From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-180.mta1.migadu.com (out-180.mta1.migadu.com [95.215.58.180]) (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 95466179A7 for ; Thu, 20 Feb 2025 23:02:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740092572; cv=none; b=YDXuuVQvLfI4hNrCPlPWd+ERGq5zeqoR2pmWBKvRh+GQJx7bA4liTLtmMrKZWFnmP2eIhm0bC6cuj3JMa1y1ykOyLwjsnSRExxt82qld2KXnQf0hlmBN412q783uiFB4HxH8ywXQ7HBYiGB819MDP2IOefWwijpDIWYEhh0f+kM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740092572; c=relaxed/simple; bh=uIaVptdvr0a2z/TZwEzCoqF9O1XeyQPSwljljV4KEUo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=PyftCdl7+NPHG49hfc+SNePJWDZfVwPaSXPQhC2Zes9zXaDh8xgCXgacGU0Lei0exF1UrEFqaSSw36/dJR9sV33h0ie3zAzdGgthCYBl84UWgGiDHzzvpu/SGVuxhYmaXZAwYsoi1FPjLvAYvXnWAh6/y68nZjPE2DFxdK2j8/U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=vS1t529t; arc=none smtp.client-ip=95.215.58.180 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="vS1t529t" Message-ID: <04bfac2e-e28d-45eb-a715-59ac4b58aca8@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1740092568; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/Eu8pMeDIWiKwVDhxOuwqXCLJhjCur03nD0DkknqcV4=; b=vS1t529tZKZ0RVfPV34OM2ab9Z/C/GYc2cnXMDl7QjatidUR/luDmlrGsM3LBgbbV9nsdj McIk/Erc3cnT8z+jLTzYBe65foflrxUu9F/lC4SC0rUnEKGae4ypjvztifKaBZyqxrfju/ a67HouTb1fGHwe1rCfJ6cf+bpiW03cE= Date: Thu, 20 Feb 2025 15:02:41 -0800 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH bpf-next v13 00/12] net-timestamp: bpf extension to equip applications transparently To: Jason Xing , Willem de Bruijn Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, dsahern@kernel.org, willemb@google.com, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, song@kernel.org, yonghong.song@linux.dev, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@fomichev.me, haoluo@google.com, jolsa@kernel.org, shuah@kernel.org, ykolal@fb.com, bpf@vger.kernel.org, netdev@vger.kernel.org References: <20250220072940.99994-1-kerneljasonxing@gmail.com> <67b74b0ca099e_261ab62945f@willemb.c.googlers.com.notmuch> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Martin KaFai Lau In-Reply-To: <67b74b0ca099e_261ab62945f@willemb.c.googlers.com.notmuch> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 2/20/25 7:32 AM, Willem de Bruijn wrote: > Jason Xing wrote: >> "Timestamping is key to debugging network stack latency. With >> SO_TIMESTAMPING, bugs that are otherwise incorrectly assumed to be >> network issues can be attributed to the kernel." This is extracted >> from the talk "SO_TIMESTAMPING: Powering Fleetwide RPC Monitoring" >> addressed by Willem de Bruijn at netdevconf 0x17). >> >> There are a few areas that need optimization with the consideration of >> easier use and less performance impact, which I highlighted and mainly >> discussed at netconf 2024 with Willem de Bruijn and John Fastabend: >> uAPI compatibility, extra system call overhead, and the need for >> application modification. I initially managed to solve these issues >> by writing a kernel module that hooks various key functions. However, >> this approach is not suitable for the next kernel release. Therefore, >> a BPF extension was proposed. During recent period, Martin KaFai Lau >> provides invaluable suggestions about BPF along the way. Many thanks >> here! >> >> This series adds the BPF networking timestamping infrastructure through >> reusing most of the tx timestamping callback that is currently enabled >> by the SO_TIMESTAMPING.. This series also adds TX timestamping support >> for TCP. The RX timestamping and UDP support will be added in the future. Thanks for working on this BPF feature. Applied. > This series addresses all my feedback. > > The timestamping patches all have my Reviewed-by. Thanks to Willem and other reviewers for their input in this long thread across many revisions.