From 0ab6682a17608e99d976d764d159c1a0b6f55ea5 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 25 Apr 2012 11:03:37 +1000 Subject: [PATCH] memcg: move HugeTLB resource count to parent cgroup on memcg removal Add support for memcg removal with HugeTLB resource usage. Signed-off-by: Aneesh Kumar K.V Cc: KAMEZAWA Hiroyuki Cc: Hillf Danton Cc: Michal Hocko Cc: Andrea Arcangeli Cc: Johannes Weiner Signed-off-by: Andrew Morton --- include/linux/hugetlb.h | 8 +++++ include/linux/memcontrol.h | 14 ++++++++ mm/hugetlb.c | 43 +++++++++++++++++++++++++ mm/memcontrol.c | 65 ++++++++++++++++++++++++++++++++------ 4 files changed, 120 insertions(+), 10 deletions(-) diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index fc226be48625..6b4e273f1f1d 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -343,4 +343,12 @@ static inline unsigned int pages_per_huge_page(struct hstate *h) #define hstate_index(h) 0 #endif +#ifdef CONFIG_MEM_RES_CTLR_HUGETLB +extern int hugetlb_force_memcg_empty(struct cgroup *cgroup); +#else +static inline int hugetlb_force_memcg_empty(struct cgroup *cgroup) +{ + return 0; +} +#endif #endif /* _LINUX_HUGETLB_H */ diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 4f1757420ed9..70317e598bf8 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -460,6 +460,9 @@ extern void mem_cgroup_hugetlb_uncharge_page(int idx, unsigned long nr_pages, extern void mem_cgroup_hugetlb_uncharge_memcg(int idx, unsigned long nr_pages, struct mem_cgroup *memcg); extern int mem_cgroup_hugetlb_file_init(int idx) __init; +extern int mem_cgroup_move_hugetlb_parent(int idx, struct cgroup *cgroup, + struct page *page); +extern bool mem_cgroup_have_hugetlb_usage(struct cgroup *cgroup); #else static inline int @@ -496,6 +499,17 @@ static inline int mem_cgroup_hugetlb_file_init(int idx) return 0; } +static inline int +mem_cgroup_move_hugetlb_parent(int idx, struct cgroup *cgroup, + struct page *page) +{ + return 0; +} + +static inline bool mem_cgroup_have_hugetlb_usage(struct cgroup *cgroup) +{ + return 0; +} #endif /* CONFIG_MEM_RES_CTLR_HUGETLB */ #endif /* _LINUX_MEMCONTROL_H */ diff --git a/mm/hugetlb.c b/mm/hugetlb.c index a195ca55ee90..bf84ae3e6c88 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1909,6 +1909,49 @@ static int __init hugetlb_init(void) } module_init(hugetlb_init); +#ifdef CONFIG_MEM_RES_CTLR_HUGETLB +/* + * Force the memcg to empty the hugetlb resources by moving them to + * the parent cgroup. We can fail if the parent cgroup's limit prevented + * the charging. This should only happen if use_hierarchy is not set. + */ +int hugetlb_force_memcg_empty(struct cgroup *cgroup) +{ + struct hstate *h; + struct page *page; + int ret = 0, idx = 0; + + do { + if (cgroup_task_count(cgroup) || !list_empty(&cgroup->children)) + goto out; + /* + * If the task doing the cgroup_rmdir got a signal + * we don't really need to loop till the hugetlb resource + * usage become zero. + */ + if (signal_pending(current)) { + ret = -EINTR; + goto out; + } + for_each_hstate(h) { + spin_lock(&hugetlb_lock); + list_for_each_entry(page, &h->hugepage_activelist, lru) { + ret = mem_cgroup_move_hugetlb_parent(idx, cgroup, page); + if (ret) { + spin_unlock(&hugetlb_lock); + goto out; + } + } + spin_unlock(&hugetlb_lock); + idx++; + } + cond_resched(); + } while (mem_cgroup_have_hugetlb_usage(cgroup)); +out: + return ret; +} +#endif + /* Should be called on processing a hugepagesz=... option */ void __init hugetlb_add_hstate(unsigned order) { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 1c5e0969362e..6331564ac7bd 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3223,9 +3223,11 @@ static inline int mem_cgroup_move_swap_account(swp_entry_t entry, #endif #ifdef CONFIG_MEM_RES_CTLR_HUGETLB -static bool mem_cgroup_have_hugetlb_usage(struct mem_cgroup *memcg) +bool mem_cgroup_have_hugetlb_usage(struct cgroup *cgroup) { int idx; + struct mem_cgroup *memcg = mem_cgroup_from_cont(cgroup); + for (idx = 0; idx < hugetlb_max_hstate; idx++) { if ((res_counter_read_u64(&memcg->hugepage[idx], RES_USAGE)) > 0) return 1; @@ -3323,10 +3325,54 @@ void mem_cgroup_hugetlb_uncharge_memcg(int idx, unsigned long nr_pages, res_counter_uncharge(&memcg->hugepage[idx], csize); return; } -#else -static bool mem_cgroup_have_hugetlb_usage(struct mem_cgroup *memcg) + +int mem_cgroup_move_hugetlb_parent(int idx, struct cgroup *cgroup, + struct page *page) { - return 0; + struct page_cgroup *pc; + int csize, ret = 0; + struct res_counter *fail_res; + struct cgroup *pcgrp = cgroup->parent; + struct mem_cgroup *parent = mem_cgroup_from_cont(pcgrp); + struct mem_cgroup *memcg = mem_cgroup_from_cont(cgroup); + + if (!get_page_unless_zero(page)) + goto out; + + pc = lookup_page_cgroup(page); + lock_page_cgroup(pc); + if (!PageCgroupUsed(pc) || pc->mem_cgroup != memcg) + goto err_out; + + csize = PAGE_SIZE << compound_order(page); + /* + * If we have use_hierarchy set we can never fail here. So instead of + * using res_counter_uncharge use the open-coded variant which just + * uncharge the child res_counter. The parent will retain the charge. + */ + if (parent->use_hierarchy) { + unsigned long flags; + struct res_counter *counter; + + counter = &memcg->hugepage[idx]; + spin_lock_irqsave(&counter->lock, flags); + res_counter_uncharge_locked(counter, csize); + spin_unlock_irqrestore(&counter->lock, flags); + } else { + ret = res_counter_charge(&parent->hugepage[idx], + csize, &fail_res); + if (ret) { + ret = -EBUSY; + goto err_out; + } + res_counter_uncharge(&memcg->hugepage[idx], csize); + } + pc->mem_cgroup = parent; +err_out: + unlock_page_cgroup(pc); + put_page(page); +out: + return ret; } #endif /* CONFIG_MEM_RES_CTLR_HUGETLB */ @@ -3846,6 +3892,11 @@ static int mem_cgroup_force_empty(struct mem_cgroup *memcg, bool free_all) /* should free all ? */ if (free_all) goto try_to_free; + + /* move the hugetlb charges */ + ret = hugetlb_force_memcg_empty(cgrp); + if (ret) + goto out; move_account: do { ret = -EBUSY; @@ -5170,12 +5221,6 @@ free_out: static int mem_cgroup_pre_destroy(struct cgroup *cont) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); - /* - * Don't allow memcg removal if we have HugeTLB resource - * usage. - */ - if (mem_cgroup_have_hugetlb_usage(memcg)) - return -EBUSY; return mem_cgroup_force_empty(memcg, false); } -- 2.39.5