From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) (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 3CD64358D17; Fri, 9 Jan 2026 09:07:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=205.220.177.32 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767949622; cv=fail; b=h3VQ9zFtWfGxhfFyClABtzwDRQsBavXSO8Dz1AQXonFLDLCHtOWnoofRKvsIh65fOzzZIqBLqh3DJhO86H3GdGdcsTdJY71Xy8C+5oFJ78xbk1v24gZv12ImXcNBgd2xSbNxbRXLhMdyRxbHR/mJ8sz2yILCUFXK/mfNXLP7gho= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767949622; c=relaxed/simple; bh=2fjjAfZagefNp6gmfctQRbm3TDqqstZIiVySkMaZCio=; h=References:From:To:Cc:Subject:In-reply-to:Date:Message-ID: Content-Type:MIME-Version; b=KcddOnTyRY9cPK8/j7I6OPkpfDZr1/e0IsYecG29mFFIcZjr3nhM0Qi/uORKhnM2wFytc30chlu/+JZaE5KfYD0Ugncw4W8ywcrok8AFGapFsiSB0X1CsU1m1FnXGIMM2Pz8MPSbYzYcpuxQrYzZrUW4XIlCujjHkYgE4UTgnCk= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oracle.com; spf=pass smtp.mailfrom=oracle.com; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b=oqVzSFgn; dkim=pass (1024-bit key) header.d=oracle.onmicrosoft.com header.i=@oracle.onmicrosoft.com header.b=xXNkoW0w; arc=fail smtp.client-ip=205.220.177.32 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oracle.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oracle.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="oqVzSFgn"; dkim=pass (1024-bit key) header.d=oracle.onmicrosoft.com header.i=@oracle.onmicrosoft.com header.b="xXNkoW0w" Received: from pps.filterd (m0333520.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 6097bdCF3070430; Fri, 9 Jan 2026 09:06:37 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=cc :content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to; s=corp-2025-04-25; bh=mOtlHWLpbnQmO9MWGC L8u7MmmdbMucfSoTmUlmlc89k=; b=oqVzSFgnszBP0bLFHDVwWzkQIF2+Q6y7uf nykcIvnOcygP7fG3PHPQeafA8GI8kp7IzScbWKNihmPNEQ10JiKUd1d5JHP/eYfL 5Hwf8+HZRd98CXJEclolPmTTFR2IpvU/msa7JuvEhxvQpZ0aeLRSRcmJGt/vZ/h3 tFX5vuDJwzWkgEjMYIbYTNOVIbFpBfG9D0eHVjwwmeAVlQQ5WrdXyoGNhZkTARWa acejIdF4fTdvt4hVX7FZYlwEMFj47ZmmjlOhCu3So0dJbW7Y1n1GgWPaDcLztAY5 VfTn0gb6eHSUvX+arsfZ1nEGnNBofXmU3DIPXCI7nSxySCp4wzNQ== Received: from iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta03.appoci.oracle.com [130.35.103.27]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 4bjwecg30b-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 09 Jan 2026 09:06:37 +0000 (GMT) Received: from pps.filterd (iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 6098ME2U026510; Fri, 9 