From: Paolo Abeni pabeni@redhat.com
After the blamed commit below, the send buffer auto-tuning can happen after that the mptcp_propagate_sndbuf() completes - via the delegated action infrastructure.
We must check for write space even after such change or we risk missing the wake-up event.
Fixes: 8005184fd1ca ("mptcp: refactor sndbuf auto-tuning") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni pabeni@redhat.com Reviewed-by: Mat Martineau martineau@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org --- net/mptcp/protocol.h | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-)
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 631a7f445f34..07f6242afc1a 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -790,6 +790,16 @@ static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); }
+static inline void mptcp_write_space(struct sock *sk) +{ + if (sk_stream_is_writeable(sk)) { + /* pairs with memory barrier in mptcp_poll */ + smp_mb(); + if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) + sk_stream_write_space(sk); + } +} + static inline void __mptcp_sync_sndbuf(struct sock *sk) { struct mptcp_subflow_context *subflow; @@ -808,6 +818,7 @@ static inline void __mptcp_sync_sndbuf(struct sock *sk)
/* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */ WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); + mptcp_write_space(sk); }
/* The called held both the msk socket and the subflow socket locks, @@ -838,16 +849,6 @@ static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) local_bh_enable(); }
-static inline void mptcp_write_space(struct sock *sk) -{ - if (sk_stream_is_writeable(sk)) { - /* pairs with memory barrier in mptcp_poll */ - smp_mb(); - if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) - sk_stream_write_space(sk); - } -} - void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags);
#define MPTCP_TOKEN_MAX_RETRIES 4