From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from CH1PR05CU001.outbound.protection.outlook.com (mail-northcentralusazon11010004.outbound.protection.outlook.com [52.101.193.4]) (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 DDBC249620 for ; Fri, 10 Oct 2025 16:52:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.193.4 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760115141; cv=fail; b=a0PmWCu/aiLfUMX7NNEK/1E6Qu79HEx6xsy9ThZiEn6id0/IXOXMWScy4ZClojyeBEOSM0pvZCZEEaLf1pk9upae8msnqn/dwJnTQbu+wpUmhw5GtIiDSDHv3EqjiWxdthRpCS7DTJwd1CM+4rOY6AUkGNWA1QV1TuHW3cfJTRw= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760115141; c=relaxed/simple; bh=YI/ft9EDTdlSTbQUqYUsYMFIA62YoQKxbYSZKKgSxj0=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=VzHQbErBqIuQ8R6t/rZo1daoAS6eBpd1/3GajPw2eFi6AbDmZ50qVZlozdoSPako/V6pvHgJ3aLst3PvBMlcBY9fIR2YWmMWGDrnJOst4diPzThBgUn+4pOIeMwKlCoPjbjOEOyUhH43PqoItwqZHxG1ZA0KwY5fRLUBaPHfzOQ= 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=UdliAmTy; arc=fail smtp.client-ip=52.101.193.4 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="UdliAmTy" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=Ilrd54lA0rApYN9f2JFawWJKLYYC/U26BbgbMnLm56301mYe/LxRjH/fcXOFXCEM7nFYcE1SnypVIktclUN6tPR9PxeDYWhbhc5mZ+KJUw1sVXvCFLvU6nFdhDpzSZ+LWhMiMSEQHIwYyxPqdADV0hRCqTwuDfwH6iio93GYI4GDuZb5BqnzY5RB8J4KzWZNJjMQnSkzp6hVs00hGIfdMFskppG8rNor1X1TdsJsTbFSp9O45Vz7ic5QeDar4Wt2b9DYiEEiw/Gs75fo9+8TqJmEEeBZ0uo0RVtcDsrw9c1S8JsueRCsr0Ks8xxA7MREgXFOUmcRXMlnUapQD1AOHw== 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=gMrnPz1Br0RY7FCDtIoFnrwHf1Jym5iq44VTDEoK5Co=; b=dn7DciBCpsbZCxMM+OcMlMU1XIL1MPM/tg4FRi3z3ro7c6F5kbeNUhFVi0dfPC5zCJQk4grG1ka9Ghs0VWG7tFRSW5vqjUaVHCyBpl8yUhiJtVs6VOGXvbNJJbnMjVqKlgw1G54EZCnQAkkRSlxd6qmV4SogsWWNCSWOqEijb5TrIYmEOBA+Tez7SHQWu8WDhmFK2Rt4ndUk+RaNVJS9lsFqwtj5ZU/ROnc0aQctdvaBvh4gY2poOElye3ymyEYnwZpkRxiEEaTIqp5aGv65p2Dgu+aLBi9pQhUaV2mFyaLZuvTMleXFjaC+5qmhsaHmKdbw+bMxJvp/71+OPzbALQ== 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=gMrnPz1Br0RY7FCDtIoFnrwHf1Jym5iq44VTDEoK5Co=; b=UdliAmTynkuUZBd9Bq1z+cvyJMhYG7DE3JyNkkL+yi823XhoVnLDgCU6K1qkwOU+YXUl7kqbaFqQmN27TZeAAsXSgxoCgTvh2E9f5NamqGEz607n2C3L3f8U+/Th1WUEqhPm9xvMkgXxvoj/dus/tXhNwMHd/4eTM3uESa8cBoA= 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 DM4PR12MB6134.namprd12.prod.outlook.com (2603:10b6:8:ad::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9203.10; Fri, 10 Oct 2025 16:52:16 +0000 Received: from IA0PPF9A76BB3A6.namprd12.prod.outlook.com ([fe80::8d61:56ca:a8ea:b2eb]) by IA0PPF9A76BB3A6.namprd12.prod.outlook.com ([fe80::8d61:56ca:a8ea:b2eb%8]) with mapi id 15.20.9115.018; Fri, 10 Oct 2025 16:52:16 +0000 Message-ID: Date: Fri, 10 Oct 2025 11:52:12 -0500 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3] x86/resctrl: Fix miscount of bandwidth event when reactivating previously Unavailable RMID To: Reinette Chatre , Babu Moger , tony.luck@intel.com, Dave.Martin@arm.com, james.morse@arm.