Re: [PATCH v2 1/7] KVM: s390: clean up redundant 'kvm_run' parameters

[Tianjia Zhang]

On 2020/4/22 23:58, Christian Borntraeger wrote:
> On 22.04.20 15:45, Cornelia Huck wrote:
> > On Wed, 22 Apr 2020 20:58:04 +0800
> > Tianjia Zhang <tianjia.zhang@xxxxxxxxxxxxxxxxx> wrote:
> >
> > > In the current kvm version, 'kvm_run' has been included in the 'kvm_vcpu'
> > > structure. Earlier than historical reasons, many kvm-related function
> >
> > s/Earlier than/For/ ?
> >
> > > parameters retain the 'kvm_run' and 'kvm_vcpu' parameters at the same time.
> > > This patch does a unified cleanup of these remaining redundant parameters.
> > >
> > > Signed-off-by: Tianjia Zhang <tianjia.zhang@xxxxxxxxxxxxxxxxx>
> > > ---
> > >   arch/s390/kvm/kvm-s390.c | 37 ++++++++++++++++++++++---------------
> > >   1 file changed, 22 insertions(+), 15 deletions(-)
> > >
> > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> > > index e335a7e5ead7..d7bb2e7a07ff 100644
> > > --- a/arch/s390/kvm/kvm-s390.c
> > > +++ b/arch/s390/kvm/kvm-s390.c
> > > @@ -4176,8 +4176,9 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
> > >   	return rc;
> > >   }
> > >   
> > > -static void sync_regs_fmt2(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
> > > +static void sync_regs_fmt2(struct kvm_vcpu *vcpu)
> > >   {
> > > +	struct kvm_run *kvm_run = vcpu->run;
> > >   	struct runtime_instr_cb *riccb;
> > >   	struct gs_cb *gscb;
> > >   
> > > @@ -4235,7 +4236,7 @@ static void sync_regs_fmt2(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
> > >   		}
> > >   		if (vcpu->arch.gs_enabled) {
> > >   			current->thread.gs_cb = (struct gs_cb *)
> > > -						&vcpu->run->s.regs.gscb;
> > > +						&kvm_run->s.regs.gscb;
> >
> > Not sure if these changes (vcpu->run-> => kvm_run->) are really worth
> > it. (It seems they amount to at least as much as the changes advertised
> > in the patch description.)
> >
> > Other opinions?
>
> Agreed. It feels kind of random. Maybe just do the first line (move kvm_run from the
> function parameter list into the variable declaration)? Not sure if this is better.

Why not, `kvm_run` is equivalent to `vcpu->run`, which is also part of 
the cleanup, or do you mean to put this change in another patch?

Thanks,
Tianjia