From nobody Mon Feb 9 16:13:19 2026 Received: from CH4PR04CU002.outbound.protection.outlook.com (mail-northcentralusazon11013029.outbound.protection.outlook.com [40.107.201.29]) (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 2366642315D for ; Tue, 20 Jan 2026 11:35:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.201.29 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768908919; cv=fail; b=PaP0Tf9wCZ9VaU+30utqeQn2DADZ+/ZquGswwBj0dCGXtp5LtbguTCVLfQwDUMvFef78btpNKCPdXu7AnoFvUUwYiWcYuQmAjMy9BMBRJb8cGK8KK3111aM0J9flupPa9ofNAXcP6hqFPfBeUo5DJB2XYPfde6mCulVvIwVLVk0= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768908919; c=relaxed/simple; bh=vWZiaf/bPMZKejrbbnj9jhaAJQpdopzITqX6x/Fg1xI=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=a0+1hgfV10+PI5vGzgbWIU9jatjkbdGrCdTRLhKn8Pe+IAS2pub9CrhhhbTz48kRntUDs1JY+PPDRIagustpZ9+IHZKHCSAm0Tu387Raz/zQGSRgTUxy2xlWS3ZIsUs15fQz5RCwBVMaEOi1ALTSVwx+8ENRgHk/VjkucCdFu1w= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b=5XRAKIXn; arc=fail smtp.client-ip=40.107.201.29 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b="5XRAKIXn" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=sQVABBLrjipMYQ9dysU5ZNkv6RJHhPMO3uNYTBj53lYdDu7i04c4BPLeA44bNFJHh5RVHRSFhIDULkH2G7zhdXngIOXon17+gLb84HF7D2E9J9EYh1EDV8i4PeJMUZ/iI5fHbQWivtOuAZqHQVCVadPHJ65F30yJpNvmLTHrJGjxi9CiNN5M8Cw1ze2mnDtolxBjmhjYU5A+y2tbFgcafaFkV+D2a3SrVjiFvwc0ysR3SwfvQ7zeVC4lI27yuHE4S5HznAH+8HJR4E9MO+9IgLbCw/yCUCr2aWzmqf0Xw479U65E/v0jNk32Wj1XO4HKNzg6f8V09VB+mVueCA0d3g== 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=MIroPjMtfWc2sFFSZpO7o8pd9yF/Gig3cyMQEYHDd1o=; b=Ex7JS3J0CmTYnkzGlJFfdlZcj37PxQ0cG2i8/IYYuIdFA7BdG8st/X76wK1wCTqV5qJ3QdWqewks87sKg64eo6lHgWbrYpVrMNJlRWn/YO/HMhUuiUxeqk8JL339/m7r8YVNGfBxY8aO+ZBseaFEdV1QYKtUL3kO2WbXxycEgM000/usFTow7W2oy6JwRQ+coBoCgHYmc6PzQNGy7v1OKkTooSSMtCVkSVQCDkjcorSRSu/RMDx8IEbs1QnrdKevD41XI+OUS0jwJMSiKmMyQN5YT+gB6r4LO0dp8JklIuRu53Q9TpnmfNbHTin1IyMlzSqLmRXUxYeT81Ias1Hrdg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=redhat.com smtp.mailfrom=amd.com; dmarc=pass (p=quarantine sp=quarantine pct=100) action=none header.from=amd.com; dkim=none (message not signed); arc=none (0) 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=MIroPjMtfWc2sFFSZpO7o8pd9yF/Gig3cyMQEYHDd1o=; b=5XRAKIXnFHGmbYy0/rP6d7xPgr3rt8WsoeAEkr83wTo95dzZZjXkhyDEtbMJ+ECJjvWYVc1L1Q6sld758S9OJOg2zquPn6zgWty3O1XJeDNbWgbJjyW23Jx1q612Cie15oXqFEgSeRluD32+px45u3621ygFUjajtWCgMOW84Vc= Received: from BL1PR13CA0255.namprd13.prod.outlook.com (2603:10b6:208:2ba::20) by SA5PPFB2BF91BC0.namprd12.prod.outlook.com (2603:10b6:80f:fc04::8de) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9478.4; Tue, 20 Jan 2026 11:35:14 +0000 Received: from BL02EPF00021F6C.namprd02.prod.outlook.com (2603:10b6:208:2ba:cafe::df) by BL1PR13CA0255.outlook.office365.com (2603:10b6:208:2ba::20) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.9542.9 via Frontend Transport; Tue, 20 Jan 2026 11:35:18 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 165.204.84.17) smtp.mailfrom=amd.