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=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 506AFC07E95 for ; Mon, 19 Jul 2021 16:51:57 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B153C60FE9 for ; Mon, 19 Jul 2021 16:51:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B153C60FE9 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 ([::1]:52386 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m5WUl-0006Uy-S5 for qemu-devel@archiver.kernel.org; Mon, 19 Jul 2021 12:51:55 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:37156) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m5WTb-0005jE-C2 for qemu-devel@nongnu.org; Mon, 19 Jul 2021 12:50:43 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:57892) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m5WTX-0004Ta-D2 for qemu-devel@nongnu.org; Mon, 19 Jul 2021 12:50:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1626713438; h=from:from:reply-to: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=on/OH3d2gic4o1UamyJw7lNqSpSfjOaFSZpcr/CuODI=; b=ej1T59f+yR+BfWGJc7GxD4UQ2vnlXYgJFjC9wmWcIslq9d2/fRD9uU/D6+XKBvtZL7LWVt m+M+MZxnTsBTiPUGQ0G1i+2+EfyIG0sSW54WpC2DV7QRh8jE5Zq9dDUjVsvrcO8rYA/z4l zC+dRZACC8dWGtbKmEVnF9A5EnoyfUk= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-362-BTFUFy6dP4K5T2bBfsdv9A-1; Mon, 19 Jul 2021 12:50:37 -0400 X-MC-Unique: BTFUFy6dP4K5T2bBfsdv9A-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 147E1100C610; Mon, 19 Jul 2021 16:50:34 +0000 (UTC) Received: from redhat.com (ovpn-112-193.ams2.redhat.com [10.36.112.193]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 72B595D9F0; Mon, 19 Jul 2021 16:50:26 +0000 (UTC) Date: Mon, 19 Jul 2021 17:50:23 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Andrew Jones Subject: Re: [PATCH for-6.2 v2 02/11] machine: Make smp_parse generic enough for all arches Message-ID: References: <20210719032043.25416-1-wangyanan55@huawei.com> <20210719032043.25416-3-wangyanan55@huawei.com> <20210719162846.dcltg22pbdpnyjcl@gator> <20210719164815.bzfnrk6fzhfj5quj@gator> MIME-Version: 1.0 In-Reply-To: <20210719164815.bzfnrk6fzhfj5quj@gator> User-Agent: Mutt/2.0.7 (2021-05-04) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -42 X-Spam_score: -4.3 X-Spam_bar: ---- X-Spam_report: (-4.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.469, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Peter Maydell , Thomas Huth , Eduardo Habkost , "Michael S . Tsirkin" , wanghaibin.wang@huawei.com, Richard Henderson , qemu-devel@nongnu.org, Greg Kurz , Yanan Wang , yuzenghui@huawei.com, Igor Mammedov , Halil Pasic , Paolo Bonzini , David Gibson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Jul 19, 2021 at 06:48:15PM +0200, Andrew Jones wrote: > On Mon, Jul 19, 2021 at 05:36:39PM +0100, Daniel P. Berrangé wrote: > > On Mon, Jul 19, 2021 at 06:28:46PM +0200, Andrew Jones wrote: > > > On Mon, Jul 19, 2021 at 11:20:34AM +0800, Yanan Wang wrote: > > > > Currently the only difference between smp_parse and pc_smp_parse > > > > is the support of multi-dies and the related error reporting code. > > > > With an arch compat variable "bool smp_dies_supported", we can > > > > easily make smp_parse generic enough for all arches and the PC > > > > specific one can be removed. > > > > > > > > Making smp_parse() generic enough can reduce code duplication and > > > > ease the code maintenance, and also allows extending the topology > > > > with more arch specific members (e.g., clusters) in the future. > > > > > > > > No functional change intended. > > > > > > > > Suggested-by: Andrew Jones > > > > Signed-off-by: Yanan Wang > > > > --- > > > > hw/core/machine.c | 28 ++++++++++------- > > > > hw/i386/pc.c | 76 +-------------------------------------------- > > > > include/hw/boards.h | 1 + > > > > 3 files changed, 19 insertions(+), 86 deletions(-) > > > > > > > > diff --git a/hw/core/machine.c b/hw/core/machine.c > > > > index d73daa10f4..ed6712e964 100644 > > > > --- a/hw/core/machine.c > > > > +++ b/hw/core/machine.c > > > > @@ -743,6 +743,7 @@ void machine_set_cpu_numa_node(MachineState *machine, > > > > > > > > static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp) > > > > { > > > > + MachineClass *mc = MACHINE_GET_CLASS(ms); > > > > unsigned cpus = config->has_cpus ? config->cpus : 0; > > > > unsigned sockets = config->has_sockets ? config->sockets : 0; > > > > unsigned dies = config->has_dies ? config->dies : 1; > > > > @@ -761,7 +762,7 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp) > > > > return; > > > > } > > > > > > > > - if (dies > 1) { > > > > + if (!mc->smp_dies_supported && dies > 1) { > > > > > > Won't this allow a user on an arch with !mc->smp_dies_supported to specify > > > dies=1? > > > > Conceptually that is fine. Before the introduction of CPU sockets > > with 2+ dies, you can credibly say that all sockets had 1 die, so > > it is nreasonable for users to say -smp ....,dies=1,.... > > > > libvirt will unconditionally set dies=1 for all QEMU targets if > > the user didn't specify an explicit dies value > > > > > To not allow that, can we do > > > > > > if (!mc->smp_dies_supported && config->has_dies) > > > > > > instead? > > > > I don't see that this is benefitting apps/users. > > Other than maintaining consistency; erroring with "we don't support dies" > for 2+, but not for 1, is inconsistent, then I agree there isn't much > reason to disallow it, since we'll be using the value of 1 anyway > internally. I don't really have a strong preference here, so I'm fine with > allowing dies=1. How about we tweak the error message from "dies not supported by this machine's CPU topology" to "multiple dies not supported by this machine's CPU topology" Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|