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From:   Wanpeng Li <kernellwp@gmail.com>
Date:   Tue, 28 Apr 2020 08:47:05 +0800
Message-ID: <CANRm+CyNOnCDEwAK04Yr_Yom3ebfKH61_3-fXaCs-LbcTiEd7w@mail.gmail.com>
Subject: Re: [PATCH v3 1/5] KVM: VMX: Introduce generic fastpath handler
To:     Sean Christopherson <sean.j.christopherson@intel.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, kvm <kvm@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        Haiwei Li <lihaiwei@tencent.com>
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On Tue, 28 Apr 2020 at 02:26, Sean Christopherson
<sean.j.christopherson@intel.com> wrote:
>
> On Fri, Apr 24, 2020 at 02:22:40PM +0800, Wanpeng Li wrote:
> > From: Wanpeng Li <wanpengli@tencent.com>
> >
> > Introduce generic fastpath handler to handle MSR fastpath, VMX-preemption
> > timer fastpath etc. In addition, we can't observe benefit from single
> > target IPI fastpath when APICv is disabled, let's just enable IPI and
> > Timer fastpath when APICv is enabled for now.
>
> There are three different changes being squished into a single patch:
>
>   - Refactor code to add helper
>   - Change !APICv behavior for WRMSR fastpath
>   - Introduce EXIT_FASTPATH_CONT_RUN
>
> I don't think you necessarily need to break this into three separate
> patches, but's the !APICv change needs to be a standalone patch, especially
> given the shortlog.  E.g. the refactoring could be introduced along with
> the second fastpath case, and CONT_RUN could be introduced with its first
> usage.

Agreed, will split to two separate patches.

    Wanpeng