Jan 2026 09:06:36 GMT Received: from ch5pr02cu005.outbound.protection.outlook.com (mail-northcentralusazon11012001.outbound.protection.outlook.com [40.107.200.1]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 4besjpdtdu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 09 Jan 2026 09:06:36 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=yrgyt3mg8qFLD8QeoJQWNxz4ngYUofpAfAPJM6CMNjM1jdWXeGfBkJ80DfciYjHt8F8gu5GgKEj+wCFshMRPf3+v0cQadF+NMJ2RQFTOjhTND250glUONeSyQv2Tu6OCPniwgY83n0ac3r54mjJcUszrm42DVNaslFI+85wXeBXtiqDdXAQwi2gOViQK/cDRW24dzNGo9HAObIVtvTFZWGs3xwpPQGVgGlRi1HpPyGGxex3It6NaM08nAg+q/Uag0bXX9g+GJpdOcUDYa7O+HxHH6e+ggM1z3UPD3+dl7vk8zBB3Wt7AB55RhJetOFaH671pXpVvJUV0/3PjhkB6sg== 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=mOtlHWLpbnQmO9MWGCL8u7MmmdbMucfSoTmUlmlc89k=; b=GzpgbeDbvXT9gNCQdX9iUpjXvNnnWRMw0kUPfLzmHgOKxWaP2kDQ/CGoDK/fOY9qEP248zWKBGbJ37hznmobl5SUXDvNhKzbRnwftWUTar1iDlGeoMN06w1uKOqvqLG3Ucx1iwuliZrZ3Or2+pjG9mZVGjl1WMm7D03UZX3jT/CmDnS4R7EUZM4xGSsuX/jzZyf7BEj6R3h9TVnxWAD4Z76NyUC4B67Q/uyo2Tg3uk6AXj0df1Amr6bhkrqeBxVDdrd737P12MEVkHWeZQDQ+nD0Y8i1bUKPeGNBM6SUA085hrQiA2Pd7OGvZ355PSnMYxiNtG89tOkWFGa+T43Hdg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.onmicrosoft.com; s=selector2-oracle-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=mOtlHWLpbnQmO9MWGCL8u7MmmdbMucfSoTmUlmlc89k=; b=xXNkoW0wHbcu75fb7RVjUaZKOnYuhLnf2iocrtj6/cwddnUqDagHDkeMOeyce6o4DC1Ypkfs8JHmYNHoYvXHnb/LfrukV3YY+GZox9PwUXqa1Gyrr/pDcIbkex6AfQ5nujBDe+y1iM8vEWp7SOL5rh/JwmT/EW0mtrxiQAmwIw4= Received: from CO6PR10MB5409.namprd10.prod.outlook.com (2603:10b6:5:357::14) by BL3PR10MB6116.namprd10.prod.outlook.com (2603:10b6:208:3bb::7) 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 09:06:33 +0000 Received: from CO6PR10MB5409.namprd10.prod.outlook.com ([fe80::3c92:21f3:96a:b574]) by CO6PR10MB5409.namprd10.prod.outlook.com ([fe80::3c92:21f3:96a:b574%4]) with mapi id 15.20.9499.003; Fri, 9 Jan 2026 09:06:33 +0000 References: <20251215044919.460086-1-ankur.a.arora@oracle.com> <20251215044919.460086-3-ankur.a.arora@oracle.com> User-agent: mu4e 1.4.10; emacs 27.2 From: Ankur Arora To: Will Deacon Cc: Ankur Arora , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org, bpf@vger.kernel.org, arnd@arndb.de, catalin.marinas@arm.com, peterz@infradead.org, akpm@linux-foundation.org, mark.rutland@arm.com, harisokn@amazon.com, cl@gentwo.org, ast@kernel.org, rafael@kernel.org, daniel.lezcano@linaro.org, memxor@gmail.com, zhenglifeng1@huawei.com, xueshuai@linux.alibaba.com, joao.m.martins@oracle.com, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com