From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from DB3PR0202CU003.outbound.protection.outlook.com (mail-northeuropeazon11010040.outbound.protection.outlook.com [52.101.84.40]) (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 D2A6B364038; Fri, 9 Jan 2026 17:13:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.84.40 ARC-Seal:i=3; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767978811; cv=fail; b=gM5ggeeAQFj3vSIwmX2VgUGGSx+YdsC54plOyikPekpEoIPgDHngbFjO2QzAhrPYPcHze/KWGyj6oSJcv531rr2XsD9wS7ZbS/8kmTlf/lQc2UJ3vU8LRccE356vLeWvKE+7OA1ZuWZMNgd00/DrYrxIQa5/d+o2e/P3+/jbSVk= ARC-Message-Signature:i=3; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767978811; c=relaxed/simple; bh=+e6oQOvE0wyGDboyXcGZ0NQLDq9CGwW3bKDGOGiwSDI=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=nwH72J8IDXVXGemNtFOmJuqwMzC1GWdwJILVgMbjgmBocyxDJdDFwawSzDDzcanOF01JhLM7Z16CbN9FhXTwRCUkRSd6vy0Rdf7LTpWIxpDR4CXeOjfum0Lhmf/sgIZuhZEI0nF/mA1rHcPfMeBNaYur0EN6eKwQ04TE4HI6wF8= ARC-Authentication-Results:i=3; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=nre3ymdm; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=nre3ymdm; arc=fail smtp.client-ip=52.101.84.40 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="nre3ymdm"; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="nre3ymdm" ARC-Seal: i=2; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=pass; b=KDZ7R9Cq5XeR/dbiZhjaIGLlOyHDPmkND4ldY1G7tj8WE7TBRuK8GjNGEzv/ZRlWtBp4Bg4d3nM6aqlm3q+KZ36RGLqN6xDoLyNdXDvijpEcH2geYgSOXfcOTiyKazbAmH+Njxv9CNFQEdEH2x2ldMvlMvxDI9JdT3PVAJdgEyMirf9AVf+Okepfz72UnUpujFN7ulAo9S/LuhKtQfOELuphtqwryIgYN4RRrhm2WI6cyB2fS9aQBii4p/y+G6YTcQZ8ZEToaDT5xZwwotiTeVKfwTcAcb2scWGlavnBeCjJu5ioOZvne8trrweA10NmnoKYo4PrYODVTyUHjlFSDQ== ARC-Message-Signature: i=2; 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=hM0ttMoGgr5J66IY0UmbJ/iLgvPVS2FsG/AmMZ+1xnY=; b=w1MwDfmMeyT9TFehhpEZMJv5z0o60EPbbSCHnQ6Vg4cAkDT+1qGYJYz37wu0ToKR0tLE1d5SoAc6nYltNR329wTY/jxYj+j6ZJijlEPnlFuuGtKN/JGh7mmdBPoO018NwWq1+0F+WH7MSzeqebxCbrpBXRmBma70445IzDs2Cl+Snoaa56+I0tocoK7DFxkuzZfc/RcS9QGwMzVjY4H8fiAxV8eKEOyoMmF5BEZnNBWkEwws6XnvrEATzkjArXjWYGxc8UoDoIEX7j4Lq28QgAil31pEm1qnHyDjhzqcFtjXC16OBb0aWrE/KmNRYEXncmYHBCF3AkxMgZKqGcd98A== ARC-Authentication-Results: i=2; mx.microsoft.com 1; spf=pass (sender ip is 4.158.2.129) smtp.rcpttodomain=vger.kernel.org smtp.mailfrom=arm.com; dmarc=pass (p=none sp=none pct=100) action=none header.from=arm.com; dkim=pass (signature was verified) header.d=arm.com; arc=pass (0 oda=1 ltdi=1 spf=[1,1,smtp.mailfrom=arm.com] dkim=[1,1,header.d=arm.com] dmarc=[1,1,header.from=arm.com]) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arm.