KVM: SVM: optimize nested vmrun
Only copy the necessary parts of the vmcb save area on vmrun and save
precious time.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 2f5f223..f11f880 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1681,6 +1681,7 @@
{
struct vmcb *nested_vmcb = (struct vmcb *)arg1;
struct vmcb *hsave = svm->hsave;
+ struct vmcb *vmcb = svm->vmcb;
/* nested_vmcb is our indicator if nested SVM is activated */
svm->nested_vmcb = svm->vmcb->save.rax;
@@ -1691,12 +1692,25 @@
/* Save the old vmcb, so we don't need to pick what we save, but
can restore everything when a VMEXIT occurs */
- memcpy(hsave, svm->vmcb, sizeof(struct vmcb));
- /* We need to remember the original CR3 in the SPT case */
- if (!npt_enabled)
- hsave->save.cr3 = svm->vcpu.arch.cr3;
- hsave->save.cr4 = svm->vcpu.arch.cr4;
- hsave->save.rip = svm->next_rip;
+ hsave->save.es = vmcb->save.es;
+ hsave->save.cs = vmcb->save.cs;
+ hsave->save.ss = vmcb->save.ss;
+ hsave->save.ds = vmcb->save.ds;
+ hsave->save.gdtr = vmcb->save.gdtr;
+ hsave->save.idtr = vmcb->save.idtr;
+ hsave->save.efer = svm->vcpu.arch.shadow_efer;
+ hsave->save.cr0 = svm->vcpu.arch.cr0;
+ hsave->save.cr4 = svm->vcpu.arch.cr4;
+ hsave->save.rflags = vmcb->save.rflags;
+ hsave->save.rip = svm->next_rip;
+ hsave->save.rsp = vmcb->save.rsp;
+ hsave->save.rax = vmcb->save.rax;
+ if (npt_enabled)
+ hsave->save.cr3 = vmcb->save.cr3;
+ else
+ hsave->save.cr3 = svm->vcpu.arch.cr3;
+
+ hsave->control = vmcb->control;
if (svm->vmcb->save.rflags & X86_EFLAGS_IF)
svm->vcpu.arch.hflags |= HF_HIF_MASK;
@@ -1721,7 +1735,7 @@
kvm_set_cr3(&svm->vcpu, nested_vmcb->save.cr3);
kvm_mmu_reset_context(&svm->vcpu);
}
- svm->vmcb->save.cr2 = nested_vmcb->save.cr2;
+ svm->vmcb->save.cr2 = svm->vcpu.arch.cr2 = nested_vmcb->save.cr2;
kvm_register_write(&svm->vcpu, VCPU_REGS_RAX, nested_vmcb->save.rax);
kvm_register_write(&svm->vcpu, VCPU_REGS_RSP, nested_vmcb->save.rsp);
kvm_register_write(&svm->vcpu, VCPU_REGS_RIP, nested_vmcb->save.rip);