Subject: Re: [PATCH v8 02/12] arm64: barrier: Support smp_cond_load_relaxed_timeout() In-reply-to: Date: Fri, 09 Jan 2026 01:06:32 -0800 Message-ID: <87zf6nnoiv.fsf@oracle.com> Content-Type: text/plain X-ClientProxiedBy: MW4PR03CA0290.namprd03.prod.outlook.com (2603:10b6:303:b5::25) To CO6PR10MB5409.namprd10.prod.outlook.com (2603:10b6:5:357::14) 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: CO6PR10MB5409:EE_|BL3PR10MB6116:EE_ X-MS-Office365-Filtering-Correlation-Id: f63b24ad-f587-491b-11a9-08de4f5e62ae X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|366016|1800799024|7053199007; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?u36CU6C/GbZK9bcXtPe8P+8+IL6F/ZxQlHZSV3PwvqpLSS3Zt/tGQ+xAXbrc?= =?us-ascii?Q?ju/tHCpQ/JrSupKmPgmDrfkPWQXfPaeum8N/49xXVnvnsFZ4nRWagz17y5mD?= =?us-ascii?Q?5oEvxAv7ewJh/vKFvKU8CrX8jzXqYRPeINHNW46vCFV/qrAGxywUbOdUKkXk?= =?us-ascii?Q?Qj4kQMSZsINbxdjRTiZlhdPSNtMegymfomg0sx7TpLnLS/dqrXcghJoq2cb9?= =?us-ascii?Q?dn7IVR1iSioaMFSB7yMr4fuJ0Kb2tbVbpjv85f/a2bMDWwKzoN/O7dwrsTAv?= =?us-ascii?Q?SAY+2beKDGDx2UCiZGavwWpljkafd6ozqhjh/3AQvRYheyflLdIoaUz/vk5K?= =?us-ascii?Q?04bvzEbySHQkxIoA/PM/FqWZuG35HK0+34N0u9srmoMKk9SZIZe22A879jyP?= =?us-ascii?Q?l8Tg4J0d4aAZ4vwyjGwWfc4gmj3gh+6+eVtY3wgCz6lO3qXS0vPewIph3PLz?= =?us-ascii?Q?LtNj0fLRgaesltVeycQNk7Sm6o4F00KB/tuiPTEWKBtjXvYZxlC1yMZ5VBNL?= =?us-ascii?Q?Qa/DAdm2pbYdTDN7Q2VKdJ8xF2DRr3adES9RLqn38QpF4EbKPei1IHs24Maj?= =?us-ascii?Q?ivYzPCjwoqsTKFSE+KARyIJ9WSNa1pYohhnpxyX4CHTNGAHl46ewlocoTYGI?= =?us-ascii?Q?zH9eyrPXB+l9UC6dEq7kz3trbUzFphpERfS0Ulweq6NRJ6h7TtnlMVAelMDo?= =?us-ascii?Q?g9+Kp8VESZ8E2lw129KCWWRI6G3grNWU4K0ZQ1PRcBWT7zDVaeqUsMM+dIMN?= =?us-ascii?Q?00iwMwYu+jhFQNHkQdTmgmBvOCq9HPp7tCbnVuRmnQXgOwLeWlIc9lDS5r+5?= =?us-ascii?Q?JAoVIWPWFZIb/WTxznCwbH12DCLPKGeU601//xAmAlABWclyKf0Hs2Ll7pwd?= =?us-ascii?Q?JJZjMNxaoeSXIaTIQLbKQv09setES2+u2CMvw3cD8h2Cn0BjP7vV9tkZUmRl?= =?us-ascii?Q?auiFnv4ENFGhDsmNDxpYTfqYPfNUqsMpMA/N/M9cXKQMm5Tw5+K4320wO5+d?= =?us-ascii?Q?wjiQfoI6Qb1ue85C6958ZrrGmn/hHnUla+Infx/yCDLHaPv1gER8rb+yl7JK?= =?us-ascii?Q?a//66QveiNLVZMYh1aXX33xofqJZ3yQl9IWTgzEZy2G6VIwMAGi4c6xqhIxf?= =?us-ascii?Q?9QECxDq1b72ki4c2gRUnxvSLU+D9Nkoe8Yn4whXKLo0dXA8eTZhHrFhiAdIb?= =?us-ascii?Q?6ql0ZYlvBQm9OpsSapLtquD/mKBzp+sG2cQihc6PNMob71EuBKf5uqHdU9Mg?= =?us-ascii?Q?yIEo42NvE7futcbw43FvT0hCOrsYPPw0tDeta5ZjSX2MT4RGu29UaQctRrwF?= =?us-ascii?Q?/1YYJSyXQG9kD7Z5/zynXWEicSxT+4l0WTL6dXfxJFNcFqaOylMcbbTnv6Gm?= =?us-ascii?Q?WeBMJdLVYjkNSrioAqyy9nkqFOodStPyye+/Nooqu889deG3FZiD1P9FkeX1?