KVM: Cache pdptrs
Instead of reloading the pdptrs on every entry and exit (vmcs writes on vmx,
guest memory access on svm) extract them on demand.
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 752465f..d726dec 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -161,6 +161,8 @@
VMX_SEGMENT_FIELD(LDTR),
};
+static void ept_save_pdptrs(struct kvm_vcpu *vcpu);
+
/*
* Keep MSR_K6_STAR at the end, as setup_msrs() will try to optimize it
* away by decrementing the array size.
@@ -1047,6 +1049,10 @@
case VCPU_REGS_RIP:
vcpu->arch.regs[VCPU_REGS_RIP] = vmcs_readl(GUEST_RIP);
break;
+ case VCPU_EXREG_PDPTR:
+ if (enable_ept)
+ ept_save_pdptrs(vcpu);
+ break;
default:
break;
}
@@ -1546,6 +1552,10 @@
static void ept_load_pdptrs(struct kvm_vcpu *vcpu)
{
+ if (!test_bit(VCPU_EXREG_PDPTR,
+ (unsigned long *)&vcpu->arch.regs_dirty))
+ return;
+
if (is_paging(vcpu) && is_pae(vcpu) && !is_long_mode(vcpu)) {
vmcs_write64(GUEST_PDPTR0, vcpu->arch.pdptrs[0]);
vmcs_write64(GUEST_PDPTR1, vcpu->arch.pdptrs[1]);
@@ -1562,6 +1572,11 @@
vcpu->arch.pdptrs[2] = vmcs_read64(GUEST_PDPTR2);
vcpu->arch.pdptrs[3] = vmcs_read64(GUEST_PDPTR3);
}
+
+ __set_bit(VCPU_EXREG_PDPTR,
+ (unsigned long *)&vcpu->arch.regs_avail);
+ __set_bit(VCPU_EXREG_PDPTR,
+ (unsigned long *)&vcpu->arch.regs_dirty);
}
static void vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
@@ -3255,10 +3270,8 @@
/* Access CR3 don't cause VMExit in paging mode, so we need
* to sync with guest real CR3. */
- if (enable_ept && is_paging(vcpu)) {
+ if (enable_ept && is_paging(vcpu))
vcpu->arch.cr3 = vmcs_readl(GUEST_CR3);
- ept_save_pdptrs(vcpu);
- }
if (unlikely(vmx->fail)) {
kvm_run->exit_reason = KVM_EXIT_FAIL_ENTRY;
@@ -3567,7 +3580,8 @@
#endif
);
- vcpu->arch.regs_avail = ~((1 << VCPU_REGS_RIP) | (1 << VCPU_REGS_RSP));
+ vcpu->arch.regs_avail = ~((1 << VCPU_REGS_RIP) | (1 << VCPU_REGS_RSP)
+ | (1 << VCPU_EXREG_PDPTR));
vcpu->arch.regs_dirty = 0;
get_debugreg(vcpu->arch.dr6, 6);