From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.18]) (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 B7B1D21C16A for ; Tue, 30 Sep 2025 04:34:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=192.198.163.18 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759206862; cv=fail; b=RgjALxpEUJiq10kFmfQwQFORH7K8uKjvKLhPV5q9vi/Atlm+B5+yFWnteCWR2rcpI/iETTWrKWZIbSZ/ZdyktrexDYkp1Qd6A7i5/BI3RSCJ2ATg3GbB3Hrd32uauG5oyjOhE+Lmtv4BDMYlxlE4OZTP0rxfxdfvDL2v9GrLjdc= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759206862; c=relaxed/simple; bh=qUXi7n3Y7Ei7U0/U0+/MeM/UcILqwBWeSssoKjG7oYE=; h=Message-ID:Date:Subject:To:CC:References:From:In-Reply-To: Content-Type:MIME-Version; b=jueuMG5/yovf8YVkge8hFF5AiNPltrjCx55LlQxsAOEMyAy7yPDdbQQCwf0g0DZQNNxqWOlMJYjgHHooXMWIjUYQqOBJQ9U+CkeoanVk1lJNDMbuj/4HKsPQOpj7RVoaxlDBkKnfR5HT7wcQpB6XOFztTz6KnZx6K+I9GEGkJeE= 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=EBw5BdHe; arc=fail smtp.client-ip=192.198.163.18 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="EBw5BdHe" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1759206861; x=1790742861; h=message-id:date:subject:to:cc:references:from: in-reply-to:content-transfer-encoding:mime-version; bh=qUXi7n3Y7Ei7U0/U0+/MeM/UcILqwBWeSssoKjG7oYE=; b=EBw5BdHeZqnggix8UC7nRNMWczV/A0IbIUdOVS96yuDG2yPndU+oaGyu KCsBpu9ikufk96mZGtprpM3jvv7wg85dejy8yNbOFH5wATbjue7HaxVEw YeBeNNwIlrROKz6q/oZmMs5/cr4I/lZOkGM/LH9405TqJ4Ftnn5QOPxe9 FcM9AxWQ/L67uklcOcsDX9SHclkum9J0qOYetqLvTSdJB2lsgkgAY1Tpw 3gZh/prIeiWmcmn0RobwNIHHymr43yYuQx5gpNZCQk4+kN+pPDwLPNaS9 ogG5iMy8OG5lPtL+Vk0yq3BNMfhyXUpfOioEt60moU0nG3OycC9MdN8L4 w==; X-CSE-ConnectionGUID: Pild/4exQv6E4DP7U9Clqw== X-CSE-MsgGUID: TjGP0+Y5R9OnbmD/HKt1UQ== X-IronPort-AV: E=McAfee;i="6800,10657,11568"; a="60667967" X-IronPort-AV: E=Sophos;i="6.18,303,1751266800"; d="scan'208";a="60667967" Received: from orviesa002.jf.intel.com ([10.64.159.142]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Sep 2025 21:34:20 -0700 X-CSE-ConnectionGUID: T4uBiic3TCGtRySDt8Cf7w== X-CSE-MsgGUID: K3Njv7u8SUiCUmvraBWK3A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.18,303,1751266800"; d="scan'208";a="209125467" Received: from fmsmsx902.amr.corp.intel.com ([10.18.126.91]) by orviesa002.