KVM: VMX: Do Hyper-V TLB flush iff vCPU's EPTP hasn't been flushed

Combine the for-loops for Hyper-V TLB EPTP checking and flushing, and in
doing so skip flushes for vCPUs whose EPTP matches the target EPTP.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210305183123.3978098-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index a1adc5f..67457a7 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -505,33 +505,26 @@ static int hv_remote_flush_tlb_with_range(struct kvm *kvm,
 
        spin_lock(&kvm_vmx->ept_pointer_lock);
 
-       if (kvm_vmx->ept_pointers_match == EPT_POINTERS_CHECK) {
+       if (kvm_vmx->ept_pointers_match != EPT_POINTERS_MATCH) {
                kvm_vmx->ept_pointers_match = EPT_POINTERS_MATCH;
                kvm_vmx->hv_tlb_eptp = INVALID_PAGE;
 
                kvm_for_each_vcpu(i, vcpu, kvm) {
                        tmp_eptp = to_vmx(vcpu)->ept_pointer;
-                       if (!VALID_PAGE(tmp_eptp))
+                       if (!VALID_PAGE(tmp_eptp) ||
+                           tmp_eptp == kvm_vmx->hv_tlb_eptp)
                                continue;
 
-                       if (!VALID_PAGE(kvm_vmx->hv_tlb_eptp)) {
+                       if (!VALID_PAGE(kvm_vmx->hv_tlb_eptp))
                                kvm_vmx->hv_tlb_eptp = tmp_eptp;
-                       } else if (kvm_vmx->hv_tlb_eptp != tmp_eptp) {
-                               kvm_vmx->hv_tlb_eptp = INVALID_PAGE;
+                       else
                                kvm_vmx->ept_pointers_match
                                        = EPT_POINTERS_MISMATCH;
-                               break;
-                       }
-               }
-       }
 
-       if (kvm_vmx->ept_pointers_match != EPT_POINTERS_MATCH) {
-               kvm_for_each_vcpu(i, vcpu, kvm) {
-                       /* If ept_pointer is invalid pointer, bypass flush request. */
-                       if (VALID_PAGE(to_vmx(vcpu)->ept_pointer))
-                               ret |= hv_remote_flush_eptp(to_vmx(vcpu)->ept_pointer,
-                                                           range);
+                       ret |= hv_remote_flush_eptp(tmp_eptp, range);
                }
+               if (kvm_vmx->ept_pointers_match == EPT_POINTERS_MISMATCH)
+                       kvm_vmx->hv_tlb_eptp = INVALID_PAGE;
        } else if (VALID_PAGE(kvm_vmx->hv_tlb_eptp)) {
                ret = hv_remote_flush_eptp(kvm_vmx->hv_tlb_eptp, range);
        }