From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.16]) (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 A9762375ADE for ; Fri, 21 Aug 2026 18:19:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=192.198.163.16 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787336347; cv=fail; b=WXrMc3SwQ6q96zrS3sE7lWj4weE7bhlXLn9xnLBgDVPJCyFqnwdHBhSHzUFqCpOqSZSLCBKwy0Ze7HGggIWW5kQ6xnL2R0BLtucaXRAnppukEjRSiXMC//9AGDvUbxwqJCUinYf36hv1Qt64ypAKsPOzM/i1iYVQWKN0nNsHfgQ= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787336347; c=relaxed/simple; bh=VxQnzJ2KeTljhSsxBO48thdC93TZ5l0p7xaXUAlqsDE=; h=Message-ID:Date:Subject:To:CC:References:From:In-Reply-To: Content-Type:MIME-Version; b=n71vsa1SQUzZCL6vvmhxk8OSUMKLV0GvRVyPio4K044d9Cxmjek/hveDYVxuF9N6ujDi/GlVB3mvSuDNELM1bvgk3WnyL7yQk+toILDXms6qL2SWaKbOonaHeS2l5fgaE8Na3+3MqyM56OUpc+abGvi28ewhqA2lEuN968a5jqg= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=eAzzVnzR; arc=fail smtp.client-ip=192.198.163.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="eAzzVnzR" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1787336344; x=1818872344; h=message-id:date:subject:to:cc:references:from: in-reply-to:content-transfer-encoding:mime-version; bh=VxQnzJ2KeTljhSsxBO48thdC93TZ5l0p7xaXUAlqsDE=; b=eAzzVnzR61RZr4E82C/TrLgre57q/RR3dbWWHl/3j727aqlLwf65AJrD biF+o1eGvc9zQBj80lD37P1y9TTdIXNs4HJpvkiCZKrcupRc4aqjUudUo heI0cE1que0y/QkeHz6YijU8/tqNozuGOkha5H13TVQ8v+Vq67icnr1lk aQu67dGM2pj/9xpTtHYOp6pxtMRYNne0IBVhkuVh8H9AXwPJ6RJeYSMr7 NsauJE7MBfSMypvAdNGiSvC7cn5S7wu+N20+eBJ2WW/gfYCF5oUNOJ7ur YD07nTj5bWB+5NaLcemuRREzhdaOjlCg0S+TvFvFQ20SAUzu06C3LlWzL Q==; X-CSE-ConnectionGUID: YZIqkjOeQwqNyUKPP0Bu+w== X-CSE-MsgGUID: js6TLeFlTLCNJdvfPeRGSQ== X-IronPort-AV: E=McAfee;i="6800,10657,11882"; a="75429660" X-IronPort-AV: E=Sophos;i="6.25,235,1779174000"; d="scan'208";a="75429660" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by fmvoesa110.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Aug 2026 11:19:04 -0700 X-CSE-ConnectionGUID: Hz4fZIL1T6iWJ/wAiPXyUA== X-CSE-MsgGUID: CYd/1CyTRH6z6+UcKe3iRQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,235,1779174000"; d="scan'208";a="263132214" Received: from fmsmsx903.amr.corp.intel.com ([10.18.126.92]) by fmviesa007.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Aug 2026 11:19:04 -0700 Received: from FMSMSX902.amr.corp.intel.com (10.18.126.91) by fmsmsx903.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.45; Fri, 21 Aug 2026 11:19:03 -0700 Received: from fmsedg903.ED.cps.intel.com (10.1.192.145) by FMSMSX902.amr.corp.intel.com (10.18.126.91) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.45 via Frontend Transport; Fri, 21 Aug 2026 11:19:03 -0700 Received: from SJ2PR03CU001.outbound.protection.outlook.com (52.101.43.37) by edgegateway.intel.com (192.55.55.