Re: [PATCH v3 3/5] KVM: x86: hyperv: use get_vcpu_by_vpidx() in kvm_hv_flush_tlb()

From: Roman Kagan
Date: Fri Jun 29 2018 - 11:01:29 EST


On Fri, Jun 29, 2018 at 04:14:53PM +0200, Vitaly Kuznetsov wrote:
> VP_INDEX almost always matches VCPU id and get_vcpu_by_vpidx() is fast,
> use it instead of traversing full vCPU list every time.
>
> To support the change switch kvm_make_vcpus_request_mask() to checking
> vcpu_id instead of vcpu index,

I'm afraid you can't do this: vcpu_id (== apic id) can be sparse, i.e.
it's not very well suited for bitmaps and can exceed the max number of
vcpus.

Roman.