From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) (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 4ED7B1C84A0; Sun, 14 Dec 2025 11:36:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.97.179.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765712170; cv=none; b=o/H11Xm0ZCKc3drCtHsqmEieG4pqpqBWbrKMm583u7CqNszb1WbDj+wrrhbxzZNiTvuYDX34mU7zVndsgjobEKJB/pgwyAZ+g/N3OwFdpqU4P6nviIbGBeO0Kt7wHu7PoQsGFAeu+T11P1hn8WXt+IIPWhsv9fi4L2EEJGEsKhk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765712170; c=relaxed/simple; bh=aY/8hLQczdtZhqoQy3HUv8F39g3UqechMQ6sT1nsuVY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=p7thr41SGE+TAzb5rCYwiiMXiWk5+ZZojLYx/x9GbJUWjEnnkeD90T0AIFXWT+/p0oRXjlu4n1lJeW4m6WJZMRddXUzVcoX7UGw4hvgThY5wNKCMmSdu0xGbEOkUx6FvyxvzKshzGFFDUMTaAzwJBQiNIaIwHEmjlGUpBCqgjDQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com; spf=pass smtp.mailfrom=igalia.com; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b=bUF5wS0H; arc=none smtp.client-ip=213.97.179.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=igalia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b="bUF5wS0H" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:From: References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=2AWI8+vsS10/WL/nLrVrHfW4flPvgf4fAkFASYswKN4=; b=bUF5wS0HF7Zuu67arKGsHLgzGV zLiG/LjGhbTBfxMKlQLh+OYevQNn4/FGUng1h0ChebDzAfDxVSMkq+ODcD3B/co/UL4u9ZtWo15kB +cNsdodikqNJ3BHQwWg9Gv4P4njM93KT5rLH8Pr1gibTs9PqLyWqukEDLuRW3wDP8NTOnuWOAv5H9 Ia5JX4VG/Ny+rsExDkMaC5emfzyGB1hPK63iS2HgIMjqSzXjhnTgVUSNgvZbMmeDInfGf2k17tTyl A2Hmmu1Xh6v6kB749xOtq0BMCoUCY/7Rdhc4vmIBNr937oS8CUkFyEn35AFIDBLpoK+NEhE7UM7mt +R+V5Pkg==; Received: from [58.29.143.236] (helo=[192.168.1.6]) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_128_GCM:128) (Exim) id 1vUkOP-00CbUO-KT; Sun, 14 Dec 2025 12:36:02 +0100 Message-ID: <4bb1ea43-ef52-47ae-8009-6a2944dbf92b@igalia.com> Date: Sun, 14 Dec 2025 20:35:54 +0900 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Concerns with em.yaml YNL spec To: Andrew Lunn , Donald Hunter Cc: Lukasz Luba , linux-pm@vger.kernel.org, sched-ext@lists.linux.dev, Jakub Kicinski , Network Development , Linux Kernel Mailing List References: <081e0ba7-055c-4243-8b39-e2c0cb9a8c5a@lunn.ch> From: Changwoo Min Content-Language: en-US, ko-KR, en-US-large, ko In-Reply-To: <081e0ba7-055c-4243-8b39-e2c0cb9a8c5a@lunn.ch> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 12/12/25 02:01, Andrew Lunn wrote: > On Thu, Dec 11, 2025 at 03:54:53PM +0000, Donald Hunter wrote: >> Hi, >> >> I just spotted the new em.yaml YNL spec that got merged in >> bd26631ccdfd ("PM: EM: Add em.yaml and autogen files") as part of [1] >> because it introduced new yamllint reports: >> >> make -C tools/net/ynl/ lint >> make: Entering directory '/home/donaldh/net-next/tools/net/ynl' >> yamllint ../../../Documentation/netlink/specs >> ../../../Documentation/netlink/specs/em.yaml >> 3:1 warning missing document start "---" (document-start) >> 107:13 error wrong indentation: expected 10 but found 12 (indentation) >> >> I guess the patch series was never cced to netdev or the YNL >> maintainers so this is my first opportunity to review it. >> >> Other than the lint messages, there are a few concerns with the >> content of the spec: >> >> - pds, pd and ps might be meaningful to energy model experts but they >> are pretty meaningless to the rest of us. I see they are spelled out >> in the energy model header file so it would be better to use >> perf-domain, perf-table and perf-state here. > > We also need to watch out for other meaning of these letters. In the > context of networking and Power over Ethernet, PD means Powered > Device. We generally don't need to enumerate the PD, we are more > interested in the Power Sourcing Equipment, PSE. > > And a dumb question. What is an energy model? A PSE needs some level > of energy model, it needs to know how much energy each PD can consume > in order that it is not oversubscribed.Is the energy model generic > enough that it could be used for this? Or should this energy model get > a prefix to limit its scope to a performance domain? The suggested > name of this file would then become something like > performance-domain-energy-model.yml? > Lukasz might be the right person for this question. In my view, the energy model essentially provides the performance-versus-power- consumption curve for each performance domain. Conceptually, the energy model covers the system-wide information; a performance domain is information about one domain (e.g., big/medium/ little CPU blocks), so it is under the energy model; a performance state is one dot in the performance-versus-power-consumption curve of a performance domain. Since the energy model covers the system-wide information, energy- model.yaml (as Donald suggested) sounds better to me. Regards, Changwoo Min