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=amd.com; Received-SPF: Pass (protection.outlook.com: domain of amd.com designates 165.204.84.17 as permitted sender) receiver=protection.outlook.com; client-ip=165.204.84.17; helo=satlexmb07.amd.com; pr=C Received: from satlexmb07.amd.com (165.204.84.17) by BL02EPF00021F6C.mail.protection.outlook.com (10.167.249.8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9542.4 via Frontend Transport; Tue, 20 Jan 2026 11:35:13 +0000 Received: from BLRKPRNAYAK.amd.com (10.180.168.240) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.17; Tue, 20 Jan 2026 05:35:09 -0600 From: K Prateek Nayak To: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , CC: Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Chen Yu , Shrikanth Hegde , "Gautham R. Shenoy" , K Prateek Nayak Subject: [PATCH v3 7/8] sched/fair: Simplify the entry condition for update_idle_cpu_scan() Date: Tue, 20 Jan 2026 11:32:45 +0000 Message-ID: <20260120113246.27987-8-kprateek.nayak@amd.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260120113246.27987-1-kprateek.nayak@amd.com> References: <20260120113246.27987-1-kprateek.nayak@amd.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: satlexmb08.amd.com (10.181.42.217) To satlexmb07.amd.com (10.181.42.216) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BL02EPF00021F6C:EE_|SA5PPFB2BF91BC0:EE_ X-MS-Office365-Filtering-Correlation-Id: 75e2ef93-509b-445a-8a56-08de5817fa4f X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|82310400026|36860700013|376014|7416014; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?QIVVZvQJnC/plHHjXWkedhbc2uybEgvKop8mU5Y7HP7neMs0QCNxfCAMDlVq?= =?us-ascii?Q?Fizeix8S3bVTcO5rxQ+ORSjq3pMHjaUmzWYLkfh8z3RRlu7muGslJGAV2JEs?= =?us-ascii?Q?dwa7juIigdas4tWltnsCkN+kdgPGoDqYKclS8qZ4AoJBGy19+pcha7xHyP98?= =?us-ascii?Q?GtDQg5h4qmvQ/Aa9B9FH1NI16QY5FPNArH0YLnZ9dAN4Iak5YJ9aUoMPPEWZ?= =?us-ascii?Q?pvRwtpyVhcLzm2I+awGyZ79A/jdKh3JChLDpogU0bNcp0oWwdd96XmNzklom?= =?us-ascii?Q?2g06FWBEZ9IdiUeBovGnaM/mt2Qk+sT/7+egrQBXiJHabDpDP/uhDamxKkwh?= =?us-ascii?Q?6eDwmlapYfS8CBNYt0Z9qhw+Ze5y1FtzeIrxJ3YYe6VP5ChL20HDh77FKsJK?= =?us-ascii?Q?MHq4fa3UMaspdb6+q/3vnGTgxDaRN7u26EThvD6SCaqdwhZdtrr95bi54Xcy?= =?us-ascii?Q?LqzJbwwwIbAT2lVW4c1gaCW5GgYnhffx58jUErV8Cnwec+x5HHFhiG1qwHB+?= =?us-ascii?Q?nBJpHD89EdFmSyhnYGZPOJbS40U32xvuKQD8DV44AYE7SiiOYmF0FDhafug6?= =?us-ascii?Q?qt0unWkSq9uMVIkahh1KnexZyoK/+vF8d/xMbrV2Hgp5W3gJkNAzyJlxWHut?= =?us-ascii?Q?9qyGfXi4SKtoMvXx7vEKoYLqxh3cH3jqtV0ygjtxZlzB9qm6c+BVnPHrOHf7?= =?us-ascii?Q?2XQURb/xbRIxLTG9XY24ndb53ULsD6h5T0vVeF5yfR8+IQpsi9qexbPG7KKM?= =?us-ascii?Q?Buk5GIy2zhbhfy2BcPbS5inO8GXcJuuYN09/MjkkagKMs24rKro9LyBDVbyy?= =?us-ascii?Q?X4sYdnZxMXefOJ12RrkWgiwhZnfVaXXUqS2ZzUgA7q4HU0C1BeviYbMgm9ky?