Re: [PATCH v3 5/6] virt, sched: add cpu pinning to smp_call_sync_on_phys_cpu()

From: Juergen Gross
Date: Fri Apr 01 2016 - 05:26:34 EST


On 01/04/16 11:15, Peter Zijlstra wrote:
> On Fri, Apr 01, 2016 at 11:03:21AM +0200, Juergen Gross wrote:
>>> Maybe just make the vpin thing an option like:
>>>
>>> smp_call_on_cpu(int (*func)(void *), int phys_cpu);
>
>>> Also; is something like the vpin thing possible on KVM? because if we're
>>> going to expose it to generic code like this we had maybe look at wider
>>> support.
>>
>> It is necessary for dom0 under Xen. I don't think there is a need to do
>> this on KVM as a guest has no direct access to e.g. BIOS functions of
>> the real hardware and the host system needs no vcpu pinning. I'm not
>> sure about VMWare.
>
> OK, then can we WARN if .phys=1 and the platform doesn't support it?
>

Yes, good idea.


Juergen