• Michal Hocko's avatar
    memcg, vmscan: do not attempt soft limit reclaim if it would not scan anything · e839b6a1
    Michal Hocko authored
    mem_cgroup_should_soft_reclaim controls whether soft reclaim pass is
    done and it always says yes currently.  Memcg iterators are clever to
    skip nodes that are not soft reclaimable quite efficiently but
    mem_cgroup_should_soft_reclaim can be more clever and do not start the
    soft reclaim pass at all if it knows that nothing would be scanned
    anyway.
    
    In order to do that, simply reuse mem_cgroup_soft_reclaim_eligible for
    the target group of the reclaim and allow the pass only if the whole
    subtree wouldn't be skipped.
    Signed-off-by: default avatarMichal Hocko <mhocko@suse.cz>
    Cc: Balbir Singh <bsingharora@gmail.com>
    Cc: Glauber Costa <glommer@openvz.org>
    Cc: Greg Thelen <gthelen@google.com>
    Cc: Hugh Dickins <hughd@google.com>
    Cc: Johannes Weiner <hannes@cmpxchg.org>
    Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
    Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
    Cc: Michel Lespinasse <walken@google.com>
    Cc: Tejun Heo <tj@kernel.org>
    Cc: Ying Han <yinghan@google.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    e839b6a1
vmscan.c 106 KB