From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1D264C433F5 for ; Thu, 23 Dec 2021 14:40:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348846AbhLWOkO (ORCPT ); Thu, 23 Dec 2021 09:40:14 -0500 Received: from mail-bn7nam10on2075.outbound.protection.outlook.com ([40.107.92.75]:7287 "EHLO NAM10-BN7-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S232183AbhLWOkN (ORCPT ); Thu, 23 Dec 2021 09:40:13 -0500 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=hZSoIMnKidb3ibjXtAyy+3v7sauDncr77OHRSORJbZX1c6HNTyZyHZKrr43E9NNBnAKRQQmzMvEclvin0sui5KU3TXKwyDfzAZB9Qi9osd9UroSPMeUbQnh9TiSDEMHE/ADzBryzYihnQi7cdhjTj1gaYXrsH3wgmIpaBirXVQw3GcWuEGeTdtnhpXXI80XWqHm9lLvIyo4wG6W9DJ0pG5s4FebdT2sYqPTCMQ9GusHqKqOOjR4tKQ972z17kN/e88IVYpoKmX1zeeQ1TYmrviis5Ns5Pk0YXUtyf1I2+TwPs0jnPoZQSteQiH5EMikPQnrvf6iTjxFvlGxo/g2e1g== 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=xV8IK+oXs7rHdBbkAe8Yr/piV3dxzGMe9FEIA8u26LI=; b=fgNAZu0z/gWoXTQWu6h71Dn9mBkMQbNteRuuthqzl9rj9P2Ocz7WbDeZdeoX/Yb4TED5NrfYfXVrcCJ6uf3WtptE7FAlhgdWcAY7qDZeWS7hL/oFXO1HM+1SAXP1zjbDf+uuLkZJzLXq47gG2+Ibffbxopc3hh8hYSxt7WRqHVGsDq9+mUqLQoixIuGC3A5igGlw6CkMT62iwlIVCQIgxJqsXIPaKX+OlLg2NVJpUUBb+69AhPk+weqfnwDtzf3K0MUwFfPmkQ7w8nJ97Z4i2HlqVwjFcztLHJV5NMOtl72OspQ2JxN2FxiZJVFljnJqIJVzAHHkD67JYATBkuSaOw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=xV8IK+oXs7rHdBbkAe8Yr/piV3dxzGMe9FEIA8u26LI=; b=uAFTcHt1o0QUXSo3aG9e7IwXbhHh9BqVUgNK2CxqjBa4KOnfbzGlwZHD4o2KHug01bJ9750Xun2jXVL86CMVOJDhFvutSaVafz1n4fp4+KbznTl7j5UdGPCYnGPHETX/p1LVVQwrhMfl+rWFcaW1oDSclKo7++IDcRw4/5S/8+8= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from BYAPR12MB3286.namprd12.prod.outlook.com (2603:10b6:a03:139::15) by BY5PR12MB3777.namprd12.prod.outlook.com (2603:10b6:a03:1a9::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4823.19; Thu, 23 Dec 2021 14:40:08 +0000 Received: from BYAPR12MB3286.namprd12.prod.outlook.com ([fe80::4899:90ea:bb12:518]) by BYAPR12MB3286.namprd12.prod.outlook.com ([fe80::4899:90ea:bb12:518%7]) with mapi id 15.20.4823.019; Thu, 23 Dec 2021 14:40:08 +0000 Date: Thu, 23 Dec 2021 20:09:46 +0530 From: "Gautham R. Shenoy" To: Vincent Guittot Cc: Barry Song <21cnbao@gmail.com>, Yicong Yang , Peter Zijlstra , Ingo Molnar , Juri Lelli , Tim Chen , LKML , LAK , Dietmar Eggemann , Steven Rostedt , Ben Segall , Daniel Bristot de Oliveira , prime.zeng@huawei.com, Jonathan Cameron , ego@linux.vnet.ibm.com, Srikar Dronamraju , Linuxarm , Barry Song , Guodong Xu Subject: Re: [PATCH 1/2] sched: Add per_cpu cluster domain info and cpus_share_cluster API Message-ID: References: <20211215041149.73171-1-yangyicong@hisilicon.com> <20211215041149.73171-2-yangyicong@hisilicon.