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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Sep 2025 05:44:39.3930 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 24e814e6-e6c6-4527-d63d-08ddeb7623b7 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=[SATLEXMB03.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BN1PEPF00004689.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB8561 On 9/4/2025 1:57 AM, Peter Zijlstra wrote: > So this is mostly tasks leaving/joining the class/cgroup. And its > purpose seems to be to remove/add the blocked load component. > > Previously throttle/unthrottle would {de,en}queue the whole subtree from > PELT, see how {en,de}queue would also stop at throttle. > > But now none of that is done; PELT is fully managed by the tasks > {de,en}queueing. > > So I'm thinking that when a task joins fair (deboost from RT or > whatever), we add the blocking load and fully propagate it. If the task > is subject to throttling, that will then happen 'naturally' and it will > dequeue itself again. That seems like the correct thing to do yes. Those throttled_cfs_rq() checks in propagate_entity_cfs_rq() can be removed then. -- Thanks and Regards, Prateek