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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 8jZByS2WqJvJ9nX0sS7/7b1+qwUaYfUuxgRMtJeCN5Hbs3pdX4oWLvXSDZlrvtyS6L3UlMkDDMSwPEhwu073msARPp8OpmcslAz0fde4yTIqtk+Dp5qycT0xIn8+Z84vUbA3aATeq/qW1WDooiJ35t8YuY0Ly+8EWlZ1jGA6mEDfKTeooUDO1u9NpxcZp11DklwPMWcUl+W3g6byqbmeum5V4WYMpxDzJIOdCnmRLe5vvEY/3XVGMML+B0t5QZNXCL4IQhkZCcdyU1DDH4OEtIApwC7TuUoDoq5UwNbVLBoIkk5af02DoQUDP5KTvq7p8zKiFFZrb5LXYYX8FxcGMxjTCRwvyBQt0NFQqUVay7JlbyS8CA9JBadUeQiFoxgoz3XRev2gpFtyuvPifhGZES9h/lbfXvMs8OUmw5lSmErPrCoUYckCa6j69TcyxcL/ X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 May 2026 06:07:35.9210 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: a11e8196-cfa4-4cf6-4c84-08deb0b5edee 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=[satlexmb08.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SJ1PEPF00001CE4.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR12MB6287 Hello Shrikanth, Thank you for cleaning these bits up! Couple comments below: On 5/12/2026 8:51 PM, Shrikanth Hegde wrote: > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index 353e31ecaadc..b6f9592b31fd 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -1586,6 +1586,9 @@ static inline bool is_core_idle(int cpu) > { > int sibling; > > + if (!IS_ENABLED(CONFIG_SCHED_SMT)) > + return true; I think !sched_smt_active() can also return early here. That said ... > + > for_each_cpu(sibling, cpu_smt_mask(cpu)) { > if (cpu == sibling) > continue; > @@ -12003,7 +12006,8 @@ static int should_we_balance(struct lb_env *env) ... I think the if() above can simply check for sched_smt_active() before calling is_core_idle() like: if (sched_smt_active() && !(env->sd->flags & SD_SHARE_CPUCAPACITY) && !is_core_idle(cpu)) { ... } That way, we ensure we don't call is_core_idle() and the cpumask_and() unnecessarily on topologies that don't have SMT domain similar to how sched_use_asym_prio() guards the call to is_core_idle(). Thoughts? > * idle has been found, then its not needed to check other > * SMT siblings for idleness: > */ > - cpumask_andnot(swb_cpus, swb_cpus, cpu_smt_mask(cpu)); > + if (IS_ENABLED(CONFIG_SCHED_SMT)) > + cpumask_andnot(swb_cpus, swb_cpus, cpu_smt_mask(cpu)); > continue; > } > -- Thanks and Regards, Prateek