From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A3B901AAA5 for ; Sat, 20 Apr 2024 11:24:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713612256; cv=none; b=nCYz1KWJ1s2frAQM0A3ja4NWmPB9at74mKIyT3Yk8CaC6qB8N99ClZqtbGvSjjuGdhaHf0iC/ww+YVWx7kZt4zedAydJy+qujzPBHHPgOaLiMKOoMbo24f0l+TkMLUU3yibck8VRZfWsbglri3xrFO3ZM9pvgOVyOIiUVDpE4J8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713612256; c=relaxed/simple; bh=7P7QJPWTeWLAxseSS0mBucNx7SkCqdF5PIlnB7gMfYI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=CWq/inwTK0VgIgwqxHFCQBnLPZuW7/8Zo5PENUMM/T/JE2ghkbMrOnM41D8qnhipKmWuBEHAzpsemjdqezxOtFb0xYGFHPZPysu1CAJ3BsOxtKJqGRjbFUcQIB4YcLTxMNHcoGeTIwupMejxCL2HA9j7E7WQt2dPXe3fnSukRfc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=umAABJvq; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="umAABJvq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6EC30C113CC; Sat, 20 Apr 2024 11:24:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1713612256; bh=7P7QJPWTeWLAxseSS0mBucNx7SkCqdF5PIlnB7gMfYI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=umAABJvqjKSPgfHgcf9El2LDnHrpk+6e+tX/qxYrgFSjxQKL9C1fXCe+AE9T7kcol kcmOIs94QFViEdan6vF1Gi4T6cJUrF7tbj434w/thkv7brSY/ZOVbFVBeXY4ANHtpY w5Iwni5YdUMGZS2sTn6rP9I6JPnjMiKjNATpbh4SFZjjR0nJuzAIGYWZLH7ckhUrCk TxNVRWFRIoRCNc2Xh1UAAGtMJq4q4wPdqPy2luv3m22MuqZK3aI7JDwraviepiFxBN SwACWYVFed/fvcF3xN5cjd5NkNLzt2y6bnF6K5VJMeykDsGT0ZcDtck9ndI77tRGmd +hr9eMmdanRTA== From: Geliang Tang To: mptcp@lists.linux.dev Cc: Nicolas Rybowski , Geliang Tang Subject: [PATCH mptcp-next v8 1/4] selftests/bpf: Add mptcp subflow example Date: Sat, 20 Apr 2024 19:23:26 +0800 Message-Id: <740fd7f056ea819f92729cf85f0c0dc66399bd7d.1713612119.git.tanggeliang@kylinos.cn> X-Mailer: git-send-email 2.40.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Nicolas Rybowski Move Nicolas's patch into bpf selftests directory. This example added a test that was adding a different mark (SO_MARK) on each subflow, and changing the TCP CC only on the first subflow. This example shows how it is possible to: Identify the parent msk of an MPTCP subflow. Put different sockopt for each subflow of a same MPTCP connection. Here especially, we implemented two different behaviours: A socket mark (SOL_SOCKET SO_MARK) is put on each subflow of a same MPTCP connection. The order of creation of the current subflow defines its mark. The TCP CC algorithm of the very first subflow of an MPTCP connection is set to "reno". The code comes from commit 4d120186e4d6 ("bpf:examples: update mptcp_set_mark_kern.c") in MPTCP repo https://github.com/multipath-tcp/mptcp_net-next (the "scripts" branch). Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/76 Co-developed-by: Geliang Tang Signed-off-by: Geliang Tang Signed-off-by: Nicolas Rybowski --- .../selftests/bpf/progs/mptcp_subflow.c | 70 +++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/mptcp_subflow.c diff --git a/tools/testing/selftests/bpf/progs/mptcp_subflow.c b/tools/testing/selftests/bpf/progs/mptcp_subflow.c new file mode 100644 index 000000000000..de9dbba37133 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/mptcp_subflow.c @@ -0,0 +1,70 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020, Tessares SA. */ +/* Copyright (c) 2024, Kylin Software */ + +#include // SOL_SOCKET, SO_MARK, ... +#include // TCP_CONGESTION +#include +#include +#include "bpf_tcp_helpers.h" + +char _license[] SEC("license") = "GPL"; + +#ifndef SOL_TCP +#define SOL_TCP 6 +#endif + +#ifndef TCP_CA_NAME_MAX +#define TCP_CA_NAME_MAX 16 +#endif + +char cc[TCP_CA_NAME_MAX] = "reno"; + +/* Associate a subflow counter to each token */ +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(key_size, sizeof(__u32)); + __uint(value_size, sizeof(__u32)); + __uint(max_entries, 100); +} mptcp_sf SEC(".maps"); + +SEC("sockops") +int mptcp_subflow(struct bpf_sock_ops *skops) +{ + __u32 init = 1, key, mark, *cnt; + struct mptcp_sock *msk; + struct bpf_sock *sk; + int err; + + if (skops->op != BPF_SOCK_OPS_TCP_CONNECT_CB) + return 1; + + sk = skops->sk; + if (!sk) + return 1; + + msk = bpf_skc_to_mptcp_sock(sk); + if (!msk) + return 1; + + key = msk->token; + cnt = bpf_map_lookup_elem(&mptcp_sf, &key); + if (cnt) { + /* A new subflow is added to an existing MPTCP connection */ + __sync_fetch_and_add(cnt, 1); + mark = *cnt; + } else { + /* A new MPTCP connection is just initiated and this is its primary subflow */ + bpf_map_update_elem(&mptcp_sf, &key, &init, BPF_ANY); + mark = init; + } + + /* Set the mark of the subflow's socket based on appearance order */ + err = bpf_setsockopt(skops, SOL_SOCKET, SO_MARK, &mark, sizeof(mark)); + if (err < 0) + return 1; + if (mark == 1) + err = bpf_setsockopt(skops, SOL_TCP, TCP_CONGESTION, cc, TCP_CA_NAME_MAX); + + return 1; +} -- 2.40.1