From e42d9d5d47961fb5db0be65b56dd52fe7b2421f1 Mon Sep 17 00:00:00 2001 From: Wu Fengguang Date: Wed, 16 Dec 2009 12:19:59 +0100 Subject: memcg: rename and export try_get_mem_cgroup_from_page() So that the hwpoison injector can get mem_cgroup for arbitrary page and thus know whether it is owned by some mem_cgroup task(s). [AK: Merged with latest git tree] CC: KOSAKI Motohiro CC: Hugh Dickins CC: Daisuke Nishimura CC: Balbir Singh Acked-by: KAMEZAWA Hiroyuki Signed-off-by: Wu Fengguang Signed-off-by: Andi Kleen --- mm/memcontrol.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) (limited to 'mm/memcontrol.c') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index e0c2066495e3..b5ac61ce7346 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1379,25 +1379,22 @@ static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) return container_of(css, struct mem_cgroup, css); } -static struct mem_cgroup *try_get_mem_cgroup_from_swapcache(struct page *page) +struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) { - struct mem_cgroup *mem; + struct mem_cgroup *mem = NULL; struct page_cgroup *pc; unsigned short id; swp_entry_t ent; VM_BUG_ON(!PageLocked(page)); - if (!PageSwapCache(page)) - return NULL; - pc = lookup_page_cgroup(page); lock_page_cgroup(pc); if (PageCgroupUsed(pc)) { mem = pc->mem_cgroup; if (mem && !css_tryget(&mem->css)) mem = NULL; - } else { + } else if (PageSwapCache(page)) { ent.val = page_private(page); id = lookup_swap_cgroup(ent); rcu_read_lock(); @@ -1743,7 +1740,7 @@ int mem_cgroup_try_charge_swapin(struct mm_struct *mm, */ if (!PageSwapCache(page)) goto charge_cur_mm; - mem = try_get_mem_cgroup_from_swapcache(page); + mem = try_get_mem_cgroup_from_page(page); if (!mem) goto charge_cur_mm; *ptr = mem; -- cgit v1.2.3-59-g8ed1b