Re: [PATCH 3/4] KVM host implementation
From: Peter Zijlstra <peterz@infradead.org>
Date: 2021-08-31 07:16:42
Also in:
lkml
On Tue, Aug 31, 2021 at 09:59:18AM +0800, Tianqiang Xu wrote:
quoted hunk ↗ jump to hunk
@@ -4304,8 +4374,14 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) idx = srcu_read_lock(&vcpu->kvm->srcu); if (kvm_xen_msr_enabled(vcpu->kvm)) kvm_xen_runstate_set_preempted(vcpu); - else + else { kvm_steal_time_set_preempted(vcpu); + + if (get_cpu_nr_running(smp_processor_id()) <= 1) + kvm_steal_time_set_is_idle(vcpu); + else + kvm_steal_time_clear_is_idle(vcpu); + } srcu_read_unlock(&vcpu->kvm->srcu, idx);
This cannot be right. The CPU could long since be running tasks again, but as long as this vCPU crud doesn't run, the guest keeps thinking it's physically idle.