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=hM0ttMoGgr5J66IY0UmbJ/iLgvPVS2FsG/AmMZ+1xnY=; b=nre3ymdmzEjpYhOaGX0/93H7LPbRc2/a2pbMbR0+LPfj+7vn1RJX2tySP6FmAupjhfSZVITtJCx0ew0iwD6HJmi+BVt4cpqSRAbat13+SjENQLP+lWRUKJ2ibSPbUJ1OULNePLgOkdULJ40PTK+b1vcgcRNIyPu+RIS+WlfcOTI= Received: from DU2PR04CA0288.eurprd04.prod.outlook.com (2603:10a6:10:28c::23) by AM9PR08MB6019.eurprd08.prod.outlook.com (2603:10a6:20b:2da::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9499.2; Fri, 9 Jan 2026 17:13:23 +0000 Received: from DB1PEPF00039232.eurprd03.prod.outlook.com (2603:10a6:10:28c:cafe::5d) by DU2PR04CA0288.outlook.office365.com (2603:10a6:10:28c::23) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.9478.4 via Frontend Transport; Fri, 9 Jan 2026 17:12:43 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 4.158.2.129) smtp.mailfrom=arm.com; dkim=pass (signature was verified) header.d=arm.com;dmarc=pass action=none header.from=arm.com; Received-SPF: Pass (protection.outlook.com: domain of arm.com designates 4.158.2.129 as permitted sender) receiver=protection.outlook.com; client-ip=4.158.2.129; helo=outbound-uk1.az.dlp.m.darktrace.com; pr=C Received: from outbound-uk1.az.dlp.m.darktrace.com (4.158.2.129) by DB1PEPF00039232.mail.protection.outlook.com (10.167.8.105) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.9520.1 via Frontend Transport; Fri, 9 Jan 2026 17:13:22 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=d4vsiK0QhDe9C3UlLHAra7G01evdWstR+aDavpX2AZuLE52+0H4ssLN5xwSb3+IkShTvL2/cGiX6fEwVv7z00lcQQulM29aT4RHJ6zC31gOX9LD3EbpiJkLCU2uIVokw9r7HMsyg5EiNb2CTNDWq6ozsZcdjulXJ+CExy+g40XjzAnpE2v59XIs4Jrow3RrpV3A0cTaOgncTGNChcwM74vbHQ8TXM3bxo/U8/qDWVs91RiFPFT9Mt/42waYwneB2RkwZHfc03LNgWH4Vo1tGmHwYUl8N8dZhqISOyYvLv4N0wMZyM/CpqeOBSJFDs8K99CBPghDjLKhkSEpmDUbFIg== 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=hM0ttMoGgr5J66IY0UmbJ/iLgvPVS2FsG/AmMZ+1xnY=; b=m9KuNCo46MHy2Mi9PKnT0cEOPztFQL3it43rzxUO020Ivq1aYRU5oLDcvuD0CHgVhn2yNn2U6S7r1zuE3YFK7Pq6Zwpo4+q9ou0VDcFiDHF3ZDQYOgoDQscVa+1NDPkvk7dFKYEqmXT8t/8SsLWLnaqjFAaERvdxrwzdI9v5PSr+dvqs2FHdAxeqFeVpr5FpbxiN8yn/rSamrfIIBdjlEcMXBEA/LWthNkKjLyuVbrJrDkgwLKNKB/b3CvOJcO+GeiAxgZZx+Du9E4o8Nhc0ntYAEvhjnjMMfdgbtuNWOfi3/c/GfFO0Pok4xgeQUAfvO1eN5FSnYRJyxVXlO3IZjw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=arm.com; dmarc=pass action=none header.from=arm.com; dkim=pass header.d=arm.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arm.