From ad721883e9c5f46cc5fa9496bc12c097c6238b4a Mon Sep 17 00:00:00 2001 From: Haozhong Zhang Date: Tue, 20 Oct 2015 15:39:02 +0800 Subject: [PATCH] KVM: x86: Add a common TSC scaling ratio field in kvm_vcpu_arch This patch moves the field of TSC scaling ratio from the architecture struct vcpu_svm to the common struct kvm_vcpu_arch. Signed-off-by: Haozhong Zhang Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/svm.c | 26 +++++++++++--------------- arch/x86/kvm/x86.c | 9 ++++++++- 3 files changed, 20 insertions(+), 16 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 5333767560c0..f3354bd92364 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -505,6 +505,7 @@ struct kvm_vcpu_arch { u32 virtual_tsc_mult; u32 virtual_tsc_khz; s64 ia32_tsc_adjust_msr; + u64 tsc_scaling_ratio; atomic_t nmi_queued; /* unprocessed asynchronous NMIs */ unsigned nmi_pending; /* NMI queued after currently running handler */ diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 74712ead9787..9c92e6f429d0 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -158,8 +158,6 @@ struct vcpu_svm { unsigned long int3_rip; u32 apf_reason; - u64 tsc_ratio; - /* cached guest cpuid flags for faster access */ bool nrips_enabled : 1; }; @@ -991,24 +989,22 @@ static u64 __scale_tsc(u64 ratio, u64 tsc) static u64 svm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc) { - struct vcpu_svm *svm = to_svm(vcpu); u64 _tsc = tsc; - if (svm->tsc_ratio != TSC_RATIO_DEFAULT) - _tsc = __scale_tsc(svm->tsc_ratio, tsc); + if (vcpu->arch.tsc_scaling_ratio != TSC_RATIO_DEFAULT) + _tsc = __scale_tsc(vcpu->arch.tsc_scaling_ratio, tsc); return _tsc; } static void svm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale) { - struct vcpu_svm *svm = to_svm(vcpu); u64 ratio; u64 khz; /* Guest TSC same frequency as host TSC? */ if (!scale) { - svm->tsc_ratio = TSC_RATIO_DEFAULT; + vcpu->arch.tsc_scaling_ratio = TSC_RATIO_DEFAULT; return; } @@ -1033,7 +1029,7 @@ static void svm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale) user_tsc_khz); return; } - svm->tsc_ratio = ratio; + vcpu->arch.tsc_scaling_ratio = ratio; } static u64 svm_read_tsc_offset(struct kvm_vcpu *vcpu) @@ -1067,7 +1063,7 @@ static void svm_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment, bool ho struct vcpu_svm *svm = to_svm(vcpu); if (host) { - if (svm->tsc_ratio != TSC_RATIO_DEFAULT) + if (vcpu->arch.tsc_scaling_ratio != TSC_RATIO_DEFAULT) WARN_ON(adjustment < 0); adjustment = svm_scale_tsc(vcpu, (u64)adjustment); } @@ -1238,8 +1234,6 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id) goto out; } - svm->tsc_ratio = TSC_RATIO_DEFAULT; - err = kvm_vcpu_init(&svm->vcpu, kvm, id); if (err) goto free_svm; @@ -1325,10 +1319,12 @@ static void svm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) for (i = 0; i < NR_HOST_SAVE_USER_MSRS; i++) rdmsrl(host_save_user_msrs[i], svm->host_user_msrs[i]); - if (static_cpu_has(X86_FEATURE_TSCRATEMSR) && - svm->tsc_ratio != __this_cpu_read(current_tsc_ratio)) { - __this_cpu_write(current_tsc_ratio, svm->tsc_ratio); - wrmsrl(MSR_AMD64_TSC_RATIO, svm->tsc_ratio); + if (static_cpu_has(X86_FEATURE_TSCRATEMSR)) { + u64 tsc_ratio = vcpu->arch.tsc_scaling_ratio; + if (tsc_ratio != __this_cpu_read(current_tsc_ratio)) { + __this_cpu_write(current_tsc_ratio, tsc_ratio); + wrmsrl(MSR_AMD64_TSC_RATIO, tsc_ratio); + } } } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e728c539ecfb..ef5b9d66cd71 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -113,6 +113,7 @@ u8 __read_mostly kvm_tsc_scaling_ratio_frac_bits; EXPORT_SYMBOL_GPL(kvm_tsc_scaling_ratio_frac_bits); u64 __read_mostly kvm_max_tsc_scaling_ratio; EXPORT_SYMBOL_GPL(kvm_max_tsc_scaling_ratio); +static u64 __read_mostly kvm_default_tsc_scaling_ratio; /* tsc tolerance in parts per million - default to 1/2 of the NTP threshold */ static u32 __read_mostly tsc_tolerance_ppm = 250; @@ -1258,8 +1259,11 @@ static void kvm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 this_tsc_khz) int use_scaling = 0; /* tsc_khz can be zero if TSC calibration fails */ - if (this_tsc_khz == 0) + if (this_tsc_khz == 0) { + /* set tsc_scaling_ratio to a safe value */ + vcpu->arch.tsc_scaling_ratio = kvm_default_tsc_scaling_ratio; return; + } /* Compute a scale to convert nanoseconds in TSC cycles */ kvm_get_time_scale(this_tsc_khz, NSEC_PER_SEC / 1000, @@ -7367,6 +7371,9 @@ int kvm_arch_hardware_setup(void) if (r != 0) return r; + if (kvm_has_tsc_control) + kvm_default_tsc_scaling_ratio = 1ULL << kvm_tsc_scaling_ratio_frac_bits; + kvm_init_msr_list(); return 0; } -- 2.45.2