[PATCH 3/3] KVM: MMU: Consolidate common code in mmu_free_roots()

[Takuya Yoshikawa <yoshikawa_takuya_b1@xxxxxxxxxxxxx>]

By making the last three statements common to both if/else cases, the
symmetry between the locking and unlocking becomes clearer. One note
here is that VCPU's root_hpa does not need to be protected by mmu_lock.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@xxxxxxxxxxxxx>
---
 arch/x86/kvm/mmu.c |   39 +++++++++++++++++++--------------------
 1 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index d01f340..bf80b46 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2861,42 +2861,41 @@ out_unlock:
 static void mmu_free_roots(struct kvm_vcpu *vcpu)
 {
 	int i;
+	hpa_t root;
 	struct kvm_mmu_page *sp;
 	LIST_HEAD(invalid_list);
 
 	if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
 		return;
+
 	spin_lock(&vcpu->kvm->mmu_lock);
+
 	if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL &&
 	    (vcpu->arch.mmu.root_level == PT64_ROOT_LEVEL ||
 	     vcpu->arch.mmu.direct_map)) {
-		hpa_t root = vcpu->arch.mmu.root_hpa;
-
+		root = vcpu->arch.mmu.root_hpa;
 		sp = page_header(root);
 		--sp->root_count;
-		if (!sp->root_count && sp->role.invalid) {
+		if (!sp->root_count && sp->role.invalid)
 			kvm_mmu_prepare_zap_page(vcpu->kvm, sp, &invalid_list);
-			kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
+	} else {
+		for (i = 0; i < 4; ++i) {
+			root = vcpu->arch.mmu.pae_root[i];
+			if (root) {
+				root &= PT64_BASE_ADDR_MASK;
+				sp = page_header(root);
+				--sp->root_count;
+				if (!sp->root_count && sp->role.invalid)
+					kvm_mmu_prepare_zap_page(vcpu->kvm, sp,
+								 &invalid_list);
+			}
+			vcpu->arch.mmu.pae_root[i] = INVALID_PAGE;
 		}
-		vcpu->arch.mmu.root_hpa = INVALID_PAGE;
-		spin_unlock(&vcpu->kvm->mmu_lock);
-		return;
 	}
-	for (i = 0; i < 4; ++i) {
-		hpa_t root = vcpu->arch.mmu.pae_root[i];
 
-		if (root) {
-			root &= PT64_BASE_ADDR_MASK;
-			sp = page_header(root);
-			--sp->root_count;
-			if (!sp->root_count && sp->role.invalid)
-				kvm_mmu_prepare_zap_page(vcpu->kvm, sp,
-							 &invalid_list);
-		}
-		vcpu->arch.mmu.pae_root[i] = INVALID_PAGE;
-	}
 	kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
 	spin_unlock(&vcpu->kvm->mmu_lock);
+
 	vcpu->arch.mmu.root_hpa = INVALID_PAGE;
 }
 
-- 
1.7.5.4

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