From nobody Sat Jul 25 03:20:11 2026 Received: from BYAPR05CU005.outbound.protection.outlook.com (mail-westusazon11010070.outbound.protection.outlook.com [52.101.85.70]) (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 C26123955DC; Mon, 20 Jul 2026 03:31:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.85.70 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784518309; cv=fail; b=jSDjuL8v4X5zr9IAqypOtsCcRZi7qyq2wBolAQPU4m2E7u+8QJVKI5MGs0C62CnK2mBedK17h1/BDBS/5agve0ZDcGaWFWgxss41kkeEOtWwYrA1JJgMujfAqih8Pn026twRYxXbSMR57RfOZjVP7oy5bLz05Xl9NR8FnmoM+No= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784518309; c=relaxed/simple; bh=DH8ZpYp/Z2DVigMu6wax7QRPajmqv3PT2kNlejAOVDM=; h=From:To:Cc:Subject:Date:Message-ID:Content-Type:MIME-Version; b=WBOLQMWFzt7wLCgkDr+DFk3D+oDDWcddmJW04OGk56x8rDbQzH+0gvqGfltW8U/TVGExwdlHqrS1HImqCA57AVL/+JzD/H7AooyaPHXpqavUBnta/I7jFUz2fQAGdYN2g7lUFK0E4V4GYp+kZsSTkD7wPRQdlUH2HeKXRyJiyXw= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=KtWlKNcN; arc=fail smtp.client-ip=52.101.85.70 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="KtWlKNcN" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=kY4N2k8ZEgR9YxXugOIsvkM+BSry4hNVEFQNZkPPNJA/QCnwO9BOP1j/KPMskaEzNvUJ9Z/QnYjVZ5bd6sKTs6W8jIaffOb2uIy66WnpdKjsmTxXj8UQuDLb/MJGhSI2YPqXfjmLqxeo3VktJexDjBztbmlYikz1uh+929R8MXvItTexUT5lityLDopxDL52WzMccYH6aILLp51KRe7lbYCfisveZMkj54kxQOXVl9vEr7s92GqKiXgJAw2Z+EnXPIuSn5FBKwG2zrTP2/J6VOkCjwQNz4F0LQWvi5sT8MJhTjwcf6KyANBvl9Pje9gBdgqj5sfacZVBIuqwqbSsrA== 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=wP/hLuAJPLX4p9+cOcPCWAojBI5kSd4iz0bJD8QIbkM=; b=Ren5/Fjh2NS7FAY0LFzPaiZGBPZSPIWIH4xM3sBgyuWEq0x0B4+9Uorle5x34lBSyMXvsbWd68lL1Rd2ulDfQIWnSbjM3yAye9IvtFxpWr2vzTnU4WPKzJ2ffx0NzDPhuaMNTbwUsOpj1fU+COXe1KqTsowFWJNkW++yoXsiPv5xMrDQkAcSYHCjRMG2eGorDY0QJkpXTE9Qbct4+cynY5PQtvVpOICvoU6H3J4Kx7X3CJkIMSNjgjZXDSQT4o2OoXoxTI6pKPHC/O1VRR1eW6Hx6JGYAEMzeBgAtvK+Vs+n23eeWj+eD0Quzqc7XwlTkRDphj6Ouid+qkKp7J0BIg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=wP/hLuAJPLX4p9+cOcPCWAojBI5kSd4iz0bJD8QIbkM=; b=KtWlKNcNFaOuviKL2u3z2mvw99jtm/B3UJbhgsDSqnDylHe3egpu0/EF4bT+0GEt7CZ1/NGqxZsEqQwNLjvsZG/F5z3pa4NlnRKgkCKO13TB0xqFp+fbqVlxFBNKnL2yPAeM4pCWRk8k9lFYCClTVLdrCOK5eiMK3tVT46Aqv2vX51plqsnMmbE2u1TnNr8HFnGaE/XRQQ/TZH0cw14NX8n8XOYigVU+6FMoY8JIQXr3QmGDmntsGydyS2KlZE5uCeLs7xtXevXbHKhvbKBcm/6bMaTpGfsKrcYkMwkfw4PHuLq1b2f87buagji722aMT6PRx66gmXGcdplRtZ8z4A== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from BL0PR12MB2370.namprd12.prod.outlook.com (2603:10b6:207:47::27) by PH8PR12MB6940.namprd12.prod.outlook.com (2603:10b6:510:1bf::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.223.16; Mon, 20 Jul 2026 03:31:44 +0000 Received: from BL0PR12MB2370.namprd12.prod.outlook.com ([fe80::86cf:c3ec:2cf5:74c8]) by BL0PR12MB2370.namprd12.prod.outlook.com ([fe80::86cf:c3ec:2cf5:74c8%5]) with mapi id 15.21.0223.015; Mon, 20 Jul 2026 03:31:44 +0000 From: Richard Cheng To: ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, andrii@kernel.org, eddyz87@gmail.com, memxor@gmail.com, martin.lau@linux.dev, song@kernel.org, yonghong.song@linux.dev, jolsa@kernel.org, emil@etsalapatis.com Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, newtonl@nvidia.com, kristinc@nvidia.com, kaihengf@nvidia.com, kobak@nvidia.com, Richard Cheng Subject: [PATCH] bpf: Run deferred program freeing on system_dfl_long_wq Date: Mon, 20 Jul 2026 11:31:35 +0800 Message-ID: <20260720033135.62223-1-icheng@nvidia.com> X-Mailer: git-send-email 2.50.1 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: KUZPR02CA0017.apcprd02.prod.outlook.com (2603:1096:d10:31::8) To BL0PR12MB2370.namprd12.prod.outlook.com (2603:10b6:207:47::27) 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: BL0PR12MB2370:EE_|PH8PR12MB6940:EE_ X-MS-Office365-Filtering-Correlation-Id: 3cbbf1bd-5043-4694-cdaf-08dee60f6b87 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|23010399003|7416014|376014|1800799024|366016|921020|6133799003|11063799006|56012099006|10067099003|18002099003; X-Microsoft-Antispam-Message-Info: 84Q+I2YHtYimjRXSNaEjQJdIAY1MWxSfddtSErRLLItsfNFfaP3ypwuwsnv+MV4PhMYlunqYfbQBGKP4yEjQzqUZMCvXeqzsRxYGvISUauC9w8epjvFro4Nd9i3INN6LwRHwdJrTQ8IzAcxL2+Vx/NA7F0Np75ecrxD0nXftZ9AraOEq1Lti+AZlb+v8FsBSXHPBS5P4N5JIwwEDkpvSxE8FJAetqMTyj+GQRJxRLpDxm+gOXr/v7MBQzDw7EkBMU+U9l2HfYfO9oUTmsxfCWZhnIK9i+Gv+RRUEIwbapUPJY4Oei7FDO0s3/MfZq/PUb3fGJKBuIdsE+38tmypzUCtX6CnBk89LOX4gMWV8gmw2sWmRa6OmB18WKFbV+un/4jMpEq+fshvzxyaDWyo7xDTUGo/DxLso4BAR+RDOP4R4obuB31YBa30GDGz/YSzMWVDZJJztgXx+5LcMUasp88RVTulThLjtb0sRKwBHMHFbT6Sa0sxzGrj+q75aG4qrBgMjDVQSXvMz1ygKIX2FzkhZtlsIISVgfbCn9DuKvxJXq/P3ZS/RkNkPTNYVonUK+ZFs10IsCePamjEKHvwH22BxJwxRTh59hQiiKyEvhSOeN2fhsKQTjpbmbBtSi8NvSuKnAH2f/yuSfSGO/esFcf1w1isZ7gEXOGsxA/pMxRe0Mol1hrsZY1RqTg0f6ugbWBHn1XnTY3+XNMPKk/mbbQ== X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BL0PR12MB2370.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(23010399003)(7416014)(376014)(1800799024)(366016)(921020)(6133799003)(11063799006)(56012099006)(10067099003)(18002099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?To9H1dAsurHNe6YWXIouahSAfhPeb6xNQYA5rHqk+Qqs4U6aumjBJefzQiTh?= =?us-ascii?Q?mhMIpIfVRpjNKVnbXrWFhtu1dZYjoQY93SsR766mk17E6wujxp9fRHzWLm4b?= =?us-ascii?Q?kgbQq64JYyKozf+KW4+8B0h9gHbpRNhD77GNh4ANO++fm2CyMx59JkjLTv+X?= =?us-ascii?Q?EdyKXcMQrxsnwXxzeRDHAV2B+R3Ju1gzxxY1gUvigCQ7YrgQK29VNNgHh7E5?= =?us-ascii?Q?19/fxjSF+RqNeVIMe9g9Kz8iHaMdSryMKzXPo2zFTO9pMjDLWbY/wHo5zRjY?= =?us-ascii?Q?ejx724HU2wQ8wXIuhesdShhg+SyUHKN+UthVKByf/Q7wTGvXq0ro2IRU9aAj?= =?us-ascii?Q?EusOS9L1jqabsRdEF9tO9kS3ibWn9LGPHvyDzXV9RkrFkgX288JJ6Acxylgq?= =?us-ascii?Q?qJ4HUoqkDeTBPMxxPKluDEOlY1vPNwRIgDSnw35V1BYlU6Uk3lsoFXqHYlaO?= =?us-ascii?Q?NPKKAK8JnGpzk8Ka7p0ZbRc4IFUbazxWMUVdgV3r8gO2EJx59tkYWkQIB7j9?= =?us-ascii?Q?aPU552eOv07L3e+aAWan+GUs6N5YZIvw/72uBJTA86+zDUE/dn0ZWwtfRpuc?= =?us-ascii?Q?OL2YU3NxRRZHSFU8EM+T1inawFEUEOPbMA9RBSz49Bd1FiAqCtvLSwi/y2QJ?