From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from SN4PR0501CU005.outbound.protection.outlook.com (mail-southcentralusazon11011011.outbound.protection.outlook.com [40.93.194.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5007E156CA; Tue, 28 Apr 2026 20:42:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.93.194.11 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777408922; cv=fail; b=PgiS2Inoi/BpWq9d4DSg9RmXDZ3dvDs3VRIe7UfllAPtrKg94+5eJ5f2Fz5XiSosEbwoiy2bnvFdF48h/s26SYYzv0j+Vlw2zOdutHk59N/v1puvIVonwCoFJ6ALYT9R7rYKIhCu4e+yFJwaCvwqLLRsuX3x/ifBbTsE6Ct+T/c= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777408922; c=relaxed/simple; bh=sQIHzIyFnffoQqKMdZhmA7JZF46LsQC/2pSbdxEnIHM=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=sNzudpJ8DZsvlBkYml4itAmulvCX9/HitGraU30ZE7hfzphbzBl0ttONooRM1pYYaIAL82qQA3rCSTBsnSZahxrCXFtIk6fKo/hz4LjzdQiFp6erMIpnEHKh0oihoiYBV2Bne4WjZpBuNTMvr9fpMZV2LXngRsl4tztu3ZaLWKE= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b=oE3biab3; arc=fail smtp.client-ip=40.93.194.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b="oE3biab3" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=v3f4KP8EF/Vlyr0ZAMsF7E0d7HZzppRpZW98ItEfX+d+A1FLhm88zCj1lgUvbgBiNEFJy1MbH6vGV8LYfhO11vnnzaAYHKEIkq5UZf4RdjLSpHnmeKL7oaOpDCf+JopBsYpPqa30q4T3V3O8C4gRB9zU8esmt7gLzPsRNq+fVGb/ZCHt6TgVevN0GsXGkfxXtwCHcZupQCeq4djZIHlGtUy8JTXgmom9gqOB1Y/X8SirZAvE7LAh/wLojXWMPXTbooq4nHUmFbNdDjzqgyasDSexd/V0ol3uRCrgbDG4xwSW6zfh6e4Ry+n+xmBRZQMpCKE4vELttrUe1VBdbvQpPA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=j4mH9QYIZFqWg2IWqarAcGzZjvtcmhdY1/y2SDd6is8=; b=mqQ9r5PD4IW29hMZzPGBz2Lu1MpkbJeJvlF4i07+MqdoJvIhiUjc7UnKEVLCSrsJAVVo75vFOZ+Dl/NyHMqTjqVXWhZ34EtIymKZRxFwGH1oXxH83YEz0kZNiFzL9UASOnaCW0tN2gYK3vhvFHrzsbEYNpNgalfMUVdVBdx1KqGP+nB/lsjjziYjNrQ74KudDK3Io6BHxG4ffodT9YdILmZom+lnd4ZYzUJIOAql5aVsmdmjIVn1+PVQmCznW6DJb+M+KqV0S9U/Q29/wwLlERaBR0bk2wwp9myGjFNSAEEdaWpe7PSBZVG5bO6zFjsXHd+0jcjLzlGgVd2VwjIbrQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=j4mH9QYIZFqWg2IWqarAcGzZjvtcmhdY1/y2SDd6is8=; b=oE3biab3EcFaJgufWRSCl/lXS2zS9SjARxEkUhoc84tRV3Pzg2s05wK2So9HYlaauMzAk/urlQOmpoQIzMm18dO7Ac0unoMM2QWd2DnT1NnmKH2iBkJ/IaTyqLMaASRoiScDNKbb8Ypfgv1NRn0Hy88oyILTUT8ZeM3dVdITvOo= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from IA0PPF9A76BB3A6.namprd12.prod.outlook.com (2603:10b6:20f:fc04::bdc) by SJ0PR12MB6784.namprd12.prod.outlook.com (2603:10b6:a03:44f::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9870.16; Tue, 28 Apr 2026 20:41:54 +0000 Received: from IA0PPF9A76BB3A6.namprd12.prod.outlook.com ([fe80::ca9:67f1:6872:decc]) by IA0PPF9A76BB3A6.namprd12.prod.outlook.com ([fe80::ca9:67f1:6872:decc%6]) with mapi id 15.20.9846.025; Tue, 28 Apr 2026 20:41:54 +0000 Message-ID: <37ac0376-43a3-4283-a3d5-4d57b3bec578@amd.com> Date: Tue, 28 Apr 2026 15:41:51 -0500 User-Agent: Mozilla Thunderbird Subject: Re: [tip: x86/urgent] x86/resctrl: Fix SNC detection To: linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org, "tony.luck@intel.com" , Reinette Chatre Cc: Tony Luck , "Peter Zijlstra (Intel)" , Ingo Molnar , Zhang Rui , Chen Yu , x86@kernel.org References: <20260303110100.367976706@infradead.org> <177263917393.1647592.6057050710859194701.tip-bot2@tip-bot2> Content-Language: en-US From: Babu Moger In-Reply-To: <177263917393.1647592.6057050710859194701.tip-bot2@tip-bot2> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SA9P221CA0023.NAMP221.PROD.OUTLOOK.COM (2603:10b6:806:25::28) To IA0PPF9A76BB3A6.namprd12.prod.outlook.com (2603:10b6:20f:fc04::bdc) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: IA0PPF9A76BB3A6:EE_|SJ0PR12MB6784:EE_ X-MS-Office365-Filtering-Correlation-Id: 2b05db8e-0451-43ed-1a14-08dea56694ec X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|1800799024|56012099003|22082099003|18002099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:IA0PPF9A76BB3A6.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(376014)(366016)(1800799024)(56012099003)(22082099003)(18002099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?VkI0VHN0RzcwRlBmM21FQmpnb0VuTmxiNEZudlFPRVp1c3lTaDdhaVd6SHlL?= =?utf-8?B?cWk0SmNtUSs1NDdBQW4rSjREMGR2VDFVSVBsRE42UG9RRDdlR0g5ODZLRnlG?= =?utf-8?B?YlZGellTbEhrOG81MlZxb3IzK0hUYXVEaTJsUXArRW9ob2dGMGRSRmNaTVVT?= =?utf-8?B?V2I0WkplS2NGVldvY1VrL0ZTY2p5eHd1K0p6TS9na1Vrd29pWkJqMk5YcWlS?= =?utf-8?B?KzcwRW1MU3pPcHRSbDUyOFUvcmw5SUxBeUtaZDJka3hJTS9vdnJmQTlpUi80?= =?utf-8?B?Tm54eE5yMDl6cEE3RndraGlTRUhlVjI4a0hwbTlSTWdycFo3bFROZVhpejY0?= =?utf-8?B?cms5Y2pMaFFTNEZlb1dXMWI3M0hva0hpbHd1R0JhNUg3Yjd0TmtENzNKT1pV?= =?utf-8?B?QVFDZ3pMS09iV3hKU0NsMHQzcEo0cGF6aWRObENLS1BibHI4SzVWT2VISkhh?= =?utf-8?B?K1BoTHBVazhsVkJ4NlYveERTUDF3QVIrTmZ4NEQwUC9VK0J3dFlmVk1hUnI3?= =?utf-8?B?S0F6RUl5d1ZGMXQ5azFxeDBjN0tOOTJnQ0FwMkNxRnVIaUdVRERaUHoyaS9K?= =?utf-8?B?eFVONWZGQ1FnTHVFamVlN2RnNjFTRFlFc3lJOXd5dnZTSnpvMjBSQlZoUDdI?= =?utf-8?B?VlNDUFNMNSs4dW1uSFdHMGxTR3hwMEJqY2JZUkZkY3pnejB0U0RLVkVQbUhq?= =?utf-8?B?clZmM0VwOHd3b0ZYZHRPS2RpcHg5RW4vTmNYVkRrb29MQzdFaTkrTk9LWDhp?= =?utf-8?B?TW9uV0oyclBPb1BTL3BxOVJ2UGg4RzJtN0k0ZUJrM1cxYXhFYlE0YVFNWEM3?= =?utf-8?B?bXRPakpOZHV5Uk9zMnlMcUZhTm02Wm1tU1NTWnV4SE9PbkxVRDJaYWx5aThL?= =?utf-8?B?aFF5UmV3R2g4b1lrTmFFbWZkNXFLUVA2Y2JBNy9LUG8vNTFNdnhIdGVFMTh2?