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McKenney" , Metin Kaya , Xuewen Yan , Thomas Gleixner , "Daniel Lezcano" , Suleiman Souhlal , kuyo chang , hupu , References: <20251030001857.681432-1-jstultz@google.com> <20251030001857.681432-6-jstultz@google.com> <90e556a4-59d3-4be4-b4a8-5e7ef4b523d1@amd.com> Content-Language: en-US From: K Prateek Nayak In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: MN1PEPF0000F0DE:EE_|SJ2PR12MB9190:EE_ X-MS-Office365-Filtering-Correlation-Id: fac70e3f-387e-4779-e636-08de1830aed3 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|82310400026|36860700013|1800799024; X-Microsoft-Antispam-Message-Info: =?utf-8?B?bDFPb1dTakNyWGQ3SVFjVEZKaDUxbXFFSEZleWVkMFZGTS9renlvUVZ4YjNW?= =?utf-8?B?aUtheFZvQzVlejNLTlYzT0tsbnBWNEtNeFRBbDUyMmhtN0V0cWFkWHUxY0Fl?= =?utf-8?B?anB2SmlNSDFVQlY3cnNmWHRuQ0JIUWdQUllIOUkvb1h3d3JJYVZkakR6QlM3?= =?utf-8?B?R25NcjRDanRIWVNtL2dtTHd1aC9yTUdXOTA2bFM3TGhwcHBleW1WWDRIK1JV?= =?utf-8?B?ZVNPelJTb3dTR3llQ3VBY2hRcis5S1JVMGdFOGJPeUx6bWNQSFIyc0dqWXVs?= =?utf-8?B?c1pheU0wQVQvaTZjUW9iMmh5SVNkTzVTb0UwSmhCRnBVNEV5OHBXT0Ficngy?= =?utf-8?B?TjVGQmVROGVWUWFBbTlNeS9LR0tYU0RQME10a2FXMWRrRVhUeU5Ua1dYaHov?= =?utf-8?B?ekM5em5lUUt6Mjlpdyt3eUU3UVQ5cHdGSytqa3liSVNOUkUzU2J3ZmFSSEIz?= =?utf-8?B?SHZRWndNdjZjV1V3L1VwUmt6d0Iyd1ZNYU42WXRpSWVRSmYva2NZLzVpcWVQ?= =?utf-8?B?RDRUZ3ZkenFma3FvaDhhcXBnV1pRM3l5dmxGY2ZuTFJaaS9lS1JhZ2c2VlpB?= =?utf-8?B?MExwSEV2cVNSMU56L2pXQmg1N01URHVQVjZtcmJPRWFWTEtRQ3VTZjhodW1J?= =?utf-8?B?OUlsQlN6M3FUT1VaVGgvT2Qvaml0aVZlUnZJZktsT2tqc2lnMk83NHdYYzhB?= =?utf-8?B?dTZlTmMxY2lsL1FlOGhrMUJIVlJINk9udXNOWVE3OHhXaTJFSFVJaDcxdU1S?= =?utf-8?B?alJ0NUk5cytRZFFPYjFHUUNCT1dibzVwTC8wSkVHRHUyZEwzd1BFMWJVaGkx?= =?utf-8?B?Sm40YUxWVm5CbnZFSkQyOHVzdDgzNXZnNlVsMzVLUXlrUGdzL3pPSzR4TEw2?= =?utf-8?B?cDJMdzFHa0w2U3haeXdFYTNZai9PNmdGalZoR3VGK0pFeG43Sk45MFE3M0sv?= =?utf-8?B?U0dWSUpLVCtYTC8yRWIrSCtYWGVKVzRZZU5hMnFVeStzUG1UQzhqVzlnWnhQ?= =?utf-8?B?SG5TWnJNSHQxMTJ1KzZJWXB0WmNHYnhrSTZLU3ZJZ0dQTlZ6dVVDUFc0eTdO?= =?utf-8?B?M2V4SEJxOC9DVVJsT2V2VURMbmRHaFJwbEFDRWFoQVRveEtQd3I4QmpORUVC?= =?utf-8?B?RWRNM2NvWXFWY3ZhTGZ2cDI4YW8rMjNHajFIbjJlc010UG9SRTE4aFFSV25w?= =?utf-8?B?Y2hqNWhKc0tIQXlzbnA3OU1hRXBlR3RKQ0dJa2tBMldIREZhMmoySFpTVlNV?= =?utf-8?B?R0d1WUk4NjhxK01jdzVaMkh2SWNuUWNtTGJJN1ZrQzRhQmpwMk1uK1hhd1Rx?= =?utf-8?B?ejBqNnJ0VWREYWs5NE55c0RDME5aenNXU203ZXI2RmU4M1dPQnFacnZiQ1Bm?