= =?us-ascii?Q?UtbHizvxEtRsUeFLs5WmQbvd4UaDWEfVxDQ0TOJmrahqMlag1jDyG5ivIE1P?= =?us-ascii?Q?/tJ6ngoDDbY2zv6fV7YBC1mY5ieWWMRnzovRZ3jElGMoLLsOui/ai3Anu8Mi?= =?us-ascii?Q?YwSGWSdQk3xKovK8QUg52Pq8qptF84dBvAYiLRIpLHX/DGw41F5SxD84xb1g?= =?us-ascii?Q?KLnFtanIVuO5c2+1Z9S1AIW+li0TKdyL3s1bVCq6dBZSkcm9OVGZwOuwGpeT?= =?us-ascii?Q?blv3tN6tqWhapyvlKoshE9UouptUgsJoBvY5mtylqDy+2eTwie6bLeBR5HaG?= =?us-ascii?Q?HUmA36t+4SsgN2hobcXd9zkyDVjIGMmoBjbsXqVThY9zDF3IwUPrx9m/o+y9?= =?us-ascii?Q?M0fAmEvUXCsMyR69l9uEkfzjYMVqSIHJ7Z2R7CbdLiREgvuHRgZ90qkaEp80?= =?us-ascii?Q?Bm8YtTvqrJYakxvDxLXETDmo0huKozoX1YZltWsPYI+C/KDsqUD6Iw5CxVzh?= =?us-ascii?Q?yJoscp5xjA8rZSx7pmTkdXBl6P3djolpOV/WSBLBylAEczh6oZLE5FoM4/e5?= =?us-ascii?Q?Z6mRzE1GNlsjSm9+fDQYI0VXdXF3qr51V5+/xwg7FAJD9qeL2eNQmmRB9+IQ?= =?us-ascii?Q?hoXsmWxt7havttXzo+Ywq3A5iXCG7YrScZZl6hTSUQ5En1UjwnhkSd/Uyc/h?= =?us-ascii?Q?wSq7NDvE3NYRhtWFL3ididPcAt9z27DHieF8aNYs3AbI/GGPrSTnFYWVegrx?= =?us-ascii?Q?6ddjP16WTByS23GuQGvLCqx3IBMZXFqPUh87oF+Nlvcgd2HywupeI0LEzbjS?= =?us-ascii?Q?BsscEA=3D=3D?= X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(1800799024)(82310400026)(36860700013)(376014)(7416014);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jan 2026 11:35:13.9761 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 75e2ef93-509b-445a-8a56-08de5817fa4f X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BL02EPF00021F6C.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA5PPFB2BF91BC0 Content-Type: text/plain; charset="utf-8" Only the topmost SD_SHARE_LLC domain has the "sd->shared" assigned. Simply use "sd->shared" as an indicator for load balancing at the highest SD_SHARE_LLC domain in update_idle_cpu_scan() instead of relying on llc_size. Signed-off-by: K Prateek Nayak --- Changelog rfc v2..v3: o No changes. --- kernel/sched/fair.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index e4f208c44916..c308c0700a7f 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -10996,6 +10996,7 @@ static void update_idle_cpu_scan(struct lb_env *env, unsigned long sum_util) { struct sched_domain_shared *sd_share; + struct sched_domain *sd =3D env->sd; int llc_weight, pct; u64 x, y, tmp; /* @@ -11009,11 +11010,7 @@ static void update_idle_cpu_scan(struct lb_env *en= v, if (!sched_feat(SIS_UTIL) || env->idle =3D=3D CPU_NEWLY_IDLE) return; =20 - llc_weight =3D per_cpu(sd_llc_size, env->dst_cpu); - if (env->sd->span_weight !=3D llc_weight) - return; - - sd_share =3D rcu_dereference_all(per_cpu(sd_llc_shared, env->dst_cpu)); + sd_share =3D sd->shared; if (!sd_share) return; =20 @@ -11047,10 +11044,11 @@ static void update_idle_cpu_scan(struct lb_env *e= nv, */ /* equation [3] */ x =3D sum_util; + llc_weight =3D sd->span_weight; do_div(x, llc_weight); =20 /* equation [4] */ - pct =3D env->sd->imbalance_pct; + pct =3D sd->imbalance_pct; tmp =3D x * x * pct * pct; do_div(tmp, 10000 * SCHED_CAPACITY_SCALE); tmp =3D min_t(long, tmp, SCHED_CAPACITY_SCALE); --=20 2.34.1