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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Dec 2025 03:09:04.3081 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 243bcd9e-5fdd-44b1-0c1f-08de3474cffd 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: BL02EPF0001A0FF.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CYXPR12MB9428 On 12/5/2025 7:06 PM, Vincent Guittot wrote: >> So I was experimenting with: >> >> deactivate_task(rq, p, 0); >> set_task_cpu(p, target_cpu); >> __ttwu_queue_wakelist(p, target_cpu, 0); >> >> and nothing has screamed at me yet during the benchmark runs. >> Would this be any good instead of the whole lock juggling? >> >> Since this CPU is found to be going overloaded, pushing via an > > Just to make sure that we speak about the same thing. With EAS > overloaded and overutilized are 2 different things. EAS don't care and > some time want to overload a CPU( having more than1 task on the CPU) > but EAS is diable once teh CPU becomes overutilized I meant to say overutilized in this context. Sorry about that. > >> IPI vs taking the overhead ourselves seems to make more sense >> to me from EAS standpoint. > > I suppose that it's worth trying the IPI on EAS and embedded device If they are cheap enough, we can simply use TTWU_QUEUE check for the !PREEMPT_RT and use move queued task otherwise. -- Thanks and Regards, Prateek