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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 38534C04AB5 for ; Thu, 6 Jun 2019 16:52:17 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0E10920693 for ; Thu, 6 Jun 2019 16:52:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0E10920693 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:35246 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hYvcd-0000qM-KI for qemu-devel@archiver.kernel.org; Thu, 06 Jun 2019 12:52:15 -0400 Received: from eggs.gnu.org ([209.51.188.92]:60369) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hYvbU-0008U5-3k for qemu-devel@nongnu.org; Thu, 06 Jun 2019 12:51:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hYvbS-0003eL-1N for qemu-devel@nongnu.org; Thu, 06 Jun 2019 12:51:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:19664) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hYvbQ-0003VA-5C for qemu-devel@nongnu.org; Thu, 06 Jun 2019 12:51:01 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 35C0930C31A7; Thu, 6 Jun 2019 16:50:50 +0000 (UTC) Received: from localhost (unknown [10.43.2.182]) by smtp.corp.redhat.com (Postfix) with ESMTP id 10F182B587; Thu, 6 Jun 2019 16:50:44 +0000 (UTC) Date: Thu, 6 Jun 2019 18:50:40 +0200 From: Igor Mammedov To: Eric Blake Message-ID: <20190606185040.7eb6c32e@redhat.com> In-Reply-To: References: <20190508061726.27631-1-tao3.xu@intel.com> <20190508061726.27631-9-tao3.xu@intel.com> <20190605164045.12bf194c@redhat.com> <58e8adc3-18f1-04a6-2c92-baa234293a6f@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Thu, 06 Jun 2019 16:50:57 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH v4 08/11] numa: Extend the command-line to provide memory latency and bandwidth information X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: xiaoguangrong.eric@gmail.com, mst@redhat.com, jingqi.liu@intel.com, Tao Xu , qemu-devel@nongnu.org, Markus Armbruster , pbonzini@redhat.com, rth@twiddle.net, ehabkost@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, 6 Jun 2019 08:23:47 -0500 Eric Blake wrote: > On 6/6/19 2:47 AM, Tao Xu wrote: > > On 6/5/2019 10:40 PM, Igor Mammedov wrote: =20 > >> On Wed,=C2=A0 8 May 2019 14:17:23 +0800 > >> Tao Xu wrote: > >> =20 > >>> From: Liu Jingqi > >>> > >>> Add -numa hmat-lb option to provide System Locality Latency and > >>> Bandwidth Information. These memory attributes help to build > >>> System Locality Latency and Bandwidth Information Structure(s) > >>> in ACPI Heterogeneous Memory Attribute Table (HMAT). > >>> > >>> Signed-off-by: Liu Jingqi > >>> Signed-off-by: Tao Xu > >>> --- =20 > > ... =20 > >>> +## > >>> +{ 'struct': 'NumaHmatLBOptions', > >>> +=C2=A0 'data': { > >>> +=C2=A0=C2=A0 'initiator': 'uint16', > >>> +=C2=A0=C2=A0 'target': 'uint16', > >>> +=C2=A0=C2=A0 'hierarchy': 'HmatLBMemoryHierarchy', > >>> +=C2=A0=C2=A0 'data-type': 'HmatLBDataType', =20 > >> I think union will be better here with data-type used as discriminator, > >> on top of that you'll be able to drop a bit of error checking above si= nce > >> QAPI's union will not allow user to mix latency and bandwidth. > >> =20 > > Hi Igor, > >=20 > > I have quesion here, the 'hmat-lb' is a member of a union 'NumaOptions', > > it seems can' use a union as a member of union. =20 >=20 > It should be technically possible to expand the QAPI generators to allow > one union as a branch within another union, so long as there are no > collisions in identifiers, if that makes for the smartest on-the-wire > representation. It would save quite a bit of boiler plate error checking in numa code, but since I don't know much about QAPI to make meaningful suggestion how to implement it, I won't insist on using union.