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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?/pfKSNZ4fWlo7aPXKX/F2lKCbmLz/YjZMaY7q7VCvS0RPVRNcI1I3hywJlHm?= =?us-ascii?Q?GorCUWaOIBCv/Ou3l1UDdKh6BGhRjM1XJ9EF5PzTOPo8mvcsft8NqW/wF7aF?= =?us-ascii?Q?/P3wGT/BPMfljOzl6sjV+ffFDY2KCc2v5SSB7ftfwN9sgRd9GISOYf98wZvW?= =?us-ascii?Q?KkGuf4nm+5RS6S8bSaIddI1eI/8Ct0TmE+2N+QTMUgvcnI11gwee9MK3Cujv?= =?us-ascii?Q?J2/ApnC4pc7PSj522M387M9zuHLc4r+EE//KDfXVQwVit6UDnQjcIIj62x+k?= =?us-ascii?Q?+1DkpJNOq4WCoRJPNUbweoRzDj47vcGS+B5pfFeOu7v+6kljOp+MbsB9qR07?= =?us-ascii?Q?Sf8jT14aoWSIUqcTXljDLmhcxp6hSJvA3qhAI1pC8Zw1z3g9yEafylTn9Upw?= =?us-ascii?Q?/Kj3xPseuOUN0AHtR11DNSnpqLl1jiScffo5JIUNS58wGRAXmsYWEhb/DWqc?= =?us-ascii?Q?h/PBySB7cix0q1lzaQG8Unm7QCbV+BEeeagelRIrVpctYrvor4CGEu5Lofcw?= =?us-ascii?Q?qWMce7bCb38WlXLA4cose/oWoHnbpPj/ThuvM+Ur+tbjdHVENf9Cwq5clfdM?= =?us-ascii?Q?obd5TginlhSXBNRg1ljBkBDVDclkXzaNUwhQfT+kkVNiJJ+MrIEZ8HTmyi33?= =?us-ascii?Q?k6q/MIApf0ujep4gkgp3B0pfdHMfL78KdfoHLQv03xrmajTvV26CW10c9SGs?= =?us-ascii?Q?Xu01yNGIGitjjBngGBdV7Izz5mkr/FG9Fx6l24nhc8rF504FQUgXtoUTi+KU?= =?us-ascii?Q?gsJViUfCPjLNmcomJmHCozxMvCl/7xC4MyQJbXr7OJ+Nb3DBayX2O8vUbvN0?= =?us-ascii?Q?aSElA6f/V2S0vwyLt8CEPRERtr7joFytflF+8fVkA/AWBibH0XMK4fxEa5f6?= =?us-ascii?Q?1PgzjLD9UHlxDJDYYITJtgXt1Fv29i3EqpiOKEjjz1RMOuov1bANhpMkJEAU?= =?us-ascii?Q?sSZWzJzp0qAJmgiu76sQmvqhUu7q6wlIxsL5MGG2ZGDIDaR09rebKKexQD2q?= =?us-ascii?Q?GFq9o0Z14tGLK4nBgKQeahGp+QuJ/3RS77NB4j2UozvhZswmCf/IhABg4W75?= =?us-ascii?Q?7DBPPbxeToXO4dcnZ0kzApqLuYE2WTAOGGlMZDuU/XkGdDSsW8MEPS68Aar+?= =?us-ascii?Q?izwZK4OXqLZauUFEQwltO54YcmMhYdfEJmClta8kK4opXwBtaQXxwdBpjSAX?= =?us-ascii?Q?C/8HJOrkIIBj3zkcSyBNjrrFZXZSsy1dbHtcVGl75p34CGsZoJnwzvGLVubI?= =?us-ascii?Q?87rgQjTzh6I33pBkz657zrCekgrRb0c9rZpEUVVbzanPBlHCJt6ojSjdrjuC?= =?us-ascii?Q?1+HUPIgEEOFStTU5HzGxFJsukSCNXDJMeds+ma0nP5GhHw+vKpRcLcrkwWnS?= =?us-ascii?Q?JCpGV/xaa7NCUO8nK8skQt3clETWgt87LxvCDcKVWNQ869mOIgzNP4o/iZzI?= =?us-ascii?Q?H6TnG5LhynTD7LzNJazwot8CGPIb5K+N5lI1TZSrWHUNzyDVwI6dxdTOLJue?= =?us-ascii?Q?tg7w2PIn19EXG9wjSKyG1b7xluSkFjFqKPbJ949IIkpAD9fg3TpD5CLnABbw?= =?us-ascii?Q?aMHXVrM5tbPaqHRn1cZ66e839W4ZFdUMJ1L//DuA?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c9627131-2c1d-4791-9915-08dcf25aeef8 X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Oct 2024 05:32:35.1408 (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: 3gg4cp+dR33i20JafWX3BjNJFGK2BuBI7qAvjauB70DItHE6TJbCb3+5Evugwo+3n6dIEMTTu6yMcnRZ9BNSng== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY5PR12MB6455 On Mon, Oct 21, 2024 at 10:01:27AM -1000, Tejun Heo wrote: > External email: Use caution opening links or attachments > > > Hello, > > Overall, I think this is a great idea. > > On Mon, Oct 21, 2024 at 09:13:04AM +0200, Andrea Righi wrote: > ... > > + /* > > + * Determine the task's LLC domain. > > + */ > > + sd = rcu_dereference(per_cpu(sd_llc, prev_cpu)); > > + if (sd) > > + cpumask_and(llc_cpus, sched_domain_span(sd), p->cpus_ptr); > > + else > > + cpumask_copy(llc_cpus, p->cpus_ptr); > > However, I wonder whether we can be a bit more efficient here. Always > copying cpumasks can become noticeable in larger machines. It should be > possible to cover most common cases without copying cpumasks - e.g. tasks > which don't have any cpumask restrictions or affine within a single LLC > (including tasks restricted to one CPU) don't need to compute a new cpumask > each time. They can use either sched_domain_span() or p->cpus_ptr directly. I agree, I was also thinking to improve this part to avoid doing the copy. And I have a few other changes to apply, I'll send a v2 soon. Thanks! -Andrea > > Thanks. > > -- > tejun