= =?utf-8?B?L09MbXJqMXZnVFJWN0grOFlQK1VnKzRIY0NTNU13dWM2MHhxbTFaNHR1SjAy?= =?utf-8?B?bXg4bDB6ZFVWVjZDbUw0U0RGSzlZRnl6RFNOVm41bGNuZVVoZzJTNTFueUhz?= =?utf-8?B?ZmVFNUIrenVjc1JkWjc2eHhENlg3ZUgrUExCRVNzQURjM3lRSEpnM3Z6Q1dr?= =?utf-8?B?Y1lXUjFpQlcrTUEyNVNTOWFqUGZGK1RDdEZuVTYvejIvT1VNRGJqbnFYcnUv?= =?utf-8?B?cFFPL1BNMkFTTXFwc1JhZ0MydDBJTnB2WlFTNm1uN2YzVkRiMjNMUkxVMmQy?= =?utf-8?B?N1EyT2lLR1F1ZFBGTW1rb2VpZlRZcGRFclFtNTVJWFMyMkJsd3RVWW5tZ3ZY?= =?utf-8?B?UStqdllqcjh6SVFmcnliMUo5aW9NeFlCMkY4Q3pEbDBwc3hqZlBxOFlydkhH?= =?utf-8?B?dmtrd3d2TnRxSXVtMi9hSXhURC9ycFRlQ2xKVGlEcWdEcEVCcTliWEVOclAr?= =?utf-8?B?NE5QUGNlU1YzNDg3MEVjdXZRdjd2TXQ1Z1V1Y0xlWEtTUWxUNWR3THhpZ0tF?= =?utf-8?B?Z292L2VkREFQQXk0cjJaN2FZNlpQUVdaWTZwajdMU2o1dVlsUjNNQkZtd0JM?= =?utf-8?B?OUFHS1R0Qk1PelFBNEx6U1pKb3VVZHM3UmVkK21aamhBZ203K2dIZmNucEI2?= =?utf-8?B?aUl2YTJ2K2Y2OGZuTFJXdUtmWnFHSGlwWnZUOXNuYVhCamVscWRmOFN3NzVv?= =?utf-8?Q?tvVY=3D?= X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(376014)(7416014)(82310400026)(36860700013)(1800799024);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Oct 2025 03:50:50.3521 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: fac70e3f-387e-4779-e636-08de1830aed3 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: MN1PEPF0000F0DE.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB9190 Hello John, On 10/31/2025 8:45 AM, John Stultz wrote: >>> - if (next == rq->idle) >>> + } >>> + if (next == rq->idle) { >>> + zap_balance_callbacks(rq); >> >> Also I would have preferred to have that zap_balance_callbacks() in >> proxy_resched_idle() but this is okay too. > > So my initial hesitation here is just we call proxy_resched_idle() in > other situations where we might return NULL from find_proxy_task() as > well. So this avoids calling zap_balance_callbacks() twice. > > But thinking some more, later in the full series we often call > proxy_resched_idle() in those paths where we are briefly dropping the > rq lock and we often call zap_balance_callbacks as well there. I'll > take a closer look at the full patch series and see if that doesn't > make sense to consolidate then. Not 100% sure it will work out, but > worth looking into. I don't have any strong feelings btw. What you have currently works well. thank you for the additional background. I should go back and take a look at the full tree again to get a full picture. -- Thanks and Regards, Prateek