From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4FEEDC7EE33 for ; Fri, 3 Mar 2023 01:21:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229540AbjCCBVq (ORCPT ); Thu, 2 Mar 2023 20:21:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58866 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229600AbjCCBVq (ORCPT ); Thu, 2 Mar 2023 20:21:46 -0500 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4EDEE521FB for ; Thu, 2 Mar 2023 17:21:44 -0800 (PST) Received: from pps.filterd (m0044010.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 322N6m8g022241 for ; Thu, 2 Mar 2023 17:21:44 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=meta.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=s2048-2021-q4; bh=sKLIlEMkzgw3EOwGlhOKMR1QQhRCdfug2p6qaP/CTdU=; b=nxXeV7HnK0O+mKc+5fUczPx7P4HGAgtp3KMFfejRjEf1he5kNLKzCBx2U83qaTczC8un b1AbibIajtySHe++peG771IfqAj78JikHZeMSrlgrwo8pQyBRXJt5jHHNgxrwQ2h/9aL vtiVgcn30MX1YMrlA0pex9lgG7/OsK/U+NlZ7F8Lxu3pOi5znof+O8S2Ve8yALYCszx6 wIkglluAk73lcLEj8HZ7KE4lagaEDQ0hpBF6VtN15ZA9EsJ9Eqbb5XYSQUKaZV1DRWlW JHglauEaei0KCQesGjVU8MTUjwGBkaXw/3sWgLLKBt4ZDisYlNKHaPg76lJKvzS7gX+w gw== Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3p2xg6m0ty-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 02 Mar 2023 17:21:43 -0800 Received: from twshared33736.38.frc1.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::d) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.17; Thu, 2 Mar 2023 17:21:42 -0800 Received: by devbig931.frc1.facebook.com (Postfix, from userid 460691) id B2AE86644D86; Thu, 2 Mar 2023 17:21:30 -0800 (PST) From: Kui-Feng Lee To: , , , , , , CC: Kui-Feng Lee Subject: [PATCH bpf-next v3 3/8] net: Update an existing TCP congestion control algorithm. Date: Thu, 2 Mar 2023 17:21:17 -0800 Message-ID: <20230303012122.852654-4-kuifeng@meta.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230303012122.852654-1-kuifeng@meta.com> References: <20230303012122.852654-1-kuifeng@meta.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-GUID: u8BtiP9y_9cFuiBXuFM236dVtKd1mUZl X-Proofpoint-ORIG-GUID: u8BtiP9y_9cFuiBXuFM236dVtKd1mUZl X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.219,Aquarius:18.0.942,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-03-02_16,2023-03-02_02,2023-02-09_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org This feature lets you immediately transition to another congestion control algorithm or implementation with the same name. Once a name is updated, new connections will apply this new algorithm. Signed-off-by: Kui-Feng Lee --- include/linux/bpf.h | 1 + include/net/tcp.h | 2 ++ net/bpf/bpf_dummy_struct_ops.c | 6 ++++ net/ipv4/bpf_tcp_ca.c | 8 +++-- net/ipv4/tcp_cong.c | 57 +++++++++++++++++++++++++++++----- 5 files changed, 65 insertions(+), 9 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index b845be719422..acb18aa64b77 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1452,6 +1452,7 @@ struct bpf_struct_ops { void *kdata, const void *udata); int (*reg)(void *kdata); void (*unreg)(void *kdata); + int (*update)(void *kdata, void *old_kdata); const struct btf_type *type; const struct btf_type *value_type; const char *name; diff --git a/include/net/tcp.h b/include/net/tcp.h index db9f828e9d1e..239cc0e2639c 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1117,6 +1117,8 @@ struct tcp_congestion_ops { =20 int tcp_register_congestion_control(struct tcp_congestion_ops *type); void tcp_unregister_congestion_control(struct tcp_congestion_ops *type); +int tcp_update_congestion_control(struct tcp_congestion_ops *type, + struct tcp_congestion_ops *old_type); =20 void tcp_assign_congestion_control(struct sock *sk); void tcp_init_congestion_control(struct sock *sk); diff --git a/net/bpf/bpf_dummy_struct_ops.c b/net/bpf/bpf_dummy_struct_op= s.c index ff4f89a2b02a..158f14e240d0 