= =?utf-8?B?Q3VENTdzeGNGT21YQXhKWVFlTTBzazY2Z3J4SlZDeUJZdU1wbmhaWFB5c01h?= =?utf-8?B?TWl5Sy9DN2VSaForU1pPRFltUXdUMko5WGdBOVh0ZElmb3ZST29kbFZpTTlF?= =?utf-8?B?YUR5eDFyT0NOeVN3Z0Q1NndzT2VUenlHbnNUTmNaRXREby9XZUltMkxaQk5u?= =?utf-8?B?OE1UdGpMaHhHR3VaMGtqWHpIK0NXdlVNbURKSS9FeFBtREdwN0RlRnphYlRi?= =?utf-8?B?WmRhM3QxaURJR1VaWnphWEo2a0s2REI4L3NubnhhVHpORXQ2cnNzWG0zTDdI?= =?utf-8?B?amVOQXp1VmF3NUlJTDk1Q2pqdHUvOG0vam1HaGJMYmYzcXQvVVZpUkdaakRa?= =?utf-8?B?eG1oWHlUSm5sbmVMRE80b29ENExOUzRFSEJ5akJhTDdaQWd6RHNyQm1LK28y?= =?utf-8?B?WHFPQlZneDVuSXlnYTk0bnFEbzJHMnZ2L1dwZEFGdy92UFpQb0xpWnZmSDQ3?= =?utf-8?B?NEtZaXA2YmRJc3QzQkRGNm4rSzJRMVk1QzVyNURPZTlMK2FyeUE3eTZOc2x1?= =?utf-8?B?bytFRm94OWljMGFKZEp5cGdJRWtGdzdHUEFmSDFBZWNyVGRCelN1cW13bFBl?= =?utf-8?B?dlMxSHhpL1B2NmlLdUJ4U1J6SE5lRHNnUTArdzBOdDBKdG5GQXJhOE55cDBV?= =?utf-8?B?L3hUS3dtVk1ZR1hjbU0zWGZtNHRkdFAwS0RrbkJrZnEwWE8xOVNHMVljdW9J?= =?utf-8?B?RjhndzB3OFdyakM2Z1dmS2MvMjRLMWRvS0FNQndXOGdYUTA4L0pEekZxWHZo?= =?utf-8?B?eVFIbHNtaG5hcmtFNS9vU3NJa2djeUtZZXFsOUJZZDh3bGxLc0drWEJZSGJx?= =?utf-8?B?Z1BKRGRhZnpBOUJrM0FLSVV6REtDdkR2dVAvUEtoYUNmUTZhUzUyQXp5VDZG?= =?utf-8?B?MzZxTFBrZWVkQ04zZnlDekZiSGE0UlN6Z1BVMHYxN0FZM1RTMTQxMHdRSnFO?= =?utf-8?B?ZnNZUGVQdjFOWGFTV3RMZ3lHeWc3elptNUZER3FBNi9kcHZRZDlOKzkyb1d4?= =?utf-8?B?Yndhd0tlY1Fld0RKeXF1dGoySnVOS2hpOGVaWlZWRlhNUVV6MFNXWmU5bUpx?= =?utf-8?B?ZkxSUVlIZkJxeUxtak5uMHdFQ1p4SlhBT2c1WE9wRmlRQ21vM2FaVGZtMits?= =?utf-8?B?ajRaOUpNcUJTQldqY214NXh6THo4WEFjQnVLUXFFUWhJdWpWLzFBR0hzeWRU?= =?utf-8?B?QnNMTzY4SXNsV3BRcVpqV1dHMVNFNEZiakc3MmVQL1VZRDJqYnpHaklZSEZz?= =?utf-8?B?eWxjOE1ldkFHOTRDcFdENGJaTWc0ejVTcDd0MGJkZDJvQ25KK1ZQSVdDWWx4?= =?utf-8?Q?c4/bZOVcGMIICf/tKt?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2b05db8e-0451-43ed-1a14-08dea56694ec X-MS-Exchange-CrossTenant-AuthSource: IA0PPF9A76BB3A6.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Apr 2026 20:41:53.9911 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: WqcUD7kMM0PhJoE4QwUF7ZXY+0iYxN5ujCxbuVet4nQIsyRT/EQfl80vKiA40TWF X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR12MB6784 Hi Tony, On 3/4/26 09:46, tip-bot2 for Tony Luck wrote: > The following commit has been merged into the x86/urgent branch of tip: > > Commit-ID: 59674fc9d0bfd96ce8a776680ee1cf22c28c9ac7 > Gitweb: https://git.kernel.org/tip/59674fc9d0bfd96ce8a776680ee1cf22c28c9ac7 > Author: Tony Luck > AuthorDate: Tue, 03 Mar 2026 11:55:44 +01:00 > Committer: Peter Zijlstra > CommitterDate: Wed, 04 Mar 2026 16:35:09 +01:00 > > x86/resctrl: Fix SNC detection > > Now that the x86 topology code has a sensible nodes-per-package > measure, that does not depend on the online status of CPUs, use this > to divinate the