From patchwork Tue Nov 7 21:57:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ankur Arora X-Patchwork-Id: 162782 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:aa0b:0:b0:403:3b70:6f57 with SMTP id k11csp544473vqo; Tue, 7 Nov 2023 14:07:20 -0800 (PST) X-Google-Smtp-Source: AGHT+IFdwEX/Tgbcrk4oIYn4j3TbROjwyinOYbgevmtajbCBMP0MCqMzeosUfPj9Xg1w9/3ZaUMI X-Received: by 2002:a17:902:d2cc:b0:1cc:4a84:27fc with SMTP id n12-20020a170902d2cc00b001cc4a8427fcmr299326plc.52.1699394839999; Tue, 07 Nov 2023 14:07:19 -0800 (PST) ARC-Seal: i=2; a=rsa-sha256; t=1699394839; cv=pass; d=google.com; s=arc-20160816; b=WQ56e1LQE2Bj+I+nCsyJayX7M4UmVKtIJUV9BDLj4XAwG4RTtkJSReNHC5on1aaP+t MZJuOgjWMpTZ4PoxZNjKY7ohALviyMy5PslIzCzvlXjvCbwOy2KxjP8R7wpN8S+HsYd8 8d2Ln7ZCKHqmuIbHPe1Hab2xDK0sIKmf6JzgeIg4RFEQz4UAtrkMA99zDSVDvh0JKHl1 w8t0mI0eP7nAtUcQrJCtcRuLLRBTGfTDepIylLyf8hCfozjiGdJeitQkEQUsPXabrkin elI5WNxZy3sooyb2UAGOetRFvP83V0L09eEUUOL6/avYeIG3lcSRSH7MvJrecbK1BAsT QUmg== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:content-transfer-encoding :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:dkim-signature; bh=zMJzLbouFyv2RVTsLsfrlR2gP3yXNftDrwME+78WkYc=; fh=WKqKhB7paWertAf2JRO/DCaA8jol6XlnBoV5owBcc5w=; b=i9sOxBHgsVYdmFKi3fYFPUvgPMCLKLBnSAXiKytyUIfTiLpg/hLB/WVVFQ3NZQ6sAb 0UZ1IATJUWmWEMbUma12j8K/ERluXZGKTluczaf7bOSvbjjIlUYoR9AcJUVkpL8psX8D Rv7nXBqRUlsV+cOevLDS+KDPTJbK8deiczLeErrnSn+78ZYsEveqIDJeTLV8FC1p76Ay ktaJkEAwLM/hq73xpZGD4/TescRBDHrUlXOkJZS2gnzzwYU21EIQN72/ehR+hvBvD7iY XxeM5ivlufb5cUMFrpNlGlO1YYtBQvl7FYbY5E+USEBt/pnUCX/MT7kqXCfaohh5kD6h I/5Q== ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2023-03-30 header.b=1EkMhJVr; dkim=pass header.i=@oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=d84mPyk+; arc=pass (i=1 spf=pass spfdomain=oracle.com dkim=pass dkdomain=oracle.com dmarc=pass fromdomain=oracle.com); spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Received: from lipwig.vger.email (lipwig.vger.email. [23.128.96.33]) by mx.google.com with ESMTPS id v18-20020a170902ca9200b001bd9e2b4b46si598777pld.601.2023.11.07.14.07.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Nov 2023 14:07:19 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) client-ip=23.128.96.33; Authentication-Results: mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2023-03-30 header.b=1EkMhJVr; dkim=pass header.i=@oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=d84mPyk+; arc=pass (i=1 spf=pass spfdomain=oracle.com dkim=pass dkdomain=oracle.com dmarc=pass fromdomain=oracle.com); spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by lipwig.vger.email (Postfix) with ESMTP id F22E781A2040; Tue, 7 Nov 2023 14:07:12 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at lipwig.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344313AbjKGWF6 (ORCPT + 32 others); Tue, 7 Nov 2023 17:05:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32966 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235591AbjKGWFG (ORCPT ); Tue, 7 Nov 2023 17:05:06 -0500 Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F5E73C07 for ; Tue, 7 Nov 2023 14:01:32 -0800 (PST) Received: from pps.filterd (m0246632.