= =?us-ascii?Q?bJfwX891GV3Ua5VR3wAsJNUXH7YfrhEq?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CO6PR10MB5409.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(376014)(7416014)(366016)(1800799024)(7053199007);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?SiJHQSbyvwBIzS1zqNZ6mOutywBAAquy4jgly3FOJ6EnQEDMml/jyKmwoH0d?= =?us-ascii?Q?Mgh8VXUs7P9MYv13P8R7ofRU0uja4b7rpLzrpEEOjImFIV2KMpapEUH/A875?= =?us-ascii?Q?nWBFLutJLo2FTZJ1zu0idzQBsiWc7HYOwjtTlSn23Cf+DuZix8N7w5Zxo6Ow?= =?us-ascii?Q?tiR9xAOKxFWSEm4TaiDLlhgq9wwTPMYvTGJYkBKpIZKGbZLeKL4oBMdGzUGQ?= =?us-ascii?Q?QRMAk7qolfVfhCPI/0CBsycmkLkRIrAZxZIi0w2YpwcpTchfBpLPFk6oHoMv?= =?us-ascii?Q?wLYr1u2mVkrqhvvBSPgNVw1+QDuNgE30+WF17gfIGeBpQob63NMAZxXWUamB?= =?us-ascii?Q?jl9fWwBoJXl7PEBJ5iSCYQ9O/knz3lHEVym352NJNsSpiaAbZRxwbKwIUfLb?= =?us-ascii?Q?UYFiFXwmKImQs1wq5h6polbPOjCbys+IinC0CCBabg1qwY9b+F3UI4HufiOi?= =?us-ascii?Q?QhCXq+FaZnTNp1Eyg8SBONzBBeCf/Va6P4ea7DNgG7jsZuZdrFsaoTflBxj7?= =?us-ascii?Q?HPg6QJRCGjl64mvgiIcHm2qkbFSzo0fCGTsoAqdbtoZB86KueQMDowVIWwuP?= =?us-ascii?Q?K7w78KQYnbinygaHPkOmEm7aNAQ5olvhpaJ2n8CTOwvXd921wSksSNLSReLs?= =?us-ascii?Q?ytE3iahjl0w0r1yn6EolmQ320TjVz5YEQ1vpMnmAiCvLwXbEC5Vhixgt+5km?= =?us-ascii?Q?CtPyaF3fQJJMQrh5ICMYCIO4kKpw4QAmpGT7zXflV3kHKqdEulnrsIibOWuz?= =?us-ascii?Q?LEMXGdqDsiZ0i+KtIn7SSRJaMEO+b1oThEmQDpmpOFe5FFhAgAbCwD6QvqxD?= =?us-ascii?Q?8MXMIo6S4sdTswE5d9v8yBUIvC9ZroKs3ThZXicHNEzcSs1ib2hXMVlgHuwr?= =?us-ascii?Q?D93OW1u0U951mJn2zj2zM6PePto0k2b4cdar8LUZb6Zq/D5LU/naYb4cWTkM?= =?us-ascii?Q?jwQYYJ+mC+iUF5gKCSjCyPTElF3kFAp5iUQVVbFvZeDpwODycVUpqpyP8Kfw?= =?us-ascii?Q?G2H4HBMnGYgdhskK+wHaTD4I2sNMiHfFNkXWH1a+HeAWFfhR22xi2gvsHxL3?= =?us-ascii?Q?PiRgFT4kFG2fFyQ7LULsi8p6UqGfxK4I2PrIHJEuLUQX3O4Zu0GvW/jqOjBJ?= =?us-ascii?Q?QN5Sbds569YpX7p6X2ZnuQ+JVN4IEGsUYQPF6gnJlVdGI4qrM42oCXIZCroh?= =?us-ascii?Q?OIrOGIxBjqUfW4N3T4PsaImEq07zhxRGCBoZuoLkun6QdJM2Htqnf9JYyMYA?= =?us-ascii?Q?kU8w2LeYNC7z9Nz3Ru+CaKgbihOibh9D+acZIMvC1xUcd3vzESVHEh8Olrmn?= =?us-ascii?Q?9nvhjQtXAIpp3LCYFS75MlqXxobNrQHlbrH7HzBd+pjDj+SLuWtjshPjsqS4?= =?us-ascii?Q?BgjNbaTXT+bShcEWJbDady8U0SxDpnvyN5yg3xZvqB+qTtdDoP3wfsL99gk1?= =?us-ascii?Q?MD/lnSXak2vBYvQUuH8QAXhnDhJWmbrZWiByDcuHJSJfwkuvNjvMlC+RsU4l?= =?us-ascii?Q?bcc/tJVEwmJFfinWT7lsbnfa3Wj61K/rnR9RvVjaulY/Kaq9+k5ufWv69yD7?= =?us-ascii?Q?sertuFXahHJR8klxKuP+8HA8e2O1luGOdenaxlgjCn36ExExAeW+kYzGMaBv?= =?us-ascii?Q?iI1ZIzEcI2yX8oAe0pl28RDvxtaEAmaHzLZR1141X2wW1u5SqQNXkt6T9vx9?= =?us-ascii?Q?gFIwhws37Luv1QFD2R9TiR/KSFQfrmYCL6KXWsZ2WVH/vyGJ7sUYdNcoMcoc?