| Message ID | cover.1705427537.git.pabeni@redhat.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | mptcp: annotate lockless access | expand |
On Tue, 16 Jan 2024, Paolo Abeni wrote: > This is the 2nd preparatory series for the TCP_NOTSENT_LOWAT support. > The latter will need tracking more state under the msk data lock > > The mptcp locking schema is already quite complex. We need to clarify > and make consistent the lockless access already there or later changes > will be even harder to follow and understand. > > This series goes through all the msk fields accessed in the RX and TX > path and makes the lockless annotation consistent with the in-use > locking schema. > > As a bonus this should fix data races possibly found by fuzzers - even > if we haven't seen many such reports so far. > > Patch 1/5 hints we could remove local_key and remote_key from the > subflow context, and always use the ones in the msk socket, possibly > reducing the context memory usage. That change is left over as a > possible follow-up. > Thanks for the reply to my question on patch 2, series LGTM: Reviewed-by: Mat Martineau <martineau@kernel.org> > Paolo Abeni (5): > mptcp: annotate access for msk keys > mptcp: annotate lockless access for the tx path > mptcp: annotate lockless access for RX path fields. > mptcp: annotate lockless access for token > mptcp: annotate lockless accesses around read-mostly fields > > net/mptcp/options.c | 20 ++++++++--------- > net/mptcp/pm.c | 2 +- > net/mptcp/pm_netlink.c | 10 ++++----- > net/mptcp/protocol.c | 51 +++++++++++++++++++++--------------------- > net/mptcp/protocol.h | 8 ++++--- > net/mptcp/sockopt.c | 2 +- > net/mptcp/subflow.c | 10 +++++---- > 7 files changed, 54 insertions(+), 49 deletions(-) > > -- > 2.43.0 > > >
Hi Paolo, Mat, On 16/01/2024 19:16, Paolo Abeni wrote: > This is the 2nd preparatory series for the TCP_NOTSENT_LOWAT support. > The latter will need tracking more state under the msk data lock > > The mptcp locking schema is already quite complex. We need to clarify > and make consistent the lockless access already there or later changes > will be even harder to follow and understand. > > This series goes through all the msk fields accessed in the RX and TX > path and makes the lockless annotation consistent with the in-use > locking schema. > > As a bonus this should fix data races possibly found by fuzzers - even > if we haven't seen many such reports so far. > > Patch 1/5 hints we could remove local_key and remote_key from the > subflow context, and always use the ones in the msk socket, possibly > reducing the context memory usage. That change is left over as a > possible follow-up. > > Paolo Abeni (5): > mptcp: annotate access for msk keys > mptcp: annotate lockless access for the tx path > mptcp: annotate lockless access for RX path fields. > mptcp: annotate lockless access for token > mptcp: annotate lockless accesses around read-mostly fields Thank you for the patches and the reviews! Now in our tree (feat. for net-next) without a typo spotted by checkpatch.pl --codespell. New patches for t/upstream: - 39c9cb5e8865: mptcp: annotate access for msk keys - 483c63a2857c: mptcp: annotate lockless access for the tx path - 817a9559ee7c: mptcp: annotate lockless access for RX path fields - 5cda40c71dad: mptcp: annotate lockless access for token - ce87356496c6: mptcp: annotate lockless accesses around read-mostly fields - Results: 81c0f68b0316..2710fa51b8b5 (export) Tests are now in progress: https://cirrus-ci.com/github/multipath-tcp/mptcp_net-next/export/20240130T121817 Cheers, Matt