not on LRU. It's isolated. */ -void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru) -{ - struct page_cgroup *pc; - struct mem_cgroup_per_zone *mz; - - if (mem_cgroup_disabled()) - return; - pc = lookup_page_cgroup(page); - /* can happen while we handle swapcache. */ - if (!TestClearPageCgroupAcctLRU(pc)) - return; - VM_BUG_ON(!pc->mem_cgroup); - /* - * 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_cgroup, page); - /* huge page split is done under lru_lock. so, we have no races. */ - MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page); - if (mem_cgroup_is_root(pc->mem_cgroup)) - return; - VM_BUG_ON(list_empty(&pc->lru)); - list_del_init(&pc->lru); -} - -void mem_cgroup_del_lru(struct page *page) -{ - mem_cgroup_del_lru_list(page, page_lru(page)); -} - -/* - * Writeback is about to end against a page which has been marked for immediate - * reclaim. If it still appears to be reclaimable, move it to the tail of the - * inactive list. +/** + * mem_cgroup_lru_add_list - account for adding an lru page and return lruvec + * @zone: zone of the page + * @page: the page + * @lru: current lru + * + * This function accounts for @page being added to @lru, and returns + * the lruvec for the given @zone and the memcg @page is charged to. + * + * The callsite is then responsible for physically linking the page to + * the returned lruvec->lists[@lru]. */ -void mem_cgroup_rotate_reclaimable_page(struct page *page) +struct lruvec *mem_cgroup_lru_add_list(struct zone *zone, struct page *page, + enum lru_list lru) { struct mem_cgroup_per_zone *mz; + struct mem_cgroup *memcg; struct page_cgroup *pc; - enum lru_list lru = page_lru(page); if (mem_cgroup_disabled()) - return; + return &zone->lruvec; pc = lookup_page_cgroup(page); - /* unused or root page is not rotated. */ - if (!PageCgroupUsed(pc)) - return; - /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ - smp_rmb(); - if (mem_cgroup_is_root(pc->mem_cgroup)) - return; - mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); - list_move_tail(&pc->lru, &mz->lists[lru]); + memcg = pc->mem_cgroup; + mz = page_cgroup_zoneinfo(memcg, page); + /* compound_order() is stabilized through lru_lock */ + MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page); + return &mz->lruvec; } -void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru) +/** + * mem_cgroup_lru_del_list - account for removing an lru page + * @page: the page + * @lru: target lru + * + * This function accounts for @page being removed from @lru. + * + * The callsite is then responsible for physically unlinking + * @page->lru. + */ +void mem_cgroup_lru_del_list(struct page *page, enum lru_list lru) { struct mem_cgroup_per_zone *mz; + struct mem_cgroup *memcg; struct page_cgroup *pc; if (mem_cgroup_disabled()) return; pc = lookup_page_cgroup(page); - /* unused or root page is not rotated. */ - if (!PageCgroupUsed(pc)) - return; - /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ - smp_rmb(); - if (mem_cgroup_is_root(pc->mem_cgroup)) - return; - mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); - list_move(&pc->lru, &mz->lists[lru]); -} - -void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru) -{ - struct page_cgroup *pc; - struct mem_cgroup_per_zone *mz; - - if (mem_cgroup_disabled()) - return; - pc = lookup_page_cgroup(page); - VM_BUG_ON(PageCgroupAcctLRU(pc)); - /* - * putback: charge: - * SetPageLRU SetPageCgroupUsed - * smp_mb smp_mb - * PageCgroupUsed && add to memcg LRU PageLRU && add to memcg LRU - * - * Ensure that one of the two sides adds the page to the memcg - * LRU during a race. - */ - smp_mb(); - if (!PageCgroupUsed(pc)) - return; - /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ - smp_rmb(); - mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); + memcg = pc->mem_cgroup; + VM_BUG_ON(!memcg); + mz = page_cgroup_zoneinfo(memcg, page); /* huge page split is done under lru_lock. so, we have no races. */ - MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page); - SetPageCgroupAcctLRU(pc); - if (mem_cgroup_is_root(pc->mem_cgroup)) - return; - list_add(&pc->lru, &mz->lists[lru]); -} - -/* - * At handling SwapCache and other FUSE stuff, pc->mem_cgroup may be changed - * while it's linked to lru because the page may be reused after it's fully - * uncharged. To handle that, unlink page_cgroup from LRU when charge it again. - * It's done under lock_page and expected that zone->lru_lock isnever held. - */ -static void mem_cgroup_lru_del_before_commit(struct page *page) -{ - unsigned long flags; - struct zone *zone = page_zone(page); - struct page_cgroup *pc = lookup_page_cgroup(page); - - /* - * Doing this check without taking ->lru_lock seems wrong but this - * is safe. Because if page_cgroup's USED bit is unset, the page - * will not be added to any memcg's LRU. If page_cgroup's USED bit is - * set, the commit after this will fail, anyway. - * This all charge/uncharge is done under some mutual execustion. - * So, we don't need to taking care of changes in USED bit. - */ - if (likely(!PageLRU(page))) - return; - - 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); + VM_BUG_ON(MEM_CGROUP_ZSTAT(mz, lru) < (1 << compound_order(page))); + MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page); } -static void mem_cgroup_lru_add_after_commit(struct page *page) +void mem_cgroup_lru_del(struct page *page) { - unsigned long flags; - struct zone *zone = page_zone(page); - struct page_cgroup *pc = lookup_page_cgroup(page); - /* - * putback: charge: - * SetPageLRU SetPageCgroupUsed - * smp_mb smp_mb - * PageCgroupUsed && add to memcg LRU PageLRU && add to memcg LRU - * - * Ensure that one of the two sides adds the page to the memcg - * LRU during a race. - */ - smp_mb(); - /* taking care of that the page is added to LRU while we commit it */ - if (likely(!PageLRU(page))) - return; - spin_lock_irqsave(&zone->lru_lock, flags); - /* link when the page is linked to LRU but page_cgroup isn't */ - if (PageLRU(page) && !PageCgroupAcctLRU(pc)) - mem_cgroup_add_lru_list(page, page_lru(page)); - spin_unlock_irqrestore(&zone->lru_lock, flags); + mem_cgroup_lru_del_list(page, page_lru(page)); } - -void mem_cgroup_move_lists(struct page *page, - enum lru_list from, enum lru_list to) +/** + * mem_cgroup_lru_move_lists - account for moving a page between lrus + * @zone: zone of the page + * @page: the page + * @from: current lru + * @to: target lru + * + * This function accounts for @page being moved between the lrus @from + * and @to, and returns the lruvec for the given @zone and the memcg + * @page is charged to. + * + * The callsite is then responsible for physically relinking + * @page->lru to the returned lruvec->lists[@to]. + */ +struct lruvec *mem_cgroup_lru_move_lists(struct zone *zone, + struct page *page, + enum lru_list from, + enum lru_list to) { - if (mem_cgroup_disabled()) - return; - mem_cgroup_del_lru_list(page, from); - mem_cgroup_add_lru_list(page, to); + /* XXX: Optimize this, especially for @from == @to */ + mem_cgroup_lru_del_list(page, from); + return mem_cgroup_lru_add_list(zone, page, to); } /* @@ -1175,10 +1126,21 @@ int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *memcg) struct task_struct *p; p = find_lock_task_mm(task); - if (!p) - return 0; - curr = try_get_mem_cgroup_from_mm(p->mm); - task_unlock(p); + if (p) { + curr = try_get_mem_cgroup_from_mm(p->mm); + task_unlock(p); + } else { + /* + * All threads may have already detached their mm's, but the oom + * killer still needs to detect if they have already been oom + * killed to prevent needlessly killing additional tasks. + */ + task_lock(task); + curr = mem_cgroup_from_task(task); + if (curr) + css_get(&curr->css); + task_unlock(task); + } if (!curr) return 0; /* @@ -1258,68 +1220,6 @@ mem_cgroup_get_reclaim_stat_from_page(struct page *page) return &mz->reclaim_stat; } -unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, - struct list_head *dst, - unsigned long *scanned, int order, - isolate_mode_t mode, - struct zone *z, - struct mem_cgroup *mem_cont, - int active, int file) -{ - unsigned long nr_taken = 0; - struct page *page; - unsigned long scan; - LIST_HEAD(pc_list); - struct list_head *src; - struct page_cgroup *pc, *tmp; - int nid = zone_to_nid(z); - 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); - src = &mz->lists[lru]; - - scan = 0; - list_for_each_entry_safe_reverse(pc, tmp, src, lru) { - if (scan >= nr_to_scan) - break; - - if (unlikely(!PageCgroupUsed(pc))) - continue; - - page = lookup_cgroup_page(pc); - - if (unlikely(!PageLRU(page))) - continue; - - scan++; - ret = __isolate_lru_page(page, mode, file); - switch (ret) { - case 0: - list_move(&page->lru, dst); - mem_cgroup_del_lru(page); - nr_taken += hpage_nr_pages(page); - 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; - } - } - - *scanned = scan; - - trace_mm_vmscan_memcg_isolate(0, nr_to_scan, scan, nr_taken, - 0, 0, 0, mode); - - return nr_taken; -} - #define mem_cgroup_from_res_counter(counter, member) \ container_of(counter, struct mem_cgroup, member) @@ -1536,41 +1436,40 @@ u64 mem_cgroup_get_limit(struct mem_cgroup *memcg) return min(limit, memsw); } -/* - * Visit the first child (need not be the first child as per the ordering - * of the cgroup list, since we track last_scanned_child) of @mem and use - * that to reclaim free pages from. - */ -static struct mem_cgroup * -mem_cgroup_select_victim(struct mem_cgroup *root_memcg) +static unsigned long mem_cgroup_reclaim(struct mem_cgroup *memcg, + gfp_t gfp_mask, + unsigned long flags) { - struct mem_cgroup *ret = NULL; - struct cgroup_subsys_state *css; - int nextid, found; - - if (!root_memcg->use_hierarchy) { - css_get(&root_memcg->css); - ret = root_memcg; - } + unsigned long total = 0; + bool noswap = false; + int loop; - while (!ret) { - rcu_read_lock(); - nextid = root_memcg->last_scanned_child + 1; - css = css_get_next(&mem_cgroup_subsys, nextid, &root_memcg->css, - &found); - if (css && css_tryget(css)) - ret = container_of(css, struct mem_cgroup, css); + if (flags & MEM_CGROUP_RECLAIM_NOSWAP) + noswap = true; + if (!(flags & MEM_CGROUP_RECLAIM_SHRINK) && memcg->memsw_is_minimum) + noswap = true; - rcu_read_unlock(); - /* Updates scanning parameter */ - if (!css) { - /* this means start scan from ID:1 */ - root_memcg->last_scanned_child = 0; - } else - root_memcg->last_scanned_child = found; + for (loop = 0; loop < MEM_CGROUP_MAX_RECLAIM_LOOPS; loop++) { + if (loop) + drain_all_stock_async(memcg); + total += try_to_free_mem_cgroup_pages(memcg, gfp_mask, noswap); + /* + * Allow limit shrinkers, which are triggered directly + * by userspace, to catch signals and stop reclaim + * after minimal progress, regardless of the margin. + */ + if (total && (flags & MEM_CGROUP_RECLAIM_SHRINK)) + break; + if (mem_cgroup_margin(memcg)) + break; + /* + * If nothing was reclaimed after two attempts, there + * may be no reclaimable pages in this hierarchy. + */ + if (loop && !total) + break; } - - return ret; + return total; } /** @@ -1710,61 +1609,35 @@ bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) } #endif -/* - * 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_memcg is the original ancestor that we've been reclaim from. - * - * We give up and return to the caller when we visit root_memcg 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_memcg, - struct zone *zone, - gfp_t gfp_mask, - unsigned long reclaim_options, - unsigned long *total_scanned) -{ - struct mem_cgroup *victim; - int ret, total = 0; +static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, + struct zone *zone, + gfp_t gfp_mask, + unsigned long *total_scanned) +{ + struct mem_cgroup *victim = NULL; + int total = 0; int loop = 0; - bool noswap = reclaim_options & MEM_CGROUP_RECLAIM_NOSWAP; - bool shrink = reclaim_options & MEM_CGROUP_RECLAIM_SHRINK; - bool check_soft = reclaim_options & MEM_CGROUP_RECLAIM_SOFT; unsigned long excess; unsigned long nr_scanned; + struct mem_cgroup_reclaim_cookie reclaim = { + .zone = zone, + .priority = 0, + }; excess = res_counter_soft_limit_excess(&root_memcg->res) >> PAGE_SHIFT; - /* If memsw_is_minimum==1, swap-out is of-no-use. */ - if (!check_soft && !shrink && root_memcg->memsw_is_minimum) - noswap = true; - while (1) { - victim = mem_cgroup_select_victim(root_memcg); - if (victim == root_memcg) { + victim = mem_cgroup_iter(root_memcg, victim, &reclaim); + if (!victim) { loop++; - /* - * We are not draining per cpu cached charges during - * soft limit reclaim because global reclaim doesn't - * care about charges. It tries to free some memory and - * charges will not give any. - */ - if (!check_soft && loop >= 1) - drain_all_stock_async(root_memcg); if (loop >= 2) { /* * If we have not been able to reclaim * anything, it might because there are * no reclaimable pages under this hierarchy */ - if (!check_soft || !total) { - css_put(&victim->css); + if (!total) break; - } /* * We want to do more targeted reclaim. * excess >> 2 is not to excessive so as to @@ -1772,40 +1645,20 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_memcg, * coming back to reclaim from this cgroup */ if (total >= (excess >> 2) || - (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) { - css_put(&victim->css); + (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) break; - } } - } - if (!mem_cgroup_reclaimable(victim, noswap)) { - /* this cgroup's local usage == 0 */ - css_put(&victim->css); continue; } - /* we use swappiness of local cgroup */ - if (check_soft) { - ret = mem_cgroup_shrink_node_zone(victim, gfp_mask, - noswap, zone, &nr_scanned); - *total_scanned += nr_scanned; - } else - ret = try_to_free_mem_cgroup_pages(victim, gfp_mask, - noswap); - 