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Sep 2025 21:34:20 -0700 Received: from FMSMSX902.amr.corp.intel.com (10.18.126.91) 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 15.2.2562.27; Mon, 29 Sep 2025 21:34:18 -0700 Received: from fmsedg901.ED.cps.intel.com (10.1.192.143) 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 15.2.2562.27 via Frontend Transport; Mon, 29 Sep 2025 21:34:18 -0700 Received: from CY3PR05CU001.outbound.protection.outlook.com (40.93.201.36) by edgegateway.intel.com (192.55.55.81) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.27; Mon, 29 Sep 2025 21:34:16 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=MgIZ6l1yk4Xd/3x2HveieFF+370x4lNLHZFWzPLlSJOYw9R5p3FZ9eGdrJxif92Kipda9cNkCz7DfYE7KUMTWmLWOEEB8ywRCnCSnzEtp3gWVEKtyqmH01guPBtAhggN2iOXTFH1Xi/2cccM+eVIQ/cUN0ISQLIlnjs5pfchmgCxXKzWCmpcy+uzFugBxZtWINv34ku3bmB3u4OAZT6RW+0AYDb3KjIACNhBmMoLrCjRRAclyvXmlK+Uu52+eEOQTxBPsGdr0NnKs16cGegOuCJgTGMT7635cKqm/1FuCjOy7kIMaLrxaDbxDgCEVjYhHKc7TbcfERapg2fZBYJIgA== 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=/muGG+6xqRnFvVVZyoutcQ5kOuFfg8jqTjmnExHwIJE=; b=NF13mOQCX9swwPknbEpx7V9VgNEiaiMpdf/9bTXqSRX3D31CWHus/ZwiHZaZO+V8S65DjKt8CGo4T7+kQ2h5wFL4LNn6OyWoZQNYjcxYZdZEx4mgUNE5YaVtNi5yiJkwOE1fxzRuSxk7hhvPwMH6Yaeef35kE6tyE+5SQo1s6lRa3XAx+5b7ZL/VRweNzmYy7ectXMcoBO36ocZzQHJHDnYpTW01GT4t10x7VoQY4v8GEU1aTn+c7SUHANhnium46ZndXd8wrCoqaH8ZJbFZf/M9gGdYbs36O/HBVznRihp30MS+HeoCSd6xHYJUtIhB9L8/8Ln97aREZ8Uk3UxhVA== 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 DM4PR11MB6020.namprd11.prod.outlook.com (2603:10b6:8:61::19) by SJ0PR11MB5152.namprd11.prod.outlook.com (2603:10b6:a03:2ae::22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9160.17; Tue, 30 Sep 2025 04:34:15 +0000 Received: from DM4PR11MB6020.namprd11.prod.outlook.com ([fe80::4af6:d44e:b6b0:fdce]) by DM4PR11MB6020.namprd11.prod.outlook.com ([fe80::4af6:d44e:b6b0:fdce%5]) with mapi id 15.20.9160.015; Tue, 30 Sep 2025 04:34:15 +0000 Message-ID: Date: Tue, 30 Sep 2025 12:34:01 +0800 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH v4 06/28] sched: Save the per LLC utilization for better cache aware scheduling To: Peter Zijlstra CC: Ingo Molnar , K Prateek Nayak , "Gautham R . Shenoy" , Vincent Guittot , Juri Lelli , "Dietmar Eggemann" , Steven Rostedt , Ben Segall , Mel Gorman , "Valentin Schneider" , Libo Chen , "Madadi Vineeth Reddy" , Hillf Danton , Shrikanth Hegde , Jianyong Wu , Yangyu Chen , Tingyin Duan , Vern Hao , Len Brown , Tim Chen , Aubrey Li , Zhao Liu , Chen Yu , References: <20250929140920.GN3419281@noisy.programming.kicks-ass.net> Content-Language: en-US From: "Chen, Yu C" In-Reply-To: <20250929140920.GN3419281@noisy.programming.kicks-ass.net> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: KUZPR04CA0023.apcprd04.prod.outlook.com (2603:1096:d10:25::13) To DM4PR11MB6020.namprd11.prod.outlook.com (2603:10b6:8:61::19) 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: DM4PR11MB6020:EE_|SJ0PR11MB5152:EE_ X-MS-Office365-Filtering-Correlation-Id: 83672bd3-95a3-4932-74c6-08ddffda9c47 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|7416014|376014; X-Microsoft-Antispam-Message-Info: =?utf-8?B?TE9vbGZRZ3JkVXVkNWVLVFgrQi9NMkUrQnd3RWhZQ092RXBaKzBhOVNJclJS?= =?utf-8?B?MUNwVktyVmVrMHJGcm5DRndTS2RHd2d3b3NZekNhNEE4c2cvck9PSG1lcS9V?= =?utf-8?B?bmdKclExektYcHp0WFd5RGZNZHVkY2pXYjBVUitaM3VrNEpUb3RKcFRRSE5C?= =?utf-8?B?aGt0K2VzZThKcnNoYW5SNy92bFdHTE43ZXNQRDFTRWgzeFFKcW8vazBLUXJF?= =?utf-8?B?eGt1TXIrSGNjeDZmNURyVG9XN3BNdUs1eTZoS0E5Y2t5UjkzOGl5OXlQWjBq?= =?utf-8?B?aTRmNis2blNZMkw3QXRjaWQ0Q1liR0tDU2pqWGx6Y2Q0NWZCYS9TN1VKTk9n?= =?utf-8?B?eHRWUWs4U3BkcGZET0NFMUhPYndIV1hFTTd4K0hKQ3hDVDF2NlVlWGdaOEhR?= =?utf-8?B?OHJIeS9nMXBNN1Nacmo0KzlwZW5CZi85VXprM2FlMThKbzIyWXNuNGpQVndT?= =?utf-8?B?Y1lGYm1MUHhxam9HdWN4VUsrUlJRTUUvS0crbld4N2dvY05Xbm83b1AxQWJF?= =?utf-8?B?ZElpdDQ2SVZaaHdYNWhpd2VuenFBdUVDeUtHS1BFZ1lTNU4xazJPRTRnaWZB?= =?utf-8?B?cHNmTkdMczMyQ0NZSUozK3VMRS9YTmpNODlaWHRBUFZyY3ZBQnhScjZxM3pT?= =?utf-8?B?RjdXUjZTVVBEd0xlSW03VzM4OHRteStrOE5ucXJHaFB4Q0krdHNCeDZrWVd2?= =?utf-8?B?Uy82ZmdnZUJRSUpQSFRzVHFwcHpFK2toQmszMFE5N1d1M3RuS0VoWnJ6Z1Mx?= =?utf-8?B?RDlOZUtIb2l3M1lENVZZcERuUVdzMnFHcHVGRUZBSHJ1Vm5PNFU1QmZNa2VZ?= =?utf-8?B?Sm4wVVh0YzdRWWVITXpyZVE2Ni83Sm9samNaYW5QdVFYTVhRVGMzcjdlaGx6?= =?utf-8?B?cDV1akZPZ0FIM3N0c3BtV2UwRmZ1Q29VTDhrYU9IMGtxNVBJMWQ0NFkvSFJv?= =?utf-8?B?Z3hzV1JleTBNTXBCdU55T1FqZnVic2tmQ0Fwd3UvODRiMWRwL1Z5Z0ZxRks3?= =?utf-8?B?UUE1cXFPS284M2xnSmk4L3pWK3g5R0JDcy9qMWJOWUpMQXhmSkRKNWNpOFBP?= =?utf-8?B?TlVnZFAyc29OWmNTT2s5QUhwRGtWcVV0Nlk2Qm1WUkR4VXZpVlJ2bUc4S1hl?= =?utf-8?B?MHU3allGRTl1cEFJbTBhNXhObTl3Y3FkT2dkbXhBam5YQ0tzY2NJOUVXeGk3?= =?utf-8?B?am92OHlmbHhXT1J1UDF5TjgwaFl6dGFreEludUNVMWJSL2wyVVpLYm05eWN2?= =?utf-8?B?c1BoaWV0UWdsNzZtSHBjeTVaZlVrTXk1Y2lZYjVPWFppTVJuWUdjSEpmN2hr?= =?utf-8?B?Yjd5ZG52S1Z3R3UwTjJrSDNMTGdFcWtmaUc1OVJiNVJUbkwyVU1HSTdtUlZP?= =?utf-8?B?eUt2ZTBXY1haS3FPLy9aa3lMVGlVeEhaTDI3cHB0S3d5VVlSUVZrd2VuM2xU?= =?utf-8?B?ZytjVjVQSFRmMHV5ZG5ESXQybjVDNk5ERjg3TVlEMktDUHdPaGx5cVorcmVa?= =?utf-8?B?bE15RFpZNUpmWkVjOHNHTjVEWlFkM3YzY1pKekNzWjdBQ1RwdnBodFhLMTFG?= =?utf-8?B?NWFZNFdpcW1xaitSN290OXlJcEd3MGFDVGNuVDhBYitJV1c5T2djZUwzNlRo?