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com Cc: x86@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, peternewman@google.com, eranian@google.com, gautham.shenoy@amd.com References: <8eace6e47bb7e124ffb6c10150d1b7d38c2f5494.1760034251.git.babu.moger@amd.com> <3c428de8-f8a6-47a1-a5ca-768d1906ed24@intel.com> Content-Language: en-US From: "Moger, Babu" In-Reply-To: <3c428de8-f8a6-47a1-a5ca-768d1906ed24@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SN7P220CA0016.NAMP220.PROD.OUTLOOK.COM (2603:10b6:806:123::21) 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_|DM4PR12MB6134:EE_ X-MS-Office365-Filtering-Correlation-Id: 54ddd507-3f3b-45d2-505f-08de081d5e0f X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|1800799024|366016; X-Microsoft-Antispam-Message-Info: =?utf-8?B?bDgycHRFSkVzY0N4NWUvOW02ZDR2SkpZWmxNQ3BvT0QwY0xOVHZKMEpXOXA4?= =?utf-8?B?MUlHTXppeVBPR01tdXdvc2l0anplcUlEai9acDhjMEJCdndMUHFNLzNBNnM1?= =?utf-8?B?dFk5Ulp3Q25sZ0JIeG5PSjVTamlzWU5VUjJuRzhUMjNXbGpxdlIwRURWckIw?= =?utf-8?B?cjdiTmxicnJQM0V3TXZTeUZTaDdFcTdnQ0svSEZBSUxuUHd2Tjhuc1g1VFlB?= =?utf-8?B?T2JiTXRuS1IxTURuNFVaWWJFdnBJWk1ZZGQ1emlVMmhpbkpIM2E5bE1nTms0?= =?utf-8?B?T0pET1gzb05BNk5GREFIbW13WDNVa3h6ZUNYcGs3ZTdHN2tETTZ1dnloWFFN?= =?utf-8?B?V3RTVTVmeS9Zck53b0lWdEF0WHhGeFR4cVlNcENVVDJvb1NwOU5nWWQrVGNx?= =?utf-8?B?V1V1Y3c5WG0yN1hSdU1RbVV2am1XcTRaM3VHU0ZhOVdreDc0aEY2SDNuZ3pp?= =?utf-8?B?NVVCU2JjdUtZL3VLcG9kRDRtSjlCVXhpc1dWY2w3Tkt1YVIvTlkvaG5SdTBa?= =?utf-8?B?Q2xpVWFiRjMyK2YyM0FPeHRobmdsWnBWc3VqQi91LzNqZ00vNlVlODN0a1Zl?= =?utf-8?B?K05sRDdVOEFFUFN5a3ZvYWM0K3UrRUlma1lVckpkd3hyZ0tvZXpMTUhCKzA3?= =?utf-8?B?ZlVoMjQwQ1FzdkFBdm52V2hNWVQrdjh5ZEZFcUk3UVR5bW05VmRVWTJFZ0E4?= =?utf-8?B?cTU3RzB3cXl4blNVcDRmZERRUHJYRmpLVlcxWFJoWlp6Lzc3WnRTQktIemxj?= =?utf-8?B?TGVPdDVPY1lFYkM0eG9tekRjcC9GYklQTDBrQk8vV2o2RDRYOXhLSURBWFB6?= =?utf-8?B?eFJkalZWcDlEL1V0azIwc2h4THI3WUpndmdUVlZJQUlqUzZwbkNHQ3I3K2d6?= =?utf-8?B?WlYwdmxZRHVteUNaVWZkVjFwZWdrTVJ0a3dKclZDTTNRQUR4bFhMRlVkS09W?= =?utf-8?B?L1NRMXNOUUpScE5RakZ4akt0ODcrSS9pYzc2Vml6allEUEtXV0JzQmQ1aVJj?= =?utf-8?B?RnFoejBNVkFiVDEvdHZSMXUwZmZJbGFyc3BsQ2gxMWJRbFBBTkNZYWxDcDNT?= =?utf-8?B?OTh0d3ZpcDl1WnhFT3ZUdVlzcnFpWFY4SDkyN0VKVFErRjJNK1Rvd0cyVVZo?= =?utf-8?B?S2hvcklCMUJZckpQaGRQbS9MbnFpUjRhNXNuYXdEQVZMVzhxWHltaG5IUU8x?= =?utf-8?B?VFc2a1R3MTk2N2xHSHlaY0VaME1naVAyaHFSNDE2ZnlVZ2Z0dmRuU0o5bG1W?= =?utf-8?B?ZURiNzN0OVA5Njd3T0dVaDFBYXVneE5lN215SVZ4NkxQWVRld1FWMFNwN243?