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

From: Cornelia Huck
Date: Wed Apr 22 2020 - 09:46:09 EST


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?

> restore_gs_cb(current->thread.gs_cb);
> }
> preempt_enable();