= =?utf-8?B?OGhpcm5OdmxIL1FjVzVKQzhQRnRPZEYxczExT3dUVjJqR3RNdVkrNHJKYVFN?= =?utf-8?B?Nlppd2llMjZvK3RWdCtDcThicTdFQlREcU5kdUptYmVBcFZXZUk1TjlLVDhh?= =?utf-8?B?WGgvU0toWmtmdUk4TGYrYjRhY3lLTjZoRHlMc0dYcnlXV0FlRkNQY3VsaDhE?= =?utf-8?B?M2FVdm9Vd1J4d2dsLzdoNWEyRE5Fa0FaalZLMXNzeUtOdDU1b0FnclRwcFVE?= =?utf-8?B?TDhWYjVRdWUvSWVDWktWWFltQUFPcEExZXlvdDVvOFpKOFRzYkY4N3FXSyth?= =?utf-8?Q?rJ4sbB5FKwo0uTb8wu1P4n+8qUyImxJl?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DM4PR11MB6020.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(7416014)(376014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?TFRsVmtNQ0VkWVJYd1ZnM1F5S0dYWHhHcUZiL2RENk9aa3dCenhkY28rbFph?= =?utf-8?B?UEVPSE4wV1BzL3A1dFJtSXpBbXdCZ1J2d3JJT0I2bjBpbnJJcXlrNm05Zy81?= =?utf-8?B?U2tYZDNCSGNhS0FhcXVLazRPOFdHcUJodFhBWU53SzA0eEduUG85Q1ZtbTAy?= =?utf-8?B?L1FqWHFSa1RwNHowUXFlaCt4VHVtU2haT2QySzZXTWNWZjRSSU8vMWdUQzZB?= =?utf-8?B?Z2grV0V5RDFFdkhWQm1tYVBHR2JlOHBvOFBZTTJhdDFIV3BTclRKcWtCYVA1?= =?utf-8?B?R25DTHE3MGlXdE9KUTVSL2d2Tld3YnVsZkJIKzJHM1FXZ1pnU1B3U3RObnhC?= =?utf-8?B?cmZSb0VjUE4wUG1rSnZjdlZaRHMwd253MmFaVmY5d05zckE1Y0JSdngzeE9r?= =?utf-8?B?UWJlVngvNi9hSkI3b2V1clc5NlBCQzdQc20zdm80dmw4K3plWjZNZEd1M0NZ?= =?utf-8?B?YzVSZHBZL2J1azRTVFlHNy85MHdta1hpTWhBL1J5cERuejdSNjIrRFNVbEVP?= =?utf-8?B?R0hEdk9QMFpqYW95V2VtWDdYSVM3SndHcVNvSHYvdmNqZzNBcnFnb25XRWtr?= =?utf-8?B?b3dBa00vV0R0TWcxMWxmeXdmRVo0NHVxMklCTUt4RVJaMi9qRmVyOW1hL1Bl?= =?utf-8?B?Uk9nM29ya0pBUHJvSTE2b0o0cDdCajYwV3Y2R0ZoOXRjQVRaeFVUdnA0UHY4?= =?utf-8?B?aGxlVk1uVmZ1cWVuRkRHcCtXdkJ1UDZTZlUvZzJwTWhXL0NXT1dMcDNWR09T?= =?utf-8?B?aWtGMno3WGd1THFpc3poMGNwdzBDT0xQSWVoQm1ST25vbkxqV1RBaGVtbVFF?= =?utf-8?B?NHE1SmRLQ2lCalZoejNFd3Z0aWcvZE1lQmFTa3ZDbWVWUjRrMGxvdlJyL0h4?= =?utf-8?B?QmdNSCtZZmlJNmdjMjVCekNJcHZGOUcvbGF6b3QyNWZvSGFSMXVqeFpSQWky?= =?utf-8?B?bjVVYUNrZlg3SEVOaEhEQjhaQm9HMXRQbVc5c2N1eHNNWlZsSWdPUVdUMlgr?= =?utf-8?B?L2VzQWRVdW92VC9BS1ZrdFI3aVpxcjN3SVN1enBzWkNNMDN1djV2MHAvc3Bh?= =?utf-8?B?a1J2SThPME1WSEwzeUFBS0FGNzNSaktIQW1CeGZmeUcwS2h0MFY0ekJIWDk5?= =?utf-8?B?SmQvV2xwUzEvQWNkM05JbUNTUXZHemlFL0JQU1paSDNmUWhqc3BVd0Z1YUVO?= =?utf-8?B?cnBRZ1Q4RnhJUGVxQmNvSlhBZ0dnM1VTTFphOVczdG1DcGtxODVjUzdhN2Vw?= =?utf-8?B?Q2xyazhramphSDBKNXVRRUJORk0zM1o1d011TzhDSXVSQ0hlSkpONlJOL0c5?= =?utf-8?B?OWgyWlRHZjVVSExyN3pla3BvaHVUT2hhaUVRQm5hNDdRWWZrZk9hTmtjK3Jz?= =?utf-8?B?SFpOYndOSlRwbnlDelY4SkdkQXZ6VG8yZ1RIVWNZbnlLMzZHZEhOZzM5cytn?= =?utf-8?B?Rm1vdDZyMndrTzZ0NnB6RE4wZEhQVm11Yyt6RlF1LzVUWS9YNVU2Q3ByeVRZ?= =?utf-8?B?dlhxdnFpWXpWS1R2a0V6K3ZQUWNZK3I4c0NXREwvWXNocUFmWmdsRUpLZU5w?