From 4ba76538dd52dd9b18b464e509cb8f3ed4ed993f Mon Sep 17 00:00:00 2001 From: Haozhong Zhang Date: Tue, 20 Oct 2015 15:39:07 +0800 Subject: [PATCH] KVM: x86: Move TSC scaling logic out of call-back read_l1_tsc() Both VMX and SVM scales the host TSC in the same way in call-back read_l1_tsc(), so this patch moves the scaling logic from call-back read_l1_tsc() to a common function kvm_read_l1_tsc(). Signed-off-by: Haozhong Zhang Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/lapic.c | 4 ++-- arch/x86/kvm/svm.c | 3 +-- arch/x86/kvm/x86.c | 11 ++++++++--- 4 files changed, 12 insertions(+), 7 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 8465944fe8da..456a3869a57e 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1226,6 +1226,7 @@ void kvm_define_shared_msr(unsigned index, u32 msr); int kvm_set_shared_msr(unsigned index, u64 val, u64 mask); u64 kvm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc); +u64 kvm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc); unsigned long kvm_get_linear_rip(struct kvm_vcpu *vcpu); bool kvm_is_linear_rip(struct kvm_vcpu *vcpu, unsigned long linear_rip); diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index ecd4ea1d28a8..4d30b865be30 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1250,7 +1250,7 @@ void wait_lapic_expire(struct kvm_vcpu *vcpu) tsc_deadline = apic->lapic_timer.expired_tscdeadline; apic->lapic_timer.expired_tscdeadline = 0; - guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, rdtsc()); + guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc()); trace_kvm_wait_lapic_expire(vcpu->vcpu_id, guest_tsc - tsc_deadline); /* __delay is delay_tsc whenever the hardware has TSC, thus always. */ @@ -1318,7 +1318,7 @@ static void start_apic_timer(struct kvm_lapic *apic) local_irq_save(flags); now = apic->lapic_timer.timer.base->get_time(); - guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, rdtsc()); + guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc()); if (likely(tscdeadline > guest_tsc)) { ns = (tscdeadline - guest_tsc) * 1000000ULL; do_div(ns, this_tsc_khz); diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index b5824a3894bf..f2ba91990b4e 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2984,8 +2984,7 @@ static int cr8_write_interception(struct vcpu_svm *svm) static u64 svm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc) { struct vmcb *vmcb = get_host_vmcb(to_svm(vcpu)); - return vmcb->control.tsc_offset + - kvm_scale_tsc(vcpu, host_tsc); + return vmcb->control.tsc_offset + host_tsc; } static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 4073009fe578..3d008de9cb05 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1401,6 +1401,12 @@ static u64 kvm_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc) return target_tsc - tsc; } +u64 kvm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc) +{ + return kvm_x86_ops->read_l1_tsc(vcpu, kvm_scale_tsc(vcpu, host_tsc)); +} +EXPORT_SYMBOL_GPL(kvm_read_l1_tsc); + void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr) { struct kvm *kvm = vcpu->kvm; @@ -1738,7 +1744,7 @@ static int kvm_guest_time_update(struct kvm_vcpu *v) kernel_ns = get_kernel_ns(); } - tsc_timestamp = kvm_x86_ops->read_l1_tsc(v, host_tsc); + tsc_timestamp = kvm_read_l1_tsc(v, host_tsc); /* * We may have to catch up the TSC to match elapsed wall clock @@ -6545,8 +6551,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) if (hw_breakpoint_active()) hw_breakpoint_restore(); - vcpu->arch.last_guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, - rdtsc()); + vcpu->arch.last_guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc()); vcpu->mode = OUTSIDE_GUEST_MODE; smp_wmb(); -- 2.20.1