From nobody Wed Apr 8 06:24:00 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 20CF4C32789 for ; Tue, 23 Aug 2022 07:33:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240520AbiHWHdN (ORCPT ); Tue, 23 Aug 2022 03:33:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40354 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237115AbiHWHdK (ORCPT ); Tue, 23 Aug 2022 03:33:10 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7D45562ABA for ; Tue, 23 Aug 2022 00:33:08 -0700 (PDT) Received: from canpemm500009.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4MBgnm01NMzXdnp; Tue, 23 Aug 2022 15:28:43 +0800 (CST) Received: from localhost.localdomain (10.67.164.66) by canpemm500009.china.huawei.com (7.192.105.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 23 Aug 2022 15:33:00 +0800 From: Yicong Yang To: , , , CC: , , <21cnbao@gmail.com>, , , , Subject: [PATCH] arch_topology: Make cluster topology span at least SMT CPUs Date: Tue, 23 Aug 2022 15:30:44 +0800 Message-ID: <20220823073044.58697-1-yangyicong@huawei.com> X-Mailer: git-send-email 2.31.0 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.67.164.66] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500009.china.huawei.com (7.192.105.203) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Yicong Yang Currently cpu_clustergroup_mask() will return CPU mask if cluster span more or the same CPUs as cpu_coregroup_mask(). This will result topology borken on non-Cluster SMT machines. Test with: qemu-system-aarch64 -enable-kvm -machine virt \ -net none \ -cpu host \ -bios ./QEMU_EFI.fd \ -m 2G \ -smp 48,sockets=3D2,cores=3D12,threads=3D2 \ -kernel $Image \ -initrd $Rootfs \ -nographic -append "rdinit=3Dinit console=3DttyAMA0 sched_verbose loglevel=3D8" We'll get below error: [ 3.084568] BUG: arch topology borken [ 3.084570] the SMT domain not a subset of the CLS domain Since cluster is a level higher than SMT, fix this by making cluster spans at least SMT CPUs. Cc: Sudeep Holla Cc: Vincent Guittot Cc: Ionela Voinescu Fixes: bfcc4397435d ("arch_topology: Limit span of cpu_clustergroup_mask()") Signed-off-by: Yicong Yang Reviewed-by: Ionela Voinescu Reviewed-by: Sudeep Holla --- drivers/base/arch_topology.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index 0424b59b695e..0056a1273275 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -724,7 +724,7 @@ const struct cpumask *cpu_clustergroup_mask(int cpu) */ if (cpumask_subset(cpu_coregroup_mask(cpu), &cpu_topology[cpu].cluster_sibling)) - return get_cpu_mask(cpu); + return cpu_smt_mask(cpu); =20 return &cpu_topology[cpu].cluster_sibling; } --=20 2.24.0