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=hM0ttMoGgr5J66IY0UmbJ/iLgvPVS2FsG/AmMZ+1xnY=; b=nre3ymdmzEjpYhOaGX0/93H7LPbRc2/a2pbMbR0+LPfj+7vn1RJX2tySP6FmAupjhfSZVITtJCx0ew0iwD6HJmi+BVt4cpqSRAbat13+SjENQLP+lWRUKJ2ibSPbUJ1OULNePLgOkdULJ40PTK+b1vcgcRNIyPu+RIS+WlfcOTI= Authentication-Results-Original: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=arm.com; Received: from VI0PR08MB10391.eurprd08.prod.outlook.com (2603:10a6:800:20c::6) by AS8PR08MB6646.eurprd08.prod.outlook.com (2603:10a6:20b:350::15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9499.2; Fri, 9 Jan 2026 17:12:19 +0000 Received: from VI0PR08MB10391.eurprd08.prod.outlook.com ([fe80::fa6b:9ba8:5c2f:ac91]) by VI0PR08MB10391.eurprd08.prod.outlook.com ([fe80::fa6b:9ba8:5c2f:ac91%4]) with mapi id 15.20.9499.002; Fri, 9 Jan 2026 17:12:19 +0000 Message-ID: Date: Fri, 9 Jan 2026 18:12:18 +0100 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/1] sched: Ignore overutilized by lone task on max-cap CPU To: Christian Loehle , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com Cc: rafael@kernel.org, qyousef@layalina.io, peterz@infradead.org, qperret@google.com, sven@svenpeter.dev References: <20251230093037.427141-1-christian.loehle@arm.com> Content-Language: en-US From: Pierre Gondois In-Reply-To: <20251230093037.427141-1-christian.loehle@arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: PR1P264CA0069.FRAP264.PROD.OUTLOOK.COM (2603:10a6:102:2cc::7) To VI0PR08MB10391.eurprd08.prod.outlook.com (2603:10a6:800:20c::6) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-TrafficTypeDiagnostic: VI0PR08MB10391:EE_|AS8PR08MB6646:EE_|DB1PEPF00039232:EE_|AM9PR08MB6019:EE_ X-MS-Office365-Filtering-Correlation-Id: 49c05e37-d0f8-46af-42ab-08de4fa264c2 x-checkrecipientrouted: true NoDisclaimer: true X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam-Untrusted: BCL:0;ARA:13230040|366016|376014|10070799003|1800799024; X-Microsoft-Antispam-Message-Info-Original: =?utf-8?B?eFBrcklpc2llYk1lTWhRQWFmT3ozTVFFdlAwNzFuTUd6Smc1K0xCa3N0ekxw?= =?utf-8?B?Y0w4MXBBMWFhSXdQSGdnTzhpZ3RNWE9JOVJKNXFIQldrWlY2M0k4YVYxZVh2?= =?utf-8?B?SWZhRzVlR3h2QWt4NElORUMzckRGbUtkRUNDT0U2OTB6WWcrQ21XRDhqdmFl?= =?utf-8?B?YXI0cWllcW1CdktmQW1rUlZSa2s3Z2pBVWZRQlcrNlRuZVJFWHhrWFM5ak9Q?= =?utf-8?B?S0ZCUmNlcDRybDJHblNrSTYxQTk5VllYK2NUYWMwa0lIb1lsbEFuanlZb3Mr?= =?utf-8?B?RlBJQlBBODNob1RTa1hsdjFRandHek5FRzVWRFdqN0NvYnpoUndRRkRvZWdu?= =?utf-8?B?blI4cG0xWXpnVXpqR3JMOGRZaUYzZzg3N1RJN2N1Mmp3K1NNUy9IQUJuUEdp?= =?utf-8?B?cU5sU1g4SW5hMW1iVmg4NUlDTXdMa1Y2aGVwKzJxcG55Z3dCUm44V05YbC9h?= =?utf-8?B?ckF0WEJKVVk0dFZQVFAvYTJSODdpaGVYYXlEUlFUWFJQNjJocjE4bkd4YnJs?= =?utf-8?B?ZUlMak5QWHc0WDZlcmUyMzlSemxzdi80eERYMHo4WFU0UEFOWGRWL2g3UnpJ?= =?utf-8?B?M01qTE56Q3VxUFlGbGk5NVdpZ011WlAvWE1uOEl3Z2RQMVZrTnhwVSszS3pz?