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

From: Christian Borntraeger
Date: Wed Apr 22 2020 - 11:58:23 EST




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.