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Date:   Tue, 8 Aug 2023 08:07:43 -0700
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Subject: Re: [PATCH v7 02/12] KVM: arm64: Use kvm_arch_flush_remote_tlbs()
From:   Sean Christopherson <seanjc@google.com>
To:     Raghavendra Rao Ananta <rananta@google.com>
Cc:     Marc Zyngier <maz@kernel.org>,
        Oliver Upton <oliver.upton@linux.dev>,
        James Morse <james.morse@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Huacai Chen <chenhuacai@kernel.org>,
        Zenghui Yu <yuzenghui@huawei.com>,
        Anup Patel <anup@brainfault.org>,
        Atish Patra <atishp@atishpatra.org>,
        Jing Zhang <jingzhangos@google.com>,
        Reiji Watanabe <reijiw@google.com>,
        Colton Lewis <coltonlewis@google.com>,
        David Matlack <dmatlack@google.com>,
        linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev,
        linux-mips@vger.kernel.org, kvm-riscv@lists.infradead.org,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
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On Fri, Aug 04, 2023, Raghavendra Rao Ananta wrote:
> On Wed, Aug 2, 2023 at 4:28=E2=80=AFPM Raghavendra Rao Ananta
> <rananta@google.com> wrote:
> >
> > Sure, I'll change it to kvm_arch_flush_vm_tlbs() in v8.
> >
> While working on the renaming, I realized that since this function is
> called from kvm_main.c's kvm_flush_remote_tlbs(). Do we want to rename
> this and the other kvm_flush_*() functions that the series introduces
> to match their kvm_arch_flush_*() counterparts?

Hmm, if we're going to rename one arch hook, then yes, I think it makes sen=
se to
rename all the common APIs and arch hooks to match.

However, x86 is rife with the "remote_tlbs" nomenclature, and renaming the =
common
APIs will just push the inconsistencies into x86.  While I 100% agree that =
the
current naming is flawed, I am not willing to end up with x86 being partial=
ly
converted.

I think I'm ok renaming all of x86's many hooks?  But I'd definitely want i=
nput
from more x86 folks, and the size and scope of this series would explode.  =
Unless
Marc objects and/or has a better idea, the least awful option is probably t=
o ignore
the poor "remote_tlbs" naming and tackle it in a separate series.

Sorry for not noticiing this earlier, I didn't realize just how much x86 us=
es
remote_tlbs.

> (spiraling more into this, we also have the 'remote_tlb_flush_requests' a=
nd
> 'remote_tlb_flush' stats)

Regardless of what we decide for the APIs, definitely leave the stats alone=
.  The
names are ABI.  We could preserve the names and changes the struct fields, =
but that
would be a net negative IMO.