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 (check_soft) { - if (!res_counter_soft_limit_excess(&root_memcg->res)) - return total; - } else if (mem_cgroup_margin(root_memcg)) - return total; + if (!mem_cgroup_reclaimable(victim, false)) + continue; + total += mem_cgroup_shrink_node_zone(victim, gfp_mask, false, + zone, &nr_scanned); + *total_scanned += nr_scanned; + if (!res_counter_soft_limit_excess(&root_memcg->res)) + break; } + mem_cgroup_iter_break(root_memcg, victim); return total; } @@ -1817,16 +1670,16 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_memcg, static bool mem_cgroup_oom_lock(struct mem_cgroup *memcg) { struct mem_cgroup *iter, *failed = NULL; - bool cond = true; - for_each_mem_cgroup_tree_cond(iter, memcg, cond) { + for_each_mem_cgroup_tree(iter, memcg) { if (iter->oom_lock) { /* * this subtree of our hierarchy is already locked * so we cannot give a lock. */ failed = iter; - cond = false; + mem_cgroup_iter_break(memcg, iter); + break; } else iter->oom_lock = true; } @@ -1838,11 +1691,10 @@ static bool mem_cgroup_oom_lock(struct mem_cgroup *memcg) * OK, we failed to lock the whole subtree so we have to clean up * what we set up to the failing subtree */ - cond = true; - for_each_mem_cgroup_tree_cond(iter, memcg, cond) { + for_each_mem_cgroup_tree(iter, memcg) { if (iter == failed) { - cond = false; - continue; + mem_cgroup_iter_break(memcg, iter); + break; } iter->oom_lock = false; } @@ -2007,7 +1859,7 @@ void mem_cgroup_update_page_stat(struct page *page, bool need_unlock = false; unsigned long uninitialized_var(flags); - if (unlikely(!pc)) + if (mem_cgroup_disabled()) return; rcu_read_lock(); @@ -2238,7 +2090,7 @@ static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, struct mem_cgroup *iter; if ((action == CPU_ONLINE)) { - for_each_mem_cgroup_all(iter) + for_each_mem_cgroup(iter) synchronize_mem_cgroup_on_move(iter, cpu); return NOTIFY_OK; } @@ -2246,7 +2098,7 @@ static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN) return NOTIFY_OK; - for_each_mem_cgroup_all(iter) + for_each_mem_cgroup(iter) mem_cgroup_drain_pcp_counter(iter, cpu); stock = &per_cpu(memcg_stock, cpu); @@ -2300,8 +2152,7 @@ static int mem_cgroup_do_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, if (!(gfp_mask & __GFP_WAIT)) return CHARGE_WOULDBLOCK; - ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, NULL, - gfp_mask, flags, NULL); + ret = mem_cgroup_reclaim(mem_over_limit, gfp_mask, flags); if (mem_cgroup_margin(mem_over_limit) >= nr_pages) return CHARGE_RETRY; /* @@ -2334,8 +2185,25 @@ static int mem_cgroup_do_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, } /* - * Unlike exported interface, "oom" parameter is added. if oom==true, - * oom-killer can be invoked. + * __mem_cgroup_try_charge() does + * 1. detect memcg to be charged against from passed *mm and *ptr, + * 2. update res_counter + * 3. call memory reclaim if necessary. + * + * In some special case, if the task is fatal, fatal_signal_pending() or + * has TIF_MEMDIE, this function returns -EINTR while writing root_mem_cgroup + * to *ptr. There are two reasons for this. 1: fatal threads should quit as soon + * as possible without any hazards. 2: all pages should have a valid + * pc->mem_cgroup. If mm is NULL and the caller doesn't pass a valid memcg + * pointer, that is treated as a charge to root_mem_cgroup. + * + * So __mem_cgroup_try_charge() will return + * 0 ... on success, filling *ptr with a valid memcg pointer. + * -ENOMEM ... charge failure because of resource limits. + * -EINTR ... if thread is fatal. *ptr is filled with root_mem_cgroup. + * + * Unlike the exported interface, an "oom" parameter is added. if oom==true, + * the oom-killer can be invoked. */ static int __mem_cgroup_try_charge(struct mm_struct *mm, gfp_t gfp_mask, @@ -2364,7 +2232,7 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm, * set, if so charge the init_mm (happens for pagecache usage). */ if (!