From: Li RongQing <lirongqing@xxxxxxxxx> Check whether vcpu is preempted or not when HLT is trapped or there is not realtime hint. In other words, it is unnecessary to check preemption if HLT is not intercepted and guest has realtime hint Signed-off-by: Li RongQing <lirongqing@xxxxxxxxx> --- arch/x86/kernel/kvm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 1cceac5..1a2744d 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -820,8 +820,10 @@ static void __init kvm_guest_init(void) has_steal_clock = 1; static_call_update(pv_steal_clock, kvm_steal_clock); - pv_ops.lock.vcpu_is_preempted = - PV_CALLEE_SAVE(__kvm_vcpu_is_preempted); + if (kvm_para_has_feature(KVM_FEATURE_PV_UNHALT) || + !kvm_para_has_hint(KVM_HINTS_REALTIME)) + pv_ops.lock.vcpu_is_preempted = + PV_CALLEE_SAVE(__kvm_vcpu_is_preempted); } if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) -- 2.9.4
