[PATCH v2 net-next 0/5] mptcp: re-enable sndbuf autotune

The sendbuffer autotuning was unintentionally disabled as a
side effect of the recent workqueue removal refactor. These
patches re-enable id, with some extra care: with autotuning
enable/large send buffer we need a more accurate packet
scheduler to be able to use efficiently the available
subflow bandwidth, especially when the subflows have
different capacities.

The first patch cleans-up subflow socket handling, making
the actual re-enable (patch 2) simpler.

Patches 3 and 4 improve the packet scheduler, to better cope
with non trivial scenarios and large send buffer. 

Finally patch 5 adds and uses some infrastructure to avoid
the workqueue usage for the packet scheduler operations introduced
by the previous patches.

v1 -> v2:
 - fix a UaF in patch 5, see patch changelog for the details 

Paolo Abeni (5):
  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
  mptcp: implement delegated actions

 net/mptcp/protocol.c | 179 ++++++++++++++++++++++++++++---------------
 net/mptcp/protocol.h |  87 +++++++++++++++++++++
 net/mptcp/subflow.c  |  55 ++++++++++++-
 3 files changed, 258 insertions(+), 63 deletions(-)

-- 
2.26.2