Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

[Vitaly Kuznetsov]

Paolo Bonzini <pbonzini@xxxxxxxxxx> writes:

> On 27/09/2018 13:07, Roman Kagan wrote:
...
>> 
>> I must say that now it looks even more tempting to follow the same
>> pattern as your kvm_hv_flush_tlb: define a function that would call
>> kvm_apic_set_irq() on all vcpus in a mask (optimizing the all-set case
>> with a NULL mask), and make kvm_hv_send_ipi perform the same hv_vp_set
>> -> vcpu_mask transformation followed by calling into that function.
>
>
> It would perhaps be cleaner, but really kvm_apic_set_irq is as efficient
> as it can be, since it takes the destination vcpu directly.
>
> The code duplication for walking the sparse set is a bit ugly, perhaps
> that could be changed to use an iterator macro.

I actually like Roman's suggestion on how to re-write kvm_hv_flush_tlb()
and I also agree that it would be easier for future readers if we write
kvm_hv_send_ipi() in a similar way. Actually, I already have v7 in my
stash, will be sending it out shortly.

-- 
Vitaly