This series improves MPTCP handling of multiple concurrent xmit streams. The to-be-transmitted data is enqueued to a subflow only when the send window is open, keeping the subflows xmit queue shorter and allowing for faster switch-over.
The above requires a more accurate msk socket state tracking and some additional infrastructure to allow pushing the data pending in the msk xmit queue as soon as the MPTCP's send window opens (patches 6-10). As a side effect, the MPTCP socket could enqueue data to subflows after close() time - to completely spooling the data sitting in the msk xmit queue. Dealing with the requires some infrastructure and core TCP changes (patches 1-5) Finally, patches 11-12 introduce a more accurate tracking of the other end's receive window. Overall this refactor the MPTCP xmit path, without introducing new features - the new code is covered by the existing self-tests. Florian Westphal (2): mptcp: rework poll+nospace handling mptcp: keep track of advertised windows right edge Paolo Abeni (11): tcp: factor out tcp_build_frag() mptcp: use tcp_build_frag() tcp: factor out __tcp_close() helper mptcp: introduce mptcp_schedule_work mptcp: reduce the arguments of mptcp_sendmsg_frag mptcp: add accounting for pending data mptcp: introduce MPTCP snd_nxt mptcp: refactor shutdown and close mptcp: move page frag allocation in mptcp_sendmsg() mptcp: try to push pending data on snd una updates mptcp: send explicit ack on delayed ack_seq incr include/net/tcp.h | 4 + net/ipv4/tcp.c | 128 +++--- net/mptcp/options.c | 30 +- net/mptcp/pm.c | 3 +- net/mptcp/pm_netlink.c | 6 +- net/mptcp/protocol.c | 969 ++++++++++++++++++++++++----------------- net/mptcp/protocol.h | 72 ++- net/mptcp/subflow.c | 33 +- 8 files changed, 758 insertions(+), 487 deletions(-) -- 2.26.2
