From patchwork Wed Sep 25 23:24:25 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ankur Arora X-Patchwork-Id: 831447 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) (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 924131A3BCE; Wed, 25 Sep 2024 23:25:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=205.220.165.32 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727306736; cv=fail; b=fwT/cTb6arO/F/JyFUIMprYpykxT5yz7ouHKD/F4OtsF5Wl+5zb8eBTW45nQh2CLEHJl7jKVJpHCl9IC0PSqrRivEcmtsJEIQlhOHEt5BWi5+WMKUC1EqnmGTsmv9/aglfil0Zc2juOFrGuldj9BvxP2E9stLQgpQYlBOu9Y/j8= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727306736; c=relaxed/simple; bh=HKQF9VbzfrDmmNAi16NJj7zNQTs3mK9FPNV2eemLJC0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: Content-Type:MIME-Version; b=L7Dh6D7FYtJx+zfSu1wpwsnrOhTIEYz3Ro2HsJmHGec2on/XCQtHK3KfOalY1gC0dZuRDlG8BWlBSHcOXgGoyM/iy0qc3PWCiS1buLVT68on0haxe9v/YWoGDITF0nhNmu08b1HHkewYNILIBYxSWhVwCbX/RPBd/+t4sGDYxZY= 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=nCSR7E/z; dkim=pass (1024-bit key) header.d=oracle.onmicrosoft.com header.i=@oracle.onmicrosoft.com header.b=OMkXaU+n; arc=fail smtp.client-ip=205.220.165.32 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="nCSR7E/z"; dkim=pass (1024-bit key) header.d=oracle.onmicrosoft.com header.i=@oracle.onmicrosoft.com header.b="OMkXaU+n" Received: from pps.filterd (m0246627.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 48PLn1ft022966; Wed, 25 Sep 2024 23:25:00 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h= from:to:cc:subject:date:message-id:in-reply-to:references :content-transfer-encoding:content-type:mime-version; s= corp-2023-11-20; bh=B1X78YsN0cj8Fn6HaXRey6YxVjkXUcZi+iwMeNWnMkM=; b= nCSR7E/ziuHEnmWfpvEKs7cj/YOkjjEmAQjOumPrcwUsmPFBRqbYwBOQ/TqVDroX Gk7eNW8MVpBGpRSq19CWkeSxQXsoHmJpHD9XG05bThxmpJamWTEtu/nzdZ+odruS a5rByFQ9RCKeUKGngzg9mz/PALhtk6xUq4FBu0o11fMN8GVtj9+EdRsp0hpPG7d+ 3ZrOKlxRRmRnzXs1BbmdbX8Ab0L2VXN6abqZNh3rIAsqj0G/++k+KyBOEdfowEll sg0wXtNM529OSLs/8DPphivk01686tqAltPCVKZB6f5ZuhUpLjqaceVzlbFHnYIO 3QEmLuDH4UrNVgbkCsCQBw== Received: from phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta02.appoci.oracle.com [147.154.114.232]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 41smr1bt13-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 25 Sep 2024 23:24:59 +0000 (GMT) Received: from pps.filterd (phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 48PMUr1W026114; Wed, 25 Sep 2024 23:24:59 GMT Received: from nam02-bn1-obe.outbound.protection.outlook.com (mail-bn1nam02lp2044.outbound.protection.outlook.com [104.47.51.44]) by phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 41smkban7x-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 25 Sep 2024 23:24:58 