Re: [PATCH 6/9] KVM: x86: Provide paravirtualized flush_tlb_multi()

From: Dave Hansen
Date: Tue Jun 25 2019 - 17:40:51 EST


On 6/12/19 11:48 PM, Nadav Amit wrote:
> Support the new interface of flush_tlb_multi, which also flushes the
> local CPU's TLB, instead of flush_tlb_others that does not. This
> interface is more performant since it parallelize remote and local TLB
> flushes.
>
> The actual implementation of flush_tlb_multi() is almost identical to
> that of flush_tlb_others().

This confused me a bit. I thought we didn't support paravirtualized
flush_tlb_multi() from reading earlier in the series.

But, it seems like that might be Xen-only and doesn't apply to KVM and
paravirtualized KVM has no problem supporting flush_tlb_multi(). Is
that right? It might be good to include some of that background in the
changelog to set the context.