On 10/27/2010 06:42 PM, Gleb Natapov wrote: > On Wed, Oct 27, 2010 at 05:04:58PM +0800, Xiao Guangrong wrote: >> In current code, it checks async pf completion out of the wait context, >> like this: >> >> if (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE && >> !vcpu->arch.apf.halted) >> r = vcpu_enter_guest(vcpu); >> else { >> ...... >> kvm_vcpu_block(vcpu) >> ^- waiting until 'async_pf.done' is not empty >> } >> >> kvm_check_async_pf_completion(vcpu) >> ^- delete list from async_pf.done >> >> So, if we check aysnc pf completion first, it can be blocked at >> kvm_vcpu_block >> > Correct, but it can be fixed by adding vcpu->arch.apf.halted = false; to > kvm_arch_async_page_present(), no? > Adding kvm_check_async_pf_completion() to arch independent kvm_vcpu_block() > constrains how other archs may implement async pf support IMO. > Um, i think it's reasonable, will fix it address your comment. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html