Re: [PATCH] KVM: halt-polling: poll if emulated lapic timer will fire soon

[Christian Borntraeger]

On 05/19/2016 01:35 PM, Wanpeng Li wrote:
> 2016-05-19 19:23 GMT+08:00 Christian Borntraeger <borntraeger@xxxxxxxxxx>:
>> On 05/19/2016 11:26 AM, Wanpeng Li wrote:
>>
>> I think in general a good idea to poll if a timer will expire soon.
>>
>> Some patch comments:
>>
>> Same for all non-x86 archs:
>>> +static inline unsigned int kvm_arch_timer_remaining(struct kvm_vcpu *vcpu) {}
>>
>> A function returning int, without a return statement?
>> That gives at least a compiler warning.
> 
> How about return 0 for all non-x86 archs?

We will provide an s390 implementation soon, but until then a proper
default would be good.

[....]
>>> +     if (vcpu->halt_poll_ns || (remaining < halt_poll_ns_base)) {

but then remaining is 0 and the 2nd condition will always be true, no?