memcg: allow kmem limit to be resized down
The userspace memory limit can be freely resized down. Upon attempt,
reclaim will be called to flush the pages away until we either reach the
limit we want or give up.
It wasn't possible so far with the kmem limit, since we had no way to
shrink the kmem buffers other than using the big hammer of shrink_slab,
that effectively frees data around the whole system.
The situation flips now that we have a per-memcg shrinker
infrastructure. We will proceed analogously to our user memory
counterpart and try to shrink our buffers until we either reach the
limit we want or give up.
Signed-off-by: Glauber Costa <glommer@openvz.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
1 file changed
