From a3032a2c15c6967f9f0c0c28375b1a5c833a3112 Mon Sep 17 00:00:00 2001 From: Daisuke Nishimura Date: Tue, 15 Dec 2009 16:47:10 -0800 Subject: [PATCH] memcg: add mem_cgroup_cancel_charge() There are some places calling both res_counter_uncharge() and css_put() to cancel the charge and the refcnt we have got by mem_cgroup_tyr_charge(). This patch introduces mem_cgroup_cancel_charge() and call it in those places. Signed-off-by: KAMEZAWA Hiroyuki Signed-off-by: Daisuke Nishimura Reviewed-by: Balbir Singh Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 38 ++++++++++++++++++-------------------- 1 file changed, 18 insertions(+), 20 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 0b3efb843a87..2d6b4a912a6d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1499,6 +1499,21 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm, return -ENOMEM; } +/* + * Somemtimes we have to undo a charge we got by try_charge(). + * This function is for that and do uncharge, put css's refcnt. + * gotten by try_charge(). + */ +static void mem_cgroup_cancel_charge(struct mem_cgroup *mem) +{ + if (!mem_cgroup_is_root(mem)) { + res_counter_uncharge(&mem->res, PAGE_SIZE); + if (do_swap_account) + res_counter_uncharge(&mem->memsw, PAGE_SIZE); + } + css_put(&mem->css); +} + /* * 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 @@ -1565,12 +1580,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *mem, lock_page_cgroup(pc); if (unlikely(PageCgroupUsed(pc))) { unlock_page_cgroup(pc); - if (!mem_cgroup_is_root(mem)) { - res_counter_uncharge(&mem->res, PAGE_SIZE); - if (do_swap_account) - res_counter_uncharge(&mem->memsw, PAGE_SIZE); - } - css_put(&mem->css); + mem_cgroup_cancel_charge(mem); return; } @@ -1734,14 +1744,7 @@ static int mem_cgroup_move_parent(struct page_cgroup *pc, cancel: put_page(page); uncharge: - /* drop extra refcnt by try_charge() */ - css_put(&parent->css); - /* uncharge if move fails */ - if (!mem_cgroup_is_root(parent)) { - res_counter_uncharge(&parent->res, PAGE_SIZE); - if (do_swap_account) - res_counter_uncharge(&parent->memsw, PAGE_SIZE); - } + mem_cgroup_cancel_charge(parent); return ret; } @@ -1958,12 +1961,7 @@ void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem) return; if (!mem) return; - if (!mem_cgroup_is_root(mem)) { - res_counter_uncharge(&mem->res, PAGE_SIZE); - if (do_swap_account) - res_counter_uncharge(&mem->memsw, PAGE_SIZE); - } - css_put(&mem->css); + mem_cgroup_cancel_charge(mem); } static void