From 62cccb8c8e7a3ca233f49d5e7dcb1557d25465cd Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Tue, 15 Mar 2016 14:57:22 -0700 Subject: mm: simplify lock_page_memcg() Now that migration doesn't clear page->mem_cgroup of live pages anymore, it's safe to make lock_page_memcg() and the memcg stat functions take pages, and spare the callers from memcg objects. [akpm@linux-foundation.org: fix warnings] Signed-off-by: Johannes Weiner Suggested-by: Vladimir Davydov Acked-by: Vladimir Davydov Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 35 +++++++++++++++++------------------ 1 file changed, 17 insertions(+), 18 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index c45ab3fb6e04..d560c9a3cadf 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -455,42 +455,42 @@ bool mem_cgroup_oom_synchronize(bool wait); extern int do_swap_account; #endif -struct mem_cgroup *lock_page_memcg(struct page *page); -void unlock_page_memcg(struct mem_cgroup *memcg); +void lock_page_memcg(struct page *page); +void unlock_page_memcg(struct page *page); /** * mem_cgroup_update_page_stat - update page state statistics - * @memcg: memcg to account against + * @page: the page * @idx: page state item to account * @val: number of pages (positive or negative) * * Callers must use lock_page_memcg() to prevent double accounting * when the page is concurrently being moved to another memcg: * - * memcg = lock_page_memcg(page); + * lock_page_memcg(page); * if (TestClearPageState(page)) - * mem_cgroup_update_page_stat(memcg, state, -1); - * unlock_page_memcg(memcg); + * mem_cgroup_update_page_stat(page, state, -1); + * unlock_page_memcg(page); */ -static inline void mem_cgroup_update_page_stat(struct mem_cgroup *memcg, +static inline void mem_cgroup_update_page_stat(struct page *page, enum mem_cgroup_stat_index idx, int val) { VM_BUG_ON(!rcu_read_lock_held()); - if (memcg) - this_cpu_add(memcg->stat->count[idx], val); + if (page->mem_cgroup) + this_cpu_add(page->mem_cgroup->stat->count[idx], val); } -static inline void mem_cgroup_inc_page_stat(struct mem_cgroup *memcg, +static inline void mem_cgroup_inc_page_stat(struct page *page, enum mem_cgroup_stat_index idx) { - mem_cgroup_update_page_stat(memcg, idx, 1); + mem_cgroup_update_page_stat(page, idx, 1); } -static inline void mem_cgroup_dec_page_stat(struct mem_cgroup *memcg, +static inline void mem_cgroup_dec_page_stat(struct page *page, enum mem_cgroup_stat_index idx) { - mem_cgroup_update_page_stat(memcg, idx, -1); + mem_cgroup_update_page_stat(page, idx, -1); } unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, @@ -661,12 +661,11 @@ mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) { } -static inline struct mem_cgroup *lock_page_memcg(struct page *page) +static inline void lock_page_memcg(struct page *page) { - return NULL; } -static inline void unlock_page_memcg(struct mem_cgroup *memcg) +static inline void unlock_page_memcg(struct page *page) { } @@ -692,12 +691,12 @@ static inline bool mem_cgroup_oom_synchronize(bool wait) return false; } -static inline void mem_cgroup_inc_page_stat(struct mem_cgroup *memcg, +static inline void mem_cgroup_inc_page_stat(struct page *page, enum mem_cgroup_stat_index idx) { } -static inline void mem_cgroup_dec_page_stat(struct mem_cgroup *memcg, +static inline void mem_cgroup_dec_page_stat(struct page *page, enum mem_cgroup_stat_index idx) { } -- cgit