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=dKPh2xgLTgPlY/o6K8VIB9OQtS+gDcDSvp6RlrTyGMks18iz9MZu87MfyWCu2d1IckJZyBIIcy20s+vUMMMytCJLFL6qeuh1eJARctH+VAP0APBMQSXd81YldKRYiliTosKcRjz/OgUNwSj/JbSLL1ZkVqqX3qCJR0AEKEzDm8/bhfIstqpSyFq9PO7MnHPhYyq87JI6PccUMV4LTbKWuGzulV8CXE0KrWbzE/HjSoAXsy+ZK8xvESArP/mwXpp24BrGtDD9adD8/EmUgFwfN8JSk/tRyUTUd0ZK+tqGS+LURBY8MxQDgOF/0X7YarAbMQi/i8+JVwAo+RT8vHYyCQ== 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=B1X78YsN0cj8Fn6HaXRey6YxVjkXUcZi+iwMeNWnMkM=; b=OE/SGNuSqjJyXaPJQ+gzCs5gUzcy1UX6plgEGcVjUeqNd4s+mBfWonxvvcOZzil/Ttzt45H093ZYERh5lOKxNtduI0BbefVpFGcG8zpU1Mc/pacmBWlxUvzumojOSmJS/XIsX3P08vuSKWDtf8rdjNIbd2Ne7E7g760R3NYJICha9JHav8ogOEKTOYuTqqycyu1qHUzSvff83Zk909X+EojBeu26PPpyvDAP3k7H4OTtsaEBzZYOuWGSSnW5P/Cc8Q6syz1qKjE7DOTJfAgDod0loMVJ3UUDH7rFA7FwJJpqt0CPBuYMqjc7uvLXpAqyFlVcTyUeaaSh7e96pow1fA== 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=B1X78YsN0cj8Fn6HaXRey6YxVjkXUcZi+iwMeNWnMkM=; b=OMkXaU+nGAblIJAwTtDg/YpoBxmHveWyM2jFJbAHdbAODkqiiRuffpF80SwxZfRU2lHqjKpxQ73DqmXsawvGIiKL01olWdZStha4P7lrLqymKse2lna2mprcD2MyKfL2HgkBKMelyE2MyLLr87NOMbK6LTmZl1wwJlkD+o0vFRw= Received: from DM8PR10MB5416.namprd10.prod.outlook.com (2603:10b6:8:3f::19) by LV8PR10MB7943.namprd10.prod.outlook.com (2603:10b6:408:1f9::22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8005.20; Wed, 25 Sep 2024 23:24:56 +0000 Received: from DM8PR10MB5416.namprd10.prod.outlook.com ([fe80::e085:31f:84d1:e51a]) by DM8PR10MB5416.namprd10.prod.outlook.com ([fe80::e085:31f:84d1:e51a%5]) with mapi id 15.20.8005.010; Wed, 25 Sep 2024 23:24:56 +0000 From: Ankur Arora To: linux-pm@vger.kernel.org, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, pbonzini@redhat.com, wanpengli@tencent.com, vkuznets@redhat.com, rafael@kernel.org, daniel.lezcano@linaro.org, peterz@infradead.org, arnd@arndb.de, lenb@kernel.org, mark.rutland@arm.com, harisokn@amazon.com, mtosatti@redhat.com, sudeep.holla@arm.com, cl@gentwo.org, misono.tomohiro@fujitsu.com, maobibo@loongson.cn, joao.m.martins@oracle.com, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com Subject: [PATCH v8 11/11] arm64: support cpuidle-haltpoll Date: Wed, 25 Sep 2024 16:24:25 -0700 Message-Id: <20240925232425.2763385-12-ankur.a.arora@oracle.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20240925232425.2763385-1-ankur.a.arora@oracle.com> References: <20240925232425.2763385-1-ankur.a.arora@oracle.com> X-ClientProxiedBy: MW2PR16CA0054.namprd16.prod.outlook.com (2603:10b6:907:1::31) To DM8PR10MB5416.namprd10.prod.outlook.com (2603:10b6:8:3f::19) Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DM8PR10MB5416:EE_|LV8PR10MB7943:EE_ X-MS-Office365-Filtering-Correlation-Id: ad64c0c1-981f-4f8c-ddc9-08dcddb9441f X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|366016|1800799024; X-Microsoft-Antispam-Message-Info: