Re: [PATCH] RFC: Create kvm_arch_vcpu_runnable() function

[Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org>]

Carsten Otte wrote:
> Avi Kivity wrote:
>   
>> What about merging kvm_cpu_has_interrupt() into _runnable()?
>>
>> My feeling is that we can keep it separated.
>>     
> On s390 there is a difference between has_interrupt and not runnable: 
> CPUs can be in stopped state, and they can be in enabled wait (enabled 
> for interrupts, similar to hlt state on x86) or in disabled wait 
> state. All those states indicate that the CPU is not runnable.
> Interrupts on the other hand are typically floating between all 
> virtual CPUs and can be accepted by running CPUs only (that is either 
> running, or in enabled wait).
>
> I agree that we should keep it seperated.
>   

On x86, running hlt with interrupts disabled is similar to your disabled 
wait.  Interrupts in general are directed towards a specific cpu, though 
older processors supported round-robin or priority based dispatching.  
With extensive caches this is a performance loss, so the feature is not 
missed.

Thanks for the clarification.

-- 
error compiling committee.c: too many arguments to function


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