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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Sep 2025 05:23:53.8412 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 0abfbc73-fd64-4e6b-507b-08ddf0f36635 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: CH1PEPF0000AD75.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA5PPF37951B1C9 Hello Shrikanth, On 9/10/2025 11:12 PM, Shrikanth Hegde wrote: > @@ -8563,7 +8563,7 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int wake_flags) > if (!is_rd_overutilized(this_rq()->rd)) { > new_cpu = find_energy_efficient_cpu(p, prev_cpu); > if (new_cpu >= 0) > - return new_cpu; > + goto check_new_cpu; Should this fallback to the overutilized path if the most energy efficient CPU is found to be paravirtualized or should find_energy_efficient_cpu() be made aware of it? > new_cpu = prev_cpu; > } > > @@ -8605,7 +8605,12 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int wake_flags) > } > rcu_read_unlock(); > > - return new_cpu; > + /* If newly found or prev_cpu is a paravirt cpu, use current cpu */ > +check_new_cpu: > + if (is_cpu_paravirt(new_cpu)) > + return cpu; > + else nit. redundant else. > + return new_cpu; > } > > /* > @@ -11734,6 +11739,12 @@ static int sched_balance_rq(int this_cpu, struct rq *this_rq, > > cpumask_and(cpus, sched_domain_span(sd), cpu_active_mask); > > +#ifdef CONFIG_PARAVIRT > + /* Don't spread load to paravirt CPUs */ > + if (static_branch_unlikely(&cpu_paravirt_push_tasks)) > + cpumask_andnot(cpus, cpus, cpu_paravirt_mask); > +#endif Can something similar be also be done in select_idle_sibling() and sched_balance_find_dst_cpu() for wakeup path? > + > schedstat_inc(sd->lb_count[idle]); > > redo: -- Thanks and Regards, Prateek