= =?us-ascii?Q?b1XdDCB1WK8F0DhGph59n/55mQXo3gg=3D?= X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: oZtQzQG6x9tDPVHrAu5uRnoEZgFBy7m/vIMUckWzn6fLfoit3NS6T/DaB8UT1Dfqchyaek/I+v7S3uBgxAmZwnX/ro9zUxLFZtwW37ZzvONu1TZl7Dq2J6dxv41M1BouZFut/AkfhCDrexo741Bm7Y+g4LUXCTG08ntGIyiw68hDF2a+/P+VGBtMRL5uWvQ6kNMtbYbjNkqjBSpoASaIFvKwtVuz3OumCBCEHTsSLAAVloYl5QyZAZekrJyqa2sts0qPdM/QQ0exay+MBL7brtBLloaoGKBQFIdW/EFaqFT6RRVi0qswiJOWqhaRr/WyXzsZI4TXjz0nwJHfgFSg41zTKuH3Mhzpw6FRFEX/EyxQM/qf3q6mAh2hbIvEAC3Rz4t1qCX0UmUdlQ67+XIlN8UniBTBke3WcEgxToNIZNCq+I8xd3394qS7R66W/YqEvOF77B8LZcmQpuJaqtYcIsiOdlwRF7J04U3AlZRhIXH8Dh1gPXaC9+qxiT6C7CWpinj2rKCingeev5bWnXZJnVeytCsRNr6nSUzkWxFMk8k8Hu+dFDo+YBKoyDdzXxk1RicQhSpAb3eLB7vP1ccN6Cqr399vZ3aPGapB/zZgwnQ= X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: f63b24ad-f587-491b-11a9-08de4f5e62ae X-MS-Exchange-CrossTenant-AuthSource: CO6PR10MB5409.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Jan 2026 09:06:33.7556 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: W/Tb/jSDgaSyoDMHumoginkcWagXBhLF0SlnHt8mE14/5M2LBzETou8xap4ZoPis19L9vmzSDQwzcspjfFk3abY/PwELd96pciEU4N1dOa0= X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL3PR10MB6116 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2026-01-09_02,2026-01-08_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 bulkscore=0 malwarescore=0 spamscore=0 suspectscore=0 mlxscore=0 mlxlogscore=796 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2512120000 definitions=main-2601090064 X-Proofpoint-ORIG-GUID: TFZNcWEcCyKQ2VjMbny2gsWMMWMGK6cK X-Authority-Analysis: v=2.4 cv=Vrsuwu2n c=1 sm=1 tr=0 ts=6960c51d b=1 cx=c_pps a=qoll8+KPOyaMroiJ2sR5sw==:117 a=qoll8+KPOyaMroiJ2sR5sw==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=z/mQ4Ysz8XfWz/Q5cLBRGdckG28=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=xqWC_Br6kY4A:10 a=vUbySO9Y5rIA:10 a=GoEa3M9JfhUA:10 a=VkNPw1HP01LnGYTKEx00:22 a=VwQbUJbxAAAA:8 a=7CQSdrXTAAAA:8 a=JfrnYn6hAAAA:8 a=yPCof4ZbAAAA:8 a=vCsAaxQ3v4rsUVRk0TYA:9 a=a-qgeE7W1pNrGK8U0ZQC:22 a=1CNFftbPRP8L7MoqJWF3:22 cc=ntf awl=host:12110 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMTA5MDA2NCBTYWx0ZWRfX6dqk2PQeO+Em 7Nc/NtsSASBC35BWbKTwWAOO3Gc+1cVHbdp+2cf3Zx8ne7CYu/imIvRlhl/rjt3djIqQoHiEf86 H18Yqo2ueiZkt2vCV+bgdXkPFAvBgAuOr4p66NBGsjSvo48R/QO2rCOYYJfuzbRGHQCqwOGMhQD CAJ9JvzFbCbn8C7CWbRY/9ngdMS87lBHRQQBB8bmvtcPfrU6fBIZ4DeSem3RDCx6mT30uaNJU86 z/J0i4pQZ9AjZtnDQ8iEP8vIdzOML0sHi1tmSZEO7VpDKr+aQLYapPTEupBS3D5zkXlVsBomSFC ZkZ7q7AwOU1CB5uXnrjaCbVa/kt4M3eTj0wpKJ7xFt7SBfoy4Tjn+1d7/cbAgKMTPMyLQTa2mJL