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: BMXPR01CA0093.INDPRD01.PROD.OUTLOOK.COM (2603:1096:b00:54::33) To BYAPR12MB3286.namprd12.prod.outlook.com (2603:10b6:a03:139::15) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 89ec6e70-ac10-4dad-4494-08d9c6221d81 X-MS-TrafficTypeDiagnostic: BY5PR12MB3777:EE_ X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:10000; 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:BYAPR12MB3286.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(366004)(6506007)(6486002)(2906002)(316002)(6916009)(5660300002)(83380400001)(38100700002)(6666004)(4326008)(8676002)(86362001)(66946007)(66476007)(66556008)(26005)(7416002)(54906003)(186003)(508600001)(6512007)(8936002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?S4/ncqMC4KRok+p3JGcdbML2s7BwtW+aPWPlpf7JYwuTPTcCC7LmRmnYBu/a?= =?us-ascii?Q?mNIx7FN5uhJIkcvTMJ1stln5FLRppUXYFur9xha/n6ziqIRTx0i4CovmPTFf?= =?us-ascii?Q?oG/G60U6BnoWNS8osM/SAfZMmzsqywV3qqzjIAMYB2sosUwcRg4/0TqEuBr5?= =?us-ascii?Q?A5/iacpKmFf3Al5WX/1WtVcjJyqMxxDZhTPsviJyeTLEZ5pM1nIlmhkd3PbL?= =?us-ascii?Q?eViE8gBVDzBod6uLMag44DqiEw0ABQG2s8BUtYuJ/VquASrmwyGDp0iQT/sQ?= =?us-ascii?Q?fsbilnyT0bUKihT1awhxvtR8zOzJ8g0wJwyPOWSqT7IA9h/qxwlL3YvlSO36?= =?us-ascii?Q?tqOYRvHQFLNpwMxBygzyvNZkRy5vvHWR0mcnPJaBAIgQjUZSkRpUC+mkwjYh?= =?us-ascii?Q?x+eLnSTy4i3e8ivMDFsAW29yHyy2CdmmUYA3Tqd5sV2MsmHyspC46yISSR2i?= =?us-ascii?Q?N4WXfr4Aa6HPUbUI3RdEev1UW6Zc7ipU0q7DkF5IDFzrOzNPob7JCtW4TG3U?= =?us-ascii?Q?4k5MvxzoQN+5qGzcDASOBrmUba6iW6mlq3iVIgcGewvS7njNm7jX3eNTeaYl?= =?us-ascii?Q?CUy1IvCSq/cZyO5zPuiJgfPiGKUyTbl7GJcwgV++C5CVdGPIGnROjlLg4Jmt?= =?us-ascii?Q?F1OrNkhDPtyNNDxuNyzpRNlFoRr8Fq049AvqlZv32qqtg9CFBwqfX0RYfo1r?= =?us-ascii?Q?4cJZj/3PwQAC01I/6bF5qyWJ3YK15xHTSC63rZgrS+finRxV7dNbKQapxrSE?= =?us-ascii?Q?nJaxJyNKRCO1PO5Z5CDJQ36WF2sW87EGUoOhaRQX6TyJ5K66yO93uNOCzKPr?= =?us-ascii?Q?tq6CdagyDC3/nZvpSJeL/6d6KrwErS+01Wql7icH5nwEwJ3pupcaHbr0s8ue?= =?us-ascii?Q?b7ptaLNg2bo500jKh+MGpV3+QeXTw6gC/RhsTRrHn4CgBhqCN9/4TjgxJd/r?= =?us-ascii?Q?Abr7Fhb1PSKELiuDG/EuD+yokQlf6F47y14znaNcNbJ8UAXOBmQvEFizoPwc?= =?us-ascii?Q?YSdDPIJQ1qMvSOh2bb163NK9DyYJZwq92yYU1XMJdnIFZ8RuAdZX1R2GYXPQ?= =?us-ascii?Q?5d3B103KSSvn20GmpMivLnGkgqIfYK7VAkhq+wfA4vt8FMN2rhnVhoFx4QBl?= =?us-ascii?Q?sd5TLCZ7PtfMNTcau3K3qqpmD8ktkK3+4M9u4rdK8Vl/czZELgdg0Tep6Crz?= =?us-ascii?Q?j7e7uCzQ5MXjXWkOJfWLKkJe9n8P6CMuGs1og9be5ObK1KhxCw9oKx+qEvZo?