= =?utf-8?B?UitRVkY2TzVDSHRFSFBpaWl5QWJybG43TmhpK1VPdlRNcDh0dUVqL1NOVC9y?= =?utf-8?B?TXY4Nk54WXBPbzVQN2FvcG5Ec3dzdk1XVTQ4RU9DU0ZzUlVHdERtVWFWN1lV?= =?utf-8?B?ZjV1SEhDYWRuTnB6RE44czY1ZzBOU2tSL2htbTA3WmtLWkxKQWowN0JRZGJ2?= =?utf-8?B?TUg0ZGFkUkdTTG4zZmlvTm05UXhXVGViOWhOOHQ0NkRIU1plRkxPWlczc1F5?= =?utf-8?B?RDhrQzV6V2huUmk2N2lsQURNUm5xTHpCa1g1NDNTR2lITk9zU2tlYWh4K2hx?= =?utf-8?B?QzZpU3YwUnF0b1R0RXJ0NDFBK2owUWFUNTZEelJRcWt5aDU3VWlIZ1orK0pQ?= =?utf-8?B?NE42cGlGVHllZDZ2ek90aWRBT3UybHJFK3dHTDVvdSt1RFB3TjlQcURLZUhG?= =?utf-8?B?TXhPQkNYYm1HQkZXNVd2RlM2YzNuVVdZUUZtL0llTTFkWUZ5Qzk4K2FjOStK?= =?utf-8?B?NFhOQzBTTnFUNnNMcDVhdFo1WURyeEo1MVpEbzZNODRQZzc3bTRlODhkc1Jj?= =?utf-8?Q?QImaHEkgc4GDXrGgCe6xzS400?= X-MS-Exchange-CrossTenant-Network-Message-Id: 83672bd3-95a3-4932-74c6-08ddffda9c47 X-MS-Exchange-CrossTenant-AuthSource: DM4PR11MB6020.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Sep 2025 04:34:15.0581 (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: KYoH6s3dDItB7ZNXhgBOhtYxfkc/rjnPYItTAuOzaLY4P1BYZcKbYO8z2EPS1Qj9PRfTgzkxNfdbycbduMX0Og== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR11MB5152 X-OriginatorOrg: intel.com On 9/29/2025 10:09 PM, Peter Zijlstra wrote: > On Sat, Aug 09, 2025 at 01:02:54PM +0800, Chen Yu wrote: > >> +#ifdef CONFIG_SCHED_CACHE >> +/* >> + * Save this sched group's statistic for later use: >> + * The task wakeup and load balance can make better >> + * decision based on these statistics. >> + */ >> +static void update_sg_if_llc(struct lb_env *env, struct sg_lb_stats *sgs, >> + struct sched_group *group) >> +{ >> + /* Find the sched domain that spans this group. */ >> + struct sched_domain *sd = env->sd->child; >> + struct sched_domain_shared *sd_share; >> + >> + if (!sched_feat(SCHED_CACHE) || env->idle == CPU_NEWLY_IDLE) >> + return; >> + >> + /* only care the sched domain that spans 1 LLC */ >> + if (!sd || !(sd->flags & SD_SHARE_LLC) || >> + !sd->parent || (sd->parent->flags & SD_SHARE_LLC)) >> + return; > > Did you want to write: > > if (sd != per_cpu(sd_llc)) > return; > > Or something? > Ah right, will do it. >> + sd_share = rcu_dereference(per_cpu(sd_llc_shared, >> + cpumask_first(sched_group_span(group)))); >> + if (!sd_share) >> + return; >> + >> + if (likely(READ_ONCE(sd_share->util_avg) != sgs->group_util)) >> + WRITE_ONCE(sd_share->util_avg, sgs->group_util); > > If you expect it to be different, does that whole load and compare still > matter? > OK, will write to it directly. thanks, Chenyu>> +}