TWtWyRYqoZvC9G2pN+gQDElA3shevZDskByO/MsOIhreB/iuyL1JfYgoxACNZ/b/jD2nA9FB/n1 yxcqR3Xb4WlnWVNmEiUl/lUkfbzWMh+BJgBe6dEE= X-Proofpoint-GUID: TFZNcWEcCyKQ2VjMbny2gsWMMWMGK6cK Will Deacon writes: > On Sun, Dec 14, 2025 at 08:49:09PM -0800, Ankur Arora wrote: >> Support waiting in smp_cond_load_relaxed_timeout() via >> __cmpwait_relaxed(). To ensure that we wake from waiting in >> WFE periodically and don't block forever if there are no stores >> to ptr, this path is only used when the event-stream is enabled. >> >> Note that when using __cmpwait_relaxed() we ignore the timeout >> value, allowing an overshoot by upto the event-stream period. >> And, in the unlikely event that the event-stream is unavailable, >> fallback to spin-waiting. >> >> Also set SMP_TIMEOUT_POLL_COUNT to 1 so we do the time-check in >> each iteration of smp_cond_load_relaxed_timeout(). >> >> Cc: Arnd Bergmann >> Cc: Will Deacon >> Cc: Catalin Marinas >> Cc: linux-arm-kernel@lists.infradead.org >> Suggested-by: Will Deacon >> Signed-off-by: Ankur Arora >> --- >> >> Notes: >> - cpu_poll_relax() now takes an additional parameter. >> >> - added a comment detailing why we define SMP_TIMEOUT_POLL_COUNT=1 and >> how it ties up with smp_cond_load_relaxed_timeout(). >> >> - explicitly include for cpu_relax(). >> >> arch/arm64/include/asm/barrier.h | 21 +++++++++++++++++++++ >> 1 file changed, 21 insertions(+) >> >> diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h >> index 9495c4441a46..6190e178db51 100644 >> --- a/arch/arm64/include/asm/barrier.h >> +++ b/arch/arm64/include/asm/barrier.h >> @@ -12,6 +12,7 @@ >> #include >> >> #include >> +#include >> >> #define __nops(n) ".rept " #n "\nnop\n.endr\n" >> #define nops(n) asm volatile(__nops(n)) >> @@ -219,6 +220,26 @@ do { \ >> (typeof(*ptr))VAL; \ >> }) >> >> +/* Re-declared here to avoid include dependency. */ >> +extern bool arch_timer_evtstrm_available(void); >> + >> +/* >> + * In the common case, cpu_poll_relax() sits waiting in __cmpwait_relaxed() >> + * for the ptr value to change. >> + * >> + * Since this period is reasonably long, choose SMP_TIMEOUT_POLL_COUNT >> + * to be 1, so smp_cond_load_{relaxed,acquire}_timeout() does a >> + * time-check in each iteration. >> + */ >> +#define SMP_TIMEOUT_POLL_COUNT 1 >> + >> +#define cpu_poll_relax(ptr, val, timeout_ns) do { \ >> + if (arch_timer_evtstrm_available()) \ >> + __cmpwait_relaxed(ptr, val); \ >> + else \ >> + cpu_relax(); \ >> +} while (0) > > Acked-by: Will Deacon Thanks! -- ankur