On 21/11/12 16:06, Alexander Graf wrote:
[...]
>>>>>> +static int cpu_post_load(void *opaque, int version_id)
>>>>>> +{
>>>>>> + CPUS390XState *env = opaque;
>>>>>> + struct kvm_fpu fpu;
>>>>>> + int i, r;
>>>>>> +
>>>>>> + if (!kvm_enabled()) {
>>>>>> + return 0;
>>>>>> + }
>>>>>> +
>>>>>> + for (i = 0; i< 16; i++) {
>>>>>> + fpu.fprs[i] = env->fregs[i].ll;
>>>>>> + }
>>>>>> + fpu.fpc = env->fpc;
>>>>>> +
>>>>>> + r = kvm_vcpu_ioctl(env, KVM_SET_FPU,&fpu);
>>>>>> + assert(r == 0);
>>>>>> +
>>>>>> + return 0;
>>>>>> +}
>>>>> The kvm register sync needs to happen in the kvm register sync function :)
>>>> That would eliminate the whole purpose of sync regs and forces us to have
>>>> an
>>>> expensive ioctl on lots of exits (again). I would prefer to sync the
>>>> registers
>>>> that we never need in qemu just here.
>>> That's why the register sync has different stages.
>> Not the get_register. Which is called on every synchronize_state. Which
>> happen quite often
>> on s390.
>
> Sounds like bad design then :).
>
> Maybe we should explicitly tell the register synchronization which register
> sets to sync, so that we don't waste time getting _all_ the state every time
> we sync registers?
Yes, a level statement for kvm_arch_get_registers would be good.
