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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: v2u0ljGLiKO+GH6h5uKmyH//sDyianjsH313RWqvVyULFjvcgBa9jtdca/ICCMm2HXqMFIAgggla45Y5V5+Euurc252hj9tPNfickE69n9iOu1fKyFo3lcPoClzkImc8k5aGCcSpDpJqvWKHlvfXcP03mTHxeAFu0YOrsPwfBHneyJUEP3X3rihPZnfMp+HLtUFGZnhaxyrMeubLVO4SWEn6i2okMQ+zUU70bKNQ3NDHCTkSDQ0A97iBLgRm/cqaFlDPPg0aixYyXDhiOeL/Y/JUk3M0j13zifkOVQECYzmQXRbiAwbQVXRsB/RRwyChmRbiqqbpPRfUCKnYsH4lJULL90lKJy2Kc8R98TjLnG5tX38K955NKql3jsm1CwWTWR6jFT5yu81h+R0wyG2a/qyNxv9JJAQnsLQJVuAy1SC6wN1DC3T4quGJiE3ZO1lZ X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Jul 2026 06:29:07.5082 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 4d4a74cd-3f6c-4a5b-bda6-08dee883b313 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: CY4PEPF0000E9D5.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB6533 Hello Christian, On 7/23/2026 11:41 AM, Christian Loehle wrote: >> +/* >> + * For reciprocal WF_SYNC handoffs, prefer the waker CPU when it has no >> + * other runnable fair task. >> + */ >> +static bool prefer_sync_pair_cpu(struct task_struct *p, int cpu) >> +{ >> + struct rq *rq = cpu_rq(cpu); >> + >> + if ((rq->nr_running - cfs_h_nr_delayed(rq)) != 1) >> + return false; >> + >> + if (!cpumask_test_cpu(cpu, p->cpus_ptr)) >> + return false; >> + >> + if (sched_asym_cpucap_active()) { >> + sync_entity_load_avg(&p->se); >> + if (!task_fits_cpu(p, cpu)) >> + return false; >> + } >> + >> + return true; >> +} > > Maybe @Prateek: > What about SMT, would we want to require the sibling to be idle too? I think we should pass the wake_flags to select_idle_sibling() and do an early return there within the (sched_smt_active() && !has_idle_core) block. > I would appreciate a bench sched pipe on SMT result, if Shubhang doesn't > have one I can dust one off, too. Let me give it a spin on my end too. -- Thanks and Regards, Prateek