Add swap accounting to cgroup2

Hi,

This is v2 of the patch set introducing swap accounting to cgroup2. For a detailed description and rationale please see patches 1 and 7.

v1 can be found here: https://lwn.net/Articles/667472/

v2 mostly addresses comments by Johannes. For the detailed changelog, see individual patches.

Thanks,

Vladimir Davydov (7):
mm: memcontrol: charge swap to cgroup2
mm: vmscan: pass memcg to get_scan_count()
mm: memcontrol: replace mem_cgroup_lruvec_online with
mem_cgroup_online
swap.h: move memcg related stuff to the end of the file
mm: vmscan: do not scan anon pages if memcg swap limit is hit
mm: free swap cache aggressively if memcg swap is full
Documentation: cgroup: add memory.swap.{current,max} description

 Documentation/cgroup.txt   |  33 ++++++++++
 include/linux/memcontrol.h |  28 ++++-----
 include/linux/swap.h       |  76 ++++++++++++++--------
 mm/memcontrol.c            | 154 ++++++++++++++++++++++++++++++++++++++++++---
 mm/memory.c                |   3 +-
 mm/shmem.c                 |   4 ++
 mm/swap_state.c            |   5 ++
 mm/swapfile.c              |   6 +-
 mm/vmscan.c                |  26 ++++----
 9 files changed, 265 insertions(+), 70 deletions(-)

2.1.4