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.45; Fri, 21 Aug 2026 11:19:02 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=rw7o/CeESjrnUjQlvku+rUl2f9Cvk87ezhLwztHYGaZL/R1PHQvJRXajyFtxrxDYJ6+x0hCUx4MUmAoWW6mSHjEeCbNLTXu0cqwAzW9t7UiVsb/ZujoEdyyziDQ/7XIqqdXS6qVa7Gn4PIj4DHwiPk0yGKxQeFfet7BMyDid2jRsFKjVfRlnnMiqHo7ZfhLFvtFmumKguprqS5wwNY5LIwQJBuTzfV31IzTan3bwwRQ1XrHuRYZk2bvvQlFGWg3kxF3kP5um4pC8+Cr5BnOHp4MXSr9nPlNkYehu+jkUIwzu2OyJq6sxDNOgVdMtFQxTwiWmiEorjK3Y0m6jE5KtWg== 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=Yr3Rz2vARKweHqJzE4xuIVxTDd8esON2afW68n3hwxs=; b=IvWUOYCMqnoDJCoce0I1IlOyO8SZy6TYUpsI4QMlWd8rOwZG2wC6HnhWbJ4sAXAvzMKLdNXWQqfRmECB5VkiS3EdqWdXjFFY1plZoVeBgdH3u1htk8/18pLTCj6Mj+HWNnTEr1plo+nyIL060kglaQaGrkuTdcOK+YmQqbZdEduExUPXnvOiR66GZowh2EPx5BHVUx5ePm3cvfdAGnLF5ey0xSFYKiEl18qkl10/mh9tTuHXVMLnm72UsaKV27Fv8GMUIdal3d1pvBtkporBZOx5K3sKetGgrI0O3LQTrPsK+mEvbN952B9ZeE7uA5rx66QjNY6tkN3ET60q3N13Hg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=intel.com; Received: from SJ2PR11MB8370.namprd11.prod.outlook.com (2603:10b6:a03:540::20) by LV2PR11MB727748.namprd11.prod.outlook.com (2603:10b6:408:413::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.339.11; Fri, 21 Aug 2026 18:19:01 +0000 Received: from SJ2PR11MB8370.namprd11.prod.outlook.com ([fe80::b6cf:ce77:3cdf:7cc]) by SJ2PR11MB8370.namprd11.prod.outlook.com ([fe80::b6cf:ce77:3cdf:7cc%5]) with mapi id 15.21.0339.010; Fri, 21 Aug 2026 18:19:00 +0000 Message-ID: <9787f9de-c72d-4c0d-b9a9-867b0f4377f5@intel.com> Date: Fri, 21 Aug 2026 11:18:51 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 1/4] x86/resctrl: Check if monitoring features are enabled To: Tony Luck , Fenghua Yu , "Maciej Wieczor-Retman" , Peter Newman , James Morse , Babu Moger , Drew Fustini , Dave Martin , Chen Yu , CC: , References: <20260819161323.11587-1-tony.luck@intel.com> <20260819161323.11587-2-tony.luck@intel.com> From: Reinette Chatre Content-Language: en-US In-Reply-To: <20260819161323.11587-2-tony.luck@intel.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: MW4PR03CA0007.namprd03.prod.outlook.com (2603:10b6:303:8f::12) To SJ2PR11MB8370.namprd11.prod.outlook.com (2603:10b6:a03:540::20) 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: SJ2PR11MB8370:EE_|LV2PR11MB727748:EE_ X-MS-Office365-Filtering-Correlation-Id: 080a18a3-9346-4b69-6717-08deffb0abbd X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|376014|23010399003|366016|921020|18002099003|22082099003|10067099003|11063799006|4143699003|56012099006; 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:SJ2PR11MB8370.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(376014)(23010399003)(366016)(921020)(18002099003)(22082099003)(10067099003)(11063799006)(4143699003)(56012099006);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?cFdkdDN3RDRFZWV2QVNRNDRqbG9vSXZZRkxRWlhGNlRlY1pCVCthQjNLZVhW?