Re: [PATCH v2 1/5] KVM: X86: Dynamic allocate core residency msr state

From: Sean Christopherson
Date: Wed Jun 12 2019 - 12:06:03 EST


On Tue, Jun 11, 2019 at 03:34:07PM +0800, Wanpeng Li wrote:
> From: Wanpeng Li <wanpengli@xxxxxxxxxxx>
>
> Dynamic allocate core residency msr state. MSR_CORE_C1_RES is unreadable
> except for ATOM platform, so it is ignore here.
>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
> Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
> ---
> arch/x86/include/asm/kvm_host.h | 11 +++++++++++
> arch/x86/kvm/vmx/vmx.c | 5 +++++
> 2 files changed, 16 insertions(+)
>
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index 15e973d..bd615ee 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -538,6 +538,15 @@ struct kvm_vcpu_hv {
> cpumask_t tlb_flush;
> };
>
> +#define NR_CORE_RESIDENCY_MSRS 3
> +
> +struct kvm_residency_msr {
> + s64 value;
> + u32 index;
> + bool delta_from_host;
> + bool count_with_host;
> +};
> +
> struct kvm_vcpu_arch {
> /*
> * rip and regs accesses must go through
> @@ -785,6 +794,8 @@ struct kvm_vcpu_arch {
>
> /* AMD MSRC001_0015 Hardware Configuration */
> u64 msr_hwcr;
> +
> + struct kvm_residency_msr *core_cstate_msrs;

Why are these in kvm_vcpu_arch? AFAICT they're only wired up for VMX.

> };
>
> struct kvm_lpage_info {
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index 0b241f4..4dc2459 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -6658,6 +6658,11 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
> goto free_vmcs;
> }
>
> + vmx->vcpu.arch.core_cstate_msrs = kzalloc(sizeof(struct kvm_residency_msr) *
> + NR_CORE_RESIDENCY_MSRS, GFP_KERNEL_ACCOUNT);
> + if (!vmx->vcpu.arch.core_cstate_msrs)
> + goto free_vmcs;
> +
> if (nested)
> nested_vmx_setup_ctls_msrs(&vmx->nested.msrs,
> vmx_capability.ept,
> --
> 2.7.4
>