Re: [PATCH RFC V3 2/3] kvm: Note down when cpu relax intercepted or pause loop exited

[Christian Borntraeger <borntraeger@de.ibm.com>]

On 13/07/12 05:35, Raghavendra K T wrote:
> Yes! I forgot about archs in init function.
> How about having
> #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
> vcpu->ple.cpu_relax_intercepted = false;
> vcpu->ple.dy_eligible = false;
> #endif
> 
> This would solve all the problem.

No, you need to mask all places....

> 
>>>
>>>       r = kvm_arch_vcpu_init(vcpu);
>>>       if (r<  0)
>>> @@ -1577,6 +1579,7 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *me)
>>>       int pass;
>>>       int i;
>>>
>>> +    me->ple.cpu_relax_intercepted = true;
>>
>> dito
> 
> currently vcpu_on_spin is used only by x86 and s390. so if some other
> arch in future uses vcpu_on_spin, I believe they also have to enable
> CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
> what do you think?

...because  this function is compiled no matter if called or not.
> 
>> maybe define static inline access functions in kvm_host.h that are no-ops
>> if CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT is not set.

As I already said, can you have a look at using access functions?