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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C2A37C38145 for ; Sat, 3 Sep 2022 06:00:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231888AbiICGAp (ORCPT ); Sat, 3 Sep 2022 02:00:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229952AbiICGAk (ORCPT ); Sat, 3 Sep 2022 02:00:40 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BCB8F754A3 for ; Fri, 2 Sep 2022 23:00:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 664EE609D1 for ; Sat, 3 Sep 2022 06:00:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EBCCBC433C1; Sat, 3 Sep 2022 06:00:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1662184837; bh=GBgkfGmfM/oXPv3olWCaRFFkrxlDrMDp9b1OTF8aL5Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Bq6TctCasHfGP2OBnCjJq1QFHTPLjL2mt8N6mnPFuaMvB97ITehOv9b6ODLza9fsU b19TJ77LRvKaQbcJHkqg+rpTGEl/CgjIQ3Z/sVzKxIGswnmKNqIKPu831FSqUOpPn4 YCKYqsOzXRglN8BTRrEsez2KWyzxhePj70VmJoyQ= Date: Sat, 3 Sep 2022 08:00:55 +0200 From: Greg KH To: Yicong Yang Cc: sudeep.holla@arm.com, vincent.guittot@linaro.org, ionela.voinescu@arm.com, linux-kernel@vger.kernel.org, rafael@kernel.org, 21cnbao@gmail.com, jonathan.cameron@huawei.com, linuxarm@huawei.com, prime.zeng@huawei.com, yangyicong@hisilicon.com Subject: Re: [PATCH v2] arch_topology: Make cluster topology span at least SMT CPUs Message-ID: References: <20220825092007.8129-1-yangyicong@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220825092007.8129-1-yangyicong@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 25, 2022 at 05:20:07PM +0800, Yicong Yang wrote: > 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 when building with CONFIG_SCHED_CLUSTER=y. > > Test with: > qemu-system-aarch64 -enable-kvm -machine virt \ > -net none \ > -cpu host \ > -bios ./QEMU_EFI.fd \ > -m 2G \ > -smp 48,sockets=2,cores=12,threads=2 \ > -kernel $Image \ > -initrd $Rootfs \ > -nographic \ > -append "rdinit=init console=ttyAMA0 sched_verbose loglevel=8" > > 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: Sudeep Holla > Reviewed-by: Ionela Voinescu > --- > Change since v1: > - mention the kernel config CONFIG_SCHED_CLUSTER=y, per Ionela > Link:https://lore.kernel.org/lkml/20220823073044.58697-1-yangyicong@huawei.com/ > > 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); As the kernel-test robot reported, this breaks the build on some architectures, so I'll go and revert it from my tree now. thanks, greg k-h