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3A7LJpqk020714; Tue, 7 Nov 2023 22:00:09 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-2023-03-30; bh=zMJzLbouFyv2RVTsLsfrlR2gP3yXNftDrwME+78WkYc=; b=1EkMhJVrfl+oOjerPpslH1agBGduW8LBW/Ab7svAdk7OMXqqInFgVNcAuUkVDPuiPqsp rk+1mA36BrvIWfIt0QDhjYZNqKHQtvsClnK4/ZAji1xfr2BsIc3zZZWfs9zIFEoYG8b+ +8y8dYzDm1GIHw2tHZv71xRuN2/sYIECASQjuS8QtfIUAvU+1IoSCwrBehnwiM9PNJgB 12ZTV+RygOUYUpsnKpv9wTTIeklO/eJLiyZEETcrRBvp506gYQuZYWt2Ci67b64hRRHC ofNCueFGyLIBLELbO5fAThrTdX9FLkpv6xRN1lghDP6SLh64fHx1XoYKHzx9lhsGRg8E uA== Received: from iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta02.appoci.oracle.com [147.154.18.20]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3u7w2202tg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 07 Nov 2023 22:00:09 +0000 Received: from pps.filterd (iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (8.17.1.19/8.17.1.19) with ESMTP id 3A7LIlPk000377; Tue, 7 Nov 2023 22:00:08 GMT Received: from nam02-bn1-obe.outbound.protection.outlook.com (mail-bn1nam02lp2041.outbound.protection.outlook.com [104.47.51.41]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 3u7w1v9kns-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 07 Nov 2023 22:00:08 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=jjZpnUoQDQyrVKi2yDq5PMUFal/ooiKVRV3J9N3+iwbo59IYRoZG58+4tQLQZ0qkOTyJNS5HTlTZSybCkD4Zb0wZav41huAE9ZmobzMwluYHbQ1ZPbZoy9hnlO53HWS0mVfaK8FmWS9kGSFQBVkBGMlxbRzcZ3LWCLerBaJyxdyyaCARf4BXZQ4le6jstq5Pf5Fl0IwB7IRp7kWPfD1pCg2urM0TPdHwRFbVYuUYh4S5d4lJeWC0NCVcOCrux24B/63couPKMlcxZQpnjroirI/NDZbQEuLKb+kPcB98CktZmKFgn9uX++KhL9ewFcWZboiuCFWFWzY8dFg/t9V5YA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; 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=zMJzLbouFyv2RVTsLsfrlR2gP3yXNftDrwME+78WkYc=; b=ebl17F7OVaXwzvitsucNuLOF7rviudOBTTCbk3ED2zqaxFwuStGI0CbZZCP6XBk4sE+gXOpw/q2FRuEzn12Mii8wAcq9Ags8NurnRct+Yl2Wd9C+I07+gcA6bshB50R/oYyKcIZdBLGfbwGaU5SbXR2tcEjXhVCQXZVUk7CGFUHbzMzVO7NhztOdPpP8cb8NoXYeTXmKLA2Sp4E+/H3ntwO0ae2sEA+CJdwcKci3TDOTXvwRzyp4ikWb9jcJ8DEwkAZeg/26nnz+1EvaWF7FkuvtRrRLDXSUg2ueVjfFvKqbfjVRryyl19W75/D04oJXAYZousJW2klfZBBZdKubKg== 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=zMJzLbouFyv2RVTsLsfrlR2gP3yXNftDrwME+78WkYc=; b=d84mPyk+SzBo0CIOALdxMJA9BhCiyv+dWkiSmCHxnIKfyAjCPELMx1bOyO1962UMCYHv2LeZ9ybHNRv2pvakPBnl8LOTA1vqEFW8hBN8/56Z30vwYo/jCTsspmybGJizQpF45Pi4rop2ZiRQqmlJyjXGm830sc1NYmfr+LUVl/s= Received: from CO6PR10MB5409.namprd10.prod.outlook.com (2603:10b6:5:357::14) by PH7PR10MB6275.namprd10.prod.outlook.com (2603:10b6:510:211::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6954.27; Tue, 7 Nov 2023 22:00:05 +0000 Received: from CO6PR10MB5409.namprd10.prod.outlook.com ([fe80::1ce3:4a8c:4c99:acea]) by CO6PR10MB5409.namprd10.prod.outlook.com ([fe80::1ce3:4a8c:4c99:acea%7]) with mapi id 15.20.6954.028; Tue, 7 Nov 2023 22:00:05 +0000 From: Ankur Arora To: linux-kernel@vger.kernel.org Cc: tglx@linutronix.de, peterz@infradead.org, torvalds@linux-foundation.org, paulmck@kernel.org, linux-mm@kvack.org, x86@kernel.org, akpm@linux-foundation.org, luto@kernel.org, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, willy@infradead.org, mgorman@suse.de, jon.grimm@amd.com, bharata@amd.com, raghavendra.kt@amd.com, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com, jgross@suse.com, andrew.cooper3@citrix.com, mingo@kernel.org, bristot@kernel.org, mathieu.desnoyers@efficios.com, geert@linux-m68k.org, glaubitz@physik.fu-berlin.de, anton.ivanov@cambridgegreys.com, mattst88@gmail.com, krypton@ulrich-teichert.org, rostedt@goodmis.org, David.Laight@ACULAB.COM, richard@nod.at, mjguzik@gmail.com, Ankur