= =?utf-8?B?WnJxSk5vclVuVk9ZUXJnUUZReEZ0KzB6U1JEN1RDRVFEbkFIZkZUNDhYbW9T?= =?utf-8?B?SFhacHo4UEZuR3VDbzN0RlQyb0hHb2JhaEQ4cEhkL3hQdXlpN3dkZGpkS3Mz?= =?utf-8?B?S04rLzhZMWRRRlJnQ1pjTzJVT1Q3dkt0NGZ3V0RHZng1bUtZM3paaGI0M3FW?= =?utf-8?B?RFVxcjNMeXVRbjNLaTlxRjUvQjJJUlhwTm9wSSt6U0dlSkV3QjlCSnNOcTRL?= =?utf-8?B?N2ZGUXJzQTM2Ni9BNHpjTWNLL2dYYjNwL0swUVhmOHJyZGw1eG9MY0MzVXRO?= =?utf-8?B?aVd0azZKUEdHRUxDTVVpcTQvSVpMeXA4WWl4V29sQ2hRVnJJb3p4WmxWblJS?= =?utf-8?B?L0FCSndHNDYydlY3UkpnSWxGbU9SRFdRdVBVRHIxRldHaDFFUE5sTnNzektT?= =?utf-8?B?YTRnMDlmRTNjVmJYeUNRak4rdDZzckdaM25YVnJnbHhvb24rTzFFN3ZWNjlu?= =?utf-8?B?bDVhUlJ2T09oLzE4STkxU2J6NWVWZ0RXdXBlcmRYQlNKWnFjOGFYK28zNG0r?= =?utf-8?B?ZTZWY2sya2k2ZTVrNnhmMkxWTyswOFpjdXVSckpRdmViWEJUdHZQbjJKNTNn?= =?utf-8?B?WFNiVVprVllwL0tXSE9LZkVXbFZnSjJpN0EvL29PdHJjMTI3WFBBckpuWlBz?= =?utf-8?B?bno5TjA3dXpuOSs1MENGenYrVmc2R1VpaksrWVFzK0lENDlOWHd1SGJ2akg4?= =?utf-8?B?dzZpSDZmNFFDalJnUGdWeTJCMjdrMUMrT3hOUVYxOTkwODUzYXlQWXRCWkFm?= =?utf-8?B?UUIvQmwrcEhucGl4MEtEZ0pQbTVSVU1XbllsV2lWMFlZaWVhZ2ZjYXJFeXNV?= =?utf-8?B?TWtTcTAvV3d3OU5TQ3pUZThWcEVtdkl4OXdXTGJmNGo3N3VGMEpPNm5aMy9o?= =?utf-8?B?amNsbTV4YUJzdk9WYTdTYzk0eVZNLyt4aHpYV0JCVjVhSVVkZlUxcGcvOXAz?= =?utf-8?B?MUxoUTFNOHhoYlBld0ZXaUNsY0VjMEF5UFdBV1N2YjZnZ2hhVnFyalJRd2NL?= =?utf-8?B?UnNKY1NIdDVLaWkwT0pLQnRNQ3RRVWtFQ29ibDBHNEdYOTYzRkpOeUFhSmlW?= =?utf-8?B?MUNvTFpHOEI2ZXFLSWNLdXdxdzFNbGp5elZ4NDBGM1hqalZPblppVTJzU21M?= =?utf-8?B?Mk5BdlprUDVxYUJYTjRneUx5cGxFQlF6Q3p1SEd3WTN3VWJCM2E3M1ZvKzJo?= =?utf-8?B?RGhPUnFNRlB2ZlE5M0Q0WXBCckRXRnVhbGtHb1diMEZmRmo5ZjJCQ1dVbnhq?= =?utf-8?B?S0s5RUlhUTl5Zk51c1E1S1BQM0lEU05hMmxGanMwSlF0YldkRnozL1I0MU5P?= =?utf-8?B?UDdGeW0xZ25BPT0=?= X-Forefront-Antispam-Report-Untrusted: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:VI0PR08MB10391.eurprd08.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(376014)(10070799003)(1800799024);DIR:OUT;SFP:1101; X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS8PR08MB6646 X-EOPAttributedMessage: 0 X-MS-Exchange-Transport-CrossTenantHeadersStripped: DB1PEPF00039232.eurprd03.prod.outlook.com X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id-Prvs: 391620ce-fde4-4977-5b76-08de4fa23f13 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|35042699022|14060799003|376014|82310400026|36860700013; X-Microsoft-Antispam-Message-Info: =?utf-8?B?eEQwMmNRYlRlZFRHN08xRlVVdVBKTzB3WXdPQ1l2Wkl2eUt6NWxZOGtGWUVT?= =?utf-8?B?UGJkTy90WkpBendZMjdSZG9vWVJFenVNeElKbWsva2ZWUGRFa0U0c3pPSFNR?= =?utf-8?B?TUk2V2t1R3g2VVVPYXYyeWV6bExIRkRpdS9KQk0rSU5JYmlhMlhUd0VEWkpv?= =?utf-8?B?SDk5bGR3Uk9OOHFaWFJNQ1NYTTFacjVYdG54ejRydjdqdTBjQWM4RFkxS096?= =?utf-8?B?OHdPT0RQYVZEZmtRYjFzaVBuUWR6VG1MRCs0RU5Pd1RJL1FkNlA0OEN3eUJT?