Re: [PATCH 3/3] KVM: implement spinlock optimization logic for arm/s390

From: David Hildenbrand
Date: Mon Aug 07 2017 - 04:52:20 EST


On 07.08.2017 10:44, Longpeng(Mike) wrote:
> Implements the kvm_arch_vcpu_spin/preempt_in_kernel() for arm/s390,
> they needn't cache the result.
>
> Signed-off-by: Longpeng(Mike) <longpeng2@xxxxxxxxxx>
> ---
> arch/s390/kvm/kvm-s390.c | 4 ++--
> virt/kvm/arm/arm.c | 4 ++--
> 2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index f78cdc2..49b9178 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -2449,12 +2449,12 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
>
> bool kvm_arch_vcpu_spin_in_kernel(struct kvm_vcpu *vcpu)
> {
> - return false;
> + return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE);
> }
>
> bool kvm_arch_vcpu_preempt_in_kernel(struct kvm_vcpu *vcpu)
> {
> - return false;
> + return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE);
> }
>
> void kvm_s390_vcpu_block(struct kvm_vcpu *vcpu)
> diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
> index e45f780..956f025 100644
> --- a/virt/kvm/arm/arm.c
> +++ b/virt/kvm/arm/arm.c
> @@ -418,12 +418,12 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
>
> bool kvm_arch_vcpu_spin_in_kernel(struct kvm_vcpu *vcpu)
> {
> - return false;
> + return vcpu_mode_priv(vcpu);
> }
>
> bool kvm_arch_vcpu_preempt_in_kernel(struct kvm_vcpu *vcpu)
> {
> - return false;
> + return vcpu_mode_priv(vcpu);
> }
>
> /* Just ensure a guest exit from a particular CPU */
>

Can you split that into two parts? (arm and s390x?)

--

Thanks,

David