Re: [PATCH v8 09/10] KVM: VMX: Open code VMX preemption timer rate mask in its accessor

Xiaoyao Li
2024-06-12T01:54:16Z

On 6/6/2024 7:19 AM, Sean Christopherson wrote:
> From: Xin Li <xin3.li@intel.com>
>
> Use vmx_misc_preemption_timer_rate() to get the rate in hardware_setup(),
> and open code the rate's bitmask in vmx_misc_preemption_timer_rate() so
> that the function looks like all the helpers that grab values from
> VMX_BASIC and VMX_MISC MSR values.
>
> No functional change intended.
>
> Cc: Shan Kang <shan.kang@intel.com>
> Cc: Kai Huang <kai.huang@intel.com>
> Signed-off-by: Xin Li <xin3.li@intel.com>
> [sean: split to separate patch, write changelog]
> Reviewed-by: Kai Huang <kai.huang@intel.com>

Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>

> Signed-off-by: Sean Christopherson <seanjc@google.com>
> ---
> arch/x86/include/asm/vmx.h | 3 +--
> arch/x86/kvm/vmx/vmx.c | 2 +-
> 2 files changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
> index 400819ccb42c..f7fd4369b821 100644
> --- a/arch/x86/include/asm/vmx.h
> +++ b/arch/x86/include/asm/vmx.h
> @@ -153,7 +153,6 @@ static inline u64 vmx_basic_encode_vmcs_info(u32 revision, u16 size, u8 memtype)
> return revision | ((u64)size << 32) | ((u64)memtype << 50);
> }
>
> -#define VMX_MISC_PREEMPTION_TIMER_RATE_MASK GENMASK_ULL(4, 0)
> #define VMX_MISC_SAVE_EFER_LMA BIT_ULL(5)
> #define VMX_MISC_ACTIVITY_HLT BIT_ULL(6)
> #define VMX_MISC_ACTIVITY_SHUTDOWN BIT_ULL(7)
> @@ -167,7 +166,7 @@ static inline u64 vmx_basic_encode_vmcs_info(u32 revision, u16 size, u8 memtype)
>
> static inline int vmx_misc_preemption_timer_rate(u64 vmx_misc)
> {
> - return vmx_misc & VMX_MISC_PREEMPTION_TIMER_RATE_MASK;
> + return vmx_misc & GENMASK_ULL(4, 0);
> }
>
> static inline int vmx_misc_cr3_count(u64 vmx_misc)
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index 3141ef8679e2..69865e7a3506 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -8536,7 +8536,7 @@ __init int vmx_hardware_setup(void)
> u64 use_timer_freq = 5000ULL * 1000 * 1000;
>
> cpu_preemption_timer_multi =
> - vmcs_config.misc & VMX_MISC_PREEMPTION_TIMER_RATE_MASK;
> + vmx_misc_preemption_timer_rate(vmcs_config.misc);
>
> if (tsc_khz)
> use_timer_freq = (u64)tsc_khz * 1000;