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charset="utf-8" While rebuilding a sched-domain, arch_update_cpu_topology() is a way for the architecture to tell the scheduler that there are asymmetric CPU capacities that need to be taken care. If arch_update_cpu_topology() returns non-zero, then scheduler shall rebuild the topology post scanning the CPU capacities. On Powerpc, If there are soft-offlined CPUs, then inform the scheduler to scan for possible asymmetric CPU capacities. Signed-off-by: Srikar Dronamraju --- arch/powerpc/include/asm/smp.h | 3 +++ arch/powerpc/kernel/smp.c | 8 ++++++++ 2 files changed, 11 insertions(+) diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h index fe6315057474..92842eda1a03 100644 --- a/arch/powerpc/include/asm/smp.h +++ b/arch/powerpc/include/asm/smp.h @@ -269,6 +269,9 @@ extern char __secondary_hold; extern unsigned int booting_thread_hwid; =20 extern void __early_start(void); +#ifdef CONFIG_PPC_SPLPAR +int arch_update_cpu_topology(void); +#endif /* CONFIG_PPC_SPLPAR */ #endif /* __ASSEMBLER__ */ =20 #endif /* __KERNEL__ */ diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index c269b38dcba5..478847d6ab7c 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -1827,4 +1827,12 @@ unsigned long arch_scale_cpu_capacity(int cpu) } return SCHED_CAPACITY_SCALE; } + +int arch_update_cpu_topology(void) +{ + if (is_shared_processor() && !is_kvm_guest()) + return (num_online_cpus() !=3D cpumask_weight(cpu_active_mask)); + + return 0; +} #endif /* CONFIG_PPC_SPLPAR */ --=20 2.43.7