100644 --- a/net/bpf/bpf_dummy_struct_ops.c +++ b/net/bpf/bpf_dummy_struct_ops.c @@ -222,12 +222,18 @@ static void bpf_dummy_unreg(void *kdata) { } =20 +static int bpf_dummy_update(void *kdata, void *old_kdata) +{ + return -EOPNOTSUPP; +} + struct bpf_struct_ops bpf_bpf_dummy_ops =3D { .verifier_ops =3D &bpf_dummy_verifier_ops, .init =3D bpf_dummy_init, .check_member =3D bpf_dummy_ops_check_member, .init_member =3D bpf_dummy_init_member, .reg =3D bpf_dummy_reg, + .update =3D bpf_dummy_update, .unreg =3D bpf_dummy_unreg, .name =3D "bpf_dummy_ops", }; diff --git a/net/ipv4/bpf_tcp_ca.c b/net/ipv4/bpf_tcp_ca.c index 13fc0c185cd9..558b01d5250f 100644 --- a/net/ipv4/bpf_tcp_ca.c +++ b/net/ipv4/bpf_tcp_ca.c @@ -239,8 +239,6 @@ static int bpf_tcp_ca_init_member(const struct btf_ty= pe *t, if (bpf_obj_name_cpy(tcp_ca->name, utcp_ca->name, sizeof(tcp_ca->name)) <=3D 0) return -EINVAL; - if (tcp_ca_find(utcp_ca->name)) - return -EEXIST; return 1; } =20 @@ -266,10 +264,16 @@ static void bpf_tcp_ca_unreg(void *kdata) tcp_unregister_congestion_control(kdata); } =20 +static int bpf_tcp_ca_update(void *kdata, void *old_kdata) +{ + return tcp_update_congestion_control(kdata, old_kdata); +} + struct bpf_struct_ops bpf_tcp_congestion_ops =3D { .verifier_ops =3D &bpf_tcp_ca_verifier_ops, .reg =3D bpf_tcp_ca_reg, .unreg =3D bpf_tcp_ca_unreg, + .update =3D bpf_tcp_ca_update, .check_member =3D bpf_tcp_ca_check_member, .init_member =3D bpf_tcp_ca_init_member, .init =3D bpf_tcp_ca_init, diff --git a/net/ipv4/tcp_cong.c b/net/ipv4/tcp_cong.c index db8b4b488c31..981501871609 100644 --- a/net/ipv4/tcp_cong.c +++ b/net/ipv4/tcp_cong.c @@ -75,14 +75,8 @@ struct tcp_congestion_ops *tcp_ca_find_key(u32 key) return NULL; } =20 -/* - * Attach new congestion control algorithm to the list - * of available options. - */ -int tcp_register_congestion_control(struct tcp_congestion_ops *ca) +static int tcp_ca_validate(struct tcp_congestion_ops *ca) { - int ret =3D 0; - /* all algorithms must implement these */ if (!ca->ssthresh || !ca->undo_cwnd || !(ca->cong_avoid || ca->cong_control)) { @@ -90,6 +84,20 @@ int tcp_register_congestion_control(struct tcp_congest= ion_ops *ca) return -EINVAL; } =20 + return 0; +} + +/* Attach new congestion control algorithm to the list + * of available options. + */ +int tcp_register_congestion_control(struct tcp_congestion_ops *ca) +{ + int ret; + + ret =3D tcp_ca_validate(ca); + if (ret) + return ret; + ca->key =3D jhash(ca->name, sizeof(ca->name), strlen(ca->name)); =20 spin_lock(&tcp_cong_list_lock); @@ -130,6 +138,41 @@ void tcp_unregister_congestion_control(struct tcp_co= ngestion_ops *ca) } EXPORT_SYMBOL_GPL(tcp_unregister_congestion_control); =20 +/* Replace a registered old ca with a new one. + * + * The new ca must have the same name as the old one, that has been + * registered. + */ +int tcp_update_congestion_control(struct tcp_congestion_ops *ca, struct = tcp_congestion_ops *old_ca) +{ + struct tcp_congestion_ops *existing; + int ret; + + ret =3D tcp_ca_validate(ca); + if (ret) + return ret; + + ca->key =3D jhash(ca->name, sizeof(ca->name), strlen(ca->name)); + + spin_lock(&tcp_cong_list_lock); + existing =3D tcp_ca_find_key(old_ca->key); + if (ca->key =3D=3D TCP_CA_UNSPEC || !existing || strcmp(existing->name,= ca->name)) { + pr_notice("%s not registered or non-unique key\n", + ca->name); + ret =3D -EINVAL; + } else if (existing !=3D old_ca) { + pr_notice("invalid old congestion control algorithm to replace\n"); + ret =3D -EINVAL; + } else { + list_add_tail_rcu(&ca->list, &tcp_cong_list); + list_del_rcu(&existing->list); + pr_debug("%s updated\n", ca->name); + } + spin_unlock(&tcp_cong_list_lock); + + return ret; +} + u32 tcp_ca_get_key_by_name(struct net *net, const char *name, bool *ecn_= ca) { const struct tcp_congestion_ops *ca; --=20 2.30.2