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Goncalves" , Joseph Salisbury Subject: Re: [PATCH] sched: cgroup: Move task_can_attach() to cpuset.c Message-ID: References: <20251003121421.0cf4372d@gandalf.local.home> <20251003124300.4698dd18@gandalf.local.home> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251003124300.4698dd18@gandalf.local.home> X-ClientProxiedBy: MI0P293CA0007.ITAP293.PROD.OUTLOOK.COM (2603:10a6:290:44::10) To LV8PR12MB9620.namprd12.prod.outlook.com (2603:10b6:408:2a1::19) 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: LV8PR12MB9620:EE_|LV2PR12MB5751:EE_ X-MS-Office365-Filtering-Correlation-Id: 4f0bacb5-d031-4593-d323-08de029d648d X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|7416014|366016|376014; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?OtGuVLE39fqRNYGQaXALcWNSzP1RrFDiCEZLs0nIvshxUUh6AL1N/D4Nmxug?= =?us-ascii?Q?2qR4DdodvkaH+dRJ+jEVGznBMbbUqWY+H71hidTmi2tklqhs/+4GlODadp68?= =?us-ascii?Q?VZcsRVDXJZs3pfqAeRQxhWgbniLgk4BA6wtHW4bgP8l7l4JRnvy3rgNsajyK?= =?us-ascii?Q?k+3ezX5zJVm0y17CBgl7MPz30LplQxGdpd1D1ZW87f+b8tGIa7nZTToz5Bp7?= =?us-ascii?Q?KuOqwuuZKowWOvOatPMo+dwWxVb/yXlQHp0HhUh715Emb5eOLSlYIwQGCeDP?= =?us-ascii?Q?0xh5/IYf6YM0asBW6XfA+OgLdPsbkzeu2Tvq4Rd7gGONXnjuSyC5LFyeuF09?= =?us-ascii?Q?bEtHpd1IiWIVrFUHwt2mAWXtwWhsSaBIIj6VCRXqN1+qXpfH0EA6BYpzytYW?= =?us-ascii?Q?oYCl/AxdcziPwxINXbKRaRLdQid6TMEFki/DZYcl5DSqgNushqp7uQS3zqZc?= =?us-ascii?Q?qoe0dOaqO1EAONM5AU8QWdqna/CH6o4XAqFn+vpahy3e+Q0pJ54u8s0C4ewk?= =?us-ascii?Q?6FUpksKasb7ptE1/0YV7eY3TaZbeSDApSuignNAC81TCpzzyfTF9GuLEd1FD?= =?us-ascii?Q?1BXB2h+3i80AWIRkPQiS8IrVlc5v5u28WYW2krB3ri6ufO25pQJ3fpTTgkC5?= =?us-ascii?Q?8GBMnO8OqJmP177MZeetyWUHFFJT6a2SMjtsgoByq9JNQXihElMnMTi/aitH?= =?us-ascii?Q?uy2jcDTUZuuW3cDRKZr5FHLoKXbfDGE5lvPXjSrTl1z/Fih5FgVdzhW1aG+N?= =?us-ascii?Q?3VKLs+ZUPXHovQ6OzDhZWNRVYlOZGhYNuuw7uqUdMRMKeefJKNwjRavriXHX?= =?us-ascii?Q?irPojTzagU6cpXAqBL4Oq6X45mYgSKUyqzMcnhVMuIAibKhkmmnRU6KrVi4n?= =?us-ascii?Q?w5ye4Yv2zaOHfKX7nY2JbeR+akpFdtJzfiK5VBc+QYwc5gLnLT6pm1rcYhLr?= =?us-ascii?Q?qH4M2HTAIHvDanM2P3i0b7f+qJPOyfz7vJYbXWsDeMXDU0gbu4TCWM5c2opp?= =?us-ascii?Q?EMWQ/2t7wFzEzA1gQT6WGwGMQAYP0A+6CkIhtNNqYX/CtsWl45ArJojNEmXQ?= =?us-ascii?Q?1jaNpp32gF8JLaQo5FUbjlmttOBSkNQcdX3kYEvb6QyyuTN9G4ChMVrWvr0g?= =?us-ascii?Q?iXACCS+dmA0IjBZp5LnNxGkTzZsdrpkHvlrsPK57CYjoB24tMkBkX6OM00R2?= =?us-ascii?Q?ItSScAH1ULO/Oq8woWM5YMUBzUkxzXYyDSYC+vEvaXQPI3SGOBzUtokO9M7V?= =?us-ascii?Q?kOxAhEj0k8PtVKIBvOZjh6ZjvF9lieJFbhtOIRWiZQuWSv10BPdkfmGJEHzb?= =?us-ascii?Q?PIAcjpEVH5nn8AzXv82wo+JlSiLpyKTYJ2ca53K7cVtn/KL/YySGcTVd5x9a?= =?us-ascii?Q?jI2+RMfxYVfpHgBqhA+iCuSPVexPCAfJq+sgOKFWUja9JfT8HemGk+vpSGox?= =?us-ascii?Q?MIIHRCKyOlOq3XrJFbzgVJ5X5fDHT0/u?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:LV8PR12MB9620.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(7416014)(366016)(376014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?8QWQ4ulHQdt5ej0hpuQIMXBs1W5Uumo/oGQ0XFCcVHXGfo0Ky3Ha24xppXcm?= =?us-ascii?Q?g9KGIehrzP12rcVHMhfTXlZTBX67eLL3Z4GQwouOqVufiZgx3mMNgRZxd9Lt?= =?us-ascii?Q?yHyIxw7wzPK5wsw+JRE2bOH0UKNLA5Bw465kKeuf/BDLMvDXIi7co8xFh1N9?= =?us-ascii?Q?n12JSUFbJBGZCNTNe64iaWSJmwRWtcVjiOnFkd8ncCa7WH/kCPQI4jQqVw41?= =?us-ascii?Q?JaFHjw89QOoR4P/r5JyqTVkMLC9ZjXS1uulp5NoQOw5C2b1iqSdEJefmqvbX?