WRT to the previous iteration, this clean-up patch 2/4 dropping the
left over 'use_backup' field, as suggested by Mat. No other change 

Relevant bits from the previous cover letter:

There are still some sporadic self-test failures for assimetric links.
Looks like they are caused by retransmissions/receiver dropping packets
due to MPTCP level OoO check.

I'll try to address that asap, but I still consider this series for
inclusion, so that it can stage a bit in the export branch.

Note: the last patch re-introduces the workqueue usage for the datapath (yes,
it makes me feel sick, sad and tired :(. I was unable to avoid it.


Paolo Abeni (4):
  mptcp: always graft subflow socket to parent.
  mptcp: re-enable sndbuf autotune
  mptcp: do not queue excessive data on subflows.
  mptcp: schedule work for better snd subflow selection

 net/mptcp/protocol.c | 104 +++++++++++++++++--------------------------
 net/mptcp/protocol.h |  20 +++++++++
 net/mptcp/subflow.c  |  13 +++++-
 3 files changed, 73 insertions(+), 64 deletions(-)

-- 
2.26.2