= =?utf-8?B?bUtad3FPUEVrRnF1VTJqWmp3NEFjTndGaktvWE15blN1ZjFwcldBMFpjN0xh?= =?utf-8?B?akgvOHRRQWZzOGJhenlJMFRGTmJOdzk0TVlBN3dvSmhFcENrMTJabGQ3ejVs?= =?utf-8?B?TXRqN3J2ZlUxS25TUklYeklTYlFCWmVSQlhYYkdna2hLOTFKTmpJK3JEcVFm?= =?utf-8?B?UVN0TmpJN0ptOU9OdDRxY3RwK1Vld0ZTUGtVWEluNFdZcXZ3VEdWdWJ4bnZJ?= =?utf-8?B?c05oNEtyNzlCSklidmFlYlRkSEVTNW5ONTdKNzEwYzVBd3U4L05sZjBnNm5W?= =?utf-8?B?Zkh1Y1lRWlNFNkNJS091UGkrVnlNN3NjTDBVUDVFcGN6ZmxpRnRRaGltczJh?= =?utf-8?B?cFhmby9ZdDB1WHI2ZFhXVWNpa3lIVnBFNFVsTmlSU0ludTd5NHNqUkplRHkr?= =?utf-8?B?Y2hidHZGajNvK3JrZ2F1MWRNNEZ5NzRLd3FYNHl4dFkyWmJLNHNmTVVXd3RR?= =?utf-8?B?K3p2N3QwekUwbmo3ek9OLzA3SEl6OEVEcXpqaHVIcXZCVnR3cnhoZFdqR2xK?= =?utf-8?B?dU1DQ2I1ajl6RGl4Z3F2WEFiQ0JlMVEvdDVLaHlnbzJCSEtFQ00zK3VrRHZx?= =?utf-8?B?S1VoOVgwb1FFc2VrR1QydC9YYzJ2TDlhd0F6NjRIanFMeVBmcTJiZlpXTFla?= =?utf-8?B?ZDh2NzlTWjMxdDNNQ1dONDNuUFl4MS9mQ2lveUZaZzYxQUM3Smt1SzF3WlVh?= =?utf-8?B?WHdDdW00L2ErWDliWWZQZUN0WThtRTZnamxQbGJDSlN3SlFVZHVFY3JCbStz?= =?utf-8?B?bkg0cG9hcVR5OWkzUUFKMmJXcUN3THA3K2FBTXVGRjBuTFQwTmdBVThqNHhx?= =?utf-8?B?eUVobVVEdjJIYzcwblphcGpHdk1lQjZhYk9RRVZVekRJTEVrVnZiYWs5djh2?= =?utf-8?B?enBZcjVoTkpJaUREbnl6TnlEZFNlaVpHQnhKbSs3b3F2TU1hYk5DZ0ZyeWJh?= =?utf-8?B?SjlvUnVjT2ltQzh6djdqYVNkR1pGQzd6TTgreTJscCtnZUFhUjhGekIrQnJW?= =?utf-8?B?Y2NoeFVwKzlSY2FqUDlCdURlYW1mV1BGM0pOUXVURHA0YlhTSy8wNnhaeG1v?= =?utf-8?B?cHRZOExDSU9DRjNNUm5QUkhTdDhjcUV5UDNoYXlrRzdSU09XSXdjZ09kNHZZ?= =?utf-8?B?Q1hOcU9MWVh1WjQzdnBxNFplMEpFVkpEM2dPZXlVaHZibmJpUWFSMTdaWFBG?= =?utf-8?B?MUtueGFBRjA1SysybjNOZXBnSWFaRmlOYUNlemJzcGIrZjZIalhiZ0NCemN4?= =?utf-8?B?TUNabnpqZmFlR1FDYmpKUGpYWno3WW9PTWYxTWwvTGszQUwzejRVeDBjc29x?= =?utf-8?B?aklFbGV3MEwyZ2svSFNtOU5ycCtTRXJyZ2h6VEZBSGhxWnRia25jNDdtRXRX?= =?utf-8?B?S2hnME9ZZXpEenVaMk1EUzFlaFdGd0NnYlVRTHI1aG5kTGNjeXVCbnFOZlVm?= =?utf-8?B?WjRMczlqSUo1alpZLzZwOFhJMWdPL2t4QlZKcVozU2xBdldBaDFaQzVEU0pv?= =?utf-8?B?U0tMZWdlbXlXalNTSHNUajRaZUZSUWtvVXlHK09ldjlIS2daeUo1dCtHVkRq?= =?utf-8?B?TkoxL1E1S05NRHdWTFF3NzBvNlJhZ1Q0SEIwcWEvcFBWMXJDcGd4Sng2TmhY?= =?utf-8?B?MXp5V09KTDNLREdHNFJVSXZSdU9hVXpVVWJ2NkR3R3pyWjJ5ZmJxZThvY2Qv?= =?utf-8?B?L29Wc2FNZUFDT2NlaFNDaW5BNlhsZkVNVFY4VDJsU3BIUTBEaFB4N08wUU1h?= =?utf-8?B?VXdVSnpOUVdYdGhoUHc0b2ZnTTZudGFyQUJmMEZ6WVVpb01DeGtWSVNSSGQ5?= =?utf-8?Q?00jV4IWyWMsXBeYwDNPHlGIYS?= X-Forefront-Antispam-Report: CIP:4.158.2.129;CTRY:GB;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:outbound-uk1.az.dlp.m.darktrace.