From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f169.google.com (mail-il1-f169.google.com [209.85.166.169]) (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 5394E11717; Sun, 7 Jan 2024 21:13:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="A35VX3Rq" Received: by mail-il1-f169.google.com with SMTP id e9e14a558f8ab-35d374bebe3so653805ab.1; Sun, 07 Jan 2024 13:13:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1704662025; x=1705266825; darn=vger.kernel.org; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=ROm8ZhdgnvaZAIzOUEljUQj8Jiy9j8p4bOwcYNGDP80=; b=A35VX3RqUie08OvMzEkC+M1IuXrjLrn5UMU0YqwG90LXGtMezD4/b/GncgYh2KY4+R 6A7NOw55uQsVgw8ZdmrhudN5Z4sKBx5KyW6aqyHll+STGh21oeS9UxdWI74cil5psOrF lxv7wmyNrhxcyW0b4dXDFtpgM6xySUNYTWJV3r8dcVhdrCorPQuKZIV/UEZ2E1zaC/Tz 9ADPPpMuHE5JQ9MaGLJO3nxY9hFHE+xXCsuBdYrNwSct6D/uWfTcG4LParsJUvNAGwZE A1TawopeKvaJQiius44SQZykT9OKVpIc1eHLQxGXAyOoB3alhyDXFk1Z6GJyCJ7NljlB iZjA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1704662025; x=1705266825; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ROm8ZhdgnvaZAIzOUEljUQj8Jiy9j8p4bOwcYNGDP80=; b=wA32A4XhtlHv0H4v8gPoi9jWqtFGyhXMfjvg4igzk5wl4OzbSsmdXccgwaS/Vjjwdx Wu1KQFopp+Yn2vpLjruzxTVC55sJwUMK82EZQARxvYhuFe+8Q57mq5iYVVGj6YZQsIuv dsYsFFhZ4ysP0RHeiySCKDK87qJpalLElw+vYiBGLibA/d0mynzcxgL1Py6qCm1BFVI5 +8LkVGlVIBHAJVrSYAg7FvgcmNSLrKGc+tlSUbpNoKMCqOGIB2UdGwpcQEYdE2mB37di zAfTOa4nywthff6HRkwp1EDu6UfZIrp8E4dQaYdvWzkrspJQuqzQZXSsh59eym/QlnMu lFwg== X-Gm-Message-State: AOJu0YwIpscsJ54RBUH5dbYzLi7I/2zTt/WBFPurfxu2iC/l9bBNPtEf NfWks5wCxDKjARxiWfsYIc8= X-Google-Smtp-Source: AGHT+IF21MDjYIhNQdLPmFTxpaATVZGV9Y8IQG5WrfQGQEJn4TylQlOxYoMmqAaleCl1nqKkReo4Pg== X-Received: by 2002:a92:c54c:0:b0:35f:d4dc:1b1c with SMTP id a12-20020a92c54c000000b0035fd4dc1b1cmr4900291ilj.0.1704662025330; Sun, 07 Jan 2024 13:13:45 -0800 (PST) Received: from hoboy.vegasvil.org ([2600:1700:2430:6f6f:e2d5:5eff:fea5:802f]) by smtp.gmail.com with ESMTPSA id u187-20020a0dd2c4000000b005cb7fccffe2sm2614064ywd.126.2024.01.07.13.13.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 07 Jan 2024 13:13:44 -0800 (PST) Date: Sun, 7 Jan 2024 13:13:42 -0800 From: Richard Cochran To: Mahesh Bandewar =?utf-8?B?KOCkruCkueClh+CktiDgpKzgpILgpKHgpYfgpLXgpL4=?= =?utf-8?B?4KSwKQ==?= Cc: Netdev , Linux , David Miller , Jakub Kicinski , Eric Dumazet , Paolo Abeni , Jonathan Corbet , John Stultz , Don Hatchett , Yuliang Li , Mahesh Bandewar , Willem de Bruijn Subject: Re: [PATCHv3 net-next 2/3] ptp: add ioctl interface for ptp_gettimex64any() Message-ID: References: <20240104212439.3276458-1-maheshb@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Sat, Jan 06, 2024 at 12:08:57AM -0800, Mahesh Bandewar (महेश बंडेवार) wrote: > I disagree! NICs inherently benefit from bundled PTP devices due to > their superior low-latency, low-overhead, and precise TX/RX > timestamping capabilities. For demanding systems requiring increased > capacity, multiple NICs from various vendors are often deployed. > However, disciplining these diverse PTP devices across the host > demands a flexible approach; a general purpose syscall is not an > answer. The current PHC implementation using ioctls through exported > ptp devices (/dev/ptpX) provides a solid foundation that is per device > (/per NIC). > > This series is providing another piece in an existing suite of methods > used for disciplining / precision tuning (along with adjfine, adjtime, > gettime etc.) This addition is to take that precision even further. This reads like marketing fluff. You fail to provide any *technical* reason why your proposed cross time stamp method can only work with a new ioctl, and not as the back end of a system call. Thanks, Richard