mm: memcontrol: convert reclaim iterator to simple css refcounting

The memcg reclaim iterators use a complicated weak reference scheme to
prevent pinning cgroups indefinitely in the absence of memory pressure.

However, during the ongoing cgroup core rework, css lifetime has been
decoupled such that a pinned css no longer interferes with removal of
the user-visible cgroup, and all this complexity is now unnecessary.

[[email protected]: ensure that the cached reference is always released]
Signed-off-by: Johannes Weiner <[email protected]>
Cc: Vladimir Davydov <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Tejun Heo <[email protected]>
Signed-off-by: Michal Hocko <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions