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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 450E6C3F2D1 for ; Wed, 4 Mar 2020 10:14:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1F02420848 for ; Wed, 4 Mar 2020 10:14:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=cloudflare.com header.i=@cloudflare.com header.b="q2ophHX5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388010AbgCDKOe (ORCPT ); Wed, 4 Mar 2020 05:14:34 -0500 Received: from mail-lf1-f66.google.com ([209.85.167.66]:39161 "EHLO mail-lf1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728946AbgCDKNl (ORCPT ); Wed, 4 Mar 2020 05:13:41 -0500 Received: by mail-lf1-f66.google.com with SMTP id n30so1017848lfh.6 for ; Wed, 04 Mar 2020 02:13:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloudflare.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=WcIJ9lCZ97FXYirMRy6aCjRDlIzgj0wNvh43wB0M0DM=; b=q2ophHX5EW/6f77pOSGjfwqstKPYYFPktGOeNJbubRG0sfZQD+z5bDrME56aNqyBmH hcSuI3wctqMT4PzPXjaAOgeavEWUsTqSypIow6YYY8x3eKBLhGpGJU8nZFWCfsqv4nlg 646DypBctCYqT5DueCkyVr3/6mc9Xmd6mL0Dw= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=WcIJ9lCZ97FXYirMRy6aCjRDlIzgj0wNvh43wB0M0DM=; b=rjareZdIkkqmvUA+kdU7qk4fN05OCH6Ho7S5UsArsISfF/TccnKMFFVsiut0dorQTr gqglFoCsqW1QyeCPo+ZxEKQljSa6AYyjUPE7x+kjHJ91cQyKEKXkb96hwGZekMfM0Ubu pn90Bj1bf51WsGi5TpstE6m3oejzMmBcWihgidJNbNAeCw5ThWvosi02o+bdcuLRTspW kgRcug+dUI0hhmNlZw2X+yQdUlHCI57D2pAdfJEh/U2qJZzsWguh515zcO7qhpk+1iRN xsrYek2tVsp/cW0L923oh/2uEKsn8j6s62lmqXpFTtr0F8YBkjK/ENG3b8hQHt8Rdy2A Yy1A== X-Gm-Message-State: ANhLgQ0ALz1s4te6uDvt+6FaX76n4WfGolmwyHtEDxnw3OXaKSBRC/4c 343xfdeqSOiMrRG5olavo5u7IQ== X-Google-Smtp-Source: ADFU+vs/CTV/qo8RUQFXEsrJ/JkI3oT0QA0rJ1qLhtmshs+jh7HdlgfS2Yqr2gnhT3u+9ckrBuotJQ== X-Received: by 2002:a19:c515:: with SMTP id w21mr1579786lfe.169.1583316819485; Wed, 04 Mar 2020 02:13:39 -0800 (PST) Received: from localhost.localdomain ([176.221.114.230]) by smtp.gmail.com with ESMTPSA id l7sm341777lfk.65.2020.03.04.02.13.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 Mar 2020 02:13:38 -0800 (PST) From: Lorenz Bauer To: john.fastabend@gmail.com, Daniel Borkmann , Jakub Sitnicki , Lorenz Bauer , Eric Dumazet , "David S. Miller" , Alexey Kuznetsov , Hideaki YOSHIFUJI , Jakub Kicinski , Alexei Starovoitov Cc: kernel-team@cloudflare.com, netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH bpf-next v3 02/12] skmsg: update saved hooks only once Date: Wed, 4 Mar 2020 11:13:07 +0100 Message-Id: <20200304101318.5225-3-lmb@cloudflare.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200304101318.5225-1-lmb@cloudflare.com> References: <20200304101318.5225-1-lmb@cloudflare.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Only update psock->saved_* if psock->sk_proto has not been initialized yet. This allows us to get rid of tcp_bpf_reinit_sk_prot. Signed-off-by: Lorenz Bauer --- include/linux/skmsg.h | 20 ++++++++++++++++---- net/ipv4/tcp_bpf.c | 16 +--------------- 2 files changed, 17 insertions(+), 19 deletions(-) diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h index 4d3d75d63066..2be51b7a5800 100644 --- a/include/linux/skmsg.h +++ b/include/linux/skmsg.h @@ -347,11 +347,23 @@ static inline void sk_psock_update_proto(struct sock *sk, struct sk_psock *psock, struct proto *ops) { - psock->saved_unhash = sk->sk_prot->unhash; - psock->saved_close = sk->sk_prot->close; - psock->saved_write_space = sk->sk_write_space; + /* Initialize saved callbacks and original proto only once, since this + * function may be called multiple times for a psock, e.g. when + * psock->progs.msg_parser is updated. + * + * Since we've not installed the new proto, psock is not yet in use and + * we can initialize it without synchronization. + */ + if (!psock->sk_proto) { + struct proto *orig = READ_ONCE(sk->sk_prot); + + psock->saved_unhash = orig->unhash; + psock->saved_close = orig->close; + psock->saved_write_space = sk->sk_write_space; + + psock->sk_proto = orig; + } - psock->sk_proto = sk->sk_prot; /* Pairs with lockless read in sk_clone_lock() */ WRITE_ONCE(sk->sk_prot, ops); } diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c index 7d6e1b75d4d4..3327afa05c3d 100644 --- a/net/ipv4/tcp_bpf.c +++ b/net/ipv4/tcp_bpf.c @@ -637,20 +637,6 @@ static void tcp_bpf_update_sk_prot(struct sock *sk, struct sk_psock *psock) sk_psock_update_proto(sk, psock, &tcp_bpf_prots[family][config]); } -static void tcp_bpf_reinit_sk_prot(struct sock *sk, struct sk_psock *psock) -{ - int family = sk->sk_family == AF_INET6 ? TCP_BPF_IPV6 : TCP_BPF_IPV4; - int config = psock->progs.msg_parser ? TCP_BPF_TX : TCP_BPF_BASE; - - /* Reinit occurs when program types change e.g. TCP_BPF_TX is removed - * or added requiring sk_prot hook updates. We keep original saved - * hooks in this case. - * - * Pairs with lockless read in sk_clone_lock(). - */ - WRITE_ONCE(sk->sk_prot, &tcp_bpf_prots[family][config]); -} - static int tcp_bpf_assert_proto_ops(struct proto *ops) { /* In order to avoid retpoline, we make assumptions when we call @@ -670,7 +656,7 @@ void tcp_bpf_reinit(struct sock *sk) rcu_read_lock(); psock = sk_psock(sk); - tcp_bpf_reinit_sk_prot(sk, psock); + tcp_bpf_update_sk_prot(sk, psock); rcu_read_unlock(); } -- 2.20.1