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Date:   Thu, 16 Apr 2020 10:50:19 +0200
From:   Cornelia Huck <cohuck@redhat.com>
To:     Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Cc:     Marc Zyngier <maz@kernel.org>,
        Vitaly Kuznetsov <vkuznets@redhat.com>, kvm@vger.kernel.org,
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Subject: Re: [PATCH v2] KVM: Optimize kvm_arch_vcpu_ioctl_run function
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On Thu, 16 Apr 2020 16:45:33 +0800
Tianjia Zhang <tianjia.zhang@linux.alibaba.com> wrote:

> On 2020/4/16 16:28, Marc Zyngier wrote:
> > On 2020-04-16 08:03, Vitaly Kuznetsov wrote: =20
> >> Tianjia Zhang <tianjia.zhang@linux.alibaba.com> writes:
> >> =20
> >>> In earlier versions of kvm, 'kvm_run' is an independent structure
> >>> and is not included in the vcpu structure. At present, 'kvm_run'
> >>> is already included in the vcpu structure, so the parameter
> >>> 'kvm_run' is redundant.
> >>>
> >>> This patch simplify the function definition, removes the extra
> >>> 'kvm_run' parameter, and extract it from the 'kvm_vcpu' structure
> >>> if necessary.
> >>>
> >>> Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
> >>> ---
> >>>
> >>> v2 change:
> >>> =C2=A0 remove 'kvm_run' parameter and extract it from 'kvm_vcpu'
> >>>
> >>> =C2=A0arch/mips/kvm/mips.c=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 |=C2=
=A0 3 ++-
> >>> =C2=A0arch/powerpc/kvm/powerpc.c |=C2=A0 3 ++-
> >>> =C2=A0arch/s390/kvm/kvm-s390.c=C2=A0=C2=A0 |=C2=A0 3 ++-
> >>> =C2=A0arch/x86/kvm/x86.c=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0 | 11 ++++++-----
> >>> =C2=A0include/linux/kvm_host.h=C2=A0=C2=A0 |=C2=A0 2 +-
> >>> =C2=A0virt/kvm/arm/arm.c=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0 |=C2=A0 6 +++---
> >>> =C2=A0virt/kvm/kvm_main.c=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 |=
=C2=A0 2 +-
> >>> =C2=A07 files changed, 17 insertions(+), 13 deletions(-)

> > Overall, there is a large set of cleanups to be done when both the vcpu=
=20
> > and the run
> > structures are passed as parameters at the same time. Just grepping the=
=20
> > tree for
> > kvm_run is pretty instructive.
> >=20
> >  =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 M. =20
>=20
> Sorry, it's my mistake, I only compiled the x86 platform, I will submit=20
> patch again.

I think it's completely fine (and even preferable) to do cleanups like
that on top.

[FWIW, I compiled s390 here.]