W3ed6RVZUyP9KJdUvOkfjwXRlrLgx7auS+cAXbXmHKEWgclQshb8Pyk7Kio/bjw4CCcK2htg7ju90BnPQbFPV+ogA4XUazGxQ2pwM2x1zY4iGIBDdY3IJwp2cT0O02XPkjaNdhXDKUJPfNaN+ugnHuxP9xZwoqO+GsBbCuE2Qbyww3hGgV6vDD5bUuv5XIUxrDi2nkl3u2k/UQQ9/XbS3nnByl6Nx2P907aU6OSBowyDbIyI05pCoffDiMop+QyZJIIxBHNj35fTRK5Iaoy6DKL+Q5OyZiXeaOpD6/GehfiYpO9AwGaboMMZW2Jtan+YMi0Rnot967Ej/oVWMgiJwqBfmLq6ZLxf7xU5mgeot0IwQG1vurlLxMfi6wB1cmIYXCNdTcJz9AY4FhvFeIKOFu0vci9kXv65hsY/9pQa4K5HK1O6nIBMjKObBFAykA04C/XdMpfjSyCt2zePgpFpvtqRQFwk7jeCf0O/bnTlm1Z+K8yrgfcMXpwK28qFrTO4i5HnL8Bkl54c91JpWpsOy7naaLAp2L0i7B8sm4N6OT+bGbbsk4vXokIK7ss9cYgFChPb1NMmK/gzkfAcpqJDzPo8dN2qK8nIVESSt2p3UTt8B9KpvyXByHemOUnDTm3iS8aSTPPfs+q2arour9DR5FWt7G5dpWFQ48bnMHqFNQvKSZgIm/ir707aef/qQkFHLf+RF72PNLl6guOnCa6pqIZjObP566ckYP54akOqx4oycz9O36t90DSCEOqV0yX1Xcv9KLpaOk9+e8uq2b1gZQiPutAJwaPOtuByTif3AyU+8RkY9idQTKh2BOp6J/8ZBd3h/4E/7vRxUo2UdqepYLJPie/9RQzmG1w4IwEDPCIIZ7GTfzz+xW3t/zncocwNeGjbWtBIuOysBGrdfejEk58BhgvhIQgCkMapjwWSKxT8m1SKbUtWZu42MlP7obgGBj48af+zFDxJq7eEF6OK/KObu7CJCvlHEBzOjZ8vwZzWM9X7ZABO6iH0Sl4Mu0/pPoAiXVaNjW5+z5JAmHYKov/Xlt04X1jud6QFqVdQRGMjaYZCkUUNGcy7gE95L38r5j9eczJd54uh84Y/TSw/gk6ij4e+Qa1+zHlpMX07YZ0JRM3uFy6MhwzTJRDbtcLt3++N3sQMi5mPqmCsUhPBITLJbiNxQ+vK7gM/B/UjqjsTxVLyQtVQiliQPRjLAUfozcIdBwGab4WzXPBBDjrGo2mrru6G/a5IWplHRI11oY4cYZsi0OHZSww0cYnJoT6L+KZvxOC2YoFRT/zguG4oQA== X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:DM8PR10MB5416.namprd10.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230040)(7416014)(376014)(366016)(1800799024); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 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 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 5lhf5fa9LFCK9wwmzu+mQSOkWZG5ET4YAPJC7pA+HcX6A8wl5H0mwhVZ7CqAZ/5mmeyjYljTeH/930AWhUsinp/LHSYorvjhSluEO/RyCM1EIJ5HLB8HIk+4G7jqRKPfSzyw9XVi7OKt/cXBlTATeywyuumqZ8L+zQ58PooNQ7ATp87Ss3juOnCrGN63CA7KR6yw3LMp3nFGzZT+H6nXMFezOWXjua85daPQxHCcq2KTVCIaMWBaXaKKdw4msX0ROZTgx84TbliyOz5gyPZesF9V2rO63PyHSevnWqoL7r727y+nT7hFGma4H+veMTNDmSWUmgZ5nTMuIR4iBrVNZN7zg4HxTIkBQGsurHxV+H1ahh7drU/otwE4JL3TZ7dJbgfoKt7oLfZ/NmGKA5SV8NGFKufTndaB+9Ar7aZRXCbfgocKLO+XOkIkiIt2bhLA81NI5xaqy7Luyd4UdhhRLrqoLhT3mmCyokHHpQKKOwnKYq0gWHPGyroPVrE5GFm7qksBs1e7VWNWOI3gZNRVCI1hUZ7iFkEnnIJAeJkbbfFvCJJwabxQLcWTuuqsaN3GWQgBlosiuuA9kRl3SsNouM78g+uqFfURcg8wa/HNHDM= X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: ad64c0c1-981f-4f8c-ddc9-08dcddb9441f X-MS-Exchange-CrossTenant-AuthSource: DM8PR10MB5416.