= =?us-ascii?Q?QNbYNpNkKOs4V7xtLGyn8v3gKxcT042jXa+Z3kSIMdEK3/eOdmuF0gzb6F8u?= =?us-ascii?Q?gayf14Dp2y5ra1VyeWmfn50S0qhqjUZp51Ha7HGP+rKdSnJ4YCkwcdR1QTVM?= =?us-ascii?Q?9qrI6cO2a6BLE8dazUDQAJz8MNvPb5EcKe2djVFvHVj6YCY8wYrbjXt6PNDs?= =?us-ascii?Q?yHgC9l7uwzjzGG4dna17+bM18LoqJqkHixCwiaGwdgfnwyJCcg7LKCpQaMwY?= =?us-ascii?Q?QpsawE2RjfmnzNpqZnnuzqUOffsorS7xGev8dG2rePuT7KTJWNEAMfMBRB94?= =?us-ascii?Q?IBSNnJVUh/jEAZjy6c1V8aS+y8ZCN5xmdvxbmmvGjykblN4qC7OHidR8FigV?= =?us-ascii?Q?VAue2cn2381+qjw9i2rqZk8Ka5gTPfOD+h9ULiABst0ad039Kuyg1j8ZM1aY?= =?us-ascii?Q?GVmp7z4oCkzBFsONMyYPVOHq2Duvv9jbOJFxmVFuknSvjdEacrrX8lqgW9+6?= =?us-ascii?Q?oAbVvJSQ5DZzEyhxeg0RXQIsUUkVtHlVkzA5Q6XEBdnYTM/AlGop5gxnDbUH?= =?us-ascii?Q?WzAV2FRFMj9UMPJZ+NBDWqcGsy9couloX8KISP3cSDj+LA7gtWUfbdhNeOIK?= =?us-ascii?Q?JtqDbjjaMIRPB0v8ovuJsbyQyV20pPcTWwDA22IdKPAKGvu6XG8C6cwOwbGR?= =?us-ascii?Q?rpNV+JIel5uwoQfnW5yO9nOg4mmnw9ZvMUlfpmtPA96+PWB2UWe6u+eNsEvm?= =?us-ascii?Q?esTsR6xwdit5/WGVga0AdGX9PlCiYrdtaYK/R69PLaCjsZJuAPfLfmM2MeRY?= =?us-ascii?Q?GHq7HylzECydnNjWtN+C60wfTOk87kcW2rgtZAOEG6Iuz4V1ZyXszQ44hnO3?= =?us-ascii?Q?NXJRVPCO++nTO5lHK+Q0rvi6WGB9oO5Smb6SD96+MoiJ7dHMB36RJLCDpyha?= =?us-ascii?Q?Jbvl9vCQ3De9D1S4fxn/QeE+EnvL+OtM1pGyXiP/46kr9vQpHJGmlvua0QES?= =?us-ascii?Q?7ojvpBah2EAJSgh6PoeC38QRPafGhxYqev5GZct6BO4NUQ0KrrvxLz5l5oER?= =?us-ascii?Q?B2tm/bXUswA7OA5xWo0kva7j1dGUfLDG/TxkLkoXIR7IycKq25FtXO0IQwUg?= =?us-ascii?Q?9ETWYxxQ5g=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3cbbf1bd-5043-4694-cdaf-08dee60f6b87 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB2370.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jul 2026 03:31:43.9460 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: dWy5TGbIEagAnOdHlN1AXqmxuWF7GkAlyuVXAM1QKVvJcG4TdmNcZwxn58labqHEY/Dv3rZYZ+DZu5ZITZlSNQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR12MB6940 Content-Type: text/plain; charset="utf-8" Destroying APT's seccomp BPF programs can spend over 20ms in arm64 JIT text invalidation. bpf_jit_free() calls kick_all_cpus_sync(), which is especially expensive on system with many CPUs. schedule_work() uses a per-CPU workqueue, causing: """ [204351.169849] workqueue: bpf_prog_free_deferred hogged CPU for >20000us 5 times, consider switching to WQ_UNBOUND """ This is triggered during a normal "sudo apt update -y" Queue the cleanup on system_dfl_long_wq, the unbound queue intended for long-running work, to avoid delaying concurrency-managed per-CPU workers. Signed-off-by: Richard Cheng --- kernel/bpf/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 6e19a030da6f..a2ca6bdfb6f5 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -3115,7 +3115,7 @@ void bpf_prog_free(struct bpf_prog *fp) bpf_prog_put(aux->dst_prog); bpf_token_put(aux->token); INIT_WORK(&aux->work, bpf_prog_free_deferred); - schedule_work(&aux->work); + queue_work(system_dfl_long_wq, &aux->work); } EXPORT_SYMBOL_GPL(bpf_prog_free); =20 --=20 2.43.0