KVM: x86: Unify TSC logic
Move the TSC control logic from the vendor backends into x86.c
by adding adjust_tsc_offset to x86 ops. Now all TSC decisions
can be done in one place.
Signed-off-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 138746d..275a81d 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -505,7 +505,6 @@
vmcs_clear(vmx->vmcs);
if (per_cpu(current_vmcs, cpu) == vmx->vmcs)
per_cpu(current_vmcs, cpu) = NULL;
- rdtscll(vmx->vcpu.arch.host_tsc);
list_del(&vmx->local_vcpus_link);
vmx->vcpu.cpu = -1;
vmx->launched = 0;
@@ -881,7 +880,6 @@
static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
- u64 tsc_this, delta, new_offset;
u64 phys_addr = __pa(per_cpu(vmxarea, cpu));
if (!vmm_exclusive)
@@ -898,14 +896,12 @@
struct desc_ptr *gdt = &__get_cpu_var(host_gdt);
unsigned long sysenter_esp;
- kvm_migrate_timers(vcpu);
kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
local_irq_disable();
list_add(&vmx->local_vcpus_link,
&per_cpu(vcpus_on_cpu, cpu));
local_irq_enable();
- vcpu->cpu = cpu;
/*
* Linux uses per-cpu TSS and GDT, so set these when switching
* processors.
@@ -915,16 +911,6 @@
rdmsrl(MSR_IA32_SYSENTER_ESP, sysenter_esp);
vmcs_writel(HOST_IA32_SYSENTER_ESP, sysenter_esp); /* 22.2.3 */
-
- /*
- * Make sure the time stamp counter is monotonous.
- */
- rdtscll(tsc_this);
- if (tsc_this < vcpu->arch.host_tsc) {
- delta = vcpu->arch.host_tsc - tsc_this;
- new_offset = vmcs_read64(TSC_OFFSET) + delta;
- vmcs_write64(TSC_OFFSET, new_offset);
- }
}
}
@@ -1153,6 +1139,12 @@
vmcs_write64(TSC_OFFSET, offset);
}
+static void vmx_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment)
+{
+ u64 offset = vmcs_read64(TSC_OFFSET);
+ vmcs_write64(TSC_OFFSET, offset + adjustment);
+}
+
/*
* Reads an msr value (of 'msr_index') into 'pdata'.
* Returns 0 on success, non-0 otherwise.
@@ -4108,6 +4100,7 @@
cpu = get_cpu();
vmx_vcpu_load(&vmx->vcpu, cpu);
+ vmx->vcpu.cpu = cpu;
err = vmx_vcpu_setup(vmx);
vmx_vcpu_put(&vmx->vcpu);
put_cpu();
@@ -4347,6 +4340,7 @@
.has_wbinvd_exit = cpu_has_vmx_wbinvd_exit,
.write_tsc_offset = vmx_write_tsc_offset,
+ .adjust_tsc_offset = vmx_adjust_tsc_offset,
};
static int __init vmx_init(void)