Arora , Simon Horman , Julian Anastasov , Alexei Starovoitov , Daniel Borkmann Subject: [RFC PATCH 47/86] rcu: select PREEMPT_RCU if PREEMPT Date: Tue, 7 Nov 2023 13:57:33 -0800 Message-Id: <20231107215742.363031-48-ankur.a.arora@oracle.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20231107215742.363031-1-ankur.a.arora@oracle.com> References: <20231107215742.363031-1-ankur.a.arora@oracle.com> X-ClientProxiedBy: MW4PR04CA0216.namprd04.prod.outlook.com (2603:10b6:303:87::11) To CO6PR10MB5409.namprd10.prod.outlook.com (2603:10b6:5:357::14) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO6PR10MB5409:EE_|PH7PR10MB6275:EE_ X-MS-Office365-Filtering-Correlation-Id: c088578e-4d52-43e0-a1dc-08dbdfdce66c X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 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:(13230031)(366004)(376002)(396003)(39860400002)(346002)(136003)(230922051799003)(64100799003)(451199024)(186009)(1800799009)(66476007)(54906003)(6666004)(38100700002)(6916009)(6506007)(316002)(66556008)(36756003)(5660300002)(7416002)(7406005)(41300700001)(66946007)(6512007)(103116003)(1076003)(8936002)(8676002)(4326008)(26005)(6486002)(2616005)(966005)(2906002)(83380400001)(86362001)(478600001);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: ojujoicF3jZMZ5TdNYQQEXrXwxnednnSdtTQus0of5oDGjmXFOtbRZaeqmzcPEBvFdVPI+URQdNMXUMDIVEhwXiBzUq0il5uiGpyaHFFxitqiv+gpDOCXPIgqqSHxrFO8sDoxiR/v0uhc7twF3hw3E3eEdfz+SVIIWe3pAlGdq8wDA/9h0NXadu1t1lqvO7a0qSlg+ME69GWbCqWIEuyekM6CM19u/mRdtEGClGaJ2hlMOXCGq2kyCuhNRF3zbN5wTVGsomy1Hi3RBHckJT7PAG6FBZCB/vR3Mkfnm+pdwCqKDwV3XnwofDrBaKMxEjMj4sx+F3lZyElOYg7P62cT2caPXMrJUH6yBbMStxquO3aSQYjssnMcS9v2RR/47KHeGG0F5z7I9mHbVikUHmjBHXZ/faHLuy9zpxlVewXnrG7q9JtwqwpjoqLCPpO/vmeYmrkiEAsUcBQRH+xMK1FcEnAw6GzkOHB8iwXovslY1k1YB3/4DxgaX3sZVy/N+pw0o7wdDvyI5LepoDsUc/Ty94sTXWNwYasLogKeEdjDv7fLhjht80aSrAO+awA1ld1JR2jpbbGx/tWcLdGkqRzixHO2VgrAW/lahqtnsOxIxJzyiG8INsNpsSpgmFlll3xXCGyqnJy0J2zrq41r7qt5OuFTcBYXmFGoAQ10yjWNILWlmfaBnBNsUDz/3ynjoe/qROoLff+oVBnarVbqkVgMqyDvsHyUBFzcNzO6LpybBFKXLiBf79fYhHeENQ9e1BJ1xysZrjVxWHHuaCVzI1z/uVEz1+iIqfHoS/JpSmZ5uQHX9U0SryMEN6sGmSYlGXU1zWIakCjADI0dsstjvQI1jjECIPgHms7fYX9CSbeN5yI+w1zYTi39h2PaWPWuPnwp8pG5AliFKCn/D502Fi4cqew3NkQ5rMuQz8wJusFv0h8eIfEH2tPDk0Xp9JUYRs8xsk4j3h42aII9fT3V0cwkU+FmwC0NbL5w18tcZ0CN1MsQkhgMkFKiPpozR322mKWHQFsI3wmyGVqqgQCuoo8pjMgtOILzh27OMRjNfgaeqVUQtiyGUBffuIPc/BegC+BTzEchZZv/XQKRri3hwzp1GsnMYKMgaCnlRMMuGeYlL6cvDHa/nTYP1l9GBb6FL3yXmdfkekswqI6KdXI0FvQYUNhqPdzJzlfEFehOfpIF2IvMwP08uIjBbo0NEayHPHOqAanX7EvnHoZKkwsmyVST0jwzej83gYRLLXgdE0VOkzvSNfiOz1nxTV5F0lnJRwz5sCogg9rVjQysY4DtXxnUxqaHhYDsRVEpkwFSmk49lDg4+0DaaICso/gT09fxfKwC5zXj68J7lgebPiI7ZZBxjDC1YIb8r2mik95jrLRc1PuY5zxAcVDt5wv6BCpLX12iiTclLyuuKCp2QBTgcq4KAMuxW+Exx/Sd0yOXl/sa2UZL1oyy9yFLpmmYHouiX/Ayb/Yesu0Jqg4jr4xvRZ/kfvprRheUvowTiGgu+jlNT4Dyin3Y9yeu+oNHsbbHr2bZkX+Jmca3GE2EQ6/OhO9rcqkn3ikSbPQNxvUn/RKhtBYAqPpMCK0eJ6H8f1E6JYaQ9DmJunEWYzKo18HNSZp6944rKimtLBjk2q4rJUjtmU= X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: c088578e-4d52-43e0-a1dc-08dbdfdce66c X-MS-Exchange-CrossTenant-AuthSource: CO6PR10MB5409.