= =?utf-8?B?K0xPMlFSSFhOV1NnZk0xbjFPZTdBUG9kcjVWQzBkN0dCd1JQQ3RYOThyQWJu?= =?utf-8?B?T0ZzYU9QVEt1YkVxUmtNbHFtOFFEVkQwdzdUcDg1V3l6UTZpODBxK3lCTjRw?= =?utf-8?B?Y08xWWZCZ201R25RRTNGM296cGhheDc0YTFxWGcya3BLRituL3pYcGNmeDVF?= =?utf-8?B?Y2JoK05GdFh6Rmd3Y2c3cWE5azBKc01qcGJ0VVpWWkdjVlkwWC8rQTdCdkQ0?= =?utf-8?B?dzRNM2dZSkhVUGlRWkl2ZHczUDNxL2V2c0Mwem9NYWlwZlRHdUd4WWRFRXlI?= =?utf-8?B?czFRZjU0ZWZJbzFlRzl3OUQ1cHJDYXlGL0xrVUttMThwaWhoQlhrSWdDNTkr?= =?utf-8?B?MEMybzV6S0kvUkhncWxYTW9PMVZ5Slp1Zm9TQklnaTlxT0hjeWVRZkd1aWh4?= =?utf-8?B?aGVzRmd1bWRmVVBuYVhFMW44dGttT1M4WHdwZXNlRWNZdzZTd3dZdERtRnJ2?= =?utf-8?B?SXBhZGM5eU04SUhIMGFKZ0tET29sZ0hXM3ppMDRqNk14QVdkckJtaGFKb0tZ?= =?utf-8?B?aXNuVDZCUjN1M2plS2hGVThvYk1PMENKQ3kvalVRcW8xUkNpck1aSHNaQzBG?= =?utf-8?B?bDhBS2ZKVlcxMlNpY0UveEJ3TU1sTUVQY1hiVFpPZFFuTXl5L0xOd0hFdzlE?= =?utf-8?B?WTdwdEFkTlNUVkozc3RLeVg5ejFtUWhTby83NmtheWU1Qk40bCtCenZJU2Zi?= =?utf-8?B?VHhrbmYzOVNBWGphek9xaHc5MjZ6S3l1TGNpOS9Tb05jZEwwT2tSVEpSaStB?= =?utf-8?B?aGkrZGJWcmt1MzNYajl3ZWlGK0QrSkM1c1ZxTVdnUVFmOVZ0TDAxWnUxMlRi?= =?utf-8?B?SkFtY3EzTVdiQys2WVJQOTR4bHdqbWdrei9CbmxneUpsTTRwT05RbUVabWRY?= =?utf-8?B?U0svMjZIRlVtZC9WeUdqQWcxSUFPU0pKbEJuRjArb1M2MFExcEZWZDNOaDk4?= =?utf-8?B?M2RPZU1NSTI2ZUJkQ09JS0t1bytXRnliVHZWOEthdGMwTWRZLzB4UEU5S1pY?= =?utf-8?B?WExZT0drMlBTVk1yMEwzVC9ZK3haQU83c0F0Z2hta2cxemhSZk1wT05GQW9z?= =?utf-8?B?d0p0a0tzMUtqb0haRmdIYW5CbHNCK3ZZbU1USFF6SWpmZGkrL1ZrRkFBWTEv?= =?utf-8?B?K29JZUl0U2UvRkFYMEJIcjNOYWVqZStuWXFuL1JnOGZPK3pOY3lzbnRQRWR0?= =?utf-8?B?WjV2dU5zTXYvbWN3UFlYUHZVc3JtVytZbTVyRkhSdk1KbTZsQ1pkWXdoelh6?= =?utf-8?B?RUVyT2d4TXFxaU91ZFdYUEpvM1ExaFo1R3NvYW1DeEh6RE41MDE3TW83UWpQ?= =?utf-8?B?NFpkV0RhUkR0ZW5rMVN2SGluYVI0b25CWkFockE2UXlqajVPWTUxM1BMOVRr?= =?utf-8?B?OTcvWEVFNG9ENjVLM3hYT2hqUVZDamxZOGx4SWhidjhzU3A5cTBvSjVkTXdp?= =?utf-8?B?aks2ZGNLakQwWkIwRjVEK25ObGNPaEczSjNuckdGcGZJKzYvOGdUOWFBbU1D?= =?utf-8?B?c1h3bmh6ZUhHc1JOakowWmtzdm8xVG5EamdEeXN4bXVYcFNDNVpOWmdJbnFF?= =?utf-8?B?RU4zSjEzdjNpT2NRL0xRd01kcVladHZwRjQ1TGM3VUxvbVQrcEtEaXpMWEkz?= =?utf-8?B?dXJrYzR4U3ByaXRhMXAxS0lQLzNzNUV2YTFUbGpJMEo2Ri9JUUZkTFFYUE5J?= =?utf-8?B?NjVDRW1OeEU5NXhZUE1DRHFhZVRSdE9tRCtkY1NobjdCOVloZHQ4RUd6R3BP?= =?utf-8?B?d1hiVklxdm9vQVVncG82NlBwNVVXQzRDQTN4M1pkTkpGeVBwOGVQNFcydkFu?= =?utf-8?B?S0pmY1JYSWNoNFBnVnlnWUlSUHBURzFQSUl2a0NOeEhtNTFwTlBEZ0xNRVdh?= =?utf-8?B?RUlxOFI5Wi9lNExBTnFLVlZlYW5xWVRtUm1NWGVGVjJIOTVoOHBSSTFKcE1H?= =?utf-8?B?eW9qTHFaOW9tOFdZOERIMngvT0NTdURZYmljaFdQclI0STJwUi9tWjYxbzBk?= =?utf-8?B?YnpFTWladisvK0MrWHVncWNDRGd2UDdmWjU1YjU4bzVmTmpiS0ZzQkNYOUFJ?= =?utf-8?B?YXhhSHhNYnFSWVB3UjVWR1BrSUliNDNCcERadDYrelhWcEtYUXJNNzNOd1g0?= =?utf-8?B?RWwrRDg1TzBSYjNXMjlsMFhYWVFWUXRFNXYwcUxUc1Q3ZmdWL2NDb3hpTU55?= =?utf-8?B?SDdiSVNmRGVwYThENm0waWtCUzE2Q0V3dE1tS2I2bm4xZDVGSDBhVm0rRGFF?= =?utf-8?B?UWNZeDFFSHdZSjFhbWpIUXBlVzBOZWVEUFRVK043N0pXK0RRejRYVXZGSVNG?