SNC mode. > > Note that when Cluster on Die (CoD) is configured on older systems this > will also show multiple NUMA nodes per package. Intel Resource Director > Technology is incomaptible with CoD. Print a warning and do not use the > fixup MSR_RMID_SNC_CONFIG. > > Signed-off-by: Tony Luck > Signed-off-by: Peter Zijlstra (Intel) > Reviewed-by: Ingo Molnar > Tested-by: Zhang Rui > Tested-by: Chen Yu > Link: https://patch.msgid.link/aaCxbbgjL6OZ6VMd@agluck-desk3 > Link: https://patch.msgid.link/20260303110100.367976706@infradead.org > --- > arch/x86/kernel/cpu/resctrl/monitor.c | 36 +++----------------------- > 1 file changed, 5 insertions(+), 31 deletions(-) > > diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c > index e6a1542..9bd87ba 100644 > --- a/arch/x86/kernel/cpu/resctrl/monitor.c > +++ b/arch/x86/kernel/cpu/resctrl/monitor.c > @@ -364,7 +364,7 @@ void arch_mon_domain_online(struct rdt_resource *r, struct rdt_l3_mon_domain *d) > msr_clear_bit(MSR_RMID_SNC_CONFIG, 0); > } > > -/* CPU models that support MSR_RMID_SNC_CONFIG */ > +/* CPU models that support SNC and MSR_RMID_SNC_CONFIG */ > static const struct x86_cpu_id snc_cpu_ids[] __initconst = { > X86_MATCH_VFM(INTEL_ICELAKE_X, 0), > X86_MATCH_VFM(INTEL_SAPPHIRERAPIDS_X, 0), > @@ -375,40 +375,14 @@ static const struct x86_cpu_id snc_cpu_ids[] __initconst = { > {} > }; > > -/* > - * There isn't a simple hardware bit that indicates whether a CPU is running > - * in Sub-NUMA Cluster (SNC) mode. Infer the state by comparing the > - * number of CPUs sharing the L3 cache with CPU0 to the number of CPUs in > - * the same NUMA node as CPU0. > - * It is not possible to accurately determine SNC state if the system is > - * booted with a maxcpus=N parameter. That distorts the ratio of SNC nodes > - * to L3 caches. It will be OK if system is booted with hyperthreading > - * disabled (since this doesn't affect the ratio). > - */ > static __init int snc_get_config(void) > { > - struct cacheinfo *ci = get_cpu_cacheinfo_level(0, RESCTRL_L3_CACHE); > - const cpumask_t *node0_cpumask; > - int cpus_per_node, cpus_per_l3; > - int ret; > - > - if (!x86_match_cpu(snc_cpu_ids) || !ci) > - return 1; > + int ret = topology_num_nodes_per_package(); > > - cpus_read_lock(); > - if (num_online_cpus() != num_present_cpus()) > - pr_warn("Some CPUs offline, SNC detection may be incorrect\n"); > - cpus_read_unlock(); Saw these messages on AMD system(7.1.0-rc1). sudo dmesg |grep CoD [ 6.614667] resctrl: CoD enabled system? Resctrl not supported Might confuse some users. Not a big deal. But we should fix it in next version. Thanks Babu