From f4e1b3c8bd2a044cd0ccf80595bfd088a49fe60b Mon Sep 17 00:00:00 2001 From: Zachary Amsden Date: Thu, 19 Aug 2010 22:07:16 -1000 Subject: [PATCH] KVM: x86: Convert TSC writes to TSC offset writes Change svm / vmx to be the same internally and write TSC offset instead of bare TSC in helper functions. Isolated as a single patch to contain code movement. Signed-off-by: Zachary Amsden Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/svm.c | 31 +++++++++++++++++-------------- arch/x86/kvm/vmx.c | 11 +++++------ 2 files changed, 22 insertions(+), 20 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index af5b9ea..e06f00d 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -701,6 +701,20 @@ static void init_sys_seg(struct vmcb_seg *seg, uint32_t type) seg->base = 0; } +static void svm_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset) +{ + struct vcpu_svm *svm = to_svm(vcpu); + u64 g_tsc_offset = 0; + + if (is_nested(svm)) { + g_tsc_offset = svm->vmcb->control.tsc_offset - + svm->nested.hsave->control.tsc_offset; + svm->nested.hsave->control.tsc_offset = offset; + } + + svm->vmcb->control.tsc_offset = offset + g_tsc_offset; +} + static void init_vmcb(struct vcpu_svm *svm) { struct vmcb_control_area *control = &svm->vmcb->control; @@ -901,7 +915,7 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id) svm->vmcb_pa = page_to_pfn(page) << PAGE_SHIFT; svm->asid_generation = 0; init_vmcb(svm); - svm->vmcb->control.tsc_offset = 0-native_read_tsc(); + svm_write_tsc_offset(&svm->vcpu, 0-native_read_tsc()); err = fx_init(&svm->vcpu); if (err) @@ -2566,20 +2580,9 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 data) struct vcpu_svm *svm = to_svm(vcpu); switch (ecx) { - case MSR_IA32_TSC: { - u64 tsc_offset = data - native_read_tsc(); - u64 g_tsc_offset = 0; - - if (is_nested(svm)) { - g_tsc_offset = svm->vmcb->control.tsc_offset - - svm->nested.hsave->control.tsc_offset; - svm->nested.hsave->control.tsc_offset = tsc_offset; - } - - svm->vmcb->control.tsc_offset = tsc_offset + g_tsc_offset; - + case MSR_IA32_TSC: + svm_write_tsc_offset(vcpu, data - native_read_tsc()); break; - } case MSR_STAR: svm->vmcb->save.star = data; break; diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 4fbab24..d9bec5e 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -1149,9 +1149,9 @@ static u64 guest_read_tsc(void) * writes 'guest_tsc' into guest's timestamp counter "register" * guest_tsc = host_tsc + tsc_offset ==> tsc_offset = guest_tsc - host_tsc */ -static void guest_write_tsc(u64 guest_tsc, u64 host_tsc) +static void vmx_write_tsc_offset(u64 offset) { - vmcs_write64(TSC_OFFSET, guest_tsc - host_tsc); + vmcs_write64(TSC_OFFSET, offset); } /* @@ -1255,7 +1255,7 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data) break; case MSR_IA32_TSC: rdtscll(host_tsc); - guest_write_tsc(data, host_tsc); + vmx_write_tsc_offset(data - host_tsc); break; case MSR_IA32_CR_PAT: if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT) { @@ -2512,7 +2512,7 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx) { u32 host_sysenter_cs, msr_low, msr_high; u32 junk; - u64 host_pat, tsc_this; + u64 host_pat; unsigned long a; struct desc_ptr dt; int i; @@ -2653,8 +2653,7 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx) vmx->vcpu.arch.cr4_guest_owned_bits |= X86_CR4_PGE; vmcs_writel(CR4_GUEST_HOST_MASK, ~vmx->vcpu.arch.cr4_guest_owned_bits); - tsc_this = native_read_tsc(); - guest_write_tsc(0, tsc_this); + vmx_write_tsc_offset(0-native_read_tsc()); return 0; } -- 2.7.4