From 8005184fd1ca6aeb3fea36f4eb9463fc1b90c114 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Mon, 23 Oct 2023 13:44:42 -0700 Subject: mptcp: refactor sndbuf auto-tuning The MPTCP protocol account for the data enqueued on all the subflows to the main socket send buffer, while the send buffer auto-tuning algorithm set the main socket send buffer size as the max size among the subflows. That causes bad performances when at least one subflow is sndbuf limited, e.g. due to very high latency, as the MPTCP scheduler can't even fill such buffer. Change the send-buffer auto-tuning algorithm to compute the main socket send buffer size as the sum of all the subflows buffer size. Reviewed-by: Mat Martineau Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Link: https://lore.kernel.org/r/20231023-send-net-next-20231023-2-v1-9-9dc60939d371@kernel.org Signed-off-by: Jakub Kicinski --- net/mptcp/sockopt.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'net/mptcp/sockopt.c') diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c index 72858d7d8974..574e221bb765 100644 --- a/net/mptcp/sockopt.c +++ b/net/mptcp/sockopt.c @@ -95,6 +95,7 @@ static void mptcp_sol_socket_sync_intval(struct mptcp_sock *msk, int optname, in case SO_SNDBUFFORCE: ssk->sk_userlocks |= SOCK_SNDBUF_LOCK; WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf); + mptcp_subflow_ctx(ssk)->cached_sndbuf = sk->sk_sndbuf; break; case SO_RCVBUF: case SO_RCVBUFFORCE: @@ -1415,8 +1416,10 @@ static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk) if (sk->sk_userlocks & tx_rx_locks) { ssk->sk_userlocks |= sk->sk_userlocks & tx_rx_locks; - if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) + if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) { WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf); + mptcp_subflow_ctx(ssk)->cached_sndbuf = sk->sk_sndbuf; + } if (sk->sk_userlocks & SOCK_RCVBUF_LOCK) WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf); } -- cgit v1.2.3