From patchwork Mon May 25 18:15:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Westphal X-Patchwork-Id: 218582 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D473DC433DF for ; Mon, 25 May 2020 18:15:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BAF912071C for ; Mon, 25 May 2020 18:15:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388630AbgEYSPd (ORCPT ); Mon, 25 May 2020 14:15:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53500 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387644AbgEYSPc (ORCPT ); Mon, 25 May 2020 14:15:32 -0400 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:12e:520::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6532AC061A0E for ; Mon, 25 May 2020 11:15:32 -0700 (PDT) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1jdHdK-0007l9-Od; Mon, 25 May 2020 20:15:30 +0200 From: Florian Westphal To: Cc: matthieu.baerts@tessares.net, mathew.j.martineau@linux.intel.com, Paolo Abeni , Florian Westphal Subject: [PATCH v2 net-next 2/2] mptcp: move recbuf adjustment to recvmsg path Date: Mon, 25 May 2020 20:15:08 +0200 Message-Id: <20200525181508.13492-3-fw@strlen.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200525181508.13492-1-fw@strlen.de> References: <20200525181508.13492-1-fw@strlen.de> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Paolo Abeni Place receive window tuning in the recvmsg path. This makes sure the size is only increased when userspace consumes data. Previously we would grow the sk receive buffer towards tcp_rmem[2], now we so only if userspace reads data. Simply adjust the msk rcvbuf size to the largest receive buffer of any of the existing subflows. Signed-off-by: Paolo Abeni Signed-off-by: Florian Westphal --- This patch is new in v2. net/mptcp/protocol.c | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index dbb86cbb9e77..89a35c3fc499 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -190,13 +190,6 @@ static bool __mptcp_move_skbs_from_subflow(struct mptcp_sock *msk, return false; } - if (!(sk->sk_userlocks & SOCK_RCVBUF_LOCK)) { - int rcvbuf = max(ssk->sk_rcvbuf, sk->sk_rcvbuf); - - if (rcvbuf > sk->sk_rcvbuf) - sk->sk_rcvbuf = rcvbuf; - } - tp = tcp_sk(ssk); do { u32 map_remaining, offset; @@ -933,6 +926,25 @@ static bool __mptcp_move_skbs(struct mptcp_sock *msk) return moved > 0; } +static void mptcp_rcv_space_adjust(struct mptcp_sock *msk) +{ + const struct mptcp_subflow_context *subflow; + struct sock *sk = (struct sock *)msk; + const struct sock *ssk; + int rcvbuf = 0; + + if (sk->sk_userlocks & SOCK_RCVBUF_LOCK) + return; + + mptcp_for_each_subflow(msk, subflow) { + ssk = mptcp_subflow_tcp_sock(subflow); + rcvbuf = max(ssk->sk_rcvbuf, rcvbuf); + } + + if (rcvbuf) + sk->sk_rcvbuf = rcvbuf; +} + static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock, int flags, int *addr_len) { @@ -962,6 +974,8 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); __mptcp_flush_join_list(msk); + mptcp_rcv_space_adjust(msk); + while (len > (size_t)copied) { int bytes_read; @@ -975,8 +989,10 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, copied += bytes_read; if (skb_queue_empty(&sk->sk_receive_queue) && - __mptcp_move_skbs(msk)) + __mptcp_move_skbs(msk)) { + mptcp_rcv_space_adjust(msk); continue; + } /* only the master socket status is relevant here. The exit * conditions mirror closely tcp_recvmsg()