On Fri, Jan 29, 2016 at 12:54:03PM -0500, Johannes Weiner wrote:

So far the only sites that needed to exclude charge migration to
stabilize page->mem_cgroup have been per-cgroup page statistics, hence
the name mem_cgroup_begin_page_stat(). But per-cgroup thrash detection
will add another site that needs to ensure page->mem_cgroup lifetime.

Rename these locking functions to the more generic lock_page_memcg()
and unlock_page_memcg(). Since charge migration is a cgroup1 feature
only, we might be able to delete it at some point, and these now easy
to identify locking sites along with it.

Suggested-by: Vladimir Davydov <redacted>
Signed-off-by: Johannes Weiner <redacted>

Acked-by: Vladimir Davydov <redacted>