[PATCH v7 mptcp-next 0/6] mptcp: autotune related improvement

[Paolo Abeni <pabeni@redhat.com>]

This series collects a few follow-up for the backlog refactor, with some
of them posing as fixes just to confuse the enemy.

Targeting net-next as the issues addressed are very old, the change
is quite invasive and, as mentioned, based on the BL refactor.

Overall this:
- introduces a tracepoint similar to tcp useful to track down the issues
  addressed here
- avoid rx drop in corner case scenarios, improving tput stability and
  peak tput over fast link
- refactor the rcv space and rtt estimator, overall making DRS more
  correct and avoiding rcv buffer drifting to tcp_rmem[2], which in
  turn makes the tput more stable and less bursty

Note that after this upstream series will be merged:

https://patchwork.kernel.org/user/todo/netdevbpf/?series=1025209

we want to introduce similar changes in mptcp, too.

I'm sorry for the high frequency spamming; trying to complete this
stuff before ENORESOURCES. Please ignore the previous 2 revisions.
---
v6 -> v7:
   - re added the patches dropped in the last 2 iterations

v5 -> v6:
  - dropped the buggy patch 3/5

v4 -> v5:
  - dropped patch 4/6; it proved to be useless together with new version
    of patch 4/5
  - refactor rtt estimator: use sliding window instead of dropping "too
    high" values

v3 -> v4:
  - dropped already merged patch 1
  - update comment in patch 6/6

v2 -> v3:
  - use __entry->family in patch 1/7
  - more verbose commit message for patch 6/7

v1 -> v2:
  - new patch 1/7
  - old patch 2/4 has been split in 3: 3/7, 4/7 and 5/7
  - refactor both the rcv space init and rtt estimator

Paolo Abeni (6):
  trace: mptcp: add mptcp_rcvbuf_grow tracepoint
  mptcp: do not account for OoO in mptcp_rcvbuf_grow()
  mptcp: fix receive space timestamp initialization.
  mptcp: consolidate rcv space init
  mptcp: better mptcp-level RTT estimator
  mptcp: add receive queue awareness in tcp_rcv_space_adjust()

 include/trace/events/mptcp.h |  80 ++++++++++++++++++++++++
 net/mptcp/protocol.c         | 116 ++++++++++++++++++-----------------
 net/mptcp/protocol.h         |  44 ++++++++++++-
 net/mptcp/subflow.c          |   2 -
 4 files changed, 183 insertions(+), 59 deletions(-)

-- 
2.51.1