From 07c1419a32bbba08cf1efb6d1ecaf24f174fa4c3 Mon Sep 17 00:00:00 2001 From: Haozhong Zhang Date: Tue, 20 Oct 2015 15:39:05 +0800 Subject: [PATCH] KVM: x86: Replace call-back compute_tsc_offset() with a common function Both VMX and SVM calculate the tsc-offset in the same way, so this patch removes the call-back compute_tsc_offset() and replaces it with a common function kvm_compute_tsc_offset(). Signed-off-by: Haozhong Zhang Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 - arch/x86/kvm/svm.c | 10 ---------- arch/x86/kvm/vmx.c | 6 ------ arch/x86/kvm/x86.c | 15 ++++++++++++--- 4 files changed, 12 insertions(+), 20 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index c5a3f3d66e90..672f960e8144 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -856,7 +856,6 @@ struct kvm_x86_ops { u64 (*read_tsc_offset)(struct kvm_vcpu *vcpu); void (*write_tsc_offset)(struct kvm_vcpu *vcpu, u64 offset); - u64 (*compute_tsc_offset)(struct kvm_vcpu *vcpu, u64 target_tsc); u64 (*read_l1_tsc)(struct kvm_vcpu *vcpu, u64 host_tsc); void (*get_exit_info)(struct kvm_vcpu *vcpu, u64 *info1, u64 *info2); diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index f6e49a6c9ab0..d99b175ffbea 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1004,15 +1004,6 @@ static void svm_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment, bool ho mark_dirty(svm->vmcb, VMCB_INTERCEPTS); } -static u64 svm_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc) -{ - u64 tsc; - - tsc = kvm_scale_tsc(vcpu, rdtsc()); - - return target_tsc - tsc; -} - static void init_vmcb(struct vcpu_svm *svm) { struct vmcb_control_area *control = &svm->vmcb->control; @@ -4370,7 +4361,6 @@ static struct kvm_x86_ops svm_x86_ops = { .read_tsc_offset = svm_read_tsc_offset, .write_tsc_offset = svm_write_tsc_offset, .adjust_tsc_offset = svm_adjust_tsc_offset, - .compute_tsc_offset = svm_compute_tsc_offset, .read_l1_tsc = svm_read_l1_tsc, .set_tdp_cr3 = set_tdp_cr3, diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index baee46893899..2d4782ce9a93 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2426,11 +2426,6 @@ static void vmx_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment, bool ho offset + adjustment); } -static u64 vmx_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc) -{ - return target_tsc - rdtsc(); -} - static bool guest_cpuid_has_vmx(struct kvm_vcpu *vcpu) { struct kvm_cpuid_entry2 *best = kvm_find_cpuid_entry(vcpu, 1, 0); @@ -10813,7 +10808,6 @@ static struct kvm_x86_ops vmx_x86_ops = { .read_tsc_offset = vmx_read_tsc_offset, .write_tsc_offset = vmx_write_tsc_offset, .adjust_tsc_offset = vmx_adjust_tsc_offset, - .compute_tsc_offset = vmx_compute_tsc_offset, .read_l1_tsc = vmx_read_l1_tsc, .set_tdp_cr3 = vmx_set_cr3, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c314e8d22a67..bb46066e125b 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1392,6 +1392,15 @@ u64 kvm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc) } EXPORT_SYMBOL_GPL(kvm_scale_tsc); +static u64 kvm_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc) +{ + u64 tsc; + + tsc = kvm_scale_tsc(vcpu, rdtsc()); + + return target_tsc - tsc; +} + void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr) { struct kvm *kvm = vcpu->kvm; @@ -1403,7 +1412,7 @@ void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr) u64 data = msr->data; raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags); - offset = kvm_x86_ops->compute_tsc_offset(vcpu, data); + offset = kvm_compute_tsc_offset(vcpu, data); ns = get_kernel_ns(); elapsed = ns - kvm->arch.last_tsc_nsec; @@ -1460,7 +1469,7 @@ void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr) } else { u64 delta = nsec_to_cycles(vcpu, elapsed); data += delta; - offset = kvm_x86_ops->compute_tsc_offset(vcpu, data); + offset = kvm_compute_tsc_offset(vcpu, data); pr_debug("kvm: adjusted tsc offset by %llu\n", delta); } matched = true; @@ -2687,7 +2696,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) if (tsc_delta < 0) mark_tsc_unstable("KVM discovered backwards TSC"); if (check_tsc_unstable()) { - u64 offset = kvm_x86_ops->compute_tsc_offset(vcpu, + u64 offset = kvm_compute_tsc_offset(vcpu, vcpu->arch.last_guest_tsc); kvm_x86_ops->write_tsc_offset(vcpu, offset); vcpu->arch.tsc_catchup = 1; -- 2.20.1