= =?us-ascii?Q?RVbnBgJzCsrfa3kY1k0uVROEY/l8w9KgmYCihmSphRILa44NMV+BI2BtzdHR?= =?us-ascii?Q?SxYCZMmiFUYI6kq44Bt3FYbwQxACH2uxJO7LLdcW06Pc2fklSryj/hFGc1D2?= =?us-ascii?Q?RhGKPtArCwcJiN9bXNrnAi0EFMJn1xn5jy9amYjA22rC0YmGdUvpsfaEe9NN?= =?us-ascii?Q?tSTdSzbh1TNpm1K0pK9otPiOYkmiqFJ475Ms3UxPHGiNqe51KLIOCYbd5XRv?= =?us-ascii?Q?RRbwbDlKoprZla+kZBqa45/um1db2x/fR/Hizd/mGIGmSeFjfsWeKuksDCWc?= =?us-ascii?Q?rSwFdmetd+XKaLDE6RVFo+/rKUPgB8hisX1EfTlm/k54idKnJ0uBUNvN56JL?= =?us-ascii?Q?W0e7ofJRyRRydfnQ/ySdC/Y=3D?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 89ec6e70-ac10-4dad-4494-08d9c6221d81 X-MS-Exchange-CrossTenant-AuthSource: BYAPR12MB3286.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Dec 2021 14:40:08.1771 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 9SDPQrzE0iTBzQ8/MsASUQjnOyjWp0FWwbfJ8n1v0G7Ux369oP3UY3lao5pjj2PFXJEqu/ClgxbGircGBFmVyQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR12MB3777 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Vincent, Barry, On Wed, Dec 22, 2021 at 02:33:37PM +0100, Vincent Guittot wrote: > On Wed, 22 Dec 2021 at 14:14, Vincent Guittot [..snip..] > > > > > @@ -669,6 +671,12 @@ static void update_top_cache_domain(int cpu) > > > > > per_cpu(sd_llc_id, cpu) = id; > > > > > rcu_assign_pointer(per_cpu(sd_llc_shared, cpu), sds); > > > > > > > > > > + sd = lowest_flag_domain(cpu, SD_CLUSTER); > > > > > + if (sd) > > > > > + id = cpumask_first(sched_domain_span(sd)); > > > > > + rcu_assign_pointer(per_cpu(sd_cluster, cpu), sd); > > > > > + per_cpu(sd_cluster_id, cpu) = id; > > > > > + > > > > This deserves a large comment to highlight that the new code above is > > not self contained and relies on the fact that it is done just after > > looking for LLC and sd and that id and sd must not be changed in > > between inorder to ensures that per_cpu(sd_cluster_id, cpu) equals > > per_cpu(sd_llc_id, cpu) if there is no domain with SD_CLUSTER. > > > > and per_cpu(sd_cluster_id, cpu) might not be cluster but llc > > Maybe you should not name this sd_cluster_id at all but > per_cpu(sd_share_id, cpu) = id; > > Then you have a function named > > +bool cpus_share_resources(int this_cpu, int that_cpu) > +{ > + if (this_cpu == that_cpu) > + return true; > + > + return per_cpu(sd_share_id, this_cpu) == per_cpu(sd_share_id, that_cpu); > +} > + > which returns true when cpu shares resources which can be LLC or cluster +1. This would make it more readable than overloading the meaning of cluster itself. -- Thanks and Regards gautham.