From patchwork Thu Sep 2 11:03:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "wangyanan (Y)" X-Patchwork-Id: 1523628 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) 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 ozlabs.org (Postfix) with ESMTPS id 4H0dbQ0Bj2z9sW5 for ; Thu, 2 Sep 2021 21:13:54 +1000 (AEST) Received: from localhost ([::1]:44180 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mLkfH-00060J-N3 for incoming@patchwork.ozlabs.org; Thu, 02 Sep 2021 07:13:51 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43668) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mLkVd-00076t-Gq; Thu, 02 Sep 2021 07:03:53 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:3126) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mLkVW-0003dw-D6; Thu, 02 Sep 2021 07:03:52 -0400 Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4H0dGk51d6z8xf7; Thu, 2 Sep 2021 18:59:26 +0800 (CST) Received: from dggpemm500023.china.huawei.com (7.185.36.83) by dggemv711-chm.china.huawei.com (10.1.198.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Thu, 2 Sep 2021 19:03:38 +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 15.1.2308.8; Thu, 2 Sep 2021 19:03:37 +0800 From: Yanan Wang To: Eduardo Habkost , Marcel Apfelbaum , , , , Subject: [PATCH v8 04/14] machine: Set the value of cpus to match maxcpus if it's omitted Date: Thu, 2 Sep 2021 19:03:20 +0800 Message-ID: <20210902110330.18036-5-wangyanan55@huawei.com> X-Mailer: git-send-email 2.8.4.windows.1 In-Reply-To: <20210902110330.18036-1-wangyanan55@huawei.com> References: <20210902110330.18036-1-wangyanan55@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.187.128] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemm500023.china.huawei.com (7.185.36.83) X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.188; envelope-from=wangyanan55@huawei.com; helo=szxga02-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_H2=-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 , Cornelia Huck , =?utf-8?q?Daniel_P_=2E_Berrang=C3=A9?= , Pierre Morel , "Michael S . Tsirkin" , Pankaj Gupta , Greg Kurz , Yanan Wang , wanghaibin.wang@huawei.com, Thomas Huth , Paolo Bonzini , David Gibson Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Currently we directly calculate the omitted cpus based on the given incomplete collection of parameters. This makes some cmdlines like: -smp maxcpus=16 -smp sockets=2,maxcpus=16 -smp sockets=2,dies=2,maxcpus=16 -smp sockets=2,cores=4,maxcpus=16 not work. We should probably set the value of cpus to match maxcpus if it's omitted, which will make above configs start to work. So the calculation logic of cpus/maxcpus after this patch will be: When both maxcpus and cpus are omitted, maxcpus will be calculated from the given parameters and cpus will be set equal to maxcpus. When only one of maxcpus and cpus is given then the omitted one will be set to its counterpart's value. Both maxcpus and cpus may be specified, but maxcpus must be equal to or greater than cpus. Note: change in this patch won't affect any existing working cmdlines but allows more incomplete configs to be valid. Signed-off-by: Yanan Wang Reviewed-by: Andrew Jones --- hw/core/machine.c | 29 ++++++++++++++++------------- hw/i386/pc.c | 29 ++++++++++++++++------------- qemu-options.hx | 11 ++++++++--- 3 files changed, 40 insertions(+), 29 deletions(-) diff --git a/hw/core/machine.c b/hw/core/machine.c index 56bd3033a5..fe935cb4a3 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -760,25 +760,28 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp) } /* compute missing values, prefer sockets over cores over threads */ - maxcpus = maxcpus > 0 ? maxcpus : cpus; - - if (cpus == 0) { + if (cpus == 0 && maxcpus == 0) { sockets = sockets > 0 ? sockets : 1; cores = cores > 0 ? cores : 1; threads = threads > 0 ? threads : 1; - cpus = sockets * cores * threads; + } else { maxcpus = maxcpus > 0 ? maxcpus : cpus; - } else if (sockets == 0) { - cores = cores > 0 ? cores : 1; - threads = threads > 0 ? threads : 1; - sockets = maxcpus / (cores * threads); - } else if (cores == 0) { - threads = threads > 0 ? threads : 1; - cores = maxcpus / (sockets * threads); - } else if (threads == 0) { - threads = maxcpus / (sockets * cores); + + if (sockets == 0) { + cores = cores > 0 ? cores : 1; + threads = threads > 0 ? threads : 1; + sockets = maxcpus / (cores * threads); + } else if (cores == 0) { + threads = threads > 0 ? threads : 1; + cores = maxcpus / (sockets * threads); + } else if (threads == 0) { + threads = maxcpus / (sockets * cores); + } } + maxcpus = maxcpus > 0 ? maxcpus : sockets * cores * threads; + cpus = cpus > 0 ? cpus : maxcpus; + if (sockets * cores * threads < cpus) { error_setg(errp, "cpu topology: " "sockets (%u) * cores (%u) * threads (%u) < " diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 4b67c49f38..cf75fa5c7a 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -727,25 +727,28 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err dies = dies > 0 ? dies : 1; /* compute missing values, prefer sockets over cores over threads */ - maxcpus = maxcpus > 0 ? maxcpus : cpus; - - if (cpus == 0) { + if (cpus == 0 && maxcpus == 0) { sockets = sockets > 0 ? sockets : 1; cores = cores > 0 ? cores : 1; threads = threads > 0 ? threads : 1; - cpus = sockets * dies * cores * threads; + } else { maxcpus = maxcpus > 0 ? maxcpus : cpus; - } else if (sockets == 0) { - cores = cores > 0 ? cores : 1; - threads = threads > 0 ? threads : 1; - sockets = maxcpus / (dies * cores * threads); - } else if (cores == 0) { - threads = threads > 0 ? threads : 1; - cores = maxcpus / (sockets * dies * threads); - } else if (threads == 0) { - threads = maxcpus / (sockets * dies * cores); + + if (sockets == 0) { + cores = cores > 0 ? cores : 1; + threads = threads > 0 ? threads : 1; + sockets = maxcpus / (dies * cores * threads); + } else if (cores == 0) { + threads = threads > 0 ? threads : 1; + cores = maxcpus / (sockets * dies * threads); + } else if (threads == 0) { + threads = maxcpus / (sockets * dies * cores); + } } + maxcpus = maxcpus > 0 ? maxcpus : sockets * dies * cores * threads; + cpus = cpus > 0 ? cpus : maxcpus; + if (sockets * dies * cores * threads < cpus) { error_setg(errp, "cpu topology: " "sockets (%u) * dies (%u) * cores (%u) * threads (%u) < " diff --git a/qemu-options.hx b/qemu-options.hx index aee622f577..06f819177e 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -214,9 +214,14 @@ SRST Simulate a SMP system with '\ ``n``\ ' CPUs initially present on the machine type board. On boards supporting CPU hotplug, the optional '\ ``maxcpus``\ ' parameter can be set to enable further CPUs to be - added at runtime. If omitted the maximum number of CPUs will be - set to match the initial CPU count. Both parameters are subject to - an upper limit that is determined by the specific machine type chosen. + added at runtime. When both parameters are omitted, the maximum number + of CPUs will be calculated from the provided topology members and the + initial CPU count will match the maximum number. When only one of them + is given then the omitted one will be set to its counterpart's value. + Both parameters may be specified, but the maximum number of CPUs must + be equal to or greater than the initial CPU count. Both parameters are + subject to an upper limit that is determined by the specific machine + type chosen. To control reporting of CPU topology information, the number of sockets, dies per socket, cores per die, and threads per core can be specified.