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Sep 2024 23:24:56.2718 (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: n2xT34rneJ/1CHzgFGs6JOjgPsnHbU67geWcPgZptCQqjUgIW6i33zZamdX1LtX5POLrcXMmCPR+x1OrDLi4xLarNovydWuJ6wgQ5DMiysY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV8PR10MB7943 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1051,Hydra:6.0.680,FMLib:17.12.60.29 definitions=2024-09-25_14,2024-09-25_02,2024-09-02_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 mlxlogscore=999 phishscore=0 mlxscore=0 bulkscore=0 suspectscore=0 malwarescore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2408220000 definitions=main-2409250164 X-Proofpoint-ORIG-GUID: 2wcIx7t27r2Q0zq_zn-7MQg59D1XUwjE X-Proofpoint-GUID: 2wcIx7t27r2Q0zq_zn-7MQg59D1XUwjE Add architectural support for the cpuidle-haltpoll driver by defining arch_haltpoll_*(). Also define ARCH_CPUIDLE_HALTPOLL to allow cpuidle-haltpoll to be selected. Haltpoll uses poll_idle() to do the actual polling. This in turn uses smp_cond_load*() to wait until there's a specific store to a cacheline. In the edge case -- no stores to the cacheline and no interrupt -- the event-stream provides the terminating condition ensuring we don't wait forever. But because the event-stream runs at a fixed frequency (configured at 10kHz) haltpoll might spend more time in the polling stage than specified by cpuidle_poll_time(). This would only happen in the last iteration, since overshooting the poll_limit means the governor will move out of the polling stage. Tested-by: Haris Okanovic Tested-by: Misono Tomohiro Signed-off-by: Ankur Arora Reviewed-by: Haris Okanovic Tested-by: Haris Okanovic --- arch/arm64/Kconfig | 6 ++++++ arch/arm64/include/asm/cpuidle_haltpoll.h | 24 +++++++++++++++++++++++ 2 files changed, 30 insertions(+) create mode 100644 arch/arm64/include/asm/cpuidle_haltpoll.h diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index ef9c22c3cff2..5fc99eba22b2 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2415,6 +2415,12 @@ config ARCH_HIBERNATION_HEADER config ARCH_SUSPEND_POSSIBLE def_bool y +config ARCH_CPUIDLE_HALTPOLL + bool "Enable selection of the cpuidle-haltpoll driver" + help + cpuidle-haltpoll allows for adaptive polling based on + current load before entering the idle state. + endmenu # "Power management options" menu "CPU Power Management" diff --git a/arch/arm64/include/asm/cpuidle_haltpoll.h b/arch/arm64/include/asm/cpuidle_haltpoll.h new file mode 100644 index 000000000000..91f0be707629 --- /dev/null +++ b/arch/arm64/include/asm/cpuidle_haltpoll.h @@ -0,0 +1,24 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _ARCH_HALTPOLL_H +#define _ARCH_HALTPOLL_H + +static inline void arch_haltpoll_enable(unsigned int cpu) { } +static inline void arch_haltpoll_disable(unsigned int cpu) { } + +static inline bool arch_haltpoll_want(bool force) +{ + /* + * Enabling haltpoll requires two things: + * + * - Event stream support to provide a terminating condition to the + * WFE in the poll loop. + * + * - KVM support for arch_haltpoll_enable(), arch_haltpoll_disable(). + * + * Given that the second is missing, only allow force loading for + * haltpoll. + */ + return force; +} +#endif