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 <kosaki.motohiro@jp.fujitsu.com>
CC: Hugh Dickins <hugh.dickins@tiscali.co.uk>
CC: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
CC: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
This commit is contained in:
Wu Fengguang 2009-12-16 12:19:59 +01:00 committed by Andi Kleen
parent 478c5ffc0b
commit e42d9d5d47
2 changed files with 10 additions and 7 deletions

View file

@ -68,6 +68,7 @@ extern unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
extern void mem_cgroup_out_of_memory(struct mem_cgroup *mem, gfp_t gfp_mask);
int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem);
extern struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page);
extern struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
static inline
@ -189,6 +190,11 @@ mem_cgroup_move_lists(struct page *page, enum lru_list from, enum lru_list to)
{
}
static inline struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
{
return NULL;
}
static inline int mm_match_cgroup(struct mm_struct *mm, struct mem_cgroup *mem)
{
return 1;

View file

@ -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;