linux-kernel - [PATCH v2 13/25] KVM: x86/mmu: cleanup computation of MMU roles for shadow paging

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Message-Id: <20220221162243.683208-14-pbonzini@redhat.com>
Date:   Mon, 21 Feb 2022 11:22:31 -0500
From:   Paolo Bonzini <pbonzini@...hat.com>
To:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc:     dmatlack@...gle.com, seanjc@...gle.com
Subject: [PATCH v2 13/25] KVM: x86/mmu: cleanup computation of MMU roles for shadow paging

Pass the already-computed CPU mode, instead of redoing it.

Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
---
 arch/x86/kvm/mmu/mmu.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 0a08ab8e2e4e..725aef55c08f 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4775,13 +4775,11 @@ static void init_kvm_tdp_mmu(struct kvm_vcpu *vcpu,
 
 static union kvm_mmu_role
 kvm_calc_shadow_mmu_root_page_role(struct kvm_vcpu *vcpu,
-				   const struct kvm_mmu_role_regs *regs)
+				   union kvm_mmu_role role)
 {
-	union kvm_mmu_role role = kvm_calc_cpu_mode(vcpu, regs);
-
-	if (!____is_efer_lma(regs))
+	if (!role.ext.efer_lma)
 		role.base.level = PT32E_ROOT_LEVEL;
-	else if (____is_cr4_la57(regs))
+	else if (role.ext.cr4_la57)
 		role.base.level = PT64_ROOT_5LEVEL;
 	else
 		role.base.level = PT64_ROOT_4LEVEL;
@@ -4820,18 +4818,15 @@ static void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu,
 	struct kvm_mmu *context = &vcpu->arch.root_mmu;
 	union kvm_mmu_role cpu_mode = kvm_calc_cpu_mode(vcpu, regs);
 	union kvm_mmu_role mmu_role =
-		kvm_calc_shadow_mmu_root_page_role(vcpu, regs);
+		kvm_calc_shadow_mmu_root_page_role(vcpu, cpu_mode);
 
 	shadow_mmu_init_context(vcpu, context, cpu_mode, mmu_role);
 }
 
 static union kvm_mmu_role
 kvm_calc_shadow_npt_root_page_role(struct kvm_vcpu *vcpu,
-				   const struct kvm_mmu_role_regs *regs)
+				   union kvm_mmu_role role)
 {
-	union kvm_mmu_role role =
-               kvm_calc_cpu_mode(vcpu, regs);
-
 	role.base.level = kvm_mmu_get_tdp_level(vcpu);
 
 	return role;
@@ -4847,7 +4842,7 @@ void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0,
 		.efer = efer,
 	};
 	union kvm_mmu_role cpu_mode = kvm_calc_cpu_mode(vcpu, &regs);
-	union kvm_mmu_role mmu_role = kvm_calc_shadow_npt_root_page_role(vcpu, &regs);;
+	union kvm_mmu_role mmu_role = kvm_calc_shadow_npt_root_page_role(vcpu, cpu_mode);
 
 	shadow_mmu_init_context(vcpu, context, cpu_mode, mmu_role);
 	kvm_mmu_new_pgd(vcpu, nested_cr3);
-- 
2.31.1