*ptr && !mm) - goto bypass; + *ptr = root_mem_cgroup; again: if (*ptr) { /* css should be a valid one */ memcg = *ptr; @@ -2390,7 +2258,9 @@ again: * task-struct. So, mm->owner can be NULL. */ memcg = mem_cgroup_from_task(p); - if (!memcg || mem_cgroup_is_root(memcg)) { + if (!memcg) + memcg = root_mem_cgroup; + if (mem_cgroup_is_root(memcg)) { rcu_read_unlock(); goto done; } @@ -2465,8 +2335,8 @@ nomem: *ptr = NULL; return -ENOMEM; bypass: - *ptr = NULL; - return 0; + *ptr = root_mem_cgroup; + return -EINTR; } /* @@ -2522,7 +2392,7 @@ struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) memcg = NULL; } else if (PageSwapCache(page)) { ent.val = page_private(page); - id = lookup_swap_cgroup(ent); + id = lookup_swap_cgroup_id(ent); rcu_read_lock(); memcg = mem_cgroup_lookup(id); if (memcg && !css_tryget(&memcg->css)) @@ -2574,6 +2444,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), nr_pages); unlock_page_cgroup(pc); + WARN_ON_ONCE(PageLRU(page)); /* * "charge_statistics" updated event counter. Then, check it. * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree. @@ -2585,44 +2456,29 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) | (1 << PCG_MOVE_LOCK) |\ - (1 << PCG_ACCT_LRU) | (1 << PCG_MIGRATION)) + (1 << PCG_MIGRATION)) /* * Because tail pages are not marked as "used", set it. We're under - * zone->lru_lock, 'splitting on pmd' and compund_lock. + * zone->lru_lock, 'splitting on pmd' and compound_lock. + * charge/uncharge will be never happen and move_account() is done under + * compound_lock(), so we don't have to take care of races. */ -void mem_cgroup_split_huge_fixup(struct page *head, struct page *tail) +void mem_cgroup_split_huge_fixup(struct page *head) { struct page_cgroup *head_pc = lookup_page_cgroup(head); - struct page_cgroup *tail_pc = lookup_page_cgroup(tail); - unsigned long flags; + struct page_cgroup *pc; + int i; if (mem_cgroup_disabled()) return; - /* - * We have no races with charge/uncharge but will have races with - * page state accounting. - */ - move_lock_page_cgroup(head_pc, &flags); - - tail_pc->mem_cgroup = head_pc->mem_cgroup; - smp_wmb(); /* see __commit_charge() */ - if (PageCgroupAcctLRU(head_pc)) { - enum lru_list lru; - struct mem_cgroup_per_zone *mz; - - /* - * LRU flags cannot be copied because we need to add tail - *.page to LRU by generic call and our hook will be called. - * We hold lru_lock, then, reduce counter directly. - */ - lru = page_lru(head); - mz = page_cgroup_zoneinfo(head_pc->mem_cgroup, head); - MEM_CGROUP_ZSTAT(mz, lru) -= 1; + for (i = 1; i < HPAGE_PMD_NR; i++) { + pc = head_pc + i; + pc->mem_cgroup = head_pc->mem_cgroup; + smp_wmb();/* see __commit_charge() */ + pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT; } - tail_pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT; - move_unlock_page_cgroup(head_pc, &flags); } -#endif +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ /** * mem_cgroup_move_account - move account of the page @@ -2737,7 +2593,7 @@ static int mem_cgroup_move_parent(struct page *page, parent = mem_cgroup_from_cont(pcg); ret = __mem_cgroup_try_charge(NULL, gfp_mask, nr_pages, &parent, false); - if (ret || !parent) + if (ret) goto put_back; if (nr_pages > 1) @@ -2783,12 +2639,9 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, } pc = lookup_page_cgroup(page); - BUG_ON(!pc); /* XXX: remove this and move pc lookup into commit */ - ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &memcg, oom); - if (ret || !memcg) + if (ret == -ENOMEM) return ret; - __mem_cgroup_commit_charge(memcg, page, nr_pages, pc, ctype); return 0; } @@ -2798,19 +2651,11 @@ int mem_cgroup_newpage_charge(struct page *page, { if (mem_cgroup_disabled()) return 0; - /* - * If already mapped, we don't have to account. - * If page cache, page->mapping has address_space. - * But page->mapping may have out-of-use anon_vma pointer, - * detecit it by PageAnon() check. newly-mapped-anon's page->mapping - * is NULL. - */ - if (page_mapped(page) || (page->mapping && !PageAnon(page))) - return 0; - if (unlikely(!mm)) - mm = &init_mm; + VM_BUG_ON(page_mapped(page)); + VM_BUG_ON(page->mapping && !PageAnon(page)); + VM_BUG_ON(!mm); return mem_cgroup_charge_common(page, mm, gfp_mask, - MEM_CGROUP_CHARGE_TYPE_MAPPED); + MEM_CGROUP_CHARGE_TYPE_MAPPED); } static void @@ -2822,14 +2667,27 @@ __mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *memcg, enum charge_type ctype) { struct page_cgroup *pc = lookup_page_cgroup(page); + struct zone *zone = page_zone(page); + unsigned long flags; + bool removed = false; + /* * In some case, SwapCache, FUSE(splice_buf->radixtree), the page * is already on LRU. It means the page may on some other page_cgroup's * LRU. Take care of it. */ - mem_cgroup_lru_del_before_commit(page); + spin_lock_irqsave(&zone->lru_lock, flags); + if (PageLRU(page)) { + del_page_from_lru_list(zone, page, page_lru(page)); + ClearPageLRU(page); + removed = true; + } __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype); - mem_cgroup_lru_add_after_commit(page); + if (removed) { + add_page_to_lru_list(zone, page, page_lru(page)); + SetPageLRU(page); + } + spin_unlock_irqrestore(&zone->lru_lock, flags); return; } @@ -2837,6 +2695,7 @@ int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) { struct mem_cgroup *memcg = NULL; + enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE; int ret; if (mem_cgroup_disabled()) @@ -2846,31 +2705,16 @@ int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, if (unlikely(!mm)) mm = &init_mm; + if (!page_is_file_cache(page)) + type = MEM_CGROUP_CHARGE_TYPE_SHMEM; - if (page_is_file_cache(page)) { - ret = __mem_cgroup_try_charge(mm, gfp_mask, 1, &memcg, true); - if (ret || !memcg) - return ret; - - /* - * FUSE reuses pages without going through the final - * put that would remove them from the LRU list, make - * sure that they get relinked properly. - */ - __mem_cgroup_commit_charge_lrucare(page, memcg, - MEM_CGROUP_CHARGE_TYPE_CACHE); - return ret; - } - /* shmem */ - if (PageSwapCache(page)) { + if (!PageSwapCache(page)) + ret = mem_cgroup_charge_common(page, mm, gfp_mask, type); + else { /* page is swapcache/shmem */ ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &memcg); if (!ret) - __mem_cgroup_commit_charge_swapin(page, memcg, - MEM_CGROUP_CHARGE_TYPE_SHMEM); - } else - ret = mem_cgroup_charge_common(page, mm, gfp_mask, - MEM_CGROUP_CHARGE_TYPE_SHMEM); - + __mem_cgroup_commit_charge_swapin(page, memcg, type); + } return ret; } @@ -2882,12 +2726,12 @@ int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, */ int mem_cgroup_try_charge_swapin(struct mm_struct *mm, struct page *page, - gfp_t mask, struct mem_cgroup **ptr) + gfp_t mask, struct mem_cgroup **memcgp) { struct mem_cgroup *memcg; int ret; - *ptr = NULL; + *memcgp = NULL; if (mem_cgroup_disabled()) return 0; @@ -2905,27 +2749,32 @@ int mem_cgroup_try_charge_swapin(struct mm_struct *mm, memcg = try_get_mem_cgroup_from_page(page); if (!memcg) goto charge_cur_mm; - *ptr = memcg; - ret = __mem_cgroup_try_charge(NULL, mask, 1, ptr, true); + *memcgp = memcg; + ret = __mem_cgroup_try_charge(NULL, mask, 1, memcgp, true); css_put(&memcg->css); + if (ret == -EINTR) + ret = 0; return ret; charge_cur_mm: if (unlikely(!mm)) mm = &init_mm; - return __mem_cgroup_try_charge(mm, mask, 1, ptr, true); + ret = __mem_cgroup_try_charge(mm, mask, 1, memcgp, true); + if (ret == -EINTR) + ret = 0; + return ret; } static void -__mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, +__mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg, enum charge_type ctype) { if (mem_cgroup_disabled()) return; - if (!ptr) + if (!memcg) return; - cgroup_exclude_rmdir(&ptr->css); + cgroup_exclude_rmdir(&memcg->css); - __mem_cgroup_commit_charge_lrucare(page, ptr, ctype); + __mem_cgroup_commit_charge_lrucare(page, memcg, ctype); /* * Now swap is on-memory. This means this page may be * counted both as mem and swap....double count. @@ -2935,21 +2784,22 @@ __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, */ if (do_swap_account && PageSwapCache(page)) { swp_entry_t ent = {.val = page_private(page)}; + struct mem_cgroup *swap_memcg; unsigned short id; - struct mem_cgroup *memcg; id = swap_cgroup_record(ent, 0); rcu_read_lock(); - memcg = mem_cgroup_lookup(id); - if (memcg) { + swap_memcg = mem_cgroup_lookup(id); + if (swap_memcg) { /* * This recorded memcg can be obsolete one. So, avoid * calling css_tryget */ - if (!mem_cgroup_is_root(memcg)) - res_counter_uncharge(&memcg->memsw, PAGE_SIZE); - mem_cgroup_swap_statistics(memcg, false); - mem_cgroup_put(memcg); + if (!mem_cgroup_is_root(swap_memcg)) + res_counter_uncharge(&swap_memcg->memsw, + PAGE_SIZE); + mem_cgroup_swap_statistics(swap_memcg, false); + mem_cgroup_put(swap_memcg); } rcu_read_unlock(); } @@ -2958,13 +2808,14 @@ __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, * 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); + cgroup_release_and_wakeup_rmdir(&memcg->css); } -void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) +void mem_cgroup_commit_charge_swapin(struct page *page, + struct mem_cgroup *memcg) { - __mem_cgroup_commit_charge_swapin(page, ptr, - MEM_CGROUP_CHARGE_TYPE_MAPPED); + __mem_cgroup_commit_charge_swapin(page, memcg, + MEM_CGROUP_CHARGE_TYPE_MAPPED); } void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg) @@ -3054,7 +2905,7 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) * Check if our page_cgroup is valid */ pc = lookup_page_cgroup(page); - if (unlikely(!pc || !PageCgroupUsed(pc))) + if (unlikely(!PageCgroupUsed(pc))) return NULL; lock_page_cgroup(pc); @@ -3117,8 +2968,7 @@ void mem_cgroup_uncharge_page(struct page *page) /* early check. */ if (page_mapped(page)) return; - if (page->mapping && !PageAnon(page)) - return; + VM_BUG_ON(page->mapping && !PageAnon(page)); __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED); } @@ -3176,6 +3026,23 @@ void mem_cgroup_uncharge_end(void) batch->memcg = NULL; } +/* + * A function for resetting pc->mem_cgroup for newly allocated pages. + * This function should be called if the newpage will be added to LRU + * before start accounting. + */ +void mem_cgroup_reset_owner(struct page *newpage) +{ + struct page_cgroup *pc; + + if (mem_cgroup_disabled()) + return; + + pc = lookup_page_cgroup(newpage); + VM_BUG_ON(PageCgroupUsed(pc)); + pc->mem_cgroup = root_mem_cgroup; +} + #ifdef CONFIG_SWAP /* * called after __delete_from_swap_cache() and drop "page" account. @@ -3293,14 +3160,14 @@ static inline int mem_cgroup_move_swap_account(swp_entry_t entry, * page belongs to. */ int mem_cgroup_prepare_migration(struct page *page, - struct page *newpage, struct mem_cgroup **ptr, gfp_t gfp_mask) + struct page *newpage, struct mem_cgroup **memcgp, gfp_t gfp_mask) { struct mem_cgroup *memcg = NULL; struct page_cgroup *pc; enum charge_type ctype; int ret = 0; - *ptr = NULL; + *memcgp = NULL; VM_BUG_ON(PageTransHuge(page)); if (mem_cgroup_disabled()) @@ -3351,10 +3218,10 @@ int mem_cgroup_prepare_migration(struct page *page, if (!memcg) return 0; - *ptr = memcg; - ret = __mem_cgroup_try_charge(NULL, gfp_mask, 1, ptr, false); + *memcgp = memcg; + ret = __mem_cgroup_try_charge(NULL, gfp_mask, 1, memcgp, false); css_put(&memcg->css);/* drop extra refcnt */ - if (ret || *ptr == NULL) { + if (ret) { if (PageAnon(page)) { lock_page_cgroup(pc); ClearPageCgroupMigration(pc); @@ -3364,6 +3231,7 @@ int mem_cgroup_prepare_migration(struct page *page, */ mem_cgroup_uncharge_page(page); } + /* we'll need to revisit this error code (we have -EINTR) */ return -ENOMEM; } /* @@ -3432,12 +3300,51 @@ void mem_cgroup_end_migration(struct mem_cgroup *memcg, cgroup_release_and_wakeup_rmdir(&memcg->css); } +/* + * At replace page cache, newpage is not under any memcg but it's on + * LRU. So, this function doesn't touch res_counter but handles LRU + * in correct way. Both pages are locked so we cannot race with uncharge. + */ +void mem_cgroup_replace_page_cache(struct page *oldpage, + struct page *newpage) +{ + struct mem_cgroup *memcg; + struct page_cgroup *pc; + enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE; + + if (mem_cgroup_disabled()) + return; + + pc = lookup_page_cgroup(oldpage); + /* fix accounting on old pages */ + lock_page_cgroup(pc); + memcg = pc->mem_cgroup; + mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), -1); + ClearPageCgroupUsed(pc); + unlock_page_cgroup(pc); + + if (PageSwapBacked(oldpage)) + type = MEM_CGROUP_CHARGE_TYPE_SHMEM; + + /* + * Even if newpage->mapping was NULL before starting replacement, + * the newpage may be on LRU(or pagevec for LRU) already. We lock + * LRU while we overwrite pc->mem_cgroup. + */ + __mem_cgroup_commit_charge_lrucare(newpage, memcg, type); +} + #ifdef CONFIG_DEBUG_VM static struct page_cgroup *lookup_page_cgroup_used(struct page *page) { struct page_cgroup *pc; pc = lookup_page_cgroup(page); + /* + * Can be NULL while feeding pages into the page allocator for + * the first time, i.e. during boot or memory hotplug; + * or when mem_cgroup_disabled(). + */ if (likely(pc) && PageCgroupUsed(pc)) return pc; return NULL; @@ -3457,23 +3364,8 @@ void mem_cgroup_print_bad_page(struct page *page) pc = lookup_page_cgroup_used(page); if (pc) { - int ret = -1; - char *path; - - printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p", + printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p\n", pc, pc->flags, pc->mem_cgroup); - - path = kmalloc(PATH_MAX, GFP_KERNEL); - if (path) { - rcu_read_lock(); - ret = cgroup_path(pc->mem_cgroup->css.cgroup, - path, PATH_MAX); - rcu_read_unlock(); - } - - printk(KERN_CONT "(%s)\n", - (ret < 0) ? "cannot get the path" : path); - kfree(path); } } #endif @@ -3534,9 +3426,8 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, if (!ret) break; - mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, - MEM_CGROUP_RECLAIM_SHRINK, - NULL); + mem_cgroup_reclaim(memcg, GFP_KERNEL, + MEM_CGROUP_RECLAIM_SHRINK); curusage = res_counter_read_u64(&memcg->res, RES_USAGE); /* Usage is reduced ? */ if (curusage >= oldusage) @@ -3594,10 +3485,9 @@ static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, if (!ret) break; - mem_cgroup_hierarchical_reclaim(memcg, NULL, GFP_KERNEL, - MEM_CGROUP_RECLAIM_NOSWAP | - MEM_CGROUP_RECLAIM_SHRINK, - NULL); + mem_cgroup_reclaim(memcg, GFP_KERNEL, + MEM_CGROUP_RECLAIM_NOSWAP | + MEM_CGROUP_RECLAIM_SHRINK); curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); /* Usage is reduced ? */ if (curusage >= oldusage) @@ -3640,10 +3530,8 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, break; nr_scanned = 0; - reclaimed = mem_cgroup_hierarchical_reclaim(mz->mem, zone, - gfp_mask, - MEM_CGROUP_RECLAIM_SOFT, - &nr_scanned); + reclaimed = mem_cgroup_soft_reclaim(mz->mem, zone, + gfp_mask, &nr_scanned); nr_reclaimed += reclaimed; *total_scanned += nr_scanned; spin_lock(&mctz->lock); @@ -3711,22 +3599,23 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, static int mem_cgroup_force_empty_list(struct mem_cgroup *memcg, int node, int zid, enum lru_list lru) { - struct zone *zone; struct mem_cgroup_per_zone *mz; - struct page_cgroup *pc, *busy; unsigned long flags, loop; struct list_head *list; + struct page *busy; + struct zone *zone; int ret = 0; zone = &NODE_DATA(node)->node_zones[zid]; mz = mem_cgroup_zoneinfo(memcg, node, zid); - list = &mz->lists[lru]; + list = &mz->lruvec.lists[lru]; loop = MEM_CGROUP_ZSTAT(mz, lru); /* give some margin against EBUSY etc...*/ loop += 256; busy = NULL; while (loop--) { + struct page_cgroup *pc; struct page *page; ret = 0; @@ -3735,24 +3624,24 @@ static int mem_cgroup_force_empty_list(struct mem_cgroup *memcg, spin_unlock_irqrestore(&zone->lru_lock, flags); break; } - pc = list_entry(list->prev, struct page_cgroup, lru); - if (busy == pc) { - list_move(&pc->lru, list); + page = list_entry(list->prev, struct page, lru); + if (busy == page) { + list_move(&page->lru, list); busy = NULL; spin_unlock_irqrestore(&zone->lru_lock, flags); continue; } spin_unlock_irqrestore(&zone->lru_lock, flags); - page = lookup_cgroup_page(pc); + pc = lookup_page_cgroup(page); ret = mem_cgroup_move_parent(page, pc, memcg, GFP_KERNEL); - if (ret == -ENOMEM) + if (ret == -ENOMEM || ret == -EINTR) break; if (ret == -EBUSY || ret == -EINVAL) { /* found lock contention or "pc" is obsolete. */ - busy = pc; + busy = page; cond_resched(); } else busy = NULL; @@ -4846,7 +4735,7 @@ static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) for (zone = 0; zone < MAX_NR_ZONES; zone++) { mz = &pn->zoneinfo[zone]; for_each_lru(l) - INIT_LIST_HEAD(&mz->lists[l]); + INIT_LIST_HEAD(&mz->lruvec.lists[l]); mz->usage_in_excess = 0; mz->on_tree = false; mz->mem = memcg; @@ -4906,7 +4795,7 @@ static void __mem_cgroup_free(struct mem_cgroup *memcg) mem_cgroup_remove_from_trees(memcg); free_css_id(&mem_cgroup_subsys, &memcg->css); - for_each_node_state(node, N_POSSIBLE) + for_each_node(node) free_mem_cgroup_per_zone_info(memcg, node); free_percpu(memcg->stat); @@ -4965,13 +4854,13 @@ static int mem_cgroup_soft_limit_tree_init(void) struct mem_cgroup_tree_per_zone *rtpz; int tmp, node, zone; - for_each_node_state(node, N_POSSIBLE) { + for_each_node(node) { tmp = node; if (!node_state(node, N_NORMAL_MEMORY)) tmp = -1; rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, tmp); if (!rtpn) - return 1; + goto err_cleanup; soft_limit_tree.rb_tree_per_node[node] = rtpn; @@ -4982,6 +4871,16 @@ static int mem_cgroup_soft_limit_tree_init(void) } } return 0; + +err_cleanup: + for_each_node(node) { + if (!soft_limit_tree.rb_tree_per_node[node]) + break; + kfree(soft_limit_tree.rb_tree_per_node[node]); + soft_limit_tree.rb_tree_per_node[node] = NULL; + } + return 1; + } static struct cgroup_subsys_state * __ref @@ -4995,7 +4894,7 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) if (!memcg) return ERR_PTR(error); - for_each_node_state(node, N_POSSIBLE) + for_each_node(node) if (alloc_mem_cgroup_per_zone_info(memcg, node)) goto free_out; @@ -5033,7 +4932,6 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) res_counter_init(&memcg->res, NULL); res_counter_init(&memcg->memsw, NULL); } - memcg->last_scanned_child = 0; memcg->last_scanned_node = MAX_NUMNODES; INIT_LIST_HEAD(&memcg->oom_notify); @@ -5129,9 +5027,9 @@ one_by_one: } ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, 1, &memcg, false); - if (ret || !memcg) + if (ret) /* mem_cgroup_clear_mc() will do uncharge later */ - return -ENOMEM; + return ret; mc.precharge++; } return ret; @@ -5276,7 +5174,7 @@ static int is_target_pte_for_mc(struct vm_area_struct *vma, } /* There is a swap entry and a page doesn't exist or isn't charged */ if (ent.val && !ret && - css_id(&mc.from->css) == lookup_swap_cgroup(ent)) { + css_id(&mc.from->css) == lookup_swap_cgroup_id(ent)) { ret = MC_TARGET_SWAP; if (target) target->ent = ent; |