= =?utf-8?Q?LqBGtwIJ8pA560M4=3D?= X-Exchange-RoutingPolicyChecked: mP4oJiioBebrSYVQkMqMbppRTuan+5p+gsxLG3Qbx1afI5LwaAK+9todC8CYHndrCmqPcmn2/C3DufFK3/HqVkl5ivQxaZ2m+Z/WAKcDKGnKj2qhea0eG4jhJpOEP9q3pzOOOwPIogpet7mx9W+ZZjFPBvc9egPaO7CMST1yuK6xMOi7kjrQ7nYZxVpajj63Etl3lklA/RqMbR5rJYCroCsmkLc9C4gplqY3WTUHP10n9U35NXCSzKmW3orbOOnuannMqGjD30abJ/VyRd5TZUIDhGYxvIkUhbntYvVJRjRLgDm49F4gqt4Xbc8r7QBu8auS23PIl8/KKAuYKs7Tmw== X-MS-Exchange-CrossTenant-Network-Message-Id: 080a18a3-9346-4b69-6717-08deffb0abbd X-MS-Exchange-CrossTenant-AuthSource: SJ2PR11MB8370.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Aug 2026 18:19:00.8246 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: kCtNVDbyeGcToKyQ4LgI3S8gh6eTwugh5jOpjpkWq9DtI9RxpRDwUzQCIpB2PQ7frcxmH2pJHj5uvwLv1OLO27ugg7IkG5nAQQ+QVkRGpsY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV2PR11MB727748 X-OriginatorOrg: intel.com Hi Tony, Thank you for doing this. On 8/19/26 9:13 AM, Tony Luck wrote: > Both Intel and AMD manuals say that software must first check > CPUID(0x7,0x0).EBX[12] to see if any monitoring features are enabled > before checking for specific features enabled in subleaves. > > Add the check for X86_FEATURE_CQM. > > Fixes: cbc82b172638 ("x86: Add support for Intel Cache QoS Monitoring (CQM) detection") > Signed-off-by: Tony Luck > --- > arch/x86/kernel/cpu/resctrl/core.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c > index 55214d6fdc49..2677b8a6c15b 100644 > --- a/arch/x86/kernel/cpu/resctrl/core.c > +++ b/arch/x86/kernel/cpu/resctrl/core.c > @@ -968,6 +968,9 @@ static __init bool get_rdt_mon_resources(void) > struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; > bool ret = false; > > + if (!cpu_feature_enabled(X86_FEATURE_CQM)) > + return false; Is this missing a check of X86_FEATURE_CQM_LLC also? As I understand resctrl learns from X86_FEATURE_CQM whether the system supports resource monitoring in general. Contrary to what the feature name suggests, there is another step needed to determine which resource(s) support monitoring via CPUID(0xF,0x0).EDX where bit 1 indicates LLC monitoring that needs to be set before the LLC resource-specific monitoring properties can/should be determined. Apart from the checks here I see that cpuid_deps[] accurately reflects the relationship between X86_FEATURE_CQM_LLC and the different LLC monitoring features checked for below. I do not see cpuid_deps[] capturing the relationship between X86_FEATURE_CQM and X86_FEATURE_CQM_LLC though. Could adding it complete the handling of relationships between these leaves? Similarly I think cpuid_deps[] may be missing X86_FEATURE_ABMC's dependency on X86_FEATURE_CQM_LLC. > + > if (rdt_cpu_has(X86_FEATURE_CQM_OCCUP_LLC)) { > resctrl_enable_mon_event(QOS_L3_OCCUP_EVENT_ID, false, 0, NULL); > ret = true; Reinette