diff options
| -rw-r--r-- | include/linux/memcontrol.h | 9 | ||||
| -rw-r--r-- | mm/memcontrol.c | 48 |
2 files changed, 13 insertions, 44 deletions
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index f56c818e56bc..ad800e62cb7a 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -305,11 +305,9 @@ struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *); struct lruvec *mem_cgroup_page_lruvec(struct page *, struct zone *); bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg); - -struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page); struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p); - struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg); + static inline struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css){ return css ? container_of(css, struct mem_cgroup, css) : NULL; @@ -556,11 +554,6 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page, return &zone->lruvec; } -static inline struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) -{ - return NULL; -} - static inline bool mm_match_cgroup(struct mm_struct *mm, struct mem_cgroup *memcg) { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 01009726d412..6ddaeba34e09 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2099,40 +2099,6 @@ static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) css_put_many(&memcg->css, nr_pages); } -/* - * try_get_mem_cgroup_from_page - look up page's memcg association - * @page: the page - * - * Look up, get a css reference, and return the memcg that owns @page. - * - * The page must be locked to prevent racing with swap-in and page - * cache charges. If coming from an unlocked page table, the caller - * must ensure the page is on the LRU or this can race with charging. - */ -struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) -{ - struct mem_cgroup *memcg; - unsigned short id; - swp_entry_t ent; - - VM_BUG_ON_PAGE(!PageLocked(page), page); - - memcg = page->mem_cgroup; - if (memcg) { - if (!css_tryget_online(&memcg->css)) - memcg = NULL; - } else if (PageSwapCache(page)) { - ent.val = page_private(page); - id = lookup_swap_cgroup_id(ent); - rcu_read_lock(); - memcg = mem_cgroup_from_id(id); - if (memcg && !css_tryget_online(&memcg->css)) - memcg = NULL; - rcu_read_unlock(); - } - return memcg; -} - static void lock_page_lru(struct page *page, int *isolated) { struct zone *zone = page_zone(page); @@ -5329,8 +5295,20 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm, * the page lock, which serializes swap cache removal, which * in turn serializes uncharging. */ + VM_BUG_ON_PAGE(!PageLocked(page), page); if (page->mem_cgroup) goto out; + + if (do_swap_account) { + swp_entry_t ent = { .val = page_private(page), }; + unsigned short id = lookup_swap_cgroup_id(ent); + + rcu_read_lock(); + memcg = mem_cgroup_from_id(id); + if (memcg && !css_tryget_online(&memcg->css)) + memcg = NULL; + rcu_read_unlock(); + } } if (PageTransHuge(page)) { @@ -5338,8 +5316,6 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm, VM_BUG_ON_PAGE(!PageTransHuge(page), page); } - if (do_swap_account && PageSwapCache(page)) - memcg = try_get_mem_cgroup_from_page(page); if (!memcg) memcg = get_mem_cgroup_from_mm(mm); |