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(1800799024)(35042699022)(14060799003)(376014)(82310400026)(36860700013);DIR:OUT;SFP:1101; X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Jan 2026 17:13:22.5846 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 49c05e37-d0f8-46af-42ab-08de4fa264c2 X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[4.158.2.129];Helo=[outbound-uk1.az.dlp.m.darktrace.com] X-MS-Exchange-CrossTenant-AuthSource: DB1PEPF00039232.eurprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM9PR08MB6019 On 12/30/25 10:30, Christian Loehle wrote: > I'm trying to deliver on my overdue promise of redefining overutilized state. > My investigation basically lead to redefinition of overutilized state > bringing very little hard improvements, while it comes with at least > some risk of worsening platforms and workload combinations I might've > overlooked, therefore I only concentrate on one, the least > controversial, for now. > When a task is alone on a max-cap CPU there's no reason to let it > trigger OU because it will only ever be placed on another max-cap CPU, > as such we skip setting overutilized in such a scenario in a careful > way, namely still letting it trigger if there's any other task or the > capacity is (usually temporarily) reduced because of system or thermal > pressure. > On platforms common in phones this strategy didn't prove useful, as > even one such a task would already be the majority of the phones' > thermal (or even power budget) and therefore such a situation not being > very stable and continuing to attempt EAS on the other CPUs seemed > unnecessary. > OTOH there are more and more systems (e.g. apple silicon, > radxa orion o6, x86 hybrids) where such a situation could be sustained > and there are also many more max-cap CPUs, so more possibilites for the > patch to trigger. > > For further information and the OSPM discussion see: > https://www.youtube.com/watch?v=N0tZ8GhhQzc > > Radxa orion o6 (capacities: 1024, 279, 279, 279, 279, 905, 905, 866, 866, 984, 984, 1024): > Mean of 10 Geekbench6.3 iterations (all values are the mean) > +------------+--------+---------+-------+--------------+ > | Test | patch | score | OU % | OU triggers | > +------------+--------+---------+-------+--------------+ > | GB6 Single | patch | 1182.4 | 26.14 | 1942.4 | > | GB6 Single | base | 1186.9 | 71.23 | 573.0 | > +------------+--------+---------+-------+--------------+ > | GB6 Multi | patch | 5227.7 | 44.11 | 984.5 | > | GB6 Multi | base | 5395.6 | 53.17 | 773.1 | > +------------+--------+---------+-------+--------------+ > (OU triggers are overutilized rd 0->1 transitions) Not really important, but having more/less OU transitions should not be a criteria right ? If the goal is to use EAS as much as possible, it would be better to compare the number of task placement decisions that