= =?utf-8?B?SlpsWU9sbGlNZ0swUEZLWjZvVUdxdktlREFUWG5WdE9uam5Ba2J4YUt1OXVj?= =?utf-8?B?OXc3WHhOemtzK2JpU21ZVmZ3RnVwRGd3ZGw3MlZxVHhySXNIQ0U0eXFDVzc3?= =?utf-8?B?c1VucUpDN0pUT0pBQ2VzY1VibVNjNzR0cW1UM3YxQ2Qrc3FZN2V1a2J6RmdW?= =?utf-8?B?K1QzVXJ0aDQycWx6YzNpcjFNdXhXOGF2TDVuZGs0emljU09raFN6ZVZ2NS9n?= =?utf-8?B?OFVzOHplanYyNytBTTFKbG9qdHNHb2RyVHdXQnZrOTUwdEloZmc4TzJteXh0?= =?utf-8?B?Q2xiRnBDS0t1NUFITzFkcHVqUllQNWRlSVFGRTQ3VklnVS9LVGR2clkyZFI1?= =?utf-8?B?d2hzYmdZcEdVTTNLTkhjSG9zWGFPQ2tCSFJjN1B2aUJiUmkxd01OcGo2akto?= =?utf-8?B?eVhGbUZrMWhYYXVaalczWmsrRlRmL2VjQ1h1LzBEVkZQRldrWnU5SFQ1T1Ru?= =?utf-8?B?cDFrWWtMeE0xWjByd01xTXF2STErcUJ0Z0syS0lrei94M3RMdnk1a2lCOXUy?= =?utf-8?B?YTFOQ2xGU3lvMy9kdHQ0MDRLNzlKdGI3WXJwOHRWdGV2cmRyRFhqNUxKMldB?= =?utf-8?Q?/QnpYu2maGHFY388dDywIIMkD1qSruuB?= 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)(7416014)(376014)(1800799024)(366016);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?TWorQ25STzNMbDJ1bUEwbFJwS0xNT01WQXlpN1pCRktCd3hoT05NVjEzWi9N?= =?utf-8?B?aEVuMW54ZS9IeWQ4T1RwaDErUTNaYklqZEZwTC83TXNIc3JzZ2NnNU5XSnVZ?= =?utf-8?B?MjFwSnZqSE5vM3BaR2UwUEhCam5UZVkzMVpvTWQxemRwWnJQZ1c3aDFQc2Rh?= =?utf-8?B?b1NBMG9NeUxlQWU3dnFxbm5OcGM1cEtNdjFOR3ViMyt5TDJncHFtdmh2Q1NZ?= =?utf-8?B?elJ5Y05vOThmMllaOUFtTmdJOThHU1htbU9JelVOb3ZmR1pQcG1wMldXcnAy?= =?utf-8?B?SjNxMk9vWjNxMEwvcVU0dFVWUm5qMXE3Y040eEdZaXphdGRGN3VtZ1pxbXpK?= =?utf-8?B?bHFhbWxLTkFqTlBtOWQwTlF2eU01YUVUNXAwcGxPcHRISTJJaVlQdTNCclVa?= =?utf-8?B?SUlJU1FPY2ZXWTZtc3Q2R2VyVDdVeG8zTGJiYzdRMzl5d0lkN2sreHBBQ0hr?= =?utf-8?B?d21JaGsxMldJWldNT1l3YlY3R2g4aGttYk9CMmcyQXlVOG9VYVpkSFgyRmp0?= =?utf-8?B?YmxvQ0V2RmZ0enRBY0ZJa3lCVkZJY0FZOFJxNlB6N0ZwOElzb3ZKNEJmTVVJ?= =?utf-8?B?NVpPYURtbTFoT2dzOXlFaC8rbEVDV1F0d25sRFkrM3RBOWN3WGIvUFJXNTZS?= =?utf-8?B?UVd4aGdjaFNOWFR3ck1HaDFjaVU3NUozVnB1ZnhGNFNJR1Q3V0ZiVTlhM09a?= =?utf-8?B?VEpNMm9pZVZaWWdPRTdCNkJnNlVTNngza1AxeHBzSjUzUk9hRDVWWTN6cWQr?= =?utf-8?B?ejUxMlNQdy92cmsxck9MUEZZYklFUmxNM3huRjIzMnptKzZlM2g0UWhLSGJ3?= =?utf-8?B?WmtDSERRVTZpYXRmdlpMbWlIb3dHd3UyeDBlSzlQVEhmRytzb0NrUmlRZlE2?= =?utf-8?B?SExDRFJhSFVPYVcvRmV2SXp1dkpXNW12Sno4ZTlNUWx0QlF0SEFIQ0Z5TGZq?= =?utf-8?B?V2RXMCtodTgyeFhhYkFDV0JYM0lUeno1M3YwZXpGS043ZnRteEo4emFwS1F1?= =?utf-8?B?UlVxWEFwRjVLVnY4cU9LanBYdzYzMUhVWWlnbG5UTm94MlhGSFd4Y2JqbHhF?= =?utf-8?B?WnJtdjNTdDBlakVKaHVxQjRzK28wOEtxWm90Zm55ZU5vdlllUjhYZFh6cEhm?= =?utf-8?B?NU9FSDlKZGpnTnZXdmFwenhxbTdhQUFRa2REMmQzYmlmS0ZteVpCSjA5RkFG?= =?utf-8?B?ZmpiQzFlekNJdUM2b1N3d2oyRE9aRzNIRU9JdTdtQ2pxWW1WRFNtUEY4RlMv?= =?utf-8?B?ZHo2dzhqUHIvNlZPUnhrR1RWUzgxMWorSTZTS3NnK0JlMCsrQ1JBK3JlSStn?= =?utf-8?B?YUJ3dk9pLzJ4NENFSmk5cE9MM2VpMVVUZlpxVHZyK1lTZHcrZDd6ZnM4RU5l?