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charset="utf-8" load balancer for fair class looks at sched domain and active cpus to consi= der spreading the load. mask out the paravirt CPUs so that tasks doesn't spread= to those. At wakeup, don't select a paravirt CPU. Expect minimal impact when it is disabled. Signed-off-by: Shrikanth Hegde --- kernel/sched/fair.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index df8dc389af8e..3dc76525b32c 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -8563,7 +8563,7 @@ select_task_rq_fair(struct task_struct *p, int prev_c= pu, int wake_flags) if (!is_rd_overutilized(this_rq()->rd)) { new_cpu =3D find_energy_efficient_cpu(p, prev_cpu); if (new_cpu >=3D 0) - return new_cpu; + goto check_new_cpu; new_cpu =3D prev_cpu; } =20 @@ -8605,7 +8605,12 @@ select_task_rq_fair(struct task_struct *p, int prev_= cpu, int wake_flags) } rcu_read_unlock(); =20 - 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 + return new_cpu; } =20 /* @@ -11734,6 +11739,12 @@ static int sched_balance_rq(int this_cpu, struct r= q *this_rq, =20 cpumask_and(cpus, sched_domain_span(sd), cpu_active_mask); =20 +#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 + schedstat_inc(sd->lb_count[idle]); =20 redo: --=20 2.47.3