go through EAS between the 2 versions. (I think the numbers are convincing enough, this is just to discuss). > GB6 Multi score stdev is 43 for base. > > RK3399 ((384, 384, 384, 384)(1024, 1024)) > stress-ng --cpu X --timeout 60s > Mean of 10 iterations > +-----------+--------+------+--------------+ > | stress-ng | patch | OU % | OU triggers | > +-----------+--------+------+--------------+ > | 1x | patch | 0.01 | 10.5 | > | 1x | base | 99.7 | 4.4 | > +-----------+--------+------+--------------+ > | 2x | patch | 0.01 | 13.8 | > | 2x | base | 99.7 | 5.3 | > +-----------+--------+------+--------------+ > | 3x | patch | 99.8 | 4.1 | > | 3x | base | 99.8 | 4.6 | > +-----------+--------+------+--------------+ > (System only has 2 1024-capacity CPUs, so for 3x stress-ng > patch and base are intended to behave the same.) > > M1 Pro ((485, 485) (1024, 1024, 1024) (1024, 1024, 1024)) > (backported to the 6.17-based asahi kernel) > +-----------+--------+-------+--------------+ > | stress-ng | patch | OU % | OU triggers | > +-----------+--------+-------+--------------+ > | 1x | patch | 8.26 | 432.0 | > | 1x | base | 99.14 | 4.2 | > +-----------+--------+-------+--------------+ > | 2x | patch | 8.79 | 470.2 | > | 2x | base | 99.21 | 3.8 | > +-----------+--------+-------+--------------+ > | 4x | patch | 8.99 | 475.2 | > | 4x | base | 99.17 | 4.6 | > +-----------+--------+-------+--------------+ > | 6x | patch | 8.81 | 478.8 | > | 6x | base | 99.14 | 5.0 | > +-----------+--------+-------+--------------+ > | 7x | patch | 99.21 | 4.0 | > | 7x | base | 99.27 | 4.2 | > +-----------+--------+-------+--------------+ > > Mean of 20 Geekbench 6.3 iterations > +------------+--------+---------+-------+--------------+ > | Test | patch | score | OU % | OU triggers | > +------------+--------+---------+-------+--------------+ > | GB6 Single | patch | 2296.9 | 3.99 | 669.4 | > | GB6 Single | base | 2295.8 | 50.06 | 28.4 | > +------------+--------+---------+-------+--------------+ > | GB6 Multi | patch | 10621.8 | 18.77 | 636.4 | > | GB6 Multi | base | 10686.8 | 28.72 | 66.8 | > +------------+--------+---------+-------+--------------+ > > Energy numbers are trace-based (lisa.estimate_from_trace()): > GB6 Single -12.63% energy average (equal score) > GB6 Multi +1.76% energy average (for equal score runs) Just to repeat some things that you said in another thread: - for the GB6 Multi, it should be expected to have a slightly lower score as CAS gives better score in general and EAS runs longer with your patch. It is however unfortunate to get a slightly higher energy consumption. - The focus should be put on GB6 single where the energy saving is greatly improved > > No changes observed with geekbench6 on a Pixel 6 6.12-based with patch backported. > > Functional test: > Using the above described M1 Pro I created an rt-app workload [1]: > Workload: > - tskbusy: periodic 100% duty, period 1s, duration 10s (single always-running task) > - tsk_{a..d}: periodic 5% duty, 16ms period, duration 10s (four small periodic tasks) > Target system: 8 CPUs (0-7), 2 little (cpu0 & cpu1), 6 big > Metric: per-task CPU residency (seconds) over the 10s run > OU metric: time spent in overutilized state / total time; Number of > OU 0->1 transitions (triggers). > > Case A Mainline: > Small task CPU residency (s), 10s run > task cpu0 cpu1 cpu2 cpu3 cpu4 cpu5 cpu6 cpu7 total > tsk_a 0.124 0.000 0.000 0.000 0.035 1.791 0.492 0.001 2.444 > tsk_b 0.002 0.000 0.500 0.000 0.000 0.001 0.004 0.000 0.507 > tsk_c 0.000 0.000 0.000 0.000 0.001 0.000 1.895 0.630 2.526 > tsk_d 0.000 0.389 0.001 0.000 0.450 0.000 0.000 0.000 0.840 > > (Little CPUs 0 & 1 rarely get picked for the small tasks due to CAS' task > placement, which isn't deterministically "always picking big CPUs", but since > they make up 6/8 of them this is the common case.) > > Overutilized: > - OU time = 10.0s / 11.0s (ratio 0.909) > - OU triggers = 7 > > Case B Patch: > Small task CPU residency (s), 10s run > task cpu0 cpu1 cpu2 cpu3 cpu4 cpu5 cpu6 cpu7 total > tsk_a 0.055 1.907 0.006 0.012 0.002 0.001 0.000 0.005 1.987 > tsk_b 1.845 0.115 0.014 0.000 0.004 0.002 0.000 0.000 1.981 > tsk_c 0.914 1.069 0.007 0.000 0.004 0.005 0.000 0.000 1.999 > tsk_d 1.000 0.985 0.004 0.005 0.000 0.000 0.000 0.000 1.995 > > Overutilized: > - OU time = 0.1s / 11.2s (ratio 0.007) > - OU triggers = 57 > > (Little CPUs 0 & 1 get picked by the vast majority of wakeups and aren't migrated > to the big CPUs.) > > > [1] > LISA's RTApp workload generation description: > > rtapp_profile = { > f'tskbusy': RTAPhase( > prop_wload=PeriodicWload( > duty_cycle_pct=100, > period=1, > duration=10, > ) > ), > f'tsk_a': RTAPhase( > prop_wload=PeriodicWload( > duty_cycle_pct=5, > period=16e-3, > duration=10, > ) > ), > f'tsk_b': RTAPhase( > prop_wload=PeriodicWload( > duty_cycle_pct=5, > period=16e-3, > duration=10, > ) > ), > f'tsk_c': RTAPhase( > prop_wload=PeriodicWload( > duty_cycle_pct=5, > period=16e-3, > duration=10, > ) > ), > f'tsk_d': RTAPhase( > prop_wload=PeriodicWload( > duty_cycle_pct=5, > period=16e-3, > duration=10, > ) > ) > } > > Christian Loehle (1): > sched/fair: Ignore OU for lone task on max-cap CPU > > kernel/sched/fair.c | 6 ++++++ > 1 file changed, 6 insertions(+) >