= =?utf-8?B?STduMDlDNndUT1BQa1BhUUhJSzFpM3J2ZGliWlpVZWwyUmoxc0FIL2NCQjF6?= =?utf-8?B?YXZGSDVpV3h5WkVnYlVKaXNQdDZaN0F0S2dqenBSNDNERGRkUUNFTWxSbHg4?= =?utf-8?B?My9XNnNuSDBub3ZzbTdQR1pzdi9GS0hXSyt2NVlITWNZeWlac0Vkdkt5cXdI?= =?utf-8?B?d0RnRzRrZ2pXZFRNOXhBSVRZTW0vR3hGR09MWE81QTRXNWJLU0w2NHU5dGQw?= =?utf-8?B?bTAra2xlUi9yZ05TU3g0N29TSTg3WGtGWk9Gc1U0T1lPTUFFcmtjNTFvL3g1?= =?utf-8?B?VTFwWXRnVHdVUVY1WEluWkZRZktNRHNMN1gzZ1lramJGQ3cvY0xuY3QwUUdy?= =?utf-8?B?azJwRlhEdGIyYnFBTVhHRjJsSmE4K204d2hkdDV3UXRxYUtkaDMzZzFzUG56?= =?utf-8?B?blM0cnRQS2FLamVLUVFHeWhpZmVzVXlOK1o5VXpibWcrYWlNeVZaT09iV3Bs?= =?utf-8?B?ZkN0QU1UWGlRWE9JRG1MRXQ0MERHT0hvdzdZajJJdFJ1ZTU3K2NxT2d0TG5J?= =?utf-8?B?V1A1YVVWcXRrdG03bGtOb1lVTVVJQkJHRTV2aVJ6bVpZMTh6eXFrYzFzdFpW?= =?utf-8?B?UGMxbFJHT0U2YVlTMVhLM1hyR0R5TXlGUHJyYnFHcTc0eFROOFFYUlpZTmEy?= =?utf-8?B?andVN0theXBBKzR4N25BSzFjSGdzaWMwWktkSzJlNGd3UjdyV0lGcWwwOXJl?= =?utf-8?Q?oGHEnOxl39hgDv2muzgV2OGTo?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 54ddd507-3f3b-45d2-505f-08de081d5e0f X-MS-Exchange-CrossTenant-AuthSource: IA0PPF9A76BB3A6.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Oct 2025 16:52:16.0872 (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: s/Q7dWIt+2h3+gfEKhJTfLKk07e+7YtPRR7AurggeaoJoPN2TG1LQqH1di7mwLlJ X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB6134 Hi Reinette, On 10/9/2025 11:19 PM, Reinette Chatre wrote: > Hi Babu, > > On 10/9/25 11:29 AM, Babu Moger wrote: >> Users can create as many monitoring groups as the number of RMIDs supported >> by the hardware. However, on AMD systems, only a limited number of RMIDs >> are guaranteed to be actively tracked by the hardware. RMIDs that exceed >> this limit are placed in an "Unavailable" state. When a bandwidth counter >> is read for such an RMID, the hardware sets MSR_IA32_QM_CTR.Unavailable >> (bit 62). When such an RMID starts being tracked again the hardware counter >> is reset to zero. MSR_IA32_QM_CTR.Unavailable remains set on first read >> after tracking re-starts and is clear on all subsequent reads as long as >> the RMID is tracked. >> >> resctrl miscounts the bandwidth events after an RMID transitions from the >> "Unavailable" state back to being tracked. This happens because when the >> hardware starts counting again after resetting the counter to zero, resctrl >> in turn compares the new count against the counter value stored from the >> previous time the RMID was tracked. This results in resctrl computing an >> event value that is either undercounting (when new counter is more than >> stored counter) or a mistaken overflow (when new counter is less than > > Since there is going to be a respin ... there is a stray tab above. > Yes. Thanks -Babu