From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ua1-f73.google.com (mail-ua1-f73.google.com [209.85.222.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 79FA738C2B5 for ; Thu, 16 Apr 2026 20:03:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776369813; cv=none; b=h0VPhE8MP1fzBM+DVOa26hvOs6T8HI0AP1uqY/uS3z0rXDkwNkbGUuQ34irzXel2Xw0GaXmv6X5u8bgAvz6yZntTFnx8h28ytNY2JZBzB3yC3lB3j79PTsLZO7/8DOXItrKKY1pTaO5E+pVJYUmq2tlLBLkXT4Htvc9GEvjuDbs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776369813; c=relaxed/simple; bh=vIkWRDzo3EDvTR6bAlqkznEDh5KFydinAo8Siy8tpRw=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=pzgcR44ZivKaIjq9l2zixrHAzfBa1/eHoIME+vWWzrI5dyKuTSUKZKoBNhSKvLYC8mOXGBQRjrjyGZ+CE8ZFNRgZKj+nUtgEsLdvI7HieQkm0IrTXYWkeINR4EXMFhJ/y6k0m3pe6qWQkGhOSWkR4bpUeye/d6NEtQDbGRWT0AI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=CxiXrQDQ; arc=none smtp.client-ip=209.85.222.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CxiXrQDQ" Received: by mail-ua1-f73.google.com with SMTP id a1e0cc1a2514c-956995b87e6so6936190241.3 for ; Thu, 16 Apr 2026 13:03:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1776369804; x=1776974604; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=opNwWZN1co7vlxK7a/fMpwUn0yhkKvANh3SI5hyTq7A=; b=CxiXrQDQntlZTdySO6unylooO2mnOPgm/rZ5pU5zDJU/4O+nutxs4TvXokKsZQKefN sbQhd6tYXITF3C91gDccdflBhlWa5WxMwEd4AWEO8HKGUw8S04tjSrrghFRq6uwZsSx4 EhVW1qIBGqNX7H+xhb8keFup1q5udFwkxGvHzbyuiDBH3yVMwOv+X84UisVzUhB6twRb fVwcQHRw4eMv8VVwfYwUfHHMbF+T70/UoztVB/6JFag2lzbA73wxGcMoZCjSKbOH6GmH 2n5kQsgJKgSOwtJPd8aSQ6lbj2iIvLeFG3HkK8kYhIMEnY00r7tu4pEO0QvDFgcqgtGc 9sVQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776369804; x=1776974604; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=opNwWZN1co7vlxK7a/fMpwUn0yhkKvANh3SI5hyTq7A=; b=tYN53WkD22hqGYGYDub74tEBNyXPocCP9XiQIVvw/ArYJ3topEXIo8mvuHlFllNjwE 91TWOig1WnXpjgGny9nGSIfyCvT9HUkm+7yuJ6ZLwqahmwcvkrsafr7XiYdf/LESV9ay uKo0AT0Bs2PABIv43Ue0S6nhN4iaDP7r9Y9BxlROCpSfXeTmZNudkQ9nEy4Zna53Leu/ uI0qyIBdcU/H3axatw9jzwELS11ayBWaiUINDfbt/5GFvWge6dRUggRAzM2OP/lvYFLz Jii2A5gI6iT562+zHRPDRjmhiRMNNVR/2nywEFNqoafyRao/q2pRTJlHhgfRc6DiGLEz nq7g== X-Forwarded-Encrypted: i=1; AFNElJ8XCZ1zrfjX79yHzO6XqJpvCNp6WGhpt+muFtp6P5gymVI/aaaIBXh6IvBstQHyOAa8TMwOGnE=@vger.kernel.org X-Gm-Message-State: AOJu0YxnGDQZh0uPRF8CNZCwkkyTkuFzPccQnhc3IPevSZPlV1+Gr4Wn fPs4ulWQqhXr+tUKCsFKCDYr9KkAU/lt8b9sE1RA/bfKI933wFsk/blaoaT1vQmiI0b76mC1xey uzHHoEFUXdooueQ== X-Received: from qvxa1.prod.google.com ([2002:a05:6214:621:b0:89c:c936:5ac9]) (user=edumazet job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6102:3749:b0:606:49d:1861 with SMTP id ada2fe7eead31-616ce4784dcmr349080137.27.1776369804121; Thu, 16 Apr 2026 13:03:24 -0700 (PDT) Date: Thu, 16 Apr 2026 20:03:07 +0000 In-Reply-To: <20260416200319.3608680-1-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260416200319.3608680-1-edumazet@google.com> X-Mailer: git-send-email 2.54.0.rc1.513.gad8abe7a5a-goog Message-ID: <20260416200319.3608680-3-edumazet@google.com> Subject: [PATCH net 02/14] tcp: add data-race annotations around tp->data_segs_out and tp->total_retrans From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , Neal Cardwell , Kuniyuki Iwashima , netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet Content-Type: text/plain; charset="UTF-8" tcp_get_timestamping_opt_stats() intentionally runs lockless, we must add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy. Fixes: 7e98102f4897 ("tcp: record pkts sent and retransmistted") Signed-off-by: Eric Dumazet --- net/ipv4/tcp.c | 4 ++-- net/ipv4/tcp_output.c | 8 +++++--- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 7b7812cb710f6e05a83615811eefd0cf8a845cab..e39e0734d958f39aa83a33f5c608ce3b94232fb1 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4434,9 +4434,9 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk, nla_put_u64_64bit(stats, TCP_NLA_SNDBUF_LIMITED, info.tcpi_sndbuf_limited, TCP_NLA_PAD); nla_put_u64_64bit(stats, TCP_NLA_DATA_SEGS_OUT, - tp->data_segs_out, TCP_NLA_PAD); + READ_ONCE(tp->data_segs_out), TCP_NLA_PAD); nla_put_u64_64bit(stats, TCP_NLA_TOTAL_RETRANS, - tp->total_retrans, TCP_NLA_PAD); + READ_ONCE(tp->total_retrans), TCP_NLA_PAD); rate = READ_ONCE(sk->sk_pacing_rate); rate64 = (rate != ~0UL) ? rate : ~0ULL; diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 8e99687526a64cef0c8f7b8f0d5ec7a5fa883f09..d8e8bba2d03a3be5e7a9ebac16e39f4a29ae6037 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1688,7 +1688,8 @@ static int __tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, if (skb->len != tcp_header_size) { tcp_event_data_sent(tp, sk); - tp->data_segs_out += tcp_skb_pcount(skb); + WRITE_ONCE(tp->data_segs_out, + tp->data_segs_out + tcp_skb_pcount(skb)); tp->bytes_sent += skb->len - tcp_header_size; } @@ -3642,7 +3643,7 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs) TCP_ADD_STATS(sock_net(sk), TCP_MIB_RETRANSSEGS, segs); if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN) __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSYNRETRANS); - tp->total_retrans += segs; + WRITE_ONCE(tp->total_retrans, tp->total_retrans + segs); tp->bytes_retrans += skb->len; /* make sure skb->data is aligned on arches that require it @@ -4646,7 +4647,8 @@ int tcp_rtx_synack(const struct sock *sk, struct request_sock *req) * However in this case, we are dealing with a passive fastopen * socket thus we can change total_retrans value. */ - tcp_sk_rw(sk)->total_retrans++; + WRITE_ONCE(tcp_sk_rw(sk)->total_retrans, + tcp_sk_rw(sk)->total_retrans + 1); } trace_tcp_retransmit_synack(sk, req); WRITE_ONCE(req->num_retrans, req->num_retrans + 1); -- 2.54.0.rc1.513.gad8abe7a5a-goog