This patch changes the kvm_guest_time_update function to use TSC frequency the guest actually has for updating its clock.
Signed-off-by: Joerg Roedel <[email protected]> --- arch/x86/include/asm/kvm_host.h | 6 +++--- arch/x86/kvm/x86.c | 25 +++++++++++++++---------- 2 files changed, 18 insertions(+), 13 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 35f81b1..0344b94 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -380,7 +380,10 @@ struct kvm_vcpu_arch { u64 last_kernel_ns; u64 last_tsc_nsec; u64 last_tsc_write; + u32 virtual_tsc_khz; bool tsc_catchup; + u32 tsc_catchup_mult; + s8 tsc_catchup_shift; bool nmi_pending; bool nmi_injected; @@ -450,9 +453,6 @@ struct kvm_arch { u64 last_tsc_nsec; u64 last_tsc_offset; u64 last_tsc_write; - u32 virtual_tsc_khz; - u32 virtual_tsc_mult; - s8 virtual_tsc_shift; struct kvm_xen_hvm_config xen_hvm_config; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 1b8b16a..1e7af86 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -982,6 +982,14 @@ static inline int kvm_tsc_changes_freq(void) return ret; } +static u64 vcpu_tsc_khz(struct kvm_vcpu *vcpu) +{ + if (vcpu->arch.virtual_tsc_khz) + return vcpu->arch.virtual_tsc_khz; + else + return __this_cpu_read(cpu_tsc_khz); +} + static inline u64 nsec_to_cycles(u64 nsec) { u64 ret; @@ -995,20 +1003,19 @@ static inline u64 nsec_to_cycles(u64 nsec) return ret; } -static void kvm_arch_set_tsc_khz(struct kvm *kvm, u32 this_tsc_khz) +static void kvm_init_tsc_catchup(struct kvm_vcpu *vcpu, u32 this_tsc_khz) { /* Compute a scale to convert nanoseconds in TSC cycles */ kvm_get_time_scale(this_tsc_khz, NSEC_PER_SEC / 1000, - &kvm->arch.virtual_tsc_shift, - &kvm->arch.virtual_tsc_mult); - kvm->arch.virtual_tsc_khz = this_tsc_khz; + &vcpu->arch.tsc_catchup_shift, + &vcpu->arch.tsc_catchup_mult); } static u64 compute_guest_tsc(struct kvm_vcpu *vcpu, s64 kernel_ns) { u64 tsc = pvclock_scale_delta(kernel_ns-vcpu->arch.last_tsc_nsec, - vcpu->kvm->arch.virtual_tsc_mult, - vcpu->kvm->arch.virtual_tsc_shift); + vcpu->arch.tsc_catchup_mult, + vcpu->arch.tsc_catchup_shift); tsc += vcpu->arch.last_tsc_write; return tsc; } @@ -1075,8 +1082,7 @@ static int kvm_guest_time_update(struct kvm_vcpu *v) local_irq_save(flags); kvm_get_msr(v, MSR_IA32_TSC, &tsc_timestamp); kernel_ns = get_kernel_ns(); - this_tsc_khz = __this_cpu_read(cpu_tsc_khz); - + this_tsc_khz = vcpu_tsc_khz(v); if (unlikely(this_tsc_khz == 0)) { local_irq_restore(flags); kvm_make_request(KVM_REQ_CLOCK_UPDATE, v); @@ -5955,8 +5961,7 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) } vcpu->arch.pio_data = page_address(page); - if (!kvm->arch.virtual_tsc_khz) - kvm_arch_set_tsc_khz(kvm, max_tsc_khz); + kvm_init_tsc_catchup(vcpu, max_tsc_khz); r = kvm_mmu_create(vcpu); if (r < 0) -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