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Nov 2023 22:00:05.6166 (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: jegKBUH+FfAh+SAaKqZON/nvITRnAIVz+D06dE8BecvzPzhtAq5yIeM0oNFyLxielW5VvHHsrFPPq2QODw3SXYasenXQlAHyMtxD8EV3KIY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR10MB6275 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.987,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-07_13,2023-11-07_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 malwarescore=0 suspectscore=0 adultscore=0 bulkscore=0 mlxlogscore=999 phishscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311070182 X-Proofpoint-GUID: hEL5cTwxOZyib5HOyaMQchY1SdatqtAM X-Proofpoint-ORIG-GUID: hEL5cTwxOZyib5HOyaMQchY1SdatqtAM Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (lipwig.vger.email [0.0.0.0]); Tue, 07 Nov 2023 14:07:13 -0800 (PST) X-Spam-Status: No, score=-0.9 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lipwig.vger.email X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1781944643674919461 X-GMAIL-MSGID: 1781944643674919461 With PREEMPTION being always-on, some configurations might prefer the stronger forward-progress guarantees provided by PREEMPT_RCU=n as compared to PREEMPT_RCU=y. So, select PREEMPT_RCU=n for PREEMPT_VOLUNTARY and PREEMPT_NONE and enabling PREEMPT_RCU=y for PREEMPT or PREEMPT_RT. Note that the preemption model can be changed at runtime (modulo configurations with ARCH_NO_PREEMPT), but the RCU configuration is statically compiled. Cc: Simon Horman Cc: Julian Anastasov Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Andrew Morton Signed-off-by: Ankur Arora --- CC-note: Paul had flagged some code that might be impacted with the proposed RCU changes: 1. My guess is that the IPVS_EST_TICK_CHAINS heuristic remains unchanged, but I must defer to the include/net/ip_vs.h people. 2. I need to check with the BPF folks on the BPF verifier's definition of BTF_ID(func, rcu_read_unlock_strict). 3. I must defer to others on the mm/pgtable-generic.c file's #ifdef that depends on CONFIG_PREEMPT_RCU. Detailed here: https://lore.kernel.org/lkml/a375674b-de27-4965-a4bf-e0679229e28e@paulmck-laptop/ --- include/linux/rcutree.h | 2 +- kernel/rcu/Kconfig | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h index 126f6b418f6a..75aaa6294421 100644 --- a/include/linux/rcutree.h +++ b/include/linux/rcutree.h @@ -104,7 +104,7 @@ extern int rcu_scheduler_active; void rcu_end_inkernel_boot(void); bool rcu_inkernel_boot_has_ended(void); bool rcu_is_watching(void); -#ifndef CONFIG_PREEMPTION +#ifndef CONFIG_PREEMPT void rcu_all_qs(void); #endif diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig index bdd7eadb33d8..a808cb29ab7c 100644 --- a/kernel/rcu/Kconfig +++ b/kernel/rcu/Kconfig @@ -18,7 +18,7 @@ config TREE_RCU config PREEMPT_RCU bool - default y if PREEMPTION + default y if PREEMPT || PREEMPT_RT select TREE_RCU help This option selects the RCU implementation that is @@ -31,7 +31,7 @@ config PREEMPT_RCU config TINY_RCU bool - default y if !PREEMPTION && !SMP + default y if !PREEMPT && !SMP help This option selects the RCU implementation that is designed for UP systems from which real-time response