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 <hannes@cmpxchg.org>
Suggested-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/rmap.c b/mm/rmap.c
index 2871e7d..02f0bfc 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1287,21 +1287,17 @@
*/
void page_add_file_rmap(struct page *page)
{
- struct mem_cgroup *memcg;
-
- memcg = lock_page_memcg(page);
+ lock_page_memcg(page);
if (atomic_inc_and_test(&page->_mapcount)) {
__inc_zone_page_state(page, NR_FILE_MAPPED);
- mem_cgroup_inc_page_stat(memcg, MEM_CGROUP_STAT_FILE_MAPPED);
+ mem_cgroup_inc_page_stat(page, MEM_CGROUP_STAT_FILE_MAPPED);
}
- unlock_page_memcg(memcg);
+ unlock_page_memcg(page);
}
static void page_remove_file_rmap(struct page *page)
{
- struct mem_cgroup *memcg;
-
- memcg = lock_page_memcg(page);
+ lock_page_memcg(page);
/* Hugepages are not counted in NR_FILE_MAPPED for now. */
if (unlikely(PageHuge(page))) {
@@ -1320,12 +1316,12 @@
* pte lock(a spinlock) is held, which implies preemption disabled.
*/
__dec_zone_page_state(page, NR_FILE_MAPPED);
- mem_cgroup_dec_page_stat(memcg, MEM_CGROUP_STAT_FILE_MAPPED);
+ mem_cgroup_dec_page_stat(page, MEM_CGROUP_STAT_FILE_MAPPED);
if (unlikely(PageMlocked(page)))
clear_page_mlock(page);
out:
- unlock_page_memcg(memcg);
+ unlock_page_memcg(page);
}
static void page_remove_anon_compound_rmap(struct page *page)