From patchwork Fri Jul 23 09:57:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yanan Wang X-Patchwork-Id: 12395781 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 4703DC43216 for ; Fri, 23 Jul 2021 09:58:50 +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 B0F6160EC0 for ; Fri, 23 Jul 2021 09:58:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org B0F6160EC0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:58054 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m6rxA-00019M-F7 for qemu-devel@archiver.kernel.org; Fri, 23 Jul 2021 05:58:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:54100) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m6rwA-0008Gm-G0 for qemu-devel@nongnu.org; Fri, 23 Jul 2021 05:57:46 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:2446) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m6rw6-0000SP-Bq for qemu-devel@nongnu.org; Fri, 23 Jul 2021 05:57:46 -0400 Received: from dggemv703-chm.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4GWPmL5CVVzZrfc; Fri, 23 Jul 2021 17:54:10 +0800 (CST) Received: from dggpemm500023.china.huawei.com (7.185.36.83) by dggemv703-chm.china.huawei.com (10.3.19.46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Fri, 23 Jul 2021 17:57:35 +0800 Received: from DESKTOP-TMVL5KK.china.huawei.com (10.174.187.128) by dggpemm500023.china.huawei.com (7.185.36.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Fri, 23 Jul 2021 17:57:34 +0800 From: Yanan Wang To: Subject: [PATCH for-6.1 v5 1/1] machine: Disallow specifying topology parameters as zero Date: Fri, 23 Jul 2021 17:57:31 +0800 Message-ID: <20210723095731.4976-2-wangyanan55@huawei.com> X-Mailer: git-send-email 2.8.4.windows.1 In-Reply-To: <20210723095731.4976-1-wangyanan55@huawei.com> References: <20210723095731.4976-1-wangyanan55@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.187.128] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpemm500023.china.huawei.com (7.185.36.83) X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.187; envelope-from=wangyanan55@huawei.com; helo=szxga01-in.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, 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: , Cc: Peter Maydell , Andrew Jones , =?utf-8?q?Daniel_P_=2E_Berrang=C3=A9?= , Eduardo Habkost , Pierre Morel , Pankaj Gupta , wanghaibin.wang@huawei.com, Cornelia Huck , Markus Armbruster , Yanan Wang , Cleber Rosa , yuzenghui@huawei.com, Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" In the SMP configuration, we should either specify a topology parameter with a reasonable value (equal to or greater than 1) or just leave it omitted and QEMU will calculate its value. Configurations which explicitly specify the topology parameters as zero like "sockets=0" are meaningless, so disallow them. However, the commit 1e63fe685804d (machine: pass QAPI struct to mc->smp_parse) has documented that '0' has the same semantics as omitting a parameter in the qapi comment for SMPConfiguration. So this patch fixes the doc and also adds the corresponding sanity check. Reviewed-by: Cornelia Huck Reviewed-by: Andrew Jones Reviewed-by: Daniel P. Berrange Tested-by: Daniel P. Berrange Suggested-by: Andrew Jones Signed-off-by: Yanan Wang --- hw/core/machine.c | 14 ++++++++++++++ qapi/machine.json | 6 +++--- qemu-options.hx | 12 +++++++----- 3 files changed, 24 insertions(+), 8 deletions(-) diff --git a/hw/core/machine.c b/hw/core/machine.c index 775add0795..e1533dfc47 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -829,6 +829,20 @@ static void machine_set_smp(Object *obj, Visitor *v, const char *name, return; } + /* + * The CPU topology parameters must be specified greater than zero or + * just omitted, explicit configuration like "cpus=0" is not allowed. + */ + if ((config->has_cpus && config->cpus == 0) || + (config->has_sockets && config->sockets == 0) || + (config->has_dies && config->dies == 0) || + (config->has_cores && config->cores == 0) || + (config->has_threads && config->threads == 0) || + (config->has_maxcpus && config->maxcpus == 0)) { + error_setg(errp, "CPU topology parameters must be greater than zero"); + goto out_free; + } + mc->smp_parse(ms, config, errp); if (errp) { goto out_free; diff --git a/qapi/machine.json b/qapi/machine.json index c3210ee1fb..9272cb3cf8 100644 --- a/qapi/machine.json +++ b/qapi/machine.json @@ -1288,8 +1288,8 @@ ## # @SMPConfiguration: # -# Schema for CPU topology configuration. "0" or a missing value lets -# QEMU figure out a suitable value based on the ones that are provided. +# Schema for CPU topology configuration. A missing value lets QEMU +# figure out a suitable value based on the ones that are provided. # # @cpus: number of virtual CPUs in the virtual machine # @@ -1297,7 +1297,7 @@ # # @dies: number of dies per socket in the CPU topology # -# @cores: number of cores per thread in the CPU topology +# @cores: number of cores per die in the CPU topology # # @threads: number of threads per core in the CPU topology # diff --git a/qemu-options.hx b/qemu-options.hx index 99ed5ec5f1..e077aa80bf 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -223,11 +223,13 @@ SRST of computing the CPU maximum count. Either the initial CPU count, or at least one of the topology parameters - must be specified. Values for any omitted parameters will be computed - from those which are given. Historically preference was given to the - coarsest topology parameters when computing missing values (ie sockets - preferred over cores, which were preferred over threads), however, this - behaviour is considered liable to change. + must be specified. The specified parameters must be greater than zero, + explicit configuration like "cpus=0" is not allowed. Values for any + omitted parameters will be computed from those which are given. + Historically preference was given to the coarsest topology parameters + when computing missing values (ie sockets preferred over cores, which + were preferred over threads), however, this behaviour is considered + liable to change. ERST DEF("numa", HAS_ARG, QEMU_OPTION_numa,