= =?us-ascii?Q?Gpr587RKfpIy0S3r2srOy+UcLhcBamm9xv+EHPlrBHQAEtZXLCrEC5muiXI9?= =?us-ascii?Q?+GDF6SGc8MJh47K3yWTcaklPnohxeHxWWsgoFOM7QYMN30rUNYbXCnOguikN?= =?us-ascii?Q?t5LuMswVmae4d/OCfJK+VTip62Zk+jnlVuBkwl+3sL9Z8XqkKRFsqVOSjQwm?= =?us-ascii?Q?uLg7ho/q2FIML/hE4T9iLmrzFU5xgIABZ5kBEIU7UWrl8jkzAF7Qch3ecVaA?= =?us-ascii?Q?n9YVBPTkU70VhtFv36xa1+wcNd89dNwwCulxUvuGnChNfIVHvyuywKItr1MF?= =?us-ascii?Q?05d/DHZFylrl1ZM4GqNnP3gVFKRX49ITXLWmy7Fz/iHmv8h23hRllEHuIBeF?= =?us-ascii?Q?4jHE/V0o61tfpW0QTtke3NS/6UpxidyaKml5sbSfT+yGSwo9cCnfKQnvfddP?= =?us-ascii?Q?gpj0++SFt62QVr2Z6pjlpRv85uKSoDnCp/5aObC61XEC36hsZ8+Gyykcts6F?= =?us-ascii?Q?aJqVlJN2G/tf2CKfQB8cWv19ta/67r9ewTDET1xeZ7dtIbRa7d07DuHgPm2Y?= =?us-ascii?Q?X6xEdrR3Y04WM2F4N2RBRY2Ar80PgnrJV+LFePrO6QZ56B/v/14HgbUDYc/j?= =?us-ascii?Q?0BWTrnv97c1z/jAntjA+aUBHNWbec3mwnlZcFlIX2fTCwRWyMyyKcYpFb1oP?= =?us-ascii?Q?hKNGBr7cXcwxG/5U+O5PW8znnjoc8jWQuJy4OdvBZ7+SfeIycrhjIPHQ06nI?= =?us-ascii?Q?vcC1iOvPplqvF5CA4F97ur9I/p/U+V2mq6GzcLcEjU9OrFYjFBukdWn2WFZX?= =?us-ascii?Q?jDOe4AErRU7H1qHLQyVdxIGQuPFRorH3MbOkXccd9GhrOnNDAdJ2r2r1c5HV?= =?us-ascii?Q?uXVvrhKgK4/+iNji8/GeCRZ1duTqR8LXsuLuT1niMAyUpEmBxd5I2GBVrJYB?= =?us-ascii?Q?zM7+itXMmgfS2pOniKbIks9tZG4fGbA7/V8+rd76tf9hYc10/kkyJx0yhJ8z?= =?us-ascii?Q?+tuK7X7uMuMmcJaeUA/eFfq2d4GdiLMNTR+zvoUS5Y66IDXew8JERbBl0Moi?= =?us-ascii?Q?Oedhfc1A3jpYTa4rY97JIMLfJY8FOtI2Lf0qn9ZlhPhPwJT6JK7RhgGTqHef?= =?us-ascii?Q?zMAUEW8JT8vkCRL1yInl8lVXcHd2COee+qU7ZW8lTm0NpNXydQppfQ4JbUEd?= =?us-ascii?Q?tqsC/l0XYKhE5yvDWLwTJz9H9o7Ot6Z+b+bwXXSl32TaZ9BGWya3vks90oSQ?= =?us-ascii?Q?yIbY9vDTSIH8Boilyo5dW0OR32uj+tZKxzYxhRr+wjiIr1SA0uuJfnZFA8Fs?= =?us-ascii?Q?Tu9gXCtWIHy9YkoS93/I8aPTSSspqVbWEYL9cKc3?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4f0bacb5-d031-4593-d323-08de029d648d X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Oct 2025 16:53:35.4584 (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: E9rkk1zjwC4jTyIMRdANJb+SCFOeUJcYdmLhQQGf7F++rAehQrCDowWIDlhhPdIUHa6lrNtpaETIzD1GF0+b1Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV2PR12MB5751 On Fri, Oct 03, 2025 at 12:43:00PM -0400, Steven Rostedt wrote: ... > > > +static inline int task_can_attach(struct task_struct *p) > > > +{ > > > + int ret = 0; > > > + > > > + /* > > > + * Kthreads which disallow setaffinity shouldn't be moved > > > + * to a new cpuset; we don't want to change their CPU > > > + * affinity and isolating such threads by their set of > > > + * allowed nodes is unnecessary. Thus, cpusets are not > > > + * applicable for such threads. This prevents checking for > > > + * success of set_cpus_allowed_ptr() on all attached tasks > > > + * before cpus_mask may be changed. > > > + */ > > > + if (p->flags & PF_NO_SETAFFINITY) > > > + ret = -EINVAL; > > > + > > > + return ret; > > > > As we're cleaning up, we could just return -EINVAL and 0 directly and get > > rid of that ret variable. > > That should be a separate patch. Moves should really not do much else. I > even wondered about making it a static inline too, but figured that wasn't > touching the logic, and the function was going to become static anyway. Oh yes, good point. In the meantime, FWIW: Tested-by: Andrea Righi Thanks, -Andrea