From patchwork Tue Aug 3 08:05:16 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "wangyanan (Y)" X-Patchwork-Id: 1512785 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 4Gf6xv42Ywz9s5R for ; Tue, 3 Aug 2021 18:10:43 +1000 (AEST) Received: from localhost ([::1]:37690 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mApVZ-0003iu-6W for incoming@patchwork.ozlabs.org; Tue, 03 Aug 2021 04:10:41 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34650) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mApQq-0000wm-EG for qemu-devel@nongnu.org; Tue, 03 Aug 2021 04:05:48 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:2170) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mApQl-00044O-KQ for qemu-devel@nongnu.org; Tue, 03 Aug 2021 04:05:48 -0400 Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Gf6lZ3QqTz83PT; Tue, 3 Aug 2021 16:01:46 +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; Tue, 3 Aug 2021 16:05:34 +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; Tue, 3 Aug 2021 16:05:33 +0800 From: Yanan Wang To: Subject: [PATCH for-6.2 v4 03/14] machine: Set the value of cpus to match maxcpus if it's omitted Date: Tue, 3 Aug 2021 16:05:16 +0800 Message-ID: <20210803080527.156556-4-wangyanan55@huawei.com> X-Mailer: git-send-email 2.8.4.windows.1 In-Reply-To: <20210803080527.156556-1-wangyanan55@huawei.com> References: <20210803080527.156556-1-wangyanan55@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.187.128] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) 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_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 , Cornelia Huck , =?utf-8?q?Daniel_P_=2E_Berrang=C3=A9?= , Eduardo Habkost , Pierre Morel , "Michael S . Tsirkin" , Pankaj Gupta , Richard Henderson , Greg Kurz , Halil Pasic , yuzenghui@huawei.com, wanghaibin.wang@huawei.com, Thomas Huth , Paolo Bonzini , Yanan Wang , 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. Reviewed-by: Andrew Jones Signed-off-by: Yanan Wang --- 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 69979c93dd..958e6e7107 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -755,25 +755,28 @@ 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